2‐Pyridyl Sulfoxide: A Versatile and Removable Directing Group for the Pd
<sup>II</sup>
‐Catalyzed Direct CH Olefination of Arenes
作者:Alfonso García‐Rubia、M. Ángeles Fernández‐Ibáñez、Ramón Gómez Arrayás、Juan Carlos Carretero
DOI:10.1002/chem.201003633
日期:2011.3.21
Removable and versatile: The 2‐pyridylsulfinyl group has proved to be an efficient directinggroup in the PdII‐catalyzed aryl ortho CH olefination. This catalyst system enables the sequential double olefination to give asymmetrically di‐ortho‐functionalized arenes. The sulfinyl directinggroup can be easily cleaved, providing access to 1,3‐disubstituted arenes, or transformed into a thiol group.
Palladium-catalyzed C–H activation reactions directed by a removable 2-pyridylsulfinyl group were developed. Aromatic olefination products were formed in good yields on treatment of 2-(phenylsulfinyl)pyridines with alkenes in the presence of a Pd catalyst. The reaction tolerates a wide range of substituted alkenes, including various acrylates and styrenes. The controlled experiments indicated that