Science of synthesis: Houben-Weyl methods of molecular transformations 23 = Category 3, Compounds with four and three carbon-heteroatom bonds Three carbon-heteroatom bonds: ketenes and derivatives
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Book |
| Language: | English |
| Published: |
Stuttgart [u.a.]
Thieme
2006
|
| Online Access: | Inhaltsverzeichnis |
| Physical Description: | XXXIV, 1054 Seiten Illustrationen 26 cm |
| ISBN: | 3131187417 1588902005 9783131187413 |
Staff View
MARC
| LEADER | 00000nam a22000008cc4500 | ||
|---|---|---|---|
| 001 | BV021603053 | ||
| 003 | DE-604 | ||
| 005 | 20230823 | ||
| 007 | t | ||
| 008 | 060601s2006 a||| |||| 00||| eng d | ||
| 020 | |a 3131187417 |9 3-13-118741-7 | ||
| 020 | |a 1588902005 |9 1-58890-200-5 | ||
| 020 | |a 9783131187413 |9 978-31-3-118741-3 | ||
| 035 | |a (OCoLC)633828299 | ||
| 035 | |a (DE-599)BVBBV021603053 | ||
| 040 | |a DE-604 |b ger |e rda | ||
| 041 | 0 | |a eng | |
| 049 | |a DE-355 |a DE-20 |a DE-19 |a DE-210 |a DE-91G |a DE-188 |a DE-11 | ||
| 100 | 1 | |a Aizpurua, J. M. |4 aut | |
| 245 | 1 | 0 | |a Science of synthesis |b Houben-Weyl methods of molecular transformations |n 23 = Category 3, Compounds with four and three carbon-heteroatom bonds |p Three carbon-heteroatom bonds: ketenes and derivatives |c ed. board: D. Bellus ... |
| 264 | 1 | |a Stuttgart [u.a.] |b Thieme |c 2006 | |
| 300 | |a XXXIV, 1054 Seiten |b Illustrationen |c 26 cm | ||
| 336 | |b txt |2 rdacontent | ||
| 337 | |b n |2 rdamedia | ||
| 338 | |b nc |2 rdacarrier | ||
| 700 | 1 | |a Bellus, Daniel |e Sonstige |4 oth | |
| 700 | 1 | |a Danheiser, R. L. |4 edt | |
| 700 | 1 | |a Houben, Josef |d 1875-1940 |e Sonstige |0 (DE-588)117013870 |4 oth | |
| 773 | 0 | 8 | |w (DE-604)BV013247070 |g 23 |
| 776 | 0 | 8 | |i Erscheint auch als |n Online-Ausgabe |z 978-31-3-183751-6 |
| 856 | 4 | 2 | |m HBZ Datenaustausch |q application/pdf |u http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=014818364&sequence=000002&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA |3 Inhaltsverzeichnis |
| 943 | 1 | |a oai:aleph.bib-bvb.de:BVB01-014818364 | |
Record in the Search Index
| _version_ | 1807863421188702208 |
|---|---|
| adam_text |
_ ^ ^ ^ | ^ ix
Table of Contents
Introduction
R. L. Danheiser
Introduction 1
23.1 Product Class 1: Ketene
T. T. Tidwell
23.1 Product Class 1: Ketene 15
23.1.1 Synthesis of Product Class 1 18
23.1.1.1 Method 1: Ketene from Acetic Acid, Acid Anhydrides, and Esters 19
23.1.1.2 Method 2: Dehydrohalogenation of Acetyl Halides 19
23.1.1.2.1 Variation 1: lonization of Acetyl Halides to Acylium Ions and Deprotonation 21
23.1.1.3 Method 3: Pyrolysis of Ketene Dimer 22
23.1.1.4 Method 4: Photolysis of Cyclobutanones and Thermolysis 22
23.1.1.5 Method 5: Dehalogenation of Haloacetyl Halides 23
23.1.1.6 Method 6: Pyrolysis of Acetone 24
23.1.1.7 Method 7: Wolff Rearrangement of Diazoacetaldehyde 24
23.1.1.8 Method 8: Elimination from Alkynyl Ethers 25
23.1.2 Applications of Product Class 1 in Organic Synthesis 26
23.1.2.1 Method 1: Nucleophilic Addition to Ketene 26
23.1.2.1.1 Variation 1: Enol Acetates from the Reaction of Ketene with Aldehydes
and Ketones 28
23.1.2.2 Method 2: Electrophilic and Radical Additions to Ketene 29
23.1.2.3 Method 3: Dimerization by [2 + 2] Cycloaddition 32
23.1.2.4 Method 4: [2 + 2] Cycloaddition of Ketene with Alkenes and Dienes 32
23.1.2.5 Method 5: [2 + 2] Cycloaddition of Ketene with Alkynes 34
23.1.2.6 Method 6: [2 + 2] Cycloaddition of Ketene with Imines 35
23.1.2.7 Method 7: [2 + 2] and [4+2] Cycloaddition of Ketene with Carbonyl Croups 36
23.1.2.7.1 Variation 1: [3 Hydroxy Esters by Titanium Alkoxide Induced Addition
of Carbonyl Compounds to Ketene 42
23.1.2.8 Method 8: [2 + 2] Cycloaddition of Ketene with Azobenzenes 42
23.1.2.9 Method 9: [2 + 1] Cycloaddition of Ketene with Sulfur Dioxide 43
23.1.2.10 Method 10: [2 +1 ] Cycloaddition of Ketene with Diazomethane 44
23.1.2.11 Method 11: [4 + 2] Cycloaddition of Ketene with Heterodienes 44
23.1.2.12 Method 12: Wittig Reaction of Ketene with a Chiral Phosphorane 45
23.1.2.13 Method 13: Dimetal Ketenides from Ketene and Metal Salts 45
23.1.2.14 Method 14: Decarbonylation of Ketene 46
X Table of Contents
23.2 Product Class 2: Silylketenes
D. M. George and R. L. Danheiser
23.2 Product Class 2: Silylketenes 53
23.2.1 Product Subclass 1: Silyl Substituted Aldoketenes 54
23.2.1.1 Synthesis of Product Subclass 1 54
23.2.1.1.1 Method 1: Dehydrohalogenation of Acyl Halides 54
23.2.1.1.2 Method 2: Dehydration of Silylacetic Acids 55
23.2.1.1.3 Method 3: Thermolysis of 1 Alkoxy 2 silylacetylenes 55
23.2.1.1.4 Method 4: 1,3 Silyl Shift of (Trimethylsiloxy)acetylene 57
23.2.1.1.5 Method 5: Thermolysis of Silylacetic Anhydrides 57
23.2.1.2 Applications of Product Subclass 1 in Organic Synthesis 58
23.2.1.2.1 Methodi: [2 + 2] Cycloadditions Leading to fRactones 58
23JM.2.2 Method2: [2 + 2] Cycloadditions Leading to {5 Lactams 64
23JU.2.3 Method 3: [2 + 2] Cycloadditions Leading to Cyclobutanones 65
23.2.1.2.4 Method 4: Formation of Allenes via Wittig Reaction with Phosphorus
Ylides 65
23.2.1.2.5 Method 5: Formation of Ketenimines via Reaction with
Iminophosphoranes 66
23.2.1.2.6 Method 6: Formation of Cyclopropanones and Cyclobutanones
via Reaction with Diazo Compounds 67
23.2.1.2.7 Method 7: Formation of a Silyl Ketones 68
23.2.1.2.8 Method 8: Formation of 2H 1 Benzopyran 2 ones from Phenols 70
23.2.1.2.9 Method 9: (Trimethylsilyl)acetylation of Alcohols and Amines 71
23J.2 Product Subclass 2: (Silyl)(trialkylmetal)ketenes 72
23.2.2.1 Synthesis of Product Subclass 2 72
23.2.2.1.1 Method 1: Elimination from (Silyl)(trialkylmetal)acetates 72
23.2.2.1.2 Method 2: Trapping of Lithium 2 Lithioacetylen 1 olate Generated
from 2 Phenyl 2,3 dihydrofurans or 3 Phenylisoxazoles 72
23.2.2.1.3 Method 3: Carbonylation and Trapping of Lithiated Diazo(trimethyl
silyl)methane 73
23.2.2.1.4 Method 4: Lithiation of (Trialkylsilyl)ketenes and Trapping with
Chlorosilanes 74
23.2.2.1.5 Method 5: Synthesis of Bis(silyl)ketenes from Other Bis(silyl)ketenes
via Potassium 2 Silylacetylen 1 olates 74
23.2.3 Product Subclass 3: (Aryl) and (Alkyl)silylketenes 76
23.2.3.1 Synthesis of Product Subclass 3 76
23.2.3.1.1 Methodi: 1,3 Silyl Shift of 1 (Siloxy)alk 1 ynes 76
23.2.3.1.2 Method 2: Wolff Rearrangement of a Diazo a silyl Ketones 77
23J.3.1.2.1 Variation 1: By Thermolysis 77
23J.3.1.2.2 Variation 2: By Photolysis 77
23.2.3.1.2.3 Variation 3: By Metal Catalysis 78
23.2.3.2 Applications of Product Subclass 3 in Organic Synthesis 79
23JJ.2.1 Methodi: [2 + 2] Cycloadditions Leading to p Lactones 79
Table of Contents XI
23.2.3.2.2 Method2: [4 + 1] Annulation Leading to 1,3 Dihydro 2H inden 2 ones ••• 80
23.2.4 Product Subclass 4: Silyl(vinyl)ketenes 84
23.2.4.1 Synthesis of Product Subclass 4 84
23.2.4.1.1 Method 1: Dehydrohalogenationof a Silyl a,P unsaturated Acid Chlorides 84
23.2.4.1.2 Method 2: Wolff Rearrangement of a Diazo a silyl a'.P' Unsaturated
Ketones 85
23.2.4.1.3 Method 3: Electrocyclic Ring Opening of 2 Silylcyclobut 2 enones 86
23.2.4.1.4 Method 4: Reaction of Bis(silyl)acetylenes with Chromium Carbene
Complexes 87
23.2.4.2 Applications of Product Subclass 4 in Organic Synthesis 88
23.2.4.2.1 Method 1: Formation of Cyclohexenones and Phenols by
[4 + 2]Cycloadditions 88
23.2.4.2.2 Method 2: Formation of 5,6 Dihydro 2H pyran 2 ones and
5,6 Dihydropyridin 2(1H) ones by [4 + 2] Cycloadditions 89
23.2.4.2.3 Method 3: Formation of Cyclopent 2 en 1 ones by [4+1] Annulation — 91
23.2.5 Product Subclass 5: Miscellaneous Silylketenes 96
23.2.5.1 Synthesis of Product Subclass 5 96
23.2.5.1.1 Method 1: Synthesis of Bromo(trialkylsilyl)ketenes by
Dehydrohalogenation 96
23.2.5.1.2 Method 2: Synthesis of Alkoxy(triarylsilyl)ketenes from Pentacarbonyl
Complexes 96
23.2.5.1.3 Methods 3: Miscellaneous Reactions 96
233 Product Class 3: Halogen Substituted Ketenes
T. T. Tidwell
233 Product Class 3: Halogen Substituted Ketenes 101
23J.i Product Subclass 1: Fluoro and Difluoroketenes 104
233.1.1 Synthesis of Product Subclass 1 105
233.1.1.1 Method 1: Fluoroketene by Pyrolysis of Fluoroacetic Anhydride 105
233.1.1.2 Method 2: Fluoroketene by Dehydrochlorination of Fluoroacetyl Chloride 105
233.1.1.3 Method 3: Difluoroketene from 1,1,2 Trifluoro 2 (trifluoromethoxy)
ethene 107
233.1.1.4 Method 4: Difluoroketene by Photolysis of Perfluorocyclobutanone 107
233.1.1.5 Method 5: Difluoroketene by Dehalogenation of Bromo(difluoro)acetyl
Chloride with Zinc 108
233.1.1.6 Method 6: Acyl(fluoro)ketenes by Thermolysis of a Fluorodioxinones ••• 108
233.1.1.7 Method 7: Fluoro(pentafluoroethyl)ketene by Fluoride Induced
Dephosphorylation 109
233.1.1.8 Method 8: Difluoroketene by Photoisomerization/Oxygenation of
Difluoroacetylene 110
233.1.1.9 Method 9: Fluoro(1,2,3,4,4 pentafluorobuta 1,3 dienyl)ketenefrom
Perfluorocyclohexa 2,4 dienone 110
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 111
XII Table of Contents
233.1.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloaddition of Fluoroketenes
with Alkenes 111
233.1.2.2 Method 2: P Lactams by [2 + 2] Cycloaddition of Fluoroketenes with
Imines 113
233.2 Product Class 2: Chloro and Dichloroketenes 113
233.2.1 Synthesis of Product Subclass 2 114
233.2.1.1 Method 1: Alkyl(chloro)ketenes by Dehydration of Carboxylic Acids 115
233.2.1.2 Method 2: Chloroketenes by Dehydrochlorination of Chloroalkanoyl
Halides 116
233.2.1.2.1 Variation 1: Chloroketene by Pyrolytic Dehydrochlorination of
Chloroacetyl Chloride 118
233.2.1.2.2 Variation 2: Substituted Choroketenes by Dehydrochlorination of
2 Chloroacyl Chlorides 119
233.2.1.3 Method 3: Dichloroketene by Photolysis of a Cyclic Carbonate 119
233.2.1.4 Method 4: Dichloroketene by Dehalogenation of Trichloroacetyl Halides
with Zinc 119
233.2.1.4.1 Variation 1: Chloroketenes by Dechlorination of 2 Chloroacyl Chlorides
with Diphenyl(trimethylsilyl)phosphine 124
233.2.1.5 Method 5: Chloro(cyano)ketene by Thermolysis of
4 Azido 3 chloro 5 methoxyfuran 2(5H) one 125
233.2.2 Applications of Product Subclass 2 in Organic Synthesis 126
233.2.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloadditions of Choroketenes
with Alkenes and Dienes 126
233.2.2.2 Method 2: Methylenecyclobutanones by [2 + 2] Cycloaddition of
Chloroketenes with Allenes 137
233.2.2.3 Method 3: Cyclobutenones by [2 + 2] Cycloaddition of Chloroketenes
with Alkynes 138
233.2.2.4 Method 4: P Lactams by [2 + 2] Cycloaddition of Chloroketenes with
Imines 140
233.2.2.4.1 Variation 1: P and 5 Lactams by [2 + 2] and [4 + 2] Cycloaddition
Reactions of Chloroketenes with Vinylic Imines 141
233.2.2.4.2 Variation 2: Y"Lactams ar|d yLactones by [3 + 2] Cycloaddition of
Dichloroketene with N Vinylsulfimides 143
233.2.2.5 Method 5: P Lactones by [2 + 2] Cycloaddition of Chloroketenes with
Carbonyl Compounds 146
233.2.2.6 Method 6: y Lactones from Dichloroketene with Vinyl Sulfoxides 148
233.2.2.6.1 Variation 1: y Lactones from Dichloroketene with Chiral Vinyl Sulfoxides • 149
233.2.2.7 Method 7: Thioesters by Ketene Claisen Reaction of Dichloroketene
with Allyl Sulfides 150
233.2.2.8 Method 8: A Macrocyclic Lactone by the Ketene Claisen Reaction of
Dichloroketene with a Vinyltetrahydropyran 151
233.2.2.9 Method 9: y Lactones and Lactams by the Reactions of Dichloroketene
with Three Membered Heterocycles 152
233.2.2.9.1 Variation 1: A Lactam by the Reaction of Dichloroketene with a
Vinylaziridine 153
Table of Contents XIII
233.2.2.9.2 Variation 2: Ketene Acetals from Cycloaddition of Chloro(cyano)ketene
with 2 Phenyloxirane 154
233.3 Product Subclass 3: Bromo and lodoketenes 154
233.3.1 Synthesis of Product Subclass 3 154
233.3.1.1 Method 1: Bromo and lodoketenes by Dehydrochlorination of
Haloacetyl Chlorides 154
233.3.1.1.1 Variation 1: Bromoketene by Dehydrochlorination of Bromoacetyl
Chloride with a Strong Stoichiometric Base and a Shuttle Base 156
233.3.1.2 Method 2: Bromoketene by Pyrolysis of 2 Bromocyclobutanone 157
233.3.1.3 Method 3: Bromoketenes by Dehalogenation of Haloacyl Halides 157
233.3.1.3.1 Variation 1: Dibromoketene by Triphenylphosphine lnduced Elimination
from Trimethylsilyl Tribromoacetate 158
233.3.1.4 Method 4: An Aryl(bromo)ketene from a 3 Aryloxirane 2,2 dicarbonitrile 158
233.3.2 Applications of Product Subclass 3 in Organic Synthesis 159
233.3.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloaddition of Bromoketenes
with Alkenes or Dienes 159
233.3.2.1.1 Variation 1: Cyclohex 2 en 1 ones by [4 + 2] Cycloaddition of
Bromo(vinyl)ketenes with Enamines 160
233.3.2.2 Method 2: |3 and 8 Lactams by Cycloaddition of Bromoketenes with
Imines 161
233.3.2.3 Method 3: [3 + 2] Cycloaddition of Aryl(bromo)ketenes with
Pyridiniumolate Betaines 161
233.3.2.4 Method 4: Chiral Aryl(halo)acetates by Stereoselective Addition of Chiral
Alcohols to Bromo and lodoketenes 162
233.3.2.5 Method 5: A Chiral Bromo(chloro)acetate by Stereoselective
Chlorination of Bromoketene 163
233.3.2.6 Method 6: Mixed Dimerization of Bromo(tert butyl)ketenes with
tert Butylketene 163
23.4 Product Class 4: Oxygen Substituted Ketenes
C. Palomo, M. Oiarbide, and J. M. Aizpurua
23.4 Product Class 4: Oxygen Substituted Ketenes 169
23.4.1 Synthesis of Product Class 4 170
23.4.1.1 Method 1: Elimination Reactions of Carboxylic Acids or Their Derivatives 170
23.4.1.1.1 Variation 1: Dehydration of Carboxylic Acids by Activating Reagents 170
23.4.1.1.2 Variation 2: Dehydrohalogenation of Carboxylic Acid Chlorides with
Tertiary Amines in Solution 172
23.4.1.1.3 Variation 3: Dehydrohalogenation of Carboxylic Acid Chlorides with
Solid Supported Bases 174
23.4.1.2 Method 2: Photolysis of Metal Carbene Complexes 177
23.4.1.3 Method 3: Dirhodium Tetraacetate Catalyzed Decomposition of a Diazo
Anhydrides 179
23.4.1.4 Methods 4: Miscellaneous Methods 181
23.4.2 Applications of Product Class 4 in Organic Synthesis 181
XIV Table of Contents
23.4.21 Method 1: [2 + 2] Cycloaddition Reactions Leading to Cyclobutanones,
P Lactones, and (3 Lactams 181
23.4.2.1.1 Variation 1: With Alkenes, Enol Ethers, or Enecarbamates 181
23.4.2.1.2 Variation 2: With Aldehydes or Ketones 187
23.4.2.1.3 Variation 3: With Imines 189
23.4.2.2 Method 2: Lewis Acid Catalyzed [3,3] Sigmatropic Bellus Claisen
Rearrangements 194
23.5 Product Class 5: Sulfur and Selenium Substituted Ketenes
C. Palomo, J. M. Aizpurua, I. Canboa, and E. Gomez Bengoa
23.5 Product Class 5: Sulfur and Selenium Substituted Ketenes 199
23.5.1 Product Subclass 1: Sulfur Substituted Ketenes 199
23.5.1.1 Synthesis of Product Subclass 1 200
233.1.1.1 Method 1: Elimination Reactions of Carboxylic Acids and Their
Derivatives 200
233.1.1.1.1 Variation 1: Dehydration of Carboxylic Acids 200
233.1.1.1.2 Variation 2: Dehydrohalogenation of Acyl Halides 201
233.1.1.2 Method 2: Wolff Rearrangement of Diazo Compounds 203
233.1.1.2.1 Variation 1: Photochemical Wolff Rearrangement 203
233.1.1.2.2 Variation 2: Thermal Wolff Rearrangement 204
233.1.1.2.3 Variation 3: Metal Catalyzed Wolff Rearrangement 205
233.1.1.3 Method 3: Photolysis of Metal Carbene Complexes 205
233.1.1.4 Method 4: Fragmentation of Cyclobutene 1,2 diones 206
233.1.1.5 Methods 5: Miscellaneous Preparations 207
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 208
233.1.2.1 Methodi: [2+ 2] Cycloaddition Reactions 208
233.1.2.1.1 Variation 1: Reaction with Alkenes and Alkynes Leading to
Cyclobutanones and Cyclobutenones 208
233.1.2.1.2 Variation 2: Reaction with Imines Leading to P Lactams 212
233.1.2.2 Method 2: Formation of Allenes by Wittig Alkenation 214
233.2 Product Subclass 2: Selenium Substituted Ketenes 215
233.2.1 Synthesis of Product Subclass 2 215
233.2.1.1 Methodi: Dehydrohalogenation of Acyl Chlorides 215
233.2.1.2 Method 2: Reactions of Silver Ketenide 217
233.2.2 Applications of Product Subclass 2 in Organic Synthesis 217
233.2.2.1 Methodi: [2+ 2] Cycloaddition Reactions Leading to P Lactams 217
23.6 Product Class 6: Nitrogen and Phosphorus Substituted Ketenes
C. Palomo and J. M. Aizpurua
23.6 Product Class 6: Nitrogen and Phosphorus Substituted Ketenes 221
23.6.1 Product Subclass 1: Nitrogen Substituted Ketenes 221
23A1.1 Synthesis of Product Subclass 1 222
Table of Contents XV
23.6.1.1.1 Method 1: Elimination Reactions of a Amino Acids or Their Derivatives • 222
23.6.1.1.2 Method 2: Photolysis of Metal Carbene Complexes 224
23.6.1.2 Applications of Product Subclass 1 in Organic Synthesis 227
23.6.1.2.1 Method 1: Addition of Nitrogen or Oxygen Nucleophiles 227
23.6.1.2.2 Method 2: Cycloaddition Reactions with Alkenes Leading to
Cyclobutanones 229
23.6.1.2.3 Method 3: Cycloaddition Reactions with Imines or Hydrazones Leading
to P Lactams 230
23.6.1.2.4 Method 4: Lewis Acid Catalyzed Bellus Claisen Rearrangement 233
23.6.2 Product Subclass 2: Phosphorus Substituted Ketenes 234
23.6.2.1 Synthesis of Product Subclass 2 235
23.6.2.1.1 Method 1: Elimination Reactions of a Phosphorylcarboxylic Acid
Derivatives 235
23.6.2.1.2 Method 2: Wolff Rearrangement of ct Diazo P oxophosphonates 238
23.6.2.1.3 Method 3: Dehydroalkoxylation of ct Triarylphosphoranylidene Esters ¦•• 239
23.6.2.1.4 Method 4: Thermolysis of Phosphinoethynyl Ethers 240
