Department of Chemistry, Faculty of Science, Imam Khomeini International University, Qazvin, Iran.
Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Sci Rep. 2021 Oct 8;11(1):20021. doi: 10.1038/s41598-021-99121-2.
Recently magnetic nanocatalyst has attracted considerable attention because of its unique properties, including high performance, easy separation from the reaction mixture, and recyclability. In this study, a novel magnetic bionanocomposite was synthesized with chitosan and tannic acid as a natural material. The synthesized bionanocatalyst was characterized by essential analysis. FeO@chitosan-tannic acid as a heterogeneous nanocatalyst was successfully applied to synthesize pyranopyrazole and its derivatives by a one-pot four-component reaction of malononitrile, ethyl acetoacetate, hydrazine hydrate, and various aromatic aldehyde. At the end of the reaction, the nanocatalyst was separated from the reaction mixture and was reused several times with no significant decrease in its catalytic performance. Simple purification of products, the ability for recovering and reusing the nanocatalyst, eco-friendliness, high yields of pure products, mild reaction conditions, short reaction time, non-toxicity, economically affordable are some of the advantages of using the fabricated nanocatalyst in the synthesis of pyranopyrazole.
近年来，由于具有独特的性能，包括高性能、易于从反应混合物中分离和可重复使用，磁性纳米催化剂引起了相当大的关注。在这项研究中，我们用壳聚糖和鞣酸作为天然材料合成了一种新型的磁性生物纳米复合材料。通过必要的分析对合成的生物纳米催化剂进行了表征。FeO@壳聚糖-鞣酸作为一种多相纳米催化剂，成功地应用于通过丙二腈、乙酰乙酸乙酯、水合肼和各种芳香醛的一锅四组分反应合成吡喃并吡唑及其衍生物。反应结束后，纳米催化剂从反应混合物中分离出来，并重复使用了几次，其催化性能没有明显下降。产物的简单纯化、纳米催化剂的回收和再利用能力、环境友好性、高纯度产物的产率、温和的反应条件、短的反应时间、无毒、经济实惠是使用所制备的纳米催化剂合成吡喃并吡唑的一些优点。
