Highly asymmetric heterogeneous catalytic hydrogenation of isophorone on proline modified base-supported palladium catalysts

A highly effective asymmetric heterogeneous catalytic hydrogenation of isophorone (3,5,5-trimethyl-2-cyclohexenone) by proline-modified base-supported Pd catalysts is described. Effective combination of enhanced proline adsorption and secondary kinetic resolution resulted in very high enantioselectivities (ee up to 99%). Using (S)- and (R)-proline enantiomers as chiral auxiliaries, both enantiomers of the product were obtained with excellent optical yields. (c) 2006 Elsevier Inc. All rights reserved.