反应详情

温度

-78 °C

To a solution of 2-fluoro-1,4-dimethoxybenzene (8.1 g, 52.0 mmol) in anhydrous THF at −78° C., n-BuLi (2.5 M in hexane, 22 mL, 55 mmol) was added dropwise. The resulting mixture was stirred at −78° C. for 1 h, and then ethyl chloroformate (5 mL, 52.1 mmol) was added dropwise. The reaction mixture was stirred at −78° C. for additional 2 h and quenched with water (200 mL). The mixture was extracted with ethyl acetate (2×180 mL). The combined organic layers were washed with brine (200 mL), dried (Na2SO4), and concentrated in vacuo. The residue was purified by silica gel column chromatography (1:5 EtOAc/petroleum ether) to give ethyl 2-fluoro-3,6-dimethoxybenzoate (8.1 g).

1. stirringThe reaction mixture was stirred at −78° C. for additional 2 h
2. customquenched with water (200 mL)
3. extractionThe mixture was extracted with ethyl acetate (2×180 mL)
4. washThe combined organic layers were washed with brine (200 mL)
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated in vacuo
7. customThe residue was purified by silica gel column chromatography (1:5 EtOAc/petroleum ether)