Sodium Hydroxide → N-tert-Butyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid
Reaction equation
C([O:3][C:4]([C:6]1[C:7]([CH:19]([F:21])[F:20])=[N:8][N:9]([C:15]([CH3:18])([CH3:17])[CH3:16])[C:10]=1[C:11]([F:14])([F:13])[F:12])=[O:5])C.[OH-].[Na+]>C(O)C>[C:15]([N:9]1[C:10]([C:11]([F:14])([F:13])[F:12])=[C:6]([C:4]([OH:5])=[O:3])[C:7]([CH:19]([F:21])[F:20])=[N:8]1)([CH3:18])([CH3:16])[CH3:17]Participants
4
Procedure
N-tert-Butyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid ethyl ester (2.48 g, 7.9 mmol) in ethanol (15 ml) was admixed gradually with an 8N aqueous sodium hydroxide solution (3.0 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-tert-Butyl-3-difluoromethyl-5-trifluoromethyl-4-pyrazolecarboxylic acid (2.15 g, 7.52 mmol, 94%) was isolated as a yellow solid.
Workup
- customThe solvent was removed by rotary evaporation
- extractionextracted with diethyl ether (20 ml)
- extractionAcidification to pH 1 with 6M HCl was followed by extraction with ethyl acetate (3×30 ml)
- dry with materialThe combined organic phases were dried over sodium sulphate
- filtrationfiltered
- customthe solvent was removed by rotary evaporation
Sources & evidence
- ORD record
- ord-2421d499ac5f4b5b82fa53c95210e618
- Source dataset
- uspto-grants-2016_04
- Patent number
- US09309202B2
Reaction notes
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