Ni-Catalyzed Dual C-H Annulation of Benzimidazoles with Alkynes for Synthesis of π-Extended Heteroarenes

Transition metal catalyzed dual C-H activation and annulation with alkynes was an attractive protocol to construct polycyclic pi-extended structures. However, most of them were dominated by noble metal catalysts. Disclosed herein was the study of base-metal Ni-catalysis for dual C-H annulation of N-aromatic imidazole, which produced a range of desired polycyclic aza-quinolines in 48-95% yields. The use of bifunctional phosphine oxide ligand proved to be critical for success.

Automated summary

The study successfully demonstrated the dual C-H annulation of N-aromatic imidazole using a base-metal Ni catalyst, yielding a range of desired polycyclic aza-quinolines in 48-95% yields. The use of bifunctional phosphine oxide ligand was crucial for the success of the reaction.