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Updated: Jun 11, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Functionalisation of terpyridine complexes containing the Re(CO)3(+) moiety
Angelo J Amoroso1, Afrosa Banu, Michael P Coogan
1School of Chemistry, Cardiff University, PO Box 912, Cardiff, UKCF10 3AT. amorosoaj@cf.ac.uk
Dalton Transactions (Cambridge, England : 2003)
|June 29, 2010
Summary
This study explores substitution reactions of rhenium complexes. Chloride ligands in rhenium-terpyridine complexes can be substituted with acetonitrile, but methylation affects reactivity, requiring iodide substitution for similar transformations.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Rhenium Complexes
Background:
- Rhenium complexes with polypyridyl ligands are of interest due to their unique electronic and photophysical properties.
- Understanding ligand substitution pathways is crucial for designing functional materials and catalysts.
Purpose of the Study:
- To investigate the substitution and addition chemistry of rhenium(I) complexes containing sigma(2)-terpyridine ligands.
- To explore the influence of ligand methylation on the reactivity of the chloride ligand.
- To examine the lability of acetonitrile ligands in substituted rhenium complexes.
Main Methods:
- Synthesis of rhenium(I)-terpyridine complexes, including methylated derivatives.
- Substitution reactions involving chloride and iodide ligands with acetonitrile.
- Characterization of resulting complexes using spectroscopic techniques (implied).
Main Results:
- The chloride ligand in Re(sigma(2)-terpy)(CO)(3)Cl can be substituted by acetonitrile.
- Substitution of chloride in the methylated analogue [Re(sigma(2)-terpyMe)(CO)(3)Cl][PF(6)] was unsuccessful under standard conditions.
- Using the corresponding iodide complex [Re(sigma(2)-terpyMe)(CO)(3)I][PF(6)] allowed for successful substitution with acetonitrile.
- The acetonitrile ligand in [Re(sigma(2)-terpy)(CO)(3)(CH(3)CN)][PF(6)] is labile and can be replaced by pyridine donors.
Conclusions:
- The reactivity of the halide ligand in these rhenium complexes is sensitive to the electronic properties of the terpyridine ligand, particularly upon methylation.
- Iodide is a more effective leaving group than chloride in the methylated system for acetonitrile substitution.
- The lability of the acetonitrile ligand offers further opportunities for functionalization of these rhenium complexes.
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