Abstract In this study, a novel catalyst system with high activity and easy recoverability was successfully prepared through the deposition of Pd nanoparticles (NPs) onto designed sustainable hybrid beads containing magnetic cobalt ferrite and chitosan (Pd/CoFe2O4/chitosan). The catalytic potential of Pd/CoFe2O4/chitosan hybrid nanocatalyst was then assessed in i) preparation of benzonitriles via aryl halides cyanation and ii) reduction of 2-nitroaniline (2-NA). Various aryl iodides and bromides were successfully cyanated by Pd/CoFe2O4/chitosan hybrid nanocatalyst with excellent reaction yields within 3 h. In addition to the production of benzonitriles, the hybrid nanocatalyst showed excellent activity by reducing 2-NA in 65 s. It was proved that the Pd/CoFe2O4/chitosan hybrid nanocatalyst outperformed many catalysts used in the cyanation of aryl halides and catalytic reduction of 2-NA previously reported in the literature. Moreover, it was found that the designed Pd/CoFe2O4/chitosan hybrid nanocatalyst was easily and effectively separated from the reaction mixture using an external magnet and reused several times in catalytic reactions without considerable loss of catalytic activity.

中文翻译：

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Pd/CoFe2O4/壳聚糖：一种高效且易于回收的杂化纳米催化剂，用于合成苯甲腈和还原 2-硝基苯胺

摘要 在本研究中，通过将 Pd 纳米粒子 (NPs) 沉积在含有磁性钴铁氧体和壳聚糖 (Pd/CoFe2O4/壳聚糖) 的可持续混合珠上，成功制备了一种具有高活性和易回收性的新型催化剂体系。然后在 i) 通过芳基卤氰化制备苯甲腈和 ii) 2-硝基苯胺 (2-NA) 还原中评估 Pd/CoFe2O4/壳聚糖杂化纳米催化剂的催化潜力。各种芳基碘化物和溴化物被 Pd/CoFe2O4/壳聚糖杂化纳米催化剂成功氰化，反应产率在 3 小时内表现出色。除了生产苯甲腈外，混合纳米催化剂还通过在 65 秒内还原 2-NA 显示出优异的活性。事实证明，Pd/CoFe2O4/壳聚糖杂化纳米催化剂的性能优于之前文献中报道的用于芳基卤化物氰化和2-NA催化还原的许多催化剂。此外，还发现设计的 Pd/CoFe2O4/壳聚糖杂化纳米催化剂使用外部磁铁可以轻松有效地从反应混合物中分离出来，并在催化反应中重复使用多次，而催化活性没有显着损失。