Ici 109,081 → 4,5-dihydro-6-[p-(2-methoxypropoxycarbonylamino)-phenyl]-5-methyl-3(2H)-pyridazinone

HRID 1649096Notes

Reaction equation

HRID 1649096 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:9]([CH3:15])[CH2:10][C:11](=[O:14])[NH:12][N:13]=2)=[CH:4][CH:3]=1.Cl[C:17]([O:19][CH2:20][CH:21]([O:23][CH3:24])[CH3:22])=[O:18]>O1CCCC1>[CH3:24][O:23][CH:21]([CH3:22])[CH2:20][O:19][C:17]([NH:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:9]([CH3:15])[CH2:10][C:11](=[O:14])[NH:12][N:13]=2)=[CH:4][CH:3]=1)=[O:18]

Participants

4

Reactant 2

HCID 161928Ici 109,081HCID 204805592-Methoxypropyl chloroformate

Product 1

HCID 128050344,5-dihydro-6-[p-(2-methoxypropoxycarbonylamino)-phenyl]-5-methyl-3(2H)-pyridazinoneYield 73%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
60 °C

Procedure

5.0 g (24.6 millimoles) of 6-(p-aminophenyl)-4,5-dihydro-5-methyl-3(2H)-pyridazinone are dissolved in 150 ml of absolute tetrahydrofuran by heating to 60° C., with stirring. The solution is allowed to cool to room temperature, 5.6 g (36.7 millimoles) of 2-methoxypropyl chloroformate are added and the mixture is then stirred for 14 hours under reflux. It is concentrated, water is added and the product is filtered off and recrystallized from dimethylformamide/water, giving 5.7 g (73% of theory) of 4,5-dihydro-6-[p-(2-methoxypropoxycarbonylamino)-phenyl]-5-methyl-3(2H)-pyridazinone as colorless crystals of melting point 173°-175° C.

Workup

  1. temperatureto cool to room temperature
  2. stirringthe mixture is then stirred for 14 hours
  3. temperatureunder reflux
  4. concentrationIt is concentrated
  5. additionwater is added
  6. filtrationthe product is filtered off
  7. customrecrystallized from dimethylformamide/water

Sources & evidence

ORD record
ord-9a6490090ff7482288f383a6f2a2f0b0
Source dataset
uspto-grants-1983_11
Patent number
US04415571

Reaction notes

Loading…