Hydrogenation on palladium-containing granulated catalysts

摘要

Efficient hydrogenation of o-aminonitrobenzenes on palladium-containing granulated carbon catalysts in carboxylic acid solutions was accompanied by cyclization into aminobenzimidazoles.A simple hydrogenation reactor with a fixed gauze holding a reusable granulated catalyst was designed.Acylated and sulfonylated 4(7)-aminobenzimidazoles were obtained.In terms of electronic and geometrical parameters,they are close analogs of biologically active imidazo[l,5,4-e,f][l,5]benzodiazepines.