23.7 Product Class 7: Alkylideneketenes
W. F. Austin, J. J. Kowalczyk, C. B. Dudley, and R. L. Danheiser
23.7 Product Class 7: Alkylideneketenes 245
23.7.1 Product Subclass 1: Substituted Methyleneketenes 245
23.7.1.1 Synthesis of Product Subclass 1 245
23.7.1.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 245
23.7.1.1.2 Method 2: Cycloreversion Reactions 246
23.7.1.1.3 Method 3: Thermolysis of Alkylidene Derivatives of Meldrum's Acid 247
23.7.1.1.4 Method 4: Dehalogenation of 2 Bromoacryloyl Chlorides 248
23.7.1.1.5 Method 5: Alkenation of Carbonyl Compounds with
Phosphorylideneketenes 248
23.7.1.2 Applications of Product Subclass 1 in Organic Synthesis 249
23.7.1.2.1 Method 1: [2+2] Cycloadditions Leading to Cyclobutane 1,3 diones
or a Alkylidene Substituted P Lactones 249
23.7.1.2.2 Method 2: Generation of Vinylidenes by Thermolysis or Photolysis 251
23.7.1.2.3 Method 3: Rearrangements Triggering Cyclization Reactions 252
23.7.2 Product Subclass 2: Carbon Suboxide 253
23.7.2.1 Synthesis of Product Subclass 2 253
23.7.2.1.1 Method 1: Elimination from Malonic Acid Derivatives 253
23.7.2.1.2 Method 2: Thermolysis of O,O Diacetyltartaric Anhydride 254
23.7.2.1.3 Method 3: Dehalogenation of Dibromomalonyl Chloride 254
23.7.2.2 Applications of Product Subclass 2 in Organic Synthesis 255
23.7.2.2.1 Method 1: Reaction with Nucleophiles Leading to Malonic Acid
Derivatives 255
23.7.2.2.2 Method 2: Generation of Oxovinylidene by Photolysis 256
XVI Table of Contents
23.8 Product Class 8: Cyanoketenes
H. W. Moore
23.8 Product Class 8: Cyanoketenes 259
23.8.1 Synthesis of Product Class 8 259
23.8.1.1 Method 1: Synthesis from 3 Azidocyclobut 3 ene 1,2 diones 260
23.8.1.2 Method 2: Synthesis from 2,5 and 2,6 Diazidobenzo 1,4 quinones 261
23.8.1.3 Method 3: Synthesis from 4 Azido 3 halo 5 methoxyfuran 2(5H) ones • • 263
23.8.1.4 Method 4: Synthesis of Cyano(trimethylsiloxy)ketene via a
Retro Diels Alder Reaction 266
23.8.1.5 Method 5: Synthesis of the Parent Cyanoketene 267
23.9 Product Class 9: Acylketenes
G. Kollenz and S. Ebner
23.9 Product Class 9: Acylketenes 271
23.9.1 Product Subclass 1: Monoalkanoylketenes and Formylketenes 272
23.9.1.1 Synthesis of Product Subclass 1 272
233.1.1.1 Method 1: Ruthenium(VIII) Oxide Oxidation of an Acylallene 272
23.9.1.1.2 Method 2: Dehydrochlorination of Acid Chlorides 272
23.9.1.1.3 Method 3: Flash Vacuum Pyrolysis 273
23.9.1.1.3.1 Variation 1: Of P Oxo Esters 273
23.9.1.1.3.2 Variation 2: Of 4H 1,3 Dioxin 4 onesand a 4H 1,3 Oxazin 4 one 273
233.1.1.3.3 Variation 3: Of Furan 2,3 diones 275
23.9.1.1.4 Method 4: Thermolysis Reactions 276
23.9.1.1.4.1 Variation 1: Of P Oxo Esters 276
233.1.1.4.2 Variation2: Of4H 1,3 Dioxin 4 ones 276
233.1.1.4.3 Variation 3: Of 5 Acyl 2,2 dimethyl 1,3 dioxane 4,6 diones 280
233.1.1.4.4 Variation 4: Of 4 Ethoxybut 3 yn 2 one 281
233.1.1.4.5 Variation 5: Of 2 Diazo 1,3 dicarbonyl Compounds 281
233.1.1.5 Method5: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 281
233.1.1.6 Method 6: [4 + 2] Dimerization of Dipivaloylketene 282
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 283
233.1.2.1 Method 1: Cycloaddition Reactions 283
23.9.1.2.2 Method 2: Addition of Nucleophiles 284
233.2 Product Subclass 2: a (Oxomethylene)cycloalkanones 285
233.2.1 Synthesis of Product Subclass 2 285
23.9.2.1.1 Method 1: Dehydrochlorination of Acid Chlorides 285
233.2.1.2 Method 2: Flash Vacuum Pyrolysis of Cyclic P Oxo Esters 286
233.2.1.3 Method 3: Thermolysis Reactions 286
233.2.1.3.1 Variation 1: Of a Fused 4H 1,3 Dioxin 4 one 287
233.2.1.3.2 Variation 2: Of Cyclic 2 Diazo 1,3 diketones 288
233.2.1.4 Method 4: Photolysis of Cyclic 2 Diazo 1,3 diketones 290
Table of Contents XVII
233.3 Product Subclass 3: a (Oxomethylene)cycloalkenones 291
23.9.3.1 Synthesis of Product Subclass 3 291
23.9.3.1.1 Method 1: Thermolysis Reactions 291
23.9.3.1.1.1 Variation 1: Of Salicylic Acid Derivatives 291
23.9.3.U.2 Variation 2: Of Fused Furan 2,3 diones 292
23.9.3.1.1.3 Variation 3: Of 2 Diazo 1H indene 1,3(2H) dione 293
23.9.3.1.2 Method 2: Photolysis Reactions 293
23.9.3.1.2.1 Variation 1: Of 2 Phenyl 4H 1,3 benzodioxin 4 one 293
23.9.3.1.2.2 Variation 2: Of 2,3 Benzodioxin 1,4 dione 293
23.9.3.1.2.3 Variation 3: Of Fused 2 Diazo 1,3 diketones 294
23.9.3.1.3 Method 3: Addition of Alkynes to Carbon Suboxide 295
23.9.4 Product Subclass 4: a (Oxomethylene)heterocycloalkanones 296
23.9.4.1 Synthesis of Product Subclass 4 296
23.9.4.1.1 Methodi: Thermolysis of a Furo[3,4 d] 1,3 dioxinone 296
23.9.4.1.2 Method 2: Photolysis Reactions 297
23.9.4.1.2.1 Variation 1: Of 5 Diazo 2,2 dimethyl 1,3 dioxane 4,6 dione 297
23.9.4.1.2.2 Variation 2: Of 3 Diazo 1 methylquinoline 2,4(1H,3H) dione 298
23.9.5 Product Subclass 5: Dialkanoylketenes 299
233.5.1 Synthesis of Product Subclass 5 299
23.9.5.1.1 Method 1: Flash Vacuum Pyrolysisof 5 tert Butyl 4 pivaloylfuran 2,3
dione 299
233.5.2 Applications of Product Subclass 5 in Organic Synthesis 300
233.5.2.1 Methodi: Cycloaddition Reactions 300
233.5.2.2 Method 2: Addition of Nudeophiles 301
233.6 Product Subclass 6: Monoaroylketenes 302
233.6.1 Synthesis of Product Subclass 6 302
233.6.1.1 Methodi: Thermolysis Reactions 302
233.6.1.1.1 Variation 1: Of P Oxo Esters 302
233.6.1.1.2 Variation2: Of 4H 1,3 Dioxin 4 ones and 1,3 Dioxane 4,6 diones 302
233.6.1.1.3 Variation 3: Of Furan 2,3 diones 303
233.6.1.1.4 Variation 4: Of 2 Diazo 1,3 diketones 305
23.9.6.1.2 Method 2: Photolysis Reactions 310
23.9.6.1.2.1 Variation 1: Of 5 Phenylfuran 2,3 dione 310
23.9.6.1.2.2 Variation 2: Of 2 Diazo 1,3 diketones 310
233.6.1.2.3 Variation 3: Of a Mesoionic Compound 311
233.7 Product Subclass 7: Diaroylketenes 311
233.7.1 Synthesis of Product Subclass 7 311
233.7.1.1 Methodi: Flash Vacuum Pyrolysis of 4 Benzoyl 5 phenylfuran 2,3 dione 311
23.9.7.1.2 Method 2: Thermolysis of 4 Benzoyl 5 phenylfuran 2,3 dione 312
233.8 Product Subclass 8: Carboxyketenes 314
233.8.1 Synthesis of Product Subclass 8 314
XVIII Table of Contents
23.9.8.1.1 Method 1: Flash Vacuum Pyrolysis of 5 Alkylidene 2,2 dimethyl 1,3
dioxane 4,6 diones 314
23.9.9 Product Subclass 9: (Alkoxycarbonyl)ketenes 315
23.9.9.1 Synthesis of Product Subclass 9 315
23.9.9.1.1 Method 1: Dehydrochlorination of Acid Chlorides 315
23.9.9.1.2 Method 2: Thermolysis Reactions 316
23.9.9.1.2.1 Variation 1: Of Acid Derivatives 316
23.9.9.1.2.2 Variation 2: Of 6 Methoxy 4H 1,3 dioxin 4 ones 317
23.9.9.1.2.3 Variation 3: Of a Pyrro!o[1,2 o]quinoxalinetrione 317
23.9.9.1.2.4 Variation 4: Of Dimethyl Diazomalonate 317
23.9.9.1.3 Method 3: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 318
23.9.9.2 Applications of Product Subclass 9 in Organic Synthesis 318
23.9.9.2.1 Method 1: Cycloaddition Reactions 318
23.9.9.2.2 Method 2: Addition of Nucleophiles 319
233.10 Product Subclass 10: Acyl(alkoxycarbonyl)ketenes 319
23.9.10.1 Synthesis of Product Subclass 10 319
23.9.10.1.1 Method 1: Flash Vacuum Pyrolysis of Methyl 2 rert Butyl 4,5 dioxo 4,5
dihydrofuran 3 carboxylate 319
23.9.10.1.2 Method 2: Thermolysis Reactions 320
23.9.10.1.2.1 Variations Of4H 1,3 Dioxin 4 ones 320
233.10.1.2.2 Variation 2: Of Ethyl 4,5 Dioxo 2 phenyl 4,5 dihydrofuran 3 carboxylate ¦ 321
233.10.2 Applications of Product Subclass 10 in Organic Synthesis 322
23.9.10.2.1 Method 1: Cycloaddition Reactions 322
233.10.2.2 Method 2: Addition of Amines 323
233.11 Product Subclass 11: Bis(alkoxycarbonyl)ketenes 324
233.11.1 Synthesis of Product Subclass 11 324
233.11.1.1 Method 1: Thermolysis of 2 Diazo 3 oxosuccinates 324
233.11.1.2 Method 2: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 324
233.11.1.3 Method 3: Reaction of Tetraethoxyallene with Phosgene 325
233.11.2 Applications of Product Subclass 11 in Organic Synthesis 325
233.11.2.1 Method 1: Preparation of Allenetetracarboxylates 325
23.9.11.2.2 Method 2: Cycloaddition Reactions 326
233.11.2.3 Method 3: Ring Transformations of Five Membered Heterocycles 326
233.12 Product Subclass 12: (Chlorocarbonyl)ketenes 327
233.12.1 Synthesis of Product Subclass 12 327
233.12.1.1 Method 1: Dehydrochlorination of Malonyl Chlorides 327
233.12.2 Applications of Product Subclass 12 in Organic Synthesis 329
233.12.2.1 Method 1: Cycloaddition Reactions 329
233.12.2.2 Method 2: Condensation Reactions 330
233.13 Product Subclass 13: Fluorinated Acylketenes 333
233.13.1 Synthesis of Product Subclass 13 333
Table of Contents XIX
23.9.13.1.1 Method 1: Thermolysis Reactions 333
23.9.13.1.1.1 Variation 1: Of (Trifluoromethyl)malonic Acid Derivatives 333
23.9.13.1.1.2 Variation 2: Of Fluorinated 4H 1,3 Dioxin 4 ones 334
23.9.13.1.2 Method 2: Transformation of Fluorinated Alkenes and Alkynes 335
23.9.13.1.2.1 Variation 1: By Reaction with Sulfur Trioxide 335
23.9.13.1.2.2 Variation 2: With Lewis Acid Catalysis 336
23.9.13.1.3 Method 3: Photolysis of Methyl 2 Diazo 4,4,4 trifluoroacetoacetate — 337
23.9.13.2 Applications of Product Subclass 13 in Organic Synthesis 337
23.9.13.2.1 Method 1: Cycloaddition Reactions 337
23.9.13.2.2 Method 2: Electrophilic Substitution Reactions 338
23.9.13.2.3 Method 3: Addition of Nucleophiles 339
233.14 Product Subclass 14: Acyl(phosphoryl)ketenes and
Acyl(trialkylmetal)ketenes 341
23.9.14.1 Synthesis of Product Subclass 14 341
23.9.14.1.1 Method 1: Transformation of [Dialkoxy(bromo)phosphoranylidene]malo
nates 341
23.9.14.1.2 Method 2: Photolysis or Thermolysis of Methyl 2 Diazo 3 (diisoprop
oxyphosphoryl) 3 oxopropanoate 341
23.9.14.1.3 Method 3: Addition of Organometallic Compounds to Carbon Suboxide 341
23.9.14.1.4 Method 4: Transformation of Functionalized Ethoxyacetylenes 342
23.10 Product Class 10: Imidoylketenes
C. Kollenz
23.10 Product Class 10: Imidoylketenes 351
23.10.1 Product Subclass 1: N Unsubstituted and N Alkyl Substituted
Imidoylketenes 351
23.10.1.1 Synthesis of Product Subclass 1 351
23.10.1.1.1 Method 1: Pyrolysis Reactions 352
23.10.1.1.1.1 Variation 1: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 352
23.10.1.1.1.2 Variation 2: Flash Vacuum Pyrolysis of Pyrrole 2,3 diones 353
23.10.1.1.1.3 Variation 3: Thermolysis of 3 Aminoacrylates 353
23.10.1.1.2 Method 2: Reaction of 1 Aminopyridinium Iodide with
2,3 Diphenylcycloprop 2 en 1 one 354
23.10.1.1.3 Method 3: Extrusion of Sulfur from lsothiazol 5(2H) ones 355
23.10.2 Product Subclass 2: (At Acylimidoyl)ketenes 356
23.10.2.1 Synthesis of Product Subclass 2 356
23.10.2.1.1 Method 1: Pyrolysis of 3 (Acylamino)acrylates 356
23.10.2.1.2 Method 2: Reaction of Pyridinium Ylides with
2,3 Diphenylcycloprop 2 en 1 one 357
23.10.2.1.3 Method 3: Reaction of Di tert butoxyacetylene with Benzoyl Isocyanate • 357
23.103 Product Subclass 3: (W Arylimidoyl)ketenes 358
23.io.3i Synthesis of Product Subclass 3 358
23.10.3/u Method 1: Thermolysis Reactions 359
XX Table of Contents
23.10.3.1.1.1 Variation 1: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 359
23.10.3.1.1.2 Variation 2: Pyrolysis of 1 Aryl 1H pyrrole 2,3 diones 360
23.10.3.1.1.3 Variation 3: Flash Vacuum Pyrolysis of 1 Aryl 1H 1,2,3 triazoles 362
23.10.3.1.1.4 Variation 4: Thermolysis of N Arylketenimines 363
23.10.3.1.1.5 Variation 5: Thermolysis of Mesoionic Compounds 364
23.10.3.1.2 Method 2: Extrusion of Sulfur from lsothiazol 5(2H) ones 364
23.10.4 Product Subclass 4: A/Hetaryl Substituted Imidoylketenes 365
23.10.4.1 Synthesis of Product Subclass 4 365
23.10.4.1.1 Method 1: Pyrolysis Reactions 365
23.10.4.1.1.1 Variation 1: Flash Vacuum Pyrolysis of 1 (1H Pyrazol 5 yl) 1H 1,2,3
triazoles 365
23.10.4.1.1.2 Variation 2: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 366
23.10.4.1.2 Method 2: Lithiation of lsoxazol 5(2H) ones 366
23.10.5 Product Subclass 5: Acyl(imidoyl)ketenes 367
23.10.5.1 Synthesis of Product Subclass 5 367
23.10.5.1.1 Method 1: Thermolysis Reactions of Pyrrole 2,3 diones and
Furan 2,3 diones 367
23.10.5.1.1.1 Variation 1: In the Solid State 367
23.10.5.1.1.2 Variation 2: In Solution 368
23.10.6 Product Subclass 6: N Unsubstituted 6 (0xomethylene)cyclohexa
2.4 dien l imines 372
23.10.6.1 Synthesis of Product Subclass 6 372
23.10.6.1.1 Method 1: Thermolysis of 1,2,3 Benzotriazin 4(3H) ones 372
23.10.6.1.2 Method2: Reactions of 3,2,1 Benzoxathiazin 4(1 H) one 2 Oxide 373
23.10.7 Product Subclass 7: N Substituted 6 (0xomethylene)cyclohexa
2,4 dien 1 imines 374
23.10.7.1 Synthesis of Product Subclass 7 374
23.10.7.1.1 Method 1: Photolysis Reactions of 1,2,3 Benzotriazin 4(3H) ones 375
23.10.7.1.2 Method 2: Thermolysis Reactions 376
23.10.7.1.2.1 Variation 1: Of a 3,2,1 Benzoxathiazin 4(1H) one 2 Oxide 376
23.10.7.1.2.2 Variation2: Of2,1 Benzisothiazol 3(1H) ones 377
23.10.7.1.2.3 Variation 3: Of 1 Phenyl 1H indole 2,3 dione 377
23.10.7.1.3 Method 3: Ring Opening of 2,1 Benzisoxazol 1 ium Salts 377
23.11 Product Class 11: Alk 1 ynylketenes
H. W. Moore
23.11 Product Class 11: Alk 1 ynylketenes 381
23.11.1 Synthesis of Product Class 11 381
23.11.1.1 Method 1: Retro Diels Alder Reactions 381
23.11.1.2 Method 2: Thermolysis of 1 Alkoxyalk 1 ynes 384
23.11.1.3 Method 3: Alk 1 ynyl(cyano)ketenes from 2,5 Di(alk 1 ynyl) 3,6
diazidobenzo 1.4 quinones 385
23.11.1.4 Methods 4: Additional Methods for the Generation of Alk 1 ynylketenes • 389
Table of Contents XXI
23.12 Product Class 12: Aryl and Hetarylketenes
T. T. Tidwell
23.12 Product Class 12: Aryl and Hetarylketenes 391
23.12.1 Product Subclass 1: Monoarylketenes 392
23.12.11 Synthesis of Product Subclass 1 393
23.12.1.1.1 Method 1: Monoarylketenes by Dehydration of Arylacetic Acids 393
23.12.1.1.2 Method 2: Monoarylketenes from Arylacetic Anhydrides 393
23.12.1.1.2.1 Variation 1: Arylketene by Decarboxylation of Arylmalonic Acids 394
23.12.1.1.3 Method 3: Monoarylketenes from Arylacetate Esters 394
23.12.1.1.4 Method 4: Monoarylketenes by Dehydrohalogenation of Arylacetyl
Chlorides 395
23.12.1.1.4.1 Variation 1: Monoarylketenes by Dehydrochlorination Using a Shuttle
Procedure with a Kinetic Base and a Stoichiometric Base 396
23.12.1.1.5 Method 5: Monoarylketenes by Dehalogenation of Arylhaloacetyl Halides 399
23.12.1.1.6 Method 6: Monoarylketenes by Wolff Rearrangement of a Diazo Ketones 400
23.12.1.1.6.1 Variation 1: Metal Catalyzed Wolff Rearrangement 401
23.12.1.1.6.2 Variation 2: Monoarylketenes by Microwave and Ultrasound Enhanced
Wolff Rearrangement 403
23.12.1.1.6.3 Variation 3: Monoarylketenes by Photochemical Wolff Rearrangement ••• 404
23.12.1.1.6.4 Variation 4: Phenylketene by Wolff Type Rearrangement of a Sulfur Ylide 405
23.12.1.1.7 Method 7: Monoarylketenes from Ynols and Ynolates 405
23.12.1.1.8 Method 8: Monoarylketenes by Oxidation of Arylacetylenes 406
23.12.1.1.8.1 Variation 1: Monoarylketenes by Oxidation of Lithium Arylacetylides 407
23.12.1.1.8.2 Variation 2: Monoarylketenes by Ruthenium Catalyzed Alkyne
Oxygenation 408
23.12.1.1.9 Method 9: Monoarylketenes from Metal Carbene Complexes 409
23.12.1.2 Applications of Product Subclass 1 in Organic Synthesis 410
23.12.1.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to
Monoarylketenes 410
23.12.1.2.2 Method 2: Ketones and Vinyl Ethers by Addition of Carbon Electrophiles 410
23.12.1.2.3 Method 3: /V Aroyloxyamines by Aminoxyl Radical Addition to
Monoarylketenes 411
23.12.1.2.4 Method 4: Cyclobutanones by [2+2] Cycloaddition with Alkenes and
Dienes 412
23.12.1.2.5 Method 5: Cyclobutenones by [2 + 2] Cycloaddition of Monoarylketenes
with Alkynes 414
23.12.1.2.6 Method 6: p" Lactams by [2 + 2] Cycloaddition of Monoarylketenes with
Imines 416
23.12.1.2.6.1 Variation 1: Pyrimidinones by [4+2] Cycloaddition of Monoarylketenes
with 1,3 Diazabuta 1,3 dienes 418
23.12.1.2.7 Method 7: 2 Arylacetate Derivatives by [4 + 2] Cycloaddition of
o Chloranil with Ketene Enolates 419
23.12.1.2.8 Method 8: Carbene Formation by Decarbonylation of Monoarylketenes • 419
23.12.2 Product Subclass 2: Alkyl(aryl) and Aryl(vlnyl)ketenes 420
23.12.2.1 Synthesis of Product Subclass 2 421
XXII Table of Contents
23.12.2.1.1 Method 1: Alkyl(aryl)ketenes by Elimination from 2 Arylalkanoate Esters 421
23.12.2.1.2 Method 2: Alkyl(aryl)ketenes by Dehydrohalogenation of 2 Arylalkanoyl
Chlorides 423
23.12.2.1.3 Method 3: Alkyl(aryl)ketenes by Dehalogenation of
2 Aryl 2 haloalkanoyl Halides 423
23.12.2.1.4 Method 4: Alkyl(aryl)ketenes by Wolff Rearrangement of a Diazo
Ketones 424
23.12.2.1.5 Method 5: Alkyl(aryl)ketenes by Decarboxylation of Malonic Acids 425
23.12.2.1.6 Method 6: Aryl(vinyl)ketenes by Cyclobutenone Ring Opening 425
23.12.2.1.7 Method 7: Aryl(vinyl)ketenes from Metal Carbene Complexes 426
23.12.2.1.8 Method 8: Alkyl(aryl)ketenes by [4+2] Cycloadditions of Cyclic Diazines 427
23.12.2.2 Applications of Product Subclass 2 in Organic Synthesis 428
23.12.2.2.1 Method 1: 2 Arylalkanoic Acid Derivatives by Stereoselective
Esterification of Alkyl(aryl)ketenes 428
23.12.2.2.1.1 Variation 1: Chiral 2 Arylalkanoate Esters by Catalytic Stereoselective
Addition of Methanol to Alkyl(aryl)ketenes 431
23.12.2.2.1.2 Variation 2: Chiral 2 Arylalkanoate Enol Esters by Catalytic Stereoselective
Esterification of Alkyl(aryl)ketenes with Aldehydes 433
23.12.2.2.1.3 Variation 3: Chiral 2 Arylalkanamides by Stereoselective Amination of
Alkyl(aryl)ketenes 434
