Acetic Acid → 2-dimethylamino-6,8-dihydrothieno[3,4-d]-1,2,4-triazolo-[1,5-a]pyrimidine-5(9H)-one

Participants

Reaction Steps

To 19.1 g (0.15 mole) of 5-amino-3-dimethylamino-1H-1,2,4-triazole dissolved in 15 ml of acetic acid 24.3 g (0.15 moles) of methyl 4-oxo-tetrahydrothiophene-3-carboxylate are added and the reaction mixture is boiled for 15 minutes. The product precipitated from the reaction mixture is filtered off from the hot solution, then washed with i-propanol and recrystallized from dimethylformamide. Thus 26.1 g (73.3%) of 2-dimethylamino-6,8-dihydrothieno[3,4-d]-1,2,4-triazolo-[1,5-a]pyrimidine-5(9H)-one are obtained. Melting point: 355°-360° C.

Provenance & Evidence