Molecular Engineered Palladium Single Atom Catalyst with M-C1N3 Subunit for Suzuki Coupling

Abstract

Single atom catalysis has emerged as powerful techniques for catalysis due to its outstanding performance and atom economy. Controlling the hybridization of the atom with its environment is crucial in dictating the selectivity and/or yield of the reaction. However, the single atom environment is usually ill-defined and hard to predict because the pyrolysis process used in preparing the SAC damages the original status of the precursors in the catalyst preparation. A molecular engineering approach to synthesize single atom catalysts (SACs) on a heterogeneous template provides a strategy to make SAC with highly uniform coordinating environment. Herein, we report the preparation of molecular engineered Pd single atom catalyst with the pre-defined M-N3C1 coordination (Pd-N3C1-SAC) using the structure-rigid Pd-N3C1 porphyrin as the precursor, which shows a more efficient Suzuki coupling compared with SAC catalyst with Pd-N4 coordination. The origin of the high activity of Pd-N3C1-SAC is revealed through density functional theory calculations, where a lower reaction barrier for the rate-determining oxidative addition is identified.