Dual visible-light and NHC-catalyzed radical relay trifunctionalization of unactivated alkenes

Abstract

Radical trifunctionalization of unactivated alkenes remains rare and challenging, although they can provide a robust tool for the construction of molecules with high added value from simple materials. This work presents the relay dual N-heterocyclic carbene organocatalytic and visible-light photocatalytic multi-component trifunctionalization of alkyl alkenes via the merger of remote 1,4-cyano migration and alkylacylation. The method features a broad substrate scope and good compatibility of diverse functional groups. Density functional theory calculations were also carried out to rationalize the origin of this reaction. The cooperative N-heterocyclic carbene and photoredox catalysis enabled reductive single-electron transfer reaction of acyl azolium species and subsequent radical-radical cross-coupling, allowing for the facile construction of three new C−C bonds in one-pot reactions with high regioselectivity.

Keywords

N-heterocyclic carbene / photocatalysis / trifunctionalization / radical / remote CN migration

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