γ-Amino C(sp³)–H Functionalization of Aliphatic Amines through a Light-Driven Triple Catalysis

Abstract

We report intra- and intermolecular γ-amino C(sp3)–H functionalization of aliphatic amines using a vinylsulfone-based HAT (hydrogen atom transfer) auxiliary and a triple catalysis, which is composed of photoredox, cobalt, and Brønsted acid catalysts under visible light irradiation. The process accomplishes four elementary steps: (i) electrophilic carbon-centered radical formation on the HAT auxiliary via MHAT (metal hydride hydrogen atom transfer) reaction, (ii) generation of a γ-amino carbon-centered radical through 1,6-HAT reaction, (iii) single-electron oxidation to carbocation equivalents, and (iv) nucleophilic substitution with internal or external nucleophiles. As a result, this γ-amino C(sp3)–H functionalization afforded γ-amino-functionalized products, such as azetidines, 1,3-diamine, and 1,3-aminoalcohol derivatives.