A new method for α-selective glycosylation using a donor, glycosyl methyldiphenylphosphonium iodide, without any assistance of acid promoters

A mild and highly alpha-selective glycosylation of several glycosyl acceptors was performed with an in situ formed glycosyl donor, benzyl-protected glycosyl methyldiphenylphosphonium iodide, to afford the corresponding alpha-disaccharides in high yields in CH2Cl2 at room temperature without any assistance of acid promoters.