Mediated Inner‐Sphere Electron Transfer Induces Homogeneous Reduction of CO <sub>2</sub> via Through‐Space Electronic Conjugation**
Shelby L. Hooe, Juan J. Moreno, Amelia G. Reid, Emma N. Cook, Charles W. Machan
Abstract
Abstract The electrocatalytic reduction of CO 2 is an appealing method for converting renewable energy sources into value‐added chemical feedstocks. We report a co‐electrocatalytic system for the reduction of CO 2 to CO comprised of a molecular Cr complex and dibenzothiophene‐5,5‐dioxide (DBTD) as a redox mediator, which achieves high activity (TOF=1.51–2.84×10 5 s −1 ) and quantitative selectivity. Under aprotic or protic conditions, DBTD produces a co‐electrocatalytic response with 1 by coordinating trans to the site of CO 2 binding and mediating electron transfer from the electrode with quantitative efficiency for CO. This assembly is reliant on through‐space electronic conjugation between the π frameworks of DBTD and the bpy fragment of the catalyst ligand, with contributions from dispersive interactions and weak sulfone coordination.