Lithium Hydroxide → 1-cyclopropyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid

HRID 12821Notes

Reaction equation

HRID 12821 reaction equation
C([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([CH:15]2[CH2:17][CH2:16]2)[C:10]=1[C:11]([F:14])([F:13])[F:12])=[O:5])C.[Li+].[OH-]>CO.O>[CH:15]1([N:9]2[C:10]([C:11]([F:12])([F:13])[F:14])=[C:6]([C:4]([OH:5])=[O:3])[CH:7]=[N:8]2)[CH2:16][CH2:17]1

Participants

5

Reactant 2

HCID 3939Lithium HydroxideHCID 58972877Ethyl 1-cyclopropyl-5-(trifluoromethyl)-1H-pyrazole-4-carboxylate

Product 1

HCID 589728211-cyclopropyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acidYield 105.4%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

To a solution of 1-Cyclopropyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (140 mg, 0.56 mmol) in CH3OH (2 mL) and water (2 mL) was added LiOH (16 mg, 0.67 mmol). The reaction mixture was stirred at reflux overnight, and then the solution was concentrated under reduced pressure to remove the methanol. The residue was diluted with water and the solution was acidified to pH 2 with concentrated HCl. The resulting mixture was then extracted with ethyl acetate three times. The combined organic extracts were concentrated in vacuo to give 1-cyclopropyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid (130 mg, quantitative), which was used without further purification.

Workup

  1. temperatureat reflux overnight
  2. concentrationthe solution was concentrated under reduced pressure
  3. customto remove the methanol
  4. additionThe residue was diluted with water
  5. extractionThe resulting mixture was then extracted with ethyl acetate three times
  6. concentrationThe combined organic extracts were concentrated in vacuo

Sources & evidence

ORD record
ord-6d063a3a97f4470aa975d00c9cbdfba9
Source dataset
uspto-grants-2010_06
Patent number
US07728029B2

Reaction notes

Loading…