Selective formation of {gamma}-lactams via C-H amidation enabled by tailored iridium catalysts

Intramolecular insertion of metal nitrenes into carbon-hydrogen bonds to form -lactam rings has traditionally been hindered by competing isocyanate formation. We report the application of theory and mechanism studies to optimize a class of pentamethylcyclopentadienyl iridium(III) catalysts for suppression of this competing pathway. Modulation of the stereoelectronic properties of the auxiliary bidentate ligands to be more electron-donating was suggested by density functional theory calculations