反应详情

Potassium carbonate (4.10 g, 29.7 mmol) was added to a solution of 2-chloro-N-(2-hydroxy-3-nitrophenyl)acetamide obtained (5.70 g, 24.7 mmol) in N,N-dimethylformamide (150 mL) while cooling in ice, and the mixture was stirred at room temperature for 5 hr. The mixture was diluted with ethyl acetate, washed with water and brine, and then dried over anhydrous sodium sulfate. The desiccant was filtered off, followed by concentration under reduced pressure. The resulting residue was powdered with chloroform and collected by filtration to afford 8-nitro-2 H-1,4-benzoxazin-3(4 H)-one as a pale orange powder (4.32 g).

1. temperaturewhile cooling in ice
2. washwashed with water and brine
3. dry with materialdried over anhydrous sodium sulfate
4. filtrationThe desiccant was filtered off
5. concentrationfollowed by concentration under reduced pressure
6. filtrationcollected by filtration