反应详情

Dissolve 3-bromo-5-ethylaniline (4.7g, 23.5mmol) in methanol (100mL) and add diethylacetylene dicarboxylate (5.5mL) at room temperature. Reflux for 10 hours and cool to room temperature. Evaporate the solvent in vacuo and add to diphenylether (100mL) at 250° C. Stir for 15 minutes and let cool to room temperature. Add hexane (500mL) and filter the precipitate. Purify by silica gel chromatography to give 5-ethyl-7-bromo-4-oxo-1,4-dihydroquinoline-2-carboxylic acid, ethyl ester

1. temperatureReflux for 10 hours
2. customEvaporate the solvent in vacuo
3. additionadd to diphenylether (100mL) at 250° C
4. temperaturelet cool to room temperature
5. filtrationAdd hexane (500mL) and filter the precipitate
6. customPurify by silica gel chromatography