反应详情

A mixture of 2-methoxy-6-methylpyridine (17.0 g, 138 mmol) and a solution of disodium hydrogen phosphate (0.15M in water, 250 mL) was stirred at room temperature. Bromine (7.1 mL, 138 mmol) was added dropwise over 15 min via an addition funnel. The reaction mixture was then stirred at room temperature for 4 h. The clear colorless solution was diluted with water (500 mL) and extracted with dichloromethane (200 mL) three times. The combined organic layers were dried over MgSO4, filtered and solvent was removed in vacuo from the filtrate to give a yellow liquid. Flash chromatography on silica gel (EtOAc:hexane::1:20) and removal of solvent from the desired combined fractions afforded a clear colorless liquid (15.4 g): 1H-NMR(CDCl3, 300 MHz): δ 7.60 (d, 1H, J=8), 6.46 (d, 1H, J=8), 3.89 (s, 3H), 2.54 (s, 3H).

1. extractionextracted with dichloromethane (200 mL) three times
2. dry with materialThe combined organic layers were dried over MgSO4
3. filtrationfiltered
4. customsolvent was removed in vacuo from the filtrate
5. customto give a yellow liquid
6. customFlash chromatography on silica gel (EtOAc:hexane::1:20) and removal of solvent from the