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Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
A trans-1,2 End-On Disulfide-Bridged Iron-Tetracarbene Dimer and Its Electronic Structure
Steffen Meyer1, Oliver Krahe2, Claudia Kupper1
1Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
Abstract:
A disulfide-bridged diiron complex with [Fe-S-S-Fe] core, which represents an isomer of the common biological [2Fe-2S] ferredoxin-type clusters, was synthesized using strongly σ-donating macrocyclic tetracarbene capping ligands. Though the complex is quite labile in solution, single crystals were obtained, and the structure was elucidated by X-ray diffraction. The electron-rich iron-sulfur core is found to show rather unusual magnetic and electronic properties. Experimental data and density functional theory studies indicate extremely strong antiferromagnetic coupling (-J > 800 cm(-1)) between two low-spin iron(III) ions via the S2(2-) bridge, and the intense near-IR absorption characteristic for the [Fe-S-S-Fe] core was assigned to a S → Fe ligand-to-metal charge transfer transition.
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