反应详情

To a solution of 5,6-dimethyl-1,4dihydro-quinoxaline-2,3-dione (28.5 g, 150 mmol) in concentrated H2SO4 (50 mL) was added KNO3 (15.15 g, 150 mmol) portionwise keeping temperature below 5° C. Reaction mixture was stirred for 2 hours and poured over ice. Yellow precipitate was filtered, washed, and air dried.

1. customtemperature below 5° C
2. customReaction mixture
3. additionpoured over ice
4. filtrationYellow precipitate was filtered
5. washwashed
6. customair dried