A new method of removing excess of reagent from organic phases in the solvent extraction of metal complex anions with quaternary ammonium salts: Spectrophotometric determination of micro amounts of cobalt with 2-nitroso-1-naphthol-4-sulfonic acid

The removal of excess reagent extracted into an organic phase in the solvent extraction of a metal complex anion with a quaternary ammonium ion is discussed. With a given chelating ligand (HO—R—SO₃H), the order of extractability is HO—R—SO₃^- > M(OR—SO₃)^n- > X^- > ^-O—R—SO₃^- when an anion such as nitrate or halide is added. If suitable amounts of the anion are added, only the excess of reagent can be removed. The principle is applied to the extraction with zephiramine of the cobalt complex anion formed with 2-nitroso-1-naphthol-4-sulfonic acid. Micro amounts of cobalt in pure nickel salts were determined spectrophotometrically.     

The Rules Governing the Formation of Silver Azide Photolysis Products

Irradiation of silver azide at λ = 365 nm (I > 1 × 10¹⁵ quantum cm^?2 s^?1) in a vacuum (1 × 10^?5 Pa) leads to an increase in the rate of photolysis and photoinduced current and the appearance of a new long-wave region of spectral sensitivity. The photolysis products, silver metal and gaseous nitrogen, are formed in a stoichiometric ratio on the surface of silver azide. The rate constants for silver azide photolysis were determined. Measurements of contact potential difference, current—voltage characteristics, photoelectromotive force, and photocurrent showed that AgN₃(A₁)—Ag (photolysis product) microheterogeneous systems were formed in silver azide photolysis. The limiting stage of silver azide photolysis is the diffusion of interstitial silver cations to the (T_nAg_m)⁰ neutral center.     

Reactivity,Syntheses, and Crystal Structures of Na5[MO2][X] with M = Co+, Ni+, Cu+; X = CO32—, SO42—, SO32—, S2—, and Na25[CuO2]5[SO4]4[S]

Na₅[CuO₂][CO₃], Na₅[CuO₂][SO₃], Na₅[CuO₂][S], and Na₅[CuO₂][SO₄] were obtained as single crystals and powders from reactions of Na₂O, Cu₂O, and Na₂X with X = CO₃^2—, SO₃^2—, S^2—, and SO₄^2—, respectively. A redox reaction between CdO and Co metal occurs in the presence of Na₂O and Na₂X, yielding Na₅[CoO₂][X] with X = CO₃^2— and S^2—. From a mixture of Na₂SO₄, CdO and Na₂O in Ni‐containers we observed the formation of Na₅[NiO₂][S] single crystals. Single crystals of Na₂₅[CuO₂]₅[SO₄]₄[S] can be grown by annealing Na₅[CuO₂][SO₃] at 600 °C, leading to the decomposition of SO₃^2—, yielding SO₄^2— and S^2— at 550 °C. The structures have been determined from single crystal data and powder data. All structures contain the isolated complex [MO₂]^3— in a dumb‐bell like arrangement. The main feature of these compounds is that the anions SO₄^2—, SO₃^2—, CO₃^2— and S^2— are not connected to the transition metal. The formation of Na₅[CuO₂][X] (X = S^2—, SO₄^2—, SO₃^2—, CO₃^2—) has been studied by thermal analysis and in situ X‐ray diffraction techniques. Infrared spectra confirm the presence of SO₄^2—, SO₃^2—, and CO₃^2—, respectively, in the structures.     

Hg2(CH3SO3)2: Synthese,Kristallstruktur, thermisches Verhalten und Schwingungsspektroskopie

Hg₂(CH₃SO₃)₂: Synthesis, Crystal Structure, Thermal Behavior, and Vibrational Spectroscopy Colorless single crystals of Hg₂(CH₃SO₃)₂ are formed in the reaction of HgO, Hg, and HSO₃CH₃. In the monoclinic compound (I2/a, Z = 4, a=883.2(2), b=854.0(2), c=1188.9(2) pm, β = 92.55(2)°, R_all=0.0445) the Hg₂²⁺ ion is coordinated by two monodentate CH₃SO₃^— anions. Further contacts Hg‐O occur in the range from 262 to 276 pm and lead to a linkage of the [Hg₂(CH₃SO₃)₂] units. The thermal analysis shows that Hg₂(CH₃SO₃)₂ decomposes at 300° yielding elemental mercury. The mass numbers of the species evolved lead to the assumtion that SO₃, SO₂, CO₂, CO and H₂CO are formed during the reaction. In the IR and the Raman spectrum the typical vibrations of the CH₃SO₃^— ion are observed, the Raman spectrum shows the Hg‐Hg stretching vibration at 177 cm^—1 within the Hg₂²⁺ ion additionally.     

