Search results for "Denticity"
showing 10 items of 376 documents
Cyanido‐Bearing Cobalt(II/III) Metalloligands – Synthesis, Crystal Structure, and Magnetic Properties
2014
New examples of cyanido-bearing cobalt(III/II) complexes have been obtained by treatment of CoCl2·6H2O with bidentate nitrogen donors and potassium cyanide in a methanol/water mixture. Depending on the chelating ligand, the cobalt(III) complexes PPh4[Co(en)(CN)4] (1, en = ethylenediamine), PPh4[Co(ampy)(CN)4]·1.5H2O [2, ampy = 2-(aminomethyl)pyridine], and PPh4[Co(phen)(CN)4]·CH3OH·0.25H2O (3, phen = 1,10-phenanthroline) and the cobalt(II) complex PPh4[Co(dmphen)(CN)3]·3H2O (4, dmphen = 2,9-dimethyl-1,10-phenanthroline) were obtained. The complexes were characterized by single-crystal X-ray diffraction and variable-temperature magnetic measurements. They are all mononuclear species with six…
Acetazolamide-M(II) [M(II) = Co(II), Ni(II), Cu(II)] complexes with ethylamine, diethylamine, triethylamine, and potassium hidroxide
1991
Abstract Complexes of Co(II), Ni(II), and Cu(II) with dideprotonated Acm are synthesized and characterized. Acm acts as bidentate ligand through the N-sulfonamido atom and the N-thiadiazole atom except for K6CoAcm4·6H2O in which Acm behaves as monodentate through the N-sulfonamido atom.
Exploiting 1,4-naphthoquinone and 3-iodo-1,4-naphthoquinone motifs as anion binding sites by hydrogen or halogen-bonding interactions
2019
We describe here the utilization of 1,4-naphthoquinone and 3-iodo-1,4-naphthoquinone motifs as new anion binding sites by hydrogen- or halogen-bonding interactions, respectively. These binding sites have been integrated in bidentate ester based receptors. Emission experiments reveal that both receptors selectively recognize sulfate anions, which induced a remarkable increase of a new emission band attributed to the formation of π-stacking interactions between two 1,4-naphthoquinone units. Absorption spectroscopy and mass spectrometry indicate the disruption of the ester group of the 1,4-naphthoquinone based receptor in the presence of HP2O73−, H2PO4−, F−, AcO− and C6H5CO2− and in the haloge…
Bis and tris(oxalato)ferrate(iii) complexes as precursors of polynuclear compounds
2005
The preparation and crystal structure of two oxalato-bridged NaI–FeIII compounds, [Na3Fe(ox)3(H2O)4]·H2O (1) and [FeII(phen)3][NaFe(ox)3(H2O)3]·4H2O (5), two mononuclear FeIII complexes AsPh4[Fe(bipy)(ox)2]·H2O (3) and AsPh4[Fe(phen)(ox)2]·H2O (4) and an oxalato-bridged FeIII compound [AsPh4]4[Fe2(ox)5]·5H2O (2) (ox = oxalate dianion, bipy = 2,2′-bipyridine, phen = 1,10-phenantroline and AsPh4+ = tetraphenylarsonium cation) are reported here. The structure of 1 consists of infinite anionic [NaFe(ox)3]2− layers linked trough centrosymmetric [Na4(H2O)8]4+ tetranuclear units yielding a three-dimensional motif. Crystallization water molecules ensure the cohesion of the crystal lattice in 1. The…
Copper(II)-methylmalonate complexes with unidentate N-donor ligands: Syntheses, structural characterization and magnetic properties
2009
Abstract Two new methylmalonate-bridged copper(II) complexes with the formulas [Cu(3-Ipy)(Memal)(H 2 O)] ( 1 ) and [Cu(2,4′-bpy)(Memal)(H 2 O)] · 3H 2 O ( 2 ) [Memal = methylmalonate dianion, 3-Ipy = 3-iodopyridine, 2,4′-bpy = 2,4′-bipyridine] have been synthesized and characterized by X-ray diffraction. Both compounds crystallize in the monoclinic space group P 2 1 / n and Z = 4, with unit cell parameters a = 8.5874(13) A, b = 7.1738(14) A, c = 19.093(5) A, β = 99.509(15)° in 1 and a = 17.375(4) A, b = 7.3305(14) A, c = 14.247(3) A, β = 111.409(15)° in 2 . The structures of 1 and 2 consist of zigzag chains of anti-syn carboxylate-bridged copper(II) ions running along the b directi…
