bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Catalytic Degradation Reaction of Polypropylene with Silica–Alumina
Authors: Ishihara Yumiko , Nanbu Hidesaburo , Iwata Chiemi , Ikemura Tadashi , Takesue Tomoyuki 
Published: July 2006

Abstract
A detailed analysis was carried out on the catalytic degradation of polypropylene with silica–alumina, using a glass tube reactor (25φ×150 mm) at 180 to 300 °C and a N2 flow rate of 120 ml min−1 over a period of 5 to 120 minutes. The ratio of C/S was from 0.1 to 6.0. The molecular weight of PP decreased slightly at about 160 °C by cationic degradation, but the decrease started at about 200 °C by radical degradation (without catalyst). The main chain of PP was remarkable weakened by the catalytic degradation with silica–alumina. Analysis of degradation products by 13C NMR, FD-MS and variation in chain scission number clearly indicated the catalytic degradation of PP to occur in two stages. The first stage at low temperature is initiated by the addition of a proton released from the catalyst to weak links in the main chain. The second stage at high temperature occurs by attack a low-molecular-weight carbonium ion of the saturated degraded oligomer. These ions are closely involved in the production of irregular structural oligomers and their redegradation.
Mixed-Valence States in TCNQ Salts of 1′,1'″-Dibutyl-, 1′,1'″-Dipentylbiferrocene and Their Mixed Crystals
Authors: Nakashima Satoru , Sano Hirotoshi 
Published: July 2006

Abstract
Mixed-valence states in TCNQ salts of 1′,1'″-dibutyl-, 1′,1'″-dipentylbiferrocene and their mixed crystals were investigated by Mössbauer spectroscopy. It was found that a valence delocalization of the mixed crystals was affected by the host lattice.
Behavior of the Enthalpies of Dissolution and Formation in the System Silver–Indium
Authors: Badawi Walid Ahmad , M. Oun Ahmed 
Published: July 2006

Abstract
The enthalpy of dissolution in the system Ag–In has been measured at 1100 K in the whole range of composition. The behavior of the enthalpy of dissolution points out the existence of the compound Ag3In in the liquid state. The enthalpy of formation in the range of the γ phase has also been determined at 623 and 773 K. The enthalpy of formation is negative. The partial molar enthalpy of formation of silver is negative but increase with the increase of the composition, and that of indium is negative and decreases with increasing composition. The enthalpy of formation depends insignificantly on the temperature. A pronounced temperature dependence of the enthalpy of formation seemed not to be a general property of all metallic alloys as reported earlier.
Infrared and Raman Studies of the [VO(O2)2F]2− Ion
Authors: Nour E M , El-Sayed A B , Sadeek S A 
Published: July 2006

Abstract
The IR and Raman spectra of Cs2 [VO(O2)2F] are recorded. The spectra are interpreted on the basis of Cs symmetry of the [VO(O2)2F]2− ion. The ν(V=O), νs(O–O), and νas(O–O) are assigned at 950, 890, and 875 cm−1, respectively. The calculated values of the force constants fV=O, fO–O, fV–O, fV–O′, and fV–F are 670, 298, 262, 273, and 248 N m−1, respectively. The band assignments and the force constant values are discussed in view of the bonding and structure of the [VO(O2)2F]2− ion.
Perkin–Markovnikov Type Reaction Initiated with Electrogenerated Superoxide Ion
Authors: Ojima Fumihiro , Osa Tetsuo 
Published: July 2006

Abstract
The cyclic condensation of active methylene compounds such as diethyl malonate, dimethyl malonate, ethyl acetoacetate, or acetylacetone and dibromoalkanes such as 1,2-dibromoethane, 1,3-dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,6-dibromohexane, 1,3-dibromobutane, or 1,4-dibromopentane with electrogenerated superoxide ion was studied electrochemically in N,N-dimethylformamide (DMF) using cyclic voltammetry (CV) and controlled potential macro-electrolysis. The CV shows that electrogenerated superoxide ion reacts with both active methylene compounds and dibromoalkanes in the dissolved oxygen medium. Controlled potential macro-electrolysis of the above components generally yielded cycloalkanes as the main products. In comparison, the chemical method using sodium ethoxide was also carried out. Two reaction mechanisms via the proton abstraction of active methylene compounds with electrogenerated superoxide ion and via the nucleophilic attack of the superoxide ion on dibromoalkanes are presented.
Kinetics and Mechanism of the Reduction of Dodecatungstocobaltate(III) by Iminodiacetate, Nitrilotriacetate, and Ethylenediaminetetraacetate. A Comparative Study of the Reactivity of Different Amine-N-carboxylates
Authors: K. Saha Swapan , Bhattacharya Prabir , Ali Mahammad , Banerjee Pradyot 
Published: July 2006

