反应详情

Dry ethanol is saturated with ammonia gas and placed in a sealed tube with 8.0 grams of 3,4,5-trichloropyridazine. The reaction mixture is heated at 120°-130° C. for five hours. The tube is opened and the reaction mixture concentrated under reduced pressure. The residue is dissolved in 20 ml of chloroform and the solution heated under reflux for 20 minutes. The solution is allowed to cool to ambient temperature for several hours in place. A solid precipitate is collected by filtration and repeatedly recrystallized from water to yield 2.8 grams of 4-amino-3,5-dichloropyridazine; m.p. 176°-178° C. The filtrate is concentrated under reduced pressure and the residue recrystallized from water to yield 2.0 grams of 4-amino-5,6-dichloropyridazine; m.p. 150°-151° C.

1. temperatureThe reaction mixture is heated at 120°-130° C. for five hours
2. concentrationthe reaction mixture concentrated under reduced pressure
3. dissolutionThe residue is dissolved in 20 ml of chloroform
4. temperaturethe solution heated
5. temperatureunder reflux for 20 minutes
6. filtrationA solid precipitate is collected by filtration
7. customrepeatedly recrystallized from water