Chiral Truxene‐Based Self‐Assembled Cages: Triple Interlocking and Supramolecular Chirogenesis

Abstract

Incorporating chiral elements in host‐guest systems currently focuses much attention, which results from the major impact such structures may have onto a wide range of applications, from pharmaceuticals to materials science and beyond. Moreover, the development of multi‐responsive and ‐functional systems is highly desirable since they offer numerous benefits. In this context, we describe herein the construction of a metal‐driven self‐assembled cage that associates a chiral truxene‐based ligand and a bis‐ruthenium complex. The maximum separation between both facing chiral units in the assembly is fixed by the intermetallic distance within the lateral bis‐ruthenium complex (8.4 Å). The resulting chiral cavity was shown to encapsulate polyaromatic guest molecules, but also to afford a chiral triply interlocked [2]catenane structure. The formation of the latter occurs at high concentration, while its disassembly could be achieved by addition of a planar achiral molecule. Interestingly the latter exhibits induced circular dichroism signature when trapped within the chiral cavity, demonstrating the cage ability for inducing supramolecular chirogenesis.