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Multiple threading of a triple-calix[6]arene host.

ABSTRACT: The synthesis of the triple-calix[6]arene derivative 6 in which three calix[6]arene macrocycles are linked to a central 1,3,5-trimethylbenzene moiety is reported. Derivative 6 is able to give multiple-threading processes in the presence of dialkylammonium axles. The formation of pseudo[2]rotaxane, pseudo[3]rotaxane, and pseudo[4]rotaxane by threading one, two, and three, respectively, calix-wheels of 6 has been studied by 1D and 2D NMR, DOSY, and ESI-FT-ICR MS/MS experiments. The use of a directional alkylbenzylammonium axle led to the stereoselective formation of endo-alkyl pseudo[n]rotaxane stereoisomers.

SUBMITTER: Iuliano V

PROVIDER: S-EPMC6753684 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Multiple threading of a triple-calix[6]arene host.

Iuliano Veronica V Ciao Roberta R Vignola Emanuele E Talotta Carmen C Iannece Patrizia P De Rosa Margherita M Soriente Annunziata A Gaeta Carmine C Neri Placido P

Beilstein journal of organic chemistry 20190903

The synthesis of the triple-calix[6]arene derivative 6 in which three calix[6]arene macrocycles are linked to a central 1,3,5-trimethylbenzene moiety is reported. Derivative 6 is able to give multiple-threading processes in the presence of dialkylammonium axles. The formation of pseudo[2]rotaxane, pseudo[3]rotaxane, and pseudo[4]rotaxane by threading one, two, and three, respectively, calix-wheels of 6 has been studied by 1D and 2D NMR, DOSY, and ESI-FT-ICR MS/MS experiments ...[more]

PMID: 31579081

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