Metal-catalyzed C---H activation/functionalization: The fundamentals
Résumé
An isolated Csingle bondH bond in a molecule has a very low reactivity owing to the large kinetic barrier associated to the Csingle bondH bond cleavage and the apolar nature of this bond. For this reason, the selective reactivity of such a non-functional group is under active study since several decades and is still regarded as the Holy Grail in chemistry. Metal-catalyzed Csingle bondH activation/functionalization chemistry allows the step-economical and original construction of Csingle bondC as well as Csingle bondO and Csingle bondN bonds starting from hydrocarbons (or hydrocarbon fragments) without the need of prior non catalytic oxidation steps. Furthermore, it can be of utmost importance in the domain of multistep syntheses, and also in transformations of societal significance such as the conversion of methane into methanol. This tutorial review addresses to students and researchers who would like to become acquainted with this fascinating topic. After a brief historical introduction, the main mechanistic fundaments of metal-catalyzed Csingle bondH activation are exposed. Then, a selection of seminal advances and conceptual breakthroughs are presented.