7,7,8,8-tetracyanoquinodimethane 2 salt

The EPR spectrum of the tetracyanoquinodimethane salt of (10) has been measured (82JA1154). This material gave a g value of 2.0039 and a line width of 4 G. 

The above discussion indicates that nucleophilic organic radicals also induce the formation of arenediazenyl radicals. This was shown by Bespalov (1980) for the lithium salt of the tetracyanoquinodimethane anion radical (8.54). 

TCNQ-Polyphosphazene Systems. Tetracyanoquinodimethane (XX) salts crystallize in the form of stacked arrays that allow electrical semiconductivity (42). Although this phenomenon has been studied in many laboratories, it has not been possible to fabricate conductive films or wires from these substances because of the brittleness that is characteristic of organic single crystals. However, it seemed possible that, if the flexibility and ease of fabrication of many polyphosphazenes could be combined with the electrical properties of TCNQ, conducting polymers might be accessible. 

Although organic anion radicals are oxygen sensitive, they have been isolated as crystalline salts from a variety of electron acceptors (e.g., chloranil, tetracyanoethylene, tetracyanoquinodimethane, perylene, naphthalene, anthracene, tetraphenylethylene, etc.) and their structures have been established by X-ray crystallography.180... 

Several other organic systems have been stndied as potential electrochromes because of their redox behaviour. These include carbazoles, methoxybiphenyls, fluorenones, benzoquinones, naphthaquinones and anthraqninones, tetracyanoquinodimethane, tetrathiafnlvalene and pyrazolines. ° Of particnlar interest are the 1,4-phenylenedi-amines, which form highly colonred species on oxidation. These, known as Wurster s salts, exemplified by Wnrster s Bine (1.97), are anodically colouring and this type of material has found nse in composite electrochromic systems for car rearview mirrors (see 1.5.4.1). 

LeBlanc OH Jr (1965) On the electrical conductivities of tetracyanoquinodimethan anion-radical salts. J Chem Phys 42 4307 308... 

The electrical resistance of complex salts of the 2,4,6-triphenylthia-zinium cation and tetracyanoquinodimethane (TCNQ) has been measured. For one thiazinium cation and 2 mol of TCNQ, the specific resistances were found to be in the range of 5-15 fl/cm (82MI2). 

BDTT is one of the most powerful donors of the TTF class. Alkylthio-substitution, such as in BEDT-TTF (ET), leads to a slight reduction in its electron-donor capability. Nevertheless, salts of this cation radical with tetracyanoquinodimethane (TCNQ) and its... 

Key words 7,7,8,8-tetracyanoquinodimethane (TCNQ), methyl-TCNQ, anion-radical salts, IR absorption spectra, electron-phonon interaction, electric conductivity. 

Patent 1696428 USSR, subm. 4706057 prior, from June 15, 1989, regist. August 8. 1991 // Anion-radical salt of 2-methil-7,7,8,8-tetracyanoquinodimethane as an addend to organic conducting materials // V.A.Starodub, Ye.M.Gluzman, K.V.Krikunov et al. 

Since mainly the E° of the mediator dictates at what potential the heterogenous electron transfer occurs, the oxidation of NADH can now take place at a much lower potential. The different mediator structures used to produce CMEs for NADH oxidation at a decreased overpotential are summarized in Table I. As is seen in the table, not only chemically modified electrodes based on only immobilized redox mediators have been used for this purpose, but also electrodes based on the combination of redox mediators and NADH oxidizing enzymes (diaphorase and NADH dehydrogenase) as well as electrodes made of the conducting radical salts of tetrathiafulvalinium-7,7,8,8-tetracyanoquinodimethan (TTF-TCNQ) and W-methyl-phenazin-5-ium-7,7,8,8-tetracyanoquinodimethan (NMP-TCNQ). 

Conducting charge-transfer salts based on thienothiophene analogs of tetracyanoquinodimethane 91CSR355. 

Acetylcholineesterase and choline oxidase Carbon-fiber electrode having a recessed tip into which crystals of the conducting salts tetrathiafulva-lene—tetracyanoquinodimethane were galvanostatically deposited followed by AChE and ChO which were co-immobilized in the recess. No interference from uric acid. The electrode responded to 5 pM or 800 pM ACh within 4 s. Kinetic studies of the biosensor were reported. [22]... 

Conducting organic salt electrodes directly coupled to oxidases have been described such as, for example, A -methylphenazinium (NMP+) cation and tetracyanoquinodimethane (TCNQ-) anion as an electrode material for facilitating electron transfer of glucose oxidase47. Results with other salt cations, such as tetrathiafulvalene (TTF+) and quinoline (Q+), have been reported48. 

Charge-transfer complexes of dicyclopenteno 1,4,5,8-tetratellurafulvalene with a variety of donors such as tetracyanoquinodimethane were prepared7. By electrochemical oxidation cation radical salts with chloride, bromide, iodide, hexafluorophosphate, or hexaflu-oroarsenate as anions were obtained8. 

A1 1 charge-transfer complex was obtained when bis[9-telluraxanthenyl] and tetracyano-quinodimethane were combined in dimethylformamide or when bis[9-telluraxanthenyl] tetraiodide was reacted with the lithium salt of the anion radical of tetracyanoquinodimethane. ... 

J. Hubbard, Generalized wigner lattices in one dimension and some applications to tetracyanoquinodimethane (TCNQ) salts, Phys. Rev. 817 494—505 (1978). 

J. B. Torrance, The difference between metallic and insulating salts of tetracyanoquinodimethane (TCNQ) How to design an organic metal, Acc. Chem. Res. 12 79-86 (1979). 

L. R. Melby, Substituted quinodimethans VIII. Salts derived from the 7,7,8,8-tetracyanoquinodimethan anion-radical and benzologues of quaternary pyrazinium cations, Can J. Chem. 43 1448-1453 (1965). 

Tetracyanoquinodimethane (TCNQ) and many of its derivatives are easily reduced to anions of the type TCNQ-, which form salts with various cations. With many cations, e.g., tetrathiafulvalene cations (TTF+), and N-methyl phenazinium cations (NMP+), the TCNQ- anions form electronically conducting salts (- molecular metals, -> charge-transfer complexes) that can be used as electrodes, especially because of their electrocatalytic properties (- biosensors, -> electrocatalysis, -> molecular metals) [i,ii]. TCNQ undergoes insertion electrochemical reactions (-> insertion electrochemistry) leading to TCNQ salts [iii, iv]. Polymers... 

Tetrathiafulvalene electrodes — Tetrathiafulvalene (TTF) and many of its derivatives are easily oxidized to form cations of the type TTF+. With various anions, most prominent is the tetracyanoquinodimethane anion (TCNQ-), these cations form - charge-transfer complexes, i.e., salts with metal-like conductivities (- molecular metals). These salts are used in electrochemistry as electrodes or to modify the surface of electrodes, for the purpose of achieving desirable electrocatalytic properties (- electrocatalysis). Tetrathiafulvalene-substituted polystyrenes have also been synthesized and used as modified electrodes [ii]. 

V. Malatesta, R. Millini, and L. Montanari, Key intermediate product of oxidative degradation of photochromic spiro-oxazines. X-ray crystal structure and electron spin resonance analysis of its 7,7,8,8-tetracyanoquinodimethane ion-radical salt, J. Am. Chem. Soc., 117, 6258-6264 (1995). 

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