Authors:K. Mészáros Szécsényi, T. Wadsten, B. Carson, É. Bencze, and G. Liptay
Compounds obtained by a solid–gas phase reactions between copper(II) chloride and bromide and 2,4-, 2,6- 3,4- and 3,5-lutidines
were studied using thermogravimetry, far-infrared, electronic spectroscopy and X-ray diffraction. The results were compared
with the corresponding data for the similar compounds with methylpyridines and 2,4,6-collidine. A special attention was paid
to the host-guest phenomenon, a new structural feature of transition-metal halide complexes.
Authors:K. Mészáros Szécsényi, V. Leovac, Ž. Jaćimović, V. Češljević, A. Kovács, G. Pokol, and S. Gál
We report the synthesis and the characterization (elemental analysis, FT-IR spectroscopy, thermal methods and molar conductivity
measurements) of the mixed complexes of zinc with acetate and 3-amino-5-methylpyrazole, HL1, [Zn(OAc)2(HL1)2], or 3-amino-5-phenylpyrazole, HL2 [Zn(OAc)2(HL2)2], or 4-acetyl-3-amino-5-methylpyrazole, HL3, [Zn(OAc)(L3)(HL3)]2, with isothiocyanate and HL2 [Zn(SCN)2(HL2)2], or HL3 [Zn(SCN)2(HL3)2], and with nitrate, isothiocyanate and 3,5-dimethyl-1-carboxamidinepyrazole, HL4 [Zn(NO3)(NCS)(HL4)2].
The thermal decomposition of the complexes is generally continuous resulting zinc oxide as end product,except [Zn(OAc)(L3)(HL3)]2 in which case a well-defined intermediate was observed between 570–620 K. On the basis of the IR spectra and elemental analysis
data of the intermediate a decomposition scheme is proposed.
Authors:Z. Leka, V. Leovac, S. Lukić, T. Sabo, S. Trifunović, and K. Szécsényi
(NH4)3L, a new dithiocarbamato
derivative of iminodiacetate, has been synthesized. The coordination properties
of the ligand were tested in reactions with copper(II), nickel(II) and palladium(II)
salts in acidic solutions. Complexes with a general formula M(H2L)2
were obtained, with the coordination taking place through the sulfur atoms
of the dithiocarbamate moiety. The new compounds were characterized by elemental
analysis, UV/VIS and IR spectroscopy, thermal analysis and magnetic measurements.
In addition, the ligand was characterized by 1H-
and 13C-NMR spectroscopy and molar conductivity
measurements. The copper(II) complex is paramagnetic, while the nickel(II)
and palladium(II) compounds are diamagnetic. The thermal decomposition of
all compounds is continuous and the thermal stability of the complexes is
higher than that of the ligand, as expected.
Authors:K. Mészáros Szécsényi, V. Leovac, Ž. Jaćimović, V. Češljević, A. Kovács, and G. Pokol
The synthesis of copper(II) chloride complexes with 3,5-dimethylpyrazole, 1-carboxamidine-3,5-dimethylpyrazole, 5-amino-4-carboxamide-1-phenylpyrazole
and 4-acetyl-3-amino-5-methylpyrazole is described. The compounds are characterized by elemental analysis, FT-IR spectroscopy,
thermal methods, magnetic moment and molar conductivity measurements. Thermal decomposition of the dichloro-(3,5-dimethylpyrazole)-copper(II)
complex results in an unstable intermediate with a stochiometric composition. The decomposition of the other compounds is
Authors:V. M. Leovac, K Mészáros Szécsényi, Lj. S. Vojinović Ješić, V. I. ćešljević, S. Markov, and T. Wadsten
Complex formation reactions of copper(II)
and zinc(II) halides with pyridoxilidene Girard-T hydrazone dihydrate [H3PLGT]Cl2·2H2O and salicylidene Girard-T hydrazone [H2SalGT]Cl
ligands are described. The composition of the complexes, determined by customary
methods, can be presented by the formulas Cu(HPLGT)X2
(X=Cl– and Br–
), Zn(HPLGT)Cl2, Cu(HSalGT)Cl2·H2O
The structures of the compounds were compared by powder X-ray diffraction.
Thermal stability of the compounds has been examined by TG and DSC. The ligands
and the complexes were tested against some gram-positive and gram-negative
bacteria and yeast.