反应详情

5-chloro-3-(3-fluorophenyl)-2-methylquinoxaline (0.3907 g, 1.433 mmol) and 1,3-dibromo-5,5-dimethylhydantoin (0.2458 g, 0.8596 mmol) were suspended in carbon tetrachloride (14.33 mL, 1.433 mmol). To the mixture was added benzoyl peroxide (0.04627 g, 0.1433 mmol) and the mixture was heated at reflux. After 24 h, the mixture was cooled to room temperature and concentrated under reduced pressure. The residue was purified by silica gel column chromatography on a 40 g of Redi-Sep™ column using 0 to 9% gradient of EtOAc in hexane over 1.3 min, then 9% isocratic of EtOAc for 7.6 min, then 9 to 100% gradient of EtOAc in hexane over 12.7 min, then 100% isocratic of EtOAc for 10 min as eluent to give 2-(bromomethyl)-5-chloro-3-(3-fluorophenyl)quinoxaline as an off-white solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 8.14 (1H, dd, J=8.4, 1.2 Hz), 8.12 (1H, dd, J=7.6, 1.4 Hz), 7.92 (1H, dd, J=8.4, 7.8 Hz), 7.64-7.70 (3H, m), 7.43-7.50 (1H, m), 4.91 (2H, s); LC-MS (ESI) m/z 351.0 and 352.9 [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 40 g of Redi-Sep™ column
5. customover 1.3 min
6. wait9% isocratic of EtOAc for 7.6 min
7. wait9 to 100% gradient of EtOAc in hexane over 12.7 min