Stimuli-responsive mechanically interlocked molecules constructed from cucurbit[]uril homologues and derivatives.

Cucurbit[]uril supramolecular chemistry has developed rapidly since 2001 when different cucurbit[]uril homologues (Q[]) were successfully separated in pure form. The combination of Q[] cavity size and various types of external stimuli has given birth to numerous types of Q[]-based mechanically interlocked molecules (MIMs), including (pseudo)rotaxanes, catenanes, dendrimers and poly(pseudo)rotaxanes. In this review article, the important advances in the field of Q[]-based MIMs over the past two decades are highlighted. This review also describes examples of heterowheel (pseudo)rotaxanes and poly(pseudo)rotaxanes involving Q[]s, and reflects on the opportunities and challenges of constructing Q[]-based stimuli-responsive MIMs.