Photoredox‐Catalyzed Generation of Tertiary Anions from Primary Amines via a Radical Polar Crossover

Abstract A method for the generation of tertiary carbanions via a deaminative radical‐polar crossover is reported using redox active imines from α‐tertiary primary amines. A variety of benzylic amines and amino esters can be used in this approach, with the latter engaging in a novel “aza‐Reformatsky” reaction. Electronic trends correlate the stability of the resulting carbanion with reaction efficiency. The anions can be trapped with different electrophiles including aldehydes, ketones, imines, Michael acceptors, and H 2 O/D 2 O. Selective anion formation can be achieved in the presence of another equivalent or more acidic C−H bond in both an inter‐ and intramolecular fashion. Mechanistic studies suggest the intermediacy of a discrete carbanion intermediate.