Cyclometalated ruthenium chloro and nitrosyl complexes

Area of Science:

• Inorganic Chemistry
• Organometallic Chemistry
• Coordination Chemistry

Background:

• Ruthenium complexes are vital in catalysis and materials science.
• Cyclometalated complexes offer unique electronic and structural properties.
• Nitrosyl complexes of ruthenium are important in bioinorganic and catalytic applications.

Purpose of the Study:

• To synthesize and characterize novel cyclometalated and nitrosyl ruthenium complexes.
• To investigate the structural and electronic properties of these new compounds.
• To explore the influence of ligand arrangement on complex stability and reactivity.

Main Methods:

• Synthesis of ruthenium complexes [Ru(eta(2)-phpy)(trpy)Cl][PF(6)].toluene and [Ru(eta(2)-phpy)(trpy)NO][PF(6)](2).
• Characterization using elemental analysis, IR, (1)H NMR, electronic absorption spectroscopy, and cyclic voltammetry.
• Determination of crystal structures for both complexes.

Main Results:

• The crystal structure of the cyclometalated complex showed a chloride ion trans to the sigma-bonding phenyl group, forming a stable paramagnetic species.
• The crystal structure of the nitrosyl complex revealed the nitrosyl ligand trans to the sigma-bonding phenyl group.
• A significant distortion in the Ru-NO bond angle was observed in the nitrosyl complex, attributed to the phenyl group's electronic properties.

Conclusions:

• The study successfully synthesized and characterized two novel ruthenium complexes with distinct structural features.
• The findings highlight the unusual stability of the paramagnetic cyclometalated complex.
• The research provides insights into the electronic effects of ligands on ruthenium complex geometry and bonding.