bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultraviolet Spectra of Hydrazide Solutions and Their Hydrolysis. II. Hydrolysis of Formhydrazide in Alkaline Solutions
Authors: Mashima Mitsuo , Ikeda Fujiko 
Published: July 2006

Abstract
The aparent first-order rate constants of the base catalyzed hydrolysis of formhydrazide have been determined by ultraviolet absorption measurements. Three cases of hydrolysis applicable to three different ranges of NaOH concentrations were recognized. The activation entropies have been calculated from the change of rate constant with temperature. The effects of solvent basicity and temperature on the absorption spectra have also been studied.
The Crystal and Molecular Structure of Piperazinium Terephthalate, (H2NC4H8NH2)2+(O2C·C6H4·CO2)2−
Authors: Kashino Setsuo , Sasaki Minoru , Haisa Masao 
Published: July 2006

Abstract
Piperazinium terephthalate has been prepared and examined by X-ray analysis. The compound crystallizes in the monoclinic space group P21⁄c with two formula units in a unit cell. The cell dimensions are: a=9.45, b=8.30, c=8.33 Å, and β=117.3°. The structure was determined by the Patterson method from the data collected with CuKα radiation on Weissenberg photographs, and refined by the block-diagonal least-squares method with anisotropic temperature factors for non-hydrogen atoms and fixed isotropic ones for hydrogen atoms. The final R value is 0.108 for 941 non-zero reflections. Acid and base moieties occupy the positions of center of symmetry in the cell. Two N+−H…O− hydrogen bonds (2.612 and 2.737 Å) link a nitrogen atom of piperazine with two carboxyl oxygens of the acids related by c glide plane to form a three-dimensional hydrogen bond network, in which each oxygen atom accepts one hydrogen bond. The coordination around the nitrogen atom is nearly tetrahedral. The piperazine ring takes a chair form. The twisting angle between the carboxyl group and the benzene ring plane is 17.3°.
Molecular Structure of Nortricyclene Studied by Gas Electron Diffraction
Authors: Bohn Robert K , Mizuno Kazumi , Fukuyama Tsutomu , Kuchitsu Kozo 
Published: July 2006

Abstract
The molecular structure of nortricyclene (tricyclo[2.2.1.02,6]heptane) has been studied by gas phase electron diffraction. The average values of the bond distances and their limits of error are: rg(C–C)=1.532±0.003 Å and rg(C–H)=1.114±0.011 Å. It is further shown that rg(C3–C4)=1.554±0.013 Å, rg(C1–C2)+rg(C2–C3)=3.042±0.010 Å, and ∠C1–C7–C4=96.9±0.5°.
Molecular Vibrations and Force Fields of Alkyl Sulfides. VI. Methyl Ethyl Sulfide and Its Deuterated Compounds, and Diethyl Sulfide
Authors: Ohsaku Masaru , Shiro Yuji , Murata Hiromu 
Published: July 2006

Abstract
Deuterated methyl ethyl sulfides, CD3SCH2CH3 and CH3SCD2CD3, were prepared, and their infrared spectra were recorded in the gaseous, liquid, and solid states. The normal coordinates of methyl ethyl sulfide, its deuterated analogues, and diethyl sulfide have been treated by the use of a modified Urey-Bradley potential field. The conformational analyses of these sulfides were made by the aid of the calculations. In the gaseous and liquid states, two forms (T and G) have been confirmed to exist for CH3SCH2CH3, and three forms (TT, TG, and GG), for CH3CH2SCH2CH3. In the solid state, CH3SCH2CH3 or CH3CH2SCH2CH3 exists in one form: T or TT. The observed infrared frequencies were compared with the calculated frequencies and were fully assigned.
Ionic Mobility of Some Inorganic Ions in Mixed Solvents from Electromigration on Paper
Authors: Lahiri M M , Seal B K , Mukherjee S K 
Published: July 2006

