Palladium(0)-catalysed synthesis of 2,3- and 3,4-unsaturated aryl ß-O-glycosides.

Arylation of 6-O-tert-butyldiphenylsilyl-3,4-di-O-isobutyloxycarbonyl-d-glucal (3) with various phenols in the presence of a catalytic amount of palladium(0) gave the corresponding 2,3- and 3,4-unsaturated ß-O-glycosides. The reaction is stereospecific, in all cases, only the ß-anomer is formed.