Pd NPs@Fe3O4/chitosan/pumice hybrid beads: A highly active, magnetically retrievable, and reusable nanocatalyst for cyanation of aryl halides.

In this study, Fe3O4/chitosan/pumice hybrid beads were developed as a new stabilizer agent, and palladium nanoparticles (Pd NPs) were successfully decorated on the designed stabilizer without adding any toxic reducing resource. Then, the potential use of Pd NPs@Fe3O4/chitosan/pumice hybrid beads as a heterogeneous catalyst against different aryl halide cyanations was investigated with K4[Fe(CN)6]. In these reactions, Pd NPs@ Fe3O4/chitosan /pumice hybrid beads showed high catalytic activity by converting aryl halides to the desired benzonitriles with high product yields (80 %-98 %). Due to the magnetically separable nature of Pd NPs@Fe3O4/chitosan/pumice hybrid beads, they were reused several times, and 86 % yield was obtained even after six successive runs. This paper reveals that Pd NPs@Fe3O4/chitosan/pumice hybrid beads have a high potential to synthesis a broad range of nitriles due to their excellent catalytic and retrievable capability.