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

HRID 12921Notes

Reaction equation

HRID 12921 reaction equation
C([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([CH:12]2[CH2:15][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][CH2:15]2)[N:8]=[CH:7][C:6]=1[C:4]([OH:5])=[O:3]

Participants

5

Reactant 2

HCID 3939Lithium HydroxideHCID 58972820HCID 58972820, compound

Product 1

HCID 589728585-chloro-1-cyclobutyl-1H-pyrazole-4-carboxylic acidYield 94%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

To a solution of 5-chloro-1-cyclobutyl-1H-pyrazole-4-carboxylic acid ethyl ester (182 mg, 0.79 mmol) in methanol (8 mL) and water (8 mL) was added LiOH (23 mg, 0.96 mmol). The reaction mixture was stirred at reflux for 4 hours 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 layer was evaporated in vacuo to give 5-chloro-1-cyclobutyl-1H-pyrazole-4-carboxylic acid (148 mg, 94%) which was used without further purification.

Workup

  1. temperatureat reflux for 4 hours
  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 layer was evaporated in vacuo

Sources & evidence

ORD record
ord-dd3268c8f97946cc86e36fdf228ddcd2
Source dataset
uspto-grants-2010_06
Patent number
US07728029B2

Reaction notes

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