Asymmetric sonochemical reactions. Enantioselective hydrogenation of α-ketoesters over platinum catalysts

The sonochemical enantioselective hydrogenation of different α-ketoesters to the corresponding hydroxy derivatives over cinchona modified Pt catalysts is described. Ultrasonic irradiation was found to be beneficial in improving the optical yields. Besides studying the reaction rates and enantioselectivities, the effect of ultrasonics on the catalyst–modifier system and the scale-up of the process will also be considered.