bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Remarks on the Reaction Mechanism and Kinetic Rate Constants for the Pentacyanocobaltate(II)-catalyzed Hydrogenation of Olefins Using the Iterative Simulation Technique
Authors: Ohkubo Katsutoshi , Tsughihashi Kohji , Ikebe Hiromichi , Sakamoto Hiroyuki 
Published: July 2006

Abstract
The reaction mechanism and kinetic-rate constants of the pentacyanocobaltate(II)-catalyzed hydrogenation of olefins were investigated. The present study with an iterative simulation technique supported the Co(CN)53−+H2→Co(CN)5H3−+H· and Co(CN)53−+H·→Co(CN)5H3− reactions for the uptake of H2 by the cobaltate(II) during the initial stage of the reaction. An examination was also made of the stationary-state approximation used for the kinetic analysis of the reaction.
Electronic Structures of Excited States of Benzoquinolines
Authors: Yamaguchi Hiroyuki , Ikeda Teruki , Mametsuka Hiroaki 
Published: July 2006

Abstract
Measurements of the dipole moments and acidity constants in the lowest excited singlet states for benzo[c]quinoline, benzo[f]quinoline, and benzo[h]quinoline have been carried out by spectrophotometry. The electronic structures of excited states have been calculated by using the semi-empirical SCF–π–MO CI method, which allows for a bond order-bond length relationship at each iteration. The experimentally-determined dipole moments and acidity constants can not be correlated to the calculated electronic structures of the Franck-Condon states, but they can be correlated to the calculated structures of the equilibrium states for the lowest excited singlet states of three isomeric benzoquinolines.
The Absorption and Fluorescence Spectra of 2-Methyl-1-aceanthrenone and Its Cation. A Comparison with 9-Anthracenecarboxaldehyde
Authors: Hirayama Satoshi 
Published: July 2006

Abstract
The fluorescence and absorption spectra of 2-methyl-1-aceanthrenone (I) and its cation were investigated. The spectra showed well-defined vibrational structures in a wide variety of solvents, but not in ethyl alcohol and acetic acid. The existence of the 1Lb absorption band on the shorter-wavelength side of the 1La band was strongly supported by the different solvent effects of these bands. In non-polar solvents, (I) formed a strongly fluorescent, 1:1, hydrogen-bonded complex with a trichloroacetic acid molecule. The formation constant in n-hexane was determined spectrophotometrically as 3.1×10−2 M−1 at 20 °C. In acidic solutions, pKa and pKa*, were determined as −5.1 and 1.3 for the ground and first excited singlet states respectively. These values are the same as the corresponding values of 9-anthracenecarboxaldehyde (9-CHO-A), reflecting a marked resemblance in the electronic nature of the carbonyl groups of the two compounds. The broad absorption spectra of 9-CHO-A, in contrast to the highly structured spectra of (I), are due to a feasible torsional motion of the carbonyl group of the former compound.
Photoemission from Pyrene and its Derivatives
Authors: Hino Shojun , Hirooka Tomohiko , Inokuchi Hiroo 
Published: July 2006

Abstract
Photoemissions from pyrene and its derivatives, 1,3,6,8-tetrachloropyrene(TClP), 1,3,6,8-tetrabromopyrene(TBrP), 1,6-dicyanopyrene(CDNP), 1,3,6,8-tetracyanopyrene(TCNP), and 1,3,6,8-tetranitropyrene (TNO2P), were measured. Their photoelectron energy distribution curves(EDCs) were thus obtained; the peaks or shoulder appearing on the EDCs correspond to the ionization potentials of the pyrene molecule. Further, the spectral dependences of their quantum yields(SDQYs) were measured. The ionization potentials obtained from their threshold values were 5.8 eV(pyrene), 6.3 eV(TClP), 6.0 eV (TBrP), 6.3 eV(DCNP), 6.2 eV(TCNP), and 6.6 eV(TNO2P).
The Analysis of the Molecular Vibration by the Molecular Orbital Method. I. Application to HCN
Authors: Miyazaki Tomoo , Ikeda Masaru , Shibata Masayuki 
Published: July 2006

