The Research On The Construction And Stimuli-responsive Behaviors Of Water Soluble Pseudorotaxane And Polyrotaxane Based On Cucurbituril And Cyclodextrin

Rotaxane and pseudorotaxane,one of the erailiest molecular machine models,are the hotspot in supramolecular chemistry due to their unique structure and fascinating stimuli-responsive behaviors.However,most of rotaxanes and pesudorotaxanes are prepared in organic solvents and required complicated synthesis.Meanwhile,cyclodextrin and cucurbituril works as two most important macrocyclic host molecules,which display abundant binding behaviors in aqueous solution.Hence,in this paper,various guest molecules bearing special binding sites were synthesized and utilized to construct water-soluble pseudo[n]rotaxanes and polyrotaxanes with cyclodextrin and cucurbituril.Thereafter,their stimuli-responsive behaviors were investigated.The main contents are as follows:1.The development of supramolecular chemistry is briefly introduced.Then,the latest researches on the roraxane,pesudorotaxane and polyrotaxane based on cyclodextrin and cucurbituril are reviewed.2.Azobenzene-bridged viologen dimer and s-tripidylbenzene-bridged naphthalene trimer were synthesized as guest molecules,whose binding behaviors with cyclodextrin and cucurbituril were further investigated.With these results in hand,various pseudo[n]rotaxane and polyrotaxane were constructed via host-guest interaction,and their stimuli-responsive behaviors were further investigated.3.Viologen and fluorene modified azobenzene derivative and s-tripidylbenzene-bridged naphthalene trimer was utilized as guest molecules,and their binding behaviors with cyclodextrin and cucurbituril were investigated.Based on these,various pseudo[n]rotaxanes were fabricated.Interestingly,a cucurbit[8]uril linked [4]rotaxane were obtained by the 1:1:1 binding behavior of viologen,naphthalene and cucurbit[8]uril.In this work,a succession of rotaxane and pseudorotaxane were successfully constructed via self-assembly based on host-guest interaction,which provide a novel way for complex rotaxane fabrication.4.Triazine-bridged semi-viologen trimer was designed and synthesized as guest molecule.Taking advantage of the different binding behaviors,in which 1:2inclusion complex of semi-viologen with cucurbit[8]uril and 1:1 inclusion complex of viologen with cucurbit[8]uril,a p H stimuli-responsive polyrotaxane was successfully constructed.