【作者】 吴玉锋；

【导师】 崔元臣；

【作者基本信息】 河南大学 ， 高分子化学与物理， 2009， 硕士

【摘要】 Heck反应和Suzuki反应是现代有机合成中形成C-C键的重要手段,近几十年来引起了人们的广泛关注。早期的Heck反应和Suzuki反应催化剂主要是PdCl₂、Pd（OAc）₂、Pd（PPh₃）₂Cl₂等均相催化剂,这类催化剂有较高的活性和选择性,但高温下稳定性差,反应后难与产物分离和重复利用,这些因素都严重的影响了其实际应用。国内外学者关于Heck反应和Suzuki反应的实际应用做了大量的研究工作,取得了不少成果。负载型非均相催化剂就是其中典型的成果之一,已报道的负载型非均相催化剂的载体主要有无机材料类、有机硅类和聚合物类等,这类催化剂有着良好的催化活性和选择性,并且反应条件温和以及反应结束后易于产物分离。近几年人们发现来源广泛、储量丰富、价廉易得、可生物降解、无毒的天然高分子作为催化剂的载体,制备负载型催化剂同样具有很高的催化活性、很好的选择性以及可重复利用性,对于其实际应用具有很重要的意义和良好的前景。本论文主要研究了木质素及其衍生物负载钯催化剂的制备、表征及其对Heck反应和Suzuki反应的催化性能。我们首先以木质素为载体,通过与PdCl₂作用制得了木质素负载钯催化剂,并用XPS、TG和DTA等手段对其进行了表征,XPS数据表明在木质素负载钯催化剂中起催化作用的是二价钯,热分析表明木质素负载钯催化剂具有较好的稳定性。这种催化剂在空气氛围中能催化丙烯酸与芳基碘的反应,生成取代的反式肉桂酸,产率达60.1%,并具有一定的重复使用性能。用交联剂甲醛对天然木质素进行交联处理,制得交联木质素,然后再与PdCl₂作用制得了交联木质素负载钯催化剂,对其进行了表征。与木质素负载钯催化剂相比,交联木质素负载钯催化剂具有更好的催化活性和重复使用性能。在空气氛围中、90℃下反应8h催化丙烯酸与碘苯的反应,产率高达100%,重复使用5次,产率仍高达90%。采用较温和的Mannich反应制得了多乙烯多胺/甲醛修饰的木质素-二乙烯三胺（Lignin-Diethylenetriamine）、木质素-三乙烯四胺（Lignin-Triethylenetetramine）和木质素-四乙烯五胺（Lignin-Tetraethylenepentamine）三种木质素胺载体。三种载体分别与PdCl₂作用制得了三种木质素胺负载钯催化剂,并用TG、DTA和XPS等对其进行了表征。结果表明,三种木质素胺负载钯催化剂均能很好的催化丙烯酸与芳基卤的Heck反应,特别是催化溴苯与丙烯酸的反应。其中木质素-四乙烯五胺负载钯催化剂在氮气氛围中（120℃,12h）催化丙烯酸与溴苯的反应,反式肉桂酸的产率高达94.5%,显示了较高的催化活性,制备的三种催化剂均有较好的重复使用性能。初步探讨了木质素-四乙烯五胺负载钯催化剂对碘苯和四苯硼钠的Suzuki反应的催化性能,结果表明,该催化剂对Suzuki反应也具有很好的催化活性,并具有一定的重复使用性能。如以DMF:H₂O为2 ml:1 ml时,NaHCO₃作为碱时,在80℃反应8 h产物产率高达90.2%。更多还原

【Abstract】 Heck reaction and Suzuki reaction were important tools in organic synthesis and have received considerable attention in recent years. The traditional catalysts of Heck reaction and Suzuki reaction are the homogeneous catalysts such as PdCl₂, Pd（OAc）₂ and Pd（PPh₃）₂Cl₂ complexes. Although these catalysts have high catalytic activity and Selectivity, they also have some disadvantages that it is hard to separate from products, unstable in high temperature etc, which were unfavorable to apply in industry. These problems can be overcome by supported and heterogeneous catalysts. The catalyst supports were often used by inorganic materials, silicone and polymer. The catalysts have high activity, selectivity, moderate reaction conditions and easily separated and recovered. The natural macromolecules supported catalysts were paid great attentions, because these natural macromolecules were easy to gain, abundant sources, innocuous, cheap and biodegradable. The natural macromolecules supported catalysts have the same high activity, selectivity, reusability and have good prospects in practical application.Lignin and its derivatives were used to support palladium chloride. Lignin and its derivatives supported palladium complexs were characterized by XPS, TG, DTA and were applied as heterogeneous catalysts for Heck reaction and Suzuki reaction. The date of XPS showed that the active center is divalent palladium in Lignin supported palladium catalyst. Thermal analysis showed that the Lignin supported palladium catalyst has good stability. It was found that the Heck reaction of acrylic acid with aryl iodide could be catalyzed by the catalyst at atmospheric condition. The yield of trans-Cinnamicacid is up to 60.1%, and the catalyst could be used for several times.Cross-linking Lignin complex was readily synthesized from natural Lignin and formaldehyde was used as a Cross-linking agent. The prepared complex was used as a matrix to support palladium chloride. Cross-linking Lignin supported palladium complex was characterized by XPS, TG and DTA. Compared with Lignin supported palladium complex, Cross-linking lignin supported palladium complex has better catalytic activity and recycle performance. Especially, It was found that the Heck reaction of acrylic acid with aryl iodide was obtained with a high yield of 100% at 90℃for 8h. The catalyst could be used for more than five times and a yield up to 90% was obtained in the fifth cycle.Three Lignin-amine complexes were readily synthesized from polyethylene-polyamine and formaldehyde by the mild Mannich reaction. These complexes supported palladium chloride catalysts were characterized by TG, DTA and XPS. The Heck reaction of acrylic acid with aryl halides could be efficiently catalyzed by the three catalysts. Especially, the Heck reaction of acrylic acid with aryl bromide was obtained with a high yield of 94.5% at 120℃for 12h in N₂ by the Lignin-TEPA supported palladium catalyst. Three Lignin-amine-Pd complexes could be easily separated and used repeatedly.Lignin-TEPA supported palladium was applied as a heterogeneous catalyst for Suzuki reaction of iodobenzene and sodiumtetraphenylboron. It was found that the catalyst has high catalytic activity and could be used for several times. The yield of the reaction was up to 90.2%, After it was performed at 80℃for 8 h in DMF/H₂O（vol 2:1） and NaHCO₃ was adopted as base.更多还原