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1.
Divalent zinc coordination polymers containing bis(3‐pyridylmethyl)piperazine (3‐bpmp) and isophthalate ligands have been hydrothermally synthesized and structurally characterized by single‐crystal X‐ray diffraction. {[Zn(ip)(H3‐bpmp)]ClO4·4H2O}n ( 1 , ip = isophthalate) has twofold parallel interpenetrated (4,4) grid cationic coordination polymer nets, with unligated perchlorate ions and intriguing infinite water molecule chains. {[Zn2(NO2ip)3(H23‐bpmp)(H2O)5]·3H2O}n ( 2 , NO2ip = 5‐nitroisophthalate) exhibits a supramolecular lattice built from 1D chain motifs, revealing a significant dependence of topology on the steric bulk of the dicarboxylate ligand. Luminescent properties for 1 and 2 are also reported.  相似文献   

2.
Slow diffusion of aqueous cobalt thiocyanate or cadmium perchlorate and ethanolic solutions of 3,4′‐dipyridylketone (3,4′‐dpk) generated the coordination polymers {[Co(NCS)2(3,4′‐dpk)2]·2H2O}n ( 1 ) and {[Cd(H2O)2(3,4′‐dpk)2](ClO4)2·2H2O}n ( 2 ), which were structurally characterized by single‐crystal X‐ray diffraction. The structure of 1 consists of interdigitated neutral [Co(NCS)2(3,4′‐dpk)2]n (4,4) rectangular grid coordination polymer layers. However, compound 2 manifests cationic [Cd(H2O)2(3,4′‐dpk)2]n2n+ two‐dimensional (6,3) herringbone lattices connected through hydrogen bonding mediated by interlamellar unligated perchlorate anions. Upon excitation with ultraviolet radiation, 2 emits blue‐violet light, ascribed to π–π* transitions within the pyridyl rings of the 3,4′‐dpk ligands. Thermal decomposition behavior of 1 is also discussed.  相似文献   

3.
The cobalt‐formate coordination polymers {[Co(bpyph)(HCOO)2]8}n ( 1 ) (bpyph = 1,4‐bis(2‐(4‐pyridyl)ethenyl)benzene) and {[Co(HCONH2)2(HCOO)2]}n ( 2 ) have been prepared by interaction of Co(NO3)2 · 6 H2O in formamide solution with generation of formate anion by hydrolysis of the solvent. Coordination polymer 1 reveals an unprecedented example of “molecular multi‐rod cable” architecture, in which eight single “molecular wires” {[Co(bpyph)]}n are interlinked by bridging formate anions to give infinite octameric chains. The formate groups adopt mono‐, and bi‐ and tridentate bridging and chelate modes of coordination (Co–O 1.966–2.134 Å). The coordination geometry around the cobalt atoms is essentially dominated by the demands for most effective packing of parallel situated polycyclic aromatic ligands, with extensive CH…π, or edge‐to‐face stacking interactions within the single octameric chain as well as between the closest neighbours (C…C separations within this stack are ca. 3.50 Å).  相似文献   

4.
A series of five new ZnII and CdII mixed‐ligand coordination polymers, namely, {[Zn(L1)(4,4′‐bpy)] · (ClO4) · 2H2O} ( 1 ), {[Zn(L2)(4,4′‐bpy)0.5] · (ClO4)} ( 2 ), {[Zn(L3)(4,4′‐bpy)] · (NO3) · 2H2O} ( 3 ), {[Cd(L4)(4,4′‐bpy)0.5(NO3)] · 5H2O} ( 4 ), and {[Zn(L4)(4,4′‐bpy)] · Cl · H2O} ( 5 ) [4,4′‐bpy = 4,4′‐bipyridine, L1 = 4‐carboxy‐1‐(4‐carboxybenzyl)pyridin‐1‐ium chloride, L2 = 3‐carboxy‐1‐(4‐carboxybenzyl)pyridin‐1‐ium chloride, L3 = 4‐carboxy‐1‐(3‐carboxybenzyl)pyridin‐1‐ium chloride, and L4 = 3‐carboxy‐1‐(3‐carboxybenzyl)pyridin‐1‐ium chloride], were obtained by the reactions of the 4,4′‐bipyridine with four dicarboxylate zwitterionic pyridine ligands. Single‐crystal X‐ray structural analyses reveal that the five complexes demonstrate different molecular frameworks coming from various coordination modes and flexibilities of different dicarboxylate zwitterionic pyridine ligands and central metal atoms. Mononuclear twofold dinuclear 2D twofold interpenetrating net for 2 , four‐coordinate mononuclear twofold interpenetrating 2D layer for 3 , mononuclear 2D layer arranged in parallel and with large grids for 4 , and twofold trans interpenetrating 2D network for compound 5 . The structural diversities in 1 – 5 indicate that the nature of the ligands and the presence of different metal atoms have a great influence on central metal coordination modes and the structural topologies of the metal‐organic molecular architectures. In addition, π ··· π stacking interactions also play important roles in the final crystal packing and supramolecular frameworks. The powder X‐ray diffraction, elemental analysis, and photoluminescence properties of 1 – 5 were studied, which show that architectures play an important role in emission bands and intensities.  相似文献   

5.
The coordination polymers, {[Co(bbim)2(H2O)2](tcbdc) · 2H2O}n ( 1 ), {[Ni(tcbdc)(bbim)(H2O)2] · 2DMF}n ( 2 ), and {[Cu2(tcbdc)2(bbim)4] · 4H2O}n ( 3 ) [bbim = 1,1′‐(1,4‐butanediyl)bis(imidazole) and tcbdc2– = tetrachlorobenzene‐1,4‐dicarboxylate] were synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, luminescence, and single‐crystal X‐ray diffraction analysis. Complex 1 has a double‐stranded chain structure through doubly bridged [Co(bbim)2] units. Complex 2 exhibits two‐dimensional square grid, whereas complex 3 has a three‐dimensional porous network structure with an unprecedented 44 · 611 topological structure through interpenetrating square grid. The water molecules in complex 3 occupy the vacancy through three kinds of hydrogen bond interactions. Upon excitation at 370 nm, complexes 1 – 3 present solid‐state luminescence at room temperature.  相似文献   

6.
The reactions of Ln(NO3)3 · 6H2O and 4‐acetamidobenzoic acid (Haba) with 4,4′‐bipyridine (4,4′‐bpy) in ethanol solution resulted in three new lanthanide coordination polymers, namely {[Ln(aba)3(H2O)2] · 0.5(4,4′‐bpy) · 2H2O} [Ln = Sm ( 1 ), Gd ( 2 ), and Er ( 3 ), aba = 4‐acetamidobenzoate]. Compounds 1 – 3 are isomorphous and have one‐dimensional chains bridged by four aba anions. 4,4′‐Bipyridine molecules don’t take part in the coordination with LnIII ions and occur in the lattice as guest molecules. Moreover, the adjacent 1D chains in the complex are further linked through numerous N–H ··· O and O–H ··· O hydrogen bonds to form a 3D supramolecular network. In addition, complex 1 in the solid state shows characteristic emission in the visible region at room temperature.  相似文献   

7.
The 1D chain red luminescent europium coordination polymer: {[Eu2L6(DMF)(H2O)] · 2DMF · H2O}n ( I ) (L = 4‐chloro‐cinnamic acid anion, C9H6ClO2, DMF = N, N‐dimethylformamide) was synthesized by the reaction of Eu(OH)3 and 4‐chloro‐cinnamic acid ligand. The structure of the coordination polymer was determined by single‐crystal X‐ray diffraction analysis. It reveals that there exists two crystallographically nonequivalent europium atoms in each unit of this coordination polymer and Eu3+ ions are connected by two alternating bridging modes to form an endless polymer structure. The luminescent properties and energy transfer process in the complex are investigated at room temperature.  相似文献   

