An Efficient Synthesis of Organic Carbonates using Nanocrystalline Magnesium Oxide
作者:M. Lakshmi Kantam、Ujjwal Pal、B. Sreedhar、B. M. Choudary
DOI:10.1002/adsc.200600525
日期:2007.7.2
An efficient and selective synthesis of organiccarbonatesusingnanocrystallinemagnesiumoxide has been realized by the direct condensation of alcohols and diethyl carbonate. The catalyst is quantitatively recovered by simple centrifugation and can be reused for four cycles with almost consistent activity.
Immobilization of 1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene on Magnetic γ‐Fe
<sub>2</sub>
O
<sub>3</sub>
Nanoparticles: A Highly Recyclable and Efficient Nanocatalyst for the Synthesis of Organic Carbonates
作者:Liqiang Wu、Shuanbao Tian
DOI:10.1002/ejic.201301586
日期:2014.4
1,5,7-Triazabicyclo[4.4.0]dec-5-ene was immobilized on magnetic γ-Fe2O3 nanoparticles as a magneticnanocatalyst. The nanoparticle reagent was obtained with good loading levels and has been successfully used for the efficient and selective synthesis of organic carbonates by the direct condensation of alcohols and diethyl carbonate. The catalyst is quantitatively recovered by an external magnet and
Correlation between the basicity of solid bases and their catalytic activity towards the synthesis of unsymmetrical organic carbonates
作者:B VELDURTHY、J CLACENS、F FIGUERAS
DOI:10.1016/j.jcat.2004.10.024
日期:2005.1.1
The correlationbetween the basic properties of solid catalysts and the reaction rate of the selectivesynthesis of unsymmetrical organic carbonates via direct condensation of diethylcarbonate (DEC) and alcohols was investigated. A detailed kinetic study of the transesterification of 1-phenylethanol and DEC was made with catalysts with different basic strengths. The solids included fluorinated hydrotalcite
研究了固体催化剂的基本性能与通过碳酸二乙酯(DEC)和醇类直接缩合选择性合成不对称有机碳酸酯的反应速率之间的关系。使用不同的碱性强度的催化剂对1-苯基乙醇和DEC的酯交换反应进行了详细的动力学研究。固体包括氟化水滑石,MgLa混合氧化物,CsF(纯或负载在α-和γ-氧化铝上),KF(纯或负载在α-和γ-氧化铝上),锐钛矿,金红石和氧化锆。基本性质取决于CO 2的吸附通过重量分析法,质谱分析法和量热法测量。两种技术都显示出MgLa混合氧化物的更高的碱度。除了CsF / α- Al 2 O 3,尽管碱性位点的数量和强度较低,但对几种不同的底物显示出较高的活性,但反应速率与催化剂上存在的强碱性位点的数量大致成正比。。这归因于作为中间体形成的醇化物的高亲核性。将水添加到反应介质中引起两种作用:抑制反应和通过乙醇作为副反应促进底物的醚化。催化剂可以重复使用几次,而活性损失很小。
An efficient synthesis of organic carbonates: atom economic protocol with a new catalytic system
作者:Bhaskar Veldurthy、Fran�ois Figueras
DOI:10.1039/b316050e
日期:——
Selective and solvent free synthesis of unsymmetricalorganiccarbonates catalysed by a reusable MgLa mixed oxide is achieved for the first time via direct condensation of an alcohol and diethyl carbonate in economic route with excellent yields.
A green, efficient, and selectivesynthesis of unsymmetricalorganiccarbonates is realised in the liquid phase by direct condensation of an alcohol and diethyl carbonate, in an eco-compatible route, in the presence of a recyclable heterogeneous solid-base CsF/α-Al2O3 catalyst. The catalyst displayed unprecedented activity after activation at 393 K for 4 h and produced quantitative yields with a greater