bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics and Mechanism of Reduction of Hexacyanoferrate(III) by Sodium Tetrahydroborate
Authors: Bhattacharjee Mitra , Bhattacharjee Apurba K , Mahanti Mahendra K 
Published: July 2006

Abstract
A kinetic investigation of the reduction of hexacyanoferrate(III) by sodium tetrahydroborate in buffered aqueous solution has been carried out. The rate of the reaction is proportional to the concentration of both, tetrahydroborate and hydrogen ions. The effect of the addition of some inorganic salts has been studied. The temperature has been varied, and the Arrhenius parameters have been evaluated. The rate of hydrolysis of tetrahydroborate has been separately studied. It has been observed that the activation energies for both the reactions—the reduction of hexacyanoferrate(III) and the hydrolysis of tetrahydroborate—are equal. A plausible mechanism for the reduction of hexacyanoferrate(III) has been proposed.
The Rate Constants of the Reactions of Hydrogen and Oxygen Atoms with Fluoroethylenes
Authors: Sugawara Ko-ichi , Okazaki Kiyoshi , Sato Shin 
Published: July 2006

Abstract
The pulse-radiolysis technique combined with the atomic resonance absorption method was used for the measurement of the room-temperature rate constants of the reactions of hydrogen and oxygen atoms with fluoroethylenes. The rate constants obtained at 298±2 K are as follows, in units of 10−12 cm3 molecule−1s−1 (1 cm3molecule−1 s−1=6.022×1017 m3 mol−1s−1). The standard deviation is within 10%.
(Remark: Graphics omitted.)
The correlation between the rate constants and the reactivity index calculated by the INDO method is discussed.
Pressure Effects on the Reaction of Hydroxide Ion with Sodium 2-Bromoethanesulfonate
Authors: Asano Tsutomu , Okada Toshio 
Published: July 2006

Abstract
Kinetic effect of pressure on the reaction of hydroxide ion with 2-bromoethanesulfonate was studied. The reaction was moderately accelerated by pressure and the activation volumes suggest that the presence of the negative charge on the sulfonato group does not produce any measurable solvation increase during activation.
The Separation of Aluminium Trichloride and Iron Trichloride by Selective Hydrogen Reduction
Authors: Shoji Yuichi , Matsuzaki Ryoko , Saeki Yuzo 
Published: July 2006

Abstract
When a gaseous mixture generated by heating a mixture of AlCl3 and FeCl3 (&lt;19wt%) was introduced, with a hydrogen stream, into a reaction zone held at various temperatures, the iron content in the sublimate decreased markedly above 300 °C; AlCl3 containing less than 10ppm of iron was obtained at 600 °C.
The Reductive Coupling of Organic Halide Using Hydrazine and a Palladium Catalyst. II. Homocoupling of 1-Iodoalkanes
Authors: Nakajima Riichiro , Morita Kazuhiro , Hara Tadashi 
Published: July 2006

Abstract
The hydrogenolysis and dimerization of iodoalkanes were catalyzed by Pd in the presence of an appropriate reducing agent. Hydrazine was found to be effective for the coupling of 1-iodoeicosane to give tetracontane, C40H82, in a 74% yield. The yield of the coupling product decreased with the decrease of the number of the carbon atoms in the 1-iodoalkanes. Both alkylhydrazines and alkenes were shown not to take part in the reaction as a reaction intermediate.
The Synthesis of New Electron Acceptors, 9,10-Bis[cyano(ethoxycarbonyl)methylene]-9,10-dihydroanthracene and 10-[Cyano(ethoxycarbonyl)methylene]-9-anthrone
Authors: Nogami Takashi , Kanda Yasuhiro , Tanaka Hidekazu , Mikawa Hiroshi 
Published: July 2006

Abstract
We synthesized two new electron acceptor molecules. Their electron affinities were estimated by measuring the charge-transfer absorption spectra with three donor molecules in a 2-methyltetrahydrofuran solution. The former molecule was estimated to have an electron affinity comparable to 1,3,5-trinitrobenzene, and the latter, to m-dinitrobenzene.
A Convenient Synthesis of 3-(Diethoxymethyl)alkanals
Authors: Saigo Kazuhiko , Okagawa Shuji , Nohira Hiroyuki 
Published: July 2006