Abstract
The kinetics of reduction of dodecatungstocobaltate(III) by iminodiacetate (IDA), nitrilotriacetate (NTA), and ethylenediaminetetraacetate (EDTA) have been studied in aqueous solution at 50 °C, 30 °C, and 15 °C respectively. In general, the reactivity of the amine-N-carboxylates is in the order EDTA&gt;NTA&gt;IDA. All the anionic species have been found to undergo oxidation via both a spontaneous and an alkali metal ion-catalyzed pathway, while molecular form of the acids are oxidized only via spontaneous pathway. The rate of oxidation is given by a general expression kox=k°+k[M+]n where kox=kobs/2[L]T([L]T=total concentration of a particular amine-N-carboxylate) and n may have values 1 or 2 depending on the nature of M+. The terms k° and k account for the rate constants of the spontaneous and catalyzed paths respectively. A general trend K+&gt;Na+&gt;Li+ for the catalyzed path has been observed for the oxidation of these amine-N-carboxylates. Reactivities of different species present in the experimental pH range have been evaluated by carrying out experiment at different pH and using these data in appropriate rate expressions. The reactivities (50 °C) of Hida− are k°=4.70×10−5 dm3 mol−1 s−1 and k1=3.44×10−4 dm6 mol−2 s−1 for the spontaneous and Na+ catalyzed paths respectively. For NTA oxidation (30 °C), rates are k10°(H3nta)=1.11×10−3 dm3 mol−1 s−1, k11°(H2nta−, spontaneous)=7.00×10−3 dm3 mol−1 s−1, k11(H2nta−, Na+ catalyzed)=3.50×10−2 dm6 mol−2 s−1, k12°(Hnta2−, spontaneous)=7.20×10−3 dm3 mol−1 s−1, k12(Hnta2−, Na+ catalyzed)=4.01×10−2 dm6 mol−2 s−1. The corresponding reactivities (15 °C) for EDTA oxidation are k20°(H4edta, spontaneous)=6.80×10−3 dm3 mol−1 s−1, k21°(H3edta−, spontaneous)=4.80×10−2 dm3 mol−1 s−1, k21(H3edta−, Na+ catalyzed)=0.48 dm9 mol−3 s−1, k22°(H2edta2−, spontaneous)=0.21 dm3 mol−1 s−1, k22(H2edta2−, Na+ catalyzed)=1.70 dm6 mol−2 s−1, k23°(Hedta3−, spontaneous)=1.71 dm3 mol−1 s−1, k23(Hedta3−, Na+ catalyzed)=30.00 dm6 mol−2 s−1. A plausible mechanism considering an outersphere association between the complex and reductant has been suggested where the alkali metal ions are assumed to act as a bridge between the reactants.
Stopped-Flow Kinetic Investigations of One-Electron Transfer Reactions of Phenothiazines and Their Radical Cations in Aqueous Solution
Authors: Venkatasubramanian Lakshmanan , Maruthamuthu Pichai 
Published: July 2006

Abstract
The kinetics of one-electron oxidation of the protonated forms of phenothiazines namely, chlorpromazine (CPZH+) and promethazine (PMZH+) with the inorganic peroxides, peroxomonosulfate and peroxodisulfate in aqueous medium, were investigated by stopped flow spectrophotometric technique. The reactions of both the phenothiazines obeyed a total second-order kinetics, first-order each with respect to [phenothiazine] and [peroxide]. Both peroxides generated radical cations from the respective phenothiazines by one-electron transfer. The radical cations, CPZH·2+ and PMZH·2+ were found to oxidize ascorbic acid generating the parent compounds, whereas CPZH·2+ alone was able to react with sulfite, thiosulfate and dithionite to regenerate CPZH+. The kinetics of all these reactions were investigated and discussed.
Convenient Synthesis of Cyclic Trithiocarbonates from 1,2- or 1,3-Dihaloalkanes and Sodium Trithiocarbonate in the Presence of Phase-Transfer Catalyst
Authors: Sugawara Akira , Sato Tsukasa , Sato Ryu 
Published: July 2006

