反应详情

A mixture of 2.2 g of 3-amino-5-(4-phenylmethyl-1-piperazinyl)-4-pyrazolecarbonitrile (Example 1) and 1.37 g of 3-dimethylamino-1-(4-pyridyl)-2-propen-1-one U.S. Pat. No. 4,281,000, Example 63) in 25 ml of glacial acetic acid was refluxed for 6 hours. The solution was taken to dryness in vacuo. The residue was partitioned between saturated sodium bicarbonate and dichloromethane (1:2). The dichloromethane layer was separated, dried over anhydrous sodium sulfate and filtered through a short column of magnesium silicate. The effluent was refluxed on a steam bath with the gradual addition of hexane until turbidity was noted. After cooling, the precipitate was collected by filtration. The solid was recrystallized from dichloromethane/hexane and gave 1.65 g of the product of the Example as very pale yellow crystals, mp 193°-194° C.

1. customThe residue was partitioned between saturated sodium bicarbonate and dichloromethane (1:2)
2. customThe dichloromethane layer was separated
3. dry with materialdried over anhydrous sodium sulfate
4. filtrationfiltered through a short column of magnesium silicate
5. temperatureThe effluent was refluxed on a steam bath with the gradual addition of hexane until turbidity
6. temperatureAfter cooling
7. filtrationthe precipitate was collected by filtration
8. customThe solid was recrystallized from dichloromethane/hexane