【作者】 职慧珍；

【导师】 吕春绪； 罗军；

【作者基本信息】 南京理工大学 ， 化学工程与技术， 2009， 博士

【摘要】 催化剂的高效分离和回收利用问题一直以来是绿色化学研究的重点内容之一。而具有“高温均相、低温两相”性质的催化体系,因其能有效结合均相催化体系反应高效与非均相催化体系催化剂易回收的优点已成为研究热点。因具有“高温均相、低温两相”功能的离子液体温控两相体系具有相间传质效果好、产品易分离等优点,相对于其它离子液体而言,是一种更为理想的反应体系,因此,加强此方面的研究必将为离子液体的深入研究和绿色化学的进一步发展提供重要参考。本论文设计并合成了7种新型的聚乙二醇型双子离子液体,其中包括5种聚乙二醇型中性双子离子液体(PEG₂₀₀-DIL、PEG₄₀₀-DIL、PEG₁₀₀₀-DIL、PEG₂₀₀₀-DIL、PEG₄₀₀₀-DIL)和2种聚乙二醇型酸性双子离子液体(PEG₂₀₀-DAIL、PEG₁₀₀₀-DAIL),同时还得到了两种优良的温控两相体系:PEG₁₀₀₀-DAIL/甲苯温控两相体系和PEG₁₀₀₀-DIL/甲苯温控两相体系。并详细考察了其中部分离子液体以及所得到的两种温控两相体系在一些有机单元反应中的应用情况。研究发现,PEG₁₀₀₀-DIL和PEG₁₀₀₀-DAIL均可作为溶剂使用,而PEG₁₀₀₀-DAIL在反应中不但可以作为溶剂,还可作为催化剂使用。本研究工作分别将PEG₁₀₀₀-DAIL/甲苯温控两相体系应用于芳香醛的缩醛反应、芳香酸的酯化反应、芳香醛的三组分缩合反应及Biginelli反应和将PEG₁₀₀₀-DIL/甲苯温控两相体系应用于对甲苯磺酸催化的缩醛反应及氢氧化氧铁催化的硝基还原反应。并分别考察了温度、时间、原料配比以及催化剂重复使用等因素对上述反应的影响。研究结果表明,两种体系对上述反应具有广泛的适用性,且具有反应时间短、产率高、产品分离简单、催化剂重复使用性能优良、离子液体流失量小等优点。其中PEG₁₀₀₀-DAIL/甲苯体系还克服了因离子液体黏度高而造成的与固体产品难分离的缺点,分离过程中避免了使用大量有机溶剂,同时还简化了固体产品与高黏度离子液体的分离步骤。本论文还考察了PEG₂₀₀-DAIL在甲苯硝化与DPT硝解反应中的应用情况。研究结果表明,加入PEG₂₀₀-DAIL,能使甲苯硝化的o/p值降至1.12,且在N₂O₅与PEG₂₀₀-DAIL的协同作用下,大量减少了DPT硝解反应中浓硝酸的用量,并使产率提高到64%。另外,研究中也发现PEG₁₀₀₀-DIL还能与水形成“高温分相、低温均相”的温控体系,将该体系在常温条件下应用于Knoevenagel缩合反应中,只需几分钟就能得到60%-99%的产率,且PEG₁₀₀₀-DIL可以通过简单分液而不是蒸馏的方式回收,操作简单且能耗低。总之,本论文合成的这类聚乙二醇型双子离子液体,合成简单,且能与甲苯和水形成温控两相体系,离子液体可同时作为溶剂和催化剂使用,并能有效回收,多次重复使用后还能有效保持催化活性,损失量小。实现了均相催化和非均相催化优点的有效结合,为有机化学提供了一种新的温控两相催化反应一分离耦合体系。更多还原

【Abstract】 Separation and recovery of catalyst with high efficiency plays an important role in green chemistry. New catalytic system possess the thermoregulated biphasic behavior of "mono-phase under high temperature, bi-phase under room temperature" have been attracted much attention due to their advantages of both homogeneous and heterogeneous catalysis with high product yield and the easy separation of product from catalytic system. ILs, as environmental friendly reaction media or catalysis, have attracted increasing attention. And, ionic liquids based on the thermoregulated biphasic behavior have been proposed because of their obvious advantages. In this paper, PEG-DIL and PEG-DAIL have been studied. PEG-1000-based dicationic ionic liquid (PEG₁₀₀₀-DAIL, PEG₁₀₀₀-DIL) exhibiting temperature-dependent phase behavior with toluene （water） and their applications in different organic reactions were studied.Five new neutral PEG-based dicationic ionic liquids (PEG₂₀₀-DIL, PEG₄₀₀-DIL, PEG₁₀₀₀-DIL, PEG₂₀₀₀-DIL, PEG₄₀₀₀-DIL) and two new acidic PEG-based dicationic ionic liquids (PEG₂₀₀-DAIL, PEG₁₀₀₀-DAIL) were synthesized. It was found that PEG₁₀₀₀-DAIL/ toluene system and PEG₁₀₀₀-DIL/toluene system could be formed excellent thermoregulated biphasic system. And PEG₁₀₀₀-DIL/water could be formed "mono-phase under room temperature, bi-phase under high temperature" system. Moreover, PEG₁₀₀₀-DAIL could be used as both solvent and catalyst. Applications of PEG₁₀₀₀-DAIL/toluene thermoregulated system in acetalizations, esterifications, one-pot three-component condensations and Biginelli reactions were investigated. PEG₁₀₀₀-DIL acted as solvent for acetalizations （p-toluenesulfonic acid as catalyst） and nitro-group reduction （FeOOH as catalyst） in PEG₁₀₀₀-DIL/toluene system. And applications of PEG₁₀₀₀-DIL/water system in Knoevenagel reaction and PEG₂₀₀-DAIL in nitration of toluene and nitrolysis of DPT were investigated also. Efects of reaction temperature, reaction time, amount of calalyst, and ratio of raw materials on these reactions were investigated. It was found that these reactions had advantages such as, short reaction time, high yields, easy separation without any apparent loss of catalytic activity and little loss of weight even after more times recycling.PEG-based ionic liquids were developed. Novel "mono-phase under high temperature, bi-phase under room temperature" systems (PEG₁₀₀₀-DAIL/toluene system and PEG₁₀₀₀-DIL/toluene system) and "mono-phase under room temperature, bi-phase under high temperature" system (PEG₁₀₀₀-DIL/water system) have been found highly effective for some organic reactions.更多还原