Kour Gurpreet, Gupta Monika
Department of Chemistry, University of Jammu, Jammu-180006, India.
Dalton Trans. 2017 May 30;46(21):7039-7050. doi: 10.1039/c7dt00822h.
Silver nanoparticles have been prepared from a chemical reduction approach and supported on modified TEOS (tetraethylorthosilicate) xerogels to be studied as a nanocatalyst in the conversions of benzopyranopyrimidines (with primary as well as secondary amines along with the mechanism by trapping the imine intermediate) and also in the synthesis of gem-bisamides. Different conditions for the performance of the nanocatalyst have been screened and tolerance with respect to variable functionalities has been observed, resulting in excellent yields; and confirmation of products synthesized has been done using studies like H NMR, C NMR and mass analysis. Also, SEM-EDX and TEM of the nanocatalyst have been performed to know the internal and external morphology, size and elemental composition. UV and XRD analysis to confirm the silver nanoparticles' and xerogel's presence, TGA to study the thermal stability and FTIR to study the modification pattern of the nanocatalyst have been undertaken and presented in this work.
通过化学还原法制备了银纳米颗粒,并将其负载在改性的原硅酸四乙酯(TEOS)干凝胶上,用于研究其作为纳米催化剂在苯并吡喃嘧啶转化反应(与伯胺和仲胺反应,并通过捕获亚胺中间体研究反应机理)以及偕二酰胺合成中的应用。筛选了纳米催化剂性能的不同条件,并观察了其对可变官能团的耐受性,从而获得了优异的产率;通过¹H NMR、¹³C NMR和质谱分析等研究对合成的产物进行了确认。此外,还对纳米催化剂进行了扫描电子显微镜-能谱分析(SEM-EDX)和透射电子显微镜(TEM)分析,以了解其内部和外部形态、尺寸和元素组成。本工作还进行并展示了紫外和X射线衍射分析以确认银纳米颗粒和干凝胶的存在,热重分析(TGA)以研究热稳定性,以及傅里叶变换红外光谱(FTIR)以研究纳米催化剂的改性模式。