Hafnium(IV) triflate as a highly efficient catalyst for Ferrier rearrangement of O- and S-nucleophiles with glycals

Abstract A highly efficient method to afford 2,3-unsaturated glycosides was described. In the presence of Hafnium(IV) triflate, a variety of 2,3-unsaturated- O - and S -glycosides have been obtained by stereoselective glycosylation of 3,4,6-tri- O -acetyl- d -glucal and hexa- O -acetyl- d -lactal with various acceptors in good isolated yields.