title: Photoredox activation for the direct β-arylation of ketones and aldehydes.
abstract: The direct β-activation of saturated aldehydes and ketones has long been an elusive transformation. We found that photoredox catalysis in combination with organocatalysis can lead to the transient generation of 5π-electron β-enaminyl radicals from ketones and aldehydes that rapidly couple with cyano-substituted aryl rings at the carbonyl β-position. This mode of activation is suitable for a broad range of carbonyl β-functionalization reactions and is amenable to enantioselective catalysis.
authors.affiliation: Merck Center for Catalysis, Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Pirnot
authors.forename: Danica A
authors.initials: DA
authors.lastname: Rankic
authors.forename: David B C
authors.initials: DB
authors.lastname: Martin
authors.forename: David W C
authors.initials: DW
authors.lastname: MacMillan
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D007659:Ketones / Q000737:chemistry*; D010084:Oxidation-Reduction; D055668:Photochemical Processes
chemical_list: D000447:Aldehydes; D007659:Ketones
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