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1.
The tetramer of octaethylporphyrin nickel complex [OEP(Ni)], connected with diacetylene and ethylene linkages, was synthesized. Its structural and electronic properties were studied, proving that two constituents of the diacetylene-group connected OEP(Ni) dimer face to each other in s-cis conformation about the ethylene linkage but not so closely as to induce a transannular π-electronic interaction between them.  相似文献   

2.
1 INTRODUCTION Transition metal complexes with ferrocene are of considerable interest in the past fifty years because of their novel structures and special properties[1, 2]. The chemistry of ferrocene and its derivatives has become richer and richer in the last decade. Many complexes containing ferrocenyl have been synthesized and characterized[3~5]. Recently we have reported the synthesis and crystal structure of dibromo[1,1?bis(diphenylphosphino)- ferrocene]cadmium (Ⅱ)[6]. Herein we…  相似文献   

3.
The solid-state structure of Mo(CO)2(DMMA)2(PDA) (DMMA = dimethyl maleate, PDA = o-phenylenediamine) was determined by X-ray diffraction of single crystal. The complex crystallizes in the hexagonal space group P6122 with a = 11.085(5), b = 11.085(5), c = 33.653(21) Å, γ = 120°, and Z = 6. The geometry of this bis(DMMA) complex is distorted octahedral with the two CO groups cis to each other and trans to the PDA ligand and the two DMMA ligands trans to each other and cis to the two CO ligands. The orientations of the two trans DMMA ligands are mutually perpendicular and each DMMA ligand eclipses an N-Mo-CO vector. The carbon-carbon double bond of DMMA is bonded to molybdenum unsymmetrically with the olefin carbon adjacent to a coordinated amino group closer to the metal than that adjacent to a carbonyl group. The conformation of each DMMA is that the two ester groups attached to DMMA lie in the regions described by N-Mo-C and N-Mo-N. Bond-distance calculations indicate that each keto oxygen of the ester groups in the region described by N-Mo-C forms a hydrogen bond with an amino hydrogen on the PDA ligand; this hydrogen bonding is responsible for the observed conformation of the complex. The conformalion of this complex in the solid-state is in agreement with the results in solution predicted according to 1H NMR spectral data.  相似文献   

4.
Single crystal X-ray diffraction analyses of two nitromethane complexes of furanotribenzo-21-crown-7 (1 and2) and the nitromethane complex of dibenzo-2l-crown-7 (3) are reported. The two nitromethane complexes1 and2 are polymorphic in that the macrocyclic ring adopts the dentist's chair conformation in both structures, with a single nitromethane molecule coordinating to either the lower, concave (1) or upper, convex (2) face of the crown ether. Complex3 adopts an entirely different conformation with a coplanar arrangement of the crown ether oxygen atoms binding a single nitromethane molecule. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. 82209 (31 pages).The U.S. Government right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged.  相似文献   

5.
The analysis of structural parameters of azobenzene- and stilbene-bridged calix[4]arene obtained from AM1 calculation are in good agreement with those obtained from X-ray crystallography. The bridge longer than 9.0 Å such as p,p-trans-azobenzene and p,p-trans-stilbene cannot be constructed over the narrow rim of calix[4]arene through two ethylene oxide linkers. The m,m-stilbene bridge is the most promising photo switch because its shorter cis stereoisomer (5.85 Å) allows calix[4]arene to assume the perfect cone conformation, whilst its longer trans stereoisomer (8.00 Å) forces calix[4]arene to adapt a pinched cone conformation. The pinched cone conformation has longer distances between the neighbouring phenoxyl groups causing the weaker intramolecular hydrogen bonding and the upfield shifts of the phenolic proton signals to below 7.00 ppm. This upfield shift is useful for quick identification of pinched cone conformation of new calix[4]arene compounds.  相似文献   

