Synthesis of Substituted Pyrido[1,2‐a]benzimidazoles by Ruthenium‐Catalyzed C−H Bond Activation and Tandem Cyclization of 2‐Arylimidazo[1,2‐a]pyridines with Iodonium Ylides

Ruthenium-catalyzed C-H bond activation and tandem cyclization of 2-arylimidazo[1,2-a]pyridines with iodonium ylides proceed efficiently. For the first time, the easily available iodonium ylides and inexpensive ruthenium complex were employed to synthesize pyrido[1,2-a]benzimidazole derivatives in good yields under simple and easy-to-operate conditions. Several primary mechanism investigations and synthetic applications involving gram-scale preparation, derivatization reactions and the transformation of iodonium ylide generated in situ have also been conducted.