Abstract:

A novel heteroatomic alkyl chain compound 1 with bis-benzothiazole groups was synthesized facilely by nucleophilic substitution reaction using N-phenyldiethanolamine and 2-mercapto benzothiazole as raw materials, and its structure was characterized by ¹H NMR, ¹³C NMR and elemental analysis. The spectral changes of compound 1 with many metal cations (Mn²⁺、Co²⁺、Cu²⁺、Zn²⁺、Ni²⁺、Fe³⁺、 Hg²⁺、Cr³⁺、Al³⁺) had been investigated by the UV-vis spectrophotometry, and the recognition performance of filter papers treated by compound 1 with many metal cations in aqueous solution was explored, finally the mechanism of forming complexes with metal cations was discussed by ¹H NMR. It was found that the color of solution of compound 1 in acetonitrile was changed to brown after adding Cu²⁺, which was obviously different from adding other cations; the special filter paper will become yellow when it encounters Cu²⁺ in aqueous solution, and no color change was observed in case of other cations. The results showed that compound 1 only exhibited the selective recognition to Cu²⁺ and it could be clearly detected by our naked eyes. In a word, compound 1 is a highly efficient and simple probe for Cu²⁺.

Key words: copper (Ⅱ) ion, recognition, visible probe, molecular synthesis, NMR, complexes

摘要：

以N-苯基二乙醇胺和2-巯基苯并噻唑为原料通过亲核取代反应合成了一种新型的苯并噻唑基修饰的开链冠醚类化合物1，并用核磁共振氢谱, 核磁共振碳谱及元素分析方法对合成产物进行了表征。利用紫外光谱仪考察了化合物1与多种金属离子（Mn²⁺、Co²⁺、Cu²⁺、Zn²⁺、Ni²⁺ 、Fe³⁺、 Hg²⁺、Cr³⁺、Al³⁺）在乙腈溶液中的光谱变化，并探究了化合物1处理过的滤纸条在水溶液中对金属离子的识别效果，通过核磁共振氢谱讨论了化合物1与金属离子形成配合物的作用机理。实验发现，化合物1的乙腈溶液中添加Cu²⁺后溶液颜色变为棕色，明显区别于添加其他离子；在水溶液中，特制的滤纸条遇到Cu²⁺会呈现黄色，而遇其他离子均无颜色变化。结果表明，化合物1仅对Cu²⁺具有选择性，且能通过裸眼进行识别，是一种高效、简便的Cu²⁺探针。

关键词: 二价铜离子, 识别, 可见探针, 分子合成, 核磁共振, 配合物