Magnetically Recyclable Pd/Fe3O4/g-C3N4 as Efficient Catalyst for the Reduction of Nitrophenol and Suzuki-Miyaura Reaction at Room Temperature

Herein, we present the design and synthesis of a novel magnetic stable and recyclable catalyst Pd/Fe3O4/g-C3N4 with approachable active palladium nanoparticles (Pd NPs) based on the platelet-like graphitic carbon nitrides (g-C3N4). The Pd NPs, g-C3N4 and magnetic particles (Fe3O4) are tightly connected through non-covalent interactions owing to the layered structure of g-C3N4 with abundant nitrogen atoms, facilitating the stability of Pd/Fe3O4/g-C3N4 and activating the Pd NPs at the same time. The Pd/Fe3O4/g-C3N4 catalyst with a narrow particle size distribution (2.55 nm) of Pd NPs displayed the maintenance of the planar structure of g-C3N4. The activity parameter of the catalyst turned out to be excellent (12.4 s−1·mM−1) by fitting the curves derived from the reduction of nitrophenol. Meanwhile, the Suzuki-Miyaura coupling reaction at room temperature processed smoothly with the Pd/Fe3O4/g-C3N4 catalyst. It is meaningful to stress that 2-bromobenzonitrile and p-tolylboronic acid could afford the medical intermediate sartanbiphenyl at total conversion without side reactions in 25 min. Furthermore, the nanocatalyst owes the properties of easy recycling using a powerful magnet as well as high turnover frequency (at least 5 runs) with retention of high catalytic activity.