以連續取代反應合成車輪烷之研究

Abstract

由於主客體結合形成準車輪烷的過程需要許多非共價作用力的共同合作，因此，反應過程或化學試劑中若有諸如強酸強鹼、高極性溶劑或競爭離子的出現，都可能對主客體的結合造成相當不利的影響。因此，迄今僅有少數的化學反應能適用在準車輪烷的封鎖反應上。替代法則可以避開這些反應限制或試劑要求，先藉由特定的封鎖基團合成替代車輪烷、再進行可保持大環內鎖的封鎖基團更換反應。我們認為若能選定好適當的封鎖基團，則不僅能高效地製備目標車輪烷，還能同時將封鎖基團回收再利用，使替代法能夠更加符合分子經濟學。

Because many weak non-covalent interactions are involved in the efficient assembly of pseudorotaxanes, only a few chemical reactions are available for the practical interlocking of pseudorotaxanes. The so-called "surrogate approach" has been developed to bypass the limitations. Sutiable stoppering units are chosen to interlock pseudorotaxanes with high efficiency and then reactions of the stoppering functionalities are performed to replace them with new ones, without dissociation of the interlocked macrocycle. We believe that by selecting appropriate stopper, not only can the target pseudorotaxanes be efficiently synthesized, but the stopper can also be recycled, thereby making the Surrogate approach more economically valuable.