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1.
This work reports structural investigations on two metal complexes of the functionalized (p‐carboxylatobenzyl)‐bis(2‐picolyl)amine ligand 1 (HL). The complex {[HLPdCl]Cl × H2O}2 ( 2Pd ) has a square‐planar coordination around the Pd ion. It forms discrete dimers by intermolecular hydrogen bonding involving the protonated ligand HL. The coordination around the Zn2+ ion in {[(H2O)LZn]CF3SO3 × 2 H2O} ( 3Zn ) is best described as distorted trigonal‐bipyramidal. The N3O2 ligand sphere is composed of three nitrogen atoms from the bpa ligand, one water molecule, and a carboxylate oxygen atom from a neighbouring molecule, thus forming infinite chains along the crystallographic a axis. Further intermolecular interactions are based on the same (H2O)2(anion)2 motif as for 2Pd , but whereas the former forms discrete dimers, 3Zn forms a more complicated two‐dimensional coordination polymer with additional intermolecular hydrogen bonds.  相似文献   

2.
Nanostructures of a new coordination polymer of divalent lead with the ligand 2, 9‐dimethyl‐1, 10‐phenanthroline (dmp) containing the first Pb2‐(μ‐ClO4)2 motif, [Pb2(dmp)2(μ‐N3)2(μ‐ClO4)2]n ( 1 ), was synthesized by a sonochemical method that produces the coordination polymers at nano size. The new nanostructure was characterized by scanning electron microscopy, X‐ray powder diffraction, IR, 1H NMR and 13C NMR spectroscopy, and elemental analysis. Compound 1 was structurally characterized by single‐crystal X‐ray diffraction and the single‐crystal X‐ray data shows that the coordination number of PbII ions is six, (PbN4O2), with two N‐donor atoms from aza‐aromatic base ligands and four O‐donors from two perchlorate anions and two N‐donors from two azide anions. It has a “stereo‐chemically active” electron lone pair, and the coordination sphere is hemidirected. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The chains interact with each other through π–π stacking interactions creating a 3D framework. The structure of the title complex was optimized by density functional theory calculations. Calculated structural parameters and IR spectra for the title complex are in agreement with the crystal structure. The PbO nanoparticles were obtained by thermolysis of 1 at 180 °C with oleic acid as a surfactant. The average diameter of the nanoparticles was estimated by the Scherrer equation to be 23 nm. The morphology and size of the prepared PbO samples were further observed using SEM.  相似文献   

3.
The single crystal X‐ray analysis of a novel thiophene‐2,5‐dicarboxylic acid (H2Tda) Manganese(II) coordination polymer, {Mn23‐Tda)2(μ‐H2O)(H2O)2(bipy)]·DMF}n, shows two different types of Mn2+‐ions with environment of Mn1O6 and Mn2O4N2, and the complex is a two‐dimensional polymer as a result of bridging (Tda)2? ligands and by connecting the carboxylate‐ and water‐bridged {Mn2(μ‐Tda)2(μ‐H2O)} nodes.  相似文献   

4.
The 1:2 adduct lead(II) complexes with 1, 10‐phenanthroline (phen) containing three different anions, [Pb(phen)2(CH3COO)X] (X=NCS, NO3 and ClO4), have been synthesized and characterized by CHN elemental analysis, IR‐, 1H‐ and 13C NMR spectroscopy. The structure of [Pb(phen)2(CH3COO)(ClO4)] was determined by single crystal X‐ray analysis. The Pb atom of the monomeric complex is coordinated by four nitrogen atoms of two 1, 10‐phenanthroline ligands and two oxygen atoms of the acetate ligand to form an irregular octahedron. The arrangement of the 1, 10‐phenanthroline and acetate ligands, exhibits a coordination gap around the PbII ion, possibly occupied by a stereochemical electron active lone pair on lead(II), which results in a hemidirected lead compound. The π‐π stacking interaction between the parallel aromatic rings may help to increase the coordination ‘gap’ around the PbII ion.  相似文献   

