反应详情

50 gms. of 1-(1,3-dimethyl-4-nitro-1H-pyrazol-5-yl)-1H-pyrazole-4,5-dicarboxylic acid, diethyl ester, are hydrogenated with 0.2 gms. of palladium-carbon in 100 ml. of glacial acetic acid at 60° until the uptake of hydrogen stops. On cooling, the product, 5-hydroxy-1,3-dimethyl-1H-dipyrazolo[1,5-a:4',3'-e]pyrazine-6-carboxylic acid, ethyl ester, crystallizes in the form of white filamentous needles. On evaporating the solvent, the product is recrystallized from dimethylformamide, yield 22 gms. of white needles, m.p. 246°-247°.

1. customat 60°
2. temperatureOn cooling
3. customthe product, 5-hydroxy-1,3-dimethyl-1H-dipyrazolo[1,5-a:4',3'-e]pyrazine-6-carboxylic acid, ethyl ester, crystallizes in the form of white filamentous needles
4. customOn evaporating the solvent
5. customthe product is recrystallized from dimethylformamide, yield 22 gms