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Bismuth(III) chloride was found to be highly active as a catalyst for the dehydrochlorination of poly(vinylchloride).The degree of dehydrochlorination was 97percent at the highest.The catalyst showed high activity even in water vapor.

Fe(III) chloride hydrate (FeCl3·xH2O) undergoes simultaneous dehydration and dehydrochlorination from its molten phase in the temperature range 100-200°C. The kinetics of these two parallel thermal processes has been studied by both isothermal and non-isothermal methods. Whereas for the dehydration reaction at temperature below 125°C a second order rate model (F2) fits well, a three-dimensional diffusion (D3) model is found to fit better at temperature above 135°C. For the dehydrochlorination reaction an interface growth controlled model of 1/3 order (F 1/3) appears to be the most suitable over a wide range of reaction. Dynamic thermogravimetry reveals two major steps in the temperature range 50-250°C. The first step which corresponds to the loss of about 4 mols of H2O, invariably follows second order kinetics (F2). The second step which is predominantly a process of dehydrochlorination, generally fits mixed diffusion controlled models due to the overlapping with the dehydration process. There is an excellent agreement in results among the isothermal and non-isothermal methods of determining kinetic parameters.

Thermal dehydration and decomposition characteristics of Fe(III) chloride hydrate have been studied by both isothermal and non-isothermal methods. After the initial melting at 35-40°C both dehydration and decomposition of the salt proceed simultaneously at temperature above 100°C. At 250-30°C a stable hydrated Fe(OH)2Cl is formed representing the first plateau region in the TG curve. Around 400°C, a second plateau is observed corresponding to the formation of mostly Fe2O3 which however retains some OH groups and Cl- ions. However, these temperature ranges vary with the TA equipments used. Chemical analysis of the products of decomposition at temperatures above 140°C also gives evidence for the formation of FeOCl which on hydrolysis in water gives FeCl3 in solution. The FT-IR spectra suggest the presence of structural OH groups even for samples calcined at 300-400°C. The XRD patterns of the products of decomposition in the temperature range 160-400°C indicate the presence of β-FeOOH, some unidentified basic chlorides and α-Fe2O3.

The reactions of palladium(II) salts with 2-hydroxyacetophenone N(3)-propylthiosemicarbazone, H2Ap3Pr, are described. The synthesis and spectral characterization of a new triangular, trinuclear palladium(II) complex with the dianion, Ap3Pr2-, are reported. The X-ray crystal structure determination of [Pd(Ap3Pr2)]3·DMF shows it to contain a chair-form hexagon of alternating Pd and S atoms to form a molecular bowl. The spectrophotometric characterization of H2Ap3Pr is also reported.

The kinetics of the gas-phase reactions of chlorine atoms with dichloromethane (CH2Cl2) and D-dichloromethane (CD 2Cl2) was studied using the relative rate method with Cl + CH3Br as the reference reaction. The rate constants for H-abstraction from CH2Cl2 (kH) and D-abstraction from CD2Cl2 (kD) were measured in the temperature range of 298-527 K and at a total pressure of 100 Torr using N2 as a diluent. The temperature dependencies of the rate constants (with the 2σ error limits) are described by the expressions: kH = (8.69 ± 0.82) × 10-12 × exp(-955 ± 20/T) and kD = (6.98 ± 0.91) × 10-12 × exp(-1285 ± 25/T) cm3 molecule-1 s-1. The kinetic isotope effect, described by the ratio kH/kD, was found of 3.8 ± 0.2 at room temperature.

The title compounds, (I) [TiCl3(C5H10O2)(C4H 8O)] [IUPAC name: fac-trichloro(tetrahydrofuran)(D,L-tetrahydrofuran-2-methanol-O,O′) titanium(III)], and (II) [TiCl3(C5H

The main pathways for the formation of HCl in the stratosphere are through the reaction of chlorine atoms with methane and formaldehyde: Cl + CH4 → HCl + CH3. The production of HCl in the reaction of OH and ClO radicals was measured using time-resolved tunable diode laser spectroscopy. OH and ClO radicals were formed from the 308 nm laser photolysis of mixtures containing O3, Cl2, and H2O. The rate coefficient of 1.25 × 10-12 cc/molecule-sec for the reaction at 298 K was derived. This reaction rate corresponded to a branching fraction of 6.5% relative to the currently recommended rate coefficient for the overall reaction, indicating that the reaction has a significant impact on the partitioning of chlorine compounds in the stratosphere.

The Cl2/HBr chain reaction is reinvestigated by using real time state-selected observations of Δν = -1 chemiluminescence from the HCl(ν) products following pulsed laser photolysis of Cl2.These state-selected observation are analyzed with a more complete kinetic treatment to obtain room temperature rate constats for the chain propagation steps and the vibrational deactivation of HCl(ν=1,2) by HBr.The chain propagation rate constants are kR1=(1.02+/-0.15)E-11 and kR2=(1.1+/-0.4)E-15 cm3 molecule-1s-1, respectively , for Cl+HBrHCl(ν)+Br and Br+Cl2BrCl+Cl.Rate constants for vibrational deactivation of HCl(ν=1) and HCl(ν=2) by HBr are kV1=(1.06+/-0.16)E-12 and kV2=(2.09+/-0.50)E-12 cm3 molecule-1 s-1.Relative intensity measurements of the HCl ν=21 and 10 vibrational fluorescence are used to obtain an HCl(ν) product branching ratio, Nν=2/Nν=1=0.40+/-0.06.The kinetic analysis indicates that broad-band observations of infrared chemiluminescence may lead to erroneous rate constant determinations because of vibrational cascade, whereas the detection of the individual vibrational states leads to correct results.

Heterogeneous reaction kinetics of gaseous nitric acid with deliquesced sodium chloride particles NaCl(aq) + HNO3(g) → NaNO 3(aq) + HCl(g) were investigated with a novel particle-on-substrate stagnation flow reactor (PS-SFR) approach under conditions, including particle size, relative humidity, and reaction time, directly relevant to the atmospheric chemistry of sea salt particles. Particles deposited onto aft electron microscopy grid substrate were exposed to the reacting gas at atmospheric pressure and room temperature by impingement via a stagnation flow inside the reactor. The reactor design and choice of flow parameters were guided by computational fluid dynamics to ensure uniformity of the diffusion flux to all particles undergoing reaction. The reaction kinetics was followed by observing chloride depletion in the particles by computer-controlled scanning electron microscopy with energy-dispersive X-ray analysis (CCSEM/EDX). The validity of the current approach was examined first by conducting experiments with median dry particle diameter Dp = 0.82 μm, 80% relative humidity, particle loading densities 4 × 104 ≤ Ns ≤ 7 × 106 cm-2 and free stream HNO3 concentrations 2, 7, and 22 ppb. Upon deliquescence the droplet diameter D d approximately doubles. The apparent, pseudo-first-order rate constant determined in these experiments varied with particle loading and HNO3 concentration in a manner consistent with a diffusion-kinetic analysis reported earlier (Laskin, A.; Wang, H.; Robertson, W. H.; Cowin, J. P.; Ezell, M. J.; Finlayson-Pitts, B. J. J. Phys. Chem. A 2006, 110, 10619). The intrinsic, second-order rate constant was obtained as kII = 5.7 × 10-15 cm3 molecule-1 s-1 in the limit of zero particle loading and by assuming that the substrate is inert to HNO3. Under this loading condition the experimental, net reaction uptake coefficient was found to be γnet = 0.11 with an uncertainty factor of 3. Additional experiments examined the variations of HNO3 uptake on pure NaCl, a sea salt-like mixture of NaCl and MgCl2 (Mg-to-Cl molar ratio of 0.114) and real sea salt particles as a function of relative humidity. Results show behavior of the uptake coefficient to be similar for all three types of salt particles with Dp ～ 0.9 μm over the relative humidity range 20-80%. Gaseous HNO3 uptake coefficient peaks around a relative humidity of 55%, with γnet well over 0.2 for sea salt. Below the efflorescence relative humidity the uptake coefficient declines with decreasing RH for all three sea salt types, and it does so without exhibiting a sudden shutoff of reactivity. The uptake of HNO3 on sea salt particles was more rapid than that on the mixture of NaCl and MgCl2, and uptake on both sea salt and sea salt-like mixture was faster than on pure NaCl. The uptake of HNO3 on deliquesced, pure NaCl particles was also examined over the particle size range of 0.57 ≤ Dp ≤ 1.7 μm (1.1 ≤ Dd ≤ 3.4 μm) under a constant relative humidity of 80%. The uptake coefficient decreases monotonically with an increase in particle size. Application of a resistance model of reaction kinetics and reactant diffusion over a single particle suggests that, over the range of particle size studied, the uptake is largely controlled by gaseous reactant diffusion from the free stream to the particle surface. In addition, a combined consideration of uptake coefficients obtained in the present study and those previously reported for substantially smaller droplets (Dd ～ 0.1 μm) (Saul, T. D.; Tolocka, M. P.; Johnston, M. V. J. Phys. Chem. A 2006, 110, 7614) suggests that the peak reactivity occurs at a droplet diameter of ～0.7 μm, which is immediately below the size at which sea salt aerosols begin to notably contribute to light scattering.

