Regioselective Monoarylation of 2-Phenylbenzimidazole via Ruthenium-Catalyzed­ C–H Bond Functionalization

Abstract

The highly regioselective monoarylation of 1-methyl-2-phenyl-1H-benzimidazole has been demonstrated. The reaction of 1-methyl-2-phenyl-1H-benzimidazole with 4-iodoanisole provided 2-(4′-methoxybiphenyl-2-yl)-1-methyl-1H-benzimidazole as the sole product in 96% isolated yield in the presence of [RuCl₂(p-cymene)]₂ and triphenylphosphine as precatalysts. A series of novel 2-(biphenyl-2-yl)benzimidazoles have been synthesized in good to excellent yields.

Key words

C–H bond activation - benzimidazole - arylation - ruthenium catalyst - directing group

• References


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