Sodium Hydroxide → N-Phenyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid

HRID 626282Notes

Reaction equation

HRID 626282 reaction equation
C([O:3][C:4]([C:6]1[C:7]([CH:21]([F:23])[F:22])=[N:8][N:9]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[C:10]=1[C:11]([F:14])([F:13])[F:12])=[O:5])C.[OH-].[Na+]>C(O)C>[C:15]1([N:9]2[C:10]([C:11]([F:14])([F:13])[F:12])=[C:6]([C:4]([OH:5])=[O:3])[C:7]([CH:21]([F:22])[F:23])=[N:8]2)[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=1

Participants

4

Reactant 2

HCID 14798Sodium HydroxideHCID 71770119N-Phenyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid ethyl ester

Product 1

HCID 71770253N-Phenyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acidYield 94%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

N-Phenyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid ethyl ester (3.0 g, 9.0 mmol) in ethanol (15 ml) was admixed gradually with an 8N aqueous sodium hydroxide solution (3.4 ml) and stirred at room temperature for 3 h. The solvent was removed by rotary evaporation; the residue was taken up in water (40 ml) and extracted with diethyl ether (20 ml). Acidification to pH 1 with 6M HCl was followed by extraction with ethyl acetate (3×30 ml). The combined organic phases were dried over sodium sulphate and filtered, and the solvent was removed by rotary evaporation. N-Phenyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid (2.58 g, 8.43 mmol, 94%) was isolated as a colourless solid.

Workup

  1. customThe solvent was removed by rotary evaporation
  2. extractionextracted with diethyl ether (20 ml)
  3. extractionAcidification to pH 1 with 6M HCl was followed by extraction with ethyl acetate (3×30 ml)
  4. dry with materialThe combined organic phases were dried over sodium sulphate
  5. filtrationfiltered
  6. customthe solvent was removed by rotary evaporation

Sources & evidence

ORD record
ord-16ff3f5bab2d46a39415dc3a5b032960
Source dataset
uspto-grants-2016_04
Patent number
US09309202B2

Reaction notes

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