反应详情

To a mixture of 3-fluoro-4-nitroaniline (6.5 g, 42.2 mmol) in AcOH (80 mL) and chloroform (25 mL) was added dropwise Br2 (2.15 mL, 42.2 mmol) at 0° C. After addition, the resulting mixture was stirred at room temperature for 2 h and then poured into ice water. The mixture was basified with aqueous NaOH (10%) to pH˜8.0-9.0 under cooling and then extracted with EtOAc (50 mL×3). The combined organic layers were washed with water (80 mL×2) and brine (100 mL), dried over Na2SO4 and concentrated under reduced pressure to give 2-bromo-5-fluoro-4-nitroaniline (9 g, 90%). 1H-NMR (400 MHz, DMSO-d5) δ 8.26 (d, J=8.0, Hz, 1H), 7.07 (brs, 2H), 6.62 (d, J=9.6 Hz, 1H).

1. additionAfter addition
2. temperatureunder cooling
3. extractionextracted with EtOAc (50 mL×3)
4. washThe combined organic layers were washed with water (80 mL×2) and brine (100 mL)
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under reduced pressure