Science of Synthesis: Houben-Weyl Methods of Molecular Transformations Vol. 43 (eBook)

Science of Synthesis – Volume 43: Polyynes, Arynes, Enynes, and Alkynes 1
Title page 3
Imprint 5
Preface 6
Volume Editor's Preface 8
Overview 10
Table of Contents 12
Introduction 30
43.1 Product Class 1: Linear Conjugated Diynes, Oligoynes, and Polyynes 66
43.1.1 Product Subclass 1: Alka-1,3-diynes 67
43.1.1.1 Synthesis of Product Subclass 1 67
43.1.1.1.1 Method 1: Copper-Promoted Oxidative Homocoupling of Terminal Alkynes 67
43.1.1.1.1.1 Variation 1: Glaser Coupling 68
43.1.1.1.1.2 Variation 2: Eglinton Coupling 71
43.1.1.1.1.3 Variation 3: Hay Coupling 73
43.1.1.1.1.4 Variation 4: Copper-Promoted Oxidative Homocoupling of Silylacetylenes 77
43.1.1.1.1.5 Variation 5: Copper-Mediated Solid-State Coupling 78
43.1.1.1.1.6 Variation 6: Silver(I) 4-Toluenesulfonate/Copper(II) Chloride/N,N,N',N'-Tetramethylethylenediamine Catalytic System and Solid-Phase On-Bead Coupling 78
43.1.1.1.2 Method 2: Heterocoupling of Terminal Alkynes with 1-Haloalkynes 80
43.1.1.1.2.1 Variation 1: The Cadiot--Chodkiewicz Coupling 80
43.1.1.1.2.2 Variation 2: Polymer-Supported Cadiot--Chodkiewicz Coupling 83
43.1.1.1.2.3 Variation 3: Other Copper(I)-Catalyzed Heterocoupling Reactions 84
43.1.1.1.2.4 Variation 4: Cross Coupling of Alkynyl(phenyl)iodonium 4-Toluenesulfonates 85
43.1.1.1.2.5 Variation 5: Copper(I)-Promoted Heterocoupling between Silylalkynes and Chloroalkynes 86
43.1.1.1.3 Method 3: Homocoupling of Alkynyl Grignard Compounds 86
43.1.1.1.4 Method 4: Heterocoupling of Alkynyl Grignard Derivatives with 1-Haloalkynes 87
43.1.1.1.5 Method 5: Homocoupling of Alkynyllithium Compounds 88
43.1.1.1.6 Method 6: Coupling of Alkynylstannanes 89
43.1.1.1.6.1 Variation 1: Homocoupling of Alkynylstannanes 89
43.1.1.1.6.2 Variation 2: Cross Coupling of Alkynylstannanes 89
43.1.1.1.7 Method 7: Homocoupling and Cross Coupling of Alkynylboron Derivatives 90
43.1.1.1.8 Method 8: Dimerization of 1-Selanylalkynes 91
43.1.1.1.9 Method 9: Demercuration of Bis(alkynyl)mercury Compounds 92
43.1.1.1.10 Method 10: Coupling of Alkynylnickel Complexes 92
43.1.1.1.11 Method 11: Buta-1,3-diynes from Alkynylzirconocenes 93
43.1.1.1.12 Method 12: Palladium-Catalyzed Coupling of Terminal Alkynes 93
43.1.1.1.12.1 Variation 1: Homocoupling of Terminal Alkynes 94
43.1.1.1.12.2 Variation 2: Heterocoupling of Terminal Alkynes 96
43.1.1.1.13 Method 13: Palladium-Catalyzed Coupling of Alkynylstannanes 99
43.1.1.1.14 Method 14: Other Transition-Metal-Mediated Alkyne Coupling Processes 99
43.1.1.1.15 Method 15: Elimination of a Hydrogen Halide from 1,4-Dihalobut-2-ynes 100
43.1.1.1.16 Method 16: Elimination of a Hydrogen Halide from Haloalkenynes 101
43.1.1.1.16.1 Variation 1: Elimination of a Hydrogen Halide from 1-Haloalk-1-en-3-ynes 101
43.1.1.1.16.2 Variation 2: Elimination of a Hydrogen Halide from 2-Haloalk-1-en-3-ynes 104
43.1.1.1.16.3 Variation 3: Elimination of a Hydrogen Halide from 1-Haloalk-3-en-1-ynes 105
43.1.1.1.17 Method 17: Buta-1,3-diyne Formation from Carbenes and Carbenoids (Fritsch--Buttenberg--Wiechell Rearrangement) 106
43.1.1.1.18 Method 18: Synthesis of Buta-1,3-diynes via Phosphorus Ylides 108
43.1.1.1.18.1 Variation 1: Wittig Synthesis Using Phosphacumulene Ylides 108
43.1.1.1.18.2 Variation 2: Flash-Vacuum Pyrolysis of 2-Oxoalk-3-ynylidenetriphenylphosphoranes 109
43.1.1.1.19 Method 19: Base-Catalyzed Triple-Bond Isomerizations (Zipper Reaction) 111
43.1.2 Product Subclass 2: Linear Conjugated Oligoynes and Polyynes 112
43.1.2.1 Synthesis of Product Subclass 2 112
43.1.2.1.1 Method 1: Convergent Synthesis of Polyynes by Acetylene Coupling Reactions 112
43.1.2.1.1.1 Variation 1: Glaser Coupling 112
43.1.2.1.1.2 Variation 2: Eglinton Coupling 113
43.1.2.1.1.3 Variation 3: Hay Coupling 115
43.1.2.1.2 Method 2: Cadiot--Chodkiewicz Cross Coupling 120
43.1.2.1.3 Method 3: Tetraynes from Oxidative Homocoupling of Alkadiynyl Grignard Derivatives 123
43.1.2.1.4 Method 4: Homocoupling of Transition-Metal-Bound Buta-1,3-diynes 124
43.1.2.1.5 Method 5: Iterative Synthesis of Polyynes Using Acetylene Coupling Reactions 124
43.1.2.1.6 Method 6: Dehydrohalogenation of Halogenated Polyynic Precursors 127
43.1.2.1.6.1 Variation 1: Elimination of Hydrogen Chloride from 1,6-Dichlorohexa-2,4-diynes 127
43.1.2.1.6.2 Variation 2: Convergent Synthesis of Polyynes by the Alkynylation/Elimination of 1,1-Dibromoalk-1-en-3-ynes 128
43.1.2.1.7 Method 7: Polyyne Formation from Carbenes and Carbenoids (Fritsch--Buttenberg--Wiechell Rearrangement) 129
43.1.2.1.8 Method 8: Synthesis of Higher Polyynes by Pyrolysis 133
43.1.2.1.8.1 Variation 1: Flash-Vacuum Pyrolysis of Ethyl 3-Oxo-7-(4-tolyl)-2-(triphenylphosphoranylidene)hepta-4,6-diynoate 133
43.1.2.1.8.2 Variation 2: Linear Polyynes from Solution-Spray Flash-Vacuum Pyrolysis of Cyclobutene-1,2-diones 134
