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](https://www.iciq.org/wp-content/uploads/2014/03/Proton-abstraction-mechanism_eng_noticies_articles_2006_76.gif)