Search results for "complexes"
showing 10 items of 875 documents
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…
Synthesis and characterization of a Cu(II) complex of 2-benzylmercapto-5- methyl-1,3,4-thiadiazole (C10H10N2S 2)
2008
A Cu(II) complex of 2-benzylmercapto-5-methyl-1,3,4-thiadiazole was synthesized and characterized. The crystal structure of the copper complex and the free ligand were determined by single-crystal X-ray diffraction at room temperature: {[Cu(C10H10N2S2) 2(Cl)2], P1 triclinic, a = 8.1450(2) Å, b = 8.1690(2) Å, c = 10.8180(3) Å, α = 97.4040(12)°, β = 101.6270(11)°, γ = 116.1431(14)°; C10H10N2S2 ligand, Pbca orthorhombic, a = 8.7938(7) Å, b = 9.6491(7) Å, c = 25.3552(18) Å}. The metal complex framework consists of discrete units that provide crystalline stability through a network of van der Waals contacts. The Cu(II) is coordinated by two chloride ions and two 2-benzylmercapto-5-methyl-1,3,4- …
Charged Bis-Cyclometalated Iridium(III) Complexes with Carbene-Based Ancillary Ligands
2013
Charged cydometalated (CN) iridium(III) complexes with carbene-based ancillary ligands are a promising family of deep-blue phosphorescent compounds. Their emission properties are controlled primarily by the main CN ligands, in contrast to the classical design of charged complexes where NN ancillary ligands with low-energy pi* orbitals, such as 2,2'-bipyridine, are generally used for this purpose. Herein we report two series of charged iridium complexes with various carbene-based ancillary ligands. In the first series the CAN ligand is 2-phenylpyridine, whereas in the second one it is 2-(2,4-difluorophenyl)-pyridine. One biscarbene (:CC:) and four different pyridine carbene (NC:) chelators a…
A dinuclear rhodium(III) complex with the N,N′-ethylenebis(salicylideneiminato) (salen) ligand in a bridging bis-bidentate mode of coordination. Crys…
1990
In this communication we describe the synthesis and crystal structure of the complex [{Rh(η 2 -(C 6 H 4 )PPh 2 )(η 2 -P(o-ClC 6 H 4 )Ph 2 )} 2 (salen)]-(SbF 6 ) 2 , showing the bridging configuration of the salen ligand
Effects of preorganization in the chelation of UO22+ by hydroxamate ligands: cyclic PIPO– vs linear NMA–
2018
International audience; Many siderophores incorporate as bidentate chelating subunits linear and more seldomly cyclic hydroxamate groups. In this work, a comparative study of the uranyl binding properties in aqueous solution of two monohydroxamic acids, the prototypical linear N-methylacetohydroxamic acid (NMAH) and the cyclic analog 1-hydroxypiperidine-2-one (PIPOH), has been carried out. The complex [UO2(PIPO)(2)(H2O)] crystallized from slightly acidic water solutions (pH < 5), and its molecular structure was determined by X-ray diffraction. The uranyl speciation in the presence of both ligands has been thoroughly investigated in a 0.1 M KNO3 medium at 298.2 K by the combined use of four …
DNA binding, nuclease activity, DNA photocleavage and cytotoxic properties of Cu(II) complexes of N-substituted sulfonamides.
