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Dinuclear iron complexes based on parallel beta-diiminato binding sites: syntheses, structures and reaction with O2
Maurice Frederic Pilz1, Christian Limberg, Serhiy Demeshko
1Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, D-12489, Berlin, Germany.
Dalton Transactions (Cambridge, England : 2003)
|March 29, 2008
Summary
This study explores iron complexes with a xanthene backbone for oxygen activation, mimicking natural systems. The synthesized iron complexes readily react with O2, forming iron oxides with antiferromagnetic coupling.
Area of Science:
- Coordination Chemistry
- Bioinorganic Chemistry
- Materials Science
Background:
- Natural systems use di-iron centers for oxygen activation.
- Investigated a xanthene-linked bis(beta-diiminato) ligand system for Fe(II) coordination.
Purpose of the Study:
- To synthesize and characterize iron(II) complexes with the [RXanthdim]2- ligand.
- To investigate their reactivity towards O2 activation.
- To study the structural and magnetic properties of the resulting complexes.
Main Methods:
- Synthesis of lithium salts and subsequent reaction with FeCl2 to form iron(II) complexes.
- Reaction of iron complexes with O2 to yield iron(III) oxides.
- Single crystal X-ray diffraction for structural determination.
- Magnetic property investigations.
Main Results:
- Successfully synthesized and characterized two iron(II) complexes, [Me2C6H3Xanthdim]Fe2Cl3(Li(thf)3) and [F2C6H3Xanthdim]Fe2Cl3(Li(thf)3).
- These complexes react with O2 to form iron(III) oxides with Fe(III)-O-Fe(III) moieties.
- Structural analysis revealed specific coordination environments.
- Antiferromagnetic coupling was observed between the two iron centers in all investigated complexes.
Conclusions:
- The synthesized ligand system effectively coordinates iron(II) centers for O2 activation studies.
- The resulting iron oxides exhibit antiferromagnetic interactions, influenced by ligand substituents.
- This work provides insights into the coordination chemistry and reactivity of di-iron systems relevant to O2 activation.
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