6.
A new flexible ligand, 1,5-bis(8-oxaquinoline)-3-methylpentane (C5MeOQ), was synthesized and used in the preparation of the new dinuclear copper(II) complex 1: [Cu2(μ-OMe)2(μ-C5MeOQ)(NO3)2]. Single crystal X-ray analysis revealed that complex 1 contains dinuclear Cu(II) units with bridging methoxo groups. The ligand, C5MeOQ, takes on a bent conformation in order to connect to and complete the square planar coordination environment of both copper centers; and one of the two Cu(II) centers adopts a distorted square planar configuration as a result of the ligand conformation. The magnetic properties of complex 1 were investigated by variable-temperature magnetic susceptibility measurements in the 100–300 K range. Interestingly, the susceptibility data for complex 1 reveals that the compound is diamagnetic, suggesting the presence of very strong antiferromagnetic coupling interactions between the adjacent Cu(II) centers.  相似文献   

7.
A new metal containing molecular receptor was prepared from a 15-membered nickel(II) macrocyclic cyclidene platform and two cyclic tetramine (cyclen) recognition cites. In the saddle shaped conformation of the platform, the cyclen receptors are positioned for ditopic binding of difunctional substrates. NMR titration experiments demostrate that the molecule binds dicarboxylic acids in DMSO with apparent equilibrium constants ranging from 10 to 104 M-1. Incusion of dicarboxylates into the protonated macrocyclic host is shape-selective, with cis-1,2-dicarboxylates (succinate, maleate, and o-phthalate) being the best guests.  相似文献   

8.
田真宁  许旋 《物理化学学报》2008,24(8):1482-1486
对PPh2py配合物[M(CO)3(PPh2py)2](M=Fe, Ru)的三种构型的异构体1-6进行了研究. 其中PPh2py以两个P原子与M配位形成HH构型1(Fe)和4(Ru), 以一个P和一个N原子与M配位形成HT构型2(Fe)和5(Ru), 以两个N原子与M配位形成HH’构型3(Fe)和6(Ru). 结果表明, (1) PPh2py中P原子对HOMO轨道的贡献最大, PPh2py作为电子给体时易以P原子与金属原子结合. (2)从分子能量和相互作用能数据表明, 配合物中HH构型最稳定, HH'构型最不稳定, 这与合成产物为HH构型的结果一致. (3) 键长和Wiberg键级均表明P—M键比N—M键结合力强. P、M原子间存在σ键, 而N、Fe原子间仅存在nN→n*M或nN→σ*M-P的电荷转移作用. (4) HH构型中M对HOMO的贡献最大, PPh2py向M的电荷转移最强, 使M的负电荷最大, 故HH构型最易作为电子给体以M原子与第二个金属配位形成双核配合物.  相似文献   

9.
Iterative extended Hückel self-consistent charge calculations were performed for a number of conformations of Fe(II) porphin, a pyridine complex of Fe(II) porphin, and a pyridine-Fe(II)-porphin CO complex. For Fe(II) porphin, spin zero and spin 2 states were found to have their energy minimum in a planar conformation. Addition of the pyridine ligand results in an out-of-plane minimum energy conformation in the spin 2 case. Ligand bond formation is readily interpreted in terms of conventional chemical bonding theory. An energy-bond length curve was obtained for CO binding to pyridine-Fe(II)-porphin and found to be qualitatively reasonable.  相似文献   

10.
The interaction between polyacrylic acid and two water‐soluble cellulose ethers (methylcellulose and hydroxyethylcellulose) was studied. Viscometry, velocity sedimentation, small‐angle neutron scattering, and potentiometric titration methods show the formation of stable water‐soluble interpolymer complexes due to hydrogen bonding between nondissociated groups of polyacrylic acid and proton‐acceptor groups of the cellulose ether. Both complexes exhibit polyelectrolyte properties and keep the conformation of the semirigid chain component. The hydrophobic groups in the methylcellulose macromolecule are responsible for the absence of complexes at temperatures greater than 60 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1323–1330, 2000  相似文献   

