6-BROMO-4-CHLOROQUINOLINE

145369-94-4

65340-70-7

4.1.8 Synthesis of 6-bromo-4-chloroquinoline (11) To a 100 mL round bottom flask were sequentially added 6-bromo-4-hydroxyquinoline (10) (3.0 g, 13.45 mmol), phosphorus trichloride (20 mL) and N,N-dimethylformamide (0.5 mL). The reaction mixture was heated to reflux and stirred for 6 hours. After completion of the reaction, it was cooled to room temperature and the reaction mixture was slowly poured into ice water (100 mL) and stirring was continued for 1 hour. Subsequently, the pH of the mixture was adjusted with saturated aqueous sodium bicarbonate solution to 8. The reaction mixture was extracted with ethyl acetate, the organic phases were combined and dried with anhydrous sodium sulfate. The organic phase was concentrated under reduced pressure to give the title compound 6-bromo-4-chloroquinoline (11) (2.75 g, 11.36 mmol, 84% yield) as a white solid. 1H NMR (500 MHz, DMSO-d6) δ 8.87 (d, J = 4.5 Hz, 1H, Ar-H), 8.32 (d, J = 2.0 Hz, 1H, Ar-H), 8.03 (d, J = 9.0 Hz, 1H, Ar-H), 7.99 (dd, J = 9.0, 2.0 Hz, 1H, Ar-H), 7.82 (d, J = 4.5 Hz, 1H, Ar-H). ESI-MS: m/z = 242 [M + H]+.