Abstract
3-(Diethoxymethyl)alkanals were obtained in moderate yields by the diisobutylaluminium hydride reduction of ethyl 3-(diethcxymethyl)alkanoates, which were simply synthesized in one pot by the copper (II)-catalyzed reaction of ethyl diazoacetate with 1-trimethylsiloxy-1-alkenes, followed by the ring cleavage of the resulting cyclopropanes with concentrated sulfuric acid in the presence of triethyl orthoformate.
Preparation of Dl-Alanine by the Reaction of (±)-2-Chloropropionic Acid with Aqueous Ammonia under Pressure
Authors: Ogata Yoshiro , Inaishi Morio 
Published: July 2006

Abstract
The effects of experimental conditions (molar ratio of reactants, concentration, temperature, and pressure) on the yield of Dl-alanine produced by the reaction of (±)-2-chloropropionic acid with aqueous ammonia have been studied. Molar ratio of NH3: CH3CHClCO2H (ca. 10:1) much lower than that reported in the literature (68:1) can give a comparable yield (ca. 78%) by the reaction under pressure at 70 °C for 5 h, a much shorter time than that reported in the literature (over 96 h). Addition of ammonium carbonate does not increase the yield against the literature.
Theory of Molecular Deformation Due to the Vibronic Interaction between Two Closely-spaced Electronic Levels. II. Green’s Function Treatment
Authors: Nishikawa Kiyoshi , Kimura Minoru , Aono Shigeyuki 
Published: July 2006

Abstract
Vibronic interaction between two closely-spaced electronic levels was investigated by use of the temperature Green’s function. A Green’s function version for the mean field approximation was derived which is capable of reproducing results obtained in the preceding work. The spectrum of phonon in the normal phase was then calculated and the critical (strictly speaking, characteristic, since we are dealing with a finite system) temperature Tc was obtained where the phonon becomes completely soft causing lattice distortion. The fluctuation effect was investigated and the mean field theory was examined for its applicability. When the level spacing is comparable to or larger than the value of the electron-phonon coupling constant, the mean field theory is satisfactory, but when the two levels are nearly degenerate, it is not so good because the problem in question is in the regime involving extremely strong coupling.
Thermal Decomposition Studies of Ammonium Heptamolybdate(6–) Tetrahydrate by Means of High-temperature Oscillating X-Ray Diffraction with a Rotating Anode Type Large Capacity Generator
Authors: Isa Kimio , Ishimura Hajime 
Published: July 2006

Abstract
Ammonium heptamolybdate(6–) tetrahydrate (AHM) was studied by means of high temperature oscillating X-ray diffraction with a large capacity generator of 12 kW. Experimental conditions were determined precisely. It was possible to settle the maximum value of diffracted patterns, and the inherited error was about 1.5%. Thermal decomposition of AHM was studied by means of TG-DTA, but the first decrease of TG could not be explained as a single process of decomposition. Moreover it could also not be explained by means of high-temperature oscillating X-ray diffraction with a standard generator. However, with a large capacity generator, the first decrease of TG could be explained to be a convolution of three steps of decomposition. Moreover, the second and third steps could be explained by observing the microscopic structural change. In a high-temperature oscillating XRD, (heating rate 2 °C/min), a peak temperature of 96 °C was recognized, which had not been reported before. Also from 110 °C to 226 °C, a row of the small peak has been found. Finally, the first stage of decomposition which was thought to be a single step in the experiment of TG-DTA, could be seperated into three steps. Moreover, the onset and offset temperatures of changes of characteristic diffraction intensity are determined. It was proved that high-temperature oscillating X-ray diffraction is a powerful analysing method in thermal analysis.
The Phosphorescence Spectra of Methyl-substituted 9,10-Anthraquinones in Solutions at 77 K
Authors: Kuboyama Akira , Matsuzaki Sanae Y 
Published: July 2006