23.12.2.2.2 Method 2: Ketones and Vinyl Esters and Ethers by Addition of Carbon
Nucleophiles to Ethyl(phenyl)ketene 436
23.12.2.2.3 Method 3: Divinyl Ketone Formation by Iridium Alkyne Complex
Addition to Methyl(phenyl)ketene with Double C—H
Activation 438
23.12.2.2.4 Method 4: Lactones and Cycloalkanones by Electrophilic Addition to
Alkyl(aryl)ketenes 438
23.12.2.2.5 Method 5: Allenyl Ketones and Esters by Wittig Type Reactions of
Alkyl(aryl)ketenes 439
23.12.2.2.6 Method 6: Cyclobutanones by [2 + 2] Cycloaddition of
Methyl(phenyl)ketene with Alkenes and Dienes 440
23.12.2.2.6.1 Variation 1: Cyclobutanones by Intramolecular [2 + 2] Cycloaddition of
Aryl(pent 4 enyl)ketenes 441
23.12.2.2.7 Method 7: Naphthol Formation by Intramolecular Cyclization of an
Alkyl(aryl)ketene with an Alkynyl Group 441
23.12.2.2.8 Method 8: p Lactone Formation by Intramolecular Cycloaddition of an
Alkyl(aryl)ketene with a Carbonyl Group 442
23.12.2.2.9 Method 9: Succinic Anhydrides by Oxidation of Alkyl(aryl)ketenes 442
23.12.2.2.10 Method 10: Aminoxyl Radical Substituted Polymers from Alkyl(aryl)ke
tenes 442
23.12.3 Product Subclass 3: Diarylketenes 443
23.12.3.1 Synthesis of Product Subclass 3 444
23.12.3.1.1 Method 1: Diarylketenes by Dehydration of Diarylacetic Acids 444
23.12.31.2 Method 2: Diarylketenes by Dehydrochlorination of Diarylacetyl
Chlorides 445
23.123.1.3 Method 3: Diarylketenes by Dehalogenation of Diarylhaloacetyl Halides 446
Table of Contents XXIII
23.12.3.1.4 Method 4: Diarylketenes by Pyrolysisof Diarylketene Acetals 448
23.12.3.1.5 Method 5: Diarylketenes by Wolff Rearrangement of ce Diazo Ketones •¦ 448
23.12.3.1.5.1 Variation 1: Diarylketenes by Photochemical Wolff Rearrangement of
a Diazo Ketones 449
23.12.3.1.6 Method 6: Diarylketenes by Oxidation of Diarylacetylenes 449
23.12.3.2 Applications of Product Subclass 3 in Organic Synthesis 450
23.12.3.2.1 Method 1: Diarylacetic Acid Derivatives by Nucleophilic Additions to
Diarylketenes 450
23.12.3.2.2 Method 2: Alcohols, Aldehydes, Ketones, and Enol Derivatives by
Addition of Hydrogen, Carbon, and Silicon Nucleophiles
and Electrophiles to Diarylketenes 450
23.12.3.2.2.1 Variation 1: Cyclopropanones by Diazoalkane Addition to Diarylketenes ¦• 453
23.12.3.2.3 Method 3: Aminoxy Esters from Aminoxyl Radical Addition to
Diarylketenes 454
23.12.3.2.4 Method 4: Allenes by Wittig Reactions 454
23.12.3.2.4.1 Variation 1: Ketenimines by Aza Wittig Reaction of Diarylketenes 455
23.12.3.2.5 Method 5: Cyclobutanones and Other Products by Cycloaddition
Reactions with Alkenes and Dienes 455
23.12.3.2.6 Method 6: [2 + 2] and [2 + 2 + 2] Cycloadditions with Alk 1 ynyl Ethers •¦• 459
23.12.3.2.7 Method 7: p Lactams by [2 + 2] Cycloaddition with Imines 459
23.12.3.2.7.1 Variation 1: S Lactams by [4+2] Cycloaddition with Chiral
2 Vinyl 4,5 dihydrothiazoles 461
23.12.3.2.8 Method 8: P Lactones by [2 + 2] Cycloaddition with Carbonyl Groups— 462
23.12.3.2.8.1 Variation 1: y Lactone Formation by Diarylketene Reaction with Carbonyl
Compounds 463
23.12.3.2.9 Method 9: Polyesters by Oxidation of Diarylketenes 463
23.12.3.2.10 Method 10: Diarylacetylenes by Deoxygenation of Diarylketenes 464
23.12.3.2.11 Method 11: Carbenes and Carbocations by Decarbonylation of
Diarylketenes 464
23.12.4 Product Subclass 4: Fulvenones 465
23.12.4.1 Synthesis of Product Subclass 4 466
23.12.4.1.1 Method 1: Fulvenones by Elimination from Esters 466
23.12.4.1.2 Method 2: Fulvenones by Dehydrochlorination of Acyl Chlorides 466
23.12.4.1.3 Method 3: Fulvenones by Dehalogenation of 2 Haloacyl Halides 467
23.12.4.1.4 Method 4: Fulvenones by Wolff Rearrangement of a Diazo Ketones — 468
23.12.4.1.4.1 Variation 1: Azafulvenones by Wolff Rearrangement and Other Routes • • ¦ 470
23.12.4.1.4.2 Variation 2: Pentafulvenone by Photochemical Wolff like Rearrangement
of 2 Halophenols 471
23.12.4.2 Applications of Product Subclass 4 in Organic Synthesis 472
23.12.4.2.1 Method 1: Pyridinium Zwitterions from Pentafulvenones 472
23.12.4.2.2 Method 2: Cyclobutanones by [2 + 2] Cycloaddition with Alkenes and
Dienes 472
2312.5 Product Subclass 5: Hetarylketenes 473
23.12.5.1 Synthesis of Product Subclass 5 473
23.12.5.1.1 Method 1: Hetarylketenes by Ester Elimination of Hetarylacetates 473
XXIV Table of Contents
23.12.5.1.2 Method 2: Hetarylketenes by Dehydrochlorination of Hetarylacetyl
Chlorides 473
23.12.5.1.2.1 Variation 1: Hetarylketenes by Dehydrochlorination Using a Shuttle
Procedure with a Kinetic Base, and a Stoichiometric Base — 475
23.12.5.1.3 Method 3: Hetarylketenes by Thermal Decarbonylation of
Furan 2,3 diones 475
23.12.5.1.4 Method 4: Hetarylketenes by Wolff Rearrangement of a Diazo Ketones • 476
23.12.5.1.4.1 Variation 1: Hetarylketenes by Rhodium Catalyzed Wolff Rearrangement
of a Diazo Ketones 478
23.12.5.1.4.2 Variation 2: Hetarylketenes by Wolff Rearrangement and
[2+2] Cycloaddition with Alkynes 478
23.12.5.1.4.3 Variation 3: Hetarylketenes by Wolff like Rearrangements of Triazoles
and Other Substrates 479
23.12.5.1.5 Method 5: Hetarylketenes by Carbene Carbonylation 481
23.12.5.1.6 Method 6: Hetarylketenes from Chromium Carbene Complexes 481
23.12.5.2 Applications of Product Subclass 5 in Organic Synthesis 482
23.12.5.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to
Hetarylketenes 482
23.12.5.2.2 Method 2: lmidazo[4,5 c]isoxazole Formation by Cyclization of
Hetarylketenes 482
23.12.6 Product Subclass 6: Ferrocenylketenes 483
23.i2.6i Synthesis of Product Subclass 6 483
23.12.6.1.1 Method 1: Ferrocenylketene by Activation of Ferrocenylacetic Acid 483
23.12.6.1.2 Method 2: Ferrocenylketenes by Wolff Rearrangement of a Diazo
Ketones 485
23.13 Product Class 13: Alkenylketenes
R. L Danheiser, C. B. Dudley, and W. F. Austin
23.13 Product Class 13: Alkenylketenes 493
23.13.1 Product Subclass 1: Vinylketenes 494
23.13.1.1 Synthesis of Product Subclass 1 494
23.13.1.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 494
23.13.1.1.2 Method 2: Wolff Rearrangement of a' Diazo a,p unsaturated Ketones •¦ 498
23.13.1.1.3 Method 3: Electrocyclic Ring Opening of Cyclobutenones 501
23.13.1.2 Applications of Product Subclass 1 in Organic Synthesis 504
23.13.1.2.1 Method 1: [2 + 2] Cycloadditions Leading to 4 Alkenylcyclobutanones ¦¦• 506
23.13.1.2.1.1 Variation 1: Intermolecular Cycloadditions 507
23.13.1.2.1.2 Variation 2: Intramolecular Cycloadditions 512
23.13.1.2.2 Method 2: [2+2] Cycloadditions Leading to P Lactams 520
23.13.2 Product Subclass 2:1,3 Dienylketenes and (2 Arylvinyl)ketenes 522
23.13.2.1 Synthesis of Product Subclass 2 522
23.13.2.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 525
23.13.2.1.2 Method 2: Wolff Rearrangement of 1,3 Dienyl a' Diazo Ketones 526
Table of Contents XXV
23.13.2.1.3 Method 3: Electrocyclic Ring Opening of Cyclobutenones 527
23.13.2.1.3.1 Variation 1: Electrocyclic Ring Opening of 4 Alkenyl and
4 Arylcyclobutenones 528
23.13.2.1.3.2 Variation 2: Electrocyclic Ring Opening of 2 (1,3 Dienyl)cyclobutenones
and 2 (2 Arylvinyl)cyclobutenones 530
23.13.2.1.4 Method 4: Electrocyclic Ring Opening of 6,6 Disubstituted
Cyclohexa 2,5 dien 1 ones 531
23.13.2.2 Applications of Product Subclass 2 in Organic Synthesis 533
23.13.2.2.1 Method 1: Six Electron Electrocyclizations Leading to Phenols 533
23.13.2.2.1.1 Variation 1: Of Ketenes from the Elimination of Carboxylic Acid Derivatives 534
23.13.2.2.1.2 Variation 2: Of Ketenes Generated by the Electrocyclic Ring Opening
of Cyclobutenones 539
23.13.2.2.1.3 Variation 3: Of Ketenes Generated by Electrocyclic Ring Opening
of 4 Hydroxycyclobutenones 547
23.13.3 Product Subclass 3: Alk 1 en 3 ynylketenes 555
23.13.3.1 Synthesis of Product Subclass 3 556
23.13.3.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 556
23.13.3.1.2 Method 2: Wolff Rearrangement of Diazo Ketones 557
23.13.3.1.3 Method 3: Electrocyclic Ring Opening of 4 Alkynylcyclobutenones 558
23.13.3.2 Applications of Product Subclass 3 in Organic Synthesis 559
23.13.3.2.1 Method 1: Cyclizations Leading to Quinones 559
23.14 Product Class 14: Alkyl and Cycloalkylketenes
T. T. Tidwell
23.14 Product Class 14: Alkyl and Cycloalkylketenes 569
23.14.1 Product Subclass 1: Monoalkylketenes 571
23.14.1.1 Synthesis of Product Subclass 1 571
23.14.1.1.1 Method 1: Dehydration of Alkanoic Acids 572
23.14.1.1.1.1 Variation 1: Dehydration of Carboxylic Acids Using Mukaiyama's Reagent 572
23.14.1.1.2 Method 2: Pyrolysis of Alkanoic Anhydrides 574
23.14.1.1.2.1 Variation 1: From Alkanoic Anhydrides under Perkin Conditions 575
23.14.1.1.3 Method 3: Michael Addition and Elimination Reaction of Alkanoate Esters 575
23.14.1.1.3.1 Variation 1: Ester Pyrolysis 576
23.14.1.1.4 Method 4: Dehydrohalogenation of Alkanoyl Chlorides 577
23.14.1.1.4.1 Variation 1: Dehydrochlorination Using a Shuttle Procedure with a Kinetic
Base and a Stoichiometric Base 577
23.14.1.1.5 Method5: Synthesis from Cycloalkanones and Hexa 1,5 dien 3 ones •¦• 579
23.14.1.1.5.1 Variation 1: Photolysis of Cyclobutanones 581
23.14.1.1.5.2 Variation 2: Photolysis of Cyclohexanones 582
23.14.1.1.5.3 Variation3: Photolysis of Hexa 1,5 dien 3 ones 583
23.14.1.1.6 Method 6: Dehalogenation of 2 Haloalkanoyl Halides 583
23.14.1.1.7 Method 7: Wolff Rearrangement of Diazo Ketones 585
23.14.1.1.7.1 Variation 1: Metal Catalyzed Wolff Rearrangement 585
23.14.1.1.7.2 Variation 2: Ultrasound Assisted Wolff Rearrangement 586
XXVI Table of Contents ™_
23.14.1.1.7.3 Variation 3: Microwave Enhanced Wolff Rearrangement 587
23.14.1.1.7.4 Variation 4: Photochemical Wolff Rearrangement 587
23.14.1.1.8 Method 8: Thermolysis of Alkynyl Ethers 588
23.14.1.1.9 Method 9: Synthesis from Ynolates (The Kowalski Homologation) 590
23.14.1.2 Applications of Product Subclass 1 in Organic Synthesis 590
23.14.1.2.1 Method 1: Allenyl Esters by Wittig Reactions of Monoalkylketenes 590
23.14.1.2.2 Method 2: Alkanoic Acid Derivatives by Addition of Heteroatom
Nucleophiles to Monoalkylketenes 592
23.14.1.2.2.1 Variation 1: Alkanoic Acid Derivatives by the Arndt Eistert Chain
Elongation 592
23.14.1.2.2.2 Variation 2: P Amino Acid Derivatives by the Arndt Eistert Reaction 593
23.14.1.2.2.3 Variation 3: P Amino Acid Esters by Kowalski Homologation of Esters— 595
23.14.1.2.2.4 Variation 4: Aldols via Boron Enolates from the Addition of Sulfur
Nucleophiles to Monoalkylketenes 596
23.14.1.2.2.5 Variation 5: y Lactams by Intramolecular Cyclization of Monoalkylketenes
with Nitrogen Nucleophiles 597
23.14.1.2.2.6 Variation 6: Amides by Allylic Amine Addition and Aza Claisen
Rearrangement 598
23.14.1.2.3 Method 3: 2 Halo Esters by Addition of Electrophilic Halogenating
Agents to Monoalkylketenes 599
23.14.1.2.4 Method 4: Ketones and Vinyl Ethers by Addition of Carbon Nucleophiles
to Monoalkylketenes 600
23.14.1.2.5 Method 5: Trifluoromethyl Ketones and Oxo Esters by Acylation of
Monoalkylketenes with Trifluoroacetic Anhydride 601
23.14.1.2.6 Method 6: 3 Methylene P lactones by Dimerization of Monoalkylketenes 601
23.14.1.2.7 Method 7: Cyclobutanones by [2 + 2] Cycloaddition of Monoalkylketenes
with Alkenes and Dienes 603
23.14.1.2.7.1 Variation 1: Polycyclic Ketones by Intramolecular [2 + 2] Cycloaddition of
Monoalkylketenes with Alkenyl Groups 606
23.14.1.2.8 Method 8: P Lactams by [2 + 2] Cycloaddition of Monoalkylketenes with
Imines 608
23.14.1.2.9 Method 9: fRactones by [2 + 2] Cycloaddition of Monoalkylketenes with
Aldehydes 609
23.14.1.2.10 Method 10: y Lactones by Intramolecular [3 + 2] Cyclization of Ketenes to
Cyclobutanones 611
23.14.1.2.11 Method 11: Cydopropanones by [2 + 1] Cycloaddition of
Monoalkylketenes with Diazoalkanes 612
23.14.1.2.12 Method 12: 2 Hydroxyalkanoates by [4+2] Cycloaddition of o Chloranil
with Ketene Enolates 613
23.14.2 Product Subclass 2: Dialkylketenes and (Oxomethylene)cycloalkanes ¦¦¦• 613
23.14.2.1 Synthesis of Product Subclass 2 614
23.14.2.1.1 Method 1: Dehydration of Dialkylalkanoic Acids 614
23.14.2.1.2 Method 2: Pyrolysis of 2 Alkylalkanoic Anhydrides 615
23.14.2.1.2.1 Variation 1: Decarboxylation of Dialkylmalonic Anhydrides 616
23.14.2.1.3 Method 3: Elimination Reactions of 2 Alkylalkanoate Ester Enolates 617
Table of Contents XXVII
23.14.2.1.3.1 Variation 1: Elimination from Ester Enolates Formed by Michael Addition
to Acrylates 619
23.14.2.1.4 Method 4: Dehydrochlorination of 2 Alkylalkanoyl Halides 620
23.14.2.1.5 Method 5: Pyrolysis of Ketene Dimers 625
23.14.2.1.6 Method 6: Dehalogenation of 2 Haloalkanoyl Halides 628
23.14.2.1.6.1 Variation 1: Dehalogenation of 2 Haloalkanoyl Halides with Other Metals 629
23.14.2.1.7 Method 7: Wolff Rearrangement of Diazo Ketones 630
23.14.2.1.7.1 Variation 1: Photochemical Wolff Rearrangement of Diazo Ketones 632
23.14.2.1.7.2 Variation 2: Ultrasound Enhanced Wolff Rearrangement 634
23.14.2.1.7.3 Variation 3: Photochemical Wolff Rearrangement of a Oxo Ketenes 635
23.14.2.1.8 Method 8: Oxygenation of a Dialkylthioketene 635
23.14.2.2 Applications of Product Subclass 2 in Organic Synthesis 635
23.14.2.2.1 Method 1: Carbenes by Decarbonylation of Dialkylketenes 635
23.14.2.2.2 Method 2: Carboxylic Acid Derivatives by Nucleophilic Addition to
Dialkylketenes 636
23.14.2.2.2.1 Variation 1: Carboxylic Anhydrides and Derivatives by Electrophilic
Addition to Dialkylketenes 637
23.14.2.2.2.2 Variation 2: Esters and Free Radicals by Radical Addition to Dialkylketenes 638
23.14.2.2.3 Method 3: Ketones and Vinyl Ethers by Addition of Carbon Nucleophiles
to Dialkylketenes 639
23.14.2.2.4 Method 4: Cyclobutane 1,3 diones by Dimerization of Dialkylketenes ¦•• 642
23.14.2.2.4.1 Variation 1: Cyclobutane 1,3 diones by Mixed Dimerization of
Dialkylketenes with tert Butyl(cyano)ketene 643
23.14.2.2.5 Method 5: Cyclobutanones and Cyclobutenones by [2 + 2] Cycloaddition
of Dialkylketenes with Alkenes, Dienes, Allenes, or Alkynes • • 644
23.14.2.2.5.1 Variation 1: Bicyclo[n.2.0]alkanones by Intramolecular [2 + 2] Cycloaddition
with Alkenyl Groups 649
23.14.2.2.6 Method 6: f5 Lactams by [2 + 2] Cycloaddition of Dialkylketenes with
Imines 653
23.14.2.2.6.1 Variation 1: Malonimides by [2 + 2] Cycloaddition of Dialkylketenes with
Isocyanates 654
23.14.2.2.7 Method 7: p Lactones by [2 + 2] Cycloaddition of Dialkylketenes with
Aldehydes 655
23.14.2.2.7.1 Variation 1: p Lactones by Asymmetric [2 + 2] Cycloaddition of
Dimethylketene with Chiral Aldehydes 655
23.14.2.2.8 Method 8: Cyclopropanones by [2 +1 ] Cycloaddition of Dialkylketenes
with Diazoalkanes 656
23.14.2.2.9 Method 9: Polymerization of Dialkylketenes 657
23.14.3 Product Subclass 3: Cyclopropylketene, (Cydoprop 2 enyl)ketene,
and Oxiranylketene 658
23.14.3.1 Synthesis of Product Subclass 3 658
23.14.3.M Method 1: Elimination from Cyclopropylacetates 658
23.14.3.1.2 Method 2: Dehydrohalogenation of Cyclopropylacetyl Halides 659
23.14.3.1.3 Method 3: Wolff Rearrangements of Diazo Ketones 659
23.14.3.1.3.1 Variation 1: (Cycloprop 2 enyl)ketene by Wolff Rearrangement 661
23.14.3.1.3.2 Variation 2: Oxiranylketenes by Wolff Rearrangement 662
XXVIII Table of Contents
23.14.3.1.4 Method 4: Photochemical Rearrangement of 5,5 Dimethylcyclopent 2
enone 662
23.14.3.1.4.1 Variation 1: Photolysis of Cyclopentadienones 662
23.14.3.2 Applications of Product Subclass 3 in Organic Synthesis 663
23.14.3.2.1 Method 1: Bicyclooctadienones and Cycloheptadienones from
Cyclopropylketenes by Cope Rearrangement 663
23.14.4 Product Subclass 4: (Fluoroalkyl)ketenes 665
23.14.4.1 Synthesis of Product Subclass 4 666
23.14.4.1.1 Method 1: Dehydration of Fluoroalkanoic Acids 666
23.14.4.1.2 Method 2: Dehalogenation of 2 Haloacyl Halides 666
23.14.4.1.3 Method 3: Wolff Rearrangement of Diazo Ketones 667
23.14.4.1.3.1 Variation 1: Bis(trifluoromethyl)ketene by Wolff Type Rearrangement
upon Oxidation of an Alkyne 667
23.14.4.1.4 Method 4: Hydrolysis of a Perfluoroalkene 668
23.14.4.1.5 Method 5: Acyl(trifluoromethyl)ketenes by Cleavage of a
1,3 Dioxin 4 one 668
23.14.4.2 Applications of Product Subclass 4 in Organic Synthesis 668
23.14.4.2.1 Method 1: Fluoroalkyl Cyclobutanones, Cyclobutenones, and Derivatives
by [2 + 2] Cycloaddition Reactions of (Fluoroalkyl)ketenes — 668
23.14.4.2.2 Method 2: (Trifluoromethyl)malonates by Nucleophilic Additions to a
(Trifluoromethyl)ketene 671
23.15 Product Class 15: Bisketenes
T. T. Tidwell
23.1S Product Class 15: Bisketenes 679
23.15.1 Product Subclass 1:1,2 Bisketenes 681
23.15.1.1 Synthesis of Product Subclass 1 681
23.15.1.1.1 Method 1: 1,2 Bisketenes by Thermal Ring Opening of
Cyclobutene 1,2 diones 682
23.15.1.1.1.1 Variation 1: Stabilized 1.2 Bisketenes by Thermal Ring Opening of
Cyclobutene 1,2 diones 683
23.15.1.1.2 Method 2: 1,2 Bisketenes by Photochemical Ring Opening of
Cyclobutene 1,2 diones 684
23.15.1.1.3 Method 3: Metal Complexed 1,2 Bisketene 687
23.15.1.1.4 Method 4: 1,2 Bisketenes by Wolff Rearrangement of Bis(diazo ketones) 687
23.15.1.2 Applications of Product Subclass 1 in Organic Synthesis 688
23.15.1.2.1 Method 1: Acids, Esters, and Amides by Nucleophilic Additions to
1,2 Bisketenes 688
23.15.1.2.1.1 Variation 1: (Carboxy)ketenes and Succinic Anhydrides by Water Addition
to 1,2 Bisketenes 691
23.15.1.2.2 Method 2: Diamides by Amine Addition to 1,2 Bisketenes 692
