反应详情

温度

0 °C

20.6 g (68 mmol) of 7-acetamido-1-cyclohexyl-2,3(1H,4H)-quinoxalinedione were dissolved in 250 ml of concentrated sulfuric acid. Then, at 0°-5° C., 7.2 g (71 mmol) of potassium nitrate were added a little at a time. The mixture was then stirred at 0° C. for 30 min and at room temperature for 2 h and subsequently poured into 1.5 1 of ice-water and then heated on a water bath for 4 h. The resulting precipitate was filtered off with suction. The filtrate was adjusted to pH 6 with a little ammonia solution and was extracted with methylene chloride. The organic phase was dried and concentrated under reduced pressure. This residue and the first precipitate were combined to yield 13.4 g (64%) of the product. Melting point>260° C.

1. temperatureheated on a water bath for 4 h
2. filtrationThe resulting precipitate was filtered off with suction
3. extractionwas extracted with methylene chloride
4. customThe organic phase was dried
5. concentrationconcentrated under reduced pressure