反应详情

温度

170 °C

A mixture of 3.91 g of 6-ethoxycarbonyl-7-hydroxy-3-(4-phenylthiophenyl)-pyrazolo[1,5-a]pyrimidine obtained in Example 1 and 30 ml of 85% phosphoric acid was heated in a heating bath to 170° C., and stirred for 30 minutes, and the mixture gradually developed foams, and the foams were about to cease, the reaction solution turned to a dark red color. Stopping the heating bath, 200 ml of water was added, and after letting stand for 30 minutes while ice-cooling, the precipitate was filtered, washed in water and dried, and 2.55 g of the title compound was obtained.

1. additionwas added
2. customfor 30 minutes
3. temperaturecooling
4. filtrationthe precipitate was filtered
5. washwashed in water
6. customdried