Mutual Weakening of Hydrogen Bonds Between Hydrogen Fluoride and Proton Donors

The mutual effect of hydrogen bonds in BHF(HHal) _n complexes (Hal = F, Cl, Br, I; B = –, CH₃CN, NH₃; n = 1-3) was examined using the self-consistent field ab initio approach (6-31++G(d,p) and ECP-HW). When two and three equivalent H bonds are formed from the lone electron pairs of the fluorine atom of the HF molecule, the mutual weakening effect is 17% and 28%, respectively. The coefficients of the mutual effects of hydrogen bonds in HF(HHal)₂ and H₂O(HHal)₂ bridges are close in magnitude.     

Arrangement and Diffusive Mobility of Extraframework Species in the Hydrated Ammonium Forms of Zeolites Clinoptilolite and Chabazite

The location and diffusive mobility of ammonium ions and water molecules in the channels of the NH₄substituted forms of the natural zeolites clinoptilolite (NH₄)_6.5[Al_6.5Si_29.5O₇₂] · 12.6H₂O and chabazite (NH₄)_9.6Ca_0.6Na_0.3[Al_11.1Si_24.9O₇₂] · 25.8H₂O were studied by Xray diffraction analysis and ¹H NMR spectroscopy. The arrangement of the extraframework subsystem was shown to be largely determined by hydrogen bonds N—H...O(H₂O) of length 2.7–2.9 . The diffusive mobility of the ions was found to correspond to abnormally low energy barriers, similar to those for H₂O diffusion. The activation parameters for the diffusion jumps of the ions and molecules are E(NH₄) = E(H₂O) = 31(2) kJ/mole, ₀(NH₄) = 2 · 10¹¹ sec^-1, ₀(H₂O) = 4 · 10¹² sec^-1 in NH₄chabazite and E(NH₄) = E(H₂O) = 25(1) kJ/mole, ₀(NH₄) = 2 · 10¹⁰ sec^-1, ₀(H₂O) = 3 · 10¹¹ sec^-1 in NH₄clinoptilolite. It is suggested that the development of ion and molecular diffusion is caused by the same defects, whose formation with temperature rise is controlled by Hbond rearrangement.     

Thermodynamic Study of the Aqueous Rubidium and Manganese Bromide System

Crystallization of 2RbBr · MnBr₂ · 2H₂O, the only double salt obtained under standard conditions from saturated aqueous rubidium–manganese bromide solutions, was theoretically predicted using the hard and soft Lewis acids and bases concept and Pauling's rules. The RbBr—MnBr₂—H₂O system was thermodynamically simulated by the Pitzer model assuming a solubility diagram of three branches only: RbBr, 2RbBr · MnBr₂ · 2H₂O and MnBr₂ · 4H₂O. The theoretical result was experimentally proved at 25°C by the physicochemical analysis method and formation of the new double salt 2RbBr · MnBr₂ · 2H₂O was established. It was found to crystallize in a triclinic crystal system, space group –P1, a = 5.890(1) Å, b = 6.885(1) Å, c = 7.367(2) Å, = 66.01(1)°, = 87.78(2)°, = 84.93(2)°, V = 271.8(1) ų, Z = 1, D _x = 3.552 g-cm^–3. The binary and ternary ion interaction parameters were calculated and the solubility isotherm was plotted. The standard molar Gibbs energy of the synthesis reaction, _rG _m ^o , of the double salt 2RbBr · MnBr₂ · 2H₂O from the corresponding simple salts RbBr and MnBr₂ · 4H₂O, as well as the standard molar Gibbs energy of formation, _fG _m ^o , and standard molar enthalpy of formation _fH _m ^o of the simple and double salts were calculated.     

In vitro and in vivo antitumour studies of a new thiosemicarbazide derivative and its complexes with 3d-metal ions

A new ligand, 1-(2-furanthiocarbo)-3-thiosemicarbazide (H₂ftsc), prepared from thiosemicarbazide and carboxymethyl-2-furandithioate, forms complexes [Mn(ftsc)(H₂O)₂], [Pd(ftsc)] · 2H₂O, [M(Hftsc)(acac)₂] (M=Co^III or Cr^III), [M(Hftsc)₂(acac)] (M=Mn^III or Fe^III) and [Zn(Hftsc)₂] · 2H₂O, which were characterized by elemental analyses, magnetic susceptibility, i.r., electronic and n.m.r. spectral data. The Mössbauer spectra of [Fe(Hftsc)₂(acac)] at 298K and 80K suggest the presence of high-spin iron(III) with an S=5/2 state. In vivo and in vitro antitumour activity of the ligand and the complexes have been screened towards several tumour cell-lines.     

