反应详情

温度

25 °C

To a suspension of 2-ethoxycarbonyl-1-methyl-7-trifluoromethylimidazo[1,2-a]quinoxalin-4(5H)-one (Example 1) (88 g, 259 mmol) in DMF (1.5 l) was dropwise added a solution of 28% phosgene in toluene (0.5 l, 960 mmol). The mixture was stirred at 50° C. for 1 h and overnight at 25° C. followed by evaporation in vacuo. The residue was stirred with ice-cooled water. The solid was collected by filtration and washed with water to yield 83,4 g (95%) of 4-chloro-2-ethoxycarbonyl-1-methyl-7trifluoromethylimidazo[1,2-a]quinoxaline. M.p. 182°-183° C.

1. customfollowed by evaporation in vacuo
2. stirringThe residue was stirred with ice-
3. temperaturecooled water
4. filtrationThe solid was collected by filtration
5. washwashed with water