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1 INTRODUCTION There has been great and considerable interest in the study of copper nitrite complexes because they are relevant to the study of copper-containing enzymes involved in the denitrification process[1]; in particular, copper-nitrite complexes are potentially relevant to the nitrite reductases[2] (the enzyme from Achromobacter Cycloclastes) which convert NO2- to NO and/or N2O. Many attempts have been made to synthesize a variety of copper-nitrite complexes, in which the n…  相似文献   

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Synthesis and Structure of [Cu(OH)2(H2O)2(4—C5H4N—COOH)2]   总被引:1,自引:0,他引:1  
钟兆思  孙道峰 《结构化学》2001,20(6):478-480
1 INTRODUCTION Supramolecular chemistry and crystal engineering of coordination compounds have attracted considerable interests nowadays owing to the fascinating structural diversity and potential applications as functional materials[1,2]. Generally, architectures of supramolecules are formed through hydrogen bonds, ?- ?stacking interaction or other weak interactions between the molecules. Recently, many supramolecular compounds containing silver(I) and copper(II) species have been re-…  相似文献   

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1 INTRODUCTION The picolinic acid (picH), also called pyridine- 2-carboxylic acid, has a broad spectrum of physio- logical effects on the activity functions of both ani- mal and plant organisms. It is attributed increasing interest due to its ability to …  相似文献   

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二[4,4,4—三氟—1—(2—噻吩基)丁二酮—1,3]合铜...   总被引:2,自引:0,他引:2  
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1 INTRODUCTION Polythiotungstate complexes can be prepared from the protonation of one sulfur atom of [WS4]2- and subsequent intramolecular redox reactions[1,2]. For example, [(S)2W(m-S)2W(m-S)2W(S)2]2 was formed by the acidification of a diluted aqueous solution of (NH4)2[WS4] with dilute H2SO4[3]. When a diluted aqueous solution containing [WS4]2 was acidified with 0.1mol/L HCl, [(S)2W(m-S)2(O)- W(H2O)(m-S)2W(S)2]2 was formed[4]. [(S)2W- (m-S)2(S)W(m-S)2W(S)2]2 was form…  相似文献   

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螺嗪类化合物是在螺吡喃基础上发展起来的一类新的光致变色化合物 ,与螺吡喃相比 ,具有化学性质稳定 ,光响应快 ,抗疲劳性好等优点 ,在光信息记录、非银感成像、非线性光电器件、光过滤器、防伪以及装饰等领域具有很大的应用潜力[1] 。吲哚啉螺嗪的基本结构及光致色变过程可表示为 :  其中X为 (杂 )芳环与苯环相并 ,可带有取代基。螺嗪SP(Spirooxazine)经光λ1激发后 ,开环变成具有大共轭体系的开环体PMC(Photomerocya nies) ,从而使其光吸收红移 ,停止激发后 ,PMC可通过λ2 或以热作用方式回…  相似文献   

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通过E-[4-[2-(4-羟基苯基)乙烯基]吡啶与1,n-二溴烷烃亲核取代反应合成了4,4‘-[1,n-亚烷基双[(E)-2-(4-氧基苯)乙烯基]]双吡啶[n=2(Ia),3(Ib),4(Ic),6(Id)]。用元素分析、红外、紫外和质子核磁共振谱鉴定了Ia-Id的结构。将Ia-Id的稀溶液用中压汞灯和低压汞灯交替照射,发现其分子内光环加成反应的存在,并且随着亚烷基碳链的延长,反应速度加快。研究还发现锌离子可以与吡啶环上氮原子发生螯合作用使分子内光环加成反应加快。本文化合物荧光很弱,在较高浓度下有较强分子间激基缔合物荧光。  相似文献   

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李宝龙  徐艳  刘琦  王化勤  徐正 《中国化学》2002,20(2):187-190
IntroductionCrystalengineeringofsupramoleculararchitecturessustainedbycoordinatecovalentbondsorhydrogenbondsrepresentsarapidlyexpandingfieldthatofferspo tentialfordevelopmentofnewclassesoffunctionalsolids .1,2 Thearchitecturesofcoordinationpolymerscanbe…  相似文献   

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A novel La( III )‐Cu( II ) heterometallic coordination polymer {[LaCu2(NTA)2(4,4′‐bpy)(H2O)3]NO3·5H2O]n, where H3NTA denotes nitrilotriacetic acid and 4,4′‐bpy denotes 4, 4‐bipyridine, was synthesized and characterized by IR spectrum, elemental analysis and X‐ray diffraction. The complex crystallizes in the triclinic space group Pi with cell parameters a = 1.33710(10) nm, b = 1,44530(10) nm, c =1.0949(2) nm, α = 71.905(7)°, β = 74.327(7)°, γ = 64.427(9)°, V = 1.7912(4) nm3and Z = 2. It consists of heterometallic units, in which each La( II ) ion is coordinated in a distorted monocapped square antiprism by three oxygen atoms from water molecules and six carboxyl oxygen atoms from five NTA3? ions, and each Cu( I ) ion is coordinated by one nitrogen atom from 4,4′‐bpy and one nitrogen atom, three oxygen atoms from NTA3?. In the title complex, La( I ) ions and Cu( II ) ions are connected by the heterometallic bridging of NTA3?, constructing a two‐dimensional network structure along the [110]. And it is extended into an infinite three‐dimensional network structure by the formation of homometallic bridging of Cu‐4, 4′‐bpy‐Cu, exhibiting a certain inclusion ability.  相似文献   

