| Supramolecular chemistry is the study on various non-covalent interactions (such as electrostatic attraction, hydrogen bonding arrays, host-guest inclusion, etc.) and the structures or functions of supramolecular materials fabricated by these non-covalent interactions. The chemistry of molecular information, including replication, transfer, and fabrication on molecular and supramolecular level, could be achieved through appropriate manipulation of the non-covalent interactions. The research of supramolecular systems is helpful to learn about their mechanism and further to construct highly ordered functional materials. The present thesis is related to the design and assembly of supramolecular aggregates using ionic attraction and cyclodextrins inclusion as main driving forces, and the following assembly systems were studied in detail.1. Through a facile ionic self-assembly (ISA), the organic nanosticks by complexing of 4-aminoazobenzene hydrochloride (AzoHCl) and 1-Adamantanamine hydro-chloride (NaDC) have been synthesized. The properties and structures of the nanosticks are characterized respectively by various techniques including 1H NMR, POM, TEM, SEM, LCSM, DSC/TGA, XRD, and UV-visible spectroscopy. The stoichiometry between AzoHCl and NaDC in the complexes is determined as a 1:2 molar ratio. The basic building block is composed of one AzoHCl combined with two NaDC by electrostatic interaction and hydrogen bond respectively, which proves that electrostatic interaction is not the only main driving force in ISA, and other interactions such as H-bonding may also be important driving force cooperated with electrostatic interaction. The nanosticks with well crystalline and fluorescent feature could be observed via a laser con-focal scanning microscopy (LCSM). Various functional supramolecular materials could be produced via such a facial ISA strategy using small organic molecules with functional groups.2. The ionic self-assembled organic single-crystals are obtained through complexing two functional molecules, sodium deoxycholate (NaDC) and 1-Adamantanamine hydro-chloride (AdCl), and the exact molecular arrangement of ISA product is obtained from single-crystal analysis. Meanwhile, the amphiphilicity of the complex could be changed by a supramolecular approach using cyclodextin (CD) inclusion, and a thermo-sensitive system is therefore obtained. The high association constants between Ad derivatives andβ-CD (β-cyclodextin) have been reported on the order of 104-105 M"1. The enthalpy-driven and temperature dependent association equilibrium makes it possible for CD inclusions to be thermo-sensitive. The obtained results here have confirmed the expectation thatβ-CD could include Ad blocks and form thermo-sensitive supramolecular inclusions. This three-component superamolecular solution is stable and keeps transparency for more than three months at 5℃. When the temperature was increased from 5 to 25℃or higher, the molecular amphiphilicity is changed via inclusion equilibrium shifting, and another two-component microrods were observed appearing from this three-component solution. Thermo-sensitive supermolecular system is obtained via the cooperation of ISA, cyclodextrin inclusion and other non-covalent interactions, which indicates that various external-stimuli responsive materials could be fabricated based on these non-covalent interactions. In addition, the observed salt effect could be considered in the process of single crystal growth for other ISA systems.Thanks for the supports from the National Natural Science Foundation of China (No.20773080 and 20973104). |
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