5.
The title compound, [Pb(C4H3N2S)2]n, was prepared by the reaction of [Pb(OAc)2]·3H2O (OAc is acetate) with pyrimidine‐2‐thione in the presence of triethylamine in methanol. In the crystal structure, the PbII atom has an N4S4 coordination environment with four ligands coordinated by N‐ and S‐donor atoms. This compound shows that the pyrimidine‐2‐thiolate anion can lead to a three‐dimensional network when the coordination number of the metal ion can be higher than 6, as is the case with the PbII ion. This compound presents only covalent bonds, showing that despite the possibility of the hemidirected geometries of PbII, the eight‐coordinated ion does not allow the formation of an isolated molecular structure with pyrimidine‐2‐thiolate as the ligand.  相似文献   

6.
The single crystal X‐ray data of a mixed anions complex of PbII with 1,10‐Phenantroline, [Pb(phen)(O2CCH3)‐ (O2NO)], shows the complex to be polymeric as a result of acetate ligand bridging. The Pb atom has an asymmetrical eightfold coordination of two nitrogen atoms of the 1,10‐phenanthroline ligand and six oxygen atoms of the nitrate and acetate anions. The arrangement of the 1,10‐phenantroline ligand, acetate and nitrate anions suggest a gap in the coordination around the PbII ion, occupied possibly by a stereoactive lone pair of electrons on lead(II) where the coordination around the lead atoms is hemidirected. There is a π‐π stacking interaction between the parallel aromatic rings of an adjacent chain in the compound which might help to increase the ‘gap' in the coordination around the PbII ion.  相似文献   

7.
Two new mixed‐anion zinc(II) and cadmium(II) complexes of 3‐(2‐pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine (PDPT) ligand, [Zn(PDPT)2Cl(ClO4)] and [Cd(PDPT)2(NO3)(ClO4)], have been synthesized and characterized by elemental analysis, IR‐ and 1H NMR spectroscopy. The single crystal X‐ray analyses show that the coordination number in these complexes is six with four N‐donor atoms from two “PDPT” ligand and two of the anionic ligands, ZnN4ClOperchlorate, CdN4OnitrateOperchlorate. Self‐assembly of these compounds in the solid state via ππ‐stacking interactions is discussed.  相似文献   

8.
In the coordination polymer catena‐poly[[[diaqua[5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylato‐κ2N3,O4]lead(II)]‐μ‐5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylato‐κ3N3,O4:N2] dihydrate], {[Pb(C10H6N3O4)(H2O)2]·2H2O}n, the two 5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylate ligands have different coordination modes, one being terminal and the other bridging. The bridging ligand links PbII cations into one‐dimensional coordination polymer chains. The structure is also stabilized by intra‐ and interchain π–π stacking interactions between the pyridine rings, resulting in the formation of a two‐dimensional network. Extensive hydrogen‐bonding interactions lead to the formation of a three‐dimensional supramolecular network.  相似文献   

9.
A new nanostructured coordination polymer of divalent lead with the ligand 2,9‐dimethyl‐1,10‐phenanthroline (dmp), [Pb(dmp)(μ‐N3)(μ‐NO3)]n ( 1 ), was synthesized by sonochemical methods. The polymer was characterized by scanning electron microscopy, X‐ray powder diffraction, IR, 1H NMR, and 13C NMR spectroscopy, and elemental analyses. Compound 1 was structurally characterized by single‐crystal X‐ray diffraction. The single‐crystal analysis shows that the coordination number of PbII ions is seven, (PbN4O3) has a “stereo‐chemically active” electron lone pair, and the coordination sphere is hemidirected. The chains interact with each other through π–π stacking interactions to create a 3D framework. The structure of the title complex was optimized by density functional calculations. The calculated structural parameters and the IR spectrum of the title complex are in agreement with the crystal structure.  相似文献   

10.
The hydrothermal reactions of Ni(II), 1,2,3‐benzenetricarboxylic acid (1,2,3‐H3btc) and 4,4′‐bipyridine (4,4′‐bpy)/1,2‐bis(4‐pyridyl)ethane (bpa) yield two layered nickel(II) coordination polymers, [Ni2(1,2,3‐btc)(OAc)‐(4,4′‐bpy)2(H2O)]·2H2O ( 1 ) and [Ni(ip)(bpa)] ( 2 ) (ip=isophthalate), respectively. Both complexes are 2‐D coordination network based on 1‐D Ni‐carboxylate chains. The 1,2,3‐btc ligand adopts 3‐bridging mode in complex 1 , but transformed to isophthalate (ip) ligand through decarboxylation in 2 . The formation of the two complexes indicates that hydrothermal conditions andin‐situ ligand reaction have significant effect on constructing coordination polymers.  相似文献   

