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1.
在H_2O和乙醇形成的二元体系中,以CuCl_2·2H_2O为铜源,无水NaAc为沉淀剂,聚乙二醇(PEG)为形貌控制剂,采用一步水热法制备了氧化铜纳米材料。采用X射线衍射(XRD),扫描电子显微镜(SEM)和透射电子显微镜(TEM)等多种手段对产物进行结构表征。结果表明,所得产物具有单斜结构的氧化铜纳米片构建的球形花结构。研究了其生长过程,提出了相关的化学反应和可能的形成机制。  相似文献   

2.
在室温条件下,以甲醇和水为混合溶剂,由四溴代对苯二甲酸(H2TBTA)和硝酸铜分别与吡啶(py)和咪唑(im)构筑了2个一维(1D)铜配位聚合物:[Cu(TBTA)(py)3]n(1)和{[Cu(TBTA)(im)3]·(H2O)}n(2),对2个配合物进行了元素分析、红外分析、热重分析和X-射线单晶衍射等表征。在配合物1和2中,中心Cu(Ⅱ)离子都处于五配位环境;H2TBTA配体中羧基均采用单齿配位模式;配合物2存在π-π相互作用且氢键较1丰富。  相似文献   

3.
在室温条件下,以甲醇和水为混合溶剂,由四溴代对苯二甲酸(H2TBTA)和硝酸铜分别与吡啶(py)和咪唑(im)构筑了2个一维(1D)铜配位聚合物:[Cu(TBTA)(py)3]n(1)和{[Cu(TBTA)(im)3]·(H2O)}n(2),对2个配合物进行了元素分析、红外分析、热重分析和X-射线单晶衍射等表征。在配合物1和2中,中心Cu(Ⅱ)离子都处于五配位环境;H2TBTA配体中羧基均采用单齿配位模式;配合物2存在π-π相互作用且氢键较1丰富。  相似文献   

4.
用紫外差光谱、红外光谱法和荧光猝灭法研究了典型多环芳烃蒽与苯甲酸及其羟基取代衍生物邻羟基苯甲酸和对羟基苯甲酸之间的作用机理。实验结果表明,在此芳香羧酸与蒽之间存在定向的、特异性的作用,其作用方式受到反应物结构和环境酸度的影响。对苯甲酸和邻羟基苯甲酸而言,当pH<pKa时,二者之间以蒽离域大π电子与羧基质子之间的π-H氢键作用为主,pH>pKa时,π-π电子给体受体作用逐渐成为主要结合方式。邻位羟基的存在使得苯甲酸与蒽的作用强度明显降低。对羟基苯甲酸特殊的D-π-A型分子结构使得它在溶液中形成平面多分子聚集体,这种多分子聚集体的生成使得对羟基苯甲酸与蒽的结合方式不随酸度变化,在pH2.0~10.0的范围内均以π-π电子给体受体作用相结合,且结合强度大于苯甲酸和邻羟基苯甲酸。  相似文献   

5.
合成了一个单核镍配合物Ni(H2bpd)[NH(CH2COO)2](H2O)2(H2bpd=bis(2-pyridyl)methanediol,二(2-吡啶基)甲二醇),并用IR和X射线单晶衍射进行结构测定.该化合物属单斜晶系,P2(1)/c空间群,晶胞参数:a=1.031 05(3),b=1.003 52(3),c=1.747 270(10)nm,β=106.232(2)°,Z=4,Dc=1.638 g/cm3,μ=1.169 mm-1,F(000)=888,R=0.087 4,wR2=0.172 8.此化合物中金属镍原子与两个配体中的三个氮原子和三个氧原子螯合,形成扭曲的八面体构型.在氢键,π-π堆积和CH-π作用下,化合物形成了3D结构.  相似文献   

6.
A coordination polymer of [Zn(BBP)(p-CPOA)]n(where BBP is 2,6-bis(benzimidazolyl)pyridine and p-CPOA is p-carboxylato-phenoxyacetate dianion) has been synthesized and characterized by elemental analysis, IR, TG, and the single crystal structure was determined by X-ray diffraction. The crystal crystallizes in the monoclinic system, space group of P21/n with a=1.397 3(4) nm, b=1.138 4(3) nm, c=1.575 9(5) nm, β=91.805(1)°, V=2.505 4(13) nm3, Z=4, Dc=1.513 g·cm-3, μ=1.030 mm-1 and F(000)=1 168. Zn(Ⅱ) ion is penta-coordinated and surrounded by two carboxylate O atoms from two different p-CPOA groups in a bis-monodentate mode, three N atoms from the 2,6-bis(benzimidazolyl)pyridine ligand, completing a distorted trigonal bipyramidal coordination configuration. The structure is a helix with a long pitch of 1.138 4 nm. Under direction of supramolecular recognition and attraction, the adjacent chains are formed the double-stranded chain through π-π stacking between the 2,6-bis(benzimidazolyl)pyridine ligands and hydrogen-bonding interactions. A three-dimensional supramolecular network is further constructed through these interactions between the helices. The TG shows that its chain skeleton is thermally stable up to 382 ℃. CCDC: 626650.  相似文献   