43.1.3 Product Subclass 3: Polydisperse Polyyne Fractions with Varying Numbers of Triple Bonds 134
43.1.3.1 Synthesis of Product Subclass 3 134
43.1.3.1.1 Method 1: Laser Ablation of Carbon Particles in Suspension 134
43.1.3.1.2 Method 2: Synthesis by Electric Arc Discharge 135
43.1.3.1.3 Method 3: Synthesis of Polydisperse Polyyne Solutions from the Hydrolysis of Carbides 136
43.1.3.1.4 Method 4: Polydisperse a,.-Dicyanopolyyne Fractions from Electric Arcing 137
43.2 Product Class 2: Cyclic Conjugated Diynes, Triynes, Tetraynes, and Polyynes 148
43.2.1 Product Subclass 1: Cyclic Conjugated Diynes 148
43.2.1.1 Synthesis of Product Subclass 1 148
43.2.1.1.1 Oxidative Homocoupling 148
43.2.1.1.1.1 Method 1: Glaser--Eglinton Conditions with Terminal Alkynes 149
43.2.1.1.1.1.1 Variation 1: Synthesis via Oligomerization under Standard Conditions 149
43.2.1.1.1.1.2 Variation 2: Synthesis via Oligomerization with Addition of Copper(I) Chloride 151
43.2.1.1.1.1.3 Variation 3: Synthesis via Oligomerization under Oxygen-Free Conditions 152
43.2.1.1.1.1.4 Variation 4: Synthesis via Oligomerization in Acetonitrile 152
43.2.1.1.1.1.5 Variation 5: Stepwise Synthesis under Standard Conditions 153
43.2.1.1.1.1.6 Variation 6: Stepwise Synthesis with Addition of Copper(I) Chloride 154
43.2.1.1.1.1.7 Variation 7: Stepwise Synthesis under Oxygen-Free Conditions 155
43.2.1.1.1.2 Method 2: Hay Conditions with Terminal Alkynes 156
43.2.1.1.1.2.1 Variation 1: Synthesis via Oligomerization 156
43.2.1.1.1.2.2 Variation 2: Stepwise Synthesis 158
43.2.1.1.2 Oxidative Heterocoupling of Terminal Alkynes and Bromoalkynes 159
43.2.1.1.2.1 Method 1: Cadiot--Chodkiewicz Conditions 159
43.2.1.1.2.1.1 Variation 1: With Pyridine as Solvent 159
43.2.1.1.2.1.2 Variation 2: Under Palladium Catalysis 161
43.2.1.1.3 Nucleophilic Substitution 162
43.2.1.1.3.1 Method 1: Reaction of Sodium Acetylides with Alkyl Bromides 162
43.2.1.1.3.1.1 Variation 1: Synthesis of Symmetrical Diynes 162
43.2.1.1.3.1.2 Variation 2: Synthesis of Unsymmetrical Diynes 163
43.2.1.1.4 Cumulene Dimerization 164
43.2.1.1.4.1 Method 1: Dimerization under Copper Catalysis 164
43.2.1.1.4.2 Method 2: Dimerization without Copper Catalysis 164
43.2.1.1.4.3 Method 3: 1,6-Elimination from 1,6-Dibromohexa-2,4-diyne Followed by Dimerization 165
43.2.1.1.5 Iodolactonization 165
43.2.1.2 Applications of Product Subclass 1 in Organic Synthesis 166
43.2.1.2.1 Method 1: Reaction with Sulfur 166
43.2.1.2.2 Method 2: Reaction with Tetrachlorothiophene 1,1-Dioxide 166
43.2.1.2.3 Method 3: Palladium-Catalyzed Enyne--Diyne Cross-Benzannulation 167
43.2.1.2.4 Method 4: Hydrogenation 167
43.2.1.2.5 Method 5: Reduction with a Trialkylborane 168
43.2.1.2.6 Method 6: Annulene Formation 168
43.2.1.2.7 Method 7: Radialene Formation 168
43.2.1.2.8 Method 8: Transannular Cyclization 169
43.2.1.2.8.1 Variation 1: With Potassium Hydroxide 169
43.2.1.2.8.2 Variation 2: With Potassium Hydroxide and Heat 169
43.2.1.2.8.3 Variation 3: With Sodium Bis(2-methoxyethoxy)aluminum Hydride 170
43.2.2 Product Subclass 2: Cyclic Conjugated Triynes 170
43.2.2.1 Synthesis of Product Subclass 2 170
43.2.2.1.1 Nucleophilic Substitution 170
43.2.2.1.1.1 Method 1: Reaction of Sodium Acetylides with Alkyl Bromides 171
43.2.3 Product Subclass 3: Cyclic Conjugated Tetraynes 171
43.2.3.1 Synthesis of Product Subclass 3 171
43.2.3.1.1 Oxidative Homocoupling 171
43.2.3.1.1.1 Method 1: Glaser--Eglinton Conditions 171
43.2.3.1.2 Carbenoid Rearrangement 172
43.2.3.1.2.1 Method 1: Fritsch--Buttenberg--Wiechell Conditions 172
43.2.4 Product Subclass 4: Cyclic Conjugated Polyynes 173
43.2.4.1 Synthesis of Product Subclass 4 173
43.2.4.1.1 Method 1: Decarbonylation 173
43.2.4.1.2 Method 2: Retro-Diels--Alder Reactions 174
43.2.4.1.3 Method 3: Retro-[2 + 2] Reactions 174
43.2.4.1.4 Method 4: [2 + 1]-Cheletropic Fragmentation 175
43.2.4.2 Applications of Product Subclass 4 in Organic Synthesis 175
43.2.4.2.1 Method 1: Reaction with Furan 175
43.2.4.2.2 Method 2: Fullerene Formation 176
43.3 Product Class 3: Arynes 180
43.3.1 Product Subclass 1: 1,2-Didehydroarenes and 1,2-Didehydrohetarenes 185
43.3.1.1 Synthesis of Product Subclass 1 185
43.3.1.1.1 Method 1: Elimination of Hydrogen 185
43.3.1.1.2 Method 2: Elimination of a Hydrogen and a Halogen Function 185
43.3.1.1.3 Method 3: Elimination of a Hydrogen and a Nitrogen Function 191
43.3.1.1.4 Method 4: Elimination of a Hydrogen and an Oxygen Function 191
43.3.1.1.5 Method 5: Elimination of a Hydrogen and a Sulfur or Selenium Function 192
43.3.1.1.6 Method 6: Elimination of a Silicon and a Halogen Function 192
43.3.1.1.7 Method 7: Elimination of a Silicon and an Oxygen Function 195
43.3.1.1.8 Method 8: Elimination of Two Carbon Functions 197
