bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystal Structure and Absolute Configuration of (−)-2,2′-Bisbromomethyl-1,1′-binaphthyl
Authors: Harata Kazuaki , Tanaka Jiro 
Published: July 2006

Abstract
Crystals of (−)-2,2′-bisbromomethyl-l′-binaphthyl have been subjected to crystal structure analysis in order to determine the absolute configuration of optically active 1,1′-binaphthyl derivatives. The crystals are orthorhombic, space group P212121 with Z=4 and the lattice constants are; a=10.360, b=13.052, c=13.178 Å. The structure was solved by the heavy atom method and the final R index was 0.064. The absolute configuration was determined as (S)-configuration by utilizing the anomalous dispersion effect of bromine atom.
Infrared Absorption Intensities of Torsion–Rotation Transitions of Molecules with Symmetric Internal Rotor
Authors: Sugeta Hiromu , Miyazawa Tatsuo 
Published: July 2006

Abstract
The infrared absorption intensities of torsion-rotation transitions were theoretically derived on the basis of torsion-rotation interactions of molecules with symmetric internal rotor. The theoretical intensities depend upon molecular structure parameters and molecular dipole moment. Implications of the present theory are discussed on absolute intensities, orientations of dipole transition moment, band types (A, B, or C), and deuteration effects on absorption intensities of methyl torsional transitions. For propylene oxide and propylene sulfide, the far infrared spectra of the gaseous state were measured, and the experimental absorption intensities of methyl torsional vibrations were compared with theoretical intensities.
Distribution of Alkali Metal Picrates between Water and Methyl Isobutyl Ketone
Authors: Iwachido Tadashi 
Published: July 2006

Abstract
As regards the distribution of alkali metal picrates between water and methyl isobutyl ketone, distribution ratios of alkali metals and acid species were determined in the pH range 1.5–8.5. The extraction curves are almost the same for each alkali metal. Association constants of the picrates and the dissociation constant of picric acid in the organic phase were determined conductometrically. The association constants of picrates in the aqueous phase were determined with distribution coefficients by means of a solvent extraction method. The results obtained show that the picrates exist mainly in a dissociated form in both phases, whereas picric acid exists in a weakly dissociated form in the organic phase. The extractability of picrates is discussed on the basis of the extraction parameter proposed and compared with that of the nitrobenzene system.
ESR of Copper(II) Complexes in Magnetically Non-dilute Crystals. I. Single Crystals of Bis(l-alaninato)copper(II)
Authors: Yokoi Hiroshi , Ohsawa Shigeru 
Published: July 2006

Abstract
Single-crystal ESR studies have been carried out on bis(l-alaninato)copper(II). Only one symmetric absorption peak has been obtained in any direction of the magnetic field, regardless of the fact that there are two molecules per unit cell. The principal values and the directions of the principal axes of the g tensor have been determined, and a correlation between those components of the g tensor and the crystal structure has been confirmed on the basis of the effect of the spin-exchange interaction between the dissimilar copper(II) ions. The absorption linewidths have been examined in order to estimate the spin-exchange energy.
Kinetics and Mechanisms of the Reactions of Ce(IV) and Co(III) with Variamine Blue, [N-(p-Methoxyphenyl)phenylenediamine], in Aqueous Perchlorate Media
Authors: Imamura Taira , Fujimoto Masatoshi 
Published: July 2006

Abstract
The kinetics of the non-complementary reactions of Ce(IV) and Co(III) with Variamine Blue perchlorate were studied under nitrogen atmosphere in aqueous perchlorate media of ionic strength μ=2.0 M. The iminoquinone form of Variamine Blue was spectrophotometrically followed at 550 nm by stopped-flow technique. The rate constants of the stepwise reaction, Mn++(V.B.)\oversetkα\undersetkγ\ightleftharpoonsM(n−1)++(V.B.)sox,Mn++(V.B.)sox\xrightarrowkβM(n−1)++(V.B.)ox+2H+ were evaluated at 25°C to be kα=1.7×105 and kβ=2.4×105 M−1 sec−1 for Ce4+ and kα=1.35×104 and kβ=1.53×104 M−1sec−1 at [H]=1.0 M for Co3+. The rates of Ce4+ were not affected by [H]. The [H]-dependece of kα and kβ for Co3+ gives the mechanism Coaq3++B\oversetk1\ightleftharpoons product, CoOHaq2++B\oversetk2\ightleftharpoons product, Coaq3+\oversetKh\ightleftharpoonsCoOHaq2++H+, with K2\simeq107 M−1sec−1, suggesting an outer-sohere mechanism for the electron transfer with CoOH2+.
Photochemical Reactions of Uranyl Ions with Organic Compounds. V. Effects of Temperature and Solvent on the Photooxidation of Alcohols
Authors: Sakuraba Shukichi , Mimura Soichi , Matsushima Ryoka 
Published: July 2006