Abstract
The approximate self-consistent molecular orbital method has been applied to the analysis of the vibrational spectrum of HCN. The frequencies of the fundamental, overtone, and combination bands in the region from about 700 to 12000 cm−1 have been calculated, and their absolute infrared absorption intensities have been estimated, the variational method being used in this calculation. Also, the frequencies and absorption intensities of hot bands, referring to the bending vibration, have been calculated. In comparison with the experimental results, the calculated frequencies were not always appropriate. However, it was found that these results are effective in the analysis of the molecular vibration if the calculated frequencies are discussed along with their infrared absorption intensities.
Effects of Anionic and Cationic Surfactants on the Ion Flotation of Cu2+
Authors: Kobayashi Koichi 
Published: July 2006

Abstract
The effects of several anionic surfactants—sodium α-sulfolaurate, sodium laurate, sodium dodecylsulfate, and cationic surfactants, dodecylpyridinium chloride, and dodecyltrimethylammonium chloride—on the bubble flotation of Cu2+ ions were studied. Sodium α-sulfolaurate was found to be most effective for the flotation of Cu2+ ions. The flotation rate (percent removed) increased sharply from zero at about pH 6, and a rate larger than 95% was attained in the pH region of about 7 to 11. Cationic surfactants alone could float Cu2+ ions only slightly. They floated most of the Cu2+ ions upon the addition of bentonite, however. A flotation rate of about 90% was attained in the pH region larger than about 6. This was explained by the Cu2+ ions being removed as polynuclear species, which combined directly with an anionic surfactant or a cationic surfactant with the aid of bentonite.
The Role of the Promoting Mode in Nonradiative Transitions in Large Molecules
Authors: Fujimura Yuichi , Nakajima Takeshi 
Published: July 2006

Abstract
A rate expression for the intramolecular nonradiative transition where a promoting mode acts also as an accepting mode at the same time has been derived within the statistical limit. The dependence of the nonradiative transition rate on the shift of the equilibrium point of the promoting mode in the relevant electronic states, Δp, has been examined for two cases, i) excited \ightsquigarrow ground states and ii) excited \ightsquigarrow excited states, in aromatic hydrocarbons which satisfy the above condition.
Diffusion and Adsorption of a Model Cationic Dye, m-Nitrobenzylamine, in Polyacrylonitrile
Authors: Morita Zenzo , Hossain T M Abul , Iijima Toshiro 
Published: July 2006

Abstract
A model cationic dye, m-nitrobenzylamine (NBA), was synthesized, and the diffusion and adsorption behavior in polyacrylonitrile was investigated by the cylindrical film roll method. pKa of NBA was determined spectroscopically to be 9.2 at 25 °C. The diffusion was concentration dependent and was described by the chemical potential gradient model. The temperature dependence of the diffusion coefficients above Tg, which was found to be 65 °C from the inflection point of Arrhenius plot, could be described by WLF equation, where C1g and C2g are 1.64 and 17.09 (deg.) at pH 4.2, and 2.41 and 33.11 (deg.) at pH 6.8, respectively. Adsorption isotherm of NBA was obtained at 95 °C and pH 1.5, 4.2 and 6.8. The adsorption of NBA, bis(m-nitrobenzyl)amine and Malachite Green at pH 4.2 and those of NBA and bis(m-nitrobenzyl)amine at pH 6.8 were more or less the same. It is concluded that the adsorption of cationic compounds on polyacrylonitrile is virtually dependent upon the ion exchange mechanism. But the presence of sodium chloride in the dye bath did not change the adsorption of NBA at pH 4.2 and 95 °C. The surface concentration of NBA was gradually increased with rise of temperature at pH 1.5, 4.2 and 6.8.
Laser Photochemistry. II. Determination of the ORD and CD Spectra of Some Chromium(III) β-Diketonates
Authors: Yoneda Hayami , Sakaguchi Ushio , Nakashima Yoshiaki 
Published: July 2006

