反应详情

To a 20.0 g amount of 7-(3-(trifluoromethyl)-phenyl)pyrazolo(1,5-a)pyrimidine-3-carboxylic acid, ethyl ester (U.S. Pat. No. 4,178,449, Example 16) stirred in 100 ml of glacial acetic acid and cooled in a water bath is added portionwise 10.0 g of sodium cyanoborohydride under nitrogen. The mixture is stirred at room temperature for 3 hours. Evaporation of the mixture in vacuo gives an oil which solidifies on treatment with water. This solid is collected by filtration and is then stirred with a saturated solution of sodium bicarbonate, then is filtered, washed with water and dried in vacuo to give a white solid. Recrystallization from isopropyl alcohol gives 18.2 g of the desired product, mp 108-110° C.

1. temperaturecooled in a water bath
2. customEvaporation of the mixture in vacuo
3. customgives an oil which
4. filtrationThis solid is collected by filtration
5. stirringis then stirred with a saturated solution of sodium bicarbonate
6. filtrationis filtered
7. washwashed with water
8. customdried in vacuo
9. customto give a white solid
10. customRecrystallization from isopropyl alcohol