23.15.1.2.2.1 Variation 1: Carbamoyl Substituted Esters by Successive Amine and
Alcohol Addition 692
Table of Contents XXIX
23.15.1.2.2.2 Variation 2: A Cyclic Carbamoyl Ester by Addition of an Amino Alcohol
to a 1,2 Bisketene 693
23.15.1.2.3 Method 3: A Fumaroyl Bromide by Bromine Addition to a 1,2 Bisketene • 693
23.15.1.2.4 Method 4: Maleic Anhydride Formation by Aminoxyl Radical Addition
to a 1,2 Bisketene 694
23.15.1.2.5 Method 5: Furanone Formation by Dimerization of 1,2 Bisketenes 694
23.15.1.2.6 Method 6: Naphthofuranones by [4+2] Cycloaddition of 1,2 Bisketenes
with Pendant Alkenes 695
23.15.1.2.7 Method 7: Cyclopropenes and Quinones by [2 + 1] and [4 + 2]
Cycloaddition of 1,2 Bisketenes with Alkynes 695
23.15.1.2.8 Method 8: A P Lactone by [2 + 2] Cycloaddition of a 1,2 Bisketene with
Acetaldehyde 697
23.15.1.2.9 Method 9: Cyclopentenediones by [4+1 ] Cycloaddition of
1,2 Bisketenes with Carbenes and Diazoalkanes 697
23.15.1.2.10 Method 10: Cyclopropenones and Alkynes by Photolysis of 1,2 Bisketenes 697
23.15.2 Product Subclass 2:1,3 and Higher Bisketenes 699
23.15.2.1 Synthesis of Product Subclass 2 699
23.15.2.1.1 Method 1: A Bisketene by Dehydration of a Dicarboxylic Acid 699
23.15.2.1.2 Method 2: A Bisketene by Elimination from a Bis(isopropenyl) Ester 700
23.15.2.1.3 Method 3: Bisketenes by Dehydrochlorination of Dicarboxylic Acid
Chlorides 701
23.15.2.1.3.1 Variation 1: Bisketenes by Dehydrochlorination of Dicarboxylic Acid
Chlorides by a Shuttle Procedure with a Kinetic Base and
a Stoichiometric Base 702
23.15.2.1.3.2 Variation 2: 1,4 Bis(oxovinyl)benzenes by Dehydrochlorination 705
23.15.2.1.4 Method 4: Bisketenes by Ring Opening of Benzo 1,2 quinones 705
23.15.2.1.5 Method 5: Bisketenes by Wolff Rearrangement of Bis(diazo ketones) •••• 706
23.15.2.1.6 Method 6: Bis and Tris(oxovinyl)silanes by Thermolysis of
(Ethoxyethynyl)silanes 707
23.15.2.1.7 Method 7: A 1,5 Bisketene by [4+2] Cycloaddition of Norbornadiene
with a 1,3,4 Oxadiazine Followed by Nitrogen Elimination • • • 710
23.15.2.1.8 Method 8: A Bis(allenylketene) from a Bis(methylenecyclobutenone) • • • 710
23.15.2.2 Applications of Product Subclass 2 in Organic Synthesis 711
23.15.2.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to Bisketenes 711
23.15.2.2.1.1 Variation 1: Polyamides and Polyesters from Bisketenes and Diamines or
Diols 711
23.15.3 Product Subclass 3: Bis(oxomethylene)cyclohexanes and
cyclohexadienes 712
23.15.3.1 Synthesis of Product Subclass 3 713
23.15.3.1.1 Method 1: Bis(oxomethylene)cyclohexanes and cyclohexadienes by
Dehydrochlorination of Dicarboxylic Acid Chlorides 713
23.15.3.1.2 Method 2: Bis(oxomethylene)cydohexadienes by Dehalogenation of
Terephthaloyl Halides 714
23.15.3.1.3 Method 3: 1,2 Bis(oxomethylene)cyclohexane by Ring Opening of a
Cyclobutene 1,2 dione 714
XXX Table of Contents
23.15.3.1.4 Method 4: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Ring Opening
of aCyclobutene 1,2 dione 715
23.15.3.1.4.1 Variation 1: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Thermal
Nitrogen Loss from Phthalazine 1,4 dione 716
23.15.3.1.5 Method 5: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Cyclophane
Cleavage 716
23.15.3.1.6 Method 6: Bis(oxomethylene)cycloalkanes by Double Wolff
Rearrangement 716
23.15.3.2 Applications of Product Subclass 3 in Organic Synthesis 717
23.15.3.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to Bisketenes 717
23.15.3.2.2 Method 2: [4+2] Cycloadditions of 1,2 Bisketenes with Alkenes and
Benzoquinones 718
23.15.3.2.3 Method 3: Spiro[cyclopropane 1,T(3'H) isobenzofuran] 3' ones by
Cycloaddition of a 1,2 Bisketene with Alkenes 719
23.15.3.2.4 Method 4: A 1,3,5 Oxathiazine by [4+2] Cycloaddition of a Bisketene
with an Isocyanate 721
23.15.3.2.5 Method 5: Benzyne by Photochemical Decarbonylation of
5,6 Bis(oxomethylene)cydohexa 1,3 diene 721
23.153.2.5.1 Variation 1: A Bicyclic Enyne by Photochemical Decarbonylation of a
Bisketene 721
23.15.3.2.6 Method 6: Polymerization of a 1,4 Bisketene by [2 + 2] Cyclodimerization 722
23.15.4 Product Subclass 4: Other Bisketenes 722
23.i5.4i Synthesis of Product Subclass 4 722
23.15.4.1.1 Method 1: Bis(acylketenes) by Thermolysis of Bis(dioxinones) and
Bis(Meldrum's acid) Derivatives 722
23.15.4.1.2 Method 2: A Tris(acylketene) by Thermolysis of a Triester 726
23.15.4.1.3 Method 3: A Bis(acylketene) by Carbon Dioxide Addition to a
Diynediamine 726
23.15.4.1.4 Method 4: Bis(acylketenes) by Wolff Rearrangement of Bis(diazo)
Tetraketones 727
23.15.4.1.4.1 Variation 1: Cyclic Bis(acylketene) Formation by a Wolff Type
Rearrangement 727
23.15.4.1.5 Method 5: Bis(dienylketenes) by Photolysis of Bis(cyclohexadienones) • • 728
23.15.4.1.6 Method 6: A Bis(oxovinyl)platinum Complex by Addition of a Ketene
to an (Oxovinyl)platinum Complex 729
23.15.4.1.7 Method 7: Bis(ketenechromium) Complexes from
Bis(alkylidenechromium) Complexes 730
23.16 Product Class 16: Sulfur, Selenium, and Tellurium Analogues of Ketenes
C. Spanka and E. Schaumann
23.16 Product Class 16: Sulfur, Selenium, and Tellurium Analogues of Ketenes ¦ 735
23.16.1 Product Subclass 1: Thioketenes 735
23.16.1.1 Synthesis of Product Subclass 1 736
23.16.1.1.1 Method 1: Sulfuration of Ketenes 736
Table of Contents XXXI
23.16.1.1.2 Method 2: Synthesis from Dithiocarboxylates 738
23.16.1.1.3 Method 3: Elimination Reactions of Ketene S,X Acetals 739
23.16.1.1.4 Method 4: Synthesis by Cycloreversion 740
23.16.1.1.4.1 Variation 1: [2 + 2] Cycloreversion of 2,4 Bis(alkylidene) 1,3 dithietanes
(Thioketene Dimers) or4 Alkylidene 1,3 dithietan 2 ones ¦•¦ 740
23.16.1.1.4.2 Variation 2: [3 + 2] Cycloreversion of 2 Alkylidene 1,3 dithiolane
Derivatives 742
23.16.1.1.4.3 Variation 3: 1,2,3 Thiadiazoles as Stable Thioketene Precursors
(Thio Wolff Rearrangement) 746
23.16.1.1.5 Method 5: Treatment of Alkylidenephosphoranes with Carbon Disulfide ¦ 750
23.16.1.1.6 Method 6: Thioketenes via Alkynyl Sulfides 751
23.16.1.1.6.1 Variation 1: Protonation orSilylation of Alk 1 ynethiolates Followed
by [1,3] Hydrogen/Silicon Shift 753
23.16.1.1.6.2 Variation 2: Thia Cope Rearrangement of Alkynyl Allyl Sulfides 754
23.16.1.1.7 Methods 7: Other Methods 758
23.16.2 Product Subclass 2: Cumulated Thioketenes and Their Derivatives 760
23.16.2.1 Synthesis of Product Subclass 2 760
23.16.2.1.1 Methodi: Synthesis of Alkylidenethioketenes 760
23.16.2.1.2 Method 2: Synthesis of (Arylimino)thioketenes 761
23.16.2.1.3 Method 3: Synthesis of Carbon Subsulfide (Propadienedithione) 762
23.16.3 Product Subclass 3: Thioketene S Oxides 764
23.16.3.1 Synthesis of Product Subclass 3 764
23.16.3.1.1 Methodi: Direct Oxidation of Thioketenes 764
23.16.3.1.2 Method 2: [3+2] Cycloreversion of 1,3 Dithiolane 1,1,3 Trioxides 765
23.16.3.1.3 Method 3: Retro Diels Alder Reaction 765
23.16.4 Product Subclass 4: Selenoketenes 766
23.16.4.1 Synthesis of Product Subclass 4 766
23.16.4.1.1 Method 1: Rearrangement of Alkynyl Selenides 767
23.16.4.1.2 Method 2: [3,3] Sigmatropic Rearrangement of Alkynyl Allyl Selenides
(Selena Cope Rearrangement) 769
23.16.4.1.3 Method 3: Nitrogen Extrusion from 1,2,3 Selenadiazoles 772
23.16.5 Product Subclass 5: Telluroketenes 776
23.17 Product Class 17: Ketenimines
H. Perst
23.17 Product Class 17: Ketenimines 781
23.17.1 Product Subclass 1: Monoketenimines 783
23.17.1.1 Synthesis of Product Subclass 1 783
23.17.1.1.1 Synthesis by Formation of the C=C Bond 784
23.17.1.1.1.1 Methodi: Dehydrocyanation of Imidoyl Cyanides 784
23.17.1.1.1.2 Method 2: Dehydration of Carboxamides by Oxophilic Reagents in the
Presence of Tertiary Amines 785
XXXII Table of Contents
23.17.1.1.1.2.1 Variation 1: Using Triphenylphosphine Carbon
Tetrachloride Triethylamine 787
23.17.1.1.1.2.2 Variation 2: Using Triphenylphosphine Bromine Triethylamine 788
23.17.1.1.1.2.3 Variation 3: Using Diphosgene Triethylamine 791
23.17.1.1.1.3 Method 3: p Elimination from Imidocarboxylic Acid Derivatives 793
23.17.1.1.1.3.1 Variation 1: Dehydrohalogenation of Imidoyl Halides 793
23.17.1.1.1.3.2 Variation 2: Dehalogenation of a Haloimidoyl Halides 795
23.17.1.1.1.3.3 Variation 3: p Elimination from Imidocarboxylic Acid Esters 796
23.17.1.1.1.4 Method 4: P Elimination from Other Precursors via Imidocarboxylic
Acid Derivatives Formed In Situ 798
23.17.1.1.1.4.1 Variation 1: From Oximes 798
23.17.1.1.1.4.2 Variation 2: From 2,2 Dihaloaziridines 799
23.17.1.1.1.5 Method 5: Elimination of Hydrogen Sulfide from Thioamides 801
23.17.1.1.1.5.1 Variation 1: From Thioamides via Imidoyl Chlorides 801
23.17.1.1.1.5.2 Variation 2: From Methyl Imidothioesters 802
23.17.1.1.1.6 Method 6: Connective Alkene Formation by Reaction of Phosphonium
Ylides or Related Reagents with Azaheterocumulenes 804
23.17.1.1.1.6.1 Variation 1: Ketenimines from Wittig Reaction of Alkylidenetriphenyl
phosphoranes with Isocyanates 804
23.17.1.1.1.6.2 Variation 2: Reaction of Alkylidenephosphoranes with Isothiocyanates
or Carbodiimides 808
23.17.1.1.1.6.3 Variation 3: Horner Wittig Reaction of Isocyanates with Carbanions
Derived from Diethyl Phosphonates 809
23.17.1.1.1.7 Method 7: Cycloreversion 809
23.17.1.1.1.8 Method 8: Cheletropic Reactions (Sulfur Extrusion from
2,5 Dihydroisothiazol 5 imines) 811
23.17.1.1.1.9 Method 9: Addition of Isocyanides to Carbenes 812
23.17.1.1.1.10 Method 10: Addition of Isocyanides to Suitable Carbon Fragments
in the Coordination Sphere of Transition Metal Complexes • • ¦ 814
23.17.1.1.1.10.1 Variation 1: Addition of Carbenes to Transition Metal lsocyanide
Complexes 814
23.17.1.1.1.10.2 Variation 2: Addition of Isocyanides to Transition Metal Carbene
Complexes 815
23.17.1.1.1.10.3 Variation 3: Rearrangement of a Transition Metal lsocyanide Complex • • • 816
23.17.1.1.1.10.4 Variation 4: Palladium Assisted Reactions of Isocyanides with Alkyl
Chlorides 817
23.17.1.1.1.11 Method 11: Addition of Isocyanides to Alkynes 818
23.17.1.1.1.12 Method 12: Addition of Isocyanides to Cyclopropene Derivatives 820
23.17.1.1.1.13 Method 13: Iminocarbene Ketenimine Rearrangement 821
23.17.1.1.1.13.1 Variation 1: Photochemical Transformation of 2 (Cyanoimino) 1 diazoal
kanes 821
23.17.1.1.1.13.2 Variation 2: Thermal or Photochemical Transformation of
1 Aryl 1,2,3 triazolesand 1 H Benzotriazoles 822
23.17.1.1.2 Synthesis by Formation of the C=N Bond 824
23.17.1.1.2.1 Method 1: Dehydrocyanation of a Cyanoenamines 825
23.17.1.1.2.2 Method 2: Dehydrohalogenation of a Haloenamines 826
23.17.1.1.2.3 Method 3: Eliminations from Ketene N,5 Acetals 828
Table of Contents XXXIII
23.17.1.1.2.4 Method 4: Connective Imine Formation by Aza Wittig Reaction of
Iminophosphoranes or Related Compounds with Ketenes — 831
23.17.1.1.2.4.1 Variation 1: With Preformed Iminophosphoranes and Preformed Ketenes 831
23.17.1.1.2.4.2 Variation 2: With Preformed Iminophosphoranes and In Situ Generated
Ketenes 833
23.17.1.1.2.4.3 Variation 3: With In Situ Generated Iminophosphoranes and Preformed
Ketenes 833
23.17.1.1.2.4.4 Variation 4: Reaction of N Substituted Diethyl Phosphoramidate Anions
with Ketenes 837
23.17.1.1.2.5 Method 5: Connective Imine Formation by the Reaction of Thioketenes
with Sulfur Diimides 838
23.17.1.1.2.6 Method 6: Deprotonation and Ring Opening of Isoxazolium Salts 839
23.17.1.1.2.7 Method 7: Cycloreversion 840
23.17.1.1.2.8 Method 8: Cheletropic Reactions 840
23.17.1.1.2.9 Method 9: Thermolysis of Vinyl Azides 843
23.17.1.1.2.10 Method 10: Photolysis of Vinyl Azides or Aryl Azides 844
23.17.1.1.3 Synthesis by Formation of the C=C and C=N Bonds 845
23.17.1.1.3.1 Method 1: Addition Elimination Reactions with Nitriles 845
23.17.1.1.3.1.1 Variation 1: Via Nitrilium Ions and Subsequent Deprotonation at the
P Carbon Atom 845
23.17.1.1.3.1.2 Variation 2: Via Nitrile Anions and Subsequent Addition of Electrophiles
to the Nitrogen Atom 846
23.17.1.1.3.1.3 Variation 3: Addition of Trialkyl Phosphites to a Halo Nitriles and
Elimination of Haloalkanes 849
23.17.1.1.3.2 Method 2: 1,4 Addition to a.p Unsaturated Nitriles 851
23.17.1.1.3.3 Method 3: [2,3] Sigmatropic Rearrangement of 1 Cyanoalkyl
Methylenesulfur Ylides 852
23.17.1.2 Applications of Product Subclass 1 in Organic Synthesis 854
23.17.1.2.1 Method 1: Addition of Protic Nucleophiles and Related Compounds •¦¦• 854
23.17.1.2.2 Method 2: [2+2] Cycloaddition Reactions of Ketenimines 856
23.17.1.2.2.1 Variation 1: With Alkenes or Alkynes 856
23.17.1.2.2.2 Variation 2: With Carbonyl Compounds 858
23.17.1.2.2.3 Variation 3: With Thiocarbonyl Compounds 859
23.17.1.2.2.4 Variation 4: With Imines 861
23.17.1.2.2.5 Variation 5: With N=X Systems 862
23.17.1.2.2.6 Variation 6: With Heterocumulenes 864
23.17.1.2.3 Method 3: [3+ 2] Cycloaddition Reactions of Ketenimines 865
23.17.1.2.3.1 Variation 1: With 1,3 Dipoles 865
23.17.1.2.3.2 Variation 2: With Three Membered Heterocycles 867
23.17.1.2.3.3 Variation 3: Via Intramolecular Reactions of C (Aziridin 1 yliminojketen
imines 869
23.17.1.2.4 Method 4: [4+2] Cycloaddition Reactions Using Ketenimines as
Dienophiles 870
23.17.1.2.5 Method 5: [4 + 2] Cycloaddition Reactions Using Ketenimines as
1,3 Dienes 871
23.17.1.2.5.1 Variation 1: From a 1,3 Diene Formed by the Ketenimine C=C Bond
and a Suitable C Substituent 874
XXXIV Table of Contents
23.17.1.2.5.2 Variation 2: From a 1,3 Diene Formed by the Ketenimine C=C Bond
and a C Aryl Substituent; Intramolecular [4+2] Cycloaddition
Reactions 877
23.17.1.2.5.3 Variation 3: From a 1,3 Diene Formed by the Ketenimine C=N Bond
and a Suitable N Substituent 879
23.17.1.2.5.4 Variation 4: From a 1,3 Diene Formed by the Ketenimine C=N Bond
and an N Aryl Substituent 882
23.17.1.2.6 Method 6: Rearrangements of Ketenimines 884
23.17.1.2.7 Method 7: Reactions with Loss of the N Substituent 885
23.17.1.2.7.1 Variation 1: Thermal Cleavage 885
23.17.1.2.7.2 Variation 2: Addition Elimination Reactions of /V Silyl or
N Stannylketenimines 886
23.17.1.2.7.3 Variation 3: Alk 2 enenitriles from C,C,A/ Tris(trimethylsilyl)ketenimine
and Aldehydes 888
23.17.2 Product Subclass 2: Bisiminopropa 1,2 dienes 889
23.17.2.1 Synthesis of Product Subclass 2 889
23.17.2.1.1 Method 1: Thermolysis of Isoxazolonoketene N,S Acetals 889
Keyword Index 899
Author Index 1013
Abbreviations 1049 |
| adam_txt |
_ ^ ^ ^ | ^ ix
Table of Contents
Introduction
R. L. Danheiser
Introduction 1
23.1 Product Class 1: Ketene
T. T. Tidwell
23.1 Product Class 1: Ketene 15
23.1.1 Synthesis of Product Class 1 18
23.1.1.1 Method 1: Ketene from Acetic Acid, Acid Anhydrides, and Esters 19
23.1.1.2 Method 2: Dehydrohalogenation of Acetyl Halides 19
23.1.1.2.1 Variation 1: lonization of Acetyl Halides to Acylium Ions and Deprotonation 21
23.1.1.3 Method 3: Pyrolysis of Ketene Dimer 22
23.1.1.4 Method 4: Photolysis of Cyclobutanones and Thermolysis 22
23.1.1.5 Method 5: Dehalogenation of Haloacetyl Halides 23
23.1.1.6 Method 6: Pyrolysis of Acetone 24
23.1.1.7 Method 7: Wolff Rearrangement of Diazoacetaldehyde 24
23.1.1.8 Method 8: Elimination from Alkynyl Ethers 25
23.1.2 Applications of Product Class 1 in Organic Synthesis 26
23.1.2.1 Method 1: Nucleophilic Addition to Ketene 26
23.1.2.1.1 Variation 1: Enol Acetates from the Reaction of Ketene with Aldehydes
and Ketones 28
23.1.2.2 Method 2: Electrophilic and Radical Additions to Ketene 29
23.1.2.3 Method 3: Dimerization by [2 + 2] Cycloaddition 32
23.1.2.4 Method 4: [2 + 2] Cycloaddition of Ketene with Alkenes and Dienes 32
23.1.2.5 Method 5: [2 + 2] Cycloaddition of Ketene with Alkynes 34
23.1.2.6 Method 6: [2 + 2] Cycloaddition of Ketene with Imines 35
23.1.2.7 Method 7: [2 + 2] and [4+2] Cycloaddition of Ketene with Carbonyl Croups 36
23.1.2.7.1 Variation 1: [3 Hydroxy Esters by Titanium Alkoxide Induced Addition
of Carbonyl Compounds to Ketene 42
23.1.2.8 Method 8: [2 + 2] Cycloaddition of Ketene with Azobenzenes 42
23.1.2.9 Method 9: [2 + 1] Cycloaddition of Ketene with Sulfur Dioxide 43
23.1.2.10 Method 10: [2 +1 ] Cycloaddition of Ketene with Diazomethane 44
23.1.2.11 Method 11: [4 + 2] Cycloaddition of Ketene with Heterodienes 44
23.1.2.12 Method 12: Wittig Reaction of Ketene with a Chiral Phosphorane 45
23.1.2.13 Method 13: Dimetal Ketenides from Ketene and Metal Salts 45
23.1.2.14 Method 14: Decarbonylation of Ketene 46
X Table of Contents
23.2 Product Class 2: Silylketenes
D. M. George and R. L. Danheiser
23.2 Product Class 2: Silylketenes 53
23.2.1 Product Subclass 1: Silyl Substituted Aldoketenes 54
23.2.1.1 Synthesis of Product Subclass 1 54
23.2.1.1.1 Method 1: Dehydrohalogenation of Acyl Halides 54
23.2.1.1.2 Method 2: Dehydration of Silylacetic Acids 55
23.2.1.1.3 Method 3: Thermolysis of 1 Alkoxy 2 silylacetylenes 55
23.2.1.1.4 Method 4: 1,3 Silyl Shift of (Trimethylsiloxy)acetylene 57
23.2.1.1.5 Method 5: Thermolysis of Silylacetic Anhydrides 57
23.2.1.2 Applications of Product Subclass 1 in Organic Synthesis 58
23.2.1.2.1 Methodi: [2 + 2] Cycloadditions Leading to fRactones 58
23JM.2.2 Method2: [2 + 2] Cycloadditions Leading to {5 Lactams 64
23JU.2.3 Method 3: [2 + 2] Cycloadditions Leading to Cyclobutanones 65
23.2.1.2.4 Method 4: Formation of Allenes via Wittig Reaction with Phosphorus
Ylides 65
23.2.1.2.5 Method 5: Formation of Ketenimines via Reaction with
Iminophosphoranes 66
