Zn(OTf)_2-Catalyzed Glycosylation of Glycals: Synthesis of 2,3-Unsaturated Glycosides via a Ferrier Reaction

摘要

A mild, catalytic, and efficient protocol has been developed for the synthesis of 2,3-unsaturated glycosides or 'pseudo-glycals' using Zn(OTf)_2. Stereoselective glycosylation of glycal donor with various acceptors comprising of alcohols, phenols, thiols, and sugar aglycones proceeds smoothly to afford the corresponding 2,3-unsaturaed glycosides in good to excellent yields.