Science of Synthesis Knowledge Updates 2015 Vol. 1 (eBook)

Martin Oestreich, Christopher A. Ramsden, Thomas Wirth (Herausgeber)

eBook Download: PDF

2015 | 1. Auflage
524 Seiten
Thieme (Verlag)
978-3-13-176381-5 (ISBN)

Infos

The Science of Synthesis Editorial Board, together with the volume editors and authors, is constantly reviewing the whole field of synthetic organic chemistry as presented in Science of Synthesis and evaluating significant developments in synthetic methodology. Four annual volumes updating content across all categories ensure that you always have access to state-of-the-art synthetic methodology.

Inhalt

Science of Synthesis: Knowledge Updates 2015/1 1
Title Page 
7 
Imprint 8
Preface 9
Abstracts 11
Overview 17
Table of Contents 19
4.4.4.8 Silyl Hydrides (Update 2015) 29
4.4.4.8.1 Synthesis of Silyl Hydrides 30
4.4.4.8.1.1 Method 1: From Inorganic Silanes 30
4.4.4.8.1.2 Method 2: From Alkyl- or Arylsilanes 32
4.4.4.8.1.3 Method 3: From Silyl Halides 36
4.4.4.8.1.4 Method 4: From Silyl Ethers 38
4.4.4.8.1.5 Method 5: From Other Silyl Hydrides by Monohalogenation or Deuterium Exchange 41
4.4.4.8.2 Applications of Silyl Hydrides in Organic Synthesis 44
4.4.4.8.2.1 Method 1: Hydrosilylation of Alkenes, Alkynes, and Related Compounds 44
4.4.4.8.2.2 Method 2: Silyl Hydrides as Reducing Agents 58
4.4.4.8.2.3 Method 3: Dehydrogenative Silylation 71
4.4.34.35 Vinylsilanes (Update 2015) 87
4.4.34.35.1 Vinylmetal Addition to Silane Electrophiles 88
4.4.34.35.1.1 Method 1: Addition to Chlorosilanes 88
4.4.34.35.1.2 Method 2: Addition to Cyclic Siloxanes 91
4.4.34.35.2 Hydrosilylation of Alkynes 93
4.4.34.35.2.1 Method 1: Transition-Metal-Catalyzed b-Hydrosilylation of Terminal Alkynes To Give e-Vinylsilanes 93
4.4.34.35.2.1.1 Variation 1: PlatinumCatalysis 93
4.4.34.35.2.1.2 Variation 2: Rhodium Catalysis 98
4.4.34.35.2.1.3 Variation 3: Palladium Catalysis 101
4.4.34.35.2.1.4 Variation 4: Iridium Catalysis 101
4.4.34.35.2.2 Method 2: Transition-Metal-Catalyzed b-Hydrosilylation of Terminal Alkynes To GiveZ- 102
4.4.34.35.2.2.1 Variation 1: RutheniumCatalysis 102
4.4.34.35.2.2.2 Variation 2: Rhodium Catalysis 103
4.4.34.35.2.2.3 Variation 3: Iridium Catalysis 104
4.4.34.35.2.3 Method 3: Transition-Metal-Catalyzed a-Hydrosilylation of Terminal Alkynes 105
4.4.34.35.2.3.1 Variation 1: Ruthenium Catalysis 105
4.4.34.35.2.3.2 Variation 2: Platinum Catalysis 107
4.4.34.35.2.4 Method 4: Transition-Metal-Catalyzed syn Hydrosilylation of Internal Alkynes 108
4.4.34.35.2.4.1 Variation 1: Platinum Catalysis 108
4.4.34.35.2.4.2 Variation 2: Palladium Catalysis 111
4.4.34.35.2.5 Method 5: Transition-Metal-Catalyzed anti Hydrosilylation of Internal Alkynes 112
4.4.34.35.2.6 Method 6: Lewis Acid Catalyzed Hydrosilylation 114
4.4.34.35.2.7 Method 7: Radical Hydrosilylation 115
4.4.34.35.3 Silylmetalation of Alkynes 115
4.4.34.35.3.1 Method 1: Silylcupration 116
4.4.34.35.3.1.1 Variation 1: Silylcupration Using Silyllithium Reagents 116
4.4.34.35.3.1.2 Variation 2: Silylcupration Using Silylboronic Ester Reagents 117
4.4.34.35.3.2 Method 2: Copper-Catalyzed Silylmetalation 122
4.4.34.35.3.3 Method 3: Silylzincation 123
4.4.34.35.3.4 Method 4: Silylrhodation 123
4.4.34.35.4 Addition to Alkynylsilanes 125
4.4.34.35.4.1 Method 1: Hydrogenation 126
4.4.34.35.4.2 Method 2: Hydrometalation 126
4.4.34.35.4.2.1 Variation 1: Hydrometalation Followed by Protodemetalation 126
4.4.34.35.4.2.2 Variation 2: Hydrometalation Followed by Halogenation 128
4.4.34.35.4.2.3 Variation 3: Hydrometalation Followed by Alkylation 129
4.4.34.35.4.3 Method 3: Carbometalation 132
4.4.34.35.5 Intermolecular Coupling of Alkynylsilanes 132
