Tetrathia fulvalenes

Eullerene-based donor-acceptor complexes and ion-radical salts with tetrathia-fulvalenes, metalloporphyrins, and cyclic amines as donors 99UK23. 

Providing an ion exchanger with a sufficient number of redox groups so that conduction can occur by a relay-type redox-change mechanism. Examples are hydroquinone-derived redox polymers and polyvinyl polymers with a tetrathia-fulvalene, ferrocene, or carbazole group, which have been found useful for research and analytical applications. 

Yamada J, Sugimoto T (2004) TTF chemistry fundamentals and applications of tetrathia-fulvalene. Springer, Berlin Heidelberg New York... 

Redox molecules are particularly interesting for an electrochemical approach, because they offer addressable (functional) energy states in an electrochemically accessible potential window, which can be tuned upon polarization between oxidized and reduced states. The difference in the junction conductance of the oxidized and the reduced forms of redox molecules may span several orders of magnitude. Examples of functional molecules used in these studies include porphyrins [31,153], viologens [33, 34,110,114,154,155], aniline and thiophene oligomers [113, 146, 156, 157], metal-organic terpyridine complexes [46, 158-163], carotenes [164], nitro derivatives of OPE (OPV) [165, 166], ferrocene [150, 167, 168], perylene tetracarboxylic bisimide [141, 169, 170], tetrathia-fulvalenes [155], fullerene derivatives [171], redox-active proteins [109, 172-174], and hydroxyquinones [175]. 

An example of a system that can be switched reversibly in three different states through electrochemical control of the guest properties of one component is illustrated in Figure 10.1281 Tetrathia-fulvalene is stable in three different oxidation states, TTF(0), TTF+, and TTF2+. On oxidation, the electron-donor power of tetrathiafulvalene decreases with a... 

Le Narvor N, Robertson N, Weyland T, Kilbum JD, Underhill AE, Webster M, Svenstrup N, Becher J (1996) Synthesis, structure and properties of nickel complexes of 4,5-tetrathia-fulvalene dithiolates high conductivity in neutral dithiolate complexes. Chem Commun 1363-1364... 

Horiuchi S, Yamochi H, Saito G, Sakaguchi K, Kusunoki M (1996) Nature and origin of stable metallic state in organic charge-transfer complexes of bis(ethylenedioxy)tetrathia-fulvalene. J Am Chem Soc 118 8604—8622... 

J. B. Torrance, A. Girlando, J. J. Mayerle, J. I. Crowley, V. Y. Lee, P. Batail, and S. J. LaPlaca, Anomalous nature of neutral-to-ionic phase transition in tetrathia-fulvalene-Chloranil, Phys. Rev. Lett. 47 1747-1750 (1981). 

After the discovery of the interesting electrical properties of tetrathia-fulvalene (TTF)-tetracyanoquinodimethane (TCNQ) complexes, many TTF derivatives have been prepared by reaction of 1,3-dithiolium salts with tertiary amines. This reaction has been interpreted as proceding by deprotonation of a 1,3-dithiolium cation to the corresponding carbene which in turn reacts as a nucleophile on the C-2 of another 1,3-dithiolium cation. This topic having been recently reviewed, we refer in Table 309,310 Qjjjy jQ papers subsequent to this review. ... 

Fluoride ion-induced formation of bis- and tetrakis(vinylthio)tetrathia-fulvalenes has been reported when 1,2-dibromoethane is used as the alkylating agent or when an ethylenedithio bridge is present in the starting material (91TL2737). 

Tetraselenafulvalene (TSF) can be lithiated, although the scope of this reaction is more restricted than in the case of TTF (Section III.B). Only a few substituents have been introduced into the TSF core to date, and their reactions, which are quite similar to those of the analogous tetrathia-fulvalenes, are discussed in Section III.C. 

The most efficient organic conductor material consists of co-crystals of tetracyano-Jt-quinodimethane, an electron-poor quinone analog, and tetrathia-fulvalen, an extremely potent electron donor. The crystals are green and have a conductivity of o = 1.5 x 10 Siemens cm Vat 66 K as compared to metallic copper with a a = 6 x 10 Siemens cm at 298 K. In order to obtain such high conductivity, organic charge transfer complexes must not appear as face-to-face dimers in crystals. In such cases, the acceptor takes up an electron and... 

Synthesis and applications of tetrathiafulvalenes and ferrocene-tetrathia-fulvalenes and related compounds as electroactive organic materials 05T3889. 

There is a myriad of examples in the literature where UV-vis titrations are used to determine binding constants in 1 1 equilibria systems. For a recent example, see for instance, the work of Sessler and coworkers on a tetrathia-fulvalene diindolylquinoxaline receptor that binds to anions such as dihydrogen phosphate (Figure 3). ... 

For more than 20 years, electrical conduction in organic solids has been one of the most fascinating topics for organic chemists and solid-state physicists. This considerable interest was triggered by the discovery of high electrical conductivity in molecular crystals of tetrathia-fulvalene-tetracyanoquinodimethane (TTF-TCNQ) in 1973 [1] and in the oxidized form of a 7r-conjugated polymer, namely polyacetylene, a few years later [2]. 

Complexation with other donor organic molecules such as ferrocene [75] (Figures 1.12 and 1.13), Fe4(CO)4(> -C5H5)4 [76], hexamethylenetetratelurafiil-valene (HMTTeF) [77], bis(ethylenedithio)tetrathia-fulvalene (BEDT-TTF) (Figures 1.14 and 1.15) [78] or the dimer of BEDT-TTF [79] gave insulating, neutral CT complexes in which Ceo co-crystallizes with the donor unit. Recently, other complexes with tellurium donor derivatives have also been reported [80]. 

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