反应详情

Iron powder (5.6 g) was suspended in 5% acetic acid (112 g), and a solution of 2,4-dinitro-5-fluorophenoxyacetonitrile (2.4 g) in acetic acid (48 g) was dropwise added thereto under reflux, followed by refluxing for an additional 1 hour. The reaction mixture was filtered, and the filtrate was extracted with ethyl acetate. The extract was concentrated, and the precipitated crystals were collected by filtration and washed with a mixture of hexane and ether to give 7-fluoro-6-amino-2H-1,4-benzoxazin-3-(4H)-one (1.3 g; yield, 71.7%).

1. temperatureunder reflux
2. temperatureby refluxing for an additional 1 hour
3. filtrationThe reaction mixture was filtered
4. extractionthe filtrate was extracted with ethyl acetate
5. concentrationThe extract was concentrated
6. filtrationthe precipitated crystals were collected by filtration
7. washwashed with a mixture of hexane and ether