Kamal M. Ibrahim

Metal complexes of schiff's base derived from salicoylhydrazine and biacetylmonoxime

Biacetylmonoxime-salicoylhydrazone (BMSH) complexes of the types [Hg(BMSH)Cl2] and [M(BMSH-H)2], where M = Cu(II), Co(II), Ni(III), Mn(II), Zn(II), Cd(II) and UO2(VI), have been prepared and characterized by conventional chemical and physical measurements. The IR spectra show that the ligand usually coordinates via carbonyl oxygen (CO), azomethine nitrogen (CNl) and phenolic OH with replacement of hydrogen by metal ions but acts as a bidentate molecule coordinating through (CO) and (CNl) in the Hg(II) complex. The magnetic and spectral data of the Co(II) and Ni(II) complexes support octahedral stereochemistry, whilst tetragonally distorted octahedral geometry is suggested for the Cu(II) complex.

Synthesis of Some Transition Metal Complexes Derived from 1-Valeroyl-4-phenyl-3-thiosemicarbazide

Abstract The synthesis and characterization of metal complexes of some dipositive metal ions with 1-valeroyl-4-phenyl-3-thiosemicarbazide (VTSC) is reported. The data of elemental analysis, molar conductivities, magnetic measurments and spectral (i.r., visible) studies have been used to elucidate the structure of the complexes. I.r spectra show that VTSC acts as a bidentate ligand and coordinates via 2NH and the enolic carbonyl oxygen (=C-OH) of the hydrazide moiety with the displacement of a hydrogen atom from the latter group. The values of molar conductivities in DMF indicate the non-electrolytic nature of all metal chelates. A tetrahedral structure is proposed for [Co (VTSC-H) Ac], square-planar for [Ni (VTSC-H) Ac] and [Cu (VTSC-H) Ac]H2O complexes, and octahedral for [Ni (VTSC-H)2. 2H2O]2H2O and [Co (VTSC-H)2.2H2O]2H2O complexes according to the data of magnetic and electronic spectral measurments.

Synthesis and magnetic, spectral and thermal eukaryotic DNA studies of some 2-acetylpyridine- [N-(3-hydroxy-2-naphthoyl)] hydrazone complexes

Complexes of Ni(II), Co(II), Cu(II), Zn(II), Cd(II), Hg(II) and U(VI)O2 with 2-acetylpyridine-[N-(3-hydroxy-2-naphthoyl)] hydrazone (H2APHNH) have been prepared and characterized by elemental analysis, molar conductance, thermal (TG, DTG), spectral (1H NMR, IR, UV–Vis, ESR) and magnetic measurements. 1H NMR spectrum of the ligand suggests the presence of intramolecular hydrogen bonding. IR spectra show that H2APHNH is a bidentate, tridentate and/or tetradentate ligand. Thermal decomposition of some complexes ended with metal oxide as a final product. ESR spectra gave evidence for the proposed structure and the bonding for some Cu(II) complexes. Biological activity measurements were carried out.

Synthesis and Structural Studies of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) Chelates Derived From Semicarbazide and Thiosemicarbazide Derivatives

Abstract The synthesis and characterization of cobalt(II), nickel(II), copper(II), zinc(II) and cadmium(II) chelates containing 1-anthranyl-4-phenyl-3-semicarbazide (APSC) and/or 1-anthranyl-4-phenyl-3-thiosemicarbazide (APTSC) are reported. The chelates have been characterized on the basis of elemental analyses, spectra (NMR, IR, visible), magnetic moments, conductivities and molecular weight measurements. The values of molar conductivities in DMP or DMSO indicate the non-ionic nature of all metal chelates. A tetrahedral structure is proposed for the Ni(II) chelates, square-planar for the Cu(II) chelates and tetrahedral or octahedral for the Co(II) chelates according to the data of magnetic measurements and electronic spectra. The ligands (APSC, APTSC) behave in a bidentate manner toward the metal ions, but with different coordination sites. 1HNMR spectra of the ligands and the diamagnetic chelates are discussed. The chelates have a monomeric or a polymeric nature.

Co(II), Cd(II), Hg(II) and U(VI)O2 complexes of o-hydroxyacetophenone[N-(3-hydroxy-2-naphthoyl)] hydrazone: Physicochemical study, thermal studies and antimicrobial activity

The o-Hydroxy acetophenone [N-(3-hydroxy-2-naphthoyl)] hydrazone (H(2)o-HAHNH) has been prepared and its structure is confirmed by elemental analysis, IR, (1)H NMR and (13)C NMR spectroscopy. It has been used to produce diverse complexes with Co(II), Cd(II), Hg(II) and U(VI)O(2) ions. The isolated complexes have been investigated by elemental analysis, magnetic measurements, molar conductivity, thermal (TG, DTG) and spectral ((1)H NMR, (13)C NMR, IR, UV-visible, MS) studies. Infrared spectra suggested H(2)o-HAHNH acts as a bidentate and/or tridentate ligand. The electronic spectrum of [Co(Ho-HAHNH)(2)] complex as well as its magnetic moments suggesting octahedral geometry around Co(II) center. The TG analyses suggest high stability for most complexes followed by thermal decomposition in different steps. Moreover, the kinetic and thermodynamic parameters (Ea, A, ΔH, ΔS and ΔG) for the different decomposition steps of the [Co(Ho-HAHNH)(2)] and [Cd(Ho-HAHNH)(2)] complexes were calculated using the Coats-Redfern and Horowitz-Metzger methods. Moreover, the antibacterial and antifungal activities of the isolated compounds were studied using a wide spectrum of bacterial and fungal strains.

