Document Type
Article
Language
eng
Publication Date
7-12-2017
Publisher
Wiley
Source Publication
Chemistry- A European Journal
Source ISSN
0947-6539
Abstract
The bimetallic catalyst [CoII2(L1)(bpy)2]ClO4 (1), in which L1 is an [NN′2O2] fused ligand, efficiently reduced H+ to H2 in CH3CN in the presence of 100 equiv of HOAc with a turnover number of 18 and a Faradaic efficiency of 94 % after 3 h of bulk electrolysis at −1.6 V (vs. Ag/AgCl). This observation allowed the proposal that this bimetallic cooperativity is associated with distance, angle, and orbital alignment of the two Co centers, as promoted by the unique Co−Namido−Co environment offered by L1. Experimental results revealed that the parent [CoIICoII] complex undergoes two successive metal‐based 1 e− reductions to generate the catalytically active species [CoICoI], and DFT calculations suggested that addition of a proton to one CoI triggers a cooperative 1 e− transfer by each of these CoI centers. This 2 e− transfer is an alternative route to generate a more reactive [CoII(CoII−H−)] hydride, thus avoiding the CoIII−H− required in monometallic species. This [CoII(CoII−H−)] species then accepts another H+ to release H2.
Recommended Citation
Kpogo, Kenneth K.; Mazumder, Shivnath; Wang, Denan; Schlegel, H. Bernhard; Fiedler, Adam T.; and Verani, Cláudio N., "Bimetallic Cooperativity in Proton Reduction with an Amido‐Bridged Cobalt Catalyst" (2017). Chemistry Faculty Research and Publications. 895.
https://epublications.marquette.edu/chem_fac/895
Comments
Accepted version. Chemistry- A European Journal, Vol. 23, No. 39 (July 2017): 9272-9279. DOI. © 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim. Used with permission.