Soft template synthesis of (2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9) nickel(II) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8)nickel(II) using a nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix

Complexing processes leading under specific conditions to nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix systems in contact with aqueous-alkaline solutions (pH12) containing dithiooxamide and formaldehyde or glyoxal, have been studied. It has been shown that template synthesis of macrocyclic co-ordination compounds, (2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9)nickel(II) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8)nickel(II), occurs. Dithiooxamide, formaldehyde and glyoxal act as ligand synthons in this process.     

Soft template synthesis of macrocyclic copper(II) chelates with 3,9-dithio-4,8-diaza-6-oxaundekandithioamide-1,11 in a Cu2[Fe(CN)6]-gelatin-immobilized matrix

The complexing processes in the triple copper(II)–dithiomalonamide–methanal system taking place in the copper(II)hexacyanoferrate(II)-gelatin-immobilized matrix in contact with aqueous alkaline solutions (pH12), containing dithiomalonamide and methanal, have been studied. Template synthesis leading to a macrocyclic coordination compound with the tetradentate N,N,S,S-donor ligand, (3,9-dithio-4,8-diaza-6-oxaundekandithioamide-1,11), occurs under these specific conditions when dithiomalonamide and methanal are the ligand synthons.     

Cobalt(III)-8-mercaptoquinoline complexing in cobalt(III)hexacyanoferrate(II) gelatin-immobilized matrix systems

Novel complexing processes in binary systems containing Co^III and 8-mercaptoquinoline or its derivatives (5-Cl-, 5-Br-, 5-Me-, 5-Ph- and 5-SMe- 8-mercaptoquinoline), with a cobalt(III)hexacyanoferrate(II) gelatin-immobilized matrix in contact with an aqueous solution of the corresponding ligand, have been observed. Under the specific conditions described, three water-insoluble coordination compounds are formed in each of the systems indicated, whereas upon complexing in solution or the solid phase the formation of only one complex is observed.     

Cobalt(II)-8-mercaptoquinolines complexing in cobalt(II) hexacyanoferrate(II) gelatin-immobilized matrix materials

Complexing processes between Co^II and 8-mercaptoquinoline, or its various alkyl- and aryl-substituted derivatives, in contact with Co₂[Fe(CN)₆]-gelatin-immobilized matrix materials, with aqueous solutions of corresponding ligands, have been studied. When R² = Me or Ph, formation of Co^II chelates having a 1:2 metal ion/singly deprotonated ligand is observed, whereas when R² = H, formation of Co^III chelates having metal ion/singly deprotonated ligand 1:3 ratios occur.     

Mild template synthesis of a copper(II)-containing macrocyclic compound with 4,4,6-trimethyl-2,3,7,8-tetraazanonen-6-dithiohydrazide-1,9 in a gelatin-immobilized matrix

The complexing processes in the triple copper(II)–thiocarbohydrazide–propanone system taking place in a copper(II) hexacyanoferrate(II) gelatin-immobilized matrix in contact with aqueous-alkaline solutions (pH12), containing thiocarbohydrazide and propanone, have been studied. Template synthesis leading to a macrocyclic coordination compound with the tetradentate N,N,S,S-donor ligand, (4,4,6-trimethyl-2,3,7,8-tetraazanonen-6-dithiohydrazide-1,9), occurs under these specific conditions when thiocarbohydrazide and propanone are the ligand synthons.     

Complexing of nickel(II) with 8-mercaptoquinoline and of its 5-derivatives in nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix systems

Complexing processes in systems containing NiII and 8-mercaptoquinoline or its derivatives (5-chloro-, 5-bromo-, 5-phenyl, 5-thiomethyl-8-mercaptoquinoline and 5,8-dimercaptoquinoline) take place in the nick- el(II)hexacyanoferrate(II) gelatin-immobilized matrix (GIM) in contact with an aqueous solution of the corresponding ligand. Under the conditions specified, in the NiII-8-mercaptoquinoline, NiII-5-chloro-8-mer captoquinoline,NiII-5-bromo-8-mercaptoquinoline, NiII-5-phenyl-8-mercaptoquinoline and NiII-5-thiomethyl-8-mercaptoquinoline systems, one water-insoluble complex of NiB2 composition (B– is a singly deprotonated ligand) is formed. In the NiII-5,8-dimercaptoquinoline system, two insoluble complexes, monomeric Ni(HB)2 and polymeric [Ni2B2(H2O)2]n (HB– is the singly, and B2– the doubly deprotonated form of the ligands) are generated. Upon complexing in solution or the solid phase, the formation of only one complex is observed in each of systems cited.     

