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Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Platinum(II) and platinum(IV) complexes stabilized by abnormal/mesoionic C4-bound dicarbenes
Vsevolod Khlebnikov1, Marion Heckenroth, Helge Müller-Bunz
1School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
Dalton Transactions (Cambridge, England : 2003)
|December 6, 2012
Summary
New platinum complexes with abnormal diimidazolylidene ligands show unique solvolysis behavior and provide the first quantitative measure of the trans effect for these ligands. This discovery advances understanding of platinum carbene chemistry.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Carbene Ligand Development
Background:
- Platinum complexes are vital in catalysis and medicine.
- Abnormal carbene ligands offer unique electronic and steric properties.
- Understanding ligand effects on platinum reactivity is crucial.
Purpose of the Study:
- Synthesize novel platinum(II) complexes with abnormal diimidazolylidene ligands.
- Investigate the solvolysis behavior and trans effect of these complexes.
- Explore the reactivity of these complexes towards oxidation to platinum(IV).
Main Methods:
- Microwave-assisted C-H activation for synthesis.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural and kinetic analysis.
- Infrared (IR) spectroscopy and X-ray crystallography for characterization.
Main Results:
- Successful synthesis of platinum(II) complexes with abnormal diimidazolylidene ligands.
- Observed unusual solvent-induced solvolysis, with sulfur-bonding of DMSO.
- Quantified the trans effect of abnormal carbene ligands, showing rates comparable to phenylpyridine complexes.
- Synthesized platinum(IV) complexes, noting reduced solvolysis and observed linkage isomerism in Pt(IV)-bound DMSO.
Conclusions:
- Abnormal diimidazolylidene ligands exhibit distinct reactivity compared to normal carbene ligands.
- The trans effect of abnormal carbenes has been quantitatively measured for the first time.
- Platinum(IV) complexes show enhanced stability towards solvolysis compared to platinum(II) analogues.
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