Polymorphism of Crystalline Inclusion Complexes and Unsolvated Hosts. Part 8

Crystallization of cyclotriveratrylene (CTV) from solutions in acetone at 40°C gave a new 4:1 host-guest complex instead of the conventional 2:1 clathrate (-phase) whose X-ray crystal structure was determined. Data for 2(C₂₇H₃₀O₆) · 0.5(CO(CH₃)₂): monoclinic, P2₁/c, a = 18.942(4), b = 24.697(5), c = 10.508(2) Å, = 91.10(2)°, V = 4915(2) ų, Z = 8, D _x = 1.257 g/cm³, T = 293 K, R = 0.077 (for 2694 reflections). One of the two crystallographically independent CTV molecules (molecule A) is stacked into columns characteristic of the CTV - or -phase complexes. Molecules B face each other enclathrating inside around the inversion center disordered acetone molecules giving rise to the molecular capsule. The acetone molecule is H-bonded simultaneously to both host molecules by C(H₂)--H ··· O type bonds forming centrosymmetric dimers. Dimers are incorporated together with two A molecules into centrosymmetric units also by C(H₂)--H ··· O type H-bonds. Packing of these units gives rise to the crystal structure of the clathrate.     

Some compounds of iron(III) with tertiary and secondary nitrogen bases

Summary The iron(III) compound, FeCl(OH)(MeCO₂) · MeCO₂ H · 0.5 H₂O, combines with tertiary nitrogen bases, pyridine, quinoline and-picoline, to form FeCl(OH)(MeCO₂) · (Base) 0.5 H₂O and with-picoline to give FeCl(OH)(MeCO₂) (-picoline). The secondary nitrogen bases (BH), such as, piperidine, pyrrolidine and diethylamine, on the other hand, react with the elimination of base hydrochloride to form Fe(B)(OH)(MeCO₂) · 0.5 H₂O compounds, containing covalently bonded bases. Pyrrole and indole (BH) combine with the partial elimination of chlorine to give Fe₃Cl₂(B)(OH)₃(MeCO₂)₃ · 3(BH). Phthalimide (BH), however, forms a simple addition compound Fe₂Cl₂(OH)₂(MeCO₂)₂ · (BH). The i.r. spectra, room temperature magnetic susceptibilities, thermal decompositions wherever possible and molar conductance have been studied.     

Crystalline Inclusion Compounds Derived from 1,1'-Bis(ethenyl-2-pyridyl)ferrocene and (±)-1,1'-Bi-2-naphthol in Different Solvents

Crystallization of organometallic dipyridine(1,1'-bis(ethenyl-2-pyridyl)-ferrocene) (1) with(±)-1,1'-bi-2-naphthol (2) from EtOH,i-PrOH, (±)-2-BuOH, and MeOH forms crystallineinclusion compounds of stoichiometries1 2 C₂H₅OH (3, 1 2 C₃H₇OH (4),1 2 C₄H₉OH (5),and 1 2 CH₃OHH₂O(6), respectively. Thecrystalline species 3, 4, and 5 areisostructural with the three molecular componentsinterlinked by hydrogen bonds to form a columnarstructure. In 6, the four molecular componentsare interlinked by hydrogen bonds to form atwo-dimensional framework structure.     

