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1.
Three sandwich-type (phthalocyaninato)(porphyrinato) europium triple-decker complexes, namely Eu(2)(Pc)(2)(TClPP) (1), Eu(2)[Pc(β-OC(4)H(9))(8)](2)(TClPP) (2), and Eu(2)[Pc(β-OC(8)H(17))(8)](2)(TClPP) (3), have been designed, synthesized, and fabricated into nanotubes using nanoporous anodized aluminium oxide (AAO) membrane as the template. In particular, the effects of peripheral-substituents at the two phthalocyanine ligands in the triple-decker molecule on the molecular stacking relative to the alumina surface and the molecular packing mode in the nanotubes were clarified on the basis of the scanning electron microscopy (SEM), spectroscopic, and X-ray diffraction results. High-resolution TEM (HRTEM) images, in combination with the electronic absorption and XRD results, indicate that the discotic molecules of 1 without peripheral substituent on the phthalocyanine ligands form columnar structures on the alumina surface with homeotropic molecular stacking depending on the intermolecular π-π interactions in a head-to-tail manner. In good contrast, introduction of eight long octyloxy substituents at the peripheral-positions of the phthalocyanine ligands of 3 induces an increase in the interaction of the triple-decker molecules with the alumina surface, resulting in the formation of nanotubes with discotic molecules of 3 parallel stacking relative to the alumina surface depending on the intermolecular π-π interactions in a face-to-face manner. Most interestingly, introduction of eight shorter length butyloxy substituents at the peripheral-positions of the phthalocyanine ligands of 2 leads to the formation of nanotubes with discotic molecules of 2 parallel stacking relative to the alumina surface but depending on the intermolecular π-π interactions in a head-to-tail manner. X-Ray diffraction (XRD) data confirm the above-mentioned results.  相似文献   

2.
An asymmetrical perylene diimide 3, N-(4-methoxyphenyl)-N'-(4-nitrophenyl)-perylene-3,4,9,10-tetracarboxylic diimide, was synthesized, and its self-assembly and dissociation behaviors in chloroform was studied in detail by UV-vis and fluorescence spectroscopies. The resulting unique helical nanostructures from 3 were proposed to be self-assembled via the cooperative actions of π-π stacking, steric hindrance and electrophile-nucleophile type pairing.  相似文献   

3.
MoO(3) nanostructures with different morphologies, such as helical nanosheets, crosslike nanoflowers, and nanobelts, have been synthesized on a large scale by an environmentally friendly chemical route. The evolution process from helical nanosheets to crosslike nanoflowers to nanobelts is observed for the first time. The influences of reaction time and the molar ratio of molybdenum and H(2)O(2) on the morphologies of MoO(3) nanostructures have been investigated. The synthetic process is environmentally friendly and may be extended to synthesize nanostructures of other metal (W, Ti, and Cr) oxides.  相似文献   

4.
A series of five novel sandwich-type mixed (phthalocyaninato)(porphyrinato) europium triple-decker complexes with different numbers of hydroxyl groups at the meso-substituted phenyl groups of porphyrin ligand 1-5 have been designed, synthesized, and characterized. Their self-assembly properties, in particular the effects of the number and positions of hydroxyl groups on the morphology of self-assembled nanostructures of these triple-decker complexes, have been comparatively and systematically studied. Competition and cooperation between the intermolecular pi-pi interaction and hydrogen bonding in the direction perpendicular to the pi-pi interaction direction for different compounds were revealed to result in nanostructures with a different morphology from nanoleafs for 1, nanoribbons for 2, nanosheets for 3, and curved nanosheets for 4 and to spherical shapes for 5. The IR and X-ray diffraction (XRD) results reveal that, in the nanostructures of triple-decker 2 as well as 3-5, a dimeric supramolecular structure was formed through an intermolecular hydrogen bond between two triple-decker molecules, which as the building block self-assembles into the target nanostructures. Electronic absorption spectroscopic results on the self-assembled nanostructures reveal the H-aggregate nature in the nanoleafs and nanoribbons formed from triple-deckers 1 and 2 due to the dominant pi-pi intermolecular interaction between triple-decker molecules, but the J-aggregate nature in the curved nanosheets and spherical shapes of 4 and 5 depending on the dominant hydrogen bonding interaction in cooperation with pi-pi interaction among the triple-decker molecules. Electronic absorption and XRD investigation clearly reveal the decrease in the pi-pi interaction and increase in the hydrogen bonding interaction among triple-decker molecules in the nanostructures along with the increase of hydroxyl number in the order of 1-5. The present result appears to represent the first effort toward realization of controlling and tuning the morphology of self-assembled nanostructures of sandwich tetrapyrrole rare earth complexes through molecular design and synthesis.  相似文献   

5.
The synthesis of two high nuclearity lanthanoid clusters demonstrates the versatility of the carbonate anion as a robust cluster forming agent, potentially allowing for the formation of otherwise inaccessible core topologies. The complexes, [Gd(14)(CO(3))(13)(ccnm)(9)(OH)(H(2)O)(6)(phen)(13)(NO(3))](CO(3))(2.5)·(phen)(0.5) () and [Dy(14)(CO(3))(13)(ccnm)(10)(OH)(H(2)O)(6)(phen)(13)](CO(3))(2.5)·(phen)(0.5) () (ccnm = carbamoylcyanonitrosomethanide, phen = 1,10-phenanthroline), contain a [Ln(14)(CO(3))(13)(OH)] core in which the carbonate anions display four unique coordination modes. The complexes are chiral, and the ccnm ligands also display four unique coordination modes. Extensive intra- and intermolecular π-π stacking between phen ligands leads to the formation of 1D chains in the crystal structure. Both complexes display magnetic properties that are indicative of antiferromagnetic coupling, with complex displaying behaviour consistent with possible single molecule magnet properties.  相似文献   

6.
Three 1,8,15,22-tetrasubstituted phthalocyaninato nickel complexes Ni[Pc(alpha-OR)(4)] [H(2)Pc(alpha-OC(5)H(11))(4) = 1,8,15,22-tetrakis(3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(7)H(15))(4) = 1,8,15,22-tetrakis(2,4-dimethyl-3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(10)H(7))(4) = 1,8,15,22-tetrakis(2-naphthyloxy)phthalocyanine] (1-3) have been prepared by treating the corresponding metal-free phthalocyanines H(2)Pc(alpha-OR)(4) with Ni(acac)(2)2H(2)O in refluxing n-pentanol. Structures of the Langmuir monolayers of these compounds at different temperature have been investigated. Compound 1 formed nano-ring structures with the outer diameter of 70-150 nm and inner diameter of 50 nm at 25.0 degrees C while 2 and 3 formed round particles. This difference can be ascribed to the different substituents at alpha position. The morphologies of the aggregates of 1 in monolayers have been found to change with temperature. Decreasing in temperature induced the formation of regular quadrate crystals. UV-vis absorption spectra revealed strong intermolecular interactions in the nano-ring aggregates. Polarized UV-vis absorption spectra suggest a titled orientation with respect to the surface of substrate for phthalocyanine macrocycles in the nano-ring aggregates.  相似文献   

7.
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   

8.
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   

9.
An innovative strategy for circularly polarized luminescence (CPL) of carbon dots (CDs) has been developed: The achiral CDs displayed contrary supramolecular chirality and opposite CPL in two different bi-solvent systems, which are due to the formation of self-assembled helical nanostructures with two diverse assembly modes (P and M) in aggregate state via intermolecular π-π interactions and differential hydrogen bonding (H-bonding) without the need of any additional element of chirality.  相似文献   

10.
在微波辐射条件下合成了两种新的离子液体金属配合物[Ni(m-HNDA)2(H2O)4](1),[Zn(m-HNDA)2(H2O)4]·H2O(2),用元素分析、红外光谱、紫外光谱对它们进行了表征,通过X射线单晶衍射测定了它们的晶体结构.在晶体结构中,标题物通过基团间的嵌合作用,π-π相互作用和分子间氢键自组装成了三维网状的多孔结构.由氢键和π-π相互作用的强弱推测标题物的稳定性次序2>1,与实测热稳定性次序完全吻合;电化学性质表明,金属的配位改变了配体的循环伏安性质.另外,两种配合物可在水溶液中高选择性的识别氟离子.  相似文献   

11.
合成了新的离子液体金属配合物[Pb(m-HNA)(H2O)].NO3.3H2O(m-HNA为N,N′-二-羧甲基-2-丙基苯并咪唑盐),并通过元素分析,红外光谱,对其进行了表征,通过X射线单晶衍射测定了其晶体结构,在晶体结构中,标题物通过π-π相互作用、分子间氢键和配位键自组装成了三维网状结构。另外,电化学性质表明,该配合物的电解过程为准可逆过程。  相似文献   

