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Anion-driven encapsulation of cationic guests inside pyridine[4]arene dimers.

ABSTRACT: Pyridine[4]arenes have previously been considered as anion binding hosts due to the electron-poor nature of the pyridine ring. Herein, we demonstrate the encapsulation of Me4N+ cations inside a dimeric hydrogen-bonded pyridine[4]arene capsule, which contradicts with earlier assumptions. The complexation of a cationic guest inside the pyridine[4]arene dimer has been detected and studied by multiple gas-phase techniques, ESI-QTOF-MS, IRMPD, and DT-IMMS experiments, as well as DFT calculations. The comparison of classical resorcinarenes with pyridinearenes by MS and NMR experiments reveals clear differences in their host-guest chemistry and implies that cation encapsulation in pyridine[4]arene is an anion-driven process.

SUBMITTER: Kiesila A

PROVIDER: S-EPMC6839556 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Anion-driven encapsulation of cationic guests inside pyridine[4]arene dimers.

Kiesilä Anniina A Moilanen Jani O JO Kruve Anneli A Schalley Christoph A CA Barran Perdita P Kalenius Elina E

Beilstein journal of organic chemistry 20191021

Pyridine[4]arenes have previously been considered as anion binding hosts due to the electron-poor nature of the pyridine ring. Herein, we demonstrate the encapsulation of Me4N+ cations inside a dimeric hydrogen-bonded pyridine[4]arene capsule, which contradicts with earlier assumptions. The complexation of a cationic guest inside the pyridine[4]arene dimer has been detected and studied by multiple gas-phase techniques, ESI-QTOF-MS, IRMPD, and DT-IMMS experiments, as well as ...[more]

PMID: 31728162

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