Accessing alpha-Amino Ketyl Radicals from beta-Amino Alcohols via Chemoselective Hydrogen Atom Transfer Catalysis

The selective activation of a given C-H bond in complex molecules possessing bonds of similar polarity and strength remains one of the foremost challenges in hydrogen atom transfer (HAT) catalysis. Herein, we present the combination of photoredox and HAT catalysis with an oxophiic boron-based catalyst to achieve the chemoselective abstraction of alpha-hydroxy C-H bonds in beta-amino alcohols. This enables us to access alpha-amino ketyl radicals, which are exploited for the direct synthesis of gamma-oxo-delta-amino esters-a prominent scaffold in biologically active molecules.

Automated summary

This study presents a combination of photoredox and hydrogen atom transfer (HAT) catalysis using an oxophilic boron-based catalyst to selectively abstract alpha-hydroxy C-H bonds in beta-amino alcohols. The obtained alpha-amino ketyl radicals are then utilized for the direct synthesis of gamma-oxo-delta-amino esters, which are important scaffolds in biologically active molecules.