Rhenium Complexes of Pyridyl-Mesoionic Carbenes: Photochemical Properties and Electrocatalytic CO2 Reduction

0524277 - ÚFCH JH 2021 RIV US eng J - Journal Article
Suntrup, L. - Stein, F. - Klein, J. - Wilting, A. - Parlane, F. G. L. - Brown, Ch. M. - Fiedler, Jan - Berlinguette, C. P. - Siewert, I. - Sarkar, B.
Rhenium Complexes of Pyridyl-Mesoionic Carbenes: Photochemical Properties and Electrocatalytic CO2 Reduction.
Inorganic Chemistry. Roč. 59, č. 7 (2020), s. 4215-4227. ISSN 0020-1669. E-ISSN 1520-510X
R&D Projects: GA ČR(CZ) GA18-09848S
Institutional support: RVO:61388955
Keywords : carbon-dioxide * structural-characterization * photophysical properties * ligands synthesis * metal-complexes * approximation * triazoles * catalysts * water * hydrogenation
OECD category: Physical chemistry
Impact factor: 5.165, year: 2020
Method of publishing: Limited access

Mesoionic carbenes have found wide use as components of homogeneous catalysts. Recent discoveries have, however, shown that metal complexes of such ligands also have huge potential in photochemical research and in the activation of small molecules. We present here three Re-I complexes with mesoionic pyridyl-carbene ligands. The complexes display reduction steps which were investigated via UV-vis-NIR-IR spectro-electrochemistry, and these results point toward an EC mechanism. The Re-I compounds emit in the visible range in solution at room temperature with excited state lifetimes that are dependent on the substituents of the mesoionic carbenes. These complexes are also potent electrocatalysts for the selective reduction of CO2 to CO. Whereas the substituents on the carbenes have no influence on the reduction potentials, the electrocatalytic efficiency is strongly dependent on the substituents. This fact is likely a result of catalyst instability. The results presented here thus introduce mesoionic carbenes as new potent ligands for the generation of emissive Re-I complexes and for electrocatalytic CO2 reduction.
Permanent Link: http://hdl.handle.net/11104/0308650