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Oxidative Heck vinylation for the synthesis of complex dienes and polyenes.

ABSTRACT: We introduce an oxidative Heck reaction for selective complex diene and polyene formation. The reaction proceeds via oxidative Pd(II)/sulfoxide catalysis that retards palladium-hydride isomerizations which previously limited the Heck manifold's capacity for furnishing stereodefined conjugated dienes. Limiting quantities of nonactivated terminal olefins (1 equiv) and slight excesses of vinyl boronic esters (1.5 equiv) that feature diverse functionality can be used to furnish complex dienes and polyenes in good yields and excellent selectivities (generally E:Z = >20:1; internal:terminal = >20:1). Because this reaction only requires prior activation of a single vinylic carbon, improvements in efficiency are observed for synthetic sequences relative to ones featuring reactions that require activation of both coupling partners.

SUBMITTER: Delcamp JH

PROVIDER: S-EPMC4084759 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Oxidative Heck vinylation for the synthesis of complex dienes and polyenes.

Delcamp Jared H JH Gormisky Paul E PE White M Christina MC

Journal of the American Chemical Society 20130530 23

We introduce an oxidative Heck reaction for selective complex diene and polyene formation. The reaction proceeds via oxidative Pd(II)/sulfoxide catalysis that retards palladium-hydride isomerizations which previously limited the Heck manifold's capacity for furnishing stereodefined conjugated dienes. Limiting quantities of nonactivated terminal olefins (1 equiv) and slight excesses of vinyl boronic esters (1.5 equiv) that feature diverse functionality can be used to furnish complex dienes and po ...[more]

PMID: 23701421

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