Sodium Hydroxide → 1-Phenyl-3-(trifluoromethyl)-1H-pyrazole-4-carboxylic acid

HRID 1641795Notes

Reaction equation

HRID 1641795 reaction equation
C([O:3][C:4]([C:6]1[C:7]([C:17]([F:20])([F:19])[F:18])=[N:8][N:9]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH:10]=1)=[O:5])C.[OH-].[Na+]>CO>[C:11]1([N:9]2[CH:10]=[C:6]([C:4]([OH:5])=[O:3])[C:7]([C:17]([F:19])([F:20])[F:18])=[N:8]2)[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=1

Participants

4

Reactant 2

HCID 14798Sodium HydroxideHCID 11448972Ethyl 1-phenyl-3-(trifluoromethyl)-1H-pyrazole-4-carboxylate

Product 1

HCID 149682451-Phenyl-3-(trifluoromethyl)-1H-pyrazole-4-carboxylic acidYield 89%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A mixture of 1-phenyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (1.25 g, 4.4 mmol) and 1N aqueous sodium hydroxide solution (17.3 mL) in methanol (20 mL) was stirred at room temperature overnight. The reaction mixture was concentrated and acidified to pH ˜1 with 1N aqueous hydrochloric acid. The slurry was extracted with methylene chloride and the combined organic layers were washed with saturated sodium chloride and dried over sodium sulfate. Filtration and concentration gave 1-phenyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid (1 g, 89% yield) as an off-white solid, which was directly used in the next step without further purification. LCMS calcd for C11H7F3N2O2 (m/e) 256, obsd 255 (M−H).

Workup

  1. concentrationThe reaction mixture was concentrated
  2. extractionThe slurry was extracted with methylene chloride
  3. washthe combined organic layers were washed with saturated sodium chloride
  4. dry with materialdried over sodium sulfate
  5. filtrationFiltration and concentration

Sources & evidence

ORD record
ord-5344087abc3c4f02a0bdf8657de3b644
Source dataset
uspto-grants-2012_02
Patent number
US08115011B2

Reaction notes

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