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A Halogen-Bond-Induced Triple Helicate Encapsulates Iodide.

ABSTRACT: The self-assembly of higher-order anion helicates in solution remains an elusive goal. Herein, we present the first triple helicate to encapsulate iodide in organic and aqueous media as well as the solid state. The triple helicate self-assembles from three tricationic arylethynyl strands and resembles a tubular anion channel lined with nine halogen bond donors. Eight strong iodine???iodide halogen bonds and numerous buried ?-surfaces endow the triplex with remarkable stability, even at elevated temperatures. We suggest that the natural rise of a single-strand helix renders its linear halogen-bond donors non-convergent. Thus, the stringent linearity of halogen bonding is a powerful tool for the synthesis of multi-strand anion helicates.

SUBMITTER: Massena CJ

PROVIDER: S-EPMC5155591 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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A Halogen-Bond-Induced Triple Helicate Encapsulates Iodide.

Massena Casey J CJ Wageling Nicholas B NB Decato Daniel A DA Martin Rodriguez Enrique E Rose Ariana M AM Berryman Orion B OB

Angewandte Chemie (International ed. in English) 20160714 40

The self-assembly of higher-order anion helicates in solution remains an elusive goal. Herein, we present the first triple helicate to encapsulate iodide in organic and aqueous media as well as the solid state. The triple helicate self-assembles from three tricationic arylethynyl strands and resembles a tubular anion channel lined with nine halogen bond donors. Eight strong iodine⋅⋅⋅iodide halogen bonds and numerous buried π-surfaces endow the triplex with remarkable stability, even at elevated ...[more]

PMID: 27411932

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The Halogen Bond.

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Project description:We report a strategy to achieve a discrete cage molecule featuring a high level of structural hierarchy through a multiple-assembly process. A cobalt (Co) supramolecular triple-stranded helicate (Co-TSH)-based discrete molecular cage (1) is successfully synthesized and fully characterized. The solid-state structure of 1 shows that it is composed of six triple-stranded helicates interconnected by four linking cobalt species. This is an unusual example of a highly symmetric cage architecture resulting from the coordination-driven assembly of metallosupramolecular modules. The molecular cage 1 shows much higher CO2 uptake properties and selectivity compared with the separate supramolecular modules (Co-TSH, complex 2) and other molecular platforms.

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Stabilizing Halogen-Bonded Complex between Metallic Anion and Iodide.

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