Research In The Construction And Application Of Supramolecular Fluorescent Assemblies Based On Functionalized Pillararene

As one of the core contents of supramolecular chemistry research,host-guest recognition refers to the process that host molecules selectively recognize a guest molecule and produce specific functions under the non-covalent interaction.As the fifth generation of macrocyclic host molecules,pillararene is favored by chemists because of their special rigid architectures,flexible modification,simple synthesis,and excellent host-guest properties.In recent years,the supramolecular fluorescent assembly based on the host-guest recognition of pillararene has a wide range of applications in biomedicine,optoelectronic materials,smart materials and other fields.In this work,pillar[5]arene was acted as the framework,taking advantage of cavity size and electron-rich properties of pillar[5]arene to selectively bond guest molecules,and then construct a new supramolecular fluorescent assembly to study its application in multi-color fluorescent materials and formaldehyde detection.The details are as follows:（1）Firstly,the development of supramolecular host-guest chemistry,the basic properties,synthesis methods,derivatization stategies,host-guest properties and application of pillararene in supramolecular luminescent materials are reviewed.（2）The pillararene-rare-earth-assembly with red/green fluorescence emission was constructed by the coordination of pillar[5]arene modified with tripyridine derivatives and rare earth ions Eu³⁺/Tb³⁺.This assembly can regulate the color change of the assembly by adjusting the ratio of column aromatics,Eu³⁺,Tb³⁺.With the introduction of polymer guest structure,the assembly has good gel properties and self-healing properties.We also investigated the fluorescence"on off"response behavior of the assembly under acid-base vapor stimulation.（3）A thin film sensor was prepared by the supramolecular assembly of hydrazinonaphthalimide functionalized pillar[5]arene and polymer chains modified with guest units,and the detection behavior of the sensor for formaldehyde was investigated.The electron rich cavity of the pillararene makes the assembly more sensitive to the detection of formaldehyde.Not only does the assembly of the cavity and the polymer guest give the assembly a certain gel performance.The thin film sensor prepared based on assembly method has sensitive detection behavior for gaseous formaldehyde,and also has good performance in detecting samples in daily life.