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In the polymeric title compound, [CuI(C10H8N4)]n, the CuI atom is in a four‐coordinated tetrahedral geometry, formed by two I atoms and two pyridine N atoms from two different 4,4′‐(diazenediyl)dipyridine (4,4′‐azpy) ligands. Two μ2‐I atoms link two CuI atoms to form a planar rhomboid [Cu2I2] cluster located on an inversion centre, where the distance between two CuI atoms is 2.7781 (15) Å and the Cu—I bond lengths are 2.6290 (13) and 2.7495 (15) Å. The bridging 4,4′‐azpy ligands connect the [Cu2I2] clusters into a two‐dimensional (2‐D) double‐layered grid‐like network [parallel to the (10) plane], with a (4,4)‐connected topology. Two 2‐D grid‐like networks interweave each other by long 4,4′‐azpy bridging ligands to form a dense 2‐D double‐layered network. To the best of our knowledge, this interwoven 2‐D→2‐D network is observed for the first time in [Cu2I2]–organic compounds.  相似文献   

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A novel aromatic diamine monomer, 3,3′‐diisopropyl‐4,4′‐diaminodiphenyl‐3′′,4′′‐difluorophenylmethane (PAFM), was successfully synthesized by coupling of 2‐isopropylaniline and 3,4‐difluorobenzaldehyde. The aromatic diamine was adopted to synthesize a series of fluorinated polyimides by polycondensation with various dianhydrides: pyromellitic dianhydride (PMDA), 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA), 4,4′‐oxydiphthalic anhydride (ODPA) and 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA) via the conventional one‐step method. These polyimides presented excellent solubility in common organic solvents, such as N,N‐dimethylformamide (DMF), N,N‐dimethyl acetamide (DMAc), dimethyl sulfoxide (DMSO), N‐methyl‐2‐pyrrolidone (NMP), chloroform (CHCl3), tetrahydrofuran (THF) and so on. The glass transition temperatures (Tg) of fluorinated polyimides were in the range of 260–306°C and the temperature at 10% weight loss in the range of 474–502°C. Their films showed the cut‐off wavelengths of 330–361 nm and higher than 80% transparency in a wavelength range of 385–463 nm. Moreover, polymer films exhibited low dielectric properties in the range of 2.76–2.96 at 1 MHz, as well as prominent mechanical properties with tensile strengths of 66.7–97.4 MPa, a tensile modulus of 1.7–2.1 GPa and elongation at break of 7.2%–12.9%. The polymer films also showed outstanding hydrophobicity with the contact angle in the range of 91.2°–97.9°.  相似文献   

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A green and convenient approach to the synthesis of novel 4,7‐diaryl‐2‐oxo(thio)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐5‐one derivatives from appropriate aromatic aldehydes and 5‐aryl‐1,3‐cyclohexanedione with urea or thiourea in the presence of dilute HCl as catalyst in water is described. This method provides several advantages such as environmental friendliness, low cost, high yields, and simple workup procedure. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H NMR. The crystal and molecular structure of 4‐(4′‐chlorophenyl)‐7‐(4′‐methoxyphenyl)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2,5‐dione 5m have been determined by single crystal X‐ray diffraction analysis. The crystal of compound 5m belongs to monoclinic with space group P‐21/c, a = 1.4353 (4) nm, b = 1.4011 (4) nm, c = 0.9248 (3) nm, α = 90.00°, β = 101.242 (6)°, γ = 90.00°, Z = 4, V = 1.8241 (9) nm3, R1 = 0.0448, and wR2 = 0.1022. J. Heterocyclic Chem., (2011).  相似文献   

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The ternary Cu(II) complex with 2,2′‐bipyridyl (bipy) and L‐methioninate (L‐Met) has been synthesized and characterized by elemental analysis, molar conductivity, UV‐Vis spectra, IR spectra and pH‐potentiometric titration methods. The structure of the complex [Cu(L‐Met) (bipy) (H2O)]ClO4 · 3/8H2O was characterized by the X‐ray diffraction analysis. It crystallizes in the triclinic system, space group P1 with four molecules in a unit cell of dimensions, a = 0.7656(2) nm, b = 1.3142(3) nm, c = 2.0596(4) nm, α = 97.70(3)°, β = 97.96(3)°, γ = 94.33(3)°, V= 2.0244(8) nm3, R1, = 0.0441 and wR2 = 0.0678. The crystal contains four crystllographically independent [Cu(L‐Met) (bipy) (H2O)]+ complexes (Cu1—Cu4), having a distorted square‐pyramidal geometry with the same coordinated atoms around each copper center. The base plane is occupied by two nitrogen atoms of one bipy, the amino nitrogen atom and one carboxylate oxygen atom from each independent L‐Met moiety, and one water oxygen at an axial position. Cu1 and Cu3 are essentially enantiomers of Cu2 and Cu4. The four molecules are packed with each other by intermolecular hydrogen‐bonding and aromatic‐ring stacking interactions.  相似文献   

