反应详情

温度

5 °C

2-Bromo-3-methylanisole (2.02 g, 1.00 mmol) and N-bromosuccinimide in carbon tetrachloride (25 ml) were heated to reflux over a 150 W light bulb for 2 h. The solution was cooled to 5° C., filtered and evaporated to drynes under reduced pressure. Purification by flash chromatography using hexane/dichloromethane (8:1) as eluent gave the title compound (162 g, 58%) as a white low melting point solid; δH (CDCl3) 3.90 (3H, s, OCH3), 4.64 (2H, s, CH2Br), 6.85 (1H, dd, J 8.2 and 1.3 Hz, 6-H), 7.08 (1H, dd, J 7.5 and 1.3 Hz, 4-H9, 7.23-7.30 (1H, m, 5-H): δC (CDCl3) 33.7 (CH2Br), 56.4 (OCH3), 111.8, 114.1 (C-2), 123.1, 128.3, 138.6 (C-1), 156.4 (C-3): m/z 282 (M+, 12%), 280 (M+, 13%). 199 (100%): (Found: M+, 277.8947. C8H8OBr2 requires M, 277.8942).

1. temperatureto reflux over a 150 W light bulb for 2 h
2. filtrationfiltered
3. customevaporated to drynes under reduced pressure
4. customPurification by flash chromatography