反应详情

A mixture of 20.0 g. of 6-(p-bromophenyl)-3(2H)-pyridazinone (prepared as described in Example 1) in 100 ml. of phosphorus oxychloride is heated at reflux temperature for 41/2 hours. The excess phosphorus oxychloride is removed under reduced pressure and the residue is stirred with water-cracked ice to decompose the remaining phosphorus oxychloride. The product is recovered by filtration and recrystallized from dilute dimethylformamide yielding tan crystals, m.p. 201°-203° C.

1. additionA mixture of 20.0 g
2. temperatureat reflux temperature for 41/2 hours
3. customThe excess phosphorus oxychloride is removed under reduced pressure
4. filtrationThe product is recovered by filtration
5. customrecrystallized from dilute dimethylformamide yielding tan crystals, m.p. 201°-203° C.