Catalyst for asymmetric induction

Abstract

Optically active cyanohydrins are prepared by addition of hydrogen cyanide to aldehydes in the presence of catalysts which comprise the dipeptide derivative represented by the formula ##STR1## wherein R.sup.1 represents an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a methyl group, a benzyl group or a phenyl group, R.sup.2 represents a benzyl group, an indol-3-ylmethyl group, an isopropyl group, an isobutyl group or a phenyl group, R.sup.3 represents a lower alkoxy group, a hydroxy group or a mono- or di-lower alkylamino group, R.sup.4 represents a hydrogen atom, or R.sup.2 and R.sup.4 are bonded together at their terminals to form a CH.sub.2 CH.sub.2 CH.sub.2 group, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are the same or different, and each represents a hydrogen atom, a halogen atom, a lower alkyl group or a lower alkoxy group or R.sup.5 and R.sup.6, R.sup.6 and R.sup.7, or R.sup.7 and R.sup.8 are bonded together at their terminals to form CH.dbd.CH--CH.dbd.CH or OCH.sub.2 O, and * denotes an absolute configuration of S or R, and a titanium (IV) alkoxide.

Dependencies are inferred from the claim text.