Synthese und Kristallstruktur von CsAu(SO4)2

Synthesis and Crystal Structure of CsAu(SO₄)₂ Light yellow single crystals of CsAu(SO₄)₂ were obtained upon evaporation of a solution of Au(OH)₃ and Cs₂SO₄ in sulfuric acid (96 % H₂SO₄). In the crystal structure (monoclinic, P2₁/c, Z = 4, a = 1029.7(2), b = 893.4(2), c = 901.0(1) pm, β = 111.08(1)°) Au³⁺ is in square planar coordination of oxygen atoms which belong to four SO₄^— ions. According to [Au(SO₄)_4/2]^— puckered layers are formed which are connected by the Cs⁺ ions. The latter are surrounded by five chelating and three monodentate sulfate groups leading to a CN of 13.     

Darstellung von Tetramethylammoniumazidsulfit und Tetramethylammoniumcyanat‐Schwefeldioxid‐Addukt, [(CH3)4N]+[SO2N3]–, [(CH3)4N]+ [SO2OCN]– und Kristallstruktur von [(CH3)4N]+[SO2N3]–

Preparation of Tetramethylammonium Azidosulfite and Tetramethylammonium Cyanate Sulfur Dioxide‐Adduct, [(CH₃)₄N]⁺[SO₂N₃]^–, [(CH₃)₄N]⁺[SO₂OCN]^– and Crystal Structure of [(CH₃)₄N]⁺[SO₂N₃]^– Tetramethylammonium azide forms with sulfur dioxide an azidosulfite salt. It is characterized by NMR and vibrational spectroscopy and the crystal structure analysis. [(CH₃)₄N]⁺[SO₂N₃]^– crystallizes in the monoclinic space group P2₁/c with a = 551.3(1) pm, b = 1095.2(1) pm, c = 1465.0(1) pm, β = 100.63(1)°, and four formula units in the unit cell. The crystal structure possesses a strong S–N interaction between the N^3– anions and the SO₂ molecules. The S–N distance of 200.5(2) pm is longer than a covalent single S–N bond. The structure is compared with ab initio calculated data. Furthermore an adduct of tetrametylammonium cyanate and sulfur dioxide is reported. It is characterised by NMR and vibrational spectroscopy. The structure is calculated by ab initio methods.     

(–)‐α‐Isosparteine copper(II) diazide

In the title complex, [Cu(N₃)₂(C₁₅H₂₆N₂)], the Cu atom is surrounded by the two N atoms of the chelating (?)‐α‐isosparteine ligand and another two N atoms from the two azide anions, forming a distorted CuN₄ tetrahedron. The two azide anions are terminally bound to the Cu^II atom, and the dihedral angle between the N_sparteine—Cu—N_sparteine and N_azide—Cu—N_azide planes is 50.0 (2)°.     

(H3O)Nd(SO4)2

The crystal structure of oxonium neodymium bis(sulfate), (H₃O)Nd(SO₄)₂, shows a two‐dimensional layered framework assembled from SO₄ tetrahedra and NdO₉ tricapped trigonal prisms. One independent sulfate group makes four S—O—Nd linkages, while the other makes five such connections to generate an unprecedented anhydrous anionic [Nd(SO₄)₂]⁻ layer. To achieve charge balance, H₃O⁺ cations are inserted between adjacent layers where they participate in hydrogen‐bonding interactions with the sulfate O atoms of adjacent layers.     