43.3.1.1.8.1 Variation 1: From Benzocyclobutene-1,2-diones 197
43.3.1.1.8.2 Variation 2: From Phthalic Anhydrides 199
43.3.1.1.8.3 Variation 3: From Phthaloyl Peroxide 202
43.3.1.1.8.4 Variation 4: From 1H-2,3-Benzoxazin-1-ones 202
43.3.1.1.9 Method 9: Elimination of a Carbon and a Halogen Function 203
43.3.1.1.10 Method 10: Elimination of a Carbon and an Oxygen Function 204
43.3.1.1.11 Method 11: Elimination of a Carbon and a Nitrogen Function 204
43.3.1.1.11.1 Variation 1: From ortho-Diazonioarenecarboxylates 204
43.3.1.1.11.2 Variation 2: From ortho-(3,3-Dimethyltriaz-1-enyl)arenecarboxylic Acids 206
43.3.1.1.12 Method 12: Elimination of Two Halogen Functions 207
43.3.1.1.12.1 Variation 1: From ortho-Haloarylmagnesium Halides 207
43.3.1.1.12.2 Variation 2: From ortho-Haloaryllithium Species 208
43.3.1.1.13 Method 13: Elimination of a Halogen and an Oxygen Function 210
43.3.1.1.13.1 Variation 1: From ortho-(Arylsulfonyloxy)arylmagnesium Chlorides 210
43.3.1.1.13.2 Variation 2: From ortho-Sulfonylaryllithium Compounds 212
43.3.1.1.14 Method 14: Elimination of a Halogen and a Sulfur Function 213
43.3.1.1.15 Method 15: Elimination of a Nitrogen and a Sulfur Function 213
43.3.1.1.16 Method 16: Elimination of Two Nitrogen Functions 214
43.3.1.2 Applications of Product Subclass 1 in Organic Synthesis 216
43.3.1.2.1 Method 1: Diels--Alder Reactions 217
43.3.1.2.2 Method 2: 1,3-Dipolar Cycloaddition Reactions 220
43.3.1.2.3 Method 3: [2 + 2]-Cycloaddition Reactions 223
43.3.1.2.4 Method 4: Ene Reactions 225
43.3.1.2.5 Method 5: Reactions with Nucleophiles 226
43.3.1.2.6 Method 6: Reactions Catalyzed by Palladium 232
43.3.2 Product Subclass 2: 1,3-Didehydroarenes and 1,3-Didehydrohetarenes 235
43.3.2.1 Synthesis of Product Subclass 2 236
43.3.2.1.1 Method 1: Elimination of Two Carbon Functions 236
43.3.2.1.1.1 Variation 1: From Diacetyl Isophthaloyl Peroxide 236
43.3.2.1.1.2 Variation 2: From Cyclophanediones 237
43.3.2.1.2 Method 2: Elimination of Two Halogen Functions 237
43.3.2.1.3 Method 3: Elimination of Two Nitrogen Functions 238
43.3.2.1.4 Method 4: Routes Applicable to Specific meta-Arynes 238
43.3.2.1.4.1 Variation 1: Synthesis of 2-Chloro-1,3-didehydronaphthalene by Elimination of Hydrogen and Halogen Functions 238
43.3.2.1.4.2 Variation 2: Synthesis of 2,4-Didehydrophenol by Elimination of a Carbon and a Nitrogen Function 239
43.3.2.1.4.3 Variation 3: Synthesis of 2-Phenyl-1,3-didehydrobenzene by Rearrangement 239
43.3.2.1.4.4 Variation 4: Synthesis of 1,8-Didehydronaphthalene by Elimination of Two Nitrogen Functions 240
43.3.2.1.4.5 Variation 5: Synthesis of 1,2,3-Tridehydrobenzene by Elimination of One Halogen and Two Carbon Functions 240
43.3.2.1.4.6 Variation 6: Synthesis of Trifluoro-1,3,5-tridehydrobenzene by Elimination of Three Halogen Functions 241
43.3.3 Product Subclass 3: 1,4-Didehydroarenes and 1,4-Didehydrohetarenes 241
43.3.3.1 Synthesis of Product Subclass 3 242
43.3.3.1.1 Method 1: Elimination of Two Carbon Functions 242
43.3.3.1.1.1 Variation 1: From Diacyl Terephthaloyl Peroxides 242
43.3.3.1.1.2 Variation 2: From Propellanes 242
43.3.3.1.2 Method 2: Elimination of Two Halogen Functions 243
43.3.3.1.3 Method 3: Rearrangement Reactions 244
43.4 Product Class 4: Linear Enynes 254
43.4.1 Synthesis of Product Class 4 254
43.4.1.1 Method 1: Palladium-Catalyzed Cross-Coupling Reactions 254
43.4.1.1.1 Variation 1: Using Terminal Alkynes 254
43.4.1.1.2 Variation 2: Using Organoboron Compounds 257
43.4.1.1.3 Variation 3: Using Organomagnesium Compounds 259
43.4.1.1.4 Variation 4: Using Organotin Compounds 261
43.4.1.1.5 Variation 5: Using Organozinc Compounds 263
43.4.1.2 Method 2: Copper-Mediated Reactions 264
43.4.1.2.1 Variation 1: Copper(I) Catalysis with Terminal Alkynes 265
43.4.1.2.2 Variation 2: Starting from Vinylboranes 266
43.4.1.2.3 Variation 3: Starting from Other Vinyl Organometallic Compounds 268
43.4.1.2.4 Variation 4: Starting from Alkynylcopper Species 269
43.4.1.3 Method 3: Carbene Reactions 270
43.4.1.4 Method 4: Elimination Reactions To Form the Alkene 273
43.4.1.4.1 Variation 1: From Propargylic Systems 273
43.4.1.4.2 Variation 2: From Cyclic Carbonates 276
43.4.1.4.3 Variation 3: Coupling--Elimination Reactions 277
43.4.1.4.4 Variation 4: By Carbonyl Alkenation 278
43.4.1.4.5 Variation 5: From Silicon or Sulfur Compounds 281
43.4.1.5 Method 5: Elimination Reactions To Form the Alkyne 283
43.4.1.5.1 Variation 1: From 1,1-Dibromobutadienes 283
43.4.1.5.2 Variation 2: From Vinyl Sulfones 284
43.4.1.6 Method 6: Addition Reactions to Diynes 286
43.4.1.6.1 Variation 1: Addition of Complex Aluminum and Boron Hydrides 286
43.4.1.6.2 Variation 2: Hydrosilylation, Hydrostannylation, and Stannylcupration of Diynes 287
43.4.1.6.3 Variation 3: Hydroaminations, Hydrophosphinylations, and the Addition of Alcohols, Thiols, and Higher Group 16 Analogues 289
