Structure of sulfanilamide-containing cobalt(III) dioximates with the [ZrF<Subscript>6</Subscript>]<Superscript>2−</Superscript> and [BF<Subscript>4</Subscript>]<Superscript>−</Superscript> anions

The complexes [Co(DH)₂(Sam)₂]₂[ZrF₆]·5H₂O (I) and [Co(DH)₂(Sam)₂][BF₄]·H₂O (II), where DH^? is the dimethylglyoxime monoanion, and Sam is para-aminobenzenesulfamide (sulfanilamide, white streptocid), were synthesized, and their crystal structures were determined by X-ray diffraction analysis. The coordination polyhedron of the Co³⁺ atom is an N₆ octahedron formed by four nitrogen atoms of the two dimethylglyoxime residues and two nitrogen atoms of the Sam fragments. The latter are realized in virtually parallel orientation relative to the polyhedron of the metal atom and its equatorial plane; the average value of the dihedral angles is 26.8(1)°, and there is π-π interaction between the benzene rings of the Sam fragments and the π delocalized equatorial metallocycle. The deviation of the cobalt atom from the four-angle plane is up to 0.009(1) Å. The (Co-N)_DH? and (Co-N)_Sam distances in the [Co(DH)₂(Sam)₂]⁺ complex cations vary from 1.892(2) Å to 1.907(3) Å and from 2.000(2) Å to 2.012(2) Å, respectively. The [ZrF₆]^2? and [BF₄]^? complex anions play the major role in crystal formation; they produce a substantial effect on the formation of a complex system of hydrogen bonds.     

Interaction of [В<Subscript>10</Subscript>H<Subscript>10</Subscript>]<Superscript>2–</Superscript> and [В<Subscript>12</Subscript>H<Subscript>12</Subscript>]<Superscript>2–</Superscript> with nitro compounds

The interaction of the [B₁₀H₁₀]^2– and [B₁₂H₁₂]^2– anions with aliphatic and aromatic nitro compounds (RNO₂, where R = Et, n-Pr, i-Pr, tert-Bu, Ph) has been studied under irradiation with visible and UV light. It has been shown that, depending on the reaction conditions, both mono- and disubstituted nitro-closo-decaborates can be selectively obtained in yields up to 50%.     

Composition and structure of hydrates of CH<Subscript>3</Subscript>COOH molecules and CH<Subscript>3</Subscript>CO<Subscript>2</Subscript><Superscript>−</Superscript> anions in aqueous solutions

The optimal configurations, energy parameters, and normal vibrational frequencies of hydrates of the acetic acid molecule and anion (CH₃COOH·(H₂O) _n (n = 1-10) and CH₃CO₂^??(H₂O) _n (n = 1-8, 16)) are calculated by density functional theory (B3LYP/6-31++G(_d,_p)). The comparison of the calculation results with the known experimental data (Raman, NMR, and so on) gives arguments in favor of the existence of two stable heteroassociates (HAs) in СН₃СООН–H₂O solutions: previously found CH₃COOH·(H₂O)₂ heterotrimer and CH₃COOH·(H₂O)₈, and three complexes (CH₃CO₂^??(H₂O)₂, CH₃CO₂^??(H₂O)₆, and CH₃CO₂^??(H₂O)₁₆) in NaCH₃CO₂^?–H₂O solutions. Each of them is most stable in a series of isomers, contains unstrained H bonds, and is characterized by the maximum molecular packing density among HAs with similar n values. The structure of the subsequent complex formed in solution uniquely follows the structure of the preceding complex and is based on it.     

Identification of Anionic Supramolecular Complexes of Sulfonamide Receptors with Cl<Superscript>−</Superscript>, NO<Stack><Subscript>3</Subscript><Superscript>−</Superscript></Stack>, Br<Superscript>−</Superscript>, and I<Superscript>−</Superscript> by APCI-MS

As part of a mass spectrometric investigation of the binding properties of sulfonamide anion receptors, an atmospheric pressure chemical ionization mass spectrometric (APCI-MS) method involving direct infusion followed by thermal desorption was employed for identification of anionic supramolecular complexes in dichloromethane (CH₂Cl₂). Specifically, the dansylamide derivative of tris(2-aminoethyl)amine (tren) (1), the chiral 1,3-benzenesulfonamide derivatives of (1R,2S)-(+)-cis-1-amino-2-indanol (2), and (R)-(+)-bornylamine, (3), were shown to bind halide and nitrate ions in the presence of (n−Bu)₄N⁺X⁻ (X⁻ = Cl⁻, NO₃⁻, Br⁻, I⁻). Solutions of receptors and anions in CH₂Cl₂ were combined to form the anionic supramolecular complexes, which were subsequently introduced into the mass spectrometer via direct infusion followed by thermal desorption. The anionic supramolecular complexes [M+X]⁻, (M=1–3, X⁻=Cl⁻, NO₃⁻, Br⁻, I⁻) were observed in negative mode APCI-MS along with the deprotonated receptors [M−H]⁻. Full ionization energy of the APCI corona pin (4.5 kV) was necessary for obtaining mass spectra with the best signal-to-noise ratios.     

Study on the thermal behavior of the complexes of the type [PdX<Subscript>2</Subscript>(tdmPz)] (X = Cl<Superscript>−</Superscript>, Br<Superscript>−</Superscript>, I<Superscript>−</Superscript>, SCN<Superscript>−</Superscript>)

Four new mononuclear Pd(II) complexes of the type [PdX₂(tdmPz)] {X = Cl⁻ (1); Br⁻ (2); I⁻ (3); SCN⁻ (4); tdmPz = 1-thiocarbamoyl-3,5-dimethylpyrazole} have been synthesized and characterized by elemental analysis, IR spectroscopy, ¹H and ¹³C{¹H}-NMR experiments. The thermal behavior of the complexes 1–4 has been investigated by means of thermogravimetry (TG) and differential thermal analysis (DTA). From the initial decomposition temperatures, the thermal stability of the complexes can be ordered in the sequence: 3 < 4 ≡ 2 < 1. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction.     

Structures of the complex ions [CuCl<Subscript>4</Subscript>]<Superscript>2−</Superscript> and [CuCl<Subscript>5</Subscript>]<Superscript>3−</Superscript>

The electronic structures of the complex ions [CuCl₄]^2? and [CuCl₅]^3? were analyzed in terms of the extended angular overlap model (AOM) with consideration to sd and pd mixing. The total antibonding orbital energies of these ions show no anomalies in the transition from a tetrahedron to a planar square [CuCl₄]^2? and from a trigonal bipyramid to a tetragonal pyramid [CuCl₅]^3?. Presumably, the existence of numerous intermediate forms of these complexes is mainly due to the packing effects rather than the electronic factors.     

Structural investigation of salts containing ions [Pd(NH<Subscript>3</Subscript>)<Subscript>4</Subscript>]<Superscript>2+</Superscript> and [IrF<Subscript>6</Subscript>]<Superscript>2–</Superscript>

Double complex salts (DCS) α-[Pd(NH₃)₄][IrF₆]·H₂O (P2₁/m, a = 6.3181(3) Å, b = 10.8718(5) Å, с = 7.4526(4) Å, β = 103.568(2)°), β-[Pd(NH₃)₄][IrF₆]·H₂O (P2₁/с, a = 8.5773(3) Å, b = 10.8791(4) Å, с = = 12.6741(3) Å, β = 122.497(2)°), [Pd(NH₃)₄]₃[IrF₆]₂Cl₂·H₂O (P-1, a = 7.6080(2) Å, b = 7.6274(2) Å, с = 11.8070(3) Å, β = 122.497(2)°), and [Pd(NH₃)₄]₂[IrF₆]NO₃ (Fm-3m, a = 11.21210(10) Å) have been synthesized and structurally characterized for the first time. The existence of polymorphs for the DCS has been revealed. The influence of the chemical composition of the initial reagents on the reaction course and, respectively, the products, has been demonstrated. A hypothesis on the influence of the second coordination sphere on the formation of one or the other polymorph of the DCS has been suggested. It has been shown that the series α-[Pd(NH₃)₄][МF₆]·H₂O (M = Pt, Pd) exhibits isostructurality.     

