Visible-Light-Driven Reductive 1,2-Diarylation of Alkenes via O-Tethered Iodoarenes and Cyanopyridines.

The diarylation of alkenes represents one of the most efficient strategies for constructing complex architectures. Reported herein is a distinct photoredox cascade approach for alkene diarylation, achieved via the radical cyclization of O-tethered iodoarenes followed by coupling with 4-cyanopyridines. Notably, this protocol relies on the dual role of the cyanoheteroarenes. Beyond serving as the requisite heteroaryl source, they act as essential electron-transfer mediators to facilitate the cleavage of aryl C(sp2)-I bonds under visible-light irradiation. Furthermore, this photochemical strategy features readily accessible substrates and broad functional group compatibility, providing a practical platform for the efficient synthesis of diverse dihydrobenzofuran derivatives.