43.4.1.6.4 Variation 4: Addition of Carbon Fragments 292
43.4.1.7 Method 7: Synthesis from Heterocyclic Compounds 295
43.4.1.8 Method 8: Synthesis by Rearrangement 297
43.4.1.9 Method 9: Alkyne Dimerizations 302
43.4.1.9.1 Variation 1: Base-Induced Dimerizations 302
43.4.1.9.2 Variation 2: Transition-Metal-Catalyzed Alkyne Dimerizations 303
43.4.1.9.3 Variation 3: Rare Earth and Main Group Metal Catalyzed Dimerizations 308
43.5 Product Class 5: Cyclic Enynes 318
43.5.1 Product Subclass 1: Cyclooctenynes 319
43.5.1.1 Synthesis of Product Subclass 1 319
43.5.1.1.1 Method 1: Alkyne Formation Post Ring Closure 319
43.5.1.1.1.1 Variation 1: Base-Mediated Cycloelimination Reaction 319
43.5.2 Product Subclass 2: Cyclononenynes 320
43.5.2.1 Synthesis of Product Subclass 2 322
43.5.2.1.1 Method 1: Ring Closure by Alkynylmetal Condensations with Carbonyl Groups and Related Electrophiles 322
43.5.2.1.2 Method 2: Ring Closure by Condensation of Alkyne--Hexacarbonyldicobalt Complexes (Nicholas Reaction) 323
43.5.2.1.3 Method 3: Ring-Contraction Reactions 324
43.5.2.1.3.1 Variation 1: Wittig Rearrangement 324
43.5.2.1.3.2 Variation 2: Photochemical Sulfur Dioxide Extrusion 324
43.5.2.1.4 Method 4: Alkene Formation Post Ring Closure 325
43.5.2.1.4.1 Variation 1: Elimination Reactions with Base 325
43.5.2.1.4.2 Variation 2: Decomplexation Reactions 325
43.5.2.1.5 Method 5: Alkyne Formation Post Ring Closure 326
43.5.3 Product Subclass 3: Cyclodecenynes 326
43.5.3.1 Synthesis of Product Subclass 3 327
43.5.3.1.1 Method 1: Base-Mediated Ring Closure by Alkynylmetal Condensations with Carbonyl Groups and Related Electrophiles 327
43.5.3.1.1.1 Variation 1: Aldol Condensation Reaction 330
43.5.3.1.1.2 Variation 2: Carbene Insertion--Elimination Reaction 331
43.5.3.1.1.3 Variation 3: Chromium(II) Chloride/Nickel(II) Chloride Condensation Reactions 331
43.5.3.1.1.4 Variation 4: Alkynyltrimethylsilane Condensations with Fluoride Ion 334
43.5.3.1.1.5 Variation 5: Condensations from Enol Ethers with a Lewis Acid 335
43.5.3.1.2 Method 2: Ring Closure by Condensation of Alkyne--Hexacarbonyldicobalt Complexes (Nicholas Reaction) 335
43.5.3.1.2.1 Variation 1: With In Situ Enolization 337
43.5.3.1.3 Method 3: Pinacol Ring-Closure Reactions 338
43.5.3.1.3.1 Variation 1: Pinacol Ring Closure--Alkene Formation 339
43.5.3.1.4 Method 4: Palladium Coupling Reactions 340
43.5.3.1.4.1 Variation 1: Double Palladium Coupling Reactions 341
43.5.3.1.5 Method 5: Ring-Contraction Reactions 342
43.5.3.1.5.1 Variation 1: Sulfur Dioxide Extrusion 342
43.5.3.1.6 Method 6: Intramolecular Diels--Alder Reactions 343
43.5.3.1.7 Method 7: Alkene Formation Post Ring Closure 344
43.5.3.1.7.1 Variation 1: Thermolysis Reactions 344
43.5.3.1.7.2 Variation 2: Enzyme-Mediated Reactions 345
43.5.3.1.7.3 Variation 3: Allylic Rearrangement Reactions 345
43.5.3.1.7.4 Variation 4: Dehydrogenation Reactions 346
43.5.3.1.7.5 Variation 5: Retro-Diels--Alder Reactions 346
43.5.3.1.8 Method 8: Alkyne Formation Post Ring Closure 347
43.5.3.1.9 Method 9: Ruthenium Coupling Reactions 347
43.5.4 Product Subclass 4: Cycloundecenynes 348
43.5.4.1 Synthesis of Product Subclass 4 348
43.5.4.1.1 Method 1: Ring Closure by Alkynylmetal Condensations with Carbonyl Groups and Related Electrophiles 348
43.5.4.1.1.1 Variation 1: Chromium(II) Chloride/Nickel(II) Chloride Condensations 349
43.5.4.1.2 Method 2: Ring Closure by Condensation of Alkyne--Hexacarbonyldicobalt Complexes (Nicholas Reaction) 349
43.5.4.1.3 Method 3: Palladium Coupling Reactions 350
43.5.4.1.4 Method 4: Ring-Contraction Reactions 350
43.5.4.1.4.1 Variation 1: Sulfur Dioxide Extrusion 350
43.5.4.1.4.2 Variation 2: Sigmatropic Rearrangements 351
43.5.4.1.5 Method 5: Intramolecular Diels--Alder Reactions 352
43.5.4.1.6 Method 6: Alkene Formation Post Ring Closure 352
43.5.4.1.6.1 Variation 1: Thermolysis Reactions 352
43.5.5 Product Subclass 5: Cyclododecenynes 353
43.5.5.1 Synthesis of Product Subclass 5 353
43.5.5.1.1 Method 1: Ring Closure by Chromium(II) Chloride/Nickel(II) Chloride Condensations 353
43.5.5.1.2 Method 2: Copper Coupling Reactions 354
43.5.5.1.3 Method 3: Ruthenium Coupling Reactions 355
43.5.5.1.4 Method 4: Ring-Contraction Reactions 355
43.5.5.1.4.1 Variation 1: Sulfur Dioxide Extrusion 355
43.5.5.1.5 Method 5: Alkene Formation Post Ring Closure 356
43.5.5.1.5.1 Variation 1: Thermolysis Reactions 356
43.5.5.1.6 Method 6: Alkyne Formation Post Ring Closure 356
43.5.6 Product Subclass 6: Cyclotridecenynes 357
43.5.6.1 Synthesis of Product Subclass 6 357
43.5.6.1.1 Method 1: Ring-Contraction Reactions 357
43.5.6.1.1.1 Variation 1: Sulfur Dioxide Extrusion 357
43.5.6.1.1.2 Variation 2: Sigmatropic Rearrangement Reaction 357
43.5.7 Product Subclass 7: Cyclotetradecenynes 358
43.5.7.1 Synthesis of Product Subclass 7 358
