一种基于硫杂杯[4]芳烃的高效银离子载体

合成了基于下缘含有酰肼基团的硫杂杯芳烃衍生物的银离子载体1，其核磁研究证实硫杂杯芳烃以1,3-交替构象存在，并且通过非竞争萃取实验和竞争萃取实验研究了它对碱金属和过渡金属离子（Li⁺, Na⁺, K⁺, Cs⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺ and Ag⁺）的键合能力和选择性。实验结果表明：将酰肼基团引入1,3-交替构象的硫杂杯芳烃骨架的下缘可以提高其对Ag⁺的键合能力和选择性，同时，对Cu²⁺的萃取能力较弱，对碱金属离子和其它的重金属离子几乎没有萃取能力。进一步的核磁滴定和电喷雾质谱实验显示化合物1与银离子形成配合物的配合计量比为1：1，由此推断主要由“N-Ag⁺”配位键以及硫杂杯芳烃骨架的协同作用构成了化合物1与银离子的配合模式。

An Efficient Ag+ Ionophore Based on Thiacalix[4]arene

A novel Ag⁺ ionophore, p‐tert‐butyl‐tetrakis(hydrazinocarbonylmethoxy)thiacalix4]arene in 1,3‐alternate conformation (thiacalix4]arene tetrahydrazide, 1 ) was synthesized. Its binding properties towards alkali and transition metal cations were studied by noncompetitive liquid‐liquid extraction of alkali metal (Li⁺, Na⁺, K⁺ and Cs⁺) and transition metal (Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Ag⁺) picrates. It was found that the thiacalix4]arene tetrahydrazide exhibited high extractability towards Ag⁺, lower percent extraction towards Cu²⁺, and little or no extraction ability towards the others. The selectivity towards Ag⁺ was further evaluated by competitive Ag⁺ extraction experiments in the mixture of the above‐mentioned nine cations, the concentration of which was monitored with ICP‐OES. ¹H NMR titration experiments and ESI‐MS proved the stoichiometry of 1 to Ag⁺ was 1:1, and the ′N‐Ag⁺′ interaction with the assistance of thiacalixarene skeleton was primarily involved in the complexation.