Stereoselective, Lewis acid-catalyzed glycosylation of alcohols by glucose 1,2-cyclic sulfites
摘要:
alpha-D-Glucopyranose-1,2-cyclic sulfites (1a-c) have been prepared by reaction of a suitably protected glucose residue and thionyl diimidazole. Reaction of these compounds with alcohols in the presence of Yb(OTf)(3) or Ho(OTf)(3) stereoselectively affords beta-O-glycosides