8.
以肉桂酸C9H8O2(HL)及其衍生物对位取代肉桂酸R-L(R=CH3,Cl,NO2,OCH3,OH)为配体,分别与Eu3+配位,得到系列Eu3+配合物。X-射线单晶解析结果表明:对甲基肉桂酸铕(1)和对氯肉桂酸铕(2)为一维高分子链,对硝基肉桂酸铕(3)为双核结构。通过FT-IR和UV-Vis光谱分析了配体在配位前后的变化。记录和解析了各配合物的荧光光谱,研究了对位取代基吸电子性和配位小分子对配合物发光性能的影响。  相似文献   

9.
Three coordination compounds, {[Co(btrp)2(H2O)2]?·?NO3?·?H2O} n (1), {[Co(btrp)2(H2O)2]?·?H2O?·?2H2btc} n (2), and {[Co(btrp)3]?·?2ClO4} n (3) (btrp?=?1,3-bis(1,2,4-triazol-1-yl)propane; H3btc?=?benzene-1,3,5-tricarboxylic acid), have been prepared via solvothermal method and characterized by single-crystal X-ray diffraction and elemental analyses. Compound 1 possesses a 1-D double-stranded chain composed of ribbons of 20-membered cycles. Binuclear water clusters link adjacent nitrate anions to form a 1-D supramolecular helix in the structure. Compound 2 has a 1-D double-stranded chain wherein free H2btc ligands constitute 1-D negative chains through classical hydrogen-bonding interactions (O–H?···?O). Compound 3 exhibits a triple-stranded 1-D chain. For 13, 3-D supramolecular structures are consolidated by interchain weak hydrogen-bonding interactions as well as electrostatic interactions.  相似文献   

10.
《Polyhedron》2001,20(15-16):1925-1931
The synthesis and structural characterization of novel organometallic coordination polymers are reported. The reaction of Cd(NO3)2 and 4,4′-bipy in CH3OH/H2O gave a 2D coordination network formulated as {[Cd(4,4′-bpy)2·(H2O)2](NO3)2·4H2O}10, which was used to capture an organic guest species (4-amino-benezopheone, C13H11NO (3)) to obtain {[Cd(4,4′-bpy)2(NO3)(H2O)]·NO3·(C13H11NO)2} (1). Using L (L=4,4′-trimethylenedipyridine) instead of 4,4′-bipy, {[Cd(L)2(H2O)2]·2H2O·2NO3·C13H11NO} (2) was synthesized, which has an interesting configuration.  相似文献   

11.
The reactions of cobalt acetates with tetrachloroterephthalic acid (H2BDC‐Cl4) in different solvents gave two polymeric and one mononuclear CoII complexes. X‐ray single‐crystal structural determination revealed that the ligand BDC‐Cl4 displays a reliable bridging tecton to construct diverse supramolecular architectures through coordinative bonds or secondary hydrogen‐bonding interactions. The complexes [Co(BDC‐Cl4)(DMF)2(EtOH)2]n ( 1 ) and {[Co(BDC‐Cl4)(DMF)2(MeOH)2] · 2DMF}n ( 2 ) demonstrate a one‐dimensional (1D) coordination motif with infinite CoII‐tetrachloroterephthalate chains, which are tuned by different binding solvent systems of DMF/ethanol (EtOH) and DMF/methanol (MeOH). [Co(DMF)2(H2O)4] · (BDC‐Cl4) ( 3 ) represents a two‐dimensional (2D) metallosupramolecular network by hydrogen‐bonded bridging between the aqua ligand of the mononuclear complex with the uncoordinated BDC‐Cl4 solvates. The spectroscopic, thermal, and fluorescent properties of 1 – 3 were also investigated.  相似文献   