Abstract
An argon ion laser has been used to partially photoresolve the following tris(β-diketonato)chromium(III) complexes; Cr(acac)3, Cr(3-X-acac)3 (X=Cl−, Br−, I−, and NO2−), Cr(tfac)3, and Cr(bzac)3, where the abbreviations are acac=acetylacetonate ion, 3-X-acac=γ-substituted acetylacetonate ion, tfac=trifluoroacetylacetonate ion, and bzac=benzoylacetonate ion. From the wavelength dependence of the steady state resolution yield, the method of photoresolution has been confirmed to allow the determination of the ORD and CD spectra of optically pure enantiomers. The ORD and CD spectra of the above-mentioned compounds are given.
Mechanism of Racemization of Octahedral Silicon(IV) Complexes with Various β-Diketones in Organic Solvents
Authors: Inoue Tomoaki , Fujita Junnosuke , Saito Kazuo 
Published: July 2006

Abstract
Silicon(IV) complexes of 4 kinds of β-diketonate have been resolved and their racemization has been kinetically studied in 1,1,2,2-tetrachloroethane (TCE) and acetonitrile (AN) at 30 to 80 °C. Ultra-violet absorption spectroscopy and isotopic exchange studies with labelled ligands verified intra-molecular mechanism. A similar rate formula to that for the tris(acetylacetonato)silicon(IV) was obtained: k0=k1+k2[acid or base]. Increase in basicity of the ligand decreases the rate. Introduction of methyl group on the central carbon of the six-membered chelate ring markedly enhanced the racemization. It seems as if the intermediate species with a unidentate ligand tends to take trans form around the C=C axis and retards the recombination, giving rise to bigger k values. Mechanism of acid and base catalysis was also discussed.
Furan Derivatives. I. On the Methods of Synthesizing Some Naphtho[1,8-bc]furans
Authors: Horaguchi Takaaki , Shimizu Takahachi , Suzuki Tsuneo 
Published: July 2006

Abstract
Two kinds of methods of synthesizing naphtho[1,8-bc]furans (Vla–VId) are described. In the first method, naphtho[1,8-bc]furans (Vla–VId) were obtained by the decarboxylation of IIa–IId, which had previously been prepared from Ia-Id and ethyl bromoacetate. The yields of IIa–IId from Ia–Id were 45, 43, 49, and 46% respectively. In the second method, VIa–VId were obtained by heating Va–Vd with acetic anhydride and sodium acetate. The yields of VIa–VId were 34, 46, 46, and 70% respectively.
Crystallographic Studies of Interaction between Nucleotides and Metal Ions. I. Crystal Structures of the 1:1 Complexes of Cobalt and Nickel with Inosine 5′-Phosphate
Authors: Aoki Katsuyuki 
Published: July 2006

Abstract
The crystal structures of the 1:1 complexes of inosine 5′-phosphate with cobalt (C10H11O8N4PCo,7H2O) and inosine 5′-phosphate with nickel(C10H11O8N4PNi,7H2O) have been determined from single-crystal X-ray data collected on an automated diffractometer. The both isomorphous crystals belong to orthorhombic system, space group P212121 with four formula units in the unit cell of dimensions a=10.859, b=25.987, c=6.845 Å for the cobalt complex and a=10.812, b=25.898, c=6.845 Å for the nickel complex respectively. The structure of the cobalt complex was determined by three-dimensional Patterson and Fourier methods and that of the nickel complex was elucidated from that of the cobalt complex. Both were refined by the block-diagonal least-squares method including anisotropic temperature factors. The final R values were 0.051 and 0.075 for the cobalt and nickel complexes, respectively. All of the 25 hydrogen atoms in the case of the cobalt complex and 22 hydrogen atoms in the case of the nickel complex were found. The hypoxanthine bases related by the two-fold screw axis parallel to c are extensively overlapped at a distance of 3.42 Å for both complexes. The nucleotides have the preferred anti conformation about the glycoside linkage with the ribose ring showing the C(3′)-endo pucker. The torsion angles around the C(5′)–O(5′) bond are 161.6° (cobalt complex) and 162.0° (nickel complex). In the both complexes, therefore, the phosphate group has the extended conformation. The metals are not directly bonded to the phosphate oxygen atoms but are bonded to the nitrogen atom N(7) of the base and to five water oxygen atoms. There is extensive hydrogen bonding involving the hypoxanthine ring, the phosphate anion, the hydroxyl groups of the furanose ring and seven water molecules in the crystal.
Selective Dimerization of Propene to 4-Methyl-1-pentene by Potassium–Copper based Catalysts
Authors: Yamashita Junzo , Sasaki Kiyoshi , Kawamura Takao , Higuchi Koichi , Miura Shotaro , Hashimoto Harukichi 
Published: July 2006

