反应详情

Heat Then g. of 3-(5-nitro-2-furyl)-1H-pyrazole-4-carboxaldehydeoxime together with 3.4 g of phosphorus oxychloride in 20 ml of 1,2-dichloroethane for 1 hour under reflux. To the resulting product add ice together with 50 ml of water. The adjust the pH to from 3 to 4 with sodium hydrogen carbonate and remove the formed crystals by vacuum filtration. Wash the crystals with water to obtain a 96% yield of 3-(5-nitro-2-furyl)-1H-pyrazole-4-carbonitrile [m.p. 237.5° to 239° C (from ethanol)].

1. temperatureHeat
2. customremove the formed crystals
3. filtrationby vacuum filtration
4. washWash the crystals with water