Substituted Hantzsch Esters as Versatile Radical Reservoirs in Photoredox Reactions

Substituted Hantzsch esters can act as radical reservoirs in photoredox reactions, steadily releasing a carbon radical and a hydrogen atom radical in the absence of an additional electron acceptor. We propose that radical release by substituted Hantzsch esters occurs via a mechanism involving an internal redox cycle. Cinnamidecinnamides, styrenes, alpha,beta-unsaturated acids, and diarylethenes could be alkylated smoothly with these reagents.