STUDIES OF THE S-ETHYLTHIOSEMICARBAZONES WITH CU(I), ZN(II), CD(II), HG(II) CHLORIDE SALTS

Thiosemicarbazone derivatives, R-C6H4-CH=N-N=(C-S-C2H5)-NH2 . HBr [R = H (L), (CH3)(2)N (L')], were prepared by a modified general method. Complexes of Cu(I), Zn(II), Cd(II), Hg(II) chloride salts with ligands L and L' were isolated in two different solvents, and have the following stoichiometries: [Hg(L)Cl-2](x) prepared in CH2Cl2 and [Zn(L)Cl-2]. 2H(2)O, [Cd(L)Cl-2](2) . CdCl2 . C2H5OH . 4H(2)O, [Hg(L)Cl-2]. 1/2C(2)H(5)OH, [Cu(L)Cl-2](x), [Cd(L')Cl-2]. CdCl2 . C2H5OH . 2H(2)O, [Hg(L' HBr)]Cl-2 prepared in absolute ethanol. The complexes were characterized by analytical data, UV, IR and H-1 NMR spectroscopy

Studies of metal complexes of 2-(2-pyridinyl)-, 2-(6-methyl-2-pyridinyl)-, 2-(3-pyridinyl)-1H-benzimidazoles with some d(8-10) ions

2-R-1H-Benzimidazoles [L-1, R = 2-pyridinyl; L-2, R = 6-methyl-2-pyridinyl; L-3, R = 3-pyridinyl] and their complexes with Ni(II), Pd(II), Zn(II), Cd(II), Hg(II) chloride were prepared. The complexes, having 1:1 and 1:2 metal:ligand ratios, were characterized by elemental analyses, magnetic susceptibility and molar conductance measurements, IR and H-1 NMR spectroscopy. The Ni(II) complexes are paramagnetic. The metal:ligand ratio are 1:1 in the Pd(II) and Hg(II) complexes of the ligands, and these complexes are non-ionic. in the IR spectra the band character and vibrational frequencies of the groups participating in coordination changed on complexation In the H-1 NMR spectra, considerable changes were found in the chemical shifts of protons neighboring to the coordinated nitrogen atoms. The ligands L-1 and L-2 give chelates easily with the metal ions, but L-3 does not

Thermal decomposition of N-1,N-4-diarylidene-S-methylthiosemicarbazone dioxouranium(VI) templates

The solvated dioxouranium(VI) complexes [UO2(L)S] (S = H2O, methyl, ethyl-, iso-amyl-, n-octyl- and n-undecyl-alcohol) were prepared from salicyl- and 5-bromosalicylaldehyde S-methylthiosemicarbazones. The templates were characterized by elemental analysis, IR and UV-Vis spectroscopy, magnetic susceptibility, and molar conductivity. The thermal stability of the compounds was investigated in air depending on the solvent molecule

Zinc(II) complexes of 2-(2-hydroxy-5-bromo/nitro-phenyl)-5-methyl/chloro/nitro-1H-benzimidazoles

2-(2-Hydroxyphenyl)-5-R-1-1H-benzimidazoles [R-1=H ((LM)-M-1), CH3 ((LH)-H-2), Cl ((LH)-H-3), NO2 ((LH)-H-4)], 2-(2-Hydroxy-5-R-2-phenyl)-1H-benzimidazoles [R-2=Br ((LH)-H-5), NO2 ((LH)-H-6)] and their Zn(NO3)(2) complexes were synthesized, characterized by elemental analysis, molar conductivity, IR and H-1-NMR spectra. (LH)-H-1, (LH)-H-2, (LH)-H-4 and (LH)-H-6 give a complex with Zn(NO3)(2) in general formula Zn(L-n)(2); however, (LH)-H-3 and (LH)-H-5 complexes are in [Zn(L-n)(2)](HNO3)(2) form. The substituent effect on the characteristic of the ligands and the complexes was investigated

Nickel(II)-triphenylphosphine complexes of ONS and ONN chelating 2-hydroxyacetophenone thiosemicarbazones

The complexes [Ni(L-1)(PPh3)] (1) and 1Ni(L-2)(PPh3)]-HCI (2) were synthesized by the reaction of [Ni(PPh3)Cl-2] and dibasic 2-hydroxyacetophenone-S-R-4-R-1-thiosemicarbazones (R/R-1: H/CH3, (LH2)-H-1; CH3/H, (LH2)-H-2). The ligands and the complexes were characterized using elemental analysis, IR and H-1 NMR spectra. In both complexes, the thiosemicarbazone ligands coordinate to nickel(II) by giving two protons. Complex 1 is formed through the phenolate oxygen, azomethine nitrogen and sulfur atoms of L-1 and the P acorn of a triphenylphosphine ligand. In complex 2, L-2 is functional through an ONN donor set, containing a thioamide nitrogen instead of a sulfur atom. X-ray analysis indicated distorted square planar structures for the complexes, and the nickel atoms lie slightly above the planes structured by the donor atoms. In the crystal forms of 1 and 2, some phenyl ring protons of the phosphine ligand give intramolecular hydrogen bonds with the donor atoms of the thiosemicarbazone moiety, namely the phenolate oxygen (in complexes 1 and 2) and N-4 nitrogen (in complex 2). (C) 2011 Elsevier Ltd. All rights reserved

