A recyclable Cu-catalyzed C–N coupling reaction in water and its application to synthesis of imidazo[1,2-a]quinoxaline

Polystyrene-supported pyrrole-2-carbohydrazide (PSP) was synthesized and combined with CuI to make up a recyclable heterogeneous catalytic system for Ullmann-type C–N coupling reaction in water. In which, a variety of functionalized aryl halides animated efficiently with anilines, benzylamine, aliphatic amines, and imidazole. its preliminary application resulted in a more practical synthesis of imidazo[1,2-a]quinoxaline.