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A Molecular Low-Coordinate [Fe-S-Fe] Unit in Three Oxidation States.

ABSTRACT: A [Fe-S-Fe] subunit with a single sulfide bridging two low-coordinate iron ions is the supposed active site of the iron-molybdenum co-factor (FeMoco) of nitrogenase. Here we report a dinuclear monosulfido bridged diiron(II) complex with a similar complex geometry that can be oxidized stepwise to diiron(II/III) and diiron(III/III) complexes while retaining the [Fe-S-Fe] core. The series of complexes has been characterized crystallographically, and electronic structures have been studied using, inter alia, ⁵⁷ Fe Mössbauer spectroscopy and SQUID magnetometry. Further, cleavage of the [Fe-S-Fe] unit by CS₂ is presented.

SUBMITTER: Schneider C

PROVIDER: S-EPMC8048577 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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A Molecular Low-Coordinate [Fe-S-Fe] Unit in Three Oxidation States.

Schneider Christian C Demeshko Serhiy S Meyer Franc F Werncke C Gunnar CG

Chemistry (Weinheim an der Bergstrasse, Germany) 20210305 20

A [Fe-S-Fe] subunit with a single sulfide bridging two low-coordinate iron ions is the supposed active site of the iron-molybdenum co-factor (FeMoco) of nitrogenase. Here we report a dinuclear monosulfido bridged diiron(II) complex with a similar complex geometry that can be oxidized stepwise to diiron(II/III) and diiron(III/III) complexes while retaining the [Fe-S-Fe] core. The series of complexes has been characterized crystallographically, and electronic structures have been studied using, in ...[more]

PMID: 33512018

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