Diperoxo Complexes of Vanadium(V) Containing Mannich Base Ligands

The vanadium(V) peroxo complexes containing Mannich base ligands having composition Na[VO(O₂)₂(L‐L)]·H₂O [where L‐L=morpholinobenzyl acetamide (MBA), piperidinobenzyl acetamide (PBA), morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), morpholinomethyl benzamide (MMB), piperidinomethyl benzamide (PMB), morpholinobenzyl formamide (MBF), piperdinobenzyl formamide (PBF)] have been reported. The complexes have been prepared by stirring vanadium pentoxide with excess of 30% aqueous‐H₂O₂ followed by treatment with ethanolic solution of the ligand and finally maintained the pH of the reaction mixture by adding dilute solution of sodium hydroxide. The synthesized complexes have been characterized by various physico‐chemical techniques, via elemental analysis, molar conductivity, magnetic susceptibility measurements, infra red, electronic, mass, ¹H NMR spectral and TGA/DTA studies. These studies revealed that the synthesized complexes are uni‐univalent electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen and the ring nitrogen. Thermal analysis result provides conclusive evidence for the presence of one molecule of lattice water in the complexes. Mass spectra confirm the molecular mass of the complexes.     

Peroxo Complexes of Molybdenum(VI) Containing Mannich Base Ligands

The molybdenum(VI)-peroxo complexes containing Mannich base ligands having a formula as [MoO(O2)2(L-L)] [where L-L＝morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), morpholinobenzyl urea (MBU), piperidinobenzyl urea (PBU), morpholinobenzyl thiourea (MBTU), piperdinobenzyl thiourea (PBTU)] have been synthesized and characterized by physico-chemical, electrochemical techniques and TGA/DTA studies. The complexes have been prepared by stirring ammonium molybdate and excess of 30% aqueous-H2O2 and then treatment with ethanolic solution of the ligand. Studies revealed that these complexes were non-electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen/thiocarbonyl sulphur and the ring nitrogen. The cyclic voltammograms of the complexes show two quasi-reversible steps involving complexes. The complexes have also been tested for antibacterial activity against Salmonella and Kleibsella. The antibacterial study of the ligands and complexes indicate that the complexes exhibit higher activity than the free ligands.     

Synthesis and characterization of oxodiperoxo complexes of tungsten(VI) with some Mannich base ligands

Six oxodiperoxotungsten(VI) complexes, [WO(O₂)₂L–L] (where L–L?=?morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), piperidinobenzyl urea (PBU), morpholinobenzyl urea (MBU), piperidinobenzyl thiourea (PBTU) and morpholinobenzyl thiourea (MBTU)) have been prepared by stirring WO₃?·?H₂O with excess 30% aqueous (w/v) H₂O₂ and then treating with an ethanolic solution of the Mannich base ligand (L–L). These have been characterized by elemental analysis, conductance and magnetic susceptibility measurements, IR spectra, electronic spectra, ¹H NMR, TGA/DTA and cyclic voltammetric studies. These complexes are non-electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen/thiocarbonyl sulphur and the ring nitrogen. The complexes also inhibit the growth of pathogen “Fusarium Spp.” up to 60%. The cyclic voltammograms of the complexes indicate quasi-reversible redox steps involving complexes.     

Synthesis and characterization of peroxo complexes of uranium(VI) with some Mannich base ligands

Abstract  

Uranium(VI) peroxo complexes of composition [UO(O₂)L–L(NO₃)₂], where L–L are the Mannich base ligands morpholinobenzyl urea, piperidinobenzyl urea, morpholinobenzyl thiourea, piperidinobenzyl thiourea, morpholinomethyl thiourea, piperidinomethyl thiourea, or morpholinomethyl urea, are reported. The synthesized complexes were characterized by use of a variety of physicochemical techniques, viz. elemental analysis, molar conductivity, magnetic susceptibility measurements, IR, electronic, mass, ¹H NMR, and ¹³C NMR spectroscopy, and TGA/DTA studies. These studies revealed that the complexes are both non-electrolytic and diamagnetic in nature. The ligands are bound to the metal in a bidentate mode through carbonyl oxygen or thiocarbonyl sulfur and the ring nitrogen. Mass spectra confirm the molecular mass of the complexes. The antifungal activity of the complexes is greater than that of the corresponding free ligands.     