Abstract
The phosphorescence spectra and their lifetimes of 9,10-anthraquinone and its 2-methyl and 2,3-dimethyl derivatives in various kinds of glassy solutions at 77 K have been obtained. In the non-hydrocarbon solutions, 2-methylanthraquinone shows, in most cases, a dual phosphorescence, consisting of a nπ* phosphorescence and a ππ* phosphorescence with different lifetimes, while 2,3-dimethylanthraquinone shows a very broad ππ* phosphorescence spectrum. The quinone-solvent interactions and the relative positions of the close-lying 3nπ* and 3ππ* levels of these quinones are discussed on the basis of the experimental results.
Kinetics and Mechanism of 1,4-Cycloaddition between Tetracyanoethylene and Styrenes. II. Effect of Para Substituents
Authors: Uosaki Yasuhiro , Nakahara Masaru , Osugi Jiro 
Published: July 2006

Abstract
The 1,4-cycloaddition of TCNE to p-methyl-, p-chloro-, and p-bromostyrenes by way of the EDA complex has been studied in chloroform at 25 °C by the spectrophotometric method. The Hammett correlation obtained from the kinetic data provides −5.5±0.2 as the reaction constant ρ. The negative value is large in magnitude relative to other common 1,4-cycloadditions, suggesting some large partial charges in the rate-determining transition state. A linear correlation between the logarithmic forms of the reaction rate and the EDA-complex formation constant is in favor of the reaction scheme where the complex is on the pathway of the cycloaddition.
A Theoretical Approach to the Dielectric Relaxation of Alcohol Solutions. II. The Effect of Dilution with Inert Solvents on the Principal Relaxation Times of Primary Alcohols
Authors: Minami Ryuichi , Itoh Koichi , Takahashi Hiroaki , Higasi Keniti 
Published: July 2006

Abstract
The concentration dependence of the principal relaxation times, τp, of primary alcohol/inert solvent solutions are analyzed based on the equation,
τp=2(1+KxA)τH,
where xA is the alcohol mole fraction, K the equilibrium constant corresponding to the formation of hydrogen bonded multimers, and τH the time constant characterizing the rotational activation process of the terminal OH groups of the multimers. By applying Eyring’s absolute rate theory to the activation process, we calculated τP as a function of temperature and alcohol concentration. The results reproduce quite well the τP values observed for the ethanol/cyclohexane, 1-hexanol/cyclohexane, and 1-propanol/benzene solutions.
The Application of Polarization Coherent Anti-Stokes Raman Spectroscopy to the Line-shape Analysis of Liquid Sample
Authors: Igarashi Ryosaku , Iida Fumisato , Hirose Chiaki , Fujiyama Tsunetake 
Published: July 2006

Abstract
The polarization CARS spectra were observed for a few typical Raman lines at various experimental settings. Based upon the observed and calculated spectra, the usefulness and the validity of the polarization CARS method for the study of the overlapped Raman lines observed for a condensed system have been emphasized.
Kinetic Studies of the Electron Transfer Reactions in Iron(II) and Iron(III) Systems. XI. Electron Transfer Reaction between Aquairon(II) and Tris(1,10-phenanthroline)iron(III) in Water Mixed with Methanol, Ethanol, 1-Propanol, and Ethylene Glycol
Authors: Wada Goro , Takahashi Kumiko , Isobe Masako 
Published: July 2006

Abstract
The electron transfer reaction Fe2+aq+Fe(phen)33+→Fe3+aq+Fe(phen)32+ has been investigated in order to find out the influence of the dielectric nature of media on the reaction rates, by the method of stopped-flow spectrophotometry. As the reaction media, were used aqueous mixtures with various alcohols, such as methanol, ethanol, 1-propanol, and ethylene glycol at their various mole fractions x. The second-order rate constant k grows larger approximately linearly with the increase in x, in a sequence: methanol&lt;ethylene glycol&lt;ethanol&lt;1-propanol. When In k is plotted against D−1 (the reciprocal dielectric constant), all points come together on a single straight line with a positive slope, indifferent to the kinds of the alcohols used. This fact suggests that the reaction proceeds through three successive elementary processes, Fe2+aq+Fe(phen)33+\overseti→[Fe(H2O)62+·Fe(phen)33+]\oversetii→[Fe(H2O)63+·Fe(phen)32+]\oversetiii→Fe3+aq+Fe(phen)32+, in which Process i is the formation of an outer-sphere ion-pair between two reacting ions, Process ii the intramolecular electron transfer in the intermediate complex, and Process iii the separation of the ion-pair into the product ions, the last being the rate-determining step. The reaction scheme is compared with that of the reaction Fe2+aq+Fe(OH)2+→Fe(OH)2++Fe2+aq, where the first step of the ion-pair formation is rate-determining.
Equilibrium and Structure of Deprotonated Bis(glycylglycinato)copper(II) in Aqueous Solution
Authors: Nakasuka Noriyuki , Makimura Kenya , Kajiura Hiroko 
Published: July 2006

