Photoredox-Catalyzed Intermolecular Radical Arylthiocyanation/Arylselenocyanation of Alkenes: Access to Aryl-Substituted Alkylthiocyanates/Alkylselenocyanates

An
efficient and highly selective approach for intermolecular arylthiocyanation/arylselenocyanation
of alkenes has been reported under mild conditions. Using diazonium
salts as the arylating agent and ammonium thiocyanate as the thiocyanate
source, chemoselective difunctionalization of alkenes has been done
under irradiation of visible light. Both styrenes and acrylates work
well to deliver various aryl-substituted alkylthiocyanates in good
to excellent yields. In addition, hitherto unknown β-aryl alkylselenocyanates
were also synthesized using the developed protocol with potassium
selenocyanate.