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1.
The thermal decomposition of copper(II) complexes with salicylaldehyde S-methylthiosemicarbazone of general formula Cu(HL)X·nH2O (X=Py+NO3, NCS, 0.5SO4) and [Cu(L)NH3]·H2O was investigated in air atmosphere in the interval from room temperature to 1000°C. Decomposition of the complexes occurred in several successive endothermic and exothermic processes, and the residue was in all cases CuO.  相似文献   

2.
New complexes of 2-benzoyl-pyridil-isonicotinoylhydrazone (L) with Cu(II), Co(II), Ni(II) and Mn(II), having formula of type [ML2] SO4·xH2O (M = Cu2+, Co2+, Ni2+, x = 2 and M = Mn2+, x = 3), have been synthesised and characterised. All complexes were characterised on the basis of elemental analyses, IR spectroscopy, UV–VIS–NIR, EPR, as well as thermal analysis and determination of molar conductivity and magnetic moments. The thermal behaviour of complexes was studied using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The structure of L hydrazone was established by X-ray study on single crystal. The ligand works as tridentate NNO, being coordinated through the azomethine nitrogen, the pyridine nitrogen and carbonylic oxygen. Heats of decomposition, ΔH, associated with the exothermal effects were also determined.  相似文献   

3.
New mixed ligand complexes of the following stoichiometric formulae: M(2-bpy)2(RCOO)2·nH2O, M(4-bpy)(RCOO)2·H2O and M(2,4’-bpy)2(RCOO)2·H2O (where M(II)=Zn, Cd; 2-bpy=2,2’-bipyridine, 4-bpy=4,4′-bipyridine, 2,4′-bpy=2,4′-bipyridine; R=C2H5; n=2 or 4) were prepared in pure solid-state. These complexes were characterized by chemical and elemental analysis, IR and conductivity studies. Thermal behaviour of compounds was studied by means of DTA, DTG, TG techniques under static conditions in air. The final products of pyrolysis of Cd(II) and Zn(II) compounds were metal oxides MO. A coupled TG/MS system was used to analyse of principal volatile products of thermal decomposition or fragmentation of Zn(4-bpy)(RCOO)2·H2O under dynamic air and argon atmosphere. The principal species correspond to: C+, CH+, CH3 +, C2H2 +, HCN+, C2H5 + or CHO+, CH2O+ or NO+, CO2 +, 13C16O2 + and 12C16O18O+ and others; additionally CO+ in argon atmosphere.  相似文献   

4.
Four new dinuclear complexes of the type [M2(cyclen)2(suc)]Cl2 · nH2O (M = Co2+, Ni2+, Cu2+, Zn2+, cyclen = 1,4,7,10-tetraazacyclododecane, suc = succinate) have been obtained by the reaction of cyclen and succinate with the corresponding metal dichlorides in aqueous solution. All the complexes were characterized by physico-chemical and spectroscopic methods. The crystal structure of [Ni2(cyclen)2(suc)]Cl2 · 2H2O was determined. The four complexes have similar compositions and structures and are all bridged by succinate. Furthermore, the hydrolysis of bis(2,4-dinitrophenyl)phosphate (BDNPP) promoted by the four complexes was studied. The experimental results indicate that these complexes can efficiently catalyze hydrolysis of BDNPP, and their catalytic activities are in the order Ni > Zn > Cu > Co.  相似文献   

5.
Complexes of Co2+, Ni2+, and Cu2+ with N-(phosphonomethyl)aminosuccinic acid (H4PMAS) of general formula Na2MPMAS·nH2O [M=Co(II), Ni(II), Cu(II), n—number of water molecules] were synthesized. Based on interpretation of diffusion reflectance spectroscopy, structure of all complexes is based on distorted octahedral. Analysis of IR spectra of Co(II), Ni(II), and Cu(II) N-(phosphonomethyl)aminosuccinates demonstrated that metal ions are coordinated to the ligand through nitrogen atom of the imino group, oxygen atoms of the α- and β-carboxyl groups as well as oxygen atom of the phosphonic group of the H4PMAS. We demonstrated that thermal stability of complexes increases in sequence Cu(II) < Ni(II) < Co(II), obviously as a result of change over from the dimeric to polymeric character of the initial complex. Complete decomposition of ligand occurs at these temperatures and is accompanied by release of H2O, CO2, and NO2. The final products of thermal decomposition of the complexes are mixtures of oxides and phosphates of respective metals.  相似文献   

