Amna S. A. Zidan

Mixed Ligand Complexes of 5-arylazo-8-hydroxyquinoline and α-amino Acids with Co(II), Ni(II) and Cu(II)

Ten mixed ligand complexes of the type [M(X-QA)(aa)] and [Ni(X-QA)2(Haa)(H2O)],where X-HQA=5-arylazo-8-hydroxyquinoline derivatives, M=Co(II) orCu(II) and Haa=glycine (gly), alanine (ala) or methionine (met), have been prepared. The complexes have been characterized by elemental analysis, IR and electron spectra and thermal analysis. A tetrahedral structure has been proposed for the cobalt(II) and copper(II) complexes with bidentate coordination of amino acids. The nickel(II) complexes have been assigned an octahedral structure with the amino acids acting as monodentate ligands. The thermal behaviour of the complexes has been studied before and after γ-irradiation.

Mixed Ligand Complexes of Nickel (II) Dialkyldithiophosphates with 2-Acetylpyridine Semicarbazone and 2-Acetylpyridine Benzoylhydrazone

Dialkyldithiophosphates nickel (II) complexes react with Apsc and HApBH to yield mixed ligand complexes of the types [Ni{(RO) 2 PS 2 } 2 (Apsc)] and [Ni {(RO) 2 PS 2 }(ApBH)] where R = methyl, ethyl, or propyl; Apsc = 2-Acetylpyridine semicarbazone; HApBH = 2-Acetylpyridine benzoylhydrazone. From the elemental analysis and UV, IR, and mass spectra the composition and structures of the complexes and the ligand (HApBH) were determined. TG and DTG techniques were used to investigate the thermal behavior of HApBH and the complexes. The IR spectra show that Apsc acts in a neutral bidentate fashion and HApBH behaves in all cases as a mononegative tridentate ligand. The electronic spectral data suggest an octahedral structure of these complexes. Also the biological activity for some of the complexes and HApBH was recorded against some bacteria and fungi. The HApBH ligand has a high toxicity against bacteria and fungi under study; this may be due to presence of the pyridyl ring and hydroxyl group of the compound.

Complexes of tris(o-phenanthroline)nickel(II) and copper(II) bromide with dithiocarbamates derived from α-amino acids

Complexes of 1,10-o-phenanthroline (o-phen)-NiII and CuII with dithiocarbamates derived from α-amino acids (glycine, phenylalanine, alanine, methionine and tryptophan) were synthesized and characterized by chemical analysis, spectral and thermal studies and by biological screening; the complexes are non-electrolytes. The empirical formula are [Ni(o-phen)2(aadtc)] and [Cu2(o-phen)2(phaladtc)(H2O)2Br2] where, aadtc = glycinyl-, phenylalaninyl-, alaninyl-, methioninyl- and tryptophanyldithiocarbamate and phaladtc = phenylalaninyldithiocarbamate. The structure of these complexes is probably octahedral. Molecular association through hydrogen bonding between the —NH and the carboxylate groups is proposed for the NiII complexes. The CuII complex is dimeric with the phenylalaninyldithiocarbamate acting as a bridge.

Characterization of Some New Nickel(II) Dithiolato Mixed Ligand Complexes With Nitrogen Donor Ligands: Magnetic, Spectral, and Thermal Studies

Abstract The following mixed ligand complexes were prepared and characterized: (Etdtp)2Ni (Boz)2, (Etdtp)2Ni (Btz)2, (Cydtp)2Ni (Btz)2 (Etxan)2Ni (Boz)2, (Etxan)2Ni (Btz)2, (Mexan)2Ni (morph)2, (Prxan)2Ni (morph)2, (Buxan)2Ni (morph)2, (Acac)2Co(Boz)2, (Acac)2Co(Btz)2, (Acac)2Ni(Boz)2, and (Acac)2Ni (Btz)2. Etdtp [dbnd] diethyldithiophosphate, Cydtp [dbnd] dicyclohexyldithiophosphate, Mexan [dbnd] methylxanthate, Etxan [dbnd] ethylxanthate, Prxan [dbnd] propylxanthate, Buxan [dbnd] butylxanthate, Acac [dbnd] acetylacetonate, Boz [dbnd] benzoxazole, Btz [dbnd] benzothiazole, and morph [dbnd] morpholine. The compounds were identified on the basis of their elemental analysis, IR and UV-VIS spectra, magnetic measurements, and thermal analysis.

Anionic complexes of some transition metals containing mixedβ-diketonato and alkylxanthato ligands

SummaryEleven complexes of the type K[M(acac)(Rxan)2] and K[M(TTA)2(Rxan)], where M=CoII or NiII, acac=acetylacetonate, TTA=thenoyltrifluoroacetonate, and Rxan=alkylxanthate, R=methyl-, ethyl-, propyl-, butyl-, or cyclohexyl-, have been prepared. The magnetic and spectral data indicate that the complexes are octa-hedral and that the xanthate group is attached in a bidentate fashion to the metal ions. The conductivity data are commensurate with the ionic character in the complexes. T.g.a. were made for some of the complexes.

