4-Bromo-2-methylquinoline

(4a) 4-Hydroxy-2-methylquinoline (17.4 g, 109 mmol) and phosphorus oxytribromide (47.1 g, 164 mmol) were added to a round-bottom flask. The mixture was heated to 130° C. for several hours. After cooling to rt, the residue was partitioned between saturated Na2CO3 and ethyl acetate. The organic layer was separated and the aqueous layer was extracted with ethyl acetate (5.x.300 mL). The combined organic layer was washed with H2O (2.x.400 mL) and brine (1.x.400 mL) and dried over MgSO4. After filtration and concentration, the residue was purified on silica gel to provide 4-bromo-2-methylquinoline (8.8 g, 36percent).2-Methylquinolin-4-ol (4.46 g, 28.0 mmol) and N, N-dimethylformamide (80 mL) were added to a 250 mL single-neck flask, then to the mixture in flask was added dropwise phosphorus tribromide (11.37 g, 42 mmol) at 0 °C. After the addition, the reaction mixture was stirred at rt for 3 h. To the reaction mixture was added ice-water (100 mL) and ammonium hydroxide (100 mL, 25percent), then the resulting mixture was extracted with ethyl acetate (100 mL x 2). The combined organic layers were washed with saturated brine (100 mL), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated in vacuo. The residue was purified by silica-gel column chromatography (ethyl acetate/petroleum ether (v/v) = 1/10) to give the title compound as light yellow liquid (0.995 g, 16percent).MS (ES-API, pos. ion) m/z: 222.9 [M + 2]tGeneral procedure: To a stirred solution of the appropriate azine N-oxides in anhydrous CH(4a) 4-Hydroxy-2-methylquinoline (17.4 g, 109 mmol) and phosphorus oxytribromide (47.1 g, 164 mmol) were added to a round-bottom flask. The mixture was heated to 130° C. for several hours. After cooling to rt, the residue was partitioned between saturated Na2CO3 and ethyl acetate. The organic layer was separated and the aqueous layer was extracted with ethyl acetate (5.x.300 mL). The combined organic layer was washed with H2O (2.x.400 mL) and brine (1.x.400 mL) and dried over MgSO4. After filtration and concentration, the residue was purified on silica gel to provide 4-bromo-2-methylquinoline (8.8 g, 36percent).2-Methylquinolin-4-ol (4.46 g, 28.0 mmol) and N, N-dimethylformamide (80 mL) were added to a 250 mL single-neck flask, then to the mixture in flask was added dropwise phosphorus tribromide (11.37 g, 42 mmol) at 0 °C. After the addition, the reaction mixture was stirred at rt for 3 h. To the reaction mixture was added ice-water (100 mL) and ammonium hydroxide (100 mL, 25percent), then the resulting mixture was extracted with ethyl acetate (100 mL x 2). The combined organic layers were washed with saturated brine (100 mL), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated in vacuo. The residue was purified by silica-gel column chromatography (ethyl acetate/petroleum ether (v/v) = 1/10) to give the title compound as light yellow liquid (0.995 g, 16percent).MS (ES-API, pos. ion) m/z: 222.9 [M + 2]tGeneral procedure: To a stirred solution of the appropriate azine N-oxides in anhydrous CH

Molecular Weight:222.08
XLogP3:3.5
Hydrogen Bond Acceptor Count:1
Exact Mass:220.98401
Monoisotopic Mass:220.98401
Topological Polar Surface Area:12.9
Heavy Atom Count:12
Complexity:160
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes