Proton-Abstraction Mechanism in the Palladium-Catalyzed Intramolecular Arylation: Substituent Effects
作者:Domingo García-Cuadrado、Paula de Mendoza、Ataualpa A. C. Braga、Feliu Maseras、Antonio M. Echavarren
DOI:10.1021/ja071034a
日期:2007.5.1
The regioselectivity observed in the intramolecularpalladium-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
Bidentate phosphines as ligands in the palladium-catalyzed intramolecular arylation: the intermolecular base-assisted proton abstraction mechanism
作者:Sergio Pascual、Paula de Mendoza、Ataualpa A.C. Braga、Feliu Maseras、Antonio M. Echavarren
DOI:10.1016/j.tet.2008.01.056
日期:2008.6
The palladium-catalyzed arylation of aryl bromides can be carried out in the presence of bidentatephosphines, such as dppm, dppe, dppf, and Xantphos under mild conditions. The experimental results and the DFT calculations fully support for this reaction a mechanism proceeding by an intermolecular proton abstraction.