A. M. Shallaby

New uranyl(VI) complexes with hydrazone-oximes derived from aromatic acid hydrazides and biacetylmonoxime—I

Abstract Several new uranyl(VI) complexes of some hydrazone-oximes, derived from o -chloro-, o -methyl-, o -hydroxy-, p -chloro-, p -methyl-, p -nitro-, p -methoxybenzoylhydrazines and biacetylmonoxime, have been synthesized in absolute ethanol. The isolated solid complexes have been characterized by elemental analysis, molar conductance, molecular weights, spectral (i.r., u.v., NMR) and magnetic measurements. The ν (UO) stretching frequency of the complexes occurs at ca 920 cm−1

Dioxouranium(VI) complexes of 3-benzamidorhodanine and its substituted derivatives

Abstract The synthesis and characterization of some dioxoyranyl(VI) complexes containing-3-benzamidorhodanine and its substituted derivatives as ligands are reported. The structure of complexes is discussed on the basis of spectral (UV, IR and NMR), elemental analyses, conductivities, molecular weights and thermal analysis (DSC, DTA, TGA and TG) results. IR spectra show that the ligands are bidentate coordinating via the amide nitrogen (NH) and the carbonyl oxygen of rhodanine in the enol form with displacement of a proton from the latter group. Also, NMR studies suggest that the enolization and coordination occurs via the carbonyl oxygen of rhodanine and not through the carbonyl of the amide moiety. Finally, the thermal studies suggest the existence of a cis -form for the isolated uranyl complexes.

Metal Complexes of a Schiff Base Formed by Condensation of S-Benzyl-dithiocarbazate with Biacetylmonoxime (H2BTC)

Abstract The synthesis and characterization of Co(III), Ni(II), Cu(II), Zn(II), Cd(II) and UO2 2+ complexes of biacetylmonoxime-hydrazine-S-benzyldithiocarbazate (H2BTC) are reported. Elemental analyses, 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 Co(III) complex while a square-planar structure is proposed for both Ni(II) and Cu(II) complexes on the basis of magnetic and spectral measurements.

New uranyl(VI) complexes with ons ligand derived from aromatic acid hydrazides and phenyl isothiocyanate. part III

SummaryThe synthesis and characterization of some dioxouranium(VI) complexes containing potential ONS donor ligands derived from benzoyl,o-chloro-,o-methyl-,P-chloro-,p-nitro-,p-methoxy-,p-aminobenzoylhydrazines and isonicotinylhydrazine with phenyl isothiocyanate are reported. Two types of complexes with general formulae [UO2(HL)2(X)2] and [[UO2(HL)2] have been identified and characterized. All the uranyl complexes are of the [UO2(HL)2(X)2] type (HL=bidentate monoanionic ligand, X=H2O and/or EtOH) and X bridges the uranyl ion and the thioketo groupvia hydrogen bonding. Upon heating to 140 °C, the complexes lose X giving a new complex of formula [UO2(HL)2] (HL=tridentate monoanionic ligand) in which the thioketo-group participates in bonding. The latter complexes take up X again on exposure to water and/or ethanol vapour.

Reactions of cyanoacetylhydrazine complexes with salicylaldehyde and consequent metal-promoted reactions

Abstract The reactions of salicylaldehyde with a suspension of cyanoacetylhydrazine and/or malonic acid amido-hydrazide complexes in aqueous ethanolic solutions afford novel complexes. The structures of the isolated complexes have been elucidated by conventional physical and chemical measurements. The absence of the cyano group band at 2270 cm−1 in the IR spectra of all complexes, except those of CO(II) and Ni(II) complexes, suggests the promotion of H2O to the cyano group (CN) forming amido group. Several structures have been proposed in which salicylaldehyde behaves differently toward the cyanoacetylhydrazine complexes. Also, 1-salicylhydrazo-3-imino-3-(o-formyl) phenoxy propionic acid hydrazide is synthesized either by extraction from the isolated solid complexes using disodium ethylene-diaminetetraacetate or during refluxing of Co(II) and/or Fe(II) complexes with salicylaldehyde. This novel compound is confirmed by elemental analysis, spectra (IR and 1H NMR) and mass spectra.

Metal Complexes and Metal Promoted Reactions of Salicylaldehyde Cyanoacetylhydrazone in Ethanol. Part III

Abstract The complexes of salicylaldehyde cyanoacetylhydrazone (H2L1) and its derivative, 1-salicylhydrazo-3-imino-3-ethoxy-propionic acid hydrazide (H2L2), have been isolated and characterized by conventional physical and chemical methods. H2L1 complexes are only obtained on using metal acetate. Use of chloride, bromide, or sulphate counter ions results in the acid catalyzed addition of ethanol to coordinated H2L1 to give complexes of H2L2. IR spectral data indicate that H2L1 coordinates in a tridentate manner via the azomethine nitrogen, the OH (phenolic) and the enolized carbonyl oxygen, while H2L2 bonds through the azomethine nitrogen, carbonyl oxygen and the OH (phenolic) with displacement of a hydrogen atom from the OH (phenolic) in case of the enol form. The stereochemistry of Co(II), Ni(II) and Cu(II) complexes has been discussed and elucidated with the help of magnetic and spectral measurements.

