反应详情

A mixture of 4-oxo-4-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)butyric acid (1.71 g), hydrazine monohydrate (1.46 g) and ethanol (17 ml) was heated under reflux for 1 hour. Ethanol was evaporated in vacuo. Water (20 ml) was added to the residue, acidified with 5% hydrochloric acid and extracted with chloroform (25 ml×3). The combined extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and evaporated in vacuo. The residue was recrystallized from ethanol to give crystals of 3-(3-oxo-2,3,4,5-tetrahydropyridazin-6-yl)-2-phenylpyrazolo[1,5-a]pyridine (1.19 g).

1. temperaturewas heated
2. temperatureunder reflux for 1 hour
3. customEthanol was evaporated in vacuo
4. additionWater (20 ml) was added to the residue
5. extractionextracted with chloroform (25 ml×3)
6. extractionThe combined extract
7. washwas washed with a saturated aqueous solution of sodium chloride
8. dry with materialdried over magnesium sulfate
9. customevaporated in vacuo
10. customThe residue was recrystallized from ethanol