43.5.7.1.1 Method 1: Ring-Contraction Reactions 358
43.5.7.1.1.1 Variation 1: Sulfur Dioxide Extrusion 358
43.5.7.1.2 Method 2: Copper Coupling Reactions 358
43.5.7.1.3 Method 3: Ruthenium Coupling Reactions 359
43.5.8 Product Subclass 8: Cyclopentadecenynes 359
43.5.8.1 Synthesis of Product Subclass 8 359
43.5.8.1.1 Method 1: Ring-Contraction Reactions 359
43.5.8.1.1.1 Variation 1: Sulfur Dioxide Extrusion 359
43.5.8.1.2 Method 2: Alkyne Formation Post Ring Closure 360
43.5.9 Product Subclass 9: Cyclohexadecenynes 360
43.5.9.1 Synthesis of Product Subclass 9 360
43.5.9.1.1 Method 1: Ruthenium Coupling Reactions 360
43.5.9.1.2 Method 2: Ring-Contraction Reactions 361
43.5.10 Product Subclass 10: Cyclophanes and Annulenes with Enyne Bridge Components 361
43.5.10.1 Synthesis of Product Subclass 10 361
43.5.10.1.1 Method 1: Copper Coupling Reactions 361
43.5.10.1.2 Method 2: Palladium Coupling Reactions 367
43.6 Product Class 6: Acyclic Arylalkynes 374
43.6.1 Synthesis of Product Class 6 376
43.6.1.1 Synthesis from Metalated Arenes and Haloalkynes 376
43.6.1.1.1 Method 1: Cross Coupling of Aryl Cuprates and Haloalkynes 376
43.6.1.1.2 Method 2: Cross Coupling of Aryl Stannanes and Haloalkynes 377
43.6.1.2 Synthesis from Haloarenes and Metal Alkynides 378
43.6.1.2.1 Method 1: Palladium-Catalyzed Cross Coupling with Tin Alkynides 378
43.6.1.2.2 Method 2: Palladium-Catalyzed Cross Coupling with Zinc Alkynides 379
43.6.1.2.3 Method 3: Palladium-Catalyzed Cross Coupling with Copper Alkynides (The Stephens--Castro Reaction) 380
43.6.1.2.4 Method 4: Palladium-Catalyzed Cross Coupling with Silicon Alkynides 381
43.6.1.2.5 Method 5: Palladium-Catalyzed Cross Coupling with Aluminum Alkynides 382
43.6.1.2.6 Method 6: Palladium-Catalyzed Cross Coupling with Magnesium Alkynides (Kumada--Corriu-Type Coupling) 384
43.6.1.2.7 Method 7: Palladium-Catalyzed Cross Coupling with Boron Alkynides 384
43.6.1.3 Synthesis from Haloarenes and Terminal Alkynes 386
43.6.1.3.1 Method 1: Silver/Palladium-Catalyzed Cross Coupling of Haloarenes and Terminal Alkynes 386
43.6.1.3.2 Method 2: Indium/Palladium-Catalyzed Cross Coupling of Haloarenes and Terminal Alkynes 387
43.6.1.3.3 Method 3: Zinc/Palladium-Catalyzed Cross Coupling of Haloarenes and Terminal Alkynes 388
43.6.1.3.4 Method 4: Copper/Palladium-Catalyzed Cross Coupling of Haloarenes and Terminal Alkynes (The Sonogashira--Hagihara Cross-Coupling Reaction) 388
43.6.1.3.4.1 Variation 1: Sonogashira Cross-Coupling Reactions for Bromoarenes Using Specially Designed Ligands 390
43.6.1.3.4.2 Variation 2: Sonogashira Reaction under Microwave-Irradiation Conditions 391
43.6.1.3.4.3 Variation 3: Sonogashira Reaction under Phase-Transfer Conditions 392
43.6.1.3.4.4 Variation 4: Sonogashira Reactions in Water or Aqueous Mixtures of Solvents 393
43.6.1.3.5 Method 5: Palladium-Catalyzed Cross Coupling (Copper-Free Sonogashira Reaction) 394
43.6.1.3.5.1 Variation 1: Domino Halogen-Exchange (Halex) and Copper-Free Sonogashira Reaction 397
43.6.1.3.5.2 Variation 2: Palladium-Catalyzed Cross Coupling in Water 398
43.6.1.3.5.3 Variation 3: Palladium-Catalyzed Cross Coupling in Ionic Liquids 399
43.6.1.3.5.4 Variation 4: Palladium-Catalyzed Coupling Using Palladium(0) Nanoparticles 400
43.6.1.3.5.5 Variation 5: Solvent-Free Palladium-Catalyzed Cross Coupling 401
43.6.1.3.5.6 Variation 6: Palladium-Catalyzed Cross Coupling Using Microwave Irradiation 402
43.6.1.3.6 Method 6: Metal-Free Cross Coupling (Metal-Free Sonogashira Reaction) 403
43.6.1.4 Synthesis by Elimination 404
43.6.1.4.1 Method 1: Elimination of Arylalkanes 404
43.6.1.4.1.1 Variation 1: Halogenation Followed by Double Dehydrohalogenation 404
43.6.1.4.1.2 Variation 2: Benzylation Followed by Double Dehydrohalogenation 405
43.6.1.4.2 Method 2: Elimination from Vinylarenes 405
43.6.1.4.2.1 Variation 1: 1,1-Dehydrohalogenation and 1,1-Dehalogenation 405
43.6.1.4.3 Method 3: Elimination of Carbon Monoxide from Cyclopropenones 406
43.6.1.4.4 Method 4: Elimination of Dinitrogen from Five-Membered Heterocycles 408
43.6.1.4.5 Method 5: Synthesis from Aromatic Aldehydes 409
43.6.1.4.5.1 Variation 1: Alkenylation and Subsequent Elimination 409
43.6.1.4.5.2 Variation 2: Corey--Fuchs Modification 410
43.6.1.4.5.3 Variation 3: Seyferth--Gilbert Modification 411
43.6.1.4.5.4 Variation 4: Bestmann--Ohira Modification 412
43.6.1.5 Synthesis by Metathesis Reactions 414
43.6.1.5.1 Method 1: Alkyne Homodimerization 414
43.6.1.5.2 Method 2: Alkyne Cross Metathesis 415
43.6.1.5.3 Method 3: Ring-Closure Alkyne Metathesis 415
43.6.1.5.4 Method 4: Acyclic Diyne Metathesis 416
43.7 Product Class 7: Cyclic Arylalkynes 422
43.7.1 Synthesis of Product Class 7 422
43.7.1.1 Formation of Triple-Bond-Containing Rings by C--C Bond Formation 422
