bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of Liquid-phase Hydrogenation of Aliphatic α,β-Unsaturated Aldehyde over Raney Cobalt Catalyst Modified with Co-, Mn-, Ni-, and PdCl2
Authors: Hotta Kazuhiko , Kubomatsu Teruo 
Published: July 2006

Abstract
Kinetic studies were carried out on the hydrogenation of the α,β-unsaturated aldehyde, 2-methyl-2-pentenal (UD), over the Raney cobalt catalyst modified with various amounts of Co-, Mn-, Ni- and PdCl2 in n-hexane under atmospheric pressure at 40 and 20°C. Initial rates of formation of the saturated aldehyde (rSD), saturated alcohol(rSA) and unsaturated alcohol(rUA) were determined in the concentration range of UD((CUD) 0.018–0.263 mol/l. It was found that (rSD+rSA) obeyed a Langmuir-type rate equation and rUA a different one. The rate equations are as follows.
r SD+rSA=\frack1·b1·CUD(1+b1·CUD)2, rUA=\frack2·b2·CUD(1+b2·CUD)2
where k and b denote the rate constant of the surface reaction and parameter for the adsorption of UD and hydrogen, respectively, the subscripts 1 and 2 representing the formation of SA and SD and that of UA, respectively. Kinetic parameters k1, k2, b1 and b2 were found to vary with the amount and kind of modifier. The variation of b1 and b2 was irregular. The rate constant k1 decreased with increasing amount of Co-, Mn- and NiCl2 added; it increased remarkably with the addition of PdCl2. The variation of k2 was more complicated. Addition of a small amount of the modifiers did not decrease k2. Further addition of Co- and MnCl2 made k2 decrease, while that of NiCl2 made it increase. Mechanism of the modification with these metal chlorides is discussed on the basis of the active site hypothesis.
The Kinetic Study on the Reaction of Oxaziridine with Tri-n-Butylphosphine
Authors: Tamagaki Seizo , Sakaki Keishi , Oae Shigeru 
Published: July 2006

Abstract
The mechanism of deoxygenation reaction of oxaziridine with trivalent phosphine was kinetically examined by changing substituents, solvents, and temperatures. The reaction proceeds through an attack of phosphine on oxgen in a concerted manner rather than on nitrogen or carbon, eventually producing the corresponding imine and phosphine oxide. The mechanism of the title reaction was compared with those of similar deoxygenations of epoxide and thioepoxide.
Ultrasonic Study on Dilute Aqueous Solutions of Diamines
Authors: Sasaki Katsutaka , Arakawa Kiyoshi 
Published: July 2006

Abstract
Ultrasonic experiments were carried out on aqueous solutions of diamines (ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexanediamine) by means of pulse technique in order to study solute-solvent interactions. Sound velocity and absorption coefficient were determined in the frequency range 15–45 MHz. The magnitude of absorption coefficient for each solution increased rapidly with concentration up to about 0.4 mol%. It is concluded that the initial rapid increase is attributed to the proton transfer in base equilibria. The absorption coefficient at the same molar concentration of each solution increases appreciably with the size of hydrocarbon chain from –(CH2)2– to –(CH2)3–. This is ascribed to the formation of icebergs around hydrocarbon groups.
The Effect of Pressure on the Sol-Gel Transformations of Macromolecules
Authors: Suzuki Keizo , Taniguchi Yoshihiro , Enomoto Toshishige 
Published: July 2006

Abstract
The effect of pressure on the gelation of macromolecules, such as gelatin, polyvinyl alcohol, and methyl cellulose, was investigated in order to clarify which binding forces contribute to their gel formations. The values for ΔH and ΔV accompanying the gel formation were calculated from the Eldrige-Ferry’s plot and the Clausius-Clapeyron equation respectively. The values for ΔH and ΔV in the gel fromations of gelatin and polyvinyl alcohol are both negative, while those in methyl cellulose are both positive. From the thermodynamical considerations, it has been found that the formation of hydrogen bonds results in negative values of ΔV Fand ΔH, while that of hydrophobic bonds results in positive values of ΔV and ΔH. Therefore, it may be assumed that the main binding forces in the gelations of gelatin and polyvinyl alcohol may be attributed to hydrogen bonds, and that those in methyl cellulose may be attributed to hydrophobic bonds, at least up to 6000 atm.
Electron Spin Resonance Studies of the Carbon Dioxide Anion Radical Adsorbed on X-Type Zeolites
Authors: Sogabe Kunihisa , Hasegawa Akinori , Yamada Yoshio , Miura Masaji 
Published: July 2006