Ionic complexes simultaneously containing fullerene anions and coordination structures of metal phthalocyanines with I<Superscript>−</Superscript> and EtS<Superscript>−</Superscript> anions

The ionic complexes simultaneously containing negatively charged coordination structures of metal phthalocyanines and fullerene anions, viz., {Mn^IIPc(CH₃CH₂S^?) _x ·(I^?)_1?x }·(C₆₀ ^·?)· ·(PMDAE⁺)₂·C₆H₄Cl₂ (PMDAE is N,N,N′,N′,N′-pentamethyldiaminoethane, x = 0.87, 1) and {Zn^IIPc(CH₃CH₂S^?)_y·(I^?)_1?y }₂·(C₆₀ ^?)₂·(PMDAE⁺)₄·(C₆H₄Cl₂) (y = 0.5, 2) were synthesized. The both compounds were obtained as single crystals, which made it possible to study their crystal structures. In complex 1, the fullerene radical anions form honeycomb-like layers in which each fullerene has three neighbors with center-to-center interfullerene distances of 10.13–10.29 Å. Rather long distances between the C₆₀ ^·? radical anions results in the retention of monomeric C₆₀ ^·? in this complex down to the temperature of 110(2) K. In complex 2, fullerenes form dimers (C₆₀ ^?)₂ bonded by one C-C bond. The dimers are packed in corrugated honeycomb-like layers with interfullerene center-to-center distances of 9.90–10.11 Å. Manganese(II) and zinc(II) phthalocyanines coordinate iodide and ethanethiolate anions to the central metal atom to form unusual negatively charged coordination structures M^IIPc(An^?) (An^? is anion) packed in dimers {M^IIPc(An^?)}₂ with a short distance between the phthalocyanine planes (3.14 Å in 1 and 3.27 Å in 2). The pthalocyanine dimers also form layers with the PMDAE⁺ cations, and these layers alternate with the fullerene layers. The packing of spherical fullerenes with planar phthalocyanine molecules is attained by the insertion of fullerenes between the phenylene groups of phthalocyanines. The π-π-interactions of the porphyrin macrocycle with five- or six-membered fullerene rings are characteristic of the earlier studied ionic porphyrin and fullerene complexes. Such interactions are not observed for ionic complexes 1 and 2.     

Peroxide derivatives of heteropoly compounds with Keggin anions [PW<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>3−</Superscript> and [SiW<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>4−</Superscript>: Synthesis and structure

Peroxide derivatives of heteropoly compounds with Keggin anions [PW₁₂O₄₀]^3? and [SiW₁₂O₄₀]^4? are isolated in an individual state from concentrated hydrogen peroxide solutions and characterized by physicochemical methods. The structure of Ba₂[SiW₁₂O₄₀] · 4H₂O₂ · 11H₂O (I) is solved by X-ray crystallography. Crystals of compound I (H₃₀Ba₂O₅₉Si₁W₁₂, FW = 3483.21) are monoclinic, space group C2/c, a = 24.981(2) Å, b = 12.2103(11) Å, c = 18.7142(17) Å, β = 122.620(2)^o, V = 4808.0(8) ų, Z = 4. The structure contains Keggin anions [SiW₁₂O₄₀]^4?; all hydrogen peroxide molecules are coordinated to Ba²⁺ cations.     

