反应详情

温度

60 °C

A mixture of dry sulpholane (15 ml) and 4Å molecular sieve (3.0 g) was stirred under nitrogen with caesium fluoride (2.4 g) at 60° C. for ½ hour. To this was added 5-bromo-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethanesulphonylpyrazole (2.0 g) and the mixture stirred at 60° C. for 2 hours, and left overnight at room temperature. This was diluted with ether (50 ml), filtered, and washed with water (100 ml). The aqueous layer was re-extracted with ether (3×50 ml) and the combined organic solution re-washed with water (4×50 ml), dried over anhydrous magnesium sulphate, and evaporated in vacuo to give an oil. Purification by chromatography, eluting with ether/hexane (1:4) gave 3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-5-fluoro-4-trifluoromethanesulphonylpyrazole (0.17 g), m.p. 95-98° C., in the form of a white solid, after recrystallisation from hexane.

1. waitleft overnight at room temperature
2. filtrationfiltered
3. washwashed with water (100 ml)
4. extractionThe aqueous layer was re-extracted with ether (3×50 ml)
5. washthe combined organic solution re-washed with water (4×50 ml)
6. dry with materialdried over anhydrous magnesium sulphate
7. customevaporated in vacuo
8. customto give an oil
9. customPurification by chromatography
10. washeluting with ether/hexane (1:4)