Abstract
The hindered motion and the structure of the CO2− radical adsorbed on various zeolites were investigated by means of ESR spectroscopy. The adsorbed CO2− radical was obtained by the γ-irradiation of zeolites with carbon dioxide labeled with 13C. The results show that the interaction of the CO2− radical with the zeolite surface changes with the electrostatic field on the surface. The motion and the structure of the adsorbed CO2− radical are affected by the properties of the zeolite surfaces; the former is also influenced by the extent of exchange of the cation on zeolite, regardless of the time of irradiation, before or after the introduction of carbon dioxide. The formation of the CO2− radical on zeolites was interpreted on the basis of such a mechanism that electrons are initially trapped by the surface of zeolite upon the irradiation and then transferred to carbon dioxide molecules. The results also show that the process of the electron transfer depends on the kind of cation.
The Stereochemistry and the Circular Dichroism of Several Pinane Derivatives
Authors: Hirata Toshifumi 
Published: July 2006

Abstract
The optical rotatory dispersion and the circular dichroism curves were measured for some bicyclo[3.1.1]heptane derivatives. The applicability of the octant rule to a bicyclo[3.1.1]heptane system was discussed in connection with its preferred conformation; the conformation was determined on the basis of nuclear magnetic resonance spectrum measurements.
A Deuteron Magnetic Resonance Study of the Motion of Ligands in [Co(ND3)5(D2O)](ClO4)3
Authors: Ito Takeshi 
Published: July 2006

Abstract
The deuteron magnetic resonance of single crystals of aquopentamminecobalt(III) perchlorate was measured at various temperatures. The observed quadrupole coupling shows that [Co(ND3)5(D2O)]3+ ions execute a rapid isotropic reorientation at high temperatures (above 320°K), while only a C3 axis reorientation of the ligand ND3groups is present at low temperatures (below 290°K). No anisotropic uniaxial reorientation was observed about the C4 axis parallel to the Co–(D2O) direction. At temperatures between 310°K and 320°K, the spectrum of a fast exchange limit was observed, together with the spectrum of a slow exchange limit. This anomaly may be explained by the classical rotation of the D2O ligand.
Characterization of the Geometrical Isomers of the Carbonato(or oxalato)-aminoacidatodiammine Complexes of Cobalt(III)
Authors: Nakai Kiyoshi , Kanazawa Shuji , Shibata Muraji 
Published: July 2006

Abstract
Three geometrical isomers of the [CoCO3(aa)(NH3)2]-type complex (aa stands for the α-alaninate, β-alaninate or valinate ion)—the mer(cis-diammine)-, mer(trans-diammine)- and fac-isomers—have been prepared. Three similar isomers of the [Co ox(gly)(NH3)2] and [Go ox(β-ala)(NH3)2] complexes have been obtained by reactions of the corresponding carbonato complexes with an oxalate. In addition, the corresponding three isomers of a related [Co(gly)(NH3)2(OH2)2]2+ complex have been prepared. The isomers thus obtained have been characterized by their absorption, PMR, and IR spectra. Of the mer(trans) isomers of the present complexes, those of the carbonato-α-alaninato and carbonatovalinato complexes revealed clear shoulders in their second absorption bands. Through the present study, some relationships between the appearance of such a shoulder in the mer(trans-diammine) isomer and the ring size of chelates have been deduced.
Determination of the Stability Constants of the Bis(selenocyanato)mercury(II) and Tris(selenocyanato)mercurate(II) Complexes by a Polarographic Method
Authors: Murayama Teisuke , Takayanagi Akio 
Published: July 2006