Ligational behaviour of biacetylmonoxime nicotinoyl hydrazone (H2BMNH) towards transition metal ions

SummaryThe synthesis and characterization of MnII, CoII, NiII, CuII, ZnII, CdII UO22+, CrIII and FeIII complexes of biacetylmonoxime nicotinoyl hydrazone (H2BMNH) are reported. Elemental analysis, molar conductance, magnetic moment and spectral (i.r., visible and n.m.r.) measurements have been used to characterize the complexes. I.r. spectral data show that the ligand behaves in a bidentate and/or tridentate manner. An octahedral structure is proposed for the MnII, NiII, CrIII and FeIII complexes, while a square-planar structure is proposed for both CoII and CuII complexes on the basis of magnetic and spectral measurements.

Synthesis and characterization of new metal complexes of thiosemicarbazone derived from 4-phenyl-3-thiosemicarbazide and chromone-3-carboxaldehyde

SummaryThe reaction between chromone-3-carboxaldehyde-4-phenylthiosemicarbazone (HCPT) and some hydrated metal salts of CoII, NiII and CuII give complexes of the type [Cu(HCPT)Cl2],[Cu(CPT)BrH2O],[Cu(CPT)2]·2H2O, [Ni(CPT)2(H2O)2]·2H2O, [Co(CPT)2(OAc)] and [Co(CPT)2(H2O)2]X·2H2O (where X=Cl or Br). The metal complexes were characterized by elemental analyses, molar conductivities, and spectal (i.r. and visible) and magnetic studies. I.r. spectra show that the HCPT coordinates in the thione or thiol form and behaves in a bidentate manner. Also, HCPT behaves as an oxidizing agent towards CoII forming diamagnetic CoIII complexes. An octahedral structure is proposed for both CoIII and NiII complexes, while a square-planar structure is proposed for CuII complexes on the basis of magnetic and spectral measurements.

Structural Studies of 1-Isatin-4-phenyl-3-thiosemicarbazone and 1 - (α-) Furyl-4-phenyl-3-thiosemicarbazone Complexes

Abstract New metal complexes derived from 1-isatin-4-phenyl-3-thiosemicarbazone (IPTS) and 1-(α-) furyl-4-phenyl-3-thiosemicarbazone (PPTS) with Ni(II), Co(II), Cu(II) and Cd(II) have been synthesized and characterized on the basis of elemental analyses, magnetic moments, molar conductivities and spectral (NMR, Visible, IR) measurements. IR spectra show that IPTS coordinates in a tridentate manner via CN, CO and CS groups, while FPTS acts as a bidentate ligand coordinating via CN and CO groups. Magnetic and spectral studies suggest a square-planar structure for the Cu(II) and Ni(II) complexes which are derived from FPTS and a low-spin octahedral structure for [Co(FPTS-H)3]· 2H2O. On the other hand, octahedral structures are proposed for the complexes of Ni(II) and Cu(II) that are derived from IPTS and a low-spin octahedral structure for [Co(IPTS-H)2]. 1HNMR spectra of the ligands and the diamagnetic complexes are discussed.

Bivalent metal complexes ofp-methyl- andp-methoxybenzoylhydrazone oximes

SummaryBivalent metal complexes ofp-chloro-,p-methyl- andp-methoxybenzoylhydrazone oximes (H2BMCB, H2BMMB or H2BMTB=H2L), [M(H2L)Cl2]. nH2O (M=ZnII, CdII or HgII, n=0 or 1; [M(H2L)Cl2] (M=ZnII or CdII); [M(HL)2(H2O)n]. YH2O (M=CoII, CuII, ZnII or UVIO2, n=0–2); [Ni(H2BMCB)(H2O)3]Cl2, [Ni(BMMB)(H2O)]2 and [Ni(BMTB)(H2O)]2, were synthesized by conventional physical and chemical measurements. I.r. spectra show that the ligands are bidentate or tridentate. Spectral, magnetic and molecular weight measurements suggest that cobalt(II) and nickel(II) have monomeric octahedral geometry when derived from H2BMCB, a dimeric square planar geometry for nickel(II) and monomeric square planar geometry for cobalt(II) for those isolated from H2BMMB or H2BMTB. Also, a monomeric distorted octahedral structure is proposed for copper(II) complexes derived from the ligands under investigation.

Spectral, thermal and magnetic studies of biacetylmonoxime isonicotinoylhydrazone complexes

Abstract The synthesis and characterization of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and UO2+2 complexes of biacetylmonoxime isonicotinoylhydrazone (BMINH) are reported. Elemental-analysis, magnetic, thermal and spectral (IR, visible and NMR) measurements have been used to characterize the complexes. IR spectral data show that the ligand behaves in a bidentate and/or tridentate manner. An octahedral structure is proposed for the Ni(II) complexes, while a square-planar structure is proposed for both Co(II) and Cu(II) complexes, on the basis of magnetic and spectral measurements.