Ligand‐Free Pd‐Catalyzed Synthesis of PAHs via Vinyl C−H Activation/Decarboxylative Cyclization Sequence

Herein, we describe a strategy for the synthesis of polycyclic aromatic hydrocarbons (PAHs) from readily available 2‐iodostyrenes and o‐halobenzoic acids through a ligand‐free palladium‐catalyzed cascade vinyl C−H activation/decarboxylative cyclization. A vinyl‐coordinated five‐membered palladacycle was proposed as the key intermediate for this sequential process. Furthermore, Heptagon‐embedded aromatic compounds can be smoothly synthesized by employing 8‐bromo‐1‐naphthoic acid as decarboxylative insertion unit.