4.4.34.35.5.1 Method 1: Ruthenium-Catalyzed Alder-Ene Reaction 132
4.4.34.35.5.2 Method 2: Reductive Coupling 136
4.4.34.35.5.3 Method 3: Enyne Cross Metathesis 140
4.4.34.35.6 Ring-Closing Metathesis of a-Substituted Vinylsilanes 141
4.4.34.35.7 Dehydrogenative Silylation of Alkenes 143
4.4.34.35.7.1 Method 1: Reaction with Silanes 143
4.4.34.35.7.2 Method 2: Reaction with Halosilanes or Silyl Trifluoromethanesulfonates 144
4.4.34.35.7.3 Method 3: Transfer Silylation 146
4.4.34.35.7.4 Method 4: Reaction with Siletanes 146
4.4.34.35.8 Carbometalation of Vinylsilanes 147
4.4.34.35.8.1 Method 1: Heck Reaction with Aryl Halides 147
4.4.34.35.8.2 Method 2: Heck-Type Reaction with Benzonitriles 149
4.4.34.35.8.3 Method 3: Iron-Catalyzed Oxidative Arylation 150
4.4.34.35.9 Addition to Carbonyl Compounds 150
4.4.34.35.9.1 Method 1: Reaction with (Dihalomethyl)silane Reagents 150
4.4.34.35.9.2 Method 2: Reaction with DisilylmethyllithiumReagents 151
4.4.34.35.9.3 Method 3: Reaction with (Halomethyl)silane Reagents 152
4.4.34.35.9.4 Method 4: Reaction with (a-Silylallyl)borane Reagents 154
4.4.34.35.10 Rearrangements 155
4.4.34.35.10.1 Method 1: Gold-Catalyzed Rearrangement of Allyl(alkynyl)silanes 156
4.4.34.35.10.2 Method 2: Rearrangement of (a-Hydroxypropargyl)silanes 157
4.4.34.35.10.3 Method 3: Rearrangement of Silyl Allenoates 158
4.4.34.35.11 Synthesis of Cyclic Vinylsilanes 159
4.4.34.35.11.1 Method 1: Intramolecular Hydrosilylation of Alkynes 159
4.4.34.35.11.1.1 Variation 1: Metal-Catalyzed syn-exo Hydrosilylation 159
4.4.34.35.11.1.2 Variation 2: Metal-Catalyzed anti-exo Hydrosilylation 160
4.4.34.35.11.1.3 Variation 3: Metal-Catalyzed endo-Hydrosilylation 161
4.4.34.35.11.1.4 Variation 4: Base-Promoted Hydrosilylation 163
4.4.34.35.11.2 Method 2: Cyclization of Vinylsilanes 164
4.4.34.35.11.2.1 Variation 1: By Ring-Closing Metathesis with Terminal Vinylsilanes 165
4.4.34.35.11.2.2 Variation 2: By Silylvinylation 166
4.4.34.35.11.3 Method 3: Cyclization of Alkynylsilanes 167
4.4.34.35.11.3.1 Variation 1: By Ring-Closing Enyne Metathesis 167
4.4.34.35.11.3.2 Variation 2: By Reductive Coupling of Alkynylsilanes 168
4.4.34.35.11.3.3 Variation 3: By Gold-Catalyzed Cyclization 169
4.4.34.35.11.3.4 Variation 4: By Semihydrogenation 170
4.4.34.35.11.4 Method 4: Three-Component Coupling 172
4.4.34.35.11.5 Method 5: Ring Contraction of Cyclic Vinylsilanes 173
4.4.34.35.12 Synthesis from Acylsilanes 174
4.4.34.35.13 Synthesis fromAllenes 176
4.4.34.35.13.1 Method 1: Hydrosilylation 177
4.4.34.35.13.2 Method 2: Silylmetalation 178
31.1.2 Fluoroarenes (Update 2015) 187
31.1.2.1 Synthesis of Fluoroarenes 188
31.1.2.1.1 Synthesis by Substitution of Hydrogen 188
31.1.2.1.1.1 Method 1: Reaction with Hydrogen Fluoride–Pyridine Complex 188
31.1.2.1.1.2 Method 2: Reaction with Silver(II) Fluoride 189
31.1.2.1.1.3 Method 3: Reaction with Fluorinating Agents Mediated by Transition-Metal Catalysts 190
31.1.2.1.2 Synthesis by Substitution of Organometallic Groups 191
31.1.2.1.2.1 Method 1: Substitution of Boronic Acids and Esters 192
31.1.2.1.2.1.1 Variation 1: Reaction with Silver(I) Trifluoromethanesulfonate and Selectfluor 192
31.1.2.1.2.1.2 Variation 2: Reaction with Acetyl Hypofluorite 193
31.1.2.1.2.1.3 Variation 3: Palladium-Catalyzed Fluorodeboronation 193
31.1.2.1.2.1.4 Variation 4: Copper-Catalyzed Fluorodeboronation 195
31.1.2.1.3 Synthesis by Substitution of Halogens 195
31.1.2.1.3.1 Method 1: Reaction with Anhydrous Tetrabutylammonium Fluoride 196
31.1.2.1.3.2 Method 2: Reactions Catalyzed by Transition Metals 196
31.1.2.1.3.2.1 Variation 1: Palladium-Catalyzed Reactions 196
31.1.2.1.3.2.2 Variation 2: Copper-Catalyzed Reactions 197
31.1.2.1.4 Synthesis by Substitution of Nitrogen 198
