反应详情

5-Chloro-2-methyl-3-(2-(trifluoromethyl)phenyl)quinoxaline (1.4455 g, 4.479 mmol) and 1,3-dibromo-5,5-dimethylhydantoin (0.6404 g, 2.240 mmol) were suspended in carbon tetrachloride (44.79 mL, 4.479 mmol). To the mixture was added benzoyl peroxide (0.1447 g, 0.4479 mmol) and the mixture was heated at reflux. After 21.5 h, the mixture was cooled to room temperature and concentrated under reduced pressure. The residue was purified by silica gel column chromatography on a 80 g of Redi-Sep™ column using 0 to 9% gradient of EtOAc in hexane over 2 min, then 9% isocratic of EtOAc for 13 min, then 9 to 100% gradient of EtOAc in hexane over 23 min, then 100% isocratic of EtOAc for 4 min as eluent to give 2-(bromomethyl)-5-chloro-3-(2-(trifluoromethyl)-phenyl)quinoxaline as a yellow solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 8.18 (1 H, dd, J=8.4, 1.4 Hz), 8.13 (1 H, dd, J=7.8, 1.2 Hz), 7.81-8.03 (5 H, m), 4.69 (2 H, dd, J=88.4, 10.2 Hz); LC-MS (ESI) m/z 400.9 and 403.0 [M+H]+.

1. temperaturethe mixture was heated
2. temperatureat reflux
3. concentrationconcentrated under reduced pressure
4. customThe residue was purified by silica gel column chromatography on a 80 g of Redi-Sep™ column
5. customover 2 min
6. wait9% isocratic of EtOAc for 13 min
7. wait9 to 100% gradient of EtOAc in hexane over 23 min