The Studies Of The Synthesis And Properties Of Fluorescent Chemosensors Based On Fluorescein-diarylethene

Chemosensors have attracted great interest for their functional studies.Fluorescence chemosensor has gained a lot of interest for it use fluorescent as the output signal.Compared with other chemical sensors,fluorescence chemosensor have been widely focused for their convenient,high sensitivity and rapid response.for metal ions.Fluorescence chemosensor has a significant potential foreground in food analysis,process control,environmental monitoring,bioluminescence imaging,and medical diagnosis.Diarylethenes are one of the most promising candidates for practical applications because of their remarkable fatigue resistance,excellent thermal stability,and excellent molecular switch performance.Therefore,we could combine the diarylethene and functional groups to construct new fluorescence chemosensor.So far,the chemosensor construct fluorescent group and diaryleth to have some novel properties,which are hotspots in this filed.As far as we are aware,recognition of cations and anions at the same conditions based on diarylethenes has rarely been reported.On this basis we designed and synthesized five new fluorescence chemosensors connect with diarylethene.The main content of this paper summarize as follows:In chapter 1,the research background,properties of diarylethene and fluorescence chemosensor,and the type of chemosensors using fluorescein derivatives.Their application in fluorescent switch and ion recognition were intensively introduced.Based on on the survery of the current focus our research subject was brought out.In chapter 2,a new photochromic diarylethene DTE-1 with a triazole-linked fluorescein unit has been synthesized by click chemistry and its multi-controllable fluorescence characteristics have been systematically investigated by the stimulation of light,base/acid,and metal ions.The diarylethene could serve as a fluorescence chemosensor highly selective recognition of Cu²⁺via Fenton reaction-assisted signal amplification.In chapter 3,quinoline was connected with fluorescein hydrazide group to construct new fluorescence chemosensor for Cd²⁺with specific binding site.DTE-2was synthesized by connected chemosensor and diarylethene by Williamson reaction.The fluorencence of DTE-2 after adding Cd²⁺to the solution could be multi-controllable by ligut and EDTA.DTE-2 could be a promising candidate for the construction of a reversible and multi-state fluorescence switch.In chapter 4,three novel photochromic diarylethenes with salicylidene Schiff base substituent was designed and synthesized.Compound DTE-3 and DTE-4 have similar binding site with metal ions,but the property of DTE-4 in recognition is superior to DTE-3.DTE-4 could highly selective towards Zn²⁺and Al³⁺in different solvent system with specific fluorescence signals.Compound DTE-5 could selective towards Al³⁺and CN^-with bimodal methods.DTE-5 could be used as a fluorogenic chemosensor for Al³⁺and colorimetric chemosensor for CN^-.