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Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling.

ABSTRACT: Photochemical enantioselective nickel-catalyzed cross-coupling reactions are difficult to implement. We report a visible-light-mediated strategy that successfully couples symmetrical anhydrides and 4-alkyl dihydropyridines (DHPs) to afford enantioenriched ?-substituted ketones under mild conditions. The chemistry does not require exogenous photocatalysts. It is triggered by the direct excitation of DHPs, which act as a radical source and as a reductant, facilitating the turnover of the chiral catalytic nickel complex.

SUBMITTER: Gandolfo E

PROVIDER: S-EPMC6900114 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling.

Gandolfo Eugenio E Tang Xinjun X Raha Roy Sudipta S Melchiorre Paolo P

Angewandte Chemie (International ed. in English) 20191007 47

Photochemical enantioselective nickel-catalyzed cross-coupling reactions are difficult to implement. We report a visible-light-mediated strategy that successfully couples symmetrical anhydrides and 4-alkyl dihydropyridines (DHPs) to afford enantioenriched α-substituted ketones under mild conditions. The chemistry does not require exogenous photocatalysts. It is triggered by the direct excitation of DHPs, which act as a radical source and as a reductant, facilitating the turnover of the chiral ca ...[more]

PMID: 31532568

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