Hangman corroles: efficient synthesis and oxygen reaction chemistry
Dilek K Dogutan1, Sebastian A Stoian, Robert McGuire
1Department of Chemistry, 6-335, Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA.
Journal of the American Chemical Society
|December 15, 2010
Summary
New hangman corroles efficiently activate oxygen-oxygen bonds. These cobalt corrole compounds demonstrate enhanced catalytic activity for reducing oxygen to water, outperforming unmodified versions.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Supramolecular Chemistry
Background:
- Corroles are macrocyclic ligands with unique electronic properties.
- Hangman ligands incorporate a proton donor near the metal center.
- Cobalt corroles are investigated for catalytic applications.
Purpose of the Study:
- To synthesize a novel class of hangman cobalt corroles.
- To investigate the electronic structure of high oxidation states.
- To evaluate their catalytic activity in oxygen-oxygen bond activation.
Main Methods:
- Modification of macrocyclic forming reactions from bilanes.
- One-pot condensation and metal insertion using microwave irradiation.
- X-band Electron Paramagnetic Resonance (EPR) spectroscopy and Density Functional Theory (DFT) calculations.
Main Results:
- Efficient synthesis of hangman cobalt corroles in good yields.
- Characterization of high oxidation states consistent with Co(III) in a one-electron oxidized macrocycle.
- Demonstrated enhanced catalytic activity for selective oxygen reduction to water.
Conclusions:
- Hangman corroles provide a new platform for catalytic O-O bond activation.
- The proton-donating group and redox properties synergize for enhanced catalysis.
- These compounds show promise for efficient oxygen reduction reactions.
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