Synthesis And Properties Study Of Tetrathiafulvalene (TTF)-Annulated Tetraazaporphyrin Derivatives

Exploitation and research of functional molecules and supramolecular materials with optical, electrical, ionic, magnetic, thermal, mechanical and chemical properties has been hot spots in the current field of synthetic organic chemistry and physical chemistry. Like porphyrins and phthalocyanine, porphyrazines has a big ring with tightly fused molecular skeleton and a conjugatedπelectron delocalization systems and implied chromophoric properties, high thermal stability, sublimability, acid-resistant, base-resistant and excellent electronic properties etc., they have more and more attracted considerable attention in many field. 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.If the strong electron donor TTF-modified porphyrazines can be synthesized and get the donor-porphyrazines diad system, it is very significative. Electronic transfer of the system from TTF to porphyrazines nuclear is expected and bear other specific functions, but these compounds are very few reported yet. Our working group had synthesized the first TTF-annulated tetrazaporphyrin derivatives, We had reported the synthesis of novel porphyrazines (Pzs) annulated with four TTF units that also contain electron-donating alkylthio groups. These molecules spontaneously form TTF group radical cations during the separation process. This hindered an accurate assessment of their photophysical and electrochemical properties.In order to reduce electron-donating capability of TTF units, we introduced the appropriate withdrawing electron groups in 6,7 position of TTF units and reduced the TTF-annulated amounts. We had synthesized seven symmetry molecules in merging the number of units was synthesized by means of the novel symmetry porphyrazines (Pzs) annulated with four TTF units that contain electron-withdrawing alkoxy carbonyl groups and three asymmetrical porphyrazines annulated with one TTF units that contain hydrophilic group. Because the target compounds is very stable on the heat, the air, so their physical and chemical properties are well studied. As expected, the TTF annulated Pz dyes were sufficiently stable for purification, so that their photophysical and electrochemical properties have been well studied. 1. Seven novel tetrathiafulvalene-annulated metalloporphyrazines with electron-withdrawing alkoxy carbonyl groups at the periphery were synthesized via the cyclotetramerization of dipentyl 6,7-dicyanotetrathiafulvalen-2,3-dicarboxylate in the presence of corresponding metal salts (Zn(OAc)2-2H2O, Cu(OAc)2·2H2O, and NiCl2) and in alcohol (pentanol, dodecanol and octadecanol). Molecular structures were fully characterized by 1H NMR, 13C NMR, FT-IR, UV-vis, MALDI-TOF mass spectra and elemental analysis. These newly synthesized macrocyclic dyes were sufficiently stable in air during the purification process and also in further experiments. Electron-withdrawing substituents reduced the ability of tetrathiafulvalene groups to form radical cations. Solution electrochemical data showed one reductive and three oxidative processes within a-2000 mV to+2200 mV potential window. The four couples observed were assigned to Pz-2/Pz-3 (Ⅰ), TTF/TTF (Ⅱ), TTF+2/TTF (Ⅲ) and Pz-1/Pz 2 (IV). Electronic absorption spectra of the compounds show the characteristic absorption peak of tetraazaporphyrin derivatives in the Q band and B band. The position of absorption peak affected by the metal ions on the tetraazaporphyrin nuclear center and has nothing to do with the length of flexible chain. Moreover, it is approved formation of F4TCNQ/TTF charge-transfer complex with doping 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) in target compounds by UV-Vis, FT-IR and ESR.The dual component gelatin of tetrathiafulvalene-annulated metalloporphyrazines with electron-withdrawing long chain alkoxy carbonyl (dodecyl and octadecyl) groups at the periphery was obtained by added (1R,2R)-trans-Bis(dodecanoyl-amino)-cyclo-hexane and the SEM image shows a three-dimensional spongelike structure with average sheet thickness of 5μm. We investigated self-assembly of the target compounds in the solid and liquid and obtained membrane of a few compound through a certain way and observed the AFM morphology of the film. These novel compounds were expected to become next generation advanced materials for ions channel and molecular wire.At last, frontier orbital energy levels of four model compounds [TTF-Pzs-M] (M=Mg, Zn, Cu, Ni) is calculated By SAOP/TZP and obtain their absorption spectra in the gas phase and chloroform solution by fitting. These recults match well with the experimentally measured absorption spectra.2. The precursor dicyano-tetrathiafulvalene derivative was prepared by cross-coupling reaction of 4,5-dicyano-1,3-dithiol-2-one with 4,5-bis(2,5,8,11-tetraoxatridecylthio)-1,3-dithiol-2-thione through high-dilution technique. A Mg(Ⅱ) template cyclization of the precursor with excess 2,3-bis(methylthio)maleonitrile gave the unsymmetrical Magnesium porphyrazine, which was easily converted to metal-free porphyrazine by treatment with acetic acid in the dark. Upon the action of zinc acetate, the metal-free porphyrazine was converted to Zinc porphyrazine. The new products were fully characterized using spectroscopic data and elemental analysis. They were soluble in common organic solvents such as CHCl3, CH2Cl2, benzene, toluene, AcOH, THF, DMF and DMSO. Solution electrochemical, UV-Vis and ESR data revealed that all porphyrazines showed better electron-donating properties and can form an electron transfer complex with 7,7,8,8-tetracyanoquinodimethan(TCNQ) and F4TCNQ. In addition, complexation behavior of the precursor compounds and target compounds with the metal ions Ag+, Pb2+ had been studied by UV-Vis spectrum.