Enantiomerically pure α-fluoroalkyl-α-amino acids: Synthesis of (R)-α-difluoromethyl-alanine and (S)-α-difluoromethyl-serine

Article abstract of DOI:10.1016/0957-4166(96)00287-X

Hydrocyanation of enantiomerically pure N-Cbz α-fluoroalkyl β-sulfinylenamines 1 occurs smoothly by treatment with KCN or by addition of trimethylsilylcyanide or diethyl phosphorocyanidate to preformed sodium derivatives of 1. The diastereoisomeric difluoro α-aminonitriles 2b have been transformed in the unnatural amino acids (R)-α-difluoromethyl-alanine and (S)-α-difluoromethyl-serine.