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Syntheses, spectroscopic, redox, and structural properties of homoleptic Iron(III/II) dithione complexes.

ABSTRACT: Two sets of Fe^III/II dithione complexes [Fe^II( ⁱ Pr₂Dt⁰)₃][PF₆]₂ ([1][PF₆]₂), [Fe^II(Me₂Dt⁰)₃][PF₆]₂ ([2][PF₆]₂), and [Fe^III( ⁱ Pr₂Dt⁰)₃][PF₆]₃ ([3][PF₆]₃), [Fe^III(Me₂Dt⁰)₃][PF₆]₃ ([4][PF₆]₃), and compound [Fe^III( ⁱ Pr₂Dt⁰)₃][FeCl₄][PF]₂ ([3][FeCl₄][PF₆]₂) were synthesized from N,N'-diisopropyl piperazine-2,3-dithione ( ⁱ Pr₂Dt⁰) and N,N'-dimethyl piperazine-2,3-dithione (Me₂Dt⁰) ligands. Complexes [1][PF₆]₂-[4][PF₆]₃ have been characterized by NMR, IR, and UV-visible spectroscopies, and by electrochemistry. The molecular structures of [2][PF₆]₂ and [3][FeCl₄][PF₆]₂ have been determined by X-ray crystallography. Complexes [2][PF₆]₂ and [3][FeCl₄][PF₆]₂ both crystallized in the monoclinic space group P2₁/n. Both complexes exhibit distorted octahedral geometry and the three coordinated ligands in each complex exhibit different dithione folding. Complexes [1][PF₆]₂-[4][PF₆]₃ exhibit a single Fe^III/II based couple and three quasi-reversible ligand-based redox couples. The electronic spectra of [1][PF₆]₂-[4][PF₆]₃ show intense MLCT bands that indicate strong mixing between metal and ligand orbitals. DFT calculations were used to provide a framework for understanding the electronic origin of their redox chemistry and spectroscopic features.

SUBMITTER: Colston KJ

PROVIDER: S-EPMC9057267 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Syntheses, spectroscopic, redox, and structural properties of homoleptic Iron(III/II) dithione complexes.

Colston Kyle J KJ Dille Sara A SA Mogesa Benjamin B Brant Jacilynn J Nemykin Victor N VN Zeller Matthias M Basu Partha P

RSC advances 20201016 63

Two sets of FeIII/II dithione complexes [FeII( i Pr2Dt0)3][PF6]2 ([1][PF6]2), [FeII(Me2Dt0)3][PF6]2 ([2][PF6]2), and [FeIII( i Pr2Dt0)3][PF6]3 ([3][PF6]3), [FeIII(Me2D ...[more]

PMID: 35517554

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Dataset Information

Syntheses, spectroscopic, redox, and structural properties of homoleptic Iron(III/II) dithione complexes.

Publications

Syntheses, spectroscopic, redox, and structural properties of homoleptic Iron(III/II) dithione complexes.

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