Simple Preparation of Halogen-Substituted <i>α</i>-Diimine Nickel Complexes Immobilized into Clay Interlayer as Catalysts for Ethylene Oligo-/Polymerization

In the practical use for the production of the α-olefins, it is highly desired to develop a novel heterogeneous catalyst system. The metal complexes immobilized into the clay interlayers show a great potential as heterogeneous catalysts due to their excellent processability. In this study, nine types of heterogeneous procatalyst Ln/Ni2+-micas were synthesized via a one-pot preparation method, which includes both the condensation reaction of the ligand derivatives and the intercalation of the ligands into the Ni2+ ion-exchanged fluorotetrasilicic mica interlayer. The ligand structures of the prepared procatalysts were [Ln: R-N = C(Nap)-C(Nap) = N-R] [(Nap = 1,8-naphthdiyl) (L1, R = 2-MePh;L2, R = 2-FPh;L3, R = 2-BrPh;L4, R = 4-MePh;L5, R = 4-FPh;L6, R = 4-BrPh;L7, R = 2,4-F2Ph;L8, R = 2,4-Br2Ph;L9, R = 2,6-F2Ph). At 50℃ and 0.7 MPaethylene pressure, the triisobutylaluminum-activated L1-L6/Ni2+-mica showed a catalytic activity for the ethylene oligo-/polymerization in the range of 334 - 549 g-ethylene&bull;g-cat–1&bull;h–1. A high catalyst activity was obtained when the substituent having a larger steric bulk than that of a methyl substituent was introduced at the ortho-position of the aryl rings. The introduction of the fluorine substituent as a strong electron-withdrawing group to the para-position also increased the catalytic activity. The L2, L4, L5, and L6/Ni2+-micas showed moderate selectivities to oligomers consisting of C4-C20 in the range of 19.9 - 41.6 wt% at 50℃. The calculated Schulz-Flory constants α based on the mole fraction of C12 and C14 were within 0.61 - 0.78.

2-AMINOMETHYLPYRIDINE NICKEL(Ⅱ) COMPLEXES—SYNTHESIS,MOLECULAR STRUCTURE AND CATALYSIS OF ETHYLENE POLYMERIZATION

A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted in...

Synthesis, Structure and Norbornene Polymerization Catalyzed by Nickel(Ⅱ) Complex Bearing N,O-bis(1-(6-ethylpyridin-2-ylimino)-methylenyl)naphthalen-2-ol Ligand

The title complex bis{1-{[（6-ethyl-2-pyridinyl）imino]methylenyl}-2-naphthale- nolato-N,O}-nickel（lI） （C36H32NnO2Ni） has been synthesized by the reaction of l-{[（6-ethyl-2- pyridinyl）imino]methylenyl}-2-naphthalenol with Ni（CH3COO）2·4H2O, and characterized by IR spectrum, elemental analysis and TG. The complicated space structure has been confirmed by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 11.410（4）, b = 14.382（4）, c = 18.121（6） ,A, β = 97.147（6）% V= 2950.5（16）A3, C36H32N4O2Ni, Mr = 611.37, Z = 4, Dc = 1.376 g/cm3, μ = 0.698 mm-1 F（000） = 1280, the final R = 0.0519 and wR = 0.1493 （1 〉2σ（I））. This title compound was used as precatalysts for the polymerisation of norbornene. When activated with MAO, the complex exhibited excellent catalytic activity up to 1.98 × 107 g ofPNB （mol of Ni）-1 h-1 with high monomer conversion.

A Novel Phenoxyimine-based Schiff Base Ligand and Its Mononuclear Nickel(Ⅱ) Complex：Synthesis,Crystal Structure,Norbornene Polymerization and Catalytic Activity

A novel phenoxyimine-based Schiff base ligand and its mononuclear complex [C（58）H（52）N2NiO2]（L = 2-benzhydryl-4-dimethoxy-3,5-dimethyl-salicylaldehyde） has been synthesized and characterized by IR spectrum, elemental analysis, TG, WAXD spectra, ^1H NMR and ^（13）C NMR. In addition, the molecular structure has been measured by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 14.510（6）, b = 18.573（7）, c = 20.961（6） A, β = 123.453（19）°, V = 4713（3）A^3, Mr = 867.73, Z = 4, Dc = 1.223 g/cm^3, μ = 0.456 mm^-1, F（000） = 1832, the final R = 0.0685 and wR = 0.1758（I 〉 2σ（I））. The complex was used as homogeneous catalysis of polymerization of norbornene, and the MAO as cocatalyst. The nickel complex exhibited good catalytic activity up to 1.913 × 10^7 g of PNB（mol of Ni）^-1h^-1,and the yields of these reactions depend on the nature of the substituent in the aromatic ring.

