Sodium Hydroxide → 1-tert-butyl-5-(5-methyl-isoxazol-3-yl)-1H-pyrazole-4-carboxylic acid
Reaction equation
C[O:2][C:3]([C:5]1[CH:6]=[N:7][N:8]([C:16]([CH3:19])([CH3:18])[CH3:17])[C:9]=1[C:10]1[CH:14]=[C:13]([CH3:15])[O:12][N:11]=1)=[O:4].[OH-].[Na+]>CO>[C:16]([N:8]1[C:9]([C:10]2[CH:14]=[C:13]([CH3:15])[O:12][N:11]=2)=[C:5]([C:3]([OH:4])=[O:2])[CH:6]=[N:7]1)([CH3:19])([CH3:17])[CH3:18]Participants
Conditions
- Temperature
- 25 °C
Procedure
A solution of 1-tert-butyl-5-(5-methyl-isoxazol-3-yl)-1H-pyrazole-4-carboxylic acid methyl ester (7.37 g, 26.59 mmol) in methanol (17.7 mL, 1.5M) cooled to 0° C. was treated dropwise with a 4N aqueous sodium hydroxide solution (13.3 mL, 53.15 mmol). The reaction was allowed to slowly warm to 25° C. The reaction was stirred at 25° C. over-night. At this time, the reaction was concentrated in vacuo to remove methanol. The residue was diluted with water (150 mL) and was then extracted with dichloromethane (3×150 mL). These organics were discarded. The aqueous layer was then acidified to pH=1 with a 2N aqueous hydrochloric acid solution. This solution was extracted with a 90/10 dichloromethane/methanol solution (3×150 mL). The combined organics were dried over sodium sulfate, filtered and concentrated in vacuo to afford 1-tert-butyl-5-(5-methyl-isoxazol-3-yl)-1H-pyrazole-4-carboxylic acid (5.42 g, 82%) as a brown solid. The material was used without further purification.
Workup
- concentrationAt this time, the reaction was concentrated in vacuo
- customto remove methanol
- additionThe residue was diluted with water (150 mL)
- extractionwas then extracted with dichloromethane (3×150 mL)
- extractionThis solution was extracted with a 90/10 dichloromethane/methanol solution (3×150 mL)
- dry with materialThe combined organics were dried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated in vacuo
Sources & evidence
- ORD record
- ord-69aef1aa64f64871bf7a888c6526a5c9
- Source dataset
- uspto-grants-2010_06
- Patent number
- US07728029B2
Reaction notes
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