11.
Mercury(II) complexes with 4,4′‐bipyridine (4,4′‐bipy) ligand were synthesized and characterized by elemental analysis, and IR, 1H‐ and 13C‐NMR spectroscopy. The structures of the complexes [Hg3(4,4′‐bipy)2(CH3COO)2(SCN)4]n ( 1 ), [Hg5(4,4′‐bipy)5(SCN)10]n ( 2 ), [Hg2(4,4′‐bipy)2(CH3COO)2]n(ClO4)2n ( 3 ), and [Hg(4,4′‐bipy)I2]n ( 4 ) were determined by X‐ray crystallography. The single‐crystal X‐ray data show that 2 and 4 are one‐dimensional zigzag polymers with four‐coordinate Hg‐atoms, whereas 1 is a one‐dimensional helical chain with two four‐coordinate and one six‐coordinate Hg‐atom. Complex 3 is a two‐dimensional polymer with a five‐coordinate Hg‐atom. These results show the capacity of the Hg‐ion to act as a soft acid that is capable to form compounds with coordination numbers four, five, and six and consequently to produce different forms of coordination polymers, containing one‐ and two‐dimensional networks.  相似文献   

12.
Three coordination polymers (CPs) based on the 5‐[4‐(1H‐imidazol‐1‐yl)phenyl]‐1H‐tetrazole ( HL ) ligand, namely, [Cu(μ2‐ L )(μ4‐pbda)(H2O)] ( 1 ), [Cu2(μ‐Hbtc)(H2btc)(μ3‐OH)(μ4‐ HL )] ( 2 ) and [Cu53‐ L )(μ4‐ L )(μ3‐ip)(μ3‐OH)(H2O)2] · 2H2O ( 3 ) (H2pbda = 1,4‐benzenedicarboxylic acid, H3btc = 1,3,5‐benzenetricarboxylic acid, H2ip = isophthalic acid) were hydrothermally synthesized and structurally characterized. Complex 1 represents “weave”‐type 2D layers consisting of wave‐like 1D chains and 1D straight chains, which are further connected by hydrogen bonds to form a 3D supramolecular structure. Complex 2 exhibits a uninodal (4)‐connected 2D layer with a point symbol of {44 · 62}, in which the L ligand can be described as μ5‐bridging and the H2btc ions display multiple kinds of coordination modes to connect CuII ions into 1D “H”‐type Cu‐H2btc chains. In complex 3 , 2D Cu‐ L layers with two kinds of grids and 1D “stair”‐type Cu‐ip chains link each other to construct a 3D {412 · 63} framework, which contains the pentanuclear subunits. Deprotonated degree and coordination modes of carboxylate ligands may consequentially influence the coordination patterns of main ligands and the final structures of complexes 1 – 3 . Furthermore, electrochemical behaviors and electrocatalytic activities of the title complexes were analyzed at room temperature, suggesting practical applications in areas of electrocatalytic reduction toward nitrite and hydrogen dioxide in aqueous solutions, respectively.  相似文献   

13.
In the title coordination polymer, [Cd2(SO4)2(C13H8N4)(H2O)2]n, there are two crystallographically independent CdII centres with different coordination geometries. The first CdII centre is hexacoordinated by four O atoms of four sulfate ligands, one water O atom and one N atom of a 1H‐imidazo[4,5‐f][1,10]phenanthroline (IP) ligand, giving a distorted octahedral coordination environment. The second CdII centre is heptacoordinated by four O atoms of three sulfate ligands, one water O atom and two N atoms of one chelating IP ligand, resulting in a distorted monocapped anti‐trigonal prismatic geometry. The symmetry‐independent CdII ions are bridged in an alternating fashion by sulfate ligands, forming one‐dimensional ladder‐like chains which are connected through the IP ligands to form two‐dimensional layers. These two‐dimensional layers are linked by interlayer hydrogen bonds, leading to the formation of a three‐dimensional supramolecular network.  相似文献   