Abstract
Selenocyanate ions give an anodic polarographic wave with a half-wave potential of 0.033 V (vs. SCE) at 25°C and 0.044 V at 35°C for a 1 mM solution. The electrode process is: Hg\ightleftharpoonsHg2++2e, Hg2++2SeCN-\ightleftharpoonsHg(SeCN)2, Hg2++3SeCN−\ightleftharpoonsHg(SeCN)3−. By means of an equation which gives the relation between the anodic current and electrode potential, stability constants of the bis(selenocyanato)mercury(II) and tris(selenocyanato)-mercurate(II) complexes (β2 and β3, respectively) were calculated from the polarograms. Values of logβ2 and logβ3 at ionic strength 0.3 are, respectively, 21.43 and 25.66 at 25°C, and 20.44 and 24.48 at 35°C.
The Thermal Reaction of 3-Benzoylguaiazulene and Methyl Guaiazulene-3-carboxylate
Authors: Kurokawa Shinji , Hashimoto Mamoru , Hayashi Shûichi 
Published: July 2006

Abstract
3-Benzoylguaiazulene (I) and methyl guaiazulene-3-carboxylate (XI) were heated at 250–260°C. From 3-benzoylguaiazulene we obtained, besides S-guaiazulene (II), three new azulenoids, which were established to be 2-benzoylguaiazulene (III), 1-benzoyl-7-isopropyl-3,4-dimethylazulene (IVa) and 2-benzylguaiazulene (V). On the other hand, the products yielded from methyl guaiazulene-3-carboxylate, together with S-guaiazulene, were elucidated to be methyl 7-isopropyl-3,4-dimethylazulene-1-carboxylate (XII) and methyl guaiazulene-2-carboxylate (XIII). In addition to the loss and the migration of the acyl group, the exchange of acyl and methyl groups in the five-membered ring took place in both acylguaiazulenes, as well as in the case of 3-acetylguaiazulene reported earlier. Moreover, the reduction of the acyl group was also observed in 3-benzoylguaiazulene.
The Synthesis of 3′-Phosphate and 2′,3′-Cyclic Phosphate of 2-Amino-4-hydroxy-6-(1′,2′,3′-trihydroxypropyl)pteridine
Authors: Sugiura Katsura , Yamashita Haruhiro , Goto Miki 
Published: July 2006

Abstract
2-Amino-4-hydroxy-6-(d-erythro-1′,2′,3′-trihydroxypropyl)pteridine 3′-phosphate and 2′,3′-cyclic phosphate, important intermediates of pteridine biosynthesis, were prepared by simple methods. d-erythro-, l-erythro-, d-threo-, and l-threo-isomers of 2-amino-4-hydroxy-6-(1,′,2,′3′-trihydroxypropyl)pteridine, prepared by the method of Viscontini, were phosphorylated with a mixture of phosphorus pentoxide and phosphoric acid. The products were separated by chromatography on a DEAE-cellulose column. The main phosphorylated compounds were 3′-phosphates; small amounts of 2′,3′-diphosphates were also produced. On treatment with DCC, the 3′-phosphate gave 2′,3′-cyclic phosphate.
Crystal and Molecular Structure of ω-Amino Acids, ω-Aminosulfonic Acids and Their Derivatives. I. The Crystal and Molecular Structure of γ-Guanidinobutyric Acid Hydrochloride and Hydrobromide
Authors: Maeda Tomie , Fujiwara Takaji , Tomita Ken-ichi 
Published: July 2006

Abstract
The crystals of γ-guanidinobutyric acid (GGBA) hydrochloride and hydrobromide, C5H12O2N3Cl and C5H12O2N3Br, are both triclinic, space group P\bar1, with two molecules in a unit cell with the following dimensions; hydrochloride: a=7.41, b=9.12, c=7.25 Å, α=101.5°, β=112.4°, γ=65.2°; hydrobromide: a=7.94, b=9.36, c=7.78 Å, α=103.2°, β=115.5°, γ=61.5°. The X-ray structure analysis was carried out by the application of heavy atom method and refined by three dimensional least-squares method. Since GGBA hydrochloride and hydrobromide are isomorphous, the structure analysis was started by using of X-ray data of the hydrobromide to determine the rough atomic coordinates of its molecule, and the data of hydrochloride were used for the further refinement. The positions of the involved twelve hydrogen atoms were located by a three dimensional difference Fourier analysis. GGBA cation, +NH2(NH2)CNH(CH2)3COOH, and Cl− ion were almost perfectly on the (20\bar1) plane and formed a pararell sheet structure with six hydrogen bonds. The possible resonance structures were also discussed.
Reaction of Organoaluminum Coordination Compound with Carbon Dioxide
Authors: Inoue Shohei , Yokoo Yoshiharu 
Published: July 2006

