Enantioselective C(sp3)–H Amidation of Thioamides Catalyzed by a CobaltIII/Chiral Carboxylic Acid Hybrid System

We go together: Thioamide‐directed C(sp³)−H amidation using dioxazolones was achieved with good enantioselectivity through the hybridization of a readily available cobalt catalyst and a chiral amino acid derivative. This method provides a straightforward route to chiral β‐amino carbonyl building blocks. Irreversible and enantioselective cleavage of the C(sp³)−H bond was achieved through chiral‐carboxylate‐assisted concerted metalation–deprotonation.

Abstract

Recent advances in Cp^xM^III catalysis (M=Co, Rh, Ir) have enabled a variety of enantioselective C(sp²)−H functionalization reactions, but enantioselective C(sp³)−H functionalization is still largely unexplored. We describe an asymmetric C(sp³)−H amidation of thioamides using an achiral Co^III/chiral carboxylic acid hybrid catalytic system, which provides easy and straightforward access to chiral β‐amino thiocarbonyl and β‐amino carbonyl building blocks with a quaternary carbon stereocenter.

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