12.
Two new one-dimensional coordination polymers {[Ni(L)(maleate)] · H2O} n (1) and {[Ni(L)(H2btc)] · 2DMF} n (L = cyclam, btc = 1,2,4,5-benzenetetracarboxylate, DMF = N,N-dimethylformamide) (2) have been synthesized and structurally characterized by single crystal X-ray diffraction. In the structures (1) and (2), the carboxylate groups of bridging ligands are coordinated to nickel(II) cyclams resulting in the formation of one-dimensional coordination polymers. In addition to the Ni–O bonds, it is observed that the hydrogen bonding interactions between the pre-organized N–H groups of the cyclams and bridging anions support the formation of coordination polymers in both complexes.  相似文献   

13.
Two coordination polymers, {[Zn(NiL)(DMA)(H2O)2] (DMA)(H2O)} n (1) (DMA?=?N,N-dimethylacetamide) and {[Zn2(NiL)2(DMF)(H2O)4]?·?3DMF} n (2) (DMF?=?N,N-dimethylformamide), have been prepared by reactions of Zn(NO3)2?·?6H2O and NiL in CH2Cl2-DMA–H2O and CH2Cl2-DMF–H2O, respectively. H2L denotes dimethyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo-9,10-benzo-[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate. Single-crystal X-ray diffraction analyses reveal that coordination geometries around Ni(II) are identical with slightly distorted square planar and all Ni–N bonds are very short. Complex 1 shows 1-D zigzag chain structure, while 2 has 1-D double-zigzag chains. The chains, which are packed parallel in 1 and 2, are interconnected by lattice solvent through O–H···O and C–H···O hydrogen bonds to form 3-D supramolecular networks. We discuss solvent effects on assembly of the two coordination polymers. The results reveal that coordinated solvent has influence on the assembly procedure.  相似文献   

14.
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one‐dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent MnII metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4‐oxidopyridine‐2,6‐dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag‐like geometry of the coordination polymer is stabilized by hydrogen bonds. O—H...O and C—H...O hydrogen bonds and water clusters consolidate the three‐dimensional network structure.  相似文献   

15.
Different kinds of counterions (such as NO3, ClO4, and Cl) play a special role in controlling the framework of coordination compounds. Using this strategy, 5‐aminotetrazole‐1‐propionic acid (Hatzp) was selected to react with praseodymium(III) nitrate or perchlorate in the same solvent system, producing two different coordination compounds, [Pr2(atzp)4(H2O)8] · 2NO3 · 2H2O ( 1 ) and [Pr2(atzp)6(H2O)2] · H2O ( 2 ). These compounds were structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray diffraction analysis revealed that compound 1 displays a dinuclear structure, whereas 2 shows a one dimensional zigzag chain framework. Furthermore, the luminescence properties of compounds 1 and 2 were investigated at room temperature in the solid state.  相似文献   

16.
Three 1H‐benzimidazole‐5‐carboxylate (Hbic)‐based coordination polymers, {[Ni(H2O)(Hbic)2] · 2H2O}n ( 1 ), {[Ni(H2O)2(Hbic)2] · 3H2O}n ( 2 ), and {[Co2(H2O)4(Hbic)4] · 4DMF · 3H2O}n ( 3 ) were obtained by reactions of the ligand H2bic and NiII or CoII salts in the presence of different structure directing molecules. They were structurally characterized by single‐crystal X‐ray diffraction, IR spectra, elemental analysis, thermal stability, luminescent, and magnetic measurements. Structural analysis suggests that the three polymers exhibit a 2D (4, 4) layer for 1 and 1D linear double chains for both 2 and 3 due to the variable binding modes and the specific spatial orientation of the Hbic ligand towards the different paramagnetic metal ions, which were further aggregated into different 3D supramolecular architectures by popular hydrogen‐bonding interactions. Weak and comparable antiferromagnetic couplings mediating by Hbic bridge are observed between the neighboring spin carriers for 2 and 3 , respectively. Additionally, complexes 1 – 3 also display different luminescence emissions at room temperature due to the ligand‐to‐metal charge transfer.  相似文献   

