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Reversible Single-Electron-Transfer to Oxygen in a Stable N-Heterocyclic Carbene Palladium(I) Metalloradical.

ABSTRACT: The chemical and electrochemical one-electron oxidation of [Pd(IPr)₂] (1) leads to the formation of mononuclear palladium(I) complex [Pd(IPr)₂][PF₆] (2). This bench-stable metalloradical has been fully characterized and its structure confirmed by X-ray diffraction analysis. EPR and DFT studies confirm the localization of the unpaired electron onto the metal center. Low temperature NMR and EPR measurements reveal the ability of complex 2 to reversibly coordinate and reduce the dioxygen molecule, leading to the formation of a three-coordinate complex, [Pd^II(IPr)₂(η¹-O₂)]⁺ (4), in which the unpaired electron has been transferred to the superoxido ligand.

SUBMITTER: Maties G

PROVIDER: S-EPMC10716904 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Reversible Single-Electron-Transfer to Oxygen in a Stable N-Heterocyclic Carbene Palladium(I) Metalloradical.

Maties Georgiana G Gómez-Sal Pilar P Yebra Cristina G CG Andrés Román R de Jesús Ernesto E

Inorganic chemistry 20231122 49

The chemical and electrochemical one-electron oxidation of [Pd(IPr)2] (1) leads to the formation of mononuclear palladium(I) complex [Pd(IPr)2][PF6] (2). This bench-stable metalloradical has been fully characterized and its structure confirmed by X-ray diffraction analysis. EPR and DFT studies confirm the localization of the unpaired electron onto the metal center. Low temperature NMR and EPR measurements reveal the ability of complex 2 to re ...[more]

PMID: 37992293

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