11.
谢学群  杨春龙  李前进 《结构化学》2007,26(9):1009-1012
The title compound [Mn(DPMT)2Cl2(H2O)2] (DPMT = 1-[[2-(2,4-dichlorophenyl)- 1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole) was synthesized by the reaction of MnCl2·4H2O and DPMT in ethanol solution and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 23.913(4), b = 7.8883(13), c = 8.6291(14) , β = 95.816(3)o, V = 1619.4(5) 3, Z = 2, C24H26Cl6MnN6O6, Mr = 762.15, Dc = 1.563 g/cm3, μ = 0.950 mm-1, S = 1.045, F(000) = 774, R = 0.0462 and wR = 0.0981. The molecular structure is a centrosymmetric conformation, and two ligands are symmetrically located on both sides of the Mn atom. The manganese atom is surrounded by two nitrogen atoms from ligands, two chlorine atoms and two oxygen atoms from water molecules to form a slightly distorted octahedral geometry.  相似文献   

12.
In this study, a new twisting gold(I) isocyanide complex based on tetraphenylethene (TPE), TPE-NC-Au, was designed and synthesized. It exhibits aggregation induced phosphorescence (AIP) characteristics, owing to the incorporation of Au moiety and conformation rigidification in the aggregated states. Moreover, the emission color of the crystalline solid of TPE-NC-Au changes from blue (454 nm) to green (500 nm) in response to mechanical grinding, due to the combined effects of conformation planarization, enhanced π…π stacking, as well as the emergence of aurophilic interactions in the ground amorphous state. Notably, the emission color can be restored upon solvent fuming, associating with the reconstruction of crystalline lattices. The AIP and switchable mechanochromism of TPE-NC-Au make it suitable for potential applications in bioimaging, sensing, and optoelectronic devices.  相似文献   

13.
CrystalStructureofCalix[4](dioxo)crown-6Acetonitrile(1:3)InclusionComplexZHONGZhen-Lin;CHENYuan-Yin;LUXue-Ran(DepartmentofChe...  相似文献   

14.
The direct preparation of the sodium complex of 5,11,17,23-tetra(tert-butyl)-25,27-di(ethoxymethoxy)-26,28-(diethylacetamido) calix[4]arene 1.NaI is reported. The crystal structure of 1.NaI shows the calix unit to be in a cone conformation with the sodium located in the cavity delineated by the oxygen atoms.  相似文献   

15.
王瑾玲  丁峰  郁铭 《有机化学》2004,24(11):1423-1428
利用1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮(PMBP)和对氨基苯乙酮(PAAP)制备了PMBP缩对氨基苯乙酮(PMBP缩PAAP)及其铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)和锌(Ⅱ)配合物,根据元素分析、红外、紫外、MS和1H NMR谱表征了结构.利用量子化学和分子力学计算方法对缩合反应的机理进行了探讨,较好地解释了PMBP-PAAP配体的烯胺酮式构型及其配合物的亚胺烯醇式构型.测定了化合物对大肠杆菌和金黄色葡萄球菌的抑制活性,其中以钴(Ⅱ)和铜配合物(Ⅱ)的抑菌活性最佳.  相似文献   

