季戊四醇衍生的咪唑鎓化合物的合成及其对阴离子的光谱响应

咪唑鎓本身带有正电荷,2-位碳氢(C2-H)具有一定的酸性,是一种良好的氢键供体,能与阴离子形成氢键。因此,咪唑鎓可以识别各种无机阴离子和生物体内重要的阴离子。本文利用四(1-咪唑甲基)甲烷的独特结构,通过烷基化反应,合成了多咪唑鎓盐2、含有多功能臂的双咪唑鎓盐3和咪唑鎓环番4。采用荧光发射光谱法研究了咪唑鎓盐2、3、4对阴离子(Cl~-、Br~-、I~-、CH_3COO~-、PhCOO~-、HSO_4~-)的光谱响应。结果表明,咪唑鎓盐2和咪唑鎓环番4a加入Cl~-,荧光强度明显增强;咪唑鎓盐3a加入PhCOO~-,荧光强度明显减弱;咪唑鎓盐3b和咪唑鎓环番4b加入I~-,荧光强度明显增强。

Syntheses of Pentaerythritol Derived Imidazolium Compounds and Their Spectral Response to Anions

The imidazolium group is an attractive building block for anion receptors because in contributes a positive charge and relatively acidic C2-hydrogen. By the use of tetra(1-imidazolylmethyl) methane 1, we designed a series of novel imidazoliums with alkylating reagents, including imidazolium 2, the open chain bis-imidazolium salt 3, imidazolium cyclophane 4. The spectral response of compound 2, 3, 4 to anion was further determined by fluorescence spectra. The results showed that imidazolium 2 and imidazolium cyclophane 4a have a better selectivity for Cl-, bisimidazolium 3a has definite recognition ability to PhCOO-, bisimidazolium 3b and imidazolium cyclophane 4b have a better selectivity for I-.