反应详情

温度

75 °C

A mixture of ethyl 5-chloro-2-methylbenzoate (3.20 g, 16.1 mmol), N-bromosuccinimide (3.15 g, 17.7 mmol) and benzoyl peroxide (0.39 g, 1.61 mmol) in 1,2-dichloroethane (90 mL) was heated to 75° C. in an oil bath for 4 h. After this time, the mixture was cooled to room temperature and the organic layer was washed with water (45 mL) and brine (45 mL). The organic layer was then dried over magnesium sulfate and concentrated under reduced pressure. Purification by flash chromatography (silica, 1:20 ethyl acetate/hexanes) afforded ethyl 2-(bromomethyl)-5-chlorobenzoate (3.09 g, 68%) as a clear oil: 1H NMR (500 MHz, CDC13) 7.94 (d, J=2.5 Hz, 1H), 7.46 (dd, J=8.5, 2.5 Hz, 1H), 7.40 (d, J=8.0 Hz, 1H), 4.91 (s, 2H), 4.42 (q, J=7.0 Hz, 2H), 1.43 (t, J=7.0 Hz, 3H); ESI MS m/z 279 [(M+2)+H]+.

1. temperatureAfter this time, the mixture was cooled to room temperature
2. washthe organic layer was washed with water (45 mL) and brine (45 mL)
3. dry with materialThe organic layer was then dried over magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customPurification by flash chromatography (silica, 1:20 ethyl acetate/hexanes)