12.
Design and synthesis of three novel [2 + 2] self-assembled molecular rectangles 1-3via coordination driven self-assembly of predesigned Pd(ii) ligands is reported. 1,8-Diethynylanthracene was assembled with trans-Pd(PEt(3))(2)Cl(2) in the presence of CuCl catalyst to yield a neutral rectangle 1via Pd-C bond formation. Complex 1 represents the first example of a neutral molecular rectangle obtained via C-Pd coordination driven self-assembly. A new Pd(2)(II) organometallic building block with 180° bite-angle 1,4-bis[trans-(ethynyl)Pd(PEt(3))(2)(NO(3))]benzene (M(2)) containing ethynyl functionality was synthesized in reasonable yield by employing Sonagashira coupling reaction. Self-assembly of M(2) with two organic clip-type donors (L(2)-L(3)) afforded [2 + 2] self-assembled molecular rectangles 2 and 3, respectively [L(2) = 1,8-bis(4-pyridylethynyl)anthracene; L(3) = 1,3-bis(3-pyridyl)isophthalamide]. The macrocycles 1-3 were fully characterized by multinuclear NMR and ESI-MS spectroscopic techniques, and in case of 1 the structure was unambiguously determined by single crystal X-ray diffraction analysis. Incorporation of Pd-ethynyl bonds helped to make the assemblies π-electron rich and fluorescent in nature. Complexes 1-2 showed quenching of fluorescence intensity in solution in presence of nitroaromatics, which are the chemical signatures of many commercially available explosives.  相似文献   

13.
Bian Y  Li L  Dou J  Cheng DY  Li R  Ma C  Ng DK  Kobayashi N  Jiang J 《Inorganic chemistry》2004,43(23):7539-7544
Three (1,8,15,22-tetrasubstituted phthalocyaninato)lead complexes Pb[Pc(alpha-OR)(4)] [H(2)Pc(alpha-OC(5)H(11))(4) = 1,8,15,22-tetrakis(3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(7)H(15))(4) = 1,8,15,22-tetrakis(2,4-dimethyl-3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(10)H(7))(4) = 1,8,15,22-tetrakis(2-naphthyloxy)phthalocyanine] (1-3) have been prepared as racemic mixtures by treating the corresponding metal-free phthalocyanines H(2)Pc(alpha-OR)(4) (4-6) with Pb(OAc)(2).3H(2)O in refluxing n-pentanol. The molecular structure of Pb[Pc(alpha-OC(5)H(11))(4)] (1) in the solid state has been determined by single-crystal X-ray diffraction analysis. This compound, having a nonplanar structure, crystallizes in the monoclinic system with a P2(1)/c space group. Each unit cell contains two pairs of enantiomeric molecules, which are linked by weak coordination of the Pb atom of one molecule with an aza nitrogen atom and its neighboring oxygen atom from the alkoxy substituent of another molecule, forming a pseudo-double-decker supramolecular structure in the crystals with a short ring-to-ring separation, 2.726 A, and thus a strong ring-ring pi-pi interaction. The decreased molecular symmetry for these complexes has also been revealed by the NMR spectra of 1 and 2. The methyl protons of the 3-pentyloxy and 2,4-dimethyl-3-pentyloxy side chains of 1 and 2, respectively, are chemically inequivalent. In addition to the elemental analysis and various spectroscopic characterizations, these compounds have also been electrochemically studied. Two one-electron oxidations and up to five one-electron reductions have been revealed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods.  相似文献   

14.
Li J  Wang S  Li S  Wang Q  Qian Y  Li X  Liu M  Li Y  Yang G 《Inorganic chemistry》2008,47(4):1255-1257
A water-chemical route to synthesize copper phthalocyanine (CuPC) is reported in this paper. The molecules were self-assembled into regular beta-CuPC single-crystal nanobelts simultaneously. The molecular structure of CuPC in the nanobelts was characterized by UV-vis absorption spectroscopy, MALDI-TOF-MS, and elemental analysis. The morphology and crystal phase of the nanobelts were investigated by electron microscopy and X-ray diffraction, respectively. Crucial factors for the formation of CuPC nanobelts were also investigated. The cooperative effect of the surfactant and copper powder was important for the formation of CuPC. The CuPC nanobelts were obtained through a self-assembly process. In addition, a phase transition process, which resulted in the formation of beta-CuPC single-crystal nanobelts, took place with prolonged time.  相似文献   

