基于四丹磺酰胺杯[4]芳烃的汞离子荧光化学传感器

我们方便地合成了上沿修饰四丹磺酰胺基团的杯4]芳烃衍生物1，发现该化合物在含50％水的乙腈中显示出对汞离子高选择性和灵敏性的识别作用，竞争实验表明多数金属离子对其检测干扰较小。机理研究结果表明荧光萃灭源于由丹磺酰胺基团到汞离子的光致电子转移过程。另外，通过研究1和1-Hg2+的荧光衰减实验，以及对比双丹磺酰胺杯4]芳烃2和单丹磺酰胺杯4]芳烃3对汞离子的识别作用，发现化合物1的四丹磺酰胺基团具有很好的预组织和协同作用。化合物1对汞离子的检测限为3.41×10-6 mol·L-1，这可以使1成为一个潜在的汞离子荧光化学传感器。

An Effective Hg2+‐Selective Fluorescent Chemosensor Based on a Calix[4]arene Bearing Four Dansyl Amides

A new calix4]arene‐based fluorescent chemosensor bearing four dansyl amides on the upper rim ( 1 ) was conveniently synthesized, which showed high sensitivity and selectivity toward Hg²⁺ over a wide range of metal ions in 50% aqueous acetonitrile. The complexation of Hg²⁺ ion induced a strong fluorescence quenching of 1 due to a well‐defined electron transfer process from the dansyl group(s) to the metal center. Compared with compounds 2 and 3 , tetradansyl amide substituted calix4]arene 1 showed a preorganized and coordinated complexing site for metal ions. Moreover, the detection limit for Hg²⁺ was found to be 3.41×10^?6 mol·L^?1, which might make 1 a potentially practical Hg²⁺‐selective fluorescent sensor in aqueous system.