bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of MoO3–Al2O3 Catalyst in Ethylene Polymerization. III. The Nature of Mo(V) and Its Relation with Activity
Authors: Hashimoto Keizi , Watanabe Shozi , Tarama Kimio 
Published: July 2006

Abstract
In order to determine the active center of ethylene polymerization over MoO3–Al2O3, the g-tensor and the amount of molybdenum(V) in each chemical state were determined by means of ESR measurement. The anisotropy of the g-tensor revealed the strength of the crystal field in the state; the decreasing order of the strengths was as follows: state(S)&gt;state(M)&gt;state(W)&gt;MoO3–SiO2\fallingdotseqfree MoO3. In the state(S) molybdenum oxide is insoluble in aq.10M–NH3, in the state(M) it is soluble in aq. NH3 but insoluble in water, and in the state(W) it is soluble in water. The amount of molybdenum(V) in the state(W) was studied in connection with the activity, because only the state(W) was suitable for polymerization. The behavior of the activity was in fair agreement with that of the molybdenum(V) content in the state(W) and this content depedned on the amount of supported MoO3 and on the extent of reduction. The amount of molybdenum(V) in the state(W) corresponded to the amount of chemisorbed hydrogen, which was a polymerization initiator. The chemisorption of oxygen on the catalyst caused a complete disappearance of both the activity and the molybdenum(V) content in the state(W). Therefore, it was concluded that the active center of the polymerization was molybdenum(V) in the state(W).
Analytical Application of Catalytic Polarographic Current of Nickel(II) in Acidified Thiocyanate Solutions Containing Cobalt(II)
Authors: Itabashi Eiki , Yusa Ikuko 
Published: July 2006

Abstract
Simple and sensitive methods have been developed for the determination of nickel(II), based on the catalytic polarographic current in acidic thiocyanate solution in the presence and absence of cobalt(II). The basis of the methods and the effect of variables have been investigated and elucidated. In the absence of cobalt(II), thiocyanate solution containing large amounts of hydrogen ions serves a supporting electrolyte, while an acidic thiocyanate solution containing tetra-n-butylammonium salts is suitable for the determination of nickel(II) in the presence of cobalt(II). These methods are applicable to the determination 2×10−6 M nickel(II) in the presence and absence of 1×103 M cobalt(II).
An Investigation of the Triplet State Dynamics of p-Chloroaniline by Microwave Induced Changes in the Phosphorescence Intensity and by Triplet←Singlet Absorption
Authors: Nishi Nobuyuki , Kinoshita Minoru 
Published: July 2006

Abstract
The phosphorescent triplet state T1 of p-chloroaniline (PCA) in a p-xylene host, in a neat crystal (n-trap), and in a PCA crystal doped with p-dichlorobenzene (x-trap) has been studied with the aid of phosphorescence spectra, optically detected zero-field magnetic resonance, and T1←S0 absorption spectra at temperatures below 4.2 K. The dynamic properties, particularly the radiative properties, of the individual spin states of T1 are discussed in detail using the emission spectra for each spin state obtained with microwave techniques. For the x-trap system, the emissions from the Ty and Tz sublevels are found to be coincident in contrast to the other two systems. From this observation, it is suggested that the characters of the Ty and Tz states of normal PCA are mixed together in the x-trap.
The populating rates for the individual spin states were examined for the PCA crystal systems as a function of the excitation energy, when the excitation was induced by light having wavelengths in the T1←S0 absorption region. The relative populating rates thus obtained are dependent on the excitation energy. Therefore, it is concluded that the spin alignment produced by direct optical pumping from the ground state to the triplet manifold of the crystal is conserved during the vibrational relaxation and energy transfer processes. By using this unique wavelength dependence of the populating rates, the nature of the n- and x-traps is discussed and the vibrational structure of the T1←S0 spectrum is analyzed.
The Conformations of Oligosaccharides. III. The Crystal and Molecular Structure of Melibiose Monohydrate
Authors: Hirotsu Ken , Higuchi Taiichi 
Published: July 2006

