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Coordinated Water Molecules (coordinated + water_molecule)
Selected AbstractsAnion-Directed Template Synthesis and Hydrolysis of Mono-Condensed Schiff Base of 1,3-Pentanediamine and o -Hydroxyacetophenone in NiII and CuII ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2008Pampa Mukherjee Abstract Bis(o -hydroxyacetophenone)nickel(II) dihydrate, on reaction with 1,3-pentanediamine, yields a bis-chelate complex [NiL2]·2H2O (1) of mono-condensed tridentate Schiff baseligand HL {2-[1-(3-aminopentylimino)ethyl]phenol}. The Schiff base has been freed from the complex by precipitating the NiII as a dimethylglyoximato complex. HL reacts smoothly with Ni(SCN)2·4H2O furnishing the complex [NiL(NCS)] (2) and with CuCl2·2H2O in the presence of NaN3 or NH4SCN producing [CuL(N3)]2 (3) or [CuL(NCS)] (4). On the other hand, upon reaction with Cu(ClO4)2·6H2O and Cu(NO3)2·3H2O, the Schiff base undergoes hydrolysis to yield ternary complexes [Cu(hap)(pn)(H2O)]ClO4 (5) and [Cu(hap)(pn)(H2O)]NO3 (6), respectively (Hhap = o -hydroxyacetophenone and pn = 1,3-pentanediamine). The ligand HL undergoes hydrolysis also on reaction with Ni(ClO4)2·6H2O or Ni(NO3)2·6H2O to yield [Ni(hap)2] (7). The structures of the complexes 2, 3, 5, 6, and 7 have been confirmed by single-crystal X-ray analysis. In complex 2, NiII possesses square-planar geometry, being coordinated by the tridentate mono-negative Schiff base, L and the isothiocyanate group. The coordination environment around CuII in complex 3 is very similar to that in complex 2 but here two units are joined together by end-on, axial-equatorial azide bridges to result in a dimer in which the geometry around CuII is square pyramidal. In both 5 and 6, the CuII atoms display the square-pyramidal environment; the equatorial sites being coordinated by the two amine groups of 1,3-pentanediamine and two oxygen atoms of o -hydroxyacetophenone. The axial site is coordinated by a water molecule. Complex 7 is a square-planar complex with the Ni atom bonded to four oxygen atoms from two hap moieties. The mononuclear units of 2 and dinuclear units of 3 are linked by strong hydrogen bonds to form a one-dimensional network. The mononuclear units of 5 and 6 are joined together to form a dimer by very strong hydrogen bonds through the coordinated water molecule. These dimers are further involved in hydrogen bonding with the respective counteranions to form 2-D net-like open frameworks. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Two isomorphous cobalt(II) complexes: poly[[diaqua-,-2,5-dicarboxybenzene-1,4-dicarboxylato-,-1,2-di-4-pyridylethene-cobalt(II)] 1,2-di-4-pyridylethene solvate] and the 1,2-di-4-pyridylethane analogueACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2009Ana María Atria The two isomorphous title structures, formulated as {[Co(C10H4O8)(C12H10N2)(H2O)2]·C12H10N2}n, (I), and {[Co(C10H4O8)(C12H12N2)(H2O)2]·C12H12N2}n, (II), respectively, are reported. They crystallize in the space group P with only one formula unit in the asymmetric unit, so that the organic ligands lie about inversion centres and the Co atom lies on an inversion centre. The Co atoms are octahedrally coordinated by a carboxylate O atom from 2,5-dicarboxybenzene-1,4-dicarboxylate (H2btc), one N atom from 1,2-di-4-pyridylethene (L) in (I) or from 1,2-di-4-pyridylethane (L) in (II), and one coordinated water molecule, plus their inversion-related species. This particular coordination results in a two-dimensional array, with an elemental unit in the shape of a parallelogram having the CoII cations at the corners, linked in one direction by L bridges and in the opposite direction by H2btc groups. The L solvent molecules act as pillars between parallel planes, linking them by strong hydrogen bonds where the H atoms lie midway between the formal donor/acceptor atoms in a `shared' mode. Comparison is made with structures presenting the same structural motif, strongly suggesting that the two-dimensional arrangement reported here might be a very stable robust building block for molecular engineering purposes. [source] The new three-dimensional supramolecule