Potassium Carbonate → 1-[2-benzoylthio-3-methoxybutanoyl]L-proline

Participants

Reaction Steps

To a solution of L-proline (5.75 g.) in N sodium hydroxide (50 ml.) chilled in an ice bath, 2 N sodium hydroxide (25 ml.) and 2-bromo-3-methoxybutyric acid chloride [obtained from 2-bromo-3-methoxybutyric acid [J. Am. Chem. Soc., 71, 1096, (1949)] and thionyl chloride] (10.7 g.) are added, with vigorous stirring. After three hours, thiobenzoic acid (7.5 g.) and potassium carbonate (4.8 g.) are added and the mixture is stirred at room temperature overnight. The reaction mixture is acidified and extracted with ethyl acetate. The organic layer is concentrated to dryness and the residue is chromatographed on a column of silica gel with benzene-acetic acid to yield 1-[2-benzoylthio-3-methoxybutanoyl]-L-proline.

Provenance & Evidence