bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidation of Cyclopentene by RuCl3–NaOCl Catalyst
Authors: Orita Hideo , Hayakawa Takashi , Takehira Katsuomi 
Published: July 2006

Abstract
Oxidation of cyclopentene by RuCl3–NaOCl catalyst in an aqueous-organic two phase system was investigated by changing compositions of solvent system and additives to the aqueous solution. Use of acetonitrile as a cosolvent enhanced the reaction rate greatly, and addition of NaOH improved the yield of glutaric acid up to 80%.
S–Alkyl-4-oxothianium Ions for the Synthesis of Cyclopentenones. Acid-Catalyzed Cyclization of Divinyl Ketones
Authors: Matsuyama Haruo , Takei Yuji , Kobayashi Michio 
Published: July 2006

Abstract
A new approach to 2-cyclopentenones via an acidic cyclization of divinyl ketones by the use of S–alkyl-4-oxothianium ions as key compounds is described.
Stereoselective Reduction of Symmetrical Diketones with Biological Methods. Microbial Reduction of cis-2,7-Decalindione
Authors: Chikamatsu Hiroaki , Taniguchi Masatoshi , Kanemitsu Takamasa 
Published: July 2006

Abstract
The pro-S group of two enantiotopic carbonyl groups in cis-2,7-decalindione was preferentially reduced with Rhodotorula rubra to give (−)-(7S,9R,10S)-7-hydroxy-cis-2-decalone of high optical purity.
Tertiary Amine-Catalyzed Acyl Group-Exchange Reactions of N, O-Diacyl-o-aminophenols
Authors: Sakurai Tadamitsu , Yamada Shuichi , Inoue Hiroyasu 
Published: July 2006

Abstract
A kinetic study on the base-catalyzed acyl group-exchange reactions of N,O-diacyl-o-aminophenols was undertaken to show that the formation of the amidate ion should be the rate-determining step in these intramolecular acyl-exchange reactions, and that the electron-withdrawing power of acyl group becomes an important factor to control the relative stabilities of a pair of N,O-diacyl-o-aminophenols.
Dehydrogenation of Ethylbenzene on Potassium-Promoted Iron Oxide Catalyst Containing Magnesium Oxide
Authors: Hirano Takenori 
Published: July 2006

Abstract
Among potassium-promoted iron oxide catalysts containing a minor chromia and a series of alkaline earth oxides, i.e., MgO, CaO, SrO, and BaO, the MgO-containing catalyst showed the best performance with respect to the dehydrogenation activity and the stability even at a steam-toethylbenzene molar ratio (H2O/EB ratio) as low as 6.
Basis Set Dependency of Molecular Electronic Structures
Authors: Ichikawa Hiroshi , Sameshima Keiichiro , Ebisawa Yukiko 
Published: July 2006

Abstract
The total atomic charges as well as the kinetic and potential energies calculated using 22 different basis sets were compared. It was shown that polarization functions must be added to atoms of the first row as well as the hydrogen atom in order to obtain well-balanced wave functions. The STO-NG (N=3, 4, 5, or 6) method, which is considered to give poor wave functions, is shown to give well-balanced wave functions.
Photochemical Reactions of Bromoanthraquