Synthesis,Identification And Adsorption Properties Of Lanthanide Complexes Based On Flexible Carboxylic Acid Ligands

Due to the unique luminescent properties of lanthanide ions and the strong coodination ability of carboxylic acid,their complexes have potential applications in in recognition,adsorption,fluorescent materials and catalysts,etc.In this paper,a series of binuclear lanthanide complexes and six cage lanthanide/transition metal complexes have successfully sythsized based on carboxylic acid ligands,and characterized by infrared spectroscopy(IR),powder diffraction(PXRD),thermogravimetric analysis(TGA),ultraviolet absorption(UV-vis)and single crystal diffraction,etc.(1)Using 2-formylphenoxyacetic acid(L1)and 1,10-phenanthroline as ligands,three isostructural binuclear lanthanide complexes,namely[Ln₂(L1)₆(phen)₂{Ln=Eu(1),Tb(2),Dy(3)}],have been synthesized and characterized under solvothermal conditions.Fluorescence measurements reveal that the complex 1 shows good selectivity and sensitivity in the detection of 2,4,6-trinitrophenol(TNP)in the acetonitrile solution.(2)Using isophthalaldehyde contained 3-amino-4-methylbenzoic acid(L2)and1,10-phenanthroline as ligands,a series of isostructural tetranuclear cage lanthanide complexes,[Ln₄(L2)₆(phen)₂(DMF)₄�DMF{Ln=Eu(4),Pr(5),La(6),Sm(7)}]have been synthesized.Experiments indicate that complexes(4-7)can sense Fe(III)ion in aqueous solution with naked eyes.In addition,organic dyes adsorption experiments were performed,and the results exhibited that complex 4 and 7 had better adsorption effects on eosin B(EB)in wastewater after 7 hours of adsorption.The adsorption capacity and the decolorization rate are 26.42 mg/g and 94.10%for complex 4;and21.08 mg/g and 84.44%for complex 7,respectively.(3)Using 2-carboxybenzaldehyde contained 3-amino-4-chlorobenzoic acid(L3)and 2-carboxybenzaldehyde contained 3-amino-4-methylbenzoic acid(L4)as ligand,two tetranuclear cage cooper complexes have been synthesized,and the structures and coordination models of complexes were analyzed.In addition,the interaction between the complexes and the biological macromolecules(BSA and ct-DNA)were explored,respectively.