The sterically shielded terpyridine 5 was prepared, both as a new ligand and as part of the four-station nanoscaffold 2. Mixing of terpyridine 5, the parent phenanthroline 4 and the shielded phenanthroline 3 in the presence of Zn2+ (1 : 1 : 1 : 1) furnished quantitatively the inverse HETTAP complex [Zn(4)(5)]2+ by self-sorting, while in the presence of Cu+ the HETPHEN complex [Cu(3)(4)]+ was preferred (89%). Due to the akin coordination preferences of Cu2+ and Zn2+, the above self-sorting was implemented for Cu+/Cu2+ on nanoscaffold 2, the latter equipped with the binding motifs of 3 (PhenAr2) and 5 (TerpyAr2). When 2 was reacted with Cu+ and phenanthroline (4) in a 1 : 2 : 2 ratio, only the PhenAr2 stations became involved in complex formation (= Cu1phen). In contrast, upon oxidative formation of Cu2+, ligand 4 was exclusively moved to the TerpyAr2 stations (Cu1terpy). Electrochemical oxidation–reduction prompted the cargo to be shipped reversibly on a subsecond time scale between the two different stations of 2.
我们制备了立体屏蔽的萜
吡啶 5,它既是一种新
配体,也是四站纳米支架 2 的一部分。在 Zn2+ 存在下(1:1:1:1:1),将萜
吡啶 5、母体
菲罗啉 4 和屏蔽
菲罗啉 3 混合,通过自排序定量生成反向 HE
TTAP 复合物 [Zn(4)(5)]2+,而在 Cu+ 存在下,HETPHEN 复合物 [Cu(3)(4)]+ 更受青睐(89%)。由于 Cu2+ 和 Zn2+ 具有相似的配位偏好,因此在纳米支架 2 上对 Cu+/Cu2+ 进行了上述自排序,后者配备了 3(PhenAr2)和 5(TerpyAr2)的结合基团。当 2 以 1 : 2 : 2 的比例与 Cu+ 和
菲罗啉(4)反应时,只有 PhenAr2 站参与了络合物的形成(= Cu1phen)。相反,在 Cu2+ 氧化形成时,
配体 4 只移动到 TerpyAr2 位置(Cu1terpy)。电
化学氧化还原促使货物在亚秒级的时间内可逆地在 2 的两个不同站之间运输。