Abstract
Measurements of ionic mobilities of a number of cations and anions in nonaqueous and mixed solvents were made from electromigration on filter paper, and the apparent advantages of the ionophoretic method over other modern techniques have been explained. The values so obtained have been corrected for (a) electroosmotic and (b) tortuosity (i.e., ‘added migration path length’) effects, in order to compare them with those in free solution. Considering the combined effect of dielectric constant and viscosity the ionic mobilities obtained by the electrophoretic method are considered to be of correct order of magnitude. The ionic mobilities at constant dielectric constant when plotted against reciprocal of viscosity show a slight deviation from linearity.
Transmission of Substituent Effects through Oxygen and Sulfur Atoms. III. The Ionization Equilibrium Constants of Ring-substituted cis-β-Phenoxyacrylic Acids
Authors: Kajimoto Okitsugu , Kobayashi Masaru , Fueno Takayuki 
Published: July 2006

Abstract
cis-β-Phenoxyacrylic acid and several of its ring-substituted derivatives were prepared, and their ionization constants were determined in 50% ethanol–water at 25 °C. The Hammett ρ value for the ionization of these acids, 0.439, is smaller than that reported for cis-β-phenylthioacrylic acids, 0.531. The greater efficiency of the sulfur atom in transmitting the substituent effects is explainable in terms of the “through-conjugation” of the sulfur atom in the thioacrylate anions formed.
Studies on the Fragment Ion Distribution and Their Reactions by the Use of a Charge Spectrometer. II. The Charge Exchange Reactions in Methanol with Fast Positive Ions
Authors: Nagatani Toshio , Yoshihara Kenji , Shiokawa Takanobu 
Published: July 2006

Abstract
Distribution of fragment ions after bombardment of a methanol molecule with various positive ions has been studied by the use of a double mass spectrometer. It was found that the internal energy distribution function has fine structures. The appearance potentials of the fragment ions were re-estimated. From the results the mass spectra of methanol by electron impact were interpreted fairly accurately. The successive ion-molecule reactions after the charge exchange were studied by increasing pressure in the reaction chamber. The behaviors of the metastable ions were also investigated.
Alkoxy and Phenoxy Bridged Dimeric Copper(II) Complexes with Salicylaldimine Ligands
Authors: Miners J O , Sinn E 
Published: July 2006

Abstract
The tridentate SchifF base N-3-hydroxy-n-propylsalicylaldimine can be coordinated with copper(II) to form three kinds of dimeric oxy-bridged antiferromagnetic complexes (metal: ligand ratio—1: 1), as well as the normal monomeric complex. In one of the dimeric complexes pairs of copper atoms are bridged by pairs of the deprotonated alcoholic oxygens of the ligands. The others have an extra ligand X (X=–Cl, –ONO2) per copper atom, the metals are bridged by phenolic oxygens, the alcoholic hydroxyls are not deprotonated, but are either coordinated (if X=Cl) to five-coordinated copper atoms in discrete dimer molecules, or participate in intermolecular hydrogen bonding linking individual dimeric molecules in which the copper atoms are four-coordinated. In the presence of pyridine, ammonia, or mild inorganic base, a rearrangement reaction can be induced, resulting in conversion of the phenolic-bridged (five-coordinated copper) dimer into the related alcoholic-bridged (fourcoordinated copper) dimer. This behaviour is not followed by N-hydroxyethylsalicylaldimine which appears to form only one kind of copper complex [Cu(Lig)X] (X=–C1, –ONO2); in which the metal atoms are essentially planar and do not take part in strong antiferromagnetic interactions.
Cadmium and Silver Sulfide-impregnated Silicone Rubber Membranes as Selective Electrodes for Cadmium Ions
Authors: Hirata Hiroshi , Date Kenji 
Published: July 2006