14.
Two new two‐dimensional CuII and MnII coordination polymers of 5‐aminobenzene‐1,3‐dicarboxylic acid (abdc) ligand, [Cu(μ4‐abdc)(DMF)]n and {[Mn(μ4‐abdc)(H2O)]·H2O}n, have been synthesized and characterized by elemental analysis and IR‐ spectroscopy. The single crystal X‐ray analyses show that the coordination number in these complexes is six, CuO5Cu and MnO5N. The compounds are structurally diverse and the coordination polymer obtained from copper show significant copper–copper interaction while the manganese coordination polymer shows Mn–Namino bond.  相似文献   

15.
3‐(Pyridin‐4‐yl)acetylacetone (HacacPy) acts as a pyridine‐type ligand towards CdII and HgII halides. With CdBr2, the one‐dimensional polymer [Cd(μ‐Br)2(HacacPy)Cd(μ‐Br)2(HacacPy)2] is obtained in which five‐ and six‐coordinated CdII cations alternate in the chain direction. Reaction of HacacPy with HgBr2 results in [Hg(μ‐Br)Br(HacacPy)], a polymer in which each HgII centre is tetracoordinated. In both compounds, each metal(II) cation is N‐coordinated by at least one HacacPy ligand. Equimolar reaction between these CdII and HgII derivatives, either conducted in ethanol as solvent or via grinding in the solid state, leads to ligand redistribution and the formation of the well‐ordered bimetallic polymer catena‐poly[[bromidomercury(II)]‐μ‐bromido‐[aquabis[4‐hydroxy‐3‐(pyridin‐4‐yl)pent‐3‐en‐2‐one]cadmium(II)]‐di‐μ‐bromido], [CdHgBr4(C10H11NO2)2(H2O)]n or [{HgBr}(μ‐Br){(HacacPy)2Cd(H2O)}(μ‐Br)2]. HgII and CdII cations alternate in the [100] direction. The HacacPy ligands do not bind to the HgII cations, which are tetracoordinated by three bridging and one terminal bromide ligand. The CdII centres adopt an only slightly distorted octahedral coordination. Three bromide ligands link them in a (2 + 1) pattern to neighbouring HgII atoms; two HacacPy ligands in a cis configuration, acting as N‐atom donors, and a terminal aqua ligand complete the coordination sphere. Classical O—H…Br hydrogen bonds stabilize the polymeric chain. O—H…O hydrogen bonds between aqua H atoms and the uncoordinated carbonyl group of an HacacPy ligand in a neighbouring strand in the c direction link the chains into layers in the (010) plane.  相似文献   

16.
Three coordination polymers, {[Cd(3‐bpd)2(NCS)2]×C2H5OH}n ( 1 ), {[Cd(3‐bpd)(dpe)(NO3)2]×(3‐bpd)}2 ( 2 ), {[Cd(dpe)2(NCS)2]×3‐bpd×2H2O}n ( 3 ) (3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene; dpe = 1,2‐bis(4‐pyridyl)ethane), were prepared and structurally characterized by a single‐crystal X‐ray diffraction method. In compound 1 , each Cd(II) ion is six‐coordinate bonded to six nitrogen atoms from four 3‐bpd and two NCS? ligands. The 3‐bpd acts as a bridging ligand connecting the Cd(II) ion to generate a 2D layered metal‐organic framework (MOF) by using a rhomboidal‐grid as the basic building units with the 44 topology. In compound 2 , the Cd(II) ion is also six‐coordinate bonded to four nitrogen atoms of two 3‐bpd, two dpe and two oxygen atoms of two NO3? ligands. The 3‐bpd and dpe ligands both adopt bis‐monodentate coordination mode connecting the Cd(II) ions to generate a 2D layered MOF by using a rectangle‐grid as the basic building units with the 44 topology. In compound 3 , two crystallographically independent Cd(II) ions are both coordinated by four nitrogen atoms of dpe ligands in the basal plane and two nitrogen atom of NCS? in the axial sites. The dpe acts as a bridging ligand to connect the Cd(II) ions forming a 2D interpenetrating MOFs by using a square‐grid as the basic unit with the 44 topology. All of their 2D layered MOFs in compounds 1 ‐ 3 are then arranged in a parallel non‐interpenetrating ABAB—packing manner in 1 and 2 , and mutually interpenetrating manner in 3 , respectively, to extend their 3D supramolecular architectures with their 1D pores intercalated with solvent (ethanol in 1 or H2O in 3 ) or free 3‐bpd molecules in 2 and 3 , respectively. The photoluminescence measurements of 1 ‐ 3 reveal that the emission is tentatively assigned to originate from π‐π* transition for 1 and 2 and probably due to ligand‐center luminescence for compounds 3 , respectively.  相似文献   

