Oxidative Heck Reaction of Glycals and Aryl Hydrazines: A Palladium-Catalyzed C-Glycosylation

An efficient Heck-type C-glycosylation of glycals via the C-N bond cleavage of aryl hydrazines has been developed. The flexibility of the reaction was tested by the substrate scope, consisting of glycals from different carbohydrate origins as well as aryl hydrazines with various substituents. Pure alpha-C-glycosides were obtained when (3R)-glycals were employed, whereas alpha,beta mixtures were observed with (3S)-glycals.