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1.
Hydrothermal synthesis has afforded a pair of divalent cobalt coordination polymers containing meta-substituted benzenedicarboxylate and 4,4′-dipyridylamine (dpa) ligands, in which the length of the pendant arms on the anionic components dictates the overall dimensionality. [Co(1,3-phda)(dpa)(H2O)]n (1, 1,3-phda = 1,3-phenylenediacetate) possesses a ruffled (4,4) rhomboid grid 2-D layered structure with an 5-connected sqp supramolecular net. Use of a meta-substituted benzenedicarboxylate with shorter pendant arms generated {[Co(1,3-bdc)(dpa)]·3H2O}n (2, 1,3-bdc = 1,3-benzenedicarboxylate), which displays a 3-D network structure with 658 topology. Antiferromagnetic coupling, in conjunction with zero-field splitting, was evident across the supramolecular Co-O-H?O-Co patterns in 1 and the syn-syn bridged {Co(OCO)}2 dimeric units in 2.  相似文献   

2.
Hydrothermal synthesis has afforded a family of three structurally related metal phthalate (pht) 1-D coordination polymers incorporating the kinked dipodal organodiimine 4,4′-dipyridylamine (dpa), with a general formulation of [L2M(dpa)2M(H2O)4] · H2O (L = pht, M = Co, 1, M = Ni, 2; L = 4-methylphthalate (4-mpht), M = Co, 3). Single crystal X-ray diffraction of 1 and 2 revealed the presence of one-dimensional (1-D) polymeric chains consisting of [M(H2O)4]2+ and [M(pht)2]2− subunits linked through dpa tethers. These chains in turn conjoin into pseudo 2-D layers and 3-D networks via extensive supramolecular hydrogen bonding pathways. An extremely similar structure is observed for 3 despite the presence of the bulkier methyl group substituent. 1-3 were further characterized via infrared spectroscopy and elemental and thermogravimetric analysis. 1-3 represent the first dicarboxylate coordination polymers incorporating dpa tethering ligands.  相似文献   

3.
Hydrothermal synthesis has afforded a series of divalent copper coordination polymers with substituted glutarate ligands and the rigid rod tether 4,4′-bipyridine (bpy): {[Cu(Hdmg)2(bpy)]·H2O}n (1, dmg = 3,3-dimethylglutarate), {[Cu2(dmg)(bpy)2](ClO4)]n (2), [Cu2(emg)2(bpy)]n (3, emg = 3-ethyl, 3-methylglutarate) and [Cu2(cda)2(bpy)]n (4, cda = 1,1-cyclopentanediacetate). All materials were characterized by single-crystal X-ray diffraction. Compound 1 manifests μ2-oxygen bridged [Cu2(Hdmg)4] “X”-patterns connected into a ribbon motif by bpy linkers. On the other hand, 2 possesses mixed-valence [CuICuIICuIICuI] tetrameric clusters bridged by dmg ligands and pillared into an 8-connected body-centered cubic (bcu) cationic lattice by bpy linkers. Compounds 3 and 4 are structurally very similar, displaying chain motifs with {Cu2(CO2)4} paddlewheels connected by dicarboxylates, in turn conjoined into (4,4)-grid coordination polymer layers by bpy tethers. Variable temperature magnetic data indicate the presence of very strong antiferromagnetic coupling within the {Cu2(CO2)4} paddlewheels in the latter two complexes, with g = 2.30(2) and J = −352(3) cm−1 for 3 and g = 2.35(2) and J = −352(5) cm−1 for 4. Significant structural contrasts are evident when compared to previously reported divalent copper/4,4′-bipyridine coordination polymers with unsubstituted or 2-methyl substituted glutarate ligands.  相似文献   

4.
Hydrothermal synthesis has afforded two divalent metal coordination polymers incorporating tridentate 2,6-pyridinedicarboxylate (PDC) ligands and the kinked dipodal organodiimine 4,4′-dipyridylamine (dpa), {[Ni(PDC)(dpa)(H2O)] · 2H2O} (1) and {[Zn(PDC)(dpa)] · 3H2O} (2), which were characterized by single crystal X-ray diffraction and spectral and thermogravimetric analyses. Although both 1 and 2 display one-dimensional (1-D) polymeric chain motifs, the different coordination environments (octahedral in 1, distorted square pyramidal in 2) provoke divergence in the structures and aggregations of the chain subunits. Compound 1 manifests both polycatenation and interdigitation of its 1-D polymeric chains, while 2 exhibits only interdigitation, resulting in widely disparate morphologies for water molecule-bearing channels within the extended structures. Compound 1 possesses three distinct channel types occupied by isolated water molecules. Compound 2 presents only one type of channel, larger than those in 1, filled with D(5) discrete-chain water molecule aggregations. In both cases the co-crystallized water molecules are anchored to the coordination polymer matrix by hydrogen bonding involving PDC carboxylate oxygen atoms and the central amine unit of the dpa ligands. These supramolecular interactions are crucial for stability, as 1 and 2 both undergo irreversible loss of crystallinity upon dehydration.  相似文献   

