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Cobalt in a bis-β-diketiminate environment
Michael P Marshak1, Matthew B Chambers, Daniel G Nocera
1Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA.
Inorganic Chemistry
|September 28, 2012
Summary
This study details the synthesis of a novel cobalt(II) complex with a planar, low-spin bis-β-diketiminate structure. Oxidation studies reveal the ligand
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Coordination Chemistry
Background:
- Bis-β-diketiminate ligands are versatile in coordination chemistry.
- Cobalt complexes exhibit diverse electronic and magnetic properties.
Purpose of the Study:
- To synthesize and characterize a novel bis-β-diketiminate cobalt(II) complex.
- To investigate the electronic structure and redox behavior of the cobalt complex.
- To explore the role of the ligand in redox processes.
Main Methods:
- Reaction of Co(2)(mesityl)(4) with acetonitrile.
- Electron Paramagnetic Resonance (EPR) spectroscopy.
- Magnetic susceptibility studies.
- Density Functional Theory (DFT) calculations.
- X-ray crystallography.
Main Results:
- Formation of a planar, low-spin, bis-β-diketiminate cobalt(II) complex, (1-mesitylbutane-1,3-diimine)(2)Co (1).
- Characterization of a (2)B(2)(d(yz))(1) ground state electronic configuration in a tetragonal ligand field.
- Successful oxidation to a cobalt(III) complex, (1-mesitylbutane-1,3-diimine)(2)Co(THF)(2)PF(6) (2).
- X-ray crystal structures indicate minimal changes in metal-ligand bond lengths upon oxidation, suggesting ligand participation.
Conclusions:
- The synthesized cobalt(II) complex exhibits a unique electronic configuration.
- The β-diketiminate ligand demonstrates redox non-innocence, participating in the oxidation event.
- This contrasts with typical redox non-innocent ligand behaviors, highlighting unique properties.
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