Synthesis And Recognition Of Organic Fluorescent Molecules Based On Coumarin,Pyrene And Anthracene As Chromophores

Fluorescent molecule is a kind of substance that emits light when excited by light or electricity,which include inorganic fluorescent molecule and organic fluorescent molecule.Compared with inorganic fluorescent compounds,organic fluorescent materials are widely used in many areas such as,dye coloring,paper brightener or ink,organic electroluminescence,fluorescent label and fluorescent probes,etc.The study of multifunctional organic fluorescent molecules has always been one of the hot spots in the field of scientific research.The fluorescence chemosensor is one of the important applications of fluorescent substances,it is based on the principle of molecular recognition,by identifying the signal to color changes or fluorescence signals and other forms of output.Fluorescence has a very good sensitivity,so fluorescent chemosensors have advantages of the lower detection limit comparing to traditional detection technology,which achieve the visual inspection of these measured substances.The main work of this paper is to summarize the organic chemosensors that have been discovered and synthesized,and to design and modify organic fluorescent molecules to meet the requirements for rapid,efficient and selective identification of ions.The detailed contents are as following:The first chapter is the introduction section.First,the fluorescent compounds and fluorescence spectra are introduced and the recognition mechanism of the fluorescent molecular sensors is summarized.Then,the research progress of the sensor which based on coumarin derivatives,pyrene derivatives and anthracene derivatives as chromophores is briefly reviewed in the application of ion recognition.Finally,combining with the research summary and the laboratory conditions and working basis,this paper puts forward the research idea of this paper.In the second chapter,in view of the high quantum yield,the large displacement of Stokes and the stability of light stability of coumarin fluorescent compounds,the coumarin-based chemosensor 1 was designed and synthesized,which could sequentially recognize copper ions and cyanide.The structure of fluorescence chemosensor 1 was indentified by ¹H NMR,¹³C NMR and MS.The fluorescence property of this chemosensor were analyzed by fluorescence spectrophotometer,and the results showed that it had good selectivity and high selectivity and sensitivity for cyanide ion and copper ion,and the calculated detection limit lines can be reached to 2.54×10^-7 M and 4.16×10^-7 M for copper ion and cyanide ion detection respectively.In the third chapter,the organic fluorescent chemosensor 2 besed on pyrene as the fluorescent chromophore and DPA as the recognition group were designed and synthesized with high fluorescence quantum efficiency and long fluorescence lifetime.The results showed that it could selectively sensing zinc ion with fluorescence quenching.In the fourth chapter,starting from anthrone as raw material,the chemosenor 3 was synthesized by one-step reaction with hydroxylamine hydrochloric acid.This chemosensor had the advantages of good sensitivity and selectivity,fast response time for hypochlorite ion and had potential applications in the field of environmental monitoring and bioanalysis.