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1.
Four new silver(I) coordination polymers, namely [Ag(NH2pyz)(ox)0.5]n (1), [Ag(NH2pyz)(adp)0.5·2H2O]n (2), [Ag2(NH2pyz)2(bdc)·H2O]n (3) and [Ag2(NH2pyz)2.5(ndc)]n (4) [NH2pyz = 2-aminopyrazine, ox = oxalate anion, adp = adipate anion, bdc = 1,4-benzenedicarboxylate anion, ndc = 1,4-naphthalenedicarboxylate anion] have been synthesized by solution phase ultrasonic reactions of Ag2O with heterocyclic NH2pyz and various dicarboxylates under ammoniacal conditions. The complexes were characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. Complex 1 is a three-dimensional (3D) framework with an α-ThSi2 topology. Complex 2 features a 2D 44-sql net involving infinite 1D double Ag-NH2pyz chains and flexible adp anion spacers. Complex 3 is a 3D framework in which 1D single Ag-NH2pyz chains are pillared by bdc anions to form a 2D 63-hcb network, adjacent 2D networks are packed into a 3D framework through bridging O atoms of dbc anions. Complex 4 is a 2D structure built from infinite 1D stair-like chains containing finite Ag4(NH2pyz)5 subunits. The results show that the structural diversity of the complexes result from the nature of the dicarboxylate ligands. The photoluminescence properties of the complexes were also investigated in the solid state at room temperature.  相似文献   

2.
Three supramolecular coordination polymers (SCPs) [(AgSCN)2L] {L = 4,4′-bipyridine (bpy) (1), trans-1,2-bis(4-pyridyl)ethylene (tbpe) (2) and phenazine (phenz) (3)} have been synthesized and structurally characterized by single-crystal X-ray diffraction. Synthesis was affected in H2O/acetonitrile/NH3 media at room temperature. The bpy, tbpe and phenz bipodal ligands adopt different conformations which would affect the skeleton of the (AgSCN)n building blocks that allow the interconnection of the (AgSCN)n fragments and propagation of the network structure in three dimensions. Supramolecular interactions such as hydrogen-bonding, argentophilic interaction and π–π stacking play an important role in the assembly of these coordination polymers.  相似文献   

3.
The alkyl chain-linked diimidazolium (or dibenzimidazolium) salts, 1,1′-diethyl-4,4′-tetramethylene-diimidazolium-diiodide (L1H2·I2) and 1,1′-diethyl-3,3′-trimethylene-dibenzimidazolium-diiodide (L2H2·I2), and their silver(I) and copper(II) coordination polymers, [L1AgI]n (1) and [L2Cu2I4]n (2), have been prepared and characterized. Complex 1 is a 1D helical polymer generated by bidentated carbene ligands (L1) and Ag(I) atoms. The 1D polymer of 2 is formed by bidentated carbene ligands (L2) and coplanar quadrilateral Cu2I2 units. 3D supramolecular frameworks in the crystal packings of 1 and 2 are formed via intermolecular weak interactions, including C–H···π contacts, ππ interactions and C–H···I hydrogen bonds.  相似文献   

4.
Reaction of the twisted pyridyl dithioether ligand bis(4-pyridylthio)methane (4bpytm) with silver(I) salts afforded four complexes with 1:1 stoichiometries, namely [Ag(4bpytm)](NO3) (1), [Ag(4bpytm)](ClO4) (2) and [Ag(4bpytm)](ClO4) ½CH2Cl2 ½dmf (2·Solv), [Ag(CH3COO)(4bpytm)]·H2O (3) and [Ag(CF3COO)(4bpytm)] (4). X-ray structural analysis of these complexes showed that one-dimensional structures are obtained for 1, 2·Solv and 4 whereas a two-dimensional network is formed in 3. The ligand 4bpytm acts as an N,N′-bis(monodentate) bridging system in all cases except in 3, where an unprecedented coordination mode is obtained with the ligand acting in a tridentate manner using its two pyridine nitrogen atoms and a sulfur atom. The coordination polymers are assembled through secondary contacts: Ag···Ag in 4, Ag···S in 1, 2·Solv and 4, Ag···O in 2·Solv, and hydrogen bonding interactions between crystallization water that join the polymeric layers in 3. All of these weak interactions link the low-dimensional complexes to give high-dimensional supramolecular structures and further stabilize the crystal structures in the solid state.  相似文献   