Dinuclear peroxo complexes of molybdenum(VI) containing Mannich base ligands

Dinuclear molybdenum(VI) peroxo complexes containing Mannich base ligands having formulae [Mo₂O₄(O₂)₂L-L(H₂O)₂] · H₂O [where L-L = N-[1-morpholinobenzyl] acetamide (MBA), N-[1-piperidinobenzyl] acetamide (PBA), N-[1-morpholino(-4-nitrobenzyl)] benzamide (MPNBB), N-[1-piperidino(-3-nitrobenzyl)] benzamide (PMNBB), N-[1-morpholino(-2-nitrobenzyl)] acetamide (MONBA), and N-[1-morpholino(-3-nitrobenzyl)] acetamide (MMNBA)] have been synthesized by stirring ammonium heptamolybdate with excess 30% aqueous hydrogen peroxide followed by treatment with ethanolic solution of corresponding ligands. The complexes have been characterized by elemental analysis, molar conductance, magnetic measurements, infrared (IR), electronic, TGA/DTA, mass spectral, and ¹H NMR studies. The complexes are non-electrolytes and diamagnetic. The IR spectral studies suggest that the ligands are bidentate to metal through carbonyl oxygen and ring nitrogen. Thermal analyses provide conclusive evidence for the presence of coordinated, as well as lattice water in the complexes. Dinuclear complexes preserve the individuality of the molybdenum oxo peroxo core. The complexes exhibit higher antibacterial activity against bacterium Ralastonia solanacearum (Pseudomonas solanacearum) than the free ligands.     

Synthesis and characterization of peroxo complexes of uranium(VI) with aroylhydrazone ligands

The uranium(VI) peroxo complexes containing aroylhydrazones ligands having composition [UO(O₂)L-L(NO₃)₂]·H₂O (where L-L = Benzoic acid[1-(Furan-2-yl)methylene] hydrazide, Benzoic acid[(thiophene-2-yl)methylene] hydrazide, Benzoic acid[1-(thiophene-2-yl)ethylidene] hydrazide, Benzoic acid(phenylmethylene) hydrazide, Benzoic acid[1-(anisol-3-yl)methylene] hydrazide and Benzoic acid[(p-chlorobenzyl)methylene] hydrazide are reported. The complexes were characterized by various physico-chemical techniques, viz. elemental analysis, molar conductivity, magnetic susceptibility measurements, infra red, electronic, mass spectral and TGA/DTA studies. These studies revealed that complexes are non-electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode. Thermal analysis results provide conclusive evidence for the presence of water molecules in the complexes. Mass spectra confirm the molecular mass of the complexes. Antifungal activity of complexes revealed enhanced activity of complexes as compared to the corresponding ligands.     

Phosphineborane analogs of trimethylsilyl amides

The reaction of (CH₃)₂(BH₃)PCl with the lithium salts of acetamide, N-methyl acetamide, and N-methyl formamide produced the N(CH₃)₂(BH₃)P-monosubstituted amides. Attempts to employ the same procedure for the preparation of the bis-acetamide, the acetanilide and the N-methyl benzamide derivatives were unsuccessful. Variable temperature NMR spectroscopy revealed the presence of rotational isomers for the formamide with a population of 0.85 for the major rotamer which on the basis of the ³¹P-formyl proton coupling constants was assigned the structure where the (CH₃)₂(BH₃)P group is trans to carbonyl oxygen. The free energies of activation were determined to be 16.2 and 17.3 kcal/mol. For the other derivatives only one isomer could be detected down to—60°C. The compounds are similar to the trimethylsilyl analogs in structure and rotational populations, but the lower rotational barrier in the phosphineborane formamide derivative suggests a greater destabilization of the polar ground state amide resonance structure by the formal positive charge on phosphorus.     

Thermodynamic Parameters of Solvation and Complexing of Copper(II) Nitrate and Nickel(II) Nitrate in Water + Acetamide Mixtures at 298.15 K

The heats of mixing of aqueous solutions of copper(II) or nickel(II) nitrate in water + acetamide (AA) mixtures in the existing range of amide concentrations have been studied. A rise in the amide concentration enhances solvation more strongly in copper(II) salt solutions. Data are analyzed with reference to previous results on the enthalpies of transfer of the salts studied in water + formamide (FA) and water + N,N-dimethylformamide (DMF) mixtures. Electronic absorbance spectra have been recorded at a fixed electrolyte concentration for all thermochemically studied systems, and a linear correlation has been found between the enthalpy of transfer of Cu(NO₃)₂ and the optical density of the solution. The enhanced solvation of copper(II) nitrate in aqueous acetamide is due to inner-sphere interactions between the cation and acetamide; that of nickel(II) nitrate is more due to outer-sphere interactions.     

