Diisopropylethylamine → 4-nitro-N-[[1-(phenylmethyl)cyclopentyl]carbonyl]-L-phenylalanine methyl ester

Participants

Reaction Steps

A solution of 1-benzylcyclopentane carboxylic acid (0.135 g, 0.66 mmol), 4-nitro-L-phenylalanine methyl ester (0.187 g, 0.72 mmol), and HBTU (0.272 g, 0.72 mmol) in 2 mL of DMF was treated with diisopropylethylamine (0.35 mL, 2 mmol). The mixture was stirred over night, concentrated, diluted with ethyl acetate, washed with water, 1 N HCl, water, saturated NaHCO3 and dried (MgSO4). The residue obtained after evaporation was purified by chromatography over 30 g of silica gel, eluting with 40% ethyl acetate:hexane to give 4-nitro-N-[[1-(phenylmethyl)cyclopentyl]carbonyl]-L-phenylalanine methyl ester (194 mg, 71%), as a white foam.

Provenance & Evidence