University of Southern California Dissertations and Theses

Hydrogen transfer reactions catalyzed by iridium and ruthenium complexes

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Hydrogen transfer reactions catalyzed by iridium and ruthenium complexes

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Content HYDROGEN TRANSFER REACTIONS CATALYZED BY IRIDIUM AND RUTHENIUM COMPLEXES
by
Valeriy Cherepakhin
A Dissertation Presented to the
FACULTY OF THE USC GRADUATE SCHOOL
UNIVERSITY OF SOUTHERN CALIFORNIA
in Partial Fulfillment of the
Requirements for the Degree
DOCTOR OF PHILOSOPHY
(CHEMISTRY)
December 2020
Copyright 2020 Valeriy Cherepakhin
ii
Acknowledgements
Here, I am going to express my gratitude to the beautiful people whose contribution made this work
possible.
I thank my mother, Svetlana Cherepakhina, for tolerating my arrogance and taking care of me all
these years. My wonderful teachers deserve appreciation for making high school my second home and
instilling a long-lasting adoration of science. Especially, my chemistry teacher, Irina Tashina, who let me
take over the school chemistry lab and guided me toward a successful application to Lomonosov Moscow
State University. I want to give credit to an old friend, Alexander Bunev, who despite his unethical style of
work acquainted me with organic synthesis and inspired me to become a chemist.
My undergraduate advisor, Kirill Zaitsev, deserves recognition for teaching me some advanced
experimental skills that proved to be lifesaving in the following years of graduate school. I thank my friends
Ekaterina Lysenko and Maria Orekhova for their love and support that were so important to me during
the years of college. Moreover, E. Lysenko lured me to take an adventure of moving to the United States,
which I am thankful for.
Much gratitude must be given to my dear colleagues: Anju Nalikezhathu, Nicolas Alfonso, Carlos
Navarro, Van Do, Yuhao Chen, Long Zhang, Alex Maertens, Talya Kapenstein, and Lisa Kam for teaching
me to appreciate the utility of my knowledge. Former graduate students from Williams group: Jeff Celaje,
Zhiyao Lu, and Ivan Demianets deserve an acknowledgement, since only by “standing on the shoulders of
giants” I could see a bit further.
I thank my favorite philosophers: Plato, Georg W. F. Hegel, and Vadim Mezhuev for introducing me
to the art of asking the right questions, thus liberating my mind and showing how to find eternity within
temporal existence of material objects.
Above all, I thank my advisor, Professor Travis Williams, for giving me the opportunity to work in his
team and to bring to this world a series of exciting publications. He is an incredible person whose
iii
tremendous capacity for kindness, patience, and positive energy helped me to overcome ignorance and,
ultimately, discover God.
iv
Table of Contents
Acknowledgements ......................................................................................................................................ii
List of Tables ...............................................................................................................................................vii
List of Schemes...........................................................................................................................................viii
List of Figures ...............................................................................................................................................ix
Abstract.......................................................................................................................................................xii
Chapter 1. Direct Oxidation of Primary Alcohols to Carboxylic Acids...........................................................1
1.1. Introduction .......................................................................................................................................1
1.2. Thermodynamics of Primary Alcohol Oxidation ................................................................................2
1.3. Oxometallate Oxidation .....................................................................................................................4
1.4. Transfer Dehydrogenation ...............................................................................................................11
1.5. Acceptorless Dehydrogenation........................................................................................................13
1.6. Electrochemical Methods ................................................................................................................20
1.7. Outlook ............................................................................................................................................21
1.8. References .......................................................................................................................................22
Chapter 2. Iridium Catalysts for Acceptorless Dehydrogenation of Alcohols to Carboxylic Acids: Scope
and Mechanism ..........................................................................................................................................33
2.1. Introduction .....................................................................................................................................33
2.2. Results and Discussion .....................................................................................................................34
2.2.1. Alcohol Oxidation ......................................................................................................................34
2.2.2. Mechanism ................................................................................................................................40
2.3. Conclusions ......................................................................................................................................48
2.4. Experimental Section .......................................................................................................................49
2.4.1. Materials and Methods .............................................................................................................49
2.4.2. General Procedure for Alcohol Dehydrogenation .....................................................................49
2.4.3. Synthesis of Iridium Complexes.................................................................................................68
2.4.4. Decomposition of 2.6 ................................................................................................................78
2.4.5. Isomerization of 2.8 to 2.10 ......................................................................................................80
2.4.6. Deuteration of 2.8 .....................................................................................................................85
2.4.7. Comparison of the Catalytic Activity of 2.2 and 2.8 ..................................................................86
2.4.8. Conversion of 2.8 to 2.11 ..........................................................................................................87
2.4.9. Deprotonation of 2.8.................................................................................................................89
2.4.10. Dehydrogenation of Benzaldehyde .........................................................................................90
2.4.11. Formation of 1-Butoxyhexan-1-ol ...........................................................................................91
2.5. References .......................................................................................................................................92
Chapter 3. Catalyst Evolution in Iridium-Catalyzed Dehydrogenation of Formic Acid ...............................96
3.1. Introduction .....................................................................................................................................96
3.2. Results and Discussion .....................................................................................................................96
v
3.2.1. Synthesis of Catalytic Intermediates .........................................................................................96
3.2.2. Reactivity of Catalytic Intermediates.........................................................................................98
3.2.3. Mechanism of Precatalyst Activation......................................................................................102
3.3. Conclusions ....................................................................................................................................103
3.4. Experimental Section .....................................................................................................................104
3.4.1. Materials and Methods ...........................................................................................................104
3.4.2. Synthesis of Iridium Complexes...............................................................................................104
3.4.3. Conversion of 3.1 to 3.2 in HCOONa/HCOOH Solution at Room Temperature.......................117
3.4.4. Conversion of 3.2 to 3.4 in HCOONa/HCOOH Solution at 90
o
C..............................................117
3.4.5. Conversion of 3.3 to 3.4 in HCOOH solution at 90
o
C..............................................................118
3.4.6. Selective Deuteration of 3.3 in HCOONa/DCOOD Solution at Room Temperature ................119
3.4.7. Conversion of 3.3-d
2
to 3.2-d
n
in HCOONa/DCOOD Solution at Room Temperature..............121
3.4.8. Generation of 3.4 from 3.1 and 3.5.........................................................................................122
3.4.9. Conversion of 3.5 to 3.6 ..........................................................................................................124
3.4.10. Hydrogenation of 3.5.............................................................................................................125
3.4.11. Stepwise Catalytic Cycle Experiment.....................................................................................126
3.5. References .....................................................................................................................................127
Chapter 4. Catalyst Evolution in Ruthenium-Catalyzed Coupling of Amines and Alcohols ......................129
4.1. Introduction ...................................................................................................................................129
4.2. Results and Discussion ...................................................................................................................130
4.2.1. Coupling of Aliphatic Amines and Alcohols .............................................................................130
4.2.2. Time-Course Study. Synthesis and Characterization of Ruthenium Complexes......................133
4.2.3. Mechanism of Precatalyst Evolution and Death .....................................................................138
4.2.4. Electrochemistry......................................................................................................................143
4.3. Conclusions ....................................................................................................................................145
4.4. Experimental Section .....................................................................................................................145
4.4.1. Materials and Methods ...........................................................................................................145
4.4.2. General Procedure for Coupling of Amines and Alcohols .......................................................146
4.4.3. Synthesis of Ruthenium Complexes ........................................................................................155
4.4.4. Formation of Complexes 4.5 and 4.6 Tracked by
1
H NMR Spectroscopy................................169
4.4.5. Characterization of Complex 4.4 Predecessors .......................................................................171
4.4.6. Electrochemical Study of Complex 4.4 ....................................................................................172
4.5. References .....................................................................................................................................173
Chapter 5. Heterobimetallic Complexes of IrM (M = Fe
II
, Co
II
, and Ni
II
) Core and Bridging
2-(Diphenylphosphino)pyridine: Electronic Structure and Electrochemical Behavior .............................180
5.1. Introduction ...................................................................................................................................180
5.2. Results and Discussion ...................................................................................................................181
5.2.1. Synthesis and Structure of the Metal Complexes ...................................................................181
5.2.2. Spectroscopic Studies..............................................................................................................183
5.2.3. Computational studies ............................................................................................................185
5.2.4. Electrochemical studies...........................................................................................................187
5.3. Conclusions ....................................................................................................................................190
5.4. Experimental Section .....................................................................................................................190
5.4.1. Materials and Methods ...........................................................................................................190
5.4.2. Synthetic Procedures and Characterization Data....................................................................191
vi
5.5. References .....................................................................................................................................197
Appendix. X-Ray Crystallography Data .....................................................................................................201
Crystal Structure of 2.7 .........................................................................................................................201
Crystal Structure of 2.8 .........................................................................................................................208
Crystal Structure of 3.3 .........................................................................................................................215
Crystal Structure of 3.5 .........................................................................................................................224
Crystal Structure of 4.4 .........................................................................................................................236
Crystal Structure of 4.6 .........................................................................................................................254
Crystal Structure of 5.2 .........................................................................................................................268
Crystal Structure of 5.3 .........................................................................................................................280
Crystal Structure of 5.4 .........................................................................................................................292
vii
List of Tables
Table 1.1. The standard electrode potentials (E
o
vs. RHE, V) for reduction of high-valent transition
element oxo and hydroxo complexes in alkaline (pH = 14, blue) and acidic (pH = 0, red) aqueous
solutions and their ability to oxidize alcohols and aldehydes. .....................................................................5
Table 1.2. Characteristics of catalytic acceptorless dehydrogenation methods. .......................................14
Table 1.3. Characteristics of ruthenium-catalyzed acceptorless dehydrogenation methods. ...................16
Table 2.1. Selectivity screening of catalysts 2.1 – 2.5. ...............................................................................35
Table 2.2. Substrate scope for dehydrogenation of primary alcohols using pre-catalysts 2.1 and 2.2......38
Table 4.1. Coupling of 1-aminohexane with 1-butanol. ...........................................................................131
Table 4.2. Expansion of substrate scope for amine-alcohol coupling. .....................................................132
Table 4.3. Catalytic activity comparison test............................................................................................140
Table 5.1. Summarized spectroscopic data..............................................................................................183
Table 5.2. The dominant natural transition orbital pairs for the excited states corresponding to the
largest oscillator strength for 5.1 – 5.4. ...................................................................................................185
Table 5.3. Assignment of the experimental UV-Vis absorption bands.....................................................186
viii
List of Schemes
Scheme 1.1. Comparison of alcohol-to-acid oxidation methods. ................................................................2
Scheme 1.2. Oxidation of chiral amino alcohols by TEMPO/NaClO/NaClO
2
system. .................................10
Scheme 1.3. Pathways of an aldehyde dimerization under the catalytic conditions.................................11
Scheme 1.4. Catalytic transfer dehydrogenation of citronellol and geraniol.............................................12
Scheme 1.5. Catalytic dehydrogenation of amino alcohols by complex 23. ..............................................17
Scheme 1.6. Dehydrogenation of glycerol to lactate by ruthenium and iridium catalysts. .......................18
Scheme 1.7. Electrosynthesis of an amino acid derivative. .......................................................................21
Scheme 2.1. Reactions of complexes 2.1 and 2.2. .....................................................................................41
Scheme 2.2. Reactions of complex 2.8.......................................................................................................43
Scheme 2.3. Mechanism of precatalyst 2.2 activation...............................................................................46
Scheme 2.4. Mechanisms of aldehyde and carboxylate formation. ..........................................................47
Scheme 3.1. Dehydrogenation of formic acid catalyzed by complex 3.1...................................................96
Scheme 3.2. Synthesis of intermediate 3.3................................................................................................97
Scheme 3.3. Synthesis of intermediate 3.5................................................................................................98
Scheme 3.4. Generation of intermediates 3.2 and 3.3 at room temperature. ..........................................99
Scheme 3.5. Generation and degradation of the catalyst resting state 3.4.............................................101
Scheme 3.6. Reactions of Intermediate 3.5. ............................................................................................102
Scheme 3.7. Proposed mechanism of 3.1 activation and the catalytic cycle. ..........................................103
Scheme 4.1. Synthesis of intermediate 4.3..............................................................................................135
Scheme 4.2. Synthesis of intermediate 4.4..............................................................................................136
Scheme 4.3. Synthesis of intermediates 4.5 and 4.6. ..............................................................................137
Scheme 4.4. Ruthenium-catalyzed alcohol oxidation. .............................................................................141
Scheme 4.5. Precatalyst activation and death. ........................................................................................142
Scheme 4.6. Formation of structurally related catalytic complexes. .......................................................143
Scheme 5.1. Syntheses of complexes 5.2 – 5.4........................................................................................181
ix
List of Figures
Figure 1.1. A. Gibbs free energy profiles for oxidation of hydrocarbons with water
(RCH
3
: H
2
O = 1:2, left). B. Frost diagrams for carbon (right)........................................................................3
Figure 1.2. Examples of catalysts for stoichiometric oxidation of alcohols to carboxylates. .....................10
Figure 1.3. Pharmaceutical agents synthesized from alcohols using complex 6........................................13
Figure 1.4. Examples of ruthenium catalysts for acceptorless dehydrogenation of alcohols to
carboxylates................................................................................................................................................15
Figure 1.5. Examples of iridium catalysts for acceptorless dehydrogenation of alcohols to
carboxylates................................................................................................................................................19
Figure 2.1. Iridium complexes 2.1 – 2.5. ....................................................................................................34
Figure 2.2. Hydrogen evolution profiles of benzyl alcohol dehydrogenation with 2.1, 2.2, and 2.5. ........36
Figure 2.3. Molecular structures of 2.7 (left) and 2.8 (right) shown with 50% probability ellipsoids. .......41
Figure 2.4.
1
H NMR spectra (600 MHz, C
6
D
6
) demonstrating IrH peaks. ....................................................44
Figure 2.5.
1
H and
13
C{
1
H} NMR spectra of 2a in D
2
O. ................................................................................51
Figure 2.6.
1
H and
13
C{
1
H} NMR spectra of 2b in D
2
O. ................................................................................52
Figure 2.7.
1
H and
13
C{
1
H} NMR spectra of 2c in CD
3
OD. ............................................................................53
Figure 2.8.
1
H and
13
C{
1
H} NMR spectra of 2d in D
2
O. ................................................................................54
Figure 2.9.
1
H and
13
C{
1
H} NMR spectra of 2e in CDCl
3
...............................................................................55
Figure 2.10.
1
H and
13
C{
1
H} NMR spectra of 2f in DMSO-d
6
........................................................................56
Figure 2.11.
1
H and
13
C{
1
H} NMR spectra of 2g in DMSO-d
6
.......................................................................57
Figure 2.12.
1
H and
13
C{
1
H} NMR spectra of 2h in CD
3
OD...........................................................................58
Figure 2.13.
1
H and
13
C{
1
H} NMR spectra of 2i in DMSO-d
6
........................................................................59
Figure 2.14.
1
H and
13
C{
1
H} NMR spectra of 2j in DMSO-d
6
........................................................................60
Figure 2.15.
1
H and
13
C{
1
H} NMR spectra of 2k in DMSO-d
6
.......................................................................61
Figure 2.16.
1
H and
13
C{
1
H} NMR spectra of 2l in DMSO-d
6
........................................................................62
Figure 2.17.
1
H and
13
C{
1
H} NMR spectra of 2m in D
2
O. .............................................................................63
Figure 2.18.
1
H and
13
C{
1
H} NMR spectra of 2n in CDCl
3
.............................................................................64
Figure 2.19.
1
H and
13
C{
1
H} NMR spectra of 2o in CDCl
3
.............................................................................65
Figure 2.20.
1
H and
13
C{
1
H} NMR spectra of 2p in CD
3
OD...........................................................................66
Figure 2.21.
1
H and
13
C{
1
H} NMR spectra of 2q in D
2
O. ..............................................................................67
Figure 2.22.
1
H NMR spectrum of 2.6 in C
6
D
6
.............................................................................................68
Figure 2.23. HSQC (top) and HMBC (bottom) NMR spectra of 2.6 in C
6
D
6
.................................................69
Figure 2.24.
1
H EXSY NMR spectrum of 2.6 in C
6
D
6
(excitation at 4.85 ppm).............................................70
Figure 2.25.
1
H NOESY NMR spectrum of 2.6 in C
6
D
6
. ................................................................................70
Figure 2.26.
1
H NMR spectrum of 2.7 in C
6
D
6
.............................................................................................71
Figure 2.27.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 2.7 in C
6
D
6
. .....................................................................72
Figure 2.28. COSY (top) and HSQC (bottom) NMR spectra of 2.7 in C
6
D
6
. .................................................73
Figure 2.29.
1
H NMR spectra of 2.8 in C
6
D
6
. ...............................................................................................75
Figure 2 30.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 2.8 in C
6
D
6
. .....................................................................76
Figure 2.31. COSY NMR spectrum of 2.8 in C
6
D
6
. .......................................................................................77
Figure 2.32.
1
H NMR spectrum of 2.6 decomposition products in C
6
D
6
.....................................................78
Figure 2.33. COSY (top) and HMBC (bottom) NMR spectra of 2.6 decomposition products in C
6
D
6
. ........79
Figure 2.34.
1
H NMR spectrum of 2.10 in C
6
D
6
...........................................................................................80
Figure 2.35.
31
P{
1
H} NMR spectrum of 2.10 in C
6
D
6
....................................................................................81
Figure 2.36. Time-course study of 2.8 isomerization by
1
H NMR (toluene-d
8
, 25
o
C). ...............................81
x
Figure 2.37. Kinetic profile of 2.8 isomerization. .......................................................................................82
Figure 2.38. HSQC (top) and
1
H–
13
C HMBC (bottom) NMR spectra of the equilibrium mixture of 2.8
and 2.10 (toluene-d
8
, 25
o
C). ......................................................................................................................83
Figure 2.39.
1
H–
31
P HMBC NMR spectra of the equilibrium mixture of 2.8 and 2.10 (toluene-d
8
, 25
and 100
o
C). ................................................................................................................................................84
Figure 2.40.
1
H NMR spectrum of deuterated 2.8 in C
6
D
6
(hydride signals)...............................................85
Figure 2.41. Hydrogen evolution profiles of benzyl alcohol dehydrogenation with complexes 2.2
and 2.8........................................................................................................................................................86
Figure 2.42.
1
H NMR spectrum of the reaction between 2.8 and n-hexanal (C
6
D
6
, 25
o
C).........................87
Figure 2.43.
1
H and
31
P{
1
H} NMR spectra of crude 2.11 in toluene-d
8
........................................................88
Figure 2.44. Reversible deprotonation of 2.8 in C
6
D
6
monitored by
1
H NMR. ...........................................89
Figure 2.45. Hydrogen evolution profile of benzaldehyde dehydrogenation. ...........................................90
Figure 2.46.
1
H NMR spectra demonstrating formation of 1-butoxyhexan-1-ol. .......................................91
Figure 3.1. Molecular structures of the cations of 3.3 (left) and 3.5 (right) shown with 50%
probability ellipsoids...................................................................................................................................97
Figure 3.2.
31
P{
1
H} NMR spectra of the reaction mixture demonstrating transformation of 3.2
to 3.4 at 90
o
C. ..........................................................................................................................................100
Figure 3.3.
1
H NMR spectra of 3.3 in CD
2
Cl
2
. ............................................................................................106
Figure 3.4.
31
P{
1
H} NMR spectra of 3.3 in CD
2
Cl
2
(top) and HCOOH (bottom)..........................................107
Figure 3.5. COSY NMR spectra of 3.3 in CD
2
Cl
2
. .......................................................................................108
Figure 3.6.
13
C{
1
H} NMR spectrum of 3.3 in CD
2
Cl
2
...................................................................................109
Figure 3.7.
19
F NMR spectrum of 3.3 in CD
2
Cl
2
. ........................................................................................109
Figure 3.8.
1
H NMR spectrum of 3.4-d
3
in DCOOD/HCOONa. ..................................................................110
Figure 3.9.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 3.4-d
3
in DCOOD/HCOONa.............................................111
Figure 3.10.
1
H and
13
C{
1
H} NMR spectra of 3.5 in CD
2
Cl
2
. .......................................................................113
Figure 3.11.
19
F (top) and
31
P{
1
H} (bottom) NMR spectra of 3.5 in CD
2
Cl
2
................................................114
Figure 3.12.
19
F (top) and
31
P{
1
H} (bottom) NMR spectra of 3.6 in CD
2
Cl
2
................................................115
Figure 3.13.
1
H NMR spectra of 3.6 in CD
2
Cl
2
. ..........................................................................................116
Figure 3.14.
31
P{
1
H} NMR spectra demonstrating conversion of 3.1 to 3.2 at room temperature. .........117
Figure 3.15.
31
P{
1
H} NMR spectra demonstrating conversion of 3.3 to 3.4 at 90
o
C. ...............................118
Figure 3.16. Fragments of
1
H NMR spectra of complexes 3.3 and 3.3-d
2
demonstrating selective
deuteration of the formate ligand resonating at 8.60 ppm. ....................................................................119
Figure 3.17. COSY NMR spectrum of complex 3.3-d
2
demonstrating persistence of the formate
ligand resonating at 7.76 ppm..................................................................................................................120
Figure 3.18. Fragments of
1
H NMR spectra of complexes 3.3 and 3.3-d
2
demonstrating selective
deuteration of the terminal hydride ligand resonating at –26.54 ppm....................................................120
Figure 3.19.
31
P{
1
H} NMR spectrum demonstrating complexes 3.2-d
n
and 3.3-d
2
at equilibrium in
HCOONa/DCOOD solution........................................................................................................................121
Figure 3.20. Fragments of
1
H NMR spectra demonstrating identity of the solutions obtained in the
experiments 1 and 2.................................................................................................................................122
Figure 3.21. Fragments of
31
P{
1
H} NMR spectra demonstrating identity of the solutions obtained
in the experiments 1 and 2.......................................................................................................................123
Figure 3.22.
1
H (top) and
31
P{
1
H} (bottom) NMR spectra demonstrating formation of complex 3.6. ......124
Figure 3.23.
1
H and
31
P{
1
H} NMR spectra demonstrating formation of 3.5-H
2
.........................................125
Figure 3.24.
1
H NMR spectra demonstrating sequential transformation 3.5 → 3.4 → 3.5-H
2
→ 3.5. .....126
Figure 4.1. Precatalysts for alcohol-amine coupling. ...............................................................................130
xi
Figure 4.2.
31
P{
1
H} NMR spectra of the crude reaction mixture demonstrating consecutive
formation of complexes 4.3 – 4.6.............................................................................................................134
Figure 4.3. Molecular structures of the cations of 4.4 (left) and 4.6 (right) shown with 50%
probability ellipsoids.................................................................................................................................137
Figure 4.4. Coupling patterns of the hydride ligands in
1
H NMR spectra of diastereomers 4.5 and 4.6..138
Figure 4.5. Cyclic voltammogram of 4.4 (1.0 mM) in CH
2
Cl
2
with 0.1 M [Bu
4
N]PF
6
at a scan rate
of 50 mV/s. ...............................................................................................................................................144
Figure 4.6.
1
H and
13
C{
1
H} NMR spectra of 4a in CDCl
3
.............................................................................149
Figure 4.7.
1
H and
13
C{
1
H} NMR spectra of 4b in CDCl
3
.............................................................................150
Figure 4.8.
1
H and
13
C{
1
H} NMR spectra of 4c in CDCl
3
. ............................................................................151
Figure 4.9.
1
H and
13
C{
1
H} NMR spectra of 4d in CDCl
3
.............................................................................152
Figure 4.10.
1
H and
13
C{
1
H} NMR spectra of 4e in CDCl
3
...........................................................................153
Figure 4.11.
1
H and
13
C{
1
H} NMR spectra of 4f in CDCl
3
. ..........................................................................154
Figure 4.12.
31
P{
1
H} and
19
F NMR spectra of 4.2 in CD
2
Cl
2
........................................................................156
Figure 4.13.
1
H and
13
C{
1
H} NMR spectra of 4.2 in CD
2
Cl
2
. .......................................................................157
Figure 4.14.
31
P{
1
H} and
19
F NMR spectra of 4.3 in CD
2
Cl
2
........................................................................159
Figure 4.15.
1
H and
13
C{
1
H} NMR spectra of 4.3 in CD
2
Cl
2
. .......................................................................160
Figure 4.16.
1
H and
13
C{
1
H} NMR spectra of 4.4 in CD
2
Cl
2
. .......................................................................162
Figure 4.17.
31
P{
1
H} and
19
F NMR spectra of 4.4 in CD
2
Cl
2
........................................................................163
Figure 4.18. Fragment of COSY NMR spectrum of 4.4 in CD
2
Cl
2
. .............................................................163
Figure 4.19.
31
P{
1
H} NMR spectrum of 4.5 in CD
2
Cl
2
.................................................................................164
Figure 4.20.
1
H and
13
C{
1
H} NMR spectra of 4.5 in CD
2
Cl
2
. .......................................................................165
Figure 4.21.
1
H and
13
C{
1
H} NMR spectra of 4.6 in CD
2
Cl
2
. .......................................................................167
Figure 4.22.
31
P{
1
H} and
19
F NMR spectra of 4.6 in CD
2
Cl
2
........................................................................168
Figure 4.23.
1
H NMR spectra of crude reaction mixtures from experiments 1–5. ...................................170
Figure 4.24. Top:
31
P{
1
H} NMR spectra of crude and chromatographically purified reaction mixture
terminated after 3 min. Bottom: MALDI-MS spectrum of the purified mixture showing molecular
peaks of dinuclear (785.22 Da) and trinuclear (1193.76 Da) complexes..................................................171
Figure 4.25. Top left: cyclic voltammogram of 4.4 (1.0 mM) in CH
2
Cl
2
at a scan rate of 50 mV/s.
Top right: cyclic voltammograms of 4.4 (1.0 mM) in CH
2
Cl
2
featuring a reversible wave at
E
1/2
= 0.442 V at scan rates ranging from 25 mV/s to 2000 mV/s. Bottom: Randles-Sevcik plots for
the wave at E
1/2
= 0.442 V.........................................................................................................................172
Figure 5.1. Molecular structures of 5.2, 5.3, and 5.4 shown with 50% probability ellipsoids..................182
Figure 5.2. Electronic absorption spectra of 5.1 – 5.4 in CH
2
Cl
2
at 25
o
C. ................................................184
Figure 5.3. Cyclic voltammograms of 1 mM 5.4 in CH
2
Cl
2
with 0.1 M [Bu
4
N][PF
6
] at various scan rates. 188
Figure 5.4. Plot of log(current density) versus log(scan rate) for complex 5.4. .......................................188
Figure 5.5. Plot of peak current versus the square root of the scan rate for complex 5.4. .....................189
Figure 5.6. Cyclic voltammograms of 1 mM 5.3 in THF (right) with 0.1 M [Bu
4
N][PF
6
] at various scan
rates..........................................................................................................................................................189
Figure 5.7.
1
H and
13
C{
1
H} NMR spectra of 5.1 in CD
2
Cl
2
. .........................................................................192
Figure 5.8.
31
P{
1
H} NMR spectrum of 5.1 in CD
2
Cl
2
...................................................................................193
Figure 5.9.
1
H and
31
P{
1
H} NMR spectra of 5.2 in CD
2
Cl
2
. .........................................................................194
Figure 5.10.
1
H NMR spectrum of 5.3 in CD
2
Cl
2
........................................................................................195
Figure 5.11.
1
H and
31
P{
1
H} NMR spectra of 5.4 in CD
2
Cl
2
. .......................................................................196
xii
Abstract
This thesis focuses on organometallic chemistry of iridium and ruthenium complexes that enable
synthetically and economically important catalytic hydrogen transfer reactions, such as coupling of
amines and alcohols, acceptorless dehydrogenation of primary alcohols to carboxylic acids, and
dehydrogenation of formic acid. The general strategy of the research projects is concerned with analysis
of catalyst evolution mechanisms that involve precatalytic, catalytic, and post catalytic steps.
Understanding the underlying processes of homogeneous catalytic reactions is important for the design
of synthetically crucial transformations. On the other hand, this type of research benefits the
organometallic chemistry of platinum group metals.
Chapter one reviews traditional and modern methods for the direct oxidation of primary alcohols to
carboxylic acids. Within the last seven years, a great number of new methods have emerged that utilize
transition metal compounds as catalysts for acceptorless dehydrogenation of alcohols to carboxylates.
The interest in this reaction is explained by its atom economy, which is in accord with the principles of
sustainability and green chemistry. This chapter introduces the reader to our catalytic system for
acceptorless dehydrogenation of alcohols.
Chapter two describes the first iridium-based catalytic system for the conversion of primary alcohols
to potassium carboxylates (or carboxylic acids) in the presence of potassium hydroxide using either [Ir(2-
PyCH
2
(C
4
H
5
N
2
))(COD)]
+
or [Ir(PN)(COD)]
+
(PN = 2-PyCH
2
PBu
t
2
). The method provides both aliphatic and
aromatic carboxylates in high yield and with outstanding functional group tolerance. The application of
this method to a diverse variety of primary alcohols, including heterocyclic and amino alcohols was
illustrated. Complex [Ir(PN)(COD)]
+
reacts with alcohols to form the crystallographically characterized
catalytic intermediates [IrH(η
1
,η
3
-C
8
H
12
)(PN)] and [Ir
2
H
3
(CO)(PN)(μ-PN)]. Synthetic studies on several of
xiii
the iridium intermediates supported a general proposal of the mechanism of catalyst activation that
enables the alcohol dehydrogenation.
Chapter three presents a study on evolution of complex [Ir(PN)(COD)]
+
in a catalytic dehydrogenation
of neat formic acid. The complex undergoes multiple transformations and gives a series of derivatives,
including structurally characterized precatalytic intermediate [Ir
2
H
3
(μ-OOCH)
2
(PN)
2
]
+
and a
dehydrogenated form of the active catalyst [Ir
2
H(CO)
2
(PN)
2
]
+
. Elaborate time-course NMR studies suggest
a slow carbonylation of iridium at high temperature as a key step for generating the active catalyst that
can dehydrogenate formic acid even at room temperature.
Chapter four describes the mechanism, scope, and catalyst evolution for ruthenium-based coupling
of amines and alcohols, which proceeds from a [RuCl(PN)(η
6
-cymene)]
+
precatalyst. The method
selectively produces secondary amines through a hydrogen borrowing mechanism and is successfully
applied to several heterocyclic substrates. Under the reaction conditions, precatalyst evolves through a
series of catalytic intermediates: [RuH(PN)(η
6
-cymene)]
+
, [Ru
3
H
2
Cl
2
(CO)(PN)
2
(μ-PN)]
+
, and a
diastereomeric pair of [Ru
2
HCl(CO)
2
(PN)
2
(μ-O
2
CPr
n
)]
+
. A study of catalytic activity shows that
[Ru
3
H
2
Cl
2
(CO)(PN)
2
(μ-PN)]
+
is a dormant form of the catalyst, whereas the pair of [Ru
2
HCl(CO)
2
(PN)
2
(μ-
O
2
CPr
n
)]
+
are the ultimate dead forms. Factors that govern the formation of the catalytic intermediates
and the role of selective ruthenium carbonylation, which is essential for enabling generation of the active
catalyst were discussed.
Chapter five is devoted to the synthesis and study of three complexes based on Ir–M (M = Fe
II
, Co
II
,
and Ni
II
) heterobimetallic core and 2-(diphenylphosphino)pyridine (Ph
2
PPy) ligand. Their structures were
established by single-crystal X-ray diffraction as [Ir(CO)(μ-Cl)(μ-Ph
2
PPy)
2
FeCl
2
], [IrCl(CO)(μ-Ph
2
PPy)
2
CoCl
2
],
and [Ir(CO)(μ-Cl)(μ-Ph
2
PPy)
2
NiCl
2
]. Time-dependent DFT computations suggest a donor–acceptor
interaction between a filled 5dz
2
orbital on iridium and an empty orbital on the first-row metal atom,
which is supported by UV-vis studies. Magnetic moment measurements show that the first-row metals
xiv
are in their high-spin electronic configurations. Cyclic voltammetry data show that all the complexes
undergo irreversible decomposition upon either reduction or oxidation. While these complexes are not
stable to electrocatalysis conditions, the data presented here refine the understanding of the bonding
synergies of the first-row and third-row metals.
1
Chapter 1. Direct Oxidation of Primary Alcohols to Carboxylic Acids
1.1. Introduction
This chapter duplicates a manuscript that was submitted for publication to Synthesis in 2020.
Oxidation of primary alcohols to carboxylic acids is a fundamental transformation in organic
chemistry, yet despite its simplicity and extensive use, it remains a subject of active research for synthetic
organic chemists. Within the last seven years, a great number of new methods have emerged that utilize
transition metal compounds as catalysts for acceptorless dehydrogenation of alcohols to carboxylates.
The interest in this reaction is explained by its atom economy, which is in accord with the principles of
sustainability and green chemistry. Therefore, the methods for the direct synthesis of carboxylic acids
from alcohols are ripe for a modern survey, which is provided in this chapter.
Oxidation of primary alcohols to carboxylic acids is utilized extensively in total syntheses of many
important bioactive compounds, for example, luzopeptins (antitumor and antiretroviral antibiotics),
1

bistramide A,
2
verbalactone,
3
(−)-lyngbyaloside B,
4
and other medicinal scaffolds.
5
Common methods for
this oxidation use transition metal-based oxidants that generate stoichiometric portions of metallic waste,
which is environmentally unfriendly. Although this is not a problem for small scale laboratory syntheses,
the issue becomes critical when the reaction is scaled up. One approach is to replace the metal-based
oxidants with oxygen, sodium hypochlorite, or sodium chlorite, as they produce only water and sodium
chloride as by-products. Another solution is performing alcohol oxidation in an acceptorless
dehydrogenation mode, with hydrogen gas evolved as the only waste product. This reaction pathway is
enabled both by conditions based on transition metal catalysts and electrolytic reactions.
In this chapter, the alcohol oxidation methods are grouped into three categories: stoichiometric,
acceptorless, and electrolytic, based on the criteria of Gibbs free energy, reaction pH, and by-product
2
(Scheme 1.1); stoichiometric group, in turn, is subdivided into oxometallate oxidation and transfer
dehydrogenation. Stepwise methods for alcohol oxidation are reviewed elsewhere.
6,7
Scheme 1.1. Comparison of alcohol-to-acid oxidation methods.
1.2. Thermodynamics of Primary Alcohol Oxidation
Before discussing modern oxidation methods, a number of thermodynamic aspects of primary
alcohol oxidation must be addressed, since they generally establish the oxidant choice for accomplishing
a specific synthetic step.
The available thermodynamic data
8,9
on alkane-to-carboxylic acid oxidation were compiled and
represented as Gibbs free energy and Frost diagrams (Figure 1.1). The Frost diagrams for carbon can be
plotted based on experimental data or derived from the free energy profiles; these are generally
consistent in our hands. Comparing the Gibbs and Frost diagrams for methane, it is clear that although
the two graphs trend similarly, noteworthy differences arise with different reaction conditions: the Gibbs
diagram is considering the reaction participants at their standard states, while the Frost diagram is dealing
with 1 M aqueous solutions. Also, alcohols, aldehydes, and carboxylic acids are thermodynamically
unstable toward reduction, however while alcohols and acids are kinetically stable, aldehydes appear the
most reactive in the sequence.
3

Figure 1.1. A. Gibbs free energy profiles for oxidation of hydrocarbons with water (RCH
3
: H
2
O = 1:2, left).
B. Frost diagrams for carbon (right). The X-axes demonstrate the number of electrons being transferred
during a redox event, and the absolute values of n correspond to hydrocarbons (-4), alcohols (-2),
aldehydes (0), carboxylic acids (2), and carbon dioxide/carbonate (4).
The first step in the oxidation sequence of primary alcohols is dehydrogenation to the corresponding
aldehyde: RCH
2
OH
(l)
 RCHO
(l)
+ H
2(g)
. The reaction is endergonic and characterized by the Δ
r
G
o
values
56.3 (R = H), 45.9 (R = CH
3
), 29.2 (R = C
2
H
5
), and 27.5 kJ/mol (R = C
6
H
5
). The corresponding standard redox
potential for couple CH
2
(OH)
2
/CH
3
OH at pH = 0 is +0.237 V.
8
This reaction is typically performed in neutral
non aqueous solutions (to prevent hydration and overoxidation) or acidic aqueous solutions for the
synthesis of volatile aldehydes that can be removed from a boiling reaction mixture by distillation.
Once the aldehyde is formed and hydrated, an excess of oxidant can easily convert an aldehyde
hydrate to the corresponding acid. Although this second step proceeds with a slight decrease of the
system’s free energy (Figure 1.1A), the overall alcohol to carboxylic acid oxidation (RCH
2
OH
(l)
+ H
2
O
(l)

RCOOH
(l/s)
+ 2H
2(g)
) remains endergonic and is characterized by the Δ
r
G° values 42.1 (R = H), 22.0 (R = CH
3
),
24.9 (R = C
2
H
5
), and 12.9 kJ/mol (R = C
6
H
5
). These numbers, as well as the slopes of graphs in the free
energy and Frost diagrams, demonstrate that the possibility for an oxidant to convert alcohol to acid is
4
determined by redox potential of the first oxidation step (ca. +0.25 V), since it is the highest among the
two.
The system’s pH affects thermodynamics of alcohol oxidation dramatically, since all the redox
potentials depend on [H
+
] according to the Nernst equation (Figure 1.1B). Increased acidity of the species
makes their conjugate bases more stable (+0.104 vs. –0.876 V for couples HCOOH/CH
3
OH and HCOO
–
/CH
3
OH, respectively), thus decreasing the redox potentials, giving carbonate ion as the most stable form
of carbon in alkaline solution. Carboxylates behave analogously. Thus, oxidation of alcohols to
carboxylates by water in alkaline solution is extremely exergonic, so an alcohol can be oxidized
spontaneously by water to produce two equivalents of H
2
. This explains why all catalytic dehydrogenation
methods in section 5 utilize aqueous hydroxide solutions or solid alkali metal hydroxides as selective basic
regents for carboxylate generation.
Comparing the standard redox potentials for the HCOO
–
/CH
3
OH (–0.876 V) and H
2
O/H
2
(–0.828 V)
couples, methanol is expected to be oxidized by 1 M hydroxide solution at room temperature, generating
dihydrogen (Δ
r
G
o
= –18.5 kJ/mol). According to our calculations, Δ
r
G
o
of primary alcohol oxidation to
carboxylate (RCH
2
OH
(l)
+ NaOH
(s)
 RCOONa
(s)
+ 2H
2(g)
) has the following values: –36.1 (R = H), –57.6
(R = CH
3
), and –86.8 kJ/mol (R = C
6
H
5
).
10
Although the reaction is highly favored, it is extremely slow at
room temperature, and forcing conditions (350
o
C) are required to overcome the activation barrier.
11
This
is the underlying reason that modern catalyst development has been important in this space, currently
enabling methods with dramatically milder conditions (60
o
C).
12
1.3. Oxometallate Oxidation
Metal-based stoichiometric oxidizing agents are typically derived from oxo and hydroxo complexes
of high-valent transition metals. Table 1.1 summarizes all oxometallates that can oxidize alcohols or
aldehydes, with oxidation products shown in parentheses. The thermodynamic oxidative ability of the
5
oxometallates is characterized with the standard electrode potentials (E
o
vs. RHE, V)
8,13
that correspond
to reduction of a highest oxometallate to a water-stable oxide/hydroxide. Reduction of oxo complexes
requires protons, so the corresponding electrode potentials will depend on pH, thus the potential of any
redox couple in Table 1.1 varies from the lowest value at (pH = 14, blue) to the highest value (pH = 0, red).
This explains why oxo anions are generally more oxidizing in acid. Several conclusions can be drawn from
the data: the most powerful oxidants are derived from the first row metals: V, Cr, Mn, and Fe. The highest
oxometallates of Nb, Ta, Mo, W, Tc, and Re are extremely stable and do not oxidize alcohols on their own.
The highest metallates and oxides of the group 9 and 10 elements are quite rare, and information about
their reactivity with alcohols is missing in the literature.
Table 1.1. The standard electrode potentials (E
o
vs. RHE, V) for reduction of high-valent transition element
oxo and hydroxo complexes in alkaline (pH = 14, blue) and acidic (pH = 0, red) aqueous solutions and their
ability to oxidize alcohols and aldehydes.
V
V
/V
IV
–0.8/1.001
V
2
O
5
VO
4
3–
/H
2
O
2
(→ CHO)
Cr
VI
/Cr
III
–0.14/1.36
CrO
3
, Cr
2
O
7
2–
(→ CHO, COOH)
Mn
VII
/Mn
IV
0.53/1.692
MnO
4
–
, MnO
4
2–
(→ CHO, COO
–
)
Fe
VI
/Fe
III
0.71/2.09
FeO
4
2–

(→ CHO)
Co
III
/Co
II
0.20/1.92
Ni
III
/Ni
II
0.3/1.753
Cu
II
/Cu
I
–0.110/0.337
a
Cu(OH)
2

(CHO → COO
–
)
Nb
V
/Nb
IV
–1.2/–0.3
Mo
VI
/Mo
IV
–0.94/0.320
Mo
7
O
24
6–
/H
2
O
2
(→ R
2
CO)
Tc
VII
/Tc
IV
–0.46/0.738
Ru
VIII
/Ru
IV
0.54/1.48
RuO
4
, RuO
4
–
,
RuO
4
2–
(→CHO, COO
–
)
Rh
IV
/Rh
III
0.8/1.8
Pd
IV
/Pd
II
0.5/1.54
Pd
II
/Pd
0.1/0.983
Ag
I
/Ag
0.343/0.799
Ag
2
O
(CHO→COO
–
)
Ta
V
/Ta
IV
–1.6/–0.8
W
VI
/W
IV
–1.2/0.06
WO
4
2–
/H
2
O
2

(→ CHO, COOH)
Re
VII
/Re
IV
–0.61/0.510
Os
VIII
/Os
IV
0.108/1.02
OsO
4
,
OsO
2
(OH)
4
2–
(→ CHO, COO
–
)
Ir
VI
/Ir
IV
0.4/1.5
Ir
IV
/Ir
III
–0.7/0.4
Pt
IV
/Pt
II
0.15/0.91
Pt
II
/Pt
0.20/1.18
Au
III
/Au
0.600/1.50
Au(OH)
4
–
(→ COO
–
)
a
Since Cu
I
is unstable in acidic aqueous solution without special ligands, the red potential is given for
Cu
II
/Cu couple.
6
Oxidation with oxometallates has been known for more than a century, as these are among the most
studied and reliable of methods for alcohol to carboxylate conversion. While these have high rates and
mild conditions, they generate metal-containing waste, which makes them unfit for application at scale.
These stoichiometric methods are systematically surveyed here, because understanding the chemistry
available to the stoichiometric metal systems has enabled the community to convert many, and hopefully
many more going forward, to efficient catalytic systems.
Vanadium(V). Alcohol oxidation with vanadium oxidants has not attracted much attention from
organic chemists, however, it is known that reduction of vanadium pentoxide V
2
O
5
with ethanol in
aqueous sulfuric acid was utilized for the synthesis of [VO(H
2
O)
5
]SO
4
, where the organic by-product was
reported as acetaldehyde.
14
A vanadate-TEMPO catalytic system was used for benzyl alcohol oxidation to
benzaldehyde with hydrogen peroxide.
15
In this case, peroxovanadates, but not oxovanadate, VO
4
3–
, could
be responsible for the oxidation.
Chromium(VI). Many chromium(VI) reagents have been applied to oxidation of organic
compounds.
16,17
All of the alcohol-to- carboxylic acid transformations proceed under acidic conditions. In
organic synthesis, an aqueous acidic solution of Cr
VI
, Jones reagent, is typically prepared with chromium
trioxide CrO
3
or potassium dichromate K
2
Cr
2
O
7
and aqueous sulfuric acid.
18
The Jones method requires
acetone as a cosolvent to increase solubility of organic substrates and facilitate separation of the
carboxylic acid products from inorganic salts. With this method most primary alcohols are oxidized to
carboxylic acids, tolerating alkenes and alkynes.
19

The oxidation can also be done under neutral and non-aqueous conditions, following Corey-Schmidt
method, with pyridinium dichromate (C
5
H
5
NH)
2
Cr
2
O
7
in dimethylformamide at room temperature. Unlike
conjugated aldehydes, non-conjugated aldehydes are readily oxidized to carboxylic acids. Remarkably,
using dichloromethane instead of dimethylformamide selectively affords aldehydes, regardless of the
nature of substrate.
20,21
7
Oxidation with stoichiometric Cr
VI
reagents can be conveniently turned to catalytic fashion using
catalytic (2 mol%) amount of Cr
VI
and periodic acid, H
5
IO
6
, as a stoichiometric oxidant in wet acetonitrile
(E
o
(Cr
VI
/Cr
III
) = 1.33 V and E
o
(I
VII
/I
V
) = 1.567 V). This method successfully worked with catalysts such as
chromium trioxide
22
and pyridinium chlorochromate, (C
5
H
5
NH)CrO
3
Cl.
23
The method gives high yields
(> 95%) of aliphatic, benzoic, and dicarboxylic acids.
Molybdenum(VI) and Tungsten(VI). Solutions of Mo
VI
in dilute aqueous H
2
SO
4
are reduced to
“molybdenum blue” by furfurol or glucose, but not by simple alcohols, aldehydes, or even formaldehyde.
24

Although Mo
VI
and W
VI
do not oxidize alcohols on their own, their peroxo complexes do. For example,
peroxo complexes [M
VI
O(O
2
)
2
(2-PyCOO)]
–
(M = Mo and W) oxidize secondary alcohols directly in methanol
at 50
o
C, yielding up to 1.7 mol of ketone per mol of the complex.
25
Catalytic methods for secondary
alcohol oxidation were also developed that use ammonium heptamolybdate, (NH
4
)
6
Mo
7
O
24
· 4H
2
O,
26
or
sodium tungstate, Na
2
WO
4
· 2H
2
O,
27
as catalysts and aqueous hydrogen peroxide solution as an oxidant.
The peroxotungstate system can also oxidize primary alcohols to carboxylic acids under acidic conditions
when a phase-transfer catalyst is used, [NCH
3
(C
8
H
17
)
3
]HSO
4
. The yield of benzoic and octanoic acids by this
method is 87%.
28
Manganese(VII). Potassium permanganate, KMnO
4
, is widely used in organic synthesis,
29,30
generally
under basic conditions.
31
Oxidation under acidic conditions is less selective and is appropriate only for
simple alcohols; for example, 6-methyloctanoic acid (66%) was obtained during oxidation with KMnO
4
in
H
2
SO
4
solution at room temperature.
32
Under anhydrous and heterogeneous conditions solid sodium
permanganate, NaMnO
4
· H
2
O, can oxidize alcohols and aldehydes in refluxing hexane (69
o
C), giving, for
example, octanoic and benzoic acids with 67 and 81% yields, respectively.
33
KMnO
4
reacts with many
functional groups, such as C=C, C≡C, -NH
2
, -SH, -SR, -PR
2
. Moreover, permanganate can unpredictably
cleave unactivated C-H and C-C bonds, which limits the scope of its synthetic application.
34
Other issues
8
with KMnO
4
include its low solubility in organic solvents and resistance against further oxidation of some
intermediate aldehydes.
29,30
Iron(VI). The redox potential values suggest that ferrate(VI) ion, FeO
4
2–
, is more powerful oxidant
than MnO
4
–
, however nothing is known about its reactions with alcohols in aqueous media. Still, K
2
FeO
4

converts benzyl alcohol to benzaldehyde in pentane at room temperature in quantitative yield.
35

Evidently, oxidation of alcohols to carboxylates by ferrate(VI) could have unappreciated utility, since iron
is abundant and non-toxic.
Ruthenium(VIII, VII, and VI). Ruthenium tetroxide, RuO
4
, has many relevant synthetic applications.
36

It may be unfamiliar to some organic practitioners, because it’s typically generated in situ from RuCl
3
or
RuO
2
and an oxidant such as NaIO
4
, H
5
IO
6
, NaBrO
3
, NaClO, or Ca(ClO)
2
to manage its toxicity. RuO
4
is
incompatible with alkenes, alkynes, geminal diols, ethers, and compounds with activated methylene
group. Being a very powerful oxidizer it can cleave C-C bonds in aromatic compounds.
Upon reduction, RuO
4
forms lower oxo complexes: perruthenate (RuO
4
–
), as in the very successful
Ley reagent, and ruthenate (RuO
4
2–
), which can oxidize alcohols as well, but is less aggressive than RuO
4
.
Oxidation of alcohols to aldehydes in organic solvents by (n-Pr
4
N)RuO
4
(TPAP: the Ley reagent) proceed
catalytically (10 mol%) in combination with excess NMO · H
2
O in acetonitrile at room temperature to drive
the reaction further to carboxylic acids.
37
The yields of aliphatic and benzoic acids are high (70-94%),
however, 4-methyl- and 4-methoxybenzyl alcohols give only 26% and 32%, respectively.
38
Under these
conditions double and triple bonds are tolerated. TPAP can also be used as an electrocatalyst for
converting 1-butanol to butanal (34%), by applying a potential of 1.3 V in acetonitrile.
39
The most important synthetic applications of ruthenate, RuO
4
2–
, is oxidation of alcohols in alkaline
media to carboxylates or ketones.
40
In general, ruthenate does not oxidize alkenes or alkynes at room
temperature, for example, oct-7-en-2-ynoic acid was prepared from an alcohol with a good yield (74%)
using combination of RuCl
3
(1-2 mol%) and potassium persulfate, K
2
S
2
O
8
, in aqueous KOH solution.
41
9
Osmium(VIII and VI). Ethanol can be oxidized to acetate by osmium tetroxide (E
o
(Os
VIII
/Os
VI
) = 0.3 V,
pH = 14) in aqueous KOH solution.
42
The product of this reaction, K
2
[OsO
2
(OH)
4
], which itself can oxidize
ethanol in dilute HCl solution. Thus, in contrast to RuO
4
, OsO
4
does not react with alcohols under neutral
or acidic conditions. This makes it a useful and highly selective oxidant for functional groups other than
primary alcohols. Under anhydrous conditions benzyl alcohols are converted to aldehydes using catalytic
system OsO
4
/CuCl/pyridine and O
2
as a reoxidant.
43
Copper(II), Silver(I), and Gold(III). Complexes of Cu
II
with carboxylate ligands, such as [Cu(tartrate)
2
]
2–
,
[Cu(citrate)
n
]
m–
, and [Cu
2
(OAc)
4
(H
2
O)
2
] have been known since the 19
th
century as analytical reagents in
Fehling's,
44
Benedict’s,
45
and Barfoed’s tests
46
for discovery of reducing sugars and aldehydes. Typically,
the reaction is performed in aqueous hydroxide solution at moderate temperature (< 100
o
C), Cu
II
oxidizes
aldehydes to carboxylates forming a characteristic red precipitate of Cu
2
O, which serves as a positive
analytical signal. Silver carbonate (Ag
2
CO
3
) on Celite, known as Fetizon’s reagent, oxidizes alcohols to
aldehydes and ketones under neutral and anhydrous conditions in refluxing benzene, toluene, or
heptane.
47
Silver(I)-ammonia complex, Ag(NH
3
)
2
+
, is a primary component in Tollens’ reagent, which
selectively oxidizes aldehydes to carboxylates in aqueous hydroxide solution.
48
Silver oxide, Ag
2
O, in a
THF/H
2
O solution of NaOH was used for oxidation of a primary alcohol to carboxylate (90% yield) in the
total synthesis of polyunsaturated endiandric acid E.
49
Gold(III) in the form of Au(OH)
4
–
, generated in situ
from AuCl
4
–
and OH
–
, oxidizes ethanol producing solutions of colloid gold and acetate.
50
Nitrogen and Chlorine Based Oxidants. The use of stable organic aminoxyl radicals for the oxidation
of primary and secondary alcohols has been reviewed.
51
Aminoxyl radicals, such as TEMPO and its
derivatives 1 and 2 (Figure 1.2), can catalyze alcohol oxidation when sodium hypochlorite, NaClO, or
sodium chlorite, NaClO
2
, are used as stoichiometric oxidants. For example, 1 (1 mol%) works in a biphasic
system CH
2
Cl
2
/H
2
O, containing NaClO, NaHCO
3
, KBr, and [NCH
3
(C
8
H
17
)
3
]Cl. Primary alcohols are
quantitatively oxidized to aldehydes in a few minutes at 0 °C. Further oxidation to carboxylic acids is slow,
10
but the reaction is complete in a few minutes with the addition of catalytic amounts of phase-transfer
catalyst. All reactions are highly selective and applicable to aliphatic and benzyl alcohols (few examples,
87-96%).
52
Figure 1.2. Examples of catalysts for stoichiometric oxidation of alcohols to carboxylates.
Alternative method employs TEMPO (2-7 mol%) and NaClO (1-4 mol%) as catalysts, while NaClO
2

serves as an oxidant.
53
It seems that TEMPO together with NaClO oxidize an alcohol to an aldehyde, while
chlorite readily oxidizes the aldehyde to an acid without the assistance of TEMPO, regenerating
hypochlorite. The reaction is conducted in CH
3
CN/phosphate buffer (pH 7) at 35
o
C. The side-reaction of
aromatic chlorination is greatly suppressed because concentration of NaClO remains low throughout the
reaction. Yields of aliphatic, benzoic and chiral amino acids are above 85% (Scheme 1.2).
Scheme 1.2. Oxidation of chiral amino alcohols by TEMPO/NaClO/NaClO
2
system.
Comparisons between TEMPO/NaClO and TEMPO/NaClO/NaClO
2
catalytic systems suggest that the
later gives higher yields. However, this procedure is not applicable to unsaturated alcohols and substrates
with exceedingly electron-rich aromatic rings. The reaction can also be performed with polystyrene-
immobilized aminoxyl radical 2 (10 mol%).
54
N
H
Rh
PPh
3
N
H
Rh
N N
3 4
N
OMe
O
1
N
O
O
2
4
4
TEMPO (7 mol%)
NaClO, NaClO
2
N
O
O HO
Ph
N
O
O
HOOC
Ph
NHCbz
Ph OH
COOH
NHCbz
Ph
95%
85%
phosphate buffer
MeCN, 35
o
C
TEMPO (7 mol%)
NaClO, NaClO
2
phosphate buffer
MeCN, 35
o
C
A
A
11
1.4. Transfer Dehydrogenation
Transfer dehydrogenation methods are a much more appealing approach to accomplishing alcohol
oxidation than conditions that generate a stoichiometric metal waste stream. Even at the turn of this
century, Barry Trost was teaching graduate students that, although the stoichiometric metal-based
oxidation methods were essential to the development of organic synthesis, in the modern era of catalysis,
these should “disappear from use”.
Particularly regarding the conversion of primary alcohols, it’s important to note that there are a large
number of catalysts that will convert alcohols to esters, in a Tishchenko-like process. Such reactions
proceed through an intermediate aldehyde, which is in equilibrium with its hemiacetal (Scheme 1.3). The
latter is readily converted to an ester under dehydrogenation conditions. While this has been known for
a long time, there are relatively few examples of dehydrogenation methods that convert alcohols to
carboxylates or carboxylic acids directly. The Tishchenko-like ester formation pathway is a potential
reason for this. Another, more pressing issue is the Guerbet pathway: when an intermediate aldehyde is
generated under basic conditions, aldolization become possible. Unlike ester formation, once a C-C bond
is formed from an aldol, there’s no path backwards that enables formation of a carboxylate. We think that
this is a key reason why there have been few examples of catalytic conversion of alcohols to carboxylates
and why such reactions have special utility.
Scheme 1.3. Pathways of an aldehyde dimerization under the catalytic conditions.
Guerbet
dimerization
R
O
R
O
OH
R
R
R
R
OH
O
R
O
O
Tishchenko
dimerization
Aldol
reaction
base
base
R
OH
R
OH
[M-H]
[M]
R
[M]
[M]
12
Catalytic transfer dehydrogenation methods employ a catalyst and a hydrogen acceptor with
relatively low redox potential: alkenes, ketones, DMSO, or even O
2
. The catalysts typically involve
complexes of platinum group metals. For example, two very clever Rh
I
complexes containing a tridentate
diolefin amido ligand, 3 and 4 above, catalyze hydrogen transfer in aqueous hydroxide solution from
alcohols to acceptors like cyclohexanone, 1-hexene, and O
2
with the aid of a co-catalyst, Pd/C. The scope
of the method includes benzylic and aliphatic alcohols, diols, and glycerol.
55
These reactions enable the
synthesis of cinnamic acid (50%), 4-bromobenzoic acid (77%), and 3-furancarboxylic acid (84%). Alkenes
are partially hydrogenated under these conditions.
56
Aerobic oxidation of alcohols catalyzed by 4 (1 mol%)
was performed in an aqueous dimethyl sulfoxide solution of NaOH, where DMSO acts as a hydrogen
peroxide scavenger. Citronellol and geraniol were converted to the acids with 64% and 81% yields without
alkene hydrogenation (Scheme 1.4).
57
Remarkably, both catalysts 3 and 4 operate at room temperature
but 3 gives higher yields of the acids (up to 99%).
Scheme 1.4. Catalytic transfer dehydrogenation of citronellol and geraniol.
Oxidation of alcohols with O
2
takes place on the surface of various forms of metallic Pd, Pt, and Ru,
58

including Pd
59
and Pt
60
nanoparticles. These reactions are typically conducted in hot aqueous hydroxide
solution under 1 atm of O
2
, providing high yields of carboxylic acids (90-99%). The most popular version
of this method uses Pt/C (5-10 mol%), which is known as Heyns oxidation.
61,62
The catalyst loading is high,
but the system can be reused multiple times without noticeable loss of activity. Typically, the reaction
OH
COONa
OH
COONa
64%
81%
4 (1 mol%)
NaOH (1.2 eq.)
DMSO/H
2
O/THF
air, 25
o
C
4 (1 mol%)
NaOH (1.2 eq.)
DMSO/H
2
O/THF
air, 25
o
C
81%
81%
13
proceeds in a hot aqueous solution of NaHCO
3
. Water can be replaced with ethyl acetate, acetic acid, or
heptane, but in this case the products are aldehydes. These conditions allow selective oxidation of primary
alcohols in the presence of secondary alcohols.
1.5. Acceptorless Dehydrogenation
For the first time, primary alcohols were dehydrogenated directly to carboxylates without a catalyst
under forcing conditions in the 19
th
century by J. B. Dumas (1840) and later E. Reid et al. converted primary
alcohols to carboxylate salts and H
2
by heating with hydroxide at 350
o
C.
11
In the 21
st
century, it was found
that the reaction is catalyzed by compounds of transition metals, the corresponding methods are
summarized in Table 1.2. Under solvent-free conditions aliphatic and benzoic acids were prepared with
moderate to good yields (50-90%) at 150–160
o
C using pincer complexes of nickel and manganese, 5 and
6.
63,64
Complex 6 tolerates aryl halides, amines, alkenes, derivatives of pyridine and thiophene.
Furthermore, some particularly oxidatively-sensitive pharmaceutical agents were prepared with 6 in
moderate yields (Figure 1.3). Several methods utilize pincer complexes of manganese, iron, and cobalt,
7–9, in high-boiling hydrocarbon solvents, such as toluene (bp 111
o
C) and mesitylene (bp 165
o
C).
65,66
Figure 1.3. Pharmaceutical agents synthesized from alcohols using complex 6.
Surprisingly, such simple compounds as silver carbonate
67
and zinc oxide
68
enable this reaction as
well. In the latter case, hydrogenation of alkenes and aryl halides were detected as side reactions.
O
O
COOH
F F
46%
Precursor of
Roflumilast
COOH
S
S
51%
Lipoic acid
COOH
O
60%
Adapalene
O
HO
COOH
64%
Vanillic acid
A
A
14
Table 1.2. Characteristics of catalytic acceptorless dehydrogenation methods.
Catalyst
(mol%)
Conditions T,
o
C
Aliphatic
Acids, %
Benzoic
Acids, %
5 (1.0) RONa, neat 150 40 60-90
6 (0.2) NaOH, 2 eq. H
2
O, 16 h 160 54-95 61-90
7, 8 (2.0) KOH, toluene, Ar 120 NMR >99 –
9 (2.0) KOH, toluene, 16 h 140 67-86 67-95
10 (0.5) NaOH, H
2
O, 12 h 100 – 86-95
Ag
2
CO
3
,
MnBr
2
(2.5)
KOH, mesitylene, 8 h 165 59-91 58-94
ZnO (20) KOH, mesitylene, 18 h 164 67-82 60-91
Pd/C (5.0) NaOH, H
2
O, 800 hPa 80 84 66-99
Rh/C (20) NaOH, H
2
O 60-100 81 –
Catalytic carboxylate synthesis by acceptorless dehydrogenation in an aqueous hydroxide solution
requires mild reaction conditions (60–100
o
C, 1 atm) and can be achieved using heterogeneous palladium
and rhodium
12
catalysts and homogeneous dirhodium catalyst 10.
69
The main side reactions here are aryl
halide reduction and decarbonylation of substrate alcohols. For example, Pd/C converts 4-chlorobenzyl
alcohol to benzoic acid (55%) within six hours, and Rh/C turns 6-phenylhexanol-1 to 1-phenylpentane
(13%). Dehydroxymethylation of alcohols results from a background catalytic decarbonylation of
intermediate aldehydes, which is a typical reaction in chemistry of platinum group metals.
Ruthenium. Complexes of ruthenium bearing mono-, di-, and tridentate ligands are the most
abundant group of catalysts for acceptorless dehydrogenation of alcohols to carboxylates (Figure 1.4).
N Co
NHBu
t
NHBu
t
Br
Br
6 7
8
9 5
10
N Ni
NEt
2
NEt
2
Cl
Cl
N Mn
PPr
i
2
PPr
i
2
CO
CO H
Br
N Mn
PPr
i
2
PPr
i
2
CO
CO
N Fe
PPr
i
2
PPr
i
2
HBH
3
CO H
H
Cl
N Rh
N
N
N Rh
N
N
O O
Cl Cl
6
6
15
The reaction conditions of ruthenium-based catalytic methods are summarized in Table 1.3. Depending
on the ligand structure, the catalysts operate in hydrocarbons, water, or neat. Despite the importance of
the ruthenium coordination environment for enabling the catalytic activity, the ligand structure seems to
have almost no effect on ruthenium performance among the systems outlined in Table 1.3.
Figure 1.4. Examples of ruthenium catalysts for acceptorless dehydrogenation of alcohols to carboxylates.
Complex 11 gives the best yields of benzoic acids (84%) under solvent-free conditions at 150
o
C, while
the reaction is slow in refluxing aqueous hydroxide solution (37% isolated benzoic acid after 24 h reaction,
82% – after 72 h).
70
In the presence of two equivalents of water, 12 gives 2-(dimethylamino)acetic acid
with 74% yield. The catalytic system is air tolerant and can be recycled up to five times.
71
A group of
complexes with a general formula [RuCl
2
(p-cymene)(NHC)], 13-15, demonstrated its efficiency in alcohol
dehydrogenation, however, while 13 operates in water by itself,
72
complexes 14 and 15 are active in
toluene and require tricyclohexylphosphine and the carbene ligand additives, respectively.
73,74
Although
complex 13 does not tolerate alkenes and amino alcohols, it dehydrogenates diols to diacids with
21
N
Ru
MeCN
NCMe
20
X
N
H
N
H
N
N
11 (X = Cl, OTf)
22 26 (R = H)
12 (R = Me)
Cl
Ru
Cl
N
N
Pr
i
Pr
i
14
Cl
Ru
Cl
N
N
R'
R
23
N
Ru
Cl
CO
PPh
3
PPh
3
17
Ph
2
P
P
Ph
2
Ru
L
L
L
N N
N
18
N N
Ru
24
N
O
O
Ru
CO
CO
OC
Ru
OC
Ru
O
O
N
OC CO
OC CO
25
X
X
N Ru
PPh
2
PPh
2
Cl
CO R
H
N Ru
PBu
t
2
PBu
t
2
H
H
H
2
N Ru
H
CO
Cl
PBu
t
2
N
N Ru
PBu
t
2
PBu
t
2
H
CO
H
N
N
Ru
H
CO
PPh
3
PPh
3
N
H H
Cl
Ru
NH
2
N
16
N
Ru
PPh
3
Cl
Cl
N N
HN NH
Mes Mes
13 (R = R' = hexyl, X = H)
15 (R = Me, R' = Et, X = Cl)
19
19
19
16
moderate yields (59-63%). Other complexes that operate in refluxing toluene are 16-19.
75-78
Complex 18
is generated in situ from [RuCl
2
(COD)]
n
and a tridentate diphosphinocarbene ligand, the fac-coordination
of the ligand is suggested by
31
P NMR data in a toluene solution.
77
The yields of carboxylic acids vary from
moderate to high. Unfortunately, the catalytic systems enabled by 14-18 suffer from partial reductive
dehalogenation of benzoic acid products. For example, in dehydrogenation of 4-chlorobenzyl alcohol
catalyzed by 15, 4-chlorobenzoic and benzoic acids were isolated with 70% and 10% yields. Hydrogenation
of unsaturated functional groups is another common side reaction for ruthenium catalytic systems and
was detected in case of 14, 18, and 19. It is remarkable that alkenes are tolerated by 15, as well as primary,
secondary, and tertiary amines.
74
Table 1.3. Characteristics of ruthenium-catalyzed acceptorless dehydrogenation methods.
Catalyst
(mol%)
Conditions T,
o
C
Aliphatic
Acids, %
Benzoic
Acids, %
11 (0.2) CsOH, neat, 24 h 150 70 57-84
12 (0.1) NaOH, 2.0 eq. H
2
O, 3 h 130 25-96 10-90
13 (1.0) NaOH, H
2
O, 24 h 100 52-92 45-91
14 (1.0) PCy
3
, NaOH, toluene, 6 h 120 51-88 49-88
15 (0.0125) NHC, KOH, toluene, 12 h 120 56-95 52-92
16 (2.0) KOH, toluene, 6 h 110 20-80 39-86
17 (0.5) KOH, toluene, 6 h 120 50-68 45-89
18 (1.0) NHC, KOH, toluene, 24 h 120 55-98 68-95
19 (0.2) KOH, toluene, 18 h 120 65 79-89
20 (0.2) NaOH, H
2
O, 18 h 100 61-88 83-99
21, 22 (1.0) NaOH, H
2
O, 20 h 100 32-92 85
23 (5.0) NaOH, H
2
O, 6-24 h 100 59-99 62-99
24 (0.5) KOH, H
2
O, toluene, 48 h 120 68 75
25 (1.0) NaOH, H
2
O, 2-propanol, 12 h 98 19-34 25-71
Acceptorless dehydrogenation of primary alcohols is often performed in an aqueous hydroxide
solution due to conveniently low boiling point of water and its utility for the product isolation. Complexes
with PNN and PNP pincer ligands 20-22 were employed for this purpose. Complex 20 was successfully
used for oxidation of diols to give glutaric (61%) and isophthalic acids (99%). Unsaturated alcohols are
17
partially hydrogenated, for example, cinnamyl alcohol gives only 24% of cinnamic acid, and 44% of
hydrogenated by-products. Primary amines are not tolerated, as 4-aminobutanol-1 gives 2-pyrrolidone
(85%).
79
It was shown that catalysis by ruthenium tetrahydride 22 begins with decarbonylation of a
primary alcohol that generates the active catalyst 21, which, in general, enables higher yields of
carboxylates than precursor 22.
80
Complexes 23 demonstrated its utility in a highly valuable
transformation of unprotected amino alcohols to amino acids (Scheme 1.5). The structure of amino
alcohol determines the reaction chemoselectivity, in particular, high stability of a five-membered ring
favors the formation of 2-pyrrolidone from 4-aminobutanol-1 rather than 4-aminobutyrate.
81
Scheme 1.5. Catalytic dehydrogenation of amino alcohols by complex 23.
While the majority of ruthenium catalysts are derivatives of Ru
II
, a complex of zero-valent ruthenium
24 and a mixed-valent triruthenium cluster 25 are the two exceptions. Satisfactory performance of 24 was
demonstrated on a few substrate alcohols, including propylene glycol that gives lactic acid with 55%
yield.
82
Complex 25 exhibits poor catalytic activity as suggested by the low yields of acids.
83
Complex 26 (Ru-MACHO) dehydrogenates polyols such as ethylene glycol, glycerol, and sorbitol with
KOH in diglyme at 125
o
C. Based on NMR data, 2.5 ppm of 26 convert glycerol to lactate with 67% yield
within 24 h (Scheme 1.6). Sometimes propylene glycol forms as a major side-product.
84
78%
99%
OH
NH
2
COONa
NH
2
NH
2
OH
COONa
NH
2
OH
H
2
N
H
N
O
86%
23 (5 mol%)
NaOH, H
2
O
110
o
C
23 (5 mol%)
NaOH, H
2
O
110
o
C
23 (5 mol%)
NaOH, H
2
O
110
o
C
78%
78%
18
Scheme 1.6. Dehydrogenation of glycerol to lactate by ruthenium and iridium catalysts.
Iridium. A series of iridium compounds were studied as catalysts for glycerol dehydrogenation to
potassium lactate, among them commercial heterogeneous (Ir/C, IrO
2
, IrCl
3
) and homogeneous catalysts
([Cp*IrCl
2
]
2
, [IrCl(COD)]
2
, [IrCl(CO)
2
]
2
), as well as complexes with 1,3-dimethylimidazol-2-ylidene ligand, for
example, mono- and bis-carbene derivatives: [IrCl(COD)(NHC)], [IrCl(CO)
2
(NHC)], and 27-29 (Scheme
1.6).
85
It was established that bis-carbene complexes 27-29 possess superior catalytic activity among the
series and is characterized by the following turnover numbers: 30100 (27), 2400 (28), and 4760 (29). The
highest conversion of glycerol is 94% and it was reached with 0.036 mol% of 27 within 24 hours at 115
o
C.
Selectivity toward lactate varies within 63-95% due to formation of potassium formate, ethylene and
propylene glycol as major side products. The selectivity issue was resolved in a catalytic system based on
pyridine-carbene complex 30, which shows even higher efficiency (TON = 4.56 x 10
6
and TOF = 4 x 10
4
h
–
1
).
86
Coordination polymer 31 exhibits high catalytic activity with TON = 1.24 x 10
5
at 5 ppm iridium loading
and can be recycled up to 31 times.
87
Hydrogen evolution from glycerol and NaOH in diglyme at 125
o
C
was detected in the presence of pincer complex 32, however the catalytic system was not well studied.
84
[Ru] or [Ir]
KOH
115-160
o
C
OH HO
OH
OH
OK
O
OH
OH
H
2
+ +
A
A
19
Figure 1.5. Examples of iridium catalysts for acceptorless dehydrogenation of alcohols to carboxylates.
The first claimed iridium catalyst for conversion of benzyl alcohols to benzoic acids, complex 33,
appeared in 2017, This system enables good yields (60-88%) of benzoic acids in neutral boiling water
within 20 hours.
88
We find this report unreliable, since spontaneous dehydrogenation of alcohols is
possible only in the presence of a base, as we showed previously in section 2. This particular case was
explained in detail by Papish and Brewster in recent follow-up work.
89
Nevertheless, acceptorless
dehydrogenation of aliphatic, benzylic, heterocyclic, and amino alcohols was reported with a pyridine-
phosphine complex 34, that operates in refluxing toluene in the presence of stoichiometric amount of
KOH.
90
The yields of acids vary within 40-98% and strongly depend on the structure of alcohol, for
example, functional groups as aryl bromides and iodides, alkenes, and nitro arenes are incompatible with
the catalyst because of uncontrolled hydrogenation. This substrate scope limitation demonstrates a close
analogy between iridium- and ruthenium-based catalytic systems, which is probably a consequence of the
similarity between isoelectronic Ru
II
and Ir
III
, which appear to be common oxidation states for driving the
dehydrogenation catalytic cycles. Mechanistic studies show that precatalyst 34 undergoes a highly
complex series of transformations before it turns to the active catalyst 36 (Figure 1.5). The key steps
34
N
Ir
P
Ir
CO
PBu
t
2
H
H
N
H
Ir
P
H
N
35 36
ROH
KOH
ROH
KOH
25
o
C 110
o
C
Ir
N
H
2
O
N
N
HO
2+
Ir
N
N
33
30
HN Ir
PPr
i
2
PPr
i
2
Cl
H
H
32
N
N N
N
Ir
OC
CO
n
Ir
N
N
L
L
N
N
Ir
Cl
N
N
29
N
N
27 (L = CO)
28 (L
2
= COD)
31
N
Ir
P
N
Bu
t
Bu
t
29
29
20
involve β-hydride elimination and isomerisation of COD ligand, to give 35, followed by aldehyde
decarbonylation and ortho-metallation of the pyridine ring. This example demonstrates that rationalizing
catalytic activity based on precatalyst structure without knowing the structure of catalytic species can be
misleading. Although the mechanisms of ruthenium and iridium catalyst activation in acceptorless alcohol
dehydrogenation are generally poorly understood, it is evident that a combination of phosphine, carbene,
and carbonyl ligands in the coordination environment of the metals raises the chance of manifesting the
catalytic activity.
1.6. Electrochemical Methods
Anodic oxidation of aliphatic alcohols to aldehydes, ketones, acids, and esters has been well-
reviewed.
91,92
The material balances of alcohol electrooxidation and acceptorless dehydrogenation are
identical, since none of them needs a stoichiometric oxidant. However, during electrolysis generation of
dihydrogen and carboxylate/acid is separated in space; and since the reaction is driven by the external
voltage, the limitations of acceptorless dehydrogenation, associated with positive Δ
r
G
o
in neutral and
acidic solutions, do not apply for electrochemical methods. For example, anodic oxidation of 1-hexanol in
5% aqueous H
2
SO
4
at 12
o
C gives hexanoic acid (17%) and n-hexyl hexanoate (17%). Electrolysis was
conducted at current density of 11 mA/cm
2
and current efficiency of 60% (with respect to acid) using lead
cathode and lead dioxide coated anode.
93
Still, majority of the reported electrochemical methods utilize alkaline aqueous solutions.
Electrosynthesis of acetate, propionate, and butyrate from the corresponding alcohols was accomplished
on a nickel oxide anode (1M KOH, 50
o
C, 10 mA/cm
2
).
94
Electrolysis with nickel hydroxide anode and steel
cathode enables efficient synthesis of carboxylates in the presence of alkenes, alkynes, and heterocycles
(1M NaOH, 25
o
C, 16 mA/cm
2
, 2.0 V).
95
For example, benzoic (86%), propiolic (51%), butyric (92%), and 2-
furancarboxylic acids (79%) were obtained this way. Oxidation of ethanol to acetaldehyde, and then to
21
acetate was reported using a redox couple [Ru
IV
O(bipy)
2
Py]
2+
/[Ru
II
(H
2
O)(bipy)
2
Py]
2+
as electrocatalytic
system in hydrophosphate buffer (pH = 7, 50
o
C, 0.8-1.0 V).
96
Recently, another electrocatalytic method
was developed that uses aminoxyl radical 37 as a catalyst, thus enabling highly efficient synthesis (83-99%
yields) of aliphatic and benzoic acids, pyridine and quinoline carboxylic acids, and chiral derivatives of
amino acids (Scheme 1.7). The reaction is conducted in carbonate buffer (pH = 10, 0.9 V) and it is the best
electrooxidation method known up to date.
97
Scheme 1.7. Electrosynthesis of an amino acid derivative.
1.7. Outlook
There are numerous methods for oxidation of primary alcohols to carboxylic acids, yet many
practicioners prefer to use stoichiometric methods, due to their reliability, short reaction times, and low
cost. The historically recent discovery of catalytic acceptorless dehydrogenation methods has
demonstrated the utility and a potential of this approach. However, certain acceptorless dehydrogenation
conditions can suffer incompatibility with certain functional groups, such as alkenes, alkynes, aryl halides,
and esters in cases, probably, because of the high reduction potential of transient metal hydrides and
strongly alkaline reaction conditions that are present in the cycle. Resolving the issue would make these
methods more commonly practiced in synthetic organic chemistry. Electrochemical oxidation of primary
alcohols is not yet studied extensively, but anodic oxidation is more versatile than chemical oxidation since
it gives options to control the process by tuning the voltage, current density, pH, and anode material. The
available data suggest that the substrate scope of the electrolytic methods is broader than that of
37 (5 mol%)
OH
N
O
COONa
N
O
91%, 92% ee
(40 g scale)
N
O
NHAc
Electrolysis at 0.7 V vs. AgCl/Ag
NaHCO
3
, H
2
O
22
acceptorless dehydrogenation, since these typically tolerate alkenes, alkynes, heterocycles, and amino
alcohols. Electrolysis is easily neglected by synthetic chemists, though, because of the requisite
infrastructure of apparatus, buffers, etc.
Returning to Barry Trost’s advice to graduate students 20 years ago, stoichiometric methods for
alcohol oxidation probably should disappear from use in the 21
st
century in order to facilitate more
sustainable production of bulk and fine chemicals. Enabling this transition will require continued work
from the catalysis and electrochemical communities to enable more ideal syntheses:
98
we should focus
on simple, mild operating conditions, tolerance of highly functionalized alcohol targets, and careful
studies of selectivity in challenging molecular contexts.
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33
Chapter 2. Iridium Catalysts for Acceptorless Dehydrogenation of Alcohols to
Carboxylic Acids: Scope and Mechanism
2.1. Introduction
This chapter duplicates a manuscript that was published in ASC Catalysis in 2018 (Cherepakhin, V.;
Williams, T. J. Iridium Catalysts for Acceptorless Dehydrogenation of Alcohols to Carboxylic Acids: Scope
and Mechanism. ACS Catal. 2018, 8, 3754–3763).
Oxidation of primary alcohols to carboxylic acids is a quintessential transformation in organic
chemistry, historically accomplished with a stoichiometric portion of a metal-based oxidant, such as
potassium permanganate,
1,2
chromium(VI) oxide,
3
pyridinium dichromate,
4
RuCl
3
/NaIO
4
,
5
sodium
hypochlorite,
6
or the like. These evolved, ultimately to culminate in Lindgrin (and related) oxidation of
aldehydes, the mild conditions of choice for complex molecule synthesis. Still, some forcing conditions to
dehydrogenate primary alcohols directly to carboxylates have been known since the 19
th
century. For
example, J. B. Dumas and later E. Reid et al.
7
converted primary alcohols to carboxylate salts and H
2
by
heating with hydroxide at 350
o
C. This approach has recently advanced to emerge as an elegant 21
st
-
century replacement for the stoichiometric oxidant methods, which is important, because alcohol to
carboxylate conversion remains a frequent operation in complex molecule synthesis.
8–11
Carboxylate synthesis by acceptorless dehydrogenation presents a graceful approach with the recent
development of new catalytic conditions, some enabling the reaction under very convenient conditions
(25 – 120
o
C, 1 atm). To date, homogeneous catalysts for this reaction include systems based on rhodium,
ruthenium, and recently one iridium complex. The former includes a diolefin amido tridentate ligand and
catalyze hydrogen transfer from alcohols to acceptors like cyclohexanone,
12
1-hexene,
13
or O
2
/DMSO.
14

