Luminescent cis-Bis(bipyridyl)ruthenium(II) Complexes with 1,2-Azolylamidino Ligands: Photophysical, Electrochemical Studies, and Photocatalytic Oxidation of Thioethers

New 1,2-azolylamidino complexes cis-[Ru(bipy)2(NH=C(R)az*-κ2N,N)](OTf)2 (R = Me, Ph; az∗ = pz, indz, dmpz) are synthesized via chloride abstraction after a subsequent base-catalyzed coupling of a nitrile with the previously coordinated 1,2-azole. The synthetic procedure allows the easy obtainment of...

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Detalles Bibliográficos
Autores: Cuéllar, Elena, Diez-Varga, Alberto, Torroba, Tomás, Domingo-Legarda, Pablo, Alemán Lara, José Julián, Cabrera Herranz, Silvia, Martín-Alvarez, Jose M., Miguel, Daniel, Villafañe, Fernando
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/704759
Acceso en línea:http://hdl.handle.net/10486/704759
https://dx.doi.org/10.1021/acs.inorgchem.0c03389
Access Level:acceso abierto
Palabra clave:Catalytic Performance
Chloride Abstraction
Electrochemical Studies
Oxidation Reactions
Photocatalytic Oxidations
Photophysical Studies
Ruthenium Complexes
Synthetic Procedures
Química
Descripción
Sumario:New 1,2-azolylamidino complexes cis-[Ru(bipy)2(NH=C(R)az*-κ2N,N)](OTf)2 (R = Me, Ph; az∗ = pz, indz, dmpz) are synthesized via chloride abstraction after a subsequent base-catalyzed coupling of a nitrile with the previously coordinated 1,2-azole. The synthetic procedure allows the easy obtainment of complexes having different electronic and steric 1,2-azoylamidino ligands. All of the compounds have been characterized by 1H, 13C, and 15N NMR and IR spectroscopy and by monocrystal X-ray diffraction. Photophysical studies support their phosphorescence, whereas their electrochemistry reveals reversible RuII/RuIII oxidations between +1.13 and +1.25 V (vs SCE). The complexes have been successfully used as catalysts in the photooxidation of different thioethers, the complex cis-[Ru(bipy)2(NH=C(Me)dmpz-κ2N,N)]2+ showing better catalytic performance in comparison to that of [Ru(bipy)3]2+. Moreover, the significant catalytic performance of the dimethylpyrazolylamidino complex is applied to the preparation of the drug modafinil, which is obtained using ambient oxygen as an oxidant. Finally, mechanistic assays suggest that the oxidation reaction follows a photoredox route via oxygen radical anion formation.