31.1.2.1.5 Synthesis by Substitution of Oxygen 198
31.1.2.1.5.1 Method 1: Palladium-Catalyzed Displacement of Trifluoromethanesulfonate by Cesium Fluoride 198
31.1.2.1.5.2 Method 2: Deoxyfluorination Using PhenoFluor 200
31.2.3 Chloroarenes (Update 2015) 203
31.2.3.1 Synthesis of Chloroarenes 203
31.2.3.1.1 Synthesis by Substitution 203
31.2.3.1.1.1 Method 1: Electrophilic Chlorination 203
31.2.3.1.1.1.1 Variation 1: Of Phenols and Anisoles 203
31.2.3.1.1.1.2 Variation 2: Of Anilines, Acetanilides, and Related Compounds 206
31.2.3.1.1.1.3 Variation 3: Of Benzene and Alkylbenzene Derivatives 207
31.2.3.1.1.1.4 Variation 4: Of Electron-Deficient Benzene Derivatives 208
31.2.3.1.1.2 Method 2: Substitution of Boron 209
31.2.3.1.1.3 Method 3: Substitution of Bromine 210
31.2.3.1.2 Synthesis by Addition–Elimination 212
31.2.3.2 Applications of Chloroarenes in Organic Synthesis 212
31.2.3.2.1 Method 1: Cross-Coupling Reactions 212
31.2.3.2.1.1 Variation 1: Synthesis of Biaryls 212
31.2.3.2.1.2 Variation 2: Synthesis of Arylalkenes 221
31.2.3.2.1.3 Variation 3: Synthesis of Arylalkynes 225
31.2.3.2.1.4 Variation 4: Synthesis of Arylalkanes 227
31.2.3.2.1.5 Variation 5: Carbonylation and Cyanation Reactions 228
31.2.3.2.1.6 Variation 6: Metal-Catalyzed Heterosubstitution Reactions 229
31.3.3 Bromoarenes (Update 2015) 235
31.3.3.1 Synthesis of Bromoarenes 235
31.3.3.1.1 Synthesis by Substitution 235
31.3.3.1.1.1 Method 1: Electrophilic Bromination 235
31.3.3.1.1.1.1 Variation 1: Of Phenols and Anisoles 235
31.3.3.1.1.1.2 Variation 2: Of Anilines, Acetanilides, and Related Compounds 240
31.3.3.1.1.1.3 Variation 3: Of Benzene and Alkylbenzene Derivatives 242
31.3.3.1.1.1.4 Variation 4: Of Electron-Deficient Benzene Derivatives 243
31.3.3.1.1.1.5 Variation 5: Of Arylboronates 245
31.3.3.1.1.2 Method 2: Synthesis from Organometallics 245
31.3.3.1.1.2.1 Variation 1: From Arylboronates 245
31.3.3.1.1.3 Method 3: Substitution of a Trifluoromethanesulfonate Group 246
31.3.3.2 Applications of Bromoarenes in Organic Synthesis 247
31.3.3.2.1 Method 1: Cross-Coupling Reactions 247
31.3.3.2.1.1 Variation 1: Synthesis of Biaryls 247
31.3.3.2.1.2 Variation 2: Synthesis of Arylalkenes 250
31.3.3.2.1.3 Variation 3: Synthesis of Arylalkynes 251
31.3.3.2.1.4 Variation 4: Synthesis of Arylalkanes 252
31.3.3.2.1.5 Variation 5: Carbonylation and Cyanation Reactions 253
31.3.3.2.1.6 Variation 6: Metal-Catalyzed Heterosubstitution Reactions 255
31.3.3.2.1.7 Variation 7: Borylation Reactions 255
31.3.3.2.1.8 Variation 8: Phosphonylation Reactions 256
31.3.3.2.1.9 Variation 9: Transhalogenation Reactions 257
31.3.3.2.2 Method 2: Hydrodebromination Reactions 257
31.4.1.3 Hypervalent Iodoarenes and Aryliodonium Salts (Update 2015) 261
31.4.1.3.1 Synthesis of Hypervalent Iodoarenes and Aryliodonium Salts 261
31.4.1.3.1.1 Synthesis by Oxidative Addition to Iodoarenes 261
31.4.1.3.1.1.1 Method 1: Iodylarenes by Oxidation of Iodoarenes 261
31.4.1.3.1.1.1.1 Variation 1: Acyclic Iodylarenes 262
31.4.1.3.1.1.1.2 Variation 2: Cyclic Iodylarenes 263
31.4.1.3.1.1.1.3 Variation 3: Polymer-Supported Iodylarenes 264
31.4.1.3.1.1.2 Method 2: (Difluoroiodo)arenes by Fluorination of Iodoarenes 264
31.4.1.3.1.1.2.1 Variation 1: (Difluoroiodo)arenes by One-Pot Synthesis from Arenes 265
31.4.1.3.1.1.3 Method 3: (Dichloroiodo)arenes by Chlorination of Iodoarenes 266
31.4.1.3.1.1.4 Method 4: [Bis(acyloxy)iodo]arenes by Oxidation of Iodoarenes in the Presence of a Carboxylic Acid 268
31.4.1.3.1.1.5 Method 5: Aryliodine(III) Sulfonates by Oxidation of Iodoarenes in the Presence of a Sulfonic Acid 269
31.4.1.3.1.2 Synthesis by Ligand Exchange of Hypervalent Iodine Compounds 270
