Topics in Organometallic ChemistryAlso Available Electronically 7
Aims and Scope 7
Preface 9
Contents 11
Five-Coordinate Platinum(IV) Complexes 13
1 Introduction 14
2 Proposed Five-Coordinate Platinum(IV) Intermediates 16
2.1 Reductive Elimination from Pt(IV) 16
2.1.1 C-C Reductive Elimination 16
2.1.2 C-X Reductive Elimination 18
2.1.3 C-H Reductive Elimination 19
2.2 beta-Hydrogen Elimination from Pt(IV) 21
2.3 Five-Coordinate Rh(III) and Ir(III) Complexes 22
3 First Isolable Five-Coordinate Pt(IV) Complexes 23
4 Survey of Known Five-Coordinate Pt(IV) Complexes 24
5 Reactivity of Five-Coordinate Platinum(IV) Complexes 27
5.1 Coordination of Monodentate Ligands 28
5.2 Reductive Elimination 29
5.3 Metal-Ligand Cooperativity 33
6 Conclusions and Future Directions 36
References 36
The Role of Higher Oxidation State Species in Platinum-Mediated C-H Bond Activation and Functionalization 40
1 Introduction 41
2 Formation and Decomposition of RPt(IV) in the Shilov System 42
2.1 Conversion of RPt(II) to RPt(IV) 43
2.2 Formation of R-X from RPt(IV) 46
3 Does C-H Activation in the Shilov System Involve Pt(IV) Intermediates? 47
3.1 Studies on Protonolysis of R-Pt(II) 48
3.2 Computational Studies on the Shilov System 53
4 Pt(IV) in Alkane Activation and Functionalization by Ligand-Substituted Complexes 54
4.1 The Catalytica System 54
4.2 Stoichiometric C-H Activation at Ligated Pt(II) 57
4.3 Oxidation by Dioxygen 62
5 Conclusions and Prospects 66
References 68
Carbon-Heteroatom Bond-Forming Reductive Elimination from Palladium(IV) Complexes 71
1 Introduction 72
2 Mechanistic Considerations 72
3 Carbon-Chalcogen Bond Formation 73
3.1 Carbon-Chalcogen Bond-Forming Reactions in Oxidative Pd Catalysis 73
3.2 C-S and C-Se Bond Formation 74
3.3 C-O Bond Formation 76
4 Carbon-Halogen Bond Formation 81
4.1 Carbon-Halogen Bond-Forming Reactions in Oxidative Pd Catalysis 81
4.2 C-I Bond Formation 82
4.3 C-Br Bond Formation 84
4.4 C-Cl Bond Formation 85
4.5 C-F Bond Formation 87
5 Conclusions and Future Directions 91
References 92
Palladium(IV) Complexes as Intermediates in Catalytic and Stoichiometric Cascade Sequences Providing Complex Carbocycles and Heterocycles 95
1 Introduction 96
2 Processes Catalytic in Palladium 96
3 Processes Stoichiometric in Palladium 102
3.1 Oxidative Addition Reactions of Palladacyclopentanes 102
3.2 Synthesis of 1,3-Dienes from Palladacyclopentadienes 103
3.3 Norbornene-Derived Palladacycles 104
3.4 Synthesis of Benzoxepines, Benzopyrans, and Benzofurans from Oxapalladacycles 106
3.4.1 Intermediates on the Pathway from Oxapalladacycles to Benzoxepines, Benzopyrans, and Benzofurans 106
3.4.2 Spectroscopic and Crystallograhic Characterization of the Palladium(IV) Intermediates 113
4 Concluding Remarks 118
References 119
eta1-Alkynyl Chemistry for the Higher Oxidation States of Palladium and Platinum 120
1 Introduction 121
2 Bis(eta1-alkynyl)metal Chemistry 121
3 Mono(eta1-alkynyl)metal Chemistry 124
4 Mono(eta1-alkynyl)metal Chemistry Derived from Iodonium Reagents 127
5 Concluding Remarks 133
References 134
Palladium(III) in Synthesis and Catalysis 137
1 Introduction 138
2 Mononuclear Pd(III) Chemistry 138
2.1 Mononuclear Pd(III) Werner-Type Complexes 138
2.2 Mononuclear Pd(III) Complexes in Catalysis 139
2.2.1 Pd(III) in Pd-Catalyzed Oxidative C-H Coupling Reactions 139
2.2.2 Pd(III) in Pd-Catalyzed Oxidative Carbon-Heteroatom Bond-Forming Reactions 143
2.2.3 Pd(III) in Kumada and Negishi Coupling Reactions 144
2.2.4 Pd(III) Intermediates in O2 Insertion Reactions 145
2.3 Organometallic Chemistry of Isolated Pd(III) Complexes 146
3 Dinuclear Pd(III) Chemistry 148
3.1 Dinuclear Pd(III) Complexes 148
3.1.1 Dinuclear Pd(II) Complexes 148
3.1.2 Pd(II)/Pd(III) Mixed Valence Complexes 149
3.1.3 Dinuclear Pd(III) Complexes 151
3.2 Dinuclear Pd(III) Complexes in Catalysis 152
3.2.1 Pd-Catalyzed C-H Acetoxylation 152
3.2.2 Pd-Catalyzed C-H Chlorination 153
3.2.3 Pd-Catalyzed C-H Arylation 155
3.3 Role of Dinuclear Core During Redox Chemistry 157
3.3.1 Discussion of High-Valent Pd Intermediates Relevant in Pd-Catalyzed C-H Oxidations 159
4 Outlook 160
References 161
Organometallic Platinum(II) and Palladium(II) Complexes as Donor Ligands for Lewis-Acidic d10 and s2 Centers 165
1 Introduction 166
2 General Considerations 167
2.1 Nature of the Donor and Acceptor Moieties 167
2.2 Binding Modes 167
2.3 Synthesis 168
2.4 Characterization 168
3 Alkyl Complexes 169
3.1 Methyl Complexes 169
3.1.1 Methylplatinum(II) Complexes 169
3.1.2 Methylpalladium(II) Complexes 171
3.2 Metallacycles 172
4 Aryl Complexes 172
4.1 Metallacycles 172
4.1.1 Platinacycles 173
4.1.2 Palladacycles 175
4.2 Perhalophenyl Complexes 175
4.2.1 Discrete Polymetallic Structures 176
4.2.2 Extended Structures Incorporating Thallium(I) 178
4.3 Phenyl Complexes 178
5 Alkynyl Complexes 181
5.1 Tetraalkynylplatinates 181
5.2 Diphosphine-bridged Complexes 182
6 Carbene Complexes 183
6.1 Platinum 183
6.2 Palladium 184
7 Reactivity 185
7.1 Electron Transfer Reactions 186
7.2 Ligand Migration Reactions 188
7.2.1 Halide Migration 188
7.2.2 Hydrocarbyl Migration 189
8 Perspectives 189
References 190
Index 193