Palladium-catalyzed regioselective synthesis of 2(2′-biphenyl)benzimidazoles through C-H activation

An efficient palladium-catalyzed strategy through C-H bond activation for the synthesis of 2(2-biphenyl)-benzimidazoles is reported herein. The regioselective C-C bond formation proceeds in a sealed tube via oxidative C-H activation of ortho-directed 2-aryl-benzimidazole to couple with various iodobenzene analogs in high yields. This arylation exhibited high regioselectivity which is able to increase molecular diversity in difficult functionalized positions of parent molecules. This strategy provides a convenient and simple synthesis of biphenyl heterocyclic compounds with high regioselectivity.