Ammonia → 1-Methyl-1,5-dihydropyrazolo(3,4-d)pyrimidin-4-one

Participants

Reaction Steps

57.2 g. of 5 -[(ethoxymethylene)amino]-1-methyl-1H- pyrazole-4-carboxylic acid, ethyl ester are dissolved in 200 ml. of ethanol, 4.4 g. of ammonia are added and the reaction mixture is autoclaved at 60° for 40 hours. After cooling, the mixture is filtered and the residual 1-methyl-1,5-dihydro-4H-pyrazolo- [3,4-d]pyrimidin-4-one is crystallized from dimethylformamide, m.p. 289°-290° (yield 31 g. - 80.7%).

Provenance & Evidence