23.2.1.2.6 Method 6: Formation of Cyclopropanones and Cyclobutanones
via Reaction with Diazo Compounds 67
23.2.1.2.7 Method 7: Formation of a Silyl Ketones 68
23.2.1.2.8 Method 8: Formation of 2H 1 Benzopyran 2 ones from Phenols 70
23.2.1.2.9 Method 9: (Trimethylsilyl)acetylation of Alcohols and Amines 71
23J.2 Product Subclass 2: (Silyl)(trialkylmetal)ketenes 72
23.2.2.1 Synthesis of Product Subclass 2 72
23.2.2.1.1 Method 1: Elimination from (Silyl)(trialkylmetal)acetates 72
23.2.2.1.2 Method 2: Trapping of Lithium 2 Lithioacetylen 1 olate Generated
from 2 Phenyl 2,3 dihydrofurans or 3 Phenylisoxazoles 72
23.2.2.1.3 Method 3: Carbonylation and Trapping of Lithiated Diazo(trimethyl
silyl)methane 73
23.2.2.1.4 Method 4: Lithiation of (Trialkylsilyl)ketenes and Trapping with
Chlorosilanes 74
23.2.2.1.5 Method 5: Synthesis of Bis(silyl)ketenes from Other Bis(silyl)ketenes
via Potassium 2 Silylacetylen 1 olates 74
23.2.3 Product Subclass 3: (Aryl) and (Alkyl)silylketenes 76
23.2.3.1 Synthesis of Product Subclass 3 76
23.2.3.1.1 Methodi: 1,3 Silyl Shift of 1 (Siloxy)alk 1 ynes 76
23.2.3.1.2 Method 2: Wolff Rearrangement of a Diazo a silyl Ketones 77
23J.3.1.2.1 Variation 1: By Thermolysis 77
23J.3.1.2.2 Variation 2: By Photolysis 77
23.2.3.1.2.3 Variation 3: By Metal Catalysis 78
23.2.3.2 Applications of Product Subclass 3 in Organic Synthesis 79
23JJ.2.1 Methodi: [2 + 2] Cycloadditions Leading to p Lactones 79
Table of Contents XI
23.2.3.2.2 Method2: [4 + 1] Annulation Leading to 1,3 Dihydro 2H inden 2 ones ••• 80
23.2.4 Product Subclass 4: Silyl(vinyl)ketenes 84
23.2.4.1 Synthesis of Product Subclass 4 84
23.2.4.1.1 Method 1: Dehydrohalogenationof a Silyl a,P unsaturated Acid Chlorides 84
23.2.4.1.2 Method 2: Wolff Rearrangement of a Diazo a silyl a'.P' Unsaturated
Ketones 85
23.2.4.1.3 Method 3: Electrocyclic Ring Opening of 2 Silylcyclobut 2 enones 86
23.2.4.1.4 Method 4: Reaction of Bis(silyl)acetylenes with Chromium Carbene
Complexes 87
23.2.4.2 Applications of Product Subclass 4 in Organic Synthesis 88
23.2.4.2.1 Method 1: Formation of Cyclohexenones and Phenols by
[4 + 2]Cycloadditions 88
23.2.4.2.2 Method 2: Formation of 5,6 Dihydro 2H pyran 2 ones and
5,6 Dihydropyridin 2(1H) ones by [4 + 2] Cycloadditions 89
23.2.4.2.3 Method 3: Formation of Cyclopent 2 en 1 ones by [4+1] Annulation — 91
23.2.5 Product Subclass 5: Miscellaneous Silylketenes 96
23.2.5.1 Synthesis of Product Subclass 5 96
23.2.5.1.1 Method 1: Synthesis of Bromo(trialkylsilyl)ketenes by
Dehydrohalogenation 96
23.2.5.1.2 Method 2: Synthesis of Alkoxy(triarylsilyl)ketenes from Pentacarbonyl
Complexes 96
23.2.5.1.3 Methods 3: Miscellaneous Reactions 96
233 Product Class 3: Halogen Substituted Ketenes
T. T. Tidwell
233 Product Class 3: Halogen Substituted Ketenes 101
23J.i Product Subclass 1: Fluoro and Difluoroketenes 104
233.1.1 Synthesis of Product Subclass 1 105
233.1.1.1 Method 1: Fluoroketene by Pyrolysis of Fluoroacetic Anhydride 105
233.1.1.2 Method 2: Fluoroketene by Dehydrochlorination of Fluoroacetyl Chloride 105
233.1.1.3 Method 3: Difluoroketene from 1,1,2 Trifluoro 2 (trifluoromethoxy)
ethene 107
233.1.1.4 Method 4: Difluoroketene by Photolysis of Perfluorocyclobutanone 107
233.1.1.5 Method 5: Difluoroketene by Dehalogenation of Bromo(difluoro)acetyl
Chloride with Zinc 108
233.1.1.6 Method 6: Acyl(fluoro)ketenes by Thermolysis of a Fluorodioxinones ••• 108
233.1.1.7 Method 7: Fluoro(pentafluoroethyl)ketene by Fluoride Induced
Dephosphorylation 109
233.1.1.8 Method 8: Difluoroketene by Photoisomerization/Oxygenation of
Difluoroacetylene 110
233.1.1.9 Method 9: Fluoro(1,2,3,4,4 pentafluorobuta 1,3 dienyl)ketenefrom
Perfluorocyclohexa 2,4 dienone 110
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 111
XII Table of Contents
233.1.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloaddition of Fluoroketenes
with Alkenes 111
233.1.2.2 Method 2: P Lactams by [2 + 2] Cycloaddition of Fluoroketenes with
Imines 113
233.2 Product Class 2: Chloro and Dichloroketenes 113
233.2.1 Synthesis of Product Subclass 2 114
233.2.1.1 Method 1: Alkyl(chloro)ketenes by Dehydration of Carboxylic Acids 115
233.2.1.2 Method 2: Chloroketenes by Dehydrochlorination of Chloroalkanoyl
Halides 116
233.2.1.2.1 Variation 1: Chloroketene by Pyrolytic Dehydrochlorination of
Chloroacetyl Chloride 118
233.2.1.2.2 Variation 2: Substituted Choroketenes by Dehydrochlorination of
2 Chloroacyl Chlorides 119
233.2.1.3 Method 3: Dichloroketene by Photolysis of a Cyclic Carbonate 119
233.2.1.4 Method 4: Dichloroketene by Dehalogenation of Trichloroacetyl Halides
with Zinc 119
233.2.1.4.1 Variation 1: Chloroketenes by Dechlorination of 2 Chloroacyl Chlorides
with Diphenyl(trimethylsilyl)phosphine 124
233.2.1.5 Method 5: Chloro(cyano)ketene by Thermolysis of
4 Azido 3 chloro 5 methoxyfuran 2(5H) one 125
233.2.2 Applications of Product Subclass 2 in Organic Synthesis 126
233.2.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloadditions of Choroketenes
with Alkenes and Dienes 126
233.2.2.2 Method 2: Methylenecyclobutanones by [2 + 2] Cycloaddition of
Chloroketenes with Allenes 137
233.2.2.3 Method 3: Cyclobutenones by [2 + 2] Cycloaddition of Chloroketenes
with Alkynes 138
233.2.2.4 Method 4: P Lactams by [2 + 2] Cycloaddition of Chloroketenes with
Imines 140
233.2.2.4.1 Variation 1: P and 5 Lactams by [2 + 2] and [4 + 2] Cycloaddition
Reactions of Chloroketenes with Vinylic Imines 141
233.2.2.4.2 Variation 2: Y"Lactams ar|d yLactones by [3 + 2] Cycloaddition of
Dichloroketene with N Vinylsulfimides 143
233.2.2.5 Method 5: P Lactones by [2 + 2] Cycloaddition of Chloroketenes with
Carbonyl Compounds 146
233.2.2.6 Method 6: y Lactones from Dichloroketene with Vinyl Sulfoxides 148
233.2.2.6.1 Variation 1: y Lactones from Dichloroketene with Chiral Vinyl Sulfoxides • 149
233.2.2.7 Method 7: Thioesters by Ketene Claisen Reaction of Dichloroketene
with Allyl Sulfides 150
233.2.2.8 Method 8: A Macrocyclic Lactone by the Ketene Claisen Reaction of
Dichloroketene with a Vinyltetrahydropyran 151
233.2.2.9 Method 9: y Lactones and Lactams by the Reactions of Dichloroketene
with Three Membered Heterocycles 152
233.2.2.9.1 Variation 1: A Lactam by the Reaction of Dichloroketene with a
Vinylaziridine 153
Table of Contents XIII
233.2.2.9.2 Variation 2: Ketene Acetals from Cycloaddition of Chloro(cyano)ketene
with 2 Phenyloxirane 154
233.3 Product Subclass 3: Bromo and lodoketenes 154
233.3.1 Synthesis of Product Subclass 3 154
233.3.1.1 Method 1: Bromo and lodoketenes by Dehydrochlorination of
Haloacetyl Chlorides 154
233.3.1.1.1 Variation 1: Bromoketene by Dehydrochlorination of Bromoacetyl
Chloride with a Strong Stoichiometric Base and a Shuttle Base 156
233.3.1.2 Method 2: Bromoketene by Pyrolysis of 2 Bromocyclobutanone 157
233.3.1.3 Method 3: Bromoketenes by Dehalogenation of Haloacyl Halides 157
233.3.1.3.1 Variation 1: Dibromoketene by Triphenylphosphine lnduced Elimination
from Trimethylsilyl Tribromoacetate 158
233.3.1.4 Method 4: An Aryl(bromo)ketene from a 3 Aryloxirane 2,2 dicarbonitrile 158
233.3.2 Applications of Product Subclass 3 in Organic Synthesis 159
233.3.2.1 Method 1: Cyclobutanones by [2 + 2] Cycloaddition of Bromoketenes
with Alkenes or Dienes 159
233.3.2.1.1 Variation 1: Cyclohex 2 en 1 ones by [4 + 2] Cycloaddition of
Bromo(vinyl)ketenes with Enamines 160
233.3.2.2 Method 2: |3 and 8 Lactams by Cycloaddition of Bromoketenes with
Imines 161
233.3.2.3 Method 3: [3 + 2] Cycloaddition of Aryl(bromo)ketenes with
Pyridiniumolate Betaines 161
233.3.2.4 Method 4: Chiral Aryl(halo)acetates by Stereoselective Addition of Chiral
Alcohols to Bromo and lodoketenes 162
233.3.2.5 Method 5: A Chiral Bromo(chloro)acetate by Stereoselective
Chlorination of Bromoketene 163
233.3.2.6 Method 6: Mixed Dimerization of Bromo(tert butyl)ketenes with
tert Butylketene 163
23.4 Product Class 4: Oxygen Substituted Ketenes
C. Palomo, M. Oiarbide, and J. M. Aizpurua
23.4 Product Class 4: Oxygen Substituted Ketenes 169
23.4.1 Synthesis of Product Class 4 170
23.4.1.1 Method 1: Elimination Reactions of Carboxylic Acids or Their Derivatives 170
23.4.1.1.1 Variation 1: Dehydration of Carboxylic Acids by Activating Reagents 170
23.4.1.1.2 Variation 2: Dehydrohalogenation of Carboxylic Acid Chlorides with
Tertiary Amines in Solution 172
23.4.1.1.3 Variation 3: Dehydrohalogenation of Carboxylic Acid Chlorides with
Solid Supported Bases 174
23.4.1.2 Method 2: Photolysis of Metal Carbene Complexes 177
23.4.1.3 Method 3: Dirhodium Tetraacetate Catalyzed Decomposition of a Diazo
Anhydrides 179
23.4.1.4 Methods 4: Miscellaneous Methods 181
23.4.2 Applications of Product Class 4 in Organic Synthesis 181
XIV Table of Contents
23.4.21 Method 1: [2 + 2] Cycloaddition Reactions Leading to Cyclobutanones,
P Lactones, and (3 Lactams 181
23.4.2.1.1 Variation 1: With Alkenes, Enol Ethers, or Enecarbamates 181
23.4.2.1.2 Variation 2: With Aldehydes or Ketones 187
23.4.2.1.3 Variation 3: With Imines 189
23.4.2.2 Method 2: Lewis Acid Catalyzed [3,3] Sigmatropic Bellus Claisen
Rearrangements 194
23.5 Product Class 5: Sulfur and Selenium Substituted Ketenes
C. Palomo, J. M. Aizpurua, I. Canboa, and E. Gomez Bengoa
23.5 Product Class 5: Sulfur and Selenium Substituted Ketenes 199
23.5.1 Product Subclass 1: Sulfur Substituted Ketenes 199
23.5.1.1 Synthesis of Product Subclass 1 200
233.1.1.1 Method 1: Elimination Reactions of Carboxylic Acids and Their
Derivatives 200
233.1.1.1.1 Variation 1: Dehydration of Carboxylic Acids 200
233.1.1.1.2 Variation 2: Dehydrohalogenation of Acyl Halides 201
233.1.1.2 Method 2: Wolff Rearrangement of Diazo Compounds 203
233.1.1.2.1 Variation 1: Photochemical Wolff Rearrangement 203
233.1.1.2.2 Variation 2: Thermal Wolff Rearrangement 204
233.1.1.2.3 Variation 3: Metal Catalyzed Wolff Rearrangement 205
233.1.1.3 Method 3: Photolysis of Metal Carbene Complexes 205
233.1.1.4 Method 4: Fragmentation of Cyclobutene 1,2 diones 206
233.1.1.5 Methods 5: Miscellaneous Preparations 207
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 208
233.1.2.1 Methodi: [2+ 2] Cycloaddition Reactions 208
233.1.2.1.1 Variation 1: Reaction with Alkenes and Alkynes Leading to
Cyclobutanones and Cyclobutenones 208
233.1.2.1.2 Variation 2: Reaction with Imines Leading to P Lactams 212
233.1.2.2 Method 2: Formation of Allenes by Wittig Alkenation 214
233.2 Product Subclass 2: Selenium Substituted Ketenes 215
233.2.1 Synthesis of Product Subclass 2 215
233.2.1.1 Methodi: Dehydrohalogenation of Acyl Chlorides 215
233.2.1.2 Method 2: Reactions of Silver Ketenide 217
233.2.2 Applications of Product Subclass 2 in Organic Synthesis 217
233.2.2.1 Methodi: [2+ 2] Cycloaddition Reactions Leading to P Lactams 217
23.6 Product Class 6: Nitrogen and Phosphorus Substituted Ketenes
C. Palomo and J. M. Aizpurua
23.6 Product Class 6: Nitrogen and Phosphorus Substituted Ketenes 221
23.6.1 Product Subclass 1: Nitrogen Substituted Ketenes 221
23A1.1 Synthesis of Product Subclass 1 222
Table of Contents XV
23.6.1.1.1 Method 1: Elimination Reactions of a Amino Acids or Their Derivatives • 222
23.6.1.1.2 Method 2: Photolysis of Metal Carbene Complexes 224
23.6.1.2 Applications of Product Subclass 1 in Organic Synthesis 227
23.6.1.2.1 Method 1: Addition of Nitrogen or Oxygen Nucleophiles 227
23.6.1.2.2 Method 2: Cycloaddition Reactions with Alkenes Leading to
Cyclobutanones 229
23.6.1.2.3 Method 3: Cycloaddition Reactions with Imines or Hydrazones Leading
to P Lactams 230
23.6.1.2.4 Method 4: Lewis Acid Catalyzed Bellus Claisen Rearrangement 233
23.6.2 Product Subclass 2: Phosphorus Substituted Ketenes 234
23.6.2.1 Synthesis of Product Subclass 2 235
23.6.2.1.1 Method 1: Elimination Reactions of a Phosphorylcarboxylic Acid
Derivatives 235
23.6.2.1.2 Method 2: Wolff Rearrangement of ct Diazo P oxophosphonates 238
23.6.2.1.3 Method 3: Dehydroalkoxylation of ct Triarylphosphoranylidene Esters ¦•• 239
23.6.2.1.4 Method 4: Thermolysis of Phosphinoethynyl Ethers 240
23.7 Product Class 7: Alkylideneketenes
W. F. Austin, J. J. Kowalczyk, C. B. Dudley, and R. L. Danheiser
23.7 Product Class 7: Alkylideneketenes 245
23.7.1 Product Subclass 1: Substituted Methyleneketenes 245
23.7.1.1 Synthesis of Product Subclass 1 245
23.7.1.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 245
23.7.1.1.2 Method 2: Cycloreversion Reactions 246
23.7.1.1.3 Method 3: Thermolysis of Alkylidene Derivatives of Meldrum's Acid 247
23.7.1.1.4 Method 4: Dehalogenation of 2 Bromoacryloyl Chlorides 248
23.7.1.1.5 Method 5: Alkenation of Carbonyl Compounds with
Phosphorylideneketenes 248
23.7.1.2 Applications of Product Subclass 1 in Organic Synthesis 249
23.7.1.2.1 Method 1: [2+2] Cycloadditions Leading to Cyclobutane 1,3 diones
or a Alkylidene Substituted P Lactones 249
23.7.1.2.2 Method 2: Generation of Vinylidenes by Thermolysis or Photolysis 251
23.7.1.2.3 Method 3: Rearrangements Triggering Cyclization Reactions 252
23.7.2 Product Subclass 2: Carbon Suboxide 253
23.7.2.1 Synthesis of Product Subclass 2 253
23.7.2.1.1 Method 1: Elimination from Malonic Acid Derivatives 253
23.7.2.1.2 Method 2: Thermolysis of O,O Diacetyltartaric Anhydride 254
23.7.2.1.3 Method 3: Dehalogenation of Dibromomalonyl Chloride 254
23.7.2.2 Applications of Product Subclass 2 in Organic Synthesis 255
23.7.2.2.1 Method 1: Reaction with Nucleophiles Leading to Malonic Acid
Derivatives 255
23.7.2.2.2 Method 2: Generation of Oxovinylidene by Photolysis 256
XVI Table of Contents
23.8 Product Class 8: Cyanoketenes
H. W. Moore
23.8 Product Class 8: Cyanoketenes 259
23.8.1 Synthesis of Product Class 8 259
23.8.1.1 Method 1: Synthesis from 3 Azidocyclobut 3 ene 1,2 diones 260
23.8.1.2 Method 2: Synthesis from 2,5 and 2,6 Diazidobenzo 1,4 quinones 261
23.8.1.3 Method 3: Synthesis from 4 Azido 3 halo 5 methoxyfuran 2(5H) ones • • 263
23.8.1.4 Method 4: Synthesis of Cyano(trimethylsiloxy)ketene via a
Retro Diels Alder Reaction 266
23.8.1.5 Method 5: Synthesis of the Parent Cyanoketene 267
23.9 Product Class 9: Acylketenes
G. Kollenz and S. Ebner
23.9 Product Class 9: Acylketenes 271
23.9.1 Product Subclass 1: Monoalkanoylketenes and Formylketenes 272
23.9.1.1 Synthesis of Product Subclass 1 272
233.1.1.1 Method 1: Ruthenium(VIII) Oxide Oxidation of an Acylallene 272
23.9.1.1.2 Method 2: Dehydrochlorination of Acid Chlorides 272
23.9.1.1.3 Method 3: Flash Vacuum Pyrolysis 273
23.9.1.1.3.1 Variation 1: Of P Oxo Esters 273
23.9.1.1.3.2 Variation 2: Of 4H 1,3 Dioxin 4 onesand a 4H 1,3 Oxazin 4 one 273
233.1.1.3.3 Variation 3: Of Furan 2,3 diones 275
23.9.1.1.4 Method 4: Thermolysis Reactions 276
23.9.1.1.4.1 Variation 1: Of P Oxo Esters 276
233.1.1.4.2 Variation2: Of4H 1,3 Dioxin 4 ones 276
233.1.1.4.3 Variation 3: Of 5 Acyl 2,2 dimethyl 1,3 dioxane 4,6 diones 280
233.1.1.4.4 Variation 4: Of 4 Ethoxybut 3 yn 2 one 281
233.1.1.4.5 Variation 5: Of 2 Diazo 1,3 dicarbonyl Compounds 281
233.1.1.5 Method5: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 281
233.1.1.6 Method 6: [4 + 2] Dimerization of Dipivaloylketene 282
233.1.2 Applications of Product Subclass 1 in Organic Synthesis 283
233.1.2.1 Method 1: Cycloaddition Reactions 283
23.9.1.2.2 Method 2: Addition of Nucleophiles 284
233.2 Product Subclass 2: a (Oxomethylene)cycloalkanones 285
233.2.1 Synthesis of Product Subclass 2 285
23.9.2.1.1 Method 1: Dehydrochlorination of Acid Chlorides 285
233.2.1.2 Method 2: Flash Vacuum Pyrolysis of Cyclic P Oxo Esters 286
233.2.1.3 Method 3: Thermolysis Reactions 286
233.2.1.3.1 Variation 1: Of a Fused 4H 1,3 Dioxin 4 one 287
233.2.1.3.2 Variation 2: Of Cyclic 2 Diazo 1,3 diketones 288
233.2.1.4 Method 4: Photolysis of Cyclic 2 Diazo 1,3 diketones 290
Table of Contents XVII
233.3 Product Subclass 3: a (Oxomethylene)cycloalkenones 291
23.9.3.1 Synthesis of Product Subclass 3 291
23.9.3.1.1 Method 1: Thermolysis Reactions 291
23.9.3.1.1.1 Variation 1: Of Salicylic Acid Derivatives 291
23.9.3.U.2 Variation 2: Of Fused Furan 2,3 diones 292
23.9.3.1.1.3 Variation 3: Of 2 Diazo 1H indene 1,3(2H) dione 293
23.9.3.1.2 Method 2: Photolysis Reactions 293
23.9.3.1.2.1 Variation 1: Of 2 Phenyl 4H 1,3 benzodioxin 4 one 293
23.9.3.1.2.2 Variation 2: Of 2,3 Benzodioxin 1,4 dione 293
23.9.3.1.2.3 Variation 3: Of Fused 2 Diazo 1,3 diketones 294
23.9.3.1.3 Method 3: Addition of Alkynes to Carbon Suboxide 295
23.9.4 Product Subclass 4: a (Oxomethylene)heterocycloalkanones 296
23.9.4.1 Synthesis of Product Subclass 4 296
23.9.4.1.1 Methodi: Thermolysis of a Furo[3,4 d] 1,3 dioxinone 296
23.9.4.1.2 Method 2: Photolysis Reactions 297
23.9.4.1.2.1 Variation 1: Of 5 Diazo 2,2 dimethyl 1,3 dioxane 4,6 dione 297
23.9.4.1.2.2 Variation 2: Of 3 Diazo 1 methylquinoline 2,4(1H,3H) dione 298
23.9.5 Product Subclass 5: Dialkanoylketenes 299
233.5.1 Synthesis of Product Subclass 5 299
23.9.5.1.1 Method 1: Flash Vacuum Pyrolysisof 5 tert Butyl 4 pivaloylfuran 2,3
dione 299
233.5.2 Applications of Product Subclass 5 in Organic Synthesis 300
233.5.2.1 Methodi: Cycloaddition Reactions 300
233.5.2.2 Method 2: Addition of Nudeophiles 301
233.6 Product Subclass 6: Monoaroylketenes 302
233.6.1 Synthesis of Product Subclass 6 302
233.6.1.1 Methodi: Thermolysis Reactions 302
