反应详情

7-methoxy-2-phenyl-1H-benzoimidazole-4-carboxylic acid methyl ester (4.5 g, 15.94 mmol) obtained in step 3 was dissolved in 100 ml of toluene, aluminum chloride (9.56 g, 71.73 mmol) was added thereto and refluxed for 8 hours. The resulting solution was cooled to room temperature, the reaction was stopped by adding 3 N HCl thereto and stirred for 30 min. The precipitate formed was filtered, washed with benzene and dried to obtain the title compound (3.5 g, 13.77 mmol) in a yield of 86%.

1. temperaturerefluxed for 8 hours
2. customThe precipitate formed
3. filtrationwas filtered
4. washwashed with benzene
5. customdried