载金属-有机骨架封装杂多酸的壳聚糖珠作为一种有效的串联缩合反应催化剂。

Chitosan bead containing metal-organic framework encapsulated heteropolyacid as an efficient catalyst for cascade condensation reaction.

机构信息

Gas Conversion Department, Faculty of Petrochemicals, Iran Polymer and Petrochemical Institute, P.O. Box 14975-112, Tehran, Iran.

Department of Chemistry, School of Physics and Chemistry, Alzahra University, P.O. Box 1993891176, Vanak, Tehran, Iran.

出版信息

Sci Rep. 2023 Feb 16;13(1):2797. doi: 10.1038/s41598-023-29548-2.

Abstract

Using cyclodextrin and chitosan that are bio-based compounds, a novel bi-functional catalytic composite is designed, in which metal-organic framework encapsulated phosphomolybdic acid was incorporated in a dual chitosan-cyclodextrin nanosponge bead. The composite was characterized via XRD, TGA, ICP, BET, NH-TPD, FTIR, FE-SEM/EDS, elemental mapping analysis and its catalytic activity was examined in alcohol oxidation and cascade alcohol oxidation-Knoevenagel condensation reaction. It was found that the designed catalyst that possess both acidic feature and redox potential could promote both reactions in aqueous media at 55 °C and various substrates with different electronic features could tolerate the aforementioned reactions to furnish the products in 75-95% yield. Furthermore, the catalyst could be readily recovered and recycled for five runs with slight loss of the catalytic activity. Notably, in this composite the synergism between the components led to high catalytic activity, which was superior to each component. In fact, the amino groups on the chitosan served as catalysts, while cyclodextrin nanosponge mainly acted as a phase transfer agent. Moreover, measurement of phosphomolybdic acid leaching showed that its incorporation in metal-organic framework and bead structure could suppress its leaching, which is considered a drawback for this compound. Other merits of this bi-functional catalyst were its simplicity, use of bio-based compounds and true catalysis, which was proved via hot filtration.

摘要

利用生物基化合物环糊精和壳聚糖,设计了一种新型双功能催化复合材料,其中金属有机骨架封装的磷钼酸被包裹在双壳聚糖-环糊精纳米海绵珠中。通过 XRD、TGA、ICP、BET、NH-TPD、FTIR、FE-SEM/EDS、元素映射分析对复合材料进行了表征,并考察了其在醇氧化和级联醇氧化-Knoevenagel 缩合反应中的催化活性。结果表明,所设计的催化剂具有酸性和氧化还原电位,可在 55°C 的水相中促进这两种反应,并且具有不同电子特征的各种底物可以耐受上述反应,以 75-95%的产率得到产物。此外,该催化剂可以很容易地回收并循环使用五次,催化活性略有损失。值得注意的是,在这种复合材料中,各组分之间的协同作用导致了高催化活性,优于各组分单独的催化活性。事实上,壳聚糖上的氨基起到了催化剂的作用,而环糊精纳米海绵主要起到相转移剂的作用。此外,对磷钼酸浸出的测量表明,其在金属有机骨架和珠体结构中的结合可以抑制其浸出,这被认为是该化合物的一个缺点。这种双功能催化剂的其他优点是其简单性、使用生物基化合物和真正的催化作用,这通过热过滤得到了证明。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/ab94/9935902/e65e7ec0d62e/41598_2023_29548_Sch1_HTML.jpg

相似文献

本文引用的文献

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索