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Updated: Jul 15, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Proton-abstraction mechanism in the palladium-catalyzed intramolecular arylation: substituent effects
Domingo García-Cuadrado1, Paula de Mendoza, Ataualpa A C Braga
1Institute of Chemical Research of Catalonia, Av. Països Catalans 16, 43007 Tarragona, Spain.
Abstract:
The regioselectivity observed in the intramolecular palladium-catalyzed arylation of substituted bromobenzyldiarylmethanes as well as theoretical results demonstrate that the Pd-catalyzed arylation proceeds by a mechanism involving a proton abstraction by the carbonate, or a related basic ligand. The reaction is facilitated by electron-withdrawing substituents on the aromatic ring, which is inconsistent with an electrophilic aromatic-substitution mechanism. The more important directing effect is exerted by electron-withdrawing substituents ortho to the reacting site.
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