Preparation And Modulation Of Chiral Assembly Based On Perylene-amino Acid Derivatives

Chirality is a basic character of nature and appears at various hicrarchical levels from molecular to supramolecular levels.Supramolecular chirality,which can be simply regarded as chirality at a supramolecular level,is the result of molecular self-assembly.Supramolecular self-assembly is the effective strategy for the preparation of the nano-materials with special structures and excellent properties.Supramolecular chirality attracts so much attention due to their potential applications.The supramolecular chirality has been found to be beneficial in chiral templates,chiral switches,chiral catalysis and chiral liquid crystals.Amino acid is the basic unit of protein.It is an essential nutrient in life system.It is of great significance for understanding structure and properties of proteins if we can reveal the character of chiral assembly of amino acid.In this dissertation,firstly,a series of Perylene-amino acid covalently compounds are designed,synthesized and characterized based on organic conjugated molecules as nucleus.Secondly,the effect of solvent on self-assembly of perylene-amino acid covalent compounds were studies systematically.In addition,the effects of different side groups of amino acids on self-assembly behavior of perylene-amino acid covalent compounds were investigated.Finally,the regulation of water and guest molecules on self-assembly of perylene-amino acid covalent compounds is studied in detail.The main contents are as follows:(1)Modulation of Self-assembly behavior of perylene-phenylalanine by solventThe self-assembled structures of PBI-Phe molecules in ethanol/water,tetrahydrofuran/water,dimethyl sulfoxide/water and N,N-Dimethylformamide/water were studied.The self-assembly of PBI-Phe molecules were controlled by changing the solvent polarity and the proportion.The chiral characteristics of PBI-Phe molecules in self-assemble process were studied by circular dichroism spectroscopy.(2)Study self-assembly morphologies and supramolecular chiral of perylene amino acid covalent compoundsThe different covalently linked Perylene-amino acid conjugated d erivatives have been synthesized based on perylene-3,4,9,10-tetracarboxylic dianhydride and L-amino acid as raw materials.The effects of different amino acid side groups on the assembly structure of peryleneamino acid covalent compounds were studied.The chiral characteristics of Perylene-amino acid conjugated derivatives in self-assemble process was studied by circular dichroism spectroscopy.(3)Water-induced the expression of supramolecular chirality for perylene phenylalanineThe self-assembly based on chiral amino acid derivatives in solutions of DMSO/water with various ratios of these components were investigated.We have unexpectedly found the PBI-Phe molecule to form a spherical structure in pure DMSO,but a helical fiber structure in DMSO/water.The mechanism of water induced supramolecular chiral expression was explored,and the selfassembly arrangement of PBI-Phe molecules was revealed at the single molecular level by STM.(4)Study on the Co-assembly of 4,4'-Azopyridine/ perylene phenylalanineThe coassembly of PBI-Phe molecule and 4,4'-azopyridine were studied.There is no noncovalent bond interaction between the two kinds of molecules in pure DMSO.But the hydrogen bonds are formed between the two kinds of molecules in DMSO/water.The structure morphology was observed by AFM and SEM and the mechanism of coassembly was explored by UV?FT-IR?fluorescence?Circular dichroism and STM.