Methanol → 4-Hydroxy-L-proline methyl ester hydrochloride

Participants

Reaction Conditions

Reaction Steps

A solution prepared by dissolving 13.9 g of trans-4-hydroxy-L-proline in 150 ml of methanol was cooled to −20° C. and then 25 ml of thionyl chloride was dropwise added to the solution. After the completion of the dropwise addition, the resulting mixture was stirred at 40° C. for 30 minutes. The reaction solution was concentrated, followed by addition of ether to the resulting residue, filtration of the crystals thus precipitated, washing the crystals with ether and drying them to give 18.86 g (yield 98.0%) of the title compound.

Provenance & Evidence