Abstract
The crystal structure of α-melibiose monohydrate (C12H22O11·H2O) was determined by direct methods using two-dimensional cosine invariants. The space group is P212121, with Z=4 and unit cell dimensions of a=15.814(5), b=10.924(5), c=8.903(4) Å. The structure was refined to R=0.044 for 1439 reflections measured with MoKα radiation. Difference synthesis indicated the partial (15%) random substitution of α-melibiose molecules by the β-anomer. The molecular conformation of α-melibiose is almost the same as that previously found in the melibiose moiety of raffinose, although some of the bond lengths and angles are significantly different. The molecules are linked by complex hydrogen-bond systems which consist of six-link finite chains and five-membered closed loops.
Studies of the Ruthenium(III) Complexes. XII Kinetic Studies of the Deammonation-anation Reactions of Halogenopentaammineruthenium (III) Complexes in the Solid State
Authors: Ohyoshi Akira , Kohata Susumu , Nishimori Masanobu , Shimura Yoshiaki , Iwasaki Noriko 
Published: July 2006

Abstract
The kinetics of the thermal substitution reaction of chloro- and bromopentaammineruthenium(III) complexes has been studied in the solid state. The reaction rates and kinetic parameters were determined for these reactions: [RuX(NH3)5]Y2(s)→[RuXY(NH3)4]Y(s)+NH3(g), and (X=Cl, Br: Y=Cl, Br, I, NO3). The values of the rate constant (s−1), the activation energy (kcal mol−1), and the activation entropy (cal mol−1 K−1) were 1.70×10−5 (at 222 °C), 41.8, and 0.7 for [RuCl(NH3)5]Cl2; 1.02×10−4 (at 226 °C), 30.2, and −19.6 for [RuCl(NH3)5]Br2; 1.35×10−4 (at 208 °C), 25.3, and −26.6 for [RuCl(NH3)5]I2; 8.47×10−3 (at 162°C), 29.7, and −11.5 for [RuCl(NH3)5](NO3)2; 1.26×10−4 (at 219 °C), 21.8, and −35.1 for [RuBr(NH3)5]Cl2, and 1.17×10−3 (at 162 °C), 14.7, and −40.0 for [RuBr(NH3)5](NO3)2 respectively. The SN1-like mechanism is favorable for the deammonation-anation reaction of all the chloropentaamine series except for the iodide, while the SN2-like mechanism is more probable for the corresponding reaction of the bromopentaammine series. The reaction mechanism is predominantly controlled by the coordinating ability of the inner-sphere halide ion and secondarily by that of the outer-sphere anion.
The Complexing of the Thallium(I) Ion with Other Solvents in Acetonitrile. Investigation Using a Cationsensitive Glass Electrode
Authors: Nakamura Toshio 
Published: July 2006

Abstract
The complexing of the thallium(I) ion with other common solvents has been studied in acetonitrile by using a univalent cation-sensitive glass electrode. A method similar to that developed to study the complexing of sodium and lithium ions was employed. Mono-, di-, and tri-solvated species were formed with DMF, SDMF, DMA, pyridine, formamide, and DMSO. Tetra-solvated species were also formed with N-methylformamide and HMPA. The complex formation constants for the mono-solvated thallium(I) ion were 4.1 with DMF, 5.6 with SDMF, 6.9 with DMA, 11 with pyridine and formamide, 12 with N-methylformamide, 15 with DMSO, and 1.0×102 with HMPA. Prior to these experiments, the cation-sensitive glass electrode was confirmed to respond to the thallium-(I)-ion activity in different solvents by comparing its behavior with that of a thallium-amalgam electrode. When water was the complexing solvent the potential of the glass electrode was not stable, and therefore, a thallium-amalgam electrode was used instead of a glass electrode to obtain the hydration constants of the thallium(I) ion in acetonitrile. Mono- and di-solvated species were formed with water and the hydration constant for the mono-solvated species was 1.1. The amalgam electrode and the glass electrode were used to obtain the constants with DMSO.
Reactions of the Di-μ-oxo-bis[aquaoxalatooxomolybdate(V)] Ion
Authors: Komura Akitoshi , Ikeda Yasuzi , Imanaga Hiroto 
Published: July 2006

