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Direct ?-functionalization of cyclic ketones with aryl ketones via the merger of photoredox and organocatalysis.

ABSTRACT: The direct ?-coupling of cyclic ketones with aryl ketones has been achieved via the synergistic combination of photoredox catalysis and organocatalysis. Diaryl oxymethyl or aryl-alkyl oxymethyl radicals, transiently generated via single-electron reduction of ketone precursors, readily merge with ?-enaminyl radical species, generated by photon-induced enamine oxidation, to produce ?-hydroxyketone adducts. Experimental evidence indicates that two discrete reaction pathways can be operable in this process depending upon the nature of the ketyl radical precursor and the photocatalyst.

SUBMITTER: Petronijevic FR

PROVIDER: S-EPMC3934322 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Direct β-functionalization of cyclic ketones with aryl ketones via the merger of photoredox and organocatalysis.

Petronijević Filip R FR Nappi Manuel M MacMillan David W C DW

Journal of the American Chemical Society 20131122 49

The direct β-coupling of cyclic ketones with aryl ketones has been achieved via the synergistic combination of photoredox catalysis and organocatalysis. Diaryl oxymethyl or aryl-alkyl oxymethyl radicals, transiently generated via single-electron reduction of ketone precursors, readily merge with β-enaminyl radical species, generated by photon-induced enamine oxidation, to produce γ-hydroxyketone adducts. Experimental evidence indicates that two discrete reaction pathways can be operable in this ...[more]

PMID: 24237366

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