【作者】 肖立伟；

【导师】 孙文华； 曹小平；

【作者基本信息】 兰州大学 ， 有机化学， 2009， 博士

【摘要】 本文立足于新型乙烯齐聚和聚合过渡金属配合物催化剂的设计与合成，成功合成了N^N^N三齿配体2-（1H-2-苯并咪唑）-6-亚胺吡啶及其铁、钴、镍配合物．在适当的助催化剂作用下，这些配合物表现出很高的催化活性．详细阐述了配体上取代基的电子效应、位阻效应等因素与催化行为的相互关系，系统研究了各种聚合反应参数（如温度、Al/M摩尔比、压力等）对乙烯催化活性的影响．同时合成了2-取代-1，10-菲啰啉的锰、钴和镍配合物，深入探讨了反应条件对产物的影响，研究了它们对乙烯齐聚的催化作用．论文包括四个部分：第一章综述了乙烯聚合和齐聚催化剂的研究进展，重点介绍了几类重要的过渡金属催化剂的发展情况．第二章合成并表征了一系列N^N^N三齿配体及相应的铁（Ⅱ）和钴（Ⅱ）二氯代配合物．配合物2-5c和2-6b的单晶结构表现为五配位变形的三角双锥构型；由于溶剂的配位，2-6d的晶体结构表现为六配位变形的八面体构型．以MAO或MMAO为助催化剂，铁催化剂表现出很高的齐聚催化活性和中等的聚合活性，钴催化剂表现出中等的齐聚活性．探讨了各种反应条件和不同的取代基对催化行为的影响，配体芳环上连有大位阻的异丙基的铁催化剂活性最高．与前面报道的苯并咪唑上烷基取代的同系列铁配合物相比，该体系催化活性更高．第三章合成了并表征了一系列N^N^N三齿镍（Ⅱ）配合物．由于与溶剂分子发生了配位，中心镍原子为六配位，配合物3-1a，3-1d和3-2c的单晶结构均表现为变形的八面体构型．在Et₂AlCl活化下，所有镍系催化剂均表现出很高的乙烯齐聚活性，齐聚物主要为二聚体和少量三聚体，研究了位阻效应和电子效应以及其他因素对乙烯催化行为的影响．与前面报道的苯并咪唑上烷基取代的同系列镍配合物相比，该体系催化活性更高．第四章利用2-氰基-1，10-菲啰啉和金属氯化物在醇中作用合成了的烷氧基亚胺取代的菲啰啉锰（Ⅱ）、钴（Ⅱ）和镍（Ⅱ）配合物，利用X-射线衍射进一步研究了一些配合物分子结构．其中2-甲氧基亚胺-1，10-菲啰啉金属配合物表现为中心对称的双中心结构，而乙氧基亚胺邻菲啰啉配合物则为单核结构．同样的原料如果在非质子溶剂中作用则会得到4-氰基-1，10-菲啰啉金属配合物，其结构为金属与两个配体和两个氯原子配位．采用有机铝化合物为助催化剂，研究了所得配合物的乙烯齐聚性质．结果表明，锰配合物活性很低，钴配合物表现出中等活性，而镍配合物具有相对较好的活性．更多还原

【Abstract】 This dissertation focuses on designing and synthesis of transition metalcomplexes as catalysts for ethylene activation. 2-（1H-2-benzimidazolyl）-6-[1-（arylimino） ethyl]pyridines ligands and their corresponding iron, cobalt and nickelcomplexes were successfully prepared. Upon activation with aluminum compounds,these complexes are active for ethylene oligomerization and/or polymerization. Therelationship between ligand environment and catalytic activity were elucidated.Additionally, the reaction parameters, such as the reaction temperature, cocatalyst, theamount of cocatalyst and ethylene pressure etc were systemically studied. Manganese,cobalt and nickel complexes bearing 1,10-phenanthroline derivatives have beensynthesized and characterized, the relation between the products and reactionconditions have been studied, their catalytic behavors upon oligomerization ofethylene have been elucidated. Four main parts are included in this dissertation.First in Chapterl,the progress of catalysts used in polymerization and /oroligomerization of ethylene is summarized, especially transition metal complexes.In chapter 2, a series of tridentate N^N^N iron（Ⅱ） and cobalt（Ⅱ） dichloridecomplexes bearing 2-（1H-2-benzimidazolyl）-6-[1-（arylimino）ethyl]pyridines weresynthesized and characterized. Single crystal X-ray diffraction studies ofrepresentative examples of the cobalt and iron complexes confirm distortedbipyramidal geometry around the metal center. Upon coordination of a methanolsolvent molecule a geometry change to a distorted octahedron has been observed. Thesteric and electronic effects on catalytic activity are evaluated for differentsubstituents in the arylimino part of the ligand. On treatment with MAO or MMAO,the iron （Ⅱ） complexes exhibited good activities of up to 10⁶ g·mol^-1（Fe）·h^-1 forethylene oligomerization and moderate activities for polymerization, meanwhilecobalt （Ⅱ） complexes showed moderate activities for ethylene dimerization. The bestactivities were observed with iron complexes with bulky iPr groups in the aryl moiety.In comparison to the analogues containing2-（1-alkyl-2-benzimidazolyl）-6-[1-（arylimino）ethyl]pyridines, the iron complexesbearing 2-（1H-2-benzimidazolyl）-6-1-（arylimino）ethyl)pyridines showed betteractivity towards ethylene reactivity.In Chapter 3, a series of tridentate N^N^N nickel complexes bearing 2-（1H-2-benzimidazolyl）-6-[1-（arylimino）ethyl]pyridines was synthesized and characterized. The molecular structures of complexes 3-1a, 3-1d and 3-2c were determined with thesingle crystal diffraction, and these were found to have six coordinate distortedoctahedral geometry around the Ni center. On treatment with Et₂AlCl, all nickelcomplexes exhibited good catalytic activities up to 10⁶ g·mol^-1（Ni）·h^-1 for ethyleneoligomerization with major dimerization. The steric and electronic effects on catalyticactivities of metal complexes as well as the influence of various reaction parameterswere carefully investigated.In Chapter 4, the methyl and ethyl carboxyimidate complexes of manganese,cobalt and nickel have been synthesized by the reaction of 2-cyano-1,10-phenanthroline with metal dichloride in the corresponding alcohol. Somecomplexes have been confirmed by single crystal X-ray diffraction analysis. Themolecular structures of methoxyimidate complexes demonstrate a centrosymmetricdimeric structure, whereas the ethoxyimidate complexes are mononuclear. Moreover,the reaction in non-protonic solvent resulted in the formation of nitrile metalcomplexes, in which the metal center was coordinated by two ligands and twochlorides. All the complexes were evaluated in the catalytic oligomerization ofethylene with alkylaluminums as cocatalyst. Manganese complexes were less active,cobalt complexes showed low to moderate catalytic activities, and nickel complexesgave moderate to good catalytic activities.更多还原