Sodium Cyanoborohydride - A Highly Selective Reducing Agent for Organic Functional Groups

The utility of sodium cyanoborohydride as a selective reducing agent for organic synthesis is reviewed. Firstly a summary of the preparation and properties of sodium cyanoborohydride is given. Then some examples of sodium cyanoborohydride reductions of various systems are given including some applications of sodium cyanoborodeuteride. 1. Preparation 2. Purification 3. Physical Properties 4. Chemical Properties 4.1. Hydrolysis 4.2. Exchange 5. Selective Reducing Properties 5.1. Reduction of Aldehydes and Ketones 5.2. Reduction of Oximes 5.3. Reduction of Enamines 5.4. Reductive Amination of Aldehydes and Ketones 5.5. Reductive Alkylation of Amines and Hydrazines 5.6. Reductive Displacement of Halides and Tosylates 5.7. Deoxygenation of Aldehydes and Ketones