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Ketone-Olefin Coupling of Aliphatic and Aromatic Carbonyls Catalyzed by Excited-State Acridine Radicals.

ABSTRACT: Ketone-olefin coupling reactions are common methods for the formation of carbon-carbon bonds. This reaction class typically requires stoichiometric or super stoichiometric quantities of metal reductants, and catalytic variations are limited in application. Photoredox catalysis has offered an alternative method toward ketone-olefin coupling reactions, although most methods are limited in scope to easily reducible aromatic carbonyl compounds. Herein, we describe a mild, metal-free ketone-olefin coupling reaction using an excited-state acridine radical super reductant as a photoredox catalyst. We demonstrate both intramolecular and intermolecular ketone-olefin couplings of aliphatic and aromatic ketones and aldehydes. Mechanistic evidence is also presented supporting an "olefin first" ketone-olefin coupling mechanism.

SUBMITTER: Venditto NJ

PROVIDER: S-EPMC10031806 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Ketone-Olefin Coupling of Aliphatic and Aromatic Carbonyls Catalyzed by Excited-State Acridine Radicals.

Venditto Nicholas J NJ Liang Yiyang S YS El Mokadem Roukaya K RK Nicewicz David A DA

Journal of the American Chemical Society 20220623 26

Ketone-olefin coupling reactions are common methods for the formation of carbon-carbon bonds. This reaction class typically requires stoichiometric or super stoichiometric quantities of metal reductants, and catalytic variations are limited in application. Photoredox catalysis has offered an alternative method toward ketone-olefin coupling reactions, although most methods are limited in scope to easily reducible aromatic carbonyl compounds. Herein, we describe a mild, metal-free ketone-olefin co ...[more]

PMID: 35737516

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