[NH2:1][C:2]1[N:6]([CH3:7])[N:5]=[C:4]([C:8]([F:11])([F:10])[F:9])[C:3]=1[C:12]([O:14]CC)=[O:13].[OH-].[Na+]>O>[NH2:1][C:2]1[N:6]([CH3:7])[N:5]=[C:4]([C:8]([F:11])([F:10])[F:9])[C:3]=1[C:12]([OH:14])=[O:13]To 10 ml of water, 2.37 g (10 mmol) of ethyl 5-amino-1-methyl-3-trifluoromethylpyrazole-4-carboxylate and 0.44 g (11 mmol) of sodium hydroxide were added and stirred at 60° C. for 10 hours. After cooling to room temperature, the reaction mixture was washed with toluene. The resulting aqueous solution was made pH 1 by adding concentrated hydrochloric acid. Precipitate was filtered and dried to obtain 1.78 g of desired 5-amino-1-methyl-3-trifluoromethylpyrazole-4-carboxylic acid as white solid. The yield was 85% Following results were obtained by NMR analysis.
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