A practical and efficient α-selective aromatic glycosylation with simple per-O-acetyl glycopyranosyl trichloroacetimidates is reported. The method is particularly effective for L- fucosyl and 2-azido-2-deoxy-d-galatosaminyl imidates, with which exclusive α-selectivity was achieved. The synthetic utility of this method was demonstrated in the stereoselective synthesis of 4-methylumbelliferyl α-T-antigen.