K2[Hg(SO3)2]·2.25H2O

The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO₃)₂]²⁻ anions are grouped into centrosymmetric pairs and are surrounded by two K⁺ cations to give the overall layer composition {K₂[Hg(SO₃)₂]₂}²⁻. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO₃)₂]²⁻ anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K⁺ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH₄)₂[Hg(SO₃)₂] and Na₂[Hg(SO₃)₂]·H₂O are discussed.     

Thermodynamics of the chlorides,bromides, nitrates,bromates, iodates and sulphates of potassium and sodium in dioxane—water mixtures from conductance data at different temperatures

Studies on electrolytic conductance in dioxane—water mixtures of varying compositions at 30, 35, 40 and 45°C were initiated, in which the variations in the Walden product with solvent composition and temperature were reported and discussed with respect to theories concerning solvent structure and ion—solvent interactions. In the present communication, attempts have been made to evaluate the thermodynamic function (ΔG⁰_t) for the transfer of KCl, KBr, KNO₃, KBrO₃, KIO₃, K₂SO₄, NaCl, NaBr, NaNO₃, NaBrO₃, NaIO₃ and Na₂SO₄ from water to respective dioxane + water media, which would give some information regarding ionic solvation.     

A novel azide copper complex: [[Azido{bis[2-(piperidin-1-ylmethyl)pyridine]}copper(II)]perchlorate] hydrate

Synthesis and single crystal X-ray diffraction study were carried for compound {[Cu(C₁₁H₁₆N₄)₂(N₃)](ClO₄)} · H₂O (I). The structure is molecular, and the Cu²⁺ ion is in a five-coordinated compressed trigonal bipyramid environment. Copper ion is bound to five N atoms, in which four N atoms are from two chlelating ligands 2-(piperidin-1-ylmethyl)pyridine and the fifth N donor is from a monodentate azido ligand. The complex cations [Cu(C₁₁H₁₆N₄)₂(N₃)]⁺, the perchlorate anions, and solvent water molecules are further joined into three dimensional supramolecular networks by rich hydrogen bonds including strong O-H…N between solvent water and azide ion and O-H…O between solvent water and perchlorate ion, and weak hydrogen bonds C-H…O, and weak bifurcated hydrogen bonds C-H/C-H…N in which N atom of azide ion serving as bifurcated acceptor and two C-H groups as donors.     

Solvolysis Products of the Types [RhMeL2(Me3[9]aneN3)]2+ and [RuCl3—XLX(Me3[9]aneN3)](x)+ (x = 1‐2) and Preparation and Structure of [Ru([9]aneS3)(Me3[9]aneN3)](CF3SO3)2

Solvolysis of [RhMe(CF₃SO₃)₂(Me₃[9]aneN₃)] ( 1 ) (Me₃[9]aneN₃ = 1, 4, 7‐trimethyl‐1, 4, 7‐triazacyclononane) in CH₃CN, DMSO or pyrazole (L) leads to substitution of both trifluoromethylsulfonate ligands and formation of the cationic complexes [RhMeL₂(Me₃[9]aneN₃)](CF₃SO₃)₂ 3—5 . In contrast, treatment of [RuCl₃(Me₃[9]aneN₃)] ( 2 ) with Ag(CF₃SO₃) in a 1:3 ratio for 2h in CH₃CN leads to formation of the tetranuclear complex [{RuCl₃(Me₃[9]aneN₃)}₂Ag₂(CF₃SO₃)(CH₃CN)](CF₃SO₃) · CH₃CN ( 6 ) with a novel [(RuCl₃)₂Ag₂] core. More forcing conditions enable the substitution of respectively one or two chloride ligands by CH₃CN (reflux 18h) or DMF (85°C, 1h) to afford [RuCl₂(CH₃CN)(Me₃[9]aneN₃)](CF₃SO₃) ( 7 ) and [RuCl(DMF)₂(Me₃[9]aneN₃)](CF₃SO₃)₂ ( 8 ). The heteroleptic sandwich complex [Ru([9]aneS₃)(Me₃[9]aneN₃)](CF₃SO₃)₂ ( 9 ) can be prepared by reduction of 2 with Zn powder in acetone in the presence of 3 equiv. of Ag(CF₃SO₃), followed by addition of [9]aneS₃ (1, 4, 7‐trithiacyclononane). The redox potential E°(Ru³⁺/Ru²⁺) of +1.87 V vs NHE for 9 is only —0.12 V lower than that of the homoleptic complex [Ru([9]aneS₃)₂]²⁺. Crystal structures are reported for 3 — 9 .     

