Synthesis,Structure And Fluorescence Probe Properties Of Thioether Polyphenylcarboxylic Acid Coordination Polymers

In this thesis,three thioether polyphenylcarboxylic acids with similar structures are selected:5-(2-carboxy-phenylsulfanyl)-isophthalic acid(H3CPIB),2,5-bis-(4-carboxy-phenylsulfanyl)-terephthalic acid(H4PSTP)and 2-(4-carboxy-phenylsulfanyl))-terephthalic acid(H3BPH)as the main ligands,it reacts with d10 metal ions and alkaline earth metal ions,some of which are combined with N-containing auxiliary ligands,and nine kinds of coordination polymers with fluorescent properties were synthesized by solvothermal method.The crystal structure of the complex 1-9 was tested and analyzed by various instruments and means,and the performance of the fluorescent probe for detecting metal ions,inorganic anions and small organic molecules was investigated,and the structure-activity relationship was studied.1.In the synthesis conditions of complexes 1-3,the temperature is the same,and the auxiliary,metal ions and solvent conditions are different.H3CPIB is the main ligand.Three new single crystal complexes 1-3 of different configurations were assembled by solvothermal synthesis at 130 ?,namely {[Zn2(CPIB)(OH)(H2O)]·3H2O}n(1)?{[Ba4(CPIB)2(HCPIB)(H2O)]·10H2O}n(2)?{[Cd3(CPIB)2(phen)3(DMA)(H2O)]·5H2O}n(3).Complex 1 belongs to the triclinic system,and three benzenecarboxylic acids in the ligand coordinate with Zn(II)to form a two-dimensional network structure by means of a monodentate bridge;complex 2 belongs to the orthorhombic system,and three benzenecarboxylic acids in the ligand coordinate with Ba(?)to form a three-dimensional structure through the combination of unidentate bridging and bidentate chelation;complex 3 belongs to the monoclinic system,and the auxiliary ligand phen is added.The three benzenecarboxylic acids in the main ligand are coordinated with Cd(?)to form a two-dimensional structure containing pores through a combination of unidental bridging and bidentate chelation.Complexes 1-3 all have good chemical and thermal stability,and they have certain selectivity for dispersing solvents in terms of fluorescence.Among them,complex 3 can also effectively sense ketone reagents,which is beneficial to future practical fluorescence sensing applications.Through a series of fluorescence quenching experiments,it was found that complexes 1-3 have no fluorescent quenching effect on metal ions,but have fluorescent quenching responses to small organic molecules 2,4,6-trinitrophenol(TNP)and ornidazole(ONZ).Similarly,all three complexes have the highest sensitivity and selectivity to 2,4,6-trinitrophenol.2.In the synthesis conditions of complexes 4-6,the auxiliary and the metal ions were different.H4PSTP as the main ligand,Cd2+ and Ba2+ metal ions as the metal center,and different auxiliary ligands 2,2'-bipyridine(2,2'-bpy)and di-pyridin-4-yl-diazene(4-DiPyDz)were synthesized in the same solvent at 120? through different solvent ratios to assemble three new monomers with different configurations.Crystal complexes 4-6,[Ba(PSTP)0.5(H2O)]n(4)?{[Cd(PSTP)0.5(2,2'-bpy)(DMF)]}n(5)?[Cd(PSTP)0.5(4-DiPyDz)]n(6).Complexes 4 and 5 belong to the triclinic system,P1 space group.However,in the construction,the metal center of 4 is Ba(?),large ionic radius and high coordination number are conducive to the construction of high-dimensional complexes and coordination with the main ligand to form a three-dimensional complex;and 5 is Cd(?)binding short chain N-containing auxiliary ligand 2,2'-bpy forms a two-dimensional structure.Complex 6 belongs to the monoclinic system.The long-chain N-containing 4-DiPyDz is added,and the cross auxiliary is connected to the metal ion to form a three-dimensional structure of the complex.Complexes 4-6 all showed good fluorescent probe performance.Among them,the fluorescence of the complex 4 can be effectively quenched in the water environment,and the complex 5 can also effectively sense ketone reagents,which is beneficial to future practical fluorescence sensing applications.Through a series of fluorescence quenching experiments,it was found that complexes 4-6 have no fluorescent quenching effect on metal ions.However,if complex 4 is dispersed in water,In3+ can be effectively detected by the fluorescence enhancement effect.4-6 has a certain fluorescence quenching response to small organic molecules.Due to the different structures of different resonance energy transfer,the quenching effects of the three complexes are also different.3.In the synthesis conditions of complexes 7-9,the metal ions,temperature and solvent were kept the same.Only the auxiliary ligands were different.With H3BPH as the main ligand and Zn2+ as the metal center,different auxiliary ligands 2,2'-bipyridine and di-pyridin-3-yl-diazene,through the solvothermal synthesis in the same solvent ratio,assembled three new single crystal complexes of different configurations 7-9,{[Zn5(BPH)2(OH)4]·0.5H2O}n(7)?{[Zn3(BPH)2(2,2'-bpy)2]·(CH3CN)3}n(8)?{[Zn9(BPH)6(3-DiPyDz)3(H2O)]·(CH3CN)3}n(9).Complex 7-9 belongs to the triclinic system,the monoclinic system and the trigonal system.All of them coordinate with Zn(II)to obtain a new three-dimensional complex with holes.Complexes 7-9 have good chemical and thermal stability,and there are some similarities in fluorescent quenching performance.First of all,7-9 cannot be used as fluorescent probes to detect metal ions.Secondly,according to the quenching volume and quenching constant analysis,7-9 all have fluorescence quenching response to Cr2O72-,and the quenching constants are very similar,indicating that the quenching ability is similar.Finally,after adding different organic small molecules to complexes 7-9,the strongest quenching rate is TNP molecules,which can be used as fluorescent probes to detect 2,4,6-trinitrophenol.