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Enantioselective Synthesis of 1,12-Disubstituted [4]Helicenes.

ABSTRACT: A highly enantioselective synthesis of 1,12-disubstituted [4]carbohelicenes is reported. The key step for the developed synthetic route is a Au-catalyzed intramolecular alkyne hydroarylation, which is achieved with good to excellent regio- and enantioselectivity by employing TADDOL-derived (TADDOL=?,?,?,?-tetraaryl-1,3-dioxolane-4,5-dimethanol) ?-cationic phosphonites as ancillary ligands. Moreover, an appropriate design of the substrate makes the assembly of [4]helicenes of different substitution patterns possible, thus demonstrating the synthetic utility of the method. The absolute stereochemistry of the newly prepared structures was determined by X-ray crystallography and characterization of their photophysical properties is also reported.

SUBMITTER: Hartung T

PROVIDER: S-EPMC7154633 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Enantioselective Synthesis of 1,12-Disubstituted [4]Helicenes.

Hartung Thierry T Machleid Rafael R Simon Martin M Golz Christopher C Alcarazo Manuel M

Angewandte Chemie (International ed. in English) 20200220 14

A highly enantioselective synthesis of 1,12-disubstituted [4]carbohelicenes is reported. The key step for the developed synthetic route is a Au-catalyzed intramolecular alkyne hydroarylation, which is achieved with good to excellent regio- and enantioselectivity by employing TADDOL-derived (TADDOL=α,α,α,α-tetraaryl-1,3-dioxolane-4,5-dimethanol) α-cationic phosphonites as ancillary ligands. Moreover, an appropriate design of the substrate makes the assembly of [4]helicenes of different substituti ...[more]

PMID: 31961992

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