Recent Methodologies That Exploit Oxidative Addition of C-N Bonds to Transition Metals

The activation of sigma-bonds by transition metals underpins a wide range of methods for the synthesis of complex molecules. Within this context, C-N bond activation has emerged recently as a powerful strategy for the preparation or utilization of nitrogen-containing compounds, due to the prevalence of C-N bonds in organic compounds. A key challenge in this area is that most C-N bonds are relatively inert, and this makes their activation a difficult task. Since the turn of the millennium the number of published articles regarding C-N bond activation has grown exponentially, providing important improvements in methodologies for such transformations. Indeed, several distinct strategies have been developed to achieve C-N bond activation. The most common have exploited either strain release or quaternization of the nitrogen center, while other state-of-the-art strategies, such as oxidative addition of neutral C-N bonds and the use of directing groups, have also appeared. Despite considerable progress, deeper insight into the mechanisms of activation and improvements in atom economy are still required for the field to advance. In this Perspective we give an overview of key advances in catalytic methodologies where C-N bond activation is achieved by oxidative addition to transition metals.