反应详情

In a fashion similar to that for preparation 15, 2,4-difluorobenzoyl chloride oxime (2.00 g, 10.4 mmol), ethyl 2-butynoate (1.76 g, 15.7 mmol), triethyl amine (2.9 ml, 21 mmol) in diethyl ether (10 ml), and diethyl ether 30 ml) gave 4-ethoxycarbonyl-5-methyl-3-(2,4-difluorophenyl)isoxazole (1.62 g, 58%) after column chromatography (silica gel, hexanes/diethyl ether gradient).