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1.
One of the products of the reaction of the activated cluster Os3(CO)11(NCMe) with As(p-tol)3 in refluxing nonane has been shown by spectroscopic and X-ray crystallographic methods to be Os3(CO)93-AsC6H4CH3)(μ3-C6H3CH3), which contains a benzyne moiety bonded asymmetrically from one carbon to one osmium via a σ bond and from a second carbon to form a bridge between the remaining two osmium atoms.  相似文献   

2.
用X-射线衍射法测定了[C5H4C(CH3)(C3H7)CH2CH= CH2]NdMg2(μ3-OH)(μ3-Cl)(μ2-Cl)3(THF)4Cl的晶体结构。它属三斜晶系,空间群为P1- ,a= 12.698(3), b= 13.616(3), c= 13.712(3), α= 68.91(3), β= 84.34(3), γ= 63.07(3)°, V= 1966(1)3, Mr= 849.74, Dx= 1.412 g·cm - 3, μ= 1.7297 m m - 1, F(000)= 840, Z= 2, R= 0.073, w R= 0.086(I≥3σ(I))。分子中Nd(Ⅲ)原子的配位数为八,形成一个严重扭曲的八面体结构。两个Mg 原子的配位情况相似,它们的配位数都是六,构成两个扭曲的八面体。这三个八面体通过三个共用平面联接  相似文献   

3.
The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-ray diffraction. The crystal is rhombohedral, space group R3 with a=1.947 0(3) nm, b=1.947 0(3) nm, c=1.768 3(3) nm, α=90°, β=90°, γ=120°, V=5.805(2) nm3, Z=3, the final R value is 0.051 2. The complex contains a novel tetranuclear cation with four Er3+ ions connected by four μ3-OH ions and six bridging carboxyl groups. Each erbium ion is coordinated by three μ3-OH, three carboxylic oxygen atoms from three L-proline, and two or one oxygen atoms from water molecules.  相似文献   

4.
本文研究了1-苯基-3-甲基-4-苯甲酰基吡唑啉酮-5(PMBP)与二苯基亚砜(DPSO)的甲苯溶液在高氯酸介质中对铒(Ⅲ)的协同萃取,测得了萃合物的组成和各萃取反应的平衡常数及热力学函数增量.  相似文献   

5.
The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-ray diffraction. The crystal crystallizes in a triclinic system, space group P1 with a=1.306 3(2) nm, b=1.319 4(4) nm, c=1.950 2(4) nm, α=90.597(14)°, β=93.998(11)°, γ=94.093(13)°, V=3.344 1(12) nm3, Z=2, the final R indices are R1=0.065 4, wR2=0.126 2 respectively. The complex contains a novel tetranuclear cluster cation with four Er3+ ions connected by four μ3-OH ions and six bridging carboxyl groups. Each erbium ion is coordinated by three μ3-OH, three carboxylic oxygen atoms from three α-alanine and two oxygen atoms from water molecules, forming a square-antiprismatic coordination polyhedron.  相似文献   

6.
以茚基锂与6, 6-二甲基富瓦烯的环外双键加成反应合成了一个新型取代茂基锂 [(C9H7)Me2C]C5H4Li (1, 其中C5H4代表一取代环戊二烯基), (1)与无水三氯化钐按2∶1摩尔比反应后, 再用与稀土钐的摩尔比为3∶1的钠砂处理, 合成了二价钐的三核双金属配合物[(NaC9H6)Me2CC5H4]2Sm(Ⅱ)(THF)2 (2, 其中C9H6代表茚基). 该配合物经元素分析和红外光谱表征, 并发现 (2) 能高活性地催化甲基丙烯酸甲酯聚合, 得到等规含量较高的聚甲基丙烯酸甲酯.  相似文献   

7.
Abstract

The synthesis of novel bis(N-aryl-imino-phosphoranyl)methanes of the type CH2(PR2?N-Ar)2 has been accomplished by reaction of methylene-bisphosphines with arylazides. These compounds have been fully characterized by 1H, 31P and 13C NMR, IR spectroscopy, Field Desorption Mass Spectroscopy (? FDMS) and elemental analysis. Variable temperature NMR experiments and single crystal X-ray structure determinations of CH2(PPh2?N-C6H4-CH3-4)2 (la) and CH2(PMe2?N-C6H4-NO2-4)2 (1f) reveal that bis(N-aryl-imino-phosphorany1)methane occurs as tautomer 1. Crystals of la are orthorhombic, space group Pcab, with a = 26.602(2), b = 20.521(1), c = 11.8859(7) Å and V = 6488.5(7) Å3 (2 = 8, R = 0.045 and Rw = 0.066). The crystals of lf are monoclinic, space group C/2c, with a = 20.153(4), b = 5.952(1), c = 16.930(5) Å, β = 106.24(3)° and V = 1949.6(6) Å3 (Z = 4, molecular symmetry C2, Rw = 0.051 and R, = 0.079). Both molecules consist of 2 iminophosphoranyl units bridged by a methylene group. The P?N bond distances of 1.568(2) and 1.566(2) Å for la and 1.580(4) Å for lf represent normal values for iminophosphoranyl compounds. The N-C bond lengths of 1.386(2) and 1.390(2) A (la) or 1.372(5) A for If indicate that some electron delocalisation over the N-aryl moiety takes place. In la the electron delocalisation takes place separately in each iminophosphoranyl entity, while in lf electron delocalisation occurs only in the N-aryl-NO2 moiety.

