Pyridine → HCID 178440332, compound

Participants

Reaction Steps

2-(2-ethoxy)-phenyl-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidine-7-one (50 g (0.16 mol)), phosphorus pentasulfide (17.8 g (0.08 mol)), pyridine (250 ml) were added into a 500 ml three-neck flask with a mechanical stirrer, stirred, heated and refluxed for 6 hours, TLC tracing was performed until the reactants were totally disappeared. The solvent pyridine was removed by distilling under reduced pressure, concentrated ammonia water ((25-28%) 75 ml) and ethanol 300 ml were added, heated and refluxed for 30 min. It was cooled, filtered, dried, and crude product (45 g) was obtained. The crude product was heated and solved into chloroform (150 ml), activated carbon (5 g) was added, stirring and reflux was performed for 30 min, it was filtered and the filtrate was washed with saturated brine and water consequently and dried with magnesium sulfate anhydrous, chloroform was removed by distilling, the obtained solid was re-crystallized with ethanol and dried, solid (38 g) was obtained with a yield of 72%.

Provenance & Evidence