Microwave-Assisted Synthesis of Tris-Anderson Polyoxometalates for Facile CO<sub>2</sub> Cycloaddition
作者:Wei-Dong Yu、Yin Zhang、Yu-Yang Han、Bin Li、Sai Shao、Le-Ping Zhang、Hong-Ke Xie、Jun Yan
DOI:10.1021/acs.inorgchem.1c00019
日期:2021.3.15
(NH4)4[ZnMo6O18(C4H8NO3)(OH)3]·4H2O (1), (NH4)4[CuMo6O18(C4H8NO3)(OH)3]·4H2O (2), (TBA)3(NH4)[ZnMo6O17(C5H9O3)2(OH)]·10H2O (3) (TBA = n-C16H36N), and (NH4)4[CuMo6O18(C5H9O3)2]·16H2O (4), were synthesized by a microwave-assisted method. Single-crystal X-ray diffraction revealed that 1 and 2 contained a tris (trihydroxyl organic compounds) ligand grafted on one side, while two tris ligands were grafted on two sides to
四个新的tris-Anderson多金属氧酸盐(POMs)(NH 4)4 [ZnMo 6 O 18(C 4 H 8 NO 3)(OH)3 ]·4H 2 O(1),(NH 4)4 [CuMo 6 O 18(C 4 H 8 NO 3)(OH)3 ]·4H 2 O(2),(TBA)3(NH 4)[ZnMo 6 O 17(C 5 H 9 O 3)2(OH)]·10H 2 O(3)(TBA = n -C 16 H 36 N)和(NH 4)4 [CuMo 6 O 18(C 5 H 9 O 3)2 ]·16H 2 O (4)是通过微波辅助法合成的。X射线单晶衍射表明,1和2的一侧接有一个tris(三羟基有机化合物)配体,而两侧的两个tris配体接枝了,在3和3中形成χ/δ和δ/δ异构体。分别为4。首次获得χ/δ异构体3的1 H和13 C NMR光谱,其中6个亚甲基在1 H NMR光谱中显示6个峰,在13
Cooperative Multifunctional Organocatalysts for Ambient Conversion of Carbon Dioxide into Cyclic Carbonates
作者:Ning Liu、Ya-Fei Xie、Chuan Wang、Shi-Jun Li、Donghui Wei、Min Li、Bin Dai
DOI:10.1021/acscatal.8b01925
日期:2018.11.2
N-heterocyclic carbene precursor and a carboxyl group as proton transfer agent were synthesized and used as organocatalysts for the cycloaddition of epoxides with CO2. In this context, we have demonstrated the high activity of these one-component organocatalysts in the CO2 transformation to cyclic carbonates under ambient conditions (room temperature, 1 bar of CO2). The catalytic potential of these multifunctional
合成了一系列具有N杂环卡宾前体和羧基作为质子转移剂的钳型化合物,并将其用作有机催化剂,用于环氧化物与CO 2的环加成反应。在这种情况下,我们已经证明了这些单组分有机催化剂在环境条件(室温,1 bar CO 2)下从CO 2转化为环状碳酸酯的高活性。这些多功能有机催化剂在具有挑战性的内部环氧化物上的催化潜力特别值得一提,因为能够介导内部环氧化物与CO 2的环加成反应的有机催化剂在温和的条件下仍然稀缺。通过控制实验和DFT计算阐明了分子内的协同激活机制。
Pyridine-bridged bifunctional organocatalysts for the synthesis of cyclic carbonates from carbon dioxide
作者:Quan-Yao Liu、Lei Shi、Ning Liu
DOI:10.1177/1747519819858710
日期:2019.7
halides are used as efficient bifunctionalorganocatalysts for the synthesis of cyclic carbonates from CO2 and epoxides under mild reaction conditions. Control experiments suggest that the cycloaddition reaction is realized by the combination of the nucleophilic halide anions with hydroxyl and carboxyl groups as hydrogen bond donors. Moreover, the bifunctionalorganocatalysts can be easily recycled five
羟基和羧基官能化的咪唑鎓卤化物用作有效的双功能有机催化剂,用于在温和的反应条件下由 CO2 和环氧化物合成环状碳酸酯。对照实验表明,环加成反应是通过亲核卤化物阴离子与羟基和羧基作为氢键供体的结合来实现的。此外,双功能有机催化剂可以通过简单的过滤轻松回收5次;然而,观察到活性丧失。
Design of bifunctional quaternary phosphonium salt catalysts for CO<sub>2</sub> fixation reaction with epoxides under mild conditions
An efficient synthesis of cyclic carbonates from epoxides and CO2 under mild reaction conditions was achieved via the use of a newly designed bifunctional quaternaryphosphoniumiodide catalyst. The importance...
Catalytic, Kinetic, and Mechanistic Insights into the Fixation of CO
<sub>2</sub>
with Epoxides Catalyzed by Phenol‐Functionalized Phosphonium Salts
作者:Yuya Hu、Zhihong Wei、Anna Frey、Christoph Kubis、Chang‐Yue Ren、Anke Spannenberg、Haijun Jiao、Thomas Werner
DOI:10.1002/cssc.202002267
日期:2021.1.7
A series of hydroxy‐functionalized phosphonium salts were studied as bifunctional catalysts for the conversion of CO2 with epoxides under mild and solvent‐free conditions. The reaction in the presence of a phenol‐based phosphonium iodide proceeded via a first order rection kinetic with respect to the substrate. Notably, in contrast to the aliphatic analogue, the phenol‐based catalyst showed no product
研究了一系列羟基官能化鏻盐作为双功能催化剂,用于在温和无溶剂条件下将CO 2与环氧化物转化。在苯酚基碘化鏻存在下,反应通过相对于底物的一级反应动力学进行。值得注意的是,与脂肪族类似物相比,苯酚基催化剂没有表现出产物抑制。研究了反应速率的温度依赖性,并根据阿伦尼乌斯图确定了模型反应的活化能(E a =39.6 kJ mol -1)。还评估了底物范围。在优化的反应条件下,20个末端环氧化物在室温下转化为相应的环状碳酸酯,分离收率高达99%。该反应易于扩展,可在高达 50 g 底物的规模上进行。此外,该方法还应用于以环氧氯丙烷和苯基哌嗪为原料合成镇咳药氟哌嗪。此外,还进行了 DFT 计算,以合理化苯酚基碘化鏻催化剂的机理和高效率。计算证实了环氧化物通过碘化物盐的氢键活化,从而促进了开环步骤。值得注意的是,关于该步骤的有效吉布斯能垒对于溴化物是97 kJ mol -1 ,对于碘化物盐是72 kJ mol