反应详情

温度

5 °C

To a solution of 1-bromo-2-fluoro-4-methyl-5-(2,2,2-trichloro-ethyl)-benzene (29.2 g) in methanol (100 ml) was added a sodium methoxide solution (30% in methanol, 78.2 ml) dropwise. The reaction mixture was stirred at reflux for 24 hours, cooled to 5° C. and treated with concentrated sulfuric acid (13.2 ml) dropwise. After further warming to reflux for 21 hours, the mixture was concentrated and the residue diluted with water/ethyl acetate. The aqueous layer was extracted with ethyl acetate, the combined organic layers were washed with brine, dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica gel (ethyl acetate/cyclohexane 1:3). Yield: 18.76 g of (5-bromo-4-fluoro-2-methyl-phenyl)-acetic acid methyl ester as an oil.

1. temperatureat reflux for 24 hours
2. temperatureAfter further warming
3. temperatureto reflux for 21 hours
4. concentrationthe mixture was concentrated
5. additionthe residue diluted with water/ethyl acetate
6. extractionThe aqueous layer was extracted with ethyl acetate
7. washthe combined organic layers were washed with brine
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated
10. customThe residue was purified by chromatography on silica gel (ethyl acetate/cyclohexane 1:3)