Abstract
A comparative study of the photokinetic behaviors of aliphatic alcohols and related substrates was made for the photooxidation with uranyl ions. Ethylene glycol, glucose, sucrose and some other substrates showed abnormal results compared to a series of simple aliphatic alcohols: the photoredox quantum yields φ for the former substrates decreased with substrate concentration (at their higher concentrations) and temperature rise, in contrast to simple aliphatic alcohols. In aqueous acetone solution φ increased with the increase in acetone content, the reaction constant ρ* being more negative than in aqueous solution. In 40% aqueous acetone solution the φ values for simple aliphatic alcohols varied in a complicated way with temperature. The abnormal results were interpreted in terms of the relative importance of physical quenching competing with the primary chemical process.
Kinetics of the Oxidation of Ascorbic Acid by the Copper (II) Ion in an Acetate Buffer Solution
Authors: Hayakawa Katumitu , Minami Shoko , Nakamura Sumio 
Published: July 2006

Abstract
The kinetics of the oxidation of ascorbic acid by the copper(II) ion has been studied spectrophotometrically by a stopped-flow technique. At pH 4–6, the initial rate of the decrease in the monohydroascorbate anion is of the second-order with respect to the total concentration of the copper(II) ion and of the first-order with respect to the concentrations of the monovalent and divalent ions of ascorbic acid:
-(d[HA^-]/dt)_t=0=k_1[Cu(II)]_T^2[HA^-]+k_2[Cu(II)]_T^2[A^2-]
where HA− and A2− are the monovalent and divalent ions of ascorbic acid respectively. k1, k2, and the activation parameters are obtained as follows: k1=3.1×104, k2=6.1×1010 M−2 s−1, ΔH\eweq=17 kcal/mol, ΔS\eweq=8.3 cal/deg mol, and ΔG\eweq=15 kcal/mol. The EPR signal from the ascorbate radical is not observed in the kinetic run by either a flow technique or a quenching technique. Some discussions of the mechanism of the reaction are given.
H+ Ion Equilibria in Solutions of Copolypeptides of l-Lysine and l-Aspartic Acid and of l-Lysine and l-Glutamic Acid
Authors: Atreyi M , Gupta R C 
Published: July 2006

Abstract
pH and conductometric titration curves of copolypeptides containing l-lysine and either l-glutamic acid or l-aspartic acid residues have provided necessary evidence to believe that in the copolypeptides the zwitterion formation is complete at the isoionic point. The amounts of acid/alkali used up at the final inflexion/break in the titration curves agreed with the analytically determined quantity of basic/acid groups in the copolypeptides. Besides, the titration curves showed additional inflexions/breaks which distinguished between the various kinds of acid/basic groups present.
The Reaction of Nitriles under High Pressure. II. The Catalytic Effects of Amines and Water on the Formation of Trisubstituted 1,3,5-Triazines from Nitriles
Authors: Yasumoto Masahiko , Yanagiya Koshin , Kurabayashi Masahiro 
Published: July 2006

