Hierarchical assembly of an interlocked M8L16 container

Abstract

The self‐assembly of eight PdII cations and sixteen phenanthrene‐derived bridging ligands with 60° bite angles yielded a novel M8L16 metallosupramolecular architecture composed of two interlocked D4h‐symmetric barrel‐shaped containers. Mass spectrometry, NMR spectroscopy, and X‐ray analysis revealed this self‐assembled structure to be a very large “Hopf link” catenane featuring channel‐like cavities, which are occupied by NO3− anions. The importance of the anions as catenation templates became imminent when we observed the nitrate‐triggered structural rearrangement of a mixture of M3L6 and M4L8 assemblies formed in the presence of BF4− anions into the same interlocked molecule. Furthermore, the densely packed structure of the M8L16 catenane was exploited in the preparation of a hexyloxy‐functionalized analogue, which further self‐assembled into vesicle‐like aggregates in a reversible manner.