43.7.1.1.1 Method 1: Formation of C(sp3)--C(sp3) Bonds by Wurtz-Type Coupling Reactions 422
43.7.1.1.2 Method 2: Formation of C(sp3)--C(sp) Bonds by Nucleophilic Substitution Reactions of Metal Acetylides with Haloalkanes 423
43.7.1.1.3 Method 3: Formation of C(sp2)--C(sp2) Bonds by Copper(II)-Catalyzed Coupling Reactions of Aryllithiums 424
43.7.1.1.4 Method 4: Formation of C(sp2)--C(sp) Bonds by Transition-Metal-Catalyzed Cross-Coupling Reactions 425
43.7.1.1.4.1 Variation 1: Stephens--Castro Reactions of Copper(I) Acetylides with Aryl and Vinyl Halides 425
43.7.1.1.4.2 Variation 2: Copper(I)-Catalyzed Coupling of Acetylenes with Aryl Halides 427
43.7.1.1.4.3 Variation 3: Hagihara--Sonogashira Reactions of Acetylenes with Aryl and Vinyl Halides 428
43.7.1.1.4.4 Variation 4: Palladium(0)-Catalyzed Cross-Coupling Reactions of Acetylenes with Vinyl Trifluoromethanesulfonates 430
43.7.1.1.4.5 Variation 5: In Situ Deprotection--Palladium(0)-Catalyzed Cross-Coupling Reactions 431
43.7.1.1.5 Method 5: Formation of C(sp)--C(sp) Bonds by Transition-Metal-Mediated Oxidative Coupling Reactions 434
43.7.1.1.5.1 Variation 1: Hay Coupling Reactions 435
43.7.1.1.5.2 Variation 2: Eglinton Coupling Reactions 437
43.7.1.1.5.3 Variation 3: Breslow's Modification of Eglinton Coupling Reactions 441
43.7.1.1.5.4 Variation 4: Preparation of Macrocyclic Arylacetylenes Using Covalently Bound Templates 444
43.7.1.1.5.5 Variation 5: In Situ Deprotection--Eglinton Type Coupling Reactions 445
43.7.1.1.5.6 Variation 6: Palladium(II)-Catalyzed Oxidative Coupling Reactions of Terminal Alkynes 446
43.7.1.1.5.7 Variation 7: Palladium(0)-Catalyzed Cross Coupling of Terminal Alkynes with Bromoalkynes 448
43.7.1.1.6 Method 6: Alkyne Metathesis 449
43.7.1.1.7 Method 7: Cycloaddition Reaction of Cumulenic Quinodimethanes 452
43.7.1.2 Formation of Triple-Bond-Containing Rings by Elimination Reactions 452
43.7.1.2.1 Method 1: Double Dehydrohalogenation Reactions 453
43.7.1.2.2 Method 2: Double Elimination Reactions of ß-Substituted Sulfones 455
43.7.1.2.3 Method 3: Oxidative Fragmentation of Bishydrazones 456
43.7.1.3 Formation of Aromatic Rings 457
43.7.1.3.1 Method 1: Metal-Catalyzed Cyclotrimerizations 457
43.7.1.3.2 Method 2: Palladium(0)-Catalyzed Enyne--Diyne [4 + 2] Cross-Benzannulation 458
43.7.1.3.3 Method 3: Valence Isomerization 459
43.8 Product Class 8: Linear Alkynes 464
43.8.1 Synthesis by Elimination 464
43.8.1.1 1,2-Elimination 464
43.8.1.1.1 Method 1: Dehydrogenation of Alkanes and Alkenes 464
43.8.1.1.2 Method 2: Dehydrohalogenation of Vicinal Dihaloalkanes 466
43.8.1.1.3 Method 3: Elimination Reactions of Heteroatom-Substituted Vinyl Derivatives 467
43.8.1.1.4 Method 4: Elimination of Vicinal Heteroatom Groups 470
43.8.1.2 1,1-Elimination 471
43.8.1.2.1 Method 1: Dehalogenation of 1,1-Dihaloalkenes (Corey--Fuchs Reaction) 471
43.8.1.2.1.1 Variation 1: Normal Corey--Fuchs Reactions 471
43.8.1.2.1.2 Variation 2: Modified Corey--Fuchs Reactions 473
43.8.1.2.2 Method 2: Rearrangement of Vinyl Carbenoids (Fritsch--Buttenburg--Wiechell Rearrangement) 474
43.8.1.3 Thermolytic Elimination 476
43.8.1.3.1 Method 1: Elimination Reactions of Vinyl Selenoxides 476
43.8.1.3.2 Method 2: Elimination Reactions of Thiirene Dioxides (Ramberg--Bäcklund Reaction), Phosphirene Oxides, and a-Oxo Ylides 477
43.8.1.3.3 Method 3: Elimination Reactions of Cyclic 1,2,3-Selenadiazoles 479
43.8.1.4 Photolytic Elimination 480
43.8.1.4.1 Method 1: Cycloreversion of Fused Benzocyclobutene Derivatives 480
43.8.1.4.2 Method 2: Elimination of Carbon Monoxide from Cyclopropenone and Cyclobutenedione Derivatives 481
43.8.1.5 Double Elimination Reactions of 1,2-Disubstituted Motifs from Aldol-Type Condensations 483
43.8.1.5.1 Method 1: Wittig Reactions of (Halomethylene)phosphoranes and (Halomethyl)phosphonates 483
43.8.1.5.1.1 Variation 1: Wittig Reactions of (a-Halomethylene)phosphoranes 483
43.8.1.5.1.2 Variation 2: Wittig Reactions of (Halomethyl)phosphonates 484
43.8.1.5.2 Method 2: Synthesis Using a-Diazo ß-Oxo Phosphonates (Bestmann--Ohira Reagent) 485
43.8.1.5.2.1 Variation 1: One-Pot Oxidation of Benzyl Alcohols and Subsequent Treatment with the Bestmann--Ohira Reagent 487
43.8.1.5.2.2 Variation 2: Reaction Using a Gel-Supported Bestmann--Ohira Reagent 488
43.8.1.5.3 Method 3: Aldol Condensation of a-Sulfonyl Anions with Aldehydes, Followed by Double Elimination 490
43.8.1.5.3.1 Variation 1: Double Elimination of Acetoxy and Siloxy Derivatives 490
43.8.1.5.3.2 Variation 2: Double Elimination Involving Peterson Elimination 490
43.8.1.5.3.3 Variation 3: Double Elimination Using a Chlorophosphonate as a Trapping Agent 491
43.8.1.6 Oxidative Elimination 492
43.8.1.6.1 Method 1: Oxidative Elimination of 1,2-Bis(hydrazones) 492
43.8.1.6.2 Method 2: Oxidative Elimination of Vinylstannanes 494
43.8.2 Synthesis by Rearrangement 498
