Aniline → (S)-1-benzyloxycarbonyl-N-phenyl-2-pyrrolidinecarboxamide

Participants

Reaction Steps

In 50 ml of THF was dissolved 4.99 g of N-benzyloxycarbonyl-L-proline (29) and after adding thereto 2.23 g of triethylamine and 2.39 g of ethyl chloroformate, the reaction was maintained for 20 minutes after ice-cooling. To the reaction mixture was added 2.79 g of aniline and the reaction was performed for one hour ice-cooling. The solvent was distilled off, the residue thus formed was dissolved in ethyl acetate, and the solution was washed, in succession, with an aqueous solution of 1N hydrochloric acid, a saturated aqueous sodium hydrogencarbonate solution, and then a saturated aqueous sodium chloride solution. The organic layer thus formed was dried by anhydrous sodium sulfate and then concentrated to dryness. The residue was recrystallized from chloroform-ethyl acetate-hexane to provide 5.20 g of (S)-1-benzyloxycarbonyl-N-phenyl-2-pyrrolidinecarboxamide (93) having a melting point of 143°-144° C.

Provenance & Evidence