Nanoarchitectonics of Palladium Nanoparticles Supported on Carbon‐Based Heterogeneous Catalysts for C─H Activation Reaction

Abstract Organic reactions involving the direct functionalization of non‐activated C─H bonds represent a valuable class of transformations, enhancing atom, and step economy while streamlining chemical synthesis. However, the high stability of C─H bonds often necessitate harsh reaction conditions, significantly limiting their application in synthesizing complex organic molecules. In order to break the inert C─H bond and convert it into the useful C─C, C─O, C─X, and C─N conversion under benign conditions, several active and selective catalytic systems have been designed. Metal (Pd)‐supported carbon‐based heterogeneous catalysts offer a promising approach in this context. Different type of support such as graphene oxide, reduced graphene oxide and carbon nanotubes are used as a support material. Pd(II) species activates the C─H bond, and involved in an oxidation and reduction cycle involving insertion to the substrate and regeneration of catalytic active site. The activation of C─H bonds in hydrocarbons involves the insertion of a metal into the C─H bond resulting in the formation of an organometallic complex which then reacts with another substrate (reaction partner) to yield the final product. Sometime the efficiency of Pd metal can be increased by using another metal which helps to reduce the HOMO–LUMO gap and stabilize the catalyst. Therefore, this minireview discuss the most recent advancement of Pd supported on carbon based heterogeneous catalyst for C─H bond activation.