Solution and Solid Phase Synthesis of Unusual a-Amino Acids From

Table of Contents
Abstract .............................................................................................................................. iv
Acknowledgements ............................................................................................................. v
Dedication .......................................................................................................................... vi
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Table of Contents .............................. .... ............................................................................ vii
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List of Tables .................................................................................................................. xiri
List of Figures .................................................................................................................. xiv
List of Abbreviations and Acronyms ........................................................................... xvi
Chapter One
Introduction: The Synthesis of a-Amino Acids
1.1 General Introduction .............................................................................................. 1
1.2 Chernical Synthesis of Racemic a-Amino Acids ............................................... 3
1.2. 1 Addition of the Amino or Carboq Function to the Side Chain ........................... 3
1.2.2 A l@latiott of Glycine Derivatives ................................................................... 4
1.2.3 Other Synthetic Routes to Racemic a-Amino Acids ............................................. 5
1.3 Synthesis of Optidy Active a-Ami00 Acids .......................................................... 5
1.3.1 Enantioselective htruduction of the Mydrogen ............................................. 6
1.3.1.1 Asylluttettic Hydrogenation of &Didehydro Amino Acids ...................... 6
1.3.1.2 Reductive Amination of a-Ketoacids .......................................................... 8
1.3.1.3 Asymmetric Protonation of Enolates ........................................................... 9
1.3.2 Enantiose lective htroduction of the a-Amino Function .................................. 9
1.3.2.1 Nucleophilic Amination ............................................................................. 10
1.3.2.2 Electrophilic Amination of Enolutes ...................................................... 1 2
1.3.3 Stereoselective Introduction of the Side Chain ................................................. 1 3
1.3.3.1 Glycine a-Asion Equivulents .................................................................... 1 3
1.3.3.2 Glycine a-Cation Equivalents ................................................................... 1 8
1.3.4 Synthesis fiom a-Arnim Acids ........................................................................... 1 9
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