31.4.1.3.1.2.1 Method 1: 1-Oxo-1-(tosyloxy)-1H-1l5-benzo[d][1,2]iodoxol-3-one from 2-Iodoxybenzoic Acid by Exchange with 4-Toluenesulfonic Acid 270
31.4.1.3.1.2.2 Method 2: [Bis(acyloxy)iodo]arenes from Other [Bis(acyloxy)iodo]arenes by Exchange with Carboxylic Acids 271
31.4.1.3.1.2.3 Method 3: Phenyliodine(III) Sulfate from (Diacetoxyiodo)benzene 272
31.4.1.3.1.2.4 Method 4: Iodosylarenes by Hydrolysis of [Bis(acyloxy)iodo]arenes 272
31.4.1.3.1.2.5 Method 5: Aryliodine(III) Amides from (Acyloxyiodo)arenes 273
31.4.1.3.1.2.6 Method 6: Alkynyl(aryl)iodonium Salts from Hypervalent Iodoarenes 274
31.4.1.3.1.2.6.1 Variation 1: Alkynyl(aryl)iodonium Tetrafluoroborates 274
31.4.1.3.1.2.6.2 Variation 2: Alkynyl(aryl)iodonium Trifluoroacetates 275
31.4.1.3.1.2.6.3 Variation 3: Alkynyl(aryl)iodonium Organosulfonates 276
31.4.1.3.1.2.6.4 Variation 4: 1-Alkynylbenziodoxoles 277
31.4.1.3.1.2.7 Method 7: Aryl- and Hetaryliodonium Salts from Hypervalent Iodoarenes 278
31.4.1.3.1.2.7.1 Variation 1: Aryliodonium Tetrafluoroborates 278
31.4.1.3.1.2.7.2 Variation 2: Aryl- and Hetaryliodonium Sulfonates 279
31.4.1.3.1.2.7.3 Variation 3: Aryliodonium Halides 281
31.4.1.3.1.2.7.4 Variation 4: 1-Arylbenziodoxoles 283
31.4.1.3.1.2.8 Method 8: 1-(Trifluoromethyl)benziodoxoles by Trifluoromethylation of Other Benziodoxoles 284
31.4.1.3.1.2.9 Method 9: Aryliodonium Ylides from (Diacetoxyiodo)arenes 285
31.4.1.3.1.2.10 Method 10: Aryliodonium Imides from (Diacetoxyiodo)arenes 286
31.4.1.3.2 Applications of Hypervalent Iodoarenes and Aryliodonium Salts in Organic Synthesis 287
31.4.1.3.2.1 Preparation of Products with a New C-C Bond 288
31.4.1.3.2.1.1 Method 1: Alkynylation Using 1-Alkynylbenziodoxoles 288
31.4.1.3.2.1.2 Method 2: Arylation Using Diaryliodonium Salts 289
31.4.1.3.2.1.3 Method 3: Trifluoromethylation Using (Trifluoromethyl)benziodoxoles 290
31.4.1.3.2.1.4 Method 4: Reactions of Aryliodonium Ylides 291
31.4.1.3.2.2 Preparation of Products with a New C-F Bond 293
31.4.1.3.2.2.1 Method 1: a-Fluorination of Carbonyl Compounds 293
31.4.1.3.2.2.2 Method 2: Fluorination of Aromatic Compounds 294
31.4.1.3.2.3 Preparation of Products with a New C-Cl Bond 294
31.4.1.3.2.3.1 Method 1: Chlorination of Unsaturated Compounds 294
31.4.1.3.2.4 Preparation of Products with a New C-I Bond 295
31.4.1.3.2.4.1 Method 1: Oxidative Iodination Using Hypervalent Iodoarenes 295
31.4.1.3.2.5 Oxidations and Oxidative Rearrangements 296
31.4.1.3.2.5.1 Reactions with Iodine(V) Reagents 296
31.4.1.3.2.5.1.1 Method 1: Oxidations with Iodylarenes 296
31.4.1.3.2.5.1.2 Method 2: Iodine(V)-Catalyzed Oxidations 297
31.4.1.3.2.5.1.2.1 Variation 1: Catalytic Oxidation of Alcohols to Carbonyl Compounds 297
31.4.1.3.2.5.1.2.2 Variation 2: Catalytic Oxidation at the Benzylic Position 298
31.4.1.3.2.5.1.2.3 Variation 3: Catalytic Preparation of a,b-Unsaturated Carbonyl Compounds 298
31.4.1.3.2.5.2 Reactions with Iodine(III) Reagents 299
31.4.1.3.2.5.2.1 Method 1: 2,2,6,6-Tetramethylpiperidin-1-oxyl-Catalyzed Oxidation of Alcohols 299
31.4.1.3.2.5.2.2 Method 2: Diacetoxylation of Alkenes 300
31.4.1.3.2.5.2.3 Method 3: Oxidative Dearomatization of Phenols and Phenol Ethers 301
31.4.1.3.2.5.2.3.1 Variation 1: Oxidation of 4-Substituted Phenols 301
31.4.1.3.2.5.2.3.2 Variation 2: Oxidation of 2-Substituted Phenols 303
31.4.1.3.2.5.2.4 Method 4: Iodine(III)-Catalyzed Oxidations 304
31.4.1.3.2.5.2.4.1 Variation 1: Catalytic a-Functionalization of Carbonyl Compounds 304
31.4.1.3.2.5.2.4.2 Variation 2: Catalytic Lactonization Reactions 305
31.4.1.3.2.5.2.4.3 Variation 3: Catalytic Stereoselective Diacetoxylation of Alkenes 305
31.4.1.3.2.5.2.4.4 Variation 4: Catalytic Oxidative Cleavage of Alkenes and Alkynes 306
