Azobisisobutyronitrile → HCID 23444990, compound

HRID 433562Notes

Reaction equation

HRID 433562 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

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 (1.2g, 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, of 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-c10659a58fc8438f8490efc42e49ce8f
Source dataset
uspto-grants-2003_12
Patent number
US06667335B2

Reaction notes

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