bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Arylthio-Substituted 3,8-Diphenyl-1,2-diazacycloocta-2,4,6,8-tetraenes and Their Thermolysis
Authors: Yogi Seiichi , Hokama Kozo , Tsuge Otohiko 
Published: July 2006

Abstract
Nucleophilic substitution of 4,7-dichloro-3,8-diphenyl-1,2-diazocine with arenethiols gave stable 4-arylthio-7-chloro- and/or 4,7-bis(arylthio)-1,2-diazocines. Unsymmetrical 4,7-bis(arylthio)- and 4-acetoxy-7-phenylthio-1,2-diazocines were also prepared from 4-chloro-7-phenylthio-1,2-diazocine. Thermolysis of all the diazocines afforded only arylthio-substituted pyridines with extrusion of benzonitrile.
Photocatalytic Oxidative Dehydrogenation of 2-Propanol with Niobium Oxide Supported on Porous Vycor Glass
Authors: Wada Yuji , Morikawa Akira 
Published: July 2006

Abstract
2-Propanol was catalytically converted to acetone on niobium oxide supported on porous Vycor glass in the presence of oxygen or nitrogen monoxide under UV irradiation. The light of wavelength shorter than 300 nm was effective for the reaction. The VIS-UV absorption measurements showed that niobium oxide was reduced by 2-propanol under the irradiation and Nb4+ formed by the photoreduction was reoxidized by oxygen. The kinetics of the reoxidation was investigated by means of spectroscopic measurements. The redox mechanism is proposed for the photocatalytic oxidation of 2-propanol.
1-3-η-Allylpalladium(II) and Platinum(II) Complexes Containing Tris(2,6-dimethoxyphenyl)phosphine Ligand
Authors: Kurosawa Hideo , Tsuboi Aki , Kawasaki Yoshikane , Wada Masanori 
Published: July 2006

Abstract
Neutral and cationic 1-3-η-(2-methylallyl) complexes of Pd and Pt containing tris(2,6-dimethoxyphenyl)phosphine (abbreviated as P(2,6)3), M(1-3-η-CH2CMeCH2)Cl{P(2,6)3} and [M(1-3-η-CH2CMeCH2){P(2,6)3}]BF4, were prepared. The latter contained a weakly coordinated OMe group of P(2,6)3 which was readily replaced by carbon monoxide to afford [M(1-3-η-CH2CMeCH2)(CO){P(2,6)3}]BF4. Owing to large steric bulk and high nucleophilicity of P(2,6)3, addition of P(2,6)3 to these complexes did not result in coordination of the second molecule of the phosphine to the metal atom but ready attack at the metal-bound 2-methylallyl and methoxyl carbon atoms to give the corresponding (2-methylallyl)phosphonium and methylphosphonium ions. From these reactions were isolated a neutral 1-3-η-(2-methylallyl)platinum(II) complex involving chelate coordination of a tertiary phosphine ligand which was derived from the loss of methyl of one methoxyl group in P(2,6)3 and the resulting phenoxo ligand, and a cationic, binuclear Pt(I) carbonyl complex bridged by the 2-methylallyl group. Also prepared in this study were 1-3-η-(2-methylallyl)(acetylacetonato) complexes of Pd and Pt, M(1-3-η-CH2CMeCH2)(acac){P(2,6)3}. In the platinum analog, the acetylacetonato ligand was suggested to coordinate to the metal in a monodentate fashion via the central carbon atom. Both complexes afforded moderate yields of CH2=CMeCH2CH(COMe)2 upon treatment with carbon monoxide, while the reaction of M(1-3-η-CH2CMeCH2)(CO){P(2,6)3}+ with sodium acetylacetonate failed to give the same coupling product.
Possible Fluorescence from the Polycyclic Aromatic Hydrocarbons in the Interstellar Medium
Authors: Aihara Jun-ichi 
Published: July 2006

