Construction Of ?-Gels Based On Naphthalimides Functionalized Pillar[5]Arenes And Their Applications

Organogels derived from“?-gelators”are called“?-gels”which are soft,nonflowing materials derived from gelators with more than one aromatic?-unit.Due to its good properties and wide application value,?-gels has attraction extensive attention in the field of chemistry and materials science.Pillar[n]arenes,as a new type of macrocyclic host molecules,first reported in 2008.Pillar[n]arenes have attracted a lot of attention and have widely studied from scientists because of their unique rigid architecture,electron-rich cavities,facile functional modification,and could provide variety of supramolecular forces?such as?-?,C-H????interactions?and other advantages.The appearance of pillar[n]arenes has provided a new platform for the development of?-gels.But so far,there have few reports on pillar[5]arenes-based?-gels studies.In addition,naphthalimide groups could act as?-?interaction sites,hydrogen-bonding sites as well as fluorophore signal groups.Therefore,we design and synthesize a variety of naphthalimide-functionalized pillar[5]arenes?-gelators.This paper focuses on the study of naphthalimide functionalized-pillar[5]arene?-gels materials for the detection and separation properties of multi-guest.This paper is elaborated from the following four parts.In the first part,the origin and development of?-gels and its applications in different fields are introduced.On this basis,the research progress at home combined with abroad and the work basis of our groups,the research topic of this thesis is put forward.We design and synthesize variety of naphthalimide-functionalized pillar[5]arene?-gelators by reasonably to introduce the pillar[5]arene and naphthalimide groups into the?-gelators,and focuses on the study of?-gelators self-assembly into?-gels materials mechanism,and the application of these materials in multi-guest detection and separation.Inthesecondpart,wedesignedandsynthesizedabilateral N-?4-hydroxyphenyl?-naphthalimide functionalized-pillar[5]arene?-gelator BPN.The design strategies were as follows.First,the naphthalimide groups could act as?-?interaction sites,hydrogen-bonding sites,and fluorescent signal groups.Second,the pillar[5]arene groups could not only provide electron rich cavities that could tightly bind guest molecules but also act as?-?interaction sites.Interestingly,the supramolecular?-gelator BPN could assemble into a supramolecular polymer?-gel BPN-G.The BPN-G could selectively detect the aromatic acid isomers and separate them through the collaboration of?-?stacking interactions,hydrogen-bond interactions,and host-guest inclusion interactions.Therefore,this work provides a new idea for the identification and separation of isomers of organic compounds.Inthethirdpart,wedesignedandsynthesizedanaphthalimide functionalized-pillar[5]arene?-gelator AP5 and tripodal guest TA.The gelator AP5and TA could assemble to form a supramolecular polymer?-gel SHG through the?-?stacking,hydrogen bonds and host-guest inclusion interactions.Interestingly,the supramolecular polymer?-gel SHG shows spongy structure and strong aggregation induced emission?AIE?.Moreover,the SHG also exhibited multi-responsiveness toward outer stimuli such as heating-cooling,pH,competitive agents and mechanical action,which could facilitate its application as a smart material.More importantly,the xerogel of SHG shows separation properties for Fe³⁺,methyl orange,methylene blue and sudan I dyes.Simultaneously,the SHG could carry out ultrasensitive detection Fe³⁺?LOD is 0.9 nM?.This work provides a new method for designing and constructing multifunctional smart supramolecular polymer materials.In the fourth part,we designed and synthesized bis-naphthalimide functionalized-pillar[5]arene?-gelator?BPN?and bis-4,4'-dipyridyl guest?G?,and could self-assemble to form a spongy supramolecular polymer network?-gel SPN-TDPG by host-guest inclusion interactions.Interestingly,the SPN-TDPG shows detection and separation properties for broad spectrum pollutants,such as heavy metal ions,anions,oxometallates,various organic dyes,organic pollutants and volatile organic compounds?VOCs?.Moreover,the separation rates of SPN-TDPG-based xerogel for heavy metal ions,various organic dyes,organic pollutants and oxometallatescan reach up to 99.8%.The?-gel SPN-TDPG material has a good application prospect in the detection and separation of heavy metal ions,anions and organic pollutants.