Microwave-assisted efficient synthesis of aryl ketone β-C-glycosides from unprotected aldoses

Condensation between unprotected aldoses and dibenzoylmethane catalyzed by NaHCO3 in the cosolvents EtOH and H2O (4:1) under microwave irradiation gave aryl ketone β-C-glycosides 6b–i in higher yields (from 50% with C-riboside 6g up to 99% with C-glucoside 6b) and better anomeric selectivities (β-configuration >95%) in a shorter reaction time (90 min), compared with previous conventional methodologies. This method provides an attractive alternative to the existing means for the preparation of high value ketone β-C-glycosides.