Abstract
The dimerization of propene by potassium catalyst was carried out at 180 °C in n-heptane to give 4-methyl-1-pentene as a major product. The effects of the addition of metal powders, potassium alkoxides and tertiary amines were investigated. The selective production of 4-methyl-1-pentene on adding metal powders increased in the order of Cu, Ag&gt;Mg, Co&gt;Al, Fe, Ni, Zn. When long-chain alkoxides were added to the potassium–copper catalyst system, potassium catalyst was observed to be dispersed, the relative reaction rates increased, and the isomerization of 4-methyl-1-pentene formed was retarded. Thus, the selectivity increased more than 90% after 40% conversion of propene. The potassium–copper–aliphatic tertiary amine-catalyst system caused the yield of 4-methyl-1-pentene to increase in a similar manner to the potassium–copper–alkoxide-catalyst system and inhibited the formation of the carbonaceous substance covering the surface of the catalyst, and the selectivity was not lowered after a higher conversion of propene.
The Reaction of Cycloalkanones with Copper(II) Halides. I. The Reaction of Cyclohexanones with Copper(II) Chloride
Authors: Nishizawa Kyoko , Satoh J Yasuo 
Published: July 2006

Abstract
The reaction of cyclohexanones with copper(II) chloride gave polychlorinated cyclohexanediones directly in fairly good yields. With methylcyclohexanones, in general the type of product depends on the number of methylene groups between the carbonyl group and the methyl-substituted carbon in the starting material. A possible mechanism for the reaction is discussed.
Vinyl Polymerization. 327. Determination of the Initiating Radical Species in Polymerization with a Dimethylmercury and Copper(II)-Ion System
Authors: Imoto Minoru , Nakamura Yoshiaki , Ouchi Tatsuro 
Published: July 2006

Abstract
Dimethylmercury was found to give a methyl radical (·CH3) by the reaction with Cu(II)-ion in the presence of water. Generation of ·CH3 was proved by scavenging with 1,3,5,-triphenylverdazyl. Radical polymerization of methyl methacrylate and acrylonitrile was carried out with the system dimethylmercury/water/Cu(II)or Fe(III)-ion.
A-Substituted 5β-Steroids. VII. The Polyhalogenation of 5β-Cholestan-2-one
Authors: Satoh J Yasuo , Horiuchi C Akira , Hagitani Akira 
Published: July 2006

Abstract
The polyhalogenation of 5β-cholestan-2-one (I) in acetic acid containing hydrogen halide occurs in this positional order: C1→C3→C3 and finally at C1, which has the largest steric hindrance. The tetrahalogenation of the ketone (I) yields 1,1,3,3-tetrachloro-5β-cholestan-2-one (IXb), but fails to give the tetrabromo derivative; rather, it yields 1β,3,3-tribromo-5β-cholestan-2-one (Va), 1,1,3-tribromo-5β-cholest-3-en-2-one (VIIIa), and 1β,3-dibromo-5β-cholest-3-en-2-one (VIa). The conformations of the dihalo-, the trihalo-, and the tetrachloroketone derivatives are discussed in connection with the ORD, CD, IR, and NMR spectra.
The Effects of Substituents and Solvents on the Structure of Fluorenyl and Cyclopentadienyl Salts
Authors: Tomoi Masao , Yoneyama Toshio , Kakiuchi Hiroshi 
Published: July 2006

