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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
The reactivity patterns of low-coordinate iron-hydride complexes
Ying Yu1, Azwana R Sadique, Jeremy M Smith
1Department of Chemistry, University of Rochester, Rochester, New York, 14627, USA.
Journal of the American Chemical Society
|May 1, 2008
Summary
This study explores reactions of low-coordinate iron-hydride complexes. These complexes undergo addition, reductive elimination, or protonation, yielding diverse iron products and offering insights into nitrogenase enzyme mechanisms.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Bioinorganic Chemistry
Background:
- Low-coordinate, high-spin iron(II) complexes are rare but crucial for understanding catalytic processes.
- Iron-hydride complexes are implicated in biological nitrogen fixation.
Purpose of the Study:
- To investigate the reactivity of the first isolable iron-hydride complexes with coordination numbers less than 5.
- To characterize the products and reaction pathways of these complexes with various substrates.
- To provide insights into the potential role of similar iron species in nitrogenase enzymes.
Main Methods:
- Synthesis and characterization of high-spin iron(II) complexes with beta-diketiminate ligands.
- Survey of reactivity with substrates including cyanides, isocyanides, alkynes, N2, alkenes, and Brønsted acids.
- Analysis of reaction products using spectroscopic and structural methods.
Main Results:
- The iron-hydride complexes react rapidly with a diverse range of substrates.
- Reactions proceed via three main pathways: Fe-H addition, H2 reductive elimination, or hydride protonation.
- A variety of new iron complexes, including imide, formate, and triazenido species, were formed.
Conclusions:
- The study establishes the reactivity profile of low-coordinate iron-hydride complexes.
- The findings expand the known scope of iron-mediated bond transformations.
- The results offer valuable mechanistic insights relevant to the iron-molybdenum cofactor of nitrogenases.
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