反应详情

A mixture of 1-(5-chloro-2-thienyl)-2-(pyridin-4-yl)ethanone (0.68 mmol), secbutylhydrazin (1.37 mmol) and triethylamine (1.37 mmol) in 5 mL dichloromethane was refluxed for 2.5 h. The solvent was evaporated under reduced pressure and the residue was partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate and the combined organic extracts were dried over MgSO4 filtered and concentrated. The residue was purified by chromatography on silica gel (dichloromethane:methanol 100:1 to 20:1) to afford 37 mg of 4-[1-sec-butyl-3-(5-chloro-2-thienyl)-1H-pyrazol-4-yl]pyridine (16% yield) and 48 mg of 4-[1-sec-butyl-5-(5-chloro-2-thienyl)-1H-pyrazol-4-yl]pyridine (21% yield).

1. temperaturewas refluxed for 2.5 h
2. customThe solvent was evaporated under reduced pressure
3. customthe residue was partitioned between ethyl acetate and water
4. extractionThe aqueous layer was extracted with ethyl acetate
5. dry with materialthe combined organic extracts were dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was purified by chromatography on silica gel (dichloromethane:methanol 100:1 to 20:1)