反应详情

A suspension of N-cyano-4-(4-methoxypyridin-2-yl)-2-nitroaniline (200 mg) in ethanol (10 ml) was hydrogenated over Raney-nickel (500 mg) under a hydrogen atmosphere for 12 hours. The catalyst was filtered off, and the filtrate was evaporated under reduced pressure. The residue was purified by column chromatography (silica gel 20 g, dichloromethane:methanol:aqueous ammonia=100:10:1). The compound obtained was dissolved in ethyl acetate, and a solution of hydrogen chloride in 1,4-dioxane (4N, 1 ml) was added. The precipitate was collected by filtration and dried to give 2-amino-5-(4-methoxypyridin-2-yl)benzimidazole dihydrochloride (142 mg).

1. filtrationThe catalyst was filtered off
2. customthe filtrate was evaporated under reduced pressure
3. customThe residue was purified by column chromatography (silica gel 20 g, dichloromethane:methanol:aqueous ammonia=100:10:1)
4. customThe compound obtained
5. filtrationThe precipitate was collected by filtration
6. customdried