Chiral bis- and multi-macrocycles based on pillararenes

During recent years, taking advantage of the unique dynamic planar chirality of pillararenes, the further introduction of fused rings gives rise to the successful construction of diverse chiral bis- and multi-macrocycles. On the one hand, pillararene-based bis-macrocycles with rotatable sub-rings have proven to be privileged platforms for the construction of novel chiral inversion molecular machines, particularly molecular universal joints (MUJs). On the other hand, the integration of pillararenes with other macrocycles featuring interesting properties or the construction of pillararene-fused giant macrocycles leads to the creation of attractive chiral platforms with excellent properties, particularly circularly polarized luminescence (CPL). To highlight the great potential of these promising chiral functional platforms, in this review, the advancements in research on pillararene-based chiral bis- and multi-macrocycles in recent years will be briefly summarized, focusing on the design strategy, chiral inversion mechanism, and attractive properties.