16.
以1,3-二(4-吡啶基)-丙烷(bpp)和邻苯二甲酸(1,2-H2bdc)为配体,通过水热法合成了过渡金属配合物M2(1,2-bdc)2(bpp)2·2H2O[M=Co(1),Ni(2)]和Cd(1,2-bdc)(bpp)·H2O(3).配合物1和2属单斜晶系P21空间群,具有相似的三维骨架结构.配合物中存在2种配位环境相似的金属中心,每个金属中心采取六配位的畸变八面体构型,与来自2个1,2-bdc配体的3个氧原子和2个bpp配体的2个氮原子以及1个水分子配位.1,2-bdc配体采取单齿/双齿螯合的配位模式将金属离子连接成M1-(1,2-bdc)-M2右手螺旋链.bpp配体采取Trans-Gauche(TG)构型,连接相邻的金属离子形成M1-(bpp)-M1链和M2-(bpp)-M2链.这3种链交织在一起构筑成具有{65.8}拓扑的三维结构.配合物3属单斜晶系P21/c空间群,具有单节点的双层二维结构.Cd(Ⅱ)离子采取七配位的畸变五角双锥体构型,与来自2个1,2-bdc配体的4个氧原子,2个bpp配体的2个氮原子和1个水分子配位.1,2-bdc配体采取双齿螯合/双齿螯合的配位模式将Cd(Ⅱ)离子连接成Cd-(1,2-bdc)-Cd链.bpp配体采取TG构型,连接相邻的Cd(Ⅱ)离子,形成Cd-(bpp)-Cd链.这2种链通过共享Cd(Ⅱ)离子交错排列构筑成二维结构.配合物3显示出强的荧光,最大发射位于408 nm处,对应于配体的π*-π跃迁.不同有机小分子对配合物3的荧光强度有不同程度的影响,苯胺对其有显著的猝灭作用,基于荧光猝灭机理,配合物3可用于选择性检测苯胺分子.  相似文献   

17.
The reaction of with p-CH3C6H4S(O)2O(CH2)3C6H5 produces (η5-C5H5)(OC)3Mo(CH2)3C6H5. This is only the second structurally characterized organometallic species in which an aromatic moiety is separated by three or more methylene groups. The alkyl chain adopts a staggered conformation, the Mo-C(1)-C(2)-C(3)-C(4) unit is nearly coplanar, and the alkyl chain eclipses the trans-carbonyl group on Mo. NMR evidence indicates that this conformation is preserved in solution.  相似文献   

18.
SynthesisandCrystalStructureof[Lu(NO_3)_3(H_2O)_2(CH_3CN)](Benzo-15-C-5)·CH_3CNWangRui-Yao;JinZhong-Sheng;NiJia-Zuan(Laboratoryo...  相似文献   

19.
合成了铜(II)与羟基丁二酸和2,2'-联吡啶形成的配位聚合物{[Cu(malate)(2,2'-bipy)]•3H2O} (其中malate=羟基丁二酸根, 2,2'-bipy=2,2'-联吡啶), 通过X射线衍射测定了单晶结构, 并进行了元素分析、红外光谱、紫外光谱、热分析等研究. 配合物属单斜晶系, 空间群P2(1)/c; 晶胞参数: a=0.70132(10) nm, b=1.9730(3) nm, c=1.18998(16) nm, β=94.551(3)°; Z=2; 最终偏离因子R=0.0483. 配合物中每个铜(II)原子与来自2,2'-联吡啶的两个氮原子和两个羟基丁二酸根的三个氧原子配位, 形成畸变的三角双锥结构单元. 每个羟基丁二酸根以R构型方式桥联两个三角双锥结构单元, 沿a轴方向无限延伸形成一维链. 两条平行链以面对面的方式重叠, 彼此吡啶环之间存在强的(-(相互作用, 加之C吡啶环—H…O羧基弱相互作用形成新颖的梯状双链结构, 比邻的梯状双链又通过分子间O羟基-H…O羧基氢键沿a轴方向共同构筑了具有隧道的三维结构.  相似文献   

20.
The crystal and molecular structure of BFL-TCNQ has been determined by single-crystal X-ray diffraction analysis. The complex crystallizes in the monoclinic space group C2/c, a=17.915(3), b=12.238(3), c=13.531(3) Å, β = 115.16(1)°, and Z=4. The complex has a mixed-stacked crystal structure in which BFL molecules exist in a twisted conformation and TCNQ molecules are dimensionally similar to uncomplexed TCNQ. The complex is diamagnetic and is an insulator with a room-temperature conductivity less than 10−9 s cm−1. The FT-IR spectrum of the BFL-TCNQ complex reveals that the degree of charge transfer between the two component molecules is essentially null.  相似文献   

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