反应详情

To a solution of 1-bromo-2-methyl-3-(trifluoromethyl)benzene (CXXVII) (5.7 g, 23.86 mmol) in CCl4 (50 mL) was added NBS (4.24 g, 23.86 mmol) and a catalytic amount of benzoyl peroxide. The reaction mixture was gently refluxed for 1 h. The reaction mixture was cooled to room temperature and the precipitate was removed by filtration. The solution was concentrated under reduced pressure and the crude product was dissolved in hexane and additional precipitate was removed by filtration. The filtrate was concentrated to dryness to give 1-bromo-2-(bromomethyl)-3-(trifluoromethyl)benzene (CXXVIII) as an orange oil (7.51 g, 23.62 mmol). 1H NMR (DMSO-d6) δ ppm 4.73 (s, 2H), 7.4 (dd, J=8 Hz, J=8 Hz, 1H), 7.80 (d, J=8 Hz, 1H), 8.02 (d, J=8 Hz, 1H); 19F NMR (DMSO-d6) δ ppm −57.85 (s, 3F). The crude product was used without further purification for step 2.

1. temperatureThe reaction mixture was gently refluxed for 1 h
2. customthe precipitate was removed by filtration
3. concentrationThe solution was concentrated under reduced pressure
4. dissolutionthe crude product was dissolved in hexane
5. customadditional precipitate was removed by filtration
6. concentrationThe filtrate was concentrated to dryness