Abstract
Large compact polycyclic aromatic hydrocarbons (PAHs) are photochemically very stable. These PAHs have been considered as excellent candidates for explaining the interstellar infrared emission lines. Since the large compact PAHs exhibit the first electronic absorption band in a rather low-energy region, it is possible and very probable that fluorescence from such PAHs are responsible for the red emission humps of several nebulae such as the Red Rectangle, a nebula surrounding the binary star HD 44179.
Alkaline Hydrolysis of N-Methyl-2,4-dinitroacetanilide and N-Alkyl-N-(5-nitro-2-pyridyl)acetamides
Authors: Kijima Atsushi , Sekiguchi Shizen 
Published: July 2006

Abstract
The kinetics of the alkaline hydrolysis of N-methyl-2,4-dinitroacetanilide (2), N-ethyl- (3), and N-methyl-N-(5-nitro-2-pyridyl)acetamide (4) was carried out. The reaction path consists of two stages: the first one is the rate-limiting formation of the first tetrahedral intermediate (monoanionic) and the second one the fast decomposition of the intermediate. The latter fast decomposition of the intermediate (monoanionic) involves two processes: one is the direct decomposition of the intermediate to the products and the other is a proton abstraction of the hydroxyl group of the intermediate by −OH giving the second tetrahedral intermediate (dianionic), followed by its deconposition to the products. For the alkaline hydrolysis of 2–4, the decomposition of the first intermediate occurred predominantly via the latter process.
Syntheses of Bis(vinylenedithio)tetrathiafulvalene and Bis(methylvinylenedithio)tetrathiafulvalene
Authors: Nakamura Tadashi , Iwasaka Shin-ichi , Nakano Hideyuki , Inoue Kazuhiko , Nogami Takashi , Mikawa Hiroshi 
Published: July 2006

Abstract
Bis(vinylenedithio)tetrathiafulvalene (BVDT-TTF) and bis(methylvinylenedithio)tetrathiafulvalene (BMVDT-TTF) were synthesized as attractive donor molecules for highly conductive organic salts. These molecules have analogous structures to BEDT-TTF, but are expected to possess more planar structures. They have higher oxidation potentials than BEDT-TTF. The synthetic method of BVDT-TTF by using a phase-transfer catalyst was also studied.
Molecular Recognition in the Formation of Conglomerate Crystal. The Role of Cinnamic Acid in the Conglomerate Crystals of 1-Phenylethylamine and 1-(4-Isopropylphenyl)ethylamine Salts
Authors: Saigo Kazuhiko , Kimoto Hiroki , Nohira Hiroyuki , Yanagi Kazunori , Hasegawa Masaki 
Published: July 2006

Abstract
The Crystal structures of (+)-1-phenylethylamine·cinnamic acid salt and (+)-1-(4-isopropylphenyl)ethylamine·cinnamic acid salt were determined by X-ray analysis. The crystal structures of these two salts provided for the first time some insights into the mechanism of the formation of a conglomerate crystal. In each crytal, two amine components and two acid components form a helical column by hydrogen bonds. On the basis of this similarity in the molecular arrangements, the role of cinnamic acid, an achiral acid, is discussed, and the criteria for the choice of an achiral acid in the transformation of the racemic modification of an amine into a conglomerate crystal is proposed.
Asymmetric Radical Reaction in the Coordination Sphere. III. Asymmetric Addition of Trichloromethanesulfonyl Chloride and Carbon Tetrachloride to Olefins Catalyzed by a Ruthenium(II) Complex with Chiral Ligand
Authors: Kameyama Masayuki , Kamigata Nobumasa 
Published: July 2006

Abstract
The asymmetric addition of trichloromethanesulfonyl chloride to styrene in the presence of a catalytic amount of a ruthenium(II) complex with chiral ligands, Ru2Cl4[(−)-diop]3 or Ru2Cl4[(+)-diop]3, proceeds under mild conditions to give optically active 1:1 adducts, 1,1,1,3-tetrachloro-3-phenylpropane (2), with the extrusion of sulfur dioxide. When (−)-DIOP or (+)-DIOP was used as a chiral ligand of the ruthenium(II) complex, (R)-(+)-(2) or (S)-(−)-(2), was obtained with about 10% enantiomeric excess, respectively. A reaction mechanism involving a radical redox transfer mechanism was proposed; the asymmetric induction was attributed to the restricted configuration of the radical intermediates confined in the coordination sphere of the ruthenium complex with chiral ligands.
A Convenient One-Pot Cyanosilylation of Aldehydes and Ketones Using Potassium or Sodium Cyanide Impregnated on Amberlite XAD Resin and Trimethylsilyl Chloride
Authors: Sukata Kazuaki 
Published: July 2006

