64951-08-2

White to off-white solid

Step 2: Synthesis of imidazo[1,2-a]pyridine-2-carboxylic acid Sodium hydroxide (85 mg, 2.1 mmol) was added to a stirred solution of ethyl imidazo[1,2-a]pyridine-2-carboxylate (135 mg, 0.7 mmol) in ethanol/water (1:1, 5.0 mL). The reaction mixture was heated at 60°C for 3 hours. After completion of the reaction, the mixture was concentrated under reduced pressure. Cold water was added, followed by acidification with 10% aqueous hydrochloric acid to pH < 7. The precipitated solid was collected by filtration and dried to afford imidazo[1,2-a]pyridine-2-carboxylic acid (110 mg, 73% yield).

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