反应详情

温度

28 °C

At 15° C.,9.5 g (0.03 mole) 4-bromo-3-(2,5-difluorophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazole was slowly added to 100 mL of fuming nitric acid. The reaction warmed to 28° C. over a period of 20 minutes. The reaction mixture was stirred at 30° C. for 4 hours. The mixture was poured into 500 mL of ice. After stirring for 1 hour, the slurry was extracted 3 times with methylene chloride. The methylene chloride extracts were washed with water, dried over anhydrous MgSO4, and concentrated in vacuo. The residue was purified chroma-tographically using 10% ethyl acetate in hexane as the eluent to give 5.84 g (55%) of 4-bromo-3-(2,5-difluoro-4-nitrophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazole as a white solid, mp 45.5° C.

1. stirringAfter stirring for 1 hour
2. extractionthe slurry was extracted 3 times with methylene chloride
3. washThe methylene chloride extracts were washed with water
4. dry with materialdried over anhydrous MgSO4
5. concentrationconcentrated in vacuo
6. customThe residue was purified chroma-tographically