Synthesis and Chiral Recognition Ability of a Poly(phenylenevinylene)-Encapsulated Amylose Derivative
作者:Kazumi Tamura、Nor Syahidah Md Sam、Tomoyuki Ikai、Yoshio Okamoto、Eiji Yashima
DOI:10.1246/bcsj.20110074
日期:2011.7.15
Poly(p-phenylenevinylene) (PPV) was found to be encapsulated in amylose during the polymerization of the precursor monomer in an aqueous solution. The resulting amylose–PPV composite can be further chemically modified by introducing various substituents into the hydroxy groups of the amylose using isocyanates and acetic anhydride. Here we report on the chemical modification of the amylose–PPV composite with 3,5-dimethylphenyl isocyanate in order to obtain a novel chiral packing material for resolving enantiomers by high-performance liquid chromatography (HPLC). The obtained 3,5-dimethylphenylcarbamated amylose–PPV was soluble in pyridine and exhibited a lyotropic liquid crystalline phase in a concentrated pyridine solution. The chiral recognition ability of the 3,5-dimethylphenylcarbamated amylose–PPV was different from that of amylose tris(3,5-dimethylphenylcarbamate) having no PPV rods in the helical cavity of the amylose and can resolve many racemic compounds into enantiomers. Among racemic compounds, cyclic dibenzamide and dibenzanilide derivatives were resolved on the 3,5-dimethylphenylcarbamated amylose–PPV better than amylose tris(3,5-dimethylphenylcarbamate). The difference in the enantioseparation abilities of these amylose-based chiral stationary phases for HPLC is discussed based on the difference in their helical structures.
研究发现,在水溶液中聚合前体单体时,聚对苯二甲酰乙烯(PPV)会被包裹在淀粉中。通过使用异氰酸酯和醋酸酐在淀粉的羟基上引入各种取代基,可以进一步对所得到的淀粉-PPV 复合材料进行化学改性。在此,我们报告了用 3,5-二甲基苯基异氰酸酯对直链淀粉-PPV 复合材料进行化学改性,以获得一种新型手性填料,用于通过高效液相色谱法(HPLC)分辨对映体。得到的 3,5-二甲基苯基氨基甲酸淀粉-PPV 可溶于吡啶,并在浓吡啶溶液中呈现溶胀性液晶相。3,5-二甲苯基氨基甲酸淀粉-PPV 的手性识别能力不同于淀粉螺旋腔中没有 PPV 棒的淀粉三(3,5-二甲苯基氨基甲酸),它能将许多外消旋化合物解析成对映体。在外消旋化合物中,环二苯甲酰胺和二苯甲酰苯胺衍生物在 3,5-二甲苯基氨基甲酸淀粉-PPV 上的解析效果优于三(3,5-二甲苯基氨基甲酸)淀粉。根据螺旋结构的不同,讨论了这些用于高效液相色谱的淀粉基手性固定相在对映体分离能力上的差异。