Abstract
Cyclic trithiocarbonates, such as 1,3-dithiolane-2-thiones and 1,3-dithiane-2-thiones, were conveniently synthesized by treating 1,2- or 1,3-dihaloalkanes with sodium trithiocarbonate in the presence of a phase-transfer catalyst.
Selective Formation of Ethene from CO Hydrogenation Reaction over In2O3–CeO2, –La2O3, and –Y2O3 Mixed Oxide Catalysts
Authors: Arai Toru , Maruya Ken-ich , Domen Kazunari , Onishi Takaharu 
Published: July 2006

Abstract
CO hydrogenation over mixed oxides of 3A and 4A Groups (Y2O3, La2O3, CeO2, and ZrO2) with 3B Group (Al2O3, Ga2O3, and In2O3) was carried out. The addition of Ga2O3 or In2O3 to Y2O3, La2O3, and CeO2 enhances the formation of light alkenes. An In2O3–CeO2 catalyst shows the highest selectivity (43%) for ethene with the lowest selectivity (0.5%) for ethane in total hydrocarbons produced. The addition of In2O3 to CeO2 results in an increase in activity for the CO hydrogenation reaction. From the results of an ethene hydrogenation reaction over mixed oxide catalysts, the high selectivity for alkene formation over In2O3-containing catalysts is due to a suppression of alkene hydrogenation by the addition of In2O3. Indium in CeO2 is highly dispersed while keeping an oxidation state of +1 or +3 under the reaction conditions.
Effects of Solvent and Temperature on the 1,4-Asymmetric Induction in the Diastereoselective Hydrogenation of Dehydrodipeptides
Authors: Ikeda Satoru , Yamagishi Takamichi , Yamaguchi Motowo , Hida Mitsuhiko 
Published: July 2006

Abstract
A study of the effets of solvent and temperature on the stereoselectivity of asymmetric hydrogenation of dehydrodipeptides has been made with Rh(I)–(DPP-AE) catalyst, in which an electrostatic interaction is possible between the dimethylamino group of the ligand and the carboxyl group of the substrate. The highest stereoselectivity was attained in the MeOH–water solvent, while aprotic solvents such as DMF and THF gave comparatively low selectivity and reactivity. With increasing the temperature from −40 °C to 80 °C in alcoholic solvent, the stereoselectivity increased to reach a maximum at 20–40 °C, then decreased. The effects of solvent and temperature on the stereoselectivity were discussed.
Facile Preparation of Optically Active Bicyclo[3.3.1]nonane-2,6-diol and 3,3,7,7-Tetramethylbicyclo[3.3.1]nonane-2,6-diol by Enzyme-Catalyzed Hydrolysis, and Enantiomer Recognition Behavior of Crown Ethers and Podands Having These Diols as a Chiral Subunit
Authors: Naemura Koichiro , Matsumura Takahisa , Komatsu Masanori , Hirose Yoshiki , Chikamatsu Hiroaki 
Published: July 2006

Abstract
Hydrolysis of 2,6-diacetoxybicyclo[3.3.1]nonane (5) using lipase from Candida cylindracea gave (+)-(1S,2R,5S,6R)-6-acetoxybicyclo[3.3.1]nonan-2-ol (4) with 81% e.e. and (−)-(1R,2S,5R,6S)-5 with 95% e.e., and pig liver esterase-catalyzed hydrolysis of 2,6-diacetoxy-3,3,7,7-tetramethylbicyclo[3.3.1]nonane (9) afforded (−)-(1S,2R,5S,6R)-3,3,7,7-tetramethylbicyclo[3.3.1]nonane-2,6-diol (7) with 96% e.e. and (+)-(1R,2S,5R,6S)-9 with 86% e.e. By lithium aluminum hydride reduction, (+)-4 and (−)-5 were converted to (+)-bicyclo[3.3.1]nonane-2,6-diol (3) and (−)-3 with high optical purity, respectively, and (+)-7 was obtained from (+)-9. Using these optically active diols 3 and 7 as a chiral subunit, optically active crown ethers and podands were prepared and their enantiomer recognition behavior was evaluated by the enantiomer differential transport of (±)-1,2-diphenylethylamine and methyl ester of (±)-phenylglycin hydrochloride through bulk liquid membrane.
Efficient Reduction of Triphenylmethanol to Triphenylmethane by 9,10-Dihydro-10-methylacridine in the Presence of Perchloric Acid
Authors: Ishikawa Masashi , Fukuzumi Shunichi , Goto Tatsushi , Tanaka Toshio 
Published: July 2006

