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Triple Helicene Cage: Three-Dimensional ?-Conjugated Chiral Cage with Six [5]Helicene Units.

ABSTRACT: A three-dimensional ?-conjugated chiral cage with six [5]helicene units (a triple helicene cage) was synthesized for the first time. Taking advantage of the Yamamoto coupling reaction, the triflate-substituted triple [5]helicene, a strained and preorganized precursor, was dimerized to afford the target compound. Single-crystal X-ray diffraction analysis revealed the unique structural features of the triple helicene cage: a cage-shaped rigid structure with outer helical grooves and an inner chiral cavity. All-P and all-M enantiomers were separated successfully by HPLC over a chiral column and their chiroptical properties were characterized by circular dichroism spectra.

SUBMITTER: Matsushima T

PROVIDER: S-EPMC5891663 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Triple Helicene Cage: Three-Dimensional π-Conjugated Chiral Cage with Six [5]Helicene Units.

Matsushima Tomoya T Kikkawa Shoko S Azumaya Isao I Watanabe Soichiro S

ChemistryOpen 20180216 4

A three-dimensional π-conjugated chiral cage with six [5]helicene units (a triple helicene cage) was synthesized for the first time. Taking advantage of the Yamamoto coupling reaction, the triflate-substituted triple [5]helicene, a strained and preorganized precursor, was dimerized to afford the target compound. Single-crystal X-ray diffraction analysis revealed the unique structural features of the triple helicene cage: a cage-shaped rigid structure with outer helical grooves and an inner chira ...[more]

PMID: 29657913

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