15.
A mononuclear Cobalt(Ⅱ) complex [CoL(H2O)2]n (H2L: 4,4′,6,6′-Tetrabromo-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol), has been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction single crystal structure analysis. The crystal of the complex belongs to monoclinic space group P21/c with a=2.516 8(3) nm, b=1.023 43(18) nm, c=0.789 17(14) nm, β=91.375(2)°, V=2.032 1(5) nm3, Z=4, Dc=2.317 Mg·m-3, μ(Mo Kα)=8.747 mm-1, F(000)=1 356, R1=0.049 7, wR2=0.110 4. The crystal structure of [CoL(H2O)2]n indicates that the complex consists of one cobalt(Ⅱ) atom, one L2- unit and two coordinated water molecules, and the coordination number of the cobalt(Ⅱ) atom is six. One-dimensional chain supramolecular structure is formed by intermolecular hydrogen bonds and π-π stacking of neighboring benzene rings. CCDC: 652649.  相似文献   

16.
To investigate the effects of metal–ligand coordination on the molecular structure, internal structure, dimensions, and morphology of self‐assembled nanostructures, two nonperipherally octa(alkoxyl)‐substituted phthalocyanine compounds with good crystallinity, namely, metal‐free 1,4,8,11,15,18,22,25‐octa(butyloxy)phthalocyanine H2Pc(α‐OC4H9)8 ( 1 ) and its lead complex Pb[Pc(α‐OC4H9)8] ( 2 ), were synthesized. Single‐crystal X‐ray diffraction analysis revealed the distorted molecular structure of metal‐free phthalocyanine with a saddle conformation. In the crystal of 2 , two monomeric molecules are linked by coordination of the Pb atom of one molecule with an aza‐nitrogen atom and its two neighboring oxygen atoms from the butyloxy substituents of another molecule, thereby forming a Pb‐connected pseudo‐double‐decker supramolecular structure with a domed conformation for the phthalocyanine ligand. The self‐assembling properties of 1 and 2 in the absence and presence of sodium ions were comparatively investigated by scanning electronic microscopy (SEM), spectroscopy, and X‐ray diffraction techniques. Intermolecular π–π interactions between metal‐free phthalocyanine molecules led to the formation of nanoribbons several micrometers in length and with an average width of approximately 100 nm, whereas the phthalocyaninato lead complex self‐assembles into nanostructures also with the ribbon morphology and micrometer length but with a different average width of approximately 150 nm depending on the π–π interactions between neighboring Pb‐connected pseudo‐double‐decker building blocks. This revealed the effect of the molecular structure (conformation) associated with metal–ligand (Pb? Nisoindole, Pb? Naza, and Pb? Obutyloxy) coordination on the dimensions of the nanostructures. In the presence of Na+, additional metal–ligand (Na? Naza and Na? Obutyloxy) coordination bonds formed between sodium atoms and aza‐nitrogen atoms and the neighboring butyloxy oxygen atoms of two metal‐free phthalocyanine molecules cooperate with the intrinsic intermolecular π–π interactions, thereby resulting in an Na‐connected pseudo‐double‐decker building block with a twisted structure for the phthalocyanine ligand, which self‐assembles into twisted nanoribbons with an average width of approximately 50 nm depending on the intertetrapyrrole π–π interaction. This is evidenced by the X‐ray diffraction analysis results for the resulting aggregates. Twisted nanoribbons with an average width of approximately 100 nm were also formed from the lead coordination compound 2 in the presence of Na+ with a Pb‐connected pseudo‐double‐decker as the building block due to the formation of metal–ligand (Na? Naza and Na? Obutyloxy) coordination bonds between additionally introduced sodium ions and two phthalocyanine ligands of neighboring pseudo‐double‐decker building blocks.  相似文献   