Abstract
Reduction of triphenylmethanol (Ph3COH) to triphenylmethane by an NADH model compound, 9,10-dihydro-10-methylacridine (AcrH2), proceeds very efficiently in the presence of perchloric acid (HClO4) in acetonitrile at 298 K via hydride transfer from AcrH2 to triphenylmethyl cation (Ph3C+) which is formed by the dehydration of Ph3COH with HClO4. Mechanisms of hydride transfer reactions from NADH model compounds to Ph3C+ are also discussed.
Preparation of Optically Pure α-Alkyl β-Hydroxy Nitriles by the Bakers’ Yeast Reduction
Authors: Itoh Toshiyuki , Fukuda Tsuneyasu , Fujisawa Tamotsu 
Published: July 2006

Abstract
The bakers’ yeast reduction of 2-alkyl-3-oxobutyronitrile gave optically pure 2-alkyl-3-hydroxybutyronitriles. Especially 2-phenyl-3-oxobutyronitrile gave only syn diastereomer of 2-phenyl-3-hydroxybutyronitrile in high optical yield.
Photoelectrochemical Properties of Thin Films of Zinc Porphyrin Derivatives with Pyridyl Group
Authors: Takahashi Kohshin , Komura Teruhisa , Imanaga Hiroto 
Published: July 2006

Abstract
The cathodic photocurrents of the film electrodes of ZnPyP3P(3) and ZnPyP3P(4), (PyP3P(n), 5-(2-, 3-, and 4-pyridyl)-10,15,20-triphenylporphyrin, where (n) denotes the position of free bond of pyridyl group), were almost four times larger than that of ZnTPP (TPP, 5,10,15,20-tetraphenylporphyrin) in 0.01 mol dm−3 quinhydrone aqueous solution at pH 5. On the other hand, the very small anodic photocurrent was observed with the film electrodes of ZnTPyP(3) and ZnTPyP(4) (TPyP(n),5,10,15,20-tetra(2-, 3-, and 4-pyridyl)porphyrin). The photoelectrochemical properties of ZnPyP3P(2) and ZnTPyP(2) were distinct from those of other structural isomers, but approximately similar to those of ZnTPP. The conductivities of ZnPyP3P(n) films were about three oders of magnitude larger than those of ZnTPP and ZnTPyP(n) films. It was found from the absorption and resonance Raman spectra that the pyridyl group in porphyrin coordinated to zinc in another porphyrin in the solid films as well as in toluene and dichloromethane solutions. The molecular arrangement of zinc porphyrin in the solid film probably influenced the photoelectrochemical properties and the conductivity.
Analysis of Cyclic Voltammograms for Polypyrrole-as-Deposited Pt/poly[tris(4-vinyl-4′-methyl-2,2′-bipyridine)ruthenium(II) perchlorate] Electrodes
Authors: Murao Kenji , Tanaka Naoki , Suzuki Kazuhiro 
Published: July 2006

Abstract
Oxidation waves in cyclic voltammograms (CVs) observed during repeated potential cyclings of polypyrrole-as-deposited Pt/poly-1 electrodes (poly-1: poly[tris(4-vinyl-4′-methyl-2,2′-bipyridine)ruthenium(II) perchlorate]) in 0.1 M TBAP/acetonitrile, that lead to the bilayer (BL) electrochemistry, have been quantitatively analyzed. As the potential cycling is repeated, the CV change occurs, i.e., decrease of the peak current and positive shift of the peak potential. This is shown to be the result of logarithmic decrease in the complementary charge transfer coefficient β in the totally irreversible thin-layer (TITL) electrochemistry. kTL° (standard rate constant for polypyrrole oxidation) and CTL° (initial concentration of the reduced sites in polypyrrole) have been determined to be 5.50×10−9 cm mol−1 s−1 and 3.15×10−3 mol cm−3, respectively, by fitting CV data to the theory of the TITL model. The subsequent onset and growth of the CV waves in the higher potential region are explained as being due to progressive partitioning of polypyrrole sites from the TITL mode to the BL mode in which polypyrrole sites are oxidized. The partition coefficient θ, defined as the ratio of polypyrrole sites oxidized in the BL mode to all the polypyrrole sites, has been found to approximately depend on the logarithm of β. In the BL mode, a linear relationship is found between peak current and peak potential. Simulation of the CV waves has been performed based on the theoretical models of TITL and BL electrochemistry, and has revealed that a model assuming separation of polypyrrole sites into the TITL and BL modes prior to each cyclic sweep explains the occurrence of the significantly separated current peaks in both modes. These results are discussed in terms of Electrochemically driven Phase Separation (ECPS), in which the decrease in β is directly related to the separation of the mixed poly-1 and polypyrrole phase.
Methanol-Incorporated Photoaddition of N-Methyl-9,10-phenanthrenedicarboximide to Alkenes. Addition at Carbonyl and Phenanthrene-Ring Carbon Atoms
Authors: Kubo Yasuo , Nanba Mikako , Hayashi Etsuko , Araki Takeo 
Published: July 2006

