Ammonia → 3,5-Dichloro-1,4-dihydropyridazin-4-imine

HRID 568308Notes

Reaction equation

HRID 568308 reaction equation
[NH3:1].[Cl:2][C:3]1[N:4]=[N:5][CH:6]=[C:7]([Cl:10])[C:8]=1Cl>C(O)C>[NH2:1][C:8]1[C:7]([Cl:10])=[CH:6][N:5]=[N:4][C:3]=1[Cl:2]

Participants

4

Reactant 2

HCID 222AmmoniaHCID 701113,4,5-Trichloropyridazine

Product 1

HCID 64032013,5-Dichloro-1,4-dihydropyridazin-4-imine

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

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.

Workup

  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

Sources & evidence

ORD record
ord-91bb49642bac4ae988c8ba2ee8d5982e
Source dataset
uspto-grants-1988_03
Patent number
US04728355

Reaction notes

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