Effect of second-sphere coordination 13. Consideration of factors affecting adduct formation of ruthenium–ammine complexes with crown ethers based on the stability constants

• Stability was determined for crown ether adduct of ruthenium–ammine complexes.
• Factors affected the stability and the change in redox potential in a different way.
• Flexibility of crown ether ring.
• Strength and the number of hydrogen bonding.
• π-Electron acceptability of ancillary ligand.

Adduct formation was systematically investigated for ruthenium–ammine complex and crown ether systems. This study involved crown ether systems with different flexibility, the complex system with different numbers of ammine ligands, and the pentaammine complexes systems with aromatic ligands with different π-electron acceptability. Stability constants of the crown-ether adduct of the complexes were determined for the above systems by 1H NMR spectroscopy. The factors affecting adduct formation were discussed on basis of the stability constant.

Adduct formation was systematically investigated for ruthenium–ammine complexes with crown ethers. Factors affecting the stability of adduct and redox potential of the complex were ascertained based on the stability constants: the flexibility of crown ether ring, the number of possible hydrogen bonding, the strength of hydrogen bonding, and the π-electron acceptability of ancillary ligand.Figure optionsDownload as PowerPoint slide