Green bio‐based synthesis of Fe
<sub>2</sub>
O
<sub>3</sub>
@SiO
<sub>2</sub>
‐IL/Ag hollow spheres and their catalytic utility for ultrasonic‐assisted synthesis of propargylamines and benzo[
<i>b</i>
]furans
作者:Samahe Sadjadi、Majid M. Heravi、Masoumeh Malmir
DOI:10.1002/aoc.4029
日期:2018.2
A novel magnetic hybrid system containing nano‐magnetic Fe2O3 hollow spheres, silica shell, [pmim]Cl ionic liquid and silver nanoparticles was synthesized and characterized. The silver nanoparticles were prepared via biosynthesis using Achillea millefolium flower as reducing and stabilizing agent. The hybrid system was successfully used as an efficient and reusable catalyst for promoting green ultrasonic‐assisted
合成并表征了一种新型的磁混合系统,该系统包含纳米磁性的Fe 2 O 3空心球,二氧化硅壳,[pmim] Cl离子液体和银纳米颗粒。通过使用A草花作为还原剂和稳定剂,通过生物合成来制备银纳米颗粒。该杂化系统已成功用作促进绿色超声辅助A 3和KA 2偶联反应以及苯并[ b]的有效且可重复使用的催化剂。呋喃合成。发现用非磁性部分装饰磁芯会降低最大饱和磁化强度。但是,催化剂仍然是超顺磁性的,可以使用外部磁体将其简单地从反应混合物中分离出来。通过研究催化剂的可重复使用性和稳定性以及银的浸出,也证实了催化剂的非均质性质。使用水性介质,高收率,较短的反应时间,宽的底物耐受性和所需的催化剂量低是该方案的优点。
Facile and efficient synthesis of polyfunctionalized benzofurans: three-component coupling reactions from an alkynylsilane, an o-hydroxybenzaldehyde derivative, and a secondary amine by a Cu(I)–Cu(II) cooperative catalytic system
作者:Norio Sakai、Naoki Uchida、Takeo Konakahara
DOI:10.1016/j.tetlet.2008.03.111
日期:2008.5
DMAP effectively catalyzed a three-component coupling reaction involving an alkynylsilane, an o-hydroxybenzaldehyde derivative, and a secondary amine. The reaction proceeded via intramolecular 5-exo-dig cyclization, resulting in direct synthesis of the corresponding benzofuranderivatives in moderate to excellent yields.