233.6.1.1.1 Variation 1: Of P Oxo Esters 302
233.6.1.1.2 Variation2: Of 4H 1,3 Dioxin 4 ones and 1,3 Dioxane 4,6 diones 302
233.6.1.1.3 Variation 3: Of Furan 2,3 diones 303
233.6.1.1.4 Variation 4: Of 2 Diazo 1,3 diketones 305
23.9.6.1.2 Method 2: Photolysis Reactions 310
23.9.6.1.2.1 Variation 1: Of 5 Phenylfuran 2,3 dione 310
23.9.6.1.2.2 Variation 2: Of 2 Diazo 1,3 diketones 310
233.6.1.2.3 Variation 3: Of a Mesoionic Compound 311
233.7 Product Subclass 7: Diaroylketenes 311
233.7.1 Synthesis of Product Subclass 7 311
233.7.1.1 Methodi: Flash Vacuum Pyrolysis of 4 Benzoyl 5 phenylfuran 2,3 dione 311
23.9.7.1.2 Method 2: Thermolysis of 4 Benzoyl 5 phenylfuran 2,3 dione 312
233.8 Product Subclass 8: Carboxyketenes 314
233.8.1 Synthesis of Product Subclass 8 314
XVIII Table of Contents
23.9.8.1.1 Method 1: Flash Vacuum Pyrolysis of 5 Alkylidene 2,2 dimethyl 1,3
dioxane 4,6 diones 314
23.9.9 Product Subclass 9: (Alkoxycarbonyl)ketenes 315
23.9.9.1 Synthesis of Product Subclass 9 315
23.9.9.1.1 Method 1: Dehydrochlorination of Acid Chlorides 315
23.9.9.1.2 Method 2: Thermolysis Reactions 316
23.9.9.1.2.1 Variation 1: Of Acid Derivatives 316
23.9.9.1.2.2 Variation 2: Of 6 Methoxy 4H 1,3 dioxin 4 ones 317
23.9.9.1.2.3 Variation 3: Of a Pyrro!o[1,2 o]quinoxalinetrione 317
23.9.9.1.2.4 Variation 4: Of Dimethyl Diazomalonate 317
23.9.9.1.3 Method 3: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 318
23.9.9.2 Applications of Product Subclass 9 in Organic Synthesis 318
23.9.9.2.1 Method 1: Cycloaddition Reactions 318
23.9.9.2.2 Method 2: Addition of Nucleophiles 319
233.10 Product Subclass 10: Acyl(alkoxycarbonyl)ketenes 319
23.9.10.1 Synthesis of Product Subclass 10 319
23.9.10.1.1 Method 1: Flash Vacuum Pyrolysis of Methyl 2 rert Butyl 4,5 dioxo 4,5
dihydrofuran 3 carboxylate 319
23.9.10.1.2 Method 2: Thermolysis Reactions 320
23.9.10.1.2.1 Variations Of4H 1,3 Dioxin 4 ones 320
233.10.1.2.2 Variation 2: Of Ethyl 4,5 Dioxo 2 phenyl 4,5 dihydrofuran 3 carboxylate ¦ 321
233.10.2 Applications of Product Subclass 10 in Organic Synthesis 322
23.9.10.2.1 Method 1: Cycloaddition Reactions 322
233.10.2.2 Method 2: Addition of Amines 323
233.11 Product Subclass 11: Bis(alkoxycarbonyl)ketenes 324
233.11.1 Synthesis of Product Subclass 11 324
233.11.1.1 Method 1: Thermolysis of 2 Diazo 3 oxosuccinates 324
233.11.1.2 Method 2: Photolysis of 2 Diazo 1,3 dicarbonyl Compounds 324
233.11.1.3 Method 3: Reaction of Tetraethoxyallene with Phosgene 325
233.11.2 Applications of Product Subclass 11 in Organic Synthesis 325
233.11.2.1 Method 1: Preparation of Allenetetracarboxylates 325
23.9.11.2.2 Method 2: Cycloaddition Reactions 326
233.11.2.3 Method 3: Ring Transformations of Five Membered Heterocycles 326
233.12 Product Subclass 12: (Chlorocarbonyl)ketenes 327
233.12.1 Synthesis of Product Subclass 12 327
233.12.1.1 Method 1: Dehydrochlorination of Malonyl Chlorides 327
233.12.2 Applications of Product Subclass 12 in Organic Synthesis 329
233.12.2.1 Method 1: Cycloaddition Reactions 329
233.12.2.2 Method 2: Condensation Reactions 330
233.13 Product Subclass 13: Fluorinated Acylketenes 333
233.13.1 Synthesis of Product Subclass 13 333
Table of Contents XIX
23.9.13.1.1 Method 1: Thermolysis Reactions 333
23.9.13.1.1.1 Variation 1: Of (Trifluoromethyl)malonic Acid Derivatives 333
23.9.13.1.1.2 Variation 2: Of Fluorinated 4H 1,3 Dioxin 4 ones 334
23.9.13.1.2 Method 2: Transformation of Fluorinated Alkenes and Alkynes 335
23.9.13.1.2.1 Variation 1: By Reaction with Sulfur Trioxide 335
23.9.13.1.2.2 Variation 2: With Lewis Acid Catalysis 336
23.9.13.1.3 Method 3: Photolysis of Methyl 2 Diazo 4,4,4 trifluoroacetoacetate — 337
23.9.13.2 Applications of Product Subclass 13 in Organic Synthesis 337
23.9.13.2.1 Method 1: Cycloaddition Reactions 337
23.9.13.2.2 Method 2: Electrophilic Substitution Reactions 338
23.9.13.2.3 Method 3: Addition of Nucleophiles 339
233.14 Product Subclass 14: Acyl(phosphoryl)ketenes and
Acyl(trialkylmetal)ketenes 341
23.9.14.1 Synthesis of Product Subclass 14 341
23.9.14.1.1 Method 1: Transformation of [Dialkoxy(bromo)phosphoranylidene]malo
nates 341
23.9.14.1.2 Method 2: Photolysis or Thermolysis of Methyl 2 Diazo 3 (diisoprop
oxyphosphoryl) 3 oxopropanoate 341
23.9.14.1.3 Method 3: Addition of Organometallic Compounds to Carbon Suboxide 341
23.9.14.1.4 Method 4: Transformation of Functionalized Ethoxyacetylenes 342
23.10 Product Class 10: Imidoylketenes
C. Kollenz
23.10 Product Class 10: Imidoylketenes 351
23.10.1 Product Subclass 1: N Unsubstituted and N Alkyl Substituted
Imidoylketenes 351
23.10.1.1 Synthesis of Product Subclass 1 351
23.10.1.1.1 Method 1: Pyrolysis Reactions 352
23.10.1.1.1.1 Variation 1: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 352
23.10.1.1.1.2 Variation 2: Flash Vacuum Pyrolysis of Pyrrole 2,3 diones 353
23.10.1.1.1.3 Variation 3: Thermolysis of 3 Aminoacrylates 353
23.10.1.1.2 Method 2: Reaction of 1 Aminopyridinium Iodide with
2,3 Diphenylcycloprop 2 en 1 one 354
23.10.1.1.3 Method 3: Extrusion of Sulfur from lsothiazol 5(2H) ones 355
23.10.2 Product Subclass 2: (At Acylimidoyl)ketenes 356
23.10.2.1 Synthesis of Product Subclass 2 356
23.10.2.1.1 Method 1: Pyrolysis of 3 (Acylamino)acrylates 356
23.10.2.1.2 Method 2: Reaction of Pyridinium Ylides with
2,3 Diphenylcycloprop 2 en 1 one 357
23.10.2.1.3 Method 3: Reaction of Di tert butoxyacetylene with Benzoyl Isocyanate • 357
23.103 Product Subclass 3: (W Arylimidoyl)ketenes 358
23.io.3i Synthesis of Product Subclass 3 358
23.10.3/u Method 1: Thermolysis Reactions 359
XX Table of Contents
23.10.3.1.1.1 Variation 1: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 359
23.10.3.1.1.2 Variation 2: Pyrolysis of 1 Aryl 1H pyrrole 2,3 diones 360
23.10.3.1.1.3 Variation 3: Flash Vacuum Pyrolysis of 1 Aryl 1H 1,2,3 triazoles 362
23.10.3.1.1.4 Variation 4: Thermolysis of N Arylketenimines 363
23.10.3.1.1.5 Variation 5: Thermolysis of Mesoionic Compounds 364
23.10.3.1.2 Method 2: Extrusion of Sulfur from lsothiazol 5(2H) ones 364
23.10.4 Product Subclass 4: A/Hetaryl Substituted Imidoylketenes 365
23.10.4.1 Synthesis of Product Subclass 4 365
23.10.4.1.1 Method 1: Pyrolysis Reactions 365
23.10.4.1.1.1 Variation 1: Flash Vacuum Pyrolysis of 1 (1H Pyrazol 5 yl) 1H 1,2,3
triazoles 365
23.10.4.1.1.2 Variation 2: Flash Vacuum Pyrolysis of Meldrum's Acid Derivatives 366
23.10.4.1.2 Method 2: Lithiation of lsoxazol 5(2H) ones 366
23.10.5 Product Subclass 5: Acyl(imidoyl)ketenes 367
23.10.5.1 Synthesis of Product Subclass 5 367
23.10.5.1.1 Method 1: Thermolysis Reactions of Pyrrole 2,3 diones and
Furan 2,3 diones 367
23.10.5.1.1.1 Variation 1: In the Solid State 367
23.10.5.1.1.2 Variation 2: In Solution 368
23.10.6 Product Subclass 6: N Unsubstituted 6 (0xomethylene)cyclohexa
2.4 dien l imines 372
23.10.6.1 Synthesis of Product Subclass 6 372
23.10.6.1.1 Method 1: Thermolysis of 1,2,3 Benzotriazin 4(3H) ones 372
23.10.6.1.2 Method2: Reactions of 3,2,1 Benzoxathiazin 4(1 H) one 2 Oxide 373
23.10.7 Product Subclass 7: N Substituted 6 (0xomethylene)cyclohexa
2,4 dien 1 imines 374
23.10.7.1 Synthesis of Product Subclass 7 374
23.10.7.1.1 Method 1: Photolysis Reactions of 1,2,3 Benzotriazin 4(3H) ones 375
23.10.7.1.2 Method 2: Thermolysis Reactions 376
23.10.7.1.2.1 Variation 1: Of a 3,2,1 Benzoxathiazin 4(1H) one 2 Oxide 376
23.10.7.1.2.2 Variation2: Of2,1 Benzisothiazol 3(1H) ones 377
23.10.7.1.2.3 Variation 3: Of 1 Phenyl 1H indole 2,3 dione 377
23.10.7.1.3 Method 3: Ring Opening of 2,1 Benzisoxazol 1 ium Salts 377
23.11 Product Class 11: Alk 1 ynylketenes
H. W. Moore
23.11 Product Class 11: Alk 1 ynylketenes 381
23.11.1 Synthesis of Product Class 11 381
23.11.1.1 Method 1: Retro Diels Alder Reactions 381
23.11.1.2 Method 2: Thermolysis of 1 Alkoxyalk 1 ynes 384
23.11.1.3 Method 3: Alk 1 ynyl(cyano)ketenes from 2,5 Di(alk 1 ynyl) 3,6
diazidobenzo 1.4 quinones 385
23.11.1.4 Methods 4: Additional Methods for the Generation of Alk 1 ynylketenes • 389
Table of Contents XXI
23.12 Product Class 12: Aryl and Hetarylketenes
T. T. Tidwell
23.12 Product Class 12: Aryl and Hetarylketenes 391
23.12.1 Product Subclass 1: Monoarylketenes 392
23.12.11 Synthesis of Product Subclass 1 393
23.12.1.1.1 Method 1: Monoarylketenes by Dehydration of Arylacetic Acids 393
23.12.1.1.2 Method 2: Monoarylketenes from Arylacetic Anhydrides 393
23.12.1.1.2.1 Variation 1: Arylketene by Decarboxylation of Arylmalonic Acids 394
23.12.1.1.3 Method 3: Monoarylketenes from Arylacetate Esters 394
23.12.1.1.4 Method 4: Monoarylketenes by Dehydrohalogenation of Arylacetyl
Chlorides 395
23.12.1.1.4.1 Variation 1: Monoarylketenes by Dehydrochlorination Using a Shuttle
Procedure with a Kinetic Base and a Stoichiometric Base 396
23.12.1.1.5 Method 5: Monoarylketenes by Dehalogenation of Arylhaloacetyl Halides 399
23.12.1.1.6 Method 6: Monoarylketenes by Wolff Rearrangement of a Diazo Ketones 400
23.12.1.1.6.1 Variation 1: Metal Catalyzed Wolff Rearrangement 401
23.12.1.1.6.2 Variation 2: Monoarylketenes by Microwave and Ultrasound Enhanced
Wolff Rearrangement 403
23.12.1.1.6.3 Variation 3: Monoarylketenes by Photochemical Wolff Rearrangement ••• 404
23.12.1.1.6.4 Variation 4: Phenylketene by Wolff Type Rearrangement of a Sulfur Ylide 405
23.12.1.1.7 Method 7: Monoarylketenes from Ynols and Ynolates 405
23.12.1.1.8 Method 8: Monoarylketenes by Oxidation of Arylacetylenes 406
23.12.1.1.8.1 Variation 1: Monoarylketenes by Oxidation of Lithium Arylacetylides 407
23.12.1.1.8.2 Variation 2: Monoarylketenes by Ruthenium Catalyzed Alkyne
Oxygenation 408
23.12.1.1.9 Method 9: Monoarylketenes from Metal Carbene Complexes 409
23.12.1.2 Applications of Product Subclass 1 in Organic Synthesis 410
23.12.1.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to
Monoarylketenes 410
23.12.1.2.2 Method 2: Ketones and Vinyl Ethers by Addition of Carbon Electrophiles 410
23.12.1.2.3 Method 3: /V Aroyloxyamines by Aminoxyl Radical Addition to
Monoarylketenes 411
23.12.1.2.4 Method 4: Cyclobutanones by [2+2] Cycloaddition with Alkenes and
Dienes 412
23.12.1.2.5 Method 5: Cyclobutenones by [2 + 2] Cycloaddition of Monoarylketenes
with Alkynes 414
23.12.1.2.6 Method 6: p" Lactams by [2 + 2] Cycloaddition of Monoarylketenes with
Imines 416
23.12.1.2.6.1 Variation 1: Pyrimidinones by [4+2] Cycloaddition of Monoarylketenes
with 1,3 Diazabuta 1,3 dienes 418
23.12.1.2.7 Method 7: 2 Arylacetate Derivatives by [4 + 2] Cycloaddition of
o Chloranil with Ketene Enolates 419
23.12.1.2.8 Method 8: Carbene Formation by Decarbonylation of Monoarylketenes • 419
23.12.2 Product Subclass 2: Alkyl(aryl) and Aryl(vlnyl)ketenes 420
23.12.2.1 Synthesis of Product Subclass 2 421
XXII Table of Contents
23.12.2.1.1 Method 1: Alkyl(aryl)ketenes by Elimination from 2 Arylalkanoate Esters 421
23.12.2.1.2 Method 2: Alkyl(aryl)ketenes by Dehydrohalogenation of 2 Arylalkanoyl
Chlorides 423
23.12.2.1.3 Method 3: Alkyl(aryl)ketenes by Dehalogenation of
2 Aryl 2 haloalkanoyl Halides 423
23.12.2.1.4 Method 4: Alkyl(aryl)ketenes by Wolff Rearrangement of a Diazo
Ketones 424
23.12.2.1.5 Method 5: Alkyl(aryl)ketenes by Decarboxylation of Malonic Acids 425
23.12.2.1.6 Method 6: Aryl(vinyl)ketenes by Cyclobutenone Ring Opening 425
23.12.2.1.7 Method 7: Aryl(vinyl)ketenes from Metal Carbene Complexes 426
23.12.2.1.8 Method 8: Alkyl(aryl)ketenes by [4+2] Cycloadditions of Cyclic Diazines 427
23.12.2.2 Applications of Product Subclass 2 in Organic Synthesis 428
23.12.2.2.1 Method 1: 2 Arylalkanoic Acid Derivatives by Stereoselective
Esterification of Alkyl(aryl)ketenes 428
23.12.2.2.1.1 Variation 1: Chiral 2 Arylalkanoate Esters by Catalytic Stereoselective
Addition of Methanol to Alkyl(aryl)ketenes 431
23.12.2.2.1.2 Variation 2: Chiral 2 Arylalkanoate Enol Esters by Catalytic Stereoselective
Esterification of Alkyl(aryl)ketenes with Aldehydes 433
23.12.2.2.1.3 Variation 3: Chiral 2 Arylalkanamides by Stereoselective Amination of
Alkyl(aryl)ketenes 434
23.12.2.2.2 Method 2: Ketones and Vinyl Esters and Ethers by Addition of Carbon
Nucleophiles to Ethyl(phenyl)ketene 436
23.12.2.2.3 Method 3: Divinyl Ketone Formation by Iridium Alkyne Complex
Addition to Methyl(phenyl)ketene with Double C—H
Activation 438
23.12.2.2.4 Method 4: Lactones and Cycloalkanones by Electrophilic Addition to
Alkyl(aryl)ketenes 438
23.12.2.2.5 Method 5: Allenyl Ketones and Esters by Wittig Type Reactions of
Alkyl(aryl)ketenes 439
23.12.2.2.6 Method 6: Cyclobutanones by [2 + 2] Cycloaddition of
Methyl(phenyl)ketene with Alkenes and Dienes 440
23.12.2.2.6.1 Variation 1: Cyclobutanones by Intramolecular [2 + 2] Cycloaddition of
Aryl(pent 4 enyl)ketenes 441
23.12.2.2.7 Method 7: Naphthol Formation by Intramolecular Cyclization of an
Alkyl(aryl)ketene with an Alkynyl Group 441
23.12.2.2.8 Method 8: p Lactone Formation by Intramolecular Cycloaddition of an
Alkyl(aryl)ketene with a Carbonyl Group 442
23.12.2.2.9 Method 9: Succinic Anhydrides by Oxidation of Alkyl(aryl)ketenes 442
23.12.2.2.10 Method 10: Aminoxyl Radical Substituted Polymers from Alkyl(aryl)ke
tenes 442
23.12.3 Product Subclass 3: Diarylketenes 443
23.12.3.1 Synthesis of Product Subclass 3 444
23.12.3.1.1 Method 1: Diarylketenes by Dehydration of Diarylacetic Acids 444
23.12.31.2 Method 2: Diarylketenes by Dehydrochlorination of Diarylacetyl
Chlorides 445
23.123.1.3 Method 3: Diarylketenes by Dehalogenation of Diarylhaloacetyl Halides 446
Table of Contents XXIII
23.12.3.1.4 Method 4: Diarylketenes by Pyrolysisof Diarylketene Acetals 448
23.12.3.1.5 Method 5: Diarylketenes by Wolff Rearrangement of ce Diazo Ketones •¦ 448
23.12.3.1.5.1 Variation 1: Diarylketenes by Photochemical Wolff Rearrangement of
a Diazo Ketones 449
23.12.3.1.6 Method 6: Diarylketenes by Oxidation of Diarylacetylenes 449
23.12.3.2 Applications of Product Subclass 3 in Organic Synthesis 450
23.12.3.2.1 Method 1: Diarylacetic Acid Derivatives by Nucleophilic Additions to
Diarylketenes 450
23.12.3.2.2 Method 2: Alcohols, Aldehydes, Ketones, and Enol Derivatives by
Addition of Hydrogen, Carbon, and Silicon Nucleophiles
and Electrophiles to Diarylketenes 450
23.12.3.2.2.1 Variation 1: Cyclopropanones by Diazoalkane Addition to Diarylketenes ¦• 453
23.12.3.2.3 Method 3: Aminoxy Esters from Aminoxyl Radical Addition to
Diarylketenes 454
23.12.3.2.4 Method 4: Allenes by Wittig Reactions 454
23.12.3.2.4.1 Variation 1: Ketenimines by Aza Wittig Reaction of Diarylketenes 455
23.12.3.2.5 Method 5: Cyclobutanones and Other Products by Cycloaddition
Reactions with Alkenes and Dienes 455
23.12.3.2.6 Method 6: [2 + 2] and [2 + 2 + 2] Cycloadditions with Alk 1 ynyl Ethers •¦• 459
23.12.3.2.7 Method 7: p Lactams by [2 + 2] Cycloaddition with Imines 459
23.12.3.2.7.1 Variation 1: S Lactams by [4+2] Cycloaddition with Chiral
2 Vinyl 4,5 dihydrothiazoles 461
23.12.3.2.8 Method 8: P Lactones by [2 + 2] Cycloaddition with Carbonyl Groups— 462
23.12.3.2.8.1 Variation 1: y Lactone Formation by Diarylketene Reaction with Carbonyl
Compounds 463
23.12.3.2.9 Method 9: Polyesters by Oxidation of Diarylketenes 463
23.12.3.2.10 Method 10: Diarylacetylenes by Deoxygenation of Diarylketenes 464
23.12.3.2.11 Method 11: Carbenes and Carbocations by Decarbonylation of
Diarylketenes 464
23.12.4 Product Subclass 4: Fulvenones 465
23.12.4.1 Synthesis of Product Subclass 4 466
23.12.4.1.1 Method 1: Fulvenones by Elimination from Esters 466
23.12.4.1.2 Method 2: Fulvenones by Dehydrochlorination of Acyl Chlorides 466
23.12.4.1.3 Method 3: Fulvenones by Dehalogenation of 2 Haloacyl Halides 467
23.12.4.1.4 Method 4: Fulvenones by Wolff Rearrangement of a Diazo Ketones — 468
23.12.4.1.4.1 Variation 1: Azafulvenones by Wolff Rearrangement and Other Routes • • ¦ 470
23.12.4.1.4.2 Variation 2: Pentafulvenone by Photochemical Wolff like Rearrangement
of 2 Halophenols 471
23.12.4.2 Applications of Product Subclass 4 in Organic Synthesis 472
23.12.4.2.1 Method 1: Pyridinium Zwitterions from Pentafulvenones 472
23.12.4.2.2 Method 2: Cyclobutanones by [2 + 2] Cycloaddition with Alkenes and
Dienes 472
2312.5 Product Subclass 5: Hetarylketenes 473
23.12.5.1 Synthesis of Product Subclass 5 473
23.12.5.1.1 Method 1: Hetarylketenes by Ester Elimination of Hetarylacetates 473
XXIV Table of Contents
23.12.5.1.2 Method 2: Hetarylketenes by Dehydrochlorination of Hetarylacetyl
Chlorides 473
23.12.5.1.2.1 Variation 1: Hetarylketenes by Dehydrochlorination Using a Shuttle
Procedure with a Kinetic Base, and a Stoichiometric Base — 475
23.12.5.1.3 Method 3: Hetarylketenes by Thermal Decarbonylation of
Furan 2,3 diones 475
23.12.5.1.4 Method 4: Hetarylketenes by Wolff Rearrangement of a Diazo Ketones • 476
23.12.5.1.4.1 Variation 1: Hetarylketenes by Rhodium Catalyzed Wolff Rearrangement
of a Diazo Ketones 478
23.12.5.1.4.2 Variation 2: Hetarylketenes by Wolff Rearrangement and
[2+2] Cycloaddition with Alkynes 478
23.12.5.1.4.3 Variation 3: Hetarylketenes by Wolff like Rearrangements of Triazoles
and Other Substrates 479
23.12.5.1.5 Method 5: Hetarylketenes by Carbene Carbonylation 481
23.12.5.1.6 Method 6: Hetarylketenes from Chromium Carbene Complexes 481
23.12.5.2 Applications of Product Subclass 5 in Organic Synthesis 482
23.12.5.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to
