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Accessing Medium-Sized Rings via Vinyl Carbocation Intermediates.

ABSTRACT: Medium-sized rings (8-11-membered cycles) are often more challenging to synthesize than smaller rings (5-7-membered cycles) due to ring strain. Herein, we report a catalytic method for forming 8- and 9-membered rings that proceeds via the intramolecular Friedel-Crafts reactions of vinyl carbocation intermediates. These reactive species are generated catalytically through the ionization of vinyl toluenesulfonates by a Lewis acidic lithium cation-weakly coordinating anion salt.

SUBMITTER: Zhao Z

PROVIDER: S-EPMC10863392 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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Accessing Medium-Sized Rings via Vinyl Carbocation Intermediates.

Zhao Zhenqi Z Zhao Zhenqi Z Popov Stasik S Lee Woojin W Burch Jessica E JE Delgadillo David A DA Kim Lee Joon LJ Shahgholi Mona M Lebrón-Acosta Naiara N Houk K N KN Nelson Hosea M HM

Organic letters 20240131 5

Medium-sized rings (8-11-membered cycles) are often more challenging to synthesize than smaller rings (5-7-membered cycles) due to ring strain. Herein, we report a catalytic method for forming 8- and 9-membered rings that proceeds via the intramolecular Friedel-Crafts reactions of vinyl carbocation intermediates. These reactive species are generated catalytically through the ionization of vinyl toluenesulfonates by a Lewis acidic lithium cation-weakly coordinating anion salt. ...[more]

PMID: 38295154

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