Abstract
The reaction of trialkylaluminum with carbon dioxide was suppressed by the presence of N,N,N′,N′-tetramethylethylenediamine, 2,2′-dipyridyl, N-methylimidazole (MIm), and diethyl ether. On the other hand, the insertion reaction of carbon dioxide into the Al–N bond of diethylaluminum diethylamide was accelerated by the presence of MIm, N-methylbenzimidazole, and pyridine. The complexing agents are considered to play two different roles, i. e., affecting the nucleophilicity of Al–C or Al–N bond and the ability of aluminum atom to accomodate carbon dioxide.
Studies of Organosulfur Compounds. VI. The Preparation of Carbamoyl Esters of Aromatic Dithio Acids and Their Spectral Properties
Authors: Kato Shinzi , Mitani Tsuyoshi , Mizuta Masateru 
Published: July 2006

Abstract
It was found that aromatic dithio acids readily reacted with aryl isocyanate at room temperature to give the corresponding mixed thioanhydrides with the general formula of (ArCS·S·CONHAr) in excellent yields as stable crystals. The mixed thioanhydrides reacted with primary amines at room temperature to give the corresponding thioamides and asymmetric ureas, while the reaction with secondary amines gave the corresponging amine salts and asymmetric ureas in good yields. The spectral properties of the mixed thioanhydrides were discussed.
Asymmetric Hydrogenation of the C=N Bond. A Study of the Controlling Factors on the Stereoselectivity
Authors: Yoshida Takao , Harada Kaoru 
Published: July 2006

Abstract
Asymmetric catalytic hydrogenation of Schiff bases, i. e., N-(methylbenzylidene)-α-methylbenzylamine and N-(ethylbenzylidene)-α-ethylbenzylamine, using 10% palladium hydroxide on charcoal was studied to elucidate the steric course of the reaction. Effects of temperature, solvent, pressure, the amount of the catalyst, and ratio of the syn and anti isomers on the asymmetric hydrogenation were investigated. Temperature, solvent, the amount of the catalyst were found to be factors which controlled the stereoselectivity of the reaction. The hydrogenation of N-(methylbenzylidene)-α-methylbenzylamine always gave a higher asymmetric yield than that of N-(ethylbenzylidene)-α-ethylbenzylamine. Lowering the reaction temperature, lowering the polarity of the solvent, and decreasing the amount of the catalyst gave higher stereoselectivities in the hydrogenation reactions.
Abnormal Hyperfine Splitting in the ESR Spectra of α,α,γ,γ-Tetraphenylallyl-type Organic Stable Free Radicals
Authors: Watanabe Kohji , Yamauchi Jun , Ohya-Nishiguchi Hiroaki , Deguchi Yasuo , Takaki Hideo 
Published: July 2006

Abstract
The ESR spectra of α,α,γ,γ-tetraphenylallyl radical have been first observed. An abnormal ESR hyperfine splitting of this radical has been compared with the ESR hyperfine splitting of other tetraphenylallyl-type radicals; it can be explained very well by introducing the idea of a twisted-allyl model of the molecule.
Monolayers of Poly-γ-benzyl-l-glutamate N-Alkylamides
Authors: Suzuki Asahi 
Published: July 2006

Abstract
To elucidate the effect of long alkyl chains on the surface properties of polypeptides, various poly-γ-benzyl-l-glutamate (PBLG) hexylamides or dodecylamides with different degrees of polymerization were synthesized and their monolayers were examined. PBLG-alkylamides with a low degree of polymerization form expanded type monolayers on water and their surface pressure-area (π-A) curves have two plateaus. The lower plateau in the π-A curve is not seen in the curves of PBLG-alkylamides with a degree of polymerization of more than 10. The lower plateau in the π-A curve is due to the behavior of the terminal alkyl groups. The effect of temperature on the properties of monolayers was examined. Structures formed in the monolayers were discussed.
Syntheses of Some Medium Sized Cyclic Triamines and Their Cobalt(III) Complexes
Authors: Koyama Hiroyuki , Yoshino Tamotsu 
Published: July 2006

