Tetrathiafulvalene derivative

Synthesis of tetrathiafulvalene derivatives for the creation of new organic functional materials 98YGK755. 

A C60 derivative with an attached fluorinated chain gave a limiting area of 0.78 nm molecule [266]. It was reported that this film was so mechanically rigid that it pushed the Wilhehny plate out of the water at 11 14 mN m The monolayer spreading of this compound arises from the even greater hydrophobicity of the fluorocarbon chains and their orientation away from the water surface. The LB films with a fluorinated tetrathiafulvalene derivative did not show evidence of charge transfer in their UV spectra. 

Adduct between Cgg fullerene and a tetrathiafulvalene derivative gives rise to ion-radicals with a very distinct difference between products of one-electron attachment and removal. This difference... 

Fe(C204)3] anions with associated water and PhCN. The tetrathiafulvalene derivatives (ttf)7[Fe(C204)3]2 4H20 and (ttf)5[Fe(C204)3] 2C6H5Me 2H20 are semiconductors with stacked structures. 

CV investigations of 6-mercaptopurine and 8-mercaptoquinoline SAMs on pc-Au electrodes have been presented by Madueno et al. [186] and He etal. [187], respectively. Several model electrode reactions involving various redox probes were studied using such modified electrodes. Baunach and Kolb etal. [188] have deposited copper on disordered benzyl mercaptan film on Au(lll) surfaces. They have also studied the behavior of benzyl mercaptan SAM on Au(lll) in H2SO4 solution using CV and STM. Structural and electrical properties of SAMs based on tetrathiafulvalene derivatives on Au(lll) were investigated. These mono-layers were disordered, or at least loosely... 

Tetrathiafulvalene derivatives undergo reaction with nucleophiles, such as 195, to produce the linearly-fused TTF compounds such as 51 in reasonable yields (Equation 130). A small amount of the angularly substituted regioisomer is... 

Upon the first reduction, the voltammetric wave shifts by 20-30 mV, presumably due to donor-acceptor interactions resulting from the naphthalene and cyclophane moieties.39 The second reduction remains relatively unaffected, indicating that the complex disassembles prior to the second reduction of the cyclophane. Alternatively, the complex can disassemble through competitive binding interactions with a tetrathiafulvalene derivative. Thus, Cooke and coworkers demonstrate that self-assembly at exo-active surfaces can be reversibly controlled via an external electrochemical stimulus or competitive binding interactions. 

A recent attempt to prepare the bis(ethylenedithio)tetrathiafulvalene derivatives fused with a 1,4-dioxane ring, viz. (89), by the Me Al-promoted reaction of organotin thiolate (87) with ester (88) was unsuccessful instead the reaction resulted110 in the production... 

Fig. 6-1 Examples of soluble and fully conjugated oPPV molecular wires covalently connected to a C60 electron acceptor and an extended tetrathiafulvalene derivative (exTTF) electron donor (C/sn-oWV-exTTF). These triads exhibit wire-like behavior and electron transfer over distances of 40 A and beyond...

Polymeric tetrathiafulvalene derivatives show a more complicated behaviour (Table 9). Up to 0.4 mole (I) per monomer unit, poly-1 -(p-phenylene)-2,3-dimethyltetrathiafulvalene 19, R = Me, gives spectra consistent with the presence of I3 , but at one atom of iodine per monomer and above, the spectra change. Three subspectra are seen, with parameters close to those ofI5", but the intensity ratios are not the expected 2 2 1. The data of Table 9 show that two of the subspectra for I5 are unresolvable from the two sets found for I3 ... 

On the other hand, it has been shown (79ZC192) that photolysis of benzo- and aryl-substituted 1,3-dithiolethiones (23) produced the tetrathiafulvalene derivatives of type (24). 

Benzyne also reacts with carbon disulfide to produce the tetrathiafulvalene derivative (300) (75S38, 74CC166). Dithioacids react with phenylacetylene to form 1,3-dithioles (301) (80TL2247). 

