Methanol → L-Cysteine, methyl ester, hydrochloride

Participants

Reaction Conditions

Reaction Steps

To a suspension of (R)-cysteine (40.0 g, 0.330 mole) in 400 ml of methanol maintained under nitrogen at -78° C. was added thionyl chloride (28 ml, 0.384 mole). The cysteine slowly dissolved to form a clear solution. The solution was stirred overnight at room temperature and then evaporated under vacuum to yield (R)-cysteine methyl ester hydrochloride as a colorless, sticky syrup (57.0 g, 100% yield). The product solidified upon standing.

Provenance & Evidence