title: Photocatalytic Conversion of CO2to CO using Rhenium Bipyridine Platforms Containing Ancillary Phenyl or BODIPY Moieties.
abstract: Harnessing of solar energy to drive the reduction of carbon dioxide to fuels requires the development of efficient catalysts that absorb sunlight. In this work, we detail the synthesis, electrochemistry and photophysical properties of a set of homologousfac-ReI(CO)3complexes containing either an ancillary phenyl (8) or BODIPY (12) substituent. These studies demonstrate that both the electronic properties of the rhenium center and BODIPY chromophore are maintained for these complexes. Photolysis studies demonstrate that both assemblies8and12are competent catalysts for the photochemical reduction of CO2to CO in DMF using triethanolamine (TEOA) as a sacrificial reductant. Both compounds8and12display TOFs for photocatalytic CO production upon irradiation with light (λex≥ 400 nm) of ~5 hr-1with TON values of approximately 20. Although structural and photophysical measurements demonstrate that electronic coupling between the BODIPY andfac-ReI(CO)3units is limited for complex12, this work clearly shows that the photoactive BODIPY moiety is tolerated during catalysis and does not interfere with the observed photochemistry. When taken together, these results provide a clear roadmap for the development of advanced rhenium bipyridine complexes bearing ancillary BODIPY groups for the efficient photocatalytic reduction of CO2using visible light.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716.
authors.forename: Gabriel A
authors.initials: GA
authors.lastname: Andrade
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Pistner
authors.forename: Glenn P A
authors.initials: GP
authors.lastname: Yap
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Lutterman
authors.forename: Joel
authors.initials: J
authors.lastname: Rosenthal
keywords: BODIPY; carbon dioxide; catalysis; electrochemistry; photochemistry; rhenium bipyridine derivatives