Ortho-Palladation of Primary Amines: The Myth Dispelled

Cyclopalladation reactions are well known processes widely studied, because they represent a facile method for the activation of a C–H bond in aromatic rings and have potential applications in organic synthesis. A large variety of N-containing ligands has been cyclometalated, including tertiary amines. Nevertheless, only very recently, a general method to ortho-palladate primary aryl-alkylamines has been reported. This review deals mainly with the synthesis, but also with the structure and reactivity, of ortho-metalated complexes containing this kind of ligand. In addition, it will try to summarize the reasons that make so different the behavior of tertiary and primary amines towards direct palladation.