59020-44-9

GENERAL METHOD: To a methanolic solution of ethyl 4-phenylthiazole-2-carboxylate (1 equiv.) was slowly added 2N sodium hydroxide solution at room temperature. The reaction mixture was stirred continuously for 4 h. After completion of the reaction, the methanol solvent was removed by rotary evaporator. The residue was adjusted to pH 5-6 with 1N hydrochloric acid solution, at which point the target product 4-phenylthiazole-2-carboxylic acid precipitated as a white solid. The precipitate was collected by filtration and washed with appropriate amount of deionized water and finally dried in a vacuum drying oven to give pure 4-phenylthiazole-2-carboxylic acid (1a-i).

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