RT info:eu-repo/semantics/article T1 (1,2-Azole)bis(bipyridyl)ruthenium(II) Complexes: Electrochemistry, Luminescent Properties, And Electro- And Photocatalysts for CO2 Reduction A1 Cuéllar, Elena A1 Pastor, Laura A1 García Herbosa, Gabriel A1 Nganga, John A1 Angeles-Boza, Alfredo M. A1 Diez Varga, Alberto A1 Torroba Pérez, Tomás A1 Martín-Alvarez, Jose M. A1 Miguel, Daniel A1 Villafañe, Fernando K1 Catalytic reactions K1 Electrochemical reduction K1 Ligands K1 Oxidation K1 Redox reactions K1 Química inorgánica K1 Chemistry, Inorganic AB New cis-(1,2-azole)-aquo bis(2,2′-bipyridyl)ruthenium(II) (1,2-azole (az*H) = pzH (pyrazole), dmpzH (3,5-dimethylpyrazole), and indzH (indazole)) complexes are synthesized via chlorido abstraction from cis-[Ru(bipy)2Cl(az*H)]OTf. The latter are obtained from cis-[Ru(bipy)2Cl2] after the subsequent coordination of the 1,2-azole. All the compounds are characterized by 1H, 13C, 15N NMR spectroscopy as well as IR spectroscopy. Two chlorido complexes (pzH and indzH) and two aquo complexes (indzH and dmpzH) are also characterized by X-ray diffraction. Photophysical and electrochemical studies were carried out on all the complexes. The photophysical data support the phosphorescence of the complexes. The electrochemical behavior of all the complexes in an Ar atmosphere indicate that the oxidation processes assigned to Ru(II) → Ru(III) occurs at higher potentials in the aquo complexes. The reduction processes under Ar lead to several waves, indicating that the complexes undergo successive electron-transfer reductions that are centered in the bipy ligands. The first electron reduction is reversible. The electrochemical behavior in CO2 media is consistent with CO2 electrocatalyzed reduction, where the values of the catalytic activity [icat(CO2)/ip(Ar)] ranged from 2.9 to 10.8. Controlled potential electrolysis of the chlorido and aquo complexes affords CO and formic acid, with the latter as the major product after 2 h. Photocatalytic experiments in MeCN with [Ru(bipy)3]Cl2 as the photosensitizer and TEOA as the electron donor, which were irradiated with >300 nm light for 24 h, led to CO and HCOOH as the main reduction products, achieving a combined turnover number (TONCO+HCOO–) as high as 107 for 2c after 24 h of irradiation. PB American Chemical Society SN 0020-1669 YR 2020 FD 2020-12 LK http://hdl.handle.net/10259/6817 UL http://hdl.handle.net/10259/6817 LA eng NO Junta de Castilla y León (ref. VA130618). E.C. thanks the UVa for her grant. The authors in Valladolid gratefully acknowledge financial support from the Spanish MINECO, Spain (PGC2018-099470-B-I00) and Junta de Castilla y León (VA130618), and the authors in Burgos gratefully acknowledge financial support from the Junta de Castilla y León, Consejería de Educación y Cultura and Fondo Social Europeo (Project BU263P18). A.M.A.-B. is grateful for support from the National Science Foundation CAREER Grant (CHE-1652606). DS Repositorio Institucional de la Universidad de Burgos RD 26-abr-2024