Ruthenium complexes featuring tridentate PNN,
15
PNP,
16
and NHC-ligands,
17a
catalyze acceptorless
dehydrogenation. The Cp*Ir
III
system enables reactions in neutral water.
17b
The former reactions take
34
place in boiling NaOH solutions and give high yields of aliphatic carboxylates and benzoates. Such
reactions also are possible in refluxing toluene
18
or neat alcohol (150
o
C).
19
Very robust catalysts for acceptorless dehydrogenation of formic acid (based on 2.2, Figure 2.1)
20

and glycerol (2.1, 2.4) were reported recently.
21
The latter gives an example of excellent selectivity for
primary alcohol oxidation in the presence of other molecular complexity. This study shows that these
iridium-based systems enable a method for acceptorless dehydrogenation of primary alcohols to
carboxylic acids. This method gives good yields of many carboxylates and enables selectivity that is difficult
to achieve with other catalytic systems. A broad substrate scope was demonstrated, including reactions
of alcohols with a secondary amino group or aryl halide. Particularly, the study shows details of catalyst
initiation and provides a unifying proposal of the mechanisms of catalyst activation that govern the
disparate reactivities of 2.1 and 2.2, respectively in glycerol and formic acid dehydrogenation.
Figure 2.1. Iridium complexes 2.1 – 2.5.
2.2. Results and Discussion
2.2.1. Alcohol Oxidation
The discovery and optimization of our reaction is outlined in Table 2.1. The material balance of the
reaction involves one equivalent of hydroxide. However, any base in the reaction will cause a parallel
Guerbet self-condensation.
7
For example,
22
neat 1-octanol converts to potassium octanoate (72%) and 2-
octyl-1-octanol (28%) in the presence of 1 eq. of potassium hydroxide and 2.1 (1 mol%) at 150
o
C (yields
calculated by NMR). In order to suppress this side-reaction, the dehydrogenation was conducted in a
solvent of refluxing toluene: here, 1-octanol gives 99% of octanoate and 1% of Guerbet alcohol after 40
Ir
P
N
R R
Ir
N
N
CO
CO
Mes
N
Ir
Cl
Cl
Ir Ir
N
N
N
OTf
X OTf
2.1 2.4
2.5
2.2 (R = t-Bu, X = OTf)
2.3 (R = Ph, X = Cl)
35
h. This solvent choice contrasts many examples of primary alcohol dehydrogenation in the literature,
15–17

in which reactions are typically run in water. Complex 2.1 is less effective in an aqueous medium, and the
yield of octanoate is only 7% after 40 h. The origin of selectivity for carboxylate formation appears to be
solubility: hydroxide’s limited solubility in toluene limits the total base concentration available for the
Guerbet side reaction. Toluene is useful for most alcohols; diols and triols have limited solubility, and thus
limited reactivity.
Table 2.1 shows the performance of the iridium pre-catalysts in alcohol dehydrogenation in toluene.
The most effective catalyst, typically 2.1 or 2.2 in different cases, was determined among available
iridium(I) complexes (Figure 2.1) on the basis of product yield and selectivity. 1-Butanol, 1-octanol, and 1-
hexadecanol were used as substrates. The selectivity for carboxylate synthesis decreases with increased
molecular weight of the alcohol, which we believe to be an effect of base solubility.
Table 2.1. Selectivity screening of catalysts 2.1 – 2.5.
a
Entry [ Ir ] R Carboxylate, % Guerbet Alcohol, %
1 2.1 Ethyl > 99 0
2 2.2 Ethyl > 99 0
3 2.1 n-Hexyl 99 1
4 2.2 n-Hexyl 95 5
5
b
2.1 n-Tetradecyl 90 10
6 2.2 n-Tetradecyl 92 8
7 2.3 n-Tetradecyl 77 23
8 2.4 n-Tetradecyl 77 23
9 2.5 n-Tetradecyl 76 24
a
Reaction conditions: a mixture of alcohol (2.1 mmol), KOH (2.4 mmol), catalyst (2.1 x 10
-5

mol, 1 mol%), and toluene (4 mL) was stirred at reflux for 37 h (oil bath, 120
o
C). The yields
were derived from
1
H NMR spectra in CD
3
OD.
b
0.1 mol% of 2.1 was used.
Relative rates of catalysis for complexes 2.1, 2.2, and 2.5 were evaluated by recording hydrogen
evolution in the conversion of benzyl alcohol to benzoate. Benzyl alcohol was chosen to avoid a Guerbet
R
OH
OK
R
O
KOH (1.1 eq.), [ Ir ]
Toluene, reflux, 37 h
+
OH
R
R
36
reaction. Kinetic profiles of hydrogen evolution demonstrate that complex 2.2 has the highest catalytic
activity (Figure 2.2). Though 2.2 proved to be the fastest catalyst among the iridium compounds, complex
2.1 was also examined in substrate scope studies.
Figure 2.2. Hydrogen evolution profiles of benzyl alcohol dehydrogenation with 2.1, 2.2, and 2.5. Reaction
conditions: a mixture of catalyst (4 x 10
-6
mol, 0.2 mol%), KOH (2.2 mmol), benzyl alcohol (2.0 mmol), and
toluene (10 mL) was actively stirred at reflux (oil bath, 120
o
C).
Application of the optimized reaction conditions enabled an effective conversion of a variety of
primary alcohols to potassium carboxylates (Table 2.2). Substrate scope includes aliphatic alcohols
(entries 1 – 5), benzylic alcohols (entries 6 – 12), and even heteroatom functionalized systems like
thioethers (entry 8), amino alcohols (entries 13 and 14), and heterocycles (entries 16 and 17). This latter
class of substrates is unknown for other catalytic systems for this reaction, including the one based on
iridium.
Several generalizations can be drawn from these data. Unfunctionalized alkyl systems proceed
smoothly (entries 1 – 3), and an adjacent strained ring is not derivatized in the reaction (entry 4). Sterically
bulky systems can be problematic. For example, entries 5 and 18 demonstrate that a 1-adamantyl
37
substituent slows the reaction, ca. half the rate, although it reaches completion. A doubly-blocked 2,6-
dimethylbenzyl alcohol is unreactive.
Although aryl bromides and iodides are only moderately tolerated, entries 10 and 11 give examples
of Ar–Br and Ar–I bonds surviving alcohol dehydrogenation conditions. Reduction of Ar–Hal to Ar–H is the
major side reaction in these cases.
18
For example, 4-bromobenzyl alcohol undergoes dehydrogenation to
form both the corresponding 4-bromobenzoate (58%) and the reduced benzoate (9%) product. 4-
Iodobenzyl alcohol afforded a larger amount of dehalogenated benzoate (32%) in addition to the
halogenated product (42%). In contrast to aryl bromides and iodides, aryl chlorides are well tolerated
(entry 9), and afford access to a growing number of metal-catalyzed coupling reactions.
23
Secondary amines and azoles are tolerated. Since several iridium complexes catalyze alkylation of
primary amines with alcohols,
24a,25
amino alcohols were tested as substrates as well. For example, 2-
(ethylamino)ethanol converts efficiently to ethylaminoacetate without polymerization or other side
reactions. This presents an unprecedented approach to amino acid synthesis. It was found that
intramolecular oxidative cyclization of amino alcohols is possible: dehydrogenation of 2-(2-
aminophenyl)ethanol results in cyclization, yielding indole exclusively.
24b
A good selectivity was observed for carboxylate synthesis in cases where arene hydrogenation or
reductive decarboxylation can take place. For example, 1-naphthalenemethanol gives a high yield (84%,
entry 12) of 1-naphthoic acid, however, trace quantities of naphthalene, 1,2-dihydronaphthalene, tetralin,
and potassium formate were detected in the reaction mixture. 2-Quinolinemethanol is even more
susceptible to over-reduction, yet only a trace of the corresponding tetrahydroquinoline was observed in
the crude product mixture (entry 17). By contrast, an attempt to dehydrogenate 2-thiophenemethanol
and 3-phenylpropargyl alcohol resulted in product decarboxylation, giving potassium formate.
Unfortunately, alkenes and nitro compounds are incompatible with our conditions and undergo
uncontrolled reduction.
38
Table 2.2. Substrate scope for dehydrogenation of primary alcohols using pre-catalysts 2.1 and 2.2.
a
Entry Alcohol Product
Catalyst
Time (h)
Isolated yield (%)
1
2a
2.1 (0.2%)
40
96
2
2b
2.1 (0.2%)
40
90
3
2c
2.1 (0.2%)
40
85
4
2d
2.2 (0.2%)
40
81
5
2e
2.2 (0.4%)
75
77
6
2f
2.2 (0.2%)
40
98
7
2g
2.1 (0.1%)
36
79
8
2h
2.1 (0.1%)
40
74
9
2i
2.2 (0.1%)
20
80
10
2j
2.1 (0.1%)
15
40
11
2k
2.2 (0.3%)
18
42
R OH
1. [ Ir ], KOH, toluene,
reflux
R
O
OK
R
O
OH 2. HCl, H
2
O
or
+ 2H
2
OH
CO
2
K
OH
CO
2
K
OH
CO
2
K
OH
CO
2
K
OH
CO
2
H
OH
CO
2
H
OH
MeO
CO
2
H MeO
OH
MeS
CO
2
H MeS
OH
Cl
CO
2
H Cl
OH
Br
CO
2
H Br
OH
I
CO
2
H I
39
12
2l
2.2 (0.2%)
40
84
13
2m
2.2 (0.2%)
40
82
14
2n
2.2 (0.2%)
13
80
15
2o
2.2 (0.2%)
40
80
16
2p
2.1 (0.2%)
20
63
17
2q
2.2 (0.2%)
40
65
18
2r
2.1 (0.1%)
15
0
a
Reaction conditions: a mixture of alcohol (2.0 mmol), KOH (2.2 mmol), catalyst, and
toluene (10 mL) was stirred at reflux.
The catalytic systems can be applied to large-scale synthesis of carboxylic acids. Complexes 2.1 and
2.2 convert benzyl alcohol to benzoic acid with turnover numbers 16400 and 40600 respectively. Pre-
catalyst 2.2 loading can be as low as 50 ppm to give up to 15 g of benzoic acid. Moreover, precipitation of
the carboxylate during the reaction enables easy separation of the product by simple filtration. The
catalyst-containing toluene solution can then be reused.
The catalytic method presented here is the second example we know for iridium based primary
alcohol dehydrogenation. The previously reported method by Fujita utilizes iridium(III) pre-catalyst
[Cp*Ir(NC)(H
2
O)](OTf)
2
(NC = pyridylcarbene bidentate ligand).
17b
An advantage of the method is the
possibility to conduct alcohol oxidation under base-free conditions, whereas our method requires
OH
CO
2
H
N
H
OH
N
H
CO
2
K
NH
2
OH
N
H
OH
CO
2
H
N
OH
N CO
2
K
N
OH
N CO
2
K
OH
CO
2
H
40
stoichiometric KOH. Fujita’s method uses high catalyst loading (2 – 5 mol%) and the reaction scope is
confined to simple benzyl alcohols, with reactions of aliphatic alcohols giving yields of <25%. Thus, our
method is a useful complement to the Fujita’s chemistry.
2.2.2. Mechanism
The near-interchangeability of 2.1 and 2.2 in the conversions of alcohols to carboxylic acids was not
anticipated. These species have very different reactivity in glycerol
21
and formic acid
20
dehydrogenation:
2.1 works only in the former and 2.2 only in the latter. Thus, carboxylate synthesis provides a platform
from which to run comparative stoichiometric reactions of 2.1 and 2.2 (Scheme 2.1) to gain insight into
both the mechanisms of catalyst initiation and the differences in their reactivities.
Complex 2.1 reacts with neat 4-methoxybenzyl alcohol in the presence of potassium hydroxide to
form iridium(I) alkoxide complex 2.6, which can be extracted from potassium salts with C
6
D
6
. The structure
of 2.6 was established by NMR, with the coordination geometry assigned by NOE analysis (Figures 2.22 –
2.25). The complex retains its bidentate N—C ligand without proton loss, and the coordinated alkoxide
ligand exchanges slowly (k ~ 1 s
-1
) with excess of the alcohol in solution. Complex 2.6 is reactive in benzene
solution in the presence of excess 4-methoxybenzyl alcohol, converting it to 4,4’-dimethoxybenzyl
benzoate. The iridium-containing species precipitates from solution leaving cyclooctene. These data are
consistent with hydrogen transfer from the alcohol to coordinated 1,5-cyclooctadiene to give reduction
of one its olefins. The same reactivity of 2.1 was observed in glycerol dehydrogenation.
21
Importantly, we
see no evidence of an iridium hydride or any other metallic intermediate in this sequence.
41
Scheme 2.1. Reactions of complexes 2.1 and 2.2.
Complex 2.2 reacts with 4-methoxybenzyl alcohol or isopropanol in the presence of KOH to give
iridium(III) complex 2.7 (Scheme 2.1), which can be isolated in 64% yield. The structure of 2.7 was
established by single-crystal X-ray diffraction (Figure 2.3). It is analogous to the structure of [IrH(η
1
,η
3
-
C
8
H
12
)(dppm)], reported by Werner and co-workers.
26
An intermediate iridium alkoxide is probably
involved in the formation of 2.7, but unlike 2.6, this converts to a stable iridium hydride species.
Figure 2.3. Molecular structures of 2.7 (left) and 2.8 (right) shown with 50% probability ellipsoids.
Hydrogen atoms are omitted for clarity, except for localized hydrides.
Ir
O
OMe
2.6
2.1
2.7 (64%)
KOH, C
6
H
6
, RT
2.2
OH
Ir
P
H
N
tBu
tBu
toluene, reflux
KOH, 1-butanol
2.8 (63%)
Ir
N
N
N
OTf
N
N
N
Ir
P
N
tBu tBu
OTf
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
tBu
tBu
H
KOH, C
6
D
6
, RT
MeOC
6
H
4
O
O C
6
H
4
OMe
+
cyclooctene
MeO
OH
42
Complex 2.2 reacts with 1-butanol and potassium hydroxide in boiling toluene to form dinuclear
iridium(III) complex 2.8 (Scheme 2.1), which is isolated in 63% yield. Its structure, shown in Figure 2.3, has
two notable features: a single CO ligand and a bridging ortho-metalated pyridine fragment. The CO ligand
derives from n-butanal,
27–30
and several cases of pyridine ortho-metalation by iridium complexes have
been described.
31–33

1
H NMR of 2.8 shows three hydride ligands; their arrangement in the coordination
sphere was confirmed by COSY, NOESY/EXSY, and
1
H –
31
P HMBC experiments (Figures 2.31 and 2.39).
Complex 2.8 is stable in the solid state and in solution at room temperature in the absence of air,
however it undergoes reversible isomerization to 2.10 in toluene at 110
o
C (Scheme 2.2). According to
1
H
NMR data, heating the solution of pure 2.8 leads to disappearance of the two cis-hydride signals and
reduction of types of tert-butyl groups from four to two. This indicates that 2.8 is involved in a fast dynamic
equilibrium with a symmetrical species, which we propose to be the product of Ir–H–Ir bridge cleavage
2.9. The next step is slow, and the system comes to equilibrium only after four hours (K
eq
= [2.10]/[2.8]=
0.626; ΔG
o
383
= 360 cal/mol; k
1
= 1.4(1) x 10
-4
s
-1
; and k
-1
= 2.2(1) x 10
-4
s
-1
). The equilibrated mixture at
room temperature contains chemical shifts of pure 2.8 and 2.10 only.
The structure of 2.10 was established by NMR studies.
1
H spectrum contains two hydride peaks in
the ratio 1 : 2 at -6.64 (d,
2
J
PH
= 150.4) and -8.98 (br. s) ppm respectively. Seven aromatic peaks indicate
that 2.10 has two ligands and one of them is ortho-metalated. Two doublets of the four tert-butyl groups
indicate the presence of a symmetry plane in the molecule.
1
H –
31
P HMBC experiment demonstrates
coupling between different hydrides (–6.64, and –8.98 ppm) and different phosphorus nuclei (63.79, and
88.66 ppm respectively). Hence, the only reasonable molecular structure (2.10) must have all three
hydrides bound to one iridium center (Scheme 2.2).
43
Scheme 2.2. Reactions of complex 2.8.
Complex 2.8 reacts with 10 eq. of n-hexanal at room temperature. This initially produces a number
of unidentified iridium hydride complexes. After two days at 80
o
C the reaction reaches completion and
all the transient iridium hydrides turn to a single complex, 2.11 (Scheme 2.2). Its structure was determined
with NMR and MALDI-MS data. The
1
H NMR spectrum of 2.11 contains two peaks of the hydride ligands
at –8.44 (ddd) and –11.15 (ddd) ppm and six aromatic peaks, suggesting that both pyridine fragments are
ortho-metalated. No chemical exchange (EXSY) was observed between the hydride ligands, which is
consistent with their proposed trans-configuration. Complex 2.11 has two hydrogen atoms fewer than
2.8, meaning that it is a dehydrogenated form of 2.8. The identified organic products in this reaction are
1-hexanol and hexyl hexanoate. 1-Hexanol is the product of hydrogen transfer from 2.8 to n-hexanal, and
hexyl hexanoate is the product of Tishchenko-like dimerization of the aldehyde. Hexanal remains present
in the mixture after prolonged heating, showing that 2.11 does not catalyze its disproportionation; this is
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
H
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
H
N
Ir
Ir
CO
P
tBu
tBu H
N
H
H
P
N
Ir
P
Ir
CO
P
tBu
tBu
D
D
N
tBu
tBu
D
OD
D D
KOH, Toluene
2.8 2.10
2.8-d
4
D
2.9
CHO
C
6
H
6
, 25 - 80
o
C
2.11
C
6
H
13
OH
C
5
H
11
CO
2
C
6
H
13
2.8
reflux, 3h
2.8
+
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
H
2.12
t-BuOK, C
6
H
6
2.8
n-Hexanol
Ir Ir
P
H
P
H
CO N
N
tBu
tBu
tBu
tBu
44
most likely accessed via one of the transient iridium hydrides mentioned above. Reduction of 2.11 back
to 2.8 by 1-hexanol or H
2
(1 atm) at 110
o
C in toluene is not detected, even after 12 h.
When 2.2 reacts with 1-butanol and KOH in boiling toluene a mixture of iridium hydride complexes
is formed, in which 2.8, 2.10, and 2.11 are the major components (Figure 2.4). Moreover, 2.8 is active in
benzyl alcohol dehydrogenation with an identical kinetic profile to 2.2. These facts suggest that 2.8, 2.10,
and 2.11 are the catalyst resting states which convert among each other during alcohol dehydrogenation
with pre-catalyst 2.2.
Figure 2.4.
1
H NMR spectra (600 MHz, C
6
D
6
) demonstrating IrH peaks: (1) mixture of complexes formed in
the reaction between 2.2, 1-butanol, and KOH in boiling toluene; (2) 2.8; (3) 2.10; (4) 2.11.
Whereas the interconversion of 2.8 and 2.10 is accessed at elevated temperature, it is unclear how
2.8 can convert reversibly to 2.11 in the catalytic process. Nevertheless, this transformation is involved in
the catalytic mechanism according to a deuteration experiment. Treatment of 2.8 with 1-hexanol-O,1,1-
d
3
under dehydrogenation conditions (Scheme 2.2) reveals partial deuteration of all three hydrides and
the pyridine ortho-hydrogen in equal portions. Thus, all three hydrides are reversibly derivatized under
-22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4
f1 (ppm)
4
3
2
1
45
the catalytic conditions. Since 2.11 contains two ortho-metalated pyridine fragments, it is proposed as the
intermediate in the ortho-deuteration of the free pyridine fragment of 2.8.
The linking methylene group of complex 2.8 has an acidity comparable to that of alcohols
(Scheme 2.2), but the deprotonated form was not observed as a major species in catalysis. For example,
treating yellow solution of 2.8 with t-BuOK in benzene gives red-colored complex 2.12 (Scheme 2.2).
1
H
NMR spectrum of 2.12 shows selective deprotonation of benzylic arm of the metalated ligand and
dearomatization of the corresponding pyridine system. The hydride ligands remain intact. Similar
reactivity of structurally related PNP pincer ligands with similar colorimetric behavior was reported by
Milstein.
34
Complex 2.12 undergoes complete protonation by 1-hexanol to return initial 2.8, indicating
that 2.8 is more acidic than t-BuOH, but less acidic than 1-hexanol.
Scheme 2.3 illustrates the proposed mechanism of catalyst generation and catalytic alcohol
dehydrogenation using complex 2.2 as a pre-catalyst. It is likely that both 2.1 and 2.2 initiate through
analogous sequences, but the hydrides of 2.1 are high energy, and are thus not observed. The difference
in hydride stabilities is a consequence of the subtle electronic differences between the respective carbene
and phosphine groups of 2.1 and 2.2. The first step involves a nucleophilic attack of an alkoxide anion on
2.2, producing iridium(I) alkoxide, which is the structural analogue of 2.6. The alkoxide complex undergoes
β-hydride elimination to give an aldehyde and complex 2.7, the mechanism of this transformation had
been studied previously on a similar iridium complex.
26
Complex 2.7 is stable at room temperature, and subsequent intermediates were accessed at
elevated temperature. Complex 2.7 forms mixtures of iridium hydride species when reacted with 1-
butanol or n-hexanal at 80
o
C, however, complex 2.8 is detected after reaction with n-hexanal. Hence, it
was concluded that 2.7 can be converted to 2.8 by an aldehyde, thus giving an access to the 2.8/2.10
equilibrium. Since 2.8 reacts with n-hexanal rather than 1-hexanol, it is likely that the next step of the
mechanism involves reversible reaction between 2.9 and an aldehyde, ultimately leading to 2.11. One of
46
the intermediates in this reaction is the jumping-off point for the catalytic process (“Active Catalyst’’,
Scheme 2.3). The catalytic cycle operates by a traditional β-hydride elimination from an intermediate
iridium alkoxide. This process is irreversible, because toluene solutions of 2.8, 2.10, and 2.11 do not react
with H
2
(1 atm) at either 25 or 110
o
C. Although it was not possible to fully characterize the chain of all
iridium species involved, all of them are dinuclear, starting from 2.8.
Scheme 2.3. Mechanism of precatalyst 2.2 activation.
Studies on the organic intermediates involved in the alcohol dehydrogenation process turned up two
unexpected observations (Scheme 2.4). First, formation of ester by-products rules in the possibility of
Tishchenko-like reaction of an intermediate aldehyde. Second, kinetic evidence necessitates Cannizzaro
reaction in the mechanism of oxidation of benzyl alcohols.
Synthesis of 2.6 is illustrated in Scheme 2.1. Upon exposure to the catalytic conditions at 25
o
C, this
material generates 4,4’-dimethoxybenzyl benzoate, which indicates that Tishchenko-like reaction of 4-
methoxybenzaldehyde is faster than its direct conversion to 4-methoxybenzoate. Moreover, formation of
hexyl hexanoate in the reaction between 2.8 and n-hexanal shows that ester generation is also possible
Ir
O
R
2.7
2.2
Ir
P
H
N
tBu
tBu
Ir
P
N
tBu tBu
OTf
P
N
tBu tBu
RCH
2
O
RCHO
RCHO
RCH
2
OH
KOH
RCO
2
K
H
2
Catalytic
Cycle
Active
Catalyst
RCH
2
OH
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
H
N
Ir
P
Ir
CO
P
tBu
tBu
H
H
N
H
N
Ir
Ir
CO
P
tBu
tBu H
N
H
H
P
2.8 2.10 2.9
2.11
Ir Ir
P
H
P
H
CO N
N
tBu
tBu
tBu
tBu
47
when pre-catalyst 2.2 is used. In order to verify the proposed Tishchenko pathway, it was shown that a
significant portion of an aldehyde exists in the hemiacetal form under catalytic conditions: NMR data show
that n-hexanal reacts with an excess of 1-butanol in the presence of catalytic KOH in toluene to give the
corresponding hemiacetal (1-butoxyhexan-1-ol). Thus, the ester formation must be considered as a route
in the mechanism of carboxylate synthesis (Scheme 2.4A).
Scheme 2.4. Mechanisms of aldehyde and carboxylate formation.
Aromatic aldehydes undergo Cannizzaro reaction in the presence of KOH to give the corresponding
benzyl alcohols and carboxylates (Scheme 2.4B). Such disproportionation is known under the conditions
in the absence of iridium (1 h, KOH, toluene, 110
o
C).
18
Under catalytic conditions, the resulting alcohol
converts to aldehyde via iridium-catalyzed dehydrogenation. Moreover, the Cannizzaro reaction must be
happening, because when benzaldehyde is used instead of an alcohol under typical dehydrogenation
conditions, it takes ca. 30 min for hydrogen evolution to begin. If no Cannizzaro reaction was involved,
aldehyde oxidation would initiate immediately. This delay is due to benzaldehyde disproportionation that
generates a sufficient amount of benzyl alcohol which is required to form the catalytic species, an
aldehyde cannot fill this role. After hydrogen formation ceases, traces of benzyl alcohol can be detected
R
O
H
R O
OH
R R O
O
R
R O
O
Ar
O
H
Ar O
O
Ar OH
KOH
Cannizzaro Reaction
+
[ Ir ], - H
2
K
K
[ Ir ]
- H
2
KOH
R OH
R OH
R O
OH
[ Ir ]
- H
2
R OH
[ Ir ]
- H
2
Direct Oxidation
Tishchenko
Pathway
A.
Tishchenko pathway cannot be excluded as a mechanism for carboxylate formation.
B.
Oxidation of benzyl alcohols involves a Cannizzaro disproportionation.
KOH
48
in the reaction mixture by
1
H NMR spectroscopy. These observations necessitate Cannizzaro reaction, but
do not necessitate or exclude Tishchenko reaction in the sequence.
2.3. Conclusions
Complexes 2.1 and 2.2 are efficient pre-catalysts for the conversion of primary alcohols to potassium
carboxylates. Under optimized the reaction conditions the method applicable to a wide range of
substrates, including some (amino alcohols and some heterocycles) that are unknown for any catalytic
conditions in this class. Complexes 2.1 and 2.2 are both active in primary alcohol dehydrogenation, despite
their previously investigated difference in catalytic activity towards glycerol and formic acid
dehydrogenation. Upon catalysis initiation, complex 2.1 forms observable iridium(I) alkoxide 2.6, which
decomposes to relatively reactive iridium hydrides. On the contrary, complex 2.2 reacts with alcohols in
the presence of KOH to form a number of stable iridium hydride complexes 2.7, 2.8, 2.10, and 2.11 even
though iridium(I) alkoxide intermediate is not observed. The proposed jumping-off point for catalysis is
an intermediate in the equilibration of 2.8 and 2.11.
Taken together with prior work on glycerol and formic acid dehydrogenation, realized respectively
with 2.1 and 2.2, these data help to frame a picture that explains the specify of 2.1 and 2.2 for those
processes: both proceed through initiation sequences that are differentiated by the reactivities of
intermediate iridium hydride complexes that steer initiation to the respective active species. These
stabilities are apparently governed by differences in metal-ligand bonding between NHC carbene and
phosphine groups, thus illustrating dramatic consequences manifested by the subtle differences in these
ligating moieties.
49
2.4. Experimental Section
2.4.1. Materials and Methods
Chloroform-d
1
, dimethyl sulfoxide-d
6
, methanol-d
4
, D
2
O, benzene-d
6
, and toluene-d
8
were purchased
from Cambridge Isotopes Laboratories. Benzene-d
6
, toluene-d
8
, and toluene were dried and distilled
according to known procedures. Iridium complexes 2.1, 2.2, 2.3, and 2.4 were synthesized according to
described procedures.
20,21
Substrate alcohols, methanol, isopropanol, dichloromethane, ethyl acetate,
methyl hexanoate, chloro(1,5-cyclooctadiene)iridium(I) dimer, and potassium hydroxide were purchased
from commercial sources without further purification. Benzaldehyde was distilled under reduced pressure
prior to use. All air and water sensitive procedures were carried out in a Vacuum Atmosphere glove box
under nitrogen (2-10 ppm O
2
for all manipulations).
1
H,
13
C,
31
P NMR spectra were recorded on Varian
Mercury 400 and VNMRS 600 spectrometers, and processed using MestReNova v11.0.2. All chemical shifts
are reported in ppm and referenced to the residual
1
H or
13
C solvent peaks. Following abbreviations are
used: (s) singlet, (bs s) broad singlet, (d) doublet, (t) triplet, (dd) double doublet, etc. NMR spectra of air-
sensitive compounds were taken in 8” J. Young tubes (Wilmad or Norell) with Teflon valve plugs. Infrared
spectra were recorded on Bruker OPUS FTIR spectrometer. Samples of pure potassium carboxylates were
treated with acetic acid in ethyl acetate followed by GC-MS analysis on Thermo Scientific Focus DSQ II
instrument. MALDI-MS spectra were acquired on Bruker Autoflex Speed MALDI Mass Spectrometer.
Elemental analyses were conducted on Flash 2000 CHNS Elemental Analyzer.
2.4.2. General Procedure for Alcohol Dehydrogenation
An alcohol (2.0 mmol), iridium complex 2.1 or 2.2 (see Table 2.2), and potassium hydroxide (123 mg,
2.2 mmol) were mixed with dry toluene (10 mL). The suspension was stirred at reflux for required period
of time (oil bath, 120
o
C). After the reaction was over, the solvent was evaporated under reduced pressure
affording crude potassium carboxylate.
50
Isolation method A: Potassium carboxylate was dissolved in deionized water (40 mL) and the resulting
solution was washed with dichloromethane (2 x 10 mL). Then, the solution was acidified with 1 M HCl,
and extracted with ethyl acetate (3 x 10 mL). The organic phase was separated, dried (Na
2
SO
4
) and
evaporated in vacuum, giving pure carboxylic acid.
Isolation method B: Potassium carboxylate was dissolved in DI water (40 mL) and the resulting
solution was washed with dichloromethane (2 x 10 mL). The aqueous solution was evaporated in vacuum
to dryness and the residue was dissolved in methanol. The methanol solution was filtered, and the filtrate
was evaporated to dryness, giving pure potassium carboxylate.
51
Potassium butyrate (2a) was isolated by method B as a white powder (0.24 g, 96%).
1
H NMR (600 MHz, D
2
O): δ 2.16 (t, J = 7.3 Hz, 2H, CH
2
), 1.57 (h, J = 7.3 Hz, 2H, CH
2
), 0.90 (t, J = 7.4 Hz,
3H, CH
3
).
13
C{
1
H} NMR (151 MHz, D
2
O): δ 184.05, 39.64, 19.35, 13.26.
IR (PE film, cm
-1
): 2956, 2918, 1564, 1412, 1254, 888, 750.
GC-MS: m/z calcd. for C
4
H
8
O
2
[M]
+
88.05, found 88.1.
Figure 2.5.
1
H and
13
C{
1
H} NMR spectra of 2a in D
2
O.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0
f1 (ppm)
3.27
2.00
2.00
0.89
0.90
0.92
1.54
1.55
1.56
1.57
1.58
1.60
2.15
2.16
2.18
4.79 Water
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
13.26
19.35
39.64
184.05
COOK
52
Potassium octanoate (2b) was isolated by method B as a white powder (0.33 g, 90%).
1
H NMR (400 MHz, D
2
O): δ 2.18 (t, J = 7.5 Hz, 2H, CH
2
), 1.63 – 1.47 (m, 2H, CH
2
), 1.38 – 1.20 (m, 8H,
4CH
2
), 0.88 (t, J = 6.7 Hz, 3H, CH
3
).
13
C{
1
H} NMR (100 MHz, D
2
O): δ 184.13, 37.50, 30.88, 28.55, 28.09, 25.75, 21.83, 13.24.
IR (KBr, cm
-1
): 2954, 2926, 2854, 1563, 1411, 914, 718, 694.
GC-MS: m/z calcd. for C
8
H
16
O
2
[M]
+
144.12, found 144.1.
Figure 2.6.
1
H and
13
C{
1
H} NMR spectra of 2b in D
2
O.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0
f1 (ppm)
3.01
8.17
1.86
2.00
0.86
0.88
0.89
1.30
1.55
2.16
2.18
2.20
4.79 Water
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
13.24
21.83
25.75
28.09
28.55
30.88
37.50
184.13
COOK
53
Potassium palmitate (2c). After evaporation of toluene, crude 2c was washed with hexanes and dried
under reduced pressure. White powder (0.50 g, 85%).
1
H NMR (600 MHz, CD
3
OD): δ 2.15 (t, J = 8.6 Hz, 2H, CH
2
), 1.63 – 1.55 (m, 2H, CH
2
), 1.35 – 1.25 (m,
24H, 12CH
2
), 0.90 (t, J = 7.0 Hz, 3H, CH
3
).
13
C{
1
H} NMR (151 MHz, CD
3
OD): δ 183.12, 39.38, 33.07, 30.90, 30.79 (6CH
2
), 30.76, 30.68, 30.47,
27.85, 23.73, 14.45.
IR (PE film, cm
-1
): 2925, 2850, 1561, 1472, 1331, 1104, 716.
GC-MS: m/z calcd. for C
16
H
32
O
2
[M]
+
256.24, found 256.3.
Figure 2.7.
1
H and
13
C{
1
H} NMR spectra of 2c in CD
3
OD.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
3.15
25.97
2.14
2.00
0.89
0.90
0.91
1.28
1.31
1.58
1.59
1.61
2.13
2.15
2.16
3.31 Methanol
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
14.45
23.73
27.85
30.47
30.68
30.76
30.79
30.90
33.07
39.38
49.00 CD3OD
183.12
COOK
54
Potassium cyclobutanecarboxylate (2d) was isolated by method B as a white powder (0.22 g, 81%).
1
H NMR (600 MHz, D
2
O): δ 3.03 (p, J = 8.7 Hz, 1H, CH), 2.15 – 2.05 (m, 4H, 2CH
2
), 1.89 (h, J = 9.2 Hz,
1H, CH
2
), 1.78 – 1.70 (m, 1H, CH
2
).
13
C{
1
H} NMR (151 MHz, D
2
O): δ 185.74, 40.92, 25.93, 17.29.
IR (PE film, cm
-1
): 2975, 2941, 2859, 1656, 1553, 1409, 680.
GC-MS: m/z calcd. for C
5
H
8
O
2
[M]
+
100.05, found 100.1.
Figure 2.8.
1
H and
13
C{
1
H} NMR spectra of 2d in D
2
O.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0
f1 (ppm)
1.15
1.19
4.47
1.00
1.74
1.75
1.85
1.87
1.88
1.90
1.91
1.93
2.08
2.09
2.11
3.00
3.02
3.03
3.05
3.06
4.79 Water
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
17.29
25.93
40.92
185.74
COOK
55
1-Adamantanecarboxylic acid (2e). Isolation by method A followed by recrystallization from hexane-
ethanol mixture gave 2e as colorless crystals (0.34 g, 77%).
1
H NMR (600 MHz, CDCl
3
): δ 2.00 – 2.05 (m, 3H, 3CH), 1.88 – 1.94 (m, 6H, 3CH
2
), 1.67 – 1.77 (m, 6H,
3CH
2
).
13
C{
1
H} NMR (151 MHz, CDCl
3
): δ 184.45, 40.64, 38.71, 36.57, 27.97.
IR (PE film, cm
-1
): 2928, 1693, 1450, 1410, 1284, 1085, 951, 744, 670, 531.
GC-MS: m/z calcd. for C
11
H
16
O
2
[M]
+
180.12, found 180.1.
Figure 2.9.
1
H and
13
C{
1
H} NMR spectra of 2e in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
5.99
5.96
3.00
1.69
1.71
1.73
1.75
1.91
1.91
2.03
7.26 CHCl3
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
f1 (ppm)
27.97
36.57
38.71
40.64
77.16 CHCl3
184.45
COOH
56
Benzoic acid (2f). Isolation by method A followed by recrystallization from toluene gave 2f as
colorless crystals (0.24 g, 98%).
1
H NMR (600 MHz, DMSO-d
6
): δ 12.93 (br s, 1H, CO
2
H), 7.95 (d, J = 7.0 Hz, 2H, 2CH), 7.62 (t, J = 7.4
Hz, 1H, CH), 7.50 (t, J = 7.7 Hz, 2H, 2CH).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 167.33, 132.88, 130.76, 129.27, 128.58.
IR (PE film, cm
-1
): 1689, 1455, 1426, 1327, 1294, 936, 709.
GC-MS: m/z calcd. for C
7
H
6
O
2
[M]
+
122.04, found 122.0.
Figure 2.10.
1
H and
13
C{
1
H} NMR spectra of 2f in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0
f1 (ppm)
2.16
1.00
2.07
0.74
2.50 DMSO
7.49
7.50
7.51
7.61
7.62
7.63
7.94
7.95
12.93
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
128.58
129.27
130.76
132.88
167.33
COOH
57
4-Methoxybenzoic acid (2g). Isolation by method A followed by recrystallization from toluene-
ethanol mixture gave 2g as colorless crystals (0.24 g, 79%).
1
H NMR (600 MHz, DMSO-d
6
): δ 12.62 (br s, 1H, CO
2
H), 7.89 (d, J = 8.7 Hz, 2H, 2CH), 7.01 (d, J = 8.7
Hz, 2H, 2CH), 3.81 (s, 3H, CH
3
).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 167.04, 162.86, 131.37, 123.00, 113.83, 55.45.
IR (PE film, cm
-1
): 1683, 1603, 1427, 1301, 1263, 1168, 1026, 927, 844, 773, 617, 550.
GC-MS: m/z calcd. for C
8
H
8
O
3
[M]
+
152.05, found 152.0.
Figure 2.11.
1
H and
13
C{
1
H} NMR spectra of 2g in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0
f1 (ppm)
3.33
2.07
2.00
0.83
2.50 DMSO
3.81
7.00
7.02
7.88
7.90
12.62
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
55.45
113.83
123.00
131.37
162.86
167.04
COOH H
3
CO
58
4-(Methylthio)benzoic acid (2h). Isolation by method A followed by recrystallization from toluene-
ethanol mixture gave 2h as colorless crystals (0.25 g, 74%).
1
H NMR (500 MHz, CD
3
OD): δ 7.92 (d, J = 7.9 Hz, 2H, 2CH), 7.30 (d, J = 8.1 Hz, 2H, 2CH), 2.52 (s, 3H,
CH
3
).
13
C{
1
H} NMR (126 MHz, CD
3
OD): δ 169.62, 147.25, 131.07, 127.81, 125.94, 14.66.
IR (KBr, cm
-1
): 1680, 1595, 1421, 1325, 1192, 757.
GC-MS: m/z calcd. for C
8
H
8
O
2
S [M]
+
168.02, found 168.0.
Figure 2.12.
1
H and
13
C{
1
H} NMR spectra of 2h in CD
3
OD.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
3.00
2.00
2.01
2.52
3.31 Methanol
7.29
7.31
7.91
7.92
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
14.66
49.00 Methanol
125.94
127.81
131.07
147.25
169.62
COOH H
3
CS
59
4-Chlorobenzoic acid (2i). Isolation by method A followed by recrystallization from toluene-ethanol
mixture gave 2i as colorless crystals (0.25 g, 80%).
1
H NMR (400 MHz, DMSO-d
6
): δ 13.09 (br s, 1H, CO
2
H), 7.93 (d, J = 8.5 Hz, 2H, 2CH), 7.55 (d, J = 8.5
Hz, 2H, 2CH).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 166.49, 137.83, 131.16, 129.67, 128.75.
IR (KBr, cm
-1
): 2924, 2955, 1680, 1322, 1284, 762.
GC-MS: m/z calcd. for C
7
H
5
ClO
2
[M]
+
156.00, 157.99; found 156.0, 158.0.
Figure 2.13.
1
H and
13
C{
1
H} NMR spectra of 2i in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0
f1 (ppm)
2.03
2.00
0.53
2.50 DMSO
7.54
7.56
7.92
7.94
13.09
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
128.75
129.67
131.16
137.83
166.49
COOH Cl
60
4-Bromobenzoic acid (2j). Isolation by method A followed by recrystallization from toluene-ethanol
mixture gave 2j as colorless crystals (0.16 g, 40%).
1
H NMR (600 MHz, DMSO-d
6
): δ 13.17 (s, 1H, CO
2
H), 7.86 (d, J = 7.1 Hz, 2H, 2CH), 7.70 (d, J = 7.1 Hz,
2H, 2CH).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 166.58, 131.68, 131.27, 130.00, 126.85.
IR (PE film, cm
-1
): 1676, 1587, 1426, 1320, 1070, 1013, 758.
GC-MS: m/z calcd. for C
7
H
5
BrO
2
[M]
+
199.95, 201.95; found 199.9, 201.9.
Figure 2.14.
1
H and
13
C{
1
H} NMR spectra of 2j in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0
f1 (ppm)
4.10
1.00
2.50 DMSO
7.70
7.71
7.85
7.86
13.17
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
126.85
130.00
131.27
131.68
166.58
COOH Br
61
4-Iodobenzoic acid (2k). Isolation by method A followed by recrystallization from toluene-ethanol
mixture gave 2k as colorless crystals (0.21 g, 42%).
1
H NMR (600 MHz, DMSO-d
6
): δ 13.12 (s, 1H, CO
2
H), 7.88 (d, J = 8.1 Hz, 2H, 2CH), 7.69 (d, J = 8.0 Hz,
2H, 2CH).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 166.88, 137.55, 131.04, 130.27, 101.14.
IR (PE film, cm
-1
): 1675, 1427, 1009, 754.
MALDI-MS: m/z calcd. for C
7
H
5
INaO
2
[M + Na]
+
270.92, found 270.72.
Figure 2.15.
1
H and
13
C{
1
H} NMR spectra of 2k in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0
f1 (ppm)
2.03
2.00
0.97
2.50 DMSO
7.68
7.69
7.88
7.89
13.12
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
39.66
101.14
130.27
131.04
137.55
166.88
COOH I
62
1-Naphthoic acid (2l). Isolation by method A followed by recrystallization from toluene gave 2l as
colorless crystals (0.29 g, 84%).
1
H NMR (600 MHz, DMSO-d
6
): δ 13.14 (s, 1H, CO
2
H), 8.87 (d, J = 8.6 Hz, 1H, CH), 8.15 (d, J = 7.4 Hz,
2H, 2CH), 8.01 (d, J = 8.0 Hz, 1H, CH), 7.64 (t, J = 7.7 Hz, 1H, CH), 7.59 (t, J = 7.7 Hz, 2H, 2CH).
13
C{
1
H} NMR (151 MHz, DMSO-d
6
): δ 168.65, 133.46, 132.92, 130.67, 129.84, 128.59, 127.71, 127.55,
126.17, 125.48, 124.87.
IR (PE film, cm
-1
): 2916, 1674, 1593, 1306, 774.
MALDI-MS: m/z calcd. for C
11
H
8
NaO
2
[M + Na]
+
195.04, found 194.87.
Figure 2.16.
1
H and
13
C{
1
H} NMR spectra of 2l in DMSO-d
6
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0
f1 (ppm)
3.19
1.09
2.07
1.00
1.03
2.50 DMSO
7.57
7.59
7.60
7.63
7.64
7.66
8.00
8.02
8.15
8.16
8.86
8.88
13.14
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
39.52 DMSO
124.87
125.48
126.17
127.55
127.71
128.59
129.84
130.67
132.92
133.46
168.65
COOH
63
Potassium ethylaminoacetate (2m) isolated by method B as a white powder (0.23 g, 82%).
1
H NMR (600 MHz, D
2
O): δ 3.26 (s, 2H, CH
2
), 2.70 (q, J = 6.8 Hz, 2H, CH
2
), 1.13 (t, J = 7.1 Hz, 3H, CH
3
).
13
C{
1
H} NMR (151 MHz, D
2
O): δ 177.81, 51.11, 42.62, 12.90.
IR (PE film, cm
-1
): 1597, 1407, 1383, 1283.
MALDI-MS: m/z calcd. for C
4
H
8
K
2
NO
2
[M + K]
+
179.98, found 180.00.
Figure 2.17.
1
H and
13
C{
1
H} NMR spectra of 2m in D
2
O.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0
f1 (ppm)
3.13
1.97
2.00
1.12
1.13
1.14
2.69
2.70
2.71
2.72
3.26
4.79 Water
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
12.90
42.62
51.11
177.81
N
H
COOK
64
Indole (2n). Complex 2.2 (2.7 mg, 4 µmol), 2-(2-aminophenyl)ethanol (274 mg, 2.0 mmol), and
potassium hydroxide (123 mg, 2.2 mmol) were mixed with dry toluene (10 mL). The suspension was stirred
at reflux for 13 hours (oil bath, 120
o
C). After the reaction was over, the solvent was evaporated in vacuum,
and the residue was stirred at reflux with hexanes (50 mL) and charcoal for 1 h. Then, the hexane solution
was filtered and evaporated in vacuum giving 2n as a colorless liquid (0.19 g, 80%).
1
H NMR (600 MHz, CDCl
3
): δ 8.11 (br s, 1H, NH), 7.68 (dd, J = 7.8, 0.7 Hz, 1H, CH), 7.41 (dd, J = 8.0,
0.7 Hz, 1H, CH), 7.25 – 7.19 (m, 2H, 2CH), 7.17 – 7.12 (m, 1H, CH), 6.60 – 6.56 (m, 1H, CH).
13
C{
1
H} NMR (151 MHz, CDCl
3
): δ 135.88, 127.95, 124.25, 122.09, 120.84, 119.92, 111.14, 102.71.
IR (PE film, cm
-1
): 3401, 1457, 1353, 1246, 1090, 932, 746, 612, 505, 430.
GC-MS: m/z calcd. for C
8
H
7
N [M]
+
117.06, found 117.1.
Figure 2.18.
1
H and
13
C{
1
H} NMR spectra of 2n in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
0.85
1.05
2.03
1.01
1.00
0.85
6.58
7.14
7.15
7.16
7.21
7.22
7.24
7.26 CHCl3
7.40
7.40
7.41
7.41
7.67
7.67
7.68
7.69
8.11
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
77.16 CHCl3
102.71
111.14
119.92
120.84
122.09
124.25
127.95
135.88
N
H
65
3-Phenylpropanoic acid (2o). Isolation by method A gave 2o as a yellow liquid (0.24 g, 80%).
1
H NMR (600 MHz, CDCl
3
): δ 11.57 (br s, 1H, CO
2
H), 7.34 – 7.29 (m, 2H, 2CH), 7.25 – 7.20 (m, 3H,
3CH), 2.99 (t, J = 7.8 Hz, 2H, CH
2
), 2.71 (t, J = 7.8 Hz, 2H, CH
2
).
13
C{
1
H} NMR (151 MHz, CDCl
3
): δ 179.51, 140.28, 128.70, 128.40, 126.52, 35.76, 30.70.
IR (PE film, cm
-1
): 3028, 1708, 1496, 1417, 1295, 1215, 936, 748, 699.
GC-MS: m/z calcd. for C
9
H
10
O
2
[M]
+
150.07, found 150.1.
Figure 2.19.
1
H and
13
C{
1
H} NMR spectra of 2o in CDCl
3
.
-2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
f1 (ppm)
2.03
2.00
2.91
1.78
0.74
2.70
2.71
2.73
2.97
2.99
3.00
7.23
7.25
7.26 CHCl3
7.31
7.33
11.57
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
30.70
35.76
77.16 CDCl3
126.52
128.40
128.70
140.28
179.51
COOH
66
Potassium pyridine-2-carboxylate (2p) was isolated by method B as a white powder (0.20 g, 63%).
1
H NMR (500 MHz, CD
3
OD): δ 8.58 (d, J = 4.4 Hz, 1H, CH), 8.02 (d, J = 7.7 Hz, 1H, CH), 7.85 (t, J = 8.1
Hz, 1H, CH), 7.46 – 7.32 (m, 1H, CH).
13
C{
1
H} NMR (126 MHz, CD
3
OD): δ 172.94, 156.47, 149.55, 138.17, 125.93, 125.01.
IR (KBr, cm
-1
): 2927, 1640, 1405, 702.
GC-MS: m/z calcd. for C
6
H
5
NO
2
[M]
+
123.03, found 123.0.
Figure 2.20.
1
H and
13
C{
1
H} NMR spectra of 2p in CD
3
OD.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
0.97
0.99
0.96
1.00
3.32 Methanol
7.40
7.41
7.41
7.41
7.42
7.83
7.85
7.86
8.01
8.03
8.57
8.58
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
f1 (ppm)
49.00 Methanol
125.01
125.93
138.17
149.55
156.47
172.94
N COOK
67
Potassium quinoline-2-carboxylate (2q) was isolated by method B as a white powder (0.27 g, 65%).
1
H NMR (600 MHz, D
2
O): δ 7.88 (d, J = 8.5 Hz, 1H, CH), 7.77 (d, J = 8.5 Hz, 1H, CH), 7.60 (d, J = 8.4
Hz, 1H, CH), 7.50 (t, J = 7.7 Hz, 1H, CH), 7.45 (d, J = 8.1 Hz, 1H, CH), 7.28 (t, J = 7.5 Hz, 1H, CH).
13
C{
1
H} NMR (151 MHz, D
2
O): δ 172.84, 154.01, 145.89, 137.75, 130.12, 128.09, 127.96, 127.60,
127.38, 120.13.
IR (KBr, cm
-1
): 3298, 1615, 1387, 802, 770.
GC-MS: m/z calcd. for C
9
H
7
N [M – CO
2
]
+
129.16, found 129.1.
Figure 2.21.
1
H and
13
C{
1
H} NMR spectra of 2q in D
2
O.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0
f1 (ppm)
0.99
1.00
1.00
0.97
0.97
1.00
4.79 Water
7.27
7.28
7.29
7.44
7.45
7.49
7.50
7.51
7.59
7.61
7.76
7.77
7.87
7.88
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
120.13
127.38
127.60
127.96
128.09
130.12
137.75
145.89
154.01
172.84
N COOK
68
2.4.3. Synthesis of Iridium Complexes
[Ir(2-PyCH
2
(C
4
H
5
N
2
))(η
2
-COD)(OCH
2
C
6
H
4
OMe)] (2.6). In a glovebox, complex 2.1 (40.0 mg, 6.4 x 10
-5

mol), 4-methoxybenzyl alcohol (18.0 mg, 1.3 x 10
-4
mol), potassium hydroxide (7.2 mg, 1.3 x 10
-4
mol) and
2 – 3 drops of C
6
D
6
were mixed together till the slurry turned yellow. Then, C
6
D
6
(0.7 mL) was added
resulting in a yellow solution of 2.6 and potassium triflate precipitate. The solution was immediately
filtered and transferred to J. Young NMR tube. The structure of 2.6 was derived from NMR data.
1
H NMR (600 MHz, C
6
D
6
): δ 8.33 (dq, J = 5.0, 0.9 Hz, 1H, Py), 7.39 (d, J = 7.8 Hz, 1H, Py), 7.35 (d, J =
8.6 Hz, 2H, C
6
H
4
), 7.08 (td, J = 7.7, 1.8 Hz, 1H, Py), 6.85 (d, J = 8.6 Hz, 2H, C
6
H
4
), 6.64 (d, J = 1.9 Hz, 1H, NHC),
6.58 (ddd, J = 7.5, 4.8, 1.1 Hz, 1H, Py), 5.86 (d, J = 1.9 Hz, 1H, NHC), 5.73 (d, J = 14.7 Hz, 1H, NCH
2
), 5.42 (d,
J = 14.7 Hz, 1H, NCH
2
), 5.24 (d, J = 13.8 Hz, 1H, OCH
2
), 5.10 (td, J = 7.7, 3.6 Hz, 1H, =CH), 5.00 – 5.06 (m,
1H, =CH), 4.85 (d, J = 13.7 Hz, 1H, OCH
2
), 3.40 (s, 3H, OCH
3
), 3.19 (s, 3H, NCH
3
), 2.49 (td, J = 7.0, 2.4 Hz, 1H,
=CH), 2.41 (td, J = 7.4, 3.0 Hz, 1H, =CH), 2.28 – 2.37 (m, 3H, 2CH
2
), 2.11 – 2.17 (m, 1H, CH
2
), 1.62 – 1.83 (m,
4H, 2CH
2
).
13
C{
1
H} NMR (151 MHz, C
6
D
6
, derived from HSQC and HMBC): δ 183.25, 158.69, 156.75, 149.34,
141.45, 136.46, 127.26, 123.17, 122.46, 120.82, 120.56, 113.36, 84.78, 84.04, 75.30, 55.27, 54.66, 45.81,
45.44, 36.38, 34.54, 33.77, 29.90, 29.23.
MALDI-MS: m/z calcd. for C
26
H
32
IrN
3
O
2
[M]
+
611.21, found 611.14.
Figure 2.22.
1
H NMR spectrum of 2.6 in C
6
D
6
(relevant peaks are integrated).
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5
f1 (ppm)
4.86
1.18
3.24
1.14
1.09
2.88
3.15
1.07
1.08
1.09
1.18
1.00
1.03
0.94
1.25
0.95
1.97
1.00
1.88
0.99
0.87
1.65
1.73
1.79
2.14
2.33
2.41
2.49
3.19
3.40
4.84
4.86
5.03
5.10
5.23
5.25
5.41
5.43
5.71
5.74
5.86
5.87
6.57
6.59
6.64
6.65
6.84
6.86
7.06
7.08
7.09
7.16 Benzene
7.34
7.36
7.38
7.40
8.32
8.33
Ir
N
N
O
N
OMe
2.6
69
Figure 2.23. HSQC (top) and HMBC (bottom) NMR spectra of 2.6 in C
6
D
6
.
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5
f2 (ppm)
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
f1 (ppm)
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5
f2 (ppm)
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
f1 (ppm)
Ir
N
N
O
N
OMe
2.6
70
Figure 2.24.
1
H EXSY NMR spectrum of 2.6 in C
6
D
6
(excitation at 4.85 ppm).
Figure 2.25.
1
H NOESY NMR spectrum of 2.6 in C
6
D
6
.
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
-1.71
-1.00
-0.17
1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6
f1 (ppm)
0.08
1.00
-0.02
0.05
2.38
2.45
3.15
5.07
4-methoxybenzyl alcohol
Ir
N
N
O
N
OMe
2.6
NCH
3
–CH= (COD)
–CH
2
– (COD)
71
[IrH(η
1
,η
3
-C
8
H
12
)(2-PyCH
2
PBu
2
t
)] (2.7). In a glovebox, complex 2.2 (50.0 mg, 7.3 x 10
-5
mol), isopropyl
alcohol (20.0 mg, 3.3 x 10
-4
mol), and potassium hydroxide (12.0 mg, 2.2 x 10
-4
mol) were mixed with dry
benzene (1.0 mL) and stirred at room temperature for two days. Then, the brown solution was filtered,
and the solvent was evaporated in vacuum to dryness. The residue was recrystallized twice from benzene
affording the product as a pale-yellow crystalline powder (25.0 mg, 64%). Crystals suitable for X-ray
analysis were obtained by slow evaporation of benzene solution.
1
H NMR (600 MHz, C
6
D
6
): δ 7.77 (d, J = 5.6 Hz, 1H, Py), 6.65 (t, J = 7.3 Hz, 1H, Py), 6.44 (d, J = 7.5 Hz,
1H, Py), 6.05 (t, J = 6.4 Hz, 1H, Py), 5.20 – 5.13 (m, 1H, CH), 4.64 – 4.57 (m, 1H, CH), 3.91 (t, J = 7.8 Hz, 1H,
CH), 2.96 – 2.90 (m, 1H, CH), 2.87 (dd, J = 16.6, 9.0 Hz, 1H, PCH
2
), 2.68 (dd, J = 16.6, 8.2 Hz, 1H, PCH
2
), 2.62
– 2.51 (m, 1H, CH
2
), 2.27 – 2.11 (m, 4H, 3CH
2
), 2.05 – 1.99 (m, 1H, CH
2
), 1.94 – 1.77 (m, 2H, 2CH
2
), 1.38 (d,
J = 12.1 Hz, 9H, 3CH
3
), 1.10 (d, J = 12.3 Hz, 9H, 3CH
3
), –9.99 (d, J = 17.6 Hz, 1H, IrH).
13
C{
1
H} NMR (151 MHz, C
6
D
6
): δ 163.78, 148.87, 133.73, 121.87, 121.10, 96.21, 76.00, 60.79, 56.43,
55.14, 38.75, 36.48, 35.29, 30.34, 29.06, 28.05, 25.33, 14.01.
31
P{
1
H} NMR (243 MHz, C
6
D
6
): δ 56.20.
IR (KBr, cm
-1
): 2915, 2871, 2800, 2043, 1472, 821, 762.
MALDI-MS: m/z calcd. for C
22
H
37
IrNP [M]
+
539.23, found 539.31.
Anal. calcd for C
22
H
37
IrNP: C 49.05, H 6.92, N 2.60. Found: C 48.11, H 6.96, N 2.76.
Figure 2.26.
1
H NMR spectrum of 2.7 in C
6
D
6
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
9.95
9.63
2.18
1.07
4.14
1.04
1.09
1.99
1.03
1.00
1.00
0.91
0.99
0.77
1.00
1.09
1.11
1.37
1.39
1.82
1.85
1.87
1.90
2.01
2.04
2.13
2.14
2.18
2.22
2.26
2.57
2.59
2.65
2.67
2.68
2.69
2.84
2.85
2.87
2.88
2.92
2.93
2.93
2.94
3.90
3.91
3.92
4.59
4.61
4.63
5.15
5.17
6.02
6.04
6.05
6.42
6.43
6.62
6.64
6.65
7.16 Benzene
7.77
7.77
-10.1 -10.0 -9.9 -9.8
f1 (ppm)
1.00
-10.00
-9.97
Ir
P
H
N
2.7
72
Figure 2.27.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 2.7 in C
6
D
6
.
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.01
25.33
28.05
29.06
30.34
35.29
36.48
38.75
55.14
56.43
60.79
76.00
96.21
121.10
121.87
128.06 Benzene
133.73
148.87
163.78
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
56.20
Ir
P
H
N
2.7
73
Figure 2.28. COSY (top) and HSQC (bottom) NMR spectra of 2.7 in C
6
D
6
.
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0
f2 (ppm)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
f1 (ppm)
Ir
P
H
N
2.7
74
[Ir
2
H
3
(CO)(2-PyCH
2
PBu
2
t
){µ-(C
5
H
3
N)CH
2
PBu
2
t
}] (2.8). In a glovebox, complex 2.2 (50.0 mg, 7.3 x 10
-5

mol), n-butanol (108.0 mg, 1.46 x 10
-3
mol, 20 eq.), and potassium hydroxide (88.0 mg, 1.57 x 10
-3
mol,
21.5 eq.) were mixed with dry toluene (5 mL) in a 20 mL Straus flask. The flask was charged with a stirring
bar and sealed with a septum. Outside the glovebox, the flask was placed in an oil bath (120
o
C), and the
septum was immediately pierced with a syringe needle attached to eudiometer. In 15 min hydrogen
evolution stopped, and the solution color turned from dark-violet to orange. The flask was brought back
to the glovebox, and the precipitate (potassium butyrate) was filtered off and washed with toluene. The
orange solution was evaporated to dryness under vacuum, and then hexane (3 mL) was added to the solid
to form a yellow precipitate. The precipitate was filtered and washed with hexane. After crystallization
from benzene-hexane mixture, 2.8 was obtained as a yellow crystalline powder (20 mg, 63%). Crystals
suitable for X-ray analysis were obtained by slow addition of hexane to benzene solution.
1
H NMR (600 MHz, C
6
D
6
): δ 8.58 (d, J = 5.6 Hz, 1H, ArH), 7.90 (dd, J = 7.7, 2.1 Hz, 1H, ArH), 6.86 (t, J =
7.6 Hz, 1H, ArH), 6.78 (td, J = 7.5, 1.3 Hz, 1H, ArH), 6.62 (d, J = 7.8 Hz, 1H, ArH), 6.51 (d, J = 7.4 Hz, 1H, ArH),
6.07 (t, J = 7.1 Hz, 1H, ArH), 3.19 (dd, J = 15.7, 7.7 Hz, 1H, CH
2
), 3.00 (dd, J = 15.8, 7.3 Hz, 1H, CH
2
), 2.58 –
2.43 (m, 2H, CH
2
), 1.50 (d, J = 12.2 Hz, 9H, 3CH
3
), 1.37 (d, J = 12.1 Hz, 9H, 3CH
3
), 1.18 (d, J = 13.6 Hz, 9H,
3CH
3
), 1.11 (d, J = 13.4 Hz, 9H, 3CH
3
), –7.51 (dd, J = 67.6, 7.5 Hz, 1H, IrH), –13.87 (ddd, J = 26.7, 13.7, 5.3
Hz, 1H, IrH), –19.99 (dt, J = 12.2, 4.1 Hz, 1H, IrH).
13
C{
1
H} NMR (151 MHz, C
6
D
6
): δ 187.12 (d, J = 8.0 Hz), 178.55 (dd, J = 103.5, 4.4 Hz), 166.04 (d, J = 6.2
Hz), 164.98 (dd, J = 10.8, 6.1 Hz), 153.04 (d, J = 2.5 Hz), 144.85 (d, J = 7.7 Hz), 134.48, 133.03 (d, J = 4.6 Hz),
121.93 (d, J = 7.3 Hz), 120.35, 112.56 (d, J = 9.2 Hz), 39.69 (d, J = 16.1 Hz), 35.21 (d, J = 15.4 Hz), 35.06 (d,
J = 13.5 Hz), 34.71 (d, J = 12.0 Hz), 33.14 (d, J = 19.0 Hz), 30.92 (d, J = 23.9 Hz), 30.59 – 30.08 (m), 29.87 (d,
J = 4.6 Hz), 29.61 – 28.98 (m).
31
P{
1
H} NMR (243 MHz, C
6
D
6
): δ 89.01, 62.75. IR (KBr, cm
-1
): 2942, 2896,
2106, 1914, 1582, 1473, 826. MALDI-MS: m/z calcd. for C
29
H
50
Ir
2
N
2
OP
2
[M]
+
888.26, found 888.23. Anal.
calcd for C
29
H
50
Ir
2
N
2
OP
2
: C 39.18, H 5.67, N 3.15. Found: C 39.91, H 5.71, N 3.19.
75
Figure 2.29.
1
H NMR spectra of 2.8 in C
6
D
6
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5
f1 (ppm)
19.79
9.99
9.60
2.11
1.07
1.07
0.99
1.01
1.05
1.00
1.03
1.00
1.00
1.10
1.12
1.17
1.19
1.36
1.38
1.49
1.51
2.45
2.48
2.49
2.52
2.53
2.56
2.98
2.99
3.01
3.02
3.17
3.18
3.20
3.21
6.06
6.07
6.08
6.51
6.52
6.63
6.64
6.77
6.78
6.79
6.79
6.80
6.80
6.85
6.86
6.87
7.88
7.89
7.89
7.90
8.57
8.58
-21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5
f1 (ppm)
1.01
1.00
1.00
-20.02
-20.01
-20.01
-20.00
-19.99
-19.98
-13.92
-13.91
-13.89
-13.88
-13.87
-13.86
-13.85
-13.84
-7.58
-7.57
-7.47
-7.46
2.8
Ir Ir
N
P
H
H
Bu
t
Bu
t
CO
N
H
P
Bu
t
Bu
t
76
Figure 2.30.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 2.8 in C
6
D
6
.
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
f1 (ppm)
29.34
29.38
29.85
29.89
30.31
30.33
30.85
31.00
33.08
33.21
34.67
34.75
35.01
35.10
35.16
35.26
39.63
39.74
112.53
112.59
120.35
121.91
121.96
127.90
133.02
133.05
134.48
144.82
144.88
153.03
153.04
164.93
164.97
165.00
165.04
166.02
166.06
178.19
178.22
178.88
178.91
187.10
187.15
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
62.77
88.98
2.8
Ir Ir
N
P
H
H
Bu
t
Bu
t
CO
N
H
P
Bu
t
Bu
t
77
Figure 2.31. COSY NMR spectrum of 2.8 in C
6
D
6
.
-23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6
f2 (ppm)
-23
-22
-21
-20
-19
-18
-17
-16
-15
-14
-13
-12
-11
-10
-9
-8
-7
-6
-5
f1 (ppm)
2.8
Ir Ir
N
P
H
H
Bu
t
Bu
t
CO
N
H
P
Bu
t
Bu
t
78
2.4.4. Decomposition of 2.6
Complex 2.6 is unstable in a solution, and it completely decomposes in two days to 4,4’-
dimethoxybenzyl benzoate, cyclooctene, and iridium-containing precipitate.
4,4’-Dimethoxybenzyl benzoate:
1
H NMR (600 MHz, C
6
D
6
): δ 8.16 (d, J = 9.0 Hz, 2H, 2CH), 7.21 (d, J =
8.8 Hz, 2H, 2CH), 6.73 (d, J = 8.7 Hz, 2H, 2CH), 6.62 (d, J = 9.0 Hz, 2H, 2CH), 5.23 (s, 2H, CH
2
), 3.26 (s, 3H,
CH
3
), 3.13 (s, 3H, CH
3
). GC-MS: m/z calcd. for C
16
H
16
O
4
[M]
+
272.10, found 272.1.
Cyclooctene:
1
H NMR (600 MHz, C
6
D
6
): δ 5.62 – 6.67 (m, 2H, 2CH), 2.02 – 2.12 (m, 4H, 2CH
2
), 1.36 –
1.48 (m, 8H, 4CH
2
). GC-MS: m/z calcd. for C
8
H
14
[M]
+
110.11, found 110.1.