bis{,-2-[(4-hydroxybenzoyl)hydrazonomethyl]phenolato}bis[aquacopper(II)] dinitrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2008Hua Yin In the title centrosymmetric binuclear complex, [Cu2(C14H11N2O3)2(H2O)2](NO3)2, the two metal centres are bridged by the phenolate O atoms of the ligand, forming a Cu2O2 quadrangle. Each Cu atom has a distorted square-pyramidal geometry, with the basal donor atoms coming from the O,N,O,-tridentate ligand and a symmetry-related phenolate O atom. The more weakly bound apical donor O atom is supplied by a coordinated water molecule. When a further weak Cu...O interaction with the 4-hydroxy O atom of a neighbouring cation is considered, the extended coordination sphere of the Cu atom can be described as distorted octahedral. This interaction leads to two-dimensional layers, which extend parallel to the (100) direction. The two-dimensional polymeric structure contrasts with other reported structures involving salicylaldehyde benzoylhydrazone ligands, which are usually discrete mono- or dinuclear Cu complexes. The nitrate anions are involved in a three-dimensional hydrogen-bonding network, featuring intermolecular N,H...O and O,H...O hydrogen bonds. [source] Lanthanide(III) Complexes of 4,10-Bis(phosphonomethyl)-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (trans -H6do2a2p) in Solution and in the Solid State: Structural Studies Along the SeriesCHEMISTRY - A EUROPEAN JOURNAL, Issue 28 2010M. Paula Abstract Complexes of 4,10-bis(phosphonomethyl)-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (trans -H6do2a2p, H6L) with transition metal and lanthanide(III) ions were investigated. The stability constant values of the divalent and trivalent metal-ion complexes are between the corresponding values of H4dota and H8dotp complexes, as a consequence of the ligand basicity. The solid-state structures of the ligand and of nine lanthanide(III) complexes were determined by X-ray diffraction. All the complexes are present as twisted-square-antiprismatic isomers and their structures can be divided into two series. The first one involves nona-coordinated complexes of the large lanthanide(III) ions (Ce, Nd, Sm) with a coordinated water molecule. In the series of Sm, Eu, Tb, Dy, Er, Yb, the complexes are octa-coordinated only by the ligand donor atoms and their coordination cages are more irregular. The formation kinetics and the acid-assisted dissociation of several LnIII,H6L complexes were investigated at different temperatures and compared with analogous data for complexes of other dota-like ligands. The [Ce(L)(H2O)]3, complex is the most kinetically inert among complexes of the investigated lanthanide(III) ions (Ce, Eu, Gd, Yb). Among mixed phosphonate,acetate dota analogues, kinetic inertness of the cerium(III) complexes is increased with a higher number of phosphonate arms in the ligand, whereas the opposite is true for europium(III) complexes. According to the 1H,NMR spectroscopic pseudo-contact shifts for the Ce,Eu and Tb,Yb series, the solution structures of the complexes reflect the structures of the [Ce(HL)(H2O)]2, and [Yb(HL)]2, anions, respectively, found in the solid state. However, these solution NMR spectroscopic studies showed that there is no unambiguous relation between 31P/1H lanthanide-induced shift (LIS) values and coordination of water in the complexes; the values rather express a relative position of the central ions between the N4 and O4 planes. [source] Fluorinated ,-Diketones for the Extraction of Lanthanide Ions: Photophysical Properties and Hydration Numbers of Their EuIII ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2006Anne-Sophie Chauvin Abstract Tris(,-diketonato)europium(III) with a series of variably fluorinated ligands derived from 3,5-heptanedione were synthesised with the aim of determining their hydration state under extraction conditions. The number of coordinated water molecules was determined by measuring the lifetime of the Eu(5D0) excited level in water and deuterated water. The hydration gain (,q = q , q0) after shaking chloroform solutions during 10 min with 0.1 M NaClO4 aqueous solutions depends on the fluorination extent of the diketonates: fluorination of one methyl group leads to a decrease in ,q of ca. 0.5 unit, while fluorination of one ethyl group results in a decrease of ca. 1.3 units. Highly fluorinated complexes (i.e with hexafluoroacetylacetonate and related ligands) display a hydration number close to one while poorly fluorinated compounds (or nonfluorinated ones, such as the acetylacetonate complex) have a hydration state close to two. Photophysical properties of the EuIII ,-diketonates are also described and the synthesis of the fluorinated ,-diketones is re-investigated and discussed in details. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] New Insights on Near-Infrared Emitters Based on Er-quinolinolate Complexes: Synthesis, Characterization, Structural, and Photophysical Properties,ADVANCED FUNCTIONAL MATERIALS, Issue 14 2007F. Artizzu Abstract Erbium quinolinolates, commonly assumed to be mononuclear species with octahedral co-ordination geometry, have been proposed as promising materials for photonic devices but difficulties in obtaining well defined products have so far limited their use. We report here the conditions to obtain in high yields three different kinds of pure neutral erbium quinolinolates by mixing an erbium salt with 8-quinolinol (HQ) and 5,7-dihalo-8-quinolinol (H5,7XQ: X,=,Cl and Br): i),the trinuclear complex Er3Q9 (1) which is obtained with HQ deprotonated by NH3 in water or ethanol/water mixtures; ii),the already known dimeric complexes based on the unit [Er(5,7XQ)3(H2O)2] [X,=,Cl (2) and Br (3)]; iii) the mononuclear [Er(5,7XQ)2(H5,7XQ)2Cl] [X,=,Cl (4) and Br (5)] complexes, obtained in organic solvents without base addition, where the ion results coordinated to four ligands, two deprotonated chelating, and two as zwitterionic monodentate oxygen donors. These results represent a further progress with respect to a recent reinvestigation on this reaction, which has shown that obtaining pure and anhydrous octahedral ErQ3, the expected reaction product, is virtually impossible, but failed in the isolation of 1 and of the neutral tetrakis species based on H5,7XQ ligands. Structural data provide a detailed description of the molecules and of their packing which involves short contacts between quinoxaline ligands, due to ,,, interactions. Electronic and vibrational studies allow to select the fingerprints to distinguish the different products and to identify the presence of water. The structure/property relationship furnishes a satisfactory interpretation of the photo-physical properties. Experimental evidence confirms that the most important quenchers for the erbium emission are the coordinated water molecules and shows that the ligand emission is significantly affected by the ,,, interactions. [source] Vibrational spectroscopic and force field studies of copper(II) chloride and bromide compounds, and crystal structure of KCuBr3JOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2008Liubov V. Stepakova Abstract Vibrational spectroscopic and force field studies have been performed of 15 related copper(II) chloride and copper(II) bromide compounds, including hydrated salts crystallizing in ternary aqueous systems with alkali and ammonium halides. For halocuprates with distorted octahedral coordination characteristic stretching Raman wavenumbers, corresponding to symmetric stretching CuIIX modes in the equatorial plane, were found in the ranges 247,288 cm,1 for X = Cl, and 173,189 cm,1 for X = Br, while the low-wavenumber stretching modes for the weaker axial CuX interactions varied considerably. The tetrahedral coordination for Cs2CuCl4 and Cs2CuBr4 leads to somewhat lower CuX symmetric stretching wavenumbers, 295 and 173 cm,1, respectively. The assignments of the copper,ligand stretching vibrations were performed with the aid of normal coordinate calculations. Correlations between force constants, averaged CuX stretching wavenumbers and bond distances have been evaluated considering the following aspects: (1) Jahn,Teller tetragonal distortion (axial elongation) of the octahedral copper(II) coordination environment, (2) differences between terminal and bridging halide ligands (3) effects of coordinated water and the