5.
Slow diffusion conditions have afforded a pair of cobalt isothiocyanate coordination polymers incorporating the flexible and hydrogen-bonding capable organodiimines N,N′-bis(3-pyridylmethyl)piperazine (3-bpmp) and N,N′-bis(4-pyridylmethyl)piperazine (4-bpmp), which were characterized by single-crystal X-ray diffraction and spectral and elemental analysis. While both [Co(NCS)2(3-bpmp)2]n (1) and {[Co(NCS)2(H2O)2(4-bpmp)] · 2H2O}n (2) possess one-dimensional (1-D) coordination polymer units, the donor disposition within the organodiimine promotes significant structural disparities. Compound 1 displays a 1-D double-chain motif, where each cobalt ion is bridged by two exobidentate 3-bpmp ligands. In contrast, compound 2 manifests a single chain pattern, with only one tethering 4-bpmp ligand joining adjacent cobalt ions. Extensive hydrogen-bonding patterns within the structure of 2 results in an intriguing supramolecular 2-D (3,4)-connected layer with (4.62)2(42.62.82) topology. Thermal properties of these materials are also discussed.  相似文献   

6.
Divalent cobalt coordination polymers containing both ortho-phenylenediacetate (ophda) and rigid dipyridyl ligands 4,4′-bipyridine (bpy) or 1,2-bis(4-pyridyl)ethylene (dpee) display different topologies depending on carboxylate binding mode, tether length, and inclusion of charged species. [Co(ophda)(H2O)(dpee)]n (1) displays a common (4,4) grid layer motif. Use of the shorter bpy tether afforded {[Co2(ophda)2(bpy)3(H2O)2][Co(bpy)2(H2O)4](NO3)2·2bpy·7H2O}n (2) or [Co(ophda)(bpy)]n (3) depending on cobalt precursor. Compound 2 manifests 5-connected [Co2(ophda)2(bpy)3(H2O)2]n pillared bilayer slabs with rare 4862 SnS topology and entrained [Co(bpy)2(H2O)4]2+ complex cations. The 3-D coordination polymer 3 has an uncommon 4,6-connected binodal (4462)(446108) fsc topology, and shows ferromagnetic coupling (J = +1.5(2) cm−1) along 1-D spiro-fused [Co(OCO)2]n chain submotifs.  相似文献   

7.
Hydrothermal synthesis has afforded a family of four coordination polymers containing divalent nickel or cobalt and pendant-arm pyridylcarboxylate ligands. Utilizing 3-pyridylacetic acid and appropriate metal precursors produced [M(3-pyrac)2(H2O)2] phases (M = Co (1); M = Ni (2)), while 3-pyridylpropionic acid generated [M(3-pyrprop)2(H2O)2] coordination polymers (M = Co (3); M = Ni (4)). Single crystal X-ray diffraction revealed that 1-4 all display discrete 2-D layers with (4,4)-topology, anchored via bridging 3-pyridylcarboxylate ligands bearing monodentate carboxylate termini. Intralamellar hydrogen bonding between the aquo ligands and unligated carboxylate oxygen atoms is observed within 1-4. The pseudo 3-D structures of 1-4 are further assembled via stacking of individual neutral layers by interlayer hydrogen bonding. Thermal properties are also discussed.  相似文献   

8.
Two novel coordination polymeric complexes [Co(pzca)2(H2O)]n (1) and [Mn(pzca)2]n (2) (pzca=2-pyrazinecarboxylate) have been synthesized by hydrothermal reaction of M(CH3COO)2·4H2O (M=Co, Mn) and 2-pyrazinecarboxylic acid. The complex 1 displays an infinite zigzag chain structure in which each cobalt(II) center was coordinated by three nitrogen and three oxygen atoms to generate a CoN3O3 octahedral geometry. The existence of hydrogen bond leads to the formation of the interpenetrating stacking structure. Complex 2 indicates a two-dimensional layer structure through the linkage of bridging oxygen atom of pzca ligand. Each Mn(II) center exhibits a distorted octahedral coordination environment with four oxygen atoms and two nitrogen atoms. The distances of adjacent Mn(II) atoms are 3.503 and 5.654 Å, respectively. The magnetic property analyses reveal that both complexes show weak antiferromagnetic exchange interactions between the metal centers.  相似文献   

