New lanthanide(iii) coordination polymers: synthesis, structural features, and catalytic activity in CO2 fixation.
New lanthanide(iii) coordination polymers: synthesis, structural features, and catalytic activity in CO2 fixation.
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DOI：
10.1039/c7dt03574h
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发表时间：
2017-12
影响因子：
4
通讯作者：
Cong Xu;Yan Liu;Li Wang;Jing-xin Ma;Lizi Yang;Fuyan Pan;A. Kirillov;Weisheng Liu
中科院分区：
文献类型：
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作者：
Cong Xu;Yan Liu;Li Wang;Jing-xin Ma;Lizi Yang;Fuyan Pan;A. Kirillov;Weisheng Liu
[Ln(μ-L)(μ-L)(H2O)]nXn (Ln/X = Er/Cl (1), Er/Br (2), Tm/Cl (3), Tm/Br （4), Yb/Cl (5), Yb/Br (6))）L = 1,3-双（4-羧基苯基）咪唑羧酸盐（1+）)是溶剂热合成的，并进行了充分的表征。单晶x射线衍射分析表明，所有产物均具有由阳离子一维双链包裹卤化物阴离子组成的同构结构。从拓扑学的角度来看，这种一维链可以被分类为一个双节的3,5连通网络，其唯一拓扑由点符号（3·42）（32·42·53·62·7）定义。所有产物1-6均具有良好的热稳定性，可作为高活性的非均相催化剂用于卤化环氧丙烷与CO2的偶联反应，生成相应的环状碳酸盐。研究了反应条件、底物和催化剂范围以及催化转化的机理特征。在温和的反应条件下获得了高产品收率（高达98%），高吨（高达3920）或tof（高达326 h-1）。此外，催化剂6可以至少回收八次而不损失催化活性。
A new series of lanthanide coordination polymers formulated as [Ln(μ-L)(μ3-L)(H2O)]nXn (Ln/X = Er/Cl (1), Er/Br (2), Tm/Cl (3), Tm/Br (4), Yb/Cl (5), and Yb/Br (6); L = 1,3-bis(4-carboxyphenyl) imidazolium carboxylate(1+)) were solvothermally generated and fully characterized. Single-crystal X-ray diffraction analysis shows that all products possess isomorphous structures that are composed of cationic 1D double chains with encapsulated halide anions. From a topological perspective, such 1D chains can be classified as a binodal 3,5-connected net with a unique topology defined by the point symbol of (3·42)(32·42·53·62·7). All products 1-6 feature a remarkable thermal stability and were applied as highly active heterogeneous catalysts for the coupling reactions between halogenated propylene oxides and CO2 to give the corresponding cyclic carbonates. The reaction conditions, substrate and catalyst scope, and mechanistic features of this catalytic transformation were investigated. High products yields (up to 98%), elevated TONs (up to 3920) or TOFs (up to 326 h-1) were attained under mild reaction conditions. In addition, catalyst 6 can be recycled at least eight times with no loss of catalytic activity.