6.
By diffusion in gel medium new complexes of formulae: Nd(btc)⋅6H2O, Gd(btc)⋅4.5H2O and Er(btc)·5H2O (where btc=(C6H3(COO)3 3−) were obtained. Isomorphous compounds were crystallized in the form of globules. During heating in air atmosphere they lose stepwise water molecules and then anhydrous complexes decompose to oxides. Hydrothermally synthesized polycrystalline lanthanide trimellitates form two groups of isomorphous compounds. The light lanthanides form very stable compounds of the formula Ln(btc)⋅nH2O (where Ln=Ce−Gd and n=0 for Ce; n=1 for Gd; n=1.5 for La, Pr, Nd; n=2 for Eu, Sm). They dehydrate above 250°C and then immediately decomposition process occurs. Heavy lanthanides form complexes of formula Ln(btc)⋅nH2O (Ln=Dy−Lu). For mostly complexes, dehydration occurs in one step forming stable in wide range temperature compounds. As the final products of thermal decomposition lanthanide oxides are formed.  相似文献   

7.
The new mixed ligand complexes with formulae M(4-bpy)(C2H5COO)2·2H2O (where M(II)=Mn, Co, Ni; 4,4'-bpy or 4-bpy=4,4'-bipyridine) and Cu(4-bpy)0.5(C2H5COO)2·H2O were prepared and characterized by VIS (for solid compounds of Co(II), Ni(II), Cu(II) in Nujol), IR spectroscopy, X-ray powder diffraction and molar conductance in MeOH, DMF or DMSO. Thermal behaviour of complexes was studied under static conditions in air atmosphere. Corresponding metal oxides were identified as final products of pyrolysis. A coupled TG-MS system was used to analysis of principal volatile thermal decomposition and fragmentation products of isolated complexes under dynamic air and argon atmosphere. The principal species correspond to: C+, OH+, H2O+, NO+, CO2 + and other; additionally CO+ in argon atmosphere. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
Two new ligands, 4-hydroxy coumarin-3-thiosemicarbazone (H2L1) and 4-hydroxy coumarin-3-semicarbazone (H2L2) were synthesized and used for the preparation of a series of transition metal complexes (Cr3+, Co2+, Ni2+, Cu2+, and Fe3+), derived from these ligands. These complexes have the forms [ML1Cl2nX (15) and [ML2Cl]·nX (69) (X = H2O or ethanol). The structures of these complexes were elucidated by elemental analyses, IR, UV–Vis, and electrical conductivity, as well as magnetic susceptibility measurements and thermal analyses. IR spectral data indicates that in all complexes, the ligands act as monobasic tridentate, coordinated through keto oxygen or sulfur, azomethine nitrogen and deprotonated phenolic oxygen atom. On the basis of other physicochemical investigations, tetrahedral or square planar geometries are assigned for Cu2+ complexes in monomeric structures. In the case of the Co2+, Ni2+ and Fe3+ complexes, octahedral stereochemistries in monomeric structures are suggested. The dissociation constants of the ligands and the stability constants of their Cu(II), Co(II), Ni(II), and Fe(III) complexes have been also determined using potentiometric pH-metric titration in mixed solvents of dioxane: H2O and DMF: H2O with different ratios and different temperatures.  相似文献   

9.
The reactions of 2-(2-pyridyl)benzothiazole (1) with MX2·nH2O salts (M = NiII, CoII, or CuII; X = Cl or ClO4; n = 0–2) in EtOH afforded the corresponding complexes. Depending on the nature of the counterion in the starting metal salt, the reactions give compounds of composition M(1)Cl2·nH2O or Cu(1)2(ClO4)2·H2O. The molecular and crystal structure of the CuII(1)2(ClO4)2·H2O complex was established by X-ray diffraction. The copper atom in this complex has a distorted tetragonal-pyramidal ligand environment and is coordinated by four nitrogen atoms of two ligand molecules and one water molecule. Electrochemical study of the ligand and the resulting complexes by cyclic voltammetry and at a rotating disk electrode demonstrated that ligand 1 stabilizes reduced forms of complexes containing Ni, Co, or Cu atoms in the oxidation state +1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1738–1744, October, 2006.  相似文献   

