反应详情

温度

2.5 °C

To a solution of 3-fluoro-4-nitroaniline (56 g, 0.36 mol) in acetic acid (500 mL) was added drop-wise bromine (17.7 mL, 0.36 mol) over 1 hour. The reaction mixture was stirred for 1 hour at 0-5° C. in an ice bath. The reaction mixture was basified with saturated Na2CO3 and extracted with ethyl acetate (200 mL×3). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to yield a residue that was purified by column chromatography on silica gel (petroleum ether/ethyl acetate 10:1) to give the 2-bromo-5-fluoro-4-nitroaniline (45.6 g, 84%) as a yellow solid. 1H NMR (400 MHz, CDCl3) δ 8.29 (d, J=7.6 Hz, 1H), 653 (d, J=12.4 Hz, 1H), 4.94 (br s, 2H).

1. extractionextracted with ethyl acetate (200 mL×3)
2. washThe combined organic layers were washed with brine
3. dry with materialdried over anhydrous Na2SO4
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customto yield a residue that
7. customwas purified by column chromatography on silica gel (petroleum ether/ethyl acetate 10:1)