[OH-].[K+].C([O:5][C:6]([C:8]1[N:9]=[C:10]2[CH:15]=[CH:14][CH:13]=[C:12]([CH3:16])[N:11]2[C:17]=1[C:18]1[CH:23]=[CH:22][CH:21]=[C:20]([C:24]([F:27])([F:26])[F:25])[CH:19]=1)=[O:7])C>CO.O>[CH3:16][C:12]1[N:11]2[C:17]([C:18]3[CH:23]=[CH:22][CH:21]=[C:20]([C:24]([F:27])([F:25])[F:26])[CH:19]=3)=[C:8]([C:6]([OH:7])=[O:5])[N:9]=[C:10]2[CH:15]=[CH:14][CH:13]=1Potassium hydroxide (0.2 g, 0.003 mol) was added to a suspension of 5-Methyl-3-(3-trifluoromethyl-phenyl)-imidazo[1,2-a]pyridine-2-carboxylic acid ethyl ester (compound p, 0.35 g, 0.0010 mol) in methanol (0.4 mL) and water (4.7 mL). Stirred at 80° C. for 1 hour. The methanol was removed and 6N HCl added to the residue until pH approx. 5. The white solid that formed was filtered to give 290 mg of 5-methyl-3-(3-(trifluoromethyl)phenyl) imidazo[1,2-a]pyridine-2-carboxylic acid as a white solid. Rf 0.20, 100% ethyl acetate; MS m/z 319 (M−H).
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