One‐Step Directed Self‐Assembly of Molecular Closed Four‐Link Chains and Borromean Links

Abstract

Abstract Despite substantial advancements in the synthesis of mechanically interlocked molecules (MIMs), the efficient construction of higher order links remains a formidable challenge. Herein, we report the highly efficient one‐step directed construction of a series of unprecedented molecular closed four‐link chains (84 1 metalla‐links), achieved through the synergistic assembly of coordination‐driven and aromatic stacking interactions involving binuclear rhodium/iridium precursors and bis‐dentate benzothiadiazole derivative ligands. Meanwhile, modulating the substituent positions of the pyridine groups in the ligand resulted in a change in topological structure, leading to the formation of two molecular Borromean links ( metalla‐links). The molecular configurations of the abovementioned metalla‐links were clearly identified through mass spectrometry, NMR, and single‐crystal X‐ray diffraction. Furthermore, structural transformation between the molecular Borromean links and corresponding monocycles was achieved through concentration effects, as validated by solution‐state NMR spectroscopy investigations.