A cyclic bis[2]catenane metallacage
Yiliang Wang, Yicheng Zhang, Zhixuan Zhou, Ryan T. VanderLinden, Bin Li, Bo Song, Xiaopeng Li, Lei Cui, Jian Li, Xueshun Jia, Jianhui Fang, Chunju Li, Peter J. Stang
Abstract
Catenated cages represent chemistry's challenging synthetic targets because a three-dimensional assembly is necessary for their formation. Herein, a cyclic bis[2]catenane is constructed through the coordination-driven self-assembly of the interlocked bis-metallacage, by the 90° Pt(II) heteroligation of the endo-functionalized double-bridged tweezer bearing pyridyl moieties and the tetra-carboxylated linker. NMR spectrometry, X-ray crystallography and mass spectrometry confirm the formation of a cyclic bis[2]catenane with "∞"-shaped topology via a 14-component self-assembly. Particularly, reversibly responsive transformation between the bis[2]catenane and the bis-metallacage can be realized by guest exchange, concentration effect and solvent effect. This work represents a novel example of a cyclic cage-based [2]catenane oligomer.