PROCESS FOR THE PREPARATION OF OPTICALLY-ACTIVE CYANOMETHYL ESTERS

摘要

PROCESS FOR THE PREPARATION OF OPTICALLY-ACTIVE CYANOMETHYL ESTERS Stereoisomerically-enriched cyanomethyl esters are prepared by treating a non-symmetrical ketene or an alpha-chiral carboxylic acid halide or reactive derivative thereof with an optically-active alphahydroxynitrile. Certain optically-active optionally substituted S-alpha-cyano-3-phenoxybenzyl alcohol intermediates are prepared by treating the corresponding aldehyde or ketone with a source of hydrogen cyanide in the presence of a substantially water-immiscible, aprotic solvent and a cyclo(D-phenylalanyl-D-histidine) as a catalyst.