Under the usual conditions, the Pd-catalyzed arylation does not involve an electrophilic aromatic substitution reaction. On the basis of DFT calculations, we propose a mechanism for the Pd-catalyzed arylation that involves a proton abstraction by a carbonate or related ligand and that provides a satisfactory explanation for the experimental data.
Proton Abstraction Mechanism for the Palladium-Catalyzed Intramolecular Arylation
J. Am. Chem. Soc. 2006, 128, 1066-1067.