31.4.1.3.2.5.2.4.5 Variation 5: Catalytic Spirocyclization of Aromatic Substrates 306
31.4.1.3.2.6 Preparation of Products with a New C-N Bond 308
31.4.1.3.2.6.1 Method 1: Azidations with Iodine(III) Reagents 308
31.4.1.3.2.6.2 Method 2: Aminations with Iodine(III) Reagents 308
31.4.1.3.2.6.3 Method 3: Reactions of Aryliodonium Imides 310
31.4.1.3.2.6.3.1 Variation 1: C-H Amidation 310
31.4.1.3.2.6.3.2 Variation 2: Aziridination of Alkenes 311
31.4.1.3.2.7 Oxidations at Nitrogen 311
31.4.1.3.2.7.1 Method 1: Hypervalent Iodoarenes as Reagents for Hofmann Rearrangement 311
31.4.1.3.2.7.1.1 Variation 1: Hypervalent Iodine Catalyzed Hofmann Rearrangement 312
31.4.1.3.2.7.2 Method 2: Hypervalent Iodoarenes as Reagents for Generation of Nitrile Oxides from Oximes 313
31.4.1.3.2.7.2.1 Variation 1: Synthesis of Dihydroisoxazoles via Hypervalent Iodine Catalyzed Generation of Nitrile Oxides 314
31.41.3 Arylphosphine Oxides and Heteroatom Derivatives (Update 2015) 319
31.41.3.1 Arylphosphine Oxides 319
31.41.3.1.1 Synthesis of Arylphosphine Oxides 319
31.41.3.1.1.1 Method 1: Oxidation of Phosphines and Derivatives 319
31.41.3.1.1.1.1 Variation 1: Oxidation with Dioxygen or Air 320
31.41.3.1.1.1.2 Variation 2: Catalytic Oxidation 320
31.41.3.1.1.1.3 Variation 3: Oxidation with Peroxides 323
31.41.3.1.1.1.4 Variation 4: Photooxidation 325
31.41.3.1.1.1.5 Variation 5: Oxidation with Miscellaneous Oxidants 325
31.41.3.1.1.1.6 Variation 6: Oxidation of Chalcogen Phosphine Derivatives and Phosphine–Boranes 328
31.41.3.1.1.2 Method 2: Addition of Secondary Phosphine Oxides to Unsaturated Bonds 329
31.41.3.1.1.2.1 Variation 1: Addition to Unsaturated Carbon-Carbon Bonds 329
31.41.3.1.1.2.2 Variation 2: Addition to Imines 331
31.41.3.1.1.2.3 Variation 3: Addition to Carbonyl Compounds 334
31.41.3.1.1.2.4 Variation 4: Conjugate Addition to Activated Alkenes 337
31.41.3.1.1.3 Method 3: Nucleophilic Substitution at the Phosphorus Atom 341
31.41.3.1.1.3.1 Variation 1: P-X Bond Cleavage (X = Halogen) 341
31.41.3.1.1.3.2 Variation 2: P-O Bond Cleavage 347
31.41.3.1.1.3.3 Variation 3: P-C Bond Cleavage 349
31.41.3.1.1.3.4 Variation 4: Hydrolysis of Phosphonium Salts 351
31.41.3.1.1.3.5 Variation 5: Electrophilic Aromatic Substitution 355
31.41.3.1.1.4 Method 4: Nucleophilic Substitutionwith Phosphorus Nucleophiles 355
31.41.3.1.1.4.1 Variation 1: Michaelis–Becker Reactions 355
31.41.3.1.1.4.2 Variation 2: Michaelis–Arbuzov Reactions 357
31.41.3.1.1.5 Method 5: Transition-Metal-Mediated P-C Bond Formation 360
31.41.3.1.1.5.1 Variation 1: Copper-Mediated Reactions 361
31.41.3.1.1.5.2 Variation 2: Nickel-Mediated Reactions 363
31.41.3.1.1.5.3 Variation 3: Palladium-Mediated Reactions 366
31.41.3.1.1.5.4 Variation 4: Other Metal-Mediated Reactions 371
31.41.3.1.1.6 Method 6: Other Reactions 373
31.41.3.1.1.6.1 Variation 1: Phosphinylation of Ortho Esters 373
31.41.3.1.1.6.2 Variation 2: Manganese(III)-Mediated Free-Radical Phosphinylation 374
31.41.3.1.1.6.3 Variation 3: Palladium-Catalyzed Intramolecular Dehydrogenative Cyclization 375
31.41.3.1.1.6.4 Variation 4: Reaction of Elemental Phosphorus 376
31.41.3.1.1.6.5 Variation 5: The Wittig Reaction 376
31.41.3.1.1.6.6 Variation 6: The Appel Reaction 377
31.41.3.1.1.6.7 Variation 7: The Mitsunobu Reaction 378
31.41.3.1.1.7 Method 7: Modification of Phosphine Oxides without Substitution at Phosphorus 379
31.41.3.1.1.7.1 Variation 1: Monoreduction of Bisphosphine Dioxides 379
31.41.3.1.1.7.2 Variation 2: Deprotonation Directed by the P=O Group 380
31.41.3.1.1.7.3 Variation 3: Nucleophilic Aromatic Substitution Promoted by the P=O Group 382
31.41.3.1.1.7.4 Variation 4: Alkene Metathesis 384
