Direct, mild, and selective synthesis of unprotected dialdo-glycosides

A direct and highly convenient organocatalytic method for the preparation of 1,5-dialdo-pyranosides and 1,4-dialdo-furanosides is presented. The method relies on the chemoselective properties of TEMPO in combination with trichloroisocyanuric acid under very mild, basic conditions. Unprotected glycosides are prepared in a single step in high yields and are efficiently purified with the use of solid-phase imine capture. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).