The benzylic functionalization of alkylpyridines is an important pathway for pyridine derivate synthesis. The reaction partners, however, were mostly limited to highly reactive polar electrophiles. Herein, we report a potassium amide-catalyzed selective benzylic C-H bond addition of alkylpyridines to styrenes. This easily available Brønsted base catalyst, potassium bis(trimethylsilyl)amide (KHMDS), showed excellent activity and chemoselectivity. A series of alkylpyridine derivatives including benzylic quaternary carbon substituted ones were obtained in good to high yield. Preliminary mechanism studies revealed that the deprotonation equilibrium was probably responsible for the excellent selectivity.
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