2013
Abstract Ternary copper(II) complexes [Cu(NST)2(phen)] (1) and [Cu(NST)2(NH3)2]·H2O (2) [HNST = N-(4,5-dimethylthiazol-2-yl)naphthalene-1-sulfonamide] were prepared and characterized by physico-chemical techniques. Both 1 and 2 were structurally characterized by X-ray crystallography. The crystal structures show the presence of a distorted square planar CuN4 geometry in which the deprotonated sulfonamide, acting as monodentate ligand, binds to the metal ion through the thiazole N atom. Both complexes present intermolecular π–π stacking interactions between phenanthroline rings (compound 1) and between naphthalene rings (compound 2). The interaction of the complexes with CT DNA was studied b…
New coordination polymer based on a triply bridged dicarboxylate ligand: Synthesis, structure, and magnetic properties of the adipato complex [Cu4(bp…
2007
International audience; One-pot reaction of copper(II) chloride dihydrate CuCl2 · 2H2O with 2,2′-bipyridyl (bpy = C10H8N2) in the presence of sodium adipate Na2adip (adip2− = [O2C(CH2)4CO2]2−) and potassium 1,1,3,3-tetracyano-2-ethoxypropenide (tcnoet− = [(NC)2CC(OEt)C(CN)2]−) gives the new compound [Cu4(bpy)4(adip)3](tcnoet)2 · 2H2O (1), which was characterized by single crystal X-ray diffraction analysis. The Cu(II) metal ion presents an elongated square pyramidal CuN2O3 environment, with an oxygen atom in apical position and a base plane involving almost equivalent bond lengths. The structure can be described as a pseudo dinuclear species in which two Cu(bpy) units are triply bridged by …
Polypyridyl-functionalizated alkynyl gold(i) metallaligands supported by tri- and tetradentate phosphanes
2017
A series of alkynyl gold(I) tri and tetratopic metallaligands of the type [Au3(CuC-R)3(μ3-triphosphane)] (R = 2,2'-bipyridin-5-yl or C10H7N2, 2,2':6',2''-terpyridin-4-yl or C15H10N3; triphosphane = 1,1,1-tris(diphenylphosphanyl) ethane or triphos, 1,3,5-tris(diphenylphosphanyl)benzene or triphosph) and [Au4(CuC-R)4 (μ4-tetraphosphane)] (R = C10H7N2, C15H10N3; tetraphosphane = tetrakis(diphenylphosphanylmethyl)methane or tetraphos, 1,2,3,5-tetrakis(diphenylphosphanyl)benzene or tpbz, tetrakis(diphenylphosphaneylmethyl)-1,2- ethylenediamine or dppeda) were obtained in moderate to good yields. All complexes could be prepared by a Q4 reaction between the alkynyl gold(I) polymeric species [Au(Cu…
Designing dicyanamide bridged 1D molecular architecture from a mononuclear copper(II) Schiff base precursor: Syntheses, structural variations and mag…
2009
International audience; A new tridentate N2O donor Schiff base ligand [(C6H5C(OH)CHC(CH3)NCH2C5H4N)LH] was obtained by 1:1 condensation of benzoylacetone with 2-picolylamine and has been used to synthesise a mononuclear [CuLCl] (1) and an end-to-end dicyanamide bridged polynuclear {[Cu2(μ-L)2(μ2-1,5-(CN)2N)]ClO4}n (2) copper(II) complexes. The ligand, 1 and 2 were clearly characterised by elemental analysis, FT-IR, 1H NMR, UV–Vis spectral studies, electrochemical studies and in addition single crystal X-ray diffraction studies were performed for 1 and 2. The Schiff base ligand [LH] shows a significant variation in its coordination behaviour with copper(II) ion in absence and in presence of …
Multiple Roles of Isocyanides in Palladium-Catalyzed Imidoylative Couplings: A Mechanistic Study
2016
International audience; Kinetic, spectroscopic and computational studies examining a palladium-catalyzed imidoylative coupling highlight the dual role of isocyanides as both substrates and ligands for this class of transformations. The synthesis of secondary amides from aryl halides and water is presented as a case study. The kinetics of the oxidative addition of ArI with RNC-ligated Pd-0 species have been studied and the resulting imidoyl complex [(ArC=NR)Pd(CNR)(2)I] (Ar=4-F-C6H4, R = tBu) has been isolated and characterized by X-ray diffraction. The unprecedented ability of this RNC-ligated imidoyl-Pd complex to undergo reductive elimination at room temperature to give the amide in the p…