School of Chemistry, Sun Yat-Sen University, Guangzhou, China.
Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada.
Nat Chem. 2018 Jun;10(6):625-630. doi: 10.1038/s41557-018-0040-9. Epub 2018 Apr 30.
Mechanically interlocked molecules such as rotaxanes and catenanes comprise two or more components whose motion relative to each other can be controlled. A [2]rotaxane molecular shuttle, for example, consists of an axle bearing two recognition sites and a single macrocyclic wheel that can undergo a to-and-fro motion along the axle-shuttling between the recognition sites. The ability of mechanically interlocked molecules to undergo this type of large-amplitude change is the core mechanism behind almost every interlocked molecular switch or machine, including sophisticated mechanical systems such as a molecular elevator and a peptide synthesizer. Here, as a way to expand the scope of dynamics possible at the molecular level, we have developed a molecular shuttling mechanism involving the exchange of rings between two recognition sites in a saturated [3]rotaxane (one with no empty recognition sites). This was accomplished by passing a smaller ring through a larger one, thus achieving ring-through-ring molecular shuttling.
机械互锁分子如轮烷和索烃由两个或多个组件组成，它们之间的相对运动可以被控制。例如，[2]轮烷分子梭由一个轴承载两个识别位点和一个单一的大环轮组成，大环轮可以沿着轴进行往复运动，在识别位点之间穿梭。机械互锁分子能够进行这种大振幅变化的能力是几乎每一个互锁分子开关或机器的核心机制，包括复杂的机械系统，如分子电梯和肽合成器。在这里，作为在分子水平上扩展动态范围的一种方式，我们开发了一种分子穿梭机制，涉及在一个饱和的[3]轮烷（一个没有空识别位点的轮烷）的两个识别位点之间交换环。这是通过将一个较小的环穿过一个较大的环来实现的，从而实现了环穿环的分子穿梭。
