反应详情

A mechanically stirred mixture of 3-aminopyrazole (9.38 g, 0.11 mM, 1.0 equiv), 1,3-dimethyluracil (14.7 g, 0.11 mM, 1.0 equiv) and 21% sodium ethoxide in ethanol (170 mL, 5.0 equiv) was heated to reflux. Within minutes, a heavy precipitate formed. After refluxing for 1 hour, 1,3-dimethyluracil could no longer be detected by thin layer chromatography (tlc) (92:8 dichloromethane (dichloromethane):MeOH). The reaction mixture was cooled, filtered, washed with cold ethanol and vacuum dried to give 13.47 g (95%) of sodium pyrazolo[1,5-a]pyrimidin-5-olate. LCMS (ESI) m+H=136.0; 1H NMR (400 MHz, DMSO-d6) δ: 8.0 (d, 1H), 7.43 (d, 1H), 5.65 (d, 1H), 5.37 (d, 1H).

1. temperaturewas heated to reflux
2. waitWithin minutes
3. customa heavy precipitate formed
4. temperatureAfter refluxing for 1 hour
5. temperatureThe reaction mixture was cooled
6. filtrationfiltered
7. washwashed with cold ethanol and vacuum
8. customdried