9.
Two isothiocyanate coordination polymers constructed from the conformationally flexible tethering ligand 3,3′-bipyridine (3,3′-bpy) and divalent metal cations have been prepared and characterized via single crystal X-ray diffraction, infrared spectroscopy and elemental analysis. [Co(NCS)2(3,3′-bpy)2] (1), wherein the isothiocyanate ligands are coordinated in a trans fashion, manifests stacked two-dimensional (2-D) rhomboid grid layered motifs. In contrast, [Ni(NCS)2(3,3′-bpy)2] (2) possesses a doubly interpenetrated adamantoid three-dimensional (3-D) network despite the presence of trans isothiocyanate ligands. Thus, a metal cation-based control of coordination polymer dimensionality has been revealed in this system, reflective of different donor dispositions allowed by the conformational flexibility of the exobidentate 3,3′-bpy ligand. The 3-D framework of 2 decomposes at a temperature ∼40 °C higher than the 2-D network of 1.  相似文献   

10.
Hydrothermal synthesis has afforded divalent cadmium coordination polymers containing isophthalate (ip) or 5-methylisophthalate (mip) dicarboxylate ligands and bis(4-pyridylformyl)piperazine (4-bpfp) or bis(4-pyridylmethyl)homopiperazine (4-bpmh) tethers. {[Cd2(ip)2(H2O)2(4-bpfp)]·7H2O}n (1) displays a (4,4) grid topology based on {Cd2O2} dimeric clusters, along with “infinite” water molecule tapes with rare T4(0)A(1) classification. {[Cd(mip)(H2O)(4-bpfp)]·3H2O}n (2) also exhibits (4,4) grid layers but with 2D + 2D → 3D mutual inclined interpenetration instead of parallel stacking. [Cd4(ip)4(4-bpmh)2]n (3) has tetrameric {Cd4(ip)4} cluster units linked by ip and 4-bpmh ligands into a unique self-penetrated 3,5,5,5-connected tetranodal net with (4.82)(436285)(446482)(4.5648) topology. {[Cd2(mip)2(H2O)2(4-bpmh)]·2H2O}n (4) possesses a structure similar to that of 1, without the aggregated water molecule tapes. All four materials emit visible light upon ultraviolet excitation, ascribed to ligand-based electronic transitions.  相似文献   

11.
Two novel lanthanide(III) two-dimensional (2D) coordination polymers [Ln2(PDC)2(OH)2(H2O)2] · H2O (Ln = Eu (1) and Tb (2), H2PDC = pyridine-3,4-dicarboxylic acid) have been prepared under hydrothermal conditions and characterized by elemental analysis, IR, TGA and single-crystal X-ray diffraction. Compounds 1 and 2 crystallize in the triclinic system, space group , they are isostructural and exhibit the same two-dimensional topological network constructed by PDC-connected Ln-O-Ln double chains. Photoluminescence properties of the compounds 1 and 2 have been investigated in the solid state at room temperature.  相似文献   

12.
Five lanthanide coordination polymers with composition {[Ln(pzdc)1.5(H2O)3] · 0.5H2O}, (Ln = Pr, 1; Nd, 2; Sm, 3; Eu, 4; Gd, 5; pzdc = 2,5-pyrazinedicarboxylate), have been synthesized by reacting Ln(NO3)3 · 6H2O with 2,5-pyrazinedicarboxylic acid under hydrothermal condition in the absence of additional base and characterized by elemental analysis, IR spectra and TG analysis, as well as single-crystal X-ray diffraction. They crystallize isostructurally in the triclinic space group P-1 and the cell parameters agree with the ionic radii of the Ln(III) ions. Each trivalent rare earth ion is nine coordinate in an N2O7 environment. The ligand 2,5-pyrazinedicarboxylate adopts three coordination modes, through which the lanthanide ions are linked together to form an infinite three dimensional structure. A 1D channel exists along the (1 0 0) direction which accommodates uncoordinated water by hydrogen bonds. Heating of 4 at 120 °C evacuated the uncoordinated water while retaining its single crystallinity with only minor change in cell parameters (crystal 6, [Eu(pzdc)1.5(H2O)3]). This hydrophilic ultramicroporous channel is selective to accommodate water only among common solvents, which has some potential interest for solvent separation.  相似文献   