Experimental Determination of the Isotherm at 15°C of the System Mg<Superscript>2+</Superscript>/Cl<Superscript>−</Superscript>, SO<Subscript>4</Subscript><Superscript>2</Superscript>–H<Subscript>2</Subscript>O

Summary.  The diagram of the ternary system Mg²⁺/Cl⁻, SO₄ ²⁻–H₂O was established at 15°C by means of analytical and conductimetric measurements. Three compounds were found in this diagram, which are MgSO₄·6H₂O, MgSO₄·7H₂O, and MgCl₂·6H₂O. The solubility field of MgSO₄·7H₂O is important whereas those of MgSO₄·6H₂O and MgCl₂·6H₂O are small. The compositions (mass-%) of the two invariant points determined by the two methods are: MgSO₄:MgCl₂=2.73:33.80 and MgSO₄: MgCl₂=3.38:28.91. Both the measured and the calculated isotherm at 15°C have been used for modelling of the diagram Mg²⁺/Cl⁻, SO₄ ²⁻–H₂O between 0 and 35°C. The polythermal invariant point was approximately located between 15 and 10°C.  Corresponding author. E-mail: ariguib@planet.tn Received October 16, 2002; accepted (revised) December 3, 2002 Published online April 24, 2003 RID="a" ID="a" Dedicated to Prof. Dr. Heinz Gamsj?ger on the occasion of his 70^th birthday     

Nucleophilic addition of aromatic amide oximes to [2-B<Subscript>10</Subscript>H<Subscript>9</Subscript>NCC<Subscript>2</Subscript>H<Subscript>5</Subscript>]<Superscript>–</Superscript> anion

A series of closo-decaborate anions containing an O-iminoacylamide oxime fragment were synthesized by nucleophilic addition of aromatic amide oximes to 2-propionitrilium closo-decaborate anion. The isolated compounds were characterized by IR, ¹H, ¹³C–{¹H}, and ¹¹B–{¹H} NMR, and mass spectra. The structure of (Ph₄P)[2-B₁₀H₉NH=C(Et)ON=C(NH₂)C₆H₄Me-2] was determined by single-crystal X-ray analysis.     

Mercury complex [(HOCH<Subscript>2</Subscript>)<Subscript>3</Subscript>CNH<Subscript>3</Subscript>]<Stack><Subscript>2</Subscript><Superscript>+</Superscript></Stack> [HgI<Subscript>4</Subscript>]<Superscript>2−</Superscript>: Synthesis and structure

The complex [(HOCH₂)₃CNH₃] ₂ ⁺ [HgI₄]^2? (I) was synthesized by reacting (trioxymethyl)methylammonium iodide with mercury dioide (2: 1 mol/mol) in acetone. X-ray crystallography shows that the complex consists of two types of crystallographically independent [(HOCH₂)₃CNH₃]⁺ cations and tetrahedral anions [HgI₄]^2? (IHgI, 106.49(2)°–113.99(4)°; Hg-I, 2.7849(8)-2.8105(8) Å. [(HOCH₂)₃CNH₃]⁺ cations are linked via hydrogen bonds O…H-N and O-H…N (O…N, 2.84–2.92 Å) to form polymer chains, which are cross-linked with one another via anions (I…H, 2.81, 2.82 Å).     

Synthesis and crystal structure of complex [Mn(Imdc)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>] · 2H<Subscript>2</Subscript>O and its interaction with DNA

Under hydrothermal conditions, the complex [Mn(lmdc)₂(H₂O)₂] · 2H₂O (I) was synthesized and characterized by elemental analysis and IR spectrum (HImdc = 4,5-imidazofedicarboxylic acid). The crystal structure of I was determined by single-crystal X-ray diffraction (crystallizing in the monoclinic crystal system, P ₂/c space group, a = 11.000(2), b = 7.1281(14), c = 12.696(3) Å, β = 122.45(3), Z = 2. In I, the Mn²⁺ ion was chelated by two Imdc with one of their nitrogen atoms and a carboxylic oxygen atom, while two water molecules occupy the axial position of the Mn atom forming a distorted octahedral geometry. Three-dimensional structure of I was formed by intermolecular hydrogen bonds. UV-Vis and fluorescence spectra of I interacting with DNA show that insertion is the main binding mode between I and fish sperm DNA. Gel electrophoresis shows that I cleaves both supercoiled and circular pBR322 DNA to form a small molecular fragment.     

