Search results for "COPP"

Innesto di catene polimeriche sulla superficie di nanotube di carbonio mediante reazione di accoppiamento radicalico

2015

La modifica di nanotubi di carbonio (CNT) attraverso innesto (grafting) di catene polimeriche sulla loro superficie è un metodo efficace per promuovere la dispersione di queste cariche a livello nanometrico in una matrice polimerica. La funzionalizzazione covalente di CNT con catene polimeriche viene generalmente ottenuta sia attraverso crescita controllata di polimeri a partire dalle pareti della nanocarica mediante metodi "grafting from" sia attraverso metodi di "grafting to" che si basano sulla reazione di condensazione tra polimeri preformati e CNT opportunamente modificati. In questo lavoro viene proposto un nuovo approccio di tipo "grafting to" per innestare catene polimeriche su CNT …

Strong Ferromagnetic Coupling in Linear Mixed μ-Acetato, μ-Hydroxo Trinuclear Copper(II) Complexes withN-sulfonamide derivatives − Synthesis, Structu…

2002

New strategies in the development of polynuclear complexes. Crystal structure of the tetranuclear copper(II) complex [Cu4(L1)2(OH)4Cl2(H2O)2]2(H3O2)(…

2000

Abstract The preparation and interaction of the new polyaza[n]naphthalenophanes 2,5,8,11-tetraaza[12](1,4)naphthalenophane (L1) and 2,6,9,13-tetraaza[14](1,4)naphthalenophane (L2) with hydrogen ions and Cu2+ is described. The crystal structure of the new tetranuclear copper(II) complex [Cu4(L1)2(OH)4Cl2(H2O)2]2(H3O2)(ClO4)2Cl·2H2O (L1=2,5,8,11-tetraaza[12](1,4)naphthalenophane) is presented and discussed. A variety of intra- and intermolecular forces contribute to the particular organisation of the crystal. The solution studies indicate the formation of similar tetranuclear species for L1 while for L2 just mononuclear 1:1 species are detected.

Magnetic properties of a binuclear copper(II) complex [Cu(terpy)Cl] (PF6)

1982

Discrete trinuclear copper(II) compounds as building blocks: the influence of the peripheral substituents on the magnetic coupling in oxamato-bridged…

2014

Two new trinuclear copper(ii) complexes without end-capping ligands, (Bu4N)2[Cu(dmso)2{Cu(dnopba)(dmso)}2] () and (Bu4N)2[Cu(dmso)2{Cu(dcopba)(dmso)}2] () [dnopba = 4,5-dinitro-ortho-phenylenebis(oxamate), dcopba = 4,5-dichloro-ortho-phenylenebis(oxamate), Bu4N(+) = tetra-n-butylammonium and dmso = dimethylsulfoxide], were synthesized and their structures were determined by single crystal X-ray diffraction. The crystal structures of and consist of two outer bis(oxamato)(dmso)cuprate(ii) units which act as bidentate ligands toward a trans-bis(dmso)copper(ii) inner entity leading to centrosymmetric tricopper(ii) complexes with copper-copper separations across the oxamate bridges of 5.1916(3) …

New route to a face-to-face biscorrole free-base and the corresponding heterobimetallic copper(III)-silver(III) complex.

2004

A meso-aryl-substituted face-to-face biscorrole was synthesised in a two-step reaction and the corresponding homo- and heterobimetallic complexes were obtained and fully characterised.

Structure and Magnetic Properties of the Ferromagnetic Cu3Cl126- Trimer in [(NH3C2H4)3NH]2Cu3Cl14

2004

The crystal structure consists of a strongly hydrogen bonded network of tris(N-ethylammonium)ammonium cations, Cu3Cl12(6)- trimeric species, and Cl- anions. The Cu3Cl12(6)- trimers are formed by two distorted tetrahedral CuCl4(2)- anions linked to a central square planar CuCl4(2)- anion via semicoordinate Cu-Cl...Cu mu1 bridges. The central copper ion shows only small deviations from ideal D4h symmetry, while the terminal copper ions show a mild distortion from D2d symmetry with an average trans Cl-Cu-Cl angle of 136.0 degrees. The semicoordinate linkages provide a ferromagnetic exchange pathway between the copper ions with J/k = 6.91(3) K. Short Cl...Cl contacts (3.67-3.90 angstoms) lead t…

Polymorphism of Copper(I) Halide π-Complexes: Synthesis and Structure of a New Modification of [Cu2Cl2(CH2=CH–CH2)2O]

2008

A new polymorph of [Cu2Cl2(CH2=CH-CH 2)2O] has been obtained by an alternating-current electrochemical synthesis starting from CuCl2 and triallylphosphite. Diallylether was obtained in statu nascendi via transetherification of triallylphosphite. The structure is monoclinic, space group P21/n, a = 7.6738(7), b = 6.5128(4), c = 18.2689(18) A, β = 91.644(11)°, V = 912.67(13) A3 (at 150 K), Z = 4; R1 = 0.0339, wR2 = 0.0822. Flexibility of the organic ligand and weak interactions copper⋯halogen have been identified as the main reasons enabling polymorphism in molecular π-complexes of copper(I). ©2008 Wiley-VCH Verlag GmbH & Co. KGaA.

An Azide-Bridged Copper(II) Ferromagnetic Chain Compound Exhibiting Metamagnetic Behavior

1997

The one-dimensional chain complex [Cu(2)(mgr;(2)-1,1-N(3))(2)(mgr;(2)-1,3-NO(3))(2)(mgr;(2)-1,3-Me(3)NCH(2)CO(2))(2)](n)() (1) contains three different bridge groups,mgr;(2)-1,1-azide (end-on),mgr;(2)-nitrate, andmgr;(2)-syn,syn-carboxylate, arranged so that the azide and carboxylate groups bridge equatorially and dictate the intrachain magnetic behavior between the copper magnetic orbitals. Variable-temperature magnetic susceptibility studies at low field, and magnetization studies at variable field, reveal dominant intrachain ferromagnetism (J = 26 cm(-)(1)) but also much weaker interchain ferromagnetism (THETAV; = 2.3 K) and antiferromagnetism (J(eff) = -0.18 cm(-)(1)). The structure has…

Ligand Effects on the Structure and Magnetic Properties of Alternating Copper(II) Chains with 2,2′-Bipyrimidine- and Polymethyl-Substituted Pyrazolat…

2014

A novel series of heteroleptic copper(II) compounds of formulas {[Cu2(μ-H2O)(μ-pz)2(μ-bpm)(ClO4)(H2O)]ClO4·2H2O}n (1), {[Cu2(μ-H2O)(μ-3-Mepz)2(μ-bpm)](ClO4)2·2H2O}n (2), and {[Cu2(μ-OH)(μ-3,5-Me2pz)(μ-bpm)(H-3,5-Me2pz)2](ClO4)2}n (3) [bpm = 2,2'-bipyrimidine, Hpz = pyrazole, H-3-Mepz = 3-methylpyrazole, and H-3,5-Me2pz = 3,5-dimethylpyrazole] have been synthesized and structurally characterized by X-ray diffraction methods. The crystal structures of 1 and 2 consist of copper(II) chains with regular alternating bpm and bis(pyrazolate)(aqua) bridges, whereas that of 3 is made up of copper(II) chains with regular alternating bpm and (pyrazolate)(hydroxo) bridges. The copper centers are six- (1…