Abstract
In the cyanosilylation of benzaldehyde, the combination of potassium or sodium cyanide impregnated on Amberlite XAD resin and trimethylsilyl chloride has been found to be a good one-pot cyanosilylation agent. Although acetonitrile is the best solvent, substantial yields of the product is obtained even in a nonpolar solvent or without any solvent. In the reaction with other aldehydes or ketones, this method gives the corresponding silylated cyanohydrins in extremely high yields.
Polymer-Protected Metal Complex for Gas Separation. III. Water-Resistivity of Polystyrene Resin-Supported Aluminium Copper(I) Chloride as Solid Carbon Monoxide Adsorbent
Authors: Hirai Hidefumi , Hara Susumu , Komiyama Makoto 
Published: July 2006

Abstract
Solid adsorbents of carbon monoxide are prepared from aluminium chloride, copper(I) chloride, and a macroreticular type polystyrene resin by use of various solvents, and their resistivities against water vapor are investigated. The adsorbing capacities of the adsorbents prepared by use of carbon disulfide and dichloromethane remain virtually unchanged even after repeated (3–5 times) contacts of the adsorbents with nitrogen gas containing 10 mol% water with respect to the charged copper(I) chloride (water contents: 5600 and 4600 ppm). The adsorbents obtained with the use of benzene and toluene as preparation solvents, however, exhibit small but gradual decreases in the adsorbing capacities on the repeated contacts with nitrogen gas containing water. Scanning electron microscopy and energy dispersive X-ray microanalysis on the water-resistant adsorbents, prepared with the use of carbon disulfide and dichloromethane, show that the active species for the adsorption, aluminium copper(I) chloride, uniformly distributes in the beads of the polystyrene resin without formation of aggregates. Almost all of aluminium copper(I) chloride is located in the apolar microporosities of the polystyrene resin here, and is effectively protected from water vapor.
Energetics of the Sequential Electroreduction and Electrooxidation Steps of Benzenoid Hydrocarbons
Authors: Kubota Tanekazu , Kano Kenji , Uno Bunji , Konse Tomonori 
Published: July 2006

Abstract
The first and second reduction (E1⁄2.1red, E1⁄2.2red) and the first oxidation (E1⁄2.1oxd) standard potentials of benzenoid alternant hydrocarbons (BAH) were experimentally determined by means of cyclic voltammetry (CV) in nonaqueous solvents. The second standard oxidation potential (E1⁄2.2oxd) was however, estimated by checking the scan rate dependence of the irreversible CV curve. The equations pertinent to these potentials and their mutual relations were formulated from the points of view of the Born–Haber-type thermodynamic energy cycle and SCFMO calculations. Of the SCFMO calculations, the MO-paring property established in the PPP-type π-electron theory was very successful in the discussion of the equations given above. Under the acceptable assumptions that the solvation energies due to mono- and dications are put equal to those of the mono- and dianions respectively, and using the MO-pairing property, the equation of (E1⁄2.1oxd+E1⁄2.1red)=(E1⁄2.2oxd+E1⁄2.2red) was derived. The experimental results were well described by this equation. The solvationenergy values were evaluated by applying the experimentally determined reduction or oxidation potentials to the theoretical equations. An examination of the solvation energies has shown that these values can be interpreted by means of the Born-type equation.
Entropy Changes in the Inclusion Complex Formation of α-Cyclodextrin with Alcohols as Studied by the Titration Calorimetry
Authors: Fujiwara Hideaki , Arakawa Haruyuki , Murata Saburo , Sasaki Yoshio 
Published: July 2006