The reaction products of gaseous TiCl4 with ammonia were TiCl4*5NH3 at 200 deg C, TiCl4*5NH3, TiClN, and NH4Cl at 250-400 deg C, TiCl4*5NH3, TiClN, TiNx, and NH4Cl at 450-650 deg C, TiNx and NH4Cl at 700-1000 deg C, and TiNx, NH4Cl, and HCl at 1100-1400 d

By means of chemical vapor transport methods (900 → 700°C) using HCl as transport agent FeGeO3, Fe2GeO4 and MnGeO3 have been prepared. Co2GeO4 and Fe2GeO4 as well as CoGeO3 and FeGeO3 form continuous crystalline solid solutions, whereas in MnO/CoO/GeO2 two different phases (MnxCo1-x)GeO3 are formed. All of these systems show congruent transport behaviour. Chemical vapor transport has been proved a suitable method to prepare solid solutions.

The IR spectroscopy of HCl adsorbed on silica and on silicalite and of HCl-B (B = (CH3)2O, (CH3CH2)2O, THF) adducts formed in silicalite channels at a??210 K is described in detail. The whole subject is divided in three parts. The first part concerns the IR study of the HCl interaction with silica and silicalite. The formation of weak H-bonded adducts between silanols and HCl molecules has been observed; the number of HCl molecules in the adducts increases with the HCl dosage. The HCl molecules adsorbed on silicalite behave as partially hindered rotators. The experimental results are supported by ab initio and molecular dynamics calculations. In the second part, the IR study of HCl-B complexes (B = (CH3)2O, (CH3CH2)2O, THF, and benzene) either adsorbed on silica or entrapped in silicalite channels is described. In the third part, the results obtained for HCl-B adducts in silicalite are compared with those obtained in cryogenic matrixes and in solution. It is inferred that the acid strength of HCI is appreciably influenced by the presence of the siliceous framework. This result allows discussion of the effect of long-distance interactions (framework effect) on the acid strength of structural Brnsted sites of zeolites. ? 1998 American Chemical Society References and Notes.

The infrared chemiluminescence method of Smith and co-workers is adapted to fast flow reactor conditions where a sensitive infrared detector views the vibrationally excited products of various generating reactions through a circularly variable filter in the absence or presence of added quencher molecules.The initial υ-distributions are found to be totally unrelaxed vibrationally but thermalized rotationally.This allows the experimental measurement of vibrational relaxation rates of high υ levels hitherto inaccessible.The modified Stern-Volmer method of analysis is described in detail.Its reference process is the rapid pumping rate constant 3 s-1 out of the field of view.HCl is generated by any one of four H atom reactions (with Cl2, ICl, ClNO, or SOCl2) or two Cl atom reactions (with HI or HBr), and its quenching rates by CO2 or N2O are m,easured.Quenching probabilities from about 5*10-3 to 0.5 per gas-kinetic collisions for υ=1 to 7 are found for both gases.The results are compared with the limited published data.Detailed discussion is deferred until the following paper which presents data for 18 additional quenchers.

Rotationally resolved infrared emission of HCl was detected with a step-scan Fourier-transform spectrometer in a laser-initiated reaction of Cl+CH3SH. The average rotational energy and its fraction of partition derived, Er=8.2±0.9 kJ mol-1 and r=0.10±0.01, were much greater than the previous results. The difference in vibrational excitation was consistent with a difference in predicted H-Cl bond distances in transition structures of these reactions. The time-resolved Fourier-transform spectra demonstrated improved temporal resolution and detection sensitivity in determining internal-state distributions of products from bimolecular reactions.

The reactions of H atoms with methane, four chlorinated methanes, and isobutene have been studied experimentally using the discharge flow/resonance fluorescence technique over wide ranges of temperatures. The rate constants were obtained in direct experiments as functions of temperature. The experimentally obtained activation energies of the reactions of H atoms with chlorinated methanes demonstrate a correlation with the enthalpies of the reactions. Transition state theory reaction models were created on the basis of ab initio calculations, the Marcus expression for correlation between reaction barriers and reaction energetics, and analysis of experimental data. It is demonstrated that the formalism based on the Marcus expression adequately describes the observed temperature dependencies of the rate constants of the overall reactions. According to the models, abstraction by H atoms of hydrogen atoms from chloromethanes is an important process accounting for significant fractions of the overall rate constants. The models result in expressions for the rate constants of Cl and H atom abstraction channels and the corresponding reverse reactions over wide ranges of temperatures.

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Branching in the gas-phase reaction H + DCl -> HD + Cl (I) (termed abstraction) and -> HCl + D (II) (exchange) has been measured by monitoring the atomic products Cl and D by resonantly enhanced multiphoton ionization.The collision energy has been varied in the range 1.0 - 2.4 eV by alteration in the photolytic source of H.Within the error limits, the cross section for abstraction was found to remain constant at 0.16 +/- 0.06 Angstroem2.The cross section for exchange exhibited a moderate decrease from 0.6 +/- 0.3 to 0.2 +/- 0.1 Angstroem2 with increasing collision energy.These findings concerning the abstraction reaction agree with the results of a quasi-classical trajectory computation, reported here, on the GQQ potential energy surface, the most reliable PES available .The experimental findings for exchange, however, stand in marked contrast to the trajectory results, suggesting that the exchange channel of the GQQ PES may be deficient in the region of high collision energies where the reacting system, en route to exchange, accesses bent intermediate configurations for which ab initio data are lacking.

