CF3SO3H–SiO2 as catalyst for Ferrier rearrangement: an efficient procedure for the synthesis of pseudoglycosides

An efficient method for the conversion of 2,4,6-tri-O-acetyl-d-glucal to 2,3-unsaturated glycosides by using triflic acid on SiO2 as catalyst has been established. A series of 2,3-unsaturated glucosides were synthesized in good yield and high anomeric selectivity under transition metal-free conditions.