Figure 2.32.
1
H NMR spectrum of 2.6 decomposition products in C
6
D
6
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
13.48
6.87
3.08
2.99
1.90
2.57
2.00
1.93
1.78
1.66
1.41
1.45
1.46
2.05
2.07
2.08
3.13
3.26
5.23
5.64
5.65
5.65
6.61
6.63
6.72
6.74
7.16 Benzene
7.21
7.22
8.15
8.17
C
6
D
6
, RT, 2 days
Ir
N
N
O
N
OMe
2.6
O
O
MeO OMe
+
OMe
HO
[ Ir ] +
79
Figure 2.33. COSY (top) and HMBC (bottom) NMR spectra of 2.6 decomposition products in C
6
D
6
.
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0
f2 (ppm)
1
2
3
4
5
6
7
8
9
f1 (ppm)
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0
f2 (ppm)
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
f1 (ppm)
80
2.4.5. Isomerization of 2.8 to 2.10
A solution of 2.8 (40 mg) in toluene-d
8
(0.7 mL) was placed in a J. Young NMR tube and heated in an
oil bath at 110
o
C for 4 h. The resulting solution contained 2.8 and 2.10 in a 1.6 : 1 ratio (K
eq
= 0.626). The
structure of 2.10 was derived from the following NMR data.
1
H NMR (600 MHz, toluene-d
8
): δ 9.41 (d, J = 6.7 Hz, 1H, ArH), 7.26 (d, J = 8.0 Hz, 1H, ArH), 6.74 (td, J
= 7.7, 1.6 Hz, 1H, ArH), 6.61 (d, J = 7.8 Hz, 1H, ArH), 6.55 (t, J = 7.3 Hz, 1H, ArH), 6.20 (d, J = 7.3 Hz, 1H,
ArH), 5.98 (t, J = 7.2 Hz, 1H, ArH), 3.02 (d, J = 7.8 Hz, 2H, CH
2
), 2.52 (d, J = 8.7 Hz, 2H, CH
2
), 1.30 (d, J = 12.2
Hz, 18H, 6CH
3
), 1.23 (d, J = 13.4 Hz, 18H, 6CH
3
), –6.64 (d, J = 150.4 Hz, 1H, IrH), –8.98 (br s, 2H, 2IrH,
resolves to a doublet at 100
o
C with J = 46.2 Hz).
13
C{
1
H} NMR (151 MHz, toluene-d
8
, derived from HSQC and HMBC): δ 164.19, 163.48, 162.13, 159.87,
140.85, 134.09, 131.10, 121.13, 120.70, 109.83, 39.65, 34.44, 34.03, 31.80.
31
P{
1
H} NMR (243 MHz, toluene-d
8
): δ 88.66, 63.79.
Figure 2.34.
1
H NMR spectrum of 2.10 in C
6
D
6
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
29.49
25.28
1.98
1.91
1.22
1.20
0.80
2.32
1.05
1.00
1.24
1.27
1.34
1.37
2.52
2.54
3.02
3.04
5.97
6.22
6.23
6.51
6.53
6.64
7.16 Benzene
7.41
7.44
9.55
-10 -9 -8 -7 -6 -5
f1 (ppm)
2.03
1.05
-8.84
-6.59
-6.22
81
Figure 2.35.
31
P{
1
H} NMR spectrum of 2.10 in C
6
D
6
.
Figure 2.36. Time-course study of 2.8 isomerization by
1
H NMR (toluene-d
8
, 25
o
C).
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
63.78
88.78
-23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1
f1 (ppm)
0 h
0.5 h
1.17 h
3.0 h
2.10
2.8
82
The integrated rate law for the first order reversible reaction is given by equation:
ln
[𝐴 ] ― [𝐴 ]
∞
[𝐴 ]
0
― [𝐴 ]
∞
= ― (𝑘 1
+ 𝑘 ―1
)𝑡 Where [A] – current concentration of the reagent, [𝐴]
∞
– concentration at equilibrium, [A]
0
– initial
concentration, k
1
– rate constant of the forward reaction, and k
-1
– rate constant of the backward reaction.
Combination with equilibrium constant expression (𝐾 𝑒𝑞 = 𝑘 1
/𝑘 ―1
) followed by rearrangement gives:
(
𝐾 𝑒𝑞 𝐾 𝑒𝑞 + 1
)
ln
[𝐴 ] ― [𝐴 ]
∞
[𝐴 ]
0
― [𝐴 ]
∞
= ― 𝑘 1
𝑡 and (
1
𝐾 𝑒𝑞 + 1
)ln
[𝐴 ] ― [𝐴 ]
∞
[𝐴 ]
0
― [𝐴 ]
∞
= ― 𝑘 ―1
𝑡 k
1
and k
-1
can be found by plotting the left sides of the equations against time (Figure 2.37).

Figure 2.37. Kinetic profile of 2.8 isomerization.
K
eq
= 0.626
2.10
2.8
k
1
= 0.50 ± 0.02 h
-1
k
-1
= 0.79 ± 0.03 h
-1
83
Figure 2.38. HSQC (top) and
1
H–
13
C HMBC (bottom) NMR spectra of the equilibrium mixture of 2.8 and
2.10 (toluene-d
8
, 25
o
C).
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5
f2 (ppm)
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
f1 (ppm)
{2.08,20.43}Toluene
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f2 (ppm)
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
f1 (ppm)
{2.08,128.87}Toluene
84
Figure 2.39.
1
H–
31
P HMBC NMR spectra of the equilibrium mixture of 2.8 and 2.10 (toluene-d
8
, 25 and
100
o
C).
25
o
C
100
o
C
85
2.4.6. Deuteration of 2.8
In a glovebox, complex 2.8 (10.0 mg, 1.13 x 10
-5
mol), 1-hexanol-O,1,1-d
3
(59.0 mg, 5.62 x 10
-4
mol,
50 eq.), and potassium hydroxide (31.0 mg, 5.62 x 10
-4
mol, 50 eq.) were mixed with dry toluene (5 mL) in
a 20 mL Straus flask. The following manipulations were the same as in the synthesis of 2.8 (reaction time
was 3 h). Analysis of the recovered 2.8-d
4
by
1
H NMR spectroscopy showed partial deuteration (up to 34%)
of protons with chemical shifts at 6.62, –7.51, –13.87, and –19.99 ppm.

Figure 2.40.
1
H NMR spectrum of deuterated 2.8 in C
6
D
6
(hydride signals).
5.5 5.7 5.9 6.1 6.3 6.5 6.7 6.9 7.1 7.3 7.5 7.7 7.9 8.1 8.3 8.5 8.7 8.9
f1 (ppm)
1.02
1.06
0.66
0.99
1.05
0.94
1.00
-23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5
f1 (ppm)
0.72
0.73
0.73
Toluene, reflux, 3 h
KOH,
Ir Ir
N
P
H
H
Bu
t
Bu
t
CO
N
H
P
Bu
t
Bu
t
Ir Ir
N
P
D
D
Bu
t
Bu
t
CO
N
D
P
Bu
t
Bu
t
D
2.8
OD
D D
2.8-d
4
Ir Ir
N
P
D
D
Bu
t
Bu
t
CO
N
D
P
Bu
t
Bu
t
D
Ir Ir
N
P
D
D
Bu
t
Bu
t
CO
N
D
P
Bu
t
Bu
t
D
34%
86
2.4.7. Comparison of the Catalytic Activity of 2.2 and 2.8
In a glovebox, iridium complex 2.2 (5.5 mg, 8 x 10
-6
mol) or 2.8 (3.6 mg, 4 x 10
-6
mol), potassium
hydroxide (123.0 mg, 2.2 mmol), and benzyl alcohol (216.0 mg, 2.0 mmol) were mixed with dry toluene
(10 mL) in a 50 mL round-bottom flask charged with a stirring bar. The flask was equipped with reflux
condenser and eudiometer. The reaction mixture was actively stirred at reflux (oil bath, 120
o
C), collecting
hydrogen gas in the eudiometer. According to the eudiometry data (Figure 2.41), the kinetic profiles of
benzyl alcohol dehydrogenation with complexes 2.2 and 2.8 are identical within the experimental error.
Observed rate constants k
obs
were determined as the kinetic curve slopes and are equal to 29.1 ± 0.4 and
30.2 ± 0.3 mL/h for 2.2 and 2.8 respectively.
Figure 2.41. Hydrogen evolution profiles of benzyl alcohol dehydrogenation with complexes 2.2 and 2.8.
OH
2.2 or 2.8, KOH
+ 2H
2
Toluene, reflux
CO
2
K
2.8 2.2
87
2.4.8. Conversion of 2.8 to 2.11
A solution of 2.8 (20.0 mg, 2.25 x 10
-5
mol) and freshly distilled n-hexanal (22.5 mg, 2.25 x 10
-4
mol,
10 eq.) in C
6
D
6
(0.5 mL) was placed in a J. Young NMR tube and heated in an oil bath at 80
o
C for two
days. The resulting solution contained 2.11, n-hexanol, hexyl hexanoate, and unreacted n-hexanal. The
solution was evaporated to dryness under vacuum giving crude 2.11 as a dark-yellow oil. The structure
of 2.11 was derived from the following NMR data.
1
H NMR (600 MHz, toluene-d
8
): δ 8.18 (dd, J = 4.7, 1.7 Hz, 1H, ArH), 7.43 (dd, J = 7.6, 2.6 Hz, 1H,
ArH), 6.81 (t, J = 7.6 Hz, 1H, ArH), 6.76 (dd, J = 7.5, 1.8 Hz, 1H, ArH), 6.53 (d, J = 7.5 Hz, 1H, ArH), 6.36 (dd,
J = 7.5, 4.7 Hz, 1H, ArH), 3.76 (dd, J = 16.6, 9.2 Hz, 1H, CH
2
), 3.60 (dd, J = 16.6, 9.5 Hz, 1H, CH
2
), 2.41 (d, J
= 8.7 Hz, 2H, CH
2
), 1.37 (d, J = 13.1 Hz, 9H, 3CH
3
), 1.20 (d, J = 12.8 Hz, 9H, 3CH
3
), 1.06 (d, J = 13.9 Hz, 9H,
3CH
3
), 0.96 (d, J = 14.0 Hz, 9H, 3CH
3
), –8.44 (ddd, J = 52.5, 7.3, 5.2 Hz, 1H, IrH), –11.15 (ddd, J = 25.9,
12.6, 5.2 Hz, 1H, IrH).
31
P{
1
H} NMR (243 MHz, toluene-d
8
): δ 88.18, 44.46.
MALDI-MS: m/z calcd. for C
29
H
48
Ir
2
N
2
OP
2
[M]
+
886.25, found 886.25.
Figure 2.42.
1
H NMR spectrum of the reaction between 2.8 and n-hexanal (C
6
D
6
, 25
o
C).
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
3.78
1.96
4.25
2.00
7.16 Benzene
1-Hexanol
Hexyl
hexanoate
n-Hexanal
88
Figure 2.43.
1
H and
31
P{
1
H} NMR spectra of crude 2.11 in toluene-d
8
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
10.50
11.33
15.61
12.76
2.13
1.08
1.00
2.25
1.22
1.11
1.04
0.99
0.93
0.96
1.03
1.05
1.15
1.17
1.34
1.37
2.08 Toluene
2.35
2.37
3.62
3.64
3.65
3.67
3.81
3.82
3.84
3.86
6.42
6.43
6.43
6.44
6.46
6.47
6.76
6.77
6.79
6.87
6.87
6.89
6.89
7.52
7.53
8.31
8.31
8.32
8.32
-12 -11 -10 -9 -8 -7
f1 (ppm)
1.01
1.02
-11.06
-11.05
-11.03
-11.02
-11.01
-11.00
-10.98
-10.97
-8.37
-8.36
-8.36
-8.34
-8.26
-8.25
-8.25
-8.24
-100 -80 -60 -40 -20 0 20 40 60 80 100 120 140 160 180
f1 (ppm)
44.59
88.19
2.11
Ir Ir
P
H
P
H
CO N
N
tBu
tBu
tBu
tBu
89
2.4.9. Deprotonation of 2.8
t-BuOK (12.6 mg, 1.13 x 10
-4
mol, 5 eq.) was added to a solution of 2.8 (20.0 mg, 2.25 x 10
-5
mol) in
C
6
D
6
(0.5 mL) which caused formation of 2.12 and instant color change from yellow to dark-red. Addition
of n-hexanol (23.0 mg, 2.25 x 10
-4
mol, 10 eq.) to the red solution converted 2.12 back to 2.8. These
transformations were monitored by
1
H NMR.
Figure 2.44. Reversible deprotonation of 2.8 in C
6
D
6
monitored by
1
H NMR.
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5
f1 (ppm)
2.8
2.8 + t-BuOK
2.8 + t-BuOK + 1-hexanol
90
2.4.10. Dehydrogenation of Benzaldehyde
In a glovebox, iridium complex 2.1 (2.5 mg, 4 x 10
-6
mol), potassium hydroxide (123.0 mg, 2.2
mmol), and benzaldehyde (212.0 mg, 2.0 mmol) were mixed with dry toluene (10 mL) in a 50 mL round-
bottom flask charged with a stirring bar. The flask was equipped with reflux condenser and eudiometer.
The reaction mixture was actively stirred at reflux (oil bath, 120
o
C), collecting hydrogen gas in the
eudiometer. According to eudiometry data (Figure 2.45), the reaction has initiation delay of 30 min
followed by steady hydrogen evolution (k
obs
= 8.00 ± 0.07 mL/h). After the reaction was over, the
products were analyzed by
1
H NMR spectroscopy. The reaction mixture contains potassium benzoate
(91%) and benzyl alcohol (9%).
Figure 2.45. Hydrogen evolution profile of benzaldehyde dehydrogenation.
CHO
2.1, KOH
+ H
2
Toluene, reflux
CO
2
K
91
2.4.11. Formation of 1-Butoxyhexan-1-ol
In a glovebox, n-hexanal (10 mg, 1 x 10
-4
mol), 1-butanol (15 mg, 2 x 10
-4
mol), potassium hydroxide
(5 mg, 8.9 x 10
-5
mol), and toluene-d
8
(0.5 mL) were placed in a J. Young NMR tube. The tube was taken
out of the glovebox, heated at reflux for 5 min, then cooled to room temperature, and the resulting
solution was analyzed by NMR.
Figure 2.46.
1
H NMR spectra demonstrating formation of 1-butoxyhexan-1-ol.
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
CHO
+
OH
KOH (cat.)
Toluene
OH
O
H
OH
O
H
Before heating
After heating
92
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bis(diphenylphosphino)methane]. Organometallics 1992, 11, 3659−3664.
95
27. Olsen, E. P. K.; Madsen, R. Iridium-Catalyzed Dehydrogenative Decarbonylation of Primary Alcohols
with the Liberation of Syngas. Chem. Eur. J. 2012, 18, 16023–16029.
28. Olsen, E. P. K.; Singh, T.; Harris, P.; Andersson, P. G.; Madsen R. Experimental and Theoretical
Mechanistic Investigation of the Iridium-Catalyzed Dehydrogenative Decarbonylation of Primary
Alcohols. J. Am. Chem. Soc. 2015, 137, 834–842.
29. Melnick, J. G.; Radosevich, A. T.; Villagran, D.; Nocera, D. G. Decarbonylation of Ethanol to Methane,
Carbon Monoxide and Hydrogen by a [PNP]Ir Complex. Chem. Commun. 2010, 46, 79–81.
30. Kloek, S. M.; Heinekey, D. M.; Goldberg, K. I. Stereoselective Decarbonylation of Methanol to Form a
Stable Iridium(III) trans-Dihydride Complex. Organometallics 2006, 25, 3007–3011.
31. Cotton, F. A.; Poli, R. Ortho Metalation of Pyridine at a Diiridium Center. Synthesis and Spectroscopic
and Crystallographic Characterization of NC
5
H
4
- and N,N'-Di-p-tolylformamidinato-Bridged
Complexes of Diiridium(II). Organometallics 1987, 6, 1743−1751.
32. Takahashi, Y.; Nonogawa, M.; Fujita, K.; Yamaguchi, R. C–H Activation on a Diphosphine and Hydrido-
Bridged Diiridium Complex: Generation and Detection of an Active Ir
II
–Ir
II
Species [(Cp*Ir)
2
(μ-
dmpm)(μ-H)]
+
. Dalton Trans. 2008, 3546–3552.
33. Iali, W.; Green, G. G. R.; Hart, S. J.; Whitwood, A. C.; Duckett, S. B. Iridium Cyclooctene Complex That
Forms a Hyperpolarization Transfer Catalyst before Converting to a Binuclear C–H Bond Activation
Product Responsible for Hydrogen Isotope Exchange. Inorg. Chem. 2016, 55, 11639−11643.
34. Zell, T.; Milstein, D. Hydrogenation and Dehydrogenation Iron Pincer Catalysts Capable of Metal–
Ligand Cooperation by Aromatization/Dearomatization. Acc. Chem. Res. 2015, 48, 1979−1994.
96
Chapter 3. Catalyst Evolution in Iridium-Catalyzed Dehydrogenation of Formic
Acid
3.1. Introduction
In 2016, an iridium-based catalytic system was reported that enables conversion of neat formic acid
to CO
2
and H
2
(Scheme 3.1).
1
The catalytic system is reusable and air-tolerant, it operates under mild
conditions, affords millions of turnovers and high selectivity. The original work provides an interesting and
complex mechanism of the catalyst operation, which is based on synthetic and kinetic studies.
Here we report a follow-up work focusing on the mechanism of complex 3.1 speciation that governs
the catalytic dehydrogenation of formic acid. The synthetic, structural, and mechanistic data presented in
this work serve as a logical extension to the complex chemistry of 3.1 observed in catalytic primary alcohol
dehydrogenation process.
2
Scheme 3.1. Dehydrogenation of formic acid catalyzed by complex 3.1.
3.2. Results and Discussion
3.2.1. Synthesis of Catalytic Intermediates
We began the investigation of 3.1 speciation in formic acid dehydrogenation with isolation and
characterization of a series of catalytically relevant iridium complexes. Initially, we found that treatment
of complex 3.1 with a mixture of sodium formate and formic acid at 115
o
C for 15 min gives complex 3.3
as colorless crystals in 60% yield (Scheme 3.2).
HCOOH
HCOONa (5 mol%), 90
o
C
TON > 2 million
CO
2
+ H
2
Ir
N
OTf
P
tBu tBu
3.1 (50 ppm)
97
Scheme 3.2. Synthesis of intermediate 3.3.
The structure of 3.3 was established by single crystal X-ray diffraction (Figure 3.1). The dinuclear
complex features two bridging formate ligands, one bridging and two terminal hydrides, thus enabling
octahedral coordination geometry of iridium(III) atoms. To date, this is the second reported case of an
iridium formate complex, while the first one was a pincer-type complex containing η
1
-formate
[(PNP)IrH
2
(OOCH)].
3
The presence of the three hydride ligands was confirmed by
1
H NMR spectroscopy:
the corresponding peaks appear at –19.55 (ddd), –24.93 (d), and –26.53 (dd) ppm in CD
2
Cl
2
solution. The
two inequivalent phosphorus atoms are represented in
31
P{
1
H} NMR spectrum as a multiplet at 53.04 –
52.59 ppm rather than two separate singlets, which is due to inefficient P–H decoupling. Surprisingly, 3.3
is an air-stable compound, unlike other iridium complexes described in this work.

Figure 3.1. Molecular structures of the cations of 3.3 (left) and 3.5 (right) shown with 50% probability
ellipsoids. Hydrogen atoms are omitted for clarity, except for localized hydrides.
During the synthesis of 3.3 there was a formation of a dark-red iridium-containing by-product 3.5.
To afford its preparative synthesis, the conditions of the reaction among 3.1, sodium formate, and formic
3.1
115
o
C, 15 min
HCOOH, HCOONa
Ir
P
N
tBu tBu
OTf
3.3 (60%)
Ir
P
tBu
tBu
OTf
Ir
P
tBu
tBu
N
O
H
O
H
O
H
O
N
98
acid had to be changed. The essential step here is a four-hour reaction at 90
o
C that enables 3.5 in 71%
yield (Scheme 3.3). Complex 3.3 can be converted to 3.5 in the same manner in 50% yield. The structure
of 3.5 was determined by single-crystal X-ray diffraction (Figure 3.1). The molecule contains two
carbonylated iridium atoms bridged by a hydride ligand. The square-planar geometry of iridium atoms
and the red color of 3.5 are consistent with iridium(I) oxidation state.
1
H and
31
P{
1
H} NMR experiments
show that the hydride ligand gives a triplet with
2
J
PH
= 56.4 Hz at –0.09 ppm, while the equivalent
phosphorus atoms resonate at 78.06 ppm.
Scheme 3.3. Synthesis of intermediate 3.5.
Decarbonylation of organic substrates, such as alcohols and aldehydes, by iridium complexes is well
documented.
4–7
However, less is known about iridium-induced formate or formic acid decarbonylation.
Nevertheless, this reaction generates a number of ruthenium
8,9
and rhodium
10–12
carbonyl complexes.
Decarbonylation of coordinated formate ligands is particularly facile on rhodium, taking place even at
room temperature.
3.2.2. Reactivity of Catalytic Intermediates
The next step of the project was figuring out the role of 3.3 in the sequence of precatalyst 3.1
evolution. A time-course study of 3.1 in a solution of HCOONa/HCOOH (5 mol%) at room temperature was
3.5
Ir
P CO
H N
tBu tBu
OTf
Ir
P OC
N
tBu
tBu
3.1
Ir
P
N
tBu
tBu OTf
3.3
Ir
P
tBu
tBu
OTf
Ir
P
tBu
tBu
N
O
H
O
H
O
H
O
N
1. HCOOH, HCOONa, 25
o
C, 1 h
2. 90
o
C, 4 h
3. reflux (-HCOOH)
1. HCOOH, 90
o
C, 4 h
2. reflux ( -HCOOH)
71%
50%
99
conducted and monitored by
31
P NMR spectroscopy (Figure 3.14). The data show that precatalyst 3.1
undergoes a sequence of transformations leading to species 3.2 (
31
P δ = 46.42 ppm), which ultimately
(after ca. 2 h) becomes a dominant iridium form (Scheme 3.4). At this point the minor component in the
mixture is complex 3.3. The molecular structure of 3.2 was established in a previous study
1
and it happens
to be an isomer of 3.3 with a higher symmetry. Despite structural similarity between 3.2 and 3.3 they
exhibit surprisingly different reactivity: while 3.3 can be isolated, 3.2 cannot exist in the absence of formic
acid.
Scheme 3.4. Generation of intermediates 3.2 and 3.3 at room temperature.
A deuteration experiment demonstrated an exchange between a formate ligand in 3.3 and formic
acid solvent, happening in a highly selective manner (Figures 3.16 – 3.18). In this experiment 3.3 was
dissolved in a solution of HCOONa/DCOOD (5 mol%) and after one day
1
H NMR data indicated complete
deuteration of one coordinated formate ligand (8.60 ppm) and one terminal hydride (–26.54 ppm) while
the other formate and hydrides remained intact. Unfortunately, the available NMR methods failed to
specify the sites of deuteration.
The time-course study was continued by heating at 90
o
C the mixture of 3.2 and 3.3, generated at
room temperature, and monitoring the process over the course of four hours. At this temperature formic
acid dehydrogenation becomes extremely fast producing large volume of H
2
and CO
2
, for this reason the
NMR tube was connected to the Schlenk line during the reaction at 90
o
C, and
31
P{
1
H} NMR spectra were
recorded at room temperature (Figure 3.2). The data illustrate an initial conversion of 3.2 to 3.3 followed
by emergence of a new catalytic species 3.4 (
31
P δ = 57.20 ppm), which becomes the only detectable form
3.2 (major)
Ir
Ir
P
O
H
O
H
O
H
O
3.1
25
o
C
HCOOH, HCOONa
Ir
P
N
tBu tBu
OTf
3.3 (minor)
Ir
P
tBu
tBu
Ir
P
tBu
tBu
N
O
H
O
H
O
H
O
N
N
P
tBu
tBu
N
tBu
tBu
+
100
of iridium after four hours. This experiment was repeated using pure 3.3 in formic acid as a starting
solution and obtained highly similar results, where complex 3.4 was the final product (Figure 3.15).
Surprisingly, in this case we also observe formation of 3.2 as an intermediate, suggesting that 3.2 and 3.3
equilibrate fast at high temperature.
Figure 3.2.
31
P{
1
H} NMR spectra of the reaction mixture demonstrating transformation of 3.2 to 3.4 at
90
o
C.
Complex 3.4 is unstable in the absence of formic acid, as its attempted isolation by removing formic
acid (either at 25
o
C or 115
o
C) resulted in generation of complex 3.5 (Scheme 3.5). Moreover, it was
demonstrated by
1
H and
31
P NMR that 3.4 can be regenerated by treating 3.5 with a solution of
HCOONa/HCOOH at room temperature (Figures 3.20 and 3.21). Therefore, complex 3.4 was characterized
by NMR in CD
2
Cl
2
solution, containing a small amount of HCOONa and HCOOH.
1
H NMR spectrum of 3.4
features one hydride peak at –21.00 ppm (d,
2
J
PH
= 17.4 Hz), one set of pyridine peaks, and two peaks of
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
f1 (ppm)
3.2
Before heating
5 min
30 min
1 hour
2 hours
4 hours
3.3
3.4
101
tert-butyl groups, suggesting chemical equivalence of the (PN)IrH fragments in the dinuclear structure.
Carbonyl ligands in 3.4 are necessitated by their presence in 3.5. Overall, the proposed structure of 3.4
shown in Scheme 3.5 satisfies spectroscopic data and was supported by computational studies.
Scheme 3.5. Generation and degradation of the catalyst resting state 3.4.
The possibility to convert 3.5 to 3.4 and back is spectacular, since this could indicate their relevance
to the catalytic cycle of formic acid dehydrogenation. A stepwise catalytic cycle experiment was conducted
to take a closer look at the process, in which we monitored the sequence 3.5 → 3.4 → 3.5 by
1
H NMR
(Figure 3.24). At first, complex 3.5 in CD
2
Cl
2
was treated with HCOONa/HCOOH solution resulting in an
instant conversion to 3.4. Then, the J. Young NMR tube was sealed and left for three days at room
temperature. During this time formic acid fully converted to CO
2
and H
2
, while 3.4 converted to a mixture
of 3.5 and a new complex 3.5-H
2
. Complex 3.5-H
2
was characterized by two phosphorus peaks (
31
P δ =
89.87 and 69.56 ppm) and two multiplets corresponding to three hydride ligands (
1
H δ = –4.80 (1H), –8.34
(2H)). Finally, the tube was opened, and the content was heated at 45
o
C for 30 min to release hydrogen
gas from the system, which gave back complex 3.5 only.
The identity of 3.5-H
2
as a hydrogenated form of 3.5 was confirmed via direct reaction between 3.5
and hydrogen gas under ambient pressure in a CD
2
Cl
2
solution (Figure 3.23). NMR analysis suggests partial
consumption of 3.5 and generation of 3.5-H
2
, that was observed previously in the catalytic cycle
experiment (Scheme 3.6). In the absence of hydrogen 3.5-H
2
converts back to 3.5. The structure of 3.5-H
2

was not proposed, since there are many possible isomers that could be formed with this particular set of
ligands.
3.5
Ir
P CO
H N
tBu tBu
Ir
P OC
N
tBu
tBu
25
o
C
3.4
Ir
P CO
N
Ir
P OC
N
O
O
H
H
3.1
Ir
P
N
tBu
tBu
HCOOH
HCOONa
1. HCOOH,
HCOONa
25
o
C, 1 h
2. 90
o
C, 4 h
tBu
tBu
tBu
tBu
Removal of HCOOH
102
Scheme 3.6. Reactions of Intermediate 3.5.
Prolonged heating of complex 3.5 in the absence of formic acid affords its isomer 3.6, which is the
product of intramolecular oxidative addition of pyridine C–H bond across diiridium core (Scheme 3.6).
Complex 3.6 was isolated and its structure was established based on
1
H,
19
F,
31
P NMR, and MALDI-MS
spectroscopy.
1
H NMR spectrum contains only seven aromatic peaks suggesting one ortho-metallated
pyridine fragment and two hydride ligands resonating at –7.60 (ddd) and –9.78 (dt) ppm.
19
F and
31
P NMR data are consistent with triflate anion and two different phosphine ligands (
31
P δ = 89.91
and 57.57 ppm). Complex 3.6 is most likely irrelevant to the catalytic formic acid dehydrogenation,
however its unique structure makes an exciting connection between two stories on how 3.1 activates by
formic acid and by primary alcohols.
2
3.2.3. Mechanism of Precatalyst Activation
A unifying scheme for the activation of complex 3.1 in catalytic formic acid dehydrogenation and the
corresponding catalytic cycle were proposed (Scheme 3.7). At room temperature complex 3.1 converts to
intermediate 3.2. At 90
o
C 3.2 equilibrates with its isomer 3.3 and undergoes a slow decarbonylation of
coordinated formates over the course of four hours to give the catalyst resting state 3.4. The following
steps of the catalytic cycle do not require high temperature and can operate even at room temperature,
although slowly. Thus, 3.4 releases CO
2
to form complex 3.5-H
2
, which dehydrogenates to give 3.5. If
formic acid is present in the system, it oxidatively adds to 3.5 to regenerate 3.4.
3.5
Ir
P CO
H N
tBu tBu
OTf
Ir
P OC
N
tBu
tBu
N
Ir Ir
CO
P
tBu
tBu
H
H
P
OC
N
tBu
tBu OTf
110
o
C
H
2
(1 atm)
3.5-H
2
3.6
103
Scheme 3.7. Proposed mechanism of 3.1 activation and the catalytic cycle. tert-Butyl groups are omitted
for clarity.
3.3. Conclusions
A detailed study on the precatalyst 3.1 evolution in iridium-catalyzed formic acid dehydrogenation
was conducted. The study revealed a series of catalytic species 3.2 – 3.6. Complexes 3.2 and 3.3 are
precatalytic intermediates, 3.4 is the catalyst resting state, 3.5-H
2
is the hydrogenated form of catalyst,
3.5 can be qualified as dehydrogenated or post-catalytic form, and 3.6 is the product of 3.5 thermal
isomerization. Elaborate time-course NMR studies suggest a slow carbonylation of iridium at high
temperature as a key step for generating the active catalyst 3.4 that can dehydrogenate formic acid even
at room temperature. Overall, a number of synthetic experiments were conducted that refined the
understanding of the catalyst evolution mechanism governing the highly efficient formic acid
dehydrogenation process.
3.1
Ir
P
N
3.2
Ir
P
Ir
P
N
O
H
O
H
O
H
O
N
25
o
C
3.3
3.5
Ir
P CO
H N
Ir
P OC
N
90
o
C, slow
3.5-H
2
- H
2
+ H
2
- CO
2
HCOOH
HCOONa
Ir
P
Ir
N
N
O
H
O
H
O
H
O
P
3.4
Ir
P CO
N
Ir
P OC
N
O
O
H
H
HCOOH
(fast at 90
o
C)
HCOOH
HCOONa
HCOOH
HCOONa
104
3.4. Experimental Section
3.4.1. Materials and Methods
Complex 3.1 was synthesized according to published procedure.
1
Formic acid-d
2
and CD
2
Cl
2
were
purchased from Cambridge Isotope Laboratories. Hexane, CH
2
Cl
2
, Et
2
O, and THF were dried using a solvent
purification system. All reactions were conducted under nitrogen either in a Vacuum Atmospheres
glovebox (0-5 ppm O
2
) or outside the glovebox using the Schlenk line.
1
H,
13
C,
19
F, and
31
P NMR spectra
were acquired on Varian Mercury 400, VNMRS-500, and VNMRS-600 spectrometers and processed using
MestReNova 12.0.1. All chemical shifts are reported in ppm and referenced to the residual
1
H or
13
C
solvent peaks. Following abbreviations are used: (s) singlet, (bs s) broad singlet, (d) doublet, (t) triplet,
(dd) doublet of doublets, etc. NMR spectra of all metal complexes were taken in 8” J. Young tubes (Wilmad
or Norell) with Teflon valve plugs. MALDI-MS spectra were acquired on Bruker Autoflex Speed MALDI
Mass Spectrometer. Infrared spectra were recorded on Bruker OPUS FTIR spectrometer.
3.4.2. Synthesis of Iridium Complexes
[Ir
2
H
3
(HCOO)
2
(PyCH
2
PBu
t
2
)
2
]OTf (3.3). A solution of complex 3.1 (500 mg, 7.28 x 10
–4
mol) and sodium
formate (500 mg, 7.35 mmol, 10 eq.) in formic acid (5 mL) was stirred at room temperature under nitrogen
for 30 min. When the solution became yellow, it was heated in an oil bath (115
o
C) until all formic acid
decomposed and the mixture turned to an orange solid. The residue was mixed with K
2
CO
3
(400 mg) and
CH
2
Cl
2
(10 mL) and stirred for one hour to neutralize traces of formic acid. The precipitate was filtered off
and washed with CH
2
Cl
2
(10 mL). The combined dichloromethane solution was evaporated to dryness and
then dissolved in THF (2 mL). After a few days the product crystallized as off-white crystals. It was filtered
and recrystallized from CH
2
Cl
2
/hexane to give colorless crystals (240 mg, 60%). Crystals suitable for X-ray
analysis were obtained by slow evaporation of CH
2
Cl
2
/hexane solution.
105
1
H NMR (600 MHz, CD
2
Cl
2
): δ 9.21 (d, J = 5.7 Hz, 1H, Py), 9.08 (d, J = 5.9 Hz, 1H, Py), 8.60 (dd, J = 9.3,
3.1 Hz, 1H, HCOO), 7.94 (t, J = 7.7 Hz, 1H, Py), 7.71 (d, J = 3.6 Hz, 1H, Py), 7.70 – 7.66 (m, 2H, Py, HCOO),
7.52 (d, J = 7.8 Hz, 1H, Py), 7.44 (t, J = 6.7 Hz, 1H, Py), 6.92 (t, J = 6.8 Hz, 1H, Py), 3.72 (dd, J = 16.8, 10.1 Hz,
1H, CH
2
), 3.64 (dd, J = 17.1, 10.2 Hz, 1H, CH
2
), 3.31 (dd, J = 16.9, 9.7 Hz, 1H, CH
2
), 3.20 (dd, J = 16.8, 9.3 Hz,
1H, CH
2
), 1.47 (d, J = 14.2 Hz, 9H, 3Me), 1.28 (d, J = 14.1 Hz, 9H, 3Me), 1.26 (d, J = 11.7 Hz, 9H, 3Me), 1.02
(d, J = 13.8 Hz, 9H, 3Me), –19.55 (ddd, J = 49.0, 13.0, 2.9 Hz, 1H, µ-H), –24.93 (d, J = 16.2 Hz, 1H, IrH), –
26.53 (dd, J = 20.9, 3.3 Hz, 1H, IrH).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 180.10, 175.79, 167.40, 163.89, 159.68, 150.33, 138.64, 138.13,
123.92, 123.87, 123.41 (d, J = 8.7 Hz), 123.19 (d, J = 8.6 Hz), 37.91 (d, J = 30.0 Hz), 37.38, 37.31, 37.27,
37.12, 35.76 (d, J = 24.2 Hz), 34.65, 34.60, 34.45, 34.37, 30.00, 29.87, 28.57, 28.02.
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.92.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 53.04 – 52.59 (m, 2P).
IR (KBr, cm
-1
): 2960, 2907, 2869, 2304 (ν
IrH
), 2246 (ν
IrH
), 1880, 1608 (ν
COO
), 1483, 1351, 1276, 1265,
1159, 1032, 827, 776, 768, 639.
MALDI-MS: m/z calcd for [C
30
H
53
Ir
2
N
2
O
4
P
2
]
+
951.27, found 951.05.
106
Figure 3.3.
1
H NMR spectra of 3.3 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
9.09
19.00
9.23
1.00
1.00
1.09
1.15
0.99
0.95
0.99
1.96
0.79
0.95
0.74
0.99
0.92
1.01
1.03
1.25
1.27
1.29
1.46
1.48
3.18
3.19
3.20
3.22
3.29
3.30
3.31
3.33
3.62
3.64
3.65
3.67
3.70
3.72
3.73
3.75
6.91
6.92
6.93
7.43
7.44
7.45
7.52
7.53
7.67
7.68
7.69
7.71
7.71
7.93
7.94
7.95
8.59
8.60
8.61
8.61
9.08
9.09
9.21
9.22
-28.0 -27.0 -26.0 -25.0 -24.0 -23.0 -22.0 -21.0 -20.0 -19.0 -18.0
f1 (ppm)
1.00
0.99
0.99
-26.56
-26.56
-26.53
-26.52
-24.95
-24.92
-19.60
-19.60
-19.58
-19.58
-19.52
-19.52
-19.50
-19.50
107
Figure 3.4.
31
P{
1
H} NMR spectra of 3.3 in CD
2
Cl
2
(top) and HCOOH (bottom).
-30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
52.64
52.83
52.88
52.94
53.00
52.2 52.6 53.0 53.4
f1 (ppm)
52.64
52.83
52.88
52.94
53.00
49.0 49.5 50.0 50.5 51.0 51.5 52.0 52.5 53.0 53.5 54.0 54.5 55.0 55.5 56.0 56.5 57.0 57.5 58.0
f1 (ppm)
52.92
52.99
53.05
53.75
53.80
53.98
54.03
108
Figure 3.5. COSY NMR spectra of 3.3 in CD
2
Cl
2
.
6.6 6.8 7.0 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 9.0 9.2 9.4 9.6
f2 (ppm)
6.6
6.8
7.0
7.2
7.4
7.6
7.8
8.0
8.2
8.4
8.6
8.8
9.0
9.2
9.4
9.6
f1 (ppm)
-27.0 -26.5 -26.0 -25.5 -25.0 -24.5 -24.0 -23.5 -23.0 -22.5 -22.0 -21.5 -21.0 -20.5 -20.0 -19.5 -19.0
f2 (ppm)
-27
-26
-25
-24
-23
-22
-21
-20
-19
f1 (ppm)
109
Figure 3.6.
13
C{
1
H} NMR spectrum of 3.3 in CD
2
Cl
2
.
Figure 3.7.
19
F NMR spectrum of 3.3 in CD
2
Cl
2
.
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
28.02
28.57
29.87
30.00
34.37
34.45
34.60
34.65
35.68
35.84
37.12
37.27
37.31
37.38
37.81
38.01
53.84 Dichloromethane
123.16
123.22
123.38
123.44
123.87
123.92
138.13
138.64
150.33
159.68
163.89
167.40
175.79
180.10
-85 -84 -83 -82 -81 -80 -79 -78 -77 -76 -75 -74 -73 -72 -71 -70 -69
f1 (ppm)
-78.92
110
[Ir
2
D
2
(DCOO)(CO)
2
(PyCH
2
PBu
t
2
)
2
]
+
(3.4-d
3
). Complex 3.4-d
3
was generated and characterized by NMR
in a solution prepared by combining complex 3.5 (15 mg, 1.30 x 10
–5
mol), sodium formate (45 mg, 6.62 x
10
–4
mol), and formic acid-d
2
(610 mg, 12.7 mmol) at room temperature.
1
H NMR (500 MHz, DCOOD/HCOONa): δ 8.85 (d, J = 5.3 Hz, 2H, ArH), 8.15 (t, J = 7.5 Hz, 2H, ArH), 7.91
(d, J = 7.8 Hz, 2H, ArH), 7.61 (t, J = 6.3 Hz, 2H, ArH), 4.03 (dd, J = 17.1, 10.7 Hz, 2H, CH
2
), 3.88 (dd, J = 17.0,
11.9 Hz, 2H, CH
2
), 1.45 – 1.23 (m, 36H, 12Me). Peaks of the hydride and formate ligands are invisible due
to their deuteration.
13
C{
1
H} NMR (126 MHz, DCOOD/HCOONa): δ 163.21 (d,
2
J
CP
= 8.3 Hz, CO), 161.87, 148.87, 141.62,
124.22 (d, J = 9.4 Hz), 124.05, 119.55 (q,
1
J
CF
= 317.2 Hz, CF
3
), 36.11 (d, J = 3.2 Hz), 35.88 (d, J = 9.0 Hz),
33.71 (d, J = 31.3 Hz, CH
2
), 27.72, 27.50. A peak of the formate ligands is invisible due to its deuteration.
31
P{
1
H} NMR (202 MHz, DCOOD/HCOONa): δ 55.46 (s).
Figure 3.8.
1
H NMR spectrum of 3.4-d
3
in DCOOD/HCOONa. The sample was preheated for 10 minutes at
100
o
C to converge organic byproducts to a single compound that gives extra peaks at 4.24 (s) and 0.91 (t).
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0
f1 (ppm)
37.79
2.12
2.22
2.00
2.17
2.02
1.78
1.32
1.35
1.37
3.85
3.88
3.89
3.91
4.00
4.02
4.04
4.06
7.60
7.62
7.63
7.90
7.92
8.14
8.15
8.17
8.30 Formic Acid
8.84
8.86
111
Figure 3.9.
13
C{
1
H} and
31
P{
1
H} NMR spectra of 3.4-d
3
in DCOOD/HCOONa.
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
27.50
27.72
33.59
33.84
35.84
35.91
36.09
36.12
115.76
118.29
120.81
123.33
124.05
124.18
124.26
141.62
148.87
161.87
163.17
163.24
166.00 Formic Acid-d2
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95
f1 (ppm)
55.46
112
[Ir
2
H(CO)
2
(PyCH
2
PBu
t
2
)
2
]OTf · CH
2
Cl
2
(3.5). Method 1: A solution of complex 3.3 (100 mg, 9.08 x 10
–5

mol) in formic acid (5 mL) was heated at 90
o
C for 4 hours in an open reactor under nitrogen. Then the
solvent was removed by distillation (115
o
C) to give a red glassy solid. The residue was dissolved in CH
2
Cl
2

and the equal volume of hexane was added to produce a clear red solution. After a few days well-formed
dark-red crystals were formed. They were separated from the liquid, washed with hexane and dried in
vacuum (52 mg, 50%). Crystals suitable for X-ray analysis were obtained by slow evaporation of
CH
2
Cl
2
/hexane solution.
Method 2: A solution of complex 3.1 (200 mg, 2.91 x 10
–4
mol) and sodium formate (99 mg, 1.46
mmol, 5 eq.) in formic acid (20 mL) was stirred at room temperature under nitrogen for one hour. When
the solution became yellow, it was heated in an oil bath for 4 hours at 90
o
C. Then, the temperature was
raised to 115
o
C, and the remaining formic acid was distilled off affording a red solid. The solid was
extracted with CH
2
Cl
2
, filtered, and the resulting black-red solution was diluted with diethyl ether. The
next day the product crystallized as dark-red crystals. They were filtered, washed with diethyl ether, and
dried in vacuum (118 mg, 71%).
1
H NMR (500 MHz, CD
2
Cl
2
): δ 9.74 (d, J = 5.3 Hz, 2H, ArH), 7.96 (t, J = 7.6 Hz, 2H, ArH), 7.77 (d, J = 7.7
Hz, 2H, ArH), 7.28 (t, J = 6.4 Hz, 2H, ArH), 5.33 (s, 2H, CH
2
Cl
2
), 3.75 (d, J = 8.2 Hz, 4H, 2CH
2
), 1.41 (d, J = 13.7
Hz, 36H, 12CH
3
), –0.09 (t,
2
J
PH
= 56.4 Hz, 1H, IrH).
13
C{
1
H} NMR (126 MHz, CD
2
Cl
2
): δ 179.13, 166.74, 160.82, 140.51, 124.31, 124.02 (t, J = 4.8 Hz), 37.24
– 36.64 (m), 36.21 – 35.76 (m), 29.22.
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.89.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 78.06 (s).
IR (KBr, cm
-1
): 2965, 2905, 2874, 2043, 1960 (ν
CO
), 1612, 1479, 1274, 1151, 1034, 829, 770, 640.
MALDI-MS: m/z calcd for [C
30
H
49
Ir
2
N
2
O
2
P
2
]
+
915.25, found 915.21.
113
Figure 3.10.
1
H and
13
C{
1
H} NMR spectra of 3.5 in CD
2
Cl
2
.
-1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0
f1 (ppm)
1.00
40.16
4.05
1.73
2.03
2.09
2.02
2.02
-0.20
-0.09
0.02
1.40
1.43
3.74
3.76
5.33
7.27
7.28
7.30
7.76
7.78
7.94
7.96
7.97
9.73
9.74
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
29.22
36.07
37.04
53.84 Dichloromethane
124.02
124.31
140.51
160.82
166.74
179.13
114
Figure 3.11.
19
F (top) and
31
P{
1
H} (bottom) NMR spectra of 3.5 in CD
2
Cl
2
.
-200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20
f1 (ppm)
-78.89
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
78.06
115
[Ir
2
H
2
(CO)
2
(PyCH
2
PBu
t
2
)(µ-PyCH
2
PBu
t
2
)]OTf (3.6). The filtrate obtained in the synthesis of complex 3.5
(method 1) was diluted with hexane and left for slow evaporation in a closed vial. After a few days several
yellow crystals were formed, they were separated from the solution, washed with hexane and dried in
vacuum.
1
H NMR (600 MHz, CD
2
Cl
2
): δ 7.83 (t, J = 7.7 Hz, 1H, ArH), 7.72 (d, J = 7.9 Hz, 1H, ArH), 7.63 (d, J = 5.2
Hz, 1H, ArH), 7.60 (t, J = 7.4 Hz, 1H, ArH), 7.51 (dd, J = 7.3, 2.3 Hz, 1H, ArH), 7.47 (d, J = 7.7 Hz, 1H, ArH),
6.91 (t, J = 6.7 Hz, 1H, ArH), 3.86 (dd, J = 17.1, 9.7 Hz, 1H, CH
2
), 3.71 (dd, J = 17.2, 9.2 Hz, 1H, CH
2
), 3.30 –
3.14 (m, 2H, CH
2
), 1.49 (d, J = 14.5 Hz, 9H, 3CH
3
), 1.45 (d, J = 14.3 Hz, 9H, 3CH
3
), 1.39 (d, J = 14.5 Hz, 9H,
3CH
3
), 1.33 (d, J = 14.6 Hz, 9H, 3CH
3
), –7.60 (ddd, J = 43.2, 10.9, 7.4 Hz, 1H, IrH), –9.78 (dt, J = 25.3, 11.4
Hz, 1H, IrH).
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.92.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 89.91, 57.57.
MALDI-MS: m/z calcd for [C
30
H
49
Ir
2
N
2
O
2
P
2
]
+
915.25, found 915.20.
Figure 3.12.
19
F (top) and
31
P{
1
H} (bottom) NMR spectra of 3.6 in CD
2
Cl
2
.
-200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20
f1 (ppm)
-78.92
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125
f1 (ppm)
57.57
89.91
116
Figure 3.13.
1
H NMR spectra of 3.6 in CD
2
Cl
2
.
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0
f1 (ppm)
9.86
10.01
9.66
9.96
2.17
1.11
1.08
0.94
0.93
0.96
0.95
0.94
0.96
0.92
1.31
1.34
1.38
1.40
1.44
1.46
1.47
1.50
3.17
3.26
3.69
3.74
3.83
3.88
5.32 Dichloromethane
6.91
7.47
7.48
7.51
7.52
7.60
7.63
7.63
7.72
7.73
7.83
-10.2 -10.0 -9.8 -9.6 -9.4 -9.2 -9.0 -8.8 -8.6 -8.4 -8.2 -8.0 -7.8 -7.6 -7.4 -7.2
f1 (ppm)
1.05
1.00
-9.82
-9.80
-9.79
-9.78
-9.76
-9.74
-7.65
-7.63
-7.63
-7.62
-7.57
-7.56
-7.56
-7.54
117
3.4.3. Conversion of 3.1 to 3.2 in HCOONa/HCOOH Solution at Room Temperature
Complex 3.1 (30 mg, 4.37 x 10
–5
mol) was dissolved in a 5 mol% solution of HCOONa in HCOOH (0.5
mL) and the reaction progress was monitored by
31
P{
1
H} NMR at room temperature. Four spectra were
recorded over the course of two hours, demonstrating slow conversion of 3.1 to 3.2. Complex 3.3 was
detected as a minor component during the conversion.
Figure 3.14.
31
P{
1
H} NMR spectra demonstrating conversion of 3.1 to 3.2 at room temperature.
3.4.4. Conversion of 3.2 to 3.4 in HCOONa/HCOOH Solution at 90
o
C
Complex 3.1 (30 mg, 4.37 x 10
–5
mol) was dissolved in a 5 mol% solution of HCOONa in HCOOH (0.5
mL) and the resulting solution was kept for 2 hours at room temperature to generate complex 3.2. Further
evolution of the catalyst was conducted at 90
o
C (oil bath, open J. Young NMR tube) and monitored by
31
P{
1
H} NMR at room temperature. Over the course of four hours complex 3.2 undergoes conversion to
3.3 and, ultimately, to 3.4.
20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74
f1 (ppm)
3.1
10 min
25 min
70 min
130 min
3.2
3.3
118
3.4.5. Conversion of 3.3 to 3.4 in HCOOH solution at 90
o
C
A solution of complex 3.3 (15 mg, 1.36 x 10
–5
mol) in HCOOH (0.5 mL) was heated at 90
o
C (oil bath,
open J. Young NMR tube) and the reaction progress was monitored by
31
P{
1
H} NMR at room temperature.
Over the course of four hours complex 3.3 undergoes conversion to 3.2 and, ultimately, to 3.4.
Figure 3.15.
31
P{
1
H} NMR spectra demonstrating conversion of 3.3 to 3.4 at 90
o
C.
43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
f1 (ppm)
3.3
Before heating
5 min
1 hour
2 hours
4 hours
3.2
3.4
119
3.4.6. Selective Deuteration of 3.3 in HCOONa/DCOOD Solution at Room Temperature
Complex 3.3 (15 mg, 1.36 x 10
–5
mol) and sodium formate (45 mg, 6.62 x 10
–4
mol) were dissolved in
formic acid-d
2
(610 mg, 12.7 mmol) and the resulting solution was kept for one day in a closed J. Young
NMR tube at room temperature.
1
H and
13
C NMR data suggest selective deuteration of one of the terminal
hydride ligands and one of the formate ligands.
Figure 3.16. Fragments of
1
H NMR spectra of complexes 3.3 and 3.3-d
2
demonstrating selective
deuteration of the formate ligand resonating at 8.60 ppm.
6.3 6.5 6.7 6.9 7.1 7.3 7.5 7.7 7.9 8.1 8.3 8.5 8.7 8.9 9.1 9.3 9.5 9.7 9.9 10.1
f1 (ppm)
25
o
C, 24 h
DCOOD
3.3
HCOONa (5 mol%)
Ir
P
Ir
N
N
O
H
O
H
O
H
O
P
3.3-d
2
Ir
P
Ir
N
N
O
H
O
D
O
H
O
P
D
Complex 3.3
Complex 3.3-d
2
120
Figure 3.17. COSY NMR spectrum of complex 3.3-d
2
demonstrating persistence of the formate ligand
resonating at 7.76 ppm.
Figure 3.18. Fragments of
1
H NMR spectra of complexes 3.3 and 3.3-d
2
demonstrating selective
deuteration of the terminal hydride ligand resonating at –26.54 ppm.
6.7 6.9 7.1 7.3 7.5 7.7 7.9 8.1 8.3 8.5 8.7 8.9 9.1 9.3 9.5
f2 (ppm)
7.0
7.5
8.0
8.5
9.0
9.5
f1 (ppm) -29.5 -28.5 -27.5 -26.5 -25.5 -24.5 -23.5 -22.5 -21.5 -20.5 -19.5 -18.5 -17.5 -16.5
f1 (ppm)
Complex 3.3
Complex 3.3-d
2
*
*
121
3.4.7. Conversion of 3.3-d
2
to 3.2-d
n
in HCOONa/DCOOD Solution at Room Temperature
Complex 3.3 (15 mg, 1.36 x 10
–5
mol) and sodium formate (45 mg, 6.62 x 10
–4
mol) were dissolved in
formic acid-d
2
(610 mg, 12.7 mmol) and the resulting solution was kept for one day in a closed J. Young
NMR tube at room temperature to generate complex 3.3-d
2
. According to
31
P NMR, 3.3-d
2
slowly
isomerizes to 3.2-d
n
at room temperature, and the reaction equilibrium seems to be reached after 23
days. Integration of the corresponding peaks in the
31
P NMR spectrum (acquired with 5 sec relaxation
delay) gives the estimated value of the equilibrium constant K
eq
= [3.2-d
n
]/[3.3-d
2
] = 0.146.
Figure 3.19.
31
P{
1
H} NMR spectrum demonstrating complexes 3.2-d
n
and 3.3-d
2
at equilibrium in
HCOONa/DCOOD solution.
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
f1 (ppm)
1.00
6.87
25
o
C, 23 days
DCOOD
HCOONa (5 mol%)
3.3-d
2
Ir
P
Ir
N
N
O
H
O
D
O
H
O
P
D
3.2-d
n
3.3-d
2
3.2-d
n
122
3.4.8. Generation of 3.4 from 3.1 and 3.5
Experiment 1. Complex 3.1 (30 mg, 4.37 x 10
–5
mol) was dissolved in a 5 mol% solution of HCOONa
in HCOOH (0.5 mL) and the resulting solution was kept for 2 hours at room temperature to generate
complex 3.2. Then, the mixture was heated at 90
o
C until almost full decomposition of formic acid (oil
bath, open J. Young NMR tube). Then, the residue was dissolved in CD
2
Cl
2
(0.5 mL) and analyzed by
1
H and
31
P NMR.
Experiment 2. A 5 mol% solution of HCOONa in HCOOH (2 drops) was added to a solution of complex
3.5 (30 mg, 2.61 x 10
–5
mol) in CD
2
Cl
2
(0.5 mL) resulting in fast color change and formation of complex 3.4.
The obtained mixture was analyzed by
1
H and
31
P NMR.
Figure 3.20. Fragments of
1
H NMR spectra demonstrating identity of the solutions obtained in the
experiments 1 and 2. The hydride ligands of complex 3.4 resonate at –21.00 ppm (d,
2
J
PH
= 17.4 Hz).
-29 -28 -27 -26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1
f1 (ppm)
Experiment 1
Experiment 2
123
Figure 3.21. Fragments of
31
P{
1
H} NMR spectra demonstrating identity of the solutions obtained in
experiments 1 and 2. The peak of complex 3.4 appears at 55.08 ppm (d,
2
J
PH
= 14.6 Hz).
39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
f1 (ppm)
Experiment 1
Experiment 2
124
3.4.9. Conversion of 3.5 to 3.6
Complex 3.5 (30 mg, 2.61 x 10
–5
mol) was dissolved in a 5 mol% solution of HCOONa in HCOOH (0.1
mL) and heated at 110
o
C (oil bath) in an open J. Young NMR tube. After all formic acid decomposed the
reaction was continued overnight. During this period the initially red residue turned dark-yellow. Then, it
was dissolved in CD
2
Cl
2
(0.5 mL) and analyzed by
1
H and
31
P NMR.
Figure 3.22.
1
H (top) and
31
P{
1
H} (bottom) NMR spectra demonstrating formation of complex 3.6.
-27 -26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1
f1 (ppm)
0.96
1.00
-9.83
-9.81
-9.79
-9.78
-9.77
-9.75
-7.65
-7.64
-7.63
-7.62
-7.58
-7.56
-7.56
-7.55
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110
f1 (ppm)
57.57
89.95
125
3.4.10. Hydrogenation of 3.5
Complex 3.5 (30 mg, 2.61 x 10
–5
mol) was dissolved in CD
2
Cl
2
(0.5 mL) in J. Young NMR tube, then the
head space of the tube was filled with hydrogen gas at 1 atm. Content of the tube was shaken vigorously
followed by analysis via
1
H and
31
P NMR. The data suggest that 3.5 is partially hydrogenated to give a
major product 3.5-H
2
which is characterized by hydride and phosphine signals listed bellow.
1
H NMR (500 MHz, CD
2
Cl
2
): δ –4.80 (d, J = 131.3 Hz, 1H), –8.34 (d, J = 34.8 Hz, 2H).
31
P{
1
H} NMR (202 MHz, CD
2
Cl
2
): δ 89.87, 69.56.
Figure 3.23.
1
H and
31
P{
1
H} NMR spectra demonstrating formation of 3.5-H
2
.
-26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0
f1 (ppm)
1.78
1.00
-8.38
-8.31
-4.93
-4.67
52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96
f1 (ppm)
69.56
78.06
89.87
3.5
Ir
P CO
H N
tBu tBu
Ir
P OC
N
tBu
tBu
H
2
(1 atm)
CD
2
Cl
2
3.5-H
2
126
3.4.11. Stepwise Catalytic Cycle Experiment
To a solution of complex 3.5 (30 mg, 2.61 x 10
–5
mol) in CD
2
Cl
2
(0.5 mL) in J. Young NMR tube (Figure
3.24A) were added two drops of 5 mol% solution of HCOONa/HCOOH to give complex 3.4 (Figure 3.24B).
The tube was sealed, and after three days HCOOH was fully dehydrogenated, while 3.4 converted to a
mixture of 3.5 and 3.5-H
2
(Figure 3.24C). Then, the tube was opened, and the content was heated at 45
o
C for 30 min to release hydrogen gas from the system, which resulted in a clean formation of 3.5
(Figure 3.24D).
Figure 3.24.
1
H NMR spectra demonstrating sequential transformation 3.5 → 3.4 → 3.5-H
2
→ 3.5.
-26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0
f1 (ppm)
3.5
3.4
3.5-H
2
A
B
C
D
127
3.5. References
1. Celaje, J. J. A.; Lu, Z.; Kedzie, E. A.; Terrile, N. J.; Lo, J. N.; Williams, T. J. A Prolific Catalyst for
Dehydrogenation of Neat Formic Acid. Nature Com. 2016, 7, 11308.
2. Cherepakhin, V.; Williams, T. J. Iridium Catalysts for Acceptorless Dehydrogenation of Alcohols to
Carboxylic Acids: Scope and Mechanism. ACS Catal. 2018, 8, 3754–3763.
3. Schmeier, T. J.; Dobereiner, G. E.; Crabtree, R. H.; Hazari, N. Secondary Coordination Sphere
Interactions Facilitate the Insertion Step in an Iridium(III) CO
2
Reduction Catalyst. J. Am. Chem. Soc.
2011, 133, 9274–9277.
4. Olsen, E. P. K.; Madsen, R. Iridium-Catalyzed Dehydrogenative Decarbonylation of Primary Alcohols
with the Liberation of Syngas. Chem. Eur. J. 2012, 18, 16023–16029.
5. Olsen, E. P. K.; Singh, T.; Harris, P.; Andersson, P. G.; Madsen R. Experimental and Theoretical
Mechanistic Investigation of the Iridium-Catalyzed Dehydrogenative Decarbonylation of Primary
Alcohols. J. Am. Chem. Soc. 2015, 137, 834–842.
6. Melnick, J. G.; Radosevich, A. T.; Villagran, D.; Nocera, D. G. Decarbonylation of Ethanol to Methane,
Carbon Monoxide and Hydrogen by a [PNP]Ir Complex. Chem. Commun. 2010, 46, 79–81.
7. Kloek, S. M.; Heinekey, D. M.; Goldberg, K. I. Stereoselective Decarbonylation of Methanol to Form a
Stable Iridium(III) trans-Dihydride Complex. Organometallics 2006, 25, 3007–3011.
8. Czaun, M.; Goeppert, A.; Kothandaraman, J.; May, R. B.; Haiges, R.; Prakash, G. K. S.; Olah, G. A.
Formic Acid as a Hydrogen Storage Medium: Ruthenium-Catalyzed Generation of Hydrogen from
Formic Acid in Emulsions. ACS Catal. 2014, 4, 311−320.
9. Halpern, J; Kemp, A. L. W. The Decarbonylation of Formic Acid by Ruthenium(II) Chloride. J. Am.
Chem. Soc. 1966, 88, 5147–5150.
128
10. Grushin, V. V.; Kuznetsov, V. F.; Bensimon, C.; Alper, H. A Simple and Convenient Preparation of
[(Ph
3
P)
4
Rh
2
(µ-OH)
2
] and Its Reactions with C-H, O-H, and M-H Acids. Organometallics 1995, 14, 3927–
3932.
11. Anaby, A.; Feller, M.; Ben-David, Y.; Leitus, G.; Diskin-Posner, Y.; Shimon, L. J. W.; Milstein, D. Bottom-
Up Construction of a CO
2
‑Based Cycle for the Photocarbonylation of Benzene, Promoted by a
Rhodium(I) Pincer Complex. J. Am. Chem. Soc. 2016, 138, 9941−9950.
12. Ogo, S.; Nishida, H.; Hayashi, H.; Murata, Y.; Fukuzumi, S. Aqueous Transformation of a Metal
Diformate to a Metal Dihydride Carbonyl Complex Accompanied by H
2
Evolution from the Formato
Ligands. Organometallics, 2005, 24, 4816–4823.
129
Chapter 4. Catalyst Evolution in Ruthenium-Catalyzed Coupling of Amines and
Alcohols
4.1. Introduction
The chapter duplicates a manuscript that was published in ACS Catalysis in 2020 (Cherepakhin, V.;
Williams, T. J. Catalyst Evolution in Ruthenium-Catalyzed Coupling of Amines and Alcohols. ACS Catal.
2020, 10, 56–65).
Over the last decade many ruthenium-based catalytic systems have been developed that enable
alcohol-amine coupling through hydrogen borrowing. This reaction is of vital importance because of its
relevance to the efficient preparation of medicinal synthons. The known catalysts can be divided into
three structural groups. First, some catalysts are formed in situ from a metal precursor (such as
Ru
3
(CO)
12
,
1–5
[RuCl
2
(η
6
-p-cymene)]
2
,
6–13
[RuCl
2
(COD)]
n
,
14
RuCl
2
(PPh
3
)
3
,
7
[Cp*RuCl
2
]
2
,
15
or RuCl
3
·xH
2
O
16
) and
a phosphine. Second, some proceed from arene complexes, e.g. [(η
6
-arene)RuClL
2
]X
17–21
or [(η
6
-
arene)RuCl
2
L]
18,22
(L = PR
3
, NHC, Py, SR
2
, SeR
2
; X = Cl, PF
6
, OTf). Third, there are several excellent pincer
complexes of PNN,
23
PNO/PNS,
24
PNP,
25
and NNC
26
types (Figure 4.1) that typically contain RuH(CO)
fragments and operate through a metal-ligand cooperative mechanism that is enabled by deprotonation
of CH
2
PR
2
group. About half of the reported methods proceed from arene complexes (the second group),
but very little is known about the bonding and speciation of ruthenium in these catalyst systems. Although
some authors sketch intermediates and catalytic cycles for their systems,
10,15,18,19,22,24
most of these
proposals are not supported by experiment, and few address precatalyst speciation and activation, which
are almost certainly not simple when an (arene)ruthenium complex is introduced into a solution of amines
and alkoxides.
Understanding composition, structure, and reactivity of catalytic intermediates is crucial for
systematic comprehension and analysis of reaction mechanisms and the ways in which different ligands
130
govern catalytic activity, turnover, and deactivation of a homogeneous catalyst: it’s impossible to tell a
story until you know the characters. While such understanding ultimately can direct design of new, more
prolific catalytic systems, little detailed work on this problem for the arene-ligated ruthenium-based
amination catalysts was reported. Moreover, unexpected transformations of precatalytic species were
characterized, including ligand derivatization and displacement, ligation with substrate degradation
products, cluster formation, etc. with a number of ruthenium- and iridium-based precursors that were
expected to behave simply.
27
A recently reported ruthenium complex [(η
6
-cymene)RuCl(PyCH
2
PBu
t
2
)]OTf (4.1, Figure 4.1)
efficiently catalyzes coupling of primary amines and benzylic alcohols without the aid of a strong base.
21

In this study the reaction scope was extended to aliphatic alcohols and certain heterocyclic carbinols.
Identification of these conditions presaged a complicated story of why these had not been seen before.
To answer this, a study on the speciation and life cycle of the ruthenium complexes was conducted that
shows how precatalyst 4.1 activates, reacts, deactivates, and dies.
Figure 4.1. Precatalysts for alcohol-amine coupling.
4.2. Results and Discussion
4.2.1. Coupling of Aliphatic Amines and Alcohols
Complex 4.1 was developed as a catalyst for N-alkylation of primary amines with benzylic alcohols,
which left an opportunity to optimize the system for aliphatic alcohols. In the original study, 4.1
demonstrated excellent results with catalyst loadings down to 1 mol%. While benzyl alcohols react
smoothly with this catalyst loading, providing secondary amines with excellent yield and selectivity,
N
Ru
P
Cl
tBu
tBu
OTf
4.1
D. Milstein, 2015
N
N PPh
2
Ru
CO
H
Cl
T. Williams, 2017
131
aliphatic alcohols, tended to overalkylate and proceed in low efficiency, giving an undesirable yield and
selectivity of amine products. It is demonstrated here that cutting the catalyst load even further slows
down the overalkylation by aliphatic alcohol and enables selective, high yielding formation of secondary
amine products that were not achieved with the initial conditions.
The difference was demonstrated by using 1-aminohexane and 1-butanol as representative
substrates at 0.2 mol% Ru loading (Table 4.1). In the absence of alcohol (entry 1) 1-aminohexane
undergoes slow homocoupling to give dihexylamine and NH
3
. When 1-butanol is present, the
homocoupling route is halted and amine-alcohol coupling becomes the major reaction pathway (entries
2 – 4). The catalytic system exhibits high selectivity of amine monoalkylation by providing 98% yield of N-
butylhexylamine (entry 2). Increasing the alcohol/amine ratio above 1:1 does not significantly affect the
product distribution indicating slowness of the second alkylation step. Thus, the catalytic system is highly
selective for secondary amine formation. Possible by-products, such as amides, esters, carboxylates, and
imines are not detected. Imine formation is easily suppressed by conducting the reaction in a closed
reactor. Although the reaction is rapid (full conversion is reached within 1 hour with 1.0 mol% Ru), the
catalyst fails to give full conversion of 1-aminohexane at loadings below 0.05 mol% (vide infra).
Table 4.1. Coupling of 1-aminohexane with 1-butanol.
Entry Catalyst
[BuOH]/
[HexNH
2
]
HexNH
2
,
%
c
Hex
2
NH,
%
HexNHBu,
%
HexNBu
2
,
%
1
a
4.1 0 62 38 – –
2
a
4.1 1 0 0 98 2
3
a
4.1 2 0 0 93 7
4
a
4.1 3 0 0 93 7
5
b
4.1 1.5 0 0 87 13
6
b
[(Cymene)RuCl
2
]
2
, dppf (1 : 4) 1.5 100 0 0 0
OH 110
o
C
NH
2
H
N
N
H
N
[Ru]
132
7
b
Shvo complex 1.5 100 0 0 0
8
b
Ru
3
(CO)
12
, PPh
3
(1 : 6) 1.5 100 0 0 0
9
b
CpRuCl(PPh
3
)
2
1.5 85 0 15 0
10
b
RuH
2
(CO)(PPh
3
)
3
1.5 100 0 0 0
a
Reaction conditions: a mixture of 1-aminohexane (100 mg, 9.88 x 10
-4
mol), 1-butanol, and complex 4.1
(1.3 mg, 2.0 x 10
-6
mol, 0.2 mol%) was stirred in a closed reactor at 110
o
C for 36 h.
b
Reaction conditions: catalyst (1.98 x 10
-5
mol of Ru atoms, 1 mol%), 1-aminohexane (200 mg, 1.98 mmol),
and 1-butanol (220 mg, 2.97 mmol) were stirred in a closed reactor at 110
o
C for 1 hour.
c
The yields were calculated from
1
H NMR spectra.
The catalytic activity of complex 4.1 and the known alcohol-amine coupling catalysts, such as
[(cymene)RuCl
2
]
2
–dppf,
10,12,13
Shvo complex,
28
Ru
3
(CO)
12
–PPh
3
,
1,2,4,5,29
CpRuCl(PPh
3
)
2
,
30
and
RuH
2
(CO)(PPh
3
)
3
was compared (entries 5 – 10). Complexes 4.1 and CpRuCl(PPh
3
)
2
enable conversion of
1-aminohexane at 100% and 15%, respectively, while others show no catalytic activity ([BuOH]/[HexNH
2
]
= 1.5, 1.0 mol% Ru, 110
o
C, 1 h). Thus, 4.1 exhibits superior catalytic activity among the tested complexes
under the specified conditions.
The scope of alcohol-amine coupling with precatalyst 4.1 can be successfully extended to
heterocyclic substrates, such as pyridines, thiophenes, and indoles (Table 4.2). Acidic substrates, such as
phenols (entry 2), are tolerated as the system does not need a strong base to activate the catalyst.
Table 4.2. Expansion of substrate scope for amine-alcohol coupling.
a
Entry
Alcohol
Amine
Product
Catalyst, %
Time, h
Yield, %
1
b
0.2
36
90
2
0.4
42
70
R
2
OH
Complex 4.1
+ H
2
O
R
1
NH
2
110
o
C, Neat
N
H
R
2
R
1
+
OH
NH
2
NH
4a
HO
NH
2
BuOH
HO
NHBu
4b
133
3
0.4
30
83
4
0.4
30
81
5
c
0.7
42
62
6
b
0.2
20
74
a
Reaction conditions: a mixture of amine (2.0 mmol), alcohol (3.0 mmol), and
complex 4.1 was stirred for required period in a closed reactor at 110
o
C.
b
Alcohol loading is 2.0 mmol.
c
Alcohol loading is 1.3 mmol.
4.2.2. Time-Course Study. Synthesis and Characterization of Ruthenium Complexes
Discovery of improved catalyst performance at reduced catalyst loadings presaged a very interesting
story about dimerization, cluster formation, or some combination of multi-metallic pathways that could
be involved in the process, probably to the detriment of catalyst turnover. Despite its potential
complexity, the story was uncovered.
The investigation of catalyst speciation started with a time-course study using a stoichiometric
loading of precatalyst 4.1 with 1-butanol and 1-aminohexane as coupling partners. These starting
materials are particularly convenient for this purpose, since they allow a reaction at high temperature and
are easily separated from reaction mixture. This facilitates analysis and isolation of ruthenium
intermediates. In a typical experiment the molar ratio of [4.1]:[HexNH
2
]:[BuOH] was 1 : 6.5 : 144. The
reaction was performed in a closed reactor at 110
o
C, then the organic materials were removed under
vacuum and the residue was analyzed by
1
H and
31
P NMR spectroscopy (Figure 4.2).
MeO
NH
2
MeO
BuOH
MeO
NHBu
MeO
4c
N NH
2
BuOH
N NHBu
4d
S
OH
HexNH
2 4e
S
NHHex
N
H
NH
2
BuOH
N
H
NHBu
4f
134
Figure 4.2.
31
P{
1
H} NMR spectra of the crude reaction mixture demonstrating consecutive formation of
complexes 4.3 – 4.6. Species of unknown structure are marked with asterisks.
Initially, the reaction was terminated after three minutes. According to
31
P NMR, two major
ruthenium species in ca. 1 : 1 ratio are present in the system at this point: complex 4.1 (
31
P δ = 87.31 ppm)
and a new ruthenium compound (4.3) that gives a doublet at
31
P δ = 109.75 ppm (
2
J
PH
= 42.8 Hz). The
1
H
NMR spectrum contains the corresponding doublet at –8.65 ppm, which is characteristic of a metal
hydride ligand. Thus, complex 4.3 is a product of chloride replacement by hydride to give [(η
6
-
cymene)RuH(PyCH
2
PBu
t
2
)]OTf. Fractional crystallization failed to separate 4.3 from 4.1, therefore, its
identity was confirmed by independent synthesis from 4.1.
80 84 88 92 96 100 104 108 112 116 120 124 128 132 136 140
f1 (ppm)
3 min
10 min
30 min
1 hour
4 hours
4.4
4.4
4.4
4.5
4.5
4.6
4.1 4.3
*
* *
135
Scheme 4.1. Synthesis of intermediate 4.3.
Although [RuCl
2
(η
6
-cymene)]
2
converts to [(η
6
-cymene)RuH(PPh
3
)
2
]
+
when treated with AgPF
6
and
PPh
3
in methanol at 25
o
C,
31
treatment of 4.1 with AgOTf in the presence of alcohols gives high yield of
the corresponding triflate complex, [(η
6
-cymene)Ru(OTf)(PyCH
2
PBu
t
2
)]OTf (4.2), rather than the hydride
(Scheme 4.1). The
19
F NMR spectrum of 4.2 in CD
2
Cl
2
solution contains two distinct peaks at –78.66 and
–78.82 ppm with equal intensities, belonging to the coordinated and free triflate groups. Complex 4.2
reacts reversibly with 2-propanol to give hydride 4.3 (Scheme 4.1). Its formation is favored at 110
o
C in a
closed reactor; rapid removal of acetone under vacuum provided the product in 50% yield. At room
temperature the equilibrium is completely shifted to the left. It was shown by reacting 4.3 with HOTf in
acetone-d
6
to give rapid and selective formation of 4.2 as identified by its
31
P peak at 91.03 ppm. The
chemical shifts of the phosphine (
31
P δ = 109.75 ppm) and hydride (
1
H δ = –8.65 ppm) ligands are identical
for the compound obtained in this reaction and for the compound detected in the catalytic reaction after
three minutes. Thus, complex 4.3 is the first ruthenium intermediate in the sequence of precatalyst
speciation.
As the reaction proceeds among complex 4.1, 1-aminohexane, and 1-butanol, the color of the
reaction solution changes from orange-red to black-green within 30 minutes. If the reaction is stopped
N
Ru
P
Cl
tBu
tBu
OTf
AgOTf, CH
2
Cl
2
- AgCl
N
Ru
P
TfO
tBu
tBu
110
o
C
OTf
4.1 4.2 (92%)
4.3 (50%)
N
Ru
P
TfO
tBu
tBu
N
Ru
P
H
tBu
tBu
OTf OTf
OH
O
HOTf
+
+
4.2
136
after 1 hour, a black crystalline compound 4.4 is isolated with 63% yield (Scheme 4.2). The structure of
4.4 was established by single-crystal X-ray diffraction (Figure 4.3). The complex is a trinuclear cluster
formed by three Ru(II) atoms and arranged in an asymmetrical triangular fashion. The observed Ru–Ru
distances (2.717, 2.897, and 2.907 Å) are near Ru–Ru distances in Ru
3
(CO)
12
,
32
Ru
3
Cl
6
(PCy
3
)
3
,
33
and
ruthenium metal
34
(2.854, 2.593, and 2.649 Å, respectively), indicating significant intermetallic interaction
within Ru
3
core. These bonds are omitted from the structural diagram for clarity’s sake only. Complex 4.4
features ortho-metalated bridging pyridyl ligand coordinated to Ru–CO group. This carbonyl ligand
appears to derive from our starting alcohol, by analogy to an iridium-based alcohol oxidation system that
we have recently characterized.
27
While the ortho-metalated pyridyl fragment is a common substructure
in ruthenium carbonyl clusters,
35–37
typically derived from Ru
3
(CO)
12
, complex 4.4 is a unique example of
tandem selective monocarbonylation, pyridine ortho-metalation, and cluster self-assembly all happening
from a mononuclear precursor.
Scheme 4.2. Synthesis of intermediate 4.4.
Complex 4.4 was characterized by multinuclear NMR spectroscopy in CD
2
Cl
2
solution. In its
1
H
spectrum, 4.4 presents two hydride ligands with chemical shifts at –16.50 (ddd,
2
J
PH
= 51.6, 27.3, 9.1 Hz)
and –21.36 (dd,
2
J
PH
= 20.0, 4.5 Hz) ppm. These hydrides do not correlate in a COSY spectrum, meaning
that their peak multiplicities originate from
1
H–
31
P coupling. This feature was used to justify location and
coordination mode of the hydrides. Based on coupling pattern of the peaks at –16.50 and –21.36 ppm,
the coordination modes of the hydrides were attributed as µ
3
-H and µ-H, respectively. This assignment
Ru Ru
Ru
H Cl
N
Cl
PBu
t
2
CO
P
N
N P
H
OTf
N
Ru
P
Cl
tBu
tBu
OTf
110
o
C, 1 h
OH
NH
2
63%
4.1
4.4
137
fulfils coordinative saturation of all ruthenium atoms in the molecule.
31
P NMR data are consistent with
three inequivalent PN ligands (
31
P δ = 128.34, 116.38, and 89.76 ppm).

