Construction And Characterization Of Metal Organic Supramolecular Nanoarchitecture Based On Pillar[5] Arene

As a novel class of supramolecular macrocyclic host,pillararene plays an important role in supramolecular chemistry due to their easy modification,highly symmetrical rigid structure and huge electron-rich cavities,which is widely used in biomedicine,multiple stimulus-response system,fluorescence sensor and other fields.On the other hand,triphenylamine derivative is a kind of chromophoric group with strong fluorescence and excellent hole-transporting capability,which is frequently employed in organic optoelectronic materials.In addition,photoinduced electron transfer?PET?system exists in nature as well as many scientific and technological fields,which is generally utilized in solar energy conversion,photocatalysis,organic photosynthesis,high-resolution imaging and other aspects.However,there are rare reports about the PET system based on pillararene,which needs to be further explored Based on this,a metal-organic supramolecular nanoarchitecture with PET system have been designd and synthesized in this thesis,which was assembled by Ru???bis-?terpyridine?-bridged pillar[5]arene?TPY-P5?Ru2+??dimmers and trizole triphenylamine amyl cyanide?TTAC?.Meanwhile,a series of properties and characterizations of supramolecular nanoarchitectures were investigated.More importantly,we further probed into the controllable adjustment of the system.The detailed contents are as following:1.Synthesis and characterization of host moleculeAs shown in Scheme 1,reaction between pillar[5]arene?5?and 4-?[2,2':6',2"-terpyridin]-4'-yl?phenol?6?afforded bis-?terpyridine?-bridged pillar[5]arene?7?,which reacted with Ru?DMSO?4C12 in EtOH and DMF solvent to generate host molecule Ru???bis-?terpyridine?-bridged pillar[5]arene?8?.The new compounds 7 and 8 were characterized by ¹H NMR?¹³C NMR and MALDI-TOF-MS analysis.2.Synthesis and characterization of guest moleculeAs shown in Scheme 2,tris?4-ethynylphenyl?amine?12?was synthesized from triphenylamine?9?in three steps.Afterwards,guest molecule trizole triphenylamine amyl cyanide?14?was prepared from tris?4-ethynylphenyl?amine?12?and 5-azidopentanenitrile?13?by click reaction.New compound 14 was characterized by ¹H NMR?¹³C NMR and HR-MS analysis.Its optical properties such as UV-vis absorption spectra and fluorescence spectra were also investigated.3.Construction and tunability of assemblyWe synthesized a metal-organic supramolecular nanoarchitecture with tunable PET system,which was assembled by host-guest noncovalent interaction between Ru???bis-?terpyridine?-bridged pillar[5]arene dimmers?host?and trizole triphenylamine amyl cyanide?guest??Scheme 3?.Firstly,we explored the self-assembly behavior between host and guest molecule.Subsequently,the morphology and size of the assembly was observed by SEM and TEM.In addition,the feasibility of electron transfer was theoretically verified by fluorescence quantum yield and density function theory?DFT?calculation.What's more,we probed into the controllable adjustment of the PET system:the increased polarity of solvent,the absence of pillar[5]arene and the introduction of competitive guest molecule adiponitrile?ADN?all can weaken the efficiency of electron transfer and adjust the fluorescence of the assembly.Finally,its UV-vis absorption spectra,aggregation-induced emission properties and fluorescence spectra were also investigated.