17.
本文合成了1个新的一维链状锰的配位聚合物{[Mn(HL)(phen)(H2O)2].1.5H2O}n,(H3L=2-羟基-5-羧基苯磺酸),并且进行了元素分析、红外、热重、荧光、紫外、粉末XRD及单晶X射线衍射等表征及研究。标题化合物属于单斜晶系,C2/c空间群,a=0.840 57(17)nm,b=1.757 5(4)nm,c=2.873 4(6)nm,β=92.54(3)°,V=4.240 7(16)nm 3,Z=4,R=0.027 0。每个Mn(Ⅱ)离子与邻菲咯啉配体的2个N原子、磺酸配体中的1个磺酸基O原子和羧基O原子以及2个配位水分子配位,展示出扭曲的八面体几何构型。2个相邻的Mn(Ⅱ)八面体单元通过1个磺酸基氧原子和1个羧基氧原子连接形成一维链状结构,该一维链进一步通过氢键作用构筑成三维网状结构。  相似文献   

18.
The reactions of bifunctional carboxylate ligands (1,8-naphthalimido)propanoate, (L(C2)(-)), (1,8-naphthalimido)ethanoate, (L(C1)(-)), and (1,8-naphthalimido)benzoate, (L(C4)(-)) with Cu(2)(O(2)CCH(3))(4)(H(2)O)(2) in methanol or ethanol at room temperature lead to the formation of novel dimeric [Cu(2)(L(C2))(4)(MeOH)(2)] (1), [Cu(2)(L(C1))(4)(MeOH)(2)]·2(CH(2)Cl(2)) (2), [Cu(2)(L(C4))(4)(EtOH)(2)]·2(CH(2)Cl(2)) (3) complexes. When the reaction of L(C1)(-) with Cu(2)(O(2)CCH(3))(4)(H(2)O)(2) was carried out at -20 °C in the presence of pyridine, [Cu(2)(L(C1))(4)(py)(4)]·2(CH(2)Cl(2)) (4) was produced. At the core of complexes 1-3 lies the square Cu(2)(O(2)CR)(4) "paddlewheel" secondary building unit, where the two copper centers have a nearly square pyramidal geometry with methanol or ethanol occupying the axial coordination sites. Complex 4 contains a different type of dimeric core generated by two κ(1)-bridging carboxylate ligands. Additionally, two terminal carboxylates and four trans situated pyridine molecules complete the coordination environment of the five-coordinate copper(II) centers. In all four compounds, robust π···π stacking interactions of the naphthalimide rings organize the dimeric units into two-dimensional sheets. These two-dimensional networks are organized into a three-dimensional architecture by two different noncovalent interactions: strong π···π stacking of the naphthalimide rings (also the pyridine rings for 4) in 1, 3, and 4, and intermolecular hydrogen bonding of the coordinated methanol or ethanol molecules in 1-3. Magnetic measurements show that the copper ions in the paddlewheel complexes 1-3 are strongly antiferromagnetically coupled with -J values ranging from 255 to 325 cm(-1), whereas the copper ions in 4 are only weakly antiferromagnetically coupled. Typical values of the zero-field splitting parameter D were found from EPR studies of 1-3and the related known complexes [Cu(2)(L(C2))(4)(py)(2)]·2(CH(2)Cl(2))·(CH(3)OH), [Cu(2)(L(C3))(4)(py)(2)]·2(CH(2)Cl(2)) and [Cu(2)(L(C3))(4)(bipy)]·(CH(3)OH)(2)·(CH(2)Cl(2))(3.37) (L(C3)(-) = (1,8-naphthalimido)butanoate)), while its abnormal magnitude in [Cu(2)(L(C2))(4)(bipy)] was qualitatively rationalized by structural analysis and DFT calculations.  相似文献   

19.
本文选择了2-羟基-1-萘醛与水合肼形成的席夫碱,[(HO)(C10H6)CH=N-N=CH(C10H6)(OH)],作为配体,设计组装了双核三螺旋的三价铁配合物。配合物中每一个铁离子以准八面体的配位方式分别与三个NO双齿单元配位, 三个配体分别桥联两个金属形成特定的三螺旋构型。分子内和分子间的π-π堆积作用对螺旋体的形成和堆积方式起着十分重要的作用。作为对照,本文还报道了配体的晶体结构。  相似文献   

20.
合成并表征了配合物1,[Zn2(EBTC)(BPDO)(DMSO)(H2O)2]n,其中EBTC为1,1′-苯乙炔-3,3′,5,5′-四羧酸根,BPDO为4,4′-二吡啶基1,1′-二氧化物,DMSO为二甲亚砜。1沿着b轴的方向具有类似于三腿梯子状的链状结构,链与链之间通过氢键作用和π-π堆积作用形成了三维超分子结构。在室温条件下1表现出了荧光性质。  相似文献   

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