Abstract
Reactions of the complex ion [Mo2O4(C2O4)2(H2O)2]2− (I) have been investigated. On acidification with perchloric acid and hydrochloric acid, complex (I) gave molybdenum(V) aqua-dimer ion [Mo2O4(H2O)6]2+, which was converted into the monomeric species [MoOCl5]2− in concentrated hydrochloric acid. The initial reaction of complex (I) with mercaptoacetic acid, giving a complex of stoichiometry 1 ligand: 1 Mo, was followed by a slower reaction which probably gave higher complexes. In the reactions with o-aminophenol and 2,2′-bipyridyl, complexes of stoichiometry 1 ligand: 1 Mo and 1 ligand: 2 Mo, respectively, were formed in solutions. The following complexes have been isolated: Mo2O4(dtc)2, Mo2O3(dtc)4 (dtc=diethyldithiocarbamate), MoOCl3. phen (phen=1,10-phenanthroline), and Mo2O3Cl4(bpy)2 (bpy=2,2′-bipyridyl). The infrared and electronic spectra of the complexes and their probable structures are given. The relative ease of replacement of ligands from complex (I) has been discussed.
Liquid Phase Disproportionation of Propylene over MoO3–Al2O3Catalyst in the Presence of Solvents
Authors: Ogata Eisuke , Sodesawa Toshiaki , Kamiya Yoshio 
Published: July 2006

Abstract
Liquid phase disproportionation of propylene using hydrocarbon solvents over MoO3–Al2O3 (atomic ratio: Mo/Al=1⁄25) catalyst was investigated at 80 °C at a pressure of 50 kg/cm2. The catalytic activity in heptane solution was preserved for a long time, because the small amount of polyolefins produced by polymerization reactions was entirely dissolved in the heptane and carried away from the catalyst surface. Selectivity for ethylene and butenes increased slightly in the heptane solvent. Benzene was not a suitable solvent because of poor solubility of the polymers and the formation of alkylbenzenes. A small amount of dissolved hydrogen also was found to be somewhat effective in lengthening the catalyst life. The polymers were found to be composed of larger amounts of ethylene than propylene and to have two molecular weight distribution maxima.
Cyanamide Derivatives. Part 99. Electrolytic Oxidation of Cyanamide
Authors: Kubo Koji , Nonaka Tsutomu , Odo Keijiro 
Published: July 2006

Abstract
Cyanamide was electrochemically oxidized with a platinum anode in aqueous potassium hydroxide. Electrolysis was carried out at 1.30 V vs. SCE of anode potential. Oxidation products consist of several unknown 1,2,3,5-tetrazine compounds and known linear cyano compounds.
Vinyl Polymerization. 341. A Proposal of a Mechanism for Radical Polymerization of Vinyl Monomers with Sodium Polymethallylsulfonate
Authors: Imoto Minoru , Nakamura Yoshiaki , Ouchi Tatsuro 
Published: July 2006

Abstract
In aqueous solution, sodium polymethallylsulfonate (PMAS-Na) can initiate a radical polymerization of vinyl monomer which has positively charged vinyl group. In the polymerization of MMA, Michaelis-Menten equation was applicable. From the results obtained, a bimolecular initiation mechanism, involving hydrogen atom transfer, was concluded to be reasonable. The relationships between pH of the aqueous layer and conversion and between polymerization temperature and conversion were of downward bell type. By Stewart model, it was found that PMAS-Na has a very rigid conformation. This structure can be compared with a rigid tertiary structure of enzyme, and the reaction appearances of enzyme and PMAS-Na can be considered to resemble very much each other.
The Reaction between Hydrocarbon and Hydrogen Chloride in Silent Electrical Discharge. I. The Reaction of Ethylene with Hydrogen Chloride
Authors: Kawamoto Kazuaki , Tamura Keiko , Hikasa Setsuko 
Published: July 2006

