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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Metallabenzene versus Cp complex formation: a DFT investigation.
Mark A Iron1, Jan M L Martin, Milko E van der Boom
1Department of Organic Chemistry, Weizmann Institute of Science, 76100 Rehovot, Israel.
Journal of the American Chemical Society
|October 23, 2003
Summary
Density functional theory investigated metallabenzene reactions, revealing a carbene migratory insertion pathway to cyclopentadienyl (Cp) complexes. While Cp complexes are generally favored, specific iridium complexes show metallabenzene stability, suggesting potential isolation of novel rhodiabenzene and palladiabenzene compounds.
Area of Science:
- Organometallic Chemistry
- Computational Chemistry
Background:
- Metallaarene complexes commonly transform into cyclopentadienyl (Cp) complexes.
- Understanding the reaction mechanisms is crucial for synthetic control.
Purpose of the Study:
- To investigate the reaction mechanism of metallabenzene to Cp complex formation using computational methods.
- To identify factors influencing the thermodynamic favorability of Cp versus metallabenzene products.
Main Methods:
- Density functional theory (DFT) calculations were employed.
- Analysis of reaction pathways, including carbene migratory insertion and C-C coupling.
Main Results:
- The reaction proceeds via a carbene migratory insertion mechanism.
- Cyclopentadienyl (Cp) complexes are generally thermodynamically favored.
- An exception was observed for (C5H5Ir)(PH3)2Cl2 (1j), where the metallabenzene isomer is favored.
Conclusions:
- The DFT study elucidates the mechanism of metallabenzene conversion to Cp complexes.
- Thermodynamic analysis predicts the stability of different product types.
- The findings suggest the potential for isolating novel rhodiabenzene and palladiabenzene complexes.
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