C([O:3][C:4]([C:6]1[C:10]([C:11]([F:14])([F:13])[F:12])=[CH:9][N:8]([CH3:15])[N:7]=1)=[O:5])C.[OH-].[Na+]>CO>[CH3:15][N:8]1[CH:9]=[C:10]([C:11]([F:13])([F:14])[F:12])[C:6]([C:4]([OH:5])=[O:3])=[N:7]11-Methyl-4-trifluoromethyl-1H-pyrazole-3-carboxylic acid ethyl ester (20 g, 90 mmol) was dissolved in methanol (100 ml). Sodium hydroxide in methanol (1M) (95 ml, 95 mmol) was added dropwise. The mixture was stirred at room temperature for 2 hours, stored at room temperature for 16 hours and concentrated. The residue was dissolved in aqueous hydrochloric acid (2M) (55 ml) and isopropyl acetate (300 ml). The two phases were separated and the aqueous phase was extracted with more isopropyl acetate (100 ml). The combined organic extracts were dried over magnesium sulfate and concentrated. This gave the product as a white solid (17.5 g, 100% yield). M.p. 174-175° C.
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