反应详情

To a suspension of 2-bromo-4-methylbenzamide (14.8 g, 69.1 mmol) in CHCl3 was added phosphorous pentoxide (24.5 g, 172.8 mmol) and the mixture keep refluxing for 12 h. The reaction was allowed to cool to room temperature, and put into the ice water under the condition of stirring. The organic layer was separated and the aqueous layer was extracted with CHCl3 (150 mL×2). The combined organic phase was washed with brine, and dried over Na2SO4. Evaporation of the solvent afforded the title compound, 2-bromo-4-methylbenzonitrile (13.3 g, 98%). 1H NMR (400 MHz, CDCl3): δ 2.41 (s, 3 H), 7.20 (d, J=8.0 Hz, 1 H), 7.51-7.54 (m, 2 H).

1. temperaturethe mixture keep refluxing for 12 h
2. customThe organic layer was separated
3. extractionthe aqueous layer was extracted with CHCl3 (150 mL×2)
4. washThe combined organic phase was washed with brine
5. dry with materialdried over Na2SO4
6. customEvaporation of the solvent