31.41.3.1.1.7.5 Variation 5: Cycloaddition Reactions 385
31.41.3.1.1.7.6 Variation 6: Annulation Reactions 388
31.41.3.1.1.7.7 Variation 7: Cross-Coupling Reactions 389
31.41.3.1.2 Applications of Arylphosphine Oxides in Organic Synthesis 392
31.41.3.2 Arylphosphine Sulfides 392
31.41.3.2.1 Synthesis of Arylphosphine Sulfides 392
31.41.3.2.1.1 Method 1: Sulfuration of Phosphines 392
31.41.3.2.1.1.1 Variation 1: Using Elemental Sulfur 392
31.41.3.2.1.1.2 Variation 2: Using Polysulfide Reagents 393
31.41.3.2.1.1.3 Variation 3: Using Other Sulfur Sources 396
31.41.3.2.1.1.4 Variation 4: Via Sulfuration of Phosphine–Borane Species 397
31.41.3.2.1.1.5 Variation 5: Via Sulfuration of Other Chalcogen Phosphine Derivatives 397
31.41.3.2.1.2 Method 2: Addition of Secondary Phosphine Sulfides to Unsaturated Bonds 399
31.41.3.2.1.2.1 Variation 1: Addition to Carbonyl Compounds 399
31.41.3.2.1.2.2 Variation 2: Addition to Alkenes 400
31.41.3.2.1.2.3 Variation 3: Conjugate Addition to Activated Alkenes 402
31.41.3.2.1.3 Method 3: Nucleophilic Substitutionwith Phosphorus 403
31.41.3.2.1.3.1 Variation 1: Transition-Metal-Mediated Substitution 404
31.41.3.2.1.3.2 Variation 2: Thio-Michaelis–Arbuzov Reactions 405
31.41.3.2.1.4 Method 4: Nucleophilic Substitution at the Phosphorus Atom 406
31.41.3.2.1.4.1 Variation 1: P-X Bond Cleavage (X = Halogen) 407
31.41.3.2.1.4.2 Variation 2: P-S Bond Cleavage 408
31.41.3.2.1.4.3 Variation 3: P-C Bond Cleavage 409
31.41.3.2.1.4.4 Variation 4: P-O Bond Cleavage 410
31.41.3.2.1.4.5 Variation 5: Solvolysis of Phosphorus(V) Compounds 410
31.41.3.2.1.5 Method 5: Other Reactions 411
31.41.3.2.1.5.1 Variation 1: Reaction of Sulfides with Elemental Phosphorus 411
31.41.3.2.1.5.2 Variation 2: Cycloaddition of Strained Cyclic Phosphine Sulfides with Dienes 411
31.41.3.2.1.5.3 Variation 3: Wittig Reaction with Thiocarbonyl Compounds 412
31.41.3.2.1.5.4 Variation 4: Reaction of Ylides with Elemental Sulfur and with Thiiranes 412
31.41.3.2.1.5.5 Variation 5: Cycloaddition of (Alkylsulfanyl)(chloro)phosphines 413
31.41.3.2.1.5.6 Variation 6: Reaction of Butadienylphosphine Sulfides 414
31.41.3.2.1.6 Method 6: Modification of Phosphine Sulfides without Substitution at Phosphorus 414
31.41.3.2.1.6.1 Variation 1: a- and ortho-Deprotonation 415
31.41.3.2.1.6.2 Variation 2: Cycloaddition Reactions 415
31.41.3.2.1.6.3 Variation 3: Annulation Reactions 418
31.41.3.2.2 Applications of Arylphosphine Sulfides in Organic Synthesis 418
31.41.3.3 Arylphosphine Selenides 418
31.41.3.3.1 Synthesis of Arylphosphine Selenides 419
31.41.3.3.1.1 Method 1: Selenation of Free Phosphines with Elemental Selenium 419
31.41.3.3.1.2 Method 2: Other Methods 420
31.41.3.3.2 Applications of Arylphosphine Selenides in Organic Synthesis 421
31.41.3.4 Aryl(imino)phosphoranes 421
31.41.3.4.1 Synthesis of Aryl(imino)phosphoranes 421
31.41.3.4.1.1 Method 1: The Staudinger Reaction of Free Phosphines and Azides 421
31.41.3.4.1.2 Method 2: Synthesis via Aminophosphonium Salts 423
31.41.3.4.2 Applications of Aryl(imino)phosphoranes in Organic Synthesis 424
35.2.5.1.9 Synthesis by Addition across C=C Bonds (Update 2015) 441
35.2.5.1.9.1 Method 1: Hydroxy- and Alkoxybromination of Alkenes 441
35.2.5.1.9.2 Method 2: Aminobromination of Alkenes 450
35.2.5.1.9.3 Method 3: Azidobromination of Alkenes 456
35.2.5.1.9.4 Method 4: Phosphobromination of Alkenes 457
35.2.5.1.9.5 Method 5: Catalytic Enantioselective Syntheses 458
35.2.5.1.9.5.1 Variation 1: Bromination of Alkenes 459
35.2.5.1.9.5.2 Variation 2: Hydroxy- and Alkoxybromination of Alkenes 460
35.2.5.1.9.5.3 Variation 3: Aminobromination of Alkenes 478
Author Index 491
Abbreviations 523

