1865-09-4

The Journal of Organic Chemistry, 39, p. 1519, 1974 DOI: 10.1021/jo00924a014

1H-benzimidazole-2-carboxylic acid (500 mg, 3.08 mmol) was suspended in anhydrous ethanol (5 mL) and thionyl chloride (1.12 mL, 15.4 mmol) was slowly added dropwise, followed by heating the reaction mixture to reflux and stirring overnight. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure to afford the crude product ethyl 1H-benzo[d]imidazole-2-carboxylate (644 mg, 99% yield).

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