反应详情

温度

70 °C

To a suspension of 4-acetyl-2-(fluoro)benzenesulfonamide from step1(4.0 g, 18 mmol) in acetic acid (90 mL) was added dropwise a solution of bromine (2.9 g, 18 mmol) in acetic acid (10 mL) at 40° C. The mixture was heated at 70° C. for 4 h. After cooled to room temperature, the mixture was concentrated and the residual brown solid was rrecrystallized from ethyl acetate-hexane to give the title compound (3.2 g, 60%).

1. temperatureAfter cooled to room temperature
2. concentrationthe mixture was concentrated