一种制备石墨烯-Fe 3 O 4复合材料的一步法及其优异的催化活性,可用于醛,炔烃和胺的三组分偶联†
摘要:
具有磁性纳米粒子的还原氧化石墨烯或氧化石墨烯(GO)的结构因其在催化,光电材料,生物医学领域等领域的广阔前景而受到越来越多的关注。具有良好分散的装饰颗粒的还原性氧化石墨烯(RGO)或石墨烯磁性纳米颗粒纳米复合材料的合成仍然是一个挑战。在此,我们首先报告一种简单的方法,该方法基于氧化石墨烯表面上的Fe(CO)5分解制备具有均匀Fe 3 O 4 NP的石墨烯– Fe 3 O 4。这项工作的主要新颖之处在于,Fe(CO)5的分解产物与GO反应导致石墨烯-Fe的形成。3 O 4。所得样品可以容易地受到外部磁场的操纵,并且在A 3偶联反应中表现出优异的催化活性。在温和条件下以中等至高收率获得了各种炔丙基胺。石墨烯-Fe 3 O 4的分离和再利用非常简单,有效和经济。
Cu-grafted mesoporous organic polymer: a new recyclable nanocatalyst for multi-component, N-arylation and S-arylation reactions
作者:Noor Salam、Sudipta K. Kundu、Anupam Singha Roy、Paramita Mondal、Susmita Roy、Asim Bhaumik、Sk. Manirul Islam
DOI:10.1039/c3cy00600j
日期:——
A new mesoporous Cu-MPTA-1 nanocatalyst has been synthesized via a simple and facile in situ radical polymerization of triallylamine in the presence of an organic–organic self-assembly of anionic surfactant SDS, followed by grafting of Cu(II) at room temperature under an inert atmosphere. This nanomaterial has been characterized by elemental analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV–vis diffuse reflectance spectroscopy (DRS), thermogravimetric analysis (TGA), N2 adsorption–desorption studies, X-ray photoelectron spectroscopy (XPS) and EPR spectroscopy. Cu-MPTA-1 acts as an efficient heterogeneous nanocatalyst exhibiting a high catalytic activity for N-arylation and S-arylation reactions using water as a green solvent and also exhibits an excellent catalytic activity for the one-pot synthesis of propargylamines via a three component coupling of an alkyne, an amine and an aldehyde at room temperature. Moreover, the catalyst is easily recoverable and can be reused six times without an appreciable loss of catalytic activity in the three component coupling reaction. The highly dispersed Cu(II) sites in the Cu-grafted mesoporous polymer could be responsible for the observed high activities of the Cu-MPTA-1 catalyst in the coupling reactions. No evidence of leached Cu from the catalyst during the course of the reaction has been observed, suggesting true heterogeneity in the catalytic process.
Synthesis of silver–graphene nanocomposite and its catalytic application for the one-pot three-component coupling reaction and one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles in water
作者:Noor Salam、Arjyabaran Sinha、Anupam Singha Roy、Paramita Mondal、Nikhil R. Jana、Sk Manirul Islam
DOI:10.1039/c3ra47466f
日期:——
reaction between in situ generated azides (derived from anilines or amines) and terminal acetylenes. This solid silver–graphene catalyst has been characterized by TEM, Raman, XRD and UV-Visible absorption spectra. The developed catalyst is air-stable, inexpensive, easy to prepare and can be facilely recovered and reused five times without significant decrease in activity and selectivity.
A one-step method to produce graphene–Fe<sub>3</sub>O<sub>4</sub>composites and their excellent catalytic activities for three-component coupling of aldehyde, alkyne and amine
作者:Xing Huo、Jian Liu、Baodui Wang、Haoli Zhang、Zhengyin Yang、Xuegong She、Pinxian Xi
DOI:10.1039/c2ta00485b
日期:——
the decomposition products of Fe(CO)5 reacted with GO leading to the formation of graphene–Fe3O4. The resulting sample can be easily manipulated by an external magnetic field and exhibits excellent catalytic activity in the A3-coupling reaction. A diverse range of propargylamines were obtained in a moderate to high yield under mild conditions. The separation and reuse of graphene–Fe3O4 were very simple
具有磁性纳米粒子的还原氧化石墨烯或氧化石墨烯(GO)的结构因其在催化,光电材料,生物医学领域等领域的广阔前景而受到越来越多的关注。具有良好分散的装饰颗粒的还原性氧化石墨烯(RGO)或石墨烯磁性纳米颗粒纳米复合材料的合成仍然是一个挑战。在此,我们首先报告一种简单的方法,该方法基于氧化石墨烯表面上的Fe(CO)5分解制备具有均匀Fe 3 O 4 NP的石墨烯– Fe 3 O 4。这项工作的主要新颖之处在于,Fe(CO)5的分解产物与GO反应导致石墨烯-Fe的形成。3 O 4。所得样品可以容易地受到外部磁场的操纵,并且在A 3偶联反应中表现出优异的催化活性。在温和条件下以中等至高收率获得了各种炔丙基胺。石墨烯-Fe 3 O 4的分离和再利用非常简单,有效和经济。
Excellent catalytic activity of magnetically recoverable Fe<sub>3</sub>O<sub>4</sub>–graphene oxide nanocomposites prepared by a simple method
作者:Prasenjit Mandal、Asoke P. Chattopadhyay
DOI:10.1039/c5dt01260k
日期:——
An easy-to-prepare Fe3O4–graphene oxide nanocomposite which works well as a reusable catalyst for A3-coupling reactions.