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Hierarchical Assembly of an Interlocked M₈ L₁₆ Container.

ABSTRACT: The self-assembly of eight Pd^II cations and sixteen phenanthrene-derived bridging ligands with 60° bite angles yielded a novel M₈ L₁₆ metallosupramolecular architecture composed of two interlocked D_4h -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 M₃ L₆ and M₄ L₈ assemblies formed in the presence of BF₄^- anions into the same interlocked molecule. Furthermore, the densely packed structure of the M₈ L₁₆ catenane was exploited in the preparation of a hexyloxy-functionalized analogue, which further self-assembled into vesicle-like aggregates in a reversible manner.

SUBMITTER: Bloch WM

PROVIDER: S-EPMC5947565 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Hierarchical Assembly of an Interlocked M8 L16 Container.

Bloch Witold M WM Holstein Julian J JJ Dittrich Birger B Hiller Wolf W Clever Guido H GH

Angewandte Chemie (International ed. in English) 20180322 19

The self-assembly of eight PdII cations and sixteen phenanthrene-derived bridging ligands with 60° bite angles yielded a novel M8 L16 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- a ...[more]

PMID: 29392809

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