{trans-1,4-Bis[(4-pyridyl)ethenyl]benzene}(2,2‘-bipyridine)ruthenium(II) Complexes And Their Supramolecular Assemblies With β-Cyclodextrin by Sergio H. Toma , Miriam Uemi , Sofia Nikolaou , Daniela M. Tomazela , Marcos N. Eberlin , and Henrique E. Toma, Inorganic Chemistry, 43(11): 3521-3527 (4th May 2004)
Why is this reaction purpose made for Ratz? The authors' own illustration tells the story ...Toma et al, 2004 wrote:Two novel ruthenium polypyridine complexes, [Ru(bpy)2Cl(BPEB)](PF6) and {[Ru(bpy)2Cl]2(BPEB)}(PF6)2 (BPEB = trans-1,4-bis[2-(4-pyridyl)ethenyl]benzene), were synthesized and their characterization carried out by means of elemental analysis, UV−visible spectroscopy, positive ion electrospray (ESI-MS), and tandem mass (ESI-MS/MS) spectrometry, as well as by NMR spectroscopy and cyclic voltammetry. Cyclic and differential pulse voltammetry for the mononuclear complex showed three set of waves around 1.2 V (Ru2+/3+), −1.0 V (BPEB0/-), and −1.15 (BPEB-/2-). This complex exhibited aggregation phenomena in aqueous solution, involving π−π stacking of the planar, hydrophobic BPEB ligands. According to NMR measurements and variable-temperature experiments, the addition of β-cyclodextrin (βCD) to [Ru(bpy)2Cl(BPEB)]+ leads to an inclusion complex, breaking down the aggregated array.