Abstract
Potentiometric titration was carried out at 25.0±0.1 °C and at an ionic strength of 1.00 mol dm−3 in sodium perchlorate for a system of copper(II)–dipeptide(A)–a second ligand(B) in an aqueous solution to obtain the formation constants of mixed ligand complexes CupHqArBs. A was glycylglycine or glycinamide, and B was ethylamine or 2-aminoethanol. The structure of CuH−1A2 in solution is discussed. It was found that the ligand A acts as a unidentate ligand and the other deprotonated H−1A as a terdentate one for the most part; only about 2% of this complex are in a bidentate-bidentate form.
Multiple Paths for Photo-methylation and -methoxylation of Methyl 2-Pyridinecarboxylate in Methanol
Authors: Sugiyama Toru , Furihata Toshikazu , Takagi Kyoko , Sato Michitsugu , Akiyama Shinya , Satô Gen P , Sugimori Akira 
Published: July 2006

Abstract
UV-irradiation of methyl 2-pyridinecarboxylate in methanol in the absence of added acid brings about methylation at the 5-position via the excitation of C=O of the ester group, while in the presence of added acid the 4-position of the pyridine ring is methylated. In the presence of sulfuric acid methoxylation via an excimer is dominant over methylation. In the presence of hydrochloric acid methylation via chlorine atoms becomes dominant.
Application of the Water-gas Shift Reaction. I. Hydrogenation and Hydroformylation Reactions of Olefins with Carbon Monoxide and Water Catalyzed by Rhodium Phosphine Complexes
Authors: Okano Tamon , Kobayashi Teruyuki , Konishi Hisatoshi , Kiji Jitsuo 
Published: July 2006

Abstract
The hydrogenation of methyl crotonate with CO and H2O is efficiently catalyzed by RhH2(O2COH)[P(i-Pr)3]2 or [RhCl(C7H8)]2/P(i-Pr)3/n-BuLi (C7H8=norbornadiene). Both catalyst precursors are shown to form the same active species; transRh(OH)(CO)[P(i-Pr)3]2. The catalytic activity of the system ([RhCl(C7H8)]2/phosphine/n-BuLi) increases with increase of the basicity of the phosphine ligands (phosphine=P(i-Pr)3&gt;P(n-Bu)3&gt;PPh(i-Pr)2&gt;PPh2(i-Pr)&gt;PPh3). This reaction is also applicable to the hydrogenation of the C=C bond of electronwithdrawing olefins and the C=O bond of ketones and aldehydes. Interestingly, the catalysis for the C=C bond, to which less electron-withdrawing groups are attached, gives dominantly aldehydes due to hydroformylation. The mechanism is also discussed.
α,β-Unsaturated Carboxylic Acid Derivatives. XXI A Novel Synthesis of α-Dehydroamino Acid Derivatives by the Arbusov Reaction of α-Phosphoranylideneamino-2-alkenoates
Authors: Shin Chung-gi , Yonezawa Yasuchika , Watanabe Kazuhiro , Yoshimura Juji 
Published: July 2006

