Electrophotocatalytic Reductive 1,2‐Diarylation of Alkenes with Aryl Halides and Cyanoaromatics.

Comprehensive Summary: The radical‐mediated reductive functionalization of aryl halides has been extensively studied. However, the related radical‐mediated intermolecular reductive 1,2‐diarylation of alkenes, using aryl halides as aryl radical sources, remains unexplored. Herein, a new electrophotocatalytic intermolecular reductive 1,2‐diarylation of alkenes is reported using aryl halides and cyanoaromatics to produce polyarylated alkanes. Using synergistic cathodic reduction and visible‐light photoredox catalysis, various electron‐rich and electron‐deficient aryl halides are combined with various alkenes and cyanoaromatics to characterize the broad substrate scope, excellent functional group compatibility, and excellent selectivity of this reaction. Mechanistic investigations reveal that this reaction may proceed via a radical process initiated by the reductive generation of aryl radicals from aryl halides and terminated by radical‐radical coupling with cyanoaromatic radical anions. [ABSTRACT FROM AUTHOR]