Elham Kianfar, Manuel Kaiser, Hrg. Günther Knör,
"Synthesis, Characterization and Photoreactivity of Rhenium and Molybdenum Carbonyl Complexes with Iminopyridine Ligands"
, in Journal of Organometallic Chemistry, Vol. 799-800, Seite(n) 13-18, 2015
Synthesis, Characterization and Photoreactivity of Rhenium and Molybdenum Carbonyl Complexes with Iminopyridine Ligands
Sprache des Titels:
In this report a series of novel rhenium tricarbonyl and molybdenum tetracarbonyl complexes containing pyridine-based 1,2-diimine ligands with low-lying pi-acceptor orbitals is
presented. All compounds display well-resolved chromophoric metal-to-ligand charge transfer (MLCT)bands in the visible spectral region. The rhenium(I) complexes (pyca-2,6-iPr2C6H3)Re(CO)3Cl (1),(pyca-2,6-Me2C6H3)Re(CO)3Cl (2), as well as the molybdenum(0) complexes (pyca-2,6-
iPr2C6H3)Mo(CO)4 (3), (pyca-2,6-Me2C6H3)Mo(CO)4 (4) and (pyca-2,4,6-Me3C6H2)Mo(CO)4 (5)
derived from pyridine-2-carboxaldehyde (pyca) are characterized by various spectroscopic methods.
Solid state structures of the complexes 1-5 determined by X-ray crystallography are described. While the rhenium complexes were found to be weakly luminescent both at 77 K and at 298 K as solid
materials or in solution, no authentic luminescence could be detected at 298 K for the molybdenum
carbonyl derivatives. Spectral changes indicating ligand substitution processes observed upon steadystate
irradiation of the compounds under full Xe-lamp light exposure and upon selective longwavelength
excitation in the MLCT-band region are also reported and briefly discussed.