Phosphorus oxychloride → 5-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde

HRID 350864Notes

Reaction equation

HRID 350864 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4](O)[N:5]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[N:6]=1.P(Cl)(Cl)([Cl:16])=O.[C:19](=[O:22])([O-])O.[Na+]>CN(C)C=O>[Cl:16][C:4]1[N:5]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[N:6]=[C:2]([CH3:1])[C:3]=1[CH:19]=[O:22]

Participants

5

Reactant 3

HCID 24813Phosphorus oxychlorideHCID 516892Sodium BicarbonateHCID 178429253HCID 178429253, compound

Product 1

HCID 6130275-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

A solution containing 1.0 g of 5-methyl-2-phenyl-2H-pyrazol-3-ol (commercially available e.g. Aldrich M7,080-0) and 2.1 ml of phosphorus oxychloride in 10 ml of anhydrous N,N-dimethylformamide was stirred under nitrogen at 100° C. for 4 h. The mixture was poured into 70 ml of saturated sodium hydrogen carbonate and extracted three times with 60 ml of dichloromethane. The combined extracts were dried over magnesium sulphate, filtered and evaporated. The residue was purified by chromatography on silica gel using dichloromethane/methanol for the elution to give 177 mg of 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde as yellow needles.

Workup

  1. extractionextracted three times with 60 ml of dichloromethane
  2. dry with materialThe combined extracts were dried over magnesium sulphate
  3. filtrationfiltered
  4. customevaporated
  5. customThe residue was purified by chromatography on silica gel
  6. washfor the elution

Sources & evidence

ORD record
ord-3e82427924564026abfef2b217ff2299
Source dataset
uspto-grants-2007_02
Patent number
US07183296B2

Reaction notes

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