Viologen-based host–guest supramolecule with tunable intramolecular/intermolecular electron transfer chromism and dynamic fluorescence  

作　　者：Zhiang Bai Haotian Zhang Rui Xue Xilong Lu Xuyi Li Walker MacSwain Weiwei Zheng Jiaqiang Xu Yang Yu Yue-Ling Bai 

机构地区：[1]Department of Chemistry,College of Science,Shanghai University,Shanghai,P.R.China [2]Department of Chemistry,Syracuse University,Syracuse,New York,USA

出　　处：《Aggregate》2024年第5期340-348,共9页聚集体（英文）

基　　金：National Natural Science Foundation of China,Grant/Award Numbers:21571126,62271299;Shanghai Key Laboratory of High Temperature Superconductors。

摘　　要：Viologen,as a type of strong electron acceptor,is prone to undergo electron transfer(ET)and change color under external stimuli.However,due to the easy aggrega-tion of viologen molecules,they usually suffer from poorfluorescence emission in the condensed phase.Herein,a new viologen derivative of VioCl_(2)⋅2Cl(1^(2+)⋅2Cl)was designed and synthesized,in which thefluorescence was enhanced by intro-ducing Me-β-CD to weaken the interactions between viologen molecules.Then a viologen-based host-guest supramolecule of 1^(2+)@Me-β-CD was obtained by elec-trostatic interactions.Photo-/chemo-responded guest 1^(2+)supplies 1^(2+)@Me-β-CD,a green and dark purple caused by intramolecular and intermolecular ET.Further-more,1^(2+)@Me-β-CD displays an additional thermal responsive purple color.The triple chromic behaviors all exhibit excellent reversibility and cycling stability.As expected,1^(2+)@Me-β-CD exhibits strong photoluminescence(PL)in solid-liquid dual states,presenting an improved quantum yield(Φ)from 1^(2+)(Φ_(s)=0.37%,Φ_(1)= 16.74%)to=1^(2+)@Me-β-CD(Φ_(s)= 10.45%,Φ_(1)= 25.86%),and thefluores-=cence intensity can be dynamically modulated by light,heat,and acid/base vapors.The multi-responsive chromism and tunablefluorescence of 1^(2+)@Me-β-CD allow for potential applications in information security and smart windows.

关 键 词：chromism cyclodextrins dynamicfluorescence host–guest supramolecules VIOLOGENS 

分 类 号：O657.3[理学—分析化学]