反应详情

A solution of dicyclohexylcarbodiimide (DCC, 0.95 g, 4.61 mmol, 1.2 equiv) in 10 mL of dichloromethane (DCM) was added dropwise to a stirred mixture of 4-bromomethyl-3-nitro-benzoic acid 1 (1.0 g, 3.84 mmol, 1.0 equiv) and 4-dimethylaminomethyl pyridine (DMAP) (0.020 g, 0.19 mmol, 0.05 equiv) in 10 mL of dichloromethane-methanol (10%) at room temperature. The mixture was stirred for 6 hours to obtain 4-bromomethyl-3-nitro-benzoic acid methyl ester 2. Dicyclohexyl urea (DCU) thus obtained was removed by filtration and the solvent in the filtered solution was removed under vacuum. The residue was purified by column chromatography using hexane-ethyl acetate (15%) as an eluant to give ester 2 as a light yellow oil.