反应详情

温度

110 °C

70 ml of acetic anhydride was added to 7.61 g of 4-chloro-3-difluoromethyl-2-methylpyridine N-oxide (VI), which was heated at 110° C. for 1 hour. The solvent was distilled off under reduced pressure, and thereafter, saturated aqueous sodium bicarbonate solution was added thereto and the resulting mixture was extracted with ether. The resulting organic layer was washed with saturated salt water, and thereafter, dried over anhydrous sodium sulfate and the solvent was distilled off under reduced pressure. The resulting residue was dissolved in 90% ethanol and 2.36 g of sodium hydroxide was added thereto and the resulting mixture was heated at 80° C. for 2 hours. The solvent was distilled off under reduced pressure, and thereafter, water was added thereto and the resulting mixture was extracted with chloroform. The resulting organic layer was washed with saturated salt water, and thereafter, dried over anhydrous sodium sulfate and the solvent was distilled off under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent; chlorohorm) to obtain 1.55 g of 4-chloro-3-difluoromethyl-2-hydroxymethylpyridine (VII).

1. distillationThe solvent was distilled off under reduced pressure
2. additionsaturated aqueous sodium bicarbonate solution was added
3. extractionthe resulting mixture was extracted with ether
4. washThe resulting organic layer was washed with saturated salt water
5. dry with materialdried over anhydrous sodium sulfate
6. distillationthe solvent was distilled off under reduced pressure
7. dissolutionThe resulting residue was dissolved in 90% ethanol
8. addition2.36 g of sodium hydroxide was added
9. temperaturethe resulting mixture was heated at 80° C. for 2 hours
10. distillationThe solvent was distilled off under reduced pressure
11. additionwater was added
12. extractionthe resulting mixture was extracted with chloroform
13. washThe resulting organic layer was washed with saturated salt water
14. dry with materialdried over anhydrous sodium sulfate
15. distillationthe solvent was distilled off under reduced pressure
16. customThe resulting residue was purified by silica gel column chromatography (eluent; chlorohorm)