反应详情

A stirred solution of 4,4-dimethoxy-1-pyridin-4-yl-butane-1,3-dione (20 g, Reference Example 2) in ethanol (500 ml) was treated with 4-fluorophenylhydrazine hydrochloride (29 g). The mixture was refluxed for 0.5 hour then evaporated. The residual yellow oil was subjected to flash chromatography on silica eluting with a mixture of methanol and dichloromethane (99:1, v/v) to give the title compound as a brown oil (2.7 g). MS: 314 [MH]+. RF=0.27 (ethyl acetate, determined by thin layer chromatography on silica).

1. temperatureThe mixture was refluxed for 0.5 hour
2. customthen evaporated
3. additionThe residual yellow oil was subjected to flash chromatography on silica eluting with a mixture of methanol and dichloromethane (99:1