4-Methoxybenzylamine → 2-methyl-1H-benzimidazole-5-carboxylic acid

Participants

Reaction Steps

To a dimethylformamide (20 ml) solution of 2-methylbenzimidazol-5-carboxylic acid (1.00 g) were added hydroxybenzotriazole (844 mg), 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (1.21 g) and 4-methoxyphenylmethylamine (1.33 g) at room temperature, and the reaction solution was stirred at room temperature for 18 hours. The reaction solution was concentrated under reduced pressure and the obtained residue was diluted with chloroform (20 ml). The organic layer was washed with saturated sodium hydrogen carbonate aqueous solution, water and saturated sodium chloride aqueous solution, and dried over anhydrous sodium sulfate. The residue obtained by solvent evaporation under reduced pressure was subjected to silica gel column chromatography and eluted with chloroform-methanol (30:1 (v/v)) to obtain (4-methoxyphenylmethyl)amide of 2-methyl-1H-benzimidazol-5-carboxylic acid (1.27 g, 99%).

Provenance & Evidence