分子筛负载氨基、羟基离子液体催化CO2和环氧丙烷合成碳酸丙烯酯

合成了含氨基、羟基的双功能团离子液体氯化1-(2-羟乙基)-3-氨基丙基咪唑和单氨基功能团离子液体氯化-1-胺-丙基-3-甲基咪唑。将离子液体(ILs)负载在介孔分子筛SBA-15上，考察其催化CO2和环氧丙烷(PO)合成碳酸丙烯酯(PC)的反应性能，并用核磁共振进行表征。结果表明，与单功能团离子液体相比，双功能团离子液体具有优良的催化效率，在反应温度373 K、反应压力1.8 MPa条件下，其催化CO2和环氧丙烷制备碳酸丙烯酯，PO的转化率和PC的选择性分别达到90.4%、92.5%。通过Gaussian 09软件DFT方法中的B3LYP/6-311+G(d,p)基组理论分析了ILs与PO的稳定结构、相互作用关系、结合键能、电荷分布、静电势能差、前沿轨道及位能差，计算结果表明离子液体上的官能团氨基、羟基与PO耦合产生氢键，由此推测了环加成反应机理。

Synthesis of Propylene CarbonateWith CO2 and Propylene Oxide Catalyzed by Amino and Hydroxyl Ionic Liquids Supported on Molecular Sieve

Bifunctional group ionic liquid chlorination 1-(2-ethoxy)-3-imidazolyl-propylamine containing amino and hydroxyl， and single amino functional group ionic liquid chlorination 1-amine propyl-3-methylimidazole were synthesized, respectively. The ionic liquids (ILs) were loaded on the mesoporous molecular sieve SBA-15, and their catalytical performance for the reaction of CO2 and propylene oxide (PO) to propylene carbonate (PC) were investigated. NMR was employed to characterize the catalysts in the above process. Experimental results indicated that, compared with singe functional group ILs, bifunctional group ILs had better catalytic efficiency. Under the conditions of temperature 373 K and pressure 1.8 MPa, PO conversion and PC selectivity could reach 90.4% and 92.5%, respectively. With applying Gaussian 09 software, density functional theory (DFT) was used to theoretically analyze the stable structure, interactive relationship, combination bond energy, charge distribution, electrostatic potential energy difference, frontier orbital of ILs and PO. Through above calculation, it can be found that the coupling of amino and hydroxyl on the functional group of ILs and PO can generate hydrogen bonds, and then possible cycloaddition reaction mechanism is proposed.