Abstract
The electronic spectra of 9-(ω-methoxyalkyl) and 9-(ω-dimethylaminoalkyl)fluorenyl salts of alkali cations were measured in ethereal solvents. The relative amounts of the contract ion pairs connected with the 9-substitu-ents (R) decreased in this order: R=(CH3)2N–(CH2)2–&gt;CH3O–(CH2)2–&gt;CH3O–(CH2)3–&gt;(CH3)2N–(CH2)3–&gt;&gt;CH3O–(CH2)4−≈n-C4H9−. This behavior was explained in terms of the formation of an intramolecular association between the hetero atoms in the substituents and the counter ions; such an association favored the formation of the contact ion pair. The interaction of magnesium fluorenide and cyclopentadienide with hexamethylphosphoramide (HMPA) was studied by means of NMR spectroscopy in ether or tetrahydrofuran. The fluorenide changed from a covalent type to a solvent-separated ion pair by the coordination of three HMPA with the magnesium. The cyclopentadienide was proposed to change from a contact ion pair to a solvent-separated ion pair by means of two-step process in which the cyclopentadienyl ions became successively separated from the magnesium ion.
Photosensitized Polar Addition of Acetic Acid to 4-Homoadamantene: The Behavior of the 4-Homoadamantyl Cation
Authors: Yamagughi Ryohei , Kawanisi Mituyosi 
Published: July 2006

Abstract
The photosensitized polar addition of acetic acid to 4-homoadamantene (I) gave 2,4-dehydrohomoadamantene (II), 2-adamantylmethyl acetate (IIIa), and 4-homoadamantyl acetate (IVa). The same treatment of I in pivalic acid gave analogous products, II, 2-adamantylmethyl pivalate (IIIb), and 4-homoadamantyl pivalate (IVb). It was shown that II and III were derived from the 4-homoadamantyl cation (V). On the other hand, the diazotization of 4-homoadamantylamine (XV) in the presence of acetic acid gave I, II, and IVa, whereas it has been reported that a buffered acetolysis of 4-homoadamantyl tosylate (XIV) gave I and IVa, but not II. The formation of II may be explained by assuming a different energy state of V of different origin; it proves a vibrationally excited nature of V generated in the photosensitized polar addition reaction.
The Catalytic Action of Fe(III) in the U(IV)–U(VI) Electron Exchange Reaction
Authors: Tomiyasu Hiroshi , Fukutomi Hiroshi 
Published: July 2006

Abstract
The catalytic action of ferric ions in the U(IV)–U(VI) electron exchange reaction has been studied in the presence of a high concentration of hydrochloric acid. The exchange rate is found to be accelerated by the addition of ferric ions; the observed rate law is given by:
R=k_0[U(IV)][U(VI)]+k_c[Fe(III)]_0\sqrt[U(IV)][U(VI)]
An activation energy of 19.7 kcal/mol was calculated for the iron-catalyzed reaction in the U(IV)–U(VI) electron exchange reaction. This value is much smaller than that of 32.2 kcal/mol, which was found in the non-catalytic reaction. The kinetics and equilibrium of the reaction between Fe(III) and U(IV) have also been studied in order to investigate in detail the mechanism of the catalytic reaction. A one-electron-transfer mechanism producing U(V) as an intermediate is estimated from the rate law and supported by the kinetics and equilibrium studies of the Fe(III)–U(IV) reaction.
The Formation of Crystalline Complexes between Inosine and Several Hydroxybenzoic Acids
Authors: Suzuki Yoshihisa , Hara Kentaro 
Published: July 2006

Abstract
Inosine was found to form 1 : 1 crystalline complexes with 2,4-, 2,5-, 2,6-, 3,4-, 3,5-dihydroxybenzoic acids, and with 3,4,5-trihydroxybenzoic acid, but was found to give no crystalline complex with benzoic acid, o-, m-, p-hydroxybenzoic acids, 2,3-dihydroxybenzoic acid, or 2,3,4-trihydroxybenzoic acid.
On the Melting Point of N-Methylacetamide–Silver Nitrate Adduct
Authors: Matsubara Takaharu , Tanaka Toshio 
Published: July 2006

