反应详情

A 3.37 g amount of 4,5-dihydro-7-[3-(trifluoromethyl)phenyl]pyrazolo[1,5-a]pyrimidine-3-carboxylic acid, ethyl ester (prepared as described in Ex. 22) was added to a solution of 1.4 g of potassium hydroxide in 100 ml of ethanol. This mixture was heated at reflux for 5 hours, cooled to room temperature and evaporated to dryness in vacuo. The residue was dissolved in water and the solution was neutralized to pH 7.0 with concentrated hydrochloric acid. The white precipitate formed was collected by filtration, washed with water and dried in vacuo to give 2.5 g of the desired product as a whtie solid, mp 175°-177° C.

1. temperatureThis mixture was heated
2. temperatureat reflux for 5 hours
3. customevaporated to dryness in vacuo
4. dissolutionThe residue was dissolved in water
5. customThe white precipitate formed
6. filtrationwas collected by filtration
7. washwashed with water
8. customdried in vacuo