Search results for "square"
showing 10 items of 1317 documents
New Cu(II) and Zn(II) complexes of benzolamide with diethylenetriamine: synthesis, spectroscopy and X-ray structures
2000
Abstract New benzolamide (H2bz, 5-phenylsulfonamide-1,3,4-thiadiazole-2-sulfonamide) zinc(II) and copper(II) complexes with diethylenetriamine were synthesized and characterized. The crystal structures of the [M(Hbz)2(dien)] (M=Cu(II), Zn(II); dien=diethylenetriamine) complexes were determined. The metal centre adopts a near regular square pyramidal geometry. The benzolamidate anion acts as a monodentate ligand through the thiadiazole N atom contiguous to the deprotonated sulfonamido group. Spectroscopic properties are in good agreement with the crystal structures. The EPR and electronic spectroscopic studies showed that the copper(II) species doped into the zinc(II) complex adopts a near s…
Structure, spectroscopic and magnetic properties of a novel 1-D coordination copper(II) polymer containing BIMAM ligand [BIMAM=bis(imidazol-2-yl)meth…
2006
Abstract This paper reports the synthesis and complete characterization (structural, spectroscopic and magnetic) of [Cu(HBIMAM)Cl(C4O4)]n · (H2O)n [BIMAM = bis(imidazol-2-yl)methylaminomethane]. This compound is made of infinite chains – running along c axis – built from [CuCl(HBIMAM)]+ units bridged together by μ-O1,O3-bis(monodentate) squarate anions. Non-covalent interactions (H-bonds and π–π) drive the build-up of an infinite three-dimensional array. The coordination polyhedron about the copper(II) ion is distorted square pyramidal. The EPR spectrum is indicative of a d z 2 - y 2 ground state for the Cu(II) ions with significant contribution of d z 2 . Magnetic susceptibility measuremen…
Three one-dimensional systems with end-to-end dicyanamide bridges between copper(ii) centres: structural and magnetic properties
2002
The preparation, crystal structures and magnetic properties of three different copper(II) chains of formula [Cu(pyim)(H2O)(dca)]n(NO3)n (1), [Cu(dpa)(dca)2]n (2) and [Cu(bpa)(dca)2]n (3) [pyim = 2-(2-pyridyl)imidazole, dca = dicyanamide anion, dpa = 2,2′-dipyridylamine and bpa = 1,2-bis(4-pyridyl)ethane] are reported. A chain structure with single, symmetrical, end-to-end dca bridges is found in compound 1. This bridging mode, with two short, equatorially coordinated Cu–N bonds has not been previously observed in the [Cu(dca)Xn] (X = coligand) family of compounds. The copper atom in 1 has a distorted square pyramidal geometry with a bidentate pyim ligand and two nitrile nitrogen atoms from …
Preparation, crystal structure and magnetic properties of di-2-pyridylamine (dpa) copper(II) complexes [Cu(dpa)(N3)2]n and [Cu2(dpa)2(NCO)4]
2008
Abstract The preparation, crystal structures and magnetic properties of two copper(II) complexes with di-2-pyridylamine (dpa) as end-cap ligand and azide (1) and cyanate (2) as bridging groups, [Cu(dpa)(N3)2]n (1) and [Cu2(dpa)2(NCO)4] (2), are reported. Compound 1 consists of uniform chains of copper(II) ions bridged by single μ-1,1-azido groups whereas that of compound 2 is made up of centrosymmetric dicopper(II) units with double μ-1,1-N-cyanate bridges, the other two cyanate groups acting as terminal ligands. The copper atoms in 1 and 2 are five-coordinated with two nitrogen atoms of a bidentate dpa ligand (1 and 2), one nitrogen atom from a terminally bound azide (1)/cyanate (2) and tw…
Synthesis, X‐ray Crystal Structure and Magnetic Properties of Oxalato‐Bridged Copper( II ) Complexes with 2,3‐Bis(2‐pyridyl)pyrazine, 2,3‐Bis(2‐pyrid…
2004