5.
Two new coordination polymers, [Cu(BDC)(L1)0.5]n (1) and [Cu(BDC)(L2)0.5]n (2) [H2BDC=5-methyl-1,3-benzenedicarboxylic acid, L1=1,4-bis(2-methyl-imidazol-1-yl) butane and L2=1,4-bis(1-imidazol-yl)-2,5-dimethylbenzene], were synthesized from Cu(II), H2BDC, and L1/L2. The carboxylate groups in 1 and 2 are bis-monodentate. By changing the N-donor ligands, 1 and 2 exhibit different topologies from a rob topological net to a twofold interpenetrating pcu net; however, they possess the same paddle-wheel secondary building unit in which Cu(II) has square-pyramidal geometry. The thermal stabilities of 1 and 2 are investigated.  相似文献   

6.
Two pyridinecarboxylato-bridged coordination polymers {[Co(pbc)2(H2O)] · H2O} n (1) and [Co(pbc)2] n (2) (Hpbc = 3-pyrid-3-ylbenzoic acid) have been synthesized by the hydrothermal method and characterized by X-ray single crystal diffraction. In 1, pbc? ligands link two Co(II) centers as μ2-N,O and μ2-N,O,O. Co(II) is six coordinate, octahedral. In 2, Co(II) is coordinated by four oxygens and two nitrogens. The ligands are μ2-N,O,O and μ3-N,O,O. Through different pbc? ligands, 2 generates a 3-D network composed of six-connected nodes. Compound 2 exhibits good photoluminescence, whereas 1 is nonemissive at room temperature.  相似文献   

7.
Four coordination polymers, [Ag(L1)](m-Hbdc) (1), [Ag(L1)]2(p-bdc)?·?8H2O (2), [Ag(Hbtc)(L1)][Ag(L1)]?·?2H2O (3) and [Ag2(L2)2](OH-bdc)2?·?4H2O (4), where L1?=?1,1′-(1,4-butanediyl)bis(imidazole), L2?=?1,2-bis(imidazol-1-ylmethyl)benzene, m-H2bdc?=?1,3-benzenedicarboxylic acid, p-H2bdc?=?1,4-benzenedicarboxylic acid, H3btc?=?1,3,5-benzenetricarboxylic acid, and OH–H2bdc?=?5-hydroxisophthalic acid, were synthesized under hydrothermal conditions. Compound 1 contains a–Ag-L1–Ag-L1–chain and a hydrogen-bonding interaction induced–(m-Hbdc)-(m-Hbdc)–chain. Compound 2 consists of two independent–Ag-L1–Ag-L1–chains. P-bdc anions are not coordinated. Hydrogen bonds form a 3D supramolecular structure. A novel (H2O)16 cluster is formed by lattice water molecules in 2. Compound 3 contains a–Ag-L1–Ag-L1–and a–Ag(Hbtc)-L1–Ag(Hbtc)-L1–chain. The packing diagram shows a 2D criss-cross supramolecular structure, with?π?···?π?and C–H ···?π?interactions stabilizing the framework. Compound 4 contains a [Ag2(L2)2]2+ dimer with hydrogen-bonding,?π?··· π, and Ag ··· O interactions forming a 3D supramolecular framework. The luminescent properties for these compounds in the solid state are discussed.  相似文献   

8.
Two pyridinecarboxylato-bridged coordination polymers [Mn(pbc)2] n (1) and [Mn(pbc)2(H2O)2] n (2) (Hpbc = 3-pyrid-3-ylbenzoic acid) have been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. X-ray diffraction analysis reveals that pbc? adopts two coordination modes: μ 2-N, O, O and μ 3-N, O, O in 1 and as diconnectors linking two Mn(II) centers through μ 2-N, O in 2. Compound 1 is a dinuclear Mn2(pbc)2 metallocycle. Compound 2 is a double-stranded chain running along a.  相似文献   

9.
Two new coordination polymers, [Mn(dpa)(2,2′-bipy)] n (1) and [Ni(dpa)(2,2′-bipy)] n (2) (H2dpa = 3,4′-biphenyl-dicarboxylic acid, 2,2′-bipy = bipyridine), have been synthesized and structurally characterized by elemental analysis, IR, and X-ray diffraction. Single-crystal X-ray analyses revealed that 3,4′-diphenic acid acts as a bridging ligand, exhibiting rich coordination modes to link metal ions: μ 2η 1: η 1, μ 1η 1: η 1, and μ 1 –η 1: η 0. Compound 1 demonstrates a 1-D zigzag chain. Compound 2 is a 1-D helical chain. In 1 and 2, there exist intermolecular π–π stacking interactions and non-covalent interactions responsible for the stabilization of the supramolecular structure. In 1, the Mn(II) chains exhibit a weak antiferromagnetic interaction.  相似文献   