Structural, vibrational, thermal and magnetic investigation of novel Co(II), Cu(II), Zn(II) and Hg(II) crystalline metal complexes with 2-amino-5-ben…
2005
Abstract The 2-amino-5-benzylmercapto-1,3,4-thiadiazole (C9H9N3S2) is a low weight model of a protonated copolymer resin used as a metal uptake agent. New monomeric crystalline metal complexes of C9H9N3S2 with Co(II), Cu(II), Zn(II) and Hg(II) were synthesized and investigated in order to facilitate the interpretation of the metal/resin binding mode. These materials have been studied by single crystal X-ray Diffraction and FTIR Spectroscopy at room temperature. Crystal data for these triclinic phases are reported. All frameworks consist of discrete monomeric units that provide crystalline stability through a network of hydrogen bond interactions. The Co(II), Zn(II) and Hg(II) ions are surro…
catena-Poly[[bis(3-pyridylmethanol-κN)copper(II)]-μ-oxalato-1κ2 O 1,O 2:2κ2 O 1′,O 2′]
2007
In the title compound, [Cu(C2O4)(C6H7NO)2] n , the CuII atom is six-coordinated in a slightly deformed elongated octahedral arrangement and the 3-(hydroxymethyl)pyridine ligand, surprisingly, acts as a monodentate ligand coordinated only through the N atom of the pyridine ring. The oxalate ligands, on inversion centres, bridge the metal ions, forming infinite chains. The chains are linked by intermolecular O—H...O hydrogen bonds into a three-dimensional network.
Synthesis, properties and crystal structure of bis(metiamide)bis(isothiocyanato)nickel(II)
1991
Abstract The crystal structure of Ni(metiamide)2(NCS)2 was determined by X-ray diffraction methods. Unlike cimetidine, which is a tridentate ligand, metiamide (C9H16N4S2): N-Methyl-N-[2-{(5-methylimidazol-4-yl)methylthio}ethyl]thiourea (which also possesses three potential donor sites) is bidentate, coordinated to the nickel atom through N(imidazole) and S(thioether) atoms. The S(thiourea) atom does not take part in the coordination; instead, the isothiocyanate ion is coordinated through nitrogen to the metal atom. The nickel atom lies on a centre of symmetry in an elongated octahedral environment: the nitrogen atoms occupy equatorial positions (NiN = 2.04 and 2.06 A) and S(thioether) atom…
Mössbauer studies on tin(IV) and organotin(IV) diacetylbis(benzoylhydrazone) complexes
1974
Abstract The Mossbauer parameters of Ph 2 SnDB, PhClSnDB and Sn(DB) 2 were determined, where DB 2− is the dianion of the multidentate ligand diacetylbis(benzoylhydrazone). According also to data treatment with the point charge model formalism, the configurations of Ph 2 Sn IV and PhSn IV derivatives appear to be essentially octahedral, with linear CSnC and CSnCl skeletons. As to Sn(DB) 2 , it appears that the electrical charge density at the Sn IV nucleus has a cubic symmetry, which is consistent with both tetrahedral and octahedral configurations around Sn IV .
Synthesis, spectroscopic, and X-ray structural study of aqua-bis(thymine-N 1 ,N 4 )-ethylenediamine copper(II)dihydrate [Cu(Thy) 2 (en)(H 2 O)].2H 2 O
2016
International audience; A new compound of thyminato anions and ethylenediamine with five-coordinate Cu(II) is synthesized. Elemental analysis and spectroscopic techniques (IR, UV-visible) were used to characterize this compound and its crystal structure was determined by single-crystal X-ray diffraction. The crystal structure consists of the neutral mononuclear complex [Cu(Thy)(2)(en)(H2O)]center dot 2H(2)O. The environment around Cu(II) ion exhibits a square pyramidal geometry with two nitrogen atoms of ethylenediamine and two other nitrogen atoms of the monodentate monoanions of thymine building the equatorial plane. The oxygen atom from H2O molecule occupies the apical position. The comp…