Abstract
Silent discharge was found to induce the reaction of ethylene and hydrogen chloride and to give mainly addition and telomerization products. Discharge on a mixture of ethylene and hydrogen chloride in an ozonizer under atmospheric pressure gave chloroethane, 1-chlorobutane, and 1,4-dichlorobutane as the main products. Besides these compounds, chloroethylene, 2-chlorobutane, 1,3-dichlorobutane, 2,3-dichlorobutane, 1,2-dichlorobutane, 1-chlorohexane, 1,2-dichloroethane, and gaseous products were also formed. The maximum yield of the liquid products was obtained when ethylene and hydrogen chloride were mixed in the ratio of approximately 1:1. The formation of telomers was favored by a low ratio of the hydrogen chloride to the ethylene concentration, and by a low temperature in the discharge reaction. On the other hand, gaseous products increased with the rise in the discharge temperature and with an increase in the ratio of ethylene to hydrogen chloride. Judging from the product distribution, the reaction may be explained in terms of radical reactions involving vinyl, ethyl, and chlorine radicals. Among the reactions between ethylene and HX, such as hydrogen cyanide, hydrogen sulfide, and hydrogen chloride, the highest conversion was obtained by using the hydrogen chloride as the reactant.
The Base-Catalyzed Condensation Reaction of o-Nitroisobutyrophenone in Liquid Ammonia
Authors: Yamaguchi Kimiko 
Published: July 2006

Abstract
The base-catalyzed condensation reaction of o-nitroisobutyrophenone (III) with sodium acetylide in liquid ammonia gave 1-ethynyl-2-methyl-1-(o-nitrophenyl)-1-propanol (G) as the main product and o,o′-azoxybenzamide (C), 2-carbamoyl-2′-carboxyazoxybenzene (C′), 2,2-dimethyl-3-indolinone (D), 1-hydroxy-2,2-dimethyl-3-indolinone (E), and 1-hydroxy-2,2-dimethyl-1,2-dihydro-4-quinazolone (F) as minor products. On the other hand, with sodium amide the ketone (III) gave Compounds C and C′ as the main products and Compounds D, E, and F as the minor products. These products were formed by the α-proton abstraction.
Transbutylation of Aromatic Hydrocarbons with Di-t-butylanisole
Authors: Shimada Keizo 
Published: July 2006

Abstract
The trans-t-butylation of aromatic hydrocarbons with di-t-butylanisole in the presence of aluminum chloride was studied. It was found that the t-butyl group substituted at the ortho position to the methoxy group transfered easily to the hydrocarbons, but the t-butyl group of the para position did not transfer to the hydrocarbons. The transbutylation products did not suffer further isomerization when the catalyst aluminum chloride was less than 1/2 mol of the di-t-butylanisole used. Competitive trans-t-butylation was carried out and kT⁄kB, km–X⁄kB, kO–X⁄kB, and kEB⁄kB were found to be 24, 2.2, 136, and 19, respectively.
N-Allylpyrazole as a Ligand. II. The Preparation and Reaction of Some Palladium(II) and Platinum (II) Complexes
Authors: Miyamoto Takeshi , Fukushima Kazuo , Saito Taro , Sasaki Yukiyoshi 
Published: July 2006

Abstract
New complexes of N-allylpyrazole(L) with Pd(II) and Pt(II) have been prepared and characterized; they have the general formulae of MX2L2 and MX2L (X=Cl or Br). IR and 1H NMR studies indicate that the latter complexes are cis-planar-chelate and involve both the pyrazolyl nitrogen and the olefinic group in bonding to the metal, while the former are syn- and anti-trans-planar and contain only uni-dentate pyrazole donor ligands. The treatment of the chelate complex PtCl2L(L=1-(2-methylallyl)-3,4,5-trimethylpyrazole) with donor ligands (L′) such as phosphines, AsPh3, and py displaces the coordinated olefin,forming cis-PtCl2LL′ with a retention of the cis-configuration.
Synthesis of Pseudo-β-Dl-galactopyranose and Pseudo-α-Dl-altropyranose
Authors: Suami Tetsuo , Ogawa Seiichiro , Ishibashi Takashi , Kasahara Isamu 
Published: July 2006

Abstract
Pseudo-β-Dl-galactopyranose and pseudo-α-Dl-altropyranose pentaacetates (10 and 11) were obtained in a seven step reaction starting from Dl-1,2-O-cyclohexylidene-5-deoxy-chiro-inositol (2).
1H-2,3-Benzoxazin-1-ones. II. Action of Amines, Phenylhydrazine, Aluminium Chloride, and Grignard Reagents on 4-Aryl-1H-2,3-benzoxazin-1-ones
Authors: Fahmy A F M , Aly Nawal F 
Published: July 2006

