Highly Active Palladium-Containing FAU Zeolite Catalyst for Suzuki–Miyaura Reaction

The supported catalysts utilized in the Suzuki–Miyaura reaction have demonstrated significant advantages over homogeneous systems. This study explores the effect of zeolite support on the catalytic performance of active Pd species, investigating a model system comprising bromobenzene and phenylboronic acid. Micro/mesoporous and Na+/H+-form FAU zeolites were synthesized by using a surfactant-templating method. Active Pd species were then anchored onto the zeolite supports via ion-exchange techniques. It was determined that the performance of Pd/zeolite catalysts is influenced by the framework structure and acidic characteristics of the zeolite supports. The micro/mesoporous hierarchical FAU zeolites demonstrated an ability to stabilize active Pd species effectively and facilitate the diffusion of larger molecules within the reaction. Moreover, the acidic sites in the H+-form FAU zeolites significantly enhanced the reaction rate due to the modulation of Pd's electronic properties by these sites. Nonetheless, Pd/zeolite (in H+-form) catalysts showed a decrease in performance, owing to the formation of extensive Pd aggregates. The Pd/zeolite catalysts also yielded comparatively high returns for various aryl iodide and bromide substrates. This study contributes additional understanding of the influence that zeolite support has on cross-coupling reactions.