Asymmetric Addition of Hydrogen Cyanide to Substituted Benzaldehydes Catalyzed by a Synthetic Cyclic Peptide, Cyclo (( S )-phenylalanyl-( S )-histidyl)

Abstract

Using cyclo((S)-phenylalanyl-(S)-histidyl) as catalyst, optically active cyanohydrins from substituted benzaldehydes with p-methyl, m-methyl, o-methyl, m-methoxyl, or m-phenoxyl group were obtained with optical yield of 82–33%. For the asymmetric cyanohydrin synthesis, nonpolar solvent such as benzene or carbon tetrachloride was advantageous, while no asymmetric synthesis took place in methanol or dimethyl sulfoxide.