Die photochemische synthese von μ-(1-2-η:2-3-η-allen)-octacarbonyldimangan(0)

Novel dihydroiridium(III) complexes containing mono- and bi-dentate sulfur ligands have been isolated. The cationic complexes [Ir(COD)L₂]ClO₄ (COD = 1,5-cyclooctadiene, L = tetrahydrothiophene (tht) or trimethylene sulfide (tms); L₂ = (CH₃S)₂(CH₂)₃ (dth)), [Ir(COD)(L-L)]₂(ClO₄)₂ (L-L = 1,4-dithiacyclohexane (dt) or (t-BuS)₂(CH₂)₂ (tmdto)) and [Ir(CO)₂(tmdto)]₂-(ClO₄)₂ react with H₂ to give the corresponding iridium(III) dihydrides: [IrH₂COD)L₂]ClO₄ (Ia: L = tht, Ib: L = tms, Ic: L₂ = dth), [IrH₂(COD)-(L-L)]₂(ClO₄)₂ (IIa: L-L = tmdto, IIb: L-L = dt) and [IrH₂(CO)₂(tmdto)]₂-(ClO₄)₂ (III). The ¹H NMR chemical shifts and ν(IrH) data are discussed.     

Synthesis,Crystal Structures and Luminescent Properties of Terbium,Neodymium and Yttrium Complexes with a New Amide Type Ligand

Solid complexes of terbium, neodymium and yttrium nitrates with an amide type ligand, N‐benzyl‐2‐(benzyloxy)benzamide ( L ) have been prepared in ethyl acetate and characterized by elemental analysis and IR spectroscopy. The crystal and molecular structures of the complexes Tb L ₃(NO₃)₃, Nd L ₃(NO₃)₃ and Y L ₃(NO₃)₃ have been determined by single crystal X‐ray diffraction. The crystal structures of the complexes are similar. The structures show that the crystal consists of two similar but independent molecules in the asymmetric unit and the metal ion is coordinated toward nine donor atoms, three of which belong to the oxygen atoms of three monodentate ligands and six oxygen atoms from three bidentate nitrates. Furthermore, the RE L ₃(NO)₃ complex units are linked by the intermolecular hydrogen bonds to form a three‐dimensional net. At the same time, the luminescent properties of the ligand and the complex Tb L ₃(NO₃)₃ were studied as well.     

Synthesis and characterization of cyano complexes of oxotungsten(IV) with morpholinomethyl urea and related ligands

The synthesis and characterization of complexes, (Ph₃P)₂NH₂[WO(CN)₃L-L] · 3H₂O and Cs[WO(CN)₃L-L] · H₂O (where L-L = morpholinomethylurea, morpholinomethylthiourea, piperidinomethylurea, piperidinomethylthiourea, pyrrolidinomethylurea, and pyrrolidinomethythiourea) are presented. The complexes have been prepared by the reaction of K₃Na[WO₂(CN)₄] · 6H₂O with morpholinomethylurea and related ligands in aqueous solution around a pH of 7. These have been isolated as bis(triphenylphospine)imminium or cesium salts. The complexes have been characterized by elemental analysis, ℝ, UV-Vis spectra, magnetic susceptibility and conductivity measurements in addition to TGA/DTA The text was submitted by the authors in English.     

Reductive nitrosylation of tetraoxometallates. Part VIII1. A virtually single step synthesis of azido-nitrosyl derivatives of chromium(I) directly from chromate in aqueous-aerobic media.

Azido-nitrosyl complexes and their derivatives of the types [Cr(NO)(N₃)₅]^3? and [Cr(NO)(N₃)₂(L-L)] [L-L = 2,2′bipyridine (bipy) and 1,10 phenanthroline (phen)] were synthesised directly from chromate ion using hydroxylamine hydrochloride, azide ion and hydroxyl ion and other appropriate ligands virtually in a single step process in an aqueous aerobic medium. The compounds are characterised by IR, molecular weight, molar conductance, magnetic susceptibility, esr and electronic spectral data.     