The kinetics of the reactions between anhydrous HCl and trans-[MoL(CNPh)(Ph2PCH2CH2PPh2) 2] (L=CO, N2 or H2) have been studied in thf at 25.0°C. When L=CO, the product is [MoH(CO)(CNPh)(Ph2PCH2CH2PPh2) 2]+, and when L=H2 or N2 the product is trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh 2)2]. Using stopped-flow spectrophotometry reveals that the protonation chemistry of trans-[MoL(CNPh)(Ph2PCH2CH2PPh2) 2] is complicated. It is proposed that in all cases protonation occurs initially at the nitrogen atom of the isonitrile ligand to form trans-[MoL(CNHPh)(Ph2PCH2CH2PPh 2)2]+. Only when L=N2 is this single protonation sufficient to labilise L to dissociation, and subsequent binding of Cl- gives trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh 2)2]. At high concentrations of HCl a second protonation occurs which inhibits the substitution. It is proposed that this second proton binds to the dinitrogen ligand. When L=CO or H2, a second protonation is also observed but in these cases the second protonation is proposed to occur at the carbon atom of the aminocarbyne ligand, generating trans-[MoL(CHNHPh)(Ph2PCH2CH2PPh 2)2]2+. Addition of the second proton labilises the trans-H2 to dissociation, and subsequent rapid binding of Cl- and dissociation of a proton yields the product trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh 2)2]. Dissociation of L=CO does not occur from trans-[Mo(CO)(CHNHPh)(Ph2PCH2CH2PPh 2)2]2+, but rather migration of the proton from carbon to molybdenum, and dissociation of the other proton produces [MoH(CO)(CNPh)(Ph2PCH2CH2PPh2) 2]+.

Decabenzylferrocene reacts with acetyl chloride in the presence of Al2Cl6 to form Deca(4-acetylbenzyl)ferrocene Fe2 (2).The X-ray structure confirms the all-para-substitution of the ten benzylligands by the acetyl group. 2 crystallizes in the space group P21/n with a=1479.8(3) pm, b=1700.9(4) pm, c=1618.7(8) pm, β=89.99(2) deg and V=4074(2)*10-30 m3.The final refinement resulted in R=0.0936 for 3983 observed reflections with Fo 2?(Fo).Keywords: Iron; Ferrocene; Bulky ligands; Friedel-Crafts-Acylation

Rotational state resolved center-of-mass angular scattering and kinetic energy release distributions were analyzed from experimental velocity-map ion images of the HCl (v′=0, j′=0-6) products of the reaction of chlorine with n-butane. It was shown that th

A new class of nontoxide glasses with the general composition CsAXY//2 (A equals Al, Ga; X equals S, Se; Y equals Cl, Br) has been isolated and characterized. Raman spectroscopy, investigations of the infrared multiphonon edge, and differential thermal analysis measurements show that these glasses contain a giant polymeric tetrahedra-based anion and have good resistance to devitrification. Their chemical durability in a normal atmosphere is very poor and severely affects their optical properties, especially in the infrared multiphonon region.

Titanium dioxide (TiO2) nanoparticles were synthesized by the oxidation of titanium tetrachloride (TiCl4) in a modified diffusion flame reactor. The reactor utilized a multiport diffusion type burner composed of 5 concentric tubes. The flame configuration was (Ar + TiCl4)/Ar/H2/O2/air producing several tens of grams of TiO2 nanoparticles per hour. Flame characteristics of the diffusion flame at the modified burner outlet were investigated. TiCl4 concentration and flow rates of combustion gases such as oxygen, hydrogen and air were chosen as key experimental variables for the control of the particle size and phase composition. TiO2 nanoparticles ranged from 10 to 30 nm in average particle diameter, and the mass fraction of anatase synthesized was 40 to 80% in all experiments.

The reaction of Cp′ReCl4 (Cp′ = EtMe4C5) with 2-3 equiv of bis(trimethylsilyl)sulfide in chloroform in the presence of an oxidant results in the formation of Cp′Re(η2-S3)Cl2, 2. Complex 2 has been characterized by spectroscopic methods, and its structure has been confirmed by an X-ray diffraction study. Complex 2 reacts with hydrogen under mild conditions to form H2S, HCl, and a rhenium product tentatively identified as (Cp′Re)2S4, 3. Complex 3 reacted with benzyl bromide to form [(Cp′Re)2(μ-S2) (μ-SCH2Ph)2]Br2, 4 which has been completely characterized by spectroscopic studies and an X-ray crystal structure. The structures and reactions of the Cp′Re derivatives with sulfur ligands are compared to those of the related tetrasulfur-bridged CpMo derivatives.

The matrix isolation technique, combined with infrared spectroscopy and theoretical calculations, has been used to characterize the products of the photochemical reactions of aniline, anisole, and N,N-dimethylaniline with CrCl2O2. While initial twin jet deposition of the reagents did not lead to product formation, new bands were noted following irradiation with light of λ > 300 nm. In the reactions of CrCl2O2 and aniline, irradiation led to HCl formation, very likely accompanied by CrClO2(H)NC6H5 formation, and a mixture of isomers of CrCl2O-aminocyclohexa-2,4-dienone via oxygen atom transfer. CrCl2O2 and aniline were also codeposited as cryogenic thin films, producing new bands. Irradiation of these films led to further growth of these bands. The same products were identified in the thin film studies as were observed in the argon matrix experiments. The irradiation of the matrices containing CrCl2O2 and anisole and N,N-dimethylaniline were shown to lead to oxygen atom transfer, forming complexes between the corresponding cyclic ketone derivatives and CrCl2O. The identification of the complexes were supported by density functional calculations at the B3LYP/6-311G++(d,2p) level and isotopic labeling (in the case of aniline).

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A series of hydrogen-bonded networks was prepared incorporating ditopic, tritopic, or tetratopic polyamidinium tectons and linear pentiptycene dicarboxylates. The ditopic amidinium forms a 1D hydrogen bonded chain when combined with the pentiptycene tecton, while the tritopic trigonal planar amidinium tecton forms a 2D honeycomb network. A tetratopic amidinium tecton forms a 3D diamondoid network, which is 32-fold interpenetrated, tied for the highest degree of interpenetration observed for a hydrogen bonded network. The bulky pentiptycene functionality prohibits the polymers from packing efficiently, leading to voids within each structure. These frameworks were envisaged as potential molecular motors, but unfortunately, a lack of stability to solvent removal precluded an investigation of these properties.

Near UV irradiation of aerated solutions of (Et4N) 2[CuCl4] in dichloromethane causes the decomposition of CH2Cl2, as evidenced by the buildup of HCl, C 2H2Cl4, and peroxides. A net reduction to [CuCl2]- occurs in the early stages, but is later reversed. In CH2Cl2, [CuCl4]2- is in equilibrium with [Cu2Cl6]2-, and only the latter species is photoactive. The decomposition is initiated by the photodissociation of chlorine atoms, which propagate to peroxy radicals, CHCl2OO. Experimental evidence, including a linear dependence of the decomposition rate on the incident light intensity and on the fraction of light absorbed by [Cu2Cl6]2-, is consistent with a mechanism in which CHCl2OO is reduced by electron transfer from [CuCl2]-, following which protonation yields CHCl 2OOH. The hydroperoxide accumulates during irradiation and it too can reoxidize [CuCl2]-. The quantum yield for HCl production at the outset of irradiation at 313 nm is 1.3 mol/einstein, based on the fraction of light absorbed by [Cu2Cl6]2-.

Abstract: An estimate is made of the limiting values of electrical conductivity, the degree of dissociation, and the thermodynamic dissociation constants of hydrogen chloride in n-alcohols in the temperature range of 278–328?K with a step of 10?K. Multilevel modeling is used to develop model equations for estimating electrical conductivity and dissociation constants on the basis of solvents in a wide range of solution temperatures. Reliable and reproducible results are obtained with a high degree of reliability and reliability.

