反应详情

To a rapidly stirred solution of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-iodopyrazole (0.25 g) in toluene (2 ml) containing tetrakis(triphenylphosphine)palladium(0) (0.02 g) was added saturated aqueous sodium hydrogen carbonate solution (1 ml) and a solution of 4-pyridylboronic acid (0.153 g) in ethanol (1 ml). The mixture was heated under reflux for 12 hours, then left at room temperature overnight and then poured into ether (25 ml) and water (25 ml). The organic layer was separated, dried (MgSO4) and evaporated. The residue was taken up the minimum amount of ethyl acetate and purified by chromatography on silica gel (20 g) eluted with dichloromethane:methanol (100:1). Combination and evaporation of suitable fractions followed by recrystallisation from ether/hexane dichloromethane gave the title compound as a white solid, m.p. 226-8° C. (decomp.).

1. temperatureThe mixture was heated
2. temperatureunder reflux for 12 hours
3. customThe organic layer was separated
4. dry with materialdried (MgSO4)
5. customevaporated
6. custompurified by chromatography on silica gel (20 g)
7. washeluted with dichloromethane:methanol (100:1)
8. customCombination and evaporation of suitable fractions
9. customfollowed by recrystallisation from ether/hexane dichloromethane