10.
When the polymeric complex [Ag(im)]n (Him = imidazole) is reacted with PPh3 (PPh3 = triphenylphosphine), it yields the [Ag22-im)2(PPh3)3]n and [Ag(μ2-im)(PPh3)2]n species, shown to contain wavy chains of metal ions, singly bridged by N,N′-exo-bidentate imidazolate ligands. The former, crystallised as the CH2Cl2 solvate, contains two non-equivalent silver(I) ions, differing in the number of coordinated phosphines (one, in trigonal planar stereochemistry, or two, having tetrahedral geometry). The latter has a unique independent silver(I) ion in a tetrahedral environment, with two coordinated PPh3 ligands. The reactivity of known silver(I) azolates with PPh3, as well as the solution behaviour and (when available) the crystal structures of the corresponding derivatives are taken into consideration for a due comparison.  相似文献   

11.
Two new coordination polymers, [Ag2(barb)(pipet)]n (1) and {Na3[Ag2(barb)2](pippr)·2H2O}n (2) (where H2barb, pipet and Hpippr are 5,5-diethylbarbituric acid, N-piperidineethanol and 1,3-bis(4-piperidyl)propane, respectively) have been synthesized and characterized by elemental analysis, IR, thermal analysis and X-ray single-crystal diffraction techniques. Silver(I) ions in complexes 1 and 2 are bridged by barb dianions, leading to one-dimensional coordination polymers. In 1, the barb ligand acts as a tetradentate bridging ligand, while in 2 as a bidendate bridging ligand. The pipet ligand behaves as a bidentate chelating donor, whereas the pippr anion is not involved in coordination and remains as a counter-ion. The one-dimensional chains of 1 and 2 are further extended into supramolecular networks. Spectral and thermal analysis data for 1 and 2 are in agreement with the crystal structures.  相似文献   

12.
Five mixed ligands coordination polymers [Ag4(apym)2(pma)·(H2O)2]n (1), {[Ag4(dmapym)4(pma)·(H2O)2]·(H2O)6}n (2), [Ag2(apyz)2(H2pma)·(H2O)4]n (3), {[Ag4(apyz)2(pma)·(H2O)2]·(H2O)2}n (4) and [Ag4(NH3)8(pma)·(H2O)6]n (5) (apym = 2-aminopyrimidine, dmapym = 4, 6-dimethyl-2-aminopyrimidine, apyz = 2-aminopyrazine, H4pma = pyromellitic acid) were synthesized and characterized. For 1 and 2, as the substituents change from H to methyl, the dimensions of 12 decrease from three-dimension (3D) to one-dimension (1D) due to the steric effect of methyl groups. For 3 and 4, as the ratios of Ag2O/apyz/pma vary from 1:1:1 to 2:1:1, the structure of 3 is a 1D ladder structure built from Ag-apyz double chains and pma anions, while the structure of 4 is a two-dimension (2D) grid. As excess ammonia is added to above four reaction systems, the structure of 5 contains unprecedented {[Ag(NH3)2]+}n chains and pma anions. The substituent on the pyrimidyl ring, ratios of reactants, solvent systems and ligand isomers intensively influence the coordination environments of metal ion and the coordination modes of the carboxyl group, and thus determine the structures of the coordination polymers. The photoluminescent properties of 15 were also investigated.  相似文献   

13.
A silver(I) complex of saccharinate (sac) with pyrazine (pyz), [Ag(sac)(pyz)] n , has been synthesized and characterized by elemental analysis, IR, thermal analysis, and single-crystal X-ray diffractometry. The complex crystallizes orthorhombic space group Pnma with unit cell parameters of a = 13.0073(9) Å, b = 6.4907(6) Å, c = 13.4007(9) Å, V = 1131.37(15) Å3, and Z = 4. [Ag(sac)(pyz)] n is a one-dimensional coordination polymer, in which the sac ligand acts as a monodentate ligand through the N atom and the trigonal silver centers are linked by the bridging pyz ligands. The individual chains are connected into two-dimensional supramolemular network by aromatic π(sac)···π(pyz) stacking interactions. The FTIR spectrum of [Ag(sac)(pyz)] n has been recorded in the region and 4,000–400 cm?1. The optimized geometry, frequency, and intensity of the vibrational bands of [Ag(sac)(pyz)] n were obtained by density functional theory (DFT) at the B3LYP level. The vibrational frequencies were calculated and the scaled values have been compared with the experimental FTIR data. The observed and calculated frequencies are found to be in good agreement.  相似文献   

