Tetraphenylborate salts of alkali and alkaline earth metal complex cations

An introductory review summarises complex formation between poly(alkyleneoxy) adducts and inorganic salts. This is followed by preparative and IR and NMR spectroscopic features of the tetraphenylborates of complexes of polyethylene glycols, nonylphenoxy(polyethyleneoxy)ethanols and polypropylene glycols with sodium, magnesium, calcium, strontium and barium ions. Generally, an alkylene oxide:cation ratio of 8.5:1 is indicated for the complexes with sodium, and 12:1 (∼10.5:1 for the polyethylene glycols)_for the complexes with the alkaline earth metals.     

Synthesis and characterization of triphenylmethylphosphonium transition metal salts

Triphenylmethylphosphonium salts, [PPh3Me]aMXn (M=Cu2+, Co2+, Mn2+, Ni2+ Fe3+ Pb2+ and Hg2+; X=Cl or I; a=1 or 2 and n=3 or 4) prepared by reacting PPh3MeX with the metal dihalide in EtOH sol-utions, have been characterized by electronic, Raman, far i.r. and Mo¨ssbaur spectra and by their magnetic properties as well as by elemental analyses. The copper complexes [PPh3Me]2CuCl4 and [PPh3Me]2Cu3Cl8 were characterized by X-ray crystallography and the structures are described. Powder diffraction patterns have shown that the cobalt and manganese tetrachloride complexes are isomorphous. Investigation by d.s.c. measurements showed that the complexes exhibit structural phase transitions.     

低含氧量复合氟化物的溶剂热合成及表征

通过溶剂热法合成出钙钛矿结构复合氟化物KMF3(M=Mg，Zn，Co，Ni)及LiBaF3．用乙二醇做溶剂合成LiBaF3，KMgF3和KNiF3，反应物摩尔比均为1：1，反应温度180℃，反应时间分别为4，1和1d；用乙醇做溶剂合成KZnF3和KCoF3，反应物摩尔比为2：1和1：1，反应温度为180℃，反应时间均为1d．用XRD，SEM，TGA，IR及XPS等手段对产物进行了表征．     

有机杂化含Te2^2-／Se3^2-过渡金属化合物的溶剂热合成及晶体结构

本文通过溶剂热法合成了2种新的有机杂化锌碲化物[Zn(dien)2](Te2)(1)和镍硒化物[Ni(dien)2](Se3)(2)(dien=二乙烯三胺),单晶X射线衍射分析结果表明,化合物1属于正交晶系,Cmca空间群,晶胞参数:a=9.212(2),b=10.854(3),c=15.723(4),Z=4。化合物2属于正交晶系,Pna21空间群,晶胞参数:a=18.047(4),b=9.8236(19),c=9.0079(19),Z=4。在两种化合物中,1的阳离子中Zn2 与2个dien螯合形成稍变形的八面体几何构型,阴离子为哑铃型的Te22-。2的阳离子中Ni2 离子与2个dien螯合形成稍变形的八面体几何构型,阴离子为‘V’字型的Se32-。     

Thermochemistry of complex salts of transition metal perchlorates with tetrazole ligands

The combined use of combustion and solution calorimetry was proposed as a method for determining the standard enthalpy of formation of the complex salts of transition metals, viz., cobalt(II), nickel(II), and zinc, with the organic ligand (5-aminotetrazol-1-yl)acethydrazide. The enthalpies of solution in water and in a 0.1 M solution of hydrochloric acid were measured for the complex salts and ligand. The enthalpy of combustion of the ligand was determined by the combustion calorimetry method, and its standard enthalpy of formation was calculated. The thermochemical cycle was developed for determining the standard enthalpy of formation of the complex salts. The reliable values of the enthalpies of formation of the salts in the standard states were obtained, and the enthalpies of formation of the earlier unknown complex ions were determined.     

