对二甲氨基苯甲酸的阴离子识别应用研究

Application of 4-dimethylaminobenzoic acid for anion recognition

采用紫外分光光度法和荧光分光光度法研究了主体分子对二甲氨基苯甲酸与HPO42-、SO42-、H2PO4-、ClO4-、HSO4-、NO3-、BF4-、PF6-、F-、Cl-和Br-等11种阴离子客体的识别作用。发现在乙腈溶液中,该主体分子对二价阴离子HPO42-和SO42-表现了强亲和力和高选择性;并对一价阴离子F-和H2PO4-具有一定的响应能力;而与一价阴离子ClO4-、HSO4-、NO3-、BF4-、PF6-、Cl-和Br-几乎没有作用。结果表明主客体分子本身的酸碱性和阴离子的负电荷数目是影响主体分子对阴离子识别性能的主要因素。

The recognition of 4-dimethylaminobenzoic acid as new class of anion receptors upon complexation with a variety of divalent and monovalent anions was investigated by means of UV-vis and fluorescence spectroscopic studies. As a result,the host in CH3 CN exhibited stronger affinities and higher binding selectivity toward HPO4^2-and SO4^2-over monovalent anions, such as H2 PO4^-, ClO4^-, HSO4^-, NO3^-, BF4^-, PF6^-, F^-,Cl^- and Br^-. Not only the acidity of host and basicity of guests but also the negative charges of anions played a crucial role in affecting the affinity and selectivity of host with anions.