Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
Chemistry. 2020 Jun 18;26(34):7595-7601. doi: 10.1002/chem.202001072. Epub 2020 May 19.
We propose post-metalation modification as a useful strategy to control the guest recognition behavior of a metal-containing macrocyclic host. This is based on the ligand exchange of the axial ligands of a cobalt(III) dinuclear macrocyclic host, [LCo X ] (X=axial amine ligand). Four piperidine ligands in [LCo (pip) ] (pip=piperidine) were site-selectively replaced with primary amines. The competitive experiments revealed that the order of the affinity toward the cobalt centers in [LCo X ] is primary amine > secondary amine > tertiary amine and that the piperidine-coordinating complex, [LCo (pip) ] , was reasonably reactive among the isolable complexes. Indeed, two piperidine ligands at the diagonal positions in [LCo (pip) ] were site-selectively replaced with pyridine or acetate ion. The replacement of piperidine with acetate ion significantly enhanced the recognition ability towards Na .
我们提出后配位修饰策略来控制含金属大环主体的客体识别行为。这是基于轴向配体交换钴(III)双核大环主体[LCo X ]（X=轴向胺配体）。[LCo（pip）]（pip=哌啶）中的四个哌啶配体被选择性地用伯胺取代。竞争实验表明，[LCo X ]中钴中心的亲和顺序为伯胺>仲胺>叔胺，可分离配合物中，[LCo（pip）]配合物具有合理的反应活性。事实上，[LCo（pip）]中对角位置的两个哌啶配体被选择性地用吡啶或乙酸根离子取代。用乙酸根离子取代哌啶显著增强了对 Na 的识别能力。