Figure 4.3. Molecular structures of the cations of 4.4 (left) and 4.6 (right) shown with 50% probability
ellipsoids. Hydrogen atoms and methyl groups are omitted for clarity.
Complex 4.1 is further derivatized when treated with an excess of 1-aminohexane (> 10 equivalents,
Scheme 4.3). After 24 hours, two major complexes, 4.5 and 4.6, were detected by their hydride peaks at
1
H δ = –15.34 and –21.03 ppm, respectively. Complexes 4.5 and 4.6 are formed in ca. 1:1 ratio, and they
persist even when 100 equivalents of 1-aminohexane is used (Figure 4.23). Chromatographic purification
followed by crystallization afforded 4.6 · CH
2
Cl
2
in 18% yield. Although we failed to obtain a pure sample
of 4.5 from this reaction mixture, it can be isolated as 4.5 · ½THF in 3% yield as a by-product in the
synthesis of complex 4.4.
Scheme 4.3. Synthesis of intermediates 4.5 and 4.6.
N
Ru
P
Cl
tBu
tBu
OTf
4.1
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O
O
OTf
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O
O
Cl
OH
NH
2
110
o
C, 24 h
4.5
4.6
138
The structure of dinuclear species 4.6 was established by single-crystal X-ray diffraction (Figure 4.3).
Surprisingly, apart from CO ligands derived from the alcohol, the complex contains a bridging butyrate
anion, itself the product of 1-butanol oxidation. NMR and MALDI-MS data on complexes 4.5 and 4.6
necessitate them to be diastereomers. Identical composition of the cations in 4.5 and 4.6 was deduced
from the mass spectra showing molecular ion peaks at m/z 857.01 and 857.21 Da, respectively. While 4.6
has a reflection plane and contains two chemically equivalent PN ligands, complex 4.5 has lower
symmetry, generating two sets of peaks for two different PN ligands in
1
H NMR spectrum. Based on this,
we formulate 4.5 and 4.6 as trans- and cis-isomers due to the arrangement of the PN ligands (Figure 4.4).
Consequently, their respective bridging hydride ligands have different coupling patterns in
1
H NMR
spectra: a doublet of doublets in 4.5 (
2
J
trans-PH
= 44.7 Hz and
2
J
cis-PH
= 12.5 Hz) and a triplet in 4.6 (
2
J
cis-PH
=
10.2 Hz).
Figure 4.4. Coupling patterns of the hydride ligands in
1
H NMR spectra of diastereomers 4.5 and 4.6.
4.2.3. Mechanism of Precatalyst Evolution and Death
A series of additional experiments were conducted to investigate reactivity of 4.3 – 4.6 and
determine the factors that govern their formation in the catalytic reaction. The results of these studies
can be formulated in the following 5 points.
4.6 (cis-, C
s
group)
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
4.5 (trans-, C
1
group)
139
1. Complex 4.4 preferentially forms at high ruthenium loading. Formation of 4.4 depends on the
[HexNH
2
]/[Ru] ratio in the reaction, and the complex is detected only when [HexNH
2
]/[Ru] < 40 (e.g., Ru
loading must be higher than 2.5 mol% for 4.4 to form). Under typical catalytic conditions, the catalyst
loading is below 1 mol%, so complex 4.4 is not readily formed.
2. Complex 4.4 forms from 4.1 and 4.3 through respectively dinuclear and trinuclear intermediates.
It appears that generation of trinuclear complex 4.4 from mononuclear species 4.1 and 4.3 proceeds
through the intermediacy of a dinuclear species. To look for a possible dinuclear intermediate, we
terminated the catalytic reaction ([4.1]:[HexNH
2
]:[BuOH] is 1 : 6.5 : 144) after 10 minutes. We find a
31
P
NMR spectrum from this experiment that contains peaks of 4.1, 4.3, and 4.4, in addition to three new
signals at 106.19, 105.65, and 104.57 ppm (Figure 4.2). The catalytic intermediates were
chromatographically separated and analyzed them by MALDI-MS. The major components were identified
as a dinuclear (785.22 Da) and a trinuclear (1193.76 Da) complexes, which undergo complete
transformation to 4.4 within 30 min (Figure 4.24). Unfortunately, it was impossible to obtain sufficient
data to establish the structures and stabilities of the new species, hereinafter referred to as complex 4.4
predecessors.
3. None of complexes 4.3 – 4.6 is the catalyst resting state. After preparing samples of 4.3 – 4.6, the
catalyst resting state had to be identified. For this purpose, the catalytic activity of 4.1 and 4.3 – 4.6 was
compared in the reaction between 1-aminohexane and alcohols (Table 4.3). As expected, pre-catalyst 4.1
gives full conversion of 1-aminohexane, as one would anticipate if the resting catalyst were added directly
to the reaction. None of the remaining complexes gives an analogous result: they all either suffer from
poor activity (complexes 4.3 and 4.4) or have no activity at all (complexes 4.5 and 4.6). Full conversion of
1-aminohexane is achieved when the mixture of complex 4.4 predecessors is used, indicating that one of
the components is (or can access) the catalyst resting state (entry 8). Thus, complex 4.4 was termed as a
dormant form of the catalyst, whereas inactivity of 4.5 and 4.6 makes them ultimate dead forms.
140
Table 4.3. Catalytic activity comparison test.
a
Entry [Ru] R HexNH
2
, %
b
HexNHR, % HexNR
2
, %
1 4.1 PhCH
2
0 > 99 0
2 4.1 Bu 0 52 48
3 4.3 PhCH
2
6 73 0
4 4.4 PhCH
2
55 28 0
5 4.4 Bu 32 68 0
6 4.5 Bu 100 0 0
7 4.6 Bu 100 0 0
8 see text Bu 0 85 15
a
Reaction conditions: a mixture of 1-aminohexane (51 mg, 0.5 mmol), alcohol (0.75
mmol) and Ru complex (5.00 x 10
-6
mol of Ru atoms) was stirred in a closed reactor
at 110
o
C for 18 h.
b
The yields were calculated from
1
H NMR spectra.
4. Complex 4.4 forms when primary amine is consumed, and the catalytic reaction is over. Whereas
it is formed at 110
o
C with a good yield, complex 4.4 should be quite stable under the catalytic conditions.
Indeed, it does not react with H
2
, CO, and/or CO
2
in CH
2
Cl
2
solution at 1 atm; no change is observed upon
its treatment with 1-butanol or 1-aminohexane independently at 110
o
C over 24 hours. When 4.4 is heated
with both 1-butanol and 1-aminohexane, however, it undergoes full conversion to a diversity of species
within 7 hours (Figure 4.23). Also,
1
H NMR analysis of organic materials formed in the catalytic reaction
shows absence of 1-aminohexane when complex 4.4 begins to form. This correlation shows limited
compatibility of 4.4 and the primary amine and renders 4.4 a kinetically stable product of post-catalytic
transformations.
5. Complex 4.4 reacts slowly with a secondary amine and water to form the ultimate dead species 4.5
and 4.6. Why does the catalyst die? Since complex 4.4 begins to form as soon as alcohol-amine coupling
is complete, the subsequent slow transformations of dormant catalyst 4.4 to the terminal (dead) forms
4.5 and 4.6 should be taking place in the medium of 1-(butylamino)hexane, water, and 1-butanol. Indeed,
[Ru] (1 mol%)
110
o
C, 18 h
NH
2
ROH
NHR
NR
2
141
when complex 4 reacts directly with 1-(butylamino)hexane, water, and 1-butanol (110
o
C, 20 h),
complexes 4.5 and 4.6 are formed, as shown by a
1
H NMR experiment (Figure 4.23). This process does not
affect product yields in alcohol-amine coupling when precatalyst loading is higher than 50 ppm. However,
catalyst deactivation becomes a problem at lower catalyst loading (below 50 ppm), where a smaller
portion of catalyst is available to be sacrificed to destructive interaction with reaction by-products.
In contrast to formation of complex 4.4, generation of 4.5 and 4.6 is independent of the system’s
[HexNH
2
]/[Ru] ratio. The bridging butyrate ligand in 4.5 and 4.6 emerges from ruthenium-catalyzed
acceptorless dehydrogenation of butanol to butyrate, which is well known.
38–46
Typically, the reaction
requires hydroxide as a source of oxygen (Scheme 4.4A), however, in the current catalytic system the
combination of water and secondary amine seems sufficient (Scheme 4.4B). 1-Butanol oxidation happens
stoichiometrically rather than catalytically, since no free butyrate was detected in the reaction mixture.
Scheme 4.4. Ruthenium-catalyzed alcohol oxidation.
Considering these points, a unified scheme for precatalyst activation, evolution, and death was
proposed (Scheme 4.5). The process begins with substitution of chloride for butoxide in precatalyst 4.1,
this requires equimolar amounts of 1-butanol and 1-aminohexane, where the amine is an HCl scavenger.
The resulting butoxide complex undergoes rapid β-hydride elimination to form butanal and hydride
complex 4.3. It was not observed directly, but its intermediacy is required for the formation of 4.3.
Following transformations of 4.3 include p-cymene dissociation, selective carbonylation of one of the
metals, and dimerization through ortho-metalation of a pyridine fragment. The resulting dinuclear species
4.7 of unknown structure could be the active catalyst, and a predecessor of complex 4.4. At high
ruthenium loading, when catalytic reaction is complete, unreacted 4.1 can trap the dinuclear active
R OH + OH
[Ru]
R O
O
+ 2H
2
R OH + H
2
O
R O
O
+ 2H
2
R
2
NH R
2
NH
2
+
A.
B.
heat
[Ru]
heat
142
catalyst 4.7 to form trinuclear dormant 4.4. The process is fast and selective due to high kinetic stability
of 4.4. Then, the system slowly reaches thermodynamic rest through a reaction among 4.4, 1-
(butylamino)hexane, water, and 1-butanol to form the dead catalyst forms 4.5 and 4.6.
Scheme 4.5. Precatalyst activation and death.
Discovery of the trinuclear ruthenium cluster 4.4 illustrates the high complexity of the inorganic side
of our catalytic story. It is a well-known phenomenon that ruthenium,
47,48
osmium,
48
and iridium
49,50
halide
complexes can consecutively dehydrogenate and decarbonylate primary alcohols in the presence of a
phosphine ligand, giving rise to M–CO fragment. This is the reason for carbonyl ligand being present in 4.4
– 4.6 and some other metal complexes, that are catalytically competent in alcohol dehydrogenation.
Scheme 4.6 demonstrates generation of such complexes and highlights their common fragment
(PN)MH(CO) (M = Ru
II
and Ir
III
). This structural analogy appears to be a consequence of the thermodynamic
stability of (PN)MH(CO) fragments, this allows them to form and be stable under catalytic reaction
N
Ru
P
Cl
tBu
tBu
N
Ru
P
H
tBu
tBu
N
Ru
P
O
tBu
tBu
H
CHO
BuOH
HexNH
2
HexNH
3
Cl
p-Cymene
Ru Ru
Ru
H Cl
N
Cl
PBu
2
CO
P
N
N P
H
N
Ru
P
Cl
tBu
tBu
Ru Ru
X L
N
X
PBu
2
CO
P
N
X
p-Cymene
HexNHBu
BuOH, H
2
O
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
4.5 4.6
+
4.1
4.3
4.4
4.1
FAST
SLOW
4.7
143
conditions (Scheme 4.6B and 4.6C).
27
It seems that selective monocarbonylation in all these cases is the
crucial step in precatalyst evolution to the active catalyst.
Scheme 4.6. Formation of structurally related catalytic complexes.
4.2.4. Electrochemistry
Triruthenium clusters are known to exhibit rich redox chemistry.
51–54
Therefore, electrochemical
properties of 4.4 were studied to evaluate the possibility of its single-electron transformations in the
catalyst lifecycle that would be invisible by NMR.
Redox properties of 4.4 (Ru
3
+
) were investigated by cyclic voltammetry in 0.1 M CH
2
Cl
2
solution of
[Bu
4
N]PF
6
at ambient temperature. Overall, four redox events were detected in the potential range of
–2.0 to 1.7 V vs. Fc
+
/Fc. Upon scanning cathodically, the first reduction occurs at E
1/2
= –0.784 V. This redox
event is electrochemically irreversible (ΔE
p
= 213 mV), and the back feature appears only at scan rates
higher than 400 mV/s. Applying more negative potential causes the second reduction event at E
p
= –1.776
V (at 100 mV/s). The corresponding back feature is not observed even at high scan rates. Thus, the
products of both reduction steps are unstable in the solution, making these events chemically irreversible.
Ru Ru
Ru
H Cl
N
Cl
PBu
t
2
CO
P
N
N P
H
Ir Ir
N
PBu
t
2
H
N
P
CO
H
H
Precatalyst for
alcohol-amine
coupling
(D. Milstein, 2015)
Catalyst
resting state
(Chapter 2)
Deactivated
catalyst
(this work)
Ru
Cl
CO
Ph
3
P
Ph
3
P
PPh
3
H
N
N
N
PPh
2
Ru
CO
H
Cl
Ir
P
N
tBu tBu
1-butanol, KOH
catalytic alcohol
oxidation
N
Ru
P
Cl
tBu
tBu
1
catalytic
alcohol-amine
coupling
1-butanol
1-aminohexane
4
PPh
2
A.
B.
C.
N
144
Applying positive potential, Ru
3
+
undergoes electrochemically reversible one electron oxidation to
Ru
3
2+
at E
1/2
= 0.442 V (ΔE
p
= 63 mV) (Figure 4.5). Variable scan rate study showed that Ru
3
2+
/Ru
3
+
couple
obeys the Randles−Sevcik equation and, therefore, Ru
3
2+
and Ru
3
+
are freely diffusing in the solution. The
second oxidation event occurs at E
p
= 1.481 V (at 100 mV/s), it is irreversible because of subsequent
chemical transformation. Electrochemical reversibility of the first oxidation step indicates possibility for
chemical oxidation of complex 4.4 using an oxidant with the formal potential higher than 0.442 V. For
example, oxidation with AgOTf (E
Ag+/Ag
= 0.65 V)
55
in CH
2
Cl
2
solution followed by crystallization from THF
gives [Ru
3
](OTf)
2
· THF (4.8 · THF) in 73% yield. Composition of the product was established by elemental
analysis. Effective magnetic moment (µ
eff
) of 4.8 was measured in CD
2
Cl
2
solution by Evans method
56,57

using a change of CH
2
Cl
2
chemical shift and found to be 1.88 BM. This value corresponds to one unpaired
electron in Ru
3
2+
and is slightly higher than the spin-only value (1.73 BM) for S = ½ state.
Based on high positive potential of Ru
3
2+
/Ru
3
+
couple, the generation of a persistent concentration
of a paramagnetic metal species is unlikely in the catalytic reaction. In sum, the observed electrochemical
potentials and magnetic moments, although interesting in their own right, are inconsistent with any
species that we observed in the catalytic pathway.
Figure 4.5. Cyclic voltammogram of 4.4 (1.0 mM) in CH
2
Cl
2
with 0.1 M [Bu
4
N]PF
6
at a scan rate of 50 mV/s.
145
4.3. Conclusions
The utility of complex 4.1 as a precatalyst for alcohol-amine coupling of aliphatic and some
heterocyclic carbinol substrates was demonstrated. Detailed analysis of the catalytic reaction between 1-
butanol and 1-aminohexane unraveled the precatalyst evolution sequence, that involves complexes 4.3 –
4.6. Complex 4.4 is a kinetically stable dormant catalyst form, whereas complexes 4.5 and 4.6 are the
ultimate dead catalyst forms. Selective formation of 4.4 is facilitated by a high ruthenium loading (> 2.5
mol% Ru) and forms via trapping a dinuclear active catalyst with unreacted precatalyst. Exhaustive catalyst
poisoning is caused by the reaction with secondary amine, alcohol, and water to give 4.5 and 4.6. The
inherence of MH(CO) fragment to alcohol dehydrogenation catalysts, that is generated from an alcohol
during precatalyst activation was pointed out for the first time.
4.4. Experimental Section
4.4.1. Materials and Methods
Complex 4.1 was synthesized according to published procedure.
21
CDCl
3
and CD
2
Cl
2
were purchased
from Cambridge Isotope Laboratories and were dried and distilled over CaH
2
. All alcohols and amines were
purchased from commercial sources and were dried and distilled over CaH
2
as well. Tyramine was
sublimed in vacuum. Hexane, CH
2
Cl
2
, Et
2
O, and THF were dried using a solvent purification system. HPLC
grade hexane and ethyl acetate (EDM Millipore) were used without purification for chromatographic
isolation of 4a – 4f on Teledyne CombiFlash instrument with “RediSep Rf Gold Amine” columns. All
reactions were conducted under nitrogen either in a Vacuum Atmospheres glovebox (0-5 ppm O
2
for all
manipulations) or outside the glovebox in a closed reactor.
1
H,
13
C,
19
F, and
31
P NMR spectra were acquired
on Varian Mercury 400, VNMRS-500, and VNMRS-600 spectrometers and processed using MestReNova
12.0.1. All chemical shifts are reported in ppm and referenced to the residual
1
H or
13
C solvent peaks.
146
Following abbreviations are used: (s) singlet, (bs s) broad singlet, (d) doublet, (t) triplet, (dd) doublet of
doublets, etc. NMR spectra of all metal complexes were taken in 8” J. Young tubes (Wilmad or Norell) with
Teflon valve plugs. GC-MS analyses were performed on Thermo Scientific Focus DSQ II instrument. MALDI-
MS spectra were acquired on Bruker Autoflex Speed MALDI Mass Spectrometer. Elemental analyses were
conducted on Flash 2000 CHNS Elemental Analyzer. Infrared spectra were recorded on Bruker OPUS FTIR
spectrometer. Electronic absorption spectra were acquired on Perkin-Elmer UV-NIR spectrometer. Cyclic
voltammetry experiments were carried out using a Pine potentiostat in a single compartment cell under
nitrogen.
4.4.2. General Procedure for Coupling of Amines and Alcohols
A mixture of primary amine (2.0 mmol), alcohol, and complex 4.1 (see Table 4.2) was stirred for
required period in a closed reactor at 110
o
C. Then, all volatile components were removed under vacuum,
and the product was purified by flash column chromatography (SiO
2
, hexane/ethyl acetate gradient).
1-(Butylamino)hexane (4a): Yellow oil (0.28 g, 90%).
1
H NMR (400 MHz, CDCl
3
): δ 2.58 (t, J = 7.3 Hz, 2H, CH
2
), 2.57 (t, J = 7.3 Hz, 2H, CH
2
), 1.52 – 1.40 (m,
4H, 2CH
2
), 1.38 – 1.21 (m, 8H, 4CH
2
), 1.04 (br s, 1H, NH), 0.94 – 0.84 (m, 6H, 2CH
3
).
13
C NMR (101 MHz, CDCl
3
): δ 50.34, 49.98, 32.49, 31.95, 30.33, 27.25, 22.76, 20.68, 14.18, 14.16.
IR (PE film, cm
-1
): 2927, 1467, 1131, 892.
GC-MS: m/z calcd. for [C
10
H
23
N]
+
157.18, found 157.15.
4-(2-(Butylamino)ethyl)phenol (4b): Colorless crystals (0.27 g, 70%).
1
H NMR (500 MHz, CDCl
3
): δ 7.03 (d, J = 8.2 Hz, 2H, ArH), 6.71 (d, J = 8.2 Hz, 2H, ArH), 4.26 (br s, 2H,
NH, OH), 2.88 (t, J = 6.8 Hz, 2H, CH
2
), 2.75 (t, J = 6.8 Hz, 2H, CH
2
), 2.64 (t, J = 7.4 Hz, 2H, CH
2
), 1.47 (p, J =
7.5 Hz, 2H, CH
2
), 1.29 (h, J = 7.0 Hz, 2H, CH
2
), 0.88 (t, J = 7.3 Hz, 3H, CH
3
).
13
C NMR (126 MHz, CDCl
3
): δ 155.55, 130.46, 129.86, 115.93, 50.98, 49.48, 34.91, 31.78, 20.59, 14.06.
147
IR (KBr, cm
-1
): 1618, 1598, 1520, 1465, 1379, 1255, 1109, 831.
MALDI-MS: m/z calcd. for [C
12
H
20
NO]
+
194.15, found 194.44.
N-(3,4-Dimethoxyphenethyl)butan-1-amine (4c): Yellow oil (0.39 g, 83%).
1
H NMR (600 MHz, CDCl
3
): δ 6.82 – 6.78 (m, 1H, ArH), 6.76 – 6.72 (m, 2H, ArH), 3.86 (s, 3H, OMe),
3.85 (s, 3H, OMe), 2.85 (t, J = 7.1 Hz, 2H, CH
2
), 2.75 (t, J = 7.1 Hz, 2H, CH
2
), 2.61 (t, J = 7.4 Hz, 2H, CH
2
), 1.44
(p, J = 7.2 Hz, 2H, CH
2
), 1.31 (h, J = 7.7 Hz, 2H, CH
2
), 0.89 (t, J = 7.4 Hz, 3H, CH
3
).
13
C NMR (151 MHz, CDCl
3
): δ 149.02, 147.53, 132.91, 120.66, 112.12, 111.45, 56.05, 55.94, 51.53,
49.81, 36.15, 32.41, 20.63, 14.14.
IR (PE film, cm
-1
): 1594, 1519, 1466, 1421, 1264, 1240, 1159, 1143, 1033, 809, 766.
MALDI-MS: m/z calcd. for [C
14
H
24
NO
2
]
+
238.18, found 238.64.
2-(2-(Butylamino)ethyl)pyridine (4d): Yellow oil (0.29 g, 81%).
1
H NMR (600 MHz, CDCl
3
): δ 8.50 (d, J = 4.8 Hz, 1H, ArH), 7.55 (td, J = 7.6, 1.8 Hz, 1H, ArH), 7.14 (d, J
= 7.8 Hz, 1H, ArH), 7.08 (ddd, J = 7.5, 4.9, 0.9 Hz, 1H, ArH), 3.01 – 2.92 (m, 4H, 2CH
2
), 2.60 (t, J = 7.3 Hz, 2H,
CH
2
), 1.43 (p, J = 7.3 Hz, 2H, CH
2
), 1.29 (h, J = 7.6 Hz, 3H, NH, CH
2
), 0.86 (t, J = 7.4 Hz, 3H, CH
3
).
13
C NMR (151 MHz, CDCl
3
): δ 160.52, 149.48, 136.40, 123.36, 121.28, 49.72, 49.62, 38.75, 32.38,
20.59, 14.10.
IR (PE film, cm
-1
): 1594, 1573, 1476, 1438, 1130, 751.
GC-MS: m/z calcd. for [C
11
H
18
N
2
]
+
178.15, found 178.10.
3-(2-(Hexylamino)ethyl)thiophene (4e): Colorless oil (0.17 g, 62%).
1
H NMR (500 MHz, CDCl
3
): δ 7.30 – 7.24 (m, 1H, ArH), 7.03 – 6.94 (m, 2H, ArH), 2.92 – 2.80 (m, 4H,
2CH
2
), 2.61 (t, J = 7.3 Hz, 2H, CH
2
), 1.46 (p, J = 7.0 Hz, 2H, CH
2
), 1.37 – 1.22 (m, 6H, 3CH
2
), 1.04 (br s, 1H,
NH), 0.88 (t, J = 6.6 Hz, 3H, CH
3
).
13
C NMR (126 MHz, CDCl
3
): δ 140.62, 128.31, 125.65, 120.99, 50.55, 50.07, 31.91, 30.99, 30.24, 27.18,
22.75, 14.18.
148
IR (PE film, cm
-1
): 1732, 1464, 1129, 774.
MALDI-MS: m/z calcd. for [C
12
H
22
NS]
+
212.15, found 212.51.
3-(2-(Butylamino)ethyl)indole (4f): Yellow solid (0.32 g, 74%).
1
H NMR (600 MHz, CDCl
3
): δ 8.66 (br s, 1H, NH), 7.60 (d, J = 7.9 Hz, 1H, ArH), 7.35 (d, J = 8.1 Hz, 1H,
ArH), 7.16 (t, J = 7.6 Hz, 1H, ArH), 7.08 (t, J = 7.5 Hz, 1H, ArH), 7.01 (s, 1H, ArH), 3.90 (br s, 1H, NH), 3.09 (t,
J = 7.2 Hz, 2H, CH
2
), 3.01 (t, J = 7.2 Hz, 2H, CH
2
), 2.69 (t, J = 7.8 Hz, 2H, CH
2
), 1.54 (p, J = 7.6 Hz, 2H, CH
2
),
1.28 (h, J = 7.4 Hz, 2H, CH
2
), 0.86 (t, J = 7.4 Hz, 3H, CH
3
).
13
C NMR (151 MHz, CDCl
3
): δ 136.55, 127.29, 122.59, 122.09, 119.39, 118.76, 112.48, 111.45, 49.21,
48.90, 30.67, 24.52, 20.41, 13.90.
IR (KBr, cm
-1
): 3289, 2729, 1626, 1456, 1358, 1237, 1107, 748.
MALDI-MS: m/z calcd. for [C
14
H
21
N
2
]
+
217.17, found 217.52.
149
Figure 4.6.
1
H and
13
C{
1
H} NMR spectra of 4a in CDCl
3
.
-0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
6.13
1.08
8.59
4.00
4.00
0.85
0.87
0.88
0.90
0.92
1.04
1.28
1.32
1.34
1.35
1.42
1.46
1.49
2.55
2.56
2.57
2.58
2.59
2.60
7.26 Chloroform
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.16
14.18
20.68
22.76
27.25
30.33
31.95
32.49
49.98
50.34
77.16 Chloroform
H
N
150
Figure 4.7.
1
H and
13
C{
1
H} NMR spectra of 4b in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
f1 (ppm)
2.93
2.15
1.97
2.02
2.05
2.00
1.90
1.86
1.85
0.86
0.88
0.89
1.25
1.27
1.28
1.30
1.31
1.44
1.46
1.47
1.49
1.50
2.62
2.64
2.65
2.74
2.75
2.77
2.87
2.88
2.90
4.26
6.70
6.72
7.02
7.04
7.26 Chloroform
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.06
20.59
31.78
34.91
49.48
50.98
77.16 Chloroform
115.93
129.86
130.46
155.55
HO
H
N
151
Figure 4.8.
1
H and
13
C{
1
H} NMR spectra of 4c in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0
f1 (ppm)
2.99
1.04
2.00
1.98
2.00
2.06
2.04
3.11
3.01
1.99
1.00
0.88
0.89
0.91
1.10
1.28
1.29
1.30
1.31
1.33
1.34
1.42
1.43
1.44
1.46
1.47
2.59
2.61
2.62
2.73
2.75
2.76
2.84
2.85
2.86
3.85
3.86
6.74
6.75
6.75
6.79
6.80
7.26 Chloroform
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.14
20.63
32.41
36.15
49.81
51.53
55.94
56.05
77.16 Chloroform
111.45
112.12
120.66
132.91
147.53
149.02
MeO
H
N
OMe
152
Figure 4.9.
1
H and
13
C{
1
H} NMR spectra of 4d in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5
f1 (ppm)
3.16
3.05
2.11
1.99
4.07
1.03
1.01
1.02
0.98
0.85
0.86
0.88
1.28
1.29
1.43
2.59
2.60
2.62
2.93
2.95
2.98
3.00
7.07
7.08
7.08
7.09
7.09
7.13
7.15
7.54
7.56
7.57
8.50
8.50
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.10
20.59
32.38
38.75
49.62
49.72
77.16 Chloroform
121.28
123.36
136.40
149.48
160.52
N N
H
153
Figure 4.10.
1
H and
13
C{
1
H} NMR spectra of 4e in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
3.60
0.94
6.93
2.24
2.19
4.01
1.88
1.17
0.86
0.88
0.89
1.28
1.30
1.31
1.43
1.45
1.46
1.47
2.59
2.61
2.62
2.82
2.83
2.84
2.86
2.87
2.89
6.95
6.96
6.99
7.25
7.26 Chloroform
7.26
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
14.18
22.75
27.18
30.24
30.99
31.91
50.07
50.55
77.16 Chloroform
120.99
125.65
128.31
140.62
S
H
N
154
Figure 4.11.
1
H and
13
C{
1
H} NMR spectra of 4f in CDCl
3
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5
f1 (ppm)
3.02
2.04
2.01
1.99
2.06
2.00
3.06
1.00
1.02
1.02
0.99
0.99
0.93
0.85
0.86
0.87
1.26
1.28
1.29
1.30
1.31
1.52
1.53
1.54
1.56
1.57
2.67
2.69
2.70
3.00
3.01
3.02
3.08
3.09
3.10
3.90
7.01
7.07
7.08
7.10
7.15
7.16
7.18
7.26 Chloroform
7.34
7.36
7.59
7.60
8.66
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160
f1 (ppm)
13.90
20.41
24.52
30.67
48.90
49.21
77.16 Chloroform
111.45
112.48
118.76
119.39
122.09
122.59
127.29
136.55
N
H
N
H
155
4.4.3. Synthesis of Ruthenium Complexes
[Ru(OTf)(η
6
-C
10
H
14
)(PyCH
2
PBu
t
2
)]OTf (4.2). Complex 4.1 (100 mg, 1.54 x 10
-4
mol) and AgOTf (39 mg,
1.54 x 10
-4
mol) were stirred in CH
2
Cl
2
(4 mL) for 1 hour at 25
o
C. Then, the solution was filtered and treated
with Et
2
O (10 mL) to induce crystallization of the product. Orange flakes were filtered, washed with Et
2
O,
and dried in vacuum (108 mg, 92%).
1
H NMR (500 MHz, CD
2
Cl
2
): δ 9.52 (d, J = 5.9 Hz, 1H, Py), 7.93 (t, J = 7.9 Hz, 1H, Py), 7.60 – 7.45 (m,
2H, Py), 6.70 (d, J = 6.4 Hz, 1H, C
6
H
4
), 6.65 (d, J = 5.5 Hz, 1H, C
6
H
4
), 6.48 (d, J = 6.4 Hz, 1H, C
6
H
4
), 5.84 (d, J
= 5.9 Hz, 1H, C
6
H
4
), 3.47 (dd, J = 16.9, 13.9 Hz, 1H, CH
2
), 3.13 (dd, J = 16.8, 7.9 Hz, 1H, CH
2
), 2.76 (hept, J =
7.0 Hz, 1H, Pr
i
), 2.13 (s, 3H, CH
3
), 1.51 (d, J = 14.6 Hz, 9H, Bu
t
), 1.34 (d, J = 6.8 Hz, 3H, Pr
i
), 1.31 – 1.23 (m,
12H, Pr
i
, Bu
t
).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 164.3 (d, J = 3.2 Hz), 158.5, 141.7, 125.5, 125.1 (d, J = 8.6 Hz), 106.3,
99.7, 93.7, 89.7, 87.6, 81.7, 38.9 (m), 32.2 (d, J = 21.1 Hz), 31.4, 30.2 (d, J = 2.6 Hz), 30.0 (d, J = 2.4 Hz),
23.9, 21.3, 18.6.
31
P{
1
H} NMR (202 MHz, CD
2
Cl
2
): δ 90.65.
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.66 (s, 3F, RuOTf), –78.82 (s, 3F, TfO
-
).
IR (KBr, cm
-1
): 2978, 1613, 1479, 1330, 1274, 1234, 1204, 1163, 1033, 1003, 640, 518.
MALDI-MS: m/z calcd for [C
25
H
38
F
3
NO
3
PRuS]
+
622.13, found 622.28.
Anal. calcd for C
26
H
38
F
6
NO
6
PRuS
2
: C 40.52, H 4.97, N 1.82. Found: C 40.43, H 5.21, N 1.80.
156
Figure 4.12.
31
P{
1
H} and
19
F NMR spectra of 4.2 in CD
2
Cl
2
.
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
90.67
-80.6 -80.4 -80.2 -80.0 -79.8 -79.6 -79.4 -79.2 -79.0 -78.8 -78.6 -78.4 -78.2 -78.0 -77.8 -77.6 -77.4 -77.2 -77.0 -76.8
f1 (ppm)
1.06
1.00
-78.82
-78.66
N
Ru
P
TfO
tBu
tBu
OTf
4.2
157
Figure 4.13.
1
H and
13
C{
1
H} NMR spectra of 4.2 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5
f1 (ppm)
12.05
3.31
9.13
3.08
1.03
1.03
1.10
1.00
1.03
1.03
1.01
2.03
1.01
1.02
1.25
1.27
1.28
1.33
1.34
1.50
1.53
2.13
2.72
2.73
2.74
2.76
2.77
2.79
2.80
3.11
3.13
3.14
3.16
3.44
3.47
3.48
3.50
5.32 Dichloromethane
5.84
5.85
6.47
6.49
6.64
6.65
6.69
6.71
7.51
7.52
7.54
7.55
7.92
7.93
7.95
9.51
9.52
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
18.55
21.31
23.89
30.00
30.02
30.16
30.18
31.38
32.14
32.31
38.76
38.89
38.92
39.05
53.84 Dichloromethane
81.73
87.59
89.71
93.66
99.68
106.26
125.07
125.14
125.46
141.67
158.51
164.30
164.33
N
Ru
P
TfO
tBu
tBu
OTf
4.2
158
[RuH(η
6
-C
10
H
14
)(PyCH
2
PBu
t
2
)]OTf (4.3). Complex 4.2 (100 mg, 1.30 x 10
-4
mol) and 2-propanol (4 mL)
were heated in a closed reactor at 110
o
C for 1 hour. Then, the solvent was removed in vacuum (oil bath,
60
o
C) to give a dark-yellow oil. Upon its crystallization from CH
2
Cl
2
–Et
2
O two fractions of crystals were
obtained: orange unreacted complex 4.2 and yellow product 4.3. The crystals were filtered, washed with
Et
2
O, and dried in vacuum (40 mg, 50%).
1
H NMR (600 MHz, CD
2
Cl
2
): δ 8.64 (d, J = 5.8 Hz, 1H, Py), 7.65 (t, J = 7.6 Hz, 1H, Py), 7.38 (d, J = 7.8 Hz,
1H, Py), 7.11 (t, J = 6.7 Hz, 1H, Py), 5.91 (d, J = 6.1 Hz, 1H, C
6
H
4
), 5.81 (d, J = 6.0 Hz, 1H, C
6
H
4
), 5.61 (d, J =
6.2 Hz, 1H, C
6
H
4
), 4.81 (d, J = 6.0 Hz, 1H, C
6
H
4
), 3.38 (dd, J = 16.9, 10.3 Hz, 1H, CH
2
), 3.09 (dd, J = 16.9, 7.7
Hz, 1H, CH
2
), 2.71 (hept, J = 6.8 Hz, 1H, Pr
i
), 2.34 (s, 3H, CH
3
), 1.34 (d, J = 7.0 Hz, 3H, Pr
i
), 1.33 (d, J = 7.0 Hz,
3H, Pr
i
), 1.29 (d, J = 14.0 Hz, 9H, Bu
t
), 1.25 (d, J = 13.2 Hz, 9H, Bu
t
), –8.65 (d,
2
J
PH
= 42.8 Hz, 1H, RuH).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 163.0 (d, J = 3.1 Hz), 157.6, 138.2, 124.0, 123.8 (d, J = 8.8 Hz), 117.8,
105.9, 95.4, 88.5, 87.9 (d, J = 6.5 Hz), 77.7, 38.2 (d, J = 10.7 Hz), 36.5 (d, J = 26.1 Hz), 35.7 (d, J = 24.8 Hz),
32.8, 30.3 (d, J = 3.1 Hz), 29.5 (d, J = 4.5 Hz), 24.7, 23.0, 19.7.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 109.75 (d, J = 11.8 Hz).
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.84.
IR (KBr, cm
-1
): 2976, 2023 (ν
RuH
), 1477, 1281, 1265, 1154, 1034, 639.
MALDI-MS: m/z calcd for [C
24
H
39
NPRu]
+
474.19, found 474.30.
Anal. calcd for C
25
H
39
F
3
NO
3
PRuS: C 48.22, H 6.31, N 2.25. Found: C 48.33, H 6.37, N 2.23.
159
Figure 4.14.
31
P{
1
H} and
19
F NMR spectra of 4.3 in CD
2
Cl
2
.
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
109.72
109.77
-200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20
f1 (ppm)
-78.84
N
Ru
P
H
tBu
tBu
OTf
4.3
160
Figure 4.15.
1
H and
13
C{
1
H} NMR spectra of 4.3 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
18.62
6.44
3.04
1.01
1.06
1.06
0.99
0.98
0.99
0.99
1.00
0.99
0.96
1.00
1.24
1.26
1.28
1.31
1.32
1.33
1.34
2.34
2.67
2.68
2.69
2.71
2.72
2.73
2.74
3.07
3.09
3.10
3.11
3.36
3.38
3.39
3.40
4.80
4.81
5.32 Dichloromethane
5.60
5.61
5.80
5.81
5.90
5.91
7.10
7.11
7.12
7.37
7.39
7.64
7.65
7.66
8.63
8.64
-8.9 -8.7 -8.5
1.00
-8.69
-8.62
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
19.69
23.03
24.65
29.50
29.53
30.29
30.31
32.77
35.62
35.79
36.37
36.54
38.17
38.24
53.84 Dichloromethane
77.69
87.90
87.94
88.48
95.43
105.86
117.75
123.72
123.78
123.95
138.19
157.64
163.00
163.02
N
Ru
P
H
tBu
tBu
OTf
4.3
161
[Ru
3
H
2
Cl
2
(CO)(PyCH
2
PBu
t
2
)
2
{µ-(C
5
H
3
N)CH
2
PBu
t
2
}]OTf (4.4). Complex 4.1 (2.00 g, 3.04 x 10
-3
mol),
1-butanol (42 mL, 0.459 mol), and 1-aminohexane (1.54 g, 1.52 x 10
-2
mol) were stirred under N
2
in a
closed reactor at 110
o
C for 1 hour. The orange suspension turned dark-green. All volatile components
were removed from the hot solution under vacuum. The evacuated reactor was transferred inside a
glovebox. The remains of organic materials were extracted by trituration with hexane and then with Et
2
O
to give dark-green precipitate. It was filtered and washed with Et
2
O. The material contains 4.4 and 4.5.
The solid was recrystallized twice from CH
2
Cl
2
–Et
2
O affording the product as black-green crystals (808 mg,
63%). Crystals suitable for X-ray analysis were obtained by slow evaporation of CH
2
Cl
2
–Et
2
O solution.
1
H NMR (600 MHz, CD
2
Cl
2
): δ 8.64 (d, J = 5.4 Hz, 1H, Py), 8.30 (d, J = 5.7 Hz, 1H, Py), 7.71 (d, J = 7.8
Hz, 1H, Py), 7.62 (t, J = 7.5 Hz, 1H, Py), 7.29 (t, J = 7.4 Hz, 1H, Py), 7.24 (d, J = 7.5 Hz, 1H, Py), 6.90 (t, J = 6.5
Hz, 1H, Py), 6.80 – 6.70 (m, 3H, C
5
H
3
N, Py), 6.11 (d, J = 7.7 Hz, 1H, C
5
H
3
N), 3.71 (dd, J = 16.7, 11.1 Hz, 1H,
CH
2
), 3.60 (dd, J = 17.3, 11.7 Hz, 1H, CH
2
), 3.48 – 3.29 (m, 3H, CH
2
), 3.07 (dd, J = 16.6, 7.9 Hz, 1H, CH
2
), 1.73
(d, J = 14.4 Hz, 9H, Bu
t
), 1.34 (d, J = 13.4 Hz, 9H, Bu
t
), 1.23 (d, J = 12.7 Hz, 9H, Bu
t
), 1.17 (d, J = 13.3 Hz, 9H,
Bu
t
), 0.96 (d, J = 13.5 Hz, 9H, Bu
t
), 0.90 (d, J = 12.4 Hz, 9H, Bu
t
), –16.50 (ddd,
2
J
PH
= 51.6, 27.3, 9.1 Hz, 1H,
RuH), –21.36 (dd,
2
J
PH
= 20.0, 4.5 Hz, 1H, RuH).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 205.9 (d, J = 12.1 Hz), 189.0, 168.2, 165.6, 164.1 (d, J = 5.4 Hz),
156.8, 154.6, 135.7, 133.8, 131.2, 130.1, 124.0 (d, J = 9.0 Hz), 122.3, 121.8 (d, J = 9.4 Hz), 121.6, 115.5 (d,
J = 8.8 Hz), 38.3 (d, J = 18.4 Hz), 38.1 (d, J = 19.9 Hz), 37.2 (d, J = 11.0 Hz), 36.7 (d, J = 22.0 Hz), 35.5 (d, J =
19.8 Hz), 34.7 (d, J = 14.5 Hz), 34.5 (d, J = 11.3 Hz), 30.8, 30.7, 29.8, 29.1, 28.6, 28.5.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 128.34, 116.38, 89.76.
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.89.
IR (KBr, cm
-1
): 2957, 2908, 2875, 1941 (ν
CO
), 1273, 1035, 639. UV-Vis (CH
2
Cl
2
; λ
max
, nm (ε, M
-1
cm
-1
)):
293 (15772), 420 (16409), 586 (4362). MALDI-MS: m/z calcd for [C
43
H
73
Cl
2
N
3
OP
3
Ru
3
]
+
1115.15, found
1114.71. Anal. calcd for C
44
H
73
Cl
2
F
3
N
3
O
4
P
3
Ru
3
S: C 41.80, H 5.82, N 3.32. Found: C 41.60, H 5.88, N 3.25.
162
Figure 4.16.
1
H and
13
C{
1
H} NMR spectra of 4.4 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
19.53
30.17
9.57
1.02
3.55
1.08
1.05
1.03
3.05
1.05
1.03
1.03
1.01
1.02
1.01
1.00
0.89
0.91
0.95
0.97
1.18
1.22
1.24
1.33
1.35
1.72
1.74
3.05
3.06
3.07
3.09
3.33
3.35
3.35
3.37
3.41
3.43
3.44
3.45
3.58
3.60
3.61
3.63
3.69
3.71
3.72
3.73
5.32 Dichloromethane
6.10
6.11
6.74
6.76
6.77
6.89
6.90
6.92
7.23
7.25
7.28
7.29
7.30
7.61
7.62
7.63
7.70
7.72
8.30
8.31
8.63
8.64
-16.8 -16.5 -16.2
1.00
-16.57
-16.56
-16.53
-16.51
-16.49
-16.47
-16.44
-16.42
-21.5 -21.3
1.01
-21.38
-21.37
-21.35
-21.34
-10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230
f1 (ppm)
28.50
28.64
29.05
29.79
30.69
30.77
34.49
34.57
34.64
37.15
37.22
38.01
38.14
38.19
38.31
53.84 Dichloromethane
115.44
115.50
121.58
121.74
121.80
122.26
123.92
123.98
130.06
131.23
133.75
135.67
154.64
156.77
164.07
164.10
165.64
168.23
188.97
205.89
205.97
Ru Ru
Ru
H Cl
N
Cl
PBu
t
2
CO P
N
N P
H
OTf
4.4
163
Figure 4.17.
31
P{
1
H} and
19
F NMR spectra of 4.4 in CD
2
Cl
2
.
Figure 4.18. Fragment of COSY NMR spectrum of 4.4 in CD
2
Cl
2
.
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
89.76
116.38
128.34
-200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20
f1 (ppm)
-78.89
Ru Ru
Ru
H Cl
N
Cl
PBu
t
2
CO P
N
N P
H
OTf
4.4
164
trans-[Ru
2
HCl(CO)
2
(PyCH
2
PBu
t
2
)
2
(µ-O
2
CPr
n
)]Cl (4.5). A brown-yellow CH
2
Cl
2
–Et
2
O solution, obtained
in the synthesis of 4.4, was evaporated to dryness and treated with THF. Concentration of the resulting
solution afforded yellow crystals of 4.5 · ½THF. They were filtered, washed with THF, and dried in vacuum.
Yellow crystalline powder (57 mg, 3%).
1
H NMR (600 MHz, CD
2
Cl
2
): δ 9.01 (d, J = 5.4 Hz, 1H, Py), 8.98 (d, J = 5.4 Hz, 1H, Py), 7.96 – 7.88 (m,
2H, Py), 7.88 – 7.80 (m, 2H, Py), 7.29 (t, J = 6.3 Hz, 1H, Py), 7.16 (t, J = 6.3 Hz, 1H, Py), 4.07 (dd, J = 16.7,
9.2 Hz, 1H, CH
2
), 3.93 (dd, J = 16.8, 10.2 Hz, 1H, CH
2
), 3.75 (dd, J = 16.6, 10.3 Hz, 1H, CH
2
), 3.69 (dd, J =
16.7, 9.9 Hz, 1H, CH
2
), 2.09 (dt, J = 14.1, 7.0 Hz, 1H, CH
2
CO
2
), 2.00 (dt, J = 15.8, 7.8 Hz, 1H, CH
2
CO
2
), 1.44
(d, J = 14.0 Hz, 9H, Bu
t
), 1.40 (d, J = 14.2 Hz, 9H, Bu
t
), 1.38 (d, J = 14.0 Hz, 9H, Bu
t
), 1.33 – 1.23 (m, 2H, CH
2
),
1.18 (d, J = 13.6 Hz, 9H, Bu
t
), 0.61 (t, J = 7.3 Hz, 3H, CH
3
), –15.34 (dd,
2
J
PH
= 44.7, 12.5 Hz, 1H, RuH).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 204.01 (d,
2
J
CP
= 12.9 Hz, CO), 203.69 (d,
2
J
CP
= 15.0 Hz, CO), 186.34
(CO
2
), 165.95 (d, J = 3.7 Hz), 163.45 (d, J = 1.6 Hz), 158.30, 155.46, 139.55, 139.42, 125.55 (d, J = 8.4 Hz),
124.78 (d, J = 8.4 Hz), 123.95, 123.47, 40.23, 37.92 (d, J = 22.4 Hz), 37.79 (d, J = 18.7 Hz), 37.62 (d, J = 14.1
Hz), 37.38 (d, J = 17.0 Hz), 36.45 (d, J = 20.9 Hz), 35.09 (d, J = 18.7 Hz), 30.07 (d, J = 2.6 Hz), 29.85 (d, J =
3.0 Hz), 29.50 (d, J = 2.7 Hz), 29.32 (d, J = 2.6 Hz), 19.31, 13.66.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 108.22, 93.26.
IR (KBr, cm
-1
): 2975, 2911, 2878, 1967 (ν
CO
), 1937 (ν
CO
), 1558 (ν
COO
), 1478, 1432.
MALDI-MS: m/z calcd for [C
34
H
56
ClN
2
O
4
P
2
Ru
2
]
+
857.15, found 857.01.
Anal. calcd for C
72
H
120
Cl
4
N
4
O
9
P
4
Ru
4
: C 46.60, H 6.52, N 3.02. Found: C 46.21, H 6.48, N 2.97.
Figure 4.19.
31
P{
1
H} NMR spectrum of 4.5 in CD
2
Cl
2
.
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
93.26
108.22
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
Cl
4.5
165
Figure 4.20.
1
H and
13
C{
1
H} NMR spectra of 4.5 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
3.00
9.37
2.79
27.85
1.02
1.16
2.24
1.00
1.00
1.01
1.03
2.04
2.01
2.03
0.62
1.17
1.20
1.28
1.37
1.39
1.39
1.42
1.43
1.45
2.02
2.08
3.69
3.76
3.93
4.08
5.32 Dichloromethane
7.17
7.29
7.84
7.90
7.95
8.99
9.02
-15.6 -15.4 -15.2
1.01
-15.38
-15.36
-15.31
-15.29
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210
f1 (ppm)
13.66
19.31
29.31
29.33
29.49
29.51
29.84
29.86
30.06
30.08
35.03
35.16
36.38
36.52
37.32
37.43
37.57
37.67
37.73
37.85
38.00
40.23
53.84 Dichloromethane
123.47
123.95
124.76
124.81
125.52
125.58
139.42
139.55
155.46
158.30
163.45
163.46
165.94
165.97
186.34
203.64
203.74
203.97
204.05
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O O
Cl
4.5
166
cis-[Ru
2
HCl(CO)
2
(PyCH
2
PBu
t
2
)
2
(µ-O
2
CPr
n
)]OTf (4.6). Complex 4.1 (200 mg, 3.04 x 10
-4
mol), 1-butanol
(4 mL, 0.044 mol), and 1-aminohexane (308 mg, 3.04 x 10
-3
mol) were stirred under N
2
in a closed reactor
at 110
o
C for 24 hours. The orange suspension turned brown. All volatile components were removed from
the hot solution under vacuum to give a brown paste containing 4.5 and 4.6. The following manipulations
were performed inside a glovebox. To enable crystallization of 4.6, organic and Ru-containing by-products
were separated by column chromatography on “RediSep Rf reversed-phase C18” silica dried in an oven at
120
o
C. The reaction mixture was dissolved in CH
2
Cl
2
, filtered, and dry loaded on the sorbent. A column (d
= 1.5 cm) was filled with the sorbent (10 mL) in Et
2
O and the dry loaded mixture. Elution with Et
2
O gave a
yellow band containing mostly organic by-products. Then, elution with Et
2
O–CH
2
Cl
2
(9 : 1) gave another
yellow band containing 4.5 and 4.6. The process was completed by washing the column with CH
2
Cl
2
that
gave the final portion of 4.5 and 4.6. At this point a green-colored band of 4.4 should remain on the
column. The Et
2
O–CH
2
Cl
2
and CH
2
Cl
2
solutions were combined and after a few days the product crystallized
as 4.6 · CH
2
Cl
2
. The orange crystals were separated, washed with Et
2
O, and dried in vacuum (30 mg, 18%).
Crystals suitable for X-ray analysis were obtained by slow evaporation of CH
2
Cl
2
–Et
2
O solution.
1
H NMR (600 MHz, CD
2
Cl
2
): δ 9.06 (d, J = 5.8 Hz, 2H, Py), 7.93 (t, J = 8.0 Hz, 2H, Py), 7.73 (d, J = 7.9 Hz,
2H, Py), 7.33 (t, J = 6.7 Hz, 2H, Py), 3.83 (dd, J = 16.8, 10.9 Hz, 2H, CH
2
), 3.57 (dd, J = 16.9, 8.5 Hz, 2H, CH
2
),
2.16 (t, J = 7.5 Hz, 2H, CH
2
), 1.48 (d, J = 14.2 Hz, 18H, 2Bu
t
), 1.39 (h, J = 7.4 Hz, 2H, CH
2
), 1.13 (d, J = 13.6
Hz, 18H, 2Bu
t
), 0.79 (t, J = 7.4 Hz, 3H, CH
3
), –21.07 (t,
2
J
PH
= 10.2 Hz, 1H, RuH).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 202.8 (d,
2
J
CP
= 17.3 Hz, CO), 186.6 (CO
2
), 163.3, 155.8, 139.4, 124.3
(d, J = 8.2 Hz), 124.2, 40.6, 38.1 (d, J = 14.6 Hz), 37.6 (d, J = 22.7 Hz), 37.3 (d, J = 22.2 Hz), 30.5 (d, J = 2.7
Hz), 29.4 (d, J = 2.6 Hz), 19.6, 13.8.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 104.65 (d, J = 9.0 Hz).
19
F NMR (564 MHz, CD
2
Cl
2
): δ –78.94. IR (KBr,
cm
-1
): 2974, 1975 (ν
CO
), 1944, 1559 (ν
COO
), 1283, 1262, 1027, 633. MALDI-MS: m/z calcd for
[C
34
H
56
ClN
2
O
4
P
2
Ru
2
]
+
857.15, found 857.21.
167
Figure 4.21.
1
H and
13
C{
1
H} NMR spectra of 4.6 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
3.01
19.61
2.60
18.39
2.00
2.02
2.00
2.02
2.03
1.97
1.89
0.77
0.79
0.80
1.12
1.14
1.37
1.38
1.39
1.41
1.46
1.49
2.15
2.16
2.17
3.55
3.56
3.58
3.59
3.80
3.82
3.83
3.85
5.32 Dichloromethane
7.32
7.33
7.34
7.73
7.74
7.91
7.93
7.94
9.05
9.06
-21.4 -21.1 -20.8
0.99
-21.09
-21.07
-21.05
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220
f1 (ppm)
13.81
19.64
29.39
29.41
30.47
30.49
37.26
37.41
37.54
37.69
38.07
38.16
40.57
53.84 Dichloromethane
124.21
124.26
124.32
139.42
155.83
163.28
186.57
202.77
202.89
37 38 39 40 41
37.26
37.41
37.54
37.69
38.07
38.16
40.57
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O
O
OTf
4.6
168
Figure 4.22.
31
P{
1
H} and
19
F NMR spectra of 4.6 in CD
2
Cl
2
.
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
104.63
104.67
-190 -180 -170 -160 -150 -140 -130 -120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20
f1 (ppm)
-78.94
N
Ru
P
CO
tBu
tBu
N
Ru
P
CO
tBu
tBu
Cl
H
O
O
OTf
4.6
169
[Ru
3
H
2
Cl
2
(CO)(PyCH
2
PBu
t
2
)
2
{(C
5
H
3
N)CH
2
PBu
t
2
}](OTf)
2
(4.8). Complex 4.4 (20 mg, 1.58 x 10
-5
mol) and
AgOTf (5 mg, 1.94 x 10
-5
mol) were stirred in CH
2
Cl
2
(4 mL) for 1 hour at 25
o
C. Dark-green solution turned
dark-blue, then it was filtered. The solvent was removed in vacuum giving a blue oil. It was dissolved in
THF (2 mL) and shortly after the product crystallized as 4.8 · THF. It was filtered, washed with THF, then
with hexane, and dried in vacuum. Black crystalline powder (16 mg, 73%).
IR (KBr, cm
-1
): 2961, 1971 (ν
CO
), 1820, 1479, 1436, 1277, 1157, 1034, 828, 639.
UV-Vis (CH
2
Cl
2
; λ
max
, nm (ε, M
-1
cm
-1
)): 305 (14043), 357 (9165), 605 (4465), 730 (3629).
MALDI-MS: m/z calcd for [C
43
H
73
Cl
2
N
3
OP
3
Ru
3
]
+
1115.15, found 1114.72.
Anal. calcd for C
49
H
81
Cl
2
F
6
N
3
O
8
P
3
Ru
3
S
2
: C 39.62, H 5.50, N 2.83. Found: C 39.99, H 5.54, N 2.77.
4.4.4. Formation of Complexes 4.5 and 4.6 Tracked by
1
H NMR Spectroscopy
Experiment 1. Complex 4.1 (1 eq.), 1-aminohexane (100 eq.), and 1-butanol (150 eq.) were stirred
in a closed reactor at 110
o
C (oil bath) for 24 h. Then, all volatile components were removed in vacuum
at 110
o
C (oil bath), the residue was dissolved in CD
2
Cl
2
and analyzed by
1
H NMR.
Experiment 2. Complex 4.1 (1 eq.), 1-aminohexane (50 eq.), and 1-butanol (150 eq.) were stirred in
a closed reactor at 110
o
C (oil bath) for 24 h. Then, all volatile components were removed in vacuum at
110
o
C (oil bath), the residue was dissolved in CD
2
Cl
2
and analyzed by
1
H NMR.
Experiment 3. Complex 4.1 (1 eq.), 1-aminohexane (10 eq.), and 1-butanol (150 eq.) were stirred in
a closed reactor at 110
o
C (oil bath) for 24 h. Then, all volatile components were removed in vacuum at
110
o
C (oil bath), the residue was dissolved in CD
2
Cl
2
and analyzed by
1
H NMR.
Experiment 4. Complex 4.4 (0.33 eq.), 1-(butylamino)hexane (20 eq.), water (20 eq.), and 1-butanol
(130 eq.) were stirred in a closed reactor at 110
o
C (oil bath). After 20 h the dark-green solution turned
dark-yellow, and all volatile components were removed in vacuum at 110
o
C (oil bath). The residue was
dissolved in CD
2
Cl
2
and analyzed by
1
H NMR.
170
Experiment 5. Complex 4.4 (0.33 eq.), 1-aminohexane (80 eq.), and 1-butanol (120 eq.) were stirred
in a closed reactor at 110
o
C (oil bath). After 7 h the dark-green solution turned orange, and all volatile
components were removed in vacuum at 110
o
C (oil bath). The residue was dissolved in CD
2
Cl
2
and
analyzed by
1
H NMR.
Figure 4.23.
1
H NMR spectra of crude reaction mixtures from experiments 1–5. Complexes 4.5 and 4.6
were detected in experiments 1–4 by their RuH peaks.
-23.5 -22.5 -21.5 -20.5 -19.5 -18.5 -17.5 -16.5 -15.5 -14.5 -13.5
f1 (ppm)
Exp. 1
Exp. 2
Exp. 3
Exp. 4
Exp. 5
4.5
4.6
171
4.4.5. Characterization of Complex 4.4 Predecessors
Figure 4.24. Top:
31
P{
1
H} NMR spectra of crude and chromatographically purified reaction mixture
terminated after 3 min. Bottom: MALDI-MS spectrum of the purified mixture showing molecular peaks of
dinuclear (785.22 Da) and trinuclear (1193.76 Da) complexes.
76 80 84 88 92 96 100 104 108 112 116 120 124 128 132 136
f1 (ppm)
104 105 106 107
104.53
104.60
104.69
105.71
106.19
106.33
300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500
m/z (Da)
1193.760
3.31%
1192.754
3.02%
1194.742
2.67%
1195.737
2.32%
1189.761
2.12%
785.222
1.97%
1188.793
1.79%
1196.751
1.53%
781.231
1.30%
1197.727
1.28% 1187.771
1.18%
787.218
1.01%
786.224
0.95%
1186.759
0.81%
1198.733
0.61%
779.234
0.56%
172
4.4.6. Electrochemical Study of Complex 4.4
Cyclic voltammetry experiments were carried out using a Pine potentiostat in a single compartment
cell under N
2
with a 3 mm diameter glassy carbon electrode as the working electrode, platinum wire
purchased from Alfa Aesar as the auxiliary electrode, and silver wire as the reference electrode. The CVs
were referenced to the ferrocenium/ferrocene couple at 0 V. The experiments were carried out in 0.1 M
[Bu
4
N]PF
6
dichloromethane solution.

Figure 4.25. Top left: cyclic voltammogram of 4.4 (1.0 mM) in CH
2
Cl
2
at a scan rate of 50 mV/s. The graph
demonstrates four waves at –1.776, –0.784, 0.442, and 1.481 V. Top right: cyclic voltammograms of 4.4
(1.0 mM) in CH
2
Cl
2
featuring a reversible wave at E
1/2
= 0.442 V at scan rates ranging from 25 mV/s to 2000
mV/s. Bottom: Randles-Sevcik plots for the wave at E
1/2
= 0.442 V.
173
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(Cl)
2
(P-i-Pr
3
)
2
(1). Syntheses and Crystal
Structure Determinations of trans-Ir(H)(Cl)
2
(CO)(P-i-Pr
3
)
2
(2), cis-Ir(H)(Cl)
2
(CO)(P-i-Pr
3
)
2
(4) and trans-
Ir(Cl)(CO)(P-i-Pr
3
)
2
(5). Inorganica Chim. Acta 1997, 258, 169–181.
50. Harris, P.; Madsen, R.; Olsen, E. P. K.; Singh, T.; Andersson, P. G. Experimental and Theoretical
Mechanistic Investigation of the Iridium-Catalyzed Dehydrogenative Decarbonylation of Primary
Alcohols. J. Am. Chem. Soc. 2014, 137, 834–842.
51. Nikolaou, S.; Toma, H. E. Synthesis, Spectroscopy and Electrochemistry of a μ-Oxo-Triruthenium
Cluster Containing a Bridged Bis(2,2′-Bipyridyl)Ruthenium(II) Moiety. Polyhedron 2001, 20, 253–259.
52. Dai, F. R.; Wu, Y. H.; Zhang, L. Y.; Li, B.; Shi, L. X.; Chen, Z. N. Spectroscopic, Electrochemical, and DFT
Studies of Oxo-Centered Triruthenium Cluster Complexes with a Bis(Tridentate) Triazine Ligand. Eur.
J. Inorg. Chem. 2011, 1, 2306–2316.
53. Cabeza, J. A.; Del Río, I.; Pérez-Carreño, E.; Pruneda, V. Reactivity of Cationic Triruthenium Carbonyl
Clusters: From Pyrimidinium Ligands to N-Heterocyclic Carbenes. Organometallics 2011, 30, 1148–
1156.
179
54. Zhang, H. X.; Sasaki, Y.; Abe, M.; Zhang, Y.; Ye, S.; Osawa, M. Preparation, Spectroscopy, and
Electrochemistry of Cyano-Bridged Bis(Oxo-Centered-Hexa(μ-Acetato)-Triruthenium) Complexes. J.
Organomet. Chem. 2015, 797, 29–36.
55. Connelly, N. G.; Geiger, W. E. Chemical Redox Agents for Organometallic Chemistry. Chem. Rev. 1996,
96, 877–910.
56. Evans, D. F. The Determination of the Paramagnetic Susceptibility of Substances in Solution by
Nuclear Magnetic Resonance. J. Chem. Soc. 1959, 2003–2005.
57. Deutsch, J. L.; Poling, S. M. The Determination of Paramagnetic Susceptibility by NMR: A Physical
Chemistry Experiment. J. Chem. Educ. 1969, 46, 167–168.
180
Chapter 5. Heterobimetallic Complexes of IrM (M = Fe
II
, Co
II
, and Ni
II
) Core and
Bridging 2-(Diphenylphosphino)pyridine: Electronic Structure and
Electrochemical Behavior
5.1. Introduction
The chapter duplicates a manuscript that was published in Dalton Transactions in 2020 (Cherepakhin,
V.; Hellman, A.; Lan, Z.; Sharada, S. M.; Williams, T. J. Heterobimetallic Complexes of IrM (M = Fe
II
, Co
II
,
and Ni
II
) Core and Bridging 2-(Diphenylphosphino)pyridine: Electronic Structure and Electrochemical
Behavior. Dalton Trans., 2020, 49, 10509-10515).
Homo- and heterodinuclear transition metal complexes are popular scaffolds for catalyst
development.
1– 3
Interest in such compounds is driven both by their complex electronic structures and
unique catalytic activities, both made possible by synergy of the multiple metal centers. Particularly,
activation of small molecules such as CO
2
, isonitriles, alkenes, and alkynes by bimetallic complexes is a
popular area in modern organometallic chemistry.
4,5
When in a chelate, 2-(diphenylphosphino)pyridine
(Ph
2
PPy) is a small-bite-angle ligand that, given the opportunity, prefers to serve as a bridge between two
different metal atoms, thus facilitating M–M’ bond formation. Homo- and heterodinuclear complexes
bearing two bridging Ph
2
PPy ligands are known since 1980,
6
and some iridium-containing complexes of
this type are known: IrCu, IrTl, IrPd, IrHg,
7
IrCd,
8
and IrIr.
9
This chapter reports the synthesis, spectroscopy, electrochemistry, and structural characterization
of new heterodinuclear complexes based on Ir–Fe, Ir–Co, and Ir–Ni cores and bridging Ph
2
PPy ligand. The
rationale for bringing together the atoms of first- and third-row transition elements is their fundamentally
different redox properties: combining one-electron processes available to the first row metals (e.g. Fe,
Co, and Ni) and two-electron transitions that were studied on iridium
9
can enable new types of metal
181
cluster catalysis.
10,11
Designing such reactivity begins with a detailed understanding of the synthesis and
electronic structure of these heterobimetallics.
5.2. Results and Discussion
5.2.1. Synthesis and Structure of the Metal Complexes
Dinuclear complexes 5.2–5.4 were obtained from the reactions of iridium precursor trans-
[IrCl(CO)(Ph
2
PPy)
2
] (5.1) and the corresponding dichlorometal etherate derivative, [Fe
4
Cl
8
(THF)
6
],
[Co
4
Cl
8
(THF)
6
], or [NiCl
2
(DME)] (DME = 1,2-dimethoxyethane), in dichloromethane at room temperature
(Scheme 5.1). Compounds 5.2–5.4 crystallize from a dichloromethane solution as disolvates of orange
(5.2), green (5.3), and red-pink (5.4) colors. The materials are soluble in dichloromethane and THF, but
insoluble in benzene, toluene, ether, and hexane.
Scheme 5.1. Syntheses of complexes 5.2 – 5.4.
From cursory inspection of known Ph
2
PPy-bridged Ir–M complexes, it appears that formation of the
Ir–M bond can be achieved in two ways, according to the oxidation potential of the M atom. When M has
low positive oxidation potential (Cu
I
, Tl
I
, Pb
II
,
12
Cd
II
), iridium-metal bond appears to result from a donor-
acceptor interaction between the filled 𝟓 𝒅 𝒛 𝟐 orbital on iridium and a corresponding empty orbital on M
atom. In this type of complex, iridium atom adopts a distorted square pyramidal geometry. When the
metal has a high positive oxidation potential (Pd
II
and Hg
II
), it facilitates the oxidative addition of an M–X
bond to iridium atom, resulting in Ir–M bond formation and the octahedral geometry of the Ir
III
atom. The
Ir
Ph
2
P
Ph
2
P
OC Cl
or NiCl
2
(DME)
N
N
Ir
Ph
2
P
Ph
2
P
OC
N
N
M
Cl
Cl Cl
Ir
Ph
2
P
Ph
2
P
OC
N
N
Co
Cl
Cl
Cl
Fe
4
Cl
8
(THF)
6
Co
4
Cl
8
(THF)
6
5.1
5.2 (M = Fe)
5.4 (M = Ni)
5.3
CH
2
Cl
2 CH
2
Cl
2
182
derivatives of Fe
II
, Co
II
, and Ni
II
conform to the former pattern, which was subsequently confirmed by X-
ray crystallography.
The structures of 5.2–5.4 were established by single-crystal X-ray diffraction (Figure 5.1). The
complexes possess dinuclear structure enabled by the bridging Ph
2
PPy ligand. Intermetallic distances in
5.2–5.4 (Ir1–Fe1 2.7659(7), Ir1–Co1 2.596(6), and Ir1–Ni1 2.7022(13) Å) are shorter than the sum of van
der Waals radii of iridium and the first-row metals which is 3.78 Å, indicating a significant intermetallic
interaction. Moreover, complex 5.3 exhibits the shortest Ir–M distance in the series indicating high
covalency of the Ir–Co bond. The overall metal-ligand arrangement is consistent with Ir
I
and M
II
interaction
where iridium atom acts as an L-type ligand for M
II
atoms. Complexes 5.2 and 5.4 are isomorphous with
the distorted octahedral coordination geometries of Fe
II
and Ni
II
atoms. The equatorial bond angles range
from 54 to 118
o
in these compounds: Cl1–Fe1–Cl2 117.70(3), Cl1–Fe1–Ir1 96.17(3), Cl2–Fe1–Cl3 93.56(2),
Cl3–Fe1–Ir1 52.574(19); Cl2–Ni1–Cl3 110.89(6), Cl2–Ni1–Ir1 101.12(5), Cl3–Ni1–Cl1 93.79(5), and Cl1–
Ni1–Ir1 54.21(3). The Ir–M bonds in these compounds are stabilized by the bridging chloride ligands.

