Palladium-Catalyzed ortho-C(sp2)–H Silylation of Aromatic Ketones Using an Aminooxyamide Auxiliary

A palladium-catalyzed direct and selective ortho-C­(sp2)–H silylation of aromatic ketones has been achieved using an aminooxyamide auxiliary. The reaction tolerates various orth-, meta-, and para- substituents on the aromatic ring and can be applied to thiophenyl and vinyl ketones. The ortho-C­(sp2)–H bond was monosilylated selectively in comparison with other aromatic C–H bonds, benzyl or allylic C­(sp3)–H bonds, and acidic α-C­(sp3)–H bonds. The aminooxyamide auxiliary can be easily installed and readily removed after the silylation reaction. The resulting ortho-silyl aromatic ketone derivatives are potentially useful building blocks for organic synthesis.