Search results for "COPP"

Influence of Xantphos Derivative Ligands on the Coordination in Their Copper(I) and Silver(I) Complexes

2019

Structure and magnetic properties of [(REDA)Cl]2CuCl4 salts: A new series of ferromagnetic layer perovskites

2005

Abstract The preparation, structure and magnetic properties of two mono- N -substituted ethylenediammonium copper chloride salts are reported. Both [(MEDA)Cl] 2 CuCl 4 and [(EEDA)Cl] 2 CuCl 4 assume monoclinic layered perovskite A 2 CuCl 4 type structures (here MEDA 2+ is the N -methylethylenediammonium dication and EEDA 2+ is the N -ethylethylenediammonium dication). In these structures, planar CuCl 4 2 - ions are linked together into layers of corner-sharing distorted octahedra via semi-coordinate Cu⋯Cl bonds. The magnetic studies reveal the presence of dominant ferromagnetic coupling in both compounds and analysis of the higher temperature data yielded J / k  = 19.29(1) K and 19.0(4) K f…

Copper(I) Complexes of Bis(2-(diphenylphosphino)phenyl) Ether:  Synthesis, Reactivity, and Theoretical Calculations

2007

The tricoordinated cationic Cu-I complex [Cu(kappa(2)-P,P'-DPEphos)(kappa(1)-P-DPEphos)][BF4] (1) (DPEphos = bis(2-(diphenylphosphino)phenyl) ether) containing a dangling phosphorus center was synthesized from the reaction of [Cu(CH3CN)(4)][BF4] with DPEphos in a 1:2 molar ratio in dichloromethane. When complex 1 is treated with MnO2, elemental sulfur, or selenium, the uncoordinated phosphorus atom undergoes oxidation to form a PE bond resulting in the formation of complexes of the type [Cu(kappa(2)-P,P'-DPEphos)(kappa(2)-P,E-DPEphos-E)][BF4] (2, E = O; 3, E = S; 4, E = Se) containing a Cu-E bond. The zigzag polymeric Cu-I complex [Cu(kappa(2)-P,P'-DPEphos)(mu-4,4'-bpy)](n)[BF4](n) (5) was …

Synthesis, Characterization, and X-ray Crystal Structures of Cyclam Derivatives. 5. Copper(II) Binding Studies of a Pyridine-Strapped 5,12-Dioxocycla…

2004

The copper(II) binding properties of the macrobicyclic diamide 1,9,12,18,22-pentaazatricyclo[7.6.6.1(3,7)]docosa-3,5,7(22)-triene-13,19-dione (L1) have been fully investigated by spectroscopic (IR, UV-vis, EPR, MALDI-TOF MS), X-ray diffraction, potentiometric, electrochemical, and spectroelectrochemical methods. This constrained receptor possesses a hemispherical cavity created by cross-bridging the 1 and 8 positions of trans-dioxocyclam (1,4,8,11-tetraazacyclotetradecane-5,12-dione, L2) with a 2,6-pyridyl strap. Treatment of L1 with a copper salt in methanol produces a red complex of [Cu(L1H(-1))]+ formula in which the copper atom is embedded in a 13-membered ring and coordinated by both a…

Synthesis and spectral studies ofN-2-pyridinylcarbonyl-2-pyridinecarxoximidate copper(II) complexes

1987

Dimeric and polymeric copper(II) complexes containing BPCA (N-2-pyridinylcarbonyl-2-pyridinecarboximidate), having general formulae Cu(BPCA)X·nH2O (X=Cl, Br, NCS, NCO, N3, or CN) and Cu2(BPCA)2-X·nH2O [X=oxalate anion (OX), chloranilate anion (CA) or the dianion of 2,5-dihydroxy-1,4-benzoquinone (DHBQ)] have been synthesized by the copper(II)-assisted hydrolysis of 2, 4, 6-tris(2-pyridyl)-1, 3, 5-triazine. Spectroscopic results indicate five-coordinate, approximately square-pyramidal, geometry around the copper(II) ion. Half-field absorption in the ΔMs=±2 region of the X-band e.p.r. powder spectra has been observed for the dimeric species.

Coordinating behaviour of a new pyridylhydrazone; tris-complexes of manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) with 2-pyridylcarb…

1991

The preparation and characterization oftris-complexes of MnII, CoII, NiII, CuII and ZnII with a new pyridylhydrazone, 2-pyridylcarbaldehyde-N,N-dimethylhydrazone (pch), are described. In all the complexes pch behaves as a bidentate ligand binding through the pyridine and azomethyne nitrogen atoms. The complexes appear to be monomeric, high spin six-coordinate, and a distorted octahedral stereochemistry around the metal is suggested. The e.p.r. results for both CuII compounds indicate a mainly dx2−y2 ground state with a static Jahn-Teller distortion, whilst for the MnII complex the e.p.r. data indicates a very low symmetry for the MnN6 polyhedron.

Cimetidine complexes derived from cobalt(II), nickel(II) and copper(II) salts of polyatomic anions

1986

Cobalt(II), nickel(II) and copper(II) complexes [M(CM)2]X2 (X = BF4 or NO3) have been prepared with cimetidine (CM). Powder data, molar conductivities, magnetic moments, i.r. and electronic spectra support apseudo-octahedral stereochemistry with MN2N 2 ⋆ S2 chromophore and tentative structures are proposed for the complexes. Their properties are compared with these of previously prepared complexes.

Versatile supramolecular self-assembly. Part I. Network formation and magnetic behaviour of the alkaline salts of the bis(malonate)cuprate(ii) anion

2006

Five malonate-containing copper(II) compounds of formula {[A(H2O)n]2 [Cu(mal)2(H2O)m]} [A = Li (1), Na (2), K (3), Rb (4) and Cs (5); H2mal = malonic acid] have been synthetized and characterized by X-ray diffraction. The structure of these compounds consists of bis(malonate)cuprate(II) anions and alkaline cations that are held together by means of carboxylate bridges and water molecules leading to 3D networks. A study of the self-assembling of the bis(malonate)cuprate(II) and the alkaline cations is carried out, the size of the alkaline metal ion playing an important role in the control of the resulting malonate-bridged copper(II) structure. A regular alternation of layers of anionic malon…

Synthesis, Characterization and Magnetic Properties of New Dinuclear Copper(II) Complexes with N,N′-Disubstituted Dithiooxamides derived from α-Amino…

2005

Four new dinuclear copper(II) complexes have been synthesized and have the general formula [Cu2(L)(H2O)2], where L = GLYDTO [N,N′-bis(carboxymethyl)dithiooxamide], ALADTO [N,N′-bis(carboxyethyl)dithiooxamide], VALDTO [N,N′-bis(1-carboxy-2-methylpropyl)dithiooxamide] and LEUDTO [N,N′-bis(1-carboxy-3-methylbutyl)dithiooxamide]. The complexes were characterized by elemental analysis as well as by IR, electronic and EPR spectroscopy. These techniques provided evidence for the presence of the CuNO2S chromophore. Magnetic susceptibility measurements on all the complexes in the range 4–300 K show the existence of a dominant antiferromagnetic interaction with −J values greater than 300 cm−1. Therma…

Electrocatalytic reduction of dioxygen to water by tren-capped porphyrins, functional models of cytochrome c oxidase

1999

International audience; Two different tren-capped porphyrins—in which the two metals, iron and copper, are more or less off-centered—are shown to be efficient catalysts for the reduction of O2 to H2O; surprisingly, their iron-only complexes are shown to be even more effective 4e- catalysts when adsorbed on a graphiteelectrode.