Clathrate [Zn(C<Subscript>6</Subscript>H<Subscript>5</Subscript>COO)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>] · 2CH<Subscript>3</Subscript>COOH: Synthesis and crystal structure

The clathrate [Zn(C₆H₅COO)₂(H₂O)₂] · 2CH₃COOH (I) was obtained for the first time from zinc(II) benzoate. The individuality, the unit cell parameters, and the number of “guest” molecules in complex I were determined from X-ray diffraction and derivatographic data. Its crystal structure was solved.     

Reaction of the [B<Subscript>10</Subscript>H<Subscript>9</Subscript>O<Subscript>2</Subscript>C<Subscript>4</Subscript>H<Subscript>8</Subscript>]<Superscript>–</Superscript> anion with C-nucleophiles

The reactions of 1,4-dioxane-substituted closo-decaborate anion ([B₁₀H₉O₂C₄H₈]^–) with metal acetylenides, diethyl malonate, ethyl acetoacetate, triethyl orthoformate, acetylacetone, and malonodinitrile were studied. The reactions were shown to be accompanied with substituent ring opening and attachment of the corresponding pendant functional group. The obtained compounds were characterized by various physicochemical methods (IR and polynuclear NMR spectroscopy, ESI mass spectrometry).     

Structure,physicochemical properties,and reactivity of the [B<Subscript>9</Subscript>H<Subscript>9</Subscript>]<Superscript>2–</Superscript> anion

Data on the structure, properties, and reactivity of one of the least studied 3D aromatic clusters—nonahydro-closo-nonaborate anion [B₉H₉]^2–—have been systematized. It has been shown that the key aspects of its reactivity are related to structural flexibility, which essentially distinguishes the [B₉H₉]^2– anion from the higher representatives of closo-borate anions.     

Synthesis and crystal structures of [K(H<Subscript>2</Subscript>O)(Piv)]<Subscript>∞</Subscript> and [K<Subscript>2</Subscript>(Phen)(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>(Piv)<Subscript>2</Subscript>]<Subscript>∞</Subscript>

A method for the synthesis of potassium pivalates (trimethylacetates) from potassium tert-butoxide and pivalic acid was proposed. The complexes of the formulas [K(H₂O)(Piv)]_∞(I) and [K₂(Phen)(H₂O)₂(Piv)₂]_∞ (II) (Piv denotes the pivalate anion and Phen denotes 1,10-phenanthroline) were obtained and characterized by elemental analysis and IR and ¹H NMR spectroscopy. The crystal structures of complexes I and II were determined using X-ray diffraction. Crystal structure I has a layered motif with two nonequivalent K atoms (C.N.s 5 + 2 and 6). The coordination of phenanthroline in II gives rise to a ribbon motif, the structure containing three nonequivalent K atoms (C.N.s 6, 6 + 1, and 8).     

Comparative study of Cl<Superscript>−</Superscript>, Br<Superscript>−</Superscript>, and I<Superscript>−</Superscript> ions adsorption from dimethyl formamide at Hg- and Ga-electrodes

The adsorption of Cl⁻, Br⁻, and I⁻ ions from their 0.1 M solutions in dimethyl formamide at renewable liquid Hg- and Ga-electrodes was studied under similar experimental conditions by the differential-capacitance and jet-electrode methods. The data obtained points out to a strong effect of the metal nature on adsorption parameters and the halogenide-ion surface activity series. The halogenide-ion surface activity at the Hg-electrode increased in the following sequence: Cl⁻ < Br⁻ < I⁻; at the Ga-electrode, in the reverse sequence: I⁻ < Br⁻ < Cl⁻. The results are explained qualitatively in terms of the Andersen-Bockris model. It follows from the obtained data that (1) the free energy of the metal-halogenide-ion interaction increases in the following sequence: I⁻ < Br⁻ < Cl⁻; (2) the free energy of the Ga-halogenide-ion interaction exceeds that of the Hg⁻halogenide-ion interaction; and (3) the difference of the Cl⁻, Br⁻, and I⁻ ions interaction with the metals increased significantly when passing from Hg⁻ to Ga-electrode.