反应详情

温度

100 °C

A mixture of bromomaleic anhydride (50 g, 283 mmol) and sodium acetate (76.5 g, 562 mmol) in 40% acetic acid/water (750 ml) was treated with hydrazine monohydrate (16.5 ml, 339 mmol) at room temperature under nitrogen. The brown solution was stirred and heated at 100° C. for 18 hours. Upon cooling the mixture was poured into water (1 l) and extracted with ethyl acetate (6×500 ml). The combined extracts were dried (MgSO4), filtered and evaporated to afford the title compound (20 g, 37%) as an orange solid. 1H NMR (250 MHz, d6-DMSO) δ 7.68 (1H, br s). MS (ES+) m/e 193 [MH]+, 191 [MH]+. This material was used without further purification.

1. temperatureUpon cooling the mixture
2. extractionextracted with ethyl acetate (6×500 ml)
3. dry with materialThe combined extracts were dried (MgSO4)
4. filtrationfiltered
5. customevaporated