Thermochemistry of complex salts of transition metal perchlorates with tetrazole ligands

Standard enthalpies of formation of transition metal (cobalt, nickel, and zinc) complex salts with an organic ligand 5-aminotetrazol-2-ylacetohydrazide (ATH-2) were obtained by combustion and solution calorimetry. The enthalpy of combustion of the ligand was determined using combustion calorimetry and the standard enthalpy of formation of the ligand was calculated. For calculations by reaction calorimetry, a thermochemical cycle was developed that allows determination of the standard enthalpy of formation of complex salts. The enthalpies of solution of the ligand and transition metal complex salts in water and in 0.1 M hydrochloric acid were determined. The data obtained allow calculations of the enthalpies of salts formation and the enthalpies of three new complex ions. The enthalpies of position isomerization in different compounds were analyzed.     

New transition metal oxytrifluoromethanesulfonate salts

The reaction of (CF₃SO₂)₂O with salts containing a transition metal in a high oxidation state results in the formation of new transition metal oxytrifluoromethanesulfonate salts.     

Isolation of niobium,tantalum, and titanium complex fluoride salts with alkali metal cations

Fluoride and oxofluoride salts of niobium, tantalum, and titanium were isolated. They precipitated from aqueous solutions and upon washing of organic extracts with aqueous solutions of ammonium, potassium, and sodium salts. The compositions of the isolated compounds were studied. Different compositions were established for the niobium salts that precipitated upon the dissolution of unwashed niobium hydroxide in hydrofluoric acid under the atmospheric pressure, in an autoclave, and upon addition of sodium, potassium, and ammonium salts to purely fluoride solutions of niobium, as well as for the tantalum ammonium and sodium salts isolated from aqueous and organic solutions. The data obtained can be used for the synthesis of niobium, tantalum, and titanium complex fluoride salts with various compositions.     

Nitrosophenol complexes of transition metal salts

Complexes derived from 4-substituted-2-nitrosophenols, 3-Me-2-nitrosophenol, nitrosophyrogallol, nitrososalicylic acid and nitrosogallic acid with cobalt(II), nickel(II) and copper(II) have been prepared and characterized by elemental analysis, electronic and vibrational spectra, together with magnetic susceptibility measurements. The e.s.r. spectra of the copper(II) complexes were investigated, and detailed thermal properties of selected complexes are discussed.     

Solvothermal synthesis and structural characterization of a novel erbium(III)-carboxylate polymeric complex

A novel erbium(III)-carboxylate polymeric complex [{Er(H₂btec)_2/4(btec)_3/6(H₂O)}·2H₂O] _n , simplified as ECPC, (H₄btec=1,2,4,5-benzenetetracarboxylic acid) was synthesized under solvothermal conditions (H₂O/acetic acid). ECPC obtained was characterized by differential thermal analysis/thermogravimetry (DTA/TG), single-crystal X-ray diffraction, elemental analysis and FT-IR analysis techniques. The result of single-crystal X-ray diffraction analysis shows that the ECPC crystallizes in monoclinic symmetry, and the space group P2(1)/n, a=10.6933(15) Å, b=7.1243(10) Å, c=17.092(2) Å, α=γ=90°, β=97.109(2)°, V=1292.1(3) Å³, Z=4, R ₁=0.0286, wR ₂=0.0686. ECPC demonstrates a 3-D supramolecular framework containing nine-coordinate erbium centers and channels. The uncoordinated water molecules occupy the channels in ECPC. The results of TG/DTA, IR and elemental analysis performed also give positive information of the proposed crystal structure.     

Polymerization of N-vinylcarbazole by transition metal salts

The polymerization of N-vinylcarbazole (NVC) in the presence of transition metal salts such as WCI₆, MoCI₅, TaCl₅ and NbCl₅ under different reaction conditions was studied. In general, aromatic solvents were found to be superior to aliphatic solvents in the polymerization of NVC, i. e., both conversion and molecular weight were higher in aromatic solvents. It was observed that the polymerization reaction proceeds rapidly and almost quantitatively, even at low monomer concentration (< 5 × 10^?2M) and at low catalyst to monomer mole ratio (10^?5) in aromatic solvents. The copolymerization of NVC with acenaphthylene (ACN) was also investigated in solution at room temperature. The resulting homo- and copolymer were characterized by IR, NMR, x-ray diffraction, and elemental analysis. Thermal and photophysical properties are also reported. From the spectral data, the polymerization solvent was found to have a strong influence upon the polymer stereoregularity.     

