Green synthesis of palladium nanocatalyst derived from the beta-cyclodextrin used as effective heterogeneous catalyst for cyanation of aryl halides

In this study, preparation of highly stable palladium nanoparticles (Pd NPs) on Schiff base modified beta-cyclodextrin (beta-CD-Sch) in the absence of reducing agents has been successfully carried out. Pd NPs@beta-CD-Sch has then been applied as nanocatalyst in the synthesis of benzonitriles via cyanation reaction using K4Fe(CN)(6), which is a low cost, commercially available and non-toxic cyanide source. A series of benzonitriles containing different substrates were successfully fabricated with 77-98% yields using Pd NPs@beta-CD-Sch. Moreover, Pd NPs@beta-CD-Sch catalyst was quantitatively recovered and reutilized several times, showing good reaction yields. This work revealed that i) prepared beta-CD-Sch is an effective stabilizer for the fabrication of Pd NPs and ii) Pd NPs@beta-CD-Sch catalyst play an important role in the fabrication of benzonitriles.