Five oxalate-containing copper(II) complexes of formula [Cu(dpq)(H2O)(ox)]·5H2O (1), [Cu(dpp)(H2O)(ox)]·H2O (2), [Cu(bpz)(ox)]n (3), [Cu2(dpp)2(H2O)2(NO3)2(ox)]·4H2O (4) and [Cu2Cl2(bpz)2(H2O)2(ox)][Cu(bpz)(H2O)2(ox)]·2H2O (5) [dpq = 2,3-bis(2-pyridyl)quinoxaline; dpp = 2,3-bis(2-pyridyl)pyrazine; bpz = 2,2′-bipyrazine; ox = oxalate] were prepared and their structures were determined by X-ray diffraction on single crystals. Complexes 1 and 2 are discrete mononuclear complexes with oxalate and dpq (1)/dpp (2) acting as bidentate ligands. Complex 3 is a neutral oxalato-bridged (2,2′-bipyrazine)copper(II) chain where the oxalate adopts a bidentate/monodentate coordination mode, whereas 4 is an…
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 …
Electronic properties and crystal structure of aqua (mepirizole-oxalato)copper(II)monohydrate: [Cu(C11H14N4O2)C2O4·H2O]H2O
1988
Abstract A Cu(ll) complex with mepirizole: 4-methoxy-2-(5-methoxy-3-methyl-pyrazoll-yl)-6-methylpyrimidine (L) and oxalate as ligands with the formula [CuL(C2O4)(H2O)]·H2O has been synthesized. The crystal structure has been determined by X-ray diffraction analysis: monoclinic, space group P21/n, Z = 4, a = 7.707(1), b = 14.951(3), c = 14.986(2) A,β = 92.40(2)°, V = 1725.2(8) A3, Dm = 1.61(1) g cm−3, Dc = 1.62 g cm−3, R = 0.032 and Rw = 0.035 for 2016 observed reflections. The CuN2O2O′chromophore can be described as square pyramidal strongly distorted towards trigonal bipyramidal. The basal coordination positions are occupied by the two oxygen atoms of the bidentate oxalate group, the coord…
Cobalt(II) and copper(II) assembling through a functionalized oxamate-type ligand
2014
Two new metal complexes of formula {[Co(Hpcpa)(H2O)3]n� 3/2nH2O} (1) and [Cu2(MeHpcpa)4(MeOH)2] � H2O� 3.68 MeOH (2 )[ H 3pcpa = N-(4-carboxyphenyl)oxamic acid and MeH2pcpa = methyl ester derivative of H3pcpa] have been synthesized and their structures determined by X-ray diffraction. 1 is a neutral zigzag chain of cobalt(II) ions bridged by Hpcpa 2� ligands exhibiting the bidentate/monodentate coordination mode. Each cobalt(II) ion is six-coordinate with three mer positioned water molecules, two oxamate-oxygens from a Hpcpa 2� ligand and a carboxylate-oxygen from another Hpcpa 2� group building a somewhat distorted octahedral surrounding. The intrachain cobalt–cobalt separation is 11.326(2…
Copper(II) assembling with bis(2-pyridylcarbonyl)amidate and N,N'-2,2-phenylenebis(oxamate).
2013
We herein present the synthesis and X-ray structures of five copper(II) complexes of formulae [Cu(bpca)(CF3SO3)(H2O)]·H2O (1), [Cu(bpca)(Phpr)(H2O)]·3/2H2O (2), {[Cu(bpca)]2[Cu(opba)(H2O)]}·H2O (3), {[Cu(bpca)]2(H2opba)}2·6H2O (4) and [Cu(bpca)(EtH2opba)]n (5), where bpca = bis(2-pyridylcarbonyl)amidate, Phpr = 3-phenylpropionate, CF3SO3(−) = triflate (anion of the trifluoromethanesulphonic acid), H4opba = N,N′-1,2-phenylenebis(oxamic acid), and EtH3opba = monoethyl ester derivative of the H4opba. 1 and 2 are mononuclear copper(II) complexes where the copper atom is five-coordinate in distorted square pyramidal surroundings with a tridentate bpca and a water molecule (1)/carboxylate oxygen …
Ferromagnetic coupling in the malonato-bridged copper(ii) chains [Cu(Im)2(mal)]nand [Cu(2-MeIm)2(mal)]n(H2mal = malonic acid, Im = imidazole and 2-Me…
2002
Two new malonato-bridged copper(II) complexes of formula [Cu(Im)2(mal)]n (1) and [Cu(2-MeIm)2(mal)]n (2) (Im=imidazole, 2-MeIm=2-methylimidazole and mal=malonate dianion) have been prepared and their structures solved by X-ray diffraction methods. The [Cu(Im)2(mal)] and [Cu(2-MeIm)2(mal)] neutral entities act as monodentate ligands towards the adjacent copper(II) units through one of the two carboxylate groups, the OCO bridge exhibiting an anti-anti conformation. The environment of each copper atom in 1 and 2 is distorted square pyramidal: two carboxylate oxygen atoms from a bidentate malonate and two nitrogen atoms from two imidazole (1) or 2-methylimidazole (2) ligands form the equatorial…