Towards the Design and Synthesis of Organic Cage Rotaxanes

机械联锁分子，如轮烷，索烃，和结，已被广泛研究多年。在这些分子中，轮烷是最常见的类型之一-它们由一个大环组成，包含一个称为轴的哑铃形组件，它们通过机械键结合在一起。这允许各个部件以旋转（自旋）和平移（穿梭）运动的形式相对自由地运动。它们的流行导致了功能材料的设计和合成，如笼基轮烷、轮环十六烷、聚轮烷和轮烷树枝状聚合物。在这些材料中，很少有人利用笼（多孔和非多孔）作为轮烷的核心结构单元。相比之下，对多孔有机笼的研究已经导致发现了几种连锁笼结构，通常由预形成的笼的重结晶形成。多孔有机笼是形状持久的微孔结构，其通常由两种或更多种离散的多主题前体的自组装形成，导致形成永久的客人可进入的空腔。该项目旨在通过研究涉及有机笼作为构建块的[n]轮烷的合成，将多孔有机笼和轮烷的化学联合收割机结合起来，这些有机笼将用作轮烷结构中的塞子和/或核心单元。这两种物质结合形成有机笼轮烷可能会导致具有高级功能的材料，例如增加催化或分离分子的位点数量。

Mechanically interlocked molecules, such as rotaxanes, catenanes, and knots, have been extensively studied for many years. Of these molecules, rotaxanes are one of the most common types - these consist of a macrocycle encompassing a dumbbell-shaped component called the axle, which are held together by a mechanical bond. This allows for the relatively free movement of individual components in the form of rotational (pirouetting) and translational (shuttling) movements. Their popularity has led to the design and synthesis of functional materials such as cage-based rotaxanes, rotacatenanes, polyrotaxanes, and rotaxane dendrimers. Of these materials, very little has been done to exploit the use of cages, both porous and non-porous, as core building blocks in rotaxanes. In contrast, studies on porous organic cages have led to the discovery of several catenated cage structures, commonly formed by the recrystallisation of pre-formed cages. Porous organic cages are shape-persistent, microporous structures that typically form from the self-assembly of two or more discrete multi-topic precursors, resulting in the formation of a permanent, guest-accessible cavity. This project aims to combine the chemistry of porous organic cages and rotaxanes by investigating the synthesis of [n]rotaxanes involving organic cages as building blocks, which would either be used as stoppers and/or core units in the rotaxane structure. The combination of these two species to form organic cage rotaxanes could lead to materials with advanced functionality, such as an increase in the number of sites for catalysis or separation of molecules.