13.
Hydrothermal synthesis has afforded a pair of divalent copper coordination polymers containing the kinked and hydrogen-bonding capable imine 4,4′-dipyridylamine (dpa) and aromatic dicarboxylates, {[Cu(iph)(dpa)]·0.5H2O}n (1, iph = isophthalate) and [Cu(tdc)(dpa)]n (2, tdc = 2,5-thiophenedicarboxylate). Compounds 1 and 2 contain orthogonally disposed parallel sets of 1-D [Cu(iph)]n and [Cu(tdc)]n chains, respectively, containing dicarboxylate-bridged dinuclear {CuOCO}2 units. The chain motifs are joined by tethering dpa ligands to construct uncommon non-interpenetrated 3-D CdSO4 lattices (658 topology) in both cases. Variable temperature magnetic studies show the presence of weak antiferromagnetic coupling within the {CuOCO}2 dimers in both complexes, with J = −2.66(3) and −1.68(5) cm−1 for 1 and 2, respectively.  相似文献   

14.
Two new 4f-3d heterometallic coordination polymers [Gd2Co(L1)3(ox)(H2O)4]·2.5H2O (1, L1 = pyridine-2,5-dicarboxylate anion, ox = oxalate dianion) and [GdNi(L2)2(ox)0.5(H2O)3]·3H2O (2, L2 = pyridine-2,3-dicarboxylate anion) were successfully synthesized under hydrothermal conditions. In compound 1, one dimensional heterometallic and lanthanide infinite sheets were constructed with sole L1 spacers and L1-ox mixed bridges, respectively. While similar one dimensional heterometallic infinite sheet and normal lanthanide infinite zigzag chain were formed based on sole L2 and L2-ox mixed bridges, respectively in compound 2. Both of the two compounds exhibited new and interesting three dimensional topologies. In addition, the magnetic properties of the two compounds were analyzed via solid-state dc magnetic susceptibility measurements.  相似文献   

15.
A new coordination polymer, [Zn2(mal)(1,10-phen)Cl]n (1), (mal = malate, 1,10-phenanthroline), has been synthesized with malic acid and fumaric acid which are generated from maleic acid under hydrothermal reactions. At about the same condition, we get [Cd(fma)(2,2′-bpy)(H2O)]n (2) (fma = fumarate, 2,2′-bpy=2, 2′-bipyridine). The diverse products illustrate that the carbon-carbon doublebond of the maleic acid has two kinds of reaction trends under different conditions. Complex 1, which displays a two-dimensional (4, 8) lattice-type network, is formed from Zn and maleic through the addition reaction with water molecule. If the Zn is changed by Cd, at the same reaction condition with 1, a two-dimensional supramolecular network complex 2 is formed through the conformation transform reaction. To our knowledge, a lot of coordination polymers have been constructed from malic acid and fumaric acid directly; however, these kinds of complexes have seldom been synthesized from maleic acid under hydrothermal reaction. As is known, the rigid carbon-carbon double bond makes maleic acid lead to some unique structural features which the saturated aliphatic acid does not possess. To illustrate this clearly, a simple one dimensional complex 3, [Cd(glut)(1,10-phen)(H2O)]n (glut = glutarate), is synthesized. Furthermore, complex 1 and complex 3 exhibit intense photoluminescent property at room temperature.  相似文献   

16.
By pH-value adjustment, the reactions of zinc salt, 1,3,5-benzenetricarboxylic acid (H3btc) and 4,4′-bipyridine (bpy) yield three coordination polymers, formulated as [Zn3(btc)2(bpy)(H2O)2]n (1), [Zn(Hbtc)(bpy)(H2O)]n · 3nH2O (2) and [Zn(Hbtc)(bpy)(H2O)]n · 4nH2O (3), respectively. The structure of 1 is a 3D network containing channels filled with bpy ligands. Compound 2 consists of twofold interpenetrating (10,3)-b networks, while compound 3 is a 2D layer structure. The fluorescent studies reveal that they exhibit intense violet luminescence in solid state.  相似文献   

