Synthesis and structural characterization of new piano-stool ruthenium(II) complexes bearing 1-butylimidazole heteroaromatic ligand

摘要

New cationic ruthenium(II) complexes with the formula [Ru(η ~5-C _5H _5)(LL)(1-BuIm)] [Z], with (LL) = 2PPh _3 or DPPE, and Z = CF _3SO _3 ~-, PF _6 ~-, BPh _4 ~-, have been synthesized and fully characterized. Spectroscopic and electrochemical studies revealed that the electronic properties of the coordinated 1-butylimidazole were clearly influenced by the nature of the phosphane coligands (LL) and also by the different counter ions. The solid state structures of the six complexes determined by X-ray crystallographic studies, confirmed the expected distorted three-legged piano stool structure. However the geometry of the 1-butylimidazole ligand was found considerably different in all six compounds, being governed by the stereochemistry of the mono and bidentate coligands (PPh _3 or DPPE).