(R)-Oxynitrilase Catalyzed Synthesis of (R)-Ketone Cyanohydrins

Article abstract of DOI:10.1016/0957-4166(95)00391-6

(R)-Oxynitrilase from almonds (Prunus amygdalus) catalyzed the enantioselective addition of HCN to ethyl alkyl ketones 1 in diisopropyl ether yielding (R)-ethyl alkyl ketone cyanohydrins (R)-2, which are hydrolyzed under acid catalysis to give the α-hydroxy acids (R)-3.This (R)-oxynitrilase also catalyzes the enantioselective addition in aqueous citrate buffer (50 mM, pH 4.0), as demonstrated for the preparation of (R)-methyl alkyl ketone cyanohydrins (R)-5 which are obtained in high enantiomeric excesses comparable to those in diisopropyl ether as solvent.