Hetarylketenes 482
23.12.5.2.2 Method 2: lmidazo[4,5 c]isoxazole Formation by Cyclization of
Hetarylketenes 482
23.12.6 Product Subclass 6: Ferrocenylketenes 483
23.i2.6i Synthesis of Product Subclass 6 483
23.12.6.1.1 Method 1: Ferrocenylketene by Activation of Ferrocenylacetic Acid 483
23.12.6.1.2 Method 2: Ferrocenylketenes by Wolff Rearrangement of a Diazo
Ketones 485
23.13 Product Class 13: Alkenylketenes
R. L Danheiser, C. B. Dudley, and W. F. Austin
23.13 Product Class 13: Alkenylketenes 493
23.13.1 Product Subclass 1: Vinylketenes 494
23.13.1.1 Synthesis of Product Subclass 1 494
23.13.1.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 494
23.13.1.1.2 Method 2: Wolff Rearrangement of a' Diazo a,p unsaturated Ketones •¦ 498
23.13.1.1.3 Method 3: Electrocyclic Ring Opening of Cyclobutenones 501
23.13.1.2 Applications of Product Subclass 1 in Organic Synthesis 504
23.13.1.2.1 Method 1: [2 + 2] Cycloadditions Leading to 4 Alkenylcyclobutanones ¦¦• 506
23.13.1.2.1.1 Variation 1: Intermolecular Cycloadditions 507
23.13.1.2.1.2 Variation 2: Intramolecular Cycloadditions 512
23.13.1.2.2 Method 2: [2+2] Cycloadditions Leading to P Lactams 520
23.13.2 Product Subclass 2:1,3 Dienylketenes and (2 Arylvinyl)ketenes 522
23.13.2.1 Synthesis of Product Subclass 2 522
23.13.2.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 525
23.13.2.1.2 Method 2: Wolff Rearrangement of 1,3 Dienyl a' Diazo Ketones 526
Table of Contents XXV
23.13.2.1.3 Method 3: Electrocyclic Ring Opening of Cyclobutenones 527
23.13.2.1.3.1 Variation 1: Electrocyclic Ring Opening of 4 Alkenyl and
4 Arylcyclobutenones 528
23.13.2.1.3.2 Variation 2: Electrocyclic Ring Opening of 2 (1,3 Dienyl)cyclobutenones
and 2 (2 Arylvinyl)cyclobutenones 530
23.13.2.1.4 Method 4: Electrocyclic Ring Opening of 6,6 Disubstituted
Cyclohexa 2,5 dien 1 ones 531
23.13.2.2 Applications of Product Subclass 2 in Organic Synthesis 533
23.13.2.2.1 Method 1: Six Electron Electrocyclizations Leading to Phenols 533
23.13.2.2.1.1 Variation 1: Of Ketenes from the Elimination of Carboxylic Acid Derivatives 534
23.13.2.2.1.2 Variation 2: Of Ketenes Generated by the Electrocyclic Ring Opening
of Cyclobutenones 539
23.13.2.2.1.3 Variation 3: Of Ketenes Generated by Electrocyclic Ring Opening
of 4 Hydroxycyclobutenones 547
23.13.3 Product Subclass 3: Alk 1 en 3 ynylketenes 555
23.13.3.1 Synthesis of Product Subclass 3 556
23.13.3.1.1 Method 1: Elimination from Carboxylic Acid Derivatives 556
23.13.3.1.2 Method 2: Wolff Rearrangement of Diazo Ketones 557
23.13.3.1.3 Method 3: Electrocyclic Ring Opening of 4 Alkynylcyclobutenones 558
23.13.3.2 Applications of Product Subclass 3 in Organic Synthesis 559
23.13.3.2.1 Method 1: Cyclizations Leading to Quinones 559
23.14 Product Class 14: Alkyl and Cycloalkylketenes
T. T. Tidwell
23.14 Product Class 14: Alkyl and Cycloalkylketenes 569
23.14.1 Product Subclass 1: Monoalkylketenes 571
23.14.1.1 Synthesis of Product Subclass 1 571
23.14.1.1.1 Method 1: Dehydration of Alkanoic Acids 572
23.14.1.1.1.1 Variation 1: Dehydration of Carboxylic Acids Using Mukaiyama's Reagent 572
23.14.1.1.2 Method 2: Pyrolysis of Alkanoic Anhydrides 574
23.14.1.1.2.1 Variation 1: From Alkanoic Anhydrides under Perkin Conditions 575
23.14.1.1.3 Method 3: Michael Addition and Elimination Reaction of Alkanoate Esters 575
23.14.1.1.3.1 Variation 1: Ester Pyrolysis 576
23.14.1.1.4 Method 4: Dehydrohalogenation of Alkanoyl Chlorides 577
23.14.1.1.4.1 Variation 1: Dehydrochlorination Using a Shuttle Procedure with a Kinetic
Base and a Stoichiometric Base 577
23.14.1.1.5 Method5: Synthesis from Cycloalkanones and Hexa 1,5 dien 3 ones •¦• 579
23.14.1.1.5.1 Variation 1: Photolysis of Cyclobutanones 581
23.14.1.1.5.2 Variation 2: Photolysis of Cyclohexanones 582
23.14.1.1.5.3 Variation3: Photolysis of Hexa 1,5 dien 3 ones 583
23.14.1.1.6 Method 6: Dehalogenation of 2 Haloalkanoyl Halides 583
23.14.1.1.7 Method 7: Wolff Rearrangement of Diazo Ketones 585
23.14.1.1.7.1 Variation 1: Metal Catalyzed Wolff Rearrangement 585
23.14.1.1.7.2 Variation 2: Ultrasound Assisted Wolff Rearrangement 586
XXVI Table of Contents ™_
23.14.1.1.7.3 Variation 3: Microwave Enhanced Wolff Rearrangement 587
23.14.1.1.7.4 Variation 4: Photochemical Wolff Rearrangement 587
23.14.1.1.8 Method 8: Thermolysis of Alkynyl Ethers 588
23.14.1.1.9 Method 9: Synthesis from Ynolates (The Kowalski Homologation) 590
23.14.1.2 Applications of Product Subclass 1 in Organic Synthesis 590
23.14.1.2.1 Method 1: Allenyl Esters by Wittig Reactions of Monoalkylketenes 590
23.14.1.2.2 Method 2: Alkanoic Acid Derivatives by Addition of Heteroatom
Nucleophiles to Monoalkylketenes 592
23.14.1.2.2.1 Variation 1: Alkanoic Acid Derivatives by the Arndt Eistert Chain
Elongation 592
23.14.1.2.2.2 Variation 2: P Amino Acid Derivatives by the Arndt Eistert Reaction 593
23.14.1.2.2.3 Variation 3: P Amino Acid Esters by Kowalski Homologation of Esters— 595
23.14.1.2.2.4 Variation 4: Aldols via Boron Enolates from the Addition of Sulfur
Nucleophiles to Monoalkylketenes 596
23.14.1.2.2.5 Variation 5: y Lactams by Intramolecular Cyclization of Monoalkylketenes
with Nitrogen Nucleophiles 597
23.14.1.2.2.6 Variation 6: Amides by Allylic Amine Addition and Aza Claisen
Rearrangement 598
23.14.1.2.3 Method 3: 2 Halo Esters by Addition of Electrophilic Halogenating
Agents to Monoalkylketenes 599
23.14.1.2.4 Method 4: Ketones and Vinyl Ethers by Addition of Carbon Nucleophiles
to Monoalkylketenes 600
23.14.1.2.5 Method 5: Trifluoromethyl Ketones and Oxo Esters by Acylation of
Monoalkylketenes with Trifluoroacetic Anhydride 601
23.14.1.2.6 Method 6: 3 Methylene P lactones by Dimerization of Monoalkylketenes 601
23.14.1.2.7 Method 7: Cyclobutanones by [2 + 2] Cycloaddition of Monoalkylketenes
with Alkenes and Dienes 603
23.14.1.2.7.1 Variation 1: Polycyclic Ketones by Intramolecular [2 + 2] Cycloaddition of
Monoalkylketenes with Alkenyl Groups 606
23.14.1.2.8 Method 8: P Lactams by [2 + 2] Cycloaddition of Monoalkylketenes with
Imines 608
23.14.1.2.9 Method 9: fRactones by [2 + 2] Cycloaddition of Monoalkylketenes with
Aldehydes 609
23.14.1.2.10 Method 10: y Lactones by Intramolecular [3 + 2] Cyclization of Ketenes to
Cyclobutanones 611
23.14.1.2.11 Method 11: Cydopropanones by [2 + 1] Cycloaddition of
Monoalkylketenes with Diazoalkanes 612
23.14.1.2.12 Method 12: 2 Hydroxyalkanoates by [4+2] Cycloaddition of o Chloranil
with Ketene Enolates 613
23.14.2 Product Subclass 2: Dialkylketenes and (Oxomethylene)cycloalkanes ¦¦¦• 613
23.14.2.1 Synthesis of Product Subclass 2 614
23.14.2.1.1 Method 1: Dehydration of Dialkylalkanoic Acids 614
23.14.2.1.2 Method 2: Pyrolysis of 2 Alkylalkanoic Anhydrides 615
23.14.2.1.2.1 Variation 1: Decarboxylation of Dialkylmalonic Anhydrides 616
23.14.2.1.3 Method 3: Elimination Reactions of 2 Alkylalkanoate Ester Enolates 617
Table of Contents XXVII
23.14.2.1.3.1 Variation 1: Elimination from Ester Enolates Formed by Michael Addition
to Acrylates 619
23.14.2.1.4 Method 4: Dehydrochlorination of 2 Alkylalkanoyl Halides 620
23.14.2.1.5 Method 5: Pyrolysis of Ketene Dimers 625
23.14.2.1.6 Method 6: Dehalogenation of 2 Haloalkanoyl Halides 628
23.14.2.1.6.1 Variation 1: Dehalogenation of 2 Haloalkanoyl Halides with Other Metals 629
23.14.2.1.7 Method 7: Wolff Rearrangement of Diazo Ketones 630
23.14.2.1.7.1 Variation 1: Photochemical Wolff Rearrangement of Diazo Ketones 632
23.14.2.1.7.2 Variation 2: Ultrasound Enhanced Wolff Rearrangement 634
23.14.2.1.7.3 Variation 3: Photochemical Wolff Rearrangement of a Oxo Ketenes 635
23.14.2.1.8 Method 8: Oxygenation of a Dialkylthioketene 635
23.14.2.2 Applications of Product Subclass 2 in Organic Synthesis 635
23.14.2.2.1 Method 1: Carbenes by Decarbonylation of Dialkylketenes 635
23.14.2.2.2 Method 2: Carboxylic Acid Derivatives by Nucleophilic Addition to
Dialkylketenes 636
23.14.2.2.2.1 Variation 1: Carboxylic Anhydrides and Derivatives by Electrophilic
Addition to Dialkylketenes 637
23.14.2.2.2.2 Variation 2: Esters and Free Radicals by Radical Addition to Dialkylketenes 638
23.14.2.2.3 Method 3: Ketones and Vinyl Ethers by Addition of Carbon Nucleophiles
to Dialkylketenes 639
23.14.2.2.4 Method 4: Cyclobutane 1,3 diones by Dimerization of Dialkylketenes ¦•• 642
23.14.2.2.4.1 Variation 1: Cyclobutane 1,3 diones by Mixed Dimerization of
Dialkylketenes with tert Butyl(cyano)ketene 643
23.14.2.2.5 Method 5: Cyclobutanones and Cyclobutenones by [2 + 2] Cycloaddition
of Dialkylketenes with Alkenes, Dienes, Allenes, or Alkynes • • 644
23.14.2.2.5.1 Variation 1: Bicyclo[n.2.0]alkanones by Intramolecular [2 + 2] Cycloaddition
with Alkenyl Groups 649
23.14.2.2.6 Method 6: f5 Lactams by [2 + 2] Cycloaddition of Dialkylketenes with
Imines 653
23.14.2.2.6.1 Variation 1: Malonimides by [2 + 2] Cycloaddition of Dialkylketenes with
Isocyanates 654
23.14.2.2.7 Method 7: p Lactones by [2 + 2] Cycloaddition of Dialkylketenes with
Aldehydes 655
23.14.2.2.7.1 Variation 1: p Lactones by Asymmetric [2 + 2] Cycloaddition of
Dimethylketene with Chiral Aldehydes 655
23.14.2.2.8 Method 8: Cyclopropanones by [2 +1 ] Cycloaddition of Dialkylketenes
with Diazoalkanes 656
23.14.2.2.9 Method 9: Polymerization of Dialkylketenes 657
23.14.3 Product Subclass 3: Cyclopropylketene, (Cydoprop 2 enyl)ketene,
and Oxiranylketene 658
23.14.3.1 Synthesis of Product Subclass 3 658
23.14.3.M Method 1: Elimination from Cyclopropylacetates 658
23.14.3.1.2 Method 2: Dehydrohalogenation of Cyclopropylacetyl Halides 659
23.14.3.1.3 Method 3: Wolff Rearrangements of Diazo Ketones 659
23.14.3.1.3.1 Variation 1: (Cycloprop 2 enyl)ketene by Wolff Rearrangement 661
23.14.3.1.3.2 Variation 2: Oxiranylketenes by Wolff Rearrangement 662
XXVIII Table of Contents
23.14.3.1.4 Method 4: Photochemical Rearrangement of 5,5 Dimethylcyclopent 2
enone 662
23.14.3.1.4.1 Variation 1: Photolysis of Cyclopentadienones 662
23.14.3.2 Applications of Product Subclass 3 in Organic Synthesis 663
23.14.3.2.1 Method 1: Bicyclooctadienones and Cycloheptadienones from
Cyclopropylketenes by Cope Rearrangement 663
23.14.4 Product Subclass 4: (Fluoroalkyl)ketenes 665
23.14.4.1 Synthesis of Product Subclass 4 666
23.14.4.1.1 Method 1: Dehydration of Fluoroalkanoic Acids 666
23.14.4.1.2 Method 2: Dehalogenation of 2 Haloacyl Halides 666
23.14.4.1.3 Method 3: Wolff Rearrangement of Diazo Ketones 667
23.14.4.1.3.1 Variation 1: Bis(trifluoromethyl)ketene by Wolff Type Rearrangement
upon Oxidation of an Alkyne 667
23.14.4.1.4 Method 4: Hydrolysis of a Perfluoroalkene 668
23.14.4.1.5 Method 5: Acyl(trifluoromethyl)ketenes by Cleavage of a
1,3 Dioxin 4 one 668
23.14.4.2 Applications of Product Subclass 4 in Organic Synthesis 668
23.14.4.2.1 Method 1: Fluoroalkyl Cyclobutanones, Cyclobutenones, and Derivatives
by [2 + 2] Cycloaddition Reactions of (Fluoroalkyl)ketenes — 668
23.14.4.2.2 Method 2: (Trifluoromethyl)malonates by Nucleophilic Additions to a
(Trifluoromethyl)ketene 671
23.15 Product Class 15: Bisketenes
T. T. Tidwell
23.1S Product Class 15: Bisketenes 679
23.15.1 Product Subclass 1:1,2 Bisketenes 681
23.15.1.1 Synthesis of Product Subclass 1 681
23.15.1.1.1 Method 1: 1,2 Bisketenes by Thermal Ring Opening of
Cyclobutene 1,2 diones 682
23.15.1.1.1.1 Variation 1: Stabilized 1.2 Bisketenes by Thermal Ring Opening of
Cyclobutene 1,2 diones 683
23.15.1.1.2 Method 2: 1,2 Bisketenes by Photochemical Ring Opening of
Cyclobutene 1,2 diones 684
23.15.1.1.3 Method 3: Metal Complexed 1,2 Bisketene 687
23.15.1.1.4 Method 4: 1,2 Bisketenes by Wolff Rearrangement of Bis(diazo ketones) 687
23.15.1.2 Applications of Product Subclass 1 in Organic Synthesis 688
23.15.1.2.1 Method 1: Acids, Esters, and Amides by Nucleophilic Additions to
1,2 Bisketenes 688
23.15.1.2.1.1 Variation 1: (Carboxy)ketenes and Succinic Anhydrides by Water Addition
to 1,2 Bisketenes 691
23.15.1.2.2 Method 2: Diamides by Amine Addition to 1,2 Bisketenes 692
23.15.1.2.2.1 Variation 1: Carbamoyl Substituted Esters by Successive Amine and
Alcohol Addition 692
Table of Contents XXIX
23.15.1.2.2.2 Variation 2: A Cyclic Carbamoyl Ester by Addition of an Amino Alcohol
to a 1,2 Bisketene 693
23.15.1.2.3 Method 3: A Fumaroyl Bromide by Bromine Addition to a 1,2 Bisketene • 693
23.15.1.2.4 Method 4: Maleic Anhydride Formation by Aminoxyl Radical Addition
to a 1,2 Bisketene 694
23.15.1.2.5 Method 5: Furanone Formation by Dimerization of 1,2 Bisketenes 694
23.15.1.2.6 Method 6: Naphthofuranones by [4+2] Cycloaddition of 1,2 Bisketenes
with Pendant Alkenes 695
23.15.1.2.7 Method 7: Cyclopropenes and Quinones by [2 + 1] and [4 + 2]
Cycloaddition of 1,2 Bisketenes with Alkynes 695
23.15.1.2.8 Method 8: A P Lactone by [2 + 2] Cycloaddition of a 1,2 Bisketene with
Acetaldehyde 697
23.15.1.2.9 Method 9: Cyclopentenediones by [4+1 ] Cycloaddition of
1,2 Bisketenes with Carbenes and Diazoalkanes 697
23.15.1.2.10 Method 10: Cyclopropenones and Alkynes by Photolysis of 1,2 Bisketenes 697
23.15.2 Product Subclass 2:1,3 and Higher Bisketenes 699
23.15.2.1 Synthesis of Product Subclass 2 699
23.15.2.1.1 Method 1: A Bisketene by Dehydration of a Dicarboxylic Acid 699
23.15.2.1.2 Method 2: A Bisketene by Elimination from a Bis(isopropenyl) Ester 700
23.15.2.1.3 Method 3: Bisketenes by Dehydrochlorination of Dicarboxylic Acid
Chlorides 701
23.15.2.1.3.1 Variation 1: Bisketenes by Dehydrochlorination of Dicarboxylic Acid
Chlorides by a Shuttle Procedure with a Kinetic Base and
a Stoichiometric Base 702
23.15.2.1.3.2 Variation 2: 1,4 Bis(oxovinyl)benzenes by Dehydrochlorination 705
23.15.2.1.4 Method 4: Bisketenes by Ring Opening of Benzo 1,2 quinones 705
23.15.2.1.5 Method 5: Bisketenes by Wolff Rearrangement of Bis(diazo ketones) •••• 706
23.15.2.1.6 Method 6: Bis and Tris(oxovinyl)silanes by Thermolysis of
(Ethoxyethynyl)silanes 707
23.15.2.1.7 Method 7: A 1,5 Bisketene by [4+2] Cycloaddition of Norbornadiene
with a 1,3,4 Oxadiazine Followed by Nitrogen Elimination • • • 710
23.15.2.1.8 Method 8: A Bis(allenylketene) from a Bis(methylenecyclobutenone) • • • 710
23.15.2.2 Applications of Product Subclass 2 in Organic Synthesis 711
23.15.2.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to Bisketenes 711
23.15.2.2.1.1 Variation 1: Polyamides and Polyesters from Bisketenes and Diamines or
Diols 711
23.15.3 Product Subclass 3: Bis(oxomethylene)cyclohexanes and
cyclohexadienes 712
23.15.3.1 Synthesis of Product Subclass 3 713
23.15.3.1.1 Method 1: Bis(oxomethylene)cyclohexanes and cyclohexadienes by
Dehydrochlorination of Dicarboxylic Acid Chlorides 713
23.15.3.1.2 Method 2: Bis(oxomethylene)cydohexadienes by Dehalogenation of
Terephthaloyl Halides 714
23.15.3.1.3 Method 3: 1,2 Bis(oxomethylene)cyclohexane by Ring Opening of a
Cyclobutene 1,2 dione 714
XXX Table of Contents
23.15.3.1.4 Method 4: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Ring Opening
of aCyclobutene 1,2 dione 715
23.15.3.1.4.1 Variation 1: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Thermal
Nitrogen Loss from Phthalazine 1,4 dione 716
23.15.3.1.5 Method 5: 5,6 Bis(oxomethylene)cyclohexa 1,3 diene by Cyclophane
Cleavage 716
23.15.3.1.6 Method 6: Bis(oxomethylene)cycloalkanes by Double Wolff
Rearrangement 716
23.15.3.2 Applications of Product Subclass 3 in Organic Synthesis 717
23.15.3.2.1 Method 1: Esters and Amides by Addition of Nucleophiles to Bisketenes 717
23.15.3.2.2 Method 2: [4+2] Cycloadditions of 1,2 Bisketenes with Alkenes and
Benzoquinones 718
23.15.3.2.3 Method 3: Spiro[cyclopropane 1,T(3'H) isobenzofuran] 3' ones by
Cycloaddition of a 1,2 Bisketene with Alkenes 719
23.15.3.2.4 Method 4: A 1,3,5 Oxathiazine by [4+2] Cycloaddition of a Bisketene
with an Isocyanate 721
23.15.3.2.5 Method 5: Benzyne by Photochemical Decarbonylation of
5,6 Bis(oxomethylene)cydohexa 1,3 diene 721
23.153.2.5.1 Variation 1: A Bicyclic Enyne by Photochemical Decarbonylation of a
Bisketene 721
23.15.3.2.6 Method 6: Polymerization of a 1,4 Bisketene by [2 + 2] Cyclodimerization 722
23.15.4 Product Subclass 4: Other Bisketenes 722
23.i5.4i Synthesis of Product Subclass 4 722
23.15.4.1.1 Method 1: Bis(acylketenes) by Thermolysis of Bis(dioxinones) and
Bis(Meldrum's acid) Derivatives 722
23.15.4.1.2 Method 2: A Tris(acylketene) by Thermolysis of a Triester 726
23.15.4.1.3 Method 3: A Bis(acylketene) by Carbon Dioxide Addition to a
Diynediamine 726
23.15.4.1.4 Method 4: Bis(acylketenes) by Wolff Rearrangement of Bis(diazo)
Tetraketones 727
23.15.4.1.4.1 Variation 1: Cyclic Bis(acylketene) Formation by a Wolff Type
Rearrangement 727
23.15.4.1.5 Method 5: Bis(dienylketenes) by Photolysis of Bis(cyclohexadienones) • • 728
23.15.4.1.6 Method 6: A Bis(oxovinyl)platinum Complex by Addition of a Ketene
to an (Oxovinyl)platinum Complex 729
23.15.4.1.7 Method 7: Bis(ketenechromium) Complexes from
Bis(alkylidenechromium) Complexes 730
23.16 Product Class 16: Sulfur, Selenium, and Tellurium Analogues of Ketenes
C. Spanka and E. Schaumann
23.16 Product Class 16: Sulfur, Selenium, and Tellurium Analogues of Ketenes ¦ 735
23.16.1 Product Subclass 1: Thioketenes 735
23.16.1.1 Synthesis of Product Subclass 1 736
23.16.1.1.1 Method 1: Sulfuration of Ketenes 736
Table of Contents XXXI
