Standort: ---
Exemplare:
---
| Online-Ressource |
Verfasst von: | Lohmeyer, Lukas [VerfasserIn]  |
| Kaifer, Elisabeth [VerfasserIn]  |
| Enders, Markus [VerfasserIn]  |
| Himmel, Hans-Jörg [VerfasserIn]  |
Titel: | Switching from metal- to ligand-based oxidation in cobalt complexes with redox-active bisguanidine ligands |
Verf.angabe: | Lukas Lohmeyer, Elisabeth Kaifer, Markus Enders, and Hans-Jörg Himmel |
Jahr: | 2021 |
Umfang: | 16 S. |
Fussnoten: | First published: 08 June 2021 ; Gesehen am 25.11.2022 |
Titel Quelle: | Enthalten in: Chemistry - a European journal |
Ort Quelle: | Weinheim : Wiley-VCH, 1995 |
Jahr Quelle: | 2021 |
Band/Heft Quelle: | 27(2021), 46, Seite 11852-11867 |
ISSN Quelle: | 1521-3765 |
Abstract: | The control of the redox reactivity, magnetic and optical properties of the different redox states of complexes with redox-active ligands permits their rational use in catalysis and materials science. The redox-chemistry of octahedrally coordinated high-spin CoII complexes (three unpaired electrons) with one redox-active bisguanidine ligand and two acetylacetonato (acac) co-ligands is completely changed by replacing the acac by hexafluoro-acetylacetonato (hfacac) co-ligands. The first one-electron oxidation is metal-centered in the case of the complexes with acac co-ligands, giving diamagnetic CoIII complexes. By contrast, in the case of the less Lewis-basic hfacac co-ligands, the first one-electron oxidation becomes ligand-centered, leading to high-spin CoII complexes with a radical monocationic guanidine ligand unit (four unpaired electrons). Ferromagnetic coupling between the spins on the metal and the organic radical in solution is evidenced by temperature-dependent paramagnetic NMR studies, allowing to estimate the isotropic exchange coupling constant in solution. Second one-electron oxidation leads to high-spin CoII complexes with dicationic guanidine ligand units (three unpaired electrons) in the presence of hfacac co-ligands, but to low-spin CoIII complexes with radical monocationic, peralkylated guanidine ligand (one unpaired electron) in the presence of acac co-ligands. The analysis of the electronic structures is complemented by quantum-chemical calculations on the spin density distributions and relative energies of the possible redox isomers. |
DOI: | doi:10.1002/chem.202101364 |
URL: | kostenfrei: Volltext: https://doi.org/10.1002/chem.202101364 |
| kostenfrei: Volltext: https://onlinelibrary.wiley.com/doi/abs/10.1002/chem.202101364 |
| DOI: https://doi.org/10.1002/chem.202101364 |
Datenträger: | Online-Ressource |
Sprache: | eng |
Sach-SW: | cobalt |
| guanidine |
| oxidation |
| radical ligands |
| redox-active ligand |
K10plus-PPN: | 1823668585 |
Verknüpfungen: | → Zeitschrift |
|
|
| |
Lokale URL UB: | Zum Volltext |
Switching from metal- to ligand-based oxidation in cobalt complexes with redox-active bisguanidine ligands / Lohmeyer, Lukas [VerfasserIn]; 2021 (Online-Ressource)
68989124