Molecular structures of macrotricyclic 4<Emphasis Type="Italic">d</Emphasis> M(II) chelates with the (NNNN)-donor ligand 2,7-dithio-3,6-diazaoctadiene-3,5-dithioamide-1,8 according to quantum-chemical density functional theory calculations

The thermodynamic and geometric parameters of the molecular structures of macrotricyclic Mo(II), Ru(II), Rh(II), Pd(II), Ag(II), and Cd(II) complexes with the tetradentate ligand 2,7-dithio-3,6-diazaoctadiene-3,5-dithioamide-1,8 with the (NNNN) coordination of the donor centers have been calculated by the hybrid density functional theory (DFT) method in the OPBE/TZVPQZP approximation with the use of the Gaussian09 program package. The Pd(II), Ag(II), and Cd(II) complexes are exactly planar, the Tc(II) and Rh(II) complexes exhibit slight deviations from coplanarity, while the Mo(II) and Ru(II) complexes have rather significant deviations. The five-membered chelate rings in the complexes are either strictly planar or deviate slightly (no more than by 5°) from coplanarity.     

Complexing processes in M(II)-dithiomalonamide-diacetyl triple systems (M= Ni,Cu) in ethanol solution and in a metal(II)hexacyanoferrate(II) gelatin-immobilized matrix materials

The complexing processes in the M ^II -dithiomalonamide-diacetyl triple system (M=Ni, Cu) occuring in the nickel(II)- and copper(II)hexacyanoferrate(II) gelatin-immobilized matrix in contact with aqueous alkaline solutions (pH~12) containing dithiomalonamide and diacetyl at room temperature, and between MCl₂, dithiomalonamide and diacetyl in EtOH solutions upon heating to$80°C, have been studied. In the Ni ^II -dithiomalonamide-diacetyl system, template synthesis occurs in EtOH solution but does not occur in the gelatin-immobilized matrix, whereas in the Cu ^II -dithiomalonamide-diacetyl system, template synthesis occurs in the gelatin-immobilized matrix but not in EtOH solution. Dithiomalonamide and diacetyl are the ligand synthons in the processes indicated.     

Kinetics and mechanism of reduction of 2,8-dimethyl-1,9-diphenyl-3,7-diaza-2,7-nonadiene-1,9-dione dioximatocopper(III) ([CuIII A]+) and 4,6,9-trimethyl-5,8-diaza-4,8-dodecadiene-2,3,10,11-tetraone 3,10-dioximatocopper(III) ([CuIIIB]+) by p-methoxyphenol, 1,2-dihydroxybenzene, 1,4-dihydroxybenzene and some of its derivatives

The kinetics of reduction of two copper(III)-imine-oxime complexes, [Cu^IIIA]⁺ and [Cu^IIIB]⁺, (H₂A and H₂B=2,8-dimethyl-1,9-diphenyl-3,7-nonadiene-1,9-dione dioxime and 4,6,9-trimethyl-5,8-diaza-4,8-dodecadiene-2,3,10,11-tetraone 3,10-dioxime respectively) by hydroquinone (H₂Q), 2-methylhydroquinone (MH₂Q), 2-chlorohydroquinone (ClH₂Q), catechol (H₂Cat) and p-methoxyphenol (pMHP) have been examined in aqueous acidic solution. Under fixed reaction conditions, the kinetics display first-order dependence on each oxidant and reductant. The pH-dependence is complex for the reduction of [Cu^IIIA]⁺, since both the copper(III) complex and the reductants undergo protonation–deprotonation equilibria. In the lower pH range, the second-order rate constant, k ₂, decreases with increasing pH. In the higher pH range, k ₂ increases with increasing pH. In the lower pH range the most important oxidant is [Cu^IIIHA]²⁺, whereas, in the higher pH range the most important reactants are deprotonated reductants. However for H₂Cat, as was observed before, two reaction pathways seem to operate in the high pH range. In one pathway, HCat^? seems to be involved; whereas, in the other pathway Cat^2? seems to be the reactive species. Doubly deprotonated catechol, Cat^2?, is very unlikely to be formed at pH ≤ 5. It was therefore necessary to invoke a strong interaction between [Cu^IIIA]⁺ and HCat^? followed by loss of the second proton. The pH dependence for the reduction of [Cu^IIIB]⁺ is less complex. Thus H₂Q and MH₂Q showed no pH dependence up to pH ～ 4.60, whereas ClH₂Q, pMHP and H₂Cat displayed an inverse first-order dependence on [H⁺]. Observed rate constants showing first-order dependence and inverse first-order dependence on [H⁺] correlate reasonably well with those calculated using the Marcus equation. The reaction path involving Cat^2? is believed to proceed by an inner-sphere mechanism. The agreement between the calculated and observed values for the [Cu^IIIA]⁺ complex is lower than was found for the [Cu^IIIA₁]⁺(A₁=3,9-diethyl-4,8-diaza-3,8-undeca-2,10-dionedioxime). It seems that the replacement of methyl groups in the latter complex by phenyl groups in the former complex causes both electronic and steric effects, and both effects seem to retard electron transfer. The electronic effect is readily seen in the decrease of the reduction potential of [Cu^IIIA]⁺ (E ⁰=1.09 V) compared to the reduction potential of [Cu^IIIA₁]⁺(E ⁰=1.16 V) and thus making the former a weaker oxidant. The self-exchange rate constant (5 × 10⁵ M ^?1 s^?1) estimated for complexes with type H₂A ligands seem to work well for complexes with type H₂B ligands. This situation is supported by the findings of a fairly constant value for the self-exchange rate constant for Cu ^III/II –peptide complexes with varying substituents.     

