Ghamari Kargar Pouya, Bagherzade Ghodsieh
Department of Chemistry, Faculty of Sciences, University of Birjand Birjand 97175-615 Iran
RSC Adv. 2021 Jul 1;11(38):23192-23206. doi: 10.1039/d1ra00208b.
The new recyclable cobalt three-core magnetic catalyst obtained by anchoring a Schiff base ligand sector and cellulose nanofiber slings on MNP (FeO) was prepared and named as MNP@CNF@ATSM-Co(ii). Separately, MNPs and CNF have adsorbent properties of great interest. In this way, this catalyst was designed to synthesize piperidine derivatives under solvent-free conditions and alcohol oxidation reactions in EtOH as the solvent. It should be noted that this catalyst is environmentally safe and does not need an external base. This MNPs@CNF@ATSM-Co(ii) separable catalyst has been evaluated using various characterization techniques such as FT-IR, XRD, FE-SEM, EDX, EDS, ICP, TGA, DLS, HRTEM, and VSM. The catalyst was compatible with a variety of benzyl alcohols, benzaldehydes, and amines derivatives, and gave complimentary coupling products with sufficient interest for all of them. The synergistic performance of Co (trinuclear) in the catalyst was demonstrated and its different homologs such as MNPs, MNPs@CNF, MNPs@CNF@ATS-Co(ii), and MNPs@CNF@ATSM-Co(ii) were separately synthesized and applied to a model reaction, and then their catalytic activity was investigated. Also, the performance of these components for the oxidation reaction of alcohols was evaluated. The advantages of the current protocol include the use of a sustainable and safe low temperature, eco-friendly solvent no additive, and long-term stability and magnetic recyclability of the catalyst for at least five successive runs, thus following green chemistry principles. This protocol is a benign and environment-friendly method for oxidation and heterocycle synthesis. This powerful super-magnetic catalyst can use its three arms to advance the reactions, displaying its power for multi-component reactions and oxidation.
通过将席夫碱配体部分和纤维素纳米纤维吊索锚定在MNP(FeO)上获得了新型可回收钴三核磁性催化剂，并将其命名为MNP@CNF@ATSM-Co(ii)。另外，MNPs和CNF具有非常令人感兴趣的吸附性能。通过这种方式，设计该催化剂在无溶剂条件下合成哌啶衍生物，并在以乙醇为溶剂的醇氧化反应中使用。需要注意的是，该催化剂对环境安全，且不需要外部碱。已使用FT-IR、XRD、FE-SEM、EDX、EDS、ICP、TGA、DLS、HRTEM和VSM等各种表征技术对这种MNPs@CNF@ATSM-Co(ii)可分离催化剂进行了评估。该催化剂与多种苄醇、苯甲醛和胺衍生物兼容，并为所有这些物质提供了具有足够吸引力的互补偶联产物。证明了催化剂中Co(三核)的协同性能，并分别合成了其不同的同系物，如MNPs、MNPs@CNF、MNPs@CNF@ATS-Co(ii)和MNPs@CNF@ATSM-Co(ii)，并将其应用于模型反应，然后研究了它们的催化活性。此外，还评估了这些组分在醇氧化反应中的性能。当前方案的优点包括使用可持续且安全的低温、生态友好的无添加剂溶剂，以及催化剂至少连续五次运行的长期稳定性和磁性可回收性，从而遵循绿色化学原则。该方案是一种用于氧化和杂环合成的良性且环境友好的方法。这种强大的超磁性催化剂可以用其三臂推进反应，展示其在多组分反应和氧化中的能力。