Figure 5.1. Molecular structures of 5.2, 5.3, and 5.4 shown with 50% probability ellipsoids. Hydrogen
atoms and dichloromethane molecules are omitted for clarity. Selected bond distances (Å): (5.2) Ir1–Fe1
2.7659(7), (5.3) Ir1–Co1 2.596(6), and (5.4) Ir1–Ni1 2.7022(13).
Surprisingly, the structure of complex 5.3 deviates from 5.2 and 5.4: the torsion angle P1–Ir1–Co1–
N1 is significantly larger compared to the other analogs (28.30 vs. 1.62 (5.2) and 1.49
o
(5.4)), resulting in
5.2
5.3 5.4
183
the absence of the bridging chloride ligand, and enabling a distorted trigonal bipyramidal geometry of Co
II

atom with the equatorial bond angles ranging from 113 to 125
o
: Cl3–Co1–Ir1 124.79(14), Cl2–Co1–Ir1
122.58(16), and Cl2–Co1–Cl3 112.63(19)
o
. The absence of bridging chloride in complex 5.3 is also
confirmed by geometry relaxation calculations carried out using density functional theory.
Complex 5.4 represents a rare example of Ir–Ni bond, the other cases are limited to [IrNi
8
(CO)
18
]
3–

(2.015 – 3.047 Å)
13
and [(Cp*IrS)
4
Ni]
2+/+
(2.596 – 2.699 Å).
14
5.2.2. Spectroscopic Studies
Complexes 5.2–5.4 were studied by
1
H NMR spectroscopy. The proton spectra exhibit broad peaks
consistent with the presence of paramagnetic Fe
II
, Co
II
, and Ni
II
atoms. Effective magnetic moments (µ
eff
)
of 5.2–5.4 were measured by Evans method using CH
2
Cl
2
peaks in
1
H NMR spectra (Table 5.1).
15
Complex
5.4 has µ
eff
= 2.86 BM, which agrees with the spin-only magnetic moment value (µ
so
= 2.83 BM) for an
octahedral high-spin ion with d
8
-configuration (
3
A
2
ground state of Ni
II
). Effective magnetic moments of
5.2 and 5.3, however, deviate from the expected spin-only values: µ
eff
(5.2) = 5.04 BM (µ
so
= 4.90 BM) and
µ
eff
(5.3) = 5.04 BM (µ
so
= 3.87 BM). This deviation was attributed to significant orbital contribution to the
magnetic moments, which is expected for
5
T
2
and
4
T
1
ground states of Fe
II
and Co
II
respectively. Thus, in
all the complexes the first-row metal atoms exist in their high-spin configurations, and the Ir–M
interaction does not cause high-spin to low-spin transition at room temperature in a dichloromethane
solution.
Table 5.1. Summarized spectroscopic data.
Compound ν(CO), cm
-1
µ
eff
, BM λ
max
, nm
5.1 1959 0 340, 387, 440
5.2 2008 5.04 343, 438
5.3 2012 5.04 330,
a
361,
a
442
5.4 2010 2.86 330,
a
374, 513
a
Shoulder
184
IR spectroscopy demonstrates that ν(CO) vibration is sensitive to the presence of Ir–M bond in 5.2–
5.4. The corresponding absorption band in the dinuclear complexes appears at 2008 – 2012 cm
-1
, whereas
5.1 has the band at 1959 cm
-1
. The observation indicates that Ir–M interaction reduces electron density
on the iridium atom and, consequently, decreases back donation to the CO ligand. This effect was
detected previously in iridium and iron heterodinuclear complexes: [IrI(CO)
2
(µ-Ph
2
PPy)
2
CdI
2
] (2002, 2066
cm
-1
),
8
[IrCl(CO)(µ-Ph
2
PPy)
2
Cu]BF
4
(1983 cm
-1
), [IrCl(CO)(µ-Ph
2
PPy)
2
Tl]PF
6
(1994 cm
-1
),
7
and [(OC)
3
Fe(µ-
Ph
2
PPy)ML
n
].
16
Complexes 5.2–5.4 were investigated by electronic absorption spectroscopy in dichloromethane
solution at room temperature (Figure 5.2). According to Kuang et al.,
8
complex 5.1 has absorption bands
at 338, 386, and 440 nm, that is the three-band pattern typical for Vaska-type complexes.
17
Installation of
the second metal atom seems to have a minor effect on the number and intensity of the absorption bands
in the resulting spectrum. Thus, the spectra of 5.1–5.4 are quite similar having one or two strong bands
with λ
max
< 400 nm (ε = 3700 – 5200 M
-1
cm
-1
) and a weak band with λ
max
> 400 nm (ε = 400 – 1400 M
-1
cm
-1
). An analogous picture is observed in the case of [IrX(CO)(µ-PN)
2
ML
n
] (X = Cl – I, M = Na, K, Tl, Sn,
Pb).
12,18
The lowest energy band of complex 5.4 demonstrates a significant bathochromic shift (513 nm)
compared to the same band of 5.1–5.3 (437 – 442 nm).
Figure 5.2. Electronic absorption spectra of 5.1 – 5.4 in CH
2
Cl
2
at 25
o
C.
185
5.2.3. Computational studies
Although the electronic absorption spectra of Vaska-type complexes and the complexes with Ir–M
bonds had been discussed before, the assignment of the bands made by different authors is contradictory.
Therefore, a computational study was performed to assign the high-energy bands at 330 – 340 nm using
time-dependent density functional theory.
19
Complexes 5.1 – 5.4 happened to be challenging systems for
theoretical analysis because of high sensitivity of peak locations to the choice of effective core potentials
for transition metal atoms. Caution is advised with interpretation of computational UV-Vis spectra, for
this reason the theoretical analysis was restricted to characterizing the origins of transitions reflected in
the UV-Vis spectra using natural transition orbitals (NTOs).
20
Table 5.2. The dominant natural transition orbital pairs for the excited states corresponding to the largest
oscillator strength for 5.1 – 5.4.
Compound Hole → Particle(1) Hole → Particle(2)
5.1

5.2

5.3

State 13: Excitation energy = 4.20 eV State 4: Excitation energy = 3.62 eV
State 8-β: Excitation energy = 3.76 eV State 8-α: Excitation energy = 3.76 eV
State 12-β: Excitation energy = 3.99 eV State 12-α: Excitation energy = 3.99 eV
186
5.4
Table 5.2 illustrates selected NTO hole-particle pairs related to the two largest excitation amplitudes
in complexes 5.1–5.4, and Table 5.3 shows the assignment of the corresponding experimental absorption
bands. In complex 5.1, the observed bands at 340 and 440 nm (E
calc
= 3.62 and 2.79 eV, respectively) are
assigned to the apparent metal-to-ligand charge transfer (MLCT) from occupied 𝟓 𝒅 𝒛 𝟐 orbital of the iridium
center to an empty π* orbital of the carbonyl ligand. The third NTO pair originates from MLCT between
the filled d
xz
/d
yz
orbital of iridium atom and an antibonding orbital which is delocalized among all four
coordinating atoms (E
calc
= 4.20 eV, 295 nm). This latter transition seems to appear near the absorption
edge of the solution.
Table 5.3. Assignment of the experimental UV-Vis absorption bands.
Compound
λ
max
,
nm
E (exp.),
eV
E (calc.),
eV
Assignment
5.1
340
387
440
3.65
3.20
2.82
4.20
3.62
2.79
MLCT
MLCT
MLCT
5.2
343
438
3.62
2.83
3.76
2.83
MLCT (α), IC (β)
MLCT (α), IC (β)
5.3
330
361
442
3.76
3.43
2.81
3.99
3.40
3.11
MLCT (α), IC (β)
LMCT (α, β)
MLCT (α), IC (β)
5.4
330
374
513
3.76
3.32
2.42
3.63
3.31
2.42
MLCT (α), IC (β)
LMCT (α, β)
IC (β)
Analysis of alpha spin-orbitals demonstrates that the NTO pairs in the series 5.2–5.4 are very similar
in shape and correspond to the MLCT from 𝟓 𝒅 𝒛 𝟐 orbital of iridium atom to the carbonyl ligand, the same
State 10-α: Excitation energy = 3.63 eV State 10-β: Excitation energy = 3.63 eV
187
as in complex 5.1 (Table 5.2, right column). While the orbitals of iron and nickel do not contribute
significantly to the ground states in this series of NTOs, the orbitals of cobalt do, which could be the reason
for the deviating crystal structure of 5.3 and the shortest distance Ir–Co in the series.
Although NTOs derived from beta spin-orbitals of compounds 5.2–5.4 have a complex shape, these
were described as intra-cluster (IC) transitions, since the electron density of the ground and exited states
is delocalized between both metal atoms in Ir–M cluster (Table 5.2, left column). Moreover, complex 5.4
exhibits significant contribution of p-orbitals of terminal chloride ligands to the ground state, which is not
observed in 5.1–5.3 (state 10-β).
To sum up, the computational data suggest that the observed UV-Vis absorption bands result from
the electronic transitions from molecular orbitals with a high contribution of 𝟓 𝒅 𝒛 𝟐 orbital of iridium atom.
The transitions can be described as a combination of IC and MLCTs.
5.2.4. Electrochemical studies
Electrochemical properties of compounds 5.2–5.4 were assessed by cyclic voltammetry in 0.1 M
solution of [Bu
4
N][PF
6
] in dichloromethane and tetrahydrofuran at room temperature under nitrogen
atmosphere. None of the complexes showed an electrochemically reversible redox event upon either
oxidation or reduction. Moreover, in most cases the products of electrochemical reactions deposited on
the electrode surface, except for reduction of complex 5.4 and oxidation of complex 5.3.
Upon scanning cathodically in dichloromethane, complex 5.4 undergoes reduction at E
p
= –1.49 V
(25 mV/s, vs. Fc
+/0
). At slow scan rates (25 and 50 mV/s), the reduction event is chemically irreversible,
with no return oxidation wave (Figure 5.3). As the scan rate is increased, the return oxidation wave
appears at –0.88 V (1000 mV/s, ΔE
p
= 740 mV, vs. Fc
+/0
). suggesting an ECE mechanism for the
transformation of 5.4.
21
The increase of the scan rate also causes higher peak currents for both the anodic
and cathodic waves along with the wave shift to more positive and negative potentials, respectively.
188
Plotting log(peak current) vs. log(scan rate) yields a linear relationship with a slope of approximately 0.5,
indicating that redox couples involved in the ECE mechanism obey the Randles−Sevcik equation, and that
freely diffusing molecular species are contributing to the observed electrochemical event rather than
species adsorbed on the electrode surface (Figure 5.4). Additionally, plotting peak current vs. the square
root of the scan rate yields a linear relationship, which is also consistent with freely diffusing complex 5.4
and its reduced forms (Figure 5.5).
Figure 5.3. Cyclic voltammograms of 1 mM 5.4 in CH
2
Cl
2
with 0.1 M [Bu
4
N][PF
6
] at various scan rates.
Figure 5.4. Plot of log(current density) versus log(scan rate) for complex 5.4.
189
Figure 5.5. Plot of peak current versus the square root of the scan rate for complex 5.4.
Figure 5.6. Cyclic voltammograms of 1 mM 5.3 in THF with 0.1 M [Bu
4
N][PF
6
] at various scan rates.
Applying positive potential in tetrahydrofuran, complex 5.3 undergoes two chemically irreversible
oxidation events at E
p
= 0.43 and 1.05 V (at 25 mV/s) without any sign of return reduction (Figure 5.6).
Increasing the scan rate up to 2000 mV/s does not result in the appearance of the return reduction waves,
which is the evidence for a fast chemical reaction that follows the oxidation steps.
Overall, the absence of well-behaved electrochemically reversible redox couples involving complexes
5.2–5.4 indicates high reactivity of their reduced and oxidized forms that are not stable under the
experiment conditions.
190
5.3. Conclusions
Three complexes based on an Ir–M (M = Fe
II
, Co
II
, and Ni
II
) heterobimetallic core and 2-
(diphenylphosphino)pyridine (Ph
2
PPy) ligand were synthesized via the reaction of trans-
[IrCl(CO)(Ph
2
PPy)
2
] and the corresponding metal chloride. Their structures were established by single-
crystal X-ray diffraction as [Ir(CO)(µ-Cl)(µ-Ph
2
PPy)
2
FeCl
2
]·2CH
2
Cl
2
(5.2), [IrCl(CO)(µ-Ph
2
PPy)
2
CoCl
2
]·2CH
2
Cl
2

(5.3), and [Ir(CO)(µ-Cl)(µ-Ph
2
PPy)
2
NiCl
2
]·2CH
2
Cl
2
(5.4). The electronic structure of these compounds was
studied by spectroscopic (NMR, IR, and UV-Vis) and computational (time-dependent DFT) methods to get
an insight to the nature of iridium-metal bonding. Magnetic moment measurements show that the
common high-spin electronic states of Fe
II
, Co
II
, and Ni
II
atoms are not affected by the coordination with
Ir
I
. Time-dependent DFT computations suggest that the observed absorption bands result from the
electronic transitions from molecular orbitals that have a dominant contribution of 5𝑑
𝑧 2
orbital of iridium
atom. Electrochemical studies showed that the oxidized and reduced forms of 5.2–5.4 are highly reactive
and decompose under the experiment conditions, which demonstrates poor ability of Ir
I
to stabilize the
first-row transition metals in their potential application in electrocatalysis. While these complexes are not
stable to electrocatalysis conditions, the data presented here refine our understanding of the bonding
synergies of the first-row and third-row metals.
5.4. Experimental Section
5.4.1. Materials and Methods
[Fe
4
Cl
8
(THF)
6
] and [Co
4
Cl
8
(THF)
6
] were synthesized according to the described procedures.
22,23

[NiCl
2
(DME)], [Ir
2
Cl
2
(COD)
2
], 2-(Diphenylphosphino)pyridine, and carbon monoxide were purchased
from commercial sources and used without further purification. Dichloromethane, diethyl ether, and
hexane were dried according to standard methods. Dichloromethane-d
2
was purchased from Cambridge
Isotopes Laboratories and dried over CaH
2
followed by distillation. All the synthetic procedures were
191
carried out in a Vacuum Atmosphere glove box under nitrogen (1 – 10 ppm O
2
).
1
H,
13
C, and
31
P NMR
spectra were recorded on Varian VNMRS 500 and 600 spectrometers, and processed using MestReNova
v11.0.2. All chemical shifts are reported in ppm and referenced to the residual
1
H or
13
C solvent peaks.
NMR spectra of air-sensitive compounds were taken in 8” J. Young tubes (Wilmad or Norell) with Teflon
valve plugs. Infrared spectra were recorded on Bruker OPUS FTIR spectrometer. MALDI-MS spectra were
acquired on Bruker Autoflex Speed MALDI Mass Spectrometer.
Elemental analyses were conducted on Flash 2000 CHNS Elemental Analyzer. UV-Vis spectra were
recorded on Perkin-Elmer UV/Vis/NIR spectrophotometer.
Electrochemistry experiments were carried out using a Pine potentiostat. The experiments were
performed in a single compartment electrochemical cell under nitrogen atmosphere using a 3 mm
diameter glassy carbon electrode as the working electrode, a platinum wire as auxiliary electrode and a
silver wire as the reference electrode. All experiments were referenced relative to ferrocene (Fc) with the
Fc
+/0
couple at 0.0 V using decamethylferrocene as an internal standard. All experiments were performed
with 0.1 M tetrabutylammonium hexafluorophosphate as a supporting electrolyte.
All simulations are carried out using the ab initio quantum chemistry software, Q-Chem 5.1.2.
25

Geometry optimizations and excited state calculations are carried out using the CAM-B3LYP functional
26

along with the LANL08
27
effective core potential (ECP) for Ir, Ni, Fe, and Co, the 6-311G* basis set for N,
P, and Cl, and 6-31G* basis set for H, C, and O atoms. The choice of level of theory is guided by previous
work with Pt complexes by Roy and coworkers.
28
NTOs are visualized using Jmol.
29
5.4.2. Synthetic Procedures and Characterization Data
trans-[IrCl(CO)(Ph
2
PPy)
2
] (5.1): This compound was synthesized from [Ir
2
Cl
2
(COD)
2
], Ph
2
PPy, and
CO in CH
2
Cl
2
according to the described procedure.
7,8,24

