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Updated: May 6, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
11.0K
Iron(II) complexes of ditopic carbanionic carbenes
Rebecca A Musgrave1, Robert S P Turbervill, Mark Irwin
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford OX1 3TA, UK. jose.goicoechea@chem.ox.ac.uk.
Dalton Transactions (Cambridge, England : 2003)
|November 5, 2013
Summary
Novel trigonal planar iron complexes with N-heterocyclic carbenes were synthesized and characterized. These complexes exhibit quintet ground states and undergo reduction to form anionic species, some of which react with triethylaluminium.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Iron complexes are crucial in catalysis and materials science.
- N-heterocyclic carbenes (NHCs) are versatile ligands in organometallic chemistry.
- Understanding the electronic and structural properties of low-valent iron complexes is key.
Purpose of the Study:
- To synthesize and characterize novel trigonal planar iron(II) complexes with N-heterocyclic carbenes.
- To investigate the reactivity of these complexes, particularly their reduction products.
- To explore the coordination behavior of anionic iron complexes with Lewis acids.
Main Methods:
- Synthesis of iron(II) complexes with IPr and 6-Xyl NHCs.
- Single crystal X-ray diffraction for structural characterization.
- Magnetic susceptibility measurements.
- Reductive chemistry using KC8 and reactions with triethylaluminium.
Main Results:
- Formation of trigonal planar [Fe(IPr)(mes)2] and [Fe(6-Xyl)(mes)2] complexes.
- Characterization of quintet ground states (S=2) for both complexes.
- Synthesis of anionic complexes [Fe(NHC)2(mes)]- and [Fe(mes)3]-.
- Coordination of triethylaluminium to anionic NHC-iron complexes.
Conclusions:
- Novel low-coordinate iron complexes with NHCs can be synthesized.
- These complexes exhibit interesting electronic properties and reactivity.
- The anionic iron complexes serve as platforms for further functionalization with Lewis acids.
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