17.
Abstract. Two metal‐organic coordination polymers [Co(bmb)(btc)0.5]n( 1 ) and {[Zn(bmb)0.5(btc)0.5(H2O)] · 0.5bmb · H2O}n ( 2 ) [H4btc = benzene‐1, 2, 4, 5‐tetracarboxylic acid, bmb = 1, 4‐bis(2‐methylbenzimidazol‐1‐ylmethyl) benzene] were prepared under hydrothermal conditions. Single‐crystal X‐ray diffraction indicates that both complexes have a 2D framework structure with (4 · 62) (42 · 62 · 82) topology. Interestingly, the hydrogen bonds in 2 form a fascinating meso‐helix. The catalytic activity of 1 for oxidative coupling of 2, 6‐dimethylphenol (DMP) and the photoluminescence properties of 2 were investigated. Furthermore, the complexes were investigated by IR spectroscopy and thermogravimetric analysis.  相似文献   

18.
The title complex {[Co(dimb)2(H2O)2]·(NO3)2·(H2O)2}n ( 1 ) (dimb = 1,3‐di(imidazol‐1‐ylmethyl)‐5‐methylbenzene) has been hydrothermally synthesized by the reaction of dimb with Co(NO3)2·6H2O in aqueous solution. The cobalt(II) atoms are linked by bridging dimb ligands to form 2D corrugated and wavy networks containing Co4(dimb)4 macrocyclic motifs. Two neighboring independent layers interlinked each other in a parallel fashion to construct three‐dimensional structure by O–H···O, N–H···O and C–H···O hydrogen bonds. Magnetic measurement shows the weak antiferromagnetic interaction with a one‐dimensional chain model in the range of 5–300 K, with J of –0.68 cm−1.  相似文献   

19.
Four coordination polymers of the bidentate ligand 2,2′-dimethyl-4,4′-bipyridine-N,N′-dioxide (L), [La(L)(NO3)3(H2O)] n (1), {[Gd2(L)3(NO3)6]·6H2O} n (2), {[Sm(L)2(H2O)4]·3ClO4·2L·4H2O} n (3) and {[Nd(L)2(H2O)4]·3ClO4·2L·4H2O} n (4) have been synthesized by the diffusing solvent mixture method. Results of X-ray diffraction analysis reveal that 1, with a Ln/L stoichiometry of 1:1, displays a rare 3-D three-fold interpenetrating diamondoid framework, while 2 has a Ln/L stoichiometry of 1:1.5 and exhibits a polycatenane network with a {82,10} topology and large channels accommodated by water. Complexes 3 and 4, with Ln/L stoichiometry of 1:2, have 3-D two-fold interpenetrating diamondoid structures and large voids. Nonlinear optical property of 2 and luminescence of 3 were also investigated.  相似文献   

20.
Four metal‐organic frameworks (MOFs), {[Mn3.5L(OH)(HCOO)4(DMF)] · H2O} ( 1 ), {[In2.5L2O(OH)1.5(H2O)2] · DMF · CH3CN · 2H2O} ( 2 ), {[Pb4L3O(DMA)] · CH3CN} ( 3 ), and {[LaL(NO3)(DMF)2] · 2H2O} ( 4 ) were synthesized by utilizing the ligand 2,2′,6,6′‐tetramethoxy‐4,4′‐biphenyldicarboxylic acid (H2L) via solvothermal methods. All MOFs were characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction, thermogravimetric analysis, and infrared spectroscopy. In 1 , the Mn2+ ions are interconnected by formic groups in situ produced via DMF decomposition to form a rare 2D macrocyclic plane, which is further linked by L2– to construct the final 3D network. In 2 , 1D zip‐like infinite chain is formed and then interconnected to build the 3D framework. In 3 , a [Pb64‐O)2(O2C)10(DMA)2] cluster with a centrosymmetric [Pb64‐O)2]8+ octahedral core is formed in the 3D structure. In 4 , the La3+ ions are connected with each other through carboxylate groups of L2– to generate 1D zigzag chain, which is further linked by L2– to construct a 3D network with sra topology. Solid photoluminescence properties of 3 and 4 were also investigated.  相似文献   

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