反应详情

To a suspension of N,O-dimethylhydroxylamine hydrochloride (703 mg, 7.21 mmol) in ethanol (5.4 ml) and water (0.6 ml) was added triethylamine (729 mg, 1.00 ml, 7.21 mmol) and the mixture was stirred for 10 min at room temperature. Then 8-fluoro-1H-benzo[d][1,3]oxazine-2,4-dione (870 mg, 4.8 mmol) and additional ethanol (2 ml) were added and the reaction mixture was heated to reflux for 3.5 h. After cooling to room temperature, the mixture was poured onto ice/saturated NaHCO3-solution, extracted with EtOAc and the combined extracts were washed with water and brine, dried with Na2SO4 and evaporated. The remaining residue was purified by column chromatography (silica gel, heptane/EtOAc 80:20-70:30) to afford the title compound (765 mg, 80%) as light brown oil. MS (ESI): 199.2 (M+H)+.

1. temperaturethe reaction mixture was heated
2. temperatureto reflux for 3.5 h
3. temperatureAfter cooling to room temperature
4. additionthe mixture was poured onto ice/saturated NaHCO3-solution
5. extractionextracted with EtOAc
6. washthe combined extracts were washed with water and brine
7. dry with materialdried with Na2SO4
8. customevaporated
9. customThe remaining residue was purified by column chromatography (silica gel, heptane/EtOAc 80:20-70:30)