demonstrated the synthesis of organic carbonates using alkyl/aryl 4,5-dichloro-6-oxopyridazine-1(6H)carboxylates and alcohol in the presence of aluminum chloride. Alkyl/aryl 4,5-dichloro-6-oxopyridazine1(6H)-carboxylates were reacted with alcohol in the presence of AlCl3 in toluene at room temperature to afford the corresponding unsymmetric and symmetric organic carbonates in good to excellent yields. These
practical lanthanide(III)-catalyzed transesterification of carboxylic esters, weakly reactive carbonates, and much less-reactive ethyl silicate with primary and secondary alcohols was developed. Heterobimetallic dinuclear lanthanidealkoxide complexes [Ln2Na8(OCH2CH2NMe2)}12(OH)2] (Ln = Nd (I), Sm (II), and Yb (III)) were used as highly active catalysts for this reaction. The mild reaction conditions enabled
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。
Organotin-oxomolybdate coordination polymer as catalyst for synthesis of unsymmetrical organic carbonates
作者:Jinliang Song、Binbin Zhang、Tainbin Wu、Guanying Yang、Buxing Han
DOI:10.1039/c0gc00765j
日期:——
Efficient and greenersynthesis of unsymmetricalorganiccarbonates is of great importance. In this work, two organotin-oxometalates, Bu2SnMoO4 and (Bu3Sn)2MoO4, were prepared and their catalytic performance for the transesterification of diethyl carbonate (DEC) with alcohols to synthesize unsymmetricalorganiccarbonates was studied. It was found that (Bu3Sn)2MoO4 was very active and selective for the transesterification