title: Proton-abstraction mechanism in the palladium-catalyzed intramolecular arylation: substituent effects.
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.
authors.affiliation: Institute of Chemical Research of Catalonia, Av. Països Catalans 16, 43007 Tarragona, Spain.
authors.forename: Domingo
authors.initials: D
authors.lastname: García-Cuadrado
authors.forename: Paula
authors.initials: P
authors.lastname: de Mendoza
authors.forename: Ataualpa A C
authors.initials: AA
authors.lastname: Braga
authors.forename: Feliu
authors.initials: F
authors.lastname: Maseras
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Echavarren