C−H Arylation on Nickel Nanoparticles Monitored by In Situ Surface‐Enhanced Raman Spectroscopy

Abstract Bifunctional Au@Ni core–satellite nanostructures synthesized by a one‐step assembly method were employed for in situ surface‐enhanced Raman spectroscopic (SERS) monitoring of Ni‐catalyzed C−C bond‐forming reactions. Surprisingly, the reaction that was thought to be an Ullmann‐type self‐coupling reaction, was found to be a cross‐coupling reaction proceeding by photoinduced aromatic C−H bond arylation. In situ SERS monitoring enabled the discovery, and a series of biphenyl compounds were synthesized photocatalytically, and at room temperature, using cheap Ni nanoparticle catalysts.