Mild template synthesis in the iron(III)-ethanedithioamide-1,2-formaldehyde triple system on a K[Fe2(CN)6] gelatin-immobilized matrix

Complexation of Fe^III, in the form of K[Fe₂(CN)₆] gelatin-immobilized matrix, in contact with aqueous-alkaline solutions (pH ～ 12) containing ethanedithioamide-1,2 and formaldehyde, has been studied. Template synthesis leading to a chelate Fe^III coordination compound with a tetradentate N,N,S,S-donor ligand identified as 4,4,6-trimethyl-1,9-diamino-1,9-dimercapto-3,7-diazanon-3-en-2,8-dithione and hydroxy co-ligand occurs under these specific conditions. Ethanedithioamide-1,2 and formaldehyde are the ligand synthons in the process studied.     

Iron(II)-8-mercaptoquinoline,iron(II)-5-chloro-8-mercaptoquino-line and iron(II)-5-bromo-8-mercaptoquinoline complexing in the iron(III) hexacyanoferrate(II) gelatin-immobilized matrix systems

Novel complexing processes in the Fe^II-8-mercaptoquinoline, Fe^II-5-chloro-8-mercaptoquinoline and Fe^II-5-bromo-8-mercaptoquinoline systems, not used previously in coordination chemistry, namely complexing as an iron(III)hexacyanoferrate(II) gelatin-immobilized matrix (GIM) in contact with an aqueous solution of the corresponding ligand, have been observed and analysed. Incorporation of these ligands into the inner coordination sphere is preceded by the decomposition of the immobilized compound KFe[Fe(CN)₆] to form hydroxides or oxohydroxides of Fe^II and Fe^III under the action of OH^- ions. It has been shown that Fe^IIFeIII redox process and the formation of FeB₃ chelates (B^- is a singly deprotonated form of the corresponding ligand) take place during complexing under such conditions.     

Iron(III), cobalt(II,III), copper(II) and zinc(II) complexes of 2-pyridineformamide 3-piperidylthiosemicarbazone

Reduction of 2-cyanopyridine by sodium in the presence of 3-piperidylthiosemicarbazide produces 2-pyridineformamide 3-piperidylthiosemicarbazone, HAmpip. Complexes with iron(III), cobalt(II,III) copper(II) and zinc(II) have been prepared and characterized by molar conductivities, magnetic susceptibilities and spectroscopic techniques. In addition, the crystal structures of HAmpip, [Fe(Ampip)₂]ClO₄, [Cu(HAmpip)Cl₂]·CH₃OH and [Zn(HAmpip)Br₂]·C₂H₆SO have been determined. Coordination is via the pyridyl nitrogen, imine nitrogen and thiolato or thione sulfur when coordinating as the anionic or neutral ligand, respectively.     

Determination of cysteine, 3-mercaptopropionic, and mercaptosuccinic acid with neutral hexacyanoferrate(III)

Two procedures are proposed for the determination of -SH groups. In both a known amount of hexacyanoferrate(III) is added to the sample and the excess is then determined. In one procedure an excess of ascorbic acid is added and the excess of that is titrated with iodine. In the other, the excess is determined by direct titration with ascorbic acid. Both procedures avoid errors resulting from side-reactions of iodine which takes place if the excess of hexacyariofcrrate(III) is reacted with potassium iodide.     

Convenient synthesis of 2-(2-pyridyl)-1, 3-diaminopropane,and its copper(II), nickel(II), and cobalt(III) complexes

Summary 2-(2-Pyridyl)-1, 3-propanediol was converted into the diacetate, which was then condensed with phthalimide. The product was hydrolyzed with hydrochloric acid to give 2-(2-pyridyl)-1, 3-diaminopropane. The free amine gave 12 complexes with copper(II), nickel(II), and cobalt(III), which were characterized spectroscopically and magnetically. Features of the amine as a ligand are discussed. A few related complexes were also studied.     

