反应详情

A mixture of 4,7-dihydro-6-ethoxycarbonyl-2-(4-fluorophenyl)-3-(pyridin-4-yl)-7-oxopyrazolo[1,5-a]pyrimidine (946 mg) in sulfuric acid (40% in water, 5 ml) was refluxed for 2 hours. After cooling, the pH of the reaction mixture was adjusted to 5 with an aqueous saturated sodium bicarbonate solution. The crude crystalline was obtained and washed with hot ethanol to give 4,7-dihydro-6-carboxy-2-(4-fluorophenyl)-3-(pyridin-4-yl)-7-oxopyrazolo[1,5-a]pyrimidine (275 mg).

1. temperaturewas refluxed for 2 hours
2. temperatureAfter cooling
3. customThe crude crystalline was obtained
4. washwashed with hot ethanol