Highly Active New α-Diimine Nickel Catalyst for Polymerization of Ethylene

A new α-diimine ligand 1a, bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2a, {bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene}dibromo- nickel were successfully synthesized, and characterized by 1H NMR, 13C NMR, Fourier transform infrared spectroscope（FTIR）, elemental analysis and X-ray photoelectron spectroscopy（XPS）. α-Diimine ligand 1b, bis[N,N′-（2,6- dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2b, {bis[N,N′-（2,6-dimethyl- phenyl）imino]-2,3-butanediylidene}dibromonickel were also synthesized and characterized for comparison. The pre-catalyst 2a with sterically bulky, electron-donating group tert-butyl, activated by diethylaluminum chloride （DEAC） and tested in the polymerization of ethylene, was very highly active[2.01×107 g PE/（mol Ni？h？0.1 MPa）] and led to a very highly branched polyethylene（ca. 35―103 branches/1000 C）. The state of the polyethylene obtained varied from plastic, elastomer polymers to the oil-like hyperbranched polymers.

Catalyst Enhanced Chemical Vapor Depositionof Nickel on Polymer Surface

Catalyst enhanced chemical vapor deposition of nickel film on high Tg polymers such as teflon(PTFE), polyimide(PI), and polysulfone(PS) was investigated by hot wall and cold wall CVD, in which Ni(dmg)_2, Ni(acac)_2, Ni(hfac)_2, Ni(TMHD)_2, and Ni(cp)_2 are used as precursors, and palladium complexes are used as catalysts. The films obtained were shiny with silvery color. The Ni was metallic and the purity of Ni was about 92%-95% from XPS analysis. SEM micrographs show that the film had good morphology. The conductivity of the film was about 0.5-4 W·cm^(-1). Ni films had good adhesion with polyimide and polysulfone.

Nickel(Ⅱ) Complex Bearing a Salicylaldimine Ligand：Synthesis,Crystal Structure and Application in Norbornene Polymerization

A novel salicylaldimine ligand and its mononuclear nickel complex [NiL]（L = 2-[[[2,6-bis（diphenylmethyl）-4-methylphenyl]imino]methyl]phenol） have been synthesized and characterized by IR spectrum, elemental analysis and thermogravimetry（TG）. The molecular structure of the complex has been measured by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/n with a = 13.281（3）, b = 16.938（3）, c = 13.981（3） ？, β = 97.03（3）o, V = 3121.2（11） A^3, C80H64N2O2Ni, Mr = 1144.04, Z = 2, Dc = 1.217 Mg/m^3, μ = 0.361 mm^-1, F（000） = 1204, the final R = 0.0582 and wR = 0.1108（I 〉 2s（I））. The compound showed excellent catalytic activity up to 12.78 × 10^6 g of PNB（polynorbornene）（mol of Ni）^-1 h^-1 for the addition polymerization of norbornene（NB） by using methylaluminoxane（MAO） as a cocatalyst.

Dimerization of Propylene by Nickel (Ⅱ) and Cobalt (Ⅱ) Catalysts Based on Bidentate Nitrogen-phosphino Chelating Ligands

The catalytic property of propylene dimerization by several nickel (Ⅱ), cobalt (Ⅱ) complexes containing N-P bidentate ligands was studied in combination with organoaluminum co-catalysts. The effects of the type of aluminum co-catalysts and its relative amount, the nature of precursors in terms of ligand backbone and metal center were investigated. The results indicated that precursor I (N,N-dimethyl-2-(diphenylphosphino)aniline nickel (Ⅱ) dichloride) exhibited high activity in propylene dimerization in the presence of the strong Lewis acid Et3Al2Cl3, whereas low productivity by its cobalt analogues was observed under identical reaction conditions.