14.
The use of dimeric [RhCl(CO)2]2 as acceptor unit in the construction of mono-, bi- and three-dimensional metallosupramolecular structures is reported.The reaction of the dimer with the alkynylgold complex [Au(CCC5H4N)(CNC6H4O(O)CC6H4OC10H21)] resulted in the mononuclear rhodium complex 1, through an unexpected transfer of the isonitrile ligand from the gold to the rhodium centres.The reaction of the linear unit [RhCl(CO)2]2(μ-4,4′-bipy) (3) with the diphosphine 1,4-bis(diphenylphosphino)butane (dppb) yielded the simultaneous formation of both metallomacrocycles [RhCl(CO)(dppb)]2 (4) and {[RhCl(CO)]2(μ-4,4′-bipy)}2(μ-dppb)2 (5). The use of a diphosphine with smaller bite angle, 1,1′-bis-(diphenylphosphino)methane, (dppm) formed the three-dimensional {[RhCl(CO)]2(μ-4,4′-bipy)}2(μ-dppm)4 complex (6) that incorporates four diphosphine units connecting two [RhCl(CO)2]2(μ-bipy) linear edges. PM3 semi-empirical method has been used to calculate the optimised geometry of compound 6.  相似文献   

15.
A silver(I)-saccharinato (sac) complex with nicotinamide (nia), [Ag(sac)(nia)] n has been synthesized and characterized by elemental analysis, IR spectroscopy, DTA-TG analyses and single crystal X-ray diffractometry. The complex crystallizes in monoclinic space group P21/n with unit cell parameters of a=7.0258(4) Å, b=24.3784(10) Å, c=8.4301(5) Å, β=109.407(5)°, V=1361.85(13) Å3 and Z=4. [Ag(sac)(nia)] n contains [Ag(sac)(nia)] units, which are doubly bridged by both nia and sac ligands, leading to a linear one-dimensional polymeric chains running along the a axis. The silver(I) ion has a highly distorted AgN2O2 tetrahedral geometry and the coordination polymer exhibits relatively short intra-chain ligand supported Ag···Ag separations of 3.1593(4) Å. The one-dimensional chains are crosslinked by N–H···O hydrogen bonds and aromatic π(sac)···π(nia) stacking interactions to generate a two-dimensional layer structure. IR spectra and thermal analysis data are in agreement with the crystal structure.  相似文献   

16.
Three new coordination polymers {[Ni(bte)2(NCO)2](H2O)} n (1), {[Ni(bte)2(N3)2](H2O)} n (2) and {[Ag(bte)2](NO3)} n (3) (bte?=?1,2-bis(1,2,4-triazol-1-yl)ethane) were synthesized and characterized by X-ray crystallography, IR and thermogravimetric analysis. The coordination geometry of the Ni(II) atom is distorted octahedral, coordinated equatorially by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands, and axially by two nitrogen atoms from two isocyanate anions in 1 and azide anions in 2, respectively. The structures of 1 and 2 are both polymeric, with 18-membered spiro-fused rings and each 18-membered ring involving two inversion-related bte molecules. The coordination geometry of the Ag(I) atom in 3 is distorted tetrahedral, formed by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands. Each bte ligand links two Ag(I) atoms and forms a two-dimensional undulated (4,4) network in 3.  相似文献   

17.
Two ligands, 2-{5,5-dimethyl-3-[2-(pyridin-3-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L1) and 2-{5,5-dimethyl-3-[2-(pyridin-2-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L2), were synthesized. By reaction of mercury thiocyanate with L1 and L2, respectively, coordination polymers [Hg(L1)(μ1,3-SCN)2]n (1), [Hg(L1)2(μ1,3-SCN)2]n (2), and [Hg(L2)(μ1,3-SCN)(SCN)]n (3) with different structures and topologies were obtained. In 1, the thiocyanate shows μ1,3-SCN bridging coordination, and adjacent Hg(II) ions are bridged by two μ1,3-SCN ions to form an infinite chain with the remaining position of five-coordinate Hg(II) occupied by L1. In 2, the thiocyanate has the same coordination as 1. However, Hg(II) has octahedral coordination with two L1 involved in coordination. An unusual feature of 3 is the presence of two types of thiocyanates, one has a S-terminal ligand and the other has a μ1,3-SCN bridge. The mercury(II) in 3 is four-coordinated by L2 and three thiocyanates. Luminescent properties and thermal stabilities of 1–3 were studied.  相似文献   

