Structure And Properties Of Supramolecular System Based On Cryptand

As the basis of supramolecular chemistry,the macrocyclic molecular of generation after generation is found to be able to combine with guest molecular with special properties quickly and effectively.The supramolecular compounds are constructed by hydrogen bond,dipole-dipole,coordination,Fan Dehua force,π-π,and hydrophilicity hydrophobicity between the host molecular and the guest molecular.Pseudorotaxane and rotaxane are typical molecular machines constructed from the host and guest interaction,in which the chain guest can be included in the cavity of the macrocyclic molecular through intermolecular interaction.Rotaxane is developed from pseudorotaxane,but in rotaxane,both ends of the thread component there are introduced large stopper group to prevent the macrocyclic molecular from falling off the chain component.Through studying of the mechanism of host-guest interaction,the supramolecular has attracted more and more attention in life sciences and intelligent materials.Based on the classic crown ether and cryptand,we have constructed the supramolecular polymer and fluorescent molecule switch.In chapter 1,the development of supramolecular chemistry,application of crown ethers and cryptand are summarized.The molecular machines based on crown ethers and cryptand,the application of molecular machines in polymers,ion recognition and molecular switches are introduced.In chapter 2,in which BMP32C10 motif can bind with paraquat 2-2 while DB24C8 motif can bind with dibenzylammonium salt 2-3 in spite of the electrostatic repulsion between guests 2-2 and 2-3.On this basis,we further synthesized the allelic bipyridine guest 2-4 and the allelic dibenzylammonium guest 2-5,and ulteriorly we constructed a supramolecular polymer which could be regulated by acid and base.In chapter 3,the binaphthol group and coumarin group were introduced to the third arms of the BMP32C10.The host and guest interaction between the two cryptands and pyridine guests could be well regulated by adding acid/base,and the two cryptands and 4,4-bipyridine have fluorescence responsiveness,which could be used as fluorescent molecular switch regulated by acid/base.To sum up,the construction of pseudorotaxanes were carried out with crown ether and cryptand as macrocyclic host,and the regulatory property and stimulus responsiveness of these supramolecular materials were preliminarily explored,which provided useful reference for molecular recognition and supramolecular intelligent materials.