Ruthenium( II ) Octaphenylporphyrazine Complexes with Mixed Axial Ligands: Peculiarities of Their Formation and Spectral Properties

A series of new axially bis‐coordinated (octaphenylporphyrazinato)ruthenium( II ) complexes {[(Ph 8 Pz)RuL 2 ], L = cyclohexyl isocyanide, CyNC, ( 1b ); 4,4′‐bipyridine, bpy, ( 2c ); N ‐methylimidazole, CH 3 Im, ( 3a )} was prepared and characterized. The reaction of the bis‐isocyanide adducts [(Ph 8 Pz)Ru( t BuNC) 2 ] ( 1a ) or [(Ph 8 Pz)Ru(CyNC) 2 ] ( 1b ) with monodentate N‐heterocycles gave, under certain conditions, the mixed‐ligand complexes [(Ph 8 Pz)Ru(Py)( t BuNC)] ( 4a ), [(Ph 8 Pz)Ru(Py)(CyNC)] ( 4b ) and [(Ph 8 Pz)Ru(CH 3 Im)(CyNC)] ( 3b ). The reaction of 1a or 1b with an excess of bidentate 4,4′‐bipyridine under the same conditions resulted in the formation of the corresponding dimeric species [(Ph 8 Pz)Ru( t BuNC)] 2 (μ‐bpy) ( 2a ) and [(Ph 8 Pz)Ru(CyNC)] 2 (μ‐bpy) ( 2b ) in high yield. The structures of all the complexes were unambiguously proved by 1 H NMR spectroscopy, and the possibility of their self‐assembly is discussed. All mixed‐ligand compounds were also characterized by UV/Vis and IR spectroscopy, as well as elemental analysis. The 1 H NMR spectra of these compounds are discussed in detail. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)