Butylamine → (S)-1-benzyloxycarbonyl-N-butyl-2-pyrrolidinecarboxamide

Participants

Reaction Steps

In 50 ml of THF was dissolved 4.99 g of N-benzyloxycarbonyl-L-proline and then 2.23 g of triethylamine was added to the solution. Then, after slowly adding thereto 2.39 g of ethyl chloroformate under ice-cooling, the reaction was maintained for one hour at 0° C. to 5° C. Then, 2.19 g of n-butylamine was slowly added to the reaction mixture under ice-cooling, the reaction was further performed for one hour at 0° C. to 5° C. The solvent was removed from the reaction mixture, the residue thus formed was dissolved in ethyl acetate, and the solution was washed successively with an aqueous solution of 1N hydrochloric acid, a saturated aqueous sodium hydrogencarbonate solution, and a saturated aqueous sodium chloride solution. The organic layer this formed was collected, dried by Glauber's salt, and then concentrated to dryness. The product was recrystallized from water to provide 4.31 g of (S)-1-benzyloxycarbonyl-N-butyl-2-pyrrolidinecarboxamide (30). M. p. 88°-90° C.

Provenance & Evidence