| Currently the chiral surfactants have been gradually found with regioselectivity, chiral catalysis and chiral recognition character, therefore they cause more attention in these areas of chiral synthesis and application of chiral recognition. Amino acid surfactants are a kind of important biological compatibility agent which have amino acids or short peptide as a hydrophilic head. They possess chiral molecular structures and can be formed chiral micelle and one dimensional helical structure in the solution. However, on the one-dimensional forming properties of chiral self-assembly, and based on the chiral features used for preparation of chiral nanomaterials were rare reported. There we synthesized a series of chiral amino acid surfactants based alanine amino and studied one-dimensional chiral self-assembly synthesis and adjustment mechanisms in solution. Also, we applied them to the induction of metal oxide nanomaterials preparation, Then it provide an important theoretical basis.1. Three chiral surfactants C12Ala, C8Ala, C4Ala were synthesized via one-step in this paper. All of these surfactants were characterized by ultimate analysis,1H NMR, FT-IR, melting point method, elemental analysis, suggesting that these surfactants are of high purity. In addition, the micelle behavior of these surfactants in aqueous solution was studied through surface tension and fluorescent spectrometry. For C12Ala, surface tension showed two turning points, corresponding to cac (0.2 mmol/L) and cmc (1.8 mmol/L) respectively, consistent with that proved by fluorescent spectrometry. As the chain length decreases, the cncs increase from 1.8 mmol/L to 100.0 mmol/L. Among these surfactants, C12Ala has the highest surface activity with the γcmc being 35.9 mN/m while that of the other two surfactants are not good due to the reduction of chain length.2. The aggregation behavior of N-(2-Hydroxydodecyl) alanine in aqueous solution and the effect of solution concentration, temperature, pH on C12Ala have been investigated by using dynamic light scattering (DLS), transmission electron microscopy (TEM),1H nuclear magnetic resonance (NMR), circular dichroism spectroscopy (CD) measurements. It was found that it is in a single molecule state when the concentration of surfactant is less than 0.2 mmol/L, with the increase of the surfactant concentration (<1.0mmol/L), the structure of the aggregates is spherical micelles and the diameter is about 20 nm;when the concentration up to 1.0 mmol/L, the aggregates transform into the one-dimensional helical structure, the length is about 7μm, the width is about 17 nm. With the increase of the temperature at the solution concentration of 8.0 mmol/L, spiral structure become shorter, and be contracted; the spiral structure is destroyed gradually with the pH changed, transforming into the hollow structure change, dynamic light scattering further verify the above results. As can be seen from the CD, there are intensity increase in positive band with the increase of concentration, the peak position was unchanged, which showed that the structure of the chiral self assembly was unchanged, but its spatial accumulation mode changed. According to the spectrum analysis of 1H NMR and 2D NOESY, it was indicated that the molecular has been distorted and folded in the process of aggregation, which leads to the appearance of the asymmetric spiral structure. Therefore, the structure and property of chiral aggregates can be regulated by adjusting the concentration, temperature and pH of the solution.3. We synthesized CuO micro-nano materials based on chiral characteristics of C12Ala and characterized the CuO micro-nano structure via the scanning electron microscopy (SEM), X-ray diffraction, FT-IR. Research shows that the concentration of the C12Ala for 0.1 mmol/L, CuO structure (major axis is about 3μm and minor axis is about 1.5μm) can be flake. With the increase of concentration it turns to spherical flower-like. When the chain length is same, the non-chiral ionic surfactant sodium dodecyl sulfate (SDS) and dodecyl trimethyl ammonium bromide (DTAB) inducing CuO micro-nano materials only get lamellar structure. When the molar ratio of C12Ala and CuCl2 is 2:1, it only can get flower-like asymmetric structure. Temperature measurement show that at 120℃, it can obtain the flower shape asymmetry structure.The above are monoclinic crystal CuO. FT-IR spectra showed that the coordination effect of the hydroxyl in C12Ala and Cu2+ is the key function in inducing flower-like CuO asymmetric structure. The structures above provide a new way of preparation of metal nano-materials.
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