Abstract
The inclusion complex formation of α-cyclodextrin(α-CD) with various alcohols has been studied by means of titration calorimetry. The titration curve was analyzed successfully by the formation of a 1:1 hostguest complex, and the thermodynamic parameters were determined. The entropies of reaction are estimated from the statistical thermodynamics of molecules. However, the estimated values are found to deviate by an order of magnitude from the experimental ones. To resolve such a discrepancy, α-CD in solution is assumed to include a definite number(n) of water molecules which are replaced by a guest molecule with the progress of reaction. The entropies thus estimated depend extensively on the value of n, and a value of n is determined for each alcohol so that it reproduces just the experimental entropy. The resulting n values are nearly constant for various alcohols studied and are within a reasonable range expected from the data reported in crystal, supporting the model of interpretation.
Optical Resolution of Alcohols as Carbamates by HPLC on Cellulose Tris(phenylcarbamate) Derivatives
Authors: Okamoto Yoshio , Cao Zun-Kui , Aburatani Ryo , Hatada Koichi 
Published: July 2006

Abstract
The optical resolutions of various alcohols as phenylcarbamates were examined by HPLC on chiral stationary phases derived from sixteen cellulose tris(phenylcarbamate) derivatives. The optical resolving power of chiral stationary phases was greatly influenced by substituents on the phenyl groups of the cellulose derivatives. Also, cellulose tris(3,5-dimethylphenylcarbamate) could very efficiently resolve many racemic phenylcarbamates, including the carbamates of 2-butanol, 3-buten-2-ol, and 1-phenylethanol. Racemic phenylcarbamates having electron-donating substituents on the phenyl group were better resolved than those having electron-withdrawing substituents. The benzoates of most alcohlos were not resolved as efficiently as the carbamates.
New Synthetic Method of [2.2]Cyclophanes via Diselena[3.3]cyclophanes
Authors: Higuchi Hiroyuki , Tani Keita , Otsubo Tetsuo , Sakata Yoshiteru , Misumi Soichi 
Published: July 2006

Abstract
Syntheses of cyclic diselenides through diselenolates and the following deselenation reactions by means of three ways were studied. The preparation of the cyclic diselenides in the presence of excess sodium borohydride gave thirty-eight diselenides containing diselena[3.3]cyclophanes and alicyclic diseleno compounds in high yields in addition to two triple-bridged selenacyclophanes. Photodeselenation of the diselenides in tris(dimethylamino)phosphine afforded series of [2.2]cyclophanes in much higher yields than those of the other two methods, i.e. benzyne-Stevens rearrangement/Raney nickel hydrogenolysis and pyrolytic deselenation at ca. 650 °C. The present study demonstrates that the photodeselenation method, combined with the synthesis of their precursor diselenides, is much superior to the conventional dechalcogenation methods.
Synthesis and Electrocatalytic Properties of Rare Earth Platinum or Palladium Bronzes
Authors: Machida Ken-ichi , Enyo Michio , Adachi Gin-ya , Shiokawa Jiro 
Published: July 2006

Abstract
Dysprosium platinum and palladium bronzes, DyM3X4 (M=Pt or Pd; X=O, S, Se, or Te) were synthesized, except for DyPt3S4, by a solid state technique. They were found to have a high electric conductivity with ρ=0.3–2.6×10−5Ω cm and among them, the oxide bronzes crystallized in NaxPt3O4 type structure. The platinum oxide bronzes in particular showed a high activity for the methanol electrooxidation as compared with ordinary platinum electrodes.
Kinetic Studies on Dehydrogenation Reaction of 5,6-Dihydro-2,4(1H,3H)-pyrimidinediones in Aqueous Solution Induced by Argon Arc Plasma or Hydrogen–Oxygen Flame
Authors: Naraoka Hiroshi , Takasaki Michiaki , Nomoto Shinya , Harada Kaoru 
Published: July 2006

Abstract
5,6-Dihydro-2,4(1H,3H)-pyrimidinediones underwent dehydrogenation at the 5- and 6-position producing 2,4(1H,3H)-pyrimidinediones in aqueous solution induced by argon arc plasma or flames. From consideration based on the kinetic study of this reaction, it was found that abstraction of a hydrogen atom took place preferentially at the 6-position of the dihydropyrimidinediones.
[2π+2σ] and [4π+2σ] Type Cycloaddition Reactions of Furan and Benzofurans with Benzocyclopropene
Authors: Saito Katsuhiro , Ishihara Hiraku , Kagabu Shinzo 
Published: July 2006

