Ligand‐Centered Redox Driven Zn(II)‐Stabilized Azo‐Anion Radical Enabled Dehydrogenative Synthesis of Azines and Quinoxalines

ABSTRACT

Herein, we report a sustainable, one‐pot synthetic strategy for the synthesis of aldazines, ketazines, and quinoxalines in air using a cheap, nontoxic, and air‐stable Zn‐catalyst ( 1 ) bearing a redox‐active tridentate arylazo pincer, 2‐(4‐chlorophenyldiazenyl)‐1,10‐phenanthroline ( L ). Catalyst 1 exhibits promising catalytic activity for the synthesis of a broad spectrum of aldazines, ketazines, and quinoxalines in moderate to good isolated yields, using alcohols as inexpensive starting materials. Mechanistic investigations revealed an exclusively ligand‐centered redox‐driven catalytic dehydrogenation of alcohols, followed by subsequent coupling reactions, in which the Zn‐center serves merely as a template.