N-1,N-4-diarylidene-S-ethylthiosemicarbazone iron(III) and nickel(II) complexes

Template reactions of salicyl-, 5-bromosalicyl- and 2-hydroxy-1-naphth-aldehyde with S-ethylthiosemicarbazones, in the presence of FeCl3 and NiCl2, yielded the corresponding N-1,N-4-di(same/different)arylidene-S-ethylthiosemicarbazone complexes, which were characterized by elemental analysis, magnetic measurements, i.r. and H-1-n.m.r. spectra

Synthesis and Characterization of New Nickel(II) Chelates With S-Alkyl-Salicylaldehyde Thiosemicarbazones

The template reactions of salicylidene-, 5-bromosalicylidene-, and 3,5-dichlorosalicylidene-S-R-thiosemicarbazone (R: propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, dodecyl) with 5-bromo- and 3,5-dichlorosalicylaldehyde in the presence of nickel(II) yielded N-1,N-4-diarylidene-S-alkyl-thiosemicarbazone chelates. The N2O2 type complexes were isolated as stable solid compounds and characterized by elemental analysis, electronic, infrared, H-1 NMR, and mass spectroscopies. The magnetic susceptibility measurements at room temperature (r.t.) indicate the diamagnetic nature of the complexes. The relationship between melting point (mp) values of the nickel(II) template complexes and the chain length of alkyl moiety was clearly shown

Unusual template condensation of benzophenone thiosemicarbazones and salicylaldehydes with nickel(II)

Reactions of 5-R-2-hydroxybenzophenone S-methylthiosemicarbazones (R: H, Br, Cl) and 2-hydroxy-benzaldehydes in the presence of NiCl2 yielded template complexes by chelating with two of the ligands in the monoanionic form. The N4O2 complexes of the thiosemicarbazones show distorted-octahedral geometry around nickel(II). The compounds were characterized by elemental analysis, conductivity and magnetic measurements, UV-Vis, IR, 1H-NMR, and mass spectra. Crystal structure of bis-N1-(2-hydroxy-5-bromo-phenyl)(phenyl)methylene-N4-(2-hydroxy-phenyl)methylene-S-methyl-thiosemicarbazidato-Ni(II) was determined by single-crystal X-ray diffraction

Asymmetric N2O2 complexes of iron(III) and nickel(II) obtained from acetylacetone-S-methyl-thiosemicarbazone: synthesis, characterization and electrochemistry

Iron(III) and nickel(II) complexes from acetylacetone-S-methyl-thiosemicarbazone were synthesized and characterized. The thiosemicarbazidato structures of N2O2 are N-1-acetylacetone, N-4-salicyl/3-methoxy/5-bromo-/3,5-dichlorosalicylidene. The square-pyramidal iron(III) and square-planar nickel(II) complexes of N-1-acetylacetone-N-4-3-methoxy thiosemicarbazidato were determined by X-ray diffraction. Electrochemical characterizations of the complexes were carried out by using cyclic voltammetry and square wave voltammetry. While nickel(II) complexes only give ligand based reduction and oxidation reactions, iron(III) complexes give reversible Fe-III/Fe-II reduction in addition to the ligand based processes. Changing of the substituents on the ligand, shifts the redox processes and also affects the stabilities of the electrogenerated species. With respect to the reduction potential of Fe-III/Fe-II couple, the most easily reduced complex was 3,5-dichloro substituted complexes and the most difficult to reduce was the 3-methoxy substituted one

Zinc(II) Complexes of Acetophenone and 5-Chloro-2-hydroxy-benzophenone Thiosemicarbazones. Synthesis, Characterization, and Nonlinear Optical Properties from Quantum Chemical Calculations

A number of mixed ligand complexes of zinc(II) with acetylacetone, acetophenone thiosemicarbazone, and 5-chloro-2-hydroxy-benzophenone thiosemicarbazone ligands were synthesized. The complexes [Zn(L)(acac)(2)] were characterized by elemental analysis as well as by IR and H-1 NMR spectroscopy. The structure of the zinc(II) complex of acetophenone thiosemicarbazone (1) was determined by single crystal X-ray diffraction. Complex 1 crystallizes in the monoclinic space group P21/c with Z = 4. In vacuo geometry optimization and electronic calculation have been performed using Density Functional Theory (DFT) without any symmetry constraints for the compounds. Experimental and calculated data indicated that the thiosemicarbazone ligand acts as monodentate ligand through the sulphur atom and the complex adopts distorted square-pyramidal geometry, which consists of the sulphur atom and four oxygen atoms of the acetylacetone moieties. Polarizability (alpha), first hyperpolarizability (beta), frontier orbital energies, and dipole moment (mu) are also reported for ligands L-1, L-2, and complexes 1 and 2