Abstract
Reactions of benzocyclopropene with furan and benzofuran afforded [2π+2σ]-type cycloaddition products, where the furans act as 2π-components and benzocyclopropene acts as a 2σ-component. A similar reaction with 1,3-diphenylisobenzofuran gave a [4π+2σ]-type cycloaddition product using the furan as a 4π-component.
Modified Solubility Parameter as an Index to Correlate the Solubility in Supercritical Fluids
Authors: Ikushima Yutaka , Goto Tomio , Arai Masahiko 
Published: July 2006

Abstract
The conventional solubility parameter was modified so that it could be applied to supercritical fluids. It was found that the parameters could correlate the experimental solubility data of some hydrophobic solutes in carbon dioxide, ethylene, and carbon dioxide-entrainer systems.
Preparation and Structures of Acetylene Adducts of 4,6-O-Isopropylidene- and 4-O-Acetyl-6-O-triphenylmethyl-1,5-anhydro-2-deoxy-d-erythro-hex-1-en-3-uloses
Authors: Matsui Takanao , Morooka Takashi , Nakayama Mitsuru 
Published: July 2006

Abstract
Cyclobutene adducts were formed stereoselectively in good yields by the irradiation of acetone solutions of 4,6-O-isopropylidene- and 4-O-acetyl-6-O-triphenylmethyl-1,5-anhydro-2-deoxy-d-erythro-hex-1-en-3-uloses, derived from d-glucal triacetate, in the presence of acetylene. The stereochemistry at the ring junction was achieved by a single-crystal X-ray analysis and a chemical correlation with the derived compounds.
Kinetic Studies on the Oxidation of Thiols by Coenzyme PQQ
Authors: Itoh Shinobu , Kato Nobuyuki , Mure Minae , Ohshiro Yoshiki 
Published: July 2006

Abstract
Kinetic studies on the oxidation of thiols by coenzyme PQQ are carried out under anaerobic conditions. A bell shaped pH-rate profile having a maximum rate at around pKa of the thiol is observed. The rate-determining step changes between acidic and basic sides of the profile indicating the existence of at least one intermediate in the course of the reaction.
Monolayer Formation of Dilauroylphosphatidylcholine at the Polarized Nitrobenzene–Water Interface
Authors: Kakiuchi Takashi , Yamane Masataka , Osakai Toshiyuki , Senda Mitsugi 
Published: July 2006

Abstract
Double layer capacitance of the polarized nitrobenzene–water interface has been measured in the presence of the adsorption of l-α-dilauroylphosphatidylcholine (DLPC). The double layer capacitance was lowered with the increase of the DLPC concentration in the negative branch of the potential range where the aqueous phase was in negative potential with respect to the nitrobenzene phase. A saturated monolayer of DLPC was formed at a concentration of DLPC above 20 μmol dm−3. The area occupied by a DLPC molecule at the saturated monolayer was 0.73 nm2 which was estimated by comparing the capacitance data with those obtained from a spread monolayer of DLPC at the interface. In the negative branch the monolayer was stable over 100 mV of the applied potential across the monolayer. The adsorption was described by the Frumkin adsorption isotherm. The interaction between the adsorbed DLPC molecule was weak, corresponding to the penetration of nitrobenzene molecules and, possibly, ions between the hydrocarbon chains of DLPC. This penetration also explains the high capacitance value of 11 μF cm−2 for the saturation monolayer. In the potential range where the aqueous phase is positive, the capacitance increased with the DLPC concentration.
Application of the SPE Method to Organic Electrochemistry. VIII. The Incorporation of an Iron Redox Couple into Pt–Nafion and Its Behavior as a Mediator
Authors: Ogumi Zempachi , Mizoe Toshiyuki , Yoshida Naoki , Takehara Zen-ichiro 
Published: July 2006

Abstract
Fe2+ and Fe3+ were incorporated into Pt–Nafion. The full incorporation of Fe2+ into H+-type Nafion was attained beyond 0.3 M FeSO4. The ion-exchange selectivity of Fe2+ was estimated to about 2 to H+. The incorporated ions exhibited diffusional behavior inside the composite electrode. The formal potential of the incorporated iron(III/II) redox couple was dependent on both the H2SO4 and the Fe3+ and Fe2+ concentrations. The potential shift was, however, not so large as that reported on some redox systems on polymer-coated electrodes. The incorporated redox couple was revealed to behave as a mediator in the oxidation of l-ascorbic acid.
Equilibrium Studies on the Species Formed in the Extraction of Divalent Transition Metal Ions with 8-Quinolinethiol and Its 2-Methyl Derivative
Authors: Yuchi Akio , Sugiura Kiminari , Wada Hiroko , Nakagawa Genkichi 
Published: July 2006