String of Fe(III), Cu(II), Zn(II) and Zr(IV) complexes were synthesized with tetradentateamino Schiff base ligand derived by condensation of ethylene diamine with gemifloxacin. The novel Schiff base (4E,4′E)-4,4′-(ethane-1,2-diyldiazanylylidene)bis{7-[(4Z

The desire to develop a benign burn rate modifier for propellants has accentuated polymeric carbon nitride (gCN) as a potential candidate for the thermal decomposition of ammonium perchlorate (AP). Here, we have synthesized composites of leaf-shaped CuO and gCN via a facile sonochemical approach. From DSC analysis, the addition of gCNCuO1 reduced the decomposition temperature of AP by 59°C and increased the heat release by ~ 1.4 times that of pure AP. The kinetics of AP decomposition was well investigated via in-situ TG-MS technique. From evolved gas analysis evolution of NO, Cl, HCl, N2O/CO2, NO2 and Cl2 fragments were detected. The quantitative interpretation of kinetic parameters for AP decomposition was done using Coats-Redfern method and the normalization of E values were carried out by applying Kinetic Compensation Correction (KCC). After normalization, E values were decreased by 17 ?kJ/mol and 18 ?kJ/mol for the first and second stages respectively.

The assembly of hydrogen bonded cages using amidinium?carboxylate hydrogen bonding interactions was investigated. A new tris-amidinium hydrogen bond donor tecton based on a tetraphenylmethane scaffold was prepared and its self-assembly with the terephthalate anion studied, and a new tricarboxylate hydrogen bond acceptor tecton was synthesised and its assembly with the 1,3-benzenebis(amidinium) hydrogen bond donor explored. In both cases, molecular modelling indicated that the formation of the cages was geometrically feasible and 1H NMR spectroscopic evidence was consistent with interactions between the components in competitive d6-DMSO solvent mixtures. DOSY NMR spectroscopy of both systems indicated that both components diffuse at the same rate as each other, and diffusion coefficients were consistent with cage formation, and with the formation of assemblies significantly larger than the individual components. An X-ray crystal structure showed that one of the assemblies did not have the desired cage structure in the solid state.

The thermal oxidation etching assisted g-C3N4 nanosheets/CuO was prepared through a facile co-precipitation strategy. In this work, the structure, morphology, and composition of g-C3N4 (UCN, prepared by urea), g-C3N4 nanosheets (TCN, prepared by thermal oxidation etching of UCN), g-C3N4/CuO (UCN/CuO), g-C3N4 nanosheets/CuO (TCN/CuO) were characterized via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Furthermore, the catalytic effect of the obtained samples on the thermal decomposition of ammonium perchlorate (AP) was examined by thermal gravimetric analysis (TGA). As a result, in the case of 5 wt% TCN/CuO, the high decomposition temperature of AP decreased by 120.6 °C, which is much lower than that of UCN, TCN, CuO and UCN/CuO. In addition, the exothermic heat released from the decomposition of AP increased from 430.64 J g?1 to 2856.08 J g?1. This evident catalytic activity may be related to the synergistic effect of CuO and TCN. This work provides a novel strategy for the construction of composite catalyst for the thermal decomposition of AP, which is supposed to possess significant potential in the solid propellant field.

The trapping of classical hydrogen pseudohalides (HX, X = pseudohalogen = CN, N3, NCO, NCS, and PCO) utilizing a phosphorus-centered cyclic biradicaloid, [P(μ-NTer)]2, is reported. These formal Br?nsted acids were generatedin situas gases and passed over the trapping reagent, the biradicaloid [P(μ-NTer)]2, leading to the formation of the addition product [HP(μ-NTer)2PX] (successful for X = CN, N3, and NCO). In addition to this direct addition reaction, a two-step procedure was also applied because we failed in isolating HPCO and HNCS addition products. This two-step process comprises the generation and isolation of the highly reactive [HP(μ-NTer)2PX]+cation as a [B(C6F5)4]?salt, followed by salt metathesis with salts such as [cat]X (cat = PPh4,n-Bu3NMe), which also gives the desired [HP(μ-NTer)2PX] product, with the exception of the reaction with the PCO?salt. In this case, proton migration was observed, finally affording the formation of a [3.1.1]-hetero-propellane-type cage compound, an OC(H)P isomer of a HPCO adduct. All discussed species were fully characterized.

Three-dimensionally ordered macroporous (3DOM) CeO2, 3DOM Cr2O3, 3DOM xCr2O3?CeO2 (x (the weight percentage of Cr2O3) = 3.5, 5.5, and 8.0 wt%), and 5.5 wt% Cr2O3/3DOM CeO2 samples were prepared using the polymethyl methacrylate (PMMA)-templating and incipient wetness impregnation methods, respectively. A number of techniques were used to characterize physicochemical properties of the materials, and their catalytic activities were evaluated for the oxidation of trichloroethylene (TCE). These samples possessed a good-quality 3DOM structure and a surface area of 35?47 m2/g. The 3DOM 5.5Cr2O3?CeO2 sample performed the best (the temperature at TCE conversion = 90% = 255 °C at a space velocity of 20,000 mL/(g h)). Effects of water vapor and carbon dioxide on activity of the 5.5Cr2O3?CeO2 sample were also examined. It is observed that partial deactivation induced by H2O introduction of the 5.5Cr2O3?CeO2 sample was reversible, while that induced by CO2 addition was irreversible. Based on the activity data and characterization results, it is concluded that the good catalytic activity and thermal stability of 3DOM 5.5Cr2O3?CeO2 was associated with its high adsorbed oxygen species concentration, good low-temperature reducibility, and strong interaction between Cr2O3 and CeO2. We believe that the 3DOM 5.5Cr2O3?CeO2 catalyst is promising in the application for oxidative removal of chlorinated volatile organic compounds.

CH4 chlorination with Cl2 gas is used for the production of chlorinated products via C–H bond activation in CH4. Due to the high reactivity of Cl2, this reaction can occur spontaneously under UV irradiation or with mild thermal energy even in the absence of a catalyst via a free radical-mediated chain reaction mechanism that undesirably causes excessive chlorination of the CH4 and is thus non-selective. In this work, CH4 chlorination is investigated using HY and MFI zeolites with various Si/Al ratios, by which the reaction is catalytically controlled for selective production of the mono-chlorinated product (CH3Cl). Depending on the framework type, Si/Al ratio of the zeolites, and reaction conditions, different degrees of CH4 conversion, CH3Cl selectivity, and hence CH3Cl yield were achieved, by which systematic relationships between the catalyst properties and performance were discovered. A high aluminum content facilitated the production of CH3Cl with up to ～20 % yield at a high gas hourly space velocity of 2400 cm3gcat?1 h?1 with a CH4/Cl2 ratio of 1 at 350 °C. HY zeolites generally furnished a slightly higher CH3Cl yield than MFI zeolites, which can be attributed to the larger micropores of the HY zeolites that support facile molecular diffusion. With various flow rates and ratios of CH4 and Cl2, the CH4 conversion and CH3Cl selectivity changed simultaneously, with a trade-off relationship. Unfortunately, all zeolite catalysts suffered from framework dealumination due to the HCl produced during the reaction, but it was less pronounced for the zeolites having a low aluminum content. The results shed light on the detailed roles of zeolites as solid-acid catalysts in enhancing CH3Cl production during electrophilic CH4 chlorination.