Low‐dimensional compounds containing cyano groups. VII.

The title compound, [Cu(C₂N₃)(C₁₂H₈N₂)₂](CF₃SO₃), is formed by discrete [Cu(phen)₂{N(CN)₂)}]⁺ complex cations (phen is 1,10‐phenanthroline) and uncoordinated CF₃SO₃⁻ anions. The Cu centre is five‐coordinated in the form of a distorted trigonal bipyramid to two phen mol­ecules and one dicyan­amide ligand, which is coordinated through one nitrile N atom in the equatorial plane at a distance of 1.990 (2) Å. The two axial Cu—N distances are similar (mean 1.993 Å) and are substantially shorter than the two equatorial Cu—N bonds (mean 2.125 Å).     

Synthesis and Crystal Structure of Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu4{CH2=CHCH2NHC(S)NH2}6](SO3CF3)4

Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu₄{CH₂=CHCH₂NHC(S)NH₂}₆](CF₃SO₃)₄ (sp.gr.P2₁/n, a = 13.5463(8), b = 24.129(2), c = 19.128(1)Å, β = 108.053(6)°, Z = 4, R = 0.0440 for 13548 unique reflections) was obtained by reduction of Cu(CF₃SO₃)₂ with excess of N—allylthiocarbamide in benzene medium. Four crystallographical independent Cu atoms possess trigonal environment of three S atoms of CH₂=CHCH₂NHC(S)NH₂ moiety and form Cu₄S₆⁴⁺ adamantane—like fragments. The latteres are connected with CF₃SO₃^— anions via (C)—H···F hydrogen bonds.     

Asymmetric heterobimetallic mixed-valence complex trans-[(SO3)Co(cyclam)(NCS)Ru(NH3)4(NCS)](BF4): Synthesis and characterization

[(SO₃)Co(cyclam)(NCS)] and [(SO₃)Co(cyclam)-NCS-Ru(NH₃)₄(NCS)](BF₄) complexes were synthesized and characterized by means of X-ray diffraction, electrochemistry, elemental analysis, and spectroscopic techniques. Crystallographic and FTIR data indicated NCS⁻ ligand is coordinated to Co through the nitrogen atom in the monomer species. Electrochemistry and FTIR data of the material isolated after reductive electrolysis of [(SO₃)Co(cyclam)(NCS)] hint that NCS⁻ and SO₃²⁻ are released thus forming [Co(cyclam)(L)₂]²⁺, where L is solvent molecules. The formation of the heterobimetallic mixed-valence complex induced a thermodynamic stabilization of Co and Ru metal atoms in the oxidized and reduced states, respectively. According to the Robin and Day classification, a Class II system with a comproportionation constant of 5.78 × 10⁶ is suggested for the mixed-valence complex based on the electrochemical and UV-Vis-NIR results.     

Komplexchemie reaktiver organischer Verbindungen. XLV. Metallorganische Methandiazo – Komplexe: Protonierung und Cycloaddition

Complex Chemistry of Reactive Organic Compounds. XLV. Organometallic Methanediazo Complexes: Protonation and Cycloaddition The reactions of the methanediazo tungsten complex (η⁵-C₅H₅)W(CO)₂(N₂CH₃) ( 1 ) with protic acids are strongly governed by solvent effects: while trifluoromethylsulfonic acid induces clean protonation with formation of the ionic derivative [(η⁵-C₅H₅)W(CO)₂(HN₂CH₃)]+CF₃SO₃? ( 3 ) when diethylether is used as a solvent, compound 4 is formed in the presence of acetonitril which latter solvent has good coordination capabilities itself. Compound 4 originates from a novel type of cycloaddition reaction in which the protonated species of composition [(η⁵-C₅H₅)W(CO)(CH₃CN)(HN₂-CH₃)]+CF₃SO₃? is involved. Complete elimination of the nitrogeneous ligand ensemble with concomitant formation of the halogen complex (η⁵-C₅H₅)W(CO)₂Br₃ ( 5 ) occurs upon treatment of 1 with hydrogen bromide.     