Kinetic parameters of the cyclization and decyclization reactions of nitrogen- and oxygen-containing radicals

The intersecting parabolas model is used to analyze experimental data for the following radical cyclization and decyclization reactions: RCH=CH(CH₂)_nN·R₁ cyclo-[NR₁CH(CH₂)_n]C·HR,R(CH₂)₂OOCH₂C·HR cyclo-[RCHOCH₂] + RCH₂CH₂O·, cyclo-[(CH₂)_nOOCHC· HR] cyclo-[RCHOCH](CH₂)_nO·, cyclo-[(CH₂)_nOC·RO] RC(O)O(CH₂) _n–1C·H₂, and cyclo-[(CH₂)_nCHO·] CH(O)(CH₂) _n–1C·H₂. The activation energy of the thermally neutral reaction (E _e,0) is calculated for each class of reactions. E _e,0 depends on the electronegativity of the heteroatom Y of the reaction center C C...Y, the force constants of the reacting bonds, and the strain energy of the ring formed. For the cyclization and decyclization of six-membered rings, the empirical relationship between the elongation of the reacting bonds in the transition state (r _e) and the difference in electronegativity (EA) between the C and Y atoms (Y = C, N, O) has the form r _e ×10₁₁, m = 3.83 – 0.0198(EA, kJ/mol).Translated from Kinetika i Kataliz, Vol. 46, No. 1, 2005, pp. 5–13.Original Russian Text Copyright © 2005 by Denisova, Denisov.     

Characteristic Features of the Formation of Copper(I) π-Complexes with N-Allyl Derivatives of Piperazinium Sulfamate

The crystals of two copper(I) complexes and piperazinium sulfamate were synthesized by ac electrochemical technique from Cu(NH₂SO₃)₂· xH₂O and N,N-diallylpiperazine, N-allylpiperazine, or piperazine titrated by sulfamic acid in aqueous methanol to pH 4. The crystal structures of the complexes were determined (DARCh diffractometer, MoK radiation, /2 scan mode). The crystal data: [C₃H₅NH(CH₂)₄NHC₃H₅]_0.5[Cu(NH₂SO₃)₂] · H₂O (I), space group P1¯, a = 8.053(1) Å, b = 10.247(2) Å, c = 8.918(2) Å, = 113.03(1)°, = 107.14(2)°, = 95.15(1)°, Z = 2; [NH₂(CH₂)₄NH₂]_0.5NH₂SO₃ (II), space group P2₁/a, a = 8.468(7) Å, b = 5.92(1) Å, c = 10.890(9) Å, = 100.40(9)°, Z = 4; {[C₃H₅NH(CH₂)₄NHC₃H₅][NH₂(CH₂)₄NH₂]}_0.5[Cu(NH₂SO₃)₃] · H₂O (III), space group P1¯, a = 11.729(3) Å, b = 8.266(2) Å, c = 10.611(3) Å, = 82.13(2)°, = 65.73(2)°, = 74.86(2)°, Z = 2. Structure III is a hybrid of elements of structures I and II and contains the -coordinated Cu(I) atom surrounded by three -donor sulfamate nitrogen atoms, which was found for the first time.     

Synthesis and X-ray structural characterization of cobalt(II), copper(II), and silver(I) complexes of triphenylphosphoniopropionate

Four transition-metal carboxylate-like complexes have been synthesized from the reaction of the tertiary phosphine betaine triphenylphosphoniopropionate, Ph₃P⁺(CH₂)₂CO ₂ ^– , with Co(ClO₄)₂· 6H₂O, Cu(ClO₄)₂·6H₂O, Cu(BF₄)₂·xH₂O, and AgClO₄, respectively, and fully characterized by single-crystal X-ray analysis. [CoPh₃P(CH₂)₂CO_{2 4}(H₂O)₂](ClO₄)₂·2H₂O, 1, space groupP¯ l witha=9.195(2),b=13.000(2),c=18.795(3) Å,=102.52(1),=90.12(1),=109.28(2)° andZ=1; [CuPh₃P(CH₂)₂CO_{2 4}][Cu₂ -Ph₃P(CH₂)₂CO₂ -O,O ₄(H₂O)₂] (ClO₄)₆· 4H₂O, 2, space groupP2_l/c witha=14.225(3),b=24.624(6),c=24.297(5) Å,=94.18(1)°, andZ=2; [CuPh₃,P(CH₂)₂CO₂Me₂N(CH₂)₂NMe₂(H₂O)₂](BF₄)₂,3, space groupP2_l/c witha=17.668(2),b=13.454(3),c=15.876(2) Å,=116.45(1)°, andZ=4; [Ag₂Ph₃P(CH₂)₂CO_{2 2}(ClO₄)]₂(ClO₄)₂,4, space groupP¯ l witha=10.925(2),b=13.110(3),c=18.795(3) Å,=82.93(3),=87.45(3),=67.49(3)°, andZ=2. In complex1, the cobalt(II) atom is located in an inversion center and coordinated by four unidentate betaine ligands and a pair oftrans aqua ligands, and strong hydrogen bonds are formed between the aqua ligands and the pendant oxygen atoms of the betaine ligands. In complex2, mononuclear and dinuclear cations coexist in the asymmetric unit. In the mixed-ligand complex3 the betaine ligand acts in the unidentate coordination mode andN,N,N,N-tetramethylethylenediamine (tmen) in the chelate mode. Complex4 contains a discrete centrosymmetric tetranuclear cations in which one pair of betaine ligands act in the bidentate bridging mode and the other in both bidentate and one-atom bridging modes.     

