Selective Construction of Molecular Borromean Rings and [2]Catenane Utilizing Ether Bipyridyl Ligands

Abstract A series of Cp * Rh‐based discrete architectures was constructed by selecting four ether bipyridyl ligands and three half‐sandwich rhodium(III) bimetallic construction units, respectively. This study demonstrates a strategy for making the transition from a binuclear D‐shaped ring to a tetranuclear [2]catenane by adjusting the length of bipyridyl ligands. In addition, changing the position on the naphthyl group of the bipyridyl ligand from 2,6‐ to 1,5‐position substitution can realize the selective synthesis of [2]catenane and Borromean rings under similar conditions. The above‐mentioned constructions have been determined via X‐ray crystallographic analysis, detailed NMR techniques, electrospray ionization‐time‐of‐flight/mass spectrometry analysis, and elemental analysis.