17.
Six fluconazole-bridged cobalt(II) coordination polymers, namely [Co(HFlu)2(H2O)2](ClO4)2 (1), [Co(HFlu)2(H2O)(AcO)](AcO)·2C2H5OH (2), [Co(HFlu)2Cl2]·2C2H5OH (3), [Co3(Flu)2(acac)4]·C2H5OH (4), [Co(HFlu)2(malo)(H2O)]·3H2O (5), and [Co(HFlu)2(fum)(H2O)2]·H2O (6) (HFlu = 2-(2′,4′-difluorophenyl)-1,3-bis(1,2,4-triazol-1-yl)-propan-2-ol, AcOH = acetate acid, Hacac = acetylacetonate, H2malo = malonate acid, H2fum = fumaric acid), have been synthesized and structurally characterized, and the thermal, fluorescent and magnetic properties investigated. The crystal structures display the one-dimensional cationic double-bridged chain consisting of 20-membered macrocycles to be parallel in 1 and perpendicular in 2. The structure of 3 consists of two-dimensional neutral rhombic grid in bc plane with (4,4) topology and alternative P/M helices intersecting at the Co sites along b direction. Complex 4 shows one-dimensional polymeric chain, in which binuclear Co2(Flu)2(acac)2 units act as bridging blocks to link Co(acac)2 nodes through triazolyl nitrogen atoms. The structure of 5 shows dimeric 20-membered macrometallacyclic motif. Complex 6 shows HFlu-bridged one-dimensional chain, which is stabilized by hydrogen-bonding interactions to produce alternative hydrophobic and hydrophilic architecture. Complexes 1-3 and 5-6 exhibit the similar electronic absorption and fluorescent spectra as those of HFlu, while complex 4 shows a fluorescent quenching phenomenon. Fluorescence titration of HFlu suggests that the fluorescent intensities at the maximal emission decrease upon the addition of Co(acac)2. The variable-temperature magnetic measurement of 4 reveals weak ferromagnetic interaction combined with the spin-orbit coupling effect in the 1-D Co(II) chain.  相似文献   

18.
2,6-Dimethyl-4-phenylpyridine-3,5-dicarboxylic acid (H2mppdc, H2L) is firstly employed in coordination chemistry. Two metal-organic coordination polymers with a general formula of M2L2(4,4′-bpy)x(H2O)4−2x (M = Zn or Co, x = 1 or 2) are assembled from H2L, 4,4′-bipyridine, zinc and cobalt salt under hydrothermal conditions, and characterized by single-crystal X-ray diffraction analyses. Of the crystal structures of title compounds, L ligands, limited in the environment from 4,4′-bipyridine, array in head-to-head and head-to-tail modes which are corresponding to the 1D (1) and 3D (2) polymeric structures, respectively. Interesting disorders occur in the crystal lattice of compound 1. And compound 2 has a 3D 42 · 610 · 83 topology. Solid-state H2L and 1 have expected photoluminescence at room temperature.  相似文献   

19.
Four divalent metal coordination polymers containing bis(4-pyridylmethyl)piperazine (4-bpmp) and the ortho-dicarboxylate ligands phthalate (pht) or 4-methylphthalate (mpht) have been prepared by solvent diffusion or hydrothermal methods. {[Cu2(pht)2(H4-bpmp)2(H2O)2](NO3)2·H2O}n (1) and {[Cu2(pht)2(H4-bpmp)2(H2O)2](SO4)·2H2O}n (2) possess chiral cationic layer motifs formed by the junction of [Cu(H2O)(pht)]n chains by tethering curled-conformation H4-bpmp+ ligands. {[Co(pht)(H2O)(4-bpmp)]·5.5H2O}n (3) displays a (4,4) grid constructed from anti-syn carboxylate-bridged {Co2(H2O)2(pht)2} dimeric clusters linked by open-conformation 4-bpmp ligands. {[Cd2(mpht)2(H2O)2(4-bpmp)(H4-bpmp)]ClO4·4H2O}n (4) manifests cationic layered motifs based on neutral [Cd2(H2O)2(mpht)2] dinuclear units with {CdOC4O}2 12-membered circuits, linked by open-conformation 4-bpmp and H4-bpmp+ ligands. Variable-temperature magnetic data indicate likely concomitant zero-field splitting and ferromagnetic coupling in 3. Violet light emission is observed when 4 is subjected to ultraviolet irradiation.  相似文献   

20.
Two lanthanide coordination polymers, {[La2(bpdc)3(H2O)4]·(H2O)4}n (1) and {[Sm2(bpdc)3(H2O)2]·(H2O)5}n (2) (H2bpdc = 2,2′-bipyridine-3,3′-dicarboxylic acid) have been obtained by hydrothermal synthesis. Single-crystal X-ray diffraction shows that 1 and 2 are two-dimensional network structures based on the zigzag chains which are linked by bpdc ligands, forming the first examples of binary lanthanide polymers with bpdc. It is unprecedented that the adjacent zigzag chains are symmetrical in mirror images with the arraying form of ?ABAB?. In 1 and 2, lanthanide ion are all nine-coordinate and bpdc ligands exhibit different kinds of coordination modes. The 1-D infinite water chain in 1 and pentameric water ring in 2 have been found between lattice water molecules. Thermo-gravimetric analyses of 1 and 2 display considerable thermal stability. Photoluminescent properties of 1 and 2 are discussed.  相似文献   

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