Mechanically selflocked chiral gemini-catenanes

Mechanically interlocked and entangled molecular architectures represent one of the elaborate topological superstructures engineered at a molecular resolution. Here we report a methodology for fabricating mechanically selflocked molecules (MSMs) through highly efficient one-step amidation of a pseudorotaxane derived from dual functionalized pillar[5] arene (P[5] A) threaded by a, o-diaminoalkane (DA-n; n = 3-12). The monomeric and dimeric pseudo[1] catenanes thus obtained, which are inherently chiral due to the topology of P[5] A used, were isolated and fully characterized by NMR and circular dichroism spectroscopy, X-ray crystallography and DFT calculations. Of particular interest, the dimeric pseudo[1] catenane, named 'gemini-catenane', contained stereoisomeric meso-erythro and dl-threo isomers, in which two P[5] A moieties are threaded by two DA-n chains in topologically different patterns. This access to chiral pseudo[1] catenanes and gemini-catenanes will greatly promote the practical use of such sophisticated chiral architectures in supramolecular and materials science and technology.