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Updated: May 20, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Comparative study of C^N and N^C type cyclometalated ruthenium complexes with a NAD+/NADH function
Sumanta Kumar Padhi1, Ryoichi Fukuda, Masahiro Ehara
1Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1, Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan.
Inorganic Chemistry
|July 26, 2012
Summary
Ruthenium complexes with C(^)N and N(^)C ligands were synthesized. Ligand coordination position drastically altered properties, with one complex showing photochemical reduction and tautomeric equilibrium, unlike the other.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Photochemistry
Background:
- Cyclometalated ruthenium complexes are valuable in catalysis and photochemistry.
- Understanding ligand coordination effects is crucial for tuning complex properties.
- NAD+/NADH mimics are important for biomimetic studies.
Purpose of the Study:
- To synthesize and characterize cyclometalated ruthenium complexes with C(^)N and N(^)C ligands.
- To investigate the impact of coordinating atom position on complex redox and photochemical properties.
- To explore the behavior of protonated complexes, including potential N-heterocyclic carbene formation.
Main Methods:
- Synthesis of ruthenium complexes.
- Spectroscopic characterization (NMR, Mass Spectrometry, UV-Vis).
- Chemical and electrochemical reduction studies.
- Photochemical reduction experiments.
- Theoretical calculations (DFT).
Main Results:
- Two cyclometalated ruthenium complexes, [1]PF(6) and [2]PF(6), were synthesized and characterized.
- Complex [1]PF(6) underwent successful photochemical reduction, while [2]PF(6) did not.
- Protonation of ligands stabilized π* orbital energy levels.
- Protonated complex [2H](PF(6))(2) exhibited tautomeric equilibrium and behaved as a remote N-heterocyclic carbene (rNHC) complex, unlike [1H](PF(6))(2).
Conclusions:
- The coordinating position of the σ-donating carbon atom significantly influences the properties of cyclometalated ruthenium complexes.
- Photochemical reduction is feasible for certain ruthenium complexes, dependent on ligand structure.
- Protonation can induce unique reactivity, such as rNHC behavior in specific ruthenium complexes.
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