反应详情

To a 500 ml three neck flask provided with a stirrer, thermometer, and cooling tube were added 20.0 g (76.7 mmol) of 2,6-difluoro-4-bromobenzotrifluoride, 12.9 g (222.9 mmol) of potassium hydroxide, and 100 ml of ethanol, and heated to reflux while being stirred for 4 hours. After unreacted ethanol was distilled off under a reduced pressure from the reaction mixture, 200 ml of water was added thereto and extracted with 200 ml of diethyl ether. The extract was washed with water (150 ml) thrice and then dried over anhydrous magnesium sulfate. The colorless oily product in an amount of 20.5 g which was obtained by distilling off the solvent was purified by silica gel column chromatography (eluent: heptane) to obtain 18.7 g of colorless oily 2-fluoro-4-bromo-6-ethoxybenzotrifluoride.

1. temperaturethermometer, and cooling tube
2. temperatureheated
3. temperatureto reflux
4. distillationAfter unreacted ethanol was distilled off under a reduced pressure from the reaction mixture, 200 ml of water
5. additionwas added
6. extractionextracted with 200 ml of diethyl ether
7. washThe extract was washed with water (150 ml) thrice
8. dry with materialdried over anhydrous magnesium sulfate
9. customThe colorless oily product in an amount of 20.5 g which was obtained
10. distillationby distilling off the solvent
11. customwas purified by silica gel column chromatography (eluent: heptane)