Radicals and Carbohydrates

Abstract

This article reviews the progress in the area of radicals in carbohydrate chemistry with special attention to new developments published during the past decade. No attempt has been made to present a comprehensive review of the literature but, rather, some specific examples are given to highlight the most synthetically valuable processes. The major focus is on inter‐ and intramolecular carbon–carbon bond‐forming radical reactions, with emphasis on the preparation of C‐glycosides, C‐ketosides, C‐disaccharides, and branched‐chain sugars, as well as on the synthesis of polyfunctionalized carbocycles by radical cyclization of acyclic carbohydrate derivatives. We also describe methods for the formation of carbon–hydrogen bonds, and synthesis in which a heteroatom‐centered radical plays a clear role in the carbon–heteroatom (C–N, C–P, C–O, C–S/Se, and C–Br) bond formation. Finally, a few selected examples of alkoxyl radical β‐fragmentation reactions, carried out under oxidative or reductive conditions, are included to illustrate their potential in the preparation of chiral synthons.