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

HRID 12911Notes

Reaction equation

HRID 12911 reaction equation
C([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([CH:12]2[CH2:14][CH2:13]2)[C:10]=1[Cl:11])=[O:5])C.[Li+].[OH-]>CO.O>[Cl:11][C:10]1[N:9]([CH:12]2[CH2:13][CH2:14]2)[N:8]=[CH:7][C:6]=1[C:4]([OH:5])=[O:3]

Participants

5

Reactant 2

HCID 3939Lithium HydroxideHCID 67020969HCID 67020969, compound

Product 1

HCID 670209125-chloro-1-cyclopropyl-1H-pyrazole-4-carboxylic acidYield 94%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

To a solution of 5-Chloro-1-cyclopropyl-1H-pyrazole-4-carboxylic acid ethyl ester (296 mg, 1.38 mmol) in methanol (15 mL) and water (15 mL) was added LiOH (40 mg, 1.66 mmol). The reaction mixture was stirred at reflux overnight and then concentrated under reduced pressure to remove the methanol. The residue was diluted with water, acidified to pH=2 with concentrated HCl, and extracted with ethyl acetate. The organic extracts were evaporated in vacuo to give 5-chloro-1-cyclopropyl-1H-pyrazole-4-carboxylic acid (242 mg, 93%) which was used without further purification.

Workup

  1. temperatureat reflux overnight
  2. concentrationconcentrated under reduced pressure
  3. customto remove the methanol
  4. additionThe residue was diluted with water
  5. extractionextracted with ethyl acetate
  6. customThe organic extracts were evaporated in vacuo

Sources & evidence

ORD record
ord-7f6daa50c3f1427aafab853c24e7447e
Source dataset
uspto-grants-2010_06
Patent number
US07728029B2

Reaction notes

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