反应详情

A solution of 5-methoxybenzimidazole (500 mg, 3.374 mmol) in 48% hydrobromic acid (10 mL) was refluxed for 2 hours. The reaction was cooled to room temperature, the solvent removed by rotary evaporation under vacuum, and the residue azeotroped with toluene (50 mL) to provide the title compound as a tan solid (701 mg, 96%).

1. customthe solvent removed by rotary evaporation under vacuum
2. customthe residue azeotroped with toluene (50 mL)