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Rim-Differentiated C₅-Symmetric Tiara-Pillar[5]arenes.

ABSTRACT: The synthesis of "rim-differentiated" C₅-symmetric pillar[5]arenes, whose two rims are decorated with different chemical functionalities, has remained a challenging task. This is due to the inherent statistical nature of the cyclization of 1,4-disubstituted alkoxybenzenes with different substituents, which leads to four constitutional isomers with only 1/16th being rim-differentiated. Herein, we report a "preoriented" synthetic protocol based on FeCl₃-catalyzed cyclization of asymmetrically substituted 2,5-dialkoxybenzyl alcohols. This yields an unprecedented 55% selectivity of the C₅-symmetric tiara-like pillar[5]arene isomer among four constitutional isomers. Based on this new method, a series of functionalizable tiara-pillar[5]arene derivatives with C₅-symmetry was successfully synthesized, isolated, and fully characterized in the solid state.

SUBMITTER: Guo M

PROVIDER: S-EPMC5765533 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Rim-Differentiated C5-Symmetric Tiara-Pillar[5]arenes.

Guo Minjie M Wang Xuemei X Zhan Caihong C Demay-Drouhard Paul P Li Wenjiao W Du Ke K Olson Mark A MA Zuilhof Han H Sue Andrew C-H AC

Journal of the American Chemical Society 20171229 1

The synthesis of "rim-differentiated" C5-symmetric pillar[5]arenes, whose two rims are decorated with different chemical functionalities, has remained a challenging task. This is due to the inherent statistical nature of the cyclization of 1,4-disubstituted alkoxybenzenes with different substituents, which leads to four constitutional isomers with only 1/16th being rim-differentiated. Herein, we report a "preoriented" synthetic protocol based on FeCl3-catalyzed cyclization ...[more]

PMID: 29220153

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