Textauszug

4.4.4.8 Silyl Hydrides (Update 2015)

R. W. Clark and S. L. Wiskur

General Introduction

The product subclass discussed herein is previously discussed in Houben–Weyl, Vol. 13/5, pp 79–96; silyl hydrides and their application as reducing agents is included in Houben–Weyl, Vol. 13/5, pp 350–360. More detailed examples include asymmetric reductions (Houben–Weyl, Vol. E 21, pp 4067–4081), transition-metal-catalyzed hydrosilylations (Houben–Weyl, Vol. E 18, pp 685–742), and stereoselective hydrosilylations of alkenes and dienes (Houben–Weyl, Vol. E 21, pp 5733–5740). This section is limited in scope to silicon-based compounds containing at least one Si-H bond. Specifically, the subsequent section highlights recent scientific discoveries regarding the subclass since last reviewed in Science of Synthesis in 2001 (Section 4.4.4). The text that follows is not all inclusive, but rather seeks to highlight the most synthetically viable preparation methods for this class of compounds, including the preparation of chlorinated silyl hydrides and silyl hydrides that are stereogenic at silicon. The use of these silyl hydrides will also be explored. The application of silyl hydrides as reagents in other important synthetic processes is of particular interest; therefore, this update has a large focus on this. Progress in the field of hydrosilylation, reduction, and dehydrogenative silylation of carbonyl compounds, alkenes, alkynes, and other functional groups is discussed in the following sections.

SAFETY: Silane (SiH4) is an extremely pyrophoric gas which should be avoided where possible.[1] This reactive gas is also known to form via disproportionation from less reactive silyl precursors during the course of a reaction. An example of such a precursor is triethoxysilane; it is known to produce silane under an inert atmosphere when in the presence of a metal catalyst.[2] Large-scale reactions or an excess of silane in such reactions are known to create uncontrollable exothermic reactions leading to fires and explosions.[3] Great care should be exercised when silane or its precursors are handled. Cases that are discussed in subsequent sections where silane is possibly formed as a byproduct are clearly labeled as such.

Organosilanes (R1SiH3, R12SiH2, and R13SiH) are generally much less reactive than silane. These compounds become more stable to hydrolysis, oxidation, and other reactions as alkyl or aryl substitution at silicon increases. Alkyl- or arylsilanes possess many physical properties similar to alkanes: most are highly flammable liquids or gases with high thermal stabilities.[4] Notable differences to alkanes should be noted. Silanes, especially when monoalkylated, are sensitive to hydrolysis and should be stored under an inert atmosphere. These compounds should also be stored away from acids, bases, and fluorides as these conditions produce unwanted and flammable dihydrogen.[5]

As with most reagents, silanes should be handled with care to avoid inhalation, skin contact, and ingestion. Always use a fume hood when handling these volatile compounds. Because of the vast differences in reactivity of these compounds, a thorough knowledge of the particular silane to be utilized or synthesized is necessary.

4.4.4.8.1 Synthesis of Silyl Hydrides

4.4.4.8.1.1 Method 1: From Inorganic Silanes

Dialkyl- and diarylsilanes continue to be prepared from dichlorosilane and alkyl- or aryllithium or Grignard reagents.[6] However, the gaseous and explosive dichlorosilane can be made a more feasible reagent when used as an N,N,N′,N′-tetraethylethylenediamine complex [(teeda)•H2SiCl2], which is prepared from N,N,N′,N′-tetraethylethylenediamine (teeda) and trichlorosilane.[7,8] This complex is a solid and is stable upon storage away from moisture and air.[9] Various silanes are prepared from this complex including secondary silanes and silacycles. As an example of a secondary silane, diphenylsilane can be synthesized in 75% yield by reacting [(teeda)•H2SiCl2] with phenylmagnesium chloride in a 1:3 dichloromethane/tetrahydrofuran solution at room temperature.[7] When the reaction is attempted in tetrahydrofuran or diethyl ether, the secondary silanes are still obtained, but in moderate yields due to the formation of biphenyl as a major impurity.[9] Presumably, this decrease in reactivity is due to insolubility of the silyl chloride complex in tetrahydrofuran and diethyl ether. Reaction of diorganometallic biaryls with the [(teeda)•H2SiCl2] complex at room temperature in a mixture of dichloromethane and tetrahydrofuran yields silacyclopentadienes (siloles, e.g., 1) in good yield (▶ Scheme 1). Siloles (five-membered rings containing silicon and a butadiene) such as 1 or 3 are of synthetic importance due to their direct applicability as monomers for functional materials[10] such as organic light-emitting diodes[11] and field-effect transistors.[12]

Scheme 1 Reaction of a Diorganometallic Biaryl with the N,N,N′,N′-Tetraethylethylenediamine Complex of Dichlorosilane[9]

Siloles can also be prepared in high-yielding reactions from zirconacyclopentadienes 2, but these reactions require the use of dichlorosilane as a silane source (▶ Scheme 2).[13] The reaction proceeds rapidly at room temperature in chloroform to produce siloles 3 in excellent yield. More sterically demanding dienes require longer reaction times to produce similar yields. Extending the reaction to include other inorganic silanes is not as successful. For example, no reaction occurs with tetrachlorosilane, and trichlorosilane yields a ternary mixture of siloles.

