Page 23 - Advanced Organic Chemistry Part B - Reactions & Synthesis

3.2. Introduction of Functional Groups by Nucleophilic Substitution xxv
at Saturated Carbon ...................................................................................... 223
Contents
3.2.1. General Solvent Effects..................................................................... 224
3.2.2. Nitriles ............................................................................................... 225
3.2.3. Oxygen Nucleophiles ........................................................................ 226
3.2.4. Nitrogen Nucleophiles....................................................................... 229
3.2.5. Sulfur Nucleophiles........................................................................... 233
3.2.6. Phosphorus Nucleophiles .................................................................. 233
3.2.7. Summary of Nucleophilic Substitution at Saturated Carbon ........... 234
3.3. Cleavage of Carbon-Oxygen Bonds in Ethers and Esters........................... 238
3.4. Interconversion of Carboxylic Acid Derivatives ......................................... 242
3.4.1. Acylation of Alcohols ....................................................................... 243
3.4.2. Fischer Esterification......................................................................... 252
3.4.3. Preparation of Amides....................................................................... 252
3.5. Installation and Removal of Protective Groups........................................... 258
3.5.1. Hydroxy-Protecting Groups .............................................................. 258
3.5.2. Amino-Protecting Groups ................................................................. 267
3.5.3. Carbonyl-Protecting Groups.............................................................. 272
3.5.4. Carboxylic Acid–Protecting Groups................................................. 275
Problems ............................................................................................................... 277

Chapter 4. Electrophilic Additions to Carbon-Carbon Multiple Bonds. . . 289

Introduction........................................................................................................... 289
4.1. Electrophilic Addition to Alkenes................................................................ 290
4.1.1. Addition of Hydrogen Halides.......................................................... 290
4.1.2. Hydration and Other Acid-Catalyzed Additions of Oxygen
Nucleophiles ...................................................................................... 293
4.1.3. Oxymercuration-Reduction ............................................................... 294
4.1.4. Addition of Halogens to Alkenes ..................................................... 298
4.1.5. Addition of Other Electrophilic Reagents ........................................ 305
4.1.6. Addition Reactions with Electrophilic Sulfur and Selenium
Reagents............................................................................................. 307
4.2. Electrophilic Cyclization .............................................................................. 310
4.2.1. Halocyclization.................................................................................. 311
4.2.2. Sulfenylcyclization and Selenenylcyclization................................... 320
4.2.3. Cyclization by Mercuric Ion ............................................................. 324
4.3. Electrophilic Substitution to Carbonyl Groups........................................ 328
4.3.1. Halogenation to Carbonyl Groups ................................................ 328
4.3.2. Sulfenylation and Selenenylation to Carbonyl Groups ................ 331
4.4. Additions to Allenes and Alkynes ............................................................... 333
4.5. Addition at Double Bonds via Organoborane Intermediates ...................... 337
4.5.1. Hydroboration.................................................................................... 337
4.5.2. Reactions of Organoboranes ............................................................. 344
4.5.3. Enantioselective Hydroboration........................................................ 347
4.5.4. Hydroboration of Alkynes................................................................. 352
4.6. Hydroalumination, Carboalumination, Hydrozirconation,
and Related Reactions .................................................................................. 353