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Updated: Jun 12, 2025
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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
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A homoleptic Fe(iv) ketimide complex with a low-lying excited state
Phoebe R Hertler1, Arturo Sauza-de la Vega2, Andrea Darù2
1Department of Chemistry and Biochemistry, University of California Santa Barbara Santa Barbara CA 93106 USA hayton@chem.ucsb.edu.
Chemical Science
|September 23, 2024
Summary
Researchers synthesized a new iron complex, [Fe(N[double bond, length as m-dash]C( Bu)Ph)4], demonstrating a rare Fe(IV) oxidation state. This square planar complex exhibits an S=0 ground state with a close-lying S=1 excited state.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Materials Science
Background:
- Iron complexes with bulky ligands are crucial in catalysis.
- Understanding high oxidation states in iron is key to developing new reactivity.
- The synthesis and characterization of Fe(IV) complexes are of significant interest.
Purpose of the Study:
- To synthesize and characterize a novel iron complex with a high oxidation state.
- To investigate the electronic structure and magnetic properties of the synthesized complex.
- To explore the potential for new iron-based catalytic systems.
Main Methods:
- Reaction of Li(N[double bond, length as m-dash]C( Bu)Ph) with FeIICl2 followed by oxidation with I2.
- 57Fe Mössbauer spectroscopy to confirm the iron oxidation state.
- X-ray crystallography to determine the molecular structure and coordination geometry.
- SQUID magnetometry to probe magnetic properties.
- Density functional theory (DFT) and multiconfigurational calculations for electronic structure analysis.
Main Results:
- Successful synthesis of [Li(Et2O)]2[FeII(N[double bond, length as m-dash]C( Bu)Ph)4] and [FeIV(N[double bond, length as m-dash]C( Bu)Ph)4].
- 57Fe Mössbauer spectroscopy confirmed the Fe(IV) oxidation state in the latter complex.
- X-ray crystallography revealed a square planar geometry for the Fe(IV) complex with intramolecular H⋯C interactions.
- SQUID magnetometry indicated a small magnetic moment, suggesting an accessible S = 1 state.
- Computational studies identified an S = 0 ground state with a closely lying S = 1 excited state.
Conclusions:
- A novel square planar Fe(IV) complex, [Fe(N[double bond, length as m-dash]C( Bu)Ph)4], has been synthesized and characterized.
- The complex exhibits interesting electronic and magnetic properties, with an S = 0 ground state and an accessible S = 1 excited state.
- This work contributes to the understanding of high-valent iron chemistry and may inform the design of new functional materials.
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