43.8.2.1 Thermal Rearrangements 498
43.8.2.1.1 Method 1: Thermal Isomerization of Cyclopropenes 498
43.8.2.1.2 Method 2: Cope and Claisen Rearrangements and Related Reactions 500
43.8.2.1.3 Method 3: Ene Reaction and Related Conversions 505
43.8.2.1.4 Method 4: Rearrangement of Alkylidenecarbenes 507
43.8.2.1.5 Method 5: Fritsch--Buttenberg--Wiechell Rearrangement and Related Carbenoid Reactions 512
43.8.2.1.5.1 Variation 1: Fritsch--Buttenberg--Wiechell Rearrangement of 1-Haloalkenes and 1,1-Dihaloalkenes 512
43.8.2.1.5.2 Variation 2: Photo-Fritsch--Buttenberg--Wiechell Rearrangement 515
43.8.2.1.5.3 Variation 3: Electrochemical-Fritsch--Buttenberg--Wiechell Rearrangement 516
43.8.2.1.5.4 Variation 4: Carbenoid Rearrangement of Other Metalated Species 517
43.8.2.1.5.5 Variation 5: Carbenoid Rearrangements of a-Halo-ß,ß-Diarylacrylic Acids and a-Halocinnamic Acids 518
43.8.2.1.5.6 Variation 6: Carbenoid Rearrangement of 3-Nitrosooxazolidin-2-ones and Related Compounds 520
43.8.2.1.5.7 Variation 7: Carbenoid Rearrangement of 5-Methyltetrazoles 521
43.8.2.1.5.8 Variation 8: Carbenoid Rearrangement of Ketene Adducts with Phosphites 522
43.8.2.1.6 Method 6: Miscellaneous Thermal Rearrangements 522
43.8.2.1.6.1 Variation 1: Alkynes by a Hydrogen-Shift Reaction 522
43.8.2.1.6.2 Variation 2: Alkynes by Retro-Diels--Alder Reaction 523
43.8.2.1.6.3 Variation 3: Alkynes by [2,3]-Sigmatropic Rearrangement 524
43.8.2.2 Photochemical Rearrangements 524
43.8.2.2.1 Method 1: Photochemical Rearrangement of Allenes 524
43.8.2.2.2 Method 2: Photochemical Vinylidenecarbene Rearrangements 526
43.8.2.2.3 Method 3: Photochemical Rearrangement of Cyclopropenes 527
43.8.2.2.4 Method 4: Formal Cycloreversion of Cyclobutenes 528
43.8.2.3 Base-Catalyzed Rearrangements 529
43.8.2.3.1 Method 1: Alk-2-ynes by Base-Catalyzed Rearrangement of Alk-1-ynes 529
43.8.2.3.2 Method 2: Alk-1-ynes by Base-Catalyzed Rearrangement of Internal Alkynes 532
43.8.2.3.3 Method 3: Base-Catalyzed Rearrangement of Internal Alkynes 535
43.8.2.3.4 Method 4: Base-Catalyzed Rearrangement of Allenes 536
43.8.2.4 Acid-Catalyzed Rearrangements 538
43.8.2.4.1 Method 1: Acid-Catalyzed Rearrangement of Alkynes and Allenes 539
43.8.2.4.2 Method 2: Dienol--Benzene and Dienone--Benzene Rearrangements 540
43.8.2.4.3 Method 3: Anomeric Oxygen-to-Carbon Rearrangement of Alkynyltributylstannanes 543
43.8.2.5 Metal-Catalyzed Rearrangements 545
43.8.2.5.1 Method 1: Alkyne Metathesis 545
43.8.2.5.2 Method 2: Gold-Catalyzed Rearrangements 553
43.8.2.5.3 Method 3: Tandem Zinc-Promoted Brook Rearrangement and Ene--Allene Cyclization 554
43.8.2.5.4 Method 4: Metal-Catalyzed Rearrangements with Other Metals 556
43.8.2.6 Coarctate Rearrangements 561
43.8.2.6.1 Method 1: Diazirine Rearrangement 562
43.8.2.6.2 Method 2: Spiroozonide Conversion 562
43.8.2.6.3 Method 3: Rearrangement of Cyclopropylcarbenes 563
43.8.2.6.4 Method 4: The Eschenmoser--Tanabe Fragmentation of Epoxy Ketones 566
43.8.2.6.5 Method 5: Fragmentation of 1,3,4-Oxadiazolidin-2-ones 572
43.8.2.6.6 Method 6: Cyclopropenylcarbene Fragmentation 573
43.8.2.6.7 Method 7: Furfurylidene Rearrangement 575
43.8.2.7 Enzyme-Catalyzed Rearrangements 576
43.8.3 Synthesis from Other Alkynes 584
43.8.3.1 Conversion into an Alkynylmetal Followed by Reaction with an Electrophile 584
43.8.3.1.1 Method 1: Reaction of an Alkynyllithium with an Alkyl Halide or Equivalent 584
43.8.3.1.1.1 Variation 1: With a Chloroalkane 584
43.8.3.1.1.2 Variation 2: With a Bromoalkane 587
43.8.3.1.1.3 Variation 3: With an Iodoalkane 598
43.8.3.1.1.4 Variation 4: With a Dialkyl Sulfate 606
43.8.3.1.1.5 Variation 5: With an Alkyl Methanesulfonate 607
43.8.3.1.1.6 Variation 6: With an Alkyl Arenesulfonate 608
43.8.3.1.1.7 Variation 7: With an Alkyl Trifluoromethanesulfonate 610
43.8.3.1.1.8 Variation 8: With an Allyl Ester or Carbonate 611
43.8.3.1.1.9 Variation 9: With an Alcohol 612
43.8.3.1.1.10 Variation 10: With a Trialkylborane 612
43.8.3.1.1.11 Variation 11: With an Alkylzirconium Reagent 614
43.8.3.1.2 Method 2: Reaction of an Alkynylsodium with an Alkyl Halide or Equivalent 615
43.8.3.1.2.1 Variation 1: With a Chloroalkane 615
43.8.3.1.2.2 Variation 2: With a Bromoalkane 615
43.8.3.1.2.3 Variation 3: With an Iodoalkane 618
43.8.3.1.2.4 Variation 4: With a Dialkyl Sulfate 619
43.8.3.1.2.5 Variation 5: With an Alkyl Arenesulfonate 620
43.8.3.1.3 Method 3: Reaction of an Alkynylpotassium with an Alkyl Halide or Equivalent 620
43.8.3.1.4 Method 4: Reaction of an Alkynyl Grignard Reagent with an Alkyl Halide or Equivalent 620
43.8.3.1.4.1 Variation 1: With a Chloroalkane 620
43.8.3.1.4.2 Variation 2: With a Bromoalkane 622
43.8.3.1.4.3 Variation 3: With an Iodoalkane 623
43.8.3.1.4.4 Variation 4: With a Dialkyl Sulfate 624
43.8.3.1.4.5 Variation 5: With an Alkyl Methanesulfonate 625