Sorption of transition metal cations on natural heulandite

The cation exchange equilibrium in the systems of natural heulandite-binary aqueous solutions of NaCl, NiCl₂, CuCl₂, ZnCl₂, and MnCl₂ was studied. The corrected coefficients of the selectivity (k ^a _M/Na) and thermodynamic constants (K _M/Na) of the cation exchange of Na⁺ cations for transition metal cations were determined. The selectivity of the cation exchange on natural heulandite increases in the following order: Ni²⁺ < Cu²⁺ < Zn²⁺ < Na²⁺ < Mn²⁺.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1101–1103, May, 1996.     

Gas-phase ion/ion reactions of transition metal complex cations with multiply charged oligodeoxynucleotide anions

Multiply deprotonated hexadeoxyadenylate anions, (A6-nH)(n-), where n = 3-5, have been subjected to reaction with a range of divalent transition-metal complex cations in the gas phase. The cations studied included the bis- and tris-1,10-phenanthroline complexes of CuII, FeII, and CoII, as well as the tris-1,10-phenanthroline complex of RuII. In addition, the hexadeoxyadenylate anions were subjected to reaction with the singly charged FeIII and CoIIIN,N'-ethylenebis(salicylideneiminato) complexes. The major competing reaction channels are electron-transfer from the oligodeoxynucleotide anion to the cation, the formation of a complex between the anion and cation, and the incorporation of the transition-metal into the oligodeoxynucleotide. The latter process proceeds via the anion/cation complex and involves displacement of the ligand(s) in the transition-metal complex by the oligodeoxynucleotide. Competition between the various reaction channels is governed by the identity of the transition-metal cation, the coordination environment of the metal complex, and the oligodeoxynucleotide charge state. In the case of the divalent metal phenanthroline complexes, competition between electron-transfer and metal ion incorporation is particularly sensitive to the coordination number of the reagent metal complexes. Both electron-transfer and metal ion incorporation occur to significant extents with the bis-phenanthroline ions, whereas the tris-phenanthroline ions react predominantly by metal ion incorporation. To our knowledge this work reports the first observations of the gas-phase incorporation of multivalent transition-metal cations into oligodeoxynucleotide anions and represents a means for the selective incorporation of transition-metal counter-ions into gaseous oligodeoxynucleotides.     

The synthesis and characterization of some new vic-dioximes and their transition metal complexes

In this study, three new vic-dioximes, [L¹H₂], N-(5-chloro-2-methoxyphenyl)amino-1-acetyl-1-yclohexenylglyoxime, [L²H₂],N-(3-chloro-4-methoxyphenyl)amino-1-acetyl-1-cyclohexenylgly-oxime and [L³H₂], N-(3-chloro-2-methoxyphenyl)amino-1-acetyl-1-cyclohexenylglyoxime were synthesized from 1-acetyl-1-cyclohexeneglyoxime and the corresponding substituted aromatic amines. Metal complexes of these ligands were also synthesized with Ni(II), Cu(II) and Co(II) salts. The structures of these new compounds (ligands and complexes) were characterized with FT-IR, magnetic susceptibility measurement, molar conductivity measurements, mass spectrophotometer measurements, thermal methods (TGA), ¹H NMR and ¹³C NMR spectral data and elemental analyses.     

