调谐的 Cd 选择性：π-扩展二-2-吡啶基胺取代喹啉基 Tolans 的电子和区域效应的展示。

Tuned Cd Selectivity: Showcase of Electronic and Regio-Effect of π-Extended Di-2-Picolylamine-Substituted Quinoline-Based Tolans.

机构信息

Department of Chemistry and Chemical Engineering, Inha University, Inharo 100, Nam-gu, Incheon 22212, Korea.

出版信息

Molecules. 2021 Feb 9;26(4):917. doi: 10.3390/molecules26040917.

π-Extended di-2-picolylamine (DPA)-substituted 8-hydroxyquinoline (8-HQ) tolans () were synthesized for testing electronic and regio-effects. The electron-poor CN-tolan () showed clear selectivity for Cd (>>Zn) over other metal ions via turn-on fluorescence, while the electron-rich MeO-tolan () displayed no clear metal selectivity. Furthermore, considering that there was no significant energy difference between the Cd complexes of and , the intended regio-effect (7- vs. 5-substituted effect) did not induce steric hindrance. Thus, the regio-effect is mainly electronic. Considering the above, and constitute a complete showcase in which electronic and regio-effects modulate the metal selectivity. The fluorescence titration of (10 mM) with Cd showed that the limit of detection (LOD) of the Cd-selective was 158 nM in PBS (phosphate-buffered saline) (10 mM, pH 7.2) containing 50% MeOH.

π-扩展的二-2-吡啶基胺（DPA）取代的 8-羟基喹啉（8-HQ）托兰（）被合成以测试电子和区域效应。缺电子的 CN-托兰（）通过开启荧光显示出对 Cd（>>Zn）相对于其他金属离子的明显选择性，而富电子的 MeO-托兰（）则没有显示出明显的金属选择性。此外，考虑到和的 Cd 配合物之间没有明显的能量差异，预期的区域效应（7-取代与 5-取代效应）不会引起空间位阻。因此，区域效应主要是电子的。考虑到上述情况，和构成了一个完整的范例，其中电子和区域效应调节金属选择性。用 Cd 对（10 mM）进行荧光滴定表明，Cd 选择性的的检测限（LOD）在 PBS（磷酸盐缓冲盐水）（10 mM，pH 7.2）中含有 50% MeOH 时为 158 nM。