反应详情

A solution of tert-butyl 4-[(6-hydroxy-3-oxo-2,3-dihydrobenzofuran-7-yl)methyl]piperazine-1-carboxylate (3.48 g, 10.0 mmol) in toluene (40 mL) was added with methanol (0.486 mL, 12.0 mmol), triphenylphosphine (3.93 g, 15.0 mmol) and a 40% solution of diethyl azodicarboxylate in toluene (6.53 g, 15.0 mmol), and the mixture was stirred at 110° C. for 5 hours. The reaction mixture was concentrated, and the resulting residue was purified by silica gel column chromatography (chloroform/ethyl acetate) to obtain tert-butyl 4-[(6-methoxy-3-oxo-2,3-dihydrobenzofuran-7-yl)methyl]piperazine-1-carboxylate (1.25 g, 34%).

1. concentrationThe reaction mixture was concentrated
2. customthe resulting residue was purified by silica gel column chromatography (chloroform/ethyl acetate)