Structural Systematics of 2/4-Nitrophenoxide Complexes of Closed-Shell Metal Ions. VI 4-Nitrophenoxides of Group 2

1998 ◽  
Vol 51 (8) ◽  
pp. 775 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Paloth Venugopalam ◽  
Allan H. White

Room-temperature single-crystal X-ray structure determinations are recorded for 4-nitrophenolate (4-np-) salts of Group 2 metal ions, variously hydrated, M(4-np)2.xH2O, M = Mg, Ca, Sr, Ba. Mg(4-np)2.8H2 O is monoclinic, P21/c, a 12·402(3), b 6·673(7), c 11·833(6) Å, β 93·70(3)°, Z = 2; conventional R on |F| was 0·041 for No 1995 independent ‘observed’ (I > 3σ(I)) reflections. Ca(4-np)2.4H2O is monoclinic, P21/c, a 13·109(8), b 3·644(1), c 21·181(8) Å, β 125·55(3)°, Z= 2, R 0·050 for No 1371. Sr(4-np)2.8H2O is monoclinic, P21/n, a 7·934(1), b 10·658(1), c 23·602(2) Å, β 91·36(1)°, Z = 4, R 0·038 for No 2050. Ba(4-np)2.8H2O is monoclinic P21/c, a 15·990(8), b 6·337(3), c 25·634(8) Å, β 126·1(3)°, Z = 4, R 0·021 for No 3115. The magnesium salt is ionic with [Mg(OH2)6]2+ cations and interleaved anion stacks up b. The calcium salt is a one-dimensional polymer with ... Ca(µ-O)2Ca(µ-O)2Ca ... spine, the bridges being phenolic oxygen atoms.trans-Coordinated water molecules make up six-coordination about the calcium, the anion planes stacking at the b spacing. The strontium adduct is also a one-dimensional polymer with a similar spine, but with water molecule oxygen atoms bridging, the nine-coordinate strontium environment being made up by a chelating nitro group and three unidentate water molecules. Coordinated anions stacked up a are interleaved by free anions. The barium salt is simply [Ba(4-np)(OH2)8]+ (4-np-), the ligand anion (semi)chelated through the nitro pair of oxygen atoms, again with interleaving anion/ligand stacking.

1998 ◽  
Vol 51 (8) ◽  
pp. 761 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Allan H. White

Room-temperature single-crystal X-ray studies are recorded for 2-nitrophenoxide salts of Group 2 metals, variously hydrated M(2-np)2.xH2O, M = Mg, Ca, Sr; the structure of the barium analogue has been previously recorded. Mg(2-np)2.2H2O is monoclinic, P21/a, a 7·377(1), b 7·518(1), c 12·877(3) Å, β 106·58(2)°, Z = 2; conventional R on |F| 0·13 for No 508 independent ‘observed’ (I > 3σ(I)) reflections. Ca(2-np)2.H2O is monoclinic, C2, a 25·92(1), b 7·176(3), c 3·660(4) Å, β 93·66(5)°, Z = 2, R 0·061 for No 541. M(2-np)2.4H2O, M = Ca, Sr, are isomorphous, monoclinic, C2/c, a ≈ 31·3, b ≈ 8·1, c ≈ 12·8 Å, β 103°, Z = 8; R was 0·056, 0·055 forNo 1988, 1744 respectively. The magnesium salt is a discrete molecular array disposed about a crystallographic inversion centre with chelating phenoxide ligands: trans-[Mg(2-np)2(OH2)2]. The calcium monohydrate salt is a novel one-dimensional polymer with a ... Ca(µ-O)2Ca(µ-O)2Ca ... spine, the ligand pairs chelating the calcium with phenoxide-O additionally bridging. The seven-coordinate calcium atoms lie on the crystallographic 2 axis with the water molecule, also on that axis, making up a seven-coordinate environment. The tetrahydrate is also a one-dimensional polymer with a similar spine, the bridging oxygen atoms derivative of water molecules. A chelating ligand and two further water molecules make up an eight-coordinate metal environment, with the free anions interleaving stacks of coordinated anions up c.


1998 ◽  
Vol 51 (8) ◽  
pp. 785 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Allan H. White

Room-temperature single-crystal X-ray structure determinations are recorded for a number of Group 2 4-nitrophenoxide acid salts, variously hydrated M(4-np)2.x(4-npH).yH2O. Ca(4-np)2.2(4-npH).8H2O is monoclinic, P 21/n, a 30·52(1), b 10·027(1), c 23·65(2) Å, β 116·3(5)°, Z = 8, conventional R on |F| being 0·058 for No 5092 independent ‘observed’ (I > 3s(I)) reflections. Sr(4-np)2.2(4-npH).8H2O, based on a subcell of the former, is monoclinic, P 21/c, a 15·576(5), b10·081(6), c 24·20(2) Å, β 117·99(5)° , Z = 4, R 0·054 for No 2908. Ba(4-np)2.2(4-npH).4H2O is orthorhombic, Fdd2, a 28·01(1), b 19·90(1), c 10·692(7)Å, Z = 8, R 0·028 for No 1967. The strontium array (and that of the calcium salt developed from it) may be represented as [(H2O)6Sr(4-npH.4-np)] (4-npH.4-np), a neutral ligand being unsymmetrically chelated to the strontium through the nitro group, with a quasi-parallel counter ion hydrogen-bonded to it by phenoxide confrontation. The other two 4-np residues make up a similar phenoxide-confronting pair (4-npH.4-np), the hydrogen being more intimately associated with one moiety. The barium salt is also an interesting array: the 10-coordinate barium lies on a crystallographic 2 axis, in an environment of two pairs of symmetry-related nitro-chelating ligand anions, and a pair of nitro-O coordinating neutral 4-npH ligands; the whole [(H2O)4Ba(4-np)2(4-npH)2] array may be envisaged as a single neutral (super)molecule. Hydrogen bonds between confronting phenoxides of the neutral 4-npH components of the parent and the 4-np- components of neighbouring molecules link the whole into a three-dimensional array.


2012 ◽  
Vol 68 (8) ◽  
pp. m209-m212 ◽  
Author(s):  
Jiang-Hong Fu ◽  
Yu-Ling Wang ◽  
Ying Chen ◽  
Chang-Hui Hu ◽  
Li Tang

The title compound, [CuNa(C4H3O7S)(C10H8N2)(H2O)3]n, consists of one CuIIcation, one NaIcation, one 2-sulfonatobutanedioate trianion (SSC3−), one 2,2′-bipyridyl (bpy) ligand and three coordinated water molecules as the building unit. The coordination of the CuIIcation is composed of two pyridyl N atoms, one water O atom and two carboxylate O atoms in a distorted square-pyramidal coordination geometry with an axial elongation. The NaIcation is six-coordinated by three water molecules and three carboxylate O atoms from three SSC3−ligands in a distorted octahedral geometry. Two SSC3−ligands link two CuIIcations to form a Cu2(SSC)2(bpy)2macrocyclic unit lying across an inversion centre, which is further linked by NaIcationsviaNa—O bonds to give a one-dimensional chain. Interchain hydrogen bonds link these chains to form a two-dimensional layer, which is further extended into a three-dimensional supramolecular framework through π–π stacking interactions. The thermal stability of the title compound has also been investigated.


Author(s):  
Jelena M. Andrić ◽  
Ivana M. Stanković ◽  
Snežana D. Zarić

The interactions of nucleic acid bases with non-coordinated and coordinated water molecules were studied by analyzing data in the Protein Data Bank (PDB) and by quantum chemical calculations. The analysis of the data in the crystal structures from the PDB indicates that hydrogen bonds involving oxygen or nitrogen atoms of nucleic acid bases and water molecules are shorter when water is bonded to a metal ion. These results are in agreement with the quantum chemical calculations on geometries and interaction energies of hydrogen bonds; the calculations on model systems show that hydrogen bonds of nucleic acid bases with water bonded to a metal ion are stronger than hydrogen bonds with non-coordinated water. These calculated values are similar to the strength of hydrogen bonds between nucleic acid bases. The results presented in this paper may be relevant to understand the role of water molecules and metal ions in the process of replication and stabilization of nucleic acids and also to understand the possible toxicity of metal ion interactions with nucleic acids.


1986 ◽  
Vol 41 (11) ◽  
pp. 1329-1332 ◽  
Author(s):  
Armin Weiss ◽  
Eugen Riegler ◽  
Christian Robl

Abstract The isotypic compounds (MC4O4·2 H2O)3·CH3COOH·H2O(M=Zn2+,Ni2+) crystallize in the cubic space group Pn3n. The 3-dimensional framework structure contains cavities, which may be filled with CH3COOH · H2O . The metal ions are coordinated almost octahedrally by two water molecules and four oxygen atoms of four C4O42- dianions. Thus the squarate dianions act as fourfold monodentate ligands. Strong hydrogen bonding between H2O and C4O42- has to be assumed.


2017 ◽  
Vol 73 (5) ◽  
pp. 424-429 ◽  
Author(s):  
Ya-Jie Kong ◽  
Peng Li ◽  
Li-Juan Han ◽  
Lu-Tong Fan ◽  
Peng-Peng Li ◽  
...  

Fluorine is the most electronegative element and can be used as an excellent hydrogen-bond acceptor. Fluorous coordination compounds exhibit several advantageous properties, such as enhanced high thermal and oxidative stability, low polarity, weak intermolecular interactions and a small surface tension compared to hydrocarbons. C—H...F—C interactions, although weak, play a significant role in regulating the arrangement of the organic molecules in the crystalline state and stabilizing the secondary structure. Two cadmium(II) fluorous coordination compounds formed from 2,2′-bipyridine, 4,4′-bipyridine and pentafluorobenzoate ligands, namely catena-poly[[aqua(2,2′-bipyridine-κ2 N,N′)(2,3,4,5,6-pentafluorobenzoato-κO)cadmium(II)]-μ-2,3,4,5,6-pentafluorobenzoato-κ2 O:O′], [Cd(C7F5O2)2(C10H8N2)(H2O)] n , (1), and catena-poly[[diaquabis(2,3,4,5,6-pentafluorobenzoato-κO)cadmium(II)]-μ-4,4′-bipyridine-κ2 N:N′], [Cd(C7F5O2)2(C10H8N2)(H2O)2] n , (2), have been synthesized solvothermally and structurally characterized. Compound (1) shows a one-dimensional chain structure composed of Cd—O coordination bonds and is stabilized by π–π stacking and O—H...O hydrogen-bond interactions. Compound (2) displays a one-dimensional linear chain structure formed by Cd—N coordination interactions involving the 4,4′-bipyridine ligand. Adjacent one-dimensional chains are extended into two-dimensional sheets by O—H...O hydrogen bonds between the coordinated water molecules and adjacent carboxylate groups. Moreover, the chains are further linked by C—H...F—C interactions to afford a three-dimensional network. In both structures, hydrogen bonding involving the coordinated water molecules is a primary driving force in the formation of the supramolecular structures.


2013 ◽  
Vol 69 (9) ◽  
pp. 1022-1025 ◽  
Author(s):  
Cui-Lian Guo ◽  
Xiao-Qiang Yao ◽  
Yong-Qiang Cheng ◽  
Yan Liu

In the title compound, [Ni(C12H6O4)(C22H16N2O)2(H2O)2]n, the Ni2+cation resides on a centre of inversion in a slightly distorted octahedral [N2O4] environment. The two carboxylate groups of each naphthalene-2,6-dicarboxylate (NDC2−) ligand, which reside on centres of inversion, link the NiIIcations into a one-dimensional chain. Identical chains are linked by intermolecular hydrogen bonds between coordinated water molecules and the uncoordinated N atoms of 4-{4-[4-(pyridin-4-yl)phenoxy]phenyl}pyridine ligands to form (4,4)-topological sheets, and then the different sheets are interlocked in an inclined fashion to give a three-dimensional polycatenation network. The stability of the structure is further enhanced by π–π stacking interactions between pyridine and benzene rings.


2007 ◽  
Vol 63 (11) ◽  
pp. m2652-m2653
Author(s):  
Zhi-Fang Jia ◽  
Jian-Fang Ma ◽  
Lai-Ping Zhang ◽  
Ting-Ting Han

In the title compound, [Cu2Cl4(C36H44N4O4)(H2O)2], the dinuclear complex molecule lies on an inversion centre. Each CuII atom shows a tetragonal–pyramidal coordination geometry formed by two Cl atoms, two N atoms from the macrocyclic ligand and one water molecule. The coordinated water molecules are hydrogen-bonded to the Cl atoms in adjacent molecules, generating a one-dimensional structure.


2011 ◽  
Vol 366 ◽  
pp. 169-172
Author(s):  
Li Hua Wang

Two new Eu (III) complexes with multifunctional ligands, 2, 2'-dithiosalicylic acid (L1) and 1-acetyl-2-naphthol-4, 4'-diaminodiphenyl ether (L2) have been prepared in ethanol solution. The complexes are stable in air. The infrared spectrum and luminescent spectra of Eu (III) complexes were studied. The results indicate that the oxygen atoms of the ligands (L1 and L2), the nitrogen atoms of L2, the oxygen atoms of the nitrate and coordinated water molecules coordinate to Eu (III) ions. The luminescent property of Eu (III) complexes have been investigated in solid state.


2009 ◽  
Vol 65 (6) ◽  
pp. m618-m618 ◽  
Author(s):  
Jian Yu

The CoIIion in the title complex, [Co(SO4)(C13H8N4)(H2O)2]n, has a slightly distorted octahedral coordination environment formed by two O atoms from two symmetry-related bridging sulfate ligands, two N atoms from a bis-chelating 1H-imidazo[4,5-f][1,10]phenanthroline (IPL) ligand and two O atoms from coordinated water molecules. The bridging sulfate ligands connect CoIIions to form a one-dimensional chain along theb-axis direction. In the crystal structure, intermolecular O—H...O, O—H...N and N—H...O hydrogen bonds link the chains into a three-dimensional network.


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