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Two Exceptional Homoleptic Iron(IV) Tetraalkyl Complexes.
Alicia Casitas1, Julian A Rees2,3, Richard Goddard1
1Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany.
Angewandte Chemie (International Ed. in English)
|March 3, 2017
Summary
The formation of a high-valent iron complex from Fe(II) is explained by intermediate disproportionation, driven by ligand interactions and strong Fe-C bonds. This stable complex defies expectations given its electronic configuration and potential for elimination reactions.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
Background:
- High-valent iron complexes are crucial in catalysis.
- Understanding their formation mechanisms is key to controlling reactivity.
Purpose of the Study:
- To elucidate the formation pathway of the high-valent iron complex [Fe(cyclohexyl)4].
- To explain the observed stability of this organoiron species.
Main Methods:
- Computational modeling to study reaction intermediates.
- Analysis of bonding and electronic structure.
Main Results:
- The formation is explained by disproportionation of a transient organoiron intermediate.
- Dispersive forces between cyclohexyl ligands and strong Fe-C bonds drive the reaction.
- The resulting diamagnetic complex (S=0) exhibits unexpected stability.
Conclusions:
- The stability is attributed to favorable ligand-ligand interactions and robust Fe-C bonds.
- The complex's stability challenges typical reactivity predictions based on electronic configuration and potential elimination pathways.
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