| Supramolecular self-assembly is a very important research field to study biological functions,understand life phenomena and explore the origin of life.At the same time,it is also a rapidly developing and dynamic field.The nature of its interdisciplinary has aroused the wide attention of physicists,theorists,crystallographers,inorganic solid chemists,organic synthetic chemists,biochemists and biologists.In recent years,based on the theory and method of self-assembly,a lot of optical and electrical functional materials,biomimetic materials,molecular machines and devices and other supramolecular materials have been created.These materials display important research value and application prospect in biological fluorescence imaging,information storage,host-guest and other fields.Based on the theory of metal coordination-driven self-assembly,the following work has been done in this thesis:In the second chapter,the flexible amide-bridged multi pyrazole ligands have been synthesized(H2L1-H3L4),which combine the amide NH group that can produce hydrogen bonding and the pyrazole group capable of spontaneously deproton.Dipalladium "molecular metal" corner capable of enhancing electrostatic interaction.Thus,a series of water-soluble supramolecular structures as metal-organic anion receptors(1-5)were assembled by coordination with dimetallic corner[(bpy)2Pd2(NO3)2](NO3)2 or[(dmbpy)2Pd2(NO3)2](NO3)2(bpy=2,2'-bipyridine,dmbpy=4,4'-bimethyl-2,2'-bipyridine).The configuration of receptors can be controlled by both the ligand and the dimetallic corner simultaneously.These complexes were characterized by NMR,MS,IR,TGA and their structures were determined by X-ray single crystal diffraction.It is important that the assemblies 1-5 can bind nitrate anion through amide N-H…anion hydrogen bonding and multiple anion…? interactions.In addition,as complexes(1?NO3-)·3NO3(4?3NO3-)·3NO3-have large cavity and show stable properties,iodine adsorption experiments were carried out.The results of 1H NMR,ESI-MS and TGA showed that complexes(1?NO3-)·3NO3--(4?3NO3-)·3NO3-could adsorb iodine molecules with intact structure.In the third chapter,we designed and synthesized a series of rigid fused ring arylimide bispyrazole ligands(H2L5-H2L13)with different conjugation planes and different coordination angles,which were assembled and coordinated with bimetallic"molecular meta" corners([(bpy)2Pd2(NO3)2](NO3)2 and[(bpy)2Pt2(NO3)2](NO3)2)by removing the protons of pyrazole NH spontaneously in water system.A series of water-soluble square macrocyclic supramolecular assemblies were obtained by 1H NMR monitoring and tracking the assembly process.These macrocyclic structures were analyzed and characterized by 1H NMR and ESI-MS.In Chapter 4,we designed and synthesized three kinds of bifunctional pyrazole carboxylic acid ligands(H2L14-H2L16)with proton switches.These ligands have N,O double coordination sites and NH,COOH double proton switches.According to the theory of hard and soft acid bases(HSAB),the three bifunctional ligands were assembled with different transition metals(Pd2+,Pt2+,Zn2+,C02+,N2+)and/or rare earth metals(La3+,Nd3+,Ce3+,Eu3+,Gd3+,Td3+)through programmed and controllable hierarchical self-assembly,obtaining a series of heterometallic organic supramolecular assemblies.The supramolecular assemblies were characterized by NMR and ESI-MS,and theirs structures were determined by X-ray single crystal diffraction.The primary assemblies show non chiral clamp configurations,while the secondary assemblies display chiral three-dimensional infinite network structures with holes.The results show chiral supramolecular structures were self-assembled from non chiral molecular components,and introduced different metals like d-f shell into supramolecular self-assembly system simultaneously by using programmed hierarchical self-assembly method.Novel d-f heteroelectron related organic heterometallic supramolecular with novel structure and adjustable function were assembled. |
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