Copper-catalyzed cascade reaction of indole and benzimidazole radicals to synthesize 3-haloindole-benzimidazole compounds

Abstract

A one-pot multi-component cascade reaction strategy between benzimidazole, indole, and N-halosuccinimides was developed through the combination of the Cu(II) catalyst and (bis(trifluoroacetoxy)iodo)benzene, mediated by initiating the formation of benzimidazole nitrogen-centered radicals. This strategy realizes the formation of nitrogen radicals centered on the aromatic nitrogen atoms in the ring. On this basis, the radical-level combined synthesis of substituted 3-haloindole-benzimidazole compounds was achieved. Furthermore, this study provides a reference direction for subsequent work utilizing nitrogen radicals.