2-[(Dimethylamino)methylidene]cyclohexane-1,3-dione → 1-(3,4-dichlorophenyl)-1,5,6,7-tetrahydro-4H-indazol-4-one

HRID 1180516Notes

Reaction equation

HRID 1180516 reaction equation
Cl.[Cl:2][C:3]1[CH:4]=[C:5]([NH:10][NH2:11])[CH:6]=[CH:7][C:8]=1[Cl:9].C([O-])(=O)C.[Na+].CN([CH:20]=[C:21]1[C:26](=[O:27])[CH2:25][CH2:24][CH2:23][C:22]1=O)C>CCCCO.C(O)(=O)C>[Cl:2][C:3]1[CH:4]=[C:5]([N:10]2[C:22]3[CH2:23][CH2:24][CH2:25][C:26](=[O:27])[C:21]=3[CH:20]=[N:11]2)[CH:6]=[CH:7][C:8]=1[Cl:9]

Participants

6

Reactant 3

HCID 3593532-[(Dimethylamino)methylidene]cyclohexane-1,3-dioneHCID 517045Sodium AcetateHCID 3084323(3,4-Dichlorophenyl)hydrazine monohydrochloride

Product 1

HCID 231129041-(3,4-dichlorophenyl)-1,5,6,7-tetrahydro-4H-indazol-4-oneYield 56%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 2631-ButanolSolvent2×

Procedure

A mixture of 1-(3,4-dichlorophenyl)hydrazine hydrochloride (6.78 g, 31.8 mmol) and anhydrous sodium acetate (2.60 g, 31.8 mmol) in n-BuOH (20 mL) is slowly added to a solution of 2-((dimethylamino)methylene)cyclohexane-1,3-dione (5.32 g, 31.8 mmol) in n-BuOH (100 mL) and acetic acid (5 mL). The resulting mixture is heated to reflux during 2 hours, effecting follow-up of the reaction by TLC. The solvent is evaporated at reduced pressure, the residue is diluted in AcOEt and washed with H2O. The solvent is next evaporated, and the crude is purified by silica-gel chromatography, to obtain 1-(3,4-dichlorophenyl)-1,5,6,7-tetrahydro-4H-indazol-4-one (5.0 g, 17.79 mmol, 56%, orange solid).

Workup

  1. temperatureThe resulting mixture is heated
  2. temperatureto reflux during 2 hours
  3. customeffecting follow-up of the reaction by TLC
  4. customThe solvent is evaporated at reduced pressure
  5. additionthe residue is diluted in AcOEt
  6. washwashed with H2O
  7. customthe crude is purified by silica-gel chromatography

Sources & evidence

ORD record
ord-c7061717fc1541cc856fd8bb0e9c9424
Source dataset
uspto-grants-2007_10
Patent number
US07282499B2

Reaction notes

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