192
1
H NMR (600 MHz, CD
2
Cl
2
): δ 8.75 (ddd, J = 4.7, 1.8, 1.0 Hz, 1H), 8.03 (d, J = 7.8 Hz, 1H), 7.90 – 7.80
(m, 4H), 7.73 (td, J = 7.7, 1.7 Hz, 1H), 7.49 – 7.39 (m, 6H), 7.30 (ddd, J = 7.7, 4.7, 1.1 Hz, 1H).
13
C{
1
H} NMR (151 MHz, CD
2
Cl
2
): δ 171.17, 157.63 (t, J = 36.9 Hz), 150.40, 135.86, 135.61, 132.40 (t, J
= 27.2 Hz), 131.92 (t, J = 11.8 Hz), 130.87, 128.40, 124.52.
31
P{
1
H} NMR (243 MHz, CD
2
Cl
2
): δ 24.37.
IR (KBr, cm
-1
): ν(CO) 1959.
MALDI-MS: m/z [M – CO]
+
calcd. 754.10, found 753.96; [M – COCl]
+
calcd. 719.14, found 718.97.
Figure 5.7.
1
H and
13
C{
1
H} NMR spectra of 5.1 in CD
2
Cl
2
.
3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
1.12
6.16
1.12
4.04
1.00
0.91
5.32 Dichloromethane
7.29
7.29
7.30
7.30
7.30
7.30
7.31
7.31
7.41
7.42
7.43
7.44
7.45
7.46
7.47
7.72
7.72
7.73
7.73
7.74
7.74
7.86
8.02
8.03
8.74
8.74
8.74
8.74
8.75
8.75
8.75
8.75
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180
f1 (ppm)
53.84 CD2Cl2
124.52
128.40
130.87
131.92
132.40
135.61
135.86
150.40
157.63
171.17
Ir
Ph
2
P
Ph
2
P
OC
N
N
Cl
5.1
193
Figure 5.8.
31
P{
1
H} NMR spectrum of 5.1 in CD
2
Cl
2
.
General procedure for the synthesis of 5.2 and 5.3: In a glovebox, 5.1 (20 mg, 2.56 x 10
-5
mol) and
[M
4
Cl
8
(THF)
6
] (6 mg, 6.39 x 10
-6
mol) were mixed with dry CH
2
Cl
2
(5 mL) and stirred at room
temperature for 5 h. The resulting solution was filtered and concentrated to ca. 1 mL in vacuum.
Slow addition of diethyl ether afforded crystallization of the product. It was filtered, washed with
ether, and dried in vacuum.
[Ir(CO)(µ-Cl)(µ-Ph
2
PPy)
2
FeCl
2
]·2CH
2
Cl
2
(5.2): Orange crystalline powder (20 mg, 72%). Crystals
suitable for X-ray analysis were obtained by slow addition of diethyl ether to CH
2
Cl
2
solution.
1
H NMR (500 MHz, CD
2
Cl
2
): δ 6.50 – 10.00 (m, ArH).
31
P{
1
H} NMR (202 MHz, CD
2
Cl
2
): δ 3.03.
IR (KBr, cm
-1
): ν(CO) 2009, 1968. MALDI-MS: m/z [M – COCl]
+
calcd. 845.01, found 844.84. Anal. calcd
for C
37
H
32
Cl
7
FeIrN
2
OP
2
: C 41.19, H 2.99, N 2.60. Found: C 41.56, H 3.15, N 3.09.
-10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
f1 (ppm)
24.37
Ir
Ph
2
P
Ph
2
P
OC
N
N
Cl
5.1
194
Figure 5.9.
1
H and
31
P{
1
H} NMR spectra of 5.2 in CD
2
Cl
2
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0
f1 (ppm)
5.32 Dichloromethane
6.78
7.28
7.48
9.26
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
3.03
Ir
Ph
2
P
Ph
2
P
OC
N
Fe
Cl
N
Cl
Cl
5.2
195
[IrCl(CO)(µ-Ph
2
PPy)
2
CoCl
2
]·2CH
2
Cl
2
(5.3): Green crystalline powder (15 mg, 54%). Crystals suitable
for X-ray analysis were obtained by slow addition of diethyl ether to CH
2
Cl
2
solution.
1
H NMR (600 MHz, CD
2
Cl
2
): δ 10.02 (br s), 9.28 (br s), 8.10 (br s), 2.65 (br s).
IR (KBr, cm
-1
): ν(CO) 2010, 1968.
MALDI-MS: m/z [M – Cl]
+
calcd. 876.00, found 875.94; [M – COCl]
+
calcd. 848.01, found 848.02.
Anal. calcd for C
37
H
32
Cl
7
CoIrN
2
OP
2
: C 41.08, H 2.98, N 2.59. Found: C 41.12, H 3.10, N 2.70.
Figure 5.10.
1
H NMR spectrum of 5.3 in CD
2
Cl
2
.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0
f1 (ppm)
2.65
5.32 Dichloromethane
8.10
9.28
10.02
Ir
Ph
2
P
Ph
2
P
OC
N
Co
Cl
N
Cl
Cl
5.3
196
[Ir(CO)(µ-Cl)(µ-Ph
2
PPy)
2
NiCl
2
]·2CH
2
Cl
2
(5.4): In a glovebox, 5.1 (100 mg, 0.128 mmol) and
[NiCl
2
(DME)] (28 mg, 0.128 mmol) were mixed with dry CH
2
Cl
2
(5 mL) and stirred at room
temperature overnight. The dark-pink suspension was concentrated to ca. 2 mL and the resulting
precipitate was filtered, washed with minimal amount of CH
2
Cl
2
, and dried in vacuum. The
compound was obtained as a pink powder (103 mg, 75%). Crystals suitable for X-ray analysis were
obtained by slow evaporation of CH
2
Cl
2
solution.
1
H NMR (500 MHz, CD
2
Cl
2
): δ 5.80 – 6.90 (m, ArH).
31
P{
1
H} NMR (202 MHz, CD
2
Cl
2
): δ 24.42.
IR (KBr, cm
-1
): ν(CO) 2016, 2010, 1967.
MALDI-MS: m/z [M – Cl]
+
calcd. 875.00, found 875.07; [M – COCl]
+
calcd. 847.01, found 847.05.
Anal. calcd for C
37
H
32
Cl
7
IrN
2
NiOP
2
: C 41.08, H 2.98, N 2.59. Found: C 40.80, H 3.12, N 2.89.
Figure 5.11.
1
H and
31
P{
1
H} NMR spectra of 5.4 in CD
2
Cl
2
.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
f1 (ppm)
5.32 Dichloromethane
6.05
6.26
6.37
6.62
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
f1 (ppm)
24.42
Ir
Ph
2
P
Ph
2
P
OC
N
Ni
Cl
N
Cl
Cl
5.4
197
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201
Appendix. X-Ray Crystallography Data
Crystal Structure of 2.7
A yellow prism-like specimen of C
22
H
37
IrNP, approximate dimensions 0.213 mm x 0.233 mm x 0.321
mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured on a Bruker
APEX DUO system equipped with a TRIUMPH curved-crystal monochromator and a MoKα fine-focus tube
(λ = 0.71073 Å).
A total of 2520 frames were collected. The total exposure time was 0.70 hours. The frames were
integrated with the Bruker SAINT software package using a SAINT V8.37A (Bruker AXS, 2013) algorithm.
The integration of the data using an orthorhombic unit cell yielded a total of 43910 reflections to a
maximum θ angle of 27.47° (0.77 Å resolution), of which 4809 were independent (average redundancy
9.131, completeness = 100.0%, R
int
= 4.32%, R
sig
= 1.97%) and 4770 (99.19%) were greater than 2σ(F
2
). The
final cell constants of a = 10.5276(13) Å, b = 10.7464(14) Å, c = 18.567(2) Å, volume = 2100.6(5) Å
3
, are
based upon the refinement of the XYZ-centroids of 9753 reflections above 20 σ(I) with 4.382° < 2θ <
202
61.05°. Data were corrected for absorption effects using the multi-scan method (SADABS). The ratio of
minimum to maximum apparent transmission was 0.530. The calculated minimum and maximum
transmission coefficients (based on crystal size) are 0.2320 and 0.3410.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 21 21 21, with Z = 4 for the formula unit, C
22
H
37
IrNP. The final anisotropic full-matrix least-squares
refinement on F
2
with 237 variables converged at R1 = 1.43%, for the observed data and wR2 = 3.54% for
all data. The goodness-of-fit was 1.128. The largest peak in the final difference electron density synthesis
was 2.336 e
-
/Å
3
and the largest hole was -0.666 e
-
/Å
3
with an RMS deviation of 0.086 e
-
/Å
3
. On the basis
of the final model, the calculated density was 1.703 g/cm
3
and F(000), 1072 e
-
.
Table A.1. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 2.7.
x/a y/b z/c U(eq)
C1 0.7369(4) 0.8725(3) 0.3433(2) 0.0148(7)
C2 0.6858(4) 0.9902(3) 0.3486(2) 0.0175(8)
C3 0.5912(4) 1.0114(3) 0.3988(2) 0.0182(8)
C4 0.5560(3) 0.9151(4) 0.44416(19) 0.0153(7)
C5 0.6104(3) 0.7981(3) 0.43586(19) 0.0122(7)
C6 0.5768(4) 0.6933(3) 0.4860(2) 0.0135(7)
C7 0.4407(3) 0.5111(3) 0.3980(2) 0.0144(7)
C8 0.4141(4) 0.6267(4) 0.3511(2) 0.0188(8)
C9 0.3280(4) 0.4969(4) 0.4499(2) 0.0227(9)
C10 0.4465(4) 0.3971(4) 0.3480(2) 0.0203(8)
C11 0.6166(3) 0.4348(3) 0.52407(18) 0.0124(7)
C12 0.5216(4) 0.4620(4) 0.5856(2) 0.0173(8)
C13 0.6027(4) 0.2986(3) 0.5011(2) 0.0173(8)
C14 0.7507(4) 0.4529(3) 0.55559(18) 0.0152(8)
C15 0.7173(4) 0.5228(3) 0.25411(18) 0.0146(7)
C16 0.8004(4) 0.6247(3) 0.25794(18) 0.0135(7)
C17 0.9229(4) 0.6259(3) 0.29285(19) 0.0135(7)
C18 1.0185(4) 0.5190(4) 0.2888(2) 0.0167(8)
C19 0.9987(3) 0.4260(4) 0.35048(19) 0.0161(7)
C20 0.8563(3) 0.4073(3) 0.36654(19) 0.0134(6)
C21 0.7905(4) 0.3209(3) 0.3131(2) 0.0168(8)
C22 0.7578(4) 0.3874(3) 0.2427(2) 0.0185(8)
N1 0.6987(3) 0.7752(3) 0.38461(16) 0.0125(6)
P1 0.60014(9) 0.54021(8) 0.44271(5) 0.00903(17)
Ir1 0.76939(2) 0.58382(2) 0.36990(2) 0.00789(4)
203
Table A.2. Bond lengths (Å) for 2.7.
C1-N1 1.358(4) C1-C2 1.378(5)
C1-H1 0.95 C2-C3 1.384(6)
C2-H2 0.95 C3-C4 1.385(5)
C3-H3 0.95 C4-C5 1.390(5)
C4-H4 0.95 C5-N1 1.353(5)
C5-C6 1.504(5) C6-P1 1.847(4)
C6-H6A 0.99 C6-H6B 0.99
C7-C9 1.537(5) C7-C10 1.539(5)
C7-C8 1.543(5) C7-P1 1.898(4)
C8-H8A 0.98 C8-H8B 0.98
C8-H8C 0.98 C9-H9A 0.98
C9-H9B 0.98 C9-H9C 0.98
C10-H10A 0.98 C10-H10B 0.98
C10-H10C 0.98 C11-C13 1.531(5)
C11-C14 1.541(5) C11-C12 1.546(5)
C11-P1 1.896(4) C12-H12A 0.98
C12-H12B 0.98 C12-H12C 0.98
C13-H13A 0.98 C13-H13B 0.98
C13-H13C 0.98 C14-H14A 0.98
C14-H14B 0.98 C14-H14C 0.98
C15-C16 1.404(6) C15-C22 1.530(5)
C15-Ir1 2.314(3) C15-H15 1.0
C16-C17 1.443(5) C16-Ir1 2.150(3)
C16-H16 1.0 C17-C18 1.529(5)
C17-Ir1 2.206(4) C17-H17 1.0
C18-C19 1.535(5) C18-H18A 0.99
C18-H18B 0.99 C19-C20 1.541(5)
C19-H19A 0.99 C19-H19B 0.99
C20-C21 1.525(5) C20-Ir1 2.107(3)
C20-H20 1.0 C21-C22 1.531(5)
C21-H21A 0.99 C21-H21B 0.99
C22-H22A 0.99 C22-H22B 0.99
N1-Ir1 2.204(3) P1-Ir1 2.2851(10)
Ir1-H1M 1.46(5)
Table A.3. Bond angles (°) for 2.7.
N1-C1-C2 123.4(4) N1-C1-H1 118.3
C2-C1-H1 118.3 C1-C2-C3 118.7(4)
C1-C2-H2 120.6 C3-C2-H2 120.6
C2-C3-C4 118.7(3) C2-C3-H3 120.7
C4-C3-H3 120.7 C3-C4-C5 119.9(3)
C3-C4-H4 120.1 C5-C4-H4 120.1
N1-C5-C4 121.7(3) N1-C5-C6 117.4(3)
C4-C5-C6 120.8(3) C5-C6-P1 111.5(3)
C5-C6-H6A 109.3 P1-C6-H6A 109.3
C5-C6-H6B 109.3 P1-C6-H6B 109.3
204
H6A-C6-H6B 108.0 C9-C7-C10 109.3(3)
C9-C7-C8 107.1(3) C10-C7-C8 107.9(3)
C9-C7-P1 115.1(3) C10-C7-P1 111.1(3)
C8-C7-P1 106.0(2) C7-C8-H8A 109.5
C7-C8-H8B 109.5 H8A-C8-H8B 109.5
C7-C8-H8C 109.5 H8A-C8-H8C 109.5
H8B-C8-H8C 109.5 C7-C9-H9A 109.5
C7-C9-H9B 109.5 H9A-C9-H9B 109.5
C7-C9-H9C 109.5 H9A-C9-H9C 109.5
H9B-C9-H9C 109.5 C7-C10-H10A 109.5
C7-C10-H10B 109.5 H10A-C10-H10B 109.5
C7-C10-H10C 109.5 H10A-C10-H10C 109.5
H10B-C10-H10C 109.5 C13-C11-C14 108.3(3)
C13-C11-C12 109.0(3) C14-C11-C12 106.8(3)
C13-C11-P1 109.9(2) C14-C11-P1 108.1(2)
C12-C11-P1 114.6(3) C11-C12-H12A 109.5
C11-C12-H12B 109.5 H12A-C12-H12B 109.5
C11-C12-H12C 109.5 H12A-C12-H12C 109.5
H12B-C12-H12C 109.5 C11-C13-H13A 109.5
C11-C13-H13B 109.5 H13A-C13-H13B 109.5
C11-C13-H13C 109.5 H13A-C13-H13C 109.5
H13B-C13-H13C 109.5 C11-C14-H14A 109.5
C11-C14-H14B 109.5 H14A-C14-H14B 109.5
C11-C14-H14C 109.5 H14A-C14-H14C 109.5
H14B-C14-H14C 109.5 C16-C15-C22 125.1(4)
C16-C15-Ir1 65.42(18) C22-C15-Ir1 109.4(2)
C16-C15-H15 115.2 C22-C15-H15 115.2
Ir1-C15-H15 115.2 C15-C16-C17 125.9(3)
C15-C16-Ir1 78.2(2) C17-C16-Ir1 72.8(2)
C15-C16-H16 116.9 C17-C16-H16 116.9
Ir1-C16-H16 116.9 C16-C17-C18 124.0(3)
C16-C17-Ir1 68.6(2) C18-C17-Ir1 111.1(2)
C16-C17-H17 114.7 C18-C17-H17 114.7
Ir1-C17-H17 114.7 C17-C18-C19 111.3(3)
C17-C18-H18A 109.4 C19-C18-H18A 109.4
C17-C18-H18B 109.4 C19-C18-H18B 109.4
H18A-C18-H18B 108.0 C18-C19-C20 111.2(3)
C18-C19-H19A 109.4 C20-C19-H19A 109.4
C18-C19-H19B 109.4 C20-C19-H19B 109.4
H19A-C19-H19B 108.0 C21-C20-C19 113.3(3)
C21-C20-Ir1 111.7(2) C19-C20-Ir1 108.1(2)
C21-C20-H20 107.8 C19-C20-H20 107.8
Ir1-C20-H20 107.8 C20-C21-C22 111.9(3)
C20-C21-H21A 109.2 C22-C21-H21A 109.2
C20-C21-H21B 109.2 C22-C21-H21B 109.2
H21A-C21-H21B 107.9 C15-C22-C21 112.8(3)
C15-C22-H22A 109.0 C21-C22-H22A 109.0
205
C15-C22-H22B 109.0 C21-C22-H22B 109.0
H22A-C22-H22B 107.8 C5-N1-C1 117.4(3)
C5-N1-Ir1 119.3(2) C1-N1-Ir1 123.3(2)
C6-P1-C11 101.36(16) C6-P1-C7 102.69(17)
C11-P1-C7 109.32(17) C6-P1-Ir1 100.30(12)
C11-P1-Ir1 121.52(12) C7-P1-Ir1 117.66(13)
C20-Ir1-C16 95.13(14) C20-Ir1-N1 172.02(13)
C16-Ir1-N1 88.87(12) C20-Ir1-C17 81.20(14)
C16-Ir1-C17 38.68(14) N1-Ir1-C17 97.83(13)
C20-Ir1-P1 99.88(10) C16-Ir1-P1 137.10(11)
N1-Ir1-P1 81.66(8) C17-Ir1-P1 175.77(11)
C20-Ir1-C15 79.64(14) C16-Ir1-C15 36.43(14)
N1-Ir1-C15 107.44(12) C17-Ir1-C15 68.22(14)
P1-Ir1-C15 107.88(10) C20-Ir1-H1M 85.2(18)
C16-Ir1-H1M 134.0(19) N1-Ir1-H1M 87.0(18)
C17-Ir1-H1M 96.8(19) P1-Ir1-H1M 87.4(19)
C15-Ir1-H1M 160.1(19)
Table A.4. Torsion angles (°) for 2.7.
N1-C1-C2-C3 0.4(6) C1-C2-C3-C4 3.1(6)
C2-C3-C4-C5 -3.6(6) C3-C4-C5-N1 0.6(6)
C3-C4-C5-C6 177.9(3) N1-C5-C6-P1 -28.2(4)
C4-C5-C6-P1 154.4(3) C22-C15-C16-C17 -38.9(5)
Ir1-C15-C16-C17 58.3(3) C22-C15-C16-Ir1 -97.2(3)
C15-C16-C17-C18 41.0(5) Ir1-C16-C17-C18 101.7(3)
C15-C16-C17-Ir1 -60.7(3) C16-C17-C18-C19 -90.3(4)
Ir1-C17-C18-C19 -12.6(4) C17-C18-C19-C20 38.2(4)
C18-C19-C20-C21 78.6(4) C18-C19-C20-Ir1 -45.8(4)
C19-C20-C21-C22 -79.5(4) Ir1-C20-C21-C22 42.9(4)
C16-C15-C22-C21 86.8(4) Ir1-C15-C22-C21 13.7(4)
C20-C21-C22-C15 -36.5(5) C4-C5-N1-C1 2.8(5)
C6-C5-N1-C1 -174.6(3) C4-C5-N1-Ir1 -175.4(3)
C6-C5-N1-Ir1 7.1(4) C2-C1-N1-C5 -3.4(5)
C2-C1-N1-Ir1 174.8(3) C5-C6-P1-C11 158.3(3)
C5-C6-P1-C7 -88.7(3) C5-C6-P1-Ir1 32.9(3)
C13-C11-P1-C6 165.5(3) C14-C11-P1-C6 -76.5(3)
C12-C11-P1-C6 42.4(3) C13-C11-P1-C7 57.6(3)
C14-C11-P1-C7 175.5(2) C12-C11-P1-C7 -65.5(3)
C13-C11-P1-Ir1 -84.8(3) C14-C11-P1-Ir1 33.2(3)
C12-C11-P1-Ir1 152.1(2) C9-C7-P1-C6 -64.5(3)
C10-C7-P1-C6 170.7(3) C8-C7-P1-C6 53.7(3)
C9-C7-P1-C11 42.6(3) C10-C7-P1-C11 -82.3(3)
C8-C7-P1-C11 160.7(2) C9-C7-P1-Ir1 -173.4(2)
C10-C7-P1-Ir1 61.7(3) C8-C7-P1-Ir1 -55.3(3)
Table A.5. Anisotropic atomic displacement parameters (Å
2
) for 2.7.
U
11
U
22
U
33
U
12
U
13
U
23
206
C1 0.0145(18) 0.0164(16) 0.0134(16) -0.0020(14) 0.0035(15) 0.0017(13)
C2 0.0214(18) 0.0121(17) 0.0190(19) -0.0029(15) 0.0002(15) 0.0005(14)
C3 0.0201(19) 0.0112(17) 0.0232(19) 0.0018(15) -0.0017(16) -0.0008(15)
C4 0.0149(17) 0.0148(16) 0.0162(17) -0.0022(17) 0.0012(13) -0.0007(17)
C5 0.0095(17) 0.0164(17) 0.0108(17) -0.0016(13) -0.0012(14) -0.0027(13)
C6 0.0130(18) 0.0148(18) 0.0126(17) 0.0000(14) 0.0034(14) -0.0015(14)
C7 0.0107(16) 0.0172(18) 0.0153(17) -0.0020(14) -0.0026(14) 0.0018(14)
C8 0.0140(18) 0.0238(19) 0.018(2) 0.0000(15) -0.0050(15) 0.0038(15)
C9 0.0097(18) 0.034(2) 0.025(2) -0.0043(17) -0.0005(16) 0.0030(18)
C10 0.0183(19) 0.020(2) 0.0228(19) -0.0059(15) -0.0060(15) -0.0016(16)
C11 0.0145(17) 0.0145(18) 0.0084(15) 0.0005(14) 0.0003(12) 0.0023(13)
C12 0.0183(19) 0.0226(19) 0.0110(17) 0.0027(15) 0.0041(15) 0.0029(14)
C13 0.020(2) 0.0129(17) 0.0185(19) -0.0008(15) 0.0028(16) 0.0032(14)
C14 0.015(2) 0.0222(18) 0.0085(16) 0.0008(14) -0.0024(14) 0.0038(12)
C15 0.0150(18) 0.0199(18) 0.0090(16) 0.0012(15) -0.0014(14) -0.0015(13)
C16 0.018(2) 0.0162(16) 0.0068(16) 0.0013(14) 0.0030(13) 0.0016(12)
C17 0.0180(19) 0.0128(16) 0.0096(17) 0.0002(14) 0.0046(15) 0.0016(13)
C18 0.0134(18) 0.0226(19) 0.0140(18) 0.0043(15) 0.0042(14) 0.0021(15)
C19 0.0140(16) 0.0196(18) 0.0147(17) 0.0070(16) 0.0017(12) 0.0030(16)
C20 0.0162(16) 0.0133(16) 0.0107(15) 0.0049(13) 0.0034(13) 0.0033(16)
C21 0.020(2) 0.0098(16) 0.0206(19) -0.0010(14) 0.0057(16) -0.0022(13)
C22 0.025(2) 0.0168(17) 0.0141(17) -0.0019(15) 0.0020(15) -0.0052(12)
N1 0.0135(14) 0.0121(14) 0.0119(14) -0.0023(11) -0.0016(11) -0.0021(11)
P1 0.0083(4) 0.0105(4) 0.0083(4) -0.0007(3) -0.0002(3) 0.0011(3)
Ir1 0.00758(6) 0.00951(6) 0.00658(6) -0.00011(4) 0.00043(4) 0.00021(5)
Table A.6. Hydrogen atoms coordinates and isotropic atomic displacement parameters (Å
2
) for 2.7.
x/a y/b z/c U(eq)
H1 0.8022 0.8587 0.3089 0.018
H2 0.715 1.0555 0.3183 0.021
H3 0.5512 1.0904 0.4021 0.022
H4 0.4947 0.929 0.4809 0.018
H6A 0.487 0.7016 0.5011 0.016
H6B 0.6305 0.6985 0.5297 0.016
H8A 0.4873 0.6428 0.3198 0.028
H8B 0.3995 0.699 0.3822 0.028
H8C 0.3386 0.6119 0.3214 0.028
H9A 0.2484 0.4993 0.4226 0.034
H9B 0.3291 0.5651 0.485 0.034
H9C 0.3347 0.4172 0.4753 0.034
H10A 0.3671 0.3908 0.3206 0.03
H10B 0.4581 0.3216 0.3769 0.03
H10C 0.5179 0.4061 0.3145 0.03
H12A 0.5232 0.551 0.597 0.026
H12B 0.5455 0.414 0.6284 0.026
H12C 0.4358 0.4382 0.5703 0.026
H13A 0.5141 0.282 0.4882 0.026
207
H13B 0.6279 0.2443 0.541 0.026
H13C 0.6574 0.2825 0.4594 0.026
H14A 0.8143 0.4319 0.519 0.023
H14B 0.7616 0.3986 0.5975 0.023
H14C 0.7616 0.5399 0.5703 0.023
H15 0.6287 0.543 0.2386 0.018
H16 0.7676 0.7063 0.2398 0.016
H17 0.9616 0.7104 0.2984 0.016
H18A 1.1058 0.553 0.2913 0.02
H18B 1.0091 0.4755 0.2421 0.02
H19A 1.0419 0.4569 0.3943 0.019
H19B 1.0372 0.3451 0.3373 0.019
H20 0.8488 0.3693 0.4155 0.016
H21A 0.7116 0.2882 0.3351 0.02
H21B 0.8467 0.2493 0.3027 0.02
H22A 0.8328 0.3855 0.2105 0.022
H22B 0.6881 0.342 0.2184 0.022
H1M 0.844(5) 0.603(4) 0.435(2) 0.024(12)
208
Crystal Structure of 2.8
A pale yellow prism-like specimen of C
29
H
48
Ir
2
N
2
OP
2
, approximate dimensions 0.080 mm x 0.090 mm
x 0.110 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured on
a Bruker APEX DUO system equipped with a TRIUMPH curved-crystal monochromator and a MoKα fine-
focus tube (λ = 0.71073 Å).
A total of 2035 frames were collected. The total exposure time was 15.10 hours. The frames were
integrated with the Bruker SAINT software package using a SAINT V8.37A (Bruker AXS, 2013) algorithm.
The integration of the data using a monoclinic unit cell yielded a total of 53562 reflections to a maximum
θ angle of 27.55° (0.77 Å resolution), of which 7407 were independent (average redundancy 7.231,
completeness = 99.6%, R
int
= 5.11%, R
sig
= 2.77%) and 6340 (85.59%) were greater than 2σ(F
2
). The final
cell constants of a = 14.836(5) Å, b = 15.464(5) Å, c = 15.385(5) Å, β = 114.159(6)°, volume = 3220.5(19)
Å
3
, are based upon the refinement of the XYZ-centroids of 539 reflections above 20 σ(I) with 3.983° < 2θ
< 51.18°. Data were corrected for absorption effects using the multi-scan method (SADABS). The ratio of
209
minimum to maximum apparent transmission was 0.711. The calculated minimum and maximum
transmission coefficients (based on crystal size) are 0.4590 and 0.5540.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/c 1, with Z = 4 for the formula unit, C
29
H
48
Ir
2
N
2
OP
2
. The final anisotropic full-matrix least-
squares refinement on F
2
with 575 variables converged at R1 = 3.30%, for the observed data and wR2 =
8.00% for all data. The goodness-of-fit was 1.107. The largest peak in the final difference electron density
synthesis was 2.379 e
-
/Å
3
and the largest hole was -1.521 e
-
/Å
3
with an RMS deviation of 0.155 e
-
/Å
3
. On
the basis of the final model, the calculated density was 1.829 g/cm
3
and F(000), 1712 e
-
.
Table A.7. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 2.8.
x/a y/b z/c U(eq)
C1 0.1797(8) 0.4078(9) 0.1160(10) 0.0282(13)
C2 0.1417(7) 0.4913(6) 0.0867(6) 0.035(2)
C3 0.1955(8) 0.5540(7) 0.0648(7) 0.044(3)
C4 0.2893(8) 0.5356(6) 0.0730(7) 0.040(2)
C5 0.3271(8) 0.4543(6) 0.1025(9) 0.035(2)
C6 0.4239(8) 0.4246(7) 0.1045(8) 0.043(2)
C7 0.5611(7) 0.3776(7) 0.2995(6) 0.038(2)
C8 0.5031(7) 0.4527(6) 0.3227(6) 0.038(2)
C9 0.6535(8) 0.4161(11) 0.2926(9) 0.044(3)
C10 0.5899(8) 0.3150(7) 0.3801(6) 0.043(2)
C11 0.5307(7) 0.2649(7) 0.1215(7) 0.048(2)
C12 0.5960(8) 0.3174(9) 0.0849(9) 0.044(3)
C13 0.6003(9) 0.1940(7) 0.1968(10) 0.062(3)
C14 0.4544(9) 0.2163(10) 0.0450(10) 0.073(4)
C15 0.2447(16) 0.4168(11) 0.3429(8) 0.030(3)
C16 0.2805(12) 0.4437(8) 0.4356(7) 0.039(3)
C17 0.2395(17) 0.4096(11) 0.4948(9) 0.047(3)
C18 0.1636(8) 0.3529(6) 0.4576(6) 0.045(2)
C19 0.1294(6) 0.3288(6) 0.3624(6) 0.0353(17)
C20 0.0423(6) 0.2679(6) 0.3178(6) 0.0420(19)
C21 -0.0858(6) 0.1786(6) 0.1433(7) 0.046(2)
C22 -0.1358(7) 0.2589(7) 0.0869(9) 0.060(3)
C23 -0.1425(7) 0.1512(7) 0.2032(9) 0.059(3)
C24 -0.0893(7) 0.1078(7) 0.0728(8) 0.058(3)
C25 0.1182(6) 0.1069(6) 0.2761(7) 0.0421(19)
C26 0.2115(6) 0.1377(6) 0.3602(6) 0.044(2)
C27 0.1488(10) 0.0597(11) 0.2052(11) 0.046(3)
C28 0.0650(8) 0.0431(8) 0.3158(9) 0.054(3)
210
C29 0.3871(8) 0.1820(10) 0.2622(16) 0.032(3)
N1 0.2742(8) 0.3942(8) 0.1254(13) 0.0300(18)
N2 0.1749(9) 0.3572(6) 0.3065(6) 0.031(2)
O1 0.428(2) 0.1233(14) 0.3100(18) 0.054(4)
P1 0.4712(3) 0.3304(3) 0.1863(4) 0.0240(9)
P2 0.05048(12) 0.20518(11) 0.22183(14) 0.0388(4)
Ir1 0.33184(15) 0.27719(13) 0.19180(14) 0.0216(2)
Ir2 0.12365(2) 0.30692(2) 0.16259(2) 0.02778(7)
Table A.8. Hydrogen atoms coordinates and isotropic atomic displacement parameters (Å
2
) for 2.8.
x/a y/b z/c U(eq)
H1 0.040(5) 0.276(4) 0.041(4) 0.033
H2 0.0774 0.505 0.0819 0.042
H3 0.1677 0.6096 0.0441 0.053
H4 0.3273 0.5782 0.0585 0.048
H6A 0.4724 0.4725 0.1262 0.052
H6B 0.4155 0.4079 0.0395 0.052
H8A 0.4827 0.4956 0.2713 0.057
H8B 0.4446 0.4291 0.3286 0.057
H8C 0.546 0.4804 0.3828 0.057
H9A 0.6335 0.457 0.2394 0.066
H9B 0.6933 0.4462 0.352 0.066
H9C 0.6926 0.3695 0.282 0.066
H10A 0.5303 0.2911 0.3837 0.065
H10B 0.6288 0.2681 0.3698 0.065
H10C 0.6295 0.3448 0.4399 0.065
H12A 0.646 0.349 0.138 0.065
H12B 0.6286 0.2782 0.0568 0.065
H12C 0.5549 0.3586 0.0364 0.065
H13A 0.6528 0.2237 0.2497 0.093
H13B 0.5603 0.1597 0.2215 0.093
H13C 0.6297 0.1557 0.1648 0.093
H14A 0.4144 0.1837 0.0711 0.11
H14B 0.412 0.2565 -0.0038 0.11
H14C 0.4857 0.1761 0.0166 0.11
H15 0.2713 0.4422 0.3023 0.037
H16 0.3325 0.4849 0.4591 0.047
H17 0.2642 0.4257 0.5601 0.057
H18 0.1338 0.3297 0.4965 0.054
H20A -0.0197 0.3019 0.2929 0.05
H20B 0.0399 0.2281 0.3673 0.05
H22A -0.1343 0.3052 0.131 0.091
H22B -0.1008 0.2778 0.0483 0.091
H22C -0.2045 0.2454 0.0451 0.091
H23A -0.1116 0.0995 0.2403 0.089
H23B -0.1406 0.1982 0.2466 0.089
H23C -0.2113 0.1384 0.161 0.089
211
H24A -0.0574 0.0555 0.1078 0.088
H24B -0.1583 0.095 0.031 0.088
H24C -0.0546 0.1275 0.0342 0.088
H26A 0.1927 0.168 0.4062 0.066
H26B 0.2527 0.0877 0.3911 0.066
H26C 0.2486 0.177 0.3371 0.066
H27A 0.0897 0.0397 0.151 0.069
H27B 0.1861 0.0993 0.1824 0.069
H27C 0.1903 0.01 0.2365 0.069
H28A 0.0453 0.0731 0.3614 0.081
H28B 0.0062 0.0202 0.2634 0.081
H28C 0.1097 -0.0046 0.348 0.081
Table A.9. Bond lengths (Å) for 2.8.
P2-C20 1.812(9) P2-C25 1.825(9)
P2-C21 1.928(8) P2-Ir2 2.3010(18)
Ir2-C1 2.031(11) Ir2-N2 2.169(9)
Ir2-Ir1 2.969(2) Ir2-H1 1.83(6)
C1-N1 1.365(9) C1-C2 1.408(10)
C2-C3 1.382(11) C2-H2 0.95
C3-C4 1.376(12) C3-H3 0.95
C4-C5 1.375(11) C4-H4 0.95
C5-N1 1.352(9) C5-C6 1.497(11)
C6-P1 1.866(9) C6-H6A 0.99
C6-H6B 0.99 C7-C10 1.492(12)
C7-C9 1.538(10) C7-C8 1.571(12)
C7-P1 1.855(8) C8-H8A 0.98
C8-H8B 0.98 C8-H8C 0.98
C9-H9A 0.98 C9-H9B 0.98
C9-H9C 0.98 C10-H10A 0.98
C10-H10B 0.98 C10-H10C 0.98
C11-C14 1.463(13) C11-C12 1.538(11)
C11-C13 1.622(16) C11-P1 1.876(8)
C12-H12A 0.98 C12-H12B 0.98
C12-H12C 0.98 C13-H13A 0.98
C13-H13B 0.98 C13-H13C 0.98
C14-H14A 0.98 C14-H14B 0.98
C14-H14C 0.98 C15-N2 1.327(11)
C15-C16 1.366(10) C15-H15 0.95
C16-C17 1.390(15) C16-H16 0.95
C17-C18 1.355(15) C17-H17 0.95
C18-C19 1.390(11) C18-H18 0.95
C19-N2 1.366(10) C19-C20 1.517(12)
C20-H20A 0.99 C20-H20B 0.99
C21-C22 1.522(13) C21-C24 1.527(15)
C21-C23 1.541(13) C22-H22A 0.98
C22-H22B 0.98 C22-H22C 0.98
212
C23-H23A 0.98 C23-H23B 0.98
C23-H23C 0.98 C24-H24A 0.98
C24-H24B 0.98 C24-H24C 0.98
C25-C27 1.528(16) C25-C26 1.534(13)
C25-C28 1.537(12) C26-H26A 0.98
C26-H26B 0.98 C26-H26C 0.98
C27-H27A 0.98 C27-H27B 0.98
C27-H27C 0.98 C28-H28A 0.98
C28-H28B 0.98 C28-H28C 0.98
C29-O1 1.168(10) C29-Ir1 1.813(8)
N1-Ir1 2.082(6) P1-Ir1 2.258(4)
Table A.10. Bond angles (°) for 2.8.
C20-P2-C25 106.3(4) C20-P2-C21 102.8(4)
C25-P2-C21 110.4(4) C20-P2-Ir2 99.0(3)
C25-P2-Ir2 119.3(3) C21-P2-Ir2 116.2(3)
C1-Ir2-N2 93.6(5) C1-Ir2-P2 173.0(4)
N2-Ir2-P2 82.3(2) C1-Ir2-Ir1 67.8(2)
N2-Ir2-Ir1 89.6(3) P2-Ir2-Ir1 117.67(6)
C1-Ir2-H1 92.(2) N2-Ir2-H1 160.(2)
P2-Ir2-H1 90.(2) Ir1-Ir2-H1 110.(2)
N1-C1-C2 115.8(8) N1-C1-Ir2 113.3(6)
C2-C1-Ir2 130.5(6) C3-C2-C1 121.7(8)
C3-C2-H2 119.2 C1-C2-H2 119.2
C4-C3-C2 119.8(8) C4-C3-H3 120.1
C2-C3-H3 120.1 C5-C4-C3 118.6(8)
C5-C4-H4 120.7 C3-C4-H4 120.7
N1-C5-C4 120.9(8) N1-C5-C6 116.0(7)
C4-C5-C6 123.0(8) C5-C6-P1 110.2(6)
C5-C6-H6A 109.6 P1-C6-H6A 109.6
C5-C6-H6B 109.6 P1-C6-H6B 109.6
H6A-C6-H6B 108.1 C10-C7-C9 110.4(8)
C10-C7-C8 106.7(8) C9-C7-C8 108.4(8)
C10-C7-P1 112.1(6) C9-C7-P1 114.0(6)
C8-C7-P1 104.8(6) C7-C8-H8A 109.5
C7-C8-H8B 109.5 H8A-C8-H8B 109.5
C7-C8-H8C 109.5 H8A-C8-H8C 109.5
H8B-C8-H8C 109.5 C7-C9-H9A 109.5
C7-C9-H9B 109.5 H9A-C9-H9B 109.5
C7-C9-H9C 109.5 H9A-C9-H9C 109.5
H9B-C9-H9C 109.5 C7-C10-H10A 109.5
C7-C10-H10B 109.5 H10A-C10-H10B 109.5
C7-C10-H10C 109.5 H10A-C10-H10C 109.5
H10B-C10-H10C 109.5 C14-C11-C12 111.9(9)
C14-C11-C13 106.5(10) C12-C11-C13 107.9(8)
C14-C11-P1 109.1(7) C12-C11-P1 114.4(7)
C13-C11-P1 106.6(7) C11-C12-H12A 109.5
213
C11-C12-H12B 109.5 H12A-C12-H12B 109.5
C11-C12-H12C 109.5 H12A-C12-H12C 109.5
H12B-C12-H12C 109.5 C11-C13-H13A 109.5
C11-C13-H13B 109.5 H13A-C13-H13B 109.5
C11-C13-H13C 109.5 H13A-C13-H13C 109.5
H13B-C13-H13C 109.5 C11-C14-H14A 109.5
C11-C14-H14B 109.5 H14A-C14-H14B 109.5
C11-C14-H14C 109.5 H14A-C14-H14C 109.5
H14B-C14-H14C 109.5 N2-C15-C16 123.7(10)
N2-C15-H15 118.1 C16-C15-H15 118.1
C15-C16-C17 118.8(10) C15-C16-H16 120.6
C17-C16-H16 120.6 C18-C17-C16 118.6(9)
C18-C17-H17 120.7 C16-C17-H17 120.7
C17-C18-C19 120.1(9) C17-C18-H18 120.0
C19-C18-H18 120.0 N2-C19-C18 121.1(9)
N2-C19-C20 117.6(8) C18-C19-C20 121.3(8)
C19-C20-P2 111.9(6) C19-C20-H20A 109.2
P2-C20-H20A 109.2 C19-C20-H20B 109.2
P2-C20-H20B 109.2 H20A-C20-H20B 107.9
C22-C21-C24 108.2(9) C22-C21-C23 107.9(8)
C24-C21-C23 111.1(8) C22-C21-P2 109.0(6)
C24-C21-P2 108.7(6) C23-C21-P2 111.9(7)
C21-C22-H22A 109.5 C21-C22-H22B 109.5
H22A-C22-H22B 109.5 C21-C22-H22C 109.5
H22A-C22-H22C 109.5 H22B-C22-H22C 109.5
C21-C23-H23A 109.5 C21-C23-H23B 109.5
H23A-C23-H23B 109.5 C21-C23-H23C 109.5
H23A-C23-H23C 109.5 H23B-C23-H23C 109.5
C21-C24-H24A 109.5 C21-C24-H24B 109.5
H24A-C24-H24B 109.5 C21-C24-H24C 109.5
H24A-C24-H24C 109.5 H24B-C24-H24C 109.5
C27-C25-C26 108.8(8) C27-C25-C28 109.2(10)
C26-C25-C28 107.2(7) C27-C25-P2 109.9(7)
C26-C25-P2 105.4(7) C28-C25-P2 116.1(7)
C25-C26-H26A 109.5 C25-C26-H26B 109.5
H26A-C26-H26B 109.5 C25-C26-H26C 109.5
H26A-C26-H26C 109.5 H26B-C26-H26C 109.5
C25-C27-H27A 109.5 C25-C27-H27B 109.5
H27A-C27-H27B 109.5 C25-C27-H27C 109.5
H27A-C27-H27C 109.5 H27B-C27-H27C 109.5
C25-C28-H28A 109.5 C25-C28-H28B 109.5
H28A-C28-H28B 109.5 C25-C28-H28C 109.5
H28A-C28-H28C 109.5 H28B-C28-H28C 109.5
O1-C29-Ir1 176.0(18) C5-N1-C1 123.1(7)
C5-N1-Ir1 124.0(6) C1-N1-Ir1 112.5(5)
C15-N2-C19 117.3(9) C15-N2-Ir2 124.6(7)
C19-N2-Ir2 118.1(7) C7-P1-C6 104.6(5)
214
C7-P1-C11 113.4(5) C6-P1-C11 101.0(5)
C7-P1-Ir1 115.2(3) C6-P1-Ir1 102.3(3)
C11-P1-Ir1 117.4(3) C29-Ir1-N1 173.5(10)
C29-Ir1-P1 97.0(4) N1-Ir1-P1 82.2(3)
C29-Ir1-Ir2 113.8(4) N1-Ir1-Ir2 66.3(2)
P1-Ir1-Ir2 148.15(15)
Table A.11. Anisotropic atomic displacement parameters (Å
2
) for 2.8.
U
11
U
22
U
33
U
12
U
13
U
23
P2 0.0254(7) 0.0382(9) 0.0557(10) -0.0036(6) 0.0197(7) 0.0001(8)
Ir2 0.02224(11) 0.03303(13) 0.02677(12) -0.00045(9) 0.00871(9) -0.00202(9)
C1 0.028(3) 0.034(3) 0.022(2) 0.002(2) 0.009(2) 0.004(2)
C2 0.042(3) 0.038(4) 0.026(5) 0.014(3) 0.014(3) 0.005(3)
C3 0.057(4) 0.037(4) 0.042(7) 0.013(3) 0.025(4) 0.011(4)
C4 0.054(3) 0.035(4) 0.036(6) 0.004(3) 0.024(4) 0.005(4)
C5 0.037(3) 0.036(4) 0.036(5) -0.001(3) 0.018(3) 0.002(4)
C6 0.042(3) 0.048(5) 0.045(4) 0.001(3) 0.023(3) 0.006(4)
C7 0.036(4) 0.041(5) 0.034(4) -0.018(3) 0.013(3) -0.007(3)
C8 0.042(4) 0.040(5) 0.034(4) -0.011(4) 0.016(4) -0.009(3)
C9 0.040(5) 0.058(7) 0.028(5) -0.027(5) 0.008(4) -0.012(4)
C10 0.036(5) 0.054(6) 0.031(4) -0.011(4) 0.005(3) 0.001(4)
C11 0.042(4) 0.053(4) 0.065(6) -0.013(3) 0.038(4) -0.024(4)
C12 0.030(5) 0.065(7) 0.046(6) -0.008(4) 0.026(5) -0.017(5)
C13 0.056(6) 0.049(5) 0.096(8) -0.003(5) 0.047(6) -0.016(5)
C14 0.053(6) 0.097(9) 0.085(7) -0.030(6) 0.044(5) -0.058(7)
C15 0.032(6) 0.034(5) 0.024(4) 0.004(4) 0.010(4) 0.002(4)
C16 0.046(5) 0.043(6) 0.022(4) 0.008(5) 0.009(4) 0.000(4)
C17 0.061(8) 0.056(6) 0.028(4) 0.009(5) 0.022(4) 0.001(4)
C18 0.055(5) 0.049(5) 0.037(4) 0.014(4) 0.025(4) 0.005(3)
C19 0.035(4) 0.041(4) 0.035(3) 0.009(3) 0.020(3) 0.008(3)
C20 0.038(4) 0.050(5) 0.047(4) 0.004(3) 0.026(3) 0.011(3)
C21 0.017(3) 0.046(5) 0.067(5) -0.004(3) 0.008(3) 0.013(4)
C22 0.022(4) 0.060(6) 0.080(7) -0.002(4) 0.002(4) 0.023(5)
C23 0.028(4) 0.060(6) 0.089(7) -0.002(4) 0.023(5) 0.018(5)
C24 0.034(5) 0.059(6) 0.070(6) -0.009(4) 0.009(4) 0.006(4)
C25 0.034(4) 0.043(4) 0.053(4) 0.006(3) 0.021(3) 0.018(3)
C26 0.032(4) 0.054(5) 0.046(4) 0.008(3) 0.017(3) 0.017(4)
C27 0.042(6) 0.036(6) 0.060(6) 0.009(5) 0.021(5) 0.016(4)
C28 0.042(5) 0.053(6) 0.070(7) -0.003(4) 0.026(5) 0.024(5)
C29 0.021(5) 0.023(3) 0.056(8) -0.003(3) 0.018(5) 0.001(4)
N1 0.031(3) 0.031(4) 0.030(3) 0.0031(19) 0.015(2) 0.002(3)
N2 0.034(4) 0.036(4) 0.025(3) 0.002(3) 0.014(3) 0.001(3)
O1 0.045(4) 0.033(3) 0.083(11) 0.005(2) 0.025(7) 0.018(5)
P1 0.0196(13) 0.0288(17) 0.0256(14) -0.0050(11) 0.0112(11) -0.0071(12)
Ir1 0.0181(4) 0.0230(3) 0.0260(4) -0.0019(2) 0.0113(4) -0.0053(3)
215
Crystal Structure of 3.3
Table A.12. Sample and crystal data for 3.3.
Chemical formula C
31
H
53
F
3
Ir
2
N
2
O
7
P
2
S
Formula weight 1101.15 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.010 x 0.040 x 0.200 mm
Crystal system monoclinic
Space group P 21
Unit cell dimensions a = 13.5463(16) Å α = 90°
b = 8.4832(10) Å β = 111.787(2)°
c = 17.629(2) Å γ = 90°
Volume 1881.1(4) Å
3
Z 2
Absorption coefficient 7.268 mm
-1
F(000) 1072
Table A.13. Data collection and structure refinement for 3.3.
Diffractometer Bruker APEX DUO
216
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.619 to 27.481°
Index ranges -17<=h<=17, -11<=k<=11, -22<=l<=22
Absorption correction multi-scan
Structure solution technique direct methods
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXTL XL 2018/3 (Bruker AXS, 2018)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 8610 / 2 / 455
Goodness-of-fit on F
2
0.995
Δ/σ
max
0.001
Final R indices 8610 data; I>2σ(I) R1 = 0.0203, wR2 = 0.0405
all data R1 = 0.0229, wR2 = 0.0411
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0062P)
2
]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 1.372 and -0.582 eÅ
-3
R.M.S. deviation from mean 0.105 eÅ
-3
Table A.14. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 3.3.
x/a y/b z/c U(eq)
C1 0.4125(4) 0.5676(7) 0.3902(3) 0.0118(12)
C2 0.4925(5) 0.1634(7) 0.3851(4) 0.0135(13)
C3 0.6599(5) 0.2074(7) 0.2621(4) 0.0151(13)
C4 0.7233(5) 0.1172(7) 0.2346(4) 0.0160(14)
C5 0.8292(5) 0.1638(8) 0.2532(4) 0.0175(14)
C6 0.8654(5) 0.2951(7) 0.3002(4) 0.0167(13)
C7 0.7992(4) 0.3807(8) 0.3291(3) 0.0116(11)
C8 0.8368(5) 0.5230(7) 0.3817(3) 0.0124(12)
C9 0.8156(5) 0.4421(7) 0.5394(3) 0.0132(12)
C10 0.8355(5) 0.2726(7) 0.5148(4) 0.0156(13)
C11 0.7345(5) 0.4294(7) 0.5817(3) 0.0140(13)
C12 0.9211(5) 0.5081(7) 0.5996(4) 0.0169(14)
C13 0.7225(5) 0.8171(7) 0.5299(4) 0.0184(14)
C14 0.8768(5) 0.8341(7) 0.4830(4) 0.0172(14)
C15 0.7622(5) 0.7740(7) 0.4614(4) 0.0153(13)
C16 0.6919(5) 0.8605(8) 0.3834(3) 0.0192(13)
C17 0.1848(5) 0.2036(7) 0.2270(4) 0.0148(13)
C18 0.0816(5) 0.1481(8) 0.1934(4) 0.0184(14)
C19 0.0183(5) 0.1927(8) 0.1140(4) 0.0195(14)
C20 0.0609(5) 0.2904(7) 0.0719(4) 0.0179(13)
C21 0.1665(5) 0.3430(7) 0.1082(3) 0.0142(13)
C22 0.2168(5) 0.4437(8) 0.0630(3) 0.0162(13)
C23 0.4213(5) 0.5854(7) 0.0743(4) 0.0177(14)
C24 0.4811(5) 0.4335(8) 0.0724(4) 0.0240(16)
217
C25 0.3552(5) 0.6299(9) -0.0159(4) 0.0231(15)
C26 0.5032(5) 0.7141(8) 0.1145(4) 0.0227(15)
C27 0.2782(5) 0.7403(7) 0.1564(4) 0.0158(13)
C28 0.1835(5) 0.6990(8) 0.1812(4) 0.0190(14)
C29 0.2376(5) 0.8535(8) 0.0835(4) 0.0228(14)
C30 0.3642(5) 0.8273(7) 0.2280(4) 0.0178(14)
C31 0.8336(6) 0.5972(8) 0.1100(4) 0.0295(17)
F1 0.8177(4) 0.4560(5) 0.1345(2) 0.0417(11)
F2 0.7397(3) 0.6420(6) 0.0505(3) 0.0422(12)
F3 0.9036(3) 0.5820(5) 0.0730(3) 0.0378(11)
Ir1 0.59861(2) 0.46300(2) 0.35125(2) 0.00929(5)
Ir2 0.38557(2) 0.37475(2) 0.23604(2) 0.00968(5)
N1 0.6950(4) 0.3383(5) 0.3082(3) 0.0112(11)
N2 0.2273(4) 0.2988(6) 0.1853(3) 0.0131(10)
O1 0.5114(3) 0.5857(5) 0.4076(2) 0.0132(9)
O2 0.3470(3) 0.4958(5) 0.3311(2) 0.0148(9)
O3 0.5742(3) 0.2491(5) 0.4147(2) 0.0149(9)
O4 0.4140(3) 0.1816(5) 0.3196(2) 0.0149(9)
O5 0.7881(4) 0.7513(6) 0.2180(3) 0.0360(14)
O6 0.9695(5) 0.6723(8) 0.2504(4) 0.0541(17)
O7 0.8941(4) 0.8798(6) 0.1508(3) 0.0457(16)
P1 0.75310(12) 0.55571(18) 0.44188(9) 0.0094(3)
P2 0.33301(12) 0.54958(19) 0.13456(9) 0.0112(3)
S1 0.87332(16) 0.7435(2) 0.18994(12) 0.0296(4)
Table A.15. Bond lengths (Å) for 3.3.
C1-O2 1.247(7) C1-O1 1.269(7)
C1-H1 0.9500 C2-O4 1.255(7)
C2-O3 1.264(7) C2-H2 0.9500
C3-N1 1.354(7) C3-C4 1.367(8)
C3-H3 0.9500 C4-C5 1.405(9)
C4-H4 0.9500 C5-C6 1.366(9)
C5-H5 0.9500 C6-C7 1.389(8)
C6-H6 0.9500 C7-N1 1.368(7)
C7-C8 1.492(8) C8-P1 1.840(6)
C8-H8A 0.9900 C8-H8B 0.9900
C9-C12 1.535(8) C9-C11 1.545(8)
C9-C10 1.554(8) C9-P1 1.876(6)
C10-H10A 0.9800 C10-H10B 0.9800
C10-H10C 0.9800 C11-H11A 0.9800
C11-H11B 0.9800 C11-H11C 0.9800
C12-H12A 0.9800 C12-H12B 0.9800
C12-H12C 0.9800 C13-C15 1.537(8)
C13-H13A 0.9800 C13-H13B 0.9800
C13-H13C 0.9800 C14-C15 1.541(8)
C14-H14A 0.9800 C14-H14B 0.9800
C14-H14C 0.9800 C15-C16 1.538(8)
218
C15-P1 1.880(6) C16-H16A 0.9800
C16-H16B 0.9800 C16-H16C 0.9800
C17-N2 1.355(8) C17-C18 1.383(8)
C17-H17 0.9500 C18-C19 1.394(9)
C18-H18 0.9500 C19-C20 1.374(9)
C19-H19 0.9500 C20-C21 1.406(8)
C20-H20 0.9500 C21-N2 1.355(7)
C21-C22 1.493(8) C22-P2 1.845(6)
C22-H22A 0.9900 C22-H22B 0.9900
C23-C24 1.528(9) C23-C26 1.531(9)
C23-C25 1.554(8) C23-P2 1.897(6)
C24-H24A 0.9800 C24-H24B 0.9800
C24-H24C 0.9800 C25-H25A 0.9800
C25-H25B 0.9800 C25-H25C 0.9800
C26-H26A 0.9800 C26-H26B 0.9800
C26-H26C 0.9800 C27-C29 1.534(8)
C27-C28 1.542(9) C27-C30 1.550(8)
C27-P2 1.878(6) C28-H28A 0.9800
C28-H28B 0.9800 C28-H28C 0.9800
C29-H29A 0.9800 C29-H29B 0.9800
C29-H29C 0.9800 C30-H30A 0.9800
C30-H30B 0.9800 C30-H30C 0.9800
C31-F1 1.318(8) C31-F3 1.343(8)
C31-F2 1.368(8) C31-S1 1.803(7)
Ir1-N1 2.033(5) Ir1-O1 2.082(4)
Ir1-O3 2.219(4) Ir1-P1 2.2514(15)
Ir1-Ir2 2.9433(4) Ir1-H31 1.53(6)
Ir1-H33 1.60(3) Ir2-N2 2.095(5)
Ir2-O4 2.141(4) Ir2-O2 2.188(4)
Ir2-P2 2.2274(15) Ir2-H32 1.45(6)
Ir2-H33 1.60(3) O5-S1 1.416(5)
O6-S1 1.473(6) O7-S1 1.426(5)
Table A.16. Bond angles (°) for 3.3.
O2-C1-O1 128.4(5) O2-C1-H1 115.8
O1-C1-H1 115.8 O4-C2-O3 128.5(6)
O4-C2-H2 115.8 O3-C2-H2 115.8
N1-C3-C4 123.0(6) N1-C3-H3 118.5
C4-C3-H3 118.5 C3-C4-C5 118.8(6)
C3-C4-H4 120.6 C5-C4-H4 120.6
C6-C5-C4 118.5(6) C6-C5-H5 120.8
C4-C5-H5 120.8 C5-C6-C7 120.9(6)
C5-C6-H6 119.6 C7-C6-H6 119.6
N1-C7-C6 120.4(6) N1-C7-C8 117.4(5)
C6-C7-C8 122.2(5) C7-C8-P1 109.8(4)
C7-C8-H8A 109.7 P1-C8-H8A 109.7
C7-C8-H8B 109.7 P1-C8-H8B 109.7
219
H8A-C8-H8B 108.2 C12-C9-C11 109.8(5)
C12-C9-C10 108.5(5) C11-C9-C10 107.3(5)
C12-C9-P1 115.7(4) C11-C9-P1 108.6(4)
C10-C9-P1 106.6(4) C9-C10-H10A 109.5
C9-C10-H10B 109.5 H10A-C10-H10B 109.5
C9-C10-H10C 109.5 H10A-C10-H10C 109.5
H10B-C10-H10C 109.5 C9-C11-H11A 109.5
C9-C11-H11B 109.5 H11A-C11-H11B 109.5
C9-C11-H11C 109.5 H11A-C11-H11C 109.5
H11B-C11-H11C 109.5 C9-C12-H12A 109.5
C9-C12-H12B 109.5 H12A-C12-H12B 109.5
C9-C12-H12C 109.5 H12A-C12-H12C 109.5
H12B-C12-H12C 109.5 C15-C13-H13A 109.5
C15-C13-H13B 109.5 H13A-C13-H13B 109.5
C15-C13-H13C 109.5 H13A-C13-H13C 109.5
H13B-C13-H13C 109.5 C15-C14-H14A 109.5
C15-C14-H14B 109.5 H14A-C14-H14B 109.5
C15-C14-H14C 109.5 H14A-C14-H14C 109.5
H14B-C14-H14C 109.5 C13-C15-C16 108.0(5)
C13-C15-C14 110.0(5) C16-C15-C14 107.2(5)
C13-C15-P1 111.1(4) C16-C15-P1 109.2(4)
C14-C15-P1 111.2(4) C15-C16-H16A 109.5
C15-C16-H16B 109.5 H16A-C16-H16B 109.5
C15-C16-H16C 109.5 H16A-C16-H16C 109.5
H16B-C16-H16C 109.5 N2-C17-C18 122.3(6)
N2-C17-H17 118.8 C18-C17-H17 118.8
C17-C18-C19 119.0(6) C17-C18-H18 120.5
C19-C18-H18 120.5 C20-C19-C18 118.7(6)
C20-C19-H19 120.6 C18-C19-H19 120.6
C19-C20-C21 120.4(6) C19-C20-H20 119.8
C21-C20-H20 119.8 N2-C21-C20 120.3(5)
N2-C21-C22 117.8(5) C20-C21-C22 121.9(5)
C21-C22-P2 110.9(4) C21-C22-H22A 109.5
P2-C22-H22A 109.5 C21-C22-H22B 109.5
P2-C22-H22B 109.5 H22A-C22-H22B 108.1
C24-C23-C26 108.2(5) C24-C23-C25 107.0(5)
C26-C23-C25 110.1(5) C24-C23-P2 109.1(4)
C26-C23-P2 110.7(4) C25-C23-P2 111.6(4)
C23-C24-H24A 109.5 C23-C24-H24B 109.5
H24A-C24-H24B 109.5 C23-C24-H24C 109.5
H24A-C24-H24C 109.5 H24B-C24-H24C 109.5
C23-C25-H25A 109.5 C23-C25-H25B 109.5
H25A-C25-H25B 109.5 C23-C25-H25C 109.5
H25A-C25-H25C 109.5 H25B-C25-H25C 109.5
C23-C26-H26A 109.5 C23-C26-H26B 109.5
H26A-C26-H26B 109.5 C23-C26-H26C 109.5
H26A-C26-H26C 109.5 H26B-C26-H26C 109.5
220
C29-C27-C28 107.6(5) C29-C27-C30 108.2(5)
C28-C27-C30 109.3(5) C29-C27-P2 114.4(4)
C28-C27-P2 107.2(4) C30-C27-P2 110.0(4)
C27-C28-H28A 109.5 C27-C28-H28B 109.5
H28A-C28-H28B 109.5 C27-C28-H28C 109.5
H28A-C28-H28C 109.5 H28B-C28-H28C 109.5
C27-C29-H29A 109.5 C27-C29-H29B 109.5
H29A-C29-H29B 109.5 C27-C29-H29C 109.5
H29A-C29-H29C 109.5 H29B-C29-H29C 109.5
C27-C30-H30A 109.5 C27-C30-H30B 109.5
H30A-C30-H30B 109.5 C27-C30-H30C 109.5
H30A-C30-H30C 109.5 H30B-C30-H30C 109.5
F1-C31-F3 107.6(6) F1-C31-F2 106.6(6)
F3-C31-F2 106.1(6) F1-C31-S1 114.1(5)
F3-C31-S1 112.7(5) F2-C31-S1 109.3(5)
N1-Ir1-O1 173.98(17) N1-Ir1-O3 89.94(17)
O1-Ir1-O3 87.23(16) N1-Ir1-P1 83.68(14)
O1-Ir1-P1 91.68(12) O3-Ir1-P1 101.61(11)
N1-Ir1-Ir2 102.20(13) O1-Ir1-Ir2 82.63(11)
O3-Ir1-Ir2 81.28(10) P1-Ir1-Ir2 173.53(4)
N1-Ir1-H31 90(2) O1-Ir1-H31 94(2)
O3-Ir1-H31 172(2) P1-Ir1-H31 86(2)
Ir2-Ir1-H31 91(2) N1-Ir1-H33 83.8(18)
O1-Ir1-H33 101.8(18) O3-Ir1-H33 94.9(19)
P1-Ir1-H33 159.2(18) Ir2-Ir1-H33 23.0(18)
H31-Ir1-H33 78(3) N2-Ir2-O4 87.28(17)
N2-Ir2-O2 88.50(16) O4-Ir2-O2 82.26(16)
N2-Ir2-P2 83.72(14) O4-Ir2-P2 169.94(12)
O2-Ir2-P2 101.93(11) N2-Ir2-Ir1 163.49(13)
O4-Ir2-Ir1 80.79(11) O2-Ir2-Ir1 78.67(10)
P2-Ir2-Ir1 108.91(4) N2-Ir2-H32 90(2)
O4-Ir2-H32 89(2) O2-Ir2-H32 171(2)
P2-Ir2-H32 87(2) Ir1-Ir2-H32 101(2)
N2-Ir2-H33 172.1(18) O4-Ir2-H33 93.5(19)
O2-Ir2-H33 99.4(18) P2-Ir2-H33 94.8(18)
Ir1-Ir2-H33 23.1(18) H32-Ir2-H33 82(3)
C3-N1-C7 118.3(5) C3-N1-Ir1 121.3(4)
C7-N1-Ir1 120.3(4) C17-N2-C21 119.2(5)
C17-N2-Ir2 121.7(4) C21-N2-Ir2 119.1(4)
C1-O1-Ir1 124.1(4) C1-O2-Ir2 124.8(4)
C2-O3-Ir1 122.3(4) C2-O4-Ir2 127.0(4)
C8-P1-C9 106.6(3) C8-P1-C15 104.0(3)
C9-P1-C15 111.2(3) C8-P1-Ir1 98.48(19)
C9-P1-Ir1 117.1(2) C15-P1-Ir1 117.0(2)
C22-P2-C27 105.0(3) C22-P2-C23 104.5(3)
C27-P2-C23 110.9(3) C22-P2-Ir2 99.3(2)
C27-P2-Ir2 116.2(2) C23-P2-Ir2 118.5(2)
221
O5-S1-O7 117.6(3) O5-S1-O6 112.5(4)
O7-S1-O6 113.8(4) O5-S1-C31 105.0(3)
O7-S1-C31 103.6(3) O6-S1-C31 102.1(4)
Table A.17. Anisotropic atomic displacement parameters (Å
2
) for 3.3.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.012(3) 0.013(3) 0.011(3) -0.002(2) 0.006(2) 0.002(2)
C2 0.015(3) 0.011(3) 0.017(3) 0.000(2) 0.008(3) 0.003(2)
C3 0.015(3) 0.015(3) 0.012(3) 0.001(2) 0.001(3) -0.001(3)
C4 0.026(4) 0.013(3) 0.009(3) 0.001(3) 0.006(3) 0.008(3)
C5 0.025(4) 0.016(3) 0.014(3) 0.002(3) 0.009(3) 0.008(3)
C6 0.018(3) 0.016(3) 0.016(3) 0.001(3) 0.007(3) 0.006(3)
C7 0.013(3) 0.011(3) 0.009(3) 0.003(3) 0.002(2) 0.002(3)
C8 0.014(3) 0.013(3) 0.009(3) -0.001(2) 0.003(2) -0.001(2)
C9 0.015(3) 0.009(3) 0.014(3) 0.000(2) 0.004(2) 0.002(3)
C10 0.019(3) 0.012(3) 0.015(3) 0.002(3) 0.004(3) 0.001(3)
C11 0.018(3) 0.012(3) 0.012(3) -0.002(2) 0.005(2) -0.004(2)
C12 0.014(3) 0.018(3) 0.016(3) -0.001(2) 0.002(3) 0.000(2)
C13 0.025(4) 0.012(3) 0.023(3) -0.003(3) 0.014(3) 0.001(3)
C14 0.016(3) 0.011(3) 0.023(3) -0.004(2) 0.007(3) -0.004(2)
C15 0.018(3) 0.013(3) 0.018(3) 0.000(3) 0.011(3) 0.000(3)
C16 0.023(3) 0.012(3) 0.023(3) 0.004(3) 0.009(3) 0.000(3)
C17 0.016(3) 0.015(3) 0.013(3) -0.002(2) 0.005(3) -0.001(2)
C18 0.015(3) 0.022(3) 0.021(3) -0.002(3) 0.010(3) -0.001(3)
C19 0.012(3) 0.026(4) 0.018(3) -0.004(3) 0.002(3) -0.003(3)
C20 0.014(3) 0.018(3) 0.015(3) -0.003(3) -0.002(3) -0.001(3)
C21 0.018(3) 0.010(3) 0.015(3) -0.003(2) 0.006(3) 0.002(2)
C22 0.017(3) 0.017(3) 0.012(3) 0.002(3) 0.002(2) 0.001(3)
C23 0.018(3) 0.022(3) 0.014(3) 0.002(3) 0.007(3) -0.004(3)
C24 0.029(4) 0.033(4) 0.016(3) -0.001(3) 0.016(3) 0.001(3)
C25 0.024(4) 0.032(4) 0.012(3) 0.002(3) 0.005(3) -0.005(3)
C26 0.019(4) 0.031(4) 0.016(3) 0.007(3) 0.005(3) -0.002(3)
C27 0.020(3) 0.012(3) 0.012(3) 0.001(2) 0.003(3) 0.005(3)
C28 0.015(3) 0.019(3) 0.020(3) 0.004(3) 0.003(3) 0.005(3)
C29 0.027(4) 0.016(3) 0.020(3) 0.006(3) 0.002(3) 0.005(3)
C30 0.022(3) 0.013(3) 0.017(3) -0.003(2) 0.006(3) -0.002(2)
C31 0.042(5) 0.019(4) 0.031(4) -0.002(3) 0.017(4) -0.002(3)
F1 0.080(3) 0.0134(19) 0.027(2) 0.001(2) 0.014(2) -0.009(2)
F2 0.033(3) 0.053(3) 0.029(2) 0.008(2) -0.002(2) -0.004(2)
F3 0.043(3) 0.038(3) 0.041(3) -0.016(2) 0.026(2) 0.001(2)
Ir1 0.00903(11) 0.00861(10) 0.00966(11) -0.00047(9) 0.00278(8) 0.00053(10)
Ir2 0.00962(11) 0.00965(11) 0.00843(10) -0.00005(10) 0.00181(8) 0.00039(10)
N1 0.014(3) 0.010(3) 0.007(2) 0.0012(18) 0.001(2) 0.0030(19)
N2 0.014(3) 0.011(2) 0.011(2) -0.003(2) 0.001(2) 0.003(2)
O1 0.014(2) 0.014(2) 0.012(2) -0.0015(17) 0.0039(18) 0.0025(17)
O2 0.013(2) 0.017(2) 0.014(2) -0.0025(17) 0.0052(17) -0.0014(17)
O3 0.012(2) 0.015(2) 0.014(2) 0.0013(17) 0.0006(18) -0.0036(18)
222
O4 0.013(2) 0.016(2) 0.012(2) 0.0036(18) 0.0006(19) -0.0047(18)
O5 0.054(4) 0.029(3) 0.040(3) 0.000(2) 0.035(3) 0.001(3)
O6 0.031(3) 0.079(5) 0.041(4) -0.018(3) 0.000(3) 0.002(3)
O7 0.085(5) 0.023(3) 0.049(3) -0.017(3) 0.047(3) -0.024(4)
P1 0.0101(7) 0.0076(7) 0.0107(7) -0.0016(6) 0.0041(6) -0.0006(6)
P2 0.0107(8) 0.0127(8) 0.0089(7) 0.0014(6) 0.0022(6) 0.0012(6)
S1 0.0379(11) 0.0221(10) 0.0386(11) -0.0151(8) 0.0256(9) -0.0098(8)
Table A.18. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 3.3.
x/a y/b z/c U(eq)
H1 0.384620 0.614855 0.426882 0.014
H2 0.490122 0.073535 0.416508 0.016
H3 0.587817 0.176877 0.248213 0.018
H4 0.696222 0.024606 0.203464 0.019
H5 0.874644 0.105410 0.233553 0.021
H6 0.936814 0.328339 0.313386 0.020
H8A 833372 0.616328 0.347027 0.015
H8B 0.911678 0.508108 0.418786 0.015
H10A 0.888053 0.276130 0.488780 0.023
H10B 0.768743 0.228622 0.476453 0.023
H10C 0.862287 0.206136 0.563703 0.023
H11A 0.722735 0.533943 0.600444 0.021
H11B 0.762088 0.358022 0.628577 0.021
H11C 0.667069 0.388111 0.542871 0.021
H12A 0.908213 0.609201 0.621154 0.025
H12B 0.970466 0.523646 0.571285 0.025
H12C 0.951982 0.433560 0.644676 0.025
H13A 0.650442 0.775657 0.516596 0.028
H13B 0.721554 0.932052 0.535339 0.028
H13C 0.770055 0.771166 0.581566 0.028
H14A 0.899749 0.812545 0.437467 0.026
H14B 0.924210 0.780016 0.532145 0.026
H14C 0.879223 0.947882 0.493137 0.026
H16A 0.714465 0.832527 0.338343 0.029
H16B 0.698787 0.974579 0.392550 0.029
H16C 0.617505 0.829450 0.369447 0.029
H17 0.227457 0.174034 0.281342 0.018
H18 0.054176 0.080614 0.223848 0.022
H19 -0.052858 0.156163 0.089521 0.023
H20 0.018673 0.322580 0.017935 0.021
H22A 0.164137 0.520784 0.028874 0.019
H22B 0.239425 0.376822 0.026322 0.019
H24A 0.529528 0.407322 0.127899 0.036
H24B 0.522024 0.448383 0.037316 0.036
H24C 0.430070 0.347450 0.050802 0.036
H25A 0.313802 0.725286 -0.017246 0.035
H25B 0.306874 0.543117 -0.042284 0.035
223
H25C 0.403200 0.649228 -0.044970 0.035
H26A 0.468039 0.817191 0.104676 0.034
H26B 0.558589 0.712837 0.091197 0.034
H26C 0.535495 0.694785 0.173459 0.034
H28A 0.207698 0.629939 0.229235 0.029
H28B 0.128703 0.644800 0.135903 0.029
H28C 0.153826 0.795952 0.194343 0.029
H29A 0.297746 0.891969 0.070531 0.034
H29B 0.201599 0.942901 0.097273 0.034
H29C 0.187544 0.797913 0.036059 0.034
H30A 0.417990 0.871182 0.209157 0.027
H30B 0.397954 0.752922 0.272711 0.027
H30C 0.330953 0.912779 0.247449 0.027
H31 0.603(5) 0.603(7) 0.298(4) 0.011
H32 0.412(4) 0.273(7) 0.181(4) 0.012
H33 0.509(2) 0.419(6) 0.265(3) 0.012
224
Crystal Structure of 3.5
A specimen of C
32
H
51
Cl
2
F
3
Ir
2
N
2
O
5
P
2
S, approximate dimensions 0.030 mm x 0.060 mm x 0.140 mm,
was used for the X-ray crystallographic analysis. The X-ray intensity data were measured on a Bruker APEX
DUO system equipped with a fine-focus tube (MoKα , λ = 0.71073 Å) and a TRIUMPH curved-crystal
monochromator.
The total exposure time was 3.50 hours. The frames were integrated with the Bruker SAINT software
package using a SAINT V8.40A (Bruker AXS, 2013) algorithm. The integration of the data using a monoclinic
unit cell yielded a total of 100068 reflections to a maximum θ angle of 30.56 (0.70 Å resolution), of which
12322 were independent (average redundancy 8.121, completeness = 99.4%, R
int
= 7.06%, R
sig
= 4.33%)
and 9871 (80.11%) were greater than 2σ(F
2
). The final cell constants of a = 14.7885(16) Å, b = 17.1958(19)
Å, c = 15.9928(18) Å, β = 96.222(2), volume = 4043.0(8) Å
3
, are based upon the refinement of the XYZ-
centroids of 9022 reflections above 20 σ(I) with 5.121 < 2θ < 60.94. Data were corrected for absorption
effects using the multi-scan method (SADABS). The ratio of minimum to maximum apparent transmission
225
was 0.762. The calculated minimum and maximum transmission coefficients (based on crystal size) are
0.4450 and 0.8200.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/c 1, with Z = 4 for the formula unit, C
32
H
51
Cl
2
F
3
Ir
2
N
2
O
5
P
2
S. The final anisotropic full-matrix
least-squares refinement on F
2
with 458 variables converged at R1 = 2.84%, for the observed data and
wR2 = 5.38% for all data. The goodness-of-fit was 1.027. The largest peak in the final difference electron
density synthesis was 1.414 e
-
/Å
3
and the largest hole was -0.995 e
-
/Å
3
with an RMS deviation of 0.169 e
-
/Å
3
. On the basis of the final model, the calculated density was 1.889 g/cm
3
and F(000), 2232 e
-
.
Table A.19. Sample and crystal data for 3.5
Chemical formula C
32
H
51
Cl
2
F
3
Ir
2
N
2
O
5
P
2
S
Formula weight 1150.05 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.030 x 0.060 x 0.140 mm
Crystal system monoclinic
Space group P 1 21/c 1
Unit cell dimensions a = 14.7885(16) Å α = 90°
b = 17.1958(19) Å β = 96.222(2)°
c = 15.9928(18) Å γ = 90°
Volume 4043.0(8) Å
3
Z 4
Density (calculated) 1.889 g/cm
3
Absorption coefficient 6.892 mm
-1
F(000) 2232
Table A.20. Data collection and structure refinement for 3.5.
Diffractometer Bruker APEX DUO
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.74 to 30.56°
Index ranges -20<=h<=21, -24<=k<=24, -22<=l<=22
Reflections collected 100068
Independent reflections 12322 [R(int) = 0.0706]
Coverage of independent reflections 99.4%
Absorption correction multi-scan
Max. and min. transmission 0.8200 and 0.4450
226
Structure solution technique direct methods
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXTL XL 2018/3 (Bruker AXS, 2018)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 12322 / 0 / 458
Goodness-of-fit on F
2
1.027
Δ/σ
max
0.003
Final R indices 9871 data; I>2σ(I) R1 = 0.0284, wR2 = 0.0494
all data R1 = 0.0463, wR2 = 0.0538
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0143P)
2
+7.3865P]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 1.414 and -0.995 eÅ
-3
R.M.S. deviation from mean 0.169 eÅ
-3
Table A.21. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for
3.5.
x/a y/b z/c U(eq)
C1 0.7874(2) 0.1316(2) 0.5395(2) 0.0178(7)
C2 0.6307(2) 0.1518(2) 0.3550(2) 0.0188(7)
C3 0.8351(2) 0.88721(19) 0.4531(2) 0.0142(7)
C4 0.8114(2) 0.91184(19) 0.3637(2) 0.0144(7)
C5 0.8064(2) 0.8582(2) 0.2988(2) 0.0188(7)
C6 0.7846(3) 0.8816(2) 0.2163(2) 0.0260(9)
C7 0.7681(3) 0.9594(2) 0.2002(2) 0.0285(9)
C8 0.7742(3) 0.0111(2) 0.2663(2) 0.0208(8)
C9 0.6704(2) 0.9262(2) 0.5372(2) 0.0156(7)
C10 0.6232(2) 0.9109(2) 0.4480(2) 0.0204(8)
C11 0.6202(2) 0.9941(2) 0.5745(2) 0.0197(7)
C12 0.6614(3) 0.8530(2) 0.5902(2) 0.0215(8)
C13 0.8669(2) 0.9461(2) 0.6255(2) 0.0158(7)
C14 0.9581(3) 0.9852(2) 0.6132(2) 0.0236(8)
C15 0.8275(3) 0.9870(2) 0.6989(2) 0.0204(8)
C16 0.8858(3) 0.8600(2) 0.6479(2) 0.0232(8)
C17 0.7390(2) 0.39768(18) 0.3658(2) 0.0142(7)
C18 0.8318(2) 0.36783(19) 0.3986(2) 0.0147(7)
C19 0.9044(2) 0.4185(2) 0.4166(2) 0.0189(7)
C20 0.9888(3) 0.3897(2) 0.4453(3) 0.0237(8)
C21 0.9995(3) 0.3102(2) 0.4573(3) 0.0263(9)
C22 0.9249(3) 0.2629(2) 0.4390(2) 0.0223(8)
C23 0.5570(2) 0.34886(19) 0.2968(2) 0.0136(6)
C24 0.4682(2) 0.3076(2) 0.3126(2) 0.0194(7)
227
C25 0.5388(3) 0.4364(2) 0.2849(2) 0.0192(7)
C26 0.5886(3) 0.3166(2) 0.2156(2) 0.0200(8)
C27 0.6164(2) 0.34935(19) 0.4901(2) 0.0127(6)
C28 0.5592(2) 0.2817(2) 0.5188(2) 0.0175(7)
C29 0.5636(2) 0.4257(2) 0.4948(2) 0.0182(7)
C30 0.7046(2) 0.3552(2) 0.5504(2) 0.0197(7)
Ir1 0.79327(2) 0.06799(2) 0.44948(2) 0.01162(3)
Ir2 0.72903(2) 0.21430(2) 0.38225(2) 0.01156(3)
N1 0.7951(2) 0.98881(16) 0.34772(17) 0.0148(6)
N2 0.84175(19) 0.29001(17) 0.40903(19) 0.0169(6)
O1 0.7820(2) 0.16911(15) 0.59898(17) 0.0266(6)
O2 0.56874(19) 0.11211(15) 0.33666(19) 0.0304(7)
P1 0.79013(6) 0.95754(5) 0.52538(5) 0.01112(16)
P2 0.64995(6) 0.32717(5) 0.38302(5) 0.01053(16)
C31 0.6847(3) 0.6551(2) 0.3719(2) 0.0288(9)
F1 0.6333(2) 0.59727(16) 0.34030(17) 0.0576(9)
F2 0.6356(2) 0.71982(14) 0.36774(16) 0.0425(7)
F3 0.7501(2) 0.66503(17) 0.31976(18) 0.0615(9)
O3 0.65813(19) 0.62435(18) 0.52353(18) 0.0326(7)
O4 0.7893(2) 0.56646(16) 0.4703(2) 0.0345(7)
O5 0.78679(18) 0.70527(15) 0.49997(18) 0.0274(6)
S1 0.73585(6) 0.63550(5) 0.47847(6) 0.01765(18)
C32 0.9013(3) 0.2899(3) 0.7172(3) 0.0377(11)
Cl1 0.93252(9) 0.36751(10) 0.65565(8) 0.0569(4)
Cl2 0.97569(9) 0.21009(9) 0.71598(10) 0.0639(4)
Table A.22. Bond lengths (Å) for 3.5.
C1-O1 1.160(4) C1-Ir1 1.817(4)
C2-O2 1.154(4) C2-Ir2 1.823(4)
C3-C4 1.496(5) C3-P1 1.847(3)
C3-H3A 0.99 C3-H3AB 0.99
C4-N1 1.365(4) C4-C5 1.384(5)
C5-C6 1.383(5) C5-H5 0.95
C6-C7 1.378(5) C6-H6 0.95
C7-C8 1.377(5) C7-H7 0.95
C8-N1 1.361(4) C8-H8 0.95
C9-C12 1.531(5) C9-C11 1.538(5)
C9-C10 1.541(5) C9-P1 1.880(3)
C10-H10A 0.98 C10-H10B 0.98
C10-H10C 0.98 C11-H11A 0.98
C11-H11B 0.98 C11-H11C 0.98
C12-H12A 0.98 C12-H12B 0.98
228
C12-H12C 0.98 C13-C15 1.537(5)
C13-C14 1.539(5) C13-C16 1.541(5)
C13-P1 1.871(3) C14-H14A 0.98
C14-H14B 0.98 C14-H14C 0.98
C15-H15A 0.98 C15-H15B 0.98
C15-H15C 0.98 C16-H16A 0.98
C16-H16B 0.98 C16-H16C 0.98
C17-C18 1.506(5) C17-P2 1.832(3)
C17-H17A 0.99 C17-H17B 0.99
C18-N2 1.355(4) C18-C19 1.388(5)
C19-C20 1.375(5) C19-H19 0.95
C20-C21 1.387(5) C20-H20 0.95
C21-C22 1.377(5) C21-H21 0.95
C22-N2 1.354(4) C22-H22 0.95
C23-C26 1.531(5) C23-C24 1.537(5)
C23-C25 1.537(5) C23-P2 1.875(3)
C24-H24A 0.98 C24-H24B 0.98
C24-H24C 0.98 C25-H25A 0.98
C25-H25B 0.98 C25-H25C 0.98
C26-H26A 0.98 C26-H26B 0.98
C26-H26C 0.98 C27-C29 1.533(5)
C27-C28 1.537(5) C27-C30 1.540(5)
C27-P2 1.873(3) C28-H28A 0.98
C28-H28B 0.98 C28-H28C 0.98
C29-H29A 0.98 C29-H29B 0.98
C29-H29C 0.98 C30-H30A 0.98
C30-H30B 0.98 C30-H30C 0.98
Ir1-N1 2.124(3) Ir1-P1 2.2571(9)
Ir1-Ir2 2.8579(3) Ir1-H1 1.79(4)
Ir2-N2 2.122(3) Ir2-P2 2.2667(9)
Ir2-H1 1.80(4) C31-F1 1.319(5)
C31-F2 1.327(5) C31-F3 1.354(5)
C31-S1 1.820(4) O3-S1 1.434(3)
O4-S1 1.440(3) O5-S1 1.438(3)
C32-Cl1 1.750(5) C32-Cl2 1.761(5)
C32-H32A 0.99 C32-H32B 0.99
Table A.23. Bond angles (°) for 3.5.
O1-C1-Ir1 176.6(3) O2-C2-Ir2 179.0(4)
C4-C3-P1 110.5(2) C4-C3-H3A 109.6
P1-C3-H3A 109.6 C4-C3-H3AB 109.6
229
P1-C3-H3AB 109.6 H3A-C3-H3AB 108.1
N1-C4-C5 120.8(3) N1-C4-C3 118.1(3)
C5-C4-C3 121.0(3) C6-C5-C4 120.6(3)
C6-C5-H5 119.7 C4-C5-H5 119.7
C7-C6-C5 118.6(3) C7-C6-H6 120.7
C5-C6-H6 120.7 C8-C7-C6 119.2(4)
C8-C7-H7 120.4 C6-C7-H7 120.4
N1-C8-C7 122.8(3) N1-C8-H8 118.6
C7-C8-H8 118.6 C12-C9-C11 109.6(3)
C12-C9-C10 108.3(3) C11-C9-C10 107.4(3)
C12-C9-P1 115.5(2) C11-C9-P1 108.7(2)
C10-C9-P1 107.0(2) C9-C10-H10A 109.5
C9-C10-H10B 109.5 H10A-C10-H10B 109.5
C9-C10-H10C 109.5 H10A-C10-H10C 109.5
H10B-C10-H10C 109.5 C9-C11-H11A 109.5
C9-C11-H11B 109.5 H11A-C11-H11B 109.5
C9-C11-H11C 109.5 H11A-C11-H11C 109.5
H11B-C11-H11C 109.5 C9-C12-H12A 109.5
C9-C12-H12B 109.5 H12A-C12-H12B 109.5
C9-C12-H12C 109.5 H12A-C12-H12C 109.5
H12B-C12-H12C 109.5 C15-C13-C14 107.9(3)
C15-C13-C16 109.7(3) C14-C13-C16 108.1(3)
C15-C13-P1 111.1(2) C14-C13-P1 107.7(2)
C16-C13-P1 112.2(2) C13-C14-H14A 109.5
C13-C14-H14B 109.5 H14A-C14-H14B 109.5
C13-C14-H14C 109.5 H14A-C14-H14C 109.5
H14B-C14-H14C 109.5 C13-C15-H15A 109.5
C13-C15-H15B 109.5 H15A-C15-H15B 109.5
C13-C15-H15C 109.5 H15A-C15-H15C 109.5
H15B-C15-H15C 109.5 C13-C16-H16A 109.5
C13-C16-H16B 109.5 H16A-C16-H16B 109.5
C13-C16-H16C 109.5 H16A-C16-H16C 109.5
H16B-C16-H16C 109.5 C18-C17-P2 111.4(2)
C18-C17-H17A 109.3 P2-C17-H17A 109.3
C18-C17-H17B 109.3 P2-C17-H17B 109.3
H17A-C17-H17B 108.0 N2-C18-C19 121.6(3)
N2-C18-C17 117.5(3) C19-C18-C17 120.9(3)
C20-C19-C18 119.7(3) C20-C19-H19 120.1
C18-C19-H19 120.1 C19-C20-C21 119.2(3)
C19-C20-H20 120.4 C21-C20-H20 120.4
C22-C21-C20 118.4(4) C22-C21-H21 120.8
C20-C21-H21 120.8 N2-C22-C21 123.2(3)
230
N2-C22-H22 118.4 C21-C22-H22 118.4
C26-C23-C24 108.5(3) C26-C23-C25 108.3(3)
C24-C23-C25 109.4(3) C26-C23-P2 106.5(2)
C24-C23-P2 111.0(2) C25-C23-P2 113.0(2)
C23-C24-H24A 109.5 C23-C24-H24B 109.5
H24A-C24-H24B 109.5 C23-C24-H24C 109.5
H24A-C24-H24C 109.5 H24B-C24-H24C 109.5
C23-C25-H25A 109.5 C23-C25-H25B 109.5
H25A-C25-H25B 109.5 C23-C25-H25C 109.5
H25A-C25-H25C 109.5 H25B-C25-H25C 109.5
C23-C26-H26A 109.5 C23-C26-H26B 109.5
H26A-C26-H26B 109.5 C23-C26-H26C 109.5
H26A-C26-H26C 109.5 H26B-C26-H26C 109.5
C29-C27-C28 109.5(3) C29-C27-C30 108.4(3)
C28-C27-C30 108.6(3) C29-C27-P2 114.0(2)
C28-C27-P2 109.2(2) C30-C27-P2 107.2(2)
C27-C28-H28A 109.5 C27-C28-H28B 109.5
H28A-C28-H28B 109.5 C27-C28-H28C 109.5
H28A-C28-H28C 109.5 H28B-C28-H28C 109.5
C27-C29-H29A 109.5 C27-C29-H29B 109.5
H29A-C29-H29B 109.5 C27-C29-H29C 109.5
H29A-C29-H29C 109.5 H29B-C29-H29C 109.5
C27-C30-H30A 109.5 C27-C30-H30B 109.5
H30A-C30-H30B 109.5 C27-C30-H30C 109.5
H30A-C30-H30C 109.5 H30B-C30-H30C 109.5
C1-Ir1-N1 176.55(13) C1-Ir1-P1 94.30(11)
N1-Ir1-P1 82.84(8) C1-Ir1-Ir2 74.08(11)
N1-Ir1-Ir2 107.89(8) P1-Ir1-Ir2 156.60(2)
C1-Ir1-H1 97.3(13) N1-Ir1-H1 85.9(13)
P1-Ir1-H1 165.3(13) Ir2-Ir1-H1 37.5(13)
C2-Ir2-N2 177.44(14) C2-Ir2-P2 96.16(11)
N2-Ir2-P2 82.42(8) C2-Ir2-Ir1 78.16(11)
N2-Ir2-Ir1 104.03(8) P2-Ir2-Ir1 154.48(2)
C2-Ir2-H1 97.6(13) N2-Ir2-H1 83.5(13)
P2-Ir2-H1 164.7(13) Ir1-Ir2-H1 37.3(13)
C8-N1-C4 118.0(3) C8-N1-Ir1 122.1(2)
C4-N1-Ir1 119.7(2) C22-N2-C18 117.8(3)
C22-N2-Ir2 121.6(2) C18-N2-Ir2 120.6(2)
C3-P1-C13 103.90(15) C3-P1-C9 106.41(16)
C13-P1-C9 112.01(16) C3-P1-Ir1 100.64(11)
C13-P1-Ir1 120.21(11) C9-P1-Ir1 111.70(11)
C17-P2-C27 105.58(15) C17-P2-C23 103.85(15)
231
C27-P2-C23 112.67(15) C17-P2-Ir2 100.73(11)
C27-P2-Ir2 111.55(11) C23-P2-Ir2 120.25(11)
F1-C31-F2 108.8(4) F1-C31-F3 106.3(3)
F2-C31-F3 106.7(3) F1-C31-S1 112.5(3)
F2-C31-S1 111.8(3) F3-C31-S1 110.4(3)
O3-S1-O5 114.76(18) O3-S1-O4 114.40(18)
O5-S1-O4 115.55(17) O3-S1-C31 102.79(19)
O5-S1-C31 102.88(18) O4-S1-C31 104.11(19)
Cl1-C32-Cl2 112.6(3) Cl1-C32-H32A 109.1
Cl2-C32-H32A 109.1 Cl1-C32-H32B 109.1
Cl2-C32-H32B 109.1 H32A-C32-H32B 107.8
Table A.24. Torsion angles (°) for 3.5.
P1-C3-C4-N1
24.4(4) P1-C3-C4-C5 -155.7(3)
N1-C4-C5-C6 0.0(5) C3-C4-C5-C6 -179.8(3)
C4-C5-C6-C7 0.0(6) C5-C6-C7-C8 0.3(6)
C6-C7-C8-N1 -0.7(6) P2-C17-C18-N2 20.9(4)
P2-C17-C18-C19 -159.5(3) N2-C18-C19-C20 0.4(5)
C17-C18-C19-C20 -179.1(3) C18-C19-C20-C21 -1.2(6)
C19-C20-C21-C22 0.7(6) C20-C21-C22-N2 0.7(6)
C7-C8-N1-C4 0.7(5) C7-C8-N1-Ir1 -174.8(3)
C5-C4-N1-C8 -0.4(5) C3-C4-N1-C8 179.5(3)
C5-C4-N1-Ir1 175.2(3) C3-C4-N1-Ir1 -4.9(4)
C21-C22-N2-C18 -1.5(6) C21-C22-N2-Ir2 -179.8(3)
C19-C18-N2-C22 0.9(5) C17-C18-N2-C22 -179.6(3)
C19-C18-N2-Ir2 179.3(3) C17-C18-N2-Ir2 -1.2(4)
C4-C3-P1-C13 -154.6(2) C4-C3-P1-C9 87.0(3)
C4-C3-P1-Ir1 -29.6(3) C15-C13-P1-C3 -167.5(2)
C14-C13-P1-C3 74.5(3) C16-C13-P1-C3 -44.3(3)
C15-C13-P1-C9 -53.0(3) C14-C13-P1-C9 -171.1(2)
C16-C13-P1-C9 70.1(3) C15-C13-P1-Ir1 81.1(3)
C14-C13-P1-Ir1 -36.9(3) C16-C13-P1-Ir1 -155.7(2)
C12-C9-P1-C3 72.9(3) C11-C9-P1-C3 -163.5(2)
C10-C9-P1-C3 -47.8(3) C12-C9-P1-C13 -40.0(3)
C11-C9-P1-C13 83.6(3) C10-C9-P1-C13 -160.7(2)
C12-C9-P1-Ir1 -178.2(2) C11-C9-P1-Ir1 -54.6(3)
C10-C9-P1-Ir1 61.1(2) C18-C17-P2-C27 88.4(3)
C18-C17-P2-C23 -152.8(2) C18-C17-P2-Ir2 -27.8(2)
C29-C27-P2-C17 70.8(3) C28-C27-P2-C17 -166.5(2)
C30-C27-P2-C17 -49.1(3) C29-C27-P2-C23 -41.9(3)
C28-C27-P2-C23 80.8(3) C30-C27-P2-C23 -161.8(2)
232
C29-C27-P2-Ir2 179.3(2) C28-C27-P2-Ir2 -58.0(2)
C30-C27-P2-Ir2 59.4(2) C26-C23-P2-C17 74.7(3)
C24-C23-P2-C17 -167.4(2) C25-C23-P2-C17 -44.2(3)
C26-C23-P2-C27 -171.6(2) C24-C23-P2-C27 -53.7(3)
C25-C23-P2-C27 69.6(3) C26-C23-P2-Ir2 -36.8(3)
C24-C23-P2-Ir2 81.1(2) C25-C23-P2-Ir2 -155.6(2)
F1-C31-S1-O3 -59.8(4) F2-C31-S1-O3 63.1(3)
F3-C31-S1-O3 -178.3(3) F1-C31-S1-O5 -179.3(3)
F2-C31-S1-O5 -56.4(3) F3-C31-S1-O5 62.2(3)
F1-C31-S1-O4 59.8(4) F2-C31-S1-O4 -177.3(3)
F3-C31-S1-O4 -58.7(3)
Table A.25. Anisotropic atomic displacement parameters (Å
2
) for 3.5.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.0198(18) 0.0116(16) 0.0219(18) 0.0029(14) 0.0013(15) -0.0001(14)
C2 0.0168(18) 0.0119(16) 0.027(2) 0.0003(14) 0.0019(15) 0.0066(14)
C3 0.0166(17) 0.0101(15) 0.0164(17) 0.0004(12) 0.0047(13) 0.0063(13)
C4 0.0143(16) 0.0145(16) 0.0150(16) 0.0000(13) 0.0047(13) -0.0001(13)
C5 0.0241(19) 0.0094(15) 0.0231(19) -0.0010(14) 0.0042(15) 0.0010(14)
C6 0.041(2) 0.0198(19) 0.0181(19) -0.0049(15) 0.0054(17) 0.0003(17)
C7 0.050(3) 0.0210(19) 0.0139(18) 0.0002(15) 0.0010(18) 0.0024(19)
C8 0.025(2) 0.0189(18) 0.0189(18) 0.0049(14) 0.0027(15) 0.0027(15)
C9 0.0129(16) 0.0142(16) 0.0204(17) -0.0008(14) 0.0054(13) 0.0016(13)
C10 0.0176(18) 0.0217(18) 0.0217(19) -0.0013(15) 0.0013(15) -0.0067(15)
C11 0.0151(17) 0.0199(18) 0.0246(19) -0.0039(15) 0.0048(15) 0.0021(14)
C12 0.0224(19) 0.0192(18) 0.0242(19) 0.0017(15) 0.0090(16) -0.0009(15)
C13 0.0151(17) 0.0194(17) 0.0126(16) 0.0009(13) 0.0003(13) 0.0016(14)
C14 0.0182(19) 0.029(2) 0.0222(19) 0.0005(16) -0.0024(15) 0.0003(16)
C15 0.0215(19) 0.0252(19) 0.0146(17) -0.0008(15) 0.0020(15) 0.0023(16)
C16 0.027(2) 0.0236(19) 0.0187(18) 0.0028(15) 0.0008(16) 0.0065(16)
C17 0.0132(16) 0.0080(14) 0.0212(18) 0.0011(13) 0.0014(14) -0.0008(12)
C18 0.0129(16) 0.0134(16) 0.0185(17) -0.0015(13) 0.0044(14) 0.0009(13)
C19 0.0183(18) 0.0139(16) 0.0252(19) -0.0042(14) 0.0046(15) -0.0021(14)
C20 0.0138(18) 0.0234(19) 0.034(2) -0.0094(17) 0.0030(16) -0.0060(15)
C21 0.0117(17) 0.023(2) 0.043(3) -0.0077(18) 0.0005(17) 0.0034(15)
C22 0.0181(18) 0.0166(17) 0.032(2) -0.0020(15) 0.0028(16) 0.0067(14)
C23 0.0137(16) 0.0130(15) 0.0133(16) -0.0007(13) -0.0021(13) 0.0014(13)
C24 0.0159(17) 0.0200(18) 0.0209(18) -0.0005(14) -0.0039(14) -0.0002(14)
C25 0.0221(18) 0.0167(17) 0.0177(17) 0.0018(14) -0.0033(14) 0.0031(15)
C26 0.028(2) 0.0191(18) 0.0122(16) -0.0015(14) -0.0010(15) 0.0031(15)
C27 0.0162(16) 0.0118(15) 0.0098(15) -0.0014(12) -0.0009(13) 0.0013(13)
C28 0.0225(18) 0.0173(17) 0.0133(16) 0.0039(14) 0.0044(14) -0.0023(15)
233
U
11
U
22
U
33
U
23
U
13
U
12
C29 0.0193(18) 0.0181(17) 0.0175(17) -0.0001(14) 0.0032(14) 0.0054(14)
C30 0.0200(18) 0.0230(18) 0.0145(16) -0.0045(15) -0.0046(14) 0.0078(15)
Ir1 0.01283(6) 0.00803(6) 0.01419(6) -0.00036(5) 0.00234(5) 0.00127(5)
Ir2 0.01194(6) 0.00784(6) 0.01507(6) -0.00050(5) 0.00226(5) 0.00100(5)
N1 0.0197(15) 0.0122(13) 0.0132(14) 0.0020(11) 0.0045(12) 0.0020(12)
N2 0.0136(14) 0.0136(14) 0.0239(16) -0.0030(12) 0.0033(12) 0.0017(12)
O1 0.0412(18) 0.0160(13) 0.0230(14) -0.0061(11) 0.0055(13) 0.0022(12)
O2 0.0212(15) 0.0177(14) 0.0514(19) -0.0046(13) -0.0009(13) -0.0040(11)
P1 0.0119(4) 0.0093(4) 0.0123(4) -0.0007(3) 0.0023(3) 0.0021(3)
P2 0.0106(4) 0.0088(4) 0.0122(4) -0.0002(3) 0.0015(3) 0.0000(3)
C31 0.044(3) 0.024(2) 0.0174(19) -0.0020(16) -0.0009(18) -0.0041(19)
F1 0.093(3) 0.0321(15) 0.0386(16) -0.0003(12) -0.0337(16) -0.0232(16)
F2 0.0638(19) 0.0237(13) 0.0358(15) 0.0068(11) -0.0136(13) 0.0081(13)
F3 0.107(3) 0.0476(18) 0.0370(17) -0.0072(14) 0.0396(18) -0.0135(18)
O3 0.0239(15) 0.0428(18) 0.0320(16) 0.0076(14) 0.0064(13) -0.0045(13)
O4 0.0305(16) 0.0165(14) 0.055(2) -0.0066(13) -0.0002(15) 0.0078(12)
O5 0.0198(14) 0.0190(14) 0.0418(17) -0.0076(12) -0.0037(12) -0.0034(11)
S1 0.0162(4) 0.0129(4) 0.0232(5) -0.0016(3) -0.0006(4) -0.0001(3)
C32 0.023(2) 0.038(3) 0.052(3) -0.012(2) 0.005(2) 0.0004(19)
Cl1 0.0410(7) 0.0929(11) 0.0357(7) 0.0189(7) -0.0006(6) 0.0025(7)
Cl2 0.0420(7) 0.0600(9) 0.0840(11) -0.0333(8) -0.0186(7) 0.0204(7)
Table A.26. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 3.5.
x/a y/b z/c U(eq)
H3A 0.9021 -0.1163 0.4655 0.017
H3AB 0.8092 -0.1649 0.4617 0.017
H5 0.8180 -0.1952 0.3110 0.023
H6 0.7811 -0.1551 0.1717 0.031
H7 0.7528 -0.0230 0.1442 0.034
H8 0.7634 0.0647 0.2545 0.025
H10A 0.6274 -0.0425 0.4134 0.031
H10B 0.5590 -0.1018 0.4512 0.031
H10C 0.6530 -0.1327 0.4227 0.031
H11A 0.6193 0.0390 0.5366 0.03
H11B 0.6517 0.0082 0.6295 0.03
H11C 0.5576 -0.0216 0.5811 0.03
H12A 0.5970 -0.1611 0.5889 0.032
H12B 0.6867 -0.1370 0.6484 0.032
H12C 0.6947 -0.1899 0.5672 0.032
H14A 0.9843 -0.0395 0.5661 0.035
H14B 1.0002 -0.0206 0.6646 0.035
234
x/a y/b z/c U(eq)
H14C 0.9481 0.0405 0.6011 0.035
H15A 0.8135 0.0412 0.6837 0.031
H15B 0.8721 -0.0145 0.7489 0.031
H15C 0.7717 -0.0396 0.7109 0.031
H16A 0.9133 -0.1654 0.6020 0.035
H16B 0.8285 -0.1661 0.6562 0.035
H16C 0.9275 -0.1433 0.6997 0.035
H17A 0.7373 0.4085 0.3049 0.017
H17B 0.7271 0.4470 0.3945 0.017
H19 0.8957 0.4729 0.4091 0.023
H20 1.0391 0.4238 0.4567 0.028
H21 1.0570 0.2890 0.4777 0.032
H22 0.9322 0.2085 0.4479 0.027
H24A 0.4234 0.3138 0.2633 0.029
H24B 0.4445 0.3306 0.3619 0.029
H24C 0.4802 0.2522 0.3228 0.029
H25A 0.5954 0.4628 0.2751 0.029
H25B 0.5162 0.4577 0.3355 0.029
H25C 0.4933 0.4445 0.2364 0.029
H26A 0.5431 0.3287 0.1682 0.03
H26B 0.5959 0.2601 0.2205 0.03
H26C 0.6469 0.3403 0.2062 0.03
H28A 0.5028 0.2772 0.4808 0.026
H28B 0.5444 0.2917 0.5761 0.026
H28C 0.5939 0.2332 0.5178 0.026
H29A 0.5983 0.4683 0.4731 0.027
H29B 0.5541 0.4363 0.5534 0.027
H29C 0.5045 0.4212 0.4608 0.027
H30A 0.7398 0.3072 0.5474 0.029
H30B 0.6895 0.3626 0.6080 0.029
H30C 0.7407 0.3994 0.5342 0.029
H32A 0.8389 0.2730 0.6963 0.045
H32B 0.9004 0.3079 0.7760 0.045
H1 0.816(3) 0.142(2) 0.375(2) 0.029(11)
235
Crystal Structure of 4.4
A green needle-like specimen of C
44
H
71
Cl
2
F
3
N
3
O
4
P
3
Ru
3
S, approximate dimensions 0.080 mm x 0.090
mm x 0.554 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured
on a Bruker APEX DUO system equipped with a fine-focus tube (MoKα , λ = 0.71073 Å) and a TRIUMPH
curved-crystal monochromator.
The total exposure time was 7.00 hours. The frames were integrated with the Bruker SAINT software
package using a SAINT V8.38A (Bruker AXS, 2013) algorithm. The integration of the data using a monoclinic
unit cell yielded a total of 83773 reflections to a maximum θ angle of 24.71° (0.85 Å resolution), of which
8811 were independent (average redundancy 9.508, completeness = 100.0%, R
int
= 17.78%, R
sig
= 10.22%)
and 5674 (64.40%) were greater than 2σ(F
2
). The final cell constants of a = 13.400(5) Å, b = 20.266(8) Å, c
= 19.218(8) Å, β = 97.812(6)°, volume = 5170.(4) Å
3
, are based upon the refinement of the XYZ-centroids
of 36 reflections above 20 σ(I) with 2.954° < 2θ < 32.19°. Data were corrected for absorption effects using
236
the multi-scan method (SADABS). The calculated minimum and maximum transmission coefficients (based
on crystal size) are 0.5670 and 0.9130.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/c 1, with Z = 4 for the formula unit, C
44
H
71
Cl
2
F
3
N
3
O
4
P
3
Ru
3
S. The final anisotropic full-matrix
least-squares refinement on F
2
with 613 variables converged at R1 = 4.09%, for the observed data and
wR2 = 7.71% for all data. The goodness-of-fit was 1.002. The largest peak in the final difference electron
density synthesis was 0.813 e
-
/Å
3
and the largest hole was -0.896 e
-
/Å
3
with an RMS deviation of 0.119 e
-
/Å
3
. On the basis of the final model, the calculated density was 1.621 g/cm
3
and F(000), 2568 e
-
.
Table A.27. Sample and crystal data for 4.4.
Chemical formula C
44
H
71
Cl
2
F
3
N
3
O
4
P
3
Ru
3
S
Formula weight 1262.11 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.080 x 0.090 x 0.554 mm
Crystal habit green needle
Crystal system monoclinic
Space group P 1 21/c 1
Unit cell dimensions a = 13.400(5) Å α = 90°
b = 20.266(8) Å β = 97.812(6)°
c = 19.218(8) Å γ = 90°
Volume 5170.(4) Å
3
Z 4
Density (calculated) 1.621 g/cm
3
Absorption coefficient 1.155 mm
-1
F(000) 2568
Table A.28. Data collection and structure refinement for 4.4.
Diffractometer Bruker APEX DUO
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.47 to 24.71°
Index ranges -15<=h<=15, -23<=k<=23, -22<=l<=22
Reflections collected 83773
Independent reflections 8811 [R(int) = 0.1778]
237
Coverage of independent reflections 100.0%
Absorption correction multi-scan
Max. and min. transmission 0.9130 and 0.5670
Structure solution technique direct methods
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXTL XL 2017/1 (Bruker AXS, 2017)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 8811 / 71 / 613
Goodness-of-fit on F
2
1.002
Δ/σ
max
0.015
Final R indices 5674 data; I>2σ(I) R1 = 0.0409, wR2 = 0.0700
all data R1 = 0.0835, wR2 = 0.0771
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0115P)
2
]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 0.813 and -0.896 eÅ
-3
R.M.S. deviation from mean 0.119 eÅ
-3
Table A.29. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 4.4.
x/a y/b z/c U(eq)
C1 0.3878(4) 0.3492(3) 0.3399(3) 0.0158(13)
C2 0.3734(4) 0.4114(3) 0.3681(3) 0.0198(14)
C3 0.4522(4) 0.4477(3) 0.4018(3) 0.0188(14)
C4 0.5492(4) 0.4221(3) 0.4106(3) 0.0210(14)
C5 0.5624(4) 0.3603(3) 0.3846(3) 0.0154(13)
C6 0.6640(3) 0.3263(3) 0.3918(3) 0.0191(14)
C7 0.6348(4) 0.2123(3) 0.4836(3) 0.0261(15)
C8 0.5623(4) 0.2598(3) 0.5112(3) 0.0291(15)
C9 0.7331(4) 0.2137(3) 0.5336(3) 0.0372(17)
C10 0.5911(4) 0.1422(3) 0.4840(3) 0.0323(16)
C11 0.7688(4) 0.2046(3) 0.3643(4) 0.0292(16)
C12 0.8611(4) 0.2411(3) 0.4030(4) 0.0341(17)
C13 0.7766(4) 0.1295(3) 0.3782(4) 0.048(2)
C14 0.7679(4) 0.2155(3) 0.2864(3) 0.0394(18)
C15 0.3635(4) 0.1394(3) 0.1273(3) 0.0247(15)
C16 0.3542(4) 0.1208(3) 0.0590(3) 0.0262(15)
C17 0.2760(4) 0.0794(3) 0.0331(3) 0.0274(15)
C18 0.2113(4) 0.0580(3) 0.0784(3) 0.0230(14)
C19 0.2251(4) 0.0781(2) 0.1472(3) 0.0165(13)
C20 0.1570(4) 0.0560(3) 0.1983(3) 0.0216(14)
C21 0.2899(4) 0.9804(3) 0.3036(3) 0.0218(14)
C22 0.3476(4) 0.9682(3) 0.2407(3) 0.0216(14)
238
x/a y/b z/c U(eq)
C23 0.3665(4) 0.9848(3) 0.3691(3) 0.0297(16)
C24 0.2214(4) 0.9206(3) 0.3089(3) 0.0294(16)
C25 0.1205(4) 0.0694(3) 0.3444(3) 0.0212(14)
C26 0.0309(4) 0.0231(3) 0.3195(3) 0.0247(15)
C27 0.1609(4) 0.0561(3) 0.4201(3) 0.0304(16)
C28 0.0787(4) 0.1393(3) 0.3385(3) 0.0294(16)
C29 0.1536(4) 0.3032(3) 0.4053(3) 0.0180(13)
C30 0.0822(4) 0.3325(3) 0.4388(3) 0.0217(14)
C31 0.0360(4) 0.3894(3) 0.4125(3) 0.0240(15)
C32 0.0628(4) 0.4140(3) 0.3510(3) 0.0240(14)
C33 0.1337(4) 0.3812(3) 0.3174(3) 0.0196(14)
C34 0.1638(4) 0.4073(3) 0.2499(3) 0.0194(13)
C35 0.1083(4) 0.3016(3) 0.1505(3) 0.0216(14)
C36 0.1363(4) 0.2364(3) 0.1192(3) 0.0267(15)
C37 0.0287(4) 0.2873(3) 0.1995(3) 0.0261(15)
C38 0.0553(4) 0.3453(3) 0.0907(3) 0.0273(15)
C39 0.2993(4) 0.3865(3) 0.1458(3) 0.0231(14)
C40 0.2467(4) 0.4482(3) 0.1118(3) 0.0287(15)
C41 0.3951(4) 0.4105(3) 0.1901(3) 0.0267(15)
C42 0.3277(4) 0.3397(3) 0.0895(3) 0.0297(16)
C43 0.5554(4) 0.2603(3) 0.2403(3) 0.0242(15)
Cl1 0.50124(9) 0.11443(7) 0.28800(8) 0.0236(4)
Cl2 0.36379(9) 0.19998(6) 0.39087(7) 0.0191(3)
N1 0.4837(3) 0.3261(2) 0.3498(2) 0.0143(11)
N2 0.3006(3) 0.1204(2) 0.1728(2) 0.0173(11)
N3 0.1803(3) 0.3263(2) 0.3447(2) 0.0166(11)
O1 0.5832(3) 0.2821(2) 0.1918(2) 0.0339(11)
P1 0.64778(10) 0.23672(7) 0.39108(8) 0.0206(4)
P2 0.22462(10) 0.06257(7) 0.28708(8) 0.0165(3)
P3 0.22144(10) 0.34061(7) 0.20477(8) 0.0177(3)
Ru1 0.49760(3) 0.23139(2) 0.31462(2) 0.01709(12)
Ru2 0.32218(3) 0.14940(2) 0.27441(2) 0.01606(12)
Ru3 0.29150(3) 0.27986(2) 0.29629(2) 0.01561(12)
C44 0.2287(10) 0.5909(7) 0.3949(8) 0.039(3)
F1 0.2916(8) 0.5739(6) 0.4532(6) 0.0514(13)
F2 0.2284(16) 0.5398(8) 0.3520(9) 0.0514(13)
F3 0.270(2) 0.6429(10) 0.3684(13) 0.0514(13)
S1 0.1014(8) 0.6102(6) 0.4062(5) 0.0330(14)
O2 0.0705(9) 0.6389(7) 0.3340(6) 0.0389(13)
O3 0.1113(14) 0.6587(8) 0.4614(7) 0.0389(13)
O4 0.050(2) 0.5508(11) 0.4190(12) 0.0389(13)
239
x/a y/b z/c U(eq)
C44A 0.2211(12) 0.5857(9) 0.3821(9) 0.039(3)
F1A 0.2699(10) 0.5456(7) 0.4349(7) 0.0514(13)
F2A 0.1993(12) 0.5550(8) 0.3206(8) 0.0514(13)
F3A 0.2781(18) 0.6383(10) 0.3784(14) 0.0514(13)
S1A 0.1068(8) 0.6033(5) 0.4196(5) 0.0330(14)
O2A 0.0488(10) 0.6245(8) 0.3499(7) 0.0389(13)
O3A 0.1350(13) 0.6428(8) 0.4782(8) 0.0389(13)
O4A 0.0809(12) 0.5382(7) 0.4377(11) 0.0389(13)
C44B 0.1855(12) 0.6036(8) 0.3614(7) 0.039(3)
F1B 0.2357(13) 0.5482(8) 0.3418(9) 0.0514(13)
F2B 0.1190(7) 0.6160(5) 0.3076(5) 0.0514(13)
F3B 0.2621(15) 0.6475(9) 0.3690(13) 0.0514(13)
S1B 0.1276(6) 0.5937(5) 0.4398(4) 0.0330(14)
O2B 0.0922(11) 0.6670(6) 0.4437(8) 0.0389(13)
O3B 0.2027(7) 0.5765(5) 0.4926(5) 0.0389(13)
O4B 0.0447(17) 0.5502(11) 0.4239(12) 0.0389(13)
Table A.30. Bond lengths (Å) for 4.4.
C1-N1 1.356(6) C1-C2 1.396(7)
C1-Ru3 2.012(5) C2-C3 1.376(7)
C2-H2 0.95 C3-C4 1.387(7)
C3-H3 0.95 C4-C5 1.369(7)
C4-H4 0.95 C5-N1 1.360(6)
C5-C6 1.515(6) C6-P1 1.829(5)
C6-H6A 0.99 C6-H6AB 0.99
C7-C8 1.514(7) C7-C9 1.521(7)
C7-C10 1.538(7) C7-P1 1.877(6)
C8-H8A 0.98 C8-H8B 0.98
C8-H8C 0.98 C9-H9A 0.98
C9-H9B 0.98 C9-H9C 0.98
C10-H10A 0.98 C10-H10B 0.98
C10-H10C 0.98 C11-C14 1.512(8)
C11-C12 1.543(7) C11-C13 1.546(8)
C11-P1 1.883(5) C12-H12A 0.98
C12-H12B 0.98 C12-H12C 0.98
C13-H13A 0.98 C13-H13B 0.98
C13-H13C 0.98 C14-H14A 0.98
C14-H14B 0.98 C14-H14C 0.98
C15-N2 1.350(6) C15-C16 1.355(8)
C15-H15 0.95 C16-C17 1.381(7)
C16-H16 0.95 C17-C18 1.380(7)
240
C17-H17 0.95 C18-C19 1.372(7)
C18-H18 0.95 C19-N2 1.367(6)
C19-C20 1.497(7) C20-P2 1.825(6)
C20-H20A 0.99 C20-H20B 0.99
C21-C23 1.515(8) C21-C24 1.532(7)
C21-C22 1.540(7) C21-P2 1.888(6)
C22-H22A 0.98 C22-H22B 0.98
C22-H22C 0.98 C23-H23A 0.98
C23-H23B 0.98 C23-H23C 0.98
C24-H24A 0.98 C24-H24B 0.98
C24-H24C 0.98 C25-C27 1.506(8)
C25-C28 1.522(7) C25-C26 1.547(7)
C25-P2 1.896(5) C26-H26A 0.98
C26-H26B 0.98 C26-H26C 0.98
C27-H27A 0.98 C27-H27B 0.98
C27-H27C 0.98 C28-H28A 0.98
C28-H28B 0.98 C28-H28C 0.98
C29-N3 1.347(6) C29-C30 1.362(7)
C29-H29 0.95 C30-C31 1.372(7)
C30-H30 0.95 C31-C32 1.376(7)
C31-H31 0.95 C32-C33 1.388(7)
C32-H32 0.95 C33-N3 1.349(6)
C33-C34 1.506(7) C34-P3 1.832(5)
C34-H34A 0.99 C34-H34B 0.99
C35-C36 1.520(7) C35-C37 1.544(7)
C35-C38 1.545(7) C35-P3 1.893(6)
C36-H36A 0.98 C36-H36B 0.98
C36-H36C 0.98 C37-H37A 0.98
C37-H37B 0.98 C37-H37C 0.98
C38-H38A 0.98 C38-H38B 0.98
C38-H38C 0.98 C39-C41 1.521(7)
C39-C42 1.526(7) C39-C40 1.537(7)
C39-P3 1.886(5) C40-H40A 0.98
C40-H40B 0.98 C40-H40C 0.98
C41-H41A 0.98 C41-H41B 0.98
C41-H41C 0.98 C42-H42A 0.98
C42-H42B 0.98 C42-H42C 0.98
C43-O1 1.140(6) C43-Ru1 1.812(6)
Cl1-Ru1 2.4268(17) Cl1-Ru2 2.4814(16)
Cl2-Ru2 2.4559(17) Cl2-Ru3 2.5267(16)
Cl2-Ru1 2.5459(14) N1-Ru1 2.051(4)
N2-Ru2 2.022(5) N3-Ru3 2.085(4)
241
P1-Ru1 2.3274(16) P2-Ru2 2.2252(16)
P3-Ru3 2.2454(17) Ru1-Ru2 2.8964(10)
Ru1-Ru3 2.9071(12) Ru2-Ru3 2.7171(12)
C44-F3 1.320(11) C44-F2 1.323(11)
C44-F1 1.353(11) C44-S1 1.792(10)
S1-O4 1.426(10) S1-O3 1.438(11)
S1-O2 1.510(10) C44A-F3A 1.318(15)
C44A-F2A 1.333(16) C44A-F1A 1.391(15)
C44A-S1A 1.813(14) S1A-O3A 1.391(13)
S1A-O4A 1.421(13) S1A-O2A 1.516(13)
C44B-F2B 1.295(14) C44B-F3B 1.352(14)
C44B-F1B 1.386(16) C44B-S1B 1.798(12)
S1B-O3B 1.373(10) S1B-O4B 1.418(12)
S1B-O2B 1.565(12)
Table A.31. Bond angles (°) for 4.4.
N1-C1-C2 115.9(5) N1-C1-Ru3 111.0(4)
C2-C1-Ru3 132.6(4) C3-C2-C1 121.9(5)
C3-C2-H2 119.1 C1-C2-H2 119.1
C2-C3-C4 120.3(5) C2-C3-H3 119.9
C4-C3-H3 119.9 C5-C4-C3 117.6(5)
C5-C4-H4 121.2 C3-C4-H4 121.2
N1-C5-C4 121.1(5) N1-C5-C6 116.1(5)
C4-C5-C6 122.8(5) C5-C6-P1 110.3(3)
C5-C6-H6A 109.6 P1-C6-H6A 109.6
C5-C6-H6AB 109.6 P1-C6-H6AB 109.6
H6A-C6-H6AB 108.1 C8-C7-C9 108.0(5)
C8-C7-C10 108.8(4) C9-C7-C10 108.2(5)
C8-C7-P1 108.1(4) C9-C7-P1 114.2(4)
C10-C7-P1 109.4(4) C7-C8-H8A 109.5
C7-C8-H8B 109.5 H8A-C8-H8B 109.5
C7-C8-H8C 109.5 H8A-C8-H8C 109.5
H8B-C8-H8C 109.5 C7-C9-H9A 109.5
C7-C9-H9B 109.5 H9A-C9-H9B 109.5
C7-C9-H9C 109.5 H9A-C9-H9C 109.5
H9B-C9-H9C 109.5 C7-C10-H10A 109.5
C7-C10-H10B 109.5 H10A-C10-H10B 109.5
C7-C10-H10C 109.5 H10A-C10-H10C 109.5
H10B-C10-H10C 109.5 C14-C11-C12 107.8(5)
C14-C11-C13 107.8(5) C12-C11-C13 111.0(5)
C14-C11-P1 109.2(4) C12-C11-P1 111.5(4)
C13-C11-P1 109.5(4) C11-C12-H12A 109.5
242
C11-C12-H12B 109.5 H12A-C12-H12B 109.5
C11-C12-H12C 109.5 H12A-C12-H12C 109.5
H12B-C12-H12C 109.5 C11-C13-H13A 109.5
C11-C13-H13B 109.5 H13A-C13-H13B 109.5
C11-C13-H13C 109.5 H13A-C13-H13C 109.5
H13B-C13-H13C 109.5 C11-C14-H14A 109.5
C11-C14-H14B 109.5 H14A-C14-H14B 109.5
C11-C14-H14C 109.5 H14A-C14-H14C 109.5
H14B-C14-H14C 109.5 N2-C15-C16 124.4(5)
N2-C15-H15 117.8 C16-C15-H15 117.8
C15-C16-C17 118.8(5) C15-C16-H16 120.6
C17-C16-H16 120.6 C18-C17-C16 118.4(6)
C18-C17-H17 120.8 C16-C17-H17 120.8
C19-C18-C17 120.1(5) C19-C18-H18 120.0
C17-C18-H18 120.0 N2-C19-C18 121.9(5)
N2-C19-C20 116.1(5) C18-C19-C20 122.0(5)
C19-C20-P2 108.8(4) C19-C20-H20A 109.9
P2-C20-H20A 109.9 C19-C20-H20B 109.9
P2-C20-H20B 109.9 H20A-C20-H20B 108.3
C23-C21-C24 109.6(5) C23-C21-C22 107.8(4)
C24-C21-C22 107.1(4) C23-C21-P2 109.4(4)
C24-C21-P2 116.1(4) C22-C21-P2 106.3(4)
C21-C22-H22A 109.5 C21-C22-H22B 109.5
H22A-C22-H22B 109.5 C21-C22-H22C 109.5
H22A-C22-H22C 109.5 H22B-C22-H22C 109.5
C21-C23-H23A 109.5 C21-C23-H23B 109.5
H23A-C23-H23B 109.5 C21-C23-H23C 109.5
H23A-C23-H23C 109.5 H23B-C23-H23C 109.5
C21-C24-H24A 109.5 C21-C24-H24B 109.5
H24A-C24-H24B 109.5 C21-C24-H24C 109.5
H24A-C24-H24C 109.5 H24B-C24-H24C 109.5
C27-C25-C28 108.6(5) C27-C25-C26 110.6(5)
C28-C25-C26 106.2(4) C27-C25-P2 110.6(4)
C28-C25-P2 108.5(4) C26-C25-P2 112.2(4)
C25-C26-H26A 109.5 C25-C26-H26B 109.5
H26A-C26-H26B 109.5 C25-C26-H26C 109.5
H26A-C26-H26C 109.5 H26B-C26-H26C 109.5
C25-C27-H27A 109.5 C25-C27-H27B 109.5
H27A-C27-H27B 109.5 C25-C27-H27C 109.5
H27A-C27-H27C 109.5 H27B-C27-H27C 109.5
C25-C28-H28A 109.5 C25-C28-H28B 109.5
H28A-C28-H28B 109.5 C25-C28-H28C 109.5
243
H28A-C28-H28C 109.5 H28B-C28-H28C 109.5
N3-C29-C30 123.0(5) N3-C29-H29 118.5
C30-C29-H29 118.5 C29-C30-C31 120.2(5)
C29-C30-H30 119.9 C31-C30-H30 119.9
C30-C31-C32 117.7(5) C30-C31-H31 121.2
C32-C31-H31 121.2 C31-C32-C33 120.1(5)
C31-C32-H32 120.0 C33-C32-H32 120.0
N3-C33-C32 121.6(5) N3-C33-C34 117.5(4)
C32-C33-C34 120.9(5) C33-C34-P3 109.1(4)
C33-C34-H34A 109.9 P3-C34-H34A 109.9
C33-C34-H34B 109.9 P3-C34-H34B 109.9
H34A-C34-H34B 108.3 C36-C35-C37 107.9(4)
C36-C35-C38 108.5(5) C37-C35-C38 106.0(4)
C36-C35-P3 111.0(3) C37-C35-P3 108.1(4)
C38-C35-P3 115.0(4) C35-C36-H36A 109.5
C35-C36-H36B 109.5 H36A-C36-H36B 109.5
C35-C36-H36C 109.5 H36A-C36-H36C 109.5
H36B-C36-H36C 109.5 C35-C37-H37A 109.5
C35-C37-H37B 109.5 H37A-C37-H37B 109.5
C35-C37-H37C 109.5 H37A-C37-H37C 109.5
H37B-C37-H37C 109.5 C35-C38-H38A 109.5
C35-C38-H38B 109.5 H38A-C38-H38B 109.5
C35-C38-H38C 109.5 H38A-C38-H38C 109.5
H38B-C38-H38C 109.5 C41-C39-C42 108.8(4)
C41-C39-C40 106.3(5) C42-C39-C40 110.3(5)
C41-C39-P3 108.4(4) C42-C39-P3 109.4(4)
C40-C39-P3 113.4(4) C39-C40-H40A 109.5
C39-C40-H40B 109.5 H40A-C40-H40B 109.5
C39-C40-H40C 109.5 H40A-C40-H40C 109.5
H40B-C40-H40C 109.5 C39-C41-H41A 109.5
C39-C41-H41B 109.5 H41A-C41-H41B 109.5
C39-C41-H41C 109.5 H41A-C41-H41C 109.5
H41B-C41-H41C 109.5 C39-C42-H42A 109.5
C39-C42-H42B 109.5 H42A-C42-H42B 109.5
C39-C42-H42C 109.5 H42A-C42-H42C 109.5
H42B-C42-H42C 109.5 O1-C43-Ru1 173.1(5)
Ru1-Cl1-Ru2 72.32(4) Ru2-Cl2-Ru3 66.07(5)
Ru2-Cl2-Ru1 70.74(4) Ru3-Cl2-Ru1 69.93(4)
C1-N1-C5 123.3(4) C1-N1-Ru1 113.8(3)
C5-N1-Ru1 122.7(3) C15-N2-C19 116.3(5)
C15-N2-Ru2 121.5(4) C19-N2-Ru2 122.1(3)
C29-N3-C33 117.4(4) C29-N3-Ru3 121.3(4)
244
C33-N3-Ru3 121.3(3) C6-P1-C7 106.3(3)
C6-P1-C11 103.9(2) C7-P1-C11 111.2(3)
C6-P1-Ru1 98.19(17) C7-P1-Ru1 113.75(17)
C11-P1-Ru1 121.0(2) C20-P2-C21 104.6(3)
C20-P2-C25 103.7(2) C21-P2-C25 109.1(2)
C20-P2-Ru2 100.38(18) C21-P2-Ru2 116.78(17)
C25-P2-Ru2 119.69(18) C34-P3-C39 102.9(2)
C34-P3-C35 102.2(2) C39-P3-C35 110.0(3)
C34-P3-Ru3 101.10(19) C39-P3-Ru3 122.30(18)
C35-P3-Ru3 114.88(18) C43-Ru1-N1 91.4(2)
C43-Ru1-P1 93.25(18) N1-Ru1-P1 81.84(12)
C43-Ru1-Cl1 97.28(18) N1-Ru1-Cl1 171.29(12)
P1-Ru1-Cl1 97.93(5) C43-Ru1-Cl2 160.83(17)
N1-Ru1-Cl2 86.66(11) P1-Ru1-Cl2 105.33(6)
Cl1-Ru1-Cl2 85.01(5) C43-Ru1-Ru2 113.19(18)
N1-Ru1-Ru2 121.18(11) P1-Ru1-Ru2 142.72(4)
Cl1-Ru1-Ru2 54.71(3) Cl2-Ru1-Ru2 53.18(4)
C43-Ru1-Ru3 107.24(17) N1-Ru1-Ru3 66.20(11)
P1-Ru1-Ru3 141.86(4) Cl1-Ru1-Ru3 110.52(3)
Cl2-Ru1-Ru3 54.72(4) Ru2-Ru1-Ru3 55.83(3)
N2-Ru2-P2 82.36(12) N2-Ru2-Cl2 170.50(12)
P2-Ru2-Cl2 107.12(5) N2-Ru2-Cl1 91.60(11)
P2-Ru2-Cl1 109.67(6) Cl2-Ru2-Cl1 85.80(5)
N2-Ru2-Ru3 115.29(12) P2-Ru2-Ru3 130.47(4)
Cl2-Ru2-Ru3 58.21(3) Cl1-Ru2-Ru3 115.22(4)
N2-Ru2-Ru1 115.37(11) P2-Ru2-Ru1 153.13(5)
Cl2-Ru2-Ru1 56.08(3) Cl1-Ru2-Ru1 52.97(4)
Ru3-Ru2-Ru1 62.28(3) C1-Ru3-N3 87.47(18)
C1-Ru3-P3 96.88(15) N3-Ru3-P3 81.63(13)
C1-Ru3-Cl2 89.20(15) N3-Ru3-Cl2 101.25(13)
P3-Ru3-Cl2 173.41(5) C1-Ru3-Ru2 129.93(15)
N3-Ru3-Ru2 129.81(12) P3-Ru3-Ru2 117.92(5)
Cl2-Ru3-Ru2 55.71(4) C1-Ru3-Ru1 68.92(14)
N3-Ru3-Ru1 145.38(12) P3-Ru3-Ru1 124.70(4)
Cl2-Ru3-Ru1 55.35(3) Ru2-Ru3-Ru1 61.886(16)
F3-C44-F2 110.6(12) F3-C44-F1 106.1(12)
F2-C44-F1 105.5(11) F3-C44-S1 108.9(14)
F2-C44-S1 108.9(12) F1-C44-S1 116.8(10)
O4-S1-O3 116.6(10) O4-S1-O2 113.8(9)
O3-S1-O2 113.7(8) O4-S1-C44 109.2(13)
O3-S1-C44 104.2(10) O2-S1-C44 96.8(8)
F3A-C44A-F2A 112.7(18) F3A-C44A-F1A 107.1(15)
245
F2A-C44A-F1A 113.4(15) F3A-C44A-S1A 113.0(16)
F2A-C44A-S1A 110.4(13) F1A-C44A-S1A 99.5(11)
O3A-S1A-O4A 112.6(11) O3A-S1A-O2A 127.0(11)
O4A-S1A-O2A 111.6(11) O3A-S1A-C44A 106.5(10)
O4A-S1A-C44A 99.4(10) O2A-S1A-C44A 93.7(9)
F2B-C44B-F3B 112.9(15) F2B-C44B-F1B 104.3(13)
F3B-C44B-F1B 99.9(14) F2B-C44B-S1B 111.3(11)
F3B-C44B-S1B 112.9(13) F1B-C44B-S1B 114.7(12)
O3B-S1B-O4B 118.5(12) O3B-S1B-O2B 113.7(8)
O4B-S1B-O2B 111.5(13) O3B-S1B-C44B 106.9(8)
O4B-S1B-C44B 107.6(10) O2B-S1B-C44B 95.9(8)
Table A.32. Torsion angles (°) for 4.4.
N1-C1-C2-C3 2.0(8) Ru3-C1-C2-C3 173.4(4)
C1-C2-C3-C4 -2.0(8) C2-C3-C4-C5 0.1(8)
C3-C4-C5-N1 1.7(8) C3-C4-C5-C6 -178.9(5)
N1-C5-C6-P1 -27.6(6) C4-C5-C6-P1 153.0(5)
N2-C15-C16-C17 -0.3(9) C15-C16-C17-C18 -0.9(8)
C16-C17-C18-C19 0.3(8) C17-C18-C19-N2 1.5(8)
C17-C18-C19-C20 -179.8(5) N2-C19-C20-P2 -24.6(6)
C18-C19-C20-P2 156.6(4) N3-C29-C30-C31 -2.2(8)
C29-C30-C31-C32 1.6(8) C30-C31-C32-C33 0.5(8)
C31-C32-C33-N3 -2.2(8) C31-C32-C33-C34 179.8(5)
N3-C33-C34-P3 21.6(6) C32-C33-C34-P3 -160.4(4)
C2-C1-N1-C5 -0.1(7) Ru3-C1-N1-C5 -173.4(4)
C2-C1-N1-Ru1 175.0(4) Ru3-C1-N1-Ru1 1.8(4)
C4-C5-N1-C1 -1.7(8) C6-C5-N1-C1 178.9(4)
C4-C5-N1-Ru1 -176.5(4) C6-C5-N1-Ru1 4.1(6)
C16-C15-N2-C19 2.0(8) C16-C15-N2-Ru2 178.8(4)
C18-C19-N2-C15 -2.5(7) C20-C19-N2-C15 178.7(4)
C18-C19-N2-Ru2 -179.3(4) C20-C19-N2-Ru2 1.9(6)
C30-C29-N3-C33 0.5(8) C30-C29-N3-Ru3 179.3(4)
C32-C33-N3-C29 1.7(8) C34-C33-N3-C29 179.7(4)
C32-C33-N3-Ru3 -177.1(4) C34-C33-N3-Ru3 0.9(6)
C5-C6-P1-C7 -84.4(4) C5-C6-P1-C11 158.2(4)
C5-C6-P1-Ru1 33.4(4) C8-C7-P1-C6 45.5(4)
C9-C7-P1-C6 -74.8(5) C10-C7-P1-C6 163.8(3)
C8-C7-P1-C11 157.9(4) C9-C7-P1-C11 37.6(5)
C10-C7-P1-C11 -83.7(4) C8-C7-P1-Ru1 -61.4(4)
C9-C7-P1-Ru1 178.3(4) C10-C7-P1-Ru1 56.9(4)
C14-C11-P1-C6 -75.4(4) C12-C11-P1-C6 43.6(5)
C13-C11-P1-C6 166.8(4) C14-C11-P1-C7 170.7(4)
246
C12-C11-P1-C7 -70.3(5) C13-C11-P1-C7 52.9(5)
C14-C11-P1-Ru1 33.2(5) C12-C11-P1-Ru1 152.2(4)
C13-C11-P1-Ru1 -84.6(5) C19-C20-P2-C21 -89.0(4)
C19-C20-P2-C25 156.7(4) C19-C20-P2-Ru2 32.4(4)
C23-C21-P2-C20 167.7(3) C24-C21-P2-C20 -67.5(5)
C22-C21-P2-C20 51.5(4) C23-C21-P2-C25 -81.8(4)
C24-C21-P2-C25 43.0(5) C22-C21-P2-C25 162.0(4)
C23-C21-P2-Ru2 57.9(4) C24-C21-P2-Ru2 -177.4(4)
C22-C21-P2-Ru2 -58.3(4) C27-C25-P2-C20 164.0(4)
C28-C25-P2-C20 -77.0(4) C26-C25-P2-C20 40.1(5)
C27-C25-P2-C21 53.0(5) C28-C25-P2-C21 172.0(4)
C26-C25-P2-C21 -71.0(5) C27-C25-P2-Ru2 -85.3(4)
C28-C25-P2-Ru2 33.7(5) C26-C25-P2-Ru2 150.7(3)
C33-C34-P3-C39 -157.7(4) C33-C34-P3-C35 88.2(4)
C33-C34-P3-Ru3 -30.6(4) C41-C39-P3-C34 78.0(4)
C42-C39-P3-C34 -163.5(4) C40-C39-P3-C34 -39.9(5)
C41-C39-P3-C35 -173.7(4) C42-C39-P3-C35 -55.2(4)
C40-C39-P3-C35 68.4(5) C41-C39-P3-Ru3 -34.3(5)
C42-C39-P3-Ru3 84.2(4) C40-C39-P3-Ru3 -152.1(4)
C36-C35-P3-C34 -169.0(4) C37-C35-P3-C34 -50.9(4)
C38-C35-P3-C34 67.4(4) C36-C35-P3-C39 82.2(4)
C37-C35-P3-C39 -159.7(4) C38-C35-P3-C39 -41.4(4)
C36-C35-P3-Ru3 -60.5(4) C37-C35-P3-Ru3 57.6(4)
C38-C35-P3-Ru3 175.8(3) F3-C44-S1-O4 166.7(14)
F2-C44-S1-O4 46.0(15) F1-C44-S1-O4 -73.2(14)
F3-C44-S1-O3 -68.1(14) F2-C44-S1-O3 171.2(12)
F1-C44-S1-O3 52.0(13) F3-C44-S1-O2 48.5(13)
F2-C44-S1-O2 -72.2(12) F1-C44-S1-O2 168.6(12)
