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Selective Radical-Radical Cross-Couplings: Design of a Formal ?-Mannich Reaction.

ABSTRACT: A direct ?-coupling of cyclic ketones with imines has been accomplished via the synergistic combination of photoredox catalysis and organocatalysis. Transient ?-enaminyl radicals derived from ketones via enamine and oxidative photoredox catalysis readily combine with persistent ?-amino radicals in a highly selective hetero radical-radical coupling. This novel pathway to ?-aminoketones is predicated upon the use of DABCO as both a base and an electron transfer agent. This protocol also formally allows for the direct synthesis of ?-Mannich products via a chemoselective three-component coupling of aryl aldehydes, amines, and ketones.

SUBMITTER: Jeffrey JL

PROVIDER: S-EPMC4629778 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Selective Radical-Radical Cross-Couplings: Design of a Formal β-Mannich Reaction.

Jeffrey Jenna L JL Petronijević Filip R FR MacMillan David W C DW

Journal of the American Chemical Society 20150629 26

A direct β-coupling of cyclic ketones with imines has been accomplished via the synergistic combination of photoredox catalysis and organocatalysis. Transient β-enaminyl radicals derived from ketones via enamine and oxidative photoredox catalysis readily combine with persistent α-amino radicals in a highly selective hetero radical-radical coupling. This novel pathway to γ-aminoketones is predicated upon the use of DABCO as both a base and an electron transfer agent. This protocol also formally a ...[more]

PMID: 26075347

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