Hydrophile-lipophile balance of alkyl ethoxylated surfactants as a function of intermolecular energies

Summary The semiempirical MNDO method has been used in order to examine the variation of the molecular properties of hydrocarbons C_nH_2n+2 (with 1n19) and ethylene oxide chains CH₃(CH₂CH₂O)_mCH₃ (with 1m19) as a function of their molecular length. Least-square fits of those properties have been calculated, along with two mathematical relations between the hydrophile-lipophile balance of alkyl-phenol ethoxylated surfactants and (1) the ratio of molecular lengths between their lipophilic and hydrophilic branches; (2) the intermolecular energies between the molecules of surfactant, water and hexane.     

Übèr das Kriechen kristallisierendèr Salze, 9. Mitt.: Die Darstellung von KClO3, KBr,CuSO4·5H2O und NaNH4HPO4·4H2O in besonders reinem Zustand

Zusammenfassung Neue experimentelle Daten werden angegeben, die eindeutig bestätigen, daß die kriechende Kristallisation als Methode zur weitgehenden Reinigung von Salzen verwendet werden kann.Angewandt bei KClO₃, KBr, CuSO₄·5H₂O und NaNH₄PO₄·4H₂O mit Reinheitsgrad zur Analyse mit Garantieschein (Schering-Kahlbaum, Deutschland), zeigte sich, daß die auf dem Gefäßboden ausgeschiedenen Kristalle in reinerem Zustand erhalten werden, als im Garantieschein angegeben ist.

---

The present paper offers new experimental data, which unambiguously confirm that creeping crystallisation can be used as a method for obtaining very pure salts.Applied to KClO₃, KBr, CuSO₄·5H₂O and NaNH₄HPO₄·4H₂O, with a purification grade zur Analyse mit Garantieschein (Schering-Kahlbaum, W. Germany) this method has shown that the crystals, obtained on the bottom of the vessel, are more pure than has been pointed out in the certificate.

     

Zwitterionic [(H3NCH2C≡CC≡CCH2NH3)]Cu2Cl4 π-Complex: Template Synthesis and Crystal Structure

Crystals of the [(H₃NCH₂CCCCCH₂NH₃)]Cu₂Cl₄ -complex, formed in the oxidative dimerization of propargylammonium cations, were obtained by ac electrochemical synthesis from CuCl₂ · 2H₂O and propargylammonium chloride ([CCCH₂NH₃]Cl) and studied by X-ray diffraction analysis (DARCh automated diffractometer, MoK radiation, /2 scan mode; 2275 reflections with F 4(F), R = 0.048). Crystals are monoclinic: space group B2/b, a = 19.591(6) Å, b = 7.299(3) Å, c = 8.636(3) Å, = 106.83(3)°, Z = 4. The structure consists of individual [(H₃NCH₂CCCCCH₂NH₃)]Cu₂Cl₄ moietes united through the elongated Cu···Cl contacts (2.827(5) Å) into chains oriented along the [010] direction. The bond of the centrosymmetric propargylammonium dimer is -coordintated by copper(I) atom and is elongated to 1.227(6) Å.     

