Bonding of η1-Acetylide Ligands to Electron-Rich Ruthenium Centers: Can Electron-Withdrawing Ligands Induce Significant Metal-to-Ligand Back-Bonding?

Citations Over TimeTop 10% of 1997 papers

Abstract

The electronic structure of a series of η1-acetylide complexes containing electron-rich ruthenium centers is examined using approximate density functional theory. Calculations are performed on two series of complexes, Ru(C⋮CR)(PH3)2(η5-C5H5) and trans-Ru(C⋮CR)Cl(PH3)4, with a series of substituted acetylide ligands, R = H, C6H5 and C6H4-4-NO2. The π back-bonding ability of the ligands increases in the order R = H < C6H5 < C6H4-4-NO2, while π donor properties vary as R = H < C6H4-4-NO2 < C6H5. The cations of the complexes of the phenylacetylide ligand are therefore relatively stable, particularly when the vacancy at the metal center arises in an orbital coplanar with the phenyl π system. The nitrophenylacetylide ligand is a much weaker σ donor than either of the other two. Trends in calculated ionization energies result from a subtle interplay of changes in the σ donor, π donor, and π acceptor properties of the ligands and cannot be ascribed to one mechanism in isolation.

Related Papers

• → Synthesis and characterisation of mono-acetylide and unsymmetrical bis-acetylide complexes of ruthenium and osmium: X-ray structure determinations on [(dppe)2Ru(Cl)(CC–C6H4-p-NO2)], [(dppe)2Ru(Cl)(CC–C6H3-o-CH3-p-NO2)] and [(dppm)2Os(CC–C6H4-p-CH3)(CC–C6H4-p-NO2)](1999)59 cited
• → Ligand control of metal oxidation states. Synthesis, characterization and cyclic voltammetric studies of a group of ruthenium phenolates(1996)18 cited
• THE FEATURES OF PROTEIN BINDING BY RUTHENIUM COMPLEXES: DOCKING, FORCE FIELD AND QM/MM STUDIES(2013)
• → Phosphorogenic and spontaneous formation of tris(bipyridine)ruthenium in peptide scaffolds(2019)1 cited
• → ChemInform Abstract: Mixed Metal Acetylide Complexes(2008)