Synthesis of 2,3-unsaturated glycosides via metal-free Ferrier reaction

Hexafluoroisopropanol (HFIP) is explored as an effective medium for the synthesis of 2,3-unsaturated glycosides through allylic rearrangement of 3,4,6-tri-O-acetyl glucal. This metal-free, exclusively solvent-promoted Ferrier glycosylation, affords products in good to excellent yields and with good a-selectivity. (c) 2008 Elsevier Ltd. All rights reserved.