Preparation of D-Phenylalanine by Asymmetric Transformation

The method of preparing D-phenylalanine by asymmetric transformation is reported. D-phenylalanine was prepared from DL-phenylalanine by two-step reaction. D-phenylalanine (2S, 3S)-tartrate was prepared by heating DL-phenylalanine, salicylaldehyde, and (2S, 3S)-tartaric acid in propionic acid; the obtained D-phenylalanine (2S, 3S)-tartrate was treated with triethylamine in ethanol giving D-phenylalanine with 98% optical purity in 69% yield.