On the thermal decomposition of [Fe2NiO(CH3COO)6(H2O)3]·2H2O

The heteronuclear-oxoacetate with the composition [Fe₂NiO(CH₂COO)₆(H₂O)₃]·2H₂O decomposed on heating, forming nickel ferrite NiFe₂O₄ and (depending on the decomposition conditions) in part other solid phases. H₂O, CH₃COOH, acetone and CO₂ were also formed in the decomposition. A reaction scheme is given for the decomposition. The products were porous powders with grain diameters between 3 and 10m. On increase of the temperature of decomposition from 300 to 800 C, the BET surface area and the surface area of the pores decreased, but only a small alteration in grain size was observed. As a result of thermal treatment in the temperature region abone 800C, larger aggregates of grains were formed in sintering processes.

---

Zusammenfassung Heteronukleare-Oxoazetate der Zusammensetzung [Fe₂NiO(CH₃COO)₆(H₂O)₃]·2H₂O werden durch Erhitzen zersetzt, wobei Nickelferrite NiFe₂O₄ und — in AbhÄngigkeit von den Bedingungen der Zersetzung — mit einem Teil anderer fester Phasen gebildet wird. In der Zersetzungsreaktion werden auch H₂O, CH₃COOH, Azeton und CO₂ gebildet. Es wird ein Reaktionsschema für die Zersetzung angegeben. Die Produkte sind poröse Pulver mit einem Korndurchmesser zwischen 3 und 10 m. Wird die Zersetzungstemperatur von 300 auf 800C erhöht, nimmt die BET-OberflÄche und die PorenoberflÄche ab, wobei sich die Korngrö\e aber nur wenig verÄndert. Im Ergebnis der WÄrmebehandlung im Temperaturbereich oberhalb 800C werden durch Sinterprozesse grö\ere Partikelaggregate gebildet.

     

Order and disorder in mixed metal linear chains: The homo and heterobimetallic EDTA (M(H2O)4OIOII)[M′(EDTA)] · 6H2O complexes (M = Mg,Mn, Co,Zn and Ni; M′ = Co,Ni, Cu and Zn)

Summary Polymetallic solid solutions of the ethylenediaminetetracetic acid (EDTA) and six divalent metal ions exist in the range: MgMnCoZnNiCu(EDTA) · 6H₂O where + + + + + =2, 01, 0,,2, 0, 1.This type of structure is characterized by the presence of two different octahedral carboxylate-bridged coordination sites forming infinite zig-zag chains. Visible and i.r. spectra and t.g.a. analysis show that there is occupational preference for the two coordination sites in the crystalline structure.Due to this preference, and also to the structural features, the heterobimetallic MM(EDTA) · 6H₂O compounds constitute a structurally new class of materials which can be described as ordered alternating-heterobimetallic polymeric coordination complexes.     

Symmetric binuclear complexes with an ‘end-off’ compartmental Schiff base ligand

Four binuclear transition metal(II) complexes: [Co₂L(-Cl)Cl₂] · 2H₂O, [Ni₂L(-Cl)Cl₂(H₂O)₂] · 2H₂O, [Cu₂L(-Cl)Cl₂] · 2H₂O and [Zn₂L(-Cl)Cl₂] · 2H₂O, where LH is the binucleating ligand 2,6-diformyl-4-methylphenol bis(2-hydrazino benzothiazole), were prepared. Based on the i.r. spectra, elemental analysis, conductivity measurements and thermal analysis, we propose that these complexes contain an endogenous phenoxide bridge and an exogenous chloride bridge. Magnetic and spectral data supports the existence of a weak antiferromagnetic interaction between the metal ions, and octahedral for Ni^II and a square pyramidal environment for remaining complexes. The compounds show significant growth inhibitory activity against the fungi, Aspergillus niger and Candida albicans, as compared to antibacterial activity against Bacillus cirroflagellosus and Pseudomonas auregenosa.     