Streptidinium sulfate monohydrate

In streptidinium sulfate monohydrate {systematic name: 1,1′‐[(1S,3R,4S,6R)‐2,4,5,6‐tetrahydroxycyclohexane‐1,3‐diyl]diguanidinium sulfate monohydrate}, C₈H₂₀N₆O₄²⁺·SO₄²⁻·H₂O, at 100 (2) K, the components are arranged in double helices based on hydrogen bonds. One helix contains streptidinium cations and the other contains disordered sulfate anions and solvent water molecules. The helices are linked into a three‐dimensional hydrogen‐bonded network by O—H...O and N—H...O hydrogen bonds.     

Mono‐ and dinuclear CuII complexes of the benzyldipicolylamine (BDPA) ligand: crystal structure,synthesis and characterization

The crystal structures of mono‐ and dinuclear Cu^II trifluoromethanesulfonate (triflate) complexes with benzyldipicolylamine (BDPA) are described. From equimolar amounts of Cu(triflate)₂ and BDPA, a water‐bound Cu^II mononuclear complex, aqua(benzyldipicolylamine‐κ³N ,N′ ,N ′′)bis(trifluoromethanesulfonato‐κO )copper(II) tetrahydrofuran monosolvate, [Cu(CF₃SO₃)₂(C₁₉H₁₉N₃)(H₂O)]·C₄H₈O, (I), and a triflate‐bridged Cu^II dinuclear complex, bis(μ‐trifluoromethanesulfonato‐κ²O :O ′)bis[(benzyldipicolylamine‐κ³N ,N′ ,N ′′)(trifluoromethanesulfonato‐κO )copper(II)], [Cu₂(CF₃SO₃)₄(C₁₉H₁₉N₃)₂], were synthesized. The presence of residual moisture in the reaction medium afforded water‐bound complex (I), whereas dinuclear complex (II) was synthesized from an anhydrous reaction medium. Single‐crystal X‐ray structure analysis reveals that the Cu^II centres adopt slightly distorted octahedral geometries in both complexes. The metal‐bound water molecule in (I) is involved in intermolecular O—H…O hydrogen bonds with triflate ligands and tetrahydrofuran solvent molecules. In (II), weak intermolecular C—H…F(triflate) and C—H…O(triflate) hydrogen bonds stabilize the crystal lattice. Complexes (I) and (II) were also characterized fully using FT–IR and UV–Vis spectroscopy, cyclic voltammetry and elemental analysis.     

NOESY,HOESY, T1 and solid‐state NMR studies on [RuH(η6‐toluene)(Binap)](CF3SO3): a molecule with a strongly distorted piano‐stool structure

Detailed solution‐NMR studies on the distorted ruthenium hydride complex [RuH(η⁶‐toluene)(Binap)](CF₃SO₃) (2) are reported. NOE‐spectroscopy, together with low‐temperature ¹H and ³¹P NMR data, reveals restricted rotation around a P—C bond for a specific axial P—phenyl ring with the activation energy determined via simulation. From ¹⁹F, ¹H HOESY data, the approach of the triflate anion relative to the hydride ligand is established. Comparison of the quadrupole coupling constant C_QF from both solution‐ and solid‐state MAS‐NMR on the deuteride [RuD(η⁶‐benzene)(Binap)](CF₃SO₃) (1‐D) provide information on the nature of the Ru—H bond. Copyright © 2003 John Wiley & Sons, Ltd.     

Sur le passage des radicaux libres a travers l'interface separant deux phases liquides

Two immeseible solvents are brought in contact, the first containing a polymerization catalyst which is insoluble in the second solvent which does not the catalyst but contains a monomer which, in turn, is insoluble in the first solvent. At an appropiate temperature, polymerization occurs in the second solvent, initiated principally by free radicals escaping may be evaluated. Thus (CH₃)₂C(CN) escapes from toluene to water at 5% and SO₄^? from water to toluene at 0.06%. Dispersion agents generally diminish this yield. But it seems that SO₄^? reacts with the agent retained at the interface, producing a new free radical better able to escape to the organic phase.