Synthesis And Properties Study Of Tetrathiafulvalene (TTF) Derivatives

Controlling the self-assembling ability and the self-organizing processes of single functional moieties (luminescent, semi-conducting, redox, etc.) into periodically ordered nanostructures by molecular engineering remains a great and fundamental challenge in materials science. This is all the more true because the various functions of single molecules can be considerably enhanced within ordered supramolecular assemblies. Intensive studies have focused on tetrathiafulvalene (TTF) for the preparation of conductive materials in bulk and thin film states due to its excellent electron-donating andπ-πstacked properties. Furthermore, TTFs are also very useful for sensors, molecular switches, NLO responses, OFETs or in the nanoscience area, especially with regard to molecular electronics. As a possible starting point in the search for new functional TTF derivatives, the various substituents were introduced to the periphery of the TTF or theπ-functional units were linked with TTFs through the spacers to synthesize three series TTF derivatives and studied their physicochemiscal properties.1,A series of TTF-dicyano-tetrathiacrown ether were synthesized through high-dilution technique. From TTF-dicyano-tetrathiacrown ether as precursors, under magnesium butoxide connected porphyrazine ring with four TTF units by a tetrathia-12-crown-6 ether linker to successfully obtain magnesium porphyrazine, metal-free porphyrazine and zinc porphyrazine. Their structures were characterized by 1H NMR,13C NMR, MALDL-TOF-MS and IR. Via cyclic voltammograms and UV, respectively, with alkali metal and some transition metal ions, we studied the complexing ability of some compounds. The UV/vis absorption behaviors of some compounds were studied and the results showed all the compounds synthesized in this part formed intramolecular charge transfer. The chain longer in spacer group for researched compounds can affect the functionality of intramolecular charge transfer. The self-assemble of target compounds in solid and liquid phase was studied and the films of some compounds were made by definite method. The feature and field effect properties of films were studied by AFM. These novel compounds were expected to become next generation advanced materials for ions channel and molecular wire. 2,The key maleonitrile 5 bearing two tetrathiafulvalene unit was prepared by cross-coupling reaction of 4,5-dicyano-1,3-dithiol-2-one with 4,5-bis(dodecylthio)-1,3-dithiol-2-thione. A Mg(Ⅱ) template cyclization of the precursor with excess phthalonitrile gave the unsymmetrical Magnesium porphyrazine. All intermediates and target compound were fully characterized using spectroscopic data. Target compound was soluble in common organic solvents such as CHCl3, CH2Cl2, benzene, toluene, THF, DMF and DMSO. The solution electrochemical data of target compound showed two reductive and three oxidative processes within a-2V to+2V potential window, the five couples observed were assigned to Pz-3/Pz-4 (Ⅰ), Pz-2/Pz-3 (Ⅱ), TTF+/TTF (Ⅲ), TTF+2/TTF+(Ⅳ) and Pz-1/Pz-2 (Ⅴ). The electronic absorption spectra of it at different concentrations in different solvents showed that it is aggregated to form trimer in the CH2CI2, but it was essentially free from aggregation in THF. The dual component gelatin of target compound was obtained by added (1R,2R)-trans-bis(dodecanoylamino)-cyclohexaneand and the feature of gelatin was observed by SEM.3,A series of novel glassy liquid crystals based on a tetrathiafulvalene and cholesteryls were synthesized through couping reaction of 4,5-bis(cholesteryloxycarbonylalkylthio)-1,3-dithiole-2-one and their phase sequences and phase structures were investigated based on data of DSC, POM and XRD. The compounds having shorter spacer (n=2-5) exhibited a wide temperature range of smetic A phase and that of longer spacer (n=7) exhibited a wide temperature range of hexaganal columnar phase, no crystallization but vitrifying to form glassy mesogens during cooling from the isotropic melt. The molecular parking in this series are closely related to the length of spacers. In order to evaluate electrochemical properties, the cyclic voltammetry (CV) measurements were performed in a dry Dichloromethane solution. Target compounds showed two reversible single-electron oxidation peaks, corresponding to the formation of radical cations and dications, respectively, indicating two sequential reversible one-electron transfer steps. The oxidation potentials of these compounds are higher than those of TMT-TTF analogue probably due to the existence of electron-withdrawing ester linkages in the distance. Therefore, the oxidation potential decreased as the length of spacers n increased for n<3, but changed slowly after n=3.