Eisavi Ronak, Karimi Asmar
Department of Chemistry, Payame Noor University PO BOX 19395-3697 Tehran Iran
RSC Adv. 2019 Sep 20;9(51):29873-29887. doi: 10.1039/c9ra06038c. eCollection 2019 Sep 18.
A magnetically separable CoFeO/Cu(OH) nanocomposite was prepared and characterized by various techniques such as FESEM, EDS, TEM, XRD, VSM and FT-IR. This novel composite was used as a heterogeneous catalyst for the regioselective synthesis of β-hydroxy-1,4-disubstituted-1,2,3-triazoles from sodium azide, terminal alkynes and structurally different epoxides in water at 60 °C. The formation of the product proceeds in one pot through a mechanism that involves an generated organic azide intermediate, followed by rapid ring closure with the alkyne component. The simple procedure, short reaction times, perfect regioselectivity, high product yields, and use of a benign solvent and nontoxic catalyst are among the considerable advantages of this protocol. Furthermore, the catalyst was easily separated using an external magnet and reused several times without any significant loss of catalytic activity or magnetic properties.
制备了一种磁分离的CoFeO/Cu(OH)纳米复合材料,并通过场发射扫描电子显微镜(FESEM)、能谱仪(EDS)、透射电子显微镜(TEM)、X射线衍射仪(XRD)、振动样品磁强计(VSM)和傅里叶变换红外光谱仪(FT-IR)等多种技术对其进行了表征。这种新型复合材料被用作多相催化剂,用于在60℃的水中由叠氮化钠、末端炔烃和结构不同的环氧化物区域选择性合成β-羟基-1,4-二取代-1,2,3-三唑。产物的形成通过一锅法进行,其机理涉及生成的有机叠氮化物中间体,随后与炔烃组分快速闭环。该方法具有操作简单、反应时间短、区域选择性完美、产物收率高以及使用良性溶剂和无毒催化剂等显著优点。此外,该催化剂可通过外部磁铁轻松分离,并可重复使用多次,而催化活性或磁性没有任何明显损失。