反应详情

249 g of 1-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]-pyridine-5-carboxylic acid, ethyl ester (1 mol) and 82 g of 3-aminocrotononitrile (1 mol) are heated together in 1.5 liters of butyl alcohol with stirring for 24 hours. The solvent is removed in vacuo and the residual 4-[2-(2-cyano-1-methylethylidene)hydrazino]-1-ethyl-1H-pyrazolo-[3,4-b]pyridine-5-carboxylic acid, ethyl ester is recrystallized from alcohol, yield 309 g (80%); m.p. 190°-191°.

1. customThe solvent is removed in vacuo
2. customthe residual 4-[2-(2-cyano-1-methylethylidene)hydrazino]-1-ethyl-1H-pyrazolo-[3,4-b]pyridine-5-carboxylic acid, ethyl ester is recrystallized from alcohol, yield 309 g (80%)