4-Methylmorpholine → N-tert.-butoxycarbonyl-beta-alanyl-L-proline amide

Participants

Reaction Steps

A mixture of 6.28 g (0.0332 m) of N-tert.-butoxycarbonyl-β-alanine, 5.0 g (0.0332 m) of L-proline amide hydrochloride, 8.96 g (0.0664 m) of 1-hydroxybenzotriazole, 12 ml of N-methylmorpholine, 75 ml of tetrahydrofuran, 40 ml of dimethylformamide and 6.84 g (0.0332 m) of dicyclohexylcarbodiimide was stirred at 25° for 17 hours. The solvents were evaporated in vacuo and the residue dissolved in ethyl acetate and water. The separated organic layer was washed with small volumes of dilute hydrochloric acid, brine, 5% bicarbonate and brine. The dried extract was concentrated to give 3.2 g of syrupy N-tert.-butoxycarbonyl-β-alanyl-L-proline amide. The methane chemical ionization mass spectrum was in agreement with the dipeptide structure.

Provenance & Evidence