Scheme 2 Preparation of Siloles from Zirconacyclopentadienes[13]

R1	R2	Time	Yield (%)	Ref

Et

Et

5 min

92

[13]

TMS

Me

24 h

97

[13]

Tertiary triaryl- and trialkylsilanes, like secondary silanes, are historically prepared from trichlorosilane[14,15] and aryl or alkyl Grignard reagents.[16] The synthesis of triallylsilane is also amenable to this method. In cases where dilithiation of the aryl group is possible, the synthesis of triarylsilanes can be improved by isolation of the aryllithium salt after lithium–halogen exchange with butyllithium at room temperature in pentane (▶ Scheme 3).[17] The salt is purified by centrifugation and repeated washes with cold pentane. The purified salt is then reacted directly with trichlorosilane in pentane at room temperature to form the triarylsilanes (e.g., 4) in excellent yields. Note: Care must be taken when isolating the pyrophoric aryllithium salts.

Scheme 3 Improved Preparation of a Triarylsilane from Trichlorosilane[17]

3,7-Di-tert-butyl-5H-dibenzo[b,d]silole (1); Typical Procedure:[9]

CAUTION:

1,2-Dibromoethane is an eye, skin, and respiratory tract irritant and is aprobable human carcinogen.

A soln of 2,2′-dibromo-4,4′-di-tert-butylbiphenyl (2.01 g, 4.71 mmol) in THF (30 mL) containing 1,2-dibromoethane (0.4 mL) was added slowly to a suspension of Mg (0.567 g, 23.3 mmol) in THF (5 mL). The reaction was slightly exothermic and the addition took approximately 0.5 h. The mixture was then heated to reflux for 2 h, and cooled to rt. A slurry of [(teeda)•H2SiCl2] (1.3 g, 4.72 mmol) in CH2Cl2 (8 mL) was prepared and cannulated into the Grignard soln, resulting in the formation of a clear soln. The mixture was stirred overnight, followed by solvent removal and the addition of Et2O (30 mL) and 0.2 M aq HCl (50 mL). The organic layer was separated and dried (MgSO4), and the solvent was removed. Kugelrohr distillation of the crude product resulted in the desired product in the first fraction (bp 150–190 °C/0.2 Torr). That fraction was dissolved in abs EtOH and cooled to −7 °C to yield the product as a white solid; yield: 0.269 g (19%).

Tris(4-bromophenyl)silane (4); Typical Procedure:[17]

To a stirred soln of 1-bromo-4-iodobenzene (6.5 g, 23 mmol) in pentane (65 mL) at rt, a 1.6 M soln of BuLi in hexanes (14.4 mL, 23 mmol) was added dropwise and allowed to react for 1 h, producing a precipitate. The soln was centrifuged for 5 min at 2400 rpm and the supernatant was removed via syringe. Pentane (70 mL) was added to the sediment and the suspension was stirred for 5 min. The suspension was centrifuged again and the supernatant was again removed via syringe. A soln of HSiCl3 (0.95 g, 7.0 mmol) in pentane (17.5 mL) was added to the soln of (4-bromophenyl)lithium in pentane (50 mL) at rt (CAUTION: exothermic reaction). The reaction was stirred at rt for 2 h. The suspension was then centrifuged and the supernatant removed via syringe. The solids were again stirred with pentane (70 mL) and centrifuged. The supernatants were combined and quenched with TMSCl (0.5 mL) and...

Produkt-Details

• Erscheint lt. Verlag: 13.5.2015
• Reihe/Serie: Science of Synthesis
• Verlagsort: Stuttgart
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Chemie ► Organische Chemie
• Themenwelt: Technik
• Schlagworte: Acetanilides • Alkynylsilanes • Anisoles • Arylalkanes • Aryliodonium Salts • Arylphosphine Oxides • Benzonitriles • Boron • Bromine • Bromoarenes • Carbometalation • C=C Bonds • Cesium Fluoride • Chemie • Chemische Synthese • chemistry of organic compound • chemistry organic reaction • chemistry reference work • chemistry synthetic methods • Chloroarenes • compound functional group • compound organic synthesis • Fluoroarenes • Heteroatom Derivatives • Hydrometalation • Hydrosilylation • Hypervalent Iodoarenes • Iridium Catalysis • Mechanism • Method • methods in organic synthesis • methods peptide synthesis • nitrogen • Organic Chemistry • organic chemistry functional groups • organic chemistry reactions • organic chemistry review • organic chemistry synthesis • organic method • organic reaction • organic reaction mechanism • Organic Syntheses • organic synthesis • organic synthesis reference work • Organisch-chemische Synthese • Organische Chemie • oxygen • Peptide synthesis • PhenoFluor • Phenols • Practical • practical organic chemistry • Reaction • reference work • Review • review organic synthesis • review synthetic methods • Semihydrogenation • Silylcupration • Silyl Hydrides • Silylmetalation • Silylrhodation • Silylzincation • Synthese • Synthetic chemistry • Synthetic Methods • Synthetic Organic Chemistry • synthetic transformation • Trifluoromethanesulfonate • Vinylsilanes
• ISBN-10: 3-13-176381-7 / 3131763817
• ISBN-13: 978-3-13-176381-5 / 9783131763815