反应详情

温度

20 °C

To a solution of 5-bromo-N,2-dimethoxy-N-methylnicotinamide (5.0 g, 18.18 mmol) in THF (50 mL), MeMgBr (10 mL, 30.0 mmol) was added dropwise at −78° C. The reaction mixture was stirred at 20° C. overnight. Then the reaction mixture was added to NH4Cl solution. The mixture was extracted with EtOAc. The combined organic phases were washed with brine, dried over Na2SO4, filtered and concentrated in vacuo. The crude product was purified using column chromatography (eluted with petroleum ether:EtOAc=10:1) to provide 1-(5-bromo-2-methoxypyridin-3-yl)ethanone (3.0 g, yield: 71%). 1H-NMR (CDCl3, 400 MHz) δ 8.33 (d, J=2.4 Hz, 1H), 8.19 (d, J=2.4 Hz, 1H), 4.03 (s, 3H), 2.63 (s, 3H). MS (M+H)+: 230/232

1. extractionThe mixture was extracted with EtOAc
2. washThe combined organic phases were washed with brine
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe crude product was purified
7. washcolumn chromatography (eluted with petroleum ether:EtOAc=10:1)