17.
In the title polymeric heterometallic compound, {[Cu3Gd(C6H4NO2)3Cl3(H2O)2]·0.5H2O}n, comprising copper(I) and gadolinium(III) cations bridged by nicotinate (nic) ligands and chloride anions, the GdIII centers display a bicapped trigonal prismatic geometry, defined by six carboxylate O atoms and two water molecules. For copper(I), one Cu center is three‐coordinated by three chloride ions and displays a trigonal–planar geometry; the other two Cu centers are four‐coordinated and display a very distorted tetrahedral geometry. The chloride anions act in μ2‐ and μ3‐bridging modes, linking the CuI ions into an infinite chain. The nic ligand exhibits a tridentate coordination mode, with the carboxylate O atoms linking to two GdIII ions and the N atom linking to one CuI ion. Thus, a novel three‐dimensional heterometallic coordination polymer is constructed from Gd–carboxylate subunits and Cu—Cl chains. In addition, intra‐ and intermolecular O—H...O and O—H...Cl hydrogen bonds are also observed within the three‐dimensional structure. Topologically, the framework represents an unusual 3,6‐connected (4.82)3(410.65) net.  相似文献   

18.
The asymmetric unit of the title coordination polymer, [Gd2(C7H4O5S)2(C2O4)(H2O)6]n or [Gd(2‐SB)(ox)0.5(H2O)3]2n (2‐SB is 2‐sulfonatobenzoate and ox is oxalate), (I), consists of one GdIII ion, one 2‐SB anion, three coordinated water molecules and one half of an ox ligand. The ox ligand is located on a crystallographic inversion centre. The GdIII centre shows a distorted tricapped trigonal–prismatic coordination formed by nine O atoms from two 2‐SB anions, one ox ligand and three coordinated water molecules. The carboxylate and sulfonate groups of the 2‐SB anions adopt μ2‐η12 and μ1‐η001 coordination modes to link two GdIII ions, generating a centrosymmetric binuclear [Gd2(2‐SB)2(H2O)6]2− subunit. The ox ligand acts as a bridge, linking the binuclear [Gd2(2‐SB)2(H2O)6]2− subunits into a one‐dimensional chain structure parallel to the b axis. Furthermore, extensive O—H...O hydrogen bonds connect the chains into a three‐dimensional supramolecular architecture.  相似文献   

19.
A novel 1D polymeric lead(II) complex containing the first Pb2‐(μ‐N3)2 motif, [Pb(phen)(μ‐N3)(μ‐NO3)]n (phen = 1,10‐phenanthroline), has been synthesized and characterized. The single‐crystal X‐ray data showed the coordination number of Pb2+ ions to be eight (PbN4O4) with the Pb2+ ions having “stereo‐chemically active” electron lone pairs; the coordination sphere is hemidirected. The chains interact with each other via π‐π interactions to create a 3D framework.  相似文献   

20.
In the title coordination polymer, [Zn2(C14H8N2O4)2(C12H10N2)]n, the asymmetric unit contains one ZnII cation, two halves of 2,2′‐(diazene‐1,2‐diyl)dibenzoate anions (denoted L2−) and half of a 1,2‐bis(pyridin‐4‐yl)ethene ligand (denoted bpe). The three ligands lie across crystallographic inversion centres. Each ZnII centre is four‐coordinated by three O atoms of bridging carboxylate groups from three L2− ligands and by one N atom from a bpe ligand, forming a tetrahedral coordination geometry. Two ZnII atoms are bridged by two carboxylate groups of L2− ligands, generating a [Zn2(CO2)2] ring. Each loop serves as a fourfold node, which links its four equivalent nodes via the sharing of four L2− ligands to form a two‐dimensional [Zn2L4]n net. These nets are separated by bpe ligands acting as spacers, producing a three‐dimensional framework with a 4664 topology. Powder X‐ray diffraction and solid‐state photoluminescence were also measured.  相似文献   

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