influence of outer-sphere cations. Force constant ratios for terminal and bridging metal,halide bonds reveal characteristic differences between planar and tetrahedrally coordinated M2X6 species. In the hydrated copper(II) halide complexes, the halide ligands are more strongly bound than coordinated water molecules. The crystal structure of KCuBr3 (K2Cu2Br6), which was determined to provide structural information for the force field analyses, contains stacks of planar dimeric [Cu2Br6]2, complexes held together by weak axial CuBr interactions. Copyright © 2007 John Wiley & Sons, Ltd. [source] Poly[[tetraaqua(,7 -pyridine-2,3,5,6-tetracarboxylato)dicadmium(II)] monohydrate]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2010Sitang Yan The title compound, {[Cd2(C9HNO8)(H2O)4]·H2O}n, consists of two crystallographically independent CdII cations, one tetrabasic pyridine-2,3,5,6-tetracarboxylate (pdtc) anion, four coordinated water molecules and one solvent water molecule. The CdII cations have distorted square-antiprismatic (one pyridine N, six carboxylate O and one water O atom) and octahedral (three carboxylate O and three water O atoms) coordination environments. Each pdtc ligand employs its pyridine and carboxylate groups to chelate and bridge seven CdII cations. The square-antiprismatic coordinated CdII cations are linked by pdtc ligands into a lamellar framework structure, while the octahedral coordinated CdII cations are bridged by the ,2 -carboxylate O atoms and the pdtc ligands into a chain network that further joins neighbouring lamellae into a three-dimensional porous network. The cavities are filled with solvent water molecules that are linked to the host through complex hydrogen bonding. [source] Triaqua(,-7-iodo-8-oxidoquinoline-5-sulfonato-,2N,O8)dioxidouranium(VI) dihydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010Pandian Sasikumar In the title compound, [U(C9H4INO4S)O2(H2O)3]·2H2O, the asymmetric unit contains a UO22+ ion coordinated by the N and O atoms of a 7-iodo-8-oxidoquinoline-5-sulfonate dianion (ferron anion) and three coordinated water molecules, and two uncoordinated water molecules. The UO22+ ion exhibits a seven-coordinate pentagonal bipyramidal geometry. The usual sulfonate oxygen coordination is absent but the sulfonate O atoms, along with the coordinated and lattice water molecules, play a vital role in assembling the three-dimensional structure via an extensive network of intermolecular O,H...O hydrogen bonds and ,,, stacking interactions. [source] catena -Poly[[[tetraaquazinc(II)]-,-4-amino-3,5-di-3-pyridyl-4H -1,2,4-triazole] sulfate monohydrate] and poly[[bis(,-4-amino-3,5-di-4-pyridyl-4H -1,2,4-triazole)diaquacopper(II)] dinitrate octahydrate]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009Hai-Ying Wang The isomeric bent triazole-containing ligands 4-amino-3,5-di-3-pyridyl-4H -1,2,4-triazole (L1) and 4-amino-3,5-di-4-pyridyl-4H -1,2,4-triazole (L2) have been used to create the two novel title complexes catena -poly[[[tetraaquazinc(II)]-,-4-amino-3,5-di-3-pyridyl-4H -1,2,4-triazole] sulfate monohydrate], {[Zn(C12H10N6)(H2O)4]SO4·H2O}n, (I), and poly[[diaquabis(,-4-amino-3,5-di-4-pyridyl-4H -1,2,4-triazole)copper(II)] dinitrate octahydrate], {[Cu(C12H10N6)2(H2O)2](NO3)2·8H2O}n, (II). The ZnII and CuII atoms are all six-coordinated in approximately octahedral environments. Compound (I) presents a sinusoidal chain generated by ZnO4 cores which are bridged by L1 ligands in a cisoid conformation. These sinusoidal chains are bound to each other by O,H...O hydrogen bonds between coordinated water molecules of neighboring chains into a two-dimensional network. These layers stack in an ,ABAB, sequence and are further linked into a three-dimensional framework through O,H...N hydrogen bonds between coordinated water molecules and the N atoms of the triazole rings. In (II), the CuII centers are bridged by the L2 ligands to form a two-dimensional network with square grids. All of the two-dimensional nets also stack alternately along the crystallographic a axis. Neighboring layers are further linked into a three-dimensional framework via interlayer N,H...N hydrogen bonds between ,NH2 