4-Methylmorpholine → Ethyl N-(1-((benzyloxy)carbonyl)-L-prolyl)-L-leucinate

Participants

Reaction Steps

N-Benzyloxycarbonyl-L-proline (1.25 g), L-leucine ethyl ester hydrochloride (1.00 g) and N-methylmorpholine (1.10 ml) are dissolved in chloroform (10 ml) and thereto is added 4-oxo-3,4-dihydro-3-methanesulfonyloxy-1,2,3-benzotriazine (1.20 g). After allowing to stand overnight, to the mixture are added water and ethyl acetate. The ethyl acetate layer is washed and dried, and then the solvent is distilled off to give N-(N-benzyloxycarbonyl-L-prolyl)-L-leucine ethyl ester (1.3 g), melting point: 65°-67° C.

Provenance & Evidence