Compound la is easily deprotonated using lithium-diisopropylamide or NaH and shows typical iminophosphoranyl chemistry, since with CO2 an aza-Wittig reaction has been found and with HX (X?CI, Br) protonation of both imide nitrogen atoms has been observed.  相似文献   

8.
《Solid State Sciences》2001,3(7):783-788
The synthesis and structural characterization of the complex [Ru(η6-C6H6)(η6-C6H4(CH3)COOCH3)] [BF4]2 (2) and of its precursor [Ru(η6-C6H4(CH3)COOCH3)Cl2]2 (1) are reported. Compound (2) has been characterized in two polymorphic modifications (2a and 2b) and the molecular organization in the solid state has been investigated. The complex [Ru(η5-C5H5)(η6-C6H5OH)][PF6] (3) has also been investigated; it has been shown to possess a disorder similar to that observed in the high temperature phase of related systems such as [Ru(η5-C5H5)(η6-C6H6)][PF6].  相似文献   

9.
The synthesis of 1,5-bis(2-dihydroxyphosphoryl-4-ethylphenoxy)-3-oxapentane [(HO)2(O)P(C6H3CH2CH3)(OCH2CH2)2O(C6H3CH2CH3)P(O)(OH)2] (H4K2) and single crystal X-ray diffraction study of H4K2 · 2H2O (I) are described. The crystals are orthorhombic, a = 33.291(4) Å, b = 8.9374(10) Å, c = 8.1021(9) Å, V = 2410.6(5) Å3, Z = 4, space group Cmc21, R = 0.0484 for 2566 reflections with I > 2σ(I). In I, the molecules of H4K2 are hydrogen-bonded to two crystallographically independent H2O molecules to give neutral conglomerates H4K2 · 2H2O. The electroanalytical characteristics of poly(vinyl chloride) membranes based on H4K2 were tested. Cu2+ and Zn2+ complexes with H4K2 and Er3+, Nd3+, and complexes with H4K2, 1,5-bis[2-(dihydroxyphosphoryl-4-methoxy)phenoxy]-3-oxapentane, 1,5-bis[2-(dihydroxyphosphinyl)phenoxy]-3-oxapentane, and 1,8-bis[2-(dihydroxyphosphinyl)phenoxy]-3,6-dioxaoctane were prepared.  相似文献   

10.
采用自洽场分子轨道UHF/6-31G**从头算法,研究了1,2-C4H6→2-C4H6异构化反应机理,优化了基态势能面上反应物、过渡态、中间体和产物的几何构型,并对各驻点能量进行了零点能校准.结果表明该反应经历一个1-甲基环丙烯生成产物比经两步氢迁移反应历程更易发生.  相似文献   

11.
两种镍的配合物[Ni(NH2CH2CH2CH2NH2)3]Cl2 (1)和[Ni(C6H4N2H4)2Cl2] (2)已经被合成并且通过红外和单晶X射线衍射分析对其进行了表征。在配合物1中,镍原子处于手性假八面体[NiN6]的几何构型中,它与三个1,3-丙二胺分子形成了三个六元环。在配合物2中,镍原子除了与两个o-苯二胺分子通过四个Ni-N键形成两个五元环外,它还与两个Cl原子配位形成了反式Ni-Cl2,这不同于以往报道过的镍的二胺配合物。这两个镍的配合物被MAO, MMAO或Et2AlCl活化后,对乙烯的二聚合或三聚合显示了很好的催化活性[对于配合物2,催化活性达到3.59×106 g mol-1 (Ni) h-1]。  相似文献   

12.
13.
14.
冯作锋  黄吉玲  钱延龙  孙俊全  陈伟 《中国化学》2002,20(11):1401-1405
IntroductionItiswellknownthatmetallocenesactivatedwithmethylaluminoxane (MAO)arehighlyactivehomogeneousZiegler Nattacatalyststhatproducepolyolefinwithcon trolledstereoregularityandnarrowmolecularweightdistri bution ,1 4 however,themolecularweightofthepolym…  相似文献   