Studies on some transition metal mixed ligands complexes: Glycinyldithiocarbamate and 8-hydroxyquinoline moiety

This paper reports the isolation and characterisation of mixed ligand complexes of the types Ba[M(Ox)2glydtc], [M2′(Ox)4glydtc], [M2(QA)2glydtc] and [M2′(QA)4glydtc] (where glydtc=glycinyldithiocarbamate; HOx=8-hydroxyqinoline;HQA=p-methyl-5-phenylazo-8-hydroxyquinoline and M=Co(II),Ni(II) or Cu(II); M′=Fe(III) or Cr(III). The structures for the complexes have been elucidated on the basis of elemental analysis, electronic, IR and mass spectroscopy. Electronic spectral data for the complexes were in accordance with an octahedral environment around the central metal ions in all metal chelates except for [Co2(QA)2glydtc] and [Ni2(QA)2glydtc] where the structure around Co(II) and Ni(II) may be tetrahedral. The complexes were proposed to be dimeric except those of Ba[M(Ox)2glydtc]. A study of the thermal decomposition of the complexes has also been carried out. For Ba[M(Ox)2glydtc], elimination of carbon dioxide was observed. However, evolution of nitrogen and formation of tolyl radicals occur for [M2(QA)2glydtc] and [M2′(QA)4glydtc]. Kinetic parameters for the various decomposition stages were calculated using the Coats–Redfern and Horowitz–Metzgerequations.

Lewis acidity of coordinatively unsaturated bis(2-mercaptobenzothiazolato)nickel(II) towards azoles and morpholine

The reactions of bis(2-mercaptobenzothiazolato)nickel(H) with some azoles and morpholine afforded the corresponding mixed ligand complexes. The studied azoles were 2-aminothiazole, benzothiazole, benzoxazole, 2-methylbenzoxazole and 2-mercapto-benzoxazole. The formation of new compounds was confirmed from the spectral data. The thermal decompositions of the compounds together with some related compounds reported in the literature, for comparison, were studied. The activation energies and other kinetic parameters were calculated from the Coats-Redfern and Horowitz-Metzger equations.ZusammenfassungDie Reaktion von Bis(2-mercaptobenzothiazolato)nickel(II) mit einigen Azolen und Morpholin liefert die entsprechenden Mischligandenkomplexe. Die untersuchten Azole waren 2-Aminothiazol, Benzothiazol, Benzoxazol, 2-Methylbenzoxazol und 2-Mercaptobenzoxazol. Die Bildung neuer Verbindungen wurde anhand von Spektren festgestellt. Es wurde die thermische Zersetzung von einigen dieser Verbindungen sowie zum Vergleich auch von einigen in der Literatur beschriebenen verwandten Verbindungen untersucht. Anhand der Coats-Redfern- und der Horowitz-Metzger-Gleichung wurden die Aktivierungsenergien und andere kinetische Parameter errechnet.

Synthesis and Investigation of Mixed‐Ligand Transition Metal Complexes of Alkyl Dithiocarbonate and Benzoylhydrazine or Benzoylhydrazone Derivatives

Abstract Mixed‐ligand complexes of the types [Ni(Etdtcn)(BH)], [Ni(Budtcn) (BeBH)], and [M(Rdtcn)(salBH)], where M = Co(II), Ni(II), or Cu(II); R = methyl (Me), ethyl (Et), propyl (Prop) or butyl of the dithiocarbonate (Bu); dtcn = dithiocarbonate group; BH = benzoyl‐hydrazine anion, BeBH = benzaldehyde benzoylhydrazone anion, and salBH = salicylaldehyde benzoylhydrazone anion have been synthesised. Elemental analyses, molar conductivities, and spectral (IR, UV, and mass) studies have been used to elucidate the structure of the metal complexes. HBH and HBeBH coordinate in the enol form as bidentate ligands forming a square‐planar structure around Ni(II). Moreover, the HsalBH ligand behaves as tridentate anion with all metal ions and an octahedral structure for these complexes is proposed. The three ligands and some of their complexes were screened against three species of bacteria, namely B. cereus (G +ve), P. aeruginosa (G −ve), and S. aureus (G +ve) and five types of fungi, A. flavus, A. fumigatus var. albus, A. niger, F. oxysporum or C. tropicum. The HsalBH ligand has shown high activity against bacteria and fungi, probably due to the presence of a hydroxyl group in this ligand.

Studies of mixed ligand complexes from dialkyldithiophosphate and thiosemicarbazide or thiosemicarbazones with nickel(II)

The complexes [Ni{(RO)2PS2}2Tsc], [Ni{(RO)2PS2}2ApTsc], and [Ni{(RO)2PS2}FurTsc.2H2O] where R = methyl (Me), ethyl (Et) or propyl (Prop); Tsc = thiosemicarbazide, ApTsc = 2-acetylpyridine-thiosemicarbazone, and FurTsc = furfuraldhydethiosemicarbazone have been synthesized and characterized by elemental analysis, conductance measurements, and spectral studies (IR, UV-Vis, and mass). Thermal studies of the complexes have been carried out using TG and DTG techniques. An octahedral structure has been proposed for all types of the complexes. A representative types of the complexes are tested against various pathogenic bacteria and fungi. The [Ni{(EtO)2PS2}2ApTsc] shows a high degree of activity against bacteria and fungi; this may be attributed to the pyridyl ring of the 2-acetylpyridinethiosemicarbazone ligand.

Complexes of bis(Diphehyldithiophosphinato)nickel(II) with Nitrogen and Sulphur Containing Ligands

Abstract Mixed ligand complexes of bis(diphenyldithiophosphinato)nickel(II) with some azoles and morpholine (morph) having the general formula Ni (Ph2PS2)2(azole)2 or Ni (Ph2PS2)2 (morph)2 have been prepared. Displacement reactions between bis(diphenyldithiophosphinato)-nickel(II) and dithizone (H2Dz), sodium diethyIdithiocarbamate (NaEt2dtc) Or potassium cyclohexyldithiocarbanate (Cydten) produced the mixed ligand complexes Ni(Ph2PS2) (HDz), Ni (Ph2PS2) (Et2dtc) and Ni(Ph2PS2) (Cydtcn). The newly prepared compounds were characterised on the basis of their analysis, magnetic susciptibility, infrared, electronic spectra as well as thermal analysis.