Abstract
4-Aryl-1H-2,3-benzoxazin-1-one on reaction with amines by fusion gave o-aroyl benzamides. With benzylamine in benzene they gave (2-benzylcarbamoyl)-benzophenone oximes, and with phenylhydrazine they gave 1,3-diaryl-1,2-dihydrophthalazin-4-ones. However, with anhydrous AlCl3 (12 mol) in reactive hydrocarbon substrates, they gave the corresponding o-aroylbenzophenone anils. With Grignard reagents they gave the corresponding o-aroyl-triaryl-methanols, which upon cyclization gave 1,1,4-triaryl-1(H)-2,3-benzoxazines.
Nuclear Magnetic Resonance Studies of Bicyclic Thiophene Derivatives. IV. Further Examples of Through-space H–F Coupling
Authors: Hirohashi Toshiyuki , Inaba Shigeho , Yamamoto Hisao 
Published: July 2006

Abstract
Bicyclic thiophene derivatives, 3-methyl-4-(o-fluorophenyl)-2,3-dihydrothieno[2,3-d]-pyrimidin-2-ones (I) and N,5-dimethyl-4-(o-fluorophenyl)-5H-thieno[2,3-c]-pyrrole-6-carboxamides (II), have been prepared. Two sorts of 1H, 19F spin coupling over six bonds attributable to a through-space mechanism have been observed in the 1H NMR spectra of these compounds.
Polarographic Studies on Bipyridine Complexes. IV. The Polarography of the Dicyanobis(2,2′-bipyridine)iron(II) Complex
Authors: Saji Tetsuo , Aoyagui Shigeru 
Published: July 2006

Abstract
Each electron added to the oxidant in the first two reduction waves of a polarogram for dicyanobis(2,2′-bipyridine)iron(II) is concluded to occupy a π*-orbital localized on a bipyridine molecule, on the basis of the number of the reversible waves and the half-wave potential shift caused by the methyl substitution of ligand bipyridines.
Studies of the π→π* Absorption Bands of 1,2-Naphthoquinone
Authors: Kuboyama Akira , Arano Hiroshi 
Published: July 2006

Abstract
The π→π* S–S absorption spectra up to the vacuum UV region of 1,2-naphthoquinone in solutions were obtained. Based on MO calculations, the observed five π→π* bands of 1,2-naphthoquinone are assigned, and the alkyl-group substitution effects on the excitation energy of the longest-wavelength π→π* band are discussed.
Magnetic Susceptibility of Perylene-Iodine Complex
Authors: Kinoshita Minoru , Kanda Hisao , Akamatu Hideo 
Published: July 2006

Abstract
The magnetic susceptibility of a highly conductive 2 : 3 charge-transfer complex of perylene with iodine has been examined as a function of temperature. The paramagnetic susceptibility, which was found to be nearly independent of temperature, is considered to be due only to the perylene cation radical.
The Photoconductivity of Poly(N-vinylcarbazole). VII. The Effect of the Singlet and Triplet Quenchers on the Photoconductivity
Authors: Okamoto Ken-ichi , Oda Norikazu , Itaya Akira , Kusabayashi Shigekazu 
Published: July 2006

Abstract
The singlet quenchers significantly reduce the photocurrents of poly(N-vinylcarbazole) and of brominated poly(N-vinylcarbazole), but the triplet quenchers do not do so at all regardless of the high efficiency of the polymer-to-quencher triplet energy transfer. This result excludes the possibility of the photocarrier generation from the triplet excited state in these polymers.
Rate of Protonation of TCNQ Anion Radical in Water
Authors: Yamagishi Akihiko 
Published: July 2006

Abstract
The protonation of TCNQ, anion radical has been studied with an oxygen-free stopped-flow apparatus. The protonation rate is proportional to the square of TCNQ\ewdot concentration, being independent of the proton concentration. It is suggested that there exists an intramolecular step in which the electronic structure of TCNQ\ewdot changes into another one ready to accept a proton.
The Preparation and the Magnetic Property of Bis(N-o-nitrophenylsalicylideneaminato)copper(II)
Authors: Tokii Tadashi , Ohno Norimitsu , Muto Yoneichiro 
Published: July 2006