F3A-C44A-S1A-O3A -44.9(19) F2A-C44A-S1A-O3A -172.1(15)
F1A-C44A-S1A-O3A 68.3(13) F3A-C44A-S1A-O4A -161.9(17)
F2A-C44A-S1A-O4A 70.8(17) F1A-C44A-S1A-O4A -48.7(14)
F3A-C44A-S1A-O2A 85.5(17) F2A-C44A-S1A-O2A -41.8(16)
F1A-C44A-S1A-O2A -161.3(12) F2B-C44B-S1B-O3B 176.2(12)
F3B-C44B-S1B-O3B -55.6(16) F1B-C44B-S1B-O3B 58.0(14)
F2B-C44B-S1B-O4B 47.9(17) F3B-C44B-S1B-O4B 176.1(18)
F1B-C44B-S1B-O4B -70.2(18) F2B-C44B-S1B-O2B -66.8(13)
F3B-C44B-S1B-O2B 61.3(15) F1B-C44B-S1B-O2B 175.0(13)
Table A.33. Anisotropic atomic displacement parameters (Å
2
) for 4.4.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.013(3) 0.022(3) 0.014(3) 0.006(3) 0.005(2) 0.000(2)
C2 0.013(3) 0.027(4) 0.021(4) 0.001(3) 0.006(3) -0.001(3)
247
U
11
U
22
U
33
U
23
U
13
U
12
C3 0.019(3) 0.018(3) 0.021(4) 0.001(3) 0.009(3) 0.003(3)
C4 0.016(3) 0.026(4) 0.021(4) 0.003(3) 0.001(3) -0.008(3)
C5 0.017(3) 0.018(3) 0.012(3) 0.005(3) 0.005(2) -0.004(2)
C6 0.007(3) 0.025(3) 0.025(4) 0.007(3) 0.001(3) -0.001(2)
C7 0.016(3) 0.033(4) 0.027(4) 0.007(3) -0.006(3) 0.000(3)
C8 0.025(3) 0.039(4) 0.023(4) 0.005(3) 0.002(3) -0.007(3)
C9 0.025(3) 0.044(4) 0.041(4) 0.012(4) -0.002(3) -0.005(3)
C10 0.018(3) 0.034(4) 0.044(4) 0.012(3) -0.001(3) -0.003(3)
C11 0.008(3) 0.026(4) 0.055(5) -0.005(3) 0.009(3) 0.003(2)
C12 0.010(3) 0.034(4) 0.059(5) -0.010(3) 0.005(3) -0.002(3)
C13 0.017(3) 0.036(4) 0.090(6) -0.016(4) 0.003(4) 0.004(3)
C14 0.014(3) 0.052(5) 0.055(5) -0.022(4) 0.016(3) 0.003(3)
C15 0.015(3) 0.020(4) 0.040(4) -0.002(3) 0.008(3) -0.004(3)
C16 0.019(3) 0.037(4) 0.025(4) 0.002(3) 0.014(3) 0.002(3)
C17 0.031(4) 0.031(4) 0.023(4) -0.002(3) 0.013(3) 0.007(3)
C18 0.021(3) 0.022(4) 0.027(4) -0.003(3) 0.006(3) 0.002(3)
C19 0.014(3) 0.011(3) 0.025(4) 0.002(3) 0.003(3) 0.005(2)
C20 0.019(3) 0.019(3) 0.029(4) -0.002(3) 0.014(3) -0.001(2)
C21 0.019(3) 0.024(3) 0.025(4) -0.002(3) 0.012(3) -0.003(3)
C22 0.020(3) 0.019(3) 0.028(4) -0.001(3) 0.014(3) 0.004(3)
C23 0.025(3) 0.035(4) 0.032(4) 0.016(3) 0.015(3) 0.006(3)
C24 0.027(3) 0.017(4) 0.047(5) 0.003(3) 0.015(3) 0.000(3)
C25 0.013(3) 0.027(4) 0.027(4) -0.002(3) 0.013(3) -0.001(3)
C26 0.013(3) 0.028(4) 0.035(4) -0.004(3) 0.015(3) -0.002(3)
C27 0.024(3) 0.043(4) 0.028(4) -0.004(3) 0.018(3) -0.002(3)
C28 0.021(3) 0.024(4) 0.048(5) -0.009(3) 0.019(3) -0.002(3)
C29 0.013(3) 0.022(3) 0.019(4) 0.000(3) 0.002(3) -0.003(2)
C30 0.015(3) 0.030(4) 0.022(4) 0.000(3) 0.007(3) -0.008(3)
C31 0.017(3) 0.034(4) 0.024(4) -0.006(3) 0.013(3) 0.004(3)
C32 0.018(3) 0.023(4) 0.031(4) -0.004(3) 0.004(3) 0.005(3)
C33 0.012(3) 0.027(4) 0.021(4) -0.002(3) 0.005(3) 0.000(3)
C34 0.015(3) 0.018(3) 0.024(4) 0.001(3) -0.001(3) 0.000(2)
C35 0.012(3) 0.032(4) 0.021(4) 0.003(3) 0.003(3) 0.000(3)
C36 0.025(3) 0.026(4) 0.029(4) -0.001(3) 0.002(3) 0.000(3)
C37 0.016(3) 0.026(4) 0.037(4) 0.005(3) 0.007(3) 0.004(3)
C38 0.024(3) 0.032(4) 0.026(4) -0.004(3) 0.001(3) -0.001(3)
C39 0.022(3) 0.030(4) 0.019(4) 0.007(3) 0.010(3) -0.001(3)
C40 0.029(3) 0.028(4) 0.030(4) 0.009(3) 0.007(3) 0.000(3)
C41 0.016(3) 0.038(4) 0.028(4) 0.007(3) 0.008(3) -0.007(3)
C42 0.028(3) 0.037(4) 0.027(4) 0.003(3) 0.013(3) 0.000(3)
C43 0.019(3) 0.035(4) 0.020(4) -0.006(3) 0.007(3) 0.001(3)
248
U
11
U
22
U
33
U
23
U
13
U
12
Cl1 0.0126(7) 0.0210(8) 0.0381(10) -0.0051(7) 0.0070(7) -0.0001(6)
Cl2 0.0122(7) 0.0218(8) 0.0240(9) 0.0033(6) 0.0050(6) -0.0009(6)
N1 0.011(2) 0.018(3) 0.016(3) -0.001(2) 0.005(2) -0.004(2)
N2 0.011(2) 0.020(3) 0.022(3) 0.003(2) 0.006(2) 0.004(2)
N3 0.009(2) 0.019(3) 0.022(3) 0.000(2) 0.004(2) 0.002(2)
O1 0.029(2) 0.046(3) 0.030(3) -0.001(2) 0.019(2) -0.007(2)
P1 0.0109(7) 0.0211(9) 0.0293(10) 0.0013(8) 0.0010(7) -0.0004(6)
P2 0.0116(7) 0.0188(9) 0.0202(9) 0.0000(7) 0.0064(7) 0.0004(6)
P3 0.0123(7) 0.0221(9) 0.0195(9) 0.0007(7) 0.0046(6) 0.0010(6)
Ru1 0.0098(2) 0.0192(3) 0.0235(3) -0.0005(2) 0.0063(2) -0.0013(2)
Ru2 0.0094(2) 0.0182(3) 0.0216(3) -0.0004(2) 0.00602(19) -0.0009(2)
Ru3 0.0098(2) 0.0188(3) 0.0191(3) 0.0003(2) 0.00507(19) -0.0002(2)
C44 0.074(9) 0.025(7) 0.012(8) -0.002(6) -0.019(7) 0.018(6)
F1 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F2 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F3 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
S1 0.025(3) 0.029(3) 0.046(5) 0.002(3) 0.009(3) -0.0055(19)
O2 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O3 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O4 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
C44A 0.074(9) 0.025(7) 0.012(8) -0.002(6) -0.019(7) 0.018(6)
F1A 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F2A 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F3A 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
S1A 0.025(3) 0.029(3) 0.046(5) 0.002(3) 0.009(3) -0.0055(19)
O2A 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O3A 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O4A 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
C44B 0.074(9) 0.025(7) 0.012(8) -0.002(6) -0.019(7) 0.018(6)
F1B 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F2B 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
F3B 0.055(3) 0.052(3) 0.050(3) -0.011(2) 0.019(2) -0.003(2)
S1B 0.025(3) 0.029(3) 0.046(5) 0.002(3) 0.009(3) -0.0055(19)
O2B 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O3B 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
O4B 0.033(3) 0.043(3) 0.041(4) 0.005(2) 0.009(2) -0.004(2)
Table A.34. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 4.4.
x/a y/b z/c U(eq)
H2 0.3072 0.4291 0.3638 0.024
H3 0.4403 0.4905 0.4190 0.023
249
x/a y/b z/c U(eq)
H4 0.6044 0.4466 0.4338 0.025
H6A 0.7047 0.3400 0.4364 0.023
H6AB 0.7004 0.3397 0.3526 0.023
H8A 0.5479 0.2448 0.5573 0.044
H8B 0.4994 0.2614 0.4786 0.044
H8C 0.5924 0.3039 0.5157 0.044
H9A 0.7644 0.2573 0.5320 0.056
H9B 0.7789 0.1800 0.5195 0.056
H9C 0.7195 0.2047 0.5815 0.056
H10A 0.5772 0.1313 0.5315 0.049
H10B 0.6398 0.1106 0.4696 0.049
H10C 0.5284 0.1399 0.4512 0.049
H12A 0.9227 0.2240 0.3873 0.051
H12B 0.8642 0.2342 0.4538 0.051
H12C 0.8551 0.2884 0.3927 0.051
H13A 0.7127 0.1084 0.3597 0.072
H13B 0.7910 0.1215 0.4289 0.072
H13C 0.8309 0.1110 0.3548 0.072
H14A 0.7574 0.2624 0.2756 0.059
H14B 0.7131 0.1898 0.2603 0.059
H14C 0.8324 0.2013 0.2727 0.059
H15 0.4178 0.1678 0.1443 0.03
H16 0.4007 0.1360 0.0294 0.031
H17 0.2670 0.0660 -0.0147 0.033
H18 0.1571 0.0294 0.0619 0.028
H20A 0.1359 0.0097 0.1884 0.026
H20B 0.0959 0.0839 0.1937 0.026
H22A 0.3877 -0.0722 0.2488 0.032
H22B 0.3922 0.0056 0.2355 0.032
H22C 0.2994 -0.0367 0.1978 0.032
H23A 0.3314 -0.0118 0.4105 0.045
H23B 0.4087 0.0239 0.3663 0.045
H23C 0.4089 -0.0548 0.3729 0.045
H24A 0.1710 -0.0816 0.2669 0.044
H24B 0.1873 -0.0750 0.3507 0.044
H24C 0.2620 -0.1198 0.3125 0.044
H26A -0.0206 0.0277 0.3509 0.037
H26B 0.0546 -0.0227 0.3205 0.037
H26C 0.0020 0.0348 0.2716 0.037
H27A 0.2210 0.0831 0.4337 0.046
H27B 0.1784 0.0093 0.4259 0.046
250
x/a y/b z/c U(eq)
H27C 0.1094 0.0673 0.4498 0.046
H28A 0.0249 0.1437 0.3680 0.044
H28B 0.0516 0.1485 0.2895 0.044
H28C 0.1326 0.1708 0.3542 0.044
H29 0.1861 0.2647 0.4255 0.022
H30 0.0642 0.3135 0.4806 0.026
H31 -0.0128 0.4110 0.4360 0.029
H32 0.0328 0.4535 0.3314 0.029
H34A 0.2123 0.4440 0.2600 0.023
H34B 0.1037 0.4244 0.2195 0.023
H36A 0.1716 0.2085 0.1564 0.04
H36B 0.1804 0.2447 0.0835 0.04
H36C 0.0751 0.2139 0.0977 0.04
H37A -0.0273 0.2625 0.1738 0.039
H37B 0.0035 0.3290 0.2161 0.039
H37C 0.0594 0.2612 0.2398 0.039
H38A 0.0986 0.3497 0.0538 0.041
H38B 0.0424 0.3890 0.1093 0.041
H38C -0.0087 0.3249 0.0711 0.041
H40A 0.2936 0.4726 0.0865 0.043
H40B 0.2250 0.4764 0.1484 0.043
H40C 0.1878 0.4349 0.0789 0.043
H41A 0.4354 0.4359 0.1605 0.04
H41B 0.4342 0.3725 0.2102 0.04
H41C 0.3776 0.4387 0.2281 0.04
H42A 0.2675 0.3290 0.0565 0.045
H42B 0.3562 0.2991 0.1116 0.045
H42C 0.3777 0.3610 0.0641 0.045
251
Crystal Structure of 4.6
A clear yellow prism-like specimen of C
36
H
58
Cl
3
F
3
N
2
O
7
P
2
Ru
2
S, approximate dimensions 0.050 mm x
0.200 mm x 0.200 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were
measured on a Bruker APEX II CCD Bruker APEX DUO system equipped with a fine-focus tube (MoKα , λ =
0.71073 Å) and a TRIUMPH curved-crystal monochromator.
The total exposure time was 3.50 hours. The frames were integrated with the Bruker SAINT software
package using a narrow-frame algorithm. The integration of the data using a monoclinic unit cell yielded
a total of 111769 reflections to a maximum θ angle of 30.55° (0.70 Å resolution), of which 13745 were
independent (average redundancy 8.132, completeness = 99.5%, R
int
= 3.85%, R
sig
= 2.07%) and 11955
(86.98%) were greater than 2σ(F
2
). The final cell constants of a = 17.416(4) Å, b = 15.909(4) Å, c = 17.479(4)
Å, β = 111.302(3)°, volume = 4512.1(18) Å
3
, are based upon the refinement of the XYZ-centroids of 9149
reflections above 20 σ(I) with 4.866° < 2θ < 60.98°. Data were corrected for absorption effects using the
252
Multi-Scan method (SADABS). The ratio of minimum to maximum apparent transmission was 0.897. The
calculated minimum and maximum transmission coefficients (based on crystal size) are 0.8220 and
0.9510.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/n 1, with Z = 4 for the formula unit, C
36
H
58
Cl
3
F
3
N
2
O
7
P
2
Ru
2
S. The final anisotropic full-matrix
least-squares refinement on F
2
with 561 variables converged at R1 = 2.65%, for the observed data and
wR2 = 6.72% for all data. The goodness-of-fit was 1.046. The largest peak in the final difference electron
density synthesis was 0.984 e
-
/Å
3
and the largest hole was -1.517 e
-
/Å
3
with an RMS deviation of 0.081 e
-
/Å
3
. On the basis of the final model, the calculated density was 1.605 g/cm
3
and F(000), 2224 e
-
.
Table A.35. Sample and crystal data for 4.6.
Chemical formula C
36
H
58
Cl
3
F
3
N
2
O
7
P
2
Ru
2
S
Formula weight 1090.33 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.050 x 0.200 x 0.200 mm
Crystal habit clear yellow prism
Crystal system monoclinic
Space group P 1 21/n 1
Unit cell dimensions a = 17.416(4) Å α = 90°
b = 15.909(4) Å β = 111.302(3)°
c = 17.479(4) Å γ = 90°
Volume 4512.1(18) Å
3
Z 4
Density (calculated) 1.605 g/cm
3
Absorption coefficient 1.023 mm
-1
F(000) 2224
Table A.36. Data collection and structure refinement for 4.6.
Diffractometer Bruker APEX II CCD Bruker APEX DUO
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.41 to 30.55°
Index ranges -24<=h<=24, -22<=k<=22, -24<=l<=24
Reflections collected 111769
Independent reflections 13745 [R(int) = 0.0385]
253
Coverage of independent reflections 99.5%
Absorption correction Multi-Scan
Max. and min. transmission 0.9510 and 0.8220
Structure solution technique direct methods
Structure solution program SHELXT 2014/5 (Sheldrick, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXL-2018/3 (Sheldrick, 2018)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 13745 / 6 / 561
Goodness-of-fit on F
2
1.046
Δ/σ
max
0.002
Final R indices 11955 data; I>2σ(I) R1 = 0.0265, wR2 = 0.0633
all data R1 = 0.0335, wR2 = 0.0672
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0259P)
2
+5.6689P]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 0.984 and -1.517 eÅ
-3
R.M.S. deviation from mean 0.081 eÅ
-3
Table A.37. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 4.6.
x/a y/b z/c U(eq)
C1 0.15270(10) 0.87951(11) 0.37614(10) 0.0150(3)
C2 0.15053(10) 0.67500(11) 0.36458(10) 0.0146(3)
C3 0.42489(10) 0.77227(11) 0.49365(10) 0.0141(3)
C4 0.5152(5) 0.7667(5) 0.5055(3) 0.0163(11)
C5 0.5285(3) 0.7324(3) 0.4300(3) 0.0236(9)
C6 0.6190(2) 0.7270(2) 0.4406(2) 0.0222(8)
C4' 0.5188(6) 0.7732(6) 0.5315(5) 0.0198(15)
C5' 0.5568(3) 0.7083(3) 0.4927(3) 0.0271(12)
C6' 0.5390(5) 0.7277(4) 0.4029(4) 0.0337(14)
C7 0.33786(10) 0.97542(11) 0.34139(10) 0.0144(3)
C8 0.35713(10) 0.04809(11) 0.30853(10) 0.0165(3)
C9 0.32861(11) 0.12478(11) 0.32551(10) 0.0179(3)
C10 0.28382(11) 0.12681(11) 0.37704(10) 0.0163(3)
C11 0.26850(10) 0.05217(10) 0.41056(10) 0.0133(3)
C12 0.22588(10) 0.05067(10) 0.47156(10) 0.0150(3)
C13 0.35928(11) 0.98258(11) 0.61907(10) 0.0169(3)
C14 0.41625(11) 0.01903(11) 0.57733(11) 0.0190(3)
C15 0.35252(13) 0.04940(12) 0.67985(11) 0.0236(4)
C16 0.39985(12) 0.90290(12) 0.66693(11) 0.0226(4)
C17 0.17473(12) 0.94504(11) 0.58271(11) 0.0190(3)
C18 0.14685(12) 0.03113(12) 0.60359(12) 0.0234(4)
C19 0.20576(14) 0.88934(13) 0.65973(12) 0.0255(4)
254
x/a y/b z/c U(eq)
C20 0.09836(12) 0.90268(14) 0.52023(13) 0.0260(4)
C21 0.33978(10) 0.58105(11) 0.33390(10) 0.0145(3)
C22 0.36550(10) 0.51099(11) 0.30274(10) 0.0158(3)
C23 0.34103(11) 0.43198(11) 0.31868(10) 0.0170(3)
C24 0.29246(11) 0.42547(11) 0.36631(10) 0.0165(3)
C25 0.27046(10) 0.49810(10) 0.39804(10) 0.0141(3)
C26 0.22331(11) 0.49460(10) 0.45501(10) 0.0151(3)
C27 0.34777(11) 0.56224(12) 0.60865(10) 0.0190(3)
C28 0.38403(13) 0.64280(13) 0.65756(12) 0.0258(4)
C29 0.33908(13) 0.49470(14) 0.66776(12) 0.0278(4)
C30 0.40865(11) 0.52757(12) 0.57078(11) 0.0213(4)
C31 0.16002(12) 0.59215(11) 0.56182(11) 0.0185(3)
C32 0.08415(12) 0.63049(14) 0.49513(13) 0.0264(4)
C33 0.18270(15) 0.64886(13) 0.63774(13) 0.0277(4)
C34 0.13465(13) 0.50408(12) 0.58118(12) 0.0225(4)
C35 0.03052(15) 0.22392(15) 0.32114(16) 0.0353(5)
Cl1 0.27265(2) 0.77866(2) 0.32116(2) 0.01343(7)
F1 0.02964(12) 0.17925(11) 0.38606(12) 0.0576(5)
F2 0.06336(11) 0.17317(10) 0.27987(11) 0.0529(4)
F3 0.95226(10) 0.23806(11) 0.27321(11) 0.0513(4)
N1 0.29355(8) 0.97686(9) 0.39084(8) 0.0126(2)
N2 0.29284(8) 0.57514(9) 0.38063(8) 0.0120(2)
O1 0.39098(7) 0.84356(7) 0.48628(7) 0.0144(2)
O2 0.38832(7) 0.70214(7) 0.48324(7) 0.0141(2)
O3 0.08509(8) 0.88783(9) 0.33261(8) 0.0223(3)
O4 0.08414(8) 0.67296(9) 0.31697(8) 0.0223(3)
O5 0.04493(10) 0.36495(11) 0.39656(11) 0.0367(4)
O6 0.08572(12) 0.35884(11) 0.27787(12) 0.0413(4)
O7 0.16937(10) 0.28891(11) 0.40636(12) 0.0373(4)
P1 0.25680(3) 0.95496(3) 0.53626(3) 0.01270(8)
P2 0.24768(3) 0.58837(3) 0.52238(2) 0.01275(8)
Ru1 0.26251(2) 0.86416(2) 0.43506(2) 0.01033(3)
Ru2 0.25973(2) 0.68479(2) 0.42857(2) 0.01008(3)
S1 0.08937(3) 0.32073(3) 0.35361(4) 0.02714(10)
C36 0.8721(3) 0.7363(4) 0.4161(3) 0.0405(11)
Cl2 0.93890(6) 0.77420(7) 0.36820(6) 0.0428(2)
Cl3 0.77075(6) 0.73031(6) 0.34503(8) 0.0515(3)
C36' 0.8550(7) 0.7292(10) 0.4315(8) 0.0405(11)
Cl2' 0.90039(14) 0.74119(16) 0.35661(13) 0.0428(2)
Cl3' 0.74770(14) 0.73054(14) 0.38755(18) 0.0515(3)
255
Table A.38. Bond lengths (Å) for 4.6.
C1-O3 1.154(2) C1-Ru1 1.8293(18)
C2-O4 1.154(2) C2-Ru2 1.8293(17)
C3-O1 1.263(2) C3-O2 1.265(2)
C3-C4 1.513(8) C3-C4' 1.525(9)
C4-C5 1.520(7) C4-H4A 0.99
C4-H4AB 0.99 C5-C6 1.523(5)
C5-H5A 0.99 C5-H5AB 0.99
C6-H6A 0.98 C6-H6B 0.98
C6-H6C 0.98 C4'-C5' 1.514(9)
C4'-H4'A 0.99 C4'-H4'B 0.99
C5'-C6' 1.516(8) C5'-H5'A 0.99
C5'-H5'B 0.99 C6'-H6'A 0.98
C6'-H6'B 0.98 C6'-H6'C 0.98
C7-N1 1.352(2) C7-C8 1.385(2)
C7-H7 0.95 C8-C9 1.389(3)
C8-H8 0.95 C9-C10 1.390(3)
C9-H9 0.95 C10-C11 1.392(2)
C10-H10 0.95 C11-N1 1.361(2)
C11-C12 1.504(2) C12-P1 1.8560(17)
C12-H12A 0.99 C12-H12B 0.99
C13-C15 1.537(2) C13-C16 1.542(3)
C13-C14 1.542(3) C13-P1 1.8965(18)
C14-H14A 0.98 C14-H14B 0.98
C14-H14C 0.98 C15-H15A 0.98
C15-H15B 0.98 C15-H15C 0.98
C16-H16A 0.98 C16-H16B 0.98
C16-H16C 0.98 C17-C20 1.536(3)
C17-C19 1.536(3) C17-C18 1.541(3)
C17-P1 1.8895(18) C18-H18A 0.98
C18-H18B 0.98 C18-H18C 0.98
C19-H19A 0.98 C19-H19B 0.98
C19-H19C 0.98 C20-H20A 0.98
C20-H20B 0.98 C20-H20C 0.98
C21-N2 1.352(2) C21-C22 1.384(2)
C21-H21 0.95 C22-C23 1.388(2)
C22-H22 0.95 C23-C24 1.390(2)
C23-H23 0.95 C24-C25 1.394(2)
C24-H24 0.95 C25-N2 1.354(2)
C25-C26 1.504(2) C26-P2 1.8518(17)
C26-H26A 0.99 C26-H26B 0.99
C27-C29 1.536(3) C27-C30 1.542(3)
256
C27-C28 1.543(3) C27-P2 1.8909(18)
C28-H28A 0.98 C28-H28B 0.98
C28-H28C 0.98 C29-H29A 0.98
C29-H29B 0.98 C29-H29C 0.98
C30-H30A 0.98 C30-H30B 0.98
C30-H30C 0.98 C31-C33 1.533(3)
C31-C32 1.535(3) C31-C34 1.543(2)
C31-P2 1.8906(18) C32-H32A 0.98
C32-H32B 0.98 C32-H32C 0.98
C33-H33A 0.98 C33-H33B 0.98
C33-H33C 0.98 C34-H34A 0.98
C34-H34B 0.98 C34-H34C 0.98
C35-F3 1.334(3) C35-F2 1.341(3)
C35-F1 1.344(3) C35-S1 1.823(2)
Cl1-Ru1 2.4700(6) Cl1-Ru2 2.4722(6)
N1-Ru1 2.0996(14) N2-Ru2 2.1045(14)
O1-Ru1 2.1119(13) O2-Ru2 2.1097(13)
O5-S1 1.4421(16) O6-S1 1.4364(19)
O7-S1 1.4541(19) P1-Ru1 2.3136(6)
P2-Ru2 2.3098(5) Ru1-Ru2 2.8556(7)
Ru1-H1 1.73(2) Ru2-H1 1.77(2)
C36-Cl3 1.753(5) C36-Cl2 1.767(4)
C36-H36A 0.99 C36-H36B 0.99
C36'-Cl3' 1.744(11) C36'-Cl2' 1.768(11)
C36'-H36C 0.99 C36'-H36D 0.99
Table A.39. Bond angles (°) for 4.6.
O3-C1-Ru1 173.73(15) O4-C2-Ru2 171.94(15)
O1-C3-O2 125.81(15) O1-C3-C4 119.4(3)
O2-C3-C4 114.3(3) O1-C3-C4' 115.1(4)
O2-C3-C4' 118.4(4) C3-C4-C5 112.3(4)
C3-C4-H4A 109.1 C5-C4-H4A 109.1
C3-C4-H4AB 109.1 C5-C4-H4AB 109.1
H4A-C4-H4AB 107.9 C4-C5-C6 113.1(4)
C4-C5-H5A 109.0 C6-C5-H5A 109.0
C4-C5-H5AB 109.0 C6-C5-H5AB 109.0
H5A-C5-H5AB 107.8 C5-C6-H6A 109.5
C5-C6-H6B 109.5 H6A-C6-H6B 109.5
C5-C6-H6C 109.5 H6A-C6-H6C 109.5
H6B-C6-H6C 109.5 C5'-C4'-C3 111.9(6)
C5'-C4'-H4'A 109.2 C3-C4'-H4'A 109.2
C5'-C4'-H4'B 109.2 C3-C4'-H4'B 109.2
257
H4'A-C4'-H4'B 107.9 C4'-C5'-C6' 111.6(5)
C4'-C5'-H5'A 109.3 C6'-C5'-H5'A 109.3
C4'-C5'-H5'B 109.3 C6'-C5'-H5'B 109.3
H5'A-C5'-H5'B 108.0 C5'-C6'-H6'A 109.5
C5'-C6'-H6'B 109.5 H6'A-C6'-H6'B 109.5
C5'-C6'-H6'C 109.5 H6'A-C6'-H6'C 109.5
H6'B-C6'-H6'C 109.5 N1-C7-C8 122.11(16)
N1-C7-H7 118.9 C8-C7-H7 118.9
C7-C8-C9 119.01(16) C7-C8-H8 120.5
C9-C8-H8 120.5 C8-C9-C10 119.16(16)
C8-C9-H9 120.4 C10-C9-H9 120.4
C9-C10-C11 119.43(16) C9-C10-H10 120.3
C11-C10-H10 120.3 N1-C11-C10 121.07(15)
N1-C11-C12 116.84(14) C10-C11-C12 122.07(15)
C11-C12-P1 109.64(11) C11-C12-H12A 109.7
P1-C12-H12A 109.7 C11-C12-H12B 109.7
P1-C12-H12B 109.7 H12A-C12-H12B 108.2
C15-C13-C16 109.19(15) C15-C13-C14 106.91(15)
C16-C13-C14 108.60(15) C15-C13-P1 113.61(13)
C16-C13-P1 110.02(12) C14-C13-P1 108.35(11)
C13-C14-H14A 109.5 C13-C14-H14B 109.5
H14A-C14-H14B 109.5 C13-C14-H14C 109.5
H14A-C14-H14C 109.5 H14B-C14-H14C 109.5
C13-C15-H15A 109.5 C13-C15-H15B 109.5
H15A-C15-H15B 109.5 C13-C15-H15C 109.5
H15A-C15-H15C 109.5 H15B-C15-H15C 109.5
C13-C16-H16A 109.5 C13-C16-H16B 109.5
H16A-C16-H16B 109.5 C13-C16-H16C 109.5
H16A-C16-H16C 109.5 H16B-C16-H16C 109.5
C20-C17-C19 107.94(16) C20-C17-C18 107.00(16)
C19-C17-C18 110.23(15) C20-C17-P1 109.02(12)
C19-C17-P1 110.15(13) C18-C17-P1 112.35(13)
C17-C18-H18A 109.5 C17-C18-H18B 109.5
H18A-C18-H18B 109.5 C17-C18-H18C 109.5
H18A-C18-H18C 109.5 H18B-C18-H18C 109.5
C17-C19-H19A 109.5 C17-C19-H19B 109.5
H19A-C19-H19B 109.5 C17-C19-H19C 109.5
H19A-C19-H19C 109.5 H19B-C19-H19C 109.5
C17-C20-H20A 109.5 C17-C20-H20B 109.5
H20A-C20-H20B 109.5 C17-C20-H20C 109.5
H20A-C20-H20C 109.5 H20B-C20-H20C 109.5
N2-C21-C22 122.31(16) N2-C21-H21 118.8
258
C22-C21-H21 118.8 C21-C22-C23 118.91(16)
C21-C22-H22 120.5 C23-C22-H22 120.5
C22-C23-C24 119.07(16) C22-C23-H23 120.5
C24-C23-H23 120.5 C23-C24-C25 119.45(16)
C23-C24-H24 120.3 C25-C24-H24 120.3
N2-C25-C24 121.17(15) N2-C25-C26 116.96(14)
C24-C25-C26 121.84(15) C25-C26-P2 109.69(11)
C25-C26-H26A 109.7 P2-C26-H26A 109.7
C25-C26-H26B 109.7 P2-C26-H26B 109.7
H26A-C26-H26B 108.2 C29-C27-C30 106.85(16)
C29-C27-C28 109.21(15) C30-C27-C28 109.16(16)
C29-C27-P2 113.75(13) C30-C27-P2 108.35(12)
C28-C27-P2 109.42(13) C27-C28-H28A 109.5
C27-C28-H28B 109.5 H28A-C28-H28B 109.5
C27-C28-H28C 109.5 H28A-C28-H28C 109.5
H28B-C28-H28C 109.5 C27-C29-H29A 109.5
C27-C29-H29B 109.5 H29A-C29-H29B 109.5
C27-C29-H29C 109.5 H29A-C29-H29C 109.5
H29B-C29-H29C 109.5 C27-C30-H30A 109.5
C27-C30-H30B 109.5 H30A-C30-H30B 109.5
C27-C30-H30C 109.5 H30A-C30-H30C 109.5
H30B-C30-H30C 109.5 C33-C31-C32 107.66(16)
C33-C31-C34 110.41(15) C32-C31-C34 106.93(16)
C33-C31-P2 110.25(13) C32-C31-P2 108.79(12)
C34-C31-P2 112.61(13) C31-C32-H32A 109.5
C31-C32-H32B 109.5 H32A-C32-H32B 109.5
C31-C32-H32C 109.5 H32A-C32-H32C 109.5
H32B-C32-H32C 109.5 C31-C33-H33A 109.5
C31-C33-H33B 109.5 H33A-C33-H33B 109.5
C31-C33-H33C 109.5 H33A-C33-H33C 109.5
H33B-C33-H33C 109.5 C31-C34-H34A 109.5
C31-C34-H34B 109.5 H34A-C34-H34B 109.5
C31-C34-H34C 109.5 H34A-C34-H34C 109.5
H34B-C34-H34C 109.5 F3-C35-F2 107.6(2)
F3-C35-F1 107.3(2) F2-C35-F1 105.9(2)
F3-C35-S1 112.56(18) F2-C35-S1 112.00(16)
F1-C35-S1 111.20(17) Ru1-Cl1-Ru2 70.59(2)
C7-N1-C11 119.12(14) C7-N1-Ru1 120.26(11)
C11-N1-Ru1 120.61(11) C21-N2-C25 119.03(14)
C21-N2-Ru2 119.74(11) C25-N2-Ru2 121.19(11)
C3-O1-Ru1 124.51(11) C3-O2-Ru2 125.23(11)
C12-P1-C17 103.48(8) C12-P1-C13 105.03(8)
259
C17-P1-C13 109.90(8) C12-P1-Ru1 97.46(6)
C17-P1-Ru1 121.71(6) C13-P1-Ru1 115.99(6)
C26-P2-C31 103.21(8) C26-P2-C27 105.18(8)
C31-P2-C27 110.42(8) C26-P2-Ru2 98.20(6)
C31-P2-Ru2 122.10(6) C27-P2-Ru2 114.64(6)
C1-Ru1-N1 92.01(6) C1-Ru1-O1 171.60(6)
N1-Ru1-O1 85.05(5) C1-Ru1-P1 91.18(5)
N1-Ru1-P1 80.60(4) O1-Ru1-P1 96.09(3)
C1-Ru1-Cl1 89.20(5) N1-Ru1-Cl1 94.02(4)
O1-Ru1-Cl1 83.17(3) P1-Ru1-Cl1 174.615(15)
C1-Ru1-Ru2 96.42(5) N1-Ru1-Ru2 147.31(4)
O1-Ru1-Ru2 82.06(3) P1-Ru1-Ru2 130.506(14)
Cl1-Ru1-Ru2 54.741(12) C1-Ru1-H1 90.0(8)
N1-Ru1-H1 175.7(8) O1-Ru1-H1 93.5(8)
P1-Ru1-H1 95.6(8) Cl1-Ru1-H1 89.8(8)
Ru2-Ru1-H1 35.9(8) C2-Ru2-N2 93.46(6)
C2-Ru2-O2 170.03(6) N2-Ru2-O2 83.65(5)
C2-Ru2-P2 92.01(5) N2-Ru2-P2 80.85(4)
O2-Ru2-P2 96.93(3) C2-Ru2-Cl1 87.05(5)
N2-Ru2-Cl1 94.85(4) O2-Ru2-Cl1 83.71(3)
P2-Ru2-Cl1 175.539(15) C2-Ru2-Ru1 96.21(5)
N2-Ru2-Ru1 147.25(4) O2-Ru2-Ru1 81.45(3)
P2-Ru2-Ru1 129.789(15) Cl1-Ru2-Ru1 54.667(14)
C2-Ru2-H1 91.4(8) N2-Ru2-H1 174.0(8)
O2-Ru2-H1 92.1(8) P2-Ru2-H1 95.6(8)
Cl1-Ru2-H1 88.8(8) Ru1-Ru2-H1 35.0(8)
O6-S1-O5 114.92(11) O6-S1-O7 116.28(11)
O5-S1-O7 114.31(11) O6-S1-C35 103.77(12)
O5-S1-C35 103.11(10) O7-S1-C35 101.79(11)
Cl3-C36-Cl2 110.5(3) Cl3-C36-H36A 109.6
Cl2-C36-H36A 109.6 Cl3-C36-H36B 109.6
Cl2-C36-H36B 109.6 H36A-C36-H36B 108.1
Cl3'-C36'-Cl2' 111.6(7) Cl3'-C36'-H36C 109.3
Cl2'-C36'-H36C 109.3 Cl3'-C36'-H36D 109.3
Cl2'-C36'-H36D 109.3 H36C-C36'-H36D 108.0
Table A.40. Anisotropic atomic displacement parameters (Å
2
) for 4.6.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.0179(7) 0.0142(7) 0.0148(7) 0.0001(6) 0.0084(6) -0.0014(6)
C2 0.0182(7) 0.0134(7) 0.0147(7) -0.0015(6) 0.0091(6) -0.0015(6)
C3 0.0130(7) 0.0156(7) 0.0131(7) 0.0003(6) 0.0042(6) -0.0016(6)
C4 0.0153(19) 0.0156(19) 0.018(3) -0.002(2) 0.006(2) -0.0017(14)
260
C5 0.0170(18) 0.033(2) 0.023(2) -0.0069(18) 0.0104(16) 0.0003(14)
C6 0.0180(15) 0.0238(17) 0.0286(17) -0.0032(13) 0.0129(13) 0.0009(12)
C4' 0.011(2) 0.018(3) 0.027(4) 0.000(3) 0.002(3) -0.0025(17)
C5' 0.017(2) 0.022(2) 0.043(3) 0.0033(19) 0.012(2) 0.0018(16)
C6' 0.035(3) 0.030(3) 0.044(4) -0.001(3) 0.024(3) -0.002(2)
C7 0.0133(7) 0.0158(7) 0.0135(7) 0.0007(6) 0.0043(6) -0.0004(6)
C8 0.0154(7) 0.0190(8) 0.0146(7) 0.0026(6) 0.0050(6) -0.0028(6)
C9 0.0206(8) 0.0160(8) 0.0144(7) 0.0038(6) 0.0033(6) -0.0036(6)
C10 0.0187(8) 0.0132(7) 0.0147(7) 0.0012(6) 0.0033(6) -0.0005(6)
C11 0.0122(7) 0.0124(7) 0.0131(7) 0.0002(5) 0.0020(6) -0.0005(5)
C12 0.0171(7) 0.0129(7) 0.0157(7) 0.0001(6) 0.0069(6) 0.0027(6)
C13 0.0197(8) 0.0156(8) 0.0128(7) -0.0024(6) 0.0030(6) 0.0000(6)
C14 0.0170(8) 0.0181(8) 0.0196(8) -0.0016(6) 0.0037(6) -0.0019(6)
C15 0.0286(9) 0.0213(9) 0.0187(8) -0.0067(7) 0.0061(7) -0.0006(7)
C16 0.0269(9) 0.0223(9) 0.0165(8) 0.0033(7) 0.0053(7) 0.0052(7)
C17 0.0250(9) 0.0182(8) 0.0193(8) -0.0023(6) 0.0144(7) -0.0013(7)
C18 0.0274(9) 0.0231(9) 0.0254(9) -0.0027(7) 0.0165(8) 0.0026(7)
C19 0.0391(11) 0.0214(9) 0.0235(9) 0.0009(7) 0.0205(8) -0.0014(8)
C20 0.0235(9) 0.0325(11) 0.0284(10) -0.0079(8) 0.0169(8) -0.0089(8)
C21 0.0143(7) 0.0165(7) 0.0125(7) 0.0004(6) 0.0046(6) -0.0002(6)
C22 0.0142(7) 0.0203(8) 0.0134(7) -0.0008(6) 0.0054(6) 0.0014(6)
C23 0.0175(7) 0.0173(8) 0.0155(7) -0.0038(6) 0.0052(6) 0.0025(6)
C24 0.0193(8) 0.0133(7) 0.0167(7) -0.0021(6) 0.0061(6) -0.0010(6)
C25 0.0148(7) 0.0143(7) 0.0118(7) -0.0004(5) 0.0032(6) -0.0012(6)
C26 0.0185(7) 0.0128(7) 0.0159(7) -0.0010(6) 0.0087(6) -0.0030(6)
C27 0.0216(8) 0.0195(8) 0.0130(7) 0.0040(6) 0.0029(6) -0.0021(7)
C28 0.0307(10) 0.0281(10) 0.0152(8) -0.0028(7) 0.0042(7) -0.0096(8)
C29 0.0316(10) 0.0295(10) 0.0200(9) 0.0111(8) 0.0066(8) -0.0004(8)
C30 0.0184(8) 0.0210(9) 0.0205(8) 0.0055(7) 0.0023(7) 0.0020(7)
C31 0.0249(8) 0.0163(8) 0.0204(8) 0.0007(6) 0.0156(7) -0.0017(6)
C32 0.0241(9) 0.0302(10) 0.0322(10) 0.0073(8) 0.0191(8) 0.0040(8)
C33 0.0450(12) 0.0210(9) 0.0279(10) -0.0052(7) 0.0261(9) -0.0045(8)
C34 0.0293(9) 0.0193(9) 0.0252(9) 0.0021(7) 0.0173(8) -0.0051(7)
C35 0.0358(12) 0.0348(12) 0.0436(13) -0.0103(10) 0.0245(11) -0.0105(10)
Cl1 0.01817(17) 0.01243(16) 0.01115(15) 0.00017(12) 0.00707(13) -0.00084(13)
F1 0.0688(12) 0.0500(10) 0.0653(11) 0.0009(8) 0.0377(10) -0.0301(9)
F2 0.0630(11) 0.0357(8) 0.0714(11) -0.0245(8) 0.0381(9) -0.0070(8)
F3 0.0359(8) 0.0606(11) 0.0585(10) -0.0228(8) 0.0185(7) -0.0163(7)
N1 0.0134(6) 0.0123(6) 0.0117(6) 0.0009(5) 0.0040(5) -0.0011(5)
N2 0.0128(6) 0.0128(6) 0.0101(6) -0.0008(5) 0.0036(5) -0.0001(5)
O1 0.0131(5) 0.0131(5) 0.0162(5) -0.0010(4) 0.0045(4) -0.0013(4)
O2 0.0137(5) 0.0124(5) 0.0155(5) 0.0008(4) 0.0044(4) -0.0010(4)
261
O3 0.0156(6) 0.0305(7) 0.0194(6) 0.0027(5) 0.0047(5) 0.0002(5)
O4 0.0164(6) 0.0306(7) 0.0183(6) -0.0045(5) 0.0044(5) -0.0021(5)
O5 0.0333(8) 0.0377(9) 0.0478(10) -0.0160(7) 0.0253(8) -0.0020(7)
O6 0.0485(10) 0.0386(10) 0.0489(10) 0.0043(8) 0.0322(9) -0.0030(8)
O7 0.0269(8) 0.0307(8) 0.0586(11) -0.0059(8) 0.0205(8) -0.0034(6)
P1 0.01594(19) 0.01153(18) 0.01182(17) -0.00096(14) 0.00646(15) -0.00045(14)
P2 0.01664(19) 0.01191(18) 0.01085(17) 0.00003(14) 0.00637(15) -0.00182(15)
Ru1 0.01200(6) 0.00994(6) 0.00990(6) -0.00032(4) 0.00501(4) -0.00088(4)
Ru2 0.01173(6) 0.00999(6) 0.00916(6) -0.00041(4) 0.00455(4) -0.00128(4)
S1 0.0266(2) 0.0233(2) 0.0399(3) -0.0067(2) 0.0222(2) -0.00507(19)
C36 0.041(3) 0.0277(18) 0.043(3) 0.0150(16) 0.0038(16) -0.0097(18)
Cl2 0.0381(5) 0.0548(6) 0.0382(4) 0.0126(4) 0.0170(4) 0.0118(4)
Cl3 0.0344(5) 0.0385(4) 0.0735(8) 0.0012(5) 0.0098(4) -0.0034(4)
C36' 0.041(3) 0.0277(18) 0.043(3) 0.0150(16) 0.0038(16) -0.0097(18)
Cl2' 0.0381(5) 0.0548(6) 0.0382(4) 0.0126(4) 0.0170(4) 0.0118(4)
Cl3' 0.0344(5) 0.0385(4) 0.0735(8) 0.0012(5) 0.0098(4) -0.0034(4)
Table A.41. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 4.6.
x/a y/b z/c U(eq)
H4A 0.5437 0.7299 0.5530 0.02
H4AB 0.5402 0.8234 0.5181 0.02
H5A 0.4995 0.7690 0.3825 0.028
H5AB 0.5037 0.6756 0.4177 0.028
H6A 0.6239 0.7031 0.3909 0.033
H6B 0.6482 0.6909 0.4877 0.033
H6C 0.6433 0.7834 0.4501 0.033
H4'A 0.5390 0.8297 0.5245 0.024
H4'B 0.5364 0.7619 0.5912 0.024
H5'A 0.5345 0.6521 0.4974 0.033
H5'B 0.6171 0.7069 0.5227 0.033
H6'A 0.5623 0.6833 0.3791 0.051
H6'B 0.5640 0.7818 0.3983 0.051
H6'C 0.4793 0.7305 0.3734 0.051
H7 0.3564 0.9229 0.3288 0.017
H8 0.3894 1.0455 0.2749 0.02
H9 0.3396 1.1752 0.3022 0.021
H10 0.2638 1.1787 0.3893 0.02
H12A 0.1654 1.0509 0.4422 0.018
H12B 0.2410 1.1014 0.5067 0.018
H14A 0.4238 0.9774 0.5394 0.029
H14B 0.4699 1.0329 0.6192 0.029
H14C 0.3913 1.0700 0.5469 0.029
262
H15A 0.3242 1.0991 0.6495 0.035
H15B 0.4078 1.0652 0.7172 0.035
H15C 0.3212 1.0265 0.7117 0.035
H16A 0.4032 0.8597 0.6283 0.034
H16B 0.3667 0.8819 0.6977 0.034
H16C 0.4554 0.9165 0.7052 0.034
H18A 0.1218 1.0638 0.5531 0.035
H18B 0.1946 1.0616 0.6411 0.035
H18C 0.1064 1.0228 0.6299 0.035
H19A 0.1596 0.8750 0.6767 0.038
H19B 0.2478 0.9198 0.7042 0.038
H19C 0.2297 0.8377 0.6474 0.038
H20A 0.0772 0.9373 0.4706 0.039
H20B 0.0558 0.8967 0.5442 0.039
H20C 0.1134 0.8470 0.5061 0.039
H21 0.3557 0.6352 0.3220 0.017
H22 0.3993 0.5169 0.2710 0.019
H23 0.3573 0.3830 0.2973 0.02
H24 0.2744 0.3720 0.3772 0.02
H26A 0.2383 0.4430 0.4889 0.018
H26B 0.1634 0.4928 0.4226 0.018
H28A 0.3887 0.6864 0.6199 0.039
H28B 0.4387 0.6306 0.6984 0.039
H28C 0.3477 0.6626 0.6854 0.039
H29A 0.3047 0.5163 0.6970 0.042
H29B 0.3937 0.4802 0.7075 0.042
H29C 0.3133 0.4445 0.6365 0.042
H30A 0.3880 0.4740 0.5434 0.032
H30B 0.4626 0.5188 0.6142 0.032
H30C 0.4141 0.5679 0.5306 0.032
H32A 0.0974 0.6872 0.4819 0.04
H32B 0.0385 0.6334 0.5152 0.04
H32C 0.0681 0.5954 0.4457 0.04
H33A 0.2015 0.7035 0.6254 0.042
H33B 0.2268 0.6225 0.6835 0.042
H33C 0.1342 0.6569 0.6528 0.042
H34A 0.1153 0.4703 0.5309 0.034
H34B 0.0903 0.5095 0.6029 0.034
H34C 0.1822 0.4765 0.6221 0.034
H36A -0.1095 0.6800 0.4395 0.049
H36B -0.1259 0.7744 0.4615 0.049
H36C -0.1267 0.6753 0.4608 0.049
263
H36D -0.1261 0.7752 0.4722 0.049
H1 0.2399(15) 0.7743(15) 0.4789(16) 0.027(6)
264
Crystal Structure of 5.2
An orange prism-like specimen of C
37
H
32
Cl
7
FeIrN
2
OP
2
, approximate dimensions 0.050 mm x 0.050
mm x 0.122 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured
on a Bruker APEX DUO system equipped with a fine-focus tube (MoKα, λ = 0.71073 Å) and a TRIUMPH
curved-crystal monochromator.
The frames were integrated with the Bruker SAINT software package using a SAINT V8.38A (Bruker
AXS, 2013) algorithm. The integration of the data using a monoclinic unit cell yielded a total of 99986
reflections to a maximum θ angle of 31.55° (0.68 Å resolution), of which 12805 were independent (average
redundancy 7.808, completeness = 95.4%, R
int
= 4.17%, R
sig
= 2.50%) and 11585 (90.47%) were greater
than 2σ(F
2
). The final cell constants of a = 9.706(3) Å, b = 16.933(4) Å, c = 24.815(6) Å, β = 100.009(4)°,
265
volume = 4016.3(18) Å
3
, are based upon the refinement of the XYZ-centroids of reflections above 20 σ(I).
Data were corrected for absorption effects using the multi-scan method (SADABS).
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/n 1, with Z = 4 for the formula unit, C
37
H
32
Cl
7
FeIrN
2
OP
2
. The final anisotropic full-matrix least-
squares refinement on F
2
with 509 variables converged at R1 = 2.36%, for the observed data and wR2 =
5.86% for all data. The goodness-of-fit was 1.043. The largest peak in the final difference electron density
synthesis was 0.792 e
-
/Å
3
and the largest hole was -1.041 e
-
/Å
3
with an RMS deviation of 0.105 e
-
/Å
3
. On
the basis of the final model, the calculated density was 1.784 g/cm
3
and F(000), 2112 e
-
.
Table A.42. Sample and crystal data for 5.2.
Chemical formula C
37
H
32
Cl
7
FeIrN
2
OP
2
Formula weight 1078.78 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.050 x 0.050 x 0.122 mm
Crystal habit orange prism
Crystal system monoclinic
Space group P 1 21/n 1
Unit cell dimensions a = 9.706(3) Å α = 90°
b = 16.933(4) Å β = 100.009(4)°
c = 24.815(6) Å γ = 90°
Volume 4016.3(18) Å
3
Z 4
Density (calculated) 1.784 g/cm
3
Absorption coefficient 4.250 mm
-1
F(000) 2112
Table A.43. Data collection and structure refinement for 5.2.
Diffractometer Bruker APEX DUO
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.46 to 31.55°
Index ranges -14<=h<=14, -23<=k<=24, -36<=l<=36
Reflections collected 99986
Independent reflections 12805 [R(int) = 0.0417]
Absorption correction multi-scan
Structure solution technique direct methods
266
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXTL XL 2017/1 (Bruker AXS, 2017)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 12805 / 13 / 509
Goodness-of-fit on F
2
1.043
Δ/σ
max
0.001
Final R indices 11585 data; I>2σ(I) R1 = 0.0236, wR2 = 0.0570
all data R1 = 0.0286, wR2 = 0.0586
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0243P)
2
+7.1070P]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 0.792 and -1.041 eÅ
-3
R.M.S. deviation from mean 0.105 eÅ
-3
Table A.44. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 5.2.
x/a y/b z/c U(eq)
C1 0.7901(2) 0.62978(13) 0.44865(9) 0.0136(4)
C2 0.5266(2) 0.48763(15) 0.25016(10) 0.0184(4)
C3 0.5031(3) 0.40828(15) 0.24003(10) 0.0200(5)
C4 0.5939(3) 0.35351(14) 0.26874(10) 0.0189(5)
C5 0.7021(3) 0.38165(14) 0.30838(10) 0.0167(4)
C6 0.7172(2) 0.46272(13) 0.31755(9) 0.0126(4)
C7 0.7781(2) 0.45005(13) 0.43172(9) 0.0119(4)
C8 0.6337(2) 0.45087(15) 0.43132(10) 0.0175(4)
C9 0.5792(3) 0.41599(16) 0.47391(10) 0.0208(5)
C10 0.6682(3) 0.38128(16) 0.51748(10) 0.0214(5)
C11 0.8115(3) 0.38184(16) 0.51836(10) 0.0208(5)
C12 0.8671(2) 0.41651(14) 0.47585(9) 0.0161(4)
C13 0.0111(2) 0.45340(13) 0.37199(9) 0.0116(4)
C14 0.1218(2) 0.50126(14) 0.36250(9) 0.0148(4)
C15 0.2500(2) 0.46842(15) 0.35696(11) 0.0189(5)
C16 0.2696(3) 0.38717(15) 0.36125(11) 0.0197(5)
C17 0.1604(3) 0.33880(14) 0.37158(10) 0.0182(4)
C18 0.0325(2) 0.37136(13) 0.37746(10) 0.0150(4)
C19 0.5377(2) 0.81871(14) 0.27151(9) 0.0161(4)
C20 0.5292(3) 0.90034(14) 0.26734(10) 0.0177(4)
C21 0.6320(3) 0.94593(14) 0.29841(10) 0.0188(5)
C22 0.7368(2) 0.90764(14) 0.33437(9) 0.0161(4)
C23 0.7370(2) 0.82528(13) 0.33735(9) 0.0125(4)
C24 0.7971(2) 0.80851(13) 0.45253(9) 0.0151(4)
C25 0.6534(3) 0.81628(17) 0.45150(10) 0.0223(5)
C26 0.6030(3) 0.83636(19) 0.49870(12) 0.0307(6)
267
x/a y/b z/c U(eq)
C27 0.6959(4) 0.84889(17) 0.54726(12) 0.0307(6)
C28 0.8385(3) 0.84040(17) 0.54889(11) 0.0281(6)
C29 0.8895(3) 0.81938(15) 0.50163(10) 0.0202(5)
C30 0.0283(2) 0.82080(13) 0.39370(9) 0.0135(4)
C31 0.0554(2) 0.89752(14) 0.41475(10) 0.0181(4)
C32 0.1852(3) 0.93246(15) 0.41540(11) 0.0222(5)
C33 0.2903(3) 0.89119(16) 0.39544(12) 0.0235(5)
C34 0.2653(2) 0.81525(15) 0.37503(11) 0.0202(5)
C35 0.1346(2) 0.78032(14) 0.37436(10) 0.0164(4)
Cl1 0.45530(6) 0.64322(3) 0.34725(3) 0.01989(11)
Cl2 0.56907(6) 0.66240(4) 0.19969(2) 0.02142(11)
Cl3 0.90013(6) 0.64590(3) 0.29233(2) 0.01370(9)
Fe1 0.63379(3) 0.64856(2) 0.29558(2) 0.01168(6)
Ir1 0.85233(2) 0.63678(2) 0.38305(2) 0.00924(3)
N1 0.6320(2) 0.51592(11) 0.28808(8) 0.0139(3)
N2 0.6403(2) 0.78060(11) 0.30518(8) 0.0133(3)
O1 0.7479(2) 0.62533(11) 0.48877(7) 0.0218(4)
P1 0.84410(6) 0.49980(3) 0.37624(2) 0.01023(10)
P2 0.85848(6) 0.77352(3) 0.39134(2) 0.01056(10)
C36 0.802(3) 0.6328(7) 0.1087(5) 0.057(6)
Cl4 0.8248(8) 0.5504(3) 0.0677(3) 0.0426(12)
Cl5 0.7777(6) 0.7203(4) 0.0706(4) 0.0465(12)
C36A 0.820(2) 0.6338(6) 0.1103(5) 0.029(3)
Cl4A 0.777(3) 0.5564(5) 0.0611(3) 0.071(3)
Cl5A 0.8032(18) 0.7270(5) 0.0785(5) 0.0519(19)
C37 0.2065(12) 0.6221(4) 0.2333(4) 0.0260(14)
Cl6 0.1751(8) 0.5479(3) 0.1825(4) 0.0251(5)
Cl7 0.1587(6) 0.71769(11) 0.2083(2) 0.0381(7)
C37A 0.214(4) 0.6388(10) 0.2305(12) 0.0260(14)
Cl6A 0.1763(13) 0.5495(6) 0.1950(3) 0.0251(5)
Cl7A 0.1164(19) 0.7146(4) 0.1923(8) 0.0381(7)
C37B 0.195(3) 0.6458(16) 0.2138(14) 0.0260(14)
Cl6B 0.188(4) 0.5518(15) 0.182(2) 0.0251(5)
Cl7B 0.0735(18) 0.7090(5) 0.1744(8) 0.0381(7)
Table A.45. Bond lengths (Å) for 5.2.
C1-O1 1.143(3) C1-Ir1 1.836(2)
C2-N1 1.352(3) C2-C3 1.379(3)
C2-H2 0.95 C3-C4 1.388(4)
C3-H3 0.95 C4-C5 1.392(3)
C4-H4 0.95 C5-C6 1.395(3)
268
C5-H5 0.95 C6-N1 1.349(3)
C6-P1 1.846(2) C7-C12 1.392(3)
C7-C8 1.400(3) C7-P1 1.823(2)
C8-C9 1.393(3) C8-H8 0.95
C9-C10 1.391(4) C9-H9 0.95
C10-C11 1.387(4) C10-H10 0.95
C11-C12 1.395(3) C11-H11 0.95
C12-H12 0.95 C13-C14 1.399(3)
C13-C18 1.408(3) C13-P1 1.821(2)
C14-C15 1.391(3) C14-H14 0.95
C15-C16 1.390(4) C15-H15 0.95
C16-C17 1.398(3) C16-H16 0.95
C17-C18 1.389(3) C17-H17 0.95
C18-H18 0.95 C19-N2 1.348(3)
C19-C20 1.388(3) C19-H19 0.95
C20-C21 1.385(4) C20-H20 0.95
C21-C22 1.391(3) C21-H21 0.95
C22-C23 1.397(3) C22-H22 0.95
C23-N2 1.353(3) C23-P2 1.845(2)
C24-C29 1.394(3) C24-C25 1.397(3)
C24-P2 1.823(2) C25-C26 1.388(3)
C25-H25 0.95 C26-C27 1.390(5)
C26-H26 0.95 C27-C28 1.385(5)
C27-H27 0.95 C28-C29 1.396(4)
C28-H28 0.95 C29-H29 0.95
C30-C35 1.392(3) C30-C31 1.408(3)
C30-P2 1.824(2) C31-C32 1.390(3)
C31-H31 0.95 C32-C33 1.396(4)
C32-H32 0.95 C33-C34 1.388(4)
C33-H33 0.95 C34-C35 1.397(3)
C34-H34 0.95 C35-H35 0.95
Cl1-Fe1 2.3293(8) Cl2-Fe1 2.3648(9)
Cl3-Ir1 2.3814(8) Cl3-Fe1 2.6007(9)
Fe1-N2 2.248(2) Fe1-N1 2.254(2)
Fe1-Ir1 2.7660(6) Ir1-P2 2.3243(8)
Ir1-P1 2.3261(8) C36-Cl5 1.753(10)
C36-Cl4 1.763(11) C36-H36A 0.99
C36-H36B 0.99 C36A-Cl5A 1.761(10)
C36A-Cl4A 1.792(10) C36A-H36C 0.99
C36A-H36D 0.99 C37-Cl7 1.766(6)
C37-Cl6 1.770(7) C37-H37A 0.99
C37-H37B 0.99 C37A-Cl6A 1.756(15)
269
C37A-Cl7A 1.771(16) C37A-H37C 0.99
C37A-H37D 0.99 C37B-Cl7B 1.758(17)
C37B-Cl6B 1.770(16) C37B-H37E 0.99
C37B-H37F 0.99
Table A.46. Bond angles (°) for 5.2.
O1-C1-Ir1 178.2(2) N1-C2-C3 123.6(2)
N1-C2-H2 118.2 C3-C2-H2 118.2
C2-C3-C4 119.1(2) C2-C3-H3 120.4
C4-C3-H3 120.4 C3-C4-C5 117.9(2)
C3-C4-H4 121.0 C5-C4-H4 121.0
C4-C5-C6 119.8(2) C4-C5-H5 120.1
C6-C5-H5 120.1 N1-C6-C5 122.1(2)
N1-C6-P1 117.55(16) C5-C6-P1 120.01(18)
C12-C7-C8 119.5(2) C12-C7-P1 122.11(17)
C8-C7-P1 118.21(17) C9-C8-C7 120.2(2)
C9-C8-H8 119.9 C7-C8-H8 119.9
C10-C9-C8 120.1(2) C10-C9-H9 119.9
C8-C9-H9 119.9 C11-C10-C9 119.7(2)
C11-C10-H10 120.2 C9-C10-H10 120.2
C10-C11-C12 120.6(2) C10-C11-H11 119.7
C12-C11-H11 119.7 C7-C12-C11 119.9(2)
C7-C12-H12 120.1 C11-C12-H12 120.1
C14-C13-C18 118.9(2) C14-C13-P1 118.54(17)
C18-C13-P1 122.55(17) C15-C14-C13 120.8(2)
C15-C14-H14 119.6 C13-C14-H14 119.6
C16-C15-C14 120.1(2) C16-C15-H15 120.0
C14-C15-H15 120.0 C15-C16-C17 119.7(2)
C15-C16-H16 120.2 C17-C16-H16 120.2
C18-C17-C16 120.5(2) C18-C17-H17 119.8
C16-C17-H17 119.8 C17-C18-C13 120.1(2)
C17-C18-H18 120.0 C13-C18-H18 120.0
N2-C19-C20 123.5(2) N2-C19-H19 118.3
C20-C19-H19 118.3 C21-C20-C19 119.0(2)
C21-C20-H20 120.5 C19-C20-H20 120.5
C20-C21-C22 118.2(2) C20-C21-H21 120.9
C22-C21-H21 120.9 C21-C22-C23 119.6(2)
C21-C22-H22 120.2 C23-C22-H22 120.2
N2-C23-C22 122.2(2) N2-C23-P2 116.94(16)
C22-C23-P2 120.50(17) C29-C24-C25 119.5(2)
C29-C24-P2 121.15(19) C25-C24-P2 119.01(18)
C26-C25-C24 120.3(3) C26-C25-H25 119.8
270
C24-C25-H25 119.8 C25-C26-C27 119.9(3)
C25-C26-H26 120.1 C27-C26-H26 120.1
C28-C27-C26 120.3(2) C28-C27-H27 119.9
C26-C27-H27 119.9 C27-C28-C29 120.0(3)
C27-C28-H28 120.0 C29-C28-H28 120.0
C24-C29-C28 120.0(3) C24-C29-H29 120.0
C28-C29-H29 120.0 C35-C30-C31 118.7(2)
C35-C30-P2 119.52(17) C31-C30-P2 121.76(17)
C32-C31-C30 120.5(2) C32-C31-H31 119.7
C30-C31-H31 119.7 C31-C32-C33 120.0(2)
C31-C32-H32 120.0 C33-C32-H32 120.0
C34-C33-C32 120.1(2) C34-C33-H33 120.0
C32-C33-H33 120.0 C33-C34-C35 119.8(2)
C33-C34-H34 120.1 C35-C34-H34 120.1
C30-C35-C34 120.9(2) C30-C35-H35 119.6
C34-C35-H35 119.6 Ir1-Cl3-Fe1 67.280(16)
N2-Fe1-N1 178.37(7) N2-Fe1-Cl1 89.44(5)
N1-Fe1-Cl1 90.63(5) N2-Fe1-Cl2 90.33(5)
N1-Fe1-Cl2 91.07(5) Cl1-Fe1-Cl2 117.70(3)
N2-Fe1-Cl3 90.61(5) N1-Fe1-Cl3 88.48(5)
Cl1-Fe1-Cl3 148.74(3) Cl2-Fe1-Cl3 93.56(2)
N2-Fe1-Ir1 89.14(5) N1-Fe1-Ir1 89.24(5)
Cl1-Fe1-Ir1 96.17(3) Cl2-Fe1-Ir1 146.12(2)
Cl3-Fe1-Ir1 52.574(19) C1-Ir1-P2 89.61(7)
C1-Ir1-P1 89.29(7) P2-Ir1-P1 178.897(19)
C1-Ir1-Cl3 172.16(7) P2-Ir1-Cl3 90.735(19)
P1-Ir1-Cl3 90.329(18) C1-Ir1-Fe1 112.03(7)
P2-Ir1-Fe1 90.112(15) P1-Ir1-Fe1 90.166(15)
Cl3-Ir1-Fe1 60.15(2) C6-N1-C2 117.3(2)
C6-N1-Fe1 128.73(15) C2-N1-Fe1 113.87(16)
C19-N2-C23 117.4(2) C19-N2-Fe1 113.98(15)
C23-N2-Fe1 128.52(15) C13-P1-C7 106.11(10)
C13-P1-C6 106.63(10) C7-P1-C6 99.49(10)
C13-P1-Ir1 114.51(7) C7-P1-Ir1 114.71(7)
C6-P1-Ir1 113.97(7) C24-P2-C30 104.75(11)
C24-P2-C23 100.97(10) C30-P2-C23 105.95(10)
C24-P2-Ir1 112.97(8) C30-P2-Ir1 116.69(8)
C23-P2-Ir1 113.93(7) Cl5-C36-Cl4 112.1(7)
Cl5-C36-H36A 109.2 Cl4-C36-H36A 109.2
Cl5-C36-H36B 109.2 Cl4-C36-H36B 109.2
H36A-C36-H36B 107.9 Cl5A-C36A-Cl4A 111.0(7)
Cl5A-C36A-H36C 109.4 Cl4A-C36A-H36C 109.4
271
Cl5A-C36A-H36D 109.4 Cl4A-C36A-H36D 109.4
H36C-C36A-H36D 108.0 Cl7-C37-Cl6 113.5(5)
Cl7-C37-H37A 108.9 Cl6-C37-H37A 108.9
Cl7-C37-H37B 108.9 Cl6-C37-H37B 108.9
H37A-C37-H37B 107.7 Cl6A-C37A-Cl7A 108.1(11)
Cl6A-C37A-H37C 110.1 Cl7A-C37A-H37C 110.1
Cl6A-C37A-H37D 110.1 Cl7A-C37A-H37D 110.1
H37C-C37A-H37D 108.4 Cl7B-C37B-Cl6B 109.2(17)
Cl7B-C37B-H37E 109.8 Cl6B-C37B-H37E 109.8
Cl7B-C37B-H37F 109.8 Cl6B-C37B-H37F 109.8
H37E-C37B-H37F 108.3
Table A.47. Torsion angles (°) for 5.2.
N1-C2-C3-C4 -2.1(4) C2-C3-C4-C5 2.7(4)
C3-C4-C5-C6 -0.8(4) C4-C5-C6-N1 -1.8(3)
C4-C5-C6-P1 171.43(18) C12-C7-C8-C9 -2.1(4)
P1-C7-C8-C9 -177.75(19) C7-C8-C9-C10 1.0(4)
C8-C9-C10-C11 0.2(4) C9-C10-C11-C12 -0.3(4)
C8-C7-C12-C11 2.0(3) P1-C7-C12-C11 177.46(19)
C10-C11-C12-C7 -0.8(4) C18-C13-C14-C15 1.8(3)
P1-C13-C14-C15 -177.69(18) C13-C14-C15-C16 -0.5(4)
C14-C15-C16-C17 -0.5(4) C15-C16-C17-C18 0.1(4)
C16-C17-C18-C13 1.2(4) C14-C13-C18-C17 -2.2(3)
P1-C13-C18-C17 177.31(18) N2-C19-C20-C21 1.2(4)
C19-C20-C21-C22 -2.7(3) C20-C21-C22-C23 1.2(3)
C21-C22-C23-N2 1.9(3) C21-C22-C23-P2 -171.08(18)
C29-C24-C25-C26 1.4(4) P2-C24-C25-C26 174.6(2)
C24-C25-C26-C27 0.1(5) C25-C26-C27-C28 -0.8(5)
C26-C27-C28-C29 0.2(4) C25-C24-C29-C28 -2.1(4)
P2-C24-C29-C28 -175.1(2) C27-C28-C29-C24 1.3(4)
C35-C30-C31-C32 1.0(4) P2-C30-C31-C32 -179.17(19)
C30-C31-C32-C33 -0.5(4) C31-C32-C33-C34 -0.1(4)
C32-C33-C34-C35 0.2(4) C31-C30-C35-C34 -0.9(3)
P2-C30-C35-C34 179.25(19) C33-C34-C35-C30 0.3(4)
C5-C6-N1-C2 2.5(3) P1-C6-N1-C2 -170.93(17)
C5-C6-N1-Fe1 179.33(16) P1-C6-N1-Fe1 5.9(3)
C3-C2-N1-C6 -0.5(4) C3-C2-N1-Fe1 -177.8(2)
C20-C19-N2-C23 1.8(3) C20-C19-N2-Fe1 -174.34(18)
C22-C23-N2-C19 -3.4(3) P2-C23-N2-C19 169.84(16)
C22-C23-N2-Fe1 172.15(16) P2-C23-N2-Fe1 -14.6(3)
C14-C13-P1-C7 -139.71(18) C18-C13-P1-C7 40.8(2)
C14-C13-P1-C6 114.90(18) C18-C13-P1-C6 -64.6(2)
272
C14-C13-P1-Ir1 -12.1(2) C18-C13-P1-Ir1 168.39(16)
C12-C7-P1-C13 28.6(2) C8-C7-P1-C13 -155.93(18)
C12-C7-P1-C6 139.10(19) C8-C7-P1-C6 -45.4(2)
C12-C7-P1-Ir1 -98.87(19) C8-C7-P1-Ir1 76.61(19)
N1-C6-P1-C13 -134.20(17) C5-C6-P1-C13 52.3(2)
N1-C6-P1-C7 115.71(18) C5-C6-P1-C7 -57.8(2)
N1-C6-P1-Ir1 -6.85(19) C5-C6-P1-Ir1 179.60(16)
C29-C24-P2-C30 -37.3(2) C25-C24-P2-C30 149.6(2)
C29-C24-P2-C23 -147.2(2) C25-C24-P2-C23 39.7(2)
C29-C24-P2-Ir1 90.7(2) C25-C24-P2-Ir1 -82.3(2)
C35-C30-P2-C24 145.16(19) C31-C30-P2-C24 -34.7(2)
C35-C30-P2-C23 -108.59(19) C31-C30-P2-C23 71.5(2)
C35-C30-P2-Ir1 19.4(2) C31-C30-P2-Ir1 -160.45(17)
N2-C23-P2-C24 -109.61(18) C22-C23-P2-C24 63.7(2)
N2-C23-P2-C30 141.42(17) C22-C23-P2-C30 -45.3(2)
N2-C23-P2-Ir1 11.78(19) C22-C23-P2-Ir1 -174.89(16)
Table A.48. Anisotropic atomic displacement parameters (Å
2
) for 5.2.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.0157(10) 0.0104(9) 0.0149(10) -0.0015(8) 0.0031(8) 0.0001(7)
C2 0.0131(10) 0.0209(11) 0.0198(11) -0.0055(9) -0.0010(8) 0.0023(8)
C3 0.0175(11) 0.0219(12) 0.0201(11) -0.0094(9) 0.0022(9) -0.0042(9)
C4 0.0225(12) 0.0158(11) 0.0196(11) -0.0060(9) 0.0068(9) -0.0059(9)
C5 0.0204(11) 0.0135(10) 0.0163(10) -0.0007(8) 0.0032(8) -0.0028(8)
C6 0.0131(9) 0.0131(10) 0.0121(9) -0.0027(7) 0.0039(7) -0.0026(7)
C7 0.0138(9) 0.0102(9) 0.0121(9) 0.0003(7) 0.0037(7) -0.0020(7)
C8 0.0143(10) 0.0202(11) 0.0182(11) 0.0012(9) 0.0035(8) -0.0001(8)
C9 0.0183(11) 0.0257(12) 0.0207(11) -0.0022(10) 0.0097(9) -0.0047(9)
C10 0.0259(12) 0.0241(12) 0.0164(11) 0.0009(9) 0.0094(9) -0.0053(10)
C11 0.0254(12) 0.0237(12) 0.0130(10) 0.0028(9) 0.0020(9) -0.0021(9)
C12 0.0169(10) 0.0178(10) 0.0133(10) 0.0022(8) 0.0017(8) 0.0002(8)
C13 0.0129(9) 0.0112(9) 0.0106(9) -0.0007(7) 0.0015(7) -0.0006(7)
C14 0.0137(10) 0.0131(10) 0.0170(10) 0.0008(8) 0.0010(8) -0.0016(8)
C15 0.0116(10) 0.0199(11) 0.0250(12) 0.0006(9) 0.0026(8) -0.0027(8)
C16 0.0146(10) 0.0200(11) 0.0243(12) -0.0015(9) 0.0031(9) 0.0026(8)
C17 0.0190(11) 0.0131(10) 0.0228(11) 0.0012(9) 0.0046(9) 0.0022(8)
C18 0.0163(10) 0.0121(10) 0.0172(10) -0.0001(8) 0.0046(8) -0.0007(8)
C19 0.0160(10) 0.0175(11) 0.0139(10) 0.0014(8) 0.0000(8) 0.0022(8)
C20 0.0198(11) 0.0181(11) 0.0150(10) 0.0024(8) 0.0027(8) 0.0056(8)
C21 0.0251(12) 0.0132(10) 0.0185(11) 0.0019(8) 0.0053(9) 0.0063(9)
C22 0.0197(11) 0.0116(10) 0.0167(10) -0.0017(8) 0.0024(8) 0.0012(8)
C23 0.0146(10) 0.0123(10) 0.0110(9) 0.0005(7) 0.0032(7) 0.0023(7)
273
U
11
U
22
U
33
U
23
U
13
U
12
C24 0.0214(11) 0.0117(10) 0.0130(10) -0.0002(8) 0.0047(8) 0.0019(8)
C25 0.0225(12) 0.0303(13) 0.0152(11) 0.0006(10) 0.0060(9) 0.0067(10)
C26 0.0344(15) 0.0378(16) 0.0235(13) 0.0033(12) 0.0155(11) 0.0135(12)
C27 0.0501(18) 0.0266(14) 0.0190(12) -0.0010(10) 0.0161(12) 0.0063(12)
C28 0.0483(17) 0.0223(13) 0.0123(11) -0.0024(9) 0.0018(11) -0.0052(12)
C29 0.0266(12) 0.0174(11) 0.0156(11) -0.0022(9) 0.0006(9) -0.0028(9)
C30 0.0132(9) 0.0118(10) 0.0150(10) 0.0014(8) 0.0008(8) -0.0015(7)
C31 0.0171(10) 0.0142(11) 0.0221(11) -0.0004(9) 0.0011(8) -0.0017(8)
C32 0.0204(12) 0.0147(11) 0.0292(13) 0.0002(9) -0.0024(10) -0.0043(9)
C33 0.0152(11) 0.0184(11) 0.0352(14) 0.0062(10) -0.0002(10) -0.0025(9)
C34 0.0125(10) 0.0193(11) 0.0286(13) 0.0046(10) 0.0029(9) 0.0010(8)
C35 0.0147(10) 0.0136(10) 0.0199(11) 0.0027(8) 0.0003(8) 0.0011(8)
Cl1 0.0230(3) 0.0165(3) 0.0236(3) -0.0016(2) 0.0135(2) -0.0024(2)
Cl2 0.0237(3) 0.0290(3) 0.0107(2) -0.0001(2) 0.0006(2) 0.0035(2)
Cl3 0.0154(2) 0.0147(2) 0.0117(2) 0.00073(17) 0.00420(17) 0.00027(17)
Fe1 0.01198(14) 0.01291(14) 0.00993(13) -0.00040(11) 0.00126(11) 0.00012(10)
Ir1 0.00973(4) 0.00896(4) 0.00900(4) 0.00002(3) 0.00158(3) -0.00011(3)
N1 0.0133(8) 0.0146(9) 0.0140(8) -0.0035(7) 0.0028(7) 0.0006(7)
N2 0.0130(8) 0.0143(9) 0.0126(8) 0.0010(7) 0.0024(7) 0.0011(7)
O1 0.0295(10) 0.0197(9) 0.0187(8) -0.0011(7) 0.0114(7) -0.0028(7)
P1 0.0113(2) 0.0093(2) 0.0102(2) 0.00014(18) 0.00213(18) -0.00089(18)
P2 0.0113(2) 0.0100(2) 0.0101(2) -0.00040(18) 0.00107(18) 0.00044(18)
C36 0.074(11) 0.068(10) 0.039(7) 0.039(6) 0.034(7) 0.035(7)
Cl4 0.059(3) 0.0386(13) 0.0325(16) 0.0121(10) 0.0157(13) -0.0032(12)
Cl5 0.0341(19) 0.045(2) 0.059(3) 0.0185(15) 0.0061(15) 0.0006(12)
C36A 0.028(4) 0.028(6) 0.033(7) -0.002(5) 0.007(4) 0.008(4)
Cl4A 0.125(9) 0.048(2) 0.0408(18) 0.0120(14) 0.014(3) -0.012(4)
Cl5A 0.082(4) 0.0324(18) 0.049(3) 0.0148(16) 0.034(3) 0.022(2)
C37 0.0230(19) 0.024(3) 0.030(2) -0.005(2) 0.0031(17) 0.004(3)
Cl6 0.0275(10) 0.0245(5) 0.0209(10) -0.0007(10) -0.0025(15) -0.0066(5)
Cl7 0.0396(15) 0.0236(4) 0.0570(16) 0.0071(7) 0.0251(14) 0.0039(7)
C37A 0.0230(19) 0.024(3) 0.030(2) -0.005(2) 0.0031(17) 0.004(3)
Cl6A 0.0275(10) 0.0245(5) 0.0209(10) -0.0007(10) -0.0025(15) -0.0066(5)
Cl7A 0.0396(15) 0.0236(4) 0.0570(16) 0.0071(7) 0.0251(14) 0.0039(7)
C37B 0.0230(19) 0.024(3) 0.030(2) -0.005(2) 0.0031(17) 0.004(3)
Cl6B 0.0275(10) 0.0245(5) 0.0209(10) -0.0007(10) -0.0025(15) -0.0066(5)
Cl7B 0.0396(15) 0.0236(4) 0.0570(16) 0.0071(7) 0.0251(14) 0.0039(7)
Table A.49. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 5.2.
x/a y/b z/c U(eq)
H2 0.4654 0.5245 0.2293 0.022
274
x/a y/b z/c U(eq)
H3 0.4256 0.3913 0.2137 0.024
H4 0.5827 0.2986 0.2616 0.023
H5 0.7654 0.3457 0.3291 0.02
H8 0.5728 0.4753 0.4019 0.021
H9 0.4810 0.4159 0.4732 0.025
H10 0.6310 0.3573 0.5465 0.026
H11 0.8723 0.3584 0.5482 0.025
H12 0.9654 0.4172 0.4770 0.019
H14 1.1094 0.5569 0.3598 0.018
H15 1.3242 0.5015 0.3502 0.023
H16 1.3569 0.3646 0.3572 0.024
H17 1.1738 0.2833 0.3746 0.022
H18 0.9594 0.3382 0.3852 0.018
H19 0.4676 0.7881 0.2495 0.019
H20 0.4539 0.9246 0.2435 0.021
H21 0.6310 1.0018 0.2953 0.023
H22 0.8077 0.9373 0.3567 0.019
H25 0.5899 0.8078 0.4183 0.027
H26 0.5052 0.8415 0.4978 0.037
H27 0.6615 0.8633 0.5794 0.037
H28 0.9016 0.8489 0.5822 0.034
H29 0.9872 0.8125 0.5029 0.024
H31 0.9844 0.9256 0.4286 0.022
H32 1.2025 0.9844 0.4294 0.027
H33 1.3790 0.9151 0.3958 0.028
H34 1.3368 0.7871 0.3615 0.024
H35 1.1181 0.7282 0.3605 0.02
H36A 0.7204 0.6238 0.1268 0.069
H36B 0.8859 0.6384 0.1377 0.069
H36C 0.7575 0.6309 0.1378 0.035
H36D 0.9175 0.6267 0.1296 0.035
H37A 0.1534 0.6092 0.2628 0.031
H37B 0.3072 0.6221 0.2495 0.031
H37C 0.3154 0.6504 0.2348 0.031
H37D 0.1885 0.6350 0.2673 0.031
H37E 0.1731 0.6408 0.2511 0.031
H37F 0.2905 0.6680 0.2168 0.031
275
Crystal Structure of 5.3
A pale green prism-like specimen of C
37
H
32
Cl
7
CoIrN
2
OP
2
, approximate dimensions 0.390 mm x 0.494
mm x 0.497 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured
on a Bruker APEX II CCD system equipped with a fine-focus tube (MoKα , λ = 0.71073 Å) and a TRIUMPH
curved-crystal monochromator.
The integration of the data using a monoclinic unit cell yielded a total of 30888 reflections to a
maximum θ angle of 27.48° (0.77 Å resolution), of which 9186 were independent (average redundancy
3.363, completeness = 99.9%, R
int
= 7.43%, R
sig
= 7.89%) and 7574 (82.45%) were greater than 2σ(F
2
). The
final cell constants of a = 21.731(7) Å, b = 12.688(4) Å, c = 15.533(5) Å, β = 108.649(4)°, volume = 4058.(2)
Å
3
, are based upon the refinement of the XYZ-centroids of 9599 reflections above 20 σ(I) with 5.037° < 2θ
< 55.09°. Data were corrected for absorption effects using the Numerical Mu From Formula method
(SADABS). The ratio of minimum to maximum apparent transmission was 0.037. The calculated minimum
and maximum transmission coefficients (based on crystal size) are 0.0001 and 0.0027.
276
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group C 1 c 1, with Z = 4 for the formula unit, C
37
H
32
Cl
7
CoIrN
2
OP
2
. The final anisotropic full-matrix least-
squares refinement on F
2
with 471 variables converged at R1 = 5.94%, for the observed data and wR2 =
15.36% for all data. The goodness-of-fit was 1.090. The largest peak in the final difference electron density
synthesis was 3.992 e
-
/Å
3
and the largest hole was -1.083 e
-
/Å
3
with an RMS deviation of 0.195 e
-
/Å
3
. On
the basis of the final model, the calculated density was 1.771 g/cm
3
and F(000), 2116 e
-
.
Table A.50. Sample and crystal data for 5.3.
Chemical formula C
37
H
32
Cl
7
CoIrN
2
OP
2
Formula weight 1081.86 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.390 x 0.494 x 0.497 mm
Crystal habit green prism
Crystal system monoclinic
Space group C 1 c 1
Unit cell dimensions a = 21.731(7) Å α = 90°
b = 12.688(4) Å β = 108.649(4)°
c = 15.533(5) Å γ = 90°
Volume 4058.(2) Å
3
Z 4
Density (calculated) 1.771 g/cm
3
Absorption coefficient 4.258 mm
-1
F(000) 2116
Table A.51. Data collection and structure refinement for 5.3.
Diffractometer Bruker APEX II CCD
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 1.89 to 27.48°
Index ranges -28<=h<=28, -16<=k<=16, -20<=l<=20
Reflections collected 30888
Independent reflections 9186 [R(int) = 0.0743]
Coverage of independent
reflections
99.9%
Absorption correction Numerical Mu From Formula
Max. and min. transmission 0.0027 and 0.0001
Structure solution technique direct methods
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
277
Refinement program SHELXTL XL 2018/3 (Bruker AXS, 2018)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 9186 / 421 / 471
Goodness-of-fit on F
2
1.090
Final R indices 7574 data; I>2σ(I) R1 = 0.0594, wR2 = 0.1377
all data R1 = 0.0786, wR2 = 0.1536
Weighting scheme
w=1/[σ
2
(F
o
2
)+(0.0520P)
2
+43.4173P]
where P=(F
o
2
+2F
c
2
)/3
Absolute structure parameter 0.040(14)
Largest diff. peak and hole 3.992 and -1.083 eÅ
-3
R.M.S. deviation from mean 0.195 eÅ
-3
Table A.52. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 5.3.
x/a y/b z/c U(eq)
C1 0.3712(9) 0.8609(15) 0.5973(13) 0.048(4)
C2 0.3629(11) 0.9282(16) 0.6642(14) 0.057(4)
C3 0.4134(12) 0.9840(17) 0.7162(15) 0.060(5)
C4 0.4738(10) 0.9760(15) 0.6995(13) 0.052(4)
C5 0.4788(8) 0.9089(14) 0.6325(10) 0.042(3)
C6 0.6209(8) 0.9400(12) 0.6983(11) 0.043(3)
C7 0.6267(9) 0.0453(13) 0.7275(12) 0.051(4)
C8 0.6782(9) 0.0751(15) 0.8021(12) 0.054(4)
C9 0.7244(10) 0.0012(14) 0.8462(13) 0.053(4)
C10 0.7186(9) 0.8997(14) 0.8184(12) 0.050(4)
C11 0.6679(7) 0.8679(14) 0.7446(11) 0.044(3)
C12 0.5457(9) 0.0049(14) 0.5217(14) 0.051(4)
C13 0.4862(10) 0.0618(14) 0.4810(13) 0.050(4)
C14 0.4851(11) 0.1421(16) 0.4198(14) 0.061(4)
C15 0.5394(12) 0.1652(16) 0.3952(13) 0.061(4)
C16 0.5957(13) 0.1119(17) 0.4342(15) 0.066(5)
C17 0.6001(10) 0.0337(15) 0.4964(14) 0.052(4)
C18 0.3834(10) 0.6145(16) 0.2950(12) 0.052(4)
C19 0.3838(10) 0.5458(17) 0.2250(13) 0.056(5)
C20 0.4344(10) 0.4796(16) 0.2330(12) 0.051(4)
C21 0.4859(10) 0.4859(14) 0.3126(12) 0.050(4)
C22 0.4847(8) 0.5529(13) 0.3791(11) 0.039(3)
C23 0.5299(8) 0.4530(13) 0.5526(11) 0.047(4)
C24 0.5757(10) 0.4204(13) 0.6328(11) 0.050(4)
C25 0.5611(10) 0.3396(14) 0.6843(13) 0.056(4)
C26 0.5008(9) 0.2917(15) 0.6559(13) 0.056(4)
C27 0.4540(10) 0.3271(14) 0.5770(12) 0.055(4)
C28 0.4695(9) 0.4072(13) 0.5260(12) 0.051(4)
278
x/a y/b z/c U(eq)
C29 0.6199(9) 0.5136(12) 0.4569(11) 0.046(3)
C30 0.6563(10) 0.5858(16) 0.4270(15) 0.060(5)
C31 0.7073(10) 0.5529(17) 0.3982(16) 0.067(5)
C32 0.7246(11) 0.4483(17) 0.4022(16) 0.067(5)
C33 0.6890(10) 0.3751(18) 0.4324(15) 0.067(5)
C34 0.6381(10) 0.4085(14) 0.4612(15) 0.059(5)
C35 0.5516(13) 0.7780(16) 0.4333(16) 0.041(5)
O1 0.5504(8) 0.8162(13) 0.3655(12) 0.042(4)
C35A 0.550(6) 0.701(6) 0.653(4) 0.041(5)
O1A 0.548(4) 0.656(5) 0.718(3) 0.042(4)
Cl1 0.5595(3) 0.6687(4) 0.6887(4) 0.0407(16)
Cl1A 0.5589(15) 0.799(2) 0.4008(17) 0.0407(16)
Cl2 0.3728(2) 0.8532(4) 0.3677(3) 0.0520(10)
Cl3 0.3597(2) 0.6206(4) 0.5177(3) 0.0464(9)
Co1 0.42801(10) 0.73405(17) 0.47614(13) 0.0352(4)
Ir1 0.55656(3) 0.73075(4) 0.54388(3) 0.03729(16)
N1 0.4288(7) 0.8495(11) 0.5835(9) 0.042(3)
N2 0.4343(7) 0.6201(12) 0.3717(10) 0.044(3)
P1 0.5530(2) 0.8991(3) 0.5998(3) 0.0394(9)
P2 0.5506(2) 0.5600(3) 0.4875(3) 0.0391(9)
C36 0.2831(12) 0.334(2) 0.2040(18) 0.078(7)
Cl4 0.3284(4) 0.2899(7) 0.3151(5) 0.093(2)
Cl5 0.2205(3) 0.2431(6) 0.1524(6) 0.0845(19)
C37 0.7798(12) 0.675(2) 0.6204(18) 0.073(6)
Cl6 0.7248(3) 0.6191(5) 0.6671(4) 0.0747(15)
Cl7 0.7542(4) 0.7927(6) 0.5628(5) 0.0870(19)
Table A.53. Bond lengths (Å) for 5.3.
C1-N1 1.34(2) C1-C2 1.40(3)
C1-H1 0.95 C2-C3 1.34(3)
C2-H2 0.95 C3-C4 1.42(3)
C3-H3 0.95 C4-C5 1.38(2)
C4-H4 0.95 C5-N1 1.34(2)
C5-P1 1.843(18) C6-C11 1.388(19)
C6-C7 1.404(19) C6-P1 1.829(16)
C7-C8 1.382(19) C7-H7 0.95
C8-C9 1.38(2) C8-H8 0.95
C9-C10 1.35(2) C9-H9 0.95
C10-C11 1.373(19) C10-H10 0.95
C11-H11 0.95 C12-C17 1.41(3)
C12-C13 1.44(2) C12-P1 1.782(19)
279
C13-C14 1.39(3) C13-H13 0.95
C14-C15 1.38(3) C14-H14 0.95
C15-C16 1.36(3) C15-H15 0.95
C16-C17 1.37(3) C16-H16 0.95
C17-H17 0.95 C18-N2 1.34(2)
C18-C19 1.40(3) C18-H18 0.95
C19-C20 1.36(3) C19-H19 0.95
C20-C21 1.38(3) C20-H20 0.95
C21-C22 1.34(2) C21-H21 0.95
C22-N2 1.37(2) C22-P2 1.830(17)
C23-C28 1.37(2) C23-C24 1.386(19)
C23-P2 1.833(17) C24-C25 1.40(2)
C24-H24 0.95 C25-C26 1.38(2)
C25-H25 0.95 C26-C27 1.39(2)
C26-H26 0.95 C27-C28 1.394(19)
C27-H27 0.95 C28-H28 0.95
C29-C30 1.39(2) C29-C34 1.387(19)
C29-P2 1.816(18) C30-C31 1.39(2)
C30-H30 0.95 C31-C32 1.38(2)
C31-H31 0.95 C32-C33 1.38(2)
C32-H32 0.95 C33-C34 1.38(2)
C33-H33 0.95 C34-H34 0.95
C35-O1 1.15(3) C35-Ir1 1.79(3)
C35A-O1A 1.17(4) C35A-Ir1 1.79(4)
Cl1-Ir1 2.365(5) Cl1A-Ir1 2.40(2)
Cl2-Co1 2.296(5) Cl3-Co1 2.304(5)
Co1-N2 2.209(15) Co1-N1 2.215(14)
Co1-Ir1 2.652(2) Ir1-P1 2.316(4)
Ir1-P2 2.324(4) C36-Cl5 1.77(2)
C36-Cl4 1.78(3) C36-H36A 0.99
C36-H36B 0.99 C37-Cl7 1.73(3)
C37-Cl6 1.74(3) C37-H37A 0.99
C37-H37B 0.99
Table A.54. Bond angles (°) for 5.3.
N1-C1-C2 122.1(18) N1-C1-H1 118.9
C2-C1-H1 118.9 C3-C2-C1 119.7(19)
C3-C2-H2 120.1 C1-C2-H2 120.1
C2-C3-C4 118.6(18) C2-C3-H3 120.7
C4-C3-H3 120.7 C5-C4-C3 118.9(18)
C5-C4-H4 120.5 C3-C4-H4 120.5
N1-C5-C4 122.1(17) N1-C5-P1 115.2(12)
280
C4-C5-P1 122.6(15) C11-C6-C7 119.0(15)
C11-C6-P1 120.6(12) C7-C6-P1 120.3(12)
C8-C7-C6 119.7(17) C8-C7-H7 120.2
C6-C7-H7 120.2 C7-C8-C9 119.7(17)
C7-C8-H8 120.2 C9-C8-H8 120.2
C10-C9-C8 120.6(18) C10-C9-H9 119.7
C8-C9-H9 119.7 C9-C10-C11 121.0(18)
C9-C10-H10 119.5 C11-C10-H10 119.5
C10-C11-C6 120.0(16) C10-C11-H11 120.0
C6-C11-H11 120.0 C17-C12-C13 117.7(18)
C17-C12-P1 119.1(14) C13-C12-P1 123.2(15)
C14-C13-C12 119.(2) C14-C13-H13 120.5
C12-C13-H13 120.5 C15-C14-C13 121.(2)
C15-C14-H14 119.5 C13-C14-H14 119.5
C16-C15-C14 120.(2) C16-C15-H15 120.0
C14-C15-H15 120.0 C15-C16-C17 122.(2)
C15-C16-H16 119.2 C17-C16-H16 119.2
C16-C17-C12 121.(2) C16-C17-H17 119.6
C12-C17-H17 119.6 N2-C18-C19 121.1(18)
N2-C18-H18 119.4 C19-C18-H18 119.4
C20-C19-C18 121.4(18) C20-C19-H19 119.3
C18-C19-H19 119.3 C19-C20-C21 116.6(18)
C19-C20-H20 121.7 C21-C20-H20 121.7
C22-C21-C20 121.0(18) C22-C21-H21 119.5
C20-C21-H21 119.5 C21-C22-N2 122.8(16)
C21-C22-P2 122.5(14) N2-C22-P2 114.7(12)
C28-C23-C24 119.2(16) C28-C23-P2 121.8(12)
C24-C23-P2 118.9(13) C23-C24-C25 120.2(18)
C23-C24-H24 119.9 C25-C24-H24 119.9
C26-C25-C24 120.4(18) C26-C25-H25 119.8
C24-C25-H25 119.8 C25-C26-C27 119.3(18)
C25-C26-H26 120.3 C27-C26-H26 120.3
C26-C27-C28 119.6(19) C26-C27-H27 120.2
C28-C27-H27 120.2 C23-C28-C27 121.3(17)
C23-C28-H28 119.3 C27-C28-H28 119.3
C30-C29-C34 117.8(17) C30-C29-P2 118.9(13)
C34-C29-P2 123.2(14) C29-C30-C31 120.7(19)
C29-C30-H30 119.6 C31-C30-H30 119.6
C32-C31-C30 121.(2) C32-C31-H31 119.7
C30-C31-H31 119.7 C31-C32-C33 119.(2)
C31-C32-H32 120.3 C33-C32-H32 120.3
C32-C33-C34 120.(2) C32-C33-H33 120.2
281
C34-C33-H33 120.2 C33-C34-C29 122.(2)
C33-C34-H34 119.2 C29-C34-H34 119.2
O1-C35-Ir1 174.3(18) O1A-C35A-Ir1 162.(7)
N2-Co1-N1 176.2(5) N2-Co1-Cl2 91.9(4)
N1-Co1-Cl2 89.6(4) N2-Co1-Cl3 89.6(4)
N1-Co1-Cl3 93.0(4) Cl2-Co1-Cl3 112.63(19)
N2-Co1-Ir1 88.7(4) N1-Co1-Ir1 87.6(4)
Cl2-Co1-Ir1 122.58(16) Cl3-Co1-Ir1 124.79(14)
C35A-Ir1-P1 79.(3) C35-Ir1-P1 93.0(6)
C35A-Ir1-P2 99.(3) C35-Ir1-P2 88.4(6)
P1-Ir1-P2 174.86(18) C35-Ir1-Cl1 178.2(9)
P1-Ir1-Cl1 86.80(17) P2-Ir1-Cl1 91.67(16)
C35A-Ir1-Cl1A 170.(3) P1-Ir1-Cl1A 91.5(6)
P2-Ir1-Cl1A 90.3(6) C35A-Ir1-Co1 89.(4)
C35-Ir1-Co1 83.2(8) P1-Ir1-Co1 88.67(13)
P2-Ir1-Co1 86.58(13) Cl1-Ir1-Co1 94.99(15)
Cl1A-Ir1-Co1 87.6(7) C5-N1-C1 118.4(15)
C5-N1-Co1 127.5(11) C1-N1-Co1 114.1(12)
C18-N2-C22 116.9(15) C18-N2-Co1 117.4(13)
C22-N2-Co1 125.7(11) C12-P1-C6 103.1(8)
C12-P1-C5 104.0(9) C6-P1-C5 107.1(8)
C12-P1-Ir1 116.4(7) C6-P1-Ir1 117.4(5)
C5-P1-Ir1 107.6(6) C29-P2-C22 102.3(8)
C29-P2-C23 105.9(8) C22-P2-C23 102.3(7)
C29-P2-Ir1 116.7(6) C22-P2-Ir1 109.0(6)
C23-P2-Ir1 118.5(6) Cl5-C36-Cl4 109.8(15)
Cl5-C36-H36A 109.7 Cl4-C36-H36A 109.7
Cl5-C36-H36B 109.7 Cl4-C36-H36B 109.7
H36A-C36-H36B 108.2 Cl7-C37-Cl6 114.7(14)
Cl7-C37-H37A 108.6 Cl6-C37-H37A 108.6
Cl7-C37-H37B 108.6 Cl6-C37-H37B 108.6
H37A-C37-H37B 107.6
Table A.55. Bond lengths (Å) for 5.3.
C1-N1 1.34(2) C1-C2 1.40(3)
C1-H1 0.95 C2-C3 1.34(3)
C2-H2 0.95 C3-C4 1.42(3)
C3-H3 0.95 C4-C5 1.38(2)
C4-H4 0.95 C5-N1 1.34(2)
C5-P1 1.843(18) C6-C11 1.388(19)
C6-C7 1.404(19) C6-P1 1.829(16)
C7-C8 1.382(19) C7-H7 0.95
282
C8-C9 1.38(2) C8-H8 0.95
C9-C10 1.35(2) C9-H9 0.95
C10-C11 1.373(19) C10-H10 0.95
C11-H11 0.95 C12-C17 1.41(3)
C12-C13 1.44(2) C12-P1 1.782(19)
C13-C14 1.39(3) C13-H13 0.95
C14-C15 1.38(3) C14-H14 0.95
C15-C16 1.36(3) C15-H15 0.95
C16-C17 1.37(3) C16-H16 0.95
C17-H17 0.95 C18-N2 1.34(2)
C18-C19 1.40(3) C18-H18 0.95
C19-C20 1.36(3) C19-H19 0.95
C20-C21 1.38(3) C20-H20 0.95
C21-C22 1.34(2) C21-H21 0.95
C22-N2 1.37(2) C22-P2 1.830(17)
C23-C28 1.37(2) C23-C24 1.386(19)
C23-P2 1.833(17) C24-C25 1.40(2)
C24-H24 0.95 C25-C26 1.38(2)
C25-H25 0.95 C26-C27 1.39(2)
C26-H26 0.95 C27-C28 1.394(19)
C27-H27 0.95 C28-H28 0.95
C29-C30 1.39(2) C29-C34 1.387(19)
C29-P2 1.816(18) C30-C31 1.39(2)
C30-H30 0.95 C31-C32 1.38(2)
C31-H31 0.95 C32-C33 1.38(2)
C32-H32 0.95 C33-C34 1.38(2)
C33-H33 0.95 C34-H34 0.95
C35-O1 1.15(3) C35-Ir1 1.79(3)
C35A-O1A 1.17(4) C35A-Ir1 1.79(4)
Cl1-Ir1 2.365(5) Cl1A-Ir1 2.40(2)
Cl2-Co1 2.296(5) Cl3-Co1 2.304(5)
Co1-N2 2.209(15) Co1-N1 2.215(14)
Co1-Ir1 2.652(2) Ir1-P1 2.316(4)
Ir1-P2 2.324(4) C36-Cl5 1.77(2)
C36-Cl4 1.78(3) C36-H36A 0.99
C36-H36B 0.99 C37-Cl7 1.73(3)
C37-Cl6 1.74(3) C37-H37A 0.99
C37-H37B 0.99
Table A.56. Anisotropic atomic displacement parameters (Å
2
) for 5.3.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.043(8) 0.058(10) 0.049(9) -0.003(7) 0.021(7) 0.003(7)
283
U
11
U
22
U
33
U
23
U
13
U
12
C2 0.061(10) 0.060(11) 0.059(11) 0.002(8) 0.031(8) 0.015(8)
C3 0.077(11) 0.063(12) 0.049(11) -0.012(8) 0.030(9) 0.012(8)
C4 0.059(9) 0.056(10) 0.039(9) -0.006(7) 0.014(8) 0.007(8)
C5 0.045(7) 0.053(9) 0.024(7) -0.001(6) 0.007(6) 0.009(6)
C6 0.044(8) 0.046(8) 0.038(8) -0.009(6) 0.011(6) -0.004(6)
C7 0.054(9) 0.046(8) 0.048(9) -0.010(7) 0.010(7) -0.001(7)
C8 0.058(10) 0.052(9) 0.047(9) -0.009(7) 0.010(7) -0.008(7)
C9 0.055(10) 0.064(9) 0.041(9) -0.009(7) 0.017(7) -0.003(7)
C10 0.051(9) 0.061(8) 0.042(8) -0.001(7) 0.019(7) 0.000(7)
C11 0.038(8) 0.050(8) 0.043(8) 0.000(6) 0.012(6) -0.004(6)
C12 0.041(9) 0.042(8) 0.069(13) 0.005(7) 0.016(8) 0.001(6)
C13 0.050(9) 0.049(9) 0.049(10) 0.003(7) 0.010(8) 0.008(7)
C14 0.076(11) 0.053(10) 0.045(10) 0.005(7) 0.006(9) 0.001(9)
C15 0.097(12) 0.047(10) 0.041(10) -0.002(7) 0.024(9) -0.010(8)
C16 0.090(12) 0.057(11) 0.060(12) 0.002(8) 0.037(11) -0.007(9)
C17 0.058(9) 0.050(9) 0.056(11) -0.003(7) 0.029(9) -0.004(7)
C18 0.053(9) 0.067(11) 0.035(8) 0.008(7) 0.012(6) 0.004(8)
C19 0.054(10) 0.070(12) 0.035(9) 0.001(7) 0.001(8) -0.004(8)
C20 0.058(10) 0.062(11) 0.031(7) -0.002(7) 0.012(7) -0.005(7)
C21 0.060(10) 0.047(9) 0.036(8) -0.004(6) 0.007(7) 0.003(8)
C22 0.043(7) 0.040(8) 0.035(7) 0.000(5) 0.013(6) -0.008(6)
C23 0.065(9) 0.036(8) 0.044(8) 0.005(6) 0.022(7) 0.008(6)
C24 0.065(10) 0.043(9) 0.041(8) 0.002(7) 0.017(7) 0.005(7)
C25 0.071(10) 0.052(10) 0.047(10) 0.012(7) 0.021(8) 0.013(8)
C26 0.076(10) 0.049(10) 0.050(9) 0.006(7) 0.029(8) 0.006(8)
C27 0.075(11) 0.046(9) 0.044(9) -0.001(7) 0.019(8) -0.004(8)
C28 0.065(9) 0.044(9) 0.043(9) 0.003(7) 0.017(7) 0.002(7)
C29 0.053(9) 0.049(8) 0.034(8) -0.006(6) 0.012(7) 0.008(7)
C30 0.073(12) 0.059(10) 0.057(12) 0.000(9) 0.031(10) 0.004(8)
C31 0.061(12) 0.082(11) 0.060(13) -0.001(11) 0.023(10) 0.004(10)
C32 0.057(12) 0.088(12) 0.054(13) -0.003(11) 0.014(10) 0.018(9)
C33 0.066(12) 0.070(11) 0.064(13) -0.008(10) 0.021(10) 0.021(9)
C34 0.064(11) 0.051(8) 0.062(12) -0.012(8) 0.021(9) 0.009(8)
C35 0.075(15) 0.026(9) 0.030(9) -0.006(6) 0.025(8) -0.002(8)
O1 0.063(10) 0.043(8) 0.025(8) 0.002(6) 0.020(7) -0.004(7)
C35A 0.075(15) 0.026(9) 0.030(9) -0.006(6) 0.025(8) -0.002(8)
O1A 0.063(10) 0.043(8) 0.025(8) 0.002(6) 0.020(7) -0.004(7)
Cl1 0.059(3) 0.037(3) 0.028(3) 0.000(2) 0.016(2) 0.000(2)
Cl1A 0.059(3) 0.037(3) 0.028(3) 0.000(2) 0.016(2) 0.000(2)
Cl2 0.064(3) 0.057(2) 0.039(2) 0.0147(18) 0.022(2) 0.011(2)
Cl3 0.051(2) 0.055(2) 0.0339(19) 0.0070(17) 0.0147(17) -0.0049(19)
284
U
11
U
22
U
33
U
23
U
13
U
12
Co1 0.0362(11) 0.0437(11) 0.0263(10) 0.0041(9) 0.0106(8) 0.0022(10)
Ir1 0.0453(3) 0.0362(3) 0.0308(3) -0.0019(4) 0.0127(2) 0.0003(4)
N1 0.040(6) 0.050(7) 0.036(7) 0.002(5) 0.015(5) 0.000(5)
N2 0.050(7) 0.049(8) 0.035(6) 0.000(6) 0.017(5) -0.004(6)
P1 0.049(2) 0.034(2) 0.036(2) -0.0024(16) 0.0148(19) 0.0024(17)
P2 0.050(2) 0.035(2) 0.029(2) -0.0054(15) 0.0092(17) 0.0000(17)
C36 0.059(13) 0.100(18) 0.082(17) -0.016(14) 0.033(12) -0.018(12)
Cl4 0.077(4) 0.108(6) 0.084(5) -0.015(4) 0.013(3) 0.014(4)
Cl5 0.069(4) 0.091(4) 0.092(5) -0.027(4) 0.022(3) -0.012(3)
C37 0.076(15) 0.078(15) 0.071(15) -0.014(12) 0.029(12) 0.004(12)
Cl6 0.082(4) 0.080(4) 0.065(3) -0.011(3) 0.026(3) -0.002(3)
Cl7 0.088(4) 0.080(4) 0.080(4) -0.001(3) 0.008(4) -0.008(3)
Table A.57. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 5.3.
x/a y/b z/c U(eq)
H1 0.3349 0.8221 0.5605 0.058
H2 0.3216 0.9342 0.6726 0.069
H3 0.4089 1.0281 0.7633 0.073
H4 0.5102 1.0163 0.7340 0.062
H7 0.5953 1.0960 0.6960 0.061
H8 0.6819 1.1459 0.8231 0.065
H9 0.7605 1.0221 0.8965 0.064
H10 0.7502 0.8497 0.8504 0.06
H11 0.6649 0.7965 0.7253 0.053
H13 0.4483 1.0446 0.4959 0.061
H14 0.4464 1.1818 0.3945 0.073
H15 0.5373 1.2181 0.3512 0.073
H16 0.6330 1.1295 0.4177 0.079
H17 0.6403 0.9984 0.5229 0.062
H18 0.3466 0.6580 0.2882 0.063
H19 0.3478 0.5453 0.1706 0.067
H20 0.4343 0.4315 0.1862 0.062
H21 0.5227 0.4420 0.3206 0.06
H24 0.6172 0.4531 0.6529 0.06
H25 0.5927 0.3174 0.7390 0.067
H26 0.4913 0.2353 0.6898 0.068
H27 0.4118 0.2968 0.5580 0.067
H28 0.4377 0.4305 0.4719 0.061
H30 0.6463 0.6588 0.4263 0.073
H31 0.7306 0.6032 0.3753 0.08
H32 0.7606 0.4265 0.3845 0.08
285
x/a y/b z/c U(eq)
H33 0.6994 0.3022 0.4334 0.08
H34 0.6151 0.3581 0.4844 0.071
H36A 0.2640 0.4043 0.2078 0.093
H36B 0.3122 0.3414 0.1666 0.093
H37A 0.8211 0.6883 0.6698 0.088
H37B 0.7889 0.6241 0.5779 0.088
286
Crystal Structure of 5.4
A red needle-like specimen of C
37
H
32
Cl
7
IrN
2
NiOP
2
, approximate dimensions 0.105 mm x 0.137 mm x
0.289 mm, was used for the X-ray crystallographic analysis. The X-ray intensity data were measured on a
Bruker APEX II CCD Bruker APEX DUO system equipped with a fine-focus tube (MoKα , λ = 0.71073 Å) and
a TRIUMPH curved-crystal monochromator.
The frames were integrated with the Bruker SAINT software package using a SAINT V8.40A (Bruker
AXS, 2013) algorithm. The integration of the data using a monoclinic unit cell yielded a total of 95672
reflections to a maximum θ angle of 29.57° (0.72 Å resolution), of which 11264 were independent (average
redundancy 8.494, completeness = 99.9%, R
int
= 6.42%, R
sig
= 3.55%) and 9735 (86.43%) were greater than
2σ(F
2
). The final cell constants of a = 9.717(4) Å, b = 16.846(6) Å, c = 24.683(9) Å, β = 99.673(6)°, volume =
3983.(2) Å
3
, are based upon the refinement of the XYZ-centroids of 9679 reflections above 20 σ(I) with
4.824° < 2θ < 60.58°. Data were corrected for absorption effects using the multi-scan method (SADABS).
287
The calculated minimum and maximum transmission coefficients (based on crystal size) are 0.0590 and
0.0998.
The structure was solved and refined using the Bruker SHELXTL Software Package, using the space
group P 1 21/n 1, with Z = 4 for the formula unit, C
37
H
32
Cl
7
IrN
2
NiOP
2
. The final anisotropic full-matrix least-
squares refinement on F
2
with 481 variables converged at R1 = 3.88%, for the observed data and wR2 =
9.03% for all data. The goodness-of-fit was 1.121. The largest peak in the final difference electron density
synthesis was 2.366 e
-
/Å
3
and the largest hole was -1.278 e
-
/Å
3
with an RMS deviation of 0.159 e
-
/Å
3
. On
the basis of the final model, the calculated density was 1.804 g/cm
3
and F(000), 2120 e
-
.
Table A.58. Sample and crystal data for 5.4.
Chemical formula C
37
H
32
Cl
7
IrN
2
NiOP
2
Formula weight 1081.64 g/mol
Temperature 100(2) K
Wavelength 0.71073 Å
Crystal size 0.105 x 0.137 x 0.289 mm
Crystal habit red needle
Crystal system monoclinic
Space group P 1 21/n 1
Unit cell dimensions a = 9.717(4) Å α = 90°
b = 16.846(6) Å β = 99.673(6)°
c = 24.683(9) Å γ = 90°
Volume 3983.(2) Å
3
Z 4
Density (calculated) 1.804 g/cm
3
Absorption coefficient 4.394 mm
-1
F(000) 2120
Table A.59. Data collection and structure refinement for 5.4.
Diffractometer Bruker APEX II CCD Bruker APEX DUO
Radiation source fine-focus tube (MoKα , λ = 0.71073 Å)
Theta range for data collection 2.15 to 29.57°
Index ranges -13<=h<=13, -23<=k<=23, -34<=l<=34
Reflections collected 95672
Independent reflections 11264 [R(int) = 0.0642]
Coverage of independent
reflections
99.9%
288
Absorption correction multi-scan
Max. and min. transmission 0.0998 and 0.0590
Structure solution technique direct methods
Structure solution program SHELXTL XT 2014/5 (Bruker AXS, 2014)
Refinement method Full-matrix least-squares on F
2
Refinement program SHELXL-2018/3 (Sheldrick, 2018)
Function minimized Σ w(F
o
2
- F
c
2
)
2
Data / restraints / parameters 11264 / 18 / 481
Goodness-of-fit on F
2
1.121
Δ/σ
max
0.002
Final R indices 9735 data; I>2σ(I) R1 = 0.0388, wR2 = 0.0851
all data R1 = 0.0500, wR2 = 0.0903
Weighting scheme
w=1/[σ
2
(F
o
2
)+36.4461P]
where P=(F
o
2
+2F
c
2
)/3
Largest diff. peak and hole 2.366 and -1.278 eÅ
-3
R.M.S. deviation from mean 0.159 eÅ
-3
Table A.60. Atomic coordinates and equivalent isotropic atomic displacement parameters (Å
2
) for 5.4.
x/a y/b z/c U(eq)
C1 0.5257(6) 0.4939(3) 0.2515(2) 0.0219(11)
C2 0.4998(6) 0.4137(3) 0.2400(2) 0.0228(11)
C3 0.5900(6) 0.3578(3) 0.2668(2) 0.0225(10)
C4 0.7004(6) 0.3836(3) 0.3062(2) 0.0197(10)
C5 0.7177(5) 0.4649(3) 0.3172(2) 0.0146(9)
C6 0.0113(5) 0.4518(3) 0.3712(2) 0.0158(9)
C7 0.1209(5) 0.5000(3) 0.3613(2) 0.0187(10)
C8 0.2496(6) 0.4676(3) 0.3564(2) 0.0229(11)
C9 0.2687(6) 0.3852(3) 0.3610(2) 0.0230(11)
C10 0.1606(6) 0.3370(3) 0.3704(2) 0.0216(11)
C11 0.0332(5) 0.3695(3) 0.3764(2) 0.0193(10)
C12 0.7780(5) 0.4485(3) 0.4314(2) 0.0146(9)
C13 0.8665(6) 0.4147(3) 0.4760(2) 0.0198(10)
C14 0.8111(6) 0.3807(3) 0.5187(2) 0.0243(11)
C15 0.6674(6) 0.3808(3) 0.5185(2) 0.0264(12)
C16 0.5796(6) 0.4146(4) 0.4746(2) 0.0257(12)
C17 0.6345(6) 0.4486(3) 0.4312(2) 0.0208(11)
C18 0.5360(5) 0.8118(3) 0.2726(2) 0.0186(10)
C19 0.5235(6) 0.8935(3) 0.2678(2) 0.0197(10)
C20 0.6250(6) 0.9410(3) 0.2978(2) 0.0214(11)
C21 0.7324(6) 0.9049(3) 0.3331(2) 0.0194(10)
C22 0.7370(5) 0.8223(3) 0.3371(2) 0.0164(9)
C23 0.7966(6) 0.8088(3) 0.4528(2) 0.0185(10)
289
x/a y/b z/c U(eq)
C24 0.6531(6) 0.8161(4) 0.4517(2) 0.0252(12)
C25 0.6029(8) 0.8370(4) 0.4989(3) 0.0386(16)
C26 0.6948(8) 0.8505(4) 0.5472(2) 0.0350(15)
C27 0.8370(8) 0.8424(4) 0.5491(2) 0.0311(13)
C28 0.8883(7) 0.8206(3) 0.5017(2) 0.0246(11)
C29 0.0282(5) 0.8206(3) 0.3929(2) 0.0158(9)
C30 0.1348(5) 0.7796(3) 0.3733(2) 0.0178(10)
C31 0.2652(6) 0.8143(3) 0.3739(2) 0.0235(11)
C32 0.2893(6) 0.8914(3) 0.3947(3) 0.0259(12)
C33 0.1854(6) 0.9326(3) 0.4141(2) 0.0252(12)
C34 0.0559(6) 0.8980(3) 0.4137(2) 0.0219(11)
C35 0.7909(5) 0.6288(3) 0.4496(2) 0.0181(9)
Cl1 0.89786(13) 0.64550(7) 0.29172(5) 0.0176(2)
Cl2 0.45083(15) 0.64323(8) 0.34113(6) 0.0256(3)
Cl3 0.57209(15) 0.66191(8) 0.20164(5) 0.0243(3)
Ir1 0.85265(2) 0.63583(2) 0.38346(2) 0.01277(5)
N1 0.6332(4) 0.5203(3) 0.28891(18) 0.0172(8)
N2 0.6421(4) 0.7750(3) 0.30523(18) 0.0157(8)
Ni1 0.64162(7) 0.64762(4) 0.29731(3) 0.01510(13)
O1 0.7484(4) 0.6244(2) 0.48994(16) 0.0261(9)
P1 0.84456(14) 0.49865(7) 0.37607(5) 0.0139(2)
P2 0.85938(14) 0.77272(7) 0.39148(5) 0.0144(2)
C36 0.8108(13) 0.6286(6) 0.1084(4) 0.051(3)
Cl4 0.7730(6) 0.7183(3) 0.0715(2) 0.0470(10)
Cl5 0.8149(8) 0.5473(2) 0.06421(18) 0.0582(13)
C36A 0.768(4) 0.6326(12) 0.1057(11) 0.051(3)
Cl4A 0.8150(14) 0.7256(9) 0.0807(7) 0.0470(10)
Cl5A 0.7487(19) 0.5539(8) 0.0590(6) 0.0582(13)
C37 0.2077(15) 0.6262(7) 0.2315(5) 0.029(3)
Cl6 0.1781(11) 0.5477(5) 0.1823(2) 0.0278(10)
Cl7 0.1410(6) 0.7165(2) 0.2031(2) 0.0525(12)
C37A 0.203(2) 0.6468(10) 0.2167(9) 0.029(3)
Cl6A 0.176(2) 0.5465(9) 0.1959(4) 0.0278(10)
Cl7A 0.0801(9) 0.7090(4) 0.1782(4) 0.0525(12)
Table A.61. Bond lengths (Å) for 5.4.
C1-N1 1.348(7) C1-C2 1.394(8)
C1-H1 0.95 C2-C3 1.378(8)
C2-H2 0.95 C3-C4 1.390(7)
C3-H3 0.95 C4-C5 1.402(7)
C4-H4 0.95 C5-N1 1.355(7)
290
C5-P1 1.831(5) C6-C7 1.392(7)
C6-C11 1.407(7) C6-P1 1.824(5)
C7-C8 1.389(7) C7-H7 0.95
C8-C9 1.402(8) C8-H8 0.95
C9-C10 1.378(8) C9-H9 0.95
C10-C11 1.384(7) C10-H10 0.95
C11-H11 0.95 C12-C17 1.394(7)
C12-C13 1.399(7) C12-P1 1.815(5)
C13-C14 1.385(7) C13-H13 0.95
C14-C15 1.396(8) C14-H14 0.95
C15-C16 1.385(8) C15-H15 0.95
C16-C17 1.397(8) C16-H16 0.95
C17-H17 0.95 C18-N2 1.347(6)
C18-C19 1.385(7) C18-H18 0.95
C19-C20 1.385(8) C19-H19 0.95
C20-C21 1.382(8) C20-H20 0.95
C21-C22 1.395(7) C21-H21 0.95
C22-N2 1.364(7) C22-P2 1.837(5)
C23-C28 1.389(8) C23-C24 1.395(8)
C23-P2 1.829(5) C24-C25 1.382(8)
C24-H24 0.95 C25-C26 1.383(10)
C25-H25 0.95 C26-C27 1.381(10)
C26-H26 0.95 C27-C28 1.395(8)
C27-H27 0.95 C28-H28 0.95
C29-C30 1.397(7) C29-C34 1.409(7)
C29-P2 1.824(5) C30-C31 1.393(7)
C30-H30 0.95 C31-C32 1.400(8)
C31-H31 0.95 C32-C33 1.376(8)
C32-H32 0.95 C33-C34 1.385(8)
C33-H33 0.95 C34-H34 0.95
C35-O1 1.143(6) C35-Ir1 1.834(5)
Cl1-Ir1 2.3837(14) Cl1-Ni1 2.5170(16)
Cl2-Ni1 2.2990(15) Cl3-Ni1 2.3569(16)
Ir1-P2 2.3146(15) Ir1-P1 2.3184(15)
Ir1-Ni1 2.7019(10) N1-Ni1 2.156(4)
N2-Ni1 2.155(4) C36-Cl5 1.756(10)
C36-Cl4 1.771(9) C36-H36A 0.99
C36-H36B 0.99 C36A-Cl5A 1.747(16)
C36A-Cl4A 1.772(16) C36A-H36C 0.99
C36A-H36D 0.99 C37-Cl7 1.753(10)
C37-Cl6 1.785(10) C37-H37A 0.99
C37-H37B 0.99 C37A-Cl7A 1.747(15)
291
C37A-Cl6A 1.772(14) C37A-H37C 0.99
C37A-H37D 0.99
Table A.62. Bond angles (°) for 5.4.
N1-C1-C2 123.4(5) N1-C1-H1 118.3
C2-C1-H1 118.3 C3-C2-C1 119.2(5)
C3-C2-H2 120.4 C1-C2-H2 120.4
C2-C3-C4 118.4(5) C2-C3-H3 120.8
C4-C3-H3 120.8 C3-C4-C5 119.6(5)
C3-C4-H4 120.2 C5-C4-H4 120.2
N1-C5-C4 122.0(5) N1-C5-P1 117.7(4)
C4-C5-P1 120.0(4) C7-C6-C11 118.9(5)
C7-C6-P1 118.3(4) C11-C6-P1 122.9(4)
C8-C7-C6 120.8(5) C8-C7-H7 119.6
C6-C7-H7 119.6 C7-C8-C9 119.4(5)
C7-C8-H8 120.3 C9-C8-H8 120.3
C10-C9-C8 120.2(5) C10-C9-H9 119.9
C8-C9-H9 119.9 C9-C10-C11 120.4(5)
C9-C10-H10 119.8 C11-C10-H10 119.8
C10-C11-C6 120.3(5) C10-C11-H11 119.9
C6-C11-H11 119.9 C17-C12-C13 119.1(5)
C17-C12-P1 118.7(4) C13-C12-P1 122.1(4)
C14-C13-C12 120.1(5) C14-C13-H13 120.0
C12-C13-H13 120.0 C13-C14-C15 120.9(5)
C13-C14-H14 119.5 C15-C14-H14 119.5
C16-C15-C14 119.1(5) C16-C15-H15 120.4
C14-C15-H15 120.4 C15-C16-C17 120.4(5)
C15-C16-H16 119.8 C17-C16-H16 119.8
C12-C17-C16 120.5(5) C12-C17-H17 119.8
C16-C17-H17 119.8 N2-C18-C19 123.7(5)
N2-C18-H18 118.1 C19-C18-H18 118.1
C18-C19-C20 119.0(5) C18-C19-H19 120.5
C20-C19-H19 120.5 C21-C20-C19 118.5(5)
C21-C20-H20 120.8 C19-C20-H20 120.8
C20-C21-C22 119.7(5) C20-C21-H21 120.1
C22-C21-H21 120.1 N2-C22-C21 122.0(5)
N2-C22-P2 116.6(4) C21-C22-P2 121.0(4)
C28-C23-C24 119.9(5) C28-C23-P2 120.8(4)
C24-C23-P2 118.9(4) C25-C24-C23 119.9(6)
C25-C24-H24 120.1 C23-C24-H24 120.1
C24-C25-C26 120.0(6) C24-C25-H25 120.0
C26-C25-H25 120.0 C27-C26-C25 120.7(6)
292
C27-C26-H26 119.6 C25-C26-H26 119.6
C26-C27-C28 119.5(6) C26-C27-H27 120.2
C28-C27-H27 120.2 C23-C28-C27 119.9(6)
C23-C28-H28 120.0 C27-C28-H28 120.0
C30-C29-C34 118.4(5) C30-C29-P2 119.4(4)
C34-C29-P2 122.1(4) C31-C30-C29 121.0(5)
C31-C30-H30 119.5 C29-C30-H30 119.5
C30-C31-C32 119.3(5) C30-C31-H31 120.4
C32-C31-H31 120.4 C33-C32-C31 120.5(5)
C33-C32-H32 119.8 C31-C32-H32 119.8
C32-C33-C34 120.3(5) C32-C33-H33 119.9
C34-C33-H33 119.9 C33-C34-C29 120.6(5)
C33-C34-H34 119.7 C29-C34-H34 119.7
O1-C35-Ir1 177.9(5) Ir1-Cl1-Ni1 66.85(3)
C35-Ir1-P2 89.84(16) C35-Ir1-P1 89.63(16)
P2-Ir1-P1 179.45(5) C35-Ir1-Cl1 171.67(17)
P2-Ir1-Cl1 90.35(4) P1-Ir1-Cl1 90.15(4)
C35-Ir1-Ni1 112.74(17) P2-Ir1-Ni1 90.05(4)
P1-Ir1-Ni1 90.01(3) Cl1-Ir1-Ni1 58.93(4)
C1-N1-C5 117.3(4) C1-N1-Ni1 113.9(4)
C5-N1-Ni1 128.7(3) C18-N2-C22 116.8(4)
C18-N2-Ni1 114.5(3) C22-N2-Ni1 128.7(3)
N2-Ni1-N1 177.99(16) N2-Ni1-Cl2 88.80(12)
N1-Ni1-Cl2 89.59(12) N2-Ni1-Cl3 89.14(12)
N1-Ni1-Cl3 90.30(13) Cl2-Ni1-Cl3 110.89(6)
N2-Ni1-Cl1 91.83(12) N1-Ni1-Cl1 90.13(12)
Cl2-Ni1-Cl1 155.32(6) Cl3-Ni1-Cl1 93.79(5)
N2-Ni1-Ir1 90.69(12) N1-Ni1-Ir1 90.80(12)
Cl2-Ni1-Ir1 101.12(5) Cl3-Ni1-Ir1 147.98(5)
Cl1-Ni1-Ir1 54.21(3) C12-P1-C6 106.3(2)
C12-P1-C5 100.1(2) C6-P1-C5 107.5(2)
C12-P1-Ir1 114.61(16) C6-P1-Ir1 114.67(17)
C5-P1-Ir1 112.40(17) C29-P2-C23 105.2(2)
C29-P2-C22 106.4(2) C23-P2-C22 100.8(2)
C29-P2-Ir1 117.07(17) C23-P2-Ir1 113.18(17)
C22-P2-Ir1 112.66(17) Cl5-C36-Cl4 111.7(6)
Cl5-C36-H36A 109.3 Cl4-C36-H36A 109.3
Cl5-C36-H36B 109.3 Cl4-C36-H36B 109.3
H36A-C36-H36B 107.9 Cl5A-C36A-Cl4A 116.5(15)
Cl5A-C36A-H36C 108.2 Cl4A-C36A-H36C 108.2
Cl5A-C36A-H36D 108.2 Cl4A-C36A-H36D 108.2
H36C-C36A-H36D 107.3 Cl7-C37-Cl6 111.4(7)
293
Cl7-C37-H37A 109.3 Cl6-C37-H37A 109.3
Cl7-C37-H37B 109.3 Cl6-C37-H37B 109.3
H37A-C37-H37B 108.0 Cl7A-C37A-Cl6A 111.0(12)
Cl7A-C37A-H37C 109.4 Cl6A-C37A-H37C 109.4
Cl7A-C37A-H37D 109.4 Cl6A-C37A-H37D 109.4
H37C-C37A-H37D 108.0
Table A.63. Anisotropic atomic displacement parameters (Å
2
) for 5.4.
U
11
U
22
U
33
U
23
U
13
U
12
C1 0.021(3) 0.022(3) 0.023(3) -0.003(2) 0.002(2) 0.000(2)
C2 0.021(3) 0.024(3) 0.022(3) -0.008(2) 0.001(2) -0.006(2)
C3 0.029(3) 0.018(2) 0.022(2) -0.005(2) 0.007(2) -0.007(2)
C4 0.026(3) 0.015(2) 0.018(2) 0.0009(18) 0.005(2) -0.0010(19)
C5 0.017(2) 0.013(2) 0.015(2) -0.0027(18) 0.0059(18) -0.0034(18)
C6 0.017(2) 0.017(2) 0.014(2) -0.0027(18) 0.0043(18) -0.0016(18)
C7 0.017(2) 0.017(2) 0.021(2) 0.0019(19) -0.0012(19) 0.0014(19)
C8 0.015(2) 0.022(3) 0.032(3) 0.000(2) 0.003(2) -0.002(2)
C9 0.019(2) 0.021(3) 0.029(3) 0.000(2) 0.002(2) 0.003(2)
C10 0.025(3) 0.015(2) 0.026(3) 0.003(2) 0.007(2) 0.002(2)
C11 0.021(2) 0.015(2) 0.023(2) 0.002(2) 0.0063(19) 0.000(2)
C12 0.016(2) 0.013(2) 0.016(2) -0.0002(17) 0.0032(18) -0.0002(17)
C13 0.020(2) 0.021(2) 0.018(2) 0.001(2) 0.0027(19) 0.001(2)
C14 0.031(3) 0.023(3) 0.018(2) 0.005(2) 0.004(2) -0.002(2)
C15 0.035(3) 0.025(3) 0.021(3) 0.003(2) 0.011(2) -0.006(2)
C16 0.022(3) 0.029(3) 0.028(3) -0.003(2) 0.010(2) -0.002(2)
C17 0.018(2) 0.026(3) 0.018(2) 0.001(2) 0.0009(19) -0.001(2)
C18 0.017(2) 0.020(2) 0.019(2) 0.001(2) 0.0017(19) 0.0011(19)
C19 0.022(3) 0.019(2) 0.018(2) 0.0008(19) 0.003(2) 0.004(2)
C20 0.026(3) 0.019(2) 0.020(2) 0.001(2) 0.007(2) 0.002(2)
C21 0.020(2) 0.017(2) 0.022(3) -0.002(2) 0.005(2) 0.002(2)
C22 0.019(2) 0.017(2) 0.014(2) 0.0001(18) 0.0033(18) 0.0021(19)
C23 0.025(3) 0.016(2) 0.015(2) 0.0017(19) 0.005(2) 0.003(2)
C24 0.027(3) 0.032(3) 0.017(2) 0.001(2) 0.008(2) 0.006(2)
C25 0.045(4) 0.044(4) 0.033(3) 0.006(3) 0.024(3) 0.019(3)
C26 0.061(4) 0.027(3) 0.021(3) 0.000(2) 0.020(3) 0.006(3)
C27 0.049(4) 0.026(3) 0.018(3) -0.002(2) 0.005(3) -0.004(3)
C28 0.033(3) 0.019(3) 0.021(3) -0.001(2) 0.003(2) -0.003(2)
C29 0.016(2) 0.016(2) 0.015(2) 0.0003(18) -0.0004(18) 0.0007(18)
C30 0.017(2) 0.016(2) 0.020(2) 0.0033(19) 0.0001(19) 0.0018(19)
C31 0.016(2) 0.022(3) 0.033(3) 0.003(2) 0.004(2) 0.003(2)
C32 0.016(2) 0.023(3) 0.037(3) 0.007(2) -0.001(2) -0.004(2)
C33 0.028(3) 0.016(2) 0.030(3) 0.000(2) 0.001(2) -0.004(2)
294
U
11
U
22
U
33
U
23
U
13
U
12
C34 0.023(3) 0.019(2) 0.022(3) 0.001(2) 0.001(2) -0.001(2)
C35 0.023(2) 0.014(2) 0.018(2) -0.0020(19) 0.0053(19) -0.002(2)
Cl1 0.0208(5) 0.0170(5) 0.0158(5) 0.0006(4) 0.0054(4) -0.0006(4)
Cl2 0.0293(6) 0.0188(6) 0.0329(7) -0.0035(5) 0.0170(5) -0.0036(5)
Cl3 0.0281(7) 0.0295(7) 0.0143(5) -0.0004(5) 0.0010(5) 0.0030(5)
Ir1 0.01376(8) 0.01195(8) 0.01257(8) -0.00006(7) 0.00217(6) 0.00002(7)
N1 0.016(2) 0.017(2) 0.019(2) -0.0033(17) 0.0039(16) -0.0019(16)
N2 0.0140(19) 0.016(2) 0.018(2) 0.0002(16) 0.0033(16) 0.0004(16)
Ni1 0.0165(3) 0.0147(3) 0.0140(3) -0.0005(2) 0.0022(2) -0.0002(2)
O1 0.033(2) 0.025(2) 0.0238(19) -0.0007(16) 0.0148(17) -0.0027(17)
P1 0.0148(6) 0.0137(5) 0.0132(6) 0.0001(4) 0.0020(5) -0.0010(5)
P2 0.0151(6) 0.0139(5) 0.0141(6) -0.0002(5) 0.0022(5) 0.0008(5)
C36 0.059(9) 0.049(5) 0.054(5) 0.030(4) 0.037(6) 0.038(5)
Cl4 0.035(2) 0.0435(15) 0.064(2) 0.0206(15) 0.013(2) 0.0090(18)
Cl5 0.087(4) 0.0464(14) 0.0465(15) 0.0101(11) 0.026(2) -0.007(2)
C36A 0.059(9) 0.049(5) 0.054(5) 0.030(4) 0.037(6) 0.038(5)
Cl4A 0.035(2) 0.0435(15) 0.064(2) 0.0206(15) 0.013(2) 0.0090(18)
Cl5A 0.087(4) 0.0464(14) 0.0465(15) 0.0101(11) 0.026(2) -0.007(2)
C37 0.027(3) 0.030(7) 0.031(7) -0.003(5) 0.005(5) -0.001(5)
Cl6 0.0312(9) 0.0259(8) 0.024(3) 0.004(2) -0.002(3) -0.0046(6)
Cl7 0.067(3) 0.0271(12) 0.076(3) 0.0106(19) 0.047(2) 0.0090(18)
C37A 0.027(3) 0.030(7) 0.031(7) -0.003(5) 0.005(5) -0.001(5)
Cl6A 0.0312(9) 0.0259(8) 0.024(3) 0.004(2) -0.002(3) -0.0046(6)
Cl7A 0.067(3) 0.0271(12) 0.076(3) 0.0106(19) 0.047(2) 0.0090(18)
Table A.64. Hydrogen atomic coordinates and isotropic atomic displacement parameters (Å
2
) for 5.4.
x/a y/b z/c U(eq)
H1 0.4643 0.5320 0.2319 0.026
H2 0.4210 0.3979 0.2141 0.027
H3 0.5772 0.3029 0.2585 0.027
H4 0.7636 0.3462 0.3255 0.024
H7 1.1074 0.5558 0.3579 0.022
H8 1.3240 0.5009 0.3499 0.028
H9 1.3564 0.3626 0.3577 0.028
H10 1.1736 0.2811 0.3728 0.026
H11 0.9602 0.3360 0.3841 0.023
H13 0.9647 0.4151 0.4770 0.024
H14 0.8718 0.3571 0.5485 0.029
H15 0.6303 0.3579 0.5482 0.032
H16 0.4816 0.4146 0.4739 0.031
H17 0.5735 0.4721 0.4014 0.025
295
x/a y/b z/c U(eq)
H18 0.4656 0.7799 0.2518 0.022
H19 0.4465 0.9166 0.2443 0.024
H20 0.6210 0.9972 0.2942 0.026
H21 0.8027 0.9362 0.3545 0.023
H24 0.5900 0.8067 0.4185 0.03
H25 0.5052 0.8420 0.4982 0.046
H26 0.6598 0.8656 0.5794 0.042
H27 0.8994 0.8517 0.5824 0.037
H28 0.9858 0.8138 0.5029 0.029
H30 1.1182 0.7273 0.3594 0.021
H31 1.3369 0.7861 0.3604 0.028
H32 1.3780 0.9154 0.3953 0.031
H33 1.2026 0.9849 0.4280 0.03
H34 0.9850 0.9267 0.4275 0.026
H36A 0.9023 0.6334 0.1328 0.061
H36B 0.7389 0.6192 0.1318 0.061
H36C 0.8405 0.6176 0.1374 0.061
H36D 0.6793 0.6392 0.1197 0.061
H37A 0.1626 0.6130 0.2634 0.035
H37B 0.3092 0.6318 0.2447 0.035
H37C 0.1966 0.6517 0.2561 0.035
H37D 0.2982 0.6634 0.2119 0.035