Abstract
When a mixture of benzonitrile and methanol is kept under a high pressure of a few thousand atoms at an elevated temperature, methyl benziminoether is produced and trimerized to triphenyl-1,3,5-triazine. In the present study it was confirmed that the addition of ammonium salts or some nucleophiles with an active hydrogen atom such as water, amines, and ammonia at several per cents in the molar fraction increases the rate of the formation of this triazine by several times. It was found that the nucleophilic benzamidines produced by the reaction of benziminoether with amines attacked the second molecule of the iminoether and successively took the third iminoether molecule to form a triazine ring. The addition of water to the nitrile-methanol mixture produced amidine, methyl ester, amide, and amidinium carboxylate, of which the carboxylate exhibited the highest promotive effect. Some benzamidines were obtained in fairly good yields from amines and benzonitrile under similar high-pressure conditions. It is thought that this could be useful for synthesizing amidines.
The Reaction of Nitriles under High Pressure. IV. The Replacement of the Substituents of Trialkyl-1,3,5-triazines
Authors: Yanagiya Koshin , Yasumoto Masahiko , Kurabayashi Masahiro 
Published: July 2006

Abstract
It was found that, when some symmetrically 2,4,6-tri-substituted 1,3,5-triazines are kept with an iminoether or an amidine under high pressures and at elevated temperatures, unsymmetrically 2,4,6-tri-substituted 1,3,5-triazines are produced by way of the replacement of one or two (Remark: Graphics omitted.) groups of the triazines with the (Remark: Graphics omitted.) group of the iminoether or that of the amidine. Several mixtures of nitriles and methanol can be used for this replacement reaction in place of iminoethers or amidines at 4000–8000 atm and 100–150 °C. In these mixtures, equilibrium amounts of methyl iminoethers are rapidly formed. Increases in the size of the substituents of the original triazine and in their electron-releasing power inhibit this replacement reaction. Nitriles with an electron-releasing moiety give tri-substituted triazines replaced selectively by one of the original substituents.
Linear Conjugated Systems Bearing Aromatic Terminal Groups. XII. Syntheses and Electronic Spectra of α,ω-Di-2-pyrenyl-and α,ω-Di-2-fluorenylpolyenes
Authors: Takeuchi Yasuhira , Yasuhara Akio , Akiyama Shuzo , Nakagawa Masazumi 
Published: July 2006

Abstract
The syntheses of α,ω-di-2-pyrenyl- and α,ω-di-2-fluorenylpolyenes In and In′ (n=1–6) by means of the Wittig reaction are described. Aldehydes II, II′, propenals IV, IV′, pentadienals V, V′ bearing 2-pyrenyl or 2-fluorenyl terminal group and muconaldehyde VI were used as carbonyl components. Phosphoranes III, III′, VII, VII′, VIII and VIII′ were prepared from methyl-, propenyl-, and pentadienyltriphenylphosphonium bromides substituted with 2-pyrenyl or 2-fluorenyl group by the reaction with phenyllithium. In and In′ were obtained by the reaction of carbonyl components with phosphoranes by proper combination. It was found that the bathochromic shift of the longest-wavelength peaks of In and In′ can be expressed by the following empirical equations:
& I_n:λ=44.6n^0.7+314 (nm in tetrahydrofuran)
& I_n’:λ=29.5n^0.8+353 (nm in tetrahyhrofuran)
Linear Conjugated Systems Bearing Aromatic Terminal Groups. XIII. Syntheses of α-(p-Methoxypheny)-ω-(p-nitrophenyl)polyenes
Authors: Takeuchi Yasuhira , Akiyama Shuzo , Nakagawa Masazumi 
Published: July 2006

Abstract
α-p-Methoxyphenyl-ω-p-nitrophenylpolyenes (IIIn, n=1–5) were prepared by the Wittig reaction of p-methoxyphenylpolyenals (I, n=1–5) with phosphorane derived from p-nitrobenzyltriphenylphosphonium bromide (II). The electronic spectra of IIIn showed broad and structureless absorption curves. However, the trend of bathochromic shift of long wavelength absorption maxima with increasing length of polyene chain suggests that no alternation in the type of light-absorption of polyene chromophore is caused by the introduction of electron donating and withdrawing substituents in the terminal phenyl groups.
A New Hypothesis Regarding the Surface Acidity of Binary Metal Oxides
Authors: Tanabe Kozo , Sumiyoshi Takashi , Shibata Katsue , Kiyoura Tadamitsu , Kitagawa Jun 
Published: July 2006