7.
在没有外加掺杂剂的条件下,以FeCl3,Fe(NO3)3,Fe2(SO4)3,FePO4等多种铁盐为氧化剂,在水溶液中采用"无模板"的方法制备了具有较高电导率的聚苯胺纳米结构.铁盐是一种强酸弱碱盐,在水溶液中发生水解释放出质子,质子可以作为掺杂剂进入聚苯胺主链,因此,在苯胺的聚合过程中,铁盐同时起到氧化剂和掺杂剂的双重功能,进一步简化了导电聚苯胺纳米结构的合成条件,降低了反应成本.FTIR,UV-Vis,XRD等结构表征证实所得的纳米结构的聚苯胺均为掺杂态.试验发现,铁盐较低的氧化/还原电位使产物具有较小的直径和较高的电导率和结晶性.不同的对阴离子对聚苯胺产物的形貌有一定的影响,但对产物的结构和性能影响不大.铁盐与苯胺单体的比例对聚苯胺的形貌和电导率均有较大的影响.  相似文献   

8.
高恩君  刘蕾  朱明昌  吴琼 《中国化学》2009,27(7):1285-1290
本文报道了一个锌配合物[Zn(bipy)(pmal)(H2O)]·2H2O(其中bipy = 2,2’-联吡啶, pmal = 苯基丙二酸)的合成,晶体结构及其光谱学研究。并通过单晶X射线衍射,元素分析,红外光谱等手段对它进行了表征。同时,利用紫外光谱和荧光光谱方法考察了该配合物与小牛胸腺DNA的键和作用。琼脂糖凝胶电泳实验的结果说明该配合物的平面结构对pBR 322DNA切割作用显著。  相似文献   

9.
合成了新配合物[Cu(phen)2Cl]·ClO4·H2O(phen=o—phenanthroline),并用IR和X射线单晶衍射法对其结构进行了表征.晶体结构解析表明,标题配合物属单斜晶系,空间群为P2(1)/n,晶胞参数α=1.18086(8)nm,b=1.52855(10)nm,c=1.29572(9)nm,α=90°,β=93.1770(10)°,γ=90.000°,V=2.3352(3)nm^3,Z=4,Dc=1.641Mg/m^3,Mr=576.86,μ=1.210mm^-1,F(000)=1172,偏差因子R1=0.0481,ωR2=0.1424.在配合物[Cu(phen)2Cl]·ClO4·H2O中,Cu(Ⅱ)离子处于四个N原子和一个Cl^-离子构成的三角双锥几何构型中.分子间利用氢键作用,π-π堆积作用形成二维层状结构.层与层间通过弱氢键作用形成三维空间结构.  相似文献   

10.
合成了新配合物[Cu(phen)2Cl].ClO4.H2O(phen=o-phenanthroline),并用IR和X射线单晶衍射法对其结构进行了表征.晶体结构解析表明,标题配合物属单斜晶系,空间群为P2(1)/n,晶胞参数a=1.18086(8)nm,b=1.52855(10)nm,c=1.29572(9)nm,α=90°,β=93.1770(10)°,γ=90.000°,V=2.3352(3)nm3,Z=4,Dc=1.641Mg/m3,Mr=576.86,μ=1.210mm-1,F(000)=1172,偏差因子R1=0.0481,wR2=0.1424.在配合物[Cu(phen)2Cl]·ClO4.H2O中,Cu(Ⅱ)离子处于四个N原子和一个Cl-离子构成的三角双锥几何构型中.分子间利用氢键作用,π-π堆积作用形成二维层状结构.层与层间通过弱氢键作用形成三维空间结构.  相似文献   

11.
1-Picolyl-3-propylbenzimidazolium bromide (LBr) was prepared from benzimida- zole by alkylation with 2-chloromethyl-pyridine in the presence of NaH, followed by quaternization with 1-bromopropane. Ligand LBr was treated with AgBr in CH2Cl2 to afford a dinuclear silver(I) complex L2Ag2Br4 (1). In complex 1, a 2-D supramolecular layer is formed through two types of π-π stacking interactions. Fluorescent emission spectra of ligand LBr and complex 1 are described.  相似文献   

