Functionalization Of Hydroxyquinoline-diarylethene Molecules And Study On Fluorescence Sensor Properties

In recent years,fluorescence sensors have significant potential applications in chemistry,biology,medical analysis,environmental monitoring and bioluminescence imaging.Compared with others fluorescence sensors,the fluorescence sensors based on diarylethene molecule captured much attention of many researches.Diarylethene molecules were known as the most promising photochromic materials because of their special structures,which could undergo two reversible isomers under the irradiation with UV and visible light as well as good thermal stability,fatigue resistance and rapid reactivity.Therefore,with the acid/base effects,ions,amino acids and other specific recognition of diarylethene molecules were the trend of the currently studying.In general,the most basic methods were combined the functional groups and diarylethene to design and synthesis of new diarylethene fluorescence sensors.On this basis,six novel diarylethene molecules were designed and synthesized.First,the hydroxyquinoline-diarylethene molecules were synthesized by the reaction of hydroxy groups on the hydroxyquinolines and the methylene bromide of the diarylethene.Then,the functional groups were used to achieve the desired results.The photochemical properties of the six compounds and the responsiveness of the ionic amino acids were systematically investigated.The main research contents as follows:In chapter 1,the research background about the current research status of diarylethene compounds and its applications in chemical and biological fields,as well as the literatures of some quinolone and its derivatives applied in fluorescence sensors were reviewed.Then,the target of our research was proposed by studying its photochemical properties.In chapter 2,two benzothiazole,benzimidazole functionalized diarylethene molecules were designed and synthesized.DTE-1 and DTE-2 exhibited significant photochromic and fluorescence switching properties in tetrahydrofuran.DTE-1 could sequential recognize Hg²⁺and Cys?cysteine?.DTE-1 itself displayed a strong fluorescence,the fluorescence quenched by the addition of Hg²⁺.Then,the Cys was continued added into the solution of DTE-1,its fluorescence intensity could be basically restore to the fluorescence intensity of DTE-1.DTE-2 could recognize Zn²⁺and Cd²⁺in different coordination modes.In chapter 3,two kinds of diarylethene functionalized by rhodamine were designed and synthesized.The photochromic processes,ion-selective and acid/base effects of these two materials were studied.When DTE-3 and DTE-4 were in the presence of trivalent ions(Fe³⁺,Cr³⁺,Al³⁺)or acid,the lactone form?closed?were changed to carboxylate form?opened?and their fluorescence intensity were enhanced obviously.The only difference was that DTE-3 without time-dependence,while DTE-4 would take a long time?more than 2 hours?to recognize the ions.In chapter 4,two kinds of diarylethene molecules modified by functionalized hydrazide were designed and synthesized.DTE-5 and DTE-6 could be quenched by I^-with their own displayed fluorescence.Photochromic and fluorescence switching properties were also disscussed.