Abstract
Silicone rubber membranes impregnated with mixtures of cadmium sulfide and silver sulfide were developed as selective electrodes for cadmium ions in a solution. Both co-precipitated and sintered mixtures could be used as the active materials for the electrode membrane, but here the membrane which contained a mixture in which cadmium sulfide had been added to silver sulfide after they had been precipitated individually did not show the satisfactory response characteristics. The Nernstian slope was obtained in the activity range from 10−1 to 10−5 M Cd2+, while the analytical range was from 10−1 to 10−6 M. These potentials did not change at pH values from 2.5 to 7.5. Among common ions, silver, copper(II), mercury(II), iron(III), sulfide, and iodide ions interfered seriously. About 10–100 times as many lead and bromide ions and more than 1000 times as many alkali metals, alkaline earth metals, zinc, aluminum, nickel, manganese(II), cobalt, nitrate, and perchlorate ions were tolerated in coexistence with cadmium ions.
Polarographic Studies of the Anodic Oxidation of Mercury. I. Anodic Waves of Ammonia and Several Amines in N,N-Dimethylformamide
Authors: Matsui Yoshihisa , Kurosaki Yukio , Date Yoshio 
Published: July 2006

Abstract
The behavior of ammonia and several amines at the dropping mercury electrode was studied in N,N-di-methylformamide containing 0.10m Et4NClO4 by means of DC polarography and amperometric titration. Ammonia gave a diffusion-controlled anodic wave, which was attributed to the reversible oxidation of mercury to the 1:2 complex of mercury(II) with ammonia. A dilute solution of methylamine or dimethylamine gave a diffusion-controlled anodic wave similar to that of ammonia. A concentrated solution of each amine gave a prewave due to the adsorption of the electrolysis product, Hg(am)22+, on the electrode surface. Trimethylamine also gave an anodic wave, but it was attributed to the oxidation of the amine itself to the corresponding cation radical. Ethylenediamine and 1,2-diaminopropane each gave a well-defined anodic wave over the concentration range examined. The wave was diffusion-controlled and was attributed to the reversible oxidation of mercury to the chelate compound of the Hg(diam)22+ type. No adsorption phenomena were observed in this case. Aromatic amines such as aniline and β-naphthylamine gave no anodic waves. The overall stability constants of the 1:2 complexes of mercury(II) with ammonia, methylamine, dimethylamine, ethylenediamine, and 1,2-diaminopropane were evaluated by the analyses of the waves to be 1016.9, 1017.1, 1015.0, 1023.5, and 1024.0m−1 respectively.
Asymmetric Hydrogenation of C=O Double Bond with Modified Raney Nickel. XXVII. Asymmetric Hydrogenation of Acetylacetone
Authors: Tanabe Tadashi 
Published: July 2006

Abstract
The asymmetric (enantioselective) hydrogenation process of acetylacetone (AA), which is a highly enolized compound, was studied by the use of catalysts modified with d-tartaric acid, and l-glutamic acid. AA corroded the Raney nickel catalyst during the hydrogenation. The modification protected the catalyst from corrosion, and the protective effects by the amino acids were greater than that by the hydroxy acid. The modification with tartaric acid increased the hydrogenation velocity of AA, but the amino acid hardly affected the hydrogenation velocity. The glutamic acid on the catalyst surface reacted with AA to form a Schiff base during the hydrogenation. The hydrogenation proceeded mainly by means of a two-step process via 2-pentanol-4-on. The modifying pH and temperature affected the asymmetric activity of the catalyst. In the first step of the hydrogenation, the catalyst modified with d-tartaric acid showed a high asymmetric activity, but the one modified with l-glutamic acid exhibited a low asymmetric activity as a result of the Schiff base formation. In the second step, the modification with d-tartaric acid promoted the formation of racemic 2,4-pentanediol (II), and the l-glutamic acid increased the production of meso II.
A Kinetic Study on the Decomposition of Benzyl N-(Hydroxymethyl)carbamate in Alkaline Solution
Authors: Takeuchi Shigeya 
Published: July 2006

Abstract
The decomposition of benzyl N-hydroxymethylcarbamate (N-BHMC) by potassium hydroxide was carried out in a mixed solvent dioxane-water. The following rate equation was obtained. R0=k[N-BHMC]0[KOH]0, where [N-BHMC]0 and [KOH]0 denote the initial concentrations of N-BHMC and potassium hydroxide, respectively. The equation is analogous to that of Ugelstadt obtained for the hydroiytic decomposition of N-hydroxy-methylbenzamide. Thus the reaction was assumed to proceed via the three steps:
1) C6H5CH2OCONHCH2OH+OH−\ightleftarrowsC6H5CH2OCONHCH2O−+H2O
2) C6H5CH2OCONHCH2O−\ightleftarrowsC6H5CH2OCONH−+CH2O
3) C6H5CH2OCONH−+H2O\ightleftarrowsC6H5CH2OCONH2+OH−
Chemistry of Mixed Transition-metal Complexes. V. The Preparation of Several Mixed Transition-metal Complexes with Two μ-Diphenylphosphido Groups
Authors: Yasufuku Katsutoshi , Yamazaki Hiroshi 
Published: July 2006

