反应详情

10.5 g (73.6 mmol) of 3-chloro-1,2-phenylenediamine and 12.8 g (73.5 mmol) of diethyl ketomalonate were dissolved in ethanol, and the solution was heated to reflux for 3 hours. While heating to reflux, ethanol was added thereto until precipitated crystals dissolved. The reaction mixture was cooled to room temperature, and then precipitated crystals were separated by filtration. The filter cake was washed with cold ethanol, and then dried, to obtain 10.5 g (yield: 51%) of ethyl 5-chloro-2-oxo-1,2-dihydroquinoxaline-3-carboxylate as pale yellow acicular crystals.

1. temperaturethe solution was heated
2. temperatureto reflux for 3 hours
3. temperatureWhile heating
4. temperatureto reflux
5. customuntil precipitated crystals
6. dissolutiondissolved
7. customprecipitated crystals
8. customwere separated by filtration
9. washThe filter cake was washed with cold ethanol
10. customdried