Palladium‐Catalyzed Ligand‐Free C‐N Coupling Reactions: Selective Diheteroarylation of Amines with 2‐Halobenzimidazoles

2‐Aminobenzimidazoles are widely present in a number of bioactive molecules. Generally, the preparation of these molecules could be realized by the mono‐substitution of 2‐halobenzimidazoles with amines. However, rare examples were reported for the di‐substituted products and the selectivity of mono‐ vs. di‐substitution was relatively low. Considering the potential values of the di‐substituted products, we accomplished the first selective diheteroarylation of amines with 2‐halobenzimidazoles. Notably, this Pd‐catalyzed transformation was realized under ligand‐free conditions. Accordingly, numerous target products were efficiently produced from various aromatic or aliphatic amines and 2‐halobenzimidazoles. It was worth noting that two representative products were further confirmed by X‐ray crystallography. More significantly, this catalytic process could be applied to the synthesis and discovery of new bioactive compounds, which demonstrated the synthetic usefulness of this newly developed approach. The first selective diheteroarylation of amines with 2‐halobenzimidazoles was accomplished via a Pd‐catalyzed ligand‐free process. Accordingly, numerous target products were efficiently produced from various aromatic or aliphatic amines and 2‐halobenzimidazoles. More significantly, this catalytic process could be applied to the synthesis and discovery of new bioactive compounds, which demonstrated the synthetic usefulness of this newly developed approach.