Synthesis, Structure and Norbornene Polymerization Catalyzed by Bis{1-[[(3- ethyl-6-methyl-2-pyridinyl)imino]methyl- enyl]-2-naphthalenolato-N,O}nickel( Ⅱ)

The title complex bis{1-[[（3-ethyl-6-methyl-2-pyridinyl）imino]methylenyl]- 2-na- phthalenola-to-N,O}nickel has been synthesized by the reaction of 1-[[（3-ethyl-6-methyl-2- pyridinyl） imino] methylenyl]-2-naphthalenol with Ni（CH3 COO）2 ·4H2 O, and characterized by IR spectrum and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 11.100（2）, b = 15.900（3）, c = 18.000（4）, V = 3176.8（11）3, C38 H34 N4 NiO2, Mr = 637.40, Z = 4, Dc = 1.333 g/cm3, μ = 0.651 mm-1, F（000） = 1336, the final R = 0.0783 and wR = 0.2119. This title compound was investigated for the catalytic behavior towards norbornene（NB） vinyl addition polymerization. And the complex exhibited good catalytic activity to catalyze norbornene polymerization using MAO as a cocatalyst.

Synthesis,Structure and Norbornene Polymerization Catalyzed by Bis{(2-benzhydryl-4,6-dimethyl-phenyl)-(3,5-di-tert-butyl-2-methyl-benzylidene)-amine-N,O}nickel(Ⅱ)

The title complex bis{（2-benzhydryl-4,6-dimethyl-phenyl）-（3,5-di-tert-butyl-2-methyl-benzylidene）-amine-N,O}nickel has been synthesized by the reaction of（2-benzhydryl-4,6-dimethyl-phenyl）-（3,5-di-tert-butyl-2-methyl-benzylidene）-amine with Ni（CH3COO）2·4H2O, and characterized by IR spectrum and single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 12.373（4）, b = 18.434（7）, c = 27.814（10） A, β = 92.291（6）o, V = 6339（4） A^3, C7 2H8 0N2 Ni O2, Mr = 1064.09, Z = 4, Dc = 1.115 g/cm^3, μ = 0.350 mm^-1, F（000） = 2280, the final R = 0.0846 and wR = 0.2926（I 〉 2s（I））. This title compound was used as homogeneous catalysis of polymerization of norbornene, and the complex exhibited good catalytic activity to catalyze norbornene polymerization using MAO as a cocatalyst.

Synthesis, Structure and Catalytic Activity of a Palladium(Ⅱ) Complex Based on 4-Chloro-2-[(6-methyl-pyridin-2-ylimino)-methyl]-phenol Ligand

The title complex bis{4-chloro-2-[（6-methyl-pyridin-2-ylimino）-methyl]-phenol}-palladium（Ⅱ）（C_（26）H_（20）Cl_2N_4O_2Pd） has been synthesized by the reaction of 4-chloro-2-[（6-methylpyridin- 2-ylimino）-methyl]-phenol with Pd（CH_3COO）_2, and characterized by IR spectrum and elemental analysis. Single-crystal X-ray diffraction analysis results further confirmed the molecular structures. The crystal belongs to the monoclinic system, space group P2_1/c with a = 4.1324（2）, b = 23.5432（16）, c = 11.8943（8） A, β = 91.238（5）o, V = 1156.93（12） ？~3, C_（26）H_（20）Cl_2N_4O_2Pd, M_r = 597.76, Z = 2, D_c = 1.716 g/cm^3, μ = 1.067 mm^（-1）, F（000） = 600, the final R = 0.0247 and w R = 0.0677（I 〉 2σ（I））. In the presence of methylaluminoxane（MAO）, the complex exhibits excellent catalytic activities（1.737×10~7 g of PNB（mol of Pd）^（-1）·h^（-1）） in the vinyl polymerization of norbornene.

