Asymmetric hydrogenation of ketones catalyzed by zeolite-supported gelatin-Fe complex

Zeolite-supported gelatin-iron complex (zeo-gelatin-Fe) was prepared from zeolite, gelatin and ferric chloride, and was found to be useful as a chiral catalyst for the asymmetric hydrogenation of some ketones to corresponding chiral alcohols, such as 2-butanone to (S)-2-butanol, acetophenone to (R)-1-phenylethanol, diacetone alcohol to (S)-2-methyl-2,4-pentane-diol, 3-methyl-2-butanone to (R)-3-methyl-2-butanol and 4-methyl-2-pentanone to (R)-4-methyl-2-pentanol in 52-100% optical yields, respectively, at 20degreesC and under atmospheric hydrogen pressure. In the case of asymmetric hydrogenation of 3-methyl-2-butanone to (R)-3-methyl-2-butanol, when a proper content of iron in the zeo-gelatin-Fe complex and suitable reaction conditions were selected, the product and optical yields could be amounted to 80 and 100%, respectively, and the zeo-gelatin-Fe complex catalyst could be reused several times without remarkable change in the optical catalytic activity. Copyright (C) 2001 John Wiley Sons, Ltd.