Cu(II) immobilized on guanidinated epibromohydrin‐functionalized γ‐Fe<sub>2</sub>O<sub>3</sub>@TiO<sub>2</sub>(γ‐Fe<sub>2</sub>O<sub>3</sub>@TiO<sub>2</sub>‐EG‐Cu(II)): A highly efficient magnetically separable heterogeneous nanocatalyst for one‐pot synthesis of highly substituted imidazoles
作者:Mahdi Nejatianfar、Batool Akhlaghinia、Roya Jahanshahi
DOI:10.1002/aoc.4095
日期:2018.2
A simple, efficient and eco‐friendly procedure has been developed using Cu(II) immobilized on guanidinated epibromohydrin‐functionalized γ‐Fe2O3@TiO2 (γ‐Fe2O3@TiO2‐EG‐Cu(II)) for the synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent‐free conditions
一种简单,高效和环境友好的程序已被使用的Cu(II)固定于显影胍基化表溴醇-官能化了γ-Fe 2 ö 3 @TiO 2(γ-的Fe 2 ö 3 @TiO 2 -EG-的Cu(II))在无溶剂条件下,通过各种醛与苯甲酰和乙酸铵或乙酸铵和胺的缩合反应,合成2,4,5-三取代和1,2,4,5-四取代的咪唑。这种催化剂的高分辨率透射电子显微镜分析明确肯定一个形成了γ-Fe 2 ö 3芯和的TiO 2外壳,平均大小分别约为10–20 nm和5–10 nm。这些数据与X射线晶体学测量(13和7 nm)非常吻合。此外,磁化测量结果表明,这两种了γ-Fe 2 ö 3 @TiO 2和γ-的Fe 2 ö 3 @TiO 2 -EG-的Cu(II)具有超顺磁性与22.12鸸鹋克23.79饱和磁化强度和行为-1分别。了γ-Fe 2 ö 3 @TiO 2‐EG‐Cu(II)被发现是一种绿色高效的纳米催化剂,可以容易地