Abstract
Irradiation of acetonitrile–methanol (2:1 v/v) solutions of N-methyl-9,10-phenanthrenedicarboximide (3) with alkenes 5a–g gave methanol-incorporated adducts (9c–f) at a carbonyl carbon atom in 3, those (10c,f) at a phenanthrene-ring carbon atom, and a methanol-adduct 11g to alkene 5g, together with products 4, 6b,e–g, 7b,e–g, and 8e,f obtained by the photoreactions in benzene. The concentration effect of alkenes 5e,f on yields of products 6e,f, 7e,f, 8e,f, 9e,f, and 10f showed that both 9e,f and 10f arose from a relatively short-lived singlet excited state of 3. The values of the free-energy change associated with an electron transfer (ΔGet) from alkenes 5a–d,g to the singlet excited state of 3 and fluorescence quenching rate constants support a photochemical electron transfer mechanism for the methanol-incorporated addition. Both LiClO4 and BU4NClO4 caused only slight decreases in the relative ratios 10c/9c indicating that both the methanol-incorporated addition at the phenanthrene-ring carbon atom and that at the carbonyl carbon atom might arise from a contact ion pair state. The fact that the methanol-incorporated addition at the arene-ring carbon atom was observed only in the reaction of 3 in a series of N-methylarenedicarboximides, possessing a five-membered imide ring, is interpreted on the basis of the spin density of the radical anions of the imides derived from the photochemical electron transfer.
Homologation of the Side Chain of 2-Nitrotoluene. Synthesis of a Tryptophan Precursor
Authors: Tanaka Hideo , Murakami Yasuo , Torii Sigeru 
Published: July 2006

Abstract
2-(2-Nitrophenyl)-1,3-propanediol (2) was selectively converted to 2-(2-nitrophenyl)propenal (3) by the use of a mixture of dicyclohexylcarbodiimide (DCC) and dimethyl sulfoxide in benzene, while 2-nitrobenzoic acid was obtained by the oxidation of the diol 2 with sodium periodate in the presence of a catalytic amount of ruthenium dioxide or with chromic acid. The enal 3 was subjected to further transformation to afford a potent tryptophan precursor and some useful indole derivatives.
Synthetic Photochemistry. XLVI. Cycloaddition of exo, endo-2,7-Bis(methoxycarbonyl)-11,12-dioxatetracyclo[6.2.1.13,6.02,7]dodeca-4,9-diene and Conjugated Enones and p-Quinones
Authors: Tian Guan Rong , Mori Akira , Kato Nobuo , Takeshita Hitoshi 
Published: July 2006

Abstract
Photocycloaddition of exo,endo-2,7-bis(methoxycarbonyl)-11,12-dioxatetracyclo[6.2.1.13,6.02,7]dodeca-4,9-diene with conjugated enones and p-quinones occurred exclusively at the exo-addition moiety to give [2+2]cycloadducts. From cyclohexenone, all four possible photoadducts were obtained. A single photoadduct from cyclopentenone was a cis-transoid-cis isomer. Upon thermolysis, cyclobutene derivatives were formed from these photoadducts. An acid treatment of oxetane derivatives derived from photoadducts of p-quinones afforded Michael adducts instead of dienone–phenol rearrangement products.
Crystal Structure of an 8,5′-Iminocarbonyloxy-Bridged Guanine Nucleoside Methanol Solvate
Authors: Minamoto Katsumaro , Shiomi Niro , Kondo Kazumoto , Eguchi Shoji , Honda Masako , Katayama Chuji , Katayama Atsushi , Tanaka Jiro 
Published: July 2006

