ABSTRACT
Glycosyl radicals can be generated both thermally and photochemically. While the thermal generations using radical initiators are more popular than the photochemical methods to date, the photochemical path will become increasingly important from the viewpoint of selectivity and “green” chemistry. For example, the photochemical method allows radical generation at low temperature, and such mild conditions would be advantageous for chemo-and stereoselective reactions. In addition, radical generation by direct photolysis enables atom-economical reactions without using radical initiators or promoters. Furthermore, the absence of radical promoters can prevent undesirable competing side reactions of chaincarrying radicals, such as reduction of the glycosyl radical by tin hydride. Because of the importance of glycosyl radicals in organic synthesis, several reviews on this subject have been published recently.
