| Crown ethers, the first generation of supramolecular hosts, have been widely used as building blocks to construct various functional assemblies with guest for the well blanced between hydrosoluble and liposoluble. N-lariat ether as a flexible cavity, several reactable positions and multi-functional sidearms, have attracted considerable attentions. These compounds have been designed for luminescence emission, anion receptors, DNA-cleavage, anion sensors, fluorescence properties, recognition of amino acids and the photochemical molecular devices.Host-guest systems as the good building blocks to assemble the functional supramolecular structure, play an important role in the development of advanced supramolecular structure with the good selectivity, high efficiency responsiveness. Our group have devoted more than ten years to the study of self-assembly of calixarenes. The effects of substituents in the calixarene host-guest supramolecular were analyzed and summarized. The selective modification of the substituents in N-lariat ether also can be used to control the self-assembly of lariat ether, by changing the types, spatial location, orientation of lone pair electrons in N atom and the substituents. In this paper N-lariat ether macrocyclic as hosts, regulation by pendent arm and different supramolecular structure with the molecular channels were studied.In chapter one, the survey of crown ether chemistry was briefly introduced. The conformation of N-lariat ether, the structures of crown ether scaffold with different types, spatial location and orientation of the substituents were reviewed. The various applications of N-lariat ether with respective functions, and the effects of substituents on the host-guest behavior were analyzed and summarized. In light of the above introduction, the design strategies of this thesis outlined.In chapter two, several types of di-sidearm N-lariat ether derivatives and mono-sidearm N-lariat ether derivatives with flexible sidearm were synthesized. The molecular structures were characterized by X-ray, NMR and ESI-MS. The influence of the crystallization medium (solvent), and the sidearm on the self-assembly of di-siderarm N-lariat ether derivatives with semi-rigid crown ether skeleton bearing flexible substituents and the formation of these compounds in crystal were studied.In chapter three, the influence of the sidearm quantity, oriention and structure on the self-assembly of terephthalic acid and N-lariat ether derivatives with semi-rigid crown ether skeleton bearing flexible substituents and the formation of these complexes in crystal were studied. Under the same crystallization condition, macrocycle bearing different structures or numbers of pendant arm with similar pKa, shows different ionization properties. This consistent with the fact the proton transfer depends also upon the solid state environment. X-ray studies for the exocyclic behaviors by N,N'-disubstituented dibenzo-diaza-crown ethers, but endo-coordinated water structures by N-substituted dibenzo-aza-crown ethers with same condition, reveal that the importance of competitive hydrogen bonding in the supramolecular self-assembly. The head-to-head arrangement of 1,4-dicarboxybenzene via O-H…N hydrogen bonding as the robust supramolecular motif is preserved in the exocyclic supramolecular structures by the'out-out' di-sidearm DBDA18C6s. But a series of layered structures were obtained by mono-sidearm DBA18C6s, with the sheet of protonated crown ether inclusions are sandwiched between solvated PTA anion layers and self-assembly of the ion pairs is not governed by strong and directional hydrogen-bonding interactions as well as stronger and not so-directional electrostatic interactions between the cations and anions. Moreover, the length of side chain arm may introduce minor crystal structure disparity in di-sidearm crown ether complexes, particularly 3-D packing types with herringbone-type via aromatic CH/? hydrogen bond, but parallel packing with ?…? interaction. The conformations of mono-sidearm crown ether in the salts were influenced by the side chain chemical composition and molecular structure more than the side chain length.In chapter four, the self-assembly behavior of N-lariat ether derivatives with different guest and also the the influence of the sidearm and the crystallization medium (guest type) have both studied. X-ray studies for the exocyclic behaviors by N,N'-disubstituented dibenzo-diaza-crown ethers-pyromellitic acid complexes, and endo-coordinated water structures by N,N'-disubstituented dibenzo-diaza-crown ethers-picric acid complex with same conditions, also reveal that the importance of competitive hydrogen bonding in the supramolecular self-assembly. The water channel in N,N'-disubstituented dibenzo-diaza-crown ethers-picric acid complex was assembled by the O-H…O hydrogen bond between water in crown and CA, as well as the ?…? interactions between parall CA and benzene in crown ether. The length of side chain arm may introduce crystal structure disparity in di-sidearm crown ether-pyromellitic acid complexes. A water channel structures were obtained by mono-sidearm DBA18C6-picric acid complex, with protonated crown ether inclusions are connected between C-H-…?, C-H…O and ?…? interactions. Moreover, the length of side chain arm may introduce huge crystal structure disparity in sidearm crown ether complexes result by the competitive hydrogen bonding in the supramolecular self-assembly. The conformations of mono-sidearm crown ether in the salts were influenced by the side chain chemical composition and molecular structure more than the side chain length. The solvent molecular would benefit to the assembly of N-lariat ether-guest complexes, as the solvent enters the nanotube which build by the assembly of 2-D structure and influenced by length of sidearm and participate in the assembly of 3-D structure. And the Di-siderarm N-lariat ether bearing the CH2-CH=CH2 coordinate the AgPic by Ag…N and Ag…? interactions, weakens Ag…O interaction as the semi-rigid skeleton crown. |
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