Photo-induced glycosylation using edible polyphenol sinapinic acid

Photo-induced glycosylation reactions of trichloroacetoimidate donors with alcohol acceptors were investigated under long-wavelength UV light (365 nm) irradiation using the edible polyphenol, sinapinic acid. This study shows, for the first time, that these glycosylations proceeded smoothly under mild reaction conditions to give the corresponding glycosides in high yields. Moreover, the method proved applicable to a broad range of trichloroacetimidate donors and alcohol acceptors, exhibiting excellent chemoselectivity compared with other common donors such as glycosyl phosphites, glycosyl phosphates, fluorides, glycals, thioglycosides, and (N-phenyl)trifluoroacetimidates.