Abstract
Several mixed transition-metal complexes with two μ-diphenylphosphido groups as bridging ligands were prepared from bis(diphenylphosphine)metal complexes and diiodometal complexes by means of the action of amine or a Grignard reagent.
Syntheses of Some Cyanine Dyes of Bunte Salt Type
Authors: Yamamoto Masashi , Nakamura Shigeo , Yoshimura Kunio , Yuge Masuo , Morosawa Shiro , Yokoo Akira 
Published: July 2006

Abstract
In order to investigate the photosensitivity of compounds such as photosensitizing dyes of Bunte salt type which have not been synthesized yet, the following compounds were prepared: 1,1′-di-(2-potassiumsulfothio-ethy)-4,4′-tricarbocyanine acetate (VI), 1,1′-di-(2-potassiumsulfothioethyl)-2,2′-tricarbocyanine acetate (VII), 6,6′-dimethyl-3,3′-di-(2-potassiumsulfothioethyl)dithiacarbocyanine acetate (VIII), and 3-(2-bromoethyl)-3′-(sulfothioethyl)-5,6,5′,6′-tetramethoxydithiacarbocyanine (XII).
Branched-Chain Sugars. II. On the Configuration of Branched-Chain Sugars from Methyl 2-O-Benzoyl-4,6-O-benzylidene-α-d-ribo-hexopyranosid-3-ulose
Authors: Yoshimura Juji , Sato Ken-ichi , Kobayashi Kazuhiko , Shin Chung-gi 
Published: July 2006

Abstract
Stereoselectivities in diazomethane and nitromethane reaction of methyl 2-O-benzoyl-4,6-O-benzylidene-α-d-ribo-hexopyranosid-3-ulose were examined. Reduction of the epoxidation product (2) gave an epimeric 3-C-methyl derivative in contrast with that obtained by the Grignard reaction. Comparison of NMR spectra of the corresponding di-O-acetate of the both epimers proved that 2 has the gluco-configuration. Ring-opening of the epoxide with alkali, methanolic ammonia, and acid gave the corresponding 3-C-hydroxymethyl, 3-C-aminomethyl (17), and de-O-benzylidenated product, respectively. Hydrogenation of the 3-C-nitromethyl derivative (21) obtained by nitromethane condensation, in the presence of Raney nickel, accompanied with benzoyl-migration to give 3-C-benzamidomethyl derivative (22). De-benzoylation of 22 with methanolic potassium hydroxide gave 3-C-aminomethyl derivative (26) and an orthoester-type compound. Comparison of 26 with 17 and their derivatives indicated that 21 has the allo-configuration. The both configurations were also supported by the optical rotation of 3-C-benzamidomethyl derivatives in cuprammonium solution.
Optically Active Triptycenes. VI. Optical Resolution of 2,5-Dihydroxy-8-methoxycarbonyltriptycene and Absolute Configuration of 2,5-Dimethoxy-8-methoxycarbonyltriptycene
Authors: Shimizu Yasumi , Naito Taketoshi , Ogura Fumio , Nakagawa Masazumi 
Published: July 2006

Abstract
After several unsuccessful attempts, optical resolution of 2,5-dihydroxy-8-methoxycarbonyltriptycene could be attained by means of bis-camphanate derivative. The absolute configuration of (+)-2,5-dimethoxy-8-methoxycarbonyltriptycene derived from (+)-2,5-dihydroxy-8-methoxycarbonyltriptycene was determined as 1R,6S by chemical correlation with (+)-2,5-dimethoxy-7-dimethylaminotriptycene hydrobromide whose absolute configuration had been proved to be 1R,6S by the X-ray structure analysis using the Bijvoet method.
Studies on Nitro Sugars. III. The Synthesis of 3-Nitrohexofuranose Derivatives
Authors: Takamoto Tetsuyoshi , Yokota Yoh-ichi , Sudoh Rokuro , Nakagawa Toshio 
Published: July 2006