43.8.3.1.4.6 Variation 6: With an Alkyl Arenesulfonate 626
43.8.3.1.4.7 Variation 7: With an Allyl Ester 626
43.8.3.1.4.8 Variation 8: With an Alkylzirconium Reagent 627
43.8.3.1.5 Method 5: Reaction of an Alkynylcalcium with an Alkyl Halide or Equivalent 628
43.8.3.1.6 Method 6: Reaction of an Alkynylbarium with an Alkyl Halide or Equivalent 628
43.8.3.1.7 Method 7: Palladium/Copper-Catalyzed Reaction of an Alk-1-yne with an Alkyl Halide or Equivalent 628
43.8.3.1.7.1 Variation 1: With a Chloroalkane 628
43.8.3.1.7.2 Variation 2: With a Bromoalkane 630
43.8.3.1.7.3 Variation 3: With an Iodoalkane 634
43.8.3.1.7.4 Variation 4: With an Alkyl Methanesulfonate 634
43.8.3.1.7.5 Variation 5: With an Alkyl Arenesulfonate 635
43.8.3.1.7.6 Variation 6: With a Trialkylborane 635
43.8.3.1.8 Method 8: Reaction of an Alkynylcopper with an Alkyl Halide or Equivalent 635
43.8.3.1.8.1 Variation 1: With a Bromoalkane 635
43.8.3.1.9 Method 9: Reaction of an Alkynylmercury with an Alkyl Halide or Equivalent 636
43.8.3.1.9.1 Variation 1: With a Bromoalkane 636
43.8.3.1.9.2 Variation 2: With an Iodoalkane 636
43.8.3.1.10 Method 10: Reaction of an Alkynylboron Reagent with an Alkyl Halide or Equivalent 636
43.8.3.1.11 Method 11: Reaction of an Alkynylaluminum Reagent with an Alkyl Halide or Equivalent 637
43.8.3.1.11.1 Variation 1: With a Chloroalkane 637
43.8.3.1.11.2 Variation 2: With a Bromoalkane 638
43.8.3.1.11.3 Variation 3: With an Alkyl Methanesulfonate 638
43.8.3.1.11.4 Variation 4: With an Alkyl Phenyl Sulfone 638
43.8.3.1.11.5 Variation 5: With a Propiolactone 639
43.8.3.1.12 Method 12: Reaction of a (Trialkylsilyl)alkyne with an Alkyl Halide or Equivalent 640
43.8.3.1.12.1 Variation 1: With a Chloroalkane 640
43.8.3.1.13 Method 13: Reaction of an Alkynyllithium with an Allene or Other Alkene 640
43.8.3.1.13.1 Variation 1: With a Bromoallene 640
43.8.3.2 Nucleophilic Substitution by an Organometallic Reagent at an Alkyne Derivative 641
43.8.3.2.1 Method 1: Reaction of a Chloroalkyne with an Organometallic Reagent 641
43.8.3.2.1.1 Variation 1: With a Silyl Enol Ether 641
43.8.3.2.1.2 Variation 2: With an Organozirconium Reagent 641
43.8.3.2.2 Method 2: Reaction of a Bromoalkyne with an Organometallic Reagent 642
43.8.3.2.2.1 Variation 1: With a Grignard Reagent 642
43.8.3.2.2.2 Variation 2: With an Organozinc Reagent 642
43.8.3.2.2.3 Variation 3: With a Trialkylaluminum Reagent 645
43.8.3.2.2.4 Variation 4: With an Organozirconium Reagent 646
43.8.3.2.3 Method 3: Reaction of an Iodoalkyne with an Organometallic Reagent 646
43.8.3.2.3.1 Variation 1: With a Grignard Reagent 646
43.8.3.2.3.2 Variation 2: With an Organozinc Reagent 647
43.8.3.2.3.3 Variation 3: With an Organocopper Reagent 647
43.8.3.2.3.4 Variation 4: With an Organozirconium Reagent 648
43.8.3.2.4 Method 4: Reaction of an Alkynyl Aryl Sulfone with an Alkyllithium 649
43.8.3.3 Reactions Involving neither Electrophilic nor Nucleophilic Attack 649
43.8.3.3.1 Method 1: Reaction of an Alkynyl Trifluoromethyl Sulfone with an Alkane 649
43.8.3.3.2 Method 2: Reaction of an Alkynyl Phenyl Sulfone with a B-Alkylcatecholborane 650
43.8.3.3.3 Method 3: Ruthenium-Catalyzed Reaction of an Alkyne with a 1,3-Diene 651
43.8.3.3.4 Method 4: Nickel-Catalyzed Reaction of an Alkyne with an Allyl Ester 651
43.8.3.3.5 Method 5: Palladium-Catalyzed Oxidative Coupling of an Alkynylstannane Reagent with an Alkylzinc Reagent 652
43.9 Product Class 9: Cycloalkynes 660
43.9.1 Synthesis of Product Class 9 660
43.9.1.1 Method 1: Ring-Closure Reactions 660
43.9.1.1.1 Variation 1: Using sp-Carbon Nucleophiles 660
43.9.1.1.2 Variation 2: Using sp3-Carbon Nucleophiles 663
43.9.1.1.3 Variation 3: Using Chalcogen Nucleophiles 667
43.9.1.1.4 Variation 4: Using Nitrogen Nucleophiles 668
43.9.1.1.5 Variation 5: Alkyne Metathesis 673
43.9.1.2 Method 2: Elimination and Fragmentation Reactions 677
43.9.1.2.1 Variation 1: 1,2-Elimination Reactions 677
43.9.1.2.2 Variation 2: Cycloelimination Reactions 682
43.9.1.2.3 Variation 3: Eschenmoser Fragmentation 685
43.9.1.3 Method 3: Isomerization Reactions 686
43.9.1.3.1 Variation 1: Pericyclic Ring-Opening Reactions 686
43.9.1.4 Method 4: Ring-Enlargement Reactions 687
43.9.1.4.1 Variation 1: Fritsch--Buttenberg--Wiechell Rearrangement 687
43.9.1.4.2 Variation 2: Carbene Reactions 687
43.9.1.5 Method 5: Decomplexation Reactions 689
43.9.1.5.1 Variation 1: Cleavage of Hexacarbonyldicobalt Complexes 689
43.9.2 Applications of Product Class 9 in Organic Synthesis 690
43.9.2.1 Method 1: Reactions of Cyclic Alkynes with Organometallic Reagents 690
43.9.2.1.1 Variation 1: Reactions of Cyclic Alkynes with (.5-Cyclopentadienyl)cobalt(I) 690
43.9.2.1.2 Variation 2: Reactions of Cyclic Alkynes with Aluminum Trichloride 692
Keyword Index 698
Author Index 736
Abbreviations 768