Photoredox Driven Amide Synthesis from Tertiary Amines and Carboxylic Acids via C-N Bond Cleavage

This manuscript describes a visible-light-promoted, Ir-catalyzed, aerobic protocol for amide synthesis from tertiary amines and carboxylic acids. The reaction likely proceeds through alpha-C-H oxidation of the tertiary amine, followed by C-N bond cleavage via hydrolysis to the secondary amine intermediate. Concurrently, the additive CF3SO2Na reacts to activate the carboxylic acid via an acyl fluoride intermediate, which in turn reacts with the secondary amine to yield the product amides. The established conditions tolerate a wide variety of carboxylic acid substrates, including complex carboxylic acids. Furthermore, previously unreactive amine substrates such as N-methyl morpholine and tri-n-butyl amine are shown to react readily.