Copper (Cu) and its oxides are well-known catalysts for thermal decomposition of ammonium perchlorate (AP). Nano Cu/Cu2O dispersed on graphitic carbon nitride (g-C3N4) based nanocomposites were synthesised by single displa

The cycloneophylplatinum(II) complexes [Pt(CH2CMe2C6H4)(κ2-NN′-2-C5H4NCH2-NH-R], R = 2-C6H4OH, 1; R = 3-C6H4OH, 2; R = 4-C6H4OH, 3, and [Pt(CH2CMe2C6H4)(κ2-NN′-2-C5H4NCH=N-2-C6H4OH)], 4, are reported. The structures of 1 and 4 each contain an intramolecular OH··Pt hydrogen bond, while complex 3 contains an intermolecular OH··Pt hydrogen bond and forms a new type of supramolecular polymer. In contrast, the complex [PtCl2(κ2-NN′-2-C5H4NCH=N-2-C6H4OH)], 5, forms a dimer through intermolecular OH··ClPt hydrogen bonding. Reaction of complex 4 with HCl or HBr occurs by oxidative addition to give hydridoplatinum(IV) complexes [PtHX(CH2CMe2C6H4)(κ2-NN′-2-C5H4NCH=N-2-C6H4OH)], 6, X = Cl; 7, X = Br. The sequential formation of isomers of these compounds is interpreted in terms of a proposed reaction mechanism.

A convenient procedure to synthesize highly dispersed Ni1-xPdx alloys has been developed. The procedure is based on thermal decomposition in the reducing atmosphere of specially synthesized multicomponent precursor. The formation of single-phase solid solutions in the entire range of palladium concentrations was confirmed by powder XRD. The alloys have a porous structure composed of grains whose size depends on the synthesis temperature. The study of the catalytic properties of Ni1-xPdx alloys (5 wt% Pd) showed their high activity in the 1,2-dichloroethane decomposition process. After 5 h of catalytic experiment the yield of carbon material was 160 gС/gcat for Ni1-хPdх. This is more than 3 times higher than the yield of reference samples (porous Ni, Ni–Co, Ni–Cu). The carbon material formed has a segmented fibrous structure. It is characterized by high morphological uniformity. The specific surface area of the obtained carbon material is 580 m2/g.

A new route to cycloneophylplatinum(II) complexes is reported and the selectivity of protonolysis of the platinum-aryl and -alkyl bonds has been determined. Reaction of [PtCl2(SMe2)2] with neophylmagnesium chloride gives the binuclear cycloneophylplatinum(II) complex [Pt2(CH2CMe2C6H4)2(μ-SMe2)2], 1, which is shown to exist as a mixture of syn and anti isomers. Complex 1 reacts reversibly with SMe2 to give [Pt(CH2CMe2C6H4)(SMe2)2], 2, and irreversibly with bidentate ligands NN = 3,4,7,8-tetramethyl-1,10-phenanthroline (phen?) or 4,4′-di-t-butyl-2,2'bipyridine (bubipy) to give the corresponding complexes [Pt(CH2CMe2C6H4)(phen?)], 3, and [Pt(CH2CMe2C6H4)(bubipy)], 4, respectively. Complex 2 reacts with HCl initially by cleavage of the aryl-platinum bond to give mostly trans-[PtCl(CH2CMe2Ph)(SMe2)2], which then rearranges to an equilibrium mixture with trans-[PtCl(C6H4-2-t-Bu)(SMe2)2], while 3 and 4 react to give [PtCl(CH2CMe2Ph)(phen?)] and [PtCl(CH2CMe2Ph)(bubipy)], which do not undergo the isomerization reaction. The protonolysis reactions occur by way of a platinum(IV) hydride complex in each case, and the unusual reactivity of complex 2 is attributed to the ease of dissociation of the Me2S ligands.

The chlorination of Si?H bonds often requires stoichiometric amounts of metal salts in conjunction with hazardous reagents, such as tin chlorides, Cl2, and CCl4. The catalytic chlorination of silanes often involves the use of expensive transition-metal catalysts. By a new simple, selective, and highly efficient catalytic metal-free method for the chlorination of Si?H bonds, mono-, di-, and trihydrosilanes were selectively chlorinated in the presence of a catalytic amount of B(C6F5)3 or Et2O?B(C6F5)3 and HCl with the release of H2 as a by-product. The hydrides in di- and trihydrosilanes could be selectively chlorinated by HCl in a stepwise manner when Et2O?B(C6F5)3 was used as the catalyst. A mechanism is proposed for these catalytic chlorination reactions on the basis of competition experiments and density functional theory (DFT) calculations.

Hydrogen-bridged bis(silylene) complexes of ruthenium and iron were synthesized as the first examples of this type containing Group 8 metals and their rare four-membered ring structures and multi-center bonding interactions at the M-Si-H-Si moiety were clarified by NMR spectroscopy, X-ray crystallography and theoretical calculations.

The new organic-inorganic compound, [C6H7N2O2]3TeCl5·2Cl was synthesized and its structure was determined at room temperature in the triclinic system (P?1) with the following parameters: a?=?10.5330(11)??, b?=?10.6663(11)??, c?=?15.9751(16)?, α?=?82.090(2)°, β?=?71.193(2)°, γ?=?68.284(2)° and Z?=?2. The final cycle of refinement led to R?=?0.057 and Rw?=?0.149. The crystal structure was stabilized by an extensive network of N–H?Cl and non-classical C–H?Cl hydrogen bonds between the cation and the anionic group. Several thermal analysis techniques such as thermogravimetric analysis, differential scanning calorimetric analysis and evolved gas analysis were used. We used isoconversional kinetics methods to determine the kinetics parameters. We observe that the decomposition of [C6H7N2O2]3TeCl5·2Cl entails the formation hydrochloric acid of nitroaniline as volatiles. The infrared spectra were recorded in the 4000–400?cm?1 frequency region. The Raman spectra were recorded in the external region of the anionic sublattice vibration 50–1500?cm?1. The optical band gap was calculated from the UV-Vis absorbance spectra using classical Tauc relation which was found to be 3.12 and 3.67?eV.

Hybrid materials with ZnO anchored on carbon black (CB) are fabricated by using the atomic-layer deposition (ALD) technique. The oxygen-containing functional groups on the surface of the CB act as the reactive sites to facilitate stable deposition of ZnO, and further create a unique hybrid structure with a C–O–Zn bond between CB and ZnO. The catalytic performance of the ZnO/CB hybrids for thermal decomposition of ammonium perchlorate (AP, NH4ClO4) is investigated, showing that two exothermic peaks are merged into one and the peak temperature decreases from 432 °C to 295 °C, even lower than that of ZnO (311 °C). The superior catalytic activity of ZnO/CB hybrids is attributed to the fast electron transfer from ZnO to CB and restricted electron recombination in the hybrids, which significantly benefits from the C–O–Zn bond fabricated by the ALD process. The present study provides a new insight into the catalytic mechanism of metal oxide/carbon hybrids, showing promise for catalyst and reaction accelerator applications.

Ruthenium modified cobalt oxides were prepared by (1) impregnating ruthenium chloride hydrate on cobalt oxides, Ru-supported catalysts (Ru/Co3O4), and (2) Ru-doped catalysts (Ru-Co3O4) where the ruthenium ions were added to the precursor solution, by a one-step sol-gel method with cobalt nitrate. The physicochemical properties of the catalysts were characterized by ICP, BET, XRD, HR-TEM, TPR, and XPS analysis. The effects of ruthenium were studied for the total oxidation of vinyl chloride. This Ru modifier was observed to enhance oxygenate formation. The different preparation methods made contributions to the different amounts of Ru4+ on the surfaces of the catalysts while Ru4+ would be in synergy with Co2+ concentration, and this also changed the chemical coordination of oxygen on the surface. Dispersion of Ru oxides on the cobalt oxides surface could not only improve the catalytic activity and stability on steam, but also decrease the amount of chlorinated by-products and increase HCl selectivity.