10.
The complexes of 4-chloro-2-methoxybenzoic acid anion with Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ were obtained as polycrystalline solids with general formula M(C8H6ClO3)2·nH2O and colours typical for M(II) ions (Mn – slightly pink, Co – pink, Ni – slightly green, Cu – turquoise and Zn – white). The results of elemental, thermal and spectral analyses suggest that compounds of Mn(II), Cu(II) and Zn(II) are tetrahydrates whereas those of Co(II) and Ni(II) are pentahydrates. The carboxylate groups in these complexes are monodentate. The hydrates of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) heated in air to 1273 K are dehydrated in one step in the range of 323–411 K and form anhydrous salts which next in the range of 433–1212 K are decomposed to the following oxides: Mn3O4, CoO, NiO and ZnO. The final products of decomposition of Cu(II) complex are CuO and Cu. The solubility value in water at 293 K for all complexes is in the order of 10–3 mol dm–3. The plots of χM vs. temperature of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) follow the Curie–Weiss law. The magnetic moment values of Mn2+, Co2+, Ni2+ and Cu2+ ions in these complexes were determined in the range of 76−303 K and they change from: 5.88–6.04 μB for Mn(C8H6ClO3)2·4H2O, 3.96–4.75 μB for Co(C8H6ClO3)2·5H2O, 2.32–3.02 μB for Ni(C8H6ClO3)2·5H2O and 1.77–1.94 μB for Cu(C8H6ClO3)2·4H2O.  相似文献   

11.
Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 3-methoxy-4-methylbenzoates were investigated and their quantitative composition and magnetic moments were determined. The IR spectra and powder diffraction patterns of the complexes prepared of general formula M(C9H9O3)2·nH2O (n=2 for Mn, Co n=1 for Ni, Cu, n=0 for Zn, Cd) were prepared and their thermal decomposition in air was studied. Their solubility in water at 293 K is of the order 10–2 (Mn)–10–4 (Cu) mol dm–3. IR spectra of the prepared 3-methoxy-4-methylbenzoates suggest that carboxylate groups are bidentate bridging. The magnetic moments for the paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II) attain values 5.50, 4.45, 3.16 and 1.79 B. M., respectively. During heating the hydrated complexes lose crystallization water molecules in one step and then the anhydrous complexes decompose directly to oxides MO and Mn3O4. Only Co(II) complex decomposes to Co3O4 with intermediate formation CoO.  相似文献   

12.
New Co(II), Ni(II), and Cu(II) complexes with 4-(3-hydroxyphenyl)-1,2,4-triazole (L) with the compositions [Co3L6(H2O)5(C2H5OH)](NO3)6 · 2H2O · C2H5OH (I), [Ni3L6(H2O)6](NO3)6 · 2H2O (II), and [M3L6(H2O)6](ClO4)6 · nH2O (M = Co2+, n = 2 (III); Ni2+, n = 2 (IV); Cu2+, n = 0 (V)) are synthesized. The complexes are studied by X-ray structure analysis, X-ray diffraction analysis, UV and IR spectroscopy, and the statistical magnetic susceptibility method. All compounds have the linear trinuclear structure. Ligand L is coordinated to the metal ions by the N(1) and N(2) atoms of the heterocycle according to the bidentate bridging mode. In all compounds the coordination polyhedron of the metal atom is a distorted octahedron. The molecular and crystal structures of compound I, [Co3L6(H2O)6](ClO4)6 · 8C2H5OH (IIIa), and [Ni3L6(H2O)6](ClO4)6 · 8C2H5OH (IVa) are determined.  相似文献   

