SYNTHESIS OF BENZILS VIA SILICA-GEL SUPPORTED AEROBIC OXIDATION OF ACYLOINS

Supported and catalyzed by silica gel, acyloins were oxidized efficiently by air and excellent yields of α-diketones were prepared. The reaction process is solvent-free and environmentally benign and the silica is recovered and reused directly. Both the influences of the reaction temperature and the amounts of silica gel were investigated. Fourteen examples, including benzils, heterocyclic benzils, polycyclic benzyl and aliphatic α-diketones, were thus obtained with 89 - 96% isolated yields.