Oh crystallography
Sometimes nature has a sense of humor, too:
http://pubs.acs.org/doi/abs/10.1021/ic0352250
I don't know if people not on university internet can read it, but here's the abstract of a paper published in 2004:
Article
{trans-1,4-Bis[(4-pyridyl)ethenyl]benzene}(2,2‘-bipyridine)ruthenium(II) Complexes and Their Supramolecular Assemblies with β-Cyclodextrin
Sergio H. Toma,† Miriam Uemi,† Sofia Nikolaou,† Daniela M. Tomazela,‡ Marcos N. Eberlin,‡ and Henrique E. Toma*†
Instituto de Qumica, Universidade de So Paulo USP, Caixa Postal 26077, CEP 05513, So Paulo, SP, Brazil, and Instituto de Qumica, Universidade Estadual de Campinas, Campinas, SP, Brazil
Abstract
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.
http://pubs.acs.org/doi/abs/10.1021/ic0352250
I don't know if people not on university internet can read it, but here's the abstract of a paper published in 2004:
Article
{trans-1,4-Bis[(4-pyridyl)ethenyl]benzene}(2,2‘-bipyridine)ruthenium(II) Complexes and Their Supramolecular Assemblies with β-Cyclodextrin
Sergio H. Toma,† Miriam Uemi,† Sofia Nikolaou,† Daniela M. Tomazela,‡ Marcos N. Eberlin,‡ and Henrique E. Toma*†
Instituto de Qumica, Universidade de So Paulo USP, Caixa Postal 26077, CEP 05513, So Paulo, SP, Brazil, and Instituto de Qumica, Universidade Estadual de Campinas, Campinas, SP, Brazil
Abstract
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.