Abstract
The reaction of ethyl 2-azido-2-alkenoate with organic tervalent phosphorus reagent gave the corresponding 2-phosphoranylideneamino derivative as an stable intermediate. This transformed gradually at room temperature, or immediately on a silica-gel column to give the corresponding 2-phosphinylamino derivative in a good yield. The Arbusov reaction of the intermediate which occurred during the transformation was found to be applicable for the other azido olefins. The formation mechanism and the configurational determination of the new products are discussed.
Synthesis of Macrocyclic [n.n.n](1,3,5)Cyclophane Polylactones
Authors: Kanishi Masayuki , Kunizaki Jun-ichi , Inanaga Junji , Yamaguchi Masaru 
Published: July 2006

Abstract
A series of new macrocyclic cyclophane polylactones has been synthesized by one-step condensation of the appropriate tri(acid chloride)s and triols using the silver cyanide-promoted esterification procedure.
Restricted Rotation Involving the Tetrahedral Carbon. XL. Barriers to Rotation of 9-(1-Methyl-2-propenyl)triptycenes
Authors: Kikuchi Hiromi , Hatakeyama Shiro , Yamamoto Gaku , Oki Michinori 
Published: July 2006

Abstract
9-(1-Methyl-2-propenyl)triptycenes were prepared by addition of substituted benzynes to 9-(1-methyl-2-propenyl) anthracene or Dields-Alder addition of p-benzoquinone to the anthracene followed by enolization and methylation. The crystals of these compounds were pure or enriched isomers of the possible rotamers but the rotational barriers were too low to obtain every possible isomer in a pure state at room temperature. The barriers to rotation were obtained by both classical and dynamic NMR methods. These values were almost the same when the peri-substituent was either a chloro or a bromo but were definitely lower when the peri-substituent was a methyl or a methoxyl.
Prediction of Adsorption Isotherms of Organic Compounds from Water on Activated Carbons. II. Relative Adsorbabilities of Elements
Authors: Abe Ikuo , Hayashi Katsumi , Kitagawa Mutsuo 
Published: July 2006

Abstract
In order to predict the adsorbability of organic compounds out of water onto activated carbon, the contribution of individual atoms to the adsorbability is calculated. The contribution of the carbon atom is positive, that of nitrogen and oxygen atoms is negative, and that of the hydrogen atom is very small.
A Short-step Synthesis of 4-Hydroxyproline
Authors: Hara Junko , Inouye Yoshinobu , Kakisawa Hiroshi 
Published: July 2006

Abstract
The reaction of N-benzyl-, N-diphenylmethyl-, or N-(1-phenylpropyl)-α-methoxycarbonylmethanimine N-oxide newly prepared with acrylaldehyde in benzene, followed by hydrogenolysis over palladium hydroxide and by acid hydrolysis, gave 4-hydroxyprolines.
The Synthesis of 2,5-Dialkylcyclopentanones from Aliphatic Aldehydes and Formaldehyde
Authors: Watanabe Yoshihisa , Sakamoto Fukashi , Shim Sang Chul , Mitsudo Take-aki 
Published: July 2006

Abstract
Aliphatic aldehydes react with formaldehyde in the presence of dimethylamine hydrochloride at 200 °C to form 2,5-dialkylcyclopentanones in moderate yields. Propanal, butanal, and pentanal give 2,5-dimethyl-, 2,5-diethyl-, and 2,5-dipropylcyclopentanone respectively, but ethanal gives only a tarry material.
Photoelectrochemical Properties of CdSnO3 and LaRhO3 Electrodes in Aqueous Solutions
Authors: Yoneyama Hiroshi , Ohkubo Toshikazu , Tamura Hideo 
Published: July 2006

Abstract
CdSnO3 sinter electrodes work as n-type photoanodes with a high electrochemical stability in alkaline solutions. A thin film LaRhO3 electrode prepared on a substrate platinum plate shows p-type photoresponse in aqueous solutions, giving rise to the hydrogen evolution with a fair stability. The threshold wavelength beyond which no photoresponse appears is ca. 700 nm for the former and 950 nm for the latter electrode.
The Character of Acid Sites on the Gypsum Surface
Authors: Okazaki Susumu , Yamazaki Mituo 
Published: July 2006

