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Intermolecular Heck Coupling with Hindered Alkenes Directed by Potassium Carboxylates.

ABSTRACT: Pd0 -catalyzed Mizoroki-Heck reactions traditionally exhibit poor reactivity with polysubstituted, unbiased alkenes. Intermolecular reactions with simple, all-carbon tetrasubstituted alkenes are unprecedented. Herein we report that pendant carboxylic acids, combined with bulky monophospine ligands on palladium, can direct the arylation of tri- and tetrasubstituted olefins. Quaternary carbons are established at high Fsp3 attached-ring junctures and the carboxylate directing group can be removed after coupling. Carboxylate directivity prevents over-arylation of the new, less substituted alkene, which can be diversified in subsequent reactions.

SUBMITTER: Huffman TR

PROVIDER: S-EPMC6370521 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Intermolecular Heck Coupling with Hindered Alkenes Directed by Potassium Carboxylates.

Huffman Tucker R TR Wu Yebin Y Emmerich Alexis A Shenvi Ryan A RA

Angewandte Chemie (International ed. in English) 20190125 8

Pd0 -catalyzed Mizoroki-Heck reactions traditionally exhibit poor reactivity with polysubstituted, unbiased alkenes. Intermolecular reactions with simple, all-carbon tetrasubstituted alkenes are unprecedented. Herein we report that pendant carboxylic acids, combined with bulky monophospine ligands on palladium, can direct the arylation of tri- and tetrasubstituted olefins. Quaternary carbons are established at high Fsp3 attached-ring junctures and the carboxylate directing ...[more]

PMID: 30602064

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