Abstract
The oxidation of l,2;5,6-di-O-isopropylidene-3-oximino-α-d-ribo-hexofuranose (1) with trifluoroperacetic acid at a low temperature afforded, in a 75% yield, the corresponding 3-nitro-allofuranose (3), but at a high temperature it gave at least three nitro compounds, i.e., 3, 3-deoxy-1,2-O-isopropylidene-3-nitro-α-d-allofuranose (6) and 3,6-anhydro-3-nitro-α-d-glucofuranose (8). 6 was converted to 5,6-di-O-acetate (7) and confirmed by comparison with the 3-epimer (11), which was prepared by the acetonation of 3-deoxy-3-nitro-d-glucose, partial hydrolysis and acetylation. The structure of 8 was instrumentally determined and supported by the fragmentation pathways in its mass spectrometry. The formation of 8 was assumed to proceed through nitronic acid (5) as an intermediate.
The Acid-catalyzed Isomerization of α-Ylangene and α-Ylangene Epoxide
Authors: Ohta Yoshimoto , Hirose Yoshio 
Published: July 2006

Abstract
Upon treatment with dilute mineral acid, α-ylangene afforded two alcohols with amorphane carbon skeletons, 10β-hydroxyamorpha-4-ene (16) and 10α-hydroxyamorpha-4-ene (17). The carbonic acid-induced isomerization of α-ylangene epoxide yielded 3α-hydroxy-α-amorphene (19), 3α-hydroxy-δ-amorphene (20), and 3α, 10α-dihydroxyamorpha-4-ene (21). The structures of these compounds were strictly determined, and the revised structure 16 of δ-cadinol proposed by Lin was shown to conflict with the results of the isomerization of α-ylangene and with the previously-reported conversion of α-copaene into δ-cadinol (10) and T-muurolol (11) under similar conditions.
Circular Dichroism Studies of Ring-conf ormational and rotational Equilibria in 2-Isopropenylcyclohexanones
Authors: Watanabe Satoru 
Published: July 2006

Abstract
The temperature-dependent circular dichroism of optically active β,γ-unsaturated ketones, (2S, 5R)-(−)-2-isopropenyl-2,5-dimethylcyclohexanone (2) and (2S, 5R)-(−)-2-isopropenyl-5-methylcyclohexanone (3), and of the corresponding saturated ketones, (2S, 5R)-(−)-2-isopropyl-2,5-dimethylcyclohexanone (1), has been measured at the n→π* transition in order to determine the relative disposition between the carbonyl group and the ethylenic bond of the isopropenyl group of the β,γ-unsaturated ketones. The compound (2) exhibited the sign of a Cotton effect opposite to that of the corresponding saturated compound (1), and the circular dichroism of the compound (3) behaved quite differently from menthone (4). The result has been discussed mainly in terms of the geometry of the carbonyl group and the ethylenic bond of the isopropenyl group. Thus, it has been concluded that the preferred conformations of the compounds (1), (2), and (3), are 1A, 2A-III, and 3A-I respectively.
A Temperature-jump Study of the Kinetics of the Complex Formation of Iron(III) with m-Nitrophenol
Authors: Tamura Kiyoshi 
Published: July 2006

