R. A. Alieva

Copper(II) complex with 3-(2-hydroxy-3-sulfo-5-nitrophenylhydrazo)pentane-2,4-dione: Synthesis and structure

AbstractThe copper(II) complex with 3-(2-hydroxy-3-sulfo-5-nitrophenylhydrazo)pentane-2,4-dione (H3L) is studied, and its crystal structure is studied by X-ray diffraction analysis. The crystals of [Cu(H2O)2]2(μ-L)2[Cu(H2O)4] (I) are triclinic (space group P

Thermodynamic characteristic of complex formation of some metals with 3-(4-chlorophenylazo)pentane-2,4-dione in aqueous ethanol

nbar 1n

Copper(II) complex with thienyltrifluoroacetylacetone and dimethyl sulfoxide: Synthesis and crystal structure

) at 100 K, a = 7.085(3), b = 10.373(5), c = 12.265(6) Å, α = 0.842(5)°, β = 104.996(6)°, γ = 99.156(6)°, Z = 1). The C=O and NH groups of hydrazone and the OH and SO3H groups from the aromatic moiety of the molecule are involved in coordination with the copper(II) atom. In the centrosymmetric trinuclear molecule the central Cu(2) atom has the coordination number six, and the terminal Cu(1) atoms have the coordination number five. The thermal properties of complex I are studied. The complex formation of copper(II) with the H3L ligand in an aqueous solution at temperatures 298 ± 0.5, 308 ± 0.5, and 318 ± 0.5 K is studied by potentiometric titration. The standard thermodynamic functions of the complex formation are determined.

Nickel(II) complex with 4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dione and dimethyl sulfoxide: Crystal and molecular structures

The effective atomic charges in the tautomeric forms (enol-azo, keto-azo, and hydrazo) of 3-(2-hydroxy-5-nitro-3-sulfophenylazo)pentane-2,4-dione (L1), 3-(2-hydroxy-3,5-disulfophenylazo)pentane-2,4-dione (L2), 3-(5-chloro-2-hydroxy-3-sulfophenylazo)pentane-2,4-dione (L3), 3-(2-hydroxy-4-nitrophenylazo)pentane-2,4-dione (L4), and 3-(2-hydroxyphenylazo)pentane-2,4-dione (L5) were calculated by the Hückel method (MO LCAO). It was found that the hydrazo form is most reactive for meta- and meta’-substituted derivatives (L1–3) and the keto-azo form is most reactive for para-substituted (L4) and unsubstituted ones (L5). The stability constants of complexes of rare-earth metals (La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) with L1–5 determined by potentiometric titration decrease in the order: Lu > Yb > Tm > Er > Ho > Dy > Tb > Gd > Eu > Sm > Nd > Ce > La. Functionalization of the aromatic part of ligands L affected neither the rare-earth metal: L ratio (1: 2) nor the above order of the stability constants.

Crystal structure of the copper(II) complex with acetylacetone and ethylenediamine obtained by template synthesis

AbstractEffective charges of atoms in tautomeric forms (enol-azo, keto-azo, hydrazo) of 3-(4-chlorophenylazo) pentane-2,4-dione (L) have been determined by MO LCAO in the Hückel approximation. The complex formation of a series of metals with L in aqueous ethanol has been investigated by potentiometric and conductometric titration. Based on the results of potentiometric titration, the standard thermodynamic functions of complex formation have been established. They vary in the following order:

Crystal structure of the complex of copper(II) with 3-(2-hydroxy-3-sulfo-5-nitrophenylazo)-pentadione-2,4

nbegin{gathered}n left| {Delta G^0 } right|:Fe > Cu > Co > Ni > UO_2 > Cd > Zn > Mn > Mg > Ca, hfill n left| {Delta H^0 } right|:Fe > Cu > UO_2 > Ni > Co > Zn > Cd > Mn > Mg > Ca, hfill n Delta S^0 :Ca > Mg > Mn > Cd > Co > Zn > Ni > Cu > Fe > UO_2 . hfill nend{gathered} n