Structure of a binuclear copper(II) complex with both μ-alkoxo and μ-formato bridges, [Cu2(C17H15N2O3)(HCOO)]

Binuclear copper(ii) and nickel(ii) complexes based on N,N′-bis(3-formyl-5-tert-butylsalicylidene)-1,3-diaminopropan-2-ol: physicochemical and theoretical study

“…Almost in all complexes having a "distorted" ("asymmetrical") con formation, copper(II) ions are weakly  2 coordinated by a DMF (see or DMSO molecule. 39 The copper(II) complex with N,N´ bis(salicylidene) 1,3 di aminopropan 2 ol containing an exogenous formate bridge 45 is the only complex of this type with the distorted struc ture, in which the metal ion is not additionally coordinat ed by a solvent.…”

Ferromagnetic exchange in μ-alkoxo-μ-dicarboxylato double bridged tetranuclear copper(II) complexes: [Cu4(L-X)2(μ-C4H4O4)(dmf)2] (L=1,3-bis(5-X-salicylideneamino)-2-propanol, X=Br, Cl)

“…The solid curves for 1 in Fig. 2 represent the best fit of the experimental data obtained with J = 54 cm À1 , g = 2.01, h = À0.76 K and R = 1.5 · 20 À5 for 1, J = 56 cm À1 , g = 2.0, h = À0.73 K, and R = 2.5 ·10 À5 for 2, respectively, where the discrepancy R value is defined as P ½ðv m T Þ obs À ðv m T Þ calc 2 = P ½ðv m T Þ obs 2 .At this stage, we suggest that the magnetic behavior of 1 and 2, like other heterobridged complexes, in principle should be explained by two-step perturbation process [1,17,[20][21][22][23][24]. In the first step, without second bridging carboxylato ligand, overlaps of the symmetric (d s ) and antisymmetric (d a ) combinations of the magnetic orbitals with the oxygen p orbitals take place to form new symmetric ðd 0 s Þ and antisymmetric ðd 0 a Þ combinations, where d 0 s > d s ; d 0 a > d a , and the relative energies of d 0 s and d 0 a depend on the structural parameters of the alkoxo bridging moiety.…”

“…Evidently, most of the l-hydroxo/alkoxo-l-X systems, exception of X ¼ RCO À 2 , are antiferromagnetically coupled, in which their structural feature shown that the dihedral angles between two coordination planes of copper(II) ions are nearly planar. The structures and magnetism of binuclear Cu(II) complexes with both l-alkoxo-l-carboxylato/l-halogens bridges have been system studied to reveal the orbital counter-complementary effect [17,[20][21][22][23]. These Cu(II) complexes are usually antiferromagnetic with the Cu-O-Cu angle greater than 130°.…”

“…These Cu(II) complexes are usually antiferromagnetic with the Cu-O-Cu angle greater than 130°. However, the antiferromagnetic interaction is suppressed to present ferromagnetic coupling by the so-called roof-shaped distortion [10,12,17,[20][21][22][23][24], which is measured by the dihedral angle (d) between two copper coordination planes.Recently, we have reported two new ferromagnetic coupled (2J = 33.4 and 52 cm À1 ) l-alkoxo-l-7-azaindolato double bridged dicopper(II) complexes which also show a roof-shaped coordination site of two copper(II) coordination planes with dihedral angle of 112.8°and 118.6° [24]. In order to develop new types of l-alkoxol-dicarboxylato heterobridged tetranuclear copper(II) been particularly interested to use dicarboxylato as a double bridging moiety because it was anticipated that its introduction will induce considerable twist in the complex molecules to bring about significant change in their magnetic exchange interactions.…”

“…These Cu(II) complexes are usually antiferromagnetic with the Cu-O-Cu angle greater than 130°. However, the antiferromagnetic interaction is suppressed to present ferromagnetic coupling by the so-called roof-shaped distortion [10,12,17,[20][21][22][23][24], which is measured by the dihedral angle (d) between two copper coordination planes.…”