反应详情

5-Bromo-2-fluoroaniline (14.79 g, 78 mmol) was heated at reflux in acetic acid (50 ml) and acetic anhydride (50 ml) for 8 hours. The solution was concentrated in vacuo, azeotroping with toluene. The residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The organic phase was washed with water (×3), brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by chromatography on silica gel (gradient of hexane to ethyl acetate) to afford the title compound. MS (ES+) m/e 232/234 [M+H]+.

1. concentrationThe solution was concentrated in vacuo
2. customazeotroping with toluene
3. customThe residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution
4. washThe organic phase was washed with water (×3), brine
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was purified by chromatography on silica gel (gradient of hexane to ethyl acetate)