A convenient preparation of tetrathiafulvalenes is achieved by the reduction of 2-methylthio-l,3-dithiolylium salts (207) with zinc dust in the presence of bromine (76ZC317). This reaction proceeds with formation of the radical (341) which dimerizes to (342) the latter produces dimethyl disulfide and the tetrathiafulvalene derivatives (343). 

Electrochemical reduction of the 2-ethylthio-l,3-dithiolylium salts (344) in acetonitrile gives the corresponding dimers (345) which can then pyrolyze to the tetrathiafulvalene derivatives (24) in nearly quantitative yields (74JA945). When one considers the total yield, this method is superior to the base-catalyzed dimerization of 1,3-dithiolylium ions. However, for large-scale synthesis, the convenience may be questionable. 

Dithiolylium salts react with the phosphoranes (349) in the presence of excess triethylamine to produce the tetrathiafulvalenes (351) (78JOC369). The primary step is formation of the coupling product (350) then triethylamine induces elimination of triphenylphosphine. This method allows the preparation of tetrathiafulvalene derivatives from two differently substituted 1,3-dithiolylium cations. 

Further progress was achieved with the subsequent synthesis of the bis(2-oxypropylenedithio)tetrathiafulvalene-containing [2]-rotaxane 33. An electron-rich tetrathiafulvalene derivative appeared an attractive candidate for incorporation into the linear component. The parent tetrathiafulvalene is of comparable bulk to a hydroquinone group and has also been demonstrated to exhibit reversible redox behaviour at low potentials. Further, the green 1 1 complex between tetrathiafulvalene and the above cyclophane tetracation had been characterised previously -... 

The discovery of the unusually high solid-state electrical conductivity of the charge-transfer complex of TTF with TCNQ has prompted extensive investigations of 1,3-dithiolium salts, an important class of intermediates for the synthesis of tetrathiafulvalene derivatives. 

Tetrathiafulvalene Derivatives Prepared bv Deprotonation of 1,3-Dithiolium Salts"... 

Well-known1 Cr111 A-thiocyanate complexes, such as [Cr(NCS)(,]3-, [Cr(NCS)4 (M I3)2] (Rein-ecke anion), and their derivatives, are currently extensively used for the syntheses of charge-transfer salts of organic donors (tetrathiafulvalene derivatives) aimed towards the development of... 

Tetrathiafulvalene Derivatives and Related Organic Materials. - Wittig-type reactions and reagents continue to play an important role in this burgeoning field of research. Some examples of the types of compounds being prepared using these routes are illustrated here. 

New trends in the synthesis of tetraselenafulvalene and tetrathiafulvalene derivatives as 7i-electron donors for molecular conductors and superconductors 04CRV5057. 

Tetraselenafulvalene and tetrathiafulvalene derivatives as organic conductors with unusual band fillings 04CRV4947. 

Tetraselenafulvalene and tetrathiafulvalene derivatives in conducting organic radical cation salts with organic and organometallic anions 04CRV5203. 

Tetrathiafulvalene derivatives in conducting and magnetic Langmuir Blodgett films 04CRV5479. 

Tetrathiafulvalene Derivatives Prepared by Deprotonation of 1,3-Dithiouum Salts"... 

Some typical reactions of 1,1 -difluoroethene with nucleophiles are summarized in Scheme 2.18. Alkoxides [3], trialkylsilyl anion [4], ester enolates [5], and diphenylphosphinyl anion [6] attack the gem-difluorinated carbon of 5. However, it is noteworthy that nucleophilic substitution and proton abstraction are in some cases competitive, and thus s -butyl lithium abstracts the (3 -vinylic proton predominantly to generate vinyllithium. The lithium species can be trapped with an aldehyde, providing difluoroallyl alcohol, which is then hydrolyzed to a, (3-unsaturated carboxylic ester (11) [ 7 ] (Scheme 2.19). Some synthetically useful examples are shown in Schemes 2.20 and 2.21. Tetrathiafulvalene derivative (14) is prepared from difluorinated derivative (13) [8]. An elegant intramolecular version was demonstrated by Ichikawa, which provided a range of cyclized compounds (17), including dihydrofurans, thiophenes, pyrroles, and cyclopentenes, and also corresponding benzo derivatives (20) [2]. 

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