13.
4,6-Diacetylresorcinol serves as a starting point for the generation of multidentate S/N/O or O/N/O symmetrical chelating agents by condensation with thiosemicarbazide or semicarbazide to yield the corresponding bis(thiosemicarbazone) H4L1 or bis(semicarbazone) H4L2, respectively. Reaction of H4L1 and H4L2 with M(NO3)2·6H2O (M?=?Co or Ni) afforded dimeric complexes for H4L1 and binuclear complexes for H4L2, revealing the tendency of S to form bridges. The dimeric cobalt complexes of H4L1 are very interesting in that they contain CoII/CoIII, side/side, low-spin octahedral coordinated CoIII-ions and high-spin square-planar coordinated CoII-ions. These complexes have the general formula [(H2L1)2Co2(H2O) (NO3)]·nEtOH. Arguments supporting these anomalous CoII/CoIII structures are based on a pronounced decrease in their magnetic moments, elemental and thermal analyses, visible and IR spectra, as well as their unreactivity towards organic bases such as 1,10-phenanthroline (phen), 2,2′-bipyridine (Bpy), N,N,N′,N′-tetramethylethylenediamine (Tmen) and 8-hydroxyquinoline (oxine, Ox). The dimeric octahedral NiII complex [(H2L1)2Ni2(H2O)4]·3H2O showed higher reactivity towards phen and Bpy and formed adducts; [(HL1)Ni2(B)(H2O)5] NO3 (B?=?phen or Bpy). In the presence of oxine, the dimeric brown paramagnetic octahedral complex [(H2L1)2Ni2(H2O)4]·3H2O was transformed to the dimeric brick-red diamagnetic square-planar complex [(H3L1)2Ni2](NO3)2. The latter showed dramatic behavior in its 1H NMR spectrum in DMSO-d 6, which was explained on the basis of H+-transfer. By contrast, the binuclear NiII–H4L2 complex (11) showed higher reactivity towards phen, Bpy and oxine. These reactions afforded mixed dimeric complexes having the molar ratio 2?:?2?:?1 (NiII?:?H4L2?:?base). The binuclear CoII–H4L2 complex afforded an adduct with phen and trinuclear complexes with Bpy and oxine. All complexes were found to be unreactive towards Tmen. Structural characterization was achieved by elemental and thermal analyses, spectral data (electronic, IR, mass and 1H NMR spectra) and conductivity and magnetic susceptibility measurements.  相似文献   

14.
New complexes of type [Cu(HTBG)2]Cl2 (1), [Cu(TBG)2]·3H2O (2) and [CuL]·nH2O (3) L:L1, n = 2 and (4) L:L2, n = 1 (HTBG: 2-tolylbiguanide, L1 and L2: ligands resulted from 2-tolylbiguanide, ammonia/hydrazine and formaldehyde one pot condensation) were synthesised and characterised. The features of complexes have been assigned from microanalytical, IR and UV–Vis data. Redox behaviour was established by cyclic voltammetry. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against Gram-negative and Gram-positive strains isolated from the hospital environment. The thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them. After water elimination, complexes have a similar thermal behaviour. Processes as water elimination, melting, chloride anion removal as well as oxidative degradation of the organic ligands were observed. The final product of decomposition was copper (II) oxide.  相似文献   

15.
A series of LnIII–SrII heterometallic coordination polymers formulated as [Ln2Sr3(pda)6(H2O)18]·nH2O (Ln = Pr-1, n = 14; Nd-2, n = 12; Sm-3, n = 11; Eu-4, n = 11; Gd-5, n = 16; Tb-6, n = 13; Dy-7, n = 13) were synthesized via assembly of Ln(NO3)3·6H2O, SrCl2·6H2O, pyridine-2,6-dicarboxylic acid (H2pda) and imidazole (im) in H2O/C2H5OH solution. Single crystal X-ray diffraction revealed that they are isostructural. All of these complexes possess ladder-shaped 1-D chain structures. The luminescent properties of Sm-3, Eu-4, Gd-5, Tb-6 and Dy-7 have been investigated. The solid-state quantum yields and the lifetimes of Eu-4 and Tb-6 are also studied.  相似文献   

16.
Five complexes [Co3(Hpmad)6]·(4‐sb)2·(CH3COO)2·(H2O)2 ( 1 ), [Co3(Hpmad)6]·(3‐sb)2·(CH3COO)2·(H2O)0.5 ( 2 ), [Co(Hpmad)2(4‐sb)]n ( 3 ), [Co(Hpmad)2(3‐sb)]n ( 4 ) and {[Co(Hpmad)(SO4)(H2O)2]·H2O}n ( 5 ) [Hpmad is 2‐pyrimidineamidoxime, H2(4‐sb) is 4‐sulfobenzoic acid and H2(3‐sb) is 3‐sulfobenzoic acid], were prepared at room temperature. Complexes 1 – 5 were characterized by elemental analyses, single crystal X‐ray diffractions, powder X‐ray diffractions, infrared spectra, thermogravimetric analyses, fluorescence spectra and magnetic susceptibility measurements. Complexes 1 and 2 possess the linear trinuclear Co2+ structures. Complexes 3 and 4 exhibit similar one‐dimensional (1D) chains. Complex 5 comprises the 1D helical chain. The change of anion in cobalt salt from CH3COO? to Cl? to SO42? leads to the structural evolution from the linear trinuclear Co2+ structure to the 1D chain to the 1D helical chain. Complexes 1 – 5 exhibit the Hpmad‐based emissions. The magnetic properties of 1–5 were also investigated.  相似文献   

