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Supramolecular assemblies of a nitrogen-embedded buckybowl dimer with C60.

ABSTRACT: A directly connected azabuckybowl dimer was synthesized via a palladium-catalysed C-H/C-Br coupling. The electron-donating nature of the pyrrolic nitrogen atoms of the azabuckybowl enabled a strong complexation with pristine C60. In the presence of two equivalents of C60, the azabuckybowl dimer formed crystals with a 1?:?2 stoichiometry. Conversely, in diluted solution, complexes with a 1?:?1 stoichiometry of the dimer and C60 were detected predominantly, and these precipitated upon increasing the concentration of C60. Scanning electron microscopy images of the precipitate showed fibre-like aggregates, indicating the formation of supramolecular assemblies with 1D chain structures. A variable-temperature 1H NMR analysis revealed that the precipitate consists of the dimer and C60 in a 1?:?1 ratio.

SUBMITTER: Yokoi H

PROVIDER: S-EPMC5872494 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Supramolecular assemblies of a nitrogen-embedded buckybowl dimer with C60.

Yokoi Hiroki H Hiroto Satoru S Sakamaki Daisuke D Seki Shu S Shinokubo Hiroshi H

Chemical science 20171121 4

A directly connected azabuckybowl dimer was synthesized via a palladium-catalysed C-H/C-Br coupling. The electron-donating nature of the pyrrolic nitrogen atoms of the azabuckybowl enabled a strong complexation with pristine C60. In the presence of two equivalents of C60, the azabuckybowl dimer formed crystals with a 1 : 2 stoichiometry. Conversely, in diluted solution, complexes with a 1 : 1 stoichiometry of the dimer and C60 were detected predominantly, ...[more]

PMID: 29629149

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