Study On Design,Synthesis And Properties Of Coumarin Anion Recognition Receptor

Recognition and sensing of anions have potential applications in Environmental Science,medical science and other fields.The Fluorescence analysis refers to the change of light emission and absorption properties to the analysis of the fluorescence analysis method.This method has the advantages of simple operation,high sensitivity and favored by the people.We put the fluorescent probe according to different fluorophores to classify can get rhodamine,fluorescein,coumarin and so on.It is worth mentioning that coumarin derivatives as fluorescent probe molecules generally have good light stability,high fluorescence quantum yield and large Stokes shift has been of concern to the people.Ring of coumarin compounds most have fluorescence due to its chromophore is lactone class of natural products,which are widely used in fine chemical industry,medicine,dyes and other fields.In this paper,4 types of anion receptors containing coumarin derivatives of hydrazide groups were designed,synthesized,and by UV visible spectra analysis,fluorescence spectroscopy and NMR titration analysis method to research them with various anions(F-,Cl-,Br-,I-,OH-,AcO-,H2PO4-)interaction.The main contents are as follows:1.The molecular fluorescent probe Z1 was designed and synthesized by using coumarin derivatives containing hydrazide group with the p-nitro salicylicaldehyde reaction,and was characterized by the method of H NMR,IR,MS etc.The host Z1 shows the phenomenon of fluorescence quenching to anions(F-,OH-,AcO-,H2PO4-).In the recognition process,the NH on hydrazide groups of host Z1 forms a hydrogen bond with the anion,Caused by the internal molecular increased charge density so that is conducive to the transfer charge,resulting in the occurrence of fluorescence quenching.2.The molecular fluorescent probe Z2 was designed and synthesized,by the coumarin derivatives containing acyl hydrazine with p-nitro azo salicylicaldehyde reaction,and was characterized by the method of 1H NMR,IR,MS etc.The host Z2 manifests ratiometric fluorescence response to anions(F-,OH-,AcO-,H2PO4-),which can be used in poto-induced charge transfer(PCT)mechanism to explain.3.The molecular fluorescent probe Z3 was designed and synthesized through phenprocoumon containing hydrazine group with p-nitro salicylicaldehyde reaction,and was characterized by the method of 1 NMR,IR,MS etc.The host Z3 displays fluorescence quenching phenomenon to anions(F-,OH-,AcO?,H2PO4-4.The molecular fluorescent probe Z4 was designed and synthesized by using phenprocoumon containing acyl hydrazine with p-nitro azo salicylicaldehyde reaction,and was characterized by the method of 1H NMR,IR,MS etc.The host Z4 presents the fluorescence enhancement properties to anions(F-,OH-,AcO-,H2PO4-).Most of the fluoreseence sensor is fluorescence quenching,which is not eonducive to the signal output,and thus,the fluorescence enhancement of anion receptor development will become the focus of our work...