Regulation of Novel Multi‐Center Ionic Liquids for Synergetically Catalyzing CO 2 Conversion into Cyclic Carbonates
Regulation of Novel Multi‐Center Ionic Liquids for Synergetically Catalyzing CO 2 Conversion into Cyclic Carbonates
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DOI：
10.1002/slct.202101172
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发表时间：
2021-07
期刊：
影响因子：
2.1
通讯作者：
Jie Chang;Yitao Liu;Qian Su;Lei Liu;Lili Deng;Ting Ying;Li Dong;Zhibin Luo;Qian Li
中科院分区：
文献类型：
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作者：
Jie Chang;Yitao Liu;Qian Su;Lei Liu;Lili Deng;Ting Ying;Li Dong;Zhibin Luo;Qian Li
以CO2高效转化为环状碳酸酯为目标，设计了一类新型多中心离子液体（ILs）.在环加成反应中，多中心结构比单中心结构能暴露更多的活性中心。在这些离子液体中，采用链调节策略，多中心六丁基咪唑溴苯（BIM-6）表现出95%环氧丙烷（PO）转化率和99%选择性的性能（130 °C，2.5 MPa，离子液体量0.15 mol%，1 h）。 此外，多中心IL在5次循环后显示出良好的可重复使用性，并广泛适用于不同的末端环氧化物。密度泛函理论（DFT）和非共价相互作用（NCI）表明，多中心离子液体与环氧化物之间形成了氢键，加上侧链长度的阻碍，使溴离子游离，协同活化反应物。由此提出了基于氢键诱导和位阻调控的可能机制。该研究为绿色化工过程中高效离子液体的开发提供了新的途径。
A family of novel multi‐center ionic liquids (ILs) were designed for the target of efficient transformation of CO2into cyclic carbonates. The multi‐center structures could expose more active sites than single‐center ones in cycloaddition reaction. Among these ILs, with the chain‐regulation strategy, the multi‐center hexabutylimidazole bromobenzene (BIM‐6) exhibited the performance with 95 % propylene epoxide (PO) conversion and 99 % selectivity (130 °C, 2.5 MPa, ILs amount 0.15 mol%, 1 h). Moreover, the multi‐center ILs showed good reusability after 5 cycles and extensive suitability for different terminal epoxides. Density functional theory (DFT) and noncovalent interactions (NCI) illustrated that hydrogen‐bond formed between the multi‐center ILs and epoxides, together with hindrance of side chain lengths setting bromide free, synergistically activated reactants. Thus, the possible mechanism based on hydrogen‐bond induction and hindrance regulation was proposed. This study provides a new approach for development of highly efficient ILs in the green chemical process.