Construction And Formation Mechanism Of Novel Supra-molecular Aggregates Containing β-Cyclodextrin

Supramolecular chemistry has been defined as the 'chemistry ofmolecular assemblies and of the intermolecular bond'. Since the Nobel Prize forchemistry was awarded to Lehn, Cram and Pedersen for their work in the area in 1987,studies on s upramolecular chemistry have received considerable attention. As one keydivision within supramolecualr chemistry, host-guest chemistry has sprung fromdevelopments in macrocyclic chemistry.During the process of host-guest interaction, one, two or three dimensionalnetwork can be constructed by forming the host-guest complex between the host andguest molecules. Therefore, a change in rheology behavior may be observed and thephase transition may occur eventually.As an important kind of host, cyclodextrin can form stable inclusion complexeswith less polar molecules (guests) that fit tightly inside the cyclodextrin cavity. Thishost-guest interaction is affected not only by guest's polarity and size but also by theenvironment of medium such as temperature, pH, polarity and radiative stimulation.Consequently, the interaction between host and guest can be tuned by varying theseconditions.Based upon this methodology, bis-host and bis-guest supramolecular buildingblocks were designed and prepared in the present study. The supramolecular interactionsbetween them in aqueous solution and at solid state were studied systematically.Polymer bearing guest molecules were designed and synthesized. As that expected, thebridged bis(β-cyclodextrin) can act as host to ferrocene, and they combine ferrocenelabeled on the backbone simultaneously. Based on the interaction of 6-deoxy-6-amino-β-CD and a polymer in common use, poly(acrylic acid), a novel two-componentsupramolecular gel was fabricated. These results are useful for the construction of novelsupramolecular structures and smart soft materials.First, aβ-cyclodextrin dimmer, benzenetetracarboxylic dianhydride bridgedbis(β-cyclodextrin)s was synthesized. Then, N, N'-bis(ferrocenylmethylene)diaminobutane have been prepared with ferrocene and butanediamine as starting materials.Finally, the aim product, the quaternary ammonium salt of N,N'-bis (ferrocenylmethyl- ene)diaminobutane was obtained by reacted with iodomethane. The compositions andstructures of the complexes have been determined and characterized by FTIR, ¹HNMRand elemental analysis. And then, the binding interaction of quaternary ammonium saltof N, N'-bis(ferrocenylmethyl)diaminoethylene and benzenetetracarboxylic dianhydridebridged bis(β-cyclodextrin)s in the aqueous solution and solid states was investigated by¹H NMR, FTIR, DSC CV and TEM. The results indicate that bridged bis(β-cyclodextrin)s can form linear nano-structure aggregates with quaternary ammoniumsalt of N,N'-bis(ferrocenylmethyl)diaminoethylene.In the second part of this dissertation work, ferrocerioyl chloride and ferrocenoyl-methyl diaminoethylene have been prepared with ferrocene carboxylic acid andethylene-diamine as the starting materials. And then, the monomer was. prepared withthe latter. Finally, co-polymers with various ferrocene contents were synthesizedthrough copolymerization with N-isopropylacrylamide as another monmer at differentformulations. The binding interaction of co-polymers and bridged bis(β-cyclodextrin)sin the aqueous solution and solid states was investigated by CV, UV-VIS and SEM. Asexpected, bridged bis(β-cyclodextrin)s can act as a host to free ferrocene, and ferrocenein binding state, which was dound on the backbone of poly(N-isopropylacrylamide) aspendent groups in this case. These results are useful for the construction of novelsupramolecular structures and smart soft materials.In the third part, based on the interaction of 6-deoxy-6-amino-β-CD and a polymerin common use, poly (acrylic acid), a novel two-component supramolecular gel wasfabricated. Microstructure and morphology studies by SEM, revealed that gel adoptsfilm-like lamellar morphologies. XRD, FT-IR, salt effect and acid effect studiesrevealed that intermolecular hydrogen bonds ofβ-CDNH₂, as well as electrostaticinteraction between the carboxyl group of PAA and amido group ofβ-CDNH₂ were themain forces for the formation and maintenance of the aggregates in the gel and thenetwork structures of the gel.