【作者】 霍平；

【导师】 陈义旺； 贺晓慧；

【作者基本信息】 南昌大学 ， 材料物理与化学， 2014， 博士

【摘要】 本文设计合成出一系列不同芳环取代基的三维立体α-二亚胺镍配合物C1-C4(其中，芳环：C1,2,6-二甲基苯基；C2,2,6-二异丙基苯基；C3,2,4,6-三甲基苯基；C4,2,6-二甲基-4-溴苯基)。所有配合物均通过单晶X射线衍射测定其晶体结构，这四种镍的配合物中，C1、C3和C4的晶体结构基本类似，均为单核四配位结构。而芳环取代基为异丙基C2的晶体结构是双金属中心五配位的配合物且两个金属中心镍与两个溴原子形成了一个平面四元环。在B(C6F5)3为助催化剂下，三维立体α-二亚胺镍配合物C1-C4催化降冰片烯(NB)均聚和NB与5-降冰片烯-2-乙酸酯(NB-OCOCH3)不同比例共聚时都呈现出较高的活性(107gpolymer/molNi·h)。四类配合物催化活性大小为：C2>C3>C1>C4，这一规律说明催化剂的空间效应和电子效应对于催化剂活性有一定的影响，芳环取代基位阻越大，活性越大；芳环取代基给电子能力越强，活性越大。通过Kelen-Tüd s法计算得到单体竞聚率分别为rNB OCOCH3=0.05，rNB=6.72。此外，聚合物末端为基团C6F5可以推导出C1-C4/B(C6F5)3催化体系催化聚合的活化机理：金属卤素键即Ni-Br键打开，C6F5从硼化物上转移到金属镍上。这一结论同时也通过密度泛函理论得到证实。前线分子轨道理论分析，催化剂与降冰片烯的能级相互作用对于催化剂催化活性起着非常关键的影响，计算表明：催化剂的最低未占有分子轨道(LUMO)能级与降冰片烯的最高占有分子轨道(HOMO)能级相差越小，其活性就越大。运用相似的合成方式，还设计合成出六类不同芳环取代基的三维立体α-二亚胺钯配合物C5-C10(其中,芳环：C5,2,6-二甲基苯基；C6,2,6-二异丙基苯基；C7,2,4,6-三甲基苯基；C8,2,6-二甲基-4-溴苯基；C9,4-氯苯基；C10,4-三氟甲基苯基）。α-二亚胺钯配合物C5、C7和C9的晶体结构中，金属中心钯与配体形成四方平面的配位结构，在配位平面内键长、键角均在这种配位方式标准范围之内。这三种配合物的两个苯胺结构几乎垂直于五元环的配位平面，对于具有大位阻的空间立体骨架结构没有任何排斥作用。采用C5-C10/B(C6F5)3体系催化降冰片烯与5-降冰片烯-2-羧酸甲酯(NB-COOCH3)共聚合呈现较高的催化活性(105gpolymer/molPd·h)。三维立体骨架结构的引入，能够有效提高钯配合物的稳定性，催化活性及极性单体插入率。详细地考察了芳环上取代基对于钯配合物催化活性的影响，芳环上具有大位阻或者强给电子基团的配合物具有较高的催化活性。聚合物碳谱和氢谱分析表明其末端基团为甲基，证实了金属卤素键即Pd-Cl键能够被B(C6F5)3活化，Pd-Cl断裂，形成活性中心，从而引发聚合。催化剂负载化是一种改善催化剂稳定性和制备功能化纳米环烯烃聚合物材料的有效方法，本文还设计合成出带有羟基的三维立体α-二亚胺镍配合物(C11)和钯配合物(C12)，分别利用其羟基与三甲基铝活化的多壁碳纳米管(Me3Al/MWNTs)通过化学键进行键合，形成多壁碳纳米管负载镍、钯催化剂(C11/Me3Al/MWNTs和C12/Me3Al/MWNTs)。由于多壁碳纳米管的大比表面积和良好的热质传递作用，相比C11、C12和多壁碳纳米管物理掺杂的三维立体α-二亚胺镍、钯配合物(C11@MWNTs和C12@MWNTs)，C11/Me3Al/MWNTs和C12/Me3Al/MWNTs对于降冰片烯均聚和降冰片烯与甲基丙烯酸正丁酯的共聚呈现出较高的催化活性和产率。除此之外，多壁碳纳米管负载镍催化剂C11/Me3Al/MWNTs催化所得纳米复合聚合物中，碳纳米管分散均匀，并且机械性能也得到加强。聚降冰片烯的功能化一直是扩大降冰片烯应用前景的有效途径。设计合成出两类新型苯并降冰片烯衍生物单体(OAc)2BenzoNBD和(OCH2PhBr)2-BenzoNBD，在甲苯中采用C2/B(C6F5)3分别对其与5-降冰片烯-2-亚甲基丁基醚进行共聚合研究，催化活性达到3.2×104gpolymer/molNi·h。苯并降冰片烯衍生物在共聚物中具有非常高的插入率，当苯并降冰片烯衍生物(OAc)2BenzoNBD和(OCH2PhBr)2BenzoNBD加入摩尔比为10-50%时，其插入率分别为9.1-26.7%和9.7-30.4%。该聚合物具有很好的热稳定性，玻璃化转变温度和透光率。能够通过溶液成膜和静电纺丝技术进行加工处理，采用溶液成膜法制备的共聚物薄膜在可见光范围具有良好透光性，静电纺丝技术制备的聚合物纤维表面光滑，直径约700-1200nm。更多还原