Abstract
The maximum value in the number of acid sites per unit of surface area of the gypsum formed in the reaction between Ca(NO3)2 and H2SO4 was observed at the heat-treatment temperature of 200 °C, corresponding to the dehydration temperature for the change from its hemihydrate form to soluble anhydrite. The IR-absorption spectra of the gypsum showed no bands assignable to isolated OH groups or Ca–OH species. The IR spectra of the pyridine adsorbed on the gypsum showed only the bands due to Lewis-acid sites. The gypsum heat-treated at temperatures lower than 500 °C showed catalytic activities for the double-bond isomerization of 1-butene. The cis-/trans- ratio of 2-butene was 2–2.5, showing that the catalytic activity was due to Lewis acid, not to Brönsted acid. The isomerization of cyclopropane to propene was scarcely promoted by the gypsum at 250 °C. This fact is another indication of the absence of Brönsted acid sites on the heat-treated gypsum. Most of the weak Lewis acid sites (H0≤+4.8) were ascribable to exposed Ca2+ ions surrounded by monodentate sulfate ions on the surface of metastable anhydrite III-CaSO4.
The Aluminium(III) Ion-assisted Aquation of the Pentaammine fluorochromium(III) Ion
Authors: Iida Masayasu , Yamatera Hideo 
Published: July 2006

Abstract
The aquation of the pentaamminefluorochromium(III) complex was found to be assisted by the aluminium ion. The observed pseudo-first-order rate constant, kobsd, can be written approximately as: kobsd=kAl[Al3+] (kAl=7.5×10−4 dm3 mol−1 s−1 at 35 °C, pH 3.0, I=2.0 mol dm−3). The rate constant decreased with an increase in the hydrogen-ion concentration, and this hydrogen-ion dependence was explained by assuming that the attack of aluminium ions on CrF(NH3)52+ was blocked by the protonation of the fluoro ligand. The analysis of the experimental results gave 3.0±0.1 for the logarithm of the protonation constant. The effects of ClO4− and Co(CN)63− on the reaction rate were explained by considering the formation of ion-pairs between the anions and the reacting cations.
Kinetics of the Formation of Alkoxy-derived Barium Metasilicate
Authors: Yamaguchi Osamu , Tominaga Kazuhiro , Shimizu Kiyoshi 
Published: July 2006

Abstract
Amorphous BaSiO3 or a mixture of this and BaSiO3·H2O was formed by the simultaneous hydrolysis of barium and silicon alkoxides. The temperature of hydrolysis and the time of aging influence the crystallization of amorphous BaSiO3 into BaSiO3·H2O. The decomposition of BaSiO3·H2O into crystalline BaSiO3 was analyzed by isothermal thermogravimetry. Decomposition isotherms were constructed by the equation −ln(1−α)=kt and the activation energy was determined as 143.5 kJ/mol. The kinetics of crystallization of amorphous into crystalline BaSiO3 was interpreted by the equation 1−(1−α)1⁄3=kt. Activation energies were 276 kJ/mol and 204 kJ/mol for the initial and final stages, respectively.
Synthesis of Four Stereoisomers of γ-Hydroxyarginine via the Corresponding Isomers of γ-Hydroxyornithine
Authors: Mizusaki Koichi , Makisumi Satoru 
Published: July 2006

Abstract
Diastereomeric γ-hydroxy-l- and d-ornithines were prepared by reduction of the corresponding γ-oxoornithines synthesized from l- and d-histidines with sodium borohydride. The isomeric composition of the product obtained from l-histidine was estimated to be 68% erythro and 32% threo isomers and that of the product from d-histidine 65% erythro and 35% threo isomers by automatic amino acid analysis after conversion of the basic amino acids into neutral Nδ-acetyl derivatives. The diastereoisomers of each γ-hydroxyorni thine were separated by chromatography on a Dowex 50 column, four optically active isomers being isolated as their hydrochlorides in crystalline state. Guanidination of these isomers with 1-amidino-3,5-dimethylpyrazole nitrate (ADPN) gave the corresponding optically active isomers of γ-hydroxyarginine which were isolated as crystalline hydrochlorides. Erythro-γ-hydroxy-l-arginine hydrochloride shows a specific rotation which agrees very closely with that of natural product of γ-hydroxyarginine.