B(C6F5)3-Catalyzed C-H Alkylation of N-Alkylamines Using Silicon Enolates without External Oxidant.

An efficient method for the coupling of N-alkylamines with silicon enolates to generate β-amino carbonyl compounds is disclosed. These reactions proceed by activation of α-amino C-H bonds by B(C6F5)3, which likely generates a "frustrated" acid/base complex in the presence of large N-alkylamines. The transformation requires no external oxidant and releases hydrosilane as a byproduct. The utility of this method is demonstrated in the late-stage functionalization of bioactive molecules such as citalopram, atomoxetine, and fluoxetine.