Abstract
We have proposed a new hypothesis that the acid sites on binary metal oxides are formed by an excess of a negative or positive charge in the mixed oxides and that whether the charge is excess or not, and whether it is positive or negative, are determined by the coordination numbers and valences of the positive and negative elements in the model structures pictured according to two postulates. The validity of the hypothesis is, in fact, 90% for the 31 kinds of binary oxides tested, much higher than the validity (48%) of Thomas’ hypothesis. The hypothesis explains well the mechanism of the acidity generation of binary oxides and predicts whether the acid sites will be of the Brönsted or the Lewis type.
The Raman Spectra and Molecular Conformations of Surfactants in Aqueous Solution and Crystalline States
Authors: Okabayashi Hirofumi , Okuyama Masataka , Kitagawa Teizo , Miyazawa Tatsuo 
Published: July 2006

Abstract
The Raman spectra were measured for sodium alkyl sulfates and potassium aliphatic carboxylates in the solid state and aqueous solutions. Vibrational assignments of Raman lines were made, and characteristic Raman lines of the alkyl sulfate ion were identified. The ethyl sulfate ion in the aqueous solution was found to exist predominantly as the trans form about the CH2–O bond. For higher alkyl sulfate ions in aqueous solutions, Raman lines due to rotational isomers with gauche CH2–CH2 bonds were observed. Longitudinal accordion frequencies of the solid state and aqueous solutions were compared in order to discuss the conformations of hydrocarbon chains in solution.
Electrical Properties of Ferric Oxyhydroxides
Authors: Kaneko Katsumi , Inouye Katsuya 
Published: July 2006

Abstract
The electrical conductivity of α-FeOOH, β-FeOOH, and γ-FeOOH was measured in dry air at room temperature in the frequency range of dc to 10 MHz under various pressures of 9–150 kg/cm2. The logarithm of conductivity, log σ, shows a linear relationship with the ratio of true density to apparent density, d0/d′, of the samples compressed at different pressures. σ1 at 7 MHz, determined by extrapolating the logσ vs. d0/d′ plots to unity of d0/d′, is proportional to the number of the nearest iron atoms with identical spin. The conductivity increases with increasing frequency f. The ac conductivity σac which equals σ minus σdc, where σdc is the dc conductivity, is proportional to fs (0.6&lt;s&lt;0.8) in the lower frequencies than 1 MHz. This behavior is presumed to be due to the hopping of a d-electron in the t2g-orbital of Fe2+ to the t2g-orbital of adjacent Fe3+, through a slight overlapping of t2g-orbitals of Fe2+ and Fe3+.
Brillouin Scattering and Elastic Constants of Tetragonal Pentaerythritol
Authors: Matsuura Hiroatsu , Miyazawa Tatsuo 
Published: July 2006

Abstract
The Brillouin scattering from tetragonal pentaerythritol crystals was measured by using a helium–neon laser and a pressure-scanned Fabry-Perot interferometer. The Brillouin components from the longitudinal acoustic mode and the transverse acoustic mode polarized parallel to the scattering plane were observed for various crystal directions with the scattering vector in the (001) and (010) planes. From the observed Brillouin shifts, the frequencies and velocities of sound waves with the wavelength of 290 nm were obtained, and the elastic constants were determined, in units of 1011 dyn/cm2, as C11=3.94±0.01, C13=0.76±0.03, C16=0.005±0.05, C33=1.33±0.02, C44=0.44±0.03, and 2C66+C12=5.13±0.03. The present hypersonic values of the elastic constants were compared with previous values by the ultrasonic technique.
Synergism in the Liquid-Liquid Extraction and the Extractio Chromatography of Manganese(II), Cobalt(II), and Zinc(II) in the Thenoyltrifluoroacetone–Trioctylphosphine Oxide–Cyclohexane Extraction System
Authors: Honjo Takaharu , Horiuchi Masanobu , Kiba Toshiyasu 
Published: July 2006

