Benzyl chloroformate → (R)-2-(((Benzyloxy)carbonyl)amino)-3-(phenylthio)propanoic acid

Participants

Reaction Conditions

Reaction Steps

To 62.31 g of an aqueous solution containing 4.55 g of S-phenyl-L-cysteine and maintained at pH 11 with a 30% aqueous solution of sodium hydroxide under constant stirring at about 25° C., 3.94 g of benzyloxycarbonyl chloride (1.0 mole per mole of S-phenyl-L-cysteine) was added dropwise over 1 hour. The mixture was allowed to react for a further 12 hours. The resulting reaction mixture weighed 67.19 g, had a pH value of 10.9, and contained 7.12 g of N-benzyloxycarbonyl-S-phenyl-L-cysteine (concentration 10.6 wt. %; yield 93%). The concentration of sodium chloride in the reaction mixture was 2.7 weight % (based on water). This reaction mixture showed no salting out of N-benzyloxycarbonyl-S-phenyl-L-cysteine sodium salt.

Provenance & Evidence