Molecular wires Monomers

The group of Professor Nazario Martin developed the synthesis of several donor-acceptor arrays containing -conjugated oPPEs of different length linking -extended tetrathiafulvalene (exTTF) as electron donor and C o as electron acceptor. Thereby, they systematically increased the length of the molecular wire from the monomer to the trimer. A detailed description of the corresponding synthesis is described elsewhere [8]. 

In the second approach to self-assembly of polymer-silica nanocomposites, polymerizable surfactants are employed both to direct self-assembly into ordered mesophases and to serve as organic monomers which can be subsequently polymerized. For instance, Brinker et al. developed nonionic surfactants incorporating diacy-telene groups which could be polymerized upon irradiation by UV light.68 69 Similarly, poly(thiophene)70 and poly(pyrrole)71 have been successfully integrated into silica nanostructures in this manner. Importantly, this in situ polymerization produces isolated molecular wires, rather than clustered bundles of conductive polymer.70... 

The monomers (213), which were ultimately converted into novel conjugated polymers, have been prepared in poor yield by double Wittig reaction of the dialdehyde (212). Bis-Wittig reactions of l,3-propanebis(triphenylphos-phorane) (214) with ferrocenyl aldehydes (215) have been used to prepare a series of bis(ferrocenyl)polyenes (216) containing a central methylene group. These compounds were converted into the corresponding polymethine cations which are prototype molecular wires with redox-active end groups. 

Anderson et al. [34] reported the synthesis of conjugated polyrotaxanes encapsulated by cyclodextrin rings, as shown in Fig. 6. The hydrophobic diboronic acid monomer was encapsulated inside the cyclodextrin rings and polymerized by Suzuki coupling with a water-soluble diiodide monomer and terminated with bulky naphthalene stoppers to form the corresponding insulated molecular wires. 

Figure 19 Signal amplification produced from chemosensors wired in series. The method has been most thoroughly elaborated for signal transduction derived from a quenching process, (a) Luminescence quenching from individual monomer subunits upon molecular recognition, (b) Signal response from receptors wired in series. Only fractional occupancy is required to quench luminescence from polymer backbone. (Adapted from Ref. 6.)...

The polypheny1-as-triazines in this paper are relatively high molecular weight polymers containing 1,2,4-triazines and aromatic nuclei in the main polymer chains, h,, were between 1.39-2.16 dl/g ( 0.5% solution in cresol at 25c ) due to high purity of the two monomers concerned. A yellow, transparent, flexible film was prepared from each of these polymer solutions and varnished wire was obtained by coating the metallic wire... 

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