含不同芳香取代基的肼基二硫代甲酸甲酯-Ga3+配合物的合成及抑菌活性

设计合成了4种含不同芳香取代基团的肼基二硫代甲酸甲酯配体（2-乙酰基吡啶肼基二硫代甲酸甲酯（L¹-H）、2-甲酰基吡啶肼基二硫代甲酸甲酯（L²-H）、2-甲酰基噻吩肼基二硫代甲酸甲酯（L³-H）、2-甲酰基水杨醛肼基二硫代甲酸甲酯（L⁴-H））的镓配合物,对它们的抑菌活性进行了测试,并讨论了配体分子中不同芳香取代基对配合物抑菌活性的影响。在模拟生理条件下,L与Ga³⁺生成较稳定的单核配合物[Ga（L¹）₂]NO₃（1）、[Ga（L²）₂]NO₃（2）、[Ga（L³）₂]NO₃（3）、[Ga（L⁴）₂]NO₃（4）,各配合物对金黄色葡萄球菌和大肠杆菌表现出比Ga（NO₃）₃·9H₂O强的抑制活性,抑制金黄色葡萄球菌的能力高于大肠杆菌,其中,1和2的活性比相应配体高,其余2个配合物与其配体之间无明显活性差异。L¹和L²分子中吡啶基的较强吸电子效应可能是1和2具有较强抑菌活性的主要原因。4种配合物抑制黑曲霉生长的活性同样高于Ga（NO₃）₃·9H₂O,其中3最强,并显著高于L³,其余配合物与相应配体间无活性差异。     

Synthesis, characterization, thermal stability, reactivity, and antimicrobial properties of some novel lanthanide(III) complexes of 2-(N-salicylideneamino)-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

Two series of new lanthanide(III) complexes of the type [Ln(HSAT)₂(H₂O)₃Cl₃] and [Ln(HSAT)₂(NO₃)₃], where Ln = La, Pr, Nd, Sm, Eu, Gd, Dy, Tm, Yb, or Lu, and HSAT = 2-(N-salicylideneamino)-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene, are synthesized by the reaction of LnCl₃ or Ln(NO₃)₃ with the title ligand in ethanol. The complexes are characterized by elemental analysis, magnetic moment values, molar conductivity, IR, UV-Vis, and ¹H NMR spectral data. Two selected complexes are subject to thermogravimetric analysis, and their kinetic parameters are estimated using Coats-Redfern equation. The complex [La(HSAT)₂(NO₃)₃] underwent facile transesterification when refluxed in methanol. The ligand and some selected complexes are screened for their antimicrobial properties. Antimicrobial activities of the ligand increase on coordination with the metal ion. The text was submitted by the authors in English.     

Synthesis of cationic carbonyl complexes of manganese(I) with bidentate ligands

Summary Bidentate ligands can readily replace acetone in thefac-[Mn(CO)₃(chel)(OCMe₂)]⁺ complexes or the perchlorate group fromfac-[Mn(CO)₃(chel)(OClO₃)] yieldingfac-[Mn(CO)₃(chel)(L-L)]⁺ or [{fac-Mn(CO)₃(chel)}₂(L-L)]²⁺ [chel = 1,10-phenanthroline (phen), 2,2-bipyridine (bipy), 1,2-bis(diphenylphosphine)ethane (dpe); L-L = bis(diphenylphosphine)methane (dpm), dpe, 1,4-bis(diphenylphosphine)butane (dpb), succinonitrile (suc), and glutaronitrile (glu)]. Some of these mononuclear complexes are precursors for binuclear complexes which are linked by bridging phosphines or nitriles.     

Ligating properties oftert-phosphine/arsine sulphides or selenides,Part IX. Preparation and spectroscopic studies of copper(I)/copper(II) complexes with bis(—phosphine chalcogenides)

Summary The analytical, molar conductance and spectroscopic studies of new complexes of copper(I) and copper(II) with bis(—phosphine chalcogenides), Ph₂P(E)(CH₂)_n-P(E)Ph₂(L-L) are reported. The complexes are of the types: (a) [CuX(L-L)](X, n, E: Cl, 2–4, Br, 2, S; Cl, Br, 1, Se); (b) [Cu₂X₂(L-L)] (X, n, E: Cl, Br, 2, 3, Se) and (c) [CuCl₂(L-L)] (n, E: 2, 3, S). Possible structures have been derived.     

Synthesis,crystal structure and DFT calculations of octahedral nickel(II) complexes derived from N′-[(E)-phenyl(pyridin-2-yl)methylidene]benzohydrazide

The two new nickel(II) complexes, [Ni(HL)(L)](NO₃)?H₂O (1) and [Ni(L)₂] (2) (where HL/L = N′-[(E)-phenyl(pyridin-2-yl)methylidene]benzohydrazide), have been synthesized and characterized by elemental analysis, spectroscopic, magnetic susceptibility, and cyclic voltammetric measurements. Single-crystal X-ray analysis of [Ni(HL)(L)](NO₃)?H₂O (1) and [Ni(L)₂] (2) has revealed the presence of a distorted octahedral geometry around nickel(II). The X-ray and spectral characterizations have confirmed the existence of the keto-enol form of the ligands in the complexes. The electronic structures and spectral properties of the ligands and the complexes have been explained by DFT and TDDFT calculations. Superoxide dismutase activity of these complexes has also been measured.     

