Polymers with all mechanically interlocked rings, such as linear [n]catenanes, have great potential as functional materials due to possible higher degrees of freedom that may contribute to their flexibility but remain elusive. All the synthetic methods used to prepare such a polymer yield mixtures of products. In the absence of higher molecular weight linear [n]catenanes, emphasis on synthesizing low molecular weight oligomers is being pursued. Here, we have described the synthesis of a linear [5]catenane by post‐functionalizing a Co(III) templated [2]catenane having a pyridine‐diamide unit free for further metal ion coordination. Two molecules were synthesized with suitable threading groups: one, two terminal azide groups, and two, with two terminal alkyne groups to form two [3]pseudorotaxane utilizing Co(III) coordination. These units were then joined, forming a macrocycle, using click reaction, giving the desired metallated linear [5]catenane in 40% yield. Removal of metal ions leads to linear [5]catenane. In addition, the formation of linear [3] and [2]catenane are also observed. All synthesized structures have been isolated by column chromatographic technique and characterized by 1H‐NMR, 13C‐NMR, and mass spectroscopy.

中文翻译：

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通过模板化 [2] 索烯的后官能化和点击反应，模板辅助合成线性 [5] 索烯

具有所有机械互锁环的聚合物，例如直链[n]链烷，由于可能具有更高的自由度，因此具有作为功能材料的巨大潜力，这可能有助于其灵活性，但仍然难以捉摸。用于制备这种聚合物的所有合成方法都会产生产物的混合物。在缺乏较高分子量的直链[n]链烷的情况下，人们正在致力于合成低分子量低聚物。在这里，我们描述了通过对具有吡啶-二酰胺单元的Co(III)模板[2]链烯进行后官能化来合成直链[5]链烯，该[2]链烯具有游离的吡啶-二酰胺单元，可用于进一步的金属离子配位。合成了具有合适螺纹基团的两个分子：一个具有两个末端叠氮基团，以及两个具有两个末端炔基基团以利用Co(III)配位形成两个[3]假轮烷。然后使用点击反应将这些单元连接起来，形成大环，得到所需的金属化直链[5]链烯，产率为 40%。金属离子的去除产生直链[5]链烯。此外，还观察到线性[3]和[2]链烯的形成。所有合成的结构均通过柱色谱技术分离，并通过 1H-NMR、13C-NMR 和质谱进行表征。