反应详情

To a solution of 3.6 g of 5-ethylthio-7-phenyl-1,2,4-triazolo[4,3-c]pyrimidine in 100 ml of hot ethanol was added 1.4 g of concentrated sulfuric acid. The mixture was cooled, an equal volume of diethyl ether was added and the precipitate was collected by filtration. The precipitate was recrystallized from a mixture of methanol and diethyl ether to provide 5-ethylthio-7-phenyl-1,2,4-triazolo[4,3-c]pyrimidine dihydrogen sulfate hydrate, m.p. 213°-214° C.

1. temperatureThe mixture was cooled
2. filtrationthe precipitate was collected by filtration
3. customThe precipitate was recrystallized from a mixture of methanol and diethyl ether