Electrochemical recognition cations

Electrochemical recognition of cationic guest species by redox-active... 

Electrochemical recognition, 39 80 anions, macrocyclic and acyclic polycobalti-cinium ligand systems, 39 134-140 cations, 39 81-133 ammonium cation, 39 128-133 crown ether and bis crow ether ligands containing bipyridyl transition metal recognition sites, 39 111 crown ether dithiocarbamate and dithi-olene complexes, 39 123-124 di-h-cyclopentadienyl-molybdenum(IV) and -tungsten(IV) crown ether complexes, 39 107-108... 

Electrochemical recognition experiments with Co(Et2NCS2)3 revealed no evidence of interactions with Group I metal cations. 

Beer, P. D. Gale, P. A. Chen. G. Z. Mechanisms of electrochemical recognition of cations, anions and neutral guest species by redox-active receptor molecules, Coord. Chem. Rev. 1999, 185-186, 3-36. 

D. Electrochemical Recognition of Transition Metal Guest Cations by Ferrocene Aza-, Thia-Donor Macrocyclic Ligands... 

Although Becher, Underhill, and co-workers (36—48) have prepared a number of macrocycles containing the tetrathiafulvalene redox center (Scheme 3) primarily designed to coordinate transition metal cations, no electrochemical recognition studies have as yet been reported. A tetrathiafulvalene-tetrasubstituted benzo-15-crown-5 ionophore (5) has... 

Novel heterotrinuclear complexes ((64), (65)) have also been described by the same group (107), although no electrochemical recognition studies of Group IA, IIA guest cations are reported. 

The nature of the solvent can also have a profound effect on the electrochemical recognition process. All of the redox-responsive ligand systems cited in this review give examples of guest cation/anion redox couple perturbations in organic solvents such as dichloromethane and acetonitile. The next challenge will be to demonstrate analogous redox-responsive behavior in the aqueous environment. 

Supramolecules containing metal-polypyridine units, especially the Ru(dpp)-based dendrimers, could be used as electron reservoirs or components of molecular-electronic devices. Supramolecules in which an electroactive M(N,N) group is attached to a receptor capable of molecular recognition (crown ethers, calixarenes, cryptands etc.) can work as electrochemical sensors. Electrochemical recognition of cations as well as anions has been reported [33-35, 257, 263]. 

Smith, D.K. Spencer, P. Transition metal cation and phosphate anion electrochemical recognition in water by new polyaza ferrocene macrocyclic ligands. Inorg. Chim. 35. Acta 1996, 246, 143. 

Nevertheless, as the cyclic voltammograms were stabilized only after a very large number of scans, poty(13a) was not suitable for the electrochemical recognition of cations in real time. 

Such an increase in the oxidation potential of the polymer upon the complexation effect could be interpreted as a consequence of the deviation from coplanarity of the polypyrrole chain. This explanation was supported by the results obtained with polypyrrole N-substituted with a benzo-15-crown-5 unit which did not show any electrochemical recognition property toward alkali cations [269]. 

Abstract. The synthesis, metal, ammonium and alkyl ammonium cation coordination chemistry and electrochemical recognition studies of new diester- and diamide-calix[4]arenediquinone receptors are described. In addition the synthesis and coordination properties of a novel diamide benzo-15-crown-5-calix[4]arene molecule is reported. 

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