12.
纳米药物传输系统由于其独特的性质已经成为抗肿瘤新药的研究热点,本文首先对纳米药物传输系统进行简介,然后聚焦于通过药物-载体间π-π堆叠作用构建的抗肿瘤纳米药物传输系统,对高分子胶束、碳纳米材料(碳纳米管和石墨烯)以及可注射小分子(水)凝胶等三种基于药物-载体间π-π堆叠作用构建的抗肿瘤纳米药物传输系统的研究进展进行了介绍。  相似文献   

13.
本文采用一种简单、低耗的方法成功制备了氧化石墨烯(GNO)-自掺杂聚苯胺(SPAN)纳米复合材料,并通过扫描电子显微镜和差分脉冲伏安技术对该纳米复合材料的形貌及电化学性质进行了表征。GNO片层与交联的SPAN之间强烈的π-π*堆积作用和静电排斥作用,使复合材料形成一种独特的三维交联的纳米墙结构,这极大地提高了该复合材料的导电性、稳定性和电化学催化活性,可实现对氯霉素(CAP)的高灵敏检测。在0.1~100μmol/L的浓度范围,CAP的还原峰电流与其浓度具有良好的线性关系,检测限达到9.4×10-8 mol/L。此外,该方法具有优异的选择性和良好的回收率,可以用于实际样品中CAP的检测。  相似文献   

14.
合成了一系列含有1,5-二氧萘基仿生体系的线性供体和折叠体, 用稳态荧光光谱法定量研究了它们的临界簇集浓度(CAgC)及其影响因素. 结果显示, DX(1,4-二氧六环, Dioxane)-H2O和CH3CN-H2O二元溶剂中的簇集程度与Ф值(有机溶剂的体积分数)有关. 在DX-H2O和CH3CN-H2O体系中, 分子间与分子内π-π芳环堆积作用能促进簇集. 折叠体的分子内折叠加强了簇集程度. 线性供体的自卷曲程度随Ф值的增大而变小, 随分子中1,5-二氧萘基数目的增多而增大.  相似文献   

15.
合成了3种化合物 [2-ClPyH]2CoCl4(1), [2-ClPyH]2NiCl4(2)和[2-ClPyH]2CuCl4(3), 单晶X射线衍射法晶体结构测定结果表明, 这3种化合物是同形加合物, 在它们的结构中, [2-ClPyH]+离子呈平面状, 而[MCl4]2-离子为变形的四面体. 晶体结构分析发现晶体中存在N—H…Cl和C—H…Cl氢键, 以及Cl…Cl分子间相互作用和π-π堆积作用. 对自由状态下独立的配位离子进行的几何构型优化, 以及三维周期性条件下几何结构优化的量子化学计算结果表明, 标题化合物中具有方向性和选择性的氢键决定延伸性结构的方向, 而相对较弱的卤素…卤素作用在最终晶体结构的确定中扮演很重要的角色.  相似文献   

16.
The syntheses, physical characterization and crystal structures of two new molecular copper(II) complexes of composition [Cu(C5H5N)2(C7F5O2)2] (1) and [Cu(C5H5N)2(C7F5O2)2(H2O)] (2) (C5H5N = py = pyridine and C7F5O2 = pfb = pentafluorobenzoate) are reported. Single-crystal X-ray structure determinations revealed that in 1, the Cu2+ ion, which lies on a crystallographic inversion centre, is coordinated to two py molecules and two oxygen atoms from two monodentate pfb anions, resulting in a trans-CuN2O2 square planar geometry. In 2, the Cu2+ ion is also coordinated to two py and two pfb species in addition to a water molecule in the apical site of a distorted CuN2O3 square pyramid. In the crystal packing, both 1 and 2 show segregated aromatic π-π stacking interactions in which (py + py) and (pfb + pfb) ring-pairings are seen, but no (py + pfb) pairings occur. Crystal data: 1: C24H10CuF10N2O4, Mr = 643.88, space group , a = 8.0777 (3) Å, b = 8.0937 (3) Å, c = 10.5045 (5) Å, α = 90.916 (3)°, β = 93.189 (2)°, γ = 118.245 (3)°, V = 603.36 (4) Å3, Z = 1. 2: C24H12CuF10N2O5, Mr = 661.90, space group , a = 7.5913 (5) Å, b = 15.6517 (6) Å, c = 21.1820 (14) Å, α = 95.697 (4)°, β = 94.506 (2)°, γ = 91.492 (4)°, V = 2495.2 (3) Å3, Z = 4.  相似文献   

