Synthesis Of Pagoda[n] Arenes And Studies Of Its Selective Bonding Behavior

Supramolecular chemistry is an emerging chemical discipline.In recent years,a variety of new macrocyclic aromatic hydrocarbons have attracted more and more interest.The development of new macrocyclic aromatic hydrocarbons with special structural characteristics and a variety of host-guest complex properties has also become a new hotspot in macrocyclic and supramolecular chemistry.As the latest generation of macrocyclic molecules,Pagoda[n]arenes has attracted extensive attention and research from chemical scientists since it was first reported in 2020.This thesis is mainly based on the main and guest chemical properties of Pagoda[n]arenes to explore the research.In the first part of the work,reference synthesized Pagoda[n]arenes(n= 4,5)and synthesized its complexed guest.The structure of the subject and object is confirmed by the NMR spectrum,and the study of the subject and object can be carried out.In the second part of the work,the host-guest properties of the Pagoda[n]arenes and the tropylium cation are investigated.Nuclear magnetic resonance,mass spectrometry,fluorescence spectroscopy,and ultraviolet absorption spectroscopy were used to determine whether the host and guest complex,complex ratio,and complex intensity.It was found that the complexation strength of Pagoda[n]arenes with tropylium cation is much higher than that of macroring previously reported.In addition,it was found that the guest binding and release process in host-guest complex could be effectively controlled by redox stimulation,and the response process could be visually observed by the color change of the solution.To our knowledge,this represents the first visible redox stimulus responsive host-guest system formed by Pagoda[n]arenes with a guest,and this work will provide new perspectives on Pagoda[n]arenes applications in supramolecular chemistry and functional materials.In the third part,the host-guest properties of Pagoda[n]arenes and pyridine cations are studied.Pyridine cations with different chain lengths and different anions were synthesized.The complexation,complexation ratio and complexation strength of host and guest were determined by means of nuclear magnetism,mass spectrometry,fluorescence spectrum and ultraviolet absorption spectrum.The effects of different chain lengths and anions on host-guest complex systems were analyzed and compared.In addition,the weaker the binding capacity of the anion attached to the cation,the stronger the binding strength of the host and guest.Our preliminary study on the host-guest chemistry of Pagoda[n]arenes and cationic guest has enriched the study of the host-guest chemistry of Pagoda[n]arenes and promoted the exploration and application of the new host-guest complexation system of Pagoda[n]arenes.