Ethylmorpholine → (S)-1-(tert-Butyl)pyrrolidine-2-carboxamide

Participants

Reaction Steps

A solution of 650 mg of N2 -[3(S)-amino-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide and 538 mg of N-(benzyloxycarbonyl)-S-methyl-L-cysteine in 20 ml of dry tetrahydrofuran was cooled in an ice/salt mixture. 270 mg of hydroxybenzotriazole, 230 mg of N-ethylmorpholine and 412 mg of dicyclohexylcarbodiimide were added and the mixture was stirred for 16 hours. The mixture was diluted with ethyl acetate and filtered. The filtrate was washed with aqueous sodium bicarbonate solution and sodium chloride solution. The solvent was removed by evaporation and the residue was chromatographed on silica gel using System G for the elution to give 800 mg of N2 -[3(S) [N-(benzyloxycarbonyl)-S-methyl-L-cysteinyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide; MS: m/e 585 [M+H]+.

Provenance & Evidence