17.
A new ligand of N-benzyl-N'-(2-pyridyl)urea L and its self-assembly product with CuCl2, [Cu(Ⅱ)LCl2]∞ 1, have been synthesized and structurally characterized by IR, 1H NMR and single-crystal X-ray diffraction analysis. In the structure of L, the urea groups adopt Z,E conformation to form dimers through intermolecular hydrogen bonds; while in complex 1, it assumes Z,Z conformation to fit for the coordination sphere of the Cu(Ⅱ) ions. The coordinated units are connected through intermolecular N-H...Cl hydrogen bonds to form an extended 2D framework. Finally, a 3D structure is obtained via π-π stacking interactions between pyridyl rings  相似文献   

18.
Dented nanospheres show promising potential in drug delivery,nanomotors,etc.However,it is still challenging to prepare them by homopolymer self-assembly because of the strict structural requirements of the homopolymer.Herein,we propose a strategy for preparing dented nanospheres from homopolymers by co-assembly with a short peptide.They were co-assembled from poly(2-hydroxy-3-((4-(ethoxycarbonyl)phenyl)amino)propyl methacrylate) (PHBzoMA59) and (S)-2-((S)-2-((((gH-fluoren-9-yl)methoxy)carbonyl)amino)-3-phenylpro-panamido)-3-phenylpropanoic acid (Fmoc-FF-OH).PHBzoMA homopolymers can only self-assemble into nanospheres without dent,and the addition of a short peptide introduced hydrogen bonding and complementary π-π stacking interactions led to the final dented nanosphere morphology.The weight fractions of the short peptide can be adjusted to regulate the final morphology.It was confirmed that the radius of curvature of the dent on the surface was related to the organic bubble inside the protospheres prepared at critical aggregation concentration(CAC).The organic bubble can be adjusted by altering the kind of organic solvent and solution pH,which allowed control over the dented nanosphere dimension.The use of different organic solvents with various polarities allows adjustment of the interfacial tension,and hence the denting degree.This degree can also be controlled by manipulating the solution pH to (de)protonate the short peptide and homopolymer.Furthermore,the versatility of this method was highlighted by using a different homopolymer and the applicability of the resulting dented nanospheres was demonstrated by decoration with gold nanoparticles.Overall,this study provided important insights and a new simple strategy to prepare dented nanospheres in a controlled fashion.  相似文献   

19.
We have investigated the ability of para-X-phenylboronic acid (para-X-ba) to enable reactivity of trans-1,2-bis(4-pyridyl)ethylene (bpe) to direct intermolecular [2 + 2] photodimerization via computational chemistry. Para-X-ba would support the formation of discrete four component hydrogen bonded molecular assemblies wherein π-π stacking of a pyridyl-functionalized alkene would conform to undergo [2 + 2] photodimerization.We have demonstrated by computational 1H NMR data the effect of electron-withdrawing and donating substituents in (para-X-ba):::(bpe)||(bpe):::(para-X-ba) complexes to assemble bpe into π-π stacking via –(B)O − H···N– hydrogen bonds to react to afford (para-X-ba):::tpcb:::(para-X-ba) complexes (X = NO2, CN, F, Cl, Br, C(O)CH3, OCH3, OH, NH2 and H where || and ∙∙∙ denote π-π stacking and hydrogen bonds).Also, these interactions have been investigated at M05-2X/6-311++G** level of theory in detail in terms of the energetic, geometrical parameters and electron density properties to characterize and to examine the strengthening of the interactions. There are good relationships between the NMR, AIM, energy data and Hammett constants.  相似文献   

20.
The complex [Tm(TBTA)1.5(bipy)(H2O)2]n (H2TBTA = 2,3,5,6-tetrabromoterephthalic acid, bipy = 2,2-bipyridyl) has been synthesized in water-methanol solution at ambient temperature and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum and thermogravimetric analysis. The crystal belongs to triclinic, space group P1 with a = 11.1429(2), b = 11.485(2), c = 12.872(2), V = 1498.1(5)3 , Z = 2, C22H14Br6N2O9Tm, Mr = 1098.74, Dc = 2.436 g/cm3 , μ(MoKα) = 11.013 mm-1 , F(000) = 1022, T = 296.15 K, the final R (I >2σ(I)) = 0.0494 and wR (all data) = 0.1246. The asymmetric unit of the complex is composed of one Tm ion, one and a half of coordinated TBTA 2-anions, one bipy, two coordinated and one lattice water molecules. The adjacent metal ions are bridged by TBTA 2- anions to form a 2D wave-like layer.  相似文献   

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