Crystal Structure of the Ca2+ Supramolecular Complex with Cucurbituryl {[Ca(H2O)3(HSO4)(CH3OH)]2(C36N24O12H36)}(HSO4)2 · 4H2O

The calcium(II) supramolecular complex with cucurbituryl of composition {[Ca(H₂O)₃(HSO₄)(CH₃OH)]₂(C₃₆N₂₄O₁₂H₃₆)}(HSO₄)₂ · 4H₂O is obtained by slow diffusion of methanol into a calcium(II) solution in 2 M H₂SO₄; its crystal structure is determined by X-ray diffraction analysis. The crystals are triclinic, a = 10.4030(9) Å, b = 11.936(1) Å, c = 15.119(1) Å, = 69.829(6)°, = 72.019(5)°, = 70.171(7)°, V = 1618.1(2) ų, space group P , Z = 1, _calcd = 1.754 g/cm³. The crystal structure is a pseudohexagonal packing of {[Ca(H₂O)₃(HSO₄)(CH₃OH)]₂(C₃₆N₂₄O₁₂H₃₆)}²⁺ cylinders shifted by half translation along the a axis. The cylinders are linked via hydrogen bonds, with the crystallization water molecules and HSO^– ₄ anions arranged in the channels.     

1A1⇔5T2 Spin Transition in Heterometallic Solid Phases FexNi1-x(Htrz)3(NO3)2 · H2O (Htrz = 1,2,4‐Triazole)

Solid phases Fe_xNi_1-x(Htrz)₃(NO₃)₂ · H₂O (0.4 x 0.8$) and Ni(Htrz)₃(NO₃)₂ · H₂O were synthesized and studied. The phases were studied by means of magnetochemistry, powder Xray difraction analysis, and electronic and IR spectroscopy. The heterometallic phases are described by the stoichiographic method of differentiating dissolution (DD). The values of x were determined by two methods — atomic absorption and DD. Magnetochemical data showed that the solid phases exhibit a hightemperature ¹A₁ ⁵T₂ 0.5 x 0.8 and disappears at x = 0.4. The spin transition is accompanied by thermochromism (color changed from pink to white at 0.6 x 1 and from pink to light lilac at x = 0.5). A decrease in x leads to a decrease in the temperature of the forward (under heating T_c ) and reverse (under cooling T_c ) transitions, a decrease in hysteresis value ( T_c), and a smearing of the spin transition.     

Novel tetrahedral and heteronuclear transition metal clusters prepared via single and double isolobal displacements

Ten transition metal cluster complexes with parent and substituted cyclopentadienyl ligands, [(⁵-C₅H⁴ CH₂CH₂)₂O][MFeCoS(CO)₈]₂ (2 M=Mo; 3 M=W), (⁵-C₅H₅)(⁵-RC₅H₄)MFeNiS(CO)₅ (5 M=Mo, R=Me; 6M= W, R=H), (⁵-C₅H₅)[⁵-C₅H₄C(O)CH₂]₂[WFeNiS(CO)₅][WFeCoS(CO)₈] (8), (⁵-C₅H₅)₂[⁵-C₅H₄ C(O)CH₂]₂[WFeNiS(CO)₅]₂ (9), (⁵-RC₅H₄)[(⁵-C₅H₄CH₂CH₂)₂O][Mo2FeS(CO)₇][MoFeCoS (CO)₈] (10R=MeCO; 12 R=MeO2C), (⁵-RC₅H₄)₂[(⁵-C₅H₄CH₂CH₂)₂O][Mo₂FeS(CO)₇]₂ (11 R=MeCO; 13 R=MeO2C), were synthesized through single and double isolobal displacements and characterized by elemental analyses, i.r., 1H-n.m.r. and MS techniques.     

Products of Hydrothermal Treatment of Selenite in Potassium Chloride Solutions

Selenite was boiled in KCl solutions of different concentrations at the respective boiling temperatures and atmospheric pressure. The products were subjected to X-ray diffraction analysis, qualitative infrared analysis, differential thermal analysis and microscopic examination. The product obtained in 1.0 M KCl solution was the -form of calcium sulphate hemihydrate (-CaSO₄·0.5H₂O). In more concentrated KCl solution (1.5, 2.0, 2.5, 3.0, 3.5 or 4.0 M), the -form of calcium sulphate hemihydrate (-CaSO₄·0.5H₂O) was formed, and a reaction took place between KCl and CaSO₄, which gave a double salt: potassium pentacalcium sulphate monohydrate (K2SO₄·5CaSO₄·H₂O).This revised version was published online in November 2005 with corrections to the Cover Date.