【作者】 李伟；

【导师】 刘滇生； 白生弟；

【作者基本信息】 山西大学 ， 无机化学， 2017， 博士

【摘要】 本论文涉及的工作是基于新型的限制几何构型(CGC)的含氮多齿配体化合物展开的,主要有:含苯基和SiMe3取代基的二胺、乙撑桥联的混合脒基-胺基化合物和丙撑桥联的混合脒基-胺基化合物。主要研究内容是:配体的合成,配体与无水过渡金属氯化盐或后过渡金属氯化盐的反应;对得到的一系列金属有机化合物进行结构表征;将所得IVB族金属有机化合物进行催化乙烯聚合性能研究;还研究了铁(钴)金属有机化合物的顺磁性。具体内容如下:第一章:导论——概述了与本论文研究内容有关的研究背景,包括:(1)几种重要的金属有机化合物的发展以及它们在有机合成和催化中的应用及发展研究;(2)限定几何构型(CGC)催化剂及其在烯烃聚合中的催化研究。第二章:合成了三种含SiMe3和Ph取代基的二胺配体(2a,2b,L1),以及三种碳链桥联的混合脒基-胺基配体化合物(L2,L3和L4),并通过X-ray、NMR和元素分析等对其结构进行了表征。第三章:以配体L1,L2为起始原料,分别与无水ZrCl4反应,合成了锆化合物3a-3d(Scheme 2,Scheme 3),并通过X-ray、NMR和元素分析等对其结构进行表征。在助催化剂MAO作用下,所得锆金属化合物3b对乙烯聚合的催化活性最高,为4.86×105 g PE mol-1(Zr)h-1。以配体化合物2a为起始原料,分别与ZrCl4和TiCl4(THF)2反应,合成了锆化合物3e和钛化合物3f(Scheme 4),也通过X-ray、NMR和元素分析等对其结构进行了表征。第四章:以配体L3为起始原料,分别与IVB族金属氯化物以及无水FeCl2反应,合成了IVB族金属化合物4a-4c以及亚铁化合物4d(Scheme 5)。还以配体2b为起始原料,与无水FeCl2反应合成了铁化合物4e,并通过X-ray、NMR和元素分析等对所得金属化合物结构进行了表征。在助催化剂MAO作用下,所得钛金属化合物4a对乙烯聚合的催化活性最高,为1.784×105 g PE mol-1(Ti)h-1,并且所得聚合物为具有超高分子量的高晶态、高线性聚乙烯。在室温下,顺磁性铁化合物4d(FeII)和4e(FeIII)的磁化率随磁场强度的变化呈“S”曲线,这表明二者都是超顺磁性物质。第五章:以配体2a为起始原料,与无水MCl2(M=Fe,Co,Ni)反应合成了后过渡金属化合物5a,5c,5d(Scheme 7);以配体L2为起始原料,与无水Fe Cl2反应,合成了亚铁化合物5b(Scheme 8),并通过元素分析对所得金属化合物结构进行表征。在室温下,顺磁性后过渡金属化合物5a-5c的磁化率随磁场强度的变化呈“S”曲线,这表明5a-5c都是超顺磁性物质。在氯化合物5d中,氯化镍催化了碳碳偶联,并形成两个五元杂环桥联的新结构,镍化合物中生成了为桥联杂环化合物的合成提供新方法及新思路。更多还原

【Abstract】 This dissertation focuses on the designing and synthesis of multi-dentate nitrogen-centered ligands(trimethylsilyl and phenyl substituted diamine,carbon linked amidinate-amido)and corresponding transition compounds.The structures of the obtained new compounds were characterized by X-ray,elemental analysis and 1H,13C-NMR.In addition,the synthesized group 4 metal compounds were used as catalysts for the olefin polymerization reaction in the presence of cocatalysts such as methylaluminoxane(MAO).Moreover,the synthesized post transition metal compounds were determined at 298 K using Lake Shore VSM 7307 magnetometer.Five main parts are included in this dissertation:Part 1: Some study content and background related to the main study of this paper.It is divided into two parts:(1)important organometallic compounds in organic synthesis and catalysis;(2)the constrained geometry compounds(CGC)as catalyst for the oligmerization and polymerization of olefins.Part 2: A group of multi-dentate nitrogen-centered ligands(trimethylsilyl and phenyl substituted diamine,carbon linked amidinate-amido)were synthesized and characterized by X-ray,NMR and elemental analysis(Scheme 1).Part 3: A series of zirconium compounds 3a-3d were prepared by the zirconium chlorides ZrCl4 reacted with ligands L1 and L2(Schemes 2 and 3).And zirconium complex 3e and titanium complex 3f(Scheme 4)were synthesized and all metal compounds were characterized by X-ray,NMR and elemental analysis.The influences of various catalytic systems formed from 3a-3d in the presence of a cocatalyst such as methylaluminoxane(MAO)on ethylene activation were evaluated.It was found that the catalytic activities of these zirconium complexes toward ethylene polymerization were closely related to bonding patterns(η3:η1,η3 or η1),the number of chlorine in procatalysts and the availability of the coordination site in the molecule.Zirconium trichloride complex 3b showed the highest catalytic activities because of its η1 bonding pattern.Procatalysts 3b and 3c showed good activity toward ethylene polymerization(up to 4.86 × 105 g PE mol-1(Zr)h-1),producing polymers with high molecular weights and broad molecular distributions.All the melting points of the resultant polyethylene are within relatively narrow ranges and higher than 132 °C,which indicates the formation of high-density polyethylene(HDPE).DSC,1H-NMR and 13C-NMR studies indicated that the polyethylene produced is highly crystalline and highly linear.More importantly,the current zirconium procatalysts showed excellent thermal stability at 70 °C,suitable for meeting industrial requirement.Part 4: A series of metal compounds 4a-4e were prepared by the Group metal chlorides MCl4(M = Ti,Zr,Hf)or FeCl2 reacted with ligand L3(Scheme 5 and Scheme 6).All metal compounds were characterized by X-ray and elemental analysis.And metal complexes 4a-4d were also characterized by 1H,13C-NMR.The pro-catalysts 4a-4c were screened for ethylene polymerization and titanium compound 4a exhibited good activity toward(up to 1.784 × 105 g mol-1(Ti)h-1),producing polymers with high molecular weights,broad molecular distributions and relatively narrow ranges and higher than 132 °C,which indicates the formation of high-density polyethylene(HDPE).More importantly,the current titanium procatalyst showed excellent thermal stability at 80 °C regarding the aspect of industrial requirement.The magnetic properties of complexes 4d and 4e in the form of magnetization versus magnetic field plot showed the curves of Type-S,illustrating that complexes 4d and 4e are superparamagnetic.Part 5: A series of late transition metal compounds 5a-5d were prepared by the late transition metal chlorides MCl2(M = Fe,Co,Ni)or FeCl2 reacted with ligand L2(Schemes 7 and 8).All metal complexes were characterized by X-ray and elemental analysis.The magnetic properties of complexes 5a-5c in the form of magnetization versus magnetic field plot showed the curves of Type-S,illustrating that late transition metal complexes 5a-5c are superparamagnetic.In nickel complex 5d,an unanticipated methylene-bridged bis(distorted five-membered heterocycle)compound,as an interesting C-C coupling reaction product.It was proposed that this coupling reaction was accelerated by the addition of NiCl2.更多还原