Supporting of Nickel(Ⅱ) Acenaphthenediimine with Free Amino Group for Ethylene Polymerization

Bis （4-（4-amino-3, 5-diethylbenzyl）-2, 6-diethylphenylimino） acenaphthene] di- chloronickel （NiLCl2） was prepared and supported on SiO2 modified by methyl trichlorsilane（S-1） and on SiO2-MgCl2/TiCl4 （S-2） respectively. Two supported catalysts S-1 and S-2 used as catalysts for ethylene polymerization were studied and the influences of various polymerization conditions, including the polymerization temperature, cocatalysts, Al/Ni molar ratio on the catalytic activity, branching degree and branch length of PE were also investigated. The experimental results show that the supported catalysts exhibit higher catalytic activity for ethylene polymerization, the highest catalytic activity of S-1 using AlEt2Cl as cocatalyst at 50 ℃, reaching 5.8×10^5gPE/molNi·h, and needed lower Al/Ni molar ratio compared to homogeneous analogue.

新型超支化镍系催化剂的合成及对乙烯齐聚的催化性能

以直链十二胺为核的0.5代超支化大分子(R12-0.5G)和丁二胺为原料,合成出一种新型的1.0代超支化大分子(R12-1.0G)。然后以R12-1.0G、水杨醛和Ni Cl2·6H_2O为原料,依次经过希夫碱反应和络合反应合成了一种新型的超支化水杨醛亚胺镍系催化剂。FTIR、1H NMR、UV和MS证实合成产物的结构与理论结构相符。在合成的基础上,并对该催化剂催化乙烯齐聚的性能进行了研究。考察了溶剂种类、反应温度、反应压力、Al/Ni比等条件对该催化剂催化乙烯齐聚性能的影响。结果表明,该催化剂具有良好催化乙烯齐聚的性能,当以甲苯为溶剂,在甲基铝氧烷(MAO)活化下,随着反应压力和Al/Ni比增加,催化活性增加;而催化活性随着反应温度的增加先升高后下降;在反应温度为25℃、反应压力为0.5MPa、Al/Ni比为1500时,该催化剂的活性可达5.03×105g/(mol Ni·h),聚合产物主要是C6以下的低碳烯烃,含量高达89%以上。相同条件下,其催化乙烯齐聚的活性低于与其具有类似结构的"扫帚型"镍系催化剂。

有机镍化合物催化烯烃聚合的研究进展

综述了有机镍化合物如烯丙基镍、乙酰丙酮镍、茂镍、二亚胺镍等催化烯烃聚合的研究进展。有机镍化合物可催化烯烃、α-烯烃(如乙烯、丙烯等)的齐聚及聚合、催化极性单体(如甲基丙烯酸甲酯、降冰片烯等)以及位阻较大的环烯烃、取代二烯烃、苯乙烯等的均聚和共聚。

用于乙烯聚合的镍配合物催化剂的研究进展

具有弱亲电性的Ni原子与含孤对电子(如O、N、P等)的化合物配位所得的Ni配合物可以用于催化乙烯聚合,因其良好的稳定性和极性功能基团容忍性的优点,成为乙烯聚合用后过渡金属催化剂研究的热点之一。Ni配合物催化乙烯聚合的研究不仅有利于探索乙烯聚合机理模型,而且对设计具有高选择性乙烯聚合Ni催化剂具有建设性意义。笔者从Ni配合物配体的位阻效应和电子效应对其催化乙烯聚合活性和聚合产物特性影响方面,综述了近5年Ni配合物在乙烯聚合方面的研究进展,详细阐述了Ni配合物中取代基的位阻效应和电子效应的影响规律,并展望了Ni配合物在乙烯聚合领域的发展前景。

共价负载型α-二亚胺镍催化剂的制备及其催化乙烯聚合

合成了一种含有胺基的α-二亚胺镍配合物,该配合物与三乙基铝改性的SiO2通过共价键结合形成负载型α-二亚胺镍催化剂,以一氯二乙基铝为助催化剂,研究了其对乙烯聚合性能的影响。实验结果表明,以庚烷作溶剂时,该催化剂具有较高的催化活性,聚合温度和n(Al):n(Ni)对催化活性和聚合物的性质有较大的影响。得到的聚乙烯产品是不仅含有甲基支链,而且含有乙基、丙基、丁基、戊基甚至长支链的高支化聚乙烯。支链数(1 000 C)随聚合温度升高而增加,从0℃时的12．94增加到75℃时的116．02,重均相对分子质量和熔融温度却随聚合温度的升高而下降。用扫描电镜表征聚合物的形态,结果发现催化剂的形态对聚合物形态具有模板作用。

