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A Highly Warped Heptagon-Containing sp² Carbon Scaffold via Vinylnaphthyl ?-Extension.

ABSTRACT: A new strategy is demonstrated for the synthesis of warped, negatively curved, all-sp² -carbon ?-scaffolds. Multifold C-C coupling reactions are used to transform a polyaromatic borinic acid into a saddle-shaped polyaromatic hydrocarbon (2) bearing two heptagonal rings. Notably, this Schwarzite substructure is synthesized in only two steps from an unfunctionalized alkene. A highly warped structure of 2 was revealed by X-ray crystallographic studies and pronounced flexibility of this ?-scaffold was ascertained by experimental and computational studies. Compound 2 exhibits excellent solubility, visible range absorption and fluorescence, and readily undergoes two reversible one-electron oxidations at mild potentials.

SUBMITTER: Farrell JM

PROVIDER: S-EPMC6900032 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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A Highly Warped Heptagon-Containing sp2 Carbon Scaffold via Vinylnaphthyl π-Extension.

Farrell Jeffrey M JM Grande Vincenzo V Schmidt David D Würthner Frank F

Angewandte Chemie (International ed. in English) 20190930 46

A new strategy is demonstrated for the synthesis of warped, negatively curved, all-sp2 -carbon π-scaffolds. Multifold C-C coupling reactions are used to transform a polyaromatic borinic acid into a saddle-shaped polyaromatic hydrocarbon (2) bearing two heptagonal rings. Notably, this Schwarzite substructure is synthesized in only two steps from an unfunctionalized alkene. A highly warped structure of 2 was revealed by X-ray crystallographic studies and pronounced flexibility of this π ...[more]

PMID: 31507020

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