García-Cuadrado Domingo, de Mendoza Paula, Braga Ataualpa A C, Maseras Feliu, Echavarren Antonio M
Institute of Chemical Research of Catalonia, Av. Països Catalans 16, 43007 Tarragona, Spain.
J Am Chem Soc. 2007 May 30;129(21):6880-6. doi: 10.1021/ja071034a. Epub 2007 Apr 27.
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.
在取代溴苄基二芳基甲烷的分子内钯催化芳基化反应中观察到的区域选择性以及理论结果表明，钯催化的芳基化反应是通过碳酸酯或相关碱性配体进行质子提取的机制进行的。芳环上的吸电子取代基促进了该反应，这与亲电芳香取代机制不一致。更重要的导向作用是由反应位点邻位的吸电子取代基施加的。