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A novel cadmium(II) coordination polymer, poly[[[bis­(4,4′‐bipyridine)cadmium(II)]‐μ3‐4,4′‐dicarboxy­biphenyl‐3,3′‐di­carboxyl­ato] 0.35‐hydrate], {[Cd(C16H8O8)(C10H8N2)2]·0.35H2O}n, was obtained by reaction of Cd(CH3COO)2·3H2O, 4,4′‐bipyridine (4,4′‐bpy) and biphenyl‐3,3′,4,4′‐tetra­car­boxylic acid (H4L) under hydro­thermal conditions. Each CdII atom lies at the centre of a distorted octa­hedron, coordinated by four O atoms from three H2L2− ligands and N atoms from two monodentate 4,4′‐bpy ligands. Each H2L2− ligand coordinates to three CdII atoms through two carboxyl­ate groups, one acting as a bridging bidentate ligand and the other in a chelating bidentate fashion. Two Cd atoms, two H2L2− anions and four 4,4′‐bpy ligands form a ring dimer node, which links into an extended broad zonal one‐dimensional chain along the c axis.  相似文献   

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Reactions of CuSCN with tetramethylthiuram disulfide in CH3CN in the presence of styrene and N,N,N′,N″,N″‐pentamethyldiethylenetriamine gave rise to a new copper(I) complex ofN,N′‐dimethyldithiocabamate ([CU(S2CNMe2)]2)n. The title compound crystallized in the triclinic P‐1 space group with lattice parameters a=0.7610(4) nm, b=0.8911(4) nm, c=0.9268(5) nm, α=68.66(1)°, β=83.88(2)°, γ=79.31(2)°, V=0.5748(5) nm3, Z=2. The compound has a unique 1D chain structure composed of CuSCSCuSCS eight‐membered rings and a pair of CU? S bonds, the structure of which has been determined by singlecrystal X‐ray crystallography. The isolation of this compound may provide some helpful information for the cause of the induction periods of the reverse atom transfer radical polymerization.  相似文献   

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本文合成了一种新型配位聚合物[Cu(pa)(vim)2]n(pa为邻苯二甲酸阴离子,vim为1-乙烯基-1H-咪唑),并用x射线单晶衍射仪和元素分析表征了其单晶结构。晶体属单斜晶系,C2/c空间群,晶胞参数分别为:a=1.6527(3) nm, b=0.81800(16) nm, c=1.4463(3) nm, β=113.19(3)°, V=1.7973(7) nm3, Z=4, Dc=1.537 g?cm-3。 [I>2σ(I)]时:R1=0.0476, wR2=0.1235,对所有数据:R1=0.0693, wR2=0.1355。配合物的结构中存在沿着c轴的zigzag聚合链。每个铜原子位于晶体中心,与两个N原子和两个O原子进行配位,形成了扭曲的平面结构。电化学研究表明在配合物中Cu2+/Cu+的氧化还原是一个单电子的准可逆过程。  相似文献   

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Homobinuclear complex (HCuL)2 (1) (H3L: N-3-carboxylsalicylidene-N'-salicylaldehyde-1,2-diaminoethane) was obtained from self-organization of the reported complex HCuL, and its crystal structure was determined through X-ray diffraction at room temperature. The crystal of complex 1 belongs to monolinic system, the space group Cc, a=2.5326(5) nm, b=0.88861(18) nm, c=1.3738(3) nm, β=96.95(3)°, Z=4, R1=0.0520, wR2=0.1185. (HCuL)2 is a dimeric molecule and has extended phenolic oxygen-bridged structure. In addition, using mononuclear complex HCuL as building blocks, Cu(Ⅱ)-Mg(Ⅱ)-Cu(Ⅱ) heterotrinuclear complex 2 was synthesized, and its crystal structure also has been determined by X-ray analysis. The crystal of complex 2 is of monoclinic system, space group Pc, a=1.1816(2) nm, b=1.5599(3) nm, c=1.9642 (4) nm, β=98.22°, Z=2, R1=0.0701, wR2=0.1498. Each dissymmetricai cell unit of complex 2 contains two heterotrinucler neutral molecules: {[CuL(H2O)]Mg[CuL(CH3OH)]} and {[CuL]Mg[CuL(H2O)]}.  相似文献   

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