23.16.1.1.2 Method 2: Synthesis from Dithiocarboxylates 738
23.16.1.1.3 Method 3: Elimination Reactions of Ketene S,X Acetals 739
23.16.1.1.4 Method 4: Synthesis by Cycloreversion 740
23.16.1.1.4.1 Variation 1: [2 + 2] Cycloreversion of 2,4 Bis(alkylidene) 1,3 dithietanes
(Thioketene Dimers) or4 Alkylidene 1,3 dithietan 2 ones ¦•¦ 740
23.16.1.1.4.2 Variation 2: [3 + 2] Cycloreversion of 2 Alkylidene 1,3 dithiolane
Derivatives 742
23.16.1.1.4.3 Variation 3: 1,2,3 Thiadiazoles as Stable Thioketene Precursors
(Thio Wolff Rearrangement) 746
23.16.1.1.5 Method 5: Treatment of Alkylidenephosphoranes with Carbon Disulfide ¦ 750
23.16.1.1.6 Method 6: Thioketenes via Alkynyl Sulfides 751
23.16.1.1.6.1 Variation 1: Protonation orSilylation of Alk 1 ynethiolates Followed
by [1,3] Hydrogen/Silicon Shift 753
23.16.1.1.6.2 Variation 2: Thia Cope Rearrangement of Alkynyl Allyl Sulfides 754
23.16.1.1.7 Methods 7: Other Methods 758
23.16.2 Product Subclass 2: Cumulated Thioketenes and Their Derivatives 760
23.16.2.1 Synthesis of Product Subclass 2 760
23.16.2.1.1 Methodi: Synthesis of Alkylidenethioketenes 760
23.16.2.1.2 Method 2: Synthesis of (Arylimino)thioketenes 761
23.16.2.1.3 Method 3: Synthesis of Carbon Subsulfide (Propadienedithione) 762
23.16.3 Product Subclass 3: Thioketene S Oxides 764
23.16.3.1 Synthesis of Product Subclass 3 764
23.16.3.1.1 Methodi: Direct Oxidation of Thioketenes 764
23.16.3.1.2 Method 2: [3+2] Cycloreversion of 1,3 Dithiolane 1,1,3 Trioxides 765
23.16.3.1.3 Method 3: Retro Diels Alder Reaction 765
23.16.4 Product Subclass 4: Selenoketenes 766
23.16.4.1 Synthesis of Product Subclass 4 766
23.16.4.1.1 Method 1: Rearrangement of Alkynyl Selenides 767
23.16.4.1.2 Method 2: [3,3] Sigmatropic Rearrangement of Alkynyl Allyl Selenides
(Selena Cope Rearrangement) 769
23.16.4.1.3 Method 3: Nitrogen Extrusion from 1,2,3 Selenadiazoles 772
23.16.5 Product Subclass 5: Telluroketenes 776
23.17 Product Class 17: Ketenimines
H. Perst
23.17 Product Class 17: Ketenimines 781
23.17.1 Product Subclass 1: Monoketenimines 783
23.17.1.1 Synthesis of Product Subclass 1 783
23.17.1.1.1 Synthesis by Formation of the C=C Bond 784
23.17.1.1.1.1 Methodi: Dehydrocyanation of Imidoyl Cyanides 784
23.17.1.1.1.2 Method 2: Dehydration of Carboxamides by Oxophilic Reagents in the
Presence of Tertiary Amines 785
XXXII Table of Contents
23.17.1.1.1.2.1 Variation 1: Using Triphenylphosphine Carbon
Tetrachloride Triethylamine 787
23.17.1.1.1.2.2 Variation 2: Using Triphenylphosphine Bromine Triethylamine 788
23.17.1.1.1.2.3 Variation 3: Using Diphosgene Triethylamine 791
23.17.1.1.1.3 Method 3: p Elimination from Imidocarboxylic Acid Derivatives 793
23.17.1.1.1.3.1 Variation 1: Dehydrohalogenation of Imidoyl Halides 793
23.17.1.1.1.3.2 Variation 2: Dehalogenation of a Haloimidoyl Halides 795
23.17.1.1.1.3.3 Variation 3: p Elimination from Imidocarboxylic Acid Esters 796
23.17.1.1.1.4 Method 4: P Elimination from Other Precursors via Imidocarboxylic
Acid Derivatives Formed In Situ 798
23.17.1.1.1.4.1 Variation 1: From Oximes 798
23.17.1.1.1.4.2 Variation 2: From 2,2 Dihaloaziridines 799
23.17.1.1.1.5 Method 5: Elimination of Hydrogen Sulfide from Thioamides 801
23.17.1.1.1.5.1 Variation 1: From Thioamides via Imidoyl Chlorides 801
23.17.1.1.1.5.2 Variation 2: From Methyl Imidothioesters 802
23.17.1.1.1.6 Method 6: Connective Alkene Formation by Reaction of Phosphonium
Ylides or Related Reagents with Azaheterocumulenes 804
23.17.1.1.1.6.1 Variation 1: Ketenimines from Wittig Reaction of Alkylidenetriphenyl
phosphoranes with Isocyanates 804
23.17.1.1.1.6.2 Variation 2: Reaction of Alkylidenephosphoranes with Isothiocyanates
or Carbodiimides 808
23.17.1.1.1.6.3 Variation 3: Horner Wittig Reaction of Isocyanates with Carbanions
Derived from Diethyl Phosphonates 809
23.17.1.1.1.7 Method 7: Cycloreversion 809
23.17.1.1.1.8 Method 8: Cheletropic Reactions (Sulfur Extrusion from
2,5 Dihydroisothiazol 5 imines) 811
23.17.1.1.1.9 Method 9: Addition of Isocyanides to Carbenes 812
23.17.1.1.1.10 Method 10: Addition of Isocyanides to Suitable Carbon Fragments
in the Coordination Sphere of Transition Metal Complexes • • ¦ 814
23.17.1.1.1.10.1 Variation 1: Addition of Carbenes to Transition Metal lsocyanide
Complexes 814
23.17.1.1.1.10.2 Variation 2: Addition of Isocyanides to Transition Metal Carbene
Complexes 815
23.17.1.1.1.10.3 Variation 3: Rearrangement of a Transition Metal lsocyanide Complex • • • 816
23.17.1.1.1.10.4 Variation 4: Palladium Assisted Reactions of Isocyanides with Alkyl
Chlorides 817
23.17.1.1.1.11 Method 11: Addition of Isocyanides to Alkynes 818
23.17.1.1.1.12 Method 12: Addition of Isocyanides to Cyclopropene Derivatives 820
23.17.1.1.1.13 Method 13: Iminocarbene Ketenimine Rearrangement 821
23.17.1.1.1.13.1 Variation 1: Photochemical Transformation of 2 (Cyanoimino) 1 diazoal
kanes 821
23.17.1.1.1.13.2 Variation 2: Thermal or Photochemical Transformation of
1 Aryl 1,2,3 triazolesand 1 H Benzotriazoles 822
23.17.1.1.2 Synthesis by Formation of the C=N Bond 824
23.17.1.1.2.1 Method 1: Dehydrocyanation of a Cyanoenamines 825
23.17.1.1.2.2 Method 2: Dehydrohalogenation of a Haloenamines 826
23.17.1.1.2.3 Method 3: Eliminations from Ketene N,5 Acetals 828
Table of Contents XXXIII
23.17.1.1.2.4 Method 4: Connective Imine Formation by Aza Wittig Reaction of
Iminophosphoranes or Related Compounds with Ketenes — 831
23.17.1.1.2.4.1 Variation 1: With Preformed Iminophosphoranes and Preformed Ketenes 831
23.17.1.1.2.4.2 Variation 2: With Preformed Iminophosphoranes and In Situ Generated
Ketenes 833
23.17.1.1.2.4.3 Variation 3: With In Situ Generated Iminophosphoranes and Preformed
Ketenes 833
23.17.1.1.2.4.4 Variation 4: Reaction of N Substituted Diethyl Phosphoramidate Anions
with Ketenes 837
23.17.1.1.2.5 Method 5: Connective Imine Formation by the Reaction of Thioketenes
with Sulfur Diimides 838
23.17.1.1.2.6 Method 6: Deprotonation and Ring Opening of Isoxazolium Salts 839
23.17.1.1.2.7 Method 7: Cycloreversion 840
23.17.1.1.2.8 Method 8: Cheletropic Reactions 840
23.17.1.1.2.9 Method 9: Thermolysis of Vinyl Azides 843
23.17.1.1.2.10 Method 10: Photolysis of Vinyl Azides or Aryl Azides 844
23.17.1.1.3 Synthesis by Formation of the C=C and C=N Bonds 845
23.17.1.1.3.1 Method 1: Addition Elimination Reactions with Nitriles 845
23.17.1.1.3.1.1 Variation 1: Via Nitrilium Ions and Subsequent Deprotonation at the
P Carbon Atom 845
23.17.1.1.3.1.2 Variation 2: Via Nitrile Anions and Subsequent Addition of Electrophiles
to the Nitrogen Atom 846
23.17.1.1.3.1.3 Variation 3: Addition of Trialkyl Phosphites to a Halo Nitriles and
Elimination of Haloalkanes 849
23.17.1.1.3.2 Method 2: 1,4 Addition to a.p Unsaturated Nitriles 851
23.17.1.1.3.3 Method 3: [2,3] Sigmatropic Rearrangement of 1 Cyanoalkyl
Methylenesulfur Ylides 852
23.17.1.2 Applications of Product Subclass 1 in Organic Synthesis 854
23.17.1.2.1 Method 1: Addition of Protic Nucleophiles and Related Compounds •¦¦• 854
23.17.1.2.2 Method 2: [2+2] Cycloaddition Reactions of Ketenimines 856
23.17.1.2.2.1 Variation 1: With Alkenes or Alkynes 856
23.17.1.2.2.2 Variation 2: With Carbonyl Compounds 858
23.17.1.2.2.3 Variation 3: With Thiocarbonyl Compounds 859
23.17.1.2.2.4 Variation 4: With Imines 861
23.17.1.2.2.5 Variation 5: With N=X Systems 862
23.17.1.2.2.6 Variation 6: With Heterocumulenes 864
23.17.1.2.3 Method 3: [3+ 2] Cycloaddition Reactions of Ketenimines 865
23.17.1.2.3.1 Variation 1: With 1,3 Dipoles 865
23.17.1.2.3.2 Variation 2: With Three Membered Heterocycles 867
23.17.1.2.3.3 Variation 3: Via Intramolecular Reactions of C (Aziridin 1 yliminojketen
imines 869
23.17.1.2.4 Method 4: [4+2] Cycloaddition Reactions Using Ketenimines as
Dienophiles 870
23.17.1.2.5 Method 5: [4 + 2] Cycloaddition Reactions Using Ketenimines as
1,3 Dienes 871
23.17.1.2.5.1 Variation 1: From a 1,3 Diene Formed by the Ketenimine C=C Bond
and a Suitable C Substituent 874
XXXIV Table of Contents
23.17.1.2.5.2 Variation 2: From a 1,3 Diene Formed by the Ketenimine C=C Bond
and a C Aryl Substituent; Intramolecular [4+2] Cycloaddition
Reactions 877
23.17.1.2.5.3 Variation 3: From a 1,3 Diene Formed by the Ketenimine C=N Bond
and a Suitable N Substituent 879
23.17.1.2.5.4 Variation 4: From a 1,3 Diene Formed by the Ketenimine C=N Bond
and an N Aryl Substituent 882
23.17.1.2.6 Method 6: Rearrangements of Ketenimines 884
23.17.1.2.7 Method 7: Reactions with Loss of the N Substituent 885
23.17.1.2.7.1 Variation 1: Thermal Cleavage 885
23.17.1.2.7.2 Variation 2: Addition Elimination Reactions of /V Silyl or
N Stannylketenimines 886
23.17.1.2.7.3 Variation 3: Alk 2 enenitriles from C,C,A/ Tris(trimethylsilyl)ketenimine
and Aldehydes 888
23.17.2 Product Subclass 2: Bisiminopropa 1,2 dienes 889
23.17.2.1 Synthesis of Product Subclass 2 889
23.17.2.1.1 Method 1: Thermolysis of Isoxazolonoketene N,S Acetals 889
Keyword Index 899
Author Index 1013
Abbreviations 1049 |
| any_adam_object | 1 |
| any_adam_object_boolean | 1 |
| author | Aizpurua, J. M. |
| author2 | Danheiser, R. L. |
| author2_role | edt |
| author2_variant | r l d rl rld |
| author_GND | (DE-588)117013870 |
| author_facet | Aizpurua, J. M. Danheiser, R. L. |
| author_role | aut |
| author_sort | Aizpurua, J. M. |
| author_variant | j m a jm jma |
| building | Verbundindex |
| bvnumber | BV021603053 |
| ctrlnum | (OCoLC)633828299 (DE-599)BVBBV021603053 |
| format | Book |
| fullrecord | <?xml version="1.0" encoding="UTF-8"?><collection xmlns="http://www.loc.gov/MARC21/slim"><record><leader>00000nam a22000008cc4500</leader><controlfield tag="001">BV021603053</controlfield><controlfield tag="003">DE-604</controlfield><controlfield tag="005">20230823</controlfield><controlfield tag="007">t</controlfield><controlfield tag="008">060601s2006 a||| |||| 00||| eng d</controlfield><datafield tag="020" ind1=" " ind2=" "><subfield code="a">3131187417</subfield><subfield code="9">3-13-118741-7</subfield></datafield><datafield tag="020" ind1=" " ind2=" "><subfield code="a">1588902005</subfield><subfield code="9">1-58890-200-5</subfield></datafield><datafield tag="020" ind1=" " ind2=" "><subfield code="a">9783131187413</subfield><subfield code="9">978-31-3-118741-3</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(OCoLC)633828299</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(DE-599)BVBBV021603053</subfield></datafield><datafield tag="040" ind1=" " ind2=" "><subfield code="a">DE-604</subfield><subfield code="b">ger</subfield><subfield code="e">rda</subfield></datafield><datafield tag="041" ind1="0" ind2=" "><subfield code="a">eng</subfield></datafield><datafield tag="049" ind1=" " ind2=" "><subfield code="a">DE-355</subfield><subfield code="a">DE-20</subfield><subfield code="a">DE-19</subfield><subfield code="a">DE-210</subfield><subfield code="a">DE-91G</subfield><subfield code="a">DE-188</subfield><subfield code="a">DE-11</subfield></datafield><datafield tag="100" ind1="1" ind2=" "><subfield code="a">Aizpurua, J. M.</subfield><subfield code="4">aut</subfield></datafield><datafield tag="245" ind1="1" ind2="0"><subfield code="a">Science of synthesis</subfield><subfield code="b">Houben-Weyl methods of molecular transformations</subfield><subfield code="n">23 = Category 3, Compounds with four and three carbon-heteroatom bonds</subfield><subfield code="p">Three carbon-heteroatom bonds: ketenes and derivatives</subfield><subfield code="c">ed. board: D. Bellus ...</subfield></datafield><datafield tag="264" ind1=" " ind2="1"><subfield code="a">Stuttgart [u.a.]</subfield><subfield code="b">Thieme</subfield><subfield code="c">2006</subfield></datafield><datafield tag="300" ind1=" " ind2=" "><subfield code="a">XXXIV, 1054 Seiten</subfield><subfield code="b">Illustrationen</subfield><subfield code="c">26 cm</subfield></datafield><datafield tag="336" ind1=" " ind2=" "><subfield code="b">txt</subfield><subfield code="2">rdacontent</subfield></datafield><datafield tag="337" ind1=" " ind2=" "><subfield code="b">n</subfield><subfield code="2">rdamedia</subfield></datafield><datafield tag="338" ind1=" " ind2=" "><subfield code="b">nc</subfield><subfield code="2">rdacarrier</subfield></datafield><datafield tag="700" ind1="1" ind2=" "><subfield code="a">Bellus, Daniel</subfield><subfield code="e">Sonstige</subfield><subfield code="4">oth</subfield></datafield><datafield tag="700" ind1="1" ind2=" "><subfield code="a">Danheiser, R. L.</subfield><subfield code="4">edt</subfield></datafield><datafield tag="700" ind1="1" ind2=" "><subfield code="a">Houben, Josef</subfield><subfield code="d">1875-1940</subfield><subfield code="e">Sonstige</subfield><subfield code="0">(DE-588)117013870</subfield><subfield code="4">oth</subfield></datafield><datafield tag="773" ind1="0" ind2="8"><subfield code="w">(DE-604)BV013247070</subfield><subfield code="g">23</subfield></datafield><datafield tag="776" ind1="0" ind2="8"><subfield code="i">Erscheint auch als</subfield><subfield code="n">Online-Ausgabe</subfield><subfield code="z">978-31-3-183751-6</subfield></datafield><datafield tag="856" ind1="4" ind2="2"><subfield code="m">HBZ Datenaustausch</subfield><subfield code="q">application/pdf</subfield><subfield code="u">http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=014818364&sequence=000002&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA</subfield><subfield code="3">Inhaltsverzeichnis</subfield></datafield><datafield tag="943" ind1="1" ind2=" "><subfield code="a">oai:aleph.bib-bvb.de:BVB01-014818364</subfield></datafield></record></collection> |
| id | DE-604.BV021603053 |
| illustrated | Illustrated |
| index_date | 2024-07-02T14:48:23Z |
| indexdate | 2024-08-20T00:15:12Z |
| institution | BVB |
| isbn | 3131187417 1588902005 9783131187413 |
| language | English |
| oai_aleph_id | oai:aleph.bib-bvb.de:BVB01-014818364 |
| oclc_num | 633828299 |
| open_access_boolean | |
| owner | DE-355 DE-BY-UBR DE-20 DE-19 DE-BY-UBM DE-210 DE-91G DE-BY-TUM DE-188 DE-11 |
| owner_facet | DE-355 DE-BY-UBR DE-20 DE-19 DE-BY-UBM DE-210 DE-91G DE-BY-TUM DE-188 DE-11 |
| physical | XXXIV, 1054 Seiten Illustrationen 26 cm |
| publishDate | 2006 |
| publishDateSearch | 2006 |
| publishDateSort | 2006 |
| publisher | Thieme |
| record_format | marc |
| spelling | Aizpurua, J. M. aut Science of synthesis Houben-Weyl methods of molecular transformations 23 = Category 3, Compounds with four and three carbon-heteroatom bonds Three carbon-heteroatom bonds: ketenes and derivatives ed. board: D. Bellus ... Stuttgart [u.a.] Thieme 2006 XXXIV, 1054 Seiten Illustrationen 26 cm txt rdacontent n rdamedia nc rdacarrier Bellus, Daniel Sonstige oth Danheiser, R. L. edt Houben, Josef 1875-1940 Sonstige (DE-588)117013870 oth (DE-604)BV013247070 23 Erscheint auch als Online-Ausgabe 978-31-3-183751-6 HBZ Datenaustausch application/pdf http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=014818364&sequence=000002&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA Inhaltsverzeichnis |
| spellingShingle | Aizpurua, J. M. Science of synthesis Houben-Weyl methods of molecular transformations |
| title | Science of synthesis Houben-Weyl methods of molecular transformations |
| title_auth | Science of synthesis Houben-Weyl methods of molecular transformations |
| title_exact_search | Science of synthesis Houben-Weyl methods of molecular transformations |
| title_exact_search_txtP | Science of synthesis Houben-Weyl methods of molecular transformations |
| title_full | Science of synthesis Houben-Weyl methods of molecular transformations 23 = Category 3, Compounds with four and three carbon-heteroatom bonds Three carbon-heteroatom bonds: ketenes and derivatives ed. board: D. Bellus ... |
| title_fullStr | Science of synthesis Houben-Weyl methods of molecular transformations 23 = Category 3, Compounds with four and three carbon-heteroatom bonds Three carbon-heteroatom bonds: ketenes and derivatives ed. board: D. Bellus ... |
| title_full_unstemmed | Science of synthesis Houben-Weyl methods of molecular transformations 23 = Category 3, Compounds with four and three carbon-heteroatom bonds Three carbon-heteroatom bonds: ketenes and derivatives ed. board: D. Bellus ... |
| title_short | Science of synthesis |
| title_sort | science of synthesis houben weyl methods of molecular transformations three carbon heteroatom bonds ketenes and derivatives |
| title_sub | Houben-Weyl methods of molecular transformations |
| url | http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=014818364&sequence=000002&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA |
| volume_link | (DE-604)BV013247070 |
| work_keys_str_mv | AT aizpuruajm scienceofsynthesishoubenweylmethodsofmoleculartransformations23category3compoundswithfourandthreecarbonheteroatombonds AT bellusdaniel scienceofsynthesishoubenweylmethodsofmoleculartransformations23category3compoundswithfourandthreecarbonheteroatombonds AT danheiserrl scienceofsynthesishoubenweylmethodsofmoleculartransformations23category3compoundswithfourandthreecarbonheteroatombonds AT houbenjosef scienceofsynthesishoubenweylmethodsofmoleculartransformations23category3compoundswithfourandthreecarbonheteroatombonds |