反应详情

温度

100 °C

To a stirred solution of 1-(5-chloro-2-methoxy-4-methylphenyl)ethanone (5.00 g, 25.2 mmol, from Oakwood) in acetic acid (100 mL) was added N-bromosuccinimide (4.93 g, 27.7 mmol) and the resulting mixture heated at 100° C. for 18 hours. After cooling to ambient temperature, the reaction mixture was concentrated in vacuo, then neutralized with sat. sodium bicarbonate, filtered off insoluble succinimide. The filtrate was extracted with EtOAc. The combined organic layers were washed with brine, dried over sodium sulfate, and then concentrated to dryness under reduced pressure. The residue was purified on silica gel, eluting with 0 to 50% EtOAc in hexanes, to give the desired products (2.66 g, 38%). LCMS calculated for C10H11BrClO2(M+H)+: m/z=277.0; found: 277.0. 1H NMR (DMSO-d6, 300 MHz): δ 7.70 (1H, s), 3.77 (3H, s), 2.57 (3H, s), 2.50 (3H, s) ppm.

1. temperatureAfter cooling to ambient temperature
2. concentrationthe reaction mixture was concentrated in vacuo
3. filtrationfiltered off insoluble succinimide
4. extractionThe filtrate was extracted with EtOAc
5. washThe combined organic layers were washed with brine
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated to dryness under reduced pressure
8. customThe residue was purified on silica gel
9. washeluting with 0 to 50% EtOAc in hexanes