Dicyclohexylcarbodiimide → N-(3-acetylthio-2-trifluoromethylpropanoyl)-L-proline tertbutyl ester

Participants

Reaction Steps

L-proline tert-butyl ester (5.1 g.) is dissolved in dichloromethane (40 ml.) and the solution is stirred and chilled in an ice bath. Dicyclohexylcarbodiimide (6.2 g.) dissolved in dichloromethane (15 ml.) is added followed immediately by a solution of 3-acetylthio-2-trifluoromethylpropanoic acid (6.5 g.) in dichloromethane (5 ml.). After fifteen minutes stirring in the ice bath and sixteen hours at room temperature, the precipitate formed is filtered off and the filtrate is concentrated to dryness in vacuo. The residue is dissolved in ethyl acetate and washed neutral. The organic phase is dried over magnesium sulfate and concentrated to dryness in vacuo to give N-(3-acetylthio-2-trifluoromethylpropanoyl)-L-proline tert-butyl ester.

Provenance & Evidence