title: Biomimetic [2Fe-2S] clusters with extensively delocalized mixed-valence iron centers.
abstract: A complete series of biomimetic [2Fe-2S] clusters, [(L(Dep) Fe)2 (μ-S)2 ] (3, L(Dep) =CH[CMeN(2,6-Et2 C6 H3 )]2 ), [(L(Dep) Fe)2 (μ-S)2 K] (4), [(L(Dep) Fe)2 (μ-S)2 ][Bu4 N] (5, Bu=n-butyl), and [(L(Dep) Fe)2 (μ-S)2 K2 ] (6), could be synthesized and characterized. The all-ferric [2Fe-2S] cluster 3 is readily accessible through the reaction of [(L(Dep) Fe)2 (μ-H)2 ] (2) with elemental sulfur. The chemical reduction of 3 with one molar equivalent of elemental potassium affords the contact ion pair K(+) [2Fe-2S](-) (4) as a one-dimensional coordination polymer, which in turn reacts with [Bu4 N]Cl to afford the separate ion pair [Bu4 N](+) [2Fe-2S](-) (5). Further reduction of 4 with potassium furnishes the super-reduced all-ferrous [2Fe-2S] cluster 6. Remarkably, complexes 4 and 5 are [2Fe-2S] clusters with extensively delocalized Fe(2+) Fe(3+) pairs as evidenced by (57) Fe Mössbauer, X-ray absorption and emission spectroscopy (XAS, XES) and in accordance with DFT calculations.
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Shenglai
authors.initials: S
authors.lastname: Yao
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Florian
authors.initials: F
authors.lastname: Meier
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Nils
authors.initials: N
authors.lastname: Lindenmaier
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Robert
authors.initials: R
authors.lastname: Rudolph
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Burgert
authors.initials: B
authors.lastname: Blom
authors.affiliation: Lehrstuhl für Anorganische und Allgemeine Chemie, Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstrasse 1, 91058 Erlangen (Germany).
authors.forename: Mario
authors.initials: M
authors.lastname: Adelhardt
authors.affiliation: Lehrstuhl für Anorganische und Allgemeine Chemie, Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstrasse 1, 91058 Erlangen (Germany).
authors.forename: Jörg
authors.initials: J
authors.lastname: Sutter
authors.affiliation: Freie Universität Berlin, Fachbereich Physik, Arnimallee 14, 14195 Berlin (Germany).
authors.forename: Stefan
authors.initials: S
authors.lastname: Mebs
authors.affiliation: Freie Universität Berlin, Fachbereich Physik, Arnimallee 14, 14195 Berlin (Germany).
authors.forename: Michael
authors.initials: M
authors.lastname: Haumann
authors.affiliation: Lehrstuhl für Anorganische und Allgemeine Chemie, Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstrasse 1, 91058 Erlangen (Germany).
authors.forename: Karsten
authors.initials: K
authors.lastname: Meyer
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany).
authors.forename: Martin
authors.initials: M
authors.lastname: Kaupp
authors.affiliation: Technische Universität Berlin, Institut für Chemie, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin (Germany). matthias.driess@tu-berlin.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Driess
mesh_terms: D040761:Biomimetic Materials / Q000737:chemistry*; D058085:Iron Compounds / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011789:Quantum Theory
chemical_list: D058085:Iron Compounds; D007506:Iron-Sulfur Proteins
keywords: Rieske clusters; iron; mixed-valence compounds; sulfur; β-diketiminato ligands