Ammonium Acetate → 2-isoquinolin-3-yl-1H-benzoimidazole-4-carboxylic acid

Participants

Reaction Steps

To a solution of the above crude product 2-amino-3-[(isoquinoline-3-carbonyl)-amino]-benzoic acid methyl ester in AcOH (25 mL) was added AcONH4 (16 g). The reaction mixture was refluxed for 3 h. After removal of AcOH under vacuum, the reaction mixture was washed with water (150 mL) The crude solid product 2-isoquinolin-3-yl-1H-benzoimidazole-4-carboxylic acid methyl ester was collected after filtration. LCMS: 304 (M+1)+. This product was hydrolyzed according to the general procedure C to provide 2-isoquinolin-3-yl-1H-benzoimidazole-4-carboxylic acid (1.6 g, 55% yield over three steps). LCMS: 290 (M+1)+.

Provenance & Evidence