Abstract (if available)

Abstract This thesis focuses on organometallic chemistry of iridium and ruthenium complexes that enable synthetically and economically important catalytic hydrogen transfer reactions, such as coupling of amines and alcohols, acceptorless dehydrogenation of primary alcohols to carboxylic acids, and dehydrogenation of formic acid. The general strategy of the research projects is concerned with analysis of catalyst evolution mechanisms that involve precatalytic, catalytic, and post catalytic steps. Understanding the underlying processes of homogeneous catalytic reactions is important for the design of synthetically crucial transformations. On the other hand, this type of research benefits the organometallic chemistry of platinum group metals. ❧ Chapter one reviews traditional and modern methods for the direct oxidation of primary alcohols to carboxylic acids. Within the last seven years, a great number of new methods have emerged that utilize transition metal compounds as catalysts for acceptorless dehydrogenation of alcohols to carboxylates. The interest in this reaction is explained by its atom economy, which is in accord with the principles of sustainability and green chemistry. This chapter introduces the reader to our catalytic system for acceptorless dehydrogenation of alcohols. ❧ Chapter two describes the first iridium-based catalytic system for the conversion of primary alcohols to potassium carboxylates (or carboxylic acids) in the presence of potassium hydroxide using either [Ir(2-PyCH₂(C₄H₅N₂))(COD)]⁺ or [Ir(PN)(COD)]⁺ (PN = 2-PyCH₂PBuᵗ₂). The method provides both aliphatic and aromatic carboxylates in high yield and with outstanding functional group tolerance. The application of this method to a diverse variety of primary alcohols, including heterocyclic and amino alcohols was illustrated. Complex [Ir(PN)(COD)]⁺ reacts with alcohols to form the crystallographically characterized catalytic intermediates [IrH(η¹,η³-C₈H₁₂)(PN)] and [Ir₂H₃(CO)(PN)(μ-PN)]. Synthetic studies on several of the iridium intermediates supported a general proposal of the mechanism of catalyst activation that enables the alcohol dehydrogenation. ❧ Chapter three presents a study on evolution of complex [Ir(PN)(COD)]⁺ in a catalytic dehydrogenation of neat formic acid. The complex undergoes multiple transformations and gives a series of derivatives, including structurally characterized precatalytic intermediate [Ir₂H₃(μ-OOCH)₂(PN)₂]⁺ and a dehydrogenated form of the active catalyst [Ir₂H(CO)₂(PN)₂]⁺. Elaborate time-course NMR studies suggest a slow carbonylation of iridium at high temperature as a key step for generating the active catalyst that can dehydrogenate formic acid even at room temperature. ❧ Chapter four describes the mechanism, scope, and catalyst evolution for ruthenium-based coupling of amines and alcohols, which proceeds from a [RuCl(PN)(η⁶-cymene)]⁺ precatalyst. The method selectively produces secondary amines through a hydrogen borrowing mechanism and is successfully applied to several heterocyclic substrates. Under the reaction conditions, precatalyst evolves through a series of catalytic intermediates: [RuH(PN)(η⁶-cymene)]⁺, [Ru₃H₂Cl₂(CO)(PN)₂(μ-PN)]⁺, and a diastereomeric pair of [Ru₂HCl(CO)₂(PN)₂(μ-O₂CPrⁿ)]⁺. A study of catalytic activity shows that [Ru₃H₂Cl₂(CO)(PN)₂(μ-PN)]⁺ is a dormant form of the catalyst, whereas the pair of [Ru₂HCl(CO)₂(PN)₂(μ-O₂CPrⁿ)]⁺ are the ultimate dead forms. Factors that govern the formation of the catalytic intermediates and the role of selective ruthenium carbonylation, which is essential for enabling generation of the active catalyst were discussed. ❧ Chapter five is devoted to the synthesis and study of three complexes based on Ir–M (M = Feᴵᴵ, Coᴵᴵ, and Niᴵᴵ) heterobimetallic core and 2-(diphenylphosphino)pyridine (Ph₂PPy) ligand. Their structures were established by single-crystal X-ray diffraction as [Ir(CO)(μ-Cl)(μ-Ph₂PPy)₂FeCl₂], [IrCl(CO)(μ-Ph₂PPy)₂CoCl₂], and [Ir(CO)(μ-Cl)(μ-Ph₂PPy)₂NiCl₂]. Time-dependent DFT computations suggest a donor-acceptor interaction between a filled 5dz² orbital on iridium and an empty orbital on the first-row metal atom, which is supported by UV-vis studies. Magnetic moment measurements show that the first-row metals are in their high-spin electronic configurations. Cyclic voltammetry data show that all the complexes undergo irreversible decomposition upon either reduction or oxidation. While these complexes are not stable to electrocatalysis conditions, the data presented here refine the understanding of the bonding synergies of the first-row and third-row metals.

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University of Southern California Dissertations and Theses

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Asset Metadata

Creator Cherepakhin, Valeriy (author)

Core Title Hydrogen transfer reactions catalyzed by iridium and ruthenium complexes

School College of Letters, Arts and Sciences

Degree Doctor of Philosophy

Degree Program Chemistry

Publication Date 11/15/2020

Defense Date 10/29/2020

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag acceptorless dehydrogenation,alcohol,amine,carboxylic acid,catalysis,formic acid,iridium,mechanism,OAI-PMH Harvest,ruthenium

Language English

Contributor Electronically uploaded by the author (provenance)

Advisor Williams, Travis Jesse (committee chair), Feakins, Sarah (committee member), Thompson, Barry (committee member)

Creator Email cherepak@usc.edu,valcherrypack@gmail.com

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c89-391378

Unique identifier UC11665821

Identifier etd-Cherepakhi-9122.pdf (filename),usctheses-c89-391378 (legacy record id)

Legacy Identifier etd-Cherepakhi-9122.pdf

Dmrecord 391378

Document Type Dissertation

Rights Cherepakhin, Valeriy

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the a...

Repository Name University of Southern California Digital Library

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