title: Supramolecular assembly promotes the electrocatalytic reduction of carbon dioxide by Re(I) bipyridine catalysts at a lower overpotential.
abstract: The addition of methyl acetamidomethyl groups at the 4,4'-positions of a 2,2'-bipyridyl ligand is found to enhance the rate of a bimolecular reduction mechanism of CO2 by Re(I) fac-tricarbonyl chloride complexes. Electrochemical studies, spectroelectrochemical measurements, and molecular dynamics simulations indicate that these methyl acetamidomethyl groups promote the formation of a hydrogen-bonded dimer. This supramolecular complex catalyzes the reductive disproportionation of CO2 to CO and CO3(2-) at a lower overpotential (ca. 250 mV) than the corresponding single-site 2 e(-) reduction of CO2 to CO and H2O catalyzed by the corresponding model complex with a 4,4'-dimethyl-2,2'-bipyridyl ligand. These findings demonstrate that noncovalent self-assembly can modulate the catalytic properties of metal complexes by favoring alternate catalytic pathways.
authors.affiliation: Department of Chemistry and Biochemistry, University of California-San Diego , 9500 Gilman Drive, La Jolla, California 92093-0358, United States.
authors.forename: Charles W
authors.initials: CW
authors.lastname: Machan
authors.forename: Steven A
authors.initials: SA
authors.lastname: Chabolla
authors.forename: Jian
authors.initials: J
authors.lastname: Yin
authors.forename: Michael K
authors.initials: MK
authors.lastname: Gilson
authors.forename: F Akif
authors.initials: FA
authors.lastname: Tezcan
authors.forename: Clifford P
authors.initials: CP
authors.lastname: Kubiak
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002248:Carbon Monoxide / Q000138:chemical synthesis / Q000737:chemistry; D002384:Catalysis; D018360:Crystallography, X-Ray; D055664:Electrochemical Techniques; D046911:Macromolecular Substances / Q000138:chemical synthesis / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D011725:Pyridines / Q000737:chemistry; D012211:Rhenium / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D046911:Macromolecular Substances; D009942:Organometallic Compounds; D011725:Pyridines; D014867:Water; D002245:Carbon Dioxide; D012211:Rhenium; D002248:Carbon Monoxide