反应详情

A mixture of 5-chloro-1-methyl-3-trifluoromethylpyrazole-4-carboxylic acid (2.0 g), 4-fluorothiophenol (1.66 g) and anhydrous potassium carbonate (3.26 g) was heated under reflux in acetonitrile with stirring for 4 hours. After filtration the filtrate was evaporated, acidified with dilute hydrochloric acid and extracted with ethyl acetate. The combined extract was dried (anydrous magnesium sulphate), filtered and evaporated in vacuo. Recrystallisation from ether/hexane gave 5-(4-fluorophenylthio)-1-methyl-3-trifluoromethylpyrazole-4-carboxylic acid (0.98 g) m.p. 190°-193.7° C. as a white solid.

1. temperaturewas heated
2. filtrationAfter filtration the filtrate
3. customwas evaporated
4. extractionextracted with ethyl acetate
5. extractionThe combined extract
6. dry with materialwas dried (anydrous magnesium sulphate)
7. filtrationfiltered
8. customevaporated in vacuo
9. customRecrystallisation from ether/hexane