【Abstract】 In this paper, a series of novel three-dimensional geometry9,10-dihydro-9,10-ethanoanthracene-11,12-diimine nickel complexes with different aryl substituentsC1-C4(Aryl: C1,2,6-dimethylphenyl; C2,2,6-diisopropylphenyl; C3,2,4,6-trimethylphenyl; C4,2,6-dimethyl-4-bromophenyl) were synthesized. The solid-statestructures of all complexes had been determined by single crystal X ray diffractions.In these complexes, the coordination geometries of the complexes C1, C3and C4were demonstrated to be very similar in the solid state. They were both mononuclearand four-coordinate. However, the crystal structure of C2showed a binuclearcomplex, where each nickel atom is five-coordinate. The two nickel atoms togetherwith two bromine atoms form planar four-membered ring.The nickel complexes C1-C4, with three-dimensional geometry, exhibited veryhigh activities for norbornene (NB) homopolymerization with only B(C6F5)3ascocatalyst(107gpolymer/molNi·h). To investigate whether they also had high activitiestoward copolymerization of NB and5-norbornene-2-yl acetate(NB-OCOCH3),complexes C2and C3were selected for copolymerization of NB and NB-OCOCH3inrelatively high activities. Comparing the activities with structures of catalysts, it couldbe found that the activities were following the law: C2>C3>C1>C4. The activitieswere affected remarkably by bulky effect and electronic effect, larger steric hindranceand stronger electron-donating effect of substituents around the aryl in the ligandcould increase the activities. The reactivity ratios of the NB and NB-OCOCH3monomers for C2/B(C6F5)3system by the Kelen-Tüd s method were determined toberNB OCOCH3=0.05and rNB=6.72, respectively. Moreover, the mechanism ofpolymerization catalyzed by the novel three-dimensional geometry nickel(II)complexes was presented and supported by the end group analysis of the polymer anddensity functional theory (DFT) calculation of the reaction. The substituent effect ofthe catalysts and the interaction between Ni2+and NB were discussed, and the resultsshowed that α-diimine nickel complexes with smaller HOMO–LUMO gap couldachieve higher reactivity. Six three-dimensional geometry9,10-dihydro-9,10-ethanoanthracene-11,12-diimine methyl palladium chloride complexes C5-C10with different aryl substituents(Aryl: C5,2,6-dimethylphenyl; C6,2,6-diisopropylphenyl; C7,2,4,6-trimethylphenyl; C8,2,6-dimethyl-4-bromophenyl; C9,4-chlorophenyl; C10,4-trifluoromethylphenyl) were synthesized and characterized. The solid-state structuresof palladium complexes C5, C7and C9had been determined by single crystal X raydiffractions. They featured a square-planar coordination of the central metal. Thebond angles and distances in the palladium coordination plane were within thestandard range for these types of complexes. Two aniline moieties of C5, C7and C9were nearly perpendicular to the five-membered coordination plane, showing noobviously repulsive interactions between the aniline moiety and backbonesubstituents.The catalytic system C5-C10/B(C6F5)3exhibited high activities(105gpolymer/molPd·h) in the homopolymeization of norbornene and copolymerization ofnorbornene with5-norbornene-2-carboxylic acid methyl ester. Introduction ofthree-dimensional geometry on the backbone of palladium complexes couldeffectively improve their thermal stability and afford high incorporation of polarmonomer. The α-diimine palladium complexes with big steric hindrance or stronglyelectron-donating on the aryl ring of ligand could achieve higher reactivities.Moreover, The13C NMR and1H NMR analysis of polymer revealed that the bond ofpalladium-halogen of complexes could be effectively activated by B(C6F5)3.Supported catalyst was an effective method that increased the catalysts’ stabilityand prepared polyolefin nanocomposite materials. The covalently immobilizedmultiwalled carbon nanotubes(MWNTs) supported three-dimensional geometryα-diimine nickel, palladium catalysts(C11/Me3Al/MWNTs and C12/Me3Al/MWNTs)were prepared by corresponding α-diimine nickel(C11), palladium(C12) complexesand Me3Al activated MWNTs(Me3Al/MWNTs). Compared with C11, C12andphysical mixing of nickel, palladium catalysts with MWNTs(C11@MWNTs andC12@MWNTs), C11/Me3Al/MWNTs and C12/Me3Al/MWNTs showed improvedactivity and productivity in norbornene homopolymerization and copolymerizationwith polar monomer. The morphology of the resulting polymers obtained from C11/Me3Al/MWNTs revealed that the MWNTs were dispersed uniformly in polymerand wrapped by polymers to squeeze out of spherical particles, leading to theenhanced processability and mechanical properties.The functionalization of polynorbornene was proved to be an effective strategyto expand its application prospect. Two novel benzonorbornadiene derivatives(OAc)2BenzoNBD and (OCH2PhBr)2BenzoNBD monomers were synthesized andused to copolymerization with2-butoxymethylene norbornene(BN) by the catalyticsystem of C2/B(C6F5)3in toluene, respectively. The (OCH2PhBr)2BenzoNBD or(OAc)2BenzoNBD content in the copolymers could be controlled up to9.1-26.7%or9.7-30.4%by varying the comonomer feed ratios (OCH2PhBr)2BenzoNBD or(OAc)2BenzoNBD from10%to50%. The BN/(OCH2PhBr)2BenzoNBD copolymersand BN/(OAc)2BenzoNBD copolymers exhibited high thermal stability and highglass transition temperature, together with excellent optical transparency. Copolymerswere processed into films and fibers by solution casting method and electrospinning.The films showed good transparency in the visible region, the fibers were uniformand their surfaces were reasonably smooth, with the average diameters of fibersranging from700to1200nm.更多还原