Synthesis of New Metal Complexes Derived from Cyanocetylhydrazone (SCH) and its Derivatives with Some Transition Metal Ions in Isopropanol and Tert-Butanol. (IV)

Abstract The synthesis and characterization of cobalt(II), nickel(II), copper(II), zinc(II) cadmium(II), mercury(II) and U(VI)O2 complexes containing salicylaldehyde cyanoacetylhydrazone (SCH), 1-salicyl-hydrazo-3-imino-3-isopropoxy propionic acid hydrazide (SIPPH) and 1-salicylhydrazo-3-imino-3-tert-butoxy propionic acid hydrazide (SIBPH) are reported. The metal complexes have been characterized on the basis of elemental analyses, spectra (NMR, IR, visible), molar conductivities and magnetic moments measurements. Infrared spectral data show that the ligands (SCH, SIPPH and SIBPH) behave in a tridentate and/or bidentate manner with different modes of coordination toward the metal ions. The stereochemistry of the Co(II), Ni(II) and Cu(II) complexes has also been discussed. Moreover, a polymeric structure via an imido group (C[dbnd]NH) for some Cu(II) complexes is considered. Finally NMR spectra of the ligands and some diamagnetic complexes are discussed.

Metal Complexes and Metal Promoted Reactions of Cyanoacetylhydrazine (CAH)

Abstract Reactions of cyanoacetylhydrazine (CAH = H2L) with Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and U(VI)O2 in ethanolic solution give three types of complexes with the general formulae, [M(H2L)2X2] S(M = Co(II), Ni(II) or Cd(II); X = Cl− or Ac−; S=EtOH or (H2O), [M(HL)2]S(M = Co(II), Cu(II), Zn(II) or U(VI)O2 and S = H2O and [Hg(HL)Cl.H2O]. On the other hand, the reaction of Fe(III) chloride, Cu(II) chloride or bromide with CAH in aqueous ethanolic solution is accompanied by the reduction to Fe(II) and Cu(I) giving complexes with the formulae [Fe(H2L)2(H2O)2]Cl2 (H2L = CAH) and [Cu(H2L−)X] (H2L− = malonic acid amido-hydrazide, X = Cl− or Br−), respectively. The reduction process followed by the addition of H2O to the triple bond (C−=N), forming malonic acid amido-hydrazid, is only observed in case of Cu(I) complexes. Characterization of the isolated solid complexes have been made on the basis of elemental analyses, spectral (u.v., visible, i.r., n.m.r.) and magnetic measurements.

Synthesis and Characterization of Some Transition Metal Complexes Derived from Dimedone bis(S-Benzyldithiocarbazic Acid)

Abstract Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of 4,5-dimethyl-1,3-cyclohexanone bis(S-benzyldithiocarbazic acid), H2DSB, have been synthesised and characterized by elemental analysis, molar conductance, spectral (i. r., visible and n.m.r.) and magnetic moment measurements. I. r. spectra show that H2DSB behaves as a bidentate SS donor system in the copper chloride complex and a tetradentate SNNS donor system in the other complexes. Different stereochemistries are proposed for Co(II), Ni(II) and Cu(II) complexes on the basis of spectral and magnetic studies. The diamagnetic nature of Cu(H2DSB)2Cl.H2o suggest the reduction of Cu(II) to Cu(I). The molar conductivities for all complexes are reported in the range of non-electrolytes except that of the [Ni(H2)DSB)]Cl2.2H2O complex which suggest that it is a 1:2 electrolyte.

The Role of Cu(II) in the Addition of Ethanol to the Cyano Group and the Preparation of Novel Organic Compounds

The addition of ethanol to the cyano group of salicyl-aldehyde cyanoacetylhydrazone (SCH) is catalyzed by Cu(II) chloride, bromide, and sulphate, while it remains unchangeable in complexes derived from Cu(II) acetate. The isolated Cu(II) complexes have been characterized by conventional physical and chemical methods. Infrared spectra indicate that the ligand coordinates in a tridentate and/or bidentate manner. The stereochemistry of these Cu(II) complexes is discussed and elucidated with the help of magnetic and spectral measurements. The novel organic compound, l-salicylhydrazo-3-imino-3-ethoxypropionic acid hydrazide (SIEPH), was synthesized and its structure confirmed by elemental analysis and spectrophotometry techniques.