18.
The effect of the length of alkane spacer in diphosphines on the nuclearity of Ag(I) complexes containing dialkyl dithiophosphates (dtp) ligands has been investigated. 1,1-Bis(diphenylphosphino)methane (dppm) yielded tetranuclear [Ag4(dppm)2{S2P(OEt)2}4] (1), [Ag4(dppm)2{S2P(OiPr)2}4] (3), trinuclear [Ag3(dppm)3{S2P(OEt)2}2](PF6) (2), and a dinuclear [Ag2(dppm)2{S2P(OiPr)}](PF6) (4). The increase in spacer length from one methylene in dppm to two in 1,2-bis(diphenylphosphino)ethane (dppe) resulted in the formation of polymeric, [Ag(dppe){S2P(OR)2}] (R = Et, 5a and 5a′; iPr, 5b), and [Ag43-Cl)(dppe)1.5{S2P(OR)2}3] (R = Et, 6a; iPr, 6b). Compounds 5a, 5b, 6a and 6b were reported earlier [C.W. Liu, B.-J. Liaw, L.-S. Liou, J.-C. Wang, Chem. Commun. (2005) 1983]. Further increase in the chain length to four methylene units in 1,4-bis(diphenylphosphino)butane (dppb) yielded dppb-bridged polymers, [Ag(dppb){S2P(OEt)2}] (7) and [Ag2(dppb){S2P(OEt)2}2] (8). In all the polynuclear compounds, diphosphines acted as P,P′-bridging ligands, while the dtp ligands (S,S′-donors) adopted varieties of coordination patterns: S,S′-chelating (5, 7), S,S′-bridging (4), bimetallic-triconnective, μ221 (1, 3, 8), bimetallic-diconnective, μ22 (2, 3) and trimetallic-triconnective, μ321 (6). Some of the complexes exhibit argentophilicity with Ag?Ag distances in the range, 2.918-3.360 Å. Concomitant bridging of two silver atoms either by dppm and dtp ligands (1, 3 and 4) or two dtp ligands (8) lead to close silver-silver contacts. The diphosphines (dppe and dppb) with longer spacer appeared to favor 1D or 2D polymers due to the flexibility of the spacer within the diphosphine unit by adopting anti conformation as opposed to syn conformation of the dppm linker is revealed in complexes.  相似文献   

19.
Nano-structures of two new Pb(II) three-dimensional coordination polymers, [Pb2(4-pyc)2I2(H2O)]n (1), {4-Hpyc = 4-pyridinecarboxilic acid} and [Pb(3-pyc)I]n (2), {3-Hpyc = 3-pyridinecarboxilic acid} were synthesized by sonochemical method. The new nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Compounds 1 and 2 were structurally characterized by single crystal X-ray diffraction and are three-dimensional coordination polymers. The thermal stability of compounds 1 and 2 both their bulk and nano-size were studied by thermal gravimetric and differential thermal analyses and compared. PbO block-structures were obtained by calcination of the nano-structures of compounds 1 and 2 at 400 °C.  相似文献   

20.
Reactions of AgO2C2F3 with (E)-N-(pyridylmethylene)aniline in which the pyridyl N is in the p- or m-position yielded two 1-D coordination polymers, [(AgO2C2F3)2(La)2]n (La = (E)-2,6-diisopropyl-N-(pyrid-3-ylmethylene)aniline) (1) and [(AgOC2F3)2(Ld)2]n (Ld = (E)-2,6-diisopropyl-N-(pyrid-4-ylmethylene)aniline) (5), and three discrete complexes, [(AgO2C2F3)2(La)4] (2), [AgO2C2F3(Lb)2] (Lb = (E)-N-(pyrid-4-ylmethylene)aniline) (3) and [(AgOC2F3)2(Lc)4] (Lc = (E)-2,6-dimethyl-N-(pyrid-4-ylmethylene)aniline) (4). The structures were determined by MS, FT-IR and NMR spectroscopies, elemental analysis and single crystal XRD. 1 is an organometallic coordination polymer with silver in η1-arene coordination, but is a discrete dimeric complex 2 when crystallized from warm diethylether. The geometries around silver(I) in 1 and 4 are tetrahedral, ‘inverted seesaw’ in 2 and T-shaped in 3 and in all the anion seems to play a role. Ag(I) centers in 5 have distorted trigonal bipyramid and inverted seesaw geometries. The trifluoroacetate anions in these complexes display variable monodentate and short bridging coordination patterns. All complexes absorb and strongly emit UV-Vis radiation at room temperature.  相似文献   

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