| The cucurbit[n]urils is a new type of the highly symmetric barrel macrocyclic molecular compound after cyclodextrin, crown ether and calixarenes. It’s the subject which attract much interest in recent years because of its special structure and its potential applications as functional materials. The host-guest chemistry, as the core research project of the cucurbiturils chemistry, there have been quite a few studies focusing on supramolecular assemblies of Q[n]s themselves in recent years. Combination of literature works and the experimental result in key laboratory of macrocyclic and supramolecular chemistry of Guizhou province, the construction of supramolecular assemblies between cucurbit[n]urils and the Linear and dendritic molecules have become the main contents in this thesis.In the present work, Series of different linear molecules with a range of functional groups and multiple binding sites and the dendritic molecules which were based on porphyrin were designed and synthesized, while structures and interaction of cucurbit[n]urils with these guest were investigated by using NMR spectroscopic methods, electronic absorption spectroscopy, fluorescence spectroscopic, isothermal titration calorimetry(ITC) and single-crystal X-ray diffraction analysis. The experimental results showed that:(1) Cucurbit[7]uril can include N,N’-bis(4-dimethylaminobenzyl)-decane-1,10-diamine forming a pseudorotaxane inclusion complexes or dumbbell-shaped inclusion complexes by changed the ratio of the host and guest.(2) In aqueous solution, symmetrical α,α’,δ,δ’-tetramethyl-cucurbit[6]uril(TMeQ[6]) forms 1:1 inclusion complexes with three 4-pyrrolidinopyridine derivatives, specifically 4-pyrrolidinopyridine, N-butyl-4-pyrrolidinopyridine, and N-amyl-4-pyrrolidinopyridine. Generally, TMeQ[6] preferentially accommodates the pyridyl moiety of these guests, which was confirmed by the crystal structures of its complexes with 4-pyrrolidinopyridine and N-butyl-4-pyrrolidinopyridine. Moreover, TMeQ[6] can form a thermodynamic inclusion complex with 4-pyrrolidinopyridine at elevated temperatures. The unthreading and rethreading of the TMeQ[6] ring can simulate a molecular-level plug/socket system, that can be reversibly driven by Ba2+/SO42?, and is accompanied by obvious changes in the UV absorption spectrum, both in wavelength and intensity.(3) Binding interactions between TMeQ[6] and a series of alkyldiammonium ions in aqueous solution and in solid state were investigated. The guest 1,2-ethanediammonium is located outside of the TMeQ[6] portal, while the other six alkyldiammonium guests(from 1,3-propanediammonium to 1,12-dodecanediammonium) can be accommodated in the TMeQ[6] cavity, forming 1:1 inclusion complexes. Most importantly, the long chain alkyldiammoniums(1,8-octanediammonium and 1,10-decanediammonium) take contorted conformation when bound within the TMeQ[6] cavity.(4) 5,10,15,20-Tetra-(N-hetyl-4-pyridyl) porphyrin and 5,10,15,20-Tetra-(N,N,N-trimetyl-4-butoxyl-phenyl) porphyrin were designed and synthesized. In aqueous solution, TMeQ[6] preferentially includes the alkyl of these guests forms 4:1 inclusion complexes.(5) The interaction of a symmetrical α,α’,δ,δ’-tetramethyl-cucurbit[6]uril with a series of lanthanide cations(Ln3+) was investigated in neutral water and in acidic solution. Analysis of single crystal x-ray diffraction revealed that interaction products gave rise to crystals with different isomorphous groups under different synthetic conditions. All such differences in the interaction between TMeQ[6] and Ln3+ could be used isolating heavier Ln3+ from their lighter counterparts in neutral solution, and lighter lanthanide cations from their heavier counterparts in acidic solution.This observation not only contributes to a deeper understanding of the interactions between redox guests and macrocycle hosts, but may also expedite the design and construction of novel molecular machines. |
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