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Functionalization at Will of Rim-Differentiated Pillar[5]arenes.

ABSTRACT: The development of an efficient synthetic route toward rim-differentiated C₅-symmetric pillar[5]arenes (P[5]s), whose two rims are decorated with different chemical functionalities, opens up successive transformations of this macrocyclic scaffold. This paper describes a gram-scale synthesis of a C₅-symmetric penta-hydroxy P[5] precursor, and a range of highly efficient reactions that allow functionalizing either rim at will via, e.g., sulfur(VI) fluoride exchange (SuFEx) reactions, esterifications, or Suzuki-Miyaura coupling. Afterward, BBr₃ demethylation activates another rim for similar functionalizations.

SUBMITTER: Demay-Drouhard P

PROVIDER: S-EPMC6558637 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Functionalization at Will of Rim-Differentiated Pillar[5]arenes.

Demay-Drouhard Paul P Du Ke K Samanta Kushal K Wan Xintong X Yang Weiwei W Srinivasan Rajavel R Sue Andrew C-H AC Zuilhof Han H

Organic letters 20190419 11

The development of an efficient synthetic route toward rim-differentiated C5-symmetric pillar[5]arenes (P[5]s), whose two rims are decorated with different chemical functionalities, opens up successive transformations of this macrocyclic scaffold. This paper describes a gram-scale synthesis of a C5-symmetric penta-hydroxy P[5] precursor, and a range of highly efficient reactions that allow functionalizing either rim at will via, e.g., sulfur(VI) fluoride exchange (SuFEx) re ...[more]

PMID: 31002251

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