Synthesis of π-Extended Imidazo[1,2-]quinolines via Carboxylic Acid-Assisted Ru(II)-Catalyzed Dual C-H Activation and Alkyne Annulation.

Ru(II)-catalyzed, carboxylic acid-assisted oxidative annulation of -aryl azoles with alkynes via double C-H activation to produce highly functionalized π-extended imidazo[1,2-]quinolines is reported. The reaction features a broad substrate generality and tolerates various biologically relevant scaffolds. Interestingly, annulated products showed strong fluorescence properties and an AgIE effect and exhibited a selective fluorescent response toward the Cu ion. Further photocatalytic properties of the product are demonstrated in the photochemical coupling of azoles and arenes.