Pure nanoparticle ammonia borane (NH3BH3, AB) was first prepared through a solvent-free, ambient-temperature gas-phase combination of B2H6 with NH3. The prepared AB nanoparticle exhibits improved dehydrogenation behavior giving 13.6 wt. % H2 at the temperature range of 80-175°C without severe foaming. Ammonia diborane (NH3BH2(μ-H)BH3, AaDB) is proposed as the intermediate in the reaction of B2H6 with NH3 based on theoretical studies. This method can also be used to prepare pure diammoniate of diborane ([H2B(NH3)2][BH4], DADB) by adjusting the ratio and concentration of B2H6 to NH3.

We present a simple and straightforward protocol for hydrochlorination of terminal arylalkynes to vinyl chlorides using hydrogen chloride under mild reaction conditions. This protocol does not involve any metal catalysts or additives. It is simple, inexpensive, and easy to prepare, and exhibits good reaction activity. The hydrochlorination proceeds smoothly to yield unique regioselective products via the Markovnikov addition rule.

The thermal behavior of the β-blocker anti-hypertensive drug propranolol was investigated using thermoanalytical techniques TG-DTA, DSC and the evolved gas analysis by TG-FTIR, providing information regarding thermal stability, decomposition steps, melting point and heat of fusion of the compound. The results pointed for the decomposition in a single mass loss step, after melting. DSC data revealed that cold crystallization occurred in heat-cool-heat cycles, around 165 °C. TG-FTIR presented 1-naphthol, isopropylamine and HCl as principal decomposition products. A tentative mechanism for the thermal behavior of propranolol is presented.

The invention relates to a method for preparing methanesulfonic acid by recycling a byproduct, namely hydrochloric acid. The method is characterized in that a method of hydrogen chloride, chlorine gas, methanesulfonic acid and hydrogen chloride is adopted, and the byproduct, namely the hydrochloric acid is recycled in the preparation process of the methanesulfonic acid to prepare the methanesulfonic acid. The method has the advantages that the byproduct, namely the hydrochloric acid is adopted for preparing chlorine gas and directly reacted with dimethyl disulfide, so that the safety risk and the logistics cost in purchase, transportation and storage of the chlorine gas with severe toxicity can be avoided; the byproduct, namely the hydrochloric acid, which is difficult to sell can be locally digested and utilized, and turned into treasure, so that the byproduct, namely the hydrochloric acid becomes a main raw material for preparing the methanesulfonic acid and the recycling of chlorine element is realized. Simultaneously, leftover manganese dioxide waste after oxidation reaction of potassium permanganate is utilized to prepare manganese chloride, and the manganese chloride can be used for electrolytic manganese, so that the production cost and the safety risk of the methanesulfonic acid are greatly reduced, and two major restricting factors, namely the chlorine gas and the byproduct, namely the hydrochloric acid in the preparation method of the methanesulfonic acid are simultaneously eliminated.

A process is provided for the chlorination of ethane using chlorine as the chlorinating agent to produce ethylene, hydrogen chloride (HC1) and vinyl chloride monomer (VCM).

TeO2 nanoparticle-loaded graphitic carbon nitride hybrids (TeO2NPs/g-C3N4) were successfully prepared by a calcination strategy. Various characterization and detection techniques were used to analyze its structu

β-Amino carbonyl compounds are attractive targets for chemical synthesis, because they are widely used as biologically active compounds and are important synthons for a variety of pharmaceuticals. Nano-manganese hydrogen sulfate was prepared and used as a novel nano-catalyst for the named organic transformation, i.e. Mannich-type reaction of benzaldehyde, aniline, and cyclohexanone in water. Mannich products were obtained in high yields, with excellent diastereoselectivity, and short reaction time in the presence of a catalytic system comprising nano-Mn(HSO4)2 and a surfactant, for example sodium dodecyl sulfate. Use of mild, environmentally benign reaction conditions, low loading, and ready accessibility are the main features of this new catalyst.

Vanadium-nickel mixed oxides supported on TiO2 (anatase) were prepared by wet impregnation using ammonium metavanadate and nickel nitrate aqueous solution. The performance of as-prepared samples in catalytic dichloromethane (DCM) combustion was investigated, and their physicochemical properties were characterized in detail by X-ray diffraction, N2 physisorption, H2 temperature-programmed reduction, NH3 temperature-programmed desorption, and Raman spectroscopy analyses. Results showed DCM combustion activity over V-Ni/TiO2 catalyst was superior to that of V2O5/TiO2 and NiO/TiO2 catalysts. DCM could be completely converted into CO2, HCl, and a little amount of CO over Ni-V/TiO2 catalyst at 350 °C, the toxic by-products, such as CH3Cl, aldehydes and phosgene could not be observed by online IR spectroscopy. The high catalytic activity, selectivity, and stability of V-Ni/TiO2 catalyst could be due to the good oxidative dehydrogenation ability (ODH), the good reducibility of active oxygen species, and suitable strength of Lewis acidic sites upon introduction of nickel oxide.

Unactivated MCM-41 mesoporous silica catalyzes the photodecomposition of chloroform to phosgene and hydrogen chloride under near-UV (λ > 360 nm) irradiation. The rate of photodecomposition increases toward an asymptotic limit as the O2 partial pressure is increased. Deuterochloroform does not decompose under the same experimental conditions. Low concentrations of both cyclohexane and ethanol quench the photodecomposition, whereas water, up to its solubility limit, does not. Dissolved tetraalkylammonium salts suppress photodecomposition. The data are consistent with a mechanism in which light absorption by an SiO2 defect yields an electron-deficient oxygen atom, which then abstracts hydrogen from chloroform. The resulting CCl 3 radicals react with oxygen to form a peroxy radical that decomposes, eventually yielding phosgene and hydrogen chloride. Unmodified MCM-41 silica catalyzes the photodecomposition of chloroform under near-UV irradiation. It is proposed that decomposition is initiated through hydrogen abstraction from chloroform at a photoactive SiO2 defect site.

Dehydration of lactic acid was performed over various metal sulphates. BaSO4 was found to show an efficient activity for dehydration of lactic acid to acrylic acid due to the moderate acidity on its surface. Under the optimal conditions, 99.8% lactic acid conversion and 74.0% acrylic acid selectivity were achieved over the BaSO4 catalyst.

