Dong Tongfeng, Zheng Yu-Jia, Yang Guan-Wen, Zhang Yao-Yao, Li Bo, Wu Guang-Peng
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science & Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.
College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036, P. R. China.
ChemSusChem. 2020 Aug 21;13(16):4121-4127. doi: 10.1002/cssc.202001117. Epub 2020 Jul 30.
The development of solvent-free, metal-free, recyclable organic catalysts is required for the current chemical fixation of carbon dioxide converted into cyclic carbonates. With the goal of reducing the cost, time, and energy consumption for the coupling reaction of CO and epoxides, a series of highly active heterogeneous catalysts, based on a thiourea and quaternary ammonium salt system, are synthesized by using a thiol-ene click reaction under ultraviolet light. Benefitting from synergistic interactions of the electrophilic center (thiourea) and the nucleophilic site (ammonium bromide), the catalysts exhibit excellent catalytic selectivity (99 %) for the cycloaddition of carbon dioxide with a diverse range of epoxides under mild conditions (1.2 MPa, 100 °C). Moreover, the catalyst can be easily recycled by facile filtration and reused for 5 times without noticeable loss of activity and selectivity. This work provides a potential heterogeneous catalyst for the conversion of carbon dioxide into high value-added chemicals with the combined advantages of low cost, easy recovery, and satisfactory catalytic properties.
当前将二氧化碳化学固定转化为环状碳酸酯需要开发无溶剂、无金属、可回收的有机催化剂。为了降低一氧化碳与环氧化物偶联反应的成本、时间和能耗，通过在紫外光下使用硫醇-烯点击反应，合成了一系列基于硫脲和季铵盐体系的高活性多相催化剂。得益于亲电中心（硫脲）和亲核位点（溴化铵）的协同相互作用，这些催化剂在温和条件（1.2 MPa，100 °C）下对二氧化碳与多种环氧化物的环加成反应表现出优异的催化选择性（99 %）。此外，通过简单过滤即可轻松回收催化剂，并可重复使用5次，而活性和选择性没有明显损失。这项工作提供了一种潜在的多相催化剂，具有低成本、易于回收和令人满意的催化性能等综合优势，可用于将二氧化碳转化为高附加值化学品。