Abstract
Four cyclic triamines of a medium ring size (9–12-membered ring) which form three mutually-adjacent five- and/or six-membered chelate rings on complexation, such as 1,4,7-triazacyclononane (abbreviated TACN), 1,4,7-triazacyclodecane (TACD), 1,4,8-triazacycloundecane (TACUD), and 1,5,9-triazacyclododecane (TACDD) were synthesized and isolated as their trihydrobromides. The complexation of TACN and TACD with a cobalt-(III) salt yielded metal complexes of a sandwich-type structure, such as [Co(TACN)2]Br3 and [Co(TACD)2]Br3·H2O, which were then isolated. In the case of TACUD, a complex [Co(TACUD)BrCl2] containing only one molecule of the triamine was isolated. However, although the formation of a cobalt (III) complex with TACDD in solution was inferred spectroscopically, no expected complex was isolable. On the basis of the spectrophotometric data, the ligand-field strength was found to increase in the following order:
[Co(NH3)6]3+&lt;[Co(TACD)2]3+&lt;[Co en3]3+&lt;[Co(TACN)2]3+.
The Rearrangement of 2α-Hydroxy-10β-pinan-3-one with Acetic Anhydride
Authors: Hirata Toshifumi 
Published: July 2006

Abstract
The reaction of (+)-2α-hydroxy-10β-pinan-3-one (1) with acetic anhydride afforded (+)-2α-acetoxy-10β-pinan-3-one (2), (−)-carvone (3), (−)-4α-acetoxy-10α-pinan-3-one (4), (+)-4β-acetoxy-10β-pinan-3-one (5), and (−)-4β-acetoxy-10α-pinan-3-one (6). The three products, 4, 5, and 6, were newly identified on the basis of a combination of chemical and physico-chemical methods. By examination using the 14C-labelled acetate (2), the formation of 4, 5, and 6 was shown to arise from the intramolecular rearrangement of 2. The mechanistic implications of the reaction are given.
Electron Spin Resonance Studies of Bis(acetylacetonato)copper(II) Adsorbed on X-Type Zeolite. I. Interaction with Ammonia and Aniline
Authors: Yamada Yoshio 
Published: July 2006

Abstract
The interaction of bis(acetylacetonato)copper(II) (Cu(acac)2) adsorbed on X-type zeolite of the sodium form and on silica gel with ammonia and aniline was investigated by ESR. The magnetic and bonding parameters for Cu(acac)2 on the surfaces indicate that the axial-ligand field about the copper on the surfaces is similar to that in a toluene solution. This finding implies that the copper in Cu(acac)2 does not interact strongly with these surfaces. However, it was deduced from the change in the spectrum at higher temperatures that the quasi-π-electrons in Cu(acac)2 interact with the electrostatic field arising from the cations on the zeolite. When ammonia or aniline was introduced, the bonding characters of the complex altered significantly. It was found, from the variation in the parameters, that the axial-ligand field about the complex strengthens and that an adduct is formed. Furthermore, a spectral line at g=2.004, which was observed only for Cu(acac)2 on the zeolite in the presence of aniline, was considered to be due to a cation radical formed by an electron transfer from the aniline to the complex.
Metal Catalysts Supported on Zeolite. II. Dehydrogenation of Cyclohexane and Hydrodemethylation of Toluene over Zeolite-Supported Platinum Catalysts
Authors: Kubo Toshihiko , Arai Hiromichi , Tominaga Hiroo , Kunugi Taiseki 
Published: July 2006

Abstract
Correlations between the amount of hydrogen adsorption and the catalytic activities of the zeolite-supported platinum catalysts were interpreted in terms of the dispersion state of platinum particles. The activities for dehydrogenation of cyclohexane and hydrodemethylation of toluene were directly proprotional to the amount of hydrogen adsorption. The tiny platinum particles with diameters of less than 20 Å, which had little ability to chemisorb hydrogen, showed a poor activity in both reactions.
The Heat of Adsorption from Solution. I. The Heat of Adsorption of Benzene on Silica Gel from the Benzene-Cyclohexane Solution
Authors: Morimoto Tetsuo , Naono Hiromitu 
Published: July 2006