SnO_2-SiO_2负载Cu、Ni催化剂的CO_2加氢反应性能

采用表面反应改性法制备了SnO2 SiO2 (SnSiO)表面复合物载体 ,用等体积浸渍法制备了SnSiO担载的Cu Ni双金属催化剂。借助BET、XRD、TPR、IR和微反等技术研究了SnSiO及其负载的Ni、Cu双金属催化剂的表面构造、化学吸附及CO2 加氢反应性能。结果表明 :SnSiO是SnO2 单分子层价联于SiO2 表面的复合氧化物 ,仍保持类似SiO2载体的孔结构和比表面 ;SnO2 引入SiO2 表面后可以有效地促进CuO、NiO的还原 ,还原后成为负载在SnSiO载体表面的Cu Ni合金 ;CO2 在负载型Cu Ni合金表面Cu或表面Ni位上发生化学吸附 ,形成线式和剪式吸附态 ;CO2 在催化剂上的加氢反应产物主要是CH3 OH、CH4 、CO和H2 O ,生成CH3 OH的选择性与催化剂组成及反应条件密切相关。Cu Ni催化剂 ,在 0 5MPa ,170℃ ,H2 /CO2 (mol/mol)为 3的条件下 ,CH3 OH的选择性达到 84 6 %。

CO_2和CH_3OH直接合成碳酸二甲酯用Cu-Ni/ZrO_2-SiO_2催化剂

采用表面反应改性法制备了ZrO2 SiO2 (ZrSiO)表面复合物 ,用等体积浸渍法制备了ZrSiO担载的Cu Ni双金属催化剂 ,并用IR ,TPD ,TPSR和微反技术考察了CO2 和CH3 OH在催化剂表面上的化学吸附及反应性能 .实验结果表明 :在Cu Ni/ZrSiO催化剂上存在着Cu Ni金属位M ,Lewis酸位Zrn + 和Lewis碱位Zr O-三类活性中心 ;CO2 在金属位和Lewis酸位的协同作用下可形成CO2 卧式吸附态 ,此吸附态在 142℃左右可解离成M CO和Zr O-;CH3 OH在Lewis酸位和Lewis碱位的协同作用下可形成解离吸附态Zr OCH3 和Zr OH ;CO2 和CH3 OH在Cu Ni/ZrSiO催化剂表面上的主要反应产物为碳酸二甲酯 (选择性在 85 %以上 ) ,另有少量的CH2 O ,CO和H2 O .

N-(2,6-二烷基苯基)-2-呋喃甲酰胺镍配合物的合成及其催化甲基丙烯酸甲酯的聚合

以呋喃甲酸、5-叔丁基-2-呋喃甲酸为起始物,在PCl3作用下,与苯胺、2,6-二烷基苯胺反应(烷基为乙基、异丙基),合成了4个N-(2,6二-烷基苯基)-5-叔丁基-2-呋喃甲酰胺有机配体,同时以N-(2,6-二乙基苯基)-5-叔丁基-2-呋喃甲酰胺与trans-[NiCl(Ph)(PPh3)2]反应合成了1个新的呋喃甲酰胺镍配合物,并采用核磁共振(1H-NMR)、红外光谱(IR)、质谱(MS)及元素分析(EA)对它们的结构进行了表征。以该配合物为催化剂,在甲基铝氧烷(MAO)作用下对甲基丙烯酸甲酯进行了催化聚合,以配合物中等的催化活性得到了富含间规结构的聚甲基丙烯酸甲酯(PMMA)。

含吸电子基团配体的α-二亚胺-Ni(Ⅱ)上乙烯聚合反应性能

合成了一种新型的含溴α-二亚胺配体及其Ni配合物,并采用核磁共振氢谱、核磁共振碳谱、元素分析、傅里叶变换红外光谱和X射线光电子能谱进行了表征.同时以二乙基氯化铝为助催化剂用于乙烯聚合反应,考察了温度、Al/Ni摩尔比和配体结构对聚合反应性能的影响.结果表明,在25oC,Al/Ni摩尔比为600时,该催化剂活性最高,可达3.73×107g/(mol·h·MPa),与不含吸电子基团Br的同类催化剂活性相当,且催化剂热稳定性和产物聚乙烯支化度明显提高.