Abstract
By a new method here proposed, an expression of the relaxation time has been obtained for the formation of the monocomplex of iron (III) with a univalent anionic ligand. The method enables us to express the rate equation in a manner analogous to the second-order reaction, and to calculate the relaxation time with less mathematical labor. The validity of the treatment has been confirmed by applying it to the analysis of the complex formation reaction of iron (III) with m-nitrophenol. The kinetic measurement was performed with the temperature-jump method in an acidic aqueous solution at 25°C and at an ionic strength of 0.10. Over the acidity range studied (0.005≤[H+]≤0.026 M), the complex formation occurs significantly via one path: FeOH2++m-NO2C6H4OH\ightleftharpoonsm-NO2C6H4OFe2++H2O. The forward and backward rate constants obtained are 5.9×102 M−1s−1 and 1.8×102s−1 respectively. These results have been confirmed by examining the earlier kinetic data on similar reactions.
Excited States and Intermediates in the Photochemistry of Chromium(III) Complexes Studied by Flash Method
Authors: Ohno Takeshi , Kato Shunji 
Published: July 2006

Abstract
Photoreactions of K3[CrIII(NCS)6] and NH4[CrIII(NCS)4(NH3)2] were investigated by means of a flash technique. At low temperature (−87°C), the lowest excited doublet states (2Eg) of the complexes were easily observed on d-d excitation in acetone, the yields decreasing rapidly with rising temperature. In methanol-ethyl–eneglycol-water, 2Eg states of both complexes were easily observed at dry-ice temperature, but not at −46°C. Thus, the lowest excited quartet state (4T2g), the precursor of 2Eg state, should rapidly undergo photolysis at room temperature before being converted into the 2Eg state. The rate of thermal degradation of 4T2g state including chemical reactions was calculated to be ca. 1010 s−1 at room temperature. The decay rate of 2Eg state was estimated to be ca. 105 s−1 at room temperature. In the presence of organic compounds having carbonyl group, a strong and sharp absorption band near the UV region was observed at room temperature. Irradiation of UV light produced (NGS)2− radical for both complexes.
Initiation Step of Methane Pyrolysis. Further Studies on Initiation Step of Methane Pyrolysis
Authors: Yano Takayuki 
Published: July 2006

Abstract
The pyrolysis of diluted mixture of equimolar CH4 and CD4 were performed in a shock tube between ∼1500 K and ∼1600 K, and pyrolysis products were quantitatively determined. A small amount of oxygen contaminating the sample gases had no influence on the results. The isotope exchange reactions in the equimolar lean mixture of H2 and D2 were also performed under the same conditions of methane pyrolysis. The results explained that the isotope exchange reaction between H2 and D2 had no influence on the hydrogen isotopic distribution produced by the CH4-CD4 pyrolysis. From the hydrogen isotopic distribution of the products of CH4-CD4 pyrolysis, methyl radical mechanism was confirmed as the initiation step of methane pyrolysis.
An Investigation of a Surface Reaction between Pyrrhotite and the Hydrogen–Hydrogen Sulfide Mixture
Authors: Katsumoto Masayuki , Fueki Kazuo , Mukaibo Takashi 
Published: July 2006

Abstract
The isotopic exchange between H2S and D2 has been studied in the temperature range from 480°C to 551°C on a pyrrhotite specimen. The isotopic exchange reaction proceeded via these steps:
H2S+D2=D2S+H2
H2+D2=2HD
From the analysis of the kinetic data, the rate constant of the sulfurization of Fe1−XS by “hydrogen sulflde,” ki, and that of reduction by “hydrogen,” ki′, were determined. It was found that ki is inversely proportional to the sulfur activity of Fe1−XS, as, and that ki′ is independent of it. It was found that the rate equation for the sulfurization of Fe1−XS in the “hydrogen”-“hydrogen sulfide” gas mixture could be expressed in the form of v=kP“H2S”aS−1–k′P“H2”. A possible mechanism of the reaction at the surface of Fe1−XS is discussed.
Studies on Fragment Ion Distribution and Reactions by the Use of a Charge Spectrometer. III. Reactivities of the Excited Ions from Methylamine after Charge Exchange with Positive Ions
Authors: Nagatani Toshio , Yoshihara Kenji , Shiokawa Takanobu 
Published: July 2006

Abstract
The behavior of the excited ions produced by positive ion impact in methylamine has been studied in the reaction chamber of a double mass spectrometer at elevated pressure. The ion-molecule reactions have been discussed for three energy regions. Metastable transitions taking place in the reaction chamber and in the Giese lens have also been studied in the corresponding regions.