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

Abstract

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.