Synthesis Of Legocycles And Study On Adsorption And Separation Performance Of Macrocycle

In 1987,the Nobel Prize in Chemistry was awarded to C.J Pedersen?J.M Lehn ? D.J Cram because of their outstanding contributions in the field of supramolecular chemistry.What metioned aboved marked the birth of supramolecular chemistry in science.What's more,designing and synthesizing supramolecular star macrocycles are allways the hot point in supramolecular chemistry.In 2015,a new type of supramolecular macrocyele,biphenylarene synthesized from 4,4'-ethoxybiphenyl monomer was first demonstrated by our group.In 2017,we changed the monomer alkoxy modification position from 4,4' to2,2'.Through reducing its ring-forming steric hindrance,we improved its yields and increased the types of products.In this article,for the sake of increasing the reactivity,we use2,4-alkoxybenzene for ring-closure units.The change of ring-closing unit not only increased the cyclization activity,but also gave more modifiable sites for macrocycles.At the same time,the functional elementary molecules can be embedded between the units,which can adjust the cavity size,electrical properties,and introduced the unique properties into the macrocycle.This kind of functional construction strategy is similar to LEGO toys which can be constructed through free combination,so we named these macrocycle Legocycles(LC).In addition,the macrocyclic which obtained by one pot method(99% yield)from 2,2',4,4'-tetramethoxybiphenyl monomers were applied into nonporous adaptive crystal materials(NACS).It can separate cis&trans-1,2-dichloroethylene with high selectivity.Specifically,our work has been carried out in the following areas:(1)Based on the previous work,series of Legocycles were synthesized by using 2,4-dimethoxybenzene as the ring-closing units and functional groups as the linker.These macrocycles have the advantages such as: simple preparation method,high reactivity and replaceable functional groups.At the same time,according to theexperimental results,the cyclization rule was studied.We found that the linear monomer molecules tend to form trimer or cycle with higher polymerization,while the V-monomer molecules tend to form dimer.(2)On the basis of the synthesis of Legocycles,we also carried out derivatization experiments of these new macrocyclic molecules.We found that the macrocycle can not only perform perhydroxy derivatization,but also the methoxy group can be replaced by a bromoalkoxy chain.It established the foundation for its anionic and cationic water-soluble derivatization.Besides,we have also conducted hybrid copolymerization of macrocycles and successfully synthesized two types of hybrid macrocycles.It can be believed that we can construct supramolecular polymer materials based on these hybrid macrocycles in the near future.(3)The newly synthesized 2,2',4,4'-tetramethoxybiphenylarene(Me BP3)was used as nonporous adaptive crystals material for the separation of cis-1,2-dichloroethylene and trans-1,2-dichloroethylene.It can selectively adsorb cis-1,2-dichloroethylene in a mixed gas,with 96.4% selectivity.This result showed its potential for the removal of trace trans-1,2-dichloroethylene impurities from cis-1,2-dichloroethylene gas.Generally speaking,Legocycles were a new type of functionalized supramolecular macrocycles with the feature of high yields,unique structures,efficient synthesis,and simple modification.What's more,we also explored the application in adsorption and separation of alkene isomer.We believed that the research results of Legocycles can permeate all aspects of various fields and contribute to society in the near future.