The First Asymmetric Syntheses of L-Homocysteine and L-Homocystine

Abstract Asymmetric syntheses of l -homocysteine 1 and l -homocystine 2 are described. Alkylation of the carbanion derived from Schollkopf reagent 3 and ensuing hydrolyses gave S -triphenylmethyl- l -homocysteine 6 . Removal of the triphenylmethyl group gave l -homocysteine 1 and subsequent oxidation provided l -homocystine 2 .