C–H Amination Chemistry Mediated by Trinuclear Cu(I) Sites Supported by a Ligand Scaffold Featuring an Arene Platform and Tetramethylguanidinyl Residues†

A crown-shaped Cu 3 Cl 3 fragment captured by a ligand that features tetramethylguanidinyl residues and an apically oriented arene platform gives rise to a potent benzylic and tert -C–H bond amination catalyst via a computed dicopper nitrene oxidant.