Ru oxide catalysts supported on Ce-Al2O3 with various Ce contents were prepared by wet impregnation with RuCl3 aqueous solution and characterized by XRD, N2 adsorption, TEM/HRTEM, H 2-TPR, Raman and N

The enzyme thioredoxin reductase (TrxR) is attracting much interest as a potential target for cancer therapy. The presence of a selenium atom in the catalytic site makes it sensitive to inhibition by electrophilic molecules, including the AuI complex auranofin [2,3,4,6-tetra-O-acetyl-1-thio- β-D-glucopyranosato-S-(triethylphosphane)gold]. The reactions between auranofin and models of thiol and selenol nucleophiles present in TrxR (PhSH and PhSeH) have been investigated in chloroform and methanol by means of 1H, 31P, and 77Se NMR spectroscopy. In chloroform, auranofin undergoes ligand substitution of the tetraacetylthioglucose moiety by a PhS or PhSe group. The reaction is reversible in both cases, but it is characterized by widely different equilibrium constants (ca. 1 for S and at least 103 for Se). In polar solvents, such as methanol, the reaction is more complex, and the phosphane moiety also undergoes ligand exchange. Some features have been clarified through the investigation of Et3PAuCl. The elementary processes involved have been characterized by DFT calculations. Copyright

Antimalarial compounds ruthenoquine and methylruthenoquine were studied by X-ray absorption spectroscopy both in solid state and in solution, in normal (aqueous or CH2Cl2 solutions) and oxidative (aqueous solution with H2O2, either equimolar or in large excess) conditions, to detect small changes in the coordination sphere of the ruthenium atom. Since changes in the EXAFS spectra of these compounds are quite subtle, a complete procedure was developed to assess the different sources of uncertainties in fitted structural parameters, including the use of multivariate statistic methods for simultaneous comparison of edge energy correction ΔE0 and distances, which can take into account the very strong correlation between these two parameters. Factors limiting the precision of distance determination depend on the recording mode. In transmission mode, the main source of uncertainty is the data reduction process, whereas in fluorescence mode, experimental noise is the main source of variability in the fitted parameters. However, it was shown that the effects of data reduction are systematic and almost identical for all compounds; hence, they can be ignored when comparing distances. Consequently, for both fluorescence and transmission recorded spectra, experimental noise is the limiting factor for distance comparisons, which leads to the use of statistical methods for comparing distances. Univariate methods, focusing on the distance only, are shown to be less powerful in detecting changes in distances than bivariate methods making a simultaneous comparison of ΔE0 and distances. This bivariate comparison can be done either by using the Hotelling's T2 test or by using a graphical comparison of Monte Carlo simulation results. We have shown that using these methods allows for the detection of very subtle changes in distances. When applied to ruthenoquine compounds, it suggests that the implication of the nonbinding doublet of the aminoquine nitrogen in either protonation or methylation enhances the tilt of the two cyclopentadienyls. It also suggests that ruthenoquine and methylruthenoquine are, at least partially, oxidized in the presence of H2O2, with a small decrease in the Ru-C bond length and increase in the edge energy.

Addition of 1 to 6 equiv of LiC6Cl5 to cis-Pt(PEt3)2Cl2 gives the unexpected phosphine ligand C-H bond activation product Pt(PEt3)(κ2-P,C- PEt2CHMe)(C6Cl5) (1). Aqueous HCl addition to 1 gives the previously reported product of the reaction, cis-Pt(PEt 3)2(Cl)(C6Cl5) (2).

Thermolysis of [TiMe2{η5-C5Me 4(CH2CH2CH - CH2)}2] (1) in toluene at 120 °C for 4 h resulted in the formation of the cyclopentadiene ring-tethered titanacyclobutane [TiIV{η 5-C5Me4CH2CH2CH(κ- CH)}2CH2] (2) in virtually quantitative yields. Thermolysis in an NMR tube at 100 °C revealed that initial elimination of methane is followed by addition of one 3-butenyl double bond to a titanocene-methylidene moiety. The formed titanacyclobutane intermediate [Ti{η5-C5Me4(CH2CH 2CH - CH2)}{η5-C5Me 4CH2CH2CH(κ-CH)CH2CH 2(κ-CH2)}] (4) then underwent a metathesis reaction with the pendant 3-butenyl to give 2 and free ethene. Cleavage of Ti-C bonds of 2 with HCl afforded stable ansa-[TiCl2{η5-C 5Me4(CH2)7η5-C 5Me4}] (3). Sunlight photolysis of 1 gave rise to the cyclopentadiene ring-tethered titanacyclopentane [TiIV{η 5-C5Me4(CH2CH2CH(κ- CH)CH2}2] (5), the known product of cycloaddition reactions following the removal of chlorine atoms from [TiCl2{η 5-C5Me4(CH2CH2CH - CH2)}2] with magnesium (as found by Horacek, M.Chem. Eur. J. 2000, 6, 2397).

Thermal decomposition of chlorpromazine hydrochloride (CP?HCl), trifluoperazine dihydrochloride (TF?2HCl) and thioridazine hydrochloride (TR?HCl), and the ruthenium complexes with dimethyl sulfoxide (dmso) of composition [RuCl2(dmso)4] and L[RuCl3(dmso) 3]?xEtOH, L = CP?HCl, TF?2HCl orTR?HCl is described. The phenothiazines are stable to temperature range of 200-280 °C with an increasing stability order of TF?2H Cl 3(dmso)3]Cl?EtOH. The compound crystallizes with one EtOH, evaporating in part at room temperature.

Matrix isolation infrared spectroscopy has been combined with density functional theory calculations to characterize the molecular complex formed between CS2 and HCl. Besides the shifts on the vibrational modes of the CS2 and HCl subunits, the activation of the symmetrical stretching of the CS2 moiety was also observed in the matrix spectra. Additionally, an intermolecular vibrational mode of S=C=S...HCl was detected near 230 cm 1. The bonding properties of the complex have been interpreted by natural bond orbital (NBO) analysis in terms of "donor-acceptor" interactions.

The synthesis of the organotin-and the bis(organostannyl)methane- substituted crown ethers Ph(3-n)XnSnCH2-[13]- crown-4 (1, n = 0; 2, n = 1, X = I; 3, n = 1, X = Cl; 4, n = 1, X = F; 5, n = 2, X = I; 6, n = 3, X = I; 8, n = 3, X = Cl; 9, n = 2, X = Cl) and Ph (3-n)XnSnCH2Sn(X)nPh (2-n)CH2-[13]-crown-4 (10, n = 0; 11, n = 1, X = I; 12, n = 2, X = I; 13, n = 1, X = F; 14, n = 2, X = Cl) as well as of the ditopic complexes 8·LiCl·H2O and Ph2(SCN)SnCH 2-[13]-crown-4·LiSCN (15·LiSCN) are reported. These compounds were characterized by elemental analyses, by 1H, 13C, 19F, and 119Sn NMR spectroscopy, electrospray mass spectrometry, and in the case of 2 and 4 also by 119Sn MAS NMR spectroscopy. Single-crystal X-ray diffraction analyses reveal distorted tetrahedral configurations for the tin atoms in compounds 1, 11 (Sn2), and 12 (Sn2), whereas intramolecular O→Sn interactions (Sn-O = 2.416(2) (6) to 2.471(3) (11, Sn1) A) characterize the molecular structures of compounds 2, 6, 9, and 11 (Sn1), in which the tin atoms display distorted trigonal-bipyramidal configurations. The spatial arrangement of the Sn(1) atom in compound 12 is distorted octahedral (Sn-O = 2.497(3) and 2.649(3) A), while the tin atom in compound 8·LiCl·H2O is also trigonal bipyramidal. In the latter compound there are both intra-and intermolecular O-H...Cl hydrogen bridges. Moreover, the ditopic complexation of cesium fluoride, CsF, lithium iodide, LiI, and lithium chloride, LiCl, by compounds 4 and 6, respectively, as well as of LiCl by compounds 3 and 14, is unambiguously proved by NMR spectroscopy and electrospray mass spectrometry.

