反应详情

3.0 g (12.9 mmol) of ethyl 1-methyl-2-oxo-1,2-dihydroquinoxaline-3-carboxylate was dissolved in ethanol (100 mL), and 4.1 g (25.6 mmol) of a 25% aqueous solution of sodium hydroxide was added dropwise thereto at room temperature. The mixture was stirred for a day at room temperature, and then the reaction mixture was concentrated under reduced pressure. Water was added to the reaction mixture, and the solution was acidified using 10% hydrochloric acid, and extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate, and then the inorganic matter was separated by filtration. Then, the solvent was distilled off under reduced pressure, to obtain 2.6 g (yield: 99%) of 1-methyl-2-oxo-1,2-dihydroquinoxaline-3-carboxylic acid as a milky yellow powder.

1. customat room temperature
2. concentrationthe reaction mixture was concentrated under reduced pressure
3. additionWater was added to the reaction mixture
4. extractionextracted with chloroform
5. dry with materialThe organic layer was dried over anhydrous sodium sulfate
6. customthe inorganic matter was separated by filtration
7. distillationThen, the solvent was distilled off under reduced pressure