Azobisisobutyronitrile → HCID 23444990, compound

HRID 397870Notes

Reaction equation

HRID 397870 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([N:9]2[CH:13]=[CH:12][C:11]([CH3:14])=[N:10]2)[CH:5]=[CH:6][C:7]=1[Cl:8].BrN1C(=O)CCC1=O.N(C(C)(C)C#N)=NC(C)(C)C#N.[H-].[Na+].[CH3:37][C:38]1[NH:39][CH:40]=[CH:41][N:42]=1>C(Cl)(Cl)(Cl)Cl.CN(C=O)C.CCOC(C)=O>[ClH:1].[Cl:1][C:2]1[CH:3]=[C:4]([N:9]2[CH:13]=[CH:12][C:11]([CH2:14][N:39]3[CH:40]=[CH:41][N:42]=[C:38]3[CH3:37])=[N:10]2)[CH:5]=[CH:6][C:7]=1[Cl:8]

Participants

9

Reactant 5

HCID 6547AzobisisobutyronitrileHCID 127492-MethylimidazoleHCID 24758Sodium hydrideHCID 67184N-bromobutanimideHCID 234450371-(3,4-dichloro-phenyl)-3-methyl-1H-pyrazole

Product 1

HCID 23444990HCID 23444990, compoundYield 93.5%

Reagents, catalysts & solvents 3

HCID 5943Carbon TetrachlorideSolventHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of 1-(3,4-dichloro-phenyl)-3-methyl-1H-pyrazole (1.4 g, 6.1 mmol) in carbon tetrachloride was treated with N-bromosuccinimide (1.2 g, 6.8 mmol) and a catalytic amount of 2,2′azobis-(isobutyronitrile). The mixture was refluxed for 2 h, cooled, filtered and evaporated. The oily residue was dissolved in DMF (10 ml) and added to a solution of sodium hydride (0.32 g, 7.3 mmol, cf example 1) deprotonated 2-metylimidazole (0.60 g, 7.3 mmol) in DMF (10 ml). After stirring for 12 h at rt all volatiles were removed in vacuo and the residue obtained was dissolved in AcOEt. The organic phase was washed with H2O (3×), dried (Na2SO4) and concentrated. Purification by chromatography [silica, elution with gradient CH2Cl2 to 60% (CH2Cl2/MeOH/aq. NH4OH=90:10:1)] gave the free base of the title compound (0.98 g, 52%) as a light brown oil. After treatment with a solution of HCl in MeOH followed by addition of Et2O the title compound was isolated as a white crystalline material. Mp. 204-205° C. (MeOH/Et2O), MS: m/e=306 (M+).

Workup

  1. temperatureThe mixture was refluxed for 2 h
  2. temperaturecooled
  3. filtrationfiltered
  4. customevaporated
  5. dissolutionThe oily residue was dissolved in DMF (10 ml)
  6. customwere removed in vacuo
  7. customthe residue obtained
  8. washThe organic phase was washed with H2O (3×)
  9. dry with materialdried (Na2SO4)
  10. concentrationconcentrated
  11. customPurification
  12. washby chromatography [silica, elution with gradient CH2Cl2 to 60% (CH2Cl2/MeOH/aq. NH4OH=90:10:1)]

Sources & evidence

ORD record
ord-81490c0f8bea441799312ac3a41fb1d0
Source dataset
uspto-grants-2003_08
Patent number
US06610723B2

Reaction notes

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