Visible‐Light Induced C(sp<sup>2</sup>)−H Amidation with an Aryl–Alkyl σ‐Bond Relocation via Redox‐Neutral Radical–Polar Crossover
Hyeyun Keum, Hoimin Jung, Jiwoo Jeong, Dongwook Kim, Sukbok Chang
Abstract
)-H amidation of N-acyloxyamides under photoredox conditions to produce δ-benzolactams with an aryl-alkyl σ-bond relocation. Computational studies on the designed reductive single electron transfer strategy led us to identify N-[3,5-bis(trifluoromethyl)benzoyl] group as the most effective amidyl radical precursor. Upon the formation of an azaspirocyclic radical intermediate by the selective ipso-addition with outcompeting an ortho-attack, radical-polar crossover was then rationalized to lead to the rearomative ring-expansion with preferential C-C bond migration.
Topics & Concepts
ChemistryIntramolecular forceAlkylArylAryl radicalTrifluoromethylPhotochemistryPolarMedicinal chemistryRedoxElectron transferRing (chemistry)StereochemistryOrganic chemistryAstronomyPhysicsRadical Photochemical ReactionsCatalytic C–H Functionalization MethodsSulfur-Based Synthesis Techniques