Abstract
The synergism appearing in the liquid-liquid extraction and the extraction chromatography of trace amounts of manganese(II), cobalt(II), and zinc(II) has been investigated with TTA (thenoyltrifluoroacetone) in various solvents with or without TOPO (tri-n-octylphosphine oxide). For example, the pH1⁄2 of the extraction of Co(TTA)2 differed with the solvent used; it was, for example, 4.1 for nitrobenzene, 4.6 for cyclohexane, and 5.2 for benzene, when examined with 0.1 M TTA. When 0.01 M TOPO was present under the same conditions, the above values became 3.3, 2.4, and 3.1 respectively. The synergism was thus found to become more effective as a less polar solvent was used. The extraction constants of the three metals with only 0.1 M TTA–cyclohexane increases in the order of Mn(II)–Zn(II)–Co(II); however, when 0.001 or 0.01 M TOPO was present, all the extraction curves of the three metals became identical, even in the acidic region of pH 1–4. The overall stability constants of the adducts, M(TTA)2–(TOPO)n, increased in the order of Zn(II)–Co(II)–Mn(II), unlike the case of M(TTA)2. The adducts were found to have two TOPO for Mn(II) and Co(II), but only one for Zn(II). The extraction equilibria were found to be attained within two minutes. Unlike as in the batch extraction, the columnextraction chromatography gave a dissimilar order of the extractability of three metals (Zn(II)–Mn(II)–Co(II)) when 0.1 M TTA–cyclohexane was the stationary phase on Kel–F in the presence of TOPO. The mutual separation could not be achieved among these metals in the presence of TOPO, and the synergism was found to be rather unfavorable for the separation of metals. The relation between the batch extraction and the extraction chromatography was also discussed briefly on the basis of the distribution data obtained.
Studies on Amino-hexoses. XVIII. A Simplified Method of Preparing 2-Amino-3-O-(d-1′-carboxyethyl)-2-deoxy-d-glucose 6-(Dihydrogen Phosphate) (Muramic Acid 6-Phosphate)
Authors: Hase Sumihiro , Matsushima Yoshio 
Published: July 2006

Abstract
Muramic acid 6-phosphate was prepared from benzyl 2-acetamido-2-deoxy-3-O-[d-1′(methoxycarbonyl)-ethyl]-α-d-glucopyranoside via two reaction stages: diphenylphosphorylation under restricted conditions, followed by hydrolysis. When the reaction mixture was chromatographed on a Dowex 1×8 (formate form) column, the product was obtained as fine needles. Among the periodate oxidation products of the compound, glycolaldehyde phosphate was detected, while formaldehyde was not. Equimolar amounts of muramic acid and inorganic phosphate were produced by an alkaline phosphatase. The physical data are consistent with those of authentic muramic acid 6-phosphate.
The Formation of Ethers from Borneol and Isoborneol in the Presence of Boron Trifluoride Etherate
Authors: Nagai Kimiko , Nakayama Mitsuru , Matsuo Akihiko , Eguchi Shizuko , Hayashi Shûichi 
Published: July 2006

Abstract
dl-Borneol and dl-isoborneol, when separately submitted to the action of boron trifluoride etherate at room temperature, gave different ethers; the one from borneol was characterized as bornyl isobornyl ether, and the other from isoborneol, as diisobornyl ether. The ethers were also obtained from borneol and isoborneol in the reaction with zinc chloride. When d-borneol was used, an optically-active bornyl isobornyl ether was obtained.
Synthetic Studies of Carbohydrate Derivatives with Photochemical Reactions. X. An Unusual Photo-induced Addition of Lactonitrile to Some Enoses
Authors: Matsuura Kazuo , Senna Kazuo , Araki Younosuke , Ishido Yoshiharu 
Published: July 2006

Abstract
The photochemical addition of lactonitrile to 3,4,6-tri-O-acetyl-d-glucal, 2,3,4,6-tetra-O-acetyl-2-hydroxy-d-glucal, methyl 4,6-di-O-acetyl-2,3-dideoxy-α-d-erythro-hex-2-enopyranoside, and methyl 5-deoxy-2,3-O-isorpopylidene-β-d-erythro-pent-4-enofuranoside afforded 1′-cyanoethyl 4,6-di-O-acetyl-2,3-dideoxy-α-(6a) and -β-d-erythro-hex-2-enopyranoside(6b), 1′-cyanoethyl 2,4,6-tri-O-acetyl-3-deoxy-α- and -β-d-erythro-hex-2-enopyranoside, 6a and 6b, and 1′-cyanoethyl [methyl (4R)-5-deoxy-2,3-O-isopropylidene-β-d-erythro-pentofuranosid]-4-uloside respectively, all in good yields. These facts can be explained by assuming the catalytic effect of a certain acidic species which might extricated from lactonitrile during the irradiation.
Catalytic Hydrogenation of Cyclic Olefins on Nickel Catalysts
Authors: Kajitani Masatsugu , Sasaki Yoshiaki , Okada Junko , Ohmura Kazuo , Sugimori Akira , Urushibara Yoshiyuki 
Published: July 2006

