Copper-Catalyzed Radical Acyl-Cyanation of Alkenes with Mechanistic Studies on the tert-Butoxy Radical

A copper-catalyzed radical acyl-cyanation of alkenes with aldehydes, employing TBHP as an initiator, has been developed and is reported in this study. Mechanistic studies support the radical pathway of the reaction, which starts from a tert-butoxy radical. Theoretical studies with DFT calculations and our experimental results suggest that metal species is the dominant factor for the β-Me scission of Ot-Bu radical rather than temperature, and the β-Me scission of a free Ot-Bu radical is concentration-dependent kinetically unfavorable in the presence of aldehydes in this reaction.