Hydroxy Cucurbit - Heteropolyacid Supramolecular Self-assembly To Build Entity

The cucurbit[n]urils (Q[n]s) is a new type of supramolecular macrocycliccompound with novel structure and properties attracting numerous attentions. Becauseof the poor solubility of the Q[n]s in commonly, the research of modifiedcucurbit[n]urils became a hot issue at present. Inaddition, Polyoxometallates (POMs),a wide class of metal oxide clusters generally characterized by large molecularstructures have a long history of development and is widely applied to catalyticreaction, life science, especially in optical, electrical, magnetic and drugs discipline.Using the outer-surface interaction of Q[n]s, construction ofcucurbit[n]uril-polyoxometallate-based supramolecular assemblies and investigationof the consequent novel properties have been attracting extensively attention in recentyears.The thesis smmaried research development of the cucurbiturils coordinationchemistry and the construction of POMs with (HO)10Q[5]. On the basis of the existingsynthetic route, the synthetic route was optimized and characterized in the thesis.Based on previous researches on construction of thecucurbit[n]uril-polyoxometallate-based supramolecular assemblies, theperhydroxycucurbit[5]uril ((HO)10Q[5]) and phosphomolybdic acid (POMs) wasselected as basic building blocks, and the (HO)10Q[5]-POMs-based supramolecularassemblies have been investigated in this thesis.In the first systems, using [PMo12O40]3anion as a structure inducer,we preparedtwo new types of (HO)10Q[5]-based supramolecular assemblies, which wererespectively porous channel structure constructed by (HO)10Q[5]-[PMo12O40]3andK+/(HO)10Q[5]-[PMo12O40]3. It was noted that structure of K+/(HO)10Q[5]-[PMo12O40]3was based on two-dimensional networks structure of (HO)10Q[5]-[PMo12O40]3, in which [PMo12O40]3played a key rule in perhydroxycucurbit[5]uril.The driving forces included:1) classical hydrogen bonding of the functionalizedhydroxyl groups on the back of (HO)10Q[5] molecules,2) unusual hydrogen bondingof the methylene groups on the back of (HO)10Q[5] molecules, and3) interaction between electron-deficient carbon sites of carbonyl groups of (HO)10Q[5] moleculeswith the electron-rich oxygen sites of Mo–O groups from [PMo12O40]3anions. Anadditional electrostatic interaction could exist in K+-coordinated (HO)10Q[5]complexes.Another the coordination and supramolecular assemblies ofpotassium/lanthanides cations to perhydroxycucurbit[5]uril in the presence of[PMo12O40]3–anions show significant differences that light lanthanides are selectedto coordinate to (HO)10Q[5] in the presence of potassium cations but heavierlanthanides are not, which could be used for the isolation of light lanthanides fromtheir heavier counterparts.