Methanol → 4-chloro-1-(difluoromethyl)-1H-pyrazole-3-carboxylic acid

HRID 403265Notes

Reaction equation

HRID 403265 reaction equation
C[O:2][C:3]([C:5]1[C:9]([Cl:10])=[CH:8][N:7]([CH:11]([F:13])[F:12])[N:6]=1)=[O:4].[OH-].[Li+].O.CO>C1COCC1>[Cl:10][C:9]1[C:5]([C:3]([OH:4])=[O:2])=[N:6][N:7]([CH:11]([F:12])[F:13])[CH:8]=1

Participants

6

Reactant 4

HCID 887MethanolHCID 962WaterHCID 3939Lithium HydroxideHCID 574758834-Chloro-1-difluoromethyl-1H-pyrazole-3-carboxylic acid methyl ester

Product 1

HCID 574758564-chloro-1-(difluoromethyl)-1H-pyrazole-3-carboxylic acidYield 93.3%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of 4-chloro-1-difluoromethyl-1H-pyrazole-3-carboxylic acid methyl ester (540 mg, 2.6 mmole) in THF (18 ml) was treated at 23° C. with a solution of lithium hydroxide (135 mg, 5.6 mmole) in a 1:1-mixture of water and methanol (12 ml). After 1 hour the reaction was complete, and the solvents were evaporated at reduced pressure. The residue was partitioned between 2 M aqueous HCl and AcOEt, the organic layer was dried, evaporated, the residue was triturated with pentane and the solid was dried to give the title compound (477 mg) as a white solid. MS: m/z=195.0 [M−H]−.

Workup

  1. customthe solvents were evaporated at reduced pressure
  2. customThe residue was partitioned between 2 M aqueous HCl and AcOEt
  3. customthe organic layer was dried
  4. customevaporated
  5. customthe residue was triturated with pentane
  6. customthe solid was dried

Sources & evidence

ORD record
ord-f097348f55ff4ea5a6839bbacdf0f7b5
Source dataset
uspto-grants-2014_06
Patent number
US08748418B2

Reaction notes

Loading…