Highly Regioselective Remote Lithiation of Functionalized 1,3-bis-Silylated Arenes.

Substituted arenes flanked by two bulky triethylsilyl groups were regiospecifically lithiated at the 5-position with nBuLi⋅PMDTA at 25 °C. The resulting aryllithiums reacted with a broad range of electrophiles such as ketones, isocyanates, Weinreb amides, allyl bromides, and CO2 at 25 °C. These bis-silylated arenes were then converted in simple reaction sequences into silyl-free tetrasubstituted arenes. This remote lithiation was extended to 2,6-bis(triethylsilyl)pyridine as well as 3,3'-bis(triethylsilyl)biphenyl.