Studied On The Synthesis And Properties Of Transition/Lanthanide Complexes Based On Bidentate Acid Ligands

In recent years,coordination polymer?CPs?has attracted many people's attention because of its changeable and novel construction methods and its application in many fields.At present,coordination polymers are used in organic chemistry in the fields of catalysis,chemisorption,luminescent materials,ion recognition,biomimetic probes,magnetic materials and nanomaterials,etc.Inorganic chemistry and nanoscience have made great progress and development.Nowadays,the ligands of N atom and oxygen atom containing sp² hybrid orbitals have become the mainstream ligands of coordination polymers because of their rich and changeable coordination modes and properties.Moreover,the synthesis of coordination polymers is no longer limited to the use of a single ligand or metal,and a variety of ligands involved in the synthesis of coordination polymers?mixed?has become matured.In this paper,6-carboxyl-1H-benzimidazole-2-propionic acid?H₃L?as ligand and hexamethyleneimine as main ligand and terephthalic acid,1,4-naphthalic acid and succinic acid as auxiliary ligands were used by hydrothermal method.Ten transition metal complexes and lanthanide metal complexes were prepared by reflux method and solvent volatilization method.We characterized them by structure and thermal stability.The detection methods include infrared determination of the preliminary structure,X-ray single crystal diffraction to determine the structure,X-ray powder diffraction?PXRD?to determine the product purity,to verify whether it is stable at high temperatures,we used thermogravimetric?TG?and other detection methods.At the same time,some of the complexes were studied in depth,including catalytic properties,luminescent properties and magnetic properties.The specific contents of the study are as follows:1.A benzimidazole derivative,6-carboxyl-1H-benzimidazole-2-propionic acid?H₃L?,was synthesized and characterized.2.Seven coordination polymers,[Cd₃?HL?₄?H₂O?₂]_n?1?[Mn₃?HL?₄?H₂O?]_n?2?[Eu₃?HL?₂?H₂O?_2·2Cl]_n?3?[Pr₃?HL?₂?H₂O?_2·2Cl]_n?4?[Ho₃?HL?₂?H₂O?_2·2Cl]_n?5?[Dy₃?HL?₂?H₂O?_2·2Cl]_n?6?[Yb₃?HL?₂?H₂O?_2·2Cl]_n?7?were synthesized using H₃L as ligand and chloride under hydrothermal conditions.A series of structural characterizations were carried out,in which complexes[Cd₃?HL?₄?H₂O?₂]_n and[Mn₃?HL?₄?H₂O?]_nwere2Dstructure,and[Eu₃?HL?₂?H₂O?_2·2Cl]_n,[Pr₃?HL?₂?H₂O?_2·2Cl]_n,[Ho₃?HL?₂?H₂O?_2·2Cl]_n,[Dy₃?HL?₂?H₂O?_2·2Cl]_n and[Yb₃?HL?₂?H₂O?_2·2Cl]_n were 1D chain structure.A 3D supramolecular structure were formed by hydrogen bonds and?…?stacking interactions.The effects of coordination mode and environment on the structure and properties of coordination polymers were discussed.The solid-state fluorescence properties of complexes[Cd₃?HL?₄?H₂O?₂]_n,[Ln₃?HL?₂?H₂O?_2·2Cl]_n and the magnetic properties of complexes[Eu₃?HL?₂?H₂O?_2·2Cl]_n,[Pr₃?HL?₂?H₂O?_2·2Cl]_n and[Ho₃?HL?₂?H₂O?_2·2Cl]_n were studied.3.[Cu?HMT?₂?BDC?₂]_n?8?[Co₃?HMT?₂?NDC?₆?DMF?₈]_n?9?[Cd₃?HMT?₂?SA?₇?CH₃OH?₄]_n?10?were synthesized using hexamethylimine?HMT?as auxiliary ligand,p-phthalic acid?PA?,1,4-naphthyldicarboxylic acid?NDC?and?SA?succinate as main ligands.The structures of three coordination polymers were characterized,including[Cu?HMT?₂?BDC?₂]_nwas 1D chainstructure,[Co₃?HMT?₂?NDC?₆?DMF?₈]_n and[Cd₃?HMT?₂?SA?₇?CH₃OH?₄]_n were 3D structure of the complex.The effects of coordination environment and coordination mode on its structure and properties were also discussed.In addition,the catalytic properties of[Cu?HMT?₂?BDC?₂]_n,the magnetic properties of complexes[Cu?HMT?₂?BDC?₂]_n,[Co₃?HMT?₂?NDC?₆?DMF?₈]_n and solid-state fluorescence properties of complex[Cd₃?HMT?₂?SA?₇?CH₃OH?₄]_n were discussed and studied.