反应详情

To a stirred solution of 2-fluoro-3-methylbenzoic acid (4.0 g, 26.0 mmol) in anhydrous methanol (52 mL) at 0° C. was added thionyl chloride (2.8 mL, 39.0 mmol) dropwise and the reaction mixture was stirred overnight at reflux. The mixture was diluted with methanol and concentrated under reduced pressure to remove the excess thionyl chloride. The residue was then dissolved in ethyl acetate, washed with saturated aqueous sodium bicarbonate, dried (Na2SO4), filtered, and concentrated under reduced pressure to give methyl 2-fluoro-3-methylbenzoate (3.6 g, 83%) as a clear oil that was used in the next step without further purification: 1H NMR (500 MHz, CDCl3) δ 7.75-7.72 (m, 1H), 7.38-7.35 (m, 1H), 7.26-7.06 (m, 1H), 3.91 (s, 3H), 2.31 (s, 3H).

1. temperatureat reflux
2. concentrationconcentrated under reduced pressure
3. customto remove the excess thionyl chloride
4. dissolutionThe residue was then dissolved in ethyl acetate
5. washwashed with saturated aqueous sodium bicarbonate
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure