Palladium-Catalyzed Regioselective Arylation of Arene C-H Bond Assisted by the Removable 2-Pyridylsulfinyl Group
作者:Yuhong Zhang、Xunbin Zhang、Ming Yu、Jinzhong Yao
DOI:10.1055/s-0031-1290320
日期:2012.2
A palladium-catalyzed arylation of arene C-H bond assisted by a removable 2-pyridylsulfinyl group is described. The reaction employs aryltrifluoroborates as the arylation reagent, leading to the corresponding products in moderate to good yield with broad substrate scope. The directinggroup can be removed or converted to other useful functionalities, which showcases the potential synthetic application
Modifiable Sulfur Tethers as Directing Groups for Aromatic CH Acetoxylation Reactions
作者:Heinrich Richter、Stephan Beckendorf、Olga García Mancheño
DOI:10.1002/adsc.201000941
日期:2011.2.11
A designed new class of modifiable sulfur tethers for aromatic CH bond functionalizations is presented. As a model, the palladium-catalyzed directed acetoxylation reaction was studied. The more challenging sulfoxide tethers were the most effective in this transformation, showing a broad functionality tolerance, high S oxido-redox stability and no catalyst poisoning. Preliminary mechanistic studies
Palladium-Catalyzed Coupling of Arene C–H Bonds with Methyl- and Arylboron Reagents Assisted by the Removable 2-Pyridylsulfinyl Group
作者:José A. Romero-Revilla、Alfonso Garcı́a-Rubia、Ramón Goméz Arrayás、M. Ángeles Fernández-Ibáñez、Juan C. Carretero
DOI:10.1021/jo2018137
日期:2011.11.18
The Pd-II-catalyzed direct coupling of arene C-H bonds with organoboron reagents assisted by the 2-pyridylsulfinyl group is reported. Methylboronic acid and arylboronic acid neopentyl esters proved to be efficient coupling partners, furnishing methylated arenes and biaryl products in moderate to good yields. The 2-pyridylsulfinyl group can be easily removed to provide the free biaryls. The essential role of the 2-pyridyl unit in stabilizing the cyclopalladation complex was demonstrated by X-ray diffraction analysis of the palladacycle intermediate.