Direct synthesis of six-coordinate nitro complexes of cobalt meso-tetraphenylporphyrinate with trans-O-donor ligands

The formation of a series of six-coordinate complexes (B)Co(TPP)(NO₂) (B is ketone, aldehyde, ether or epoxide; TPP is meso-tetraphenylporphyrin dianion) on exposure of thin films of five-coordinate Co(TPP)(NO₂) to vapors of the O-donor ligands was established by IR and UV/Vis spectroscopy (resorting to the data on isotope-substituted ¹⁵NO₂). The complex formation is accompanied by shifts of the vibration frequencies of the trans-NO₂ ligand and gives rise to new IR bands corresponding to the O-donors in the ν(C=O) or ν(C-O) region shifted with respect to these bands of free ligands. The complexes are rather stable in the solid phase but eliminate the O-donor ligand upon dissolution in an inert solvent (or upon maintenance in a vacuum for some complexes) being converted into the initial five-coordinate nitro complex. Using the IR spectra of CCl₄ solutions of the complexes containing a large excess of O-donor molecules, the equilibrium constants and the formation enthalpies of some (B)Co(TPP)(NO₂) complexes were determined, indicating weak coordination of these ligands.     

Synthesis and application of a new copper(II) complex containing oflx and leof

Two new copper(II) complexes of [Cu(Ofloxacin)(phen)(H₂O)] · (NO₃) · 2H₂O and [Cu(Levofloxacin)(phen)(H₂O)] · (NO₃) · 2H₂O were obtained and their structures were studies. Both ligands and complexes were assayed against gram-positive and gram-negative bacteria by the in vitro doubling dilutions method. The inhibitory effect of the ligands and complexes on the leukemia HL-60 cell line were measured with the MTT assay method and the liver cancer HePG-2 cell line measured by the SRB method. The results indicated that the complexes have stronger inhibitory effect on HL-60 than on HePG-2. The complex [Cu(Levofloxacin)(phen)(H₂O)] · (NO₃) · 2H₂O (I) has stronger effect on HL-60 than the complex (Cu(Ofloxacin)(phen)(H₂O)] · (NO₃) · 2H₂O (II). The text was submitted by the authors in English.     

Cerium(IV) Nitrate Complexes With Bidentate Phosphine Oxides

The reactions between ceric ammonium nitrate, (NH₄)₂Ce(NO₃)₆, (CAN) and the bidentate phosphine oxides, 4,5-bis(diphenylphosphine oxide)-9,9-dimethylxanthene (L¹), oxydi-2,1-phenylene bis(diphenylphosphine dioxide) (L²), 1,2-bis(diphenylphosphino)ethane dioxide (L³) and 1,4-bis(diphenylphosphino)butane dioxide, L⁴ have been investigated. The crystal structures of the molecular Ce(NO₃)₄L¹ ( 1 ), and ionic [Ce(NO₃)₃L³₂][NO₃]⋅CHCl₃ ( 3 ), [Ce(NO₃)₃L³₂][NO₃] ( 4 ) and the polymeric [Ce(NO₃)₃L⁴_1.5] [NO₃] ( 5 ) and the cerium(III) complex [Ce(NO₃)₂L¹₂][NO₃] ( 2 ) are reported. The thermal stability of the complexes has been examined by thermogravimetry with the gaseous decomposition products analysed by infrared spectroscopy. Evolution of CO₂ is found for both Ce(III) and Ce(IV) complexes with the later also forming NO₂. The formation of the complexes in solution has been studied by ³¹P NMR spectroscopy and further complexes [Ce(NO₃)₃L¹₂]⁺[NO₃]⁻ and [Ce(NO₃)₂L¹₃]²⁺2[NO₃]⁻ identified in CD₃CN solution. The complex ( 1 ) exists as a single molecular species in solution and is stable in dichloromethane whilst ( 3 ) decomposes on standing in both CD₂Cl₂ and CD₃CN to Ce(III) containing species. Complexes of L² have been identified by solution ³¹P NMR spectroscopy and these decompose in solution to give Ce(NO₃)₃L²₂. This study represents the first structural characterisations of Ce(IV) complexes with bidentate phosphine oxides.