Abstract
A synthesis of bis(N-o-nitrophenylsalicylideneaminato)copper(II) is reported. The magnetic properties of the complex and the corresponding p-nitro complex are discussed in terms of the steric effect of the nitro group.
Radical Anions Derived from 4-Picrylimino-2,6-disubstituted-2,5-cyclohexadiene-1-one
Authors: Manda Eiichiro , Shimura Takehiko 
Published: July 2006

Abstract
4-Picrylimino-2,6-di-t-butyl (or bromo)-2,5-cyclohexadiene-1-ones were synthesized and radical anions were derived from them by one electron reduction with potassium metal. ESR measurement showed that an odd electron exists mainly on the quinone-imine moiety of the radical anion molecule.
Bis(acetylacetonato)metal(II)-Catalyzed Addition of Acceptor Molecules to Acetylacetone
Authors: Uehara Kaku , Ohashi Yoshiyuki , Tanaka Makoto 
Published: July 2006

Abstract
Bis(acetylacetonato)metal(II) (M(acac)2) showed an effective catalytic activity for the addition of various acceptor molecules to acetylacetone to give 3-substituted 2,4-pentanediones.
Enzyme-like Reaction Catalyzed by Flavin-Reduced Keratin Systems. II. Binding Site in FAD-Reduced Keratin Complex
Authors: Takahashi Fujio , Ogasa Tatsuo , Rahman M B 
Published: July 2006

Abstract
In order to confirm the binding site in the FAD-reduced keratin (RK) complex, polarographic and fluorometric studies were carried out and the FAD–RK complex was isolated. An adenine moiety of FAD was found to form a 1:1 complex with RK.
Oxosulfonium Salts. IV. Preparation and Reactions of Methylphenyloxosulfonium Methylide
Authors: Ryoke Katsumi , Minato Hiroshi , Kobayashi Michio 
Published: July 2006

Abstract
Methylphenyloxosulfonium methylide was synthesized, and its reactions with several substrates possessing C=C and C=O bonds were investigated.
Shock Tube Studies of the Rate Constant for Chemical Excitation of Hydroxyl Radicals
Authors: Koike Tohru , Morinaga Kihei 
Published: July 2006

Abstract
The OH(2Σ+2-Π) chemiluminescence in the partial equilibrium region of the H2–O2 reaction in mixtures with H2/O2/Ar=2/2/96, P1=5, 10, 20 Torr was studied in 1250–2000 K incident shock waves. The comparison between the temperature dependence of the OH(2Σ+) emission and that of the computer simulation of the H2–O2 reaction yields the activation energy of the chemical excitation process, assuming the same bi-radical process as former investigators used. The evaluated OH(2Σ+) profile, based on a simulation in which the chemical excitation, radiative, and non-radiative processes are accounted for, depends on the pre-exponential factor of the chemical excitation process. The correlations between the temperature dependence of the evaluated OH(2Σ+) profile and that of the emission profile in the partial equilibrium region gave the pre-exponential factor of the chemical excitation process. Thus, we could estimate the rate constant for O+H+Ar=OH(2Σ+)+Ar to be 1.0×109×exp(−11000 cal⁄RT).
Transition Dipole Interaction and Intermolecular Potential of Carbon Disulfide and Sulfur Dioxide Crystals
Authors: Kuroda Yoshihiro , Machida Katsunosuke 
Published: July 2006

Abstract
The optical active normal frequencies and the heats of sublimation of carbon disulfide and sulfur dioxide crystals have been calculated. The interaction between the transition dipoles associated with the infrared active intermolecular modes has been taken into account by introducing coupling terms between the equivalent coordinates of neighboring molecules. The coupling force constants estimated from the infrared absorption intensities explain the observed trend of the factor group splittings of the ν3 mode of carbon disulfide and the ν1 and ν3 modes of sulfur dioxide. The splitting of the ν2 mode of carbon disulfide has been reproduced by taking account of the long range Coulomb interaction between the atomic charges.