Abstract
The equilibria were studied in the extraction of divalent transition metal ions (M2+: Co2+, Ni2+, Cu2+, Zn2+, Cd2+) with 8-quinolinethiol(Hqt) and its 2-methyl derivative (Hmqt). Precipitates form in the Cd–Hqt and Cu–Hmqt systems. In other systems except the Co–Hqt, ML2(L−: qt− or mqt−) is responsible for the extraction. Effects of anions and solvents were examined in the Zn–Hqt system. The Ni(qt)2, Ni(mqt)2, and Co(mqt)2 complexes hold the capacity to form the adduct with 1,10-phenanthroline. A mixture of diamagnetic Co(III) complexes is extracted in the Co–Hqt system. The main species was assigned as mer(S)-Co(qt)3 by the 13C NMR spectrum. The structures of other complexes are also discussed.
The Thermal Decomposition of Ammonium cyclo-Hexaphosphate (NH4)6P6O18·1.5H2O and Ammonium cyclo-Tetraphosphate (NH4)4P4O12
Authors: Takenaka Atsushi , Motooka Itaru , Nariai Hiroyuki 
Published: July 2006

Abstract
Ammonium cyclo-hexaphosphate 1.5-hydrate (NH4)6P6O18·1.5H2O was prepared. Under conditions similar to those in the thermal analysis (TG–DTA), the hydrate was heated in an electric furnace. The atmospheres used then were streams of humid air, dried air and dry ammonia gas. The products were characterized by the X-ray diffraction method and by HPLC-flow injection analysis (HPLC-FIA). The thermal decomposition of anhydrous ammonium cyclo-tetraphosphate (NH4)4P4O12 was also investigated. From each ammonium cyclo-phosphate, very analogous ammonium polyphosphate was produced. Its formation was considered to result from the polymerization of some lower-condenced phosphate radicals, which were generated on the cleavage of the ring anions of the cyclo-phosphates. The radicals incorporated water molecules in the atmosphere, which causes less formation of the ammonium polyphosphate and exhibited a TG gain and an exothermal DTA break. The exotherm could be attributed theoretically to the incorporation in case of the cyclo-tetraphosphate. Moreover, the release of ammonia from the starting material was supposed to be a trigger for the cleavage of the ring anions.
Effect of Ru3(CO)12 and Triisopropylphosphine on the Catalytic Activity of CO Hydrogenation by Co2(CO)8
Authors: Murata Kazuhisa , Matsuda Akio , Masuda Takashi , Ishino Masaru , Tamura Mitsuhisa 
Published: July 2006

Abstract
A catalyst system, containing Co2(CO)8 coupled with Ru3 (CO)12 and triisopropylphosphine((i-Pr)3P), was found to be effective for the ethylene glycol formation by homogeneous hydrogenation of CO: The most active catalyst, the activity of glycol formation of which was ca. 3 times higher than that of Co2(CO)8 alone, was obtained at phosphorus: Co: Ru ratio of 2 : 1 : 1.
Interaction between Copper(I) Chloride and Active Carbon in Active Carbon-Supported Copper(I) Chloride as Solid Carbon Monoxide Adsorbent
Authors: Hirai Hidefumi , Wada Keiichiro , Komiyama Makoto 
Published: July 2006

Abstract
Magnetic susceptibility (−4.7×10−9 m3 kg−1) of the carbon monoxide adsorbent prepared from 10.0 g of active carbon and 1.4 g of copper(I) chloride is in paramagnetic side with respect to the value (−10.1×10−9 m3 kg−1) estimated from the susceptibilities of the components. Almost all the copper atoms are in their monovalent states, as shown by X-ray photoelectron spectroscopy. These results have indicated specific interaction between active carbon and copper(I) chloride in the adsorbent.