Study On Synthesis Of Fluorescence Chemosensors Based On Phenanthroline Derivatives And Their Sensing Properties

In recent years,fluorescence sensors which are simple,high sensitivity,good selectivity and otheradvantages of detection methods have attracted much attention.However,the reported fluorescence sensors were performed in organic solvents through hydrogen bonds,and limited the detection of chiral carboxylic acid anions in water due to the destructive hydrogen bonding of the solvent in aqueous solvents.Therefore,it is of great significance to design and synthesize a fluorescence sensor to achieve the enantioselective recognition of metal ions and chiral carboxylic acid anions in aqueous solvents.1,10-phenanthroline,as a stable?-electron acceptor,could be complexed with metal ions byusing its two nitrogen atoms,then by introducing heteroatoms such as N or O to achieve enantioselective recognition of chiral carboxylic acid anions.In this thesis,fluorescent sensors based on phenanthroline fluorophores were designed andsynthesized,and their structures were confirmed by ¹H NMR,¹³C NMR,MS and IR.The binding properties between these sensors and common metal ions and chiral carboxylic acid anions?dibenzoyltartrate et al?were studies by fluorescence spectroscopy.The main contents are as follows:?1?The design principle of molecular recognition and fluorescence chemical sensor is reviewed.The research progress of chiral anions and metal ions is introduced.Based on this,the design idea of this thesis is proposed.?2?A Schiff base fluorescence sensor II-1 was synthesized based on phenanthroline ando-hydroxyaniline.The selective recognition of sensor II-1 towards metal ions in aqueous solvents was studied by UV and fluorescence spectroscopy.The complex ratio of 1:1 between sensor II-1 and metal Pb²⁺was obtained by the Benesi-Hildebrand equation.The chemical stoichiometry of sensor II-1 and Pb²⁺was verified by Job experiment.The binding mode between sensor II-1 and Pb²⁺was obtained by using NMR titration and quantum chemistry calculations.The detection of sensor II-1 to Pb²⁺in living PC-12 cells was investigated by cell imaging experiments,which had broadened the range of detection of Pb²⁺in biological and chemical studies.?3?Fluorescent chemical sensors III-1 and III-2 based on phenanthroline derivatives were synthesized.The selective recognition of sensors III-1 and III-2 towards metal ions were studied by fluorescence spectra.In addition,we proposed binding modes between sensors III-1 and Cd²⁺combining with fluorescence spectroscopy,NMR and gaussion calculations.The enantioselective recognition of III-1-Cd²⁺and III-2-Cd²⁺in aqueous solution towards chiral methoxyphenylacetic anions were studied by fluorescence spectroscopy.Furthermore,the ability of the sensor III-1 to recognize Cd²⁺and chiral methoxyphenylacetic anions in living HeLa cells was further studied by cell imaging experiments.?4?The fluorescence sensors IV-1,IV-2 and IV-3 were synthesized.The selective recognition ofsensors IV-1,IV-2 and IV-3 towards metal ions were studied by fluorescence spectra.Fluorescence spectroscopy experiments were conducted to study the enantioselectivity of IV-1-Eu³⁺,IV-2-Eu³⁺and IV-3-Eu³⁺.The identification of the sensor IV-1 towards Eu³⁺and the sensor IV-1-Eu³⁺for L-/D-Ma was directly observed by the naked eye.The ability of the sensor IV-1 to recognize Eu³⁺and chiral malate anion in living PC-12 cells was further studied by cell imaging experiments.?5?Phenanthroline Schiff base fluorescence chemical sensors V-1 and V-2 were synthesized byusing phenanthroline and mandelic acid as raw materials.Their selective detection of sensors V-1 and V-2towards metal ions were studied through fluorescence spectroscopy.And the enantioselective recognition of chiral carboxylic acid anions was studied by fluorescence spectroscopy.The identification of the sensor V-1towards Eu³⁺and the sensor V-1-Eu³⁺for L-/D-MA was directly observed by the naked eye.