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Characterization of a Borane ? Complex of a Diiron Dithiolate: Model for an Elusive Dihydrogen Adduct.

ABSTRACT: The azadithiolate complex Fe2[(SCH2)26NMe](CO)6 reacts with borane to give an initial 1:1 adduct, which spontaneously decarbonylates to give Fe2[(SCH2)2NMeBH3](CO)5. Featuring a Fe-H-B three-center, two-electron interaction, the pentacarbonyl complex is a structural model for H2 complexes invoked in the [FeFe]-hydrogenases. The pentacarbonyl compound is a "? complex", where a B-H ? bond serves as a ligand for iron. The structure of this ? complex was characterized by variable-temperature NMR spectroscopy and X-ray crystallography. Complementary to the 1:1 borane adduct is the quaternary ammonium complex [Fe2](SCH2)2NMe2](CO)6]+, which was also characterized. It represents a kinetically robust analogue of the N-protonated amine cofactor, as indicated by its mild reduction potential.

SUBMITTER: Lalaoui N

PROVIDER: S-EPMC5538135 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Characterization of a Borane σ Complex of a Diiron Dithiolate: Model for an Elusive Dihydrogen Adduct.

Lalaoui Noémie N Woods Toby T Rauchfuss Thomas B TB Zampella Giuseppe G

Organometallics 20170516 11

The azadithiolate complex Fe2[(SCH2)26NMe](CO)6 reacts with borane to give an initial 1:1 adduct, which spontaneously decarbonylates to give Fe2[(SCH2)2NMeBH3](CO)5. Featuring a Fe-H-B three-center, two-electron interaction, the pentacarbonyl complex is a structural model for H2 complexes invoked in the [FeFe]-hydrogenases. The pentacarbonyl compound is a "σ complex", where a B-H ...[more]

PMID: 28781407

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