X-ray structure, electronic properties and density functional calculations: trans-Dihalo (1-(4-phenylimino)-1-(phenylhydrazono)-propan-2-one) (4,4′-di-tert-butyl-2,2-bipyridine) ruthenium(II) complexes

The reaction of RuX3 (X = F, CI, Br) with arylazoimine (PhNNC(COCH3)NPh, Az) and (4,4′-di-tert-butyl-2,2-bipyridine, dtb) in refluxing ethanol affords a trans-[Ru(Az)(dtb)X2]. These complexes have been characterized through spectroscopic (IR, UV/Vis, and NMR) and electrochemical (CV) techniques. The complex trans-[Ru(Az)(dtb)Cl2] has been X-ray crystallographically characterized. The crystals belong to the rhombohedral space group R3¯. The two chlorine atoms are trans to each other. The 4,4′-di-tert-butyl-2,2-bipyridine ligand is bent and the Az ligand rings are rotated, due to inter-ligands steric interactions between H atoms of opposite pyridyl units across the Ru center. These complexes display a cyclic voltammetric one-electron metal oxidation peak in acetonitrile near 1.2 V versus NHE. The electronic absorption spectra of these complexes show a strong band in the visible region which is assigned to a (Ru(II)-to-azomethine) MLCT transition based on TD-DFT calculations.

The reaction of RuX3 (X = CI, Br, I) with arylazoimine (PhNNC(COCH3)NPh, Az) and (4,4′-di-tert-butyl-2,2-bipyridine, dtb) in refluxing ethanol affords a trans-[Ru(Az)(dtb)X2]. These complexes have been characterized through spectroscopic (IR, UV/Vis, and NMR) and electrochemical (CV) techniques. The complex trans-[Ru(Az)(dtb)Cl2] has been X-ray crystallographically characterized. The crystals belong to the rhombohedral space group R3¯. The two chlorine atoms are trans to each other. These complexes display a cyclic voltammetric one-electron metal oxidation peak in acetonitrile near 1.2 V versus NHE. The electronic absorption spectra of these complexes show a strong band in the visible region which is assigned to a (Ru(II)-to-azomethine) MLCT transition based on TD-DFT calculations.Figure optionsDownload as PowerPoint slide