15.
合成和表征了2个锆的配合物:Bis[N-(3-tert-butylsalicylidene) allylaminato] zirconium dichloride (4)和Bis[N-(3-tert-butylsali-cylidene)-iso-butylaminato] zirconium dichloride (5),并且得到了配合物4的单晶结构。在引发剂的作用下,配合物4和苯乙烯进行自由基共聚,得到高分子化催化剂6。在助催化剂MMAO的存在下,4,56都可以催化乙烯聚合。最高活性为3.7×106 g PE·(mol Zr)-1·h-1。  相似文献   

16.
在惰性气氛下, 用2 mol甲基锂处理二(1,2-二苯基-4-甲基环戊二烯基)二氯化锆, 合成了大立体位阻的二甲基二茂锆化合物[(1,2-Ph2-4-MeCp)2ZrMe2]. 经元素分析、 核磁共振氢谱、 碳谱和X射线晶体衍射分析, 确定了该化合物的结构. 经Al( i Bu)3/Ph3C+B(C6F5)-4活化, 该化合物催化乙烯聚合反应显示出较高的催化活性, 生成高分子量及高熔点聚乙烯. 该体系的特点是在较低的n(Al)/n(Zr)比下即可有效地催化乙烯聚合.  相似文献   

17.
A series of novel α‐diamine nickel complexes, (ArNH‐C(Me)‐(Me)C‐NHAr)NiBr2, 1 : Ar=2,6‐diisopropylphenyl, 2 : Ar=2,6‐dimethylphenyl, 3 : Ar=phenyl), have been synthesized and characterized. X‐ray crystallographic analysis showed that the coordination geometry of the α‐diamine nickel complexes is markedly different from conventional α‐diimine nickel complexes, and that the chelate ring (N‐C‐C‐N‐Ni) of the α‐diamine nickel complex is significantly distorted. The α‐diamine nickel catalysts also display different steric effects on ethylene polymerization in comparison to the α‐diimine nickel catalyst. Increasing the steric hindrance of the α‐diamine ligand by substitution of the o‐methyl groups with o‐isopropyl groups leads to decreased polymerization activity and molecular weight; however, catalyst thermal stability is significantly enhanced. Living polymerizations of ethylene can be successfully achieved using 1 /Et2AlCl at 35 °C or 2 /Et2AlCl at 0 °C. The bulky α‐diamine nickel catalyst 1 with isopropyl substituents can additionally be used to control the branching topology of the obtained polyethylene at the same level of branching density by tuning the reaction temperature and ethylene pressure.  相似文献   

18.
Novel Ni(Ⅱ)-based acetyliminopyridine complexes 1b, 2b, 3b (1-3b), which are synthesized from ligands 1a, 2a, 3a (1-3a) and [NiCl2(DME)], are suitable precursors for the catalysts that are necessary for ethylene oligomerization and polymerization reactions, activated by methylaluminoxane (MAO).The MAO-treated 1-3b presents an active catalytic center, which may oligomerize and polymerize ethylene to produce linear α-olefins and polyethylene, respectively. The molecular weight distributions of oligomers that are obtained are in good agreement with the Schulz-Flory rules for oligomers>C4. The activity of oligomers show significant reliance on the structures of catalyst precursors.  相似文献   

19.
20.
合成并表征了含RCOO-基团的单核(Ni1~Ni2)及双核(Ni3)镍配合物[(2,6-R2-C6H3)—N=C(H)—(3-Ph-5-PhCOO-2-O-C6H2)-κ2-N,O]Ni(CH3)(pyridine)](R=iPr;3,5-tBu2C6H3),并用于催化乙烯均聚和共聚反应。 作为单组分催化剂,这些配合物可以有效地催化乙烯聚合得到中等相对分子质量的支化聚乙烯(PE)。 供电性的PhCOO—基团促进了催化剂Ni1的引发,从而在低温下比Ni0活性更高。 引入大位阻的2,6-(3,5-二叔丁基苯基)苯胺基团,催化剂Ni2在5×105 Pa下的活性高达1.8×106 g PE mol-1·Ni-1·h-1,是活性最高的水杨醛亚胺中性镍催化剂之一。 与相应的单核催化剂相比,双核催化剂Ni3对三苯基膦具有更好的耐受性。 这些催化剂可催化乙烯与1,5-己二烯、1,7-辛二烯、6-溴-1-己烯或10-十一烯酸甲酯的共聚合,制备功能化聚乙烯。  相似文献   

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