Abstract
The catalytic hydrogenation of cyclic olefins was investigated over various nickel catalysts. The hydrogenation of cyclohexene was promoted by basic reaction conditions and depressed by acidic ones, the hydrogenation of cyclooctene being only slightly influenced by the acidity. The results of competitive hydrogenation indicate that cyclooctene is adsorbed more strongly on nickel catalysts than cyclohexene. The external olefinic bond is preferentially hydrogenated to the internal olefinic bond.
Oxytocin Analogues Containing No Disulfide Bond. III. The Synthesis of Three Analogues of 1,6-Aminosuberic Acid-Oxytocin
Authors: Yamanaka Tsutomu , Sakakibara Shumpei 
Published: July 2006

Abstract
[Asu1,6]-oxytocin, an analogue of deamino-oxytocin in which the disulfide bond is replaced by an ethylene linkage, is completely resistant to deterioration during storage under concentrated conditions. In the present study, three new analogues of this material, [Phe3, Asu1,6]-oxytocin, [Val4, Asu1,6]-oxytocin, and [Gly7, Asu1,6] -oxytocin, were synthesized to find out a hormonal compound possessing a specifically higher uterotonic activity. Among them, the [Gly7]-analogue was found to be the most promising compound; it showed a relatively higher uterotonic activity (245 IU/mg) in the rat, with a faint antidiuretic activity (0.02 IU/mg) and a weak depressor activity.
Substituent Effects in the Benzofuran System. I. Proton and Carbon-13 Chemical Shifts
Authors: Okuyama Tadashi , Fueno Takayuki 
Published: July 2006

Abstract
PMR and CMR spectra of benzofuran and its derivatives (2-CH3, 3-CH3, 5-CH3, 6-CH3, 5-CH3O, 6-CH3O, and 5-Cl) have been measured. The chemical shifts of 2-H and 2-C of 5- and 6-substituted derivatives obeyed a modified Hammett equation, δ=ρ1σ1+ρ2σ2+δ0. Electronic effects were found to be transmitted mainly through the bond 8–3. It was concluded that the ground-state electronic structure is similar to that of styrene rather than phenyl vinyl ether.
Molecular Structure of Tungsten Oxide Tetrachloride by Gas Electron Diffraction
Authors: Iijima Kinya , Shibata Shuzo 
Published: July 2006

Abstract
The molecular structure of tungsten oxide tetrachloride was determined by the sector-microphotometer method of gas electron diffraction. The molecule was found to have a square-pyramidal structure, and the following molecular parameters were obtained by a least-squares method; rg(W–Cl)=2.281±0.003 Å, rg(W–O)=1.686±0.011 Å, and rg(Cl···Cl(s))=3.151±0.015 Å. The OWCl angle, 102.4±1.3°, is much larger than the corresponding angles found in other square-pyramidal molecules such as XeOF4 and IF5.
Isoelectric Point of Manganese Oxide
Authors: Morimoto Tetsuo , Kittaka Shigeharu 
Published: July 2006

Abstract
The isoelectric point (IEP) of manganese oxide is measured on samples prepared by heating β-MnO2 and amorphous manganese oxide, MnO1.75, at temperatures from 200 to 1400°C. The IEP values thus obtained are characteristic of each stage of the oxidation of manganese oxide; that is, &lt;5.1 for MnO2, 7.6–9.0 for α-Mn2O3, and 3.3–5.2 for Mn3O4. These values can be explained by the electrostatic interaction theory introduced by Parks, in which the CFSE correction is eliminated. It is also found that manganese ions with specific valencies are responsible for the electrification of the surfaces of manganese oxide.