Enantioselective transition metal catalysis directed by chiral cations

Enantioselective transition metal catalysis directed by chiral cations is the amalgamation of chiral cation catalysis and organometallic catalysis. Thus far, three strategies have been revealed: ligand scaffolds incorporated on chiral cations, chiral cations paired with transition metal ‘ate’-type complexes, and ligand scaffolds incorporated on achiral anions. Chiral cation ion-pair catalysis has been successfully applied to alkylation, cycloaddition, dihydroxylation, oxohydroxylation, sulfoxidation, epoxidation and C–H borylation. This development represents an effective approach to promote the cooperation between chiral cations and transition metals, increasing the versatility and capability of both these forms of catalysts. In this review, we present current examples of the three strategies and suggest possible inclusions for the future.

Enantioselective transition metal catalysis directed by chiral cations is the amalgamation of chiral cation catalysis and organometallic catalysis.     

The synthesis and structural characterization of transition metal coordination complexes of coumarilic acid

The coumarilate (coum^?) complexes of Co^II(1), Ni^II(2) Cu^II(3) and Zn^II(4) were synthesized and characterized by elemental analysis, magnetic susceptibility, solid-state UV–Vis, FTIR spectra, thermoanalytical TG–DTG/DTA and single-crystal X-ray diffraction methods. It was found that all of the complex structures have 2 mol (coum^?) ligand bonded as monoanionic monodentate in the structures of 1 and 2 while they were coordinated to metal cations as monoanionic bidentate in the complexes 3 and 4. There was not any hydrate water in the metal complexes. The complexes of 1 and 2 have four moles of aqua ligand, and the other complexes have two moles. Thermal decomposition of each complex starts with dehydration, and then the decomposition of organic parts goes. The thermal dehydration of the complexes takes place in one (for the compounds of 2, 3, 4) or two (for the compound 1) steps. The decomposition mechanism and the thermal stability of the complexes under investigation were determined on the basis of their structures. Metal oxides were obtained as the final decomposition product.     

Extraction-ability and -selectivity of tetra-aza-crown ethers for transition metal cations

In order to investigate the relative effects of the differences between the structures and lipophilicities of 1, 10-dioxa-4, 7, 13, 16-tetra-azacyclo-octadecane (TA-18-crown-6) and the tetrabenzyl derivative of 1,10-dioxa-4, 7, 13, 16-tetra-azacyclo-octadecane (TBTA-18-crown-6) on their extraction-abilities and -selectivities for transition metal cations, constants of the overall extraction (logK _ex) of 1:1 (M:L) complexes, the distribution (K _D) for two diluents (CH₂Cl₂ and CHCl₃) with different dielectric constants have been determined at 25 ± 0.1 °C. The magnitude of logK _ex is largely determined by that of K _D. The equilibrium constants of TA-18-crown-6 have been compared with those of TBTA-18-crown-6. It is found that:(i) logK _ex sequences of TA-18-crown-6 and TBTA-18-crown-6 for transition metals in CH₂Cl₂ lie in order: Fe³⁺ > Cu²⁺ > Mn²⁺ > Co²⁺ > Cd²⁺ > Ni²⁺ > Zn²⁺ and Fe³⁺ > Cu²⁺ > Co²⁺ > Mn²⁺ > Ni²⁺ > Cd²⁺ > Zn²⁺ respectively; (ii) the stability sequences of two types of tetra-aza-crown ethers with the transition metal cations in CHCl₃ are the same as follows: Fe³⁺ > Ni²⁺ > Cu²⁺ > Co²⁺ > Zn²⁺ > Cd²⁺ > Mn²⁺, and (iii) unusual selectivities are observed for transition metal-tetra-aza-crowns, e.g. the high Fe³⁺/M ⁿ⁺ selectivity factors (S_f) of TA-18-crown-6, except for the competitive-extractions for the special case in CHCl₃ of TBTA-18-crown-6, it was found that the Mn²⁺/M ⁿ⁺ values were relatively higher according to the other transition metal cations. A systematic sequence in these two types of solvents is not found for a given transition metal cation in terms of the variation of selectivity with the tetra-aza-crown ethers. The results provide alternatives for the rational design of other specific ligands on the transition metal cations.