Abstract
The crystal structure of 8,5′-[(allylimino)carbonyloxy]-2-N-dimethylaminomethylene-9-(2′,3′-O-isopropylidene-β-d-ribofuranosyl)guanine (2a) methanol solvate was determined by X-ray analysis. Its base-sugar torsion angle conforms to the CD spectral behavior of the partially deprotected compound 2b in the sense of anti-conformation.
Regioselective Reaction of Oxiranes with S-Phenyl Thioesters Catalyzed by Quaternary Onium Salts or Crown Ether–Metal Salt Complexes
Authors: Iizawa Takashi , Goto Akira , Nishikubo Tadatomi 
Published: July 2006

Abstract
Regioselective addition reactions of 2-substituted oxiranes with S-phenyl thioesters gave 2-aceyloxy-1-phenylthio derivatives in high yield using some 18-crown-6–metal complexes as well as tetrabutylammonium salts as a catalyst under relatively mild conditions.
Methylviologen-Accelerated Photoreduction of Tris(acetylacetonato)cobalt(III) with 1-Benzyl-1,4-dihydronicotinamide
Authors: Yamashita Kohichi , Kajiwara Shûta , Ohkubo Katsutoshi 
Published: July 2006

Abstract
The photoreduction of tris(acetylacetonato)cobalt(III) (Co(acac)3) by 1-benzyl-1,4-dihydronicotinamide (BNAH) was examined with or without methylviologen in the wavelength range of 340–410 nm. The reaction rate of electron transfer from BNAH to Co(acac)3 was considerably enhanced by methylviologen, especially, in lower polar environments; The weaker the hydrophobic interaction between BNAH and the substrate become, the more effectively methylviologen acts as an electron mediator for the above photoreaction. The reaction mechanism is also discussed with particular reference to the participation of the electron mediator in the elementary steps of the present photoinduced reaction.
Prediction of Soil Sorption Coefficients of Hydrophobic Organic Pollutants by Adsorbability Index
Authors: Okouchi Shoichi , Saegusa Hisayoshi 
Published: July 2006

Abstract
The adsorbability index proposed by Abe et al. to predict the activated carbon adsorption of organic compounds from aqueous solution was well correlated with the soil sorption coefficients of polycyclic aromatic hydrocarbons (PAHs), alkylbenzenes, chlorobenzenes, chlorinated alkanes and alkenes, heterocyclic and substituted PAHs, and halogenated phenols. The adsorbability index was also found to be well correlated with the first-order molecular connectivity index and the total molecular surface areas of these compounds.
XPS Study of Binuclear Mo(V) Complexes with Di-μ-oxo, μ-Oxo-μ-sulfido, and Di-μ-sulfido Bridges
Authors: Takahashi Hideaki , Shibahara Takashi , Yamamoto Yoshihisa 
Published: July 2006

Abstract
X-Ray photoelectron spectroscopy (XPS) was applied to three binuclear molybdenum(V) complexes of di-μ-oxo-, μ-oxo-μ-sulfido-, and di-μ-sulfido-bis[(cysteinato)oxomolybdate(V)]2−, [Mo2(μ-O)x(μ-S)yO2(cys)2]2− (x=2, y=0; x=y=1; and x=0, y=2), and the electronic state for Mo atom of the (μ-O)2 bridge, (μ-O, μ-S) bridge and (μ-S)2 bridge complexes was studied. It has been found that the binding energy of the Mo 3d5⁄2,3⁄2 peaks shifts to a lower value by at most 0.5 eV with increasing the number of μ-S bridges from 0 to 2. On the other hand, those of O 1s, C 1s, N 1s, and S 2s peaks are not significantly affected by bridge substitution. The change in the electronic state of Mo atoms is discussed in terms of the low electronegativity of the S atom.
Solubilities and Dissolution States of a Series of Symmetrical Tetraalkylammonium Salts in Water
Authors: Nakayama Haruo , Kuwata Hiromi , Yamamoto Norikazu , Akagi Yutaka , Matsui Hiroshi 
Published: July 2006

Abstract
The solubilities of a series of symmetrical tetraalkylammonium salts, R4NX (R=CH3–n-C8H17, including i-C4H9 and i-C5H11; X=Cl, Br, I, NO3, and ClO4), in water have been determined over the temperature range between 5 and 45 °C. The solubilities of these salts were found to be strongly dependent upon both the chain length of R of the R4N+ cation and upon the partial molar volume of the X− anion. It has been concluded that these solubilities are closely related with the stability of a “cage-like” water structure, which is presumably formed around the R4N+ cation in the solution. A thermodynamic interpretation of the solubility of the R4NX salts was made by using some thermodynamic properties obtained by a differential scanning calorimetry, together with the enthalpy of the solution calculated from the temperature dependence of the solubility.