Zn(II)-Stabilized Azo-Anion Radical-Catalyzed Dehydrogenative Synthesis of Olefins

Herein, we describe a Zn-catalyzed atom-economical, inexpensive, and sustainable method for preparing a broad spectrum of substituted olefins utilizing alcohols as the main precursor. Using a Zn(II) complex [ZnLCl₂] (<b>1</b>) of the redox-noninnocent ligand 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (<b>L</b>), various (<i>E</i>)-olefins were prepared in good yields by coupling alcohols with sulfones and aryl cyanides under an inert atmosphere. Under an aerial atmosphere, vinyl nitriles were isolated in up to 82% yield reacting alcohols with benzyl cyanides in the presence of <b>1</b>. Control experiments and mechanistic investigation indicate the active involvement of the aryl-azo ligand as an electron and hydrogen reservoir, permitting <b>1</b> to perform as a promising catalyst.