Abstract
The melting point of N-methylacetamide–silver nitrate adduct AgNO3·2NMA was found to be 46–47 °C which is in large disagreement with that reported by Paul and Chadha. The discrepancy was interpreted to result from the tendency of the adduct to lose NMA at high temperatures or at low partial pressures of NMA.
α,β-Unsaturated Carboxylic Acid Derivatives. VII. Reaction of Ethyl α,β-Unsaturated α-Cyanocarboxylates with Triethyl or Diethyl Phosphonate
Authors: Shin Chung-gi , Yonezawa Yasuchika , Sekine Yasuo , Yoshimura Juji 
Published: July 2006

Abstract
The reaction of ethyl α,β-unsaturated α-cyanocarboxylates with triethyl phosphonate gave ethyl α-cyano-β-diethoxyphosphinyl-carboxylates in about 50% yields.
Electronic Structures and Spectra of Quinarene Molecules
Authors: Yamaguchi Hiroyuki , Nakajima Takeshi 
Published: July 2006

Abstract
The electronic structures and spectra of fundamental quinarene molecules, 1–9 (Fig. 1) and some of their diphenyl derivatives (Fig. 2) have been studied by using the variable bond-length SCF LCAO-π-MO CI method.
The Allylic Rearrangement. IV. New Synthesis of 4-Hexenoic Acid
Authors: Tsuboi Sadao , Takeda Akira 
Published: July 2006

Abstract
rans-4-Hexenoic acid, a useful starting material for the synthesis of racemic 4R : 5S and 4S : 5R 4,5-dihydroxyhexanoic acid γ-lactone, one component of the aroma extracts from one Galifornian and two Spanish flor sherries, has been conveniently prepared by the Favorskii-type rearrangement of 5-chloro-3-hexen-2-one.
Potential Antitumor N-Carbamoyl-N′-methyl-N′-nitroso Derivatives of Amino Acids
Authors: Machinami Tomoya , Suami Tetsuo 
Published: July 2006

Abstract
N-Carbamoyl-N′-methyl-N′-nitroso derivatives of amino acids have been prepared by treating the amino acids with methyl isocyanate followed by nitrosation with sodium nitrite in dilute acetic acid solution.
Catalytic Transformation of Cyclohexene Hydroperoxides to Epoxy Alcohols with Vanadyl Acetylacetonate
Authors: Itoh Takashi , Kaneda Kiyotomi , Teranishi Shiichiro 
Published: July 2006

Abstract
Cyclohexene hydroperoxide and its methyl derivatives undergo rearrangement in the presence of the vanadyl acetylacetonate catalyst to the corresponding epoxyalcohols with high cis-stereoselectivity in high yields.
The Catalytic Hydrogenation of Ethylene over Calcium Hydride and the Role of the Hydrogen of the Hydride
Authors: Yamaguchi Masaru , Hiraki Yozaburo , Wada Masatada , Tarama Kimio 
Published: July 2006

Abstract
The catalytic hydrogenation of ethylene over the non-stoichiometric calcium hydride (CaH2−δ) prepared by means of high-temperature evacuation was studied. The order of introducing gases had no effect on the rate of ethylene hydrogenation. The rate expressions for the initial stage were ν=k PH0.8–1.0 PE and ν′=k′ PH0.8–1.0 PE0 in the lower and higher pressure ranges of ethylene respectively. The amount of hydrogen bound initially to CaH2−δ and participating in the reaction was estimated from the results of the D2–CaH2−δ exchange and H2–D2 equilibration reactions. From these results, the mechanism of ethylene hydrogenation over calcium hydride and the role of the hydrogen of the hydride were discussed. The poisoning caused by water and acetylene was also studied. Furthermore, the catalytic activity of calcium hydride was compared with that of three metallic hydrides.
Polarographic Reduction of Ubiquinone-10 Solubilized in Micelles
Authors: Erabi Tatsuo , Hiura Hisahide , Tanaka Masaya 
Published: July 2006

Abstract
Ubiquinone-10 solubilized in an aqueous solution containing sodium dodecyl sulfate as an anionic surfactant was polarographically investigated. Ubiquinone-10 solubilized in micelles shows a well-defined, diffusion-controlled, pH-dependent wave. Diffusion coefficient and apparent particles radii were calculated. The surfactant concentration dependence of the diffusion coefficient and of the apparent particle radii was also determined.