Photoredox Catalyzed Site-Selective Generation of Carbanions from C(sp3)-H bonds in Amines

Abstract

The selective activation of sp3 carbon-hydrogen bonds in presence of multiple C¬-H bonds is challenging and remains of supreme importance in chemical research. Herein, we describe the activation of a C(sp3) H bond in α position to an amine via a carbanion intermediate. In the presence of several α amine sites, only one specific position is selectively activated. Applying this protocol, the proposed carbanion intermediate was effectively trapped with different electrophiles such as deuterium (D+), tritium (T+), or carbonyl compounds compiling over 50 examples. Further, this methodology was used to install deuterium or tritium in different drug derivatives (> 10 drugs) at a selected position in a late-stage functionalization. In addition, the protocol is suitable for a gram-scale synthesis and a detailed mechanistic investigation has been carried out to support our hypothesis.