反应详情

126 g. of 4-chloro-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid ethyl ester (0.5 mol.), 41.5 g. of 5-amino-pyrazole (0.5 mol.) and 50.6 g. of triethylamine (0.5 mol.) are heated at reflux temperature with stirring in 250 ml. of dimethylformamide for 16 hours. After cooling, about 300 ml. of water are added and the white precipitated product, 3-ethyl-3,11-dihydro-6H-pyrazolo[1,5-a]pyrazolo-[4',3':5,6]pyrido[4,3-d]pyrimidin-6-one is filtered off, yield 57.7 g. (45.4%); m.p. >300° (DMF).

1. temperatureat reflux temperature
2. temperatureAfter cooling
3. filtrationthe white precipitated product, 3-ethyl-3,11-dihydro-6H-pyrazolo[1,5-a]pyrazolo-[4',3':5,6]pyrido[4,3-d]pyrimidin-6-one is filtered off