反应详情

A 10-mL single-neck round-bottomed flask equipped with a magnetic stirrer and nitrogen inlet was purged with nitrogen and charged with 1-methyl-5-(2-methyl-3-nitrophenyl)pyridin-2-one (10) (0.60 mg, 2.46 mmol) and glacial acetic acid (5 mL). To the resulting solution bromine (0.59 g, 3.70 mmol) was added. The reaction was stirred for 18 h at room temperature. After this time the reaction was partitioned between water (25 mL) and ethyl acetate (75 mL). The organic layer was separated and washed with saturated aqueous sodium bicarbonate (2×25 mL), brine (50 mL) and dried over magnesium sulfate. The drying agent was removed by filtration and the filtrate concentrated to a constant weight under reduced pressure to afford 0.075 g (93%) of 3-bromo-1-methyl-5-(2-methyl-3-nitrophenyl)pyridin-2-one (11) as a yellow oil: 1H NMR (300 MHz, CDCl3) 7.83 (dd, 1H, J=7.2, 2.1 Hz), 7.75 (d, 1H, J=2.4 Hz), 7.42 (dd, 1H, J=7.8, 2.4 Hz), 7.38 (t, 1H, J=7.5 Hz), 7.29 (d, 1H, J=2.4 Hz), 3.70 (s, 3H), 2.40 (s, 3H); MS (ESI+) m/z 323 (M+H).

1. customA 10-mL single-neck round-bottomed flask equipped with a magnetic stirrer and nitrogen inlet
2. customwas purged with nitrogen
3. customAfter this time the reaction was partitioned between water (25 mL) and ethyl acetate (75 mL)
4. customThe organic layer was separated
5. washwashed with saturated aqueous sodium bicarbonate (2×25 mL), brine (50 mL)
6. dry with materialdried over magnesium sulfate
7. customThe drying agent was removed by filtration
8. concentrationthe filtrate concentrated to a constant weight under reduced pressure