Synthesis and NMR Characterization of Cobalt(III) Complexes with 1,8-diamino-3,6-dithiaoctane, 2,2-Bipyridine,and 1,10-phenanthroline

The complexes [Co(eee)(bipy)]Cl₃ and [Co(eee)(phen)]Cl₃ (eee, 1,8-diamino-3,6-dithiaoctane) were synthesized and characterized by two-dimensional NMR spectroscopy. The presence of the bidentate aromatic ligands 2,2-bipyridine and 1,10-phenanthroline caused the ¹H resonances to be spread into a wider spectral width than previously observed for [Co(eee)(NO₂)₂]Cl and [Co(eee)Cl₂]Cl. Separate multiplets were observed for the four protons in the terminal ethylene linkage. It was possible to positively assign each multiplet and to determine the relative spatial orientations of the corresponding protons.     

Coordination compounds of hydrazine derivatives with transition metals,part XVIII. Cobalt(II) and cobalt(III) chelates with schiff bases derived from hydrazine-S-methyldithiocarboxylate and thiosemicarbazide

Summary The reactions of aldehydic and ketonic Schiff bases derived from hydrazine-S-methyl dithiocarboxylate and thiosemicar-bazide with cobalt(II) acetate were investigated. Octahedral tris ligand cobalt(III) chelates were formed with aldehydic Schiff bases whereas tetrahedral bis ligand cobalt (II) chelates were isolated with ketonic Schiff bases.N-isopropylidene hydrazine-S-methyldithiocarboxylate, however, gave both octahedral tris cobalt(III) and tetrahedral bis cobalt(II) chelates. These results are interpreted in terms of the steric requirements of the Schiff base used.     

The crystal structure of tris (ethylenediamine), cobalt(III) hexacyanoferrate(III)dihydrate,Co(C2H8N2)3[Fe(CN)6] · 2H2O

The crystal structure of the title compound has been determined from three dimensional x-ray data obtained by the multiple film method. The space group is P2_l/n and the cell dimensions are: a = 14.90, b = 16.84, c = 8.38 Å; β = 93.5° Z = 4. The structure is formed by discrete Co (en) and Fe(CN) ions, both of which have an octahedral configuration. The Fe(CN) ions are approximately octahedrally surrounded by the Co (en) ions while arrangement of Fe (CN) ions around the Co(en) ions completely differs from an octahedron. The mean Fe? C and Co? C dustances are 1.91 and 2.01 Å, respectively. The water molecules do not play an important role in the structure and all distances between oxygen and other atoms indicate the presence of very weak hydrogen bonds. The salts M (en)₃ Q(CN)₆ · H₂O, where M = Co and Cr and Q = Cr, Mn, Fe and Co, are all isomorphous.     

2-(8-羟基喹啉-5-磺酸-7-偶氮)-1,8-二羟基-3,6-萘二磺酸与牛血清白蛋白的相互作用

用平衡透析法和分光光度法研究了 2 (8 羟基喹啉 5 磺酸 7 偶氮 ) 1,8 二羟基 3,6 萘二磺酸与牛血清白蛋白 (BSA)在酸性溶液中的结合反应 ,认为 8Q5SAC与BSA之间的结合力是以静电引力为主的非共键作用力 ,并探讨了其结合模型。在 2 98K下 ,测得这一反应的最大结合数为 35～ 40 ,结合常数为 6 .1× 10 5L mol。还研究了溶液基本条件如酸度和离子强度等对 8Q5SAC与牛血清白蛋白分子复合物形成的影响 ,在pH =3.34条件下 ,标准工作曲线的线性范围为 0 .2 0～ 46 .90mg L。     

Photometric determination of aqueous cobalt (II), nickel (II), copper (II) and iron (III) with 1-nitroso-2-naphthol-3,6-disulfonic acid disodium salt in gelatin films

Photometric determination of aqueous Co(II), Cu(II), Ni(II) and Fe(III) was performed using indicator films prepared by immobilization of 1-nitroso-2-naphthol-3,6-disulfonic acid disodium salt (NRS) into hardened photographic film. Immobilization was based on electrostatic interaction of reagent and metal complexes with the gelatin. The isoelectric point pH of hardened gelatin (4.46±0.04) was evaluated by viscometry. Co(II), Fe(III), Ni(II) form 1:3 complexes with NRS in gelatin at pH 2 and Cu(II) forms 1:2 complexes. Their log β′ values were: Co-6.7, Fe-8.6, Cu-8.0, and Ni-6.4. The absorption maxima were: 370nm for NRS, and 430nm, 470nm, 495nm and 720nm for complexes of Co(II), Ni(II), Cu(II) and Fe(III). An algorithm for their simultaneous determination using the indicator films was developed. The detection limits were: c_lim(Co²⁺) = 0.45×10⁻⁵ M, c_lim(Fe³⁺) = 0.50×10⁻⁵ M, c_lim(Cu²⁺) = 0.67×10⁻⁵ M, c_lim(Ni²⁺) = 0.75×10⁻⁵ M,; and their sum c_lim(ΣMn⁺) = 0.82×10⁻⁵ M.