Patent ID: 6653498
Filing Date: 2003-11-25
Classification: C12P

Abstract:
A process for preparing optically active cyanohydrin of the formula (II), which comprises reacting an aldehyde of the formula (I) with HCN with intensive mixing at 0 to 60Â° C. in a water-immiscible organic solvent in the presence of an aqueous (R)-hydroxynitrile lyase extract prepared by extracting a (R)-hydroxynitrile-lyase-containing natural product of pH 3.3 to 5.5 with water in the absence of a buffer, separating the organic phase from the aqueous phase, where X, Y and Z in formula (II) have the same meaning as in formula (I), independently of each other are identical or different and are H, F, Cl, Br, I, OH, O(C1-C4-alkyl), OCOCH3, NHCOCH3, NO2 or C1-C4-alkyl.