17.
Four metal complexes of N,N′-bis(salicyl)-2,6-pyridine-dicarbohydrazide ligand (H6L), [CoII(H4L)(H2O)2]·2DMF (1), [ZnII(H4L)(H2O)2]·2DMF (2), [CdII(H4L)(Py)2]·DMF·Py (3), and [CoIICo2III(H4L)4(H2O)4]·DMF·H2O (4), were synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction analysis. Structural studies revealed that complexes 13 present discrete mononuclear structures and complex 4 displays a centrosymmetric mixed-valence trinuclear structure. All four complexes are further extended into interesting two- or three-dimensional supramolecular frameworks. The luminescent properties of 2 and 3 were studied, which show emissions with maxima at 485 nm upon excitation at 396 nm for 2 and 476 nm upon excitation at 397 nm for 3, respectively.  相似文献   

18.
Poly[triaqua‐μ4‐fumarato‐cobalt(II)], [Co(C4H2O4)(H2O)3]n, (I), contains two symmetry‐independent octahedrally coordinated Co2+ ions, both on inversion centers. One Co2+ ion is coordinated by two water molecules and four fumarate dianions, whereas the other Co2+ ion is surrounded by four water molecules and two fumarate dianions. Each fumarate dianion is bonded to three Co2+ ions, leading to a two‐dimensional structure. The fumarate dianions are nonplanar; the angle between the planes of the two carboxylate groups is 54.9 (2)°. The cobalt(II) fumarate layers are connected by hydrogen bonding into a three‐dimensional network. Compound (I) is not isostructural with calcium(II) fumarate trihydrate [Gupta et al. (1972). Acta Cryst. B 28 , 135–139]. In poly[μ4‐fumarato‐dimethanolcobalt(II)], [Co(C4H2O4)(CH4O)2]n, (II), the Co2+ ions are octahedrally coordinated by four fumarate dianions and two methanol molecules, leading to a three‐dimensional structure. The fumarate group is planar. The Co2+ ions and the fumarate dianions both lie on inversion centers. Additionally, the one‐dimensional structure of catena‐poly[[[tetraaquacobalt(II)]‐μ2‐fumarato] monohydrate], {[Co(C4H2O4)(H2O)4]·H2O}n, (III), was redetermined at a higher resolution, and the space group C2/c was confirmed.  相似文献   

19.
Alkylferrocene‐based burning‐rate catalysts (BRCs) exhibit distinct migration tendency and high volatility and thus result in inferior performance of composite solid propellants during their combustion processes. To deal with these drawbacks, a novel dinuclear nitrogen‐rich ferrocene derivative, 4‐amino‐3,5‐bis(4‐ferrocenyl‐1,2,3‐triazolyl‐1‐methyl)‐1,2,4‐triazole (BFcTAZ) and its twenty seven ionic coordination compounds, [M2(BFcTAZ)2(H2O)4]mXn·xH2O (M = Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Pb2; X = polycyano anions), were synthesized and characterized by FT‐IR, UV/Vis, and elementary analysis. Crystal structure of BFcTAZ was further confirmed by single‐crystal X‐ray diffraction and a general molecular structure of the new complexes was proposed. Their high thermal stability was verified by TG technique. Cyclic voltammetry studies suggested that the new compounds are diverse redox systems. Their effects on the thermal degradation of some common oxidizers were measured by DSC technique. The results indicated that most of the new complexes exert great effects on the thermal decomposition of AP, RDX, and 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7) and some of them are more active than catocene. The Cu2+ complexes are among the excellent ones. However, only six compounds have appreciable catalytic activity in the thermal degradation of HMX.  相似文献   

20.
Summary Metal complexes of general formula [M(DDE)·nH2O]· nH2O and [M(DDB)·nH2O] [where M = CoII, NiII, CuII, PdII and UO 2 2+ ; n = 0–4; DDE and DDB are the anion of bis(1,2-diphenyl-1-hydroxyimino-2-ethylidine)-1,2-diaminoethane and bis(l,2-diphenyl-l-hydroxy-imino-2-ethylidine)-1,4-diaminobenzene, respectively] were prepared and characterized by i.r. electromagnetic and n.m.r. spectroscopy and magnetic measurements.  相似文献   

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