Synthesis And Self-assembly Studies Of Triazine-linked Porphyrin-oxadiazole-glycine

The most efficient process to use solar energy in nature is photosynthesis. Andthe photosynthetic reaction center has been the focus of artificial photosynthesis thatconsists of many aggregates self-assembled by18-π electron conjugated macrocyclicporphyrins. Therefore, research on self-assembly methods to prepare porphyrin hasbeen a hotspot. Self-assembly technology is a way that small units are assembled torelative large structure spontaneously via weak interactions such as hydrophobicinteraction, hydrogen bonding, packing effect, electrostatic interaction, etc.Amazingly, the size of self-assembled porphyrins can achieve nanoscale. It is wellknown that nanomaterials have special surface effects, small size and macroscopicquantum tunneling effect, performing many surprising properties. And the porphyrinspossess inherently excellent photophysical and photochemical properties.Consequently, with the two aspects above, porphyrin nanoscale materials are expectedto show physical and chemical properties superior to the traditional materials ofporphyrin, and applied to the molecular switches, molecular sensors, storage devices,and other fields.We optimize the synthenic route of Triazine-linkedPorphyrin-Oxadiazole-Glycine (ATPP-OXA-G). The structure was confirmed byFTIR,1H NMR and MALDI-TOF-MASS.For ATPP-OXA, the uv-visible spectra show that the interaction betweenporphyrin moiety and oxadiazole moiety was very weak in the ground-state. Resultsobtained from the cyclic voltammetry, steady-state fluorescence and fluorescencelifetime indicate that photoinduced electron transfer from the excited porphyrinmoiety to oxadiazole moiety was very weak. When the wavelength was315nm,energy transfer from oxadiazole moiety to porphyrin moiety and electron transferfrom porphyrin moiety to oxadiazole moiety occurred.Carboxyl group plays an important role in photophysical properties ofATPP-OXA-G:（1）the groud state function was affected （2）the whole compoundexhibits the property of ATPP, not DATPP, indicating that interaction betweenthe bridge linker and porphyrin moiety is changed by carboxyl group （3）the formation of charges-separated state was enhanced by carboxyl group.Additionally,sphere ATPP-OXA-G nanoparticles were obtained via an surfactant-assistedself-assembly(SAS) method by addition dropwise of ATPP-OXA-G in polar solventDMF into an aqueous solution of surfactant cetyltrimethylammoniumbromide(CTAB). Steady-state absorption and fluorescence, time-resolvedfluorescence spectroscopy were employed to find the difference betweenATPP-OXA-G monomer and ATPP-OXA-G nanostructure.