We recently reported the preparation of tetraquaternary salts derived from 4,4'-bipyridine of the type (1; R = Me or Et, n = 2 ,3 or 4) [1], and showed that they were reversibly reduced to diradical dicat­ ions (2; R = Me or Et, n = 2, 3 or 4) by the uptake of two electrons. Reversible redox systems of this type are of interest as components of electrochromic memory display devices [2—5], as bi...

The title compound, {(C(10)H(10)N(2))[Cd(SO(4))(2)(C(10)H(8)N(2))(H(2)O)(2)]·2H(2)O}(n), consists of anionic chains of the Cd complex, diprotonated 4,4'-bipyridinium cations and uncoordinated water mol-ecules. In the anionic chain, the Cd atom lies on a center of inversion in an octa-hedral geometry. The midpoint of the coordinated bipyridine also resides on a center of inversion, as does the n...

Bipyridinium residues are amongst the most intensively studied building blocks in supramolecular chemistry. They have found widespread application in molecular systems that exhibit controlled switching, rotational motion and potential for data storage. Many of these complex nanosystems harness the controllable electrochemical properties of 4,4′-bipyridinium ions (“viologens”) in either their sy...

The past ten years have evidenced the rapid development of bipyridinium-based coordination polymers, however, the design and synthesis of photo-switchable luminescent materials with a non-destructive readout capability based on bipyridinium ligands are still at the primary stage. In this work, two new coordination polymers with a bipyridinium-functionalized m-benzenedicarboxyl ligand were synth...

The studies of geometrical structures, thermal stabilities, redox properties, nonlinear responses and optoelectronic properties have been carried out on a series of novel ferrocenyl (Fc) chromophores with the view of assessing their switchable and tailorable second order nonlinear optics (NLO). The use of a constant Fc donor and a 4,4'-bipyridinium acceptor and varied conjugated bridges makes i...

Tris-(N-phenylureido)-calix[6]arene derivatives are heteroditopic non-symmetric molecular hosts that can form pseudorotaxane complexes with 4,4'-bipyridinium-type guests. Owing to the unique structural features and recognition properties of the calix[6]arene wheel, these systems are of interest for the design and synthesis of novel molecular devices and machines. We envisaged that the incorpora...

The title compound, C(10)H(10)N(2) (2+)·C(8)Br(4)O(4) (2-)·2H(2)O, consists of a tetra-bromo-terephthalate dianion, a 4,4'-bipyridinium dication and two solvent water mol-ecules. Crystallographic inversion centers are situated at the center of the aromatic ring of the dianion as well as at the midpoint of the carbon-carbon bond connecting the pyridine rings in the dication. In the crystal, inte...

The movement of cucurbit[7]uril (CB[7]) driven by alpha-cyclodextrin (alpha-CD) is investigated by various experimental techniques including NMR, ESI-MS, UV-vis, and ITC. CB[7] can form stable pseudorotaxanes with N-methyl-N'-octyl-4,4'-bipyridinium (MVO2+) and N,N'-dioctyl-4,4'-bipyridinium (OV2+) dication in aqueous solution. CB[7] shuttles between the octyl and bipyridinium moieties in MVO2+...