1,1'-Methylenediimidazolium-Based Multiple Hydrogen-Bond Donor Catalysts Facilitate the Cycloaddition of CO_(2) with Epoxides under Atmospheric Pressure  

1,1'-亚甲基二咪唑鎓多氢键供体催化剂促进常压下CO_(2)与环氧化物的环加成反应

作　　者：Chen Xuewei Yu Fangcai Tian Chuanhong 陈学伟;于方彩;田传洪(湖南师范大学化学化工学院石化新材料与资源精细利用国家地方联合工程实验室、有机功能分子组装与应用湖南省重点实验室,长沙410081)

机构地区：[1]National and Local United Engineering Laboratory for New Petrochemical Materials and Fine Utilization of Resources,Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province,College of Chemistry and Chemical Engineering,Hunan Normal University,Changsha 410081

出　　处：《有机化学》2024年第10期3198-3205,共8页Chinese Journal of Organic Chemistry

基　　金：湖南省科技计划(No.2018TP1017)资助项目.

摘　　要：The quest for innovative hydrogen-bond donor(HBD)catalysts has led to a significant advancement in the field of organic synthesis.Considering the electron-withdrawing strength of imidazolium cations and the spatial requirements of hydrogen bond donors,a novel HBD catalyst based on the 1,1'-methylenediimidazolium scaffold by bridging two imidazolium cations with methylene was developed.The 1,1'-methylenediimidazolium-based catalysts exhibit excellent performance in the cycloaddition reaction of CO_(2) and epoxides,achieving up to 99% yield and 99%selectivity under mild conditions(atmospheric pressure,80℃ for 12 h,with 1 mol%catalyst).The geometric structure,atomic charge distribution,and synergistic effect of HBD catalysts were studied in detail through 1H NMR spectroscopy and density functional theory(DFT)calculations.The research results indicate that the protons at positions C2-H,C2'-H,C5-H,and C5'-H on the imidazolium rings,as well as the protons on the bridged methylene,contribute to the formation of multiple hydrogen bonds with appropriate distance and synergistic effects,which are crucial for activating CO_(2) and epoxides.This research highlights the distinctive attributes of 1,1'-methylenediimidazolium-based catalysts and offers valuable insights into the development of highly efficient multiple HBD catalysts.对新型氢键供体(HBD)催化剂的追求导致了其在有机合成领域的重大进展.考虑到咪唑阳离子的吸电子强度和氢键给体的空间要求,通过亚甲基桥接两个咪唑阳离子,发展了一种基于1,1'-亚甲基二咪唑鎓支架的新型HBD催化剂.这些催化剂在CO_(2)与环氧化物的环加成反应中表现出优异的性能,在温和的条件下(常压,80℃,12 h,1 mol%催化剂)获得了高达99%的产率和99%的选择性.通过1H NMR研究和密度泛函理论(DFT)计算,详细研究了催化剂的几何结构、原子电荷分布和多HBD协同效应.研究结果表明,咪唑鎓环上C2-H、C2'-H、C5-H、C5'-H位置的质子以及桥接的亚甲基上的质子,有助于形成具有适当距离和协同效应的多重氢键作用,这对活化二氧化碳和环氧化物至关重要.本研究突出了1,1'-亚甲基二咪唑鎓催化剂的独特特性,并为开发高效多重HBD催化剂提供了宝贵的经验.

关 键 词：1 1'-methylenediimidazolium multiple hydrogen-bond donor catalysts cycloaddition of CO_(2) cooperative effects density functional theory(DFT)calculation 

分 类 号：O621.251[理学—有机化学] O643.36[理学—化学]