反应详情

A solution of 2-amino-5-nitrophenol (97, 24 g, 156 mmol) in CH3CN (1 L) was treated with NBS (28.8 g, 160.8 mmol) at room temperature. After stirring for 1 hour, the solvent was removed to afford brown precipitate, which was taken up with ethyl acetate:hexane (1:1). The precipitate was filtered and was used for the next step without further purification (33 g, 91%). A small amount of sample was purified by column chromatography on silica gel for analysis; 1H NMR (500 MHz, CD3OD): δ 4.93 (brs, 3H), 7.50 (d, 1H, J=2.4 Hz), 7.89 (d, 1H, J=2.4 Hz); 13C NMR (125 MHz, CD3OD): δ 105.5, 108.7, 121.8, 138.5, 143.7, 144.8; HRMS (FAB) calcd for C6H5BrN2O3(M+) 231.9484. found 231.9479.

1. customthe solvent was removed
2. customto afford brown precipitate, which
3. filtrationThe precipitate was filtered
4. customwas used for the next step without further purification (33 g, 91%)
5. customA small amount of sample was purified by column chromatography on silica gel for analysis