Reduction of structurally different carbonyl compounds such as aldehydes, ketones, alpha,beta-unsaturated enals and enones, alpha-diketones and acyloins were accomplished efficiently by sodium borohydride in the presence of wet SiO2 (30% m/m) under solvent free condition. The reactions were performed at room temperature or 75-80 ºC with high to excellent yields of the corresponding products. The chemoselective reduction of aldehydes over ketones was achieved successfully with this reducing system.
reduction; NaBH4; wet SiO2; solvent free