Acyclic Stereocontrol via [2,3]-Wittig Sigmatropic Rearrangement

Abstract
[2,3]-Sigmatropic rearrangement, which involves an oxycarbanion as the migrating terminus, which is now known as the [2,3]-Wittig rearrangement, is reviewed, highlighting acyclic stereocontrol and natural product synthesis. 1. Introduction 2. Scope and Limitations 2.1. Substrate Variations 2.2. Regioselection in Carbanion Generation 3. Acyclic Stereocontrol 3.1. Basic Transition State Conformation 3.2. Diastereoselection 3.3. Olefinic Stereoselection 3.4. Asymmetric Synthesis 3.4.1. Chirality Transfer 3.4.2. Asymmetric Induction 3.4.3. Chiral Base 4. Sigmatropic Sequences 4.1. Remote Stereocontrol