Synthesis of SnO2 powder in order to make varistor properties is technologically important. This study aims at examining the process of making nanosized (98.95 - x)SnO2 + 1CoO + 0.05Nb2O5 + xSm2O3 (mol%) (x = 0.05, 0.10, 0.20, 0.50, 1.00 and 2.00) powders using co-precipitation method. Some nanopowders were studied through XRD, SEM and FTIR analyses. The XRD patterns displayed only a tetragonal rutile structure for different molar ratios of samarium oxide (Sm2O3). The mean crystallite size of the sample doped with 0.05 mol% Sm2O3, calcined at 700 °C for 2 h, was about 10 nm. The SEM micrograph of this sample revealed some nanosized spherical particles with a size range of 45-70 nm. The Sm-rich surface prevented the nanoparticles from growing during the calcination at 700 °C.

A new method for destroying silicon tetrachloride has been developed, which based on a microwave plasma jet that operates at atmospheric pressure using hydrogen as work gas. Experiments showed that the silicon tetrachloride was dissociated into silicon an

Vacuum ultraviolet (VUV) photolysis of an HCl/O2 mixture has been carried out to identify HOOCl by the Ne matrix-isolation infrared spectroscopy with the aid of quantum chemical calculations. Newly-observed IR bands at 823, 1363 and 3542 cm-1 are assigned to those of HOOCl on the basis of the isotope shifts with DOOCl and the CCSD(T)/aug-cc-pVDZ calculation. The observed dependence of band intensities on the time of VUV photolysis indicates that HOOCl and HOClO are the photoproducts formed in an early stage. In addition, HOOCl is found to decompose to form HCl in the UV photolysis (λ ≥ 365 nm), which consists with the S1-S0 energy separation estimated by the TDDFT method.

Orthorhombic structural perovskite NdCrO3 nanocrystals with size of 60 nm were prepared by microemulsion method, and characterized by XRD, TEM, HRTEM, SEM, EDS and BET. The catalytic effect of the NdCrO3 for thermal decomposition of

Molecular structures of hexakis(amino)cyclotriphosphazene, N3P3(NH2)6, neutral and cationic forms of hexakis(ethylamino)cyclotriphosphazene, N3P3(NHC2H5)6,

We report a receptor with an encapsulated amine/amide binding site, which binds HCl with high affinity in organic media - the rate of HCl transport through an apolar phase is controlled by the degree of encapsulation of the HCl binding site.

The thermochemistry of chlorinated γ-alumina surfaces is explored by means of density functional calculations as a function of relevant reaction conditions used in experiments and in high-octane fuel production in the refining industry such as hydrocarbon isomerization and reforming. The role of chlorine as a dope of the Bronsted acidity of γ-alumina surfaces is investigated at an atomic scale. Combining infrared spectroscopy and density functional theory calculations, the most favorable location of chlorine atoms on the (110), (100) and (111) surfaces of γ-alumina is found to result either from direct adsorption or from the exchange of basic hydroxyl groups. Moreover, the modification of the hydrogen bond network upon chlorine adsorption is put forward as a key parameter for changing the Bronsted acidity. In a second step, we use a thermodynamic approach based on DFT total energy calculations corrected by the chemical potentials of HCl and H2O to determine the adsorption isotherms of chlorine and the relative surface concentration of hydroxyl groups and chlorine species on the γ-alumina surfaces. The determination of chlorine content as a function of temperature and partial pressures of H2O and HCl offers new quantitative data required for optimizing the state of the support surface in industrial conditions. The mechanisms of chlorination are also discussed as a function of reaction conditions.

Several new 1,1-disubstituted siloles containing substituents on the ring carbon atoms have been synthesized. The new siloles: 1,1-dihydrido-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (5), 1,1-dihydrido-2,5-dimethyl-3,4-diphenylsilole (6), 1,1-dimethoxy-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (7), 1,1-bis(4-methoxyphenyl)-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (8), 1,1-dipropoxy-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (9), and 1,1-dibromo-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (13) were prepared from reactions originating from the previously reported, 1,1-bis(diethylamino)-2,5-bis(trimethylsilyl)-3,4-diphenylsilole (1) or 1,1-bis(diethylamino)-2,5-dimethyl-3,4-diphenylsilole (2). In addition, three other new organosilane byproducts were observed and isolated during the current study, bis(4-methoxyphenyl)bis(phenylethynyl)silane (11), bis(4-methoxyphenyl)di(propoxy)silane (12) and 1-bromo-4-bromodi(methoxy)silyl-1,4-bis(trimethylsilyl)-3,4-diphenyl-1,3-butadiene (14). Compounds 13 and 14 were characterized by X-ray crystallography and 14 is the first 1,1-dibromosilole whose solid state structure has been determined.

The protonation of the dinuclear phosphinito bridged complex [(PHCy 2)Pt(μ-PCy2){κ2P,O-μ-P(O)Cy 2}Pt(PHCy2)] (Pt-Pt) (1) by Bronsted acids affords hydrido bridged Pt-Pt species the structure of which depends on the nature and on the amount of the acid used. The addition of 1 equiv of HX (X = Cl, Br, I) gives products of formal protonation of the Pt-Pt bond of formula syn-[(PHCy2)(X)Pt(μ-PCy2)(μ-H)Pt(PHCy 2){κP-P(O)Cy2}] (Pt-Pt) (5, X = Cl; 6, X = Br; 8, X = I), containing a Pt-X bond and a dangling κP-P(O)Cy2 ligand. Uptake of a second equivalent of HX results in the protonation of the P(O)Cy2 ligand with formation of the complexes [(PHCy 2)(X)Pt(μ-PCy2)(μ-H)Pt(PHCy2){κP- P(OH)Cy2}]X (Pt-Pt) (3, X = Cl; 4, X = Br; 9, X = I). Each step of protonation is reversible, thus reactions of 3, 4, with NaOH give, first, the corresponding neutral complexes 5, 6, and then the parent compound 1. While the complexes 3 and 4 are indefinitely stable, the iodine analogue 9 transforms into anti-[(PHCy2)(I)Pt(μ-PCy2)(μ-H)Pt(PHCy 2)(I)] (Pt-Pt) (7) deriving from substitution of an iodo group for the P(OH)Cy2 ligand. Complexes 3 and 4 are isomorphous crystallizing in the triclinic space group P1 and show an intramolecular hydrogen bond and an interaction between the halide counteranion and the POH hydrogen. The occurrence of such an interaction also in solution was ascertained for 3 by 35Cl NMR. Multinuclear NMR spectroscopy (including 31P-1H HOESY) and density-functional theory calculations indicate that the mechanism of the reaction starts with a prior protonation of the oxygen with formation of an intermediate (12) endowed with a six membered Pt1-X ... H-O-P-Pt2 ring that evolves into thermodynamically stable products featuring the hydride ligand bridging the Pt atoms. Energy profiles calculated for the various steps of the reaction between 1 and HCl showed very low barriers for the proton transfer and the subsequent rearrangement to 12, while a barrier of 29 kcal mol-1 was found for the transformation of 12 into 5.

The invention relates to a process for the preparation of chloromethane from methanol and hydrogen chloride contaminated with Si compounds, the Si compounds being methylchlorosilanes, methoxymethylsilanes and hydrolysis and condensation products thereof, in which some of the Si compounds are removed by condensation from the chloromethane formed and remaining Si compounds are washed out with methanol, the methanol thus obtained and containing Si compounds being used for the further preparation of chloromethane with hydrogen chloride.

This work reported on the thermal decomposition of ammonium perchlorate activated by addition of NiO nanocrystals with different surface areas. NiO samples were characterized by X-ray diffraction (XRD), transition electron microscope (TEM), Brunauer-Emmet