反应详情

A 3.42 g. portion of 6-(p-cyanophenyl)-3(2H)-pyridazinone in 25 ml. of phosphorus oxychloride is stirred and heated at reflux temperature for 3 hours. Most of the excess phosphorus oxychloride is removed under reduced pressure. Cracked ice-water is added to the concentrate which is stirred until the excess phosphorus oxychloride hydrolyzes. The solid is collected by filtration, dried and recrystallized from dimethylformamide-water, yielding 6-(p-cyanophenyl)-3-chloropyridazine, m.p. 236°-238° C.

1. temperatureheated
2. temperatureat reflux temperature for 3 hours
3. customMost of the excess phosphorus oxychloride is removed under reduced pressure
4. additionCracked ice-water is added to the
5. concentrationconcentrate which
6. filtrationThe solid is collected by filtration
7. customdried
8. customrecrystallized from dimethylformamide-water