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Radical-Based C-C Bond-Forming Processes Enabled by the Photoexcitation of 4-Alkyl-1,4-dihydropyridines.

ABSTRACT: We report herein that 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) can directly reach an electronically excited state upon light absorption and trigger the generation of C(sp3 )-centered radicals without the need for an external photocatalyst. Selective excitation with a violet-light-emitting diode turns alkyl-DHPs into strong reducing agents that can activate reagents through single-electron transfer manifolds while undergoing homolytic cleavage to generate radicals. We used this photochemical dual-reactivity profile to trigger radical-based carbon-carbon bond-forming processes, including nickel-catalyzed cross-coupling reactions.

SUBMITTER: Buzzetti L

PROVIDER: S-EPMC5698711 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Radical-Based C-C Bond-Forming Processes Enabled by the Photoexcitation of 4-Alkyl-1,4-dihydropyridines.

Buzzetti Luca L Prieto Alexis A Roy Sudipta Raha SR Melchiorre Paolo P

Angewandte Chemie (International ed. in English) 20171024 47

We report herein that 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) can directly reach an electronically excited state upon light absorption and trigger the generation of C(sp<sup>3</sup> )-centered radicals without the need for an external photocatalyst. Selective excitation with a violet-light-emitting diode turns alkyl-DHPs into strong reducing agents that can activate reagents through single-electron transfer manifolds while undergoing homolytic cleavage to generate radicals. We used this photoc ...[more]

PMID: 28984403

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