Abstract
The sensitivity and reliability of the improved-flow micro-calorimeter have been examined by supplying given amounts of electric energy to the calibration heater inserted in the calorimeter. The detection limit of the heat amount was found to be 0.01 meal, and its probable error to be ±0.5 and ±0.3% at the heat evolutions of 10 and 40 meal respectively. The heat of the adsorption of benzene on silica gel from a cyclohexane solution has been measured at 30°C by the calorimeter thus constructed. The adsorption calorimetry indicates that benzene is adsorbed reversibly on silica gel, and that the differential heat of the adsorption of benzene is independent of the amount of adsorbed benzene, but that it depends strongly on the pretreatment temperature of the silica gel. The heats of adsorption were found to be 1.2, 1.6, 2.0, and 3.8 kcal/mol on silica gel samples treated at 100, 300, 500, and 800°C respectively. The findings on the heats of adsorption have been elucidated in terms of the interaction between benzene molecules and silanol groups on silica gel.
Isolation of the Intermediate in the Tricyanovinylation of Indole and N-Methylindole
Authors: Shirota Yasuhiko , Ezaki Sadayuki , Kusabayashi Shigekazu , Mikawa Hiroshi 
Published: July 2006

Abstract
The intermediate has been isolated in the tricyanovinylation of indole and N-methylindole. The neutral adduct structure at the 3-position is assigned on the basis of spectroscopic as well as chemical evidence. The mechanism for tricyanovinylation is discussed.
Excitation Transfer in the Radiolysis of Solid Alkane Mixtures at 77 K
Authors: Miyazaki Tetsuo , Wakayama Terunobu , Fukaya Mitsuharu , Saitake Yoshiyuki , Kuri Zen-ichiro 
Published: July 2006

Abstract
The radiolysis of isobutane-propane (less than 5 mol %) or neopentane-alkane (5 mol%) mixtures has been studied at 77 K by means of ESR spectroscopy. When these alkane mixtures are γ-irradiated, the solute radicals are mainly formed by energy transfer from γ-irradiated isobutane or neopentane to the solutes. It is discussed whether the energy transfer is due to a proton transfer, a positive-charge transfer, or an excitation transfer, and it is concluded, for the following reasons, that the energy tranfser is probably due to the excitation transfer and that the excitation transfer may occur via highly-excited states of isobutane or neopentane; (i) The ionization potentials and the energies of the first singlet-excited states of the some additives are higher than those of isobutane or neopentane. (ii) The decrease in the solvent radical yields and the increase in the solute radical yields upon the addition of the solutes to the isobutane or neopentane amount approximately to 2–2.5 G-units. (iii) The yields of hydrogen increase sharply upon the addition of cyclopentane in the radiolysis of solid neopentane. (iv) It was concluded in previous studies that the formation of the solvent radical in the radiolysis of solid isobutane is due to the fragmentation of excited isobutane produced directly by γ-irradiation.
Line Shapes of the 35Cl Nuclear Quadrupole Resonance in KClO3, AgClO3, Ba(ClO3)2·H2O, and Cu(ClO3)2·6H2O
Authors: Suhara Masahiko , Shimizu Ken-ichi 
Published: July 2006

Abstract
The nuclear quadrupole resonance(NQR) of 35Cl in KClO3, AgClO3, Ba(ClO3)2·H2O, and Cu(ClO3)2·6H2O at room temperature has been measured by using a spectrometer system capable of reproducing with fidelity the line shape. The line-shape parameters were determined from the observed spectrum. All the line shapes of the four chlorates are of an intermediate character between Gaussian and Lorentzian. The line-width in K and Ag salts seems to originate from the inhomogeneity of the electric-field gradient, itself a result of the imperfection of the crystal. In Ba salt, it was found that the line-width is determined by the magnetic dipole-dipole interaction between chlorine and protons in the water of crystallization. The Lorentzian is the superior component of the line shape in Gu salt. This is explained in terms of the anharmonicity of the torsional oscillation of the ClO3− group.