New amine modified nanozeolites were prepared and characterized using FT-IR, TGA, DTG, SEM, and TEM. Then the synthesized nanozeolites were employed as novel, recyclable and safe catalysts for the one-pot, three-component condensation of 4-hydroxycoumarin with aldehydes and malononitrile to produce new and known pyrano[2,3-c]chromenes as potent biologically active compounds. This novel method has many advantages, such as high product yield and a simple work-up procedure.
Design, preparation, and characterization of Fe<sub>3</sub>O<sub>4</sub>nanoparticles encapsulating<i>β</i>‐cyclodextrin‐bearing guanidine as a highly efficient and reusable heterogeneous base catalyst for synthesis of 3,4‐dihydropyrano[3,2‐<i>c</i>]chromenes
作者:Soraya Rahmatinejad、Hossein Naeimi
DOI:10.1002/aoc.5862
日期:2020.10
materials showing biological activities. Here, a simple and convenient procedure for the synthesis of 3,4‐dihydropyrano[3,2‐c]chromene derivatives is described. For this purpose, Fe3O4 nanoparticles supported on β‐cyclodextrin‐guanidine were successfully prepared and used as catalyst. The structure of this catalyst was assigned by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron
ne烯亚结构是存在于多种具有生物活性的药物,天然产物和材料中的重要结构基序。在这里,描述了一种简单而方便的合成3,4-二氢吡喃并[3,2- c ]色烯衍生物的方法。为此,将Fe 3 O 4纳米颗粒负载在β上环糊精胍已成功制备并用作催化剂。该催化剂的结构通过傅里叶变换红外光谱,X射线衍射,扫描电子显微镜,热重分析和振动样品磁力计技术进行分配。制备的纳米复合材料可用作高活性,多相和可重复使用的纳米催化剂,用于4-羟基香豆素,芳族醛和氰基乙酸乙酯的一锅,三组分反应。该方法具有条件温和,收率高,产品易于后处理和纯化简单,催化剂负载少,成本效率高和催化剂可重复使用等优点。
Copper‐amine complex immobilized on nano NaY zeolite as a recyclable nanocatalyst for the environmentally friendly synthesis of 2‐amino‐4
<i>H</i>
‐chromenes
catalytic activity of the synthesized nano-sample was evaluated in a three-component synthesis of 2-amino-4H-chromene derivatives, which resulted in high reaction yields and short reaction times under green conditions. The catalyst is separated by filtration and can be reused for at least seven consecutive runs without significant loss of catalytic activity. The nature of the supported [2-(3-[(2-ami
catalyst, simple product separation from the reaction mixture and generality of the method, easy handling, low catalyst cost, and mild reaction conditions make this approach an eco-friendly procedure for synthesizing the chromenes. The obtained results demonstrated that the presented catalytic procedure could be effective in the synthesis of other useful products under green reaction conditions. Graphical
本研究通过用3-氯丙基三甲氧基硅烷(CPTMS)对纳米NaY沸石(YZ)进行后改性,然后合成纳米NaY沸石负载二甲双胍(YZ/PS/Met)作为一种环保且可重复使用的纳米催化剂。与二甲双胍(Met)反应。采用傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、动态光散射(DLS)、热重分析等多种技术对二甲双胍功能化纳米NaY沸石(YZ/PS/Met)进行了表征(TGA)、场发射扫描电子显微镜 (FESEM)、能量色散 X 射线光谱 (EDS)、Brauer-emmett-teller (BET)、t 图和元素分析。然后,选择2-氨基-4H-色烯的合成来研究(YZ/PS/Met)的催化活性,该方法在室温下提供了良好的产率(81-98%)、反应时间短、和绿色溶剂(EtOH)。该催化剂可以轻松地从反应介质中去除,并可连续重复使用七次,而不会显着降低催化剂性能。 NaY 表面附着的二甲双胍 (Met)