groups of the triazole rings and the N atoms in the triazole rings. [source] Diaquadichloridobis(1H -imidazole)manganese(II) at 100 KACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009Barbara Hachu The mononuclear title complex, [MnCl2(C3H4N2)2(H2O)2], is located on a crystallographic inversion center. The MnII ion is coordinated by two imidazole ligands [Mn,N = 2.2080,(9),Å], two Cl atoms [Mn,Cl = 2.5747,(3),Å] and two water molecules [Mn,O = 2.2064,(8),Å]. These six monodentate ligands define an octahedron with almost ideal angles: the adjacent N,Mn,O, N,Mn,Cl and O,Mn,Cl angles are 90.56,(3), 92.04,(2) and 90.21,(2)°, respectively. Hydrogen bonds between the coordinated water molecules and Cl atoms form a two-dimensional network parallel to (100) involving R42(8) rings. The two-dimensional networks link into a three-dimensional framework through weaker N,H...Cl interactions. Thermogravimetric analysis results are in accordance with the water-coordinated character of the substance and its dehydration in two successive steps. [source] Tetraaquabis(d -camphor-10-sulfonato)calcium(II)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2009Dejan Jeremi The structure of the title compound, [Ca(C10H15O4S)2(H2O)4], is the first example in which two d -camphor-10-sulfonate anions are coordinated to a metal ion, in this case with direct Ca,O bonding. The molecule has crystallographically imposed twofold symmetry with the Ca atom on the twofold axis. Hydrogen bonds are formed between the coordinated water molecules and the O atoms of the SO3, groups of adjacent molecules, leading to the formation of a two-dimensional layered network. The compound displays sharp wavelength-selective transparency in the UV,visible spectrum, offering the potential for application as an optical filter. [source] Tetraaquabis(2-methoxybenzaldehyde isonicotinoylhydrazone)cadmium(II) dinitrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2007Zhongwu Fu The CdII centre in the title complex, [Cd(C14H13N3O2)2(H2O)4](NO3)2, occupies a crystallographic inversion centre and is coordinated by two donor N atoms from two 2-methoxybenzldehyde isonicotinoylhydrazone ligands and by four O atoms from four coordinated water molecules, giving a slightly distorted octahedral geometry. There is an extended three-dimensional network structure resulting from O,H...O hydrogen bonds between coordinated water and nitrate anions, and between coordinated water and carbonyl O atoms, and from N,H...O hydrogen bonds between NH groups and nitrate O atoms. [source] Poly[[hexaaquabis[,4 -2-hydroxy-5-(4-sulfonatophenyldiazenyl)benzoato]dibarium(II)] 4,4,-bipyridine solvate]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2007Hong Liu The title compound, {[Ba2(C13H8N2O6S)2(H2O)6]·C10H8N2}n, possesses a novel two-dimensional porous coordination network, in which each BaII ion is nine-coordinated by three carboxylate O atoms, two sulfonate O atoms and four water molecules in an irregular coordination environment. Hydrogen-bond interactions between coordinated water molecules and sulfonate/hydroxyl groups hold the network layers together and produce a three-dimensional supramolecular architecture. [source] Synthesis, Properties and Crystal Structure of Seven-coordinated Organotin Complex [nBu2Sn(OOCC5H4N-2)2(H2O)]CHINESE JOURNAL OF CHEMISTRY, Issue 12 2002Han-Dong Yin Abstract A novel seven-coordinated organotin complex [nBu2Sn-(OOCC5H4N-2)2(H2O)] was unexpectedly synthesized by reaction of nBu3SnCl with 2-pyridinecarboxylic acid in 1:1 molar ratio in the presence of organic base Et3N. The crystal structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to rhombohedral with space group R-3c, a = 1.5807(3) nm, b = 1.5807(3) nm, c = 1.5807(3) nm, , = 105.717(2)°, , = 105.717(2)°, , = 105.717(2)°, Z = 6, V = 3.397(8) nm3, Dc = 1.452 g/cm3, , = 1.158 mm,1, F(000) = 1512, R1 = 0.0447, wR2 = 0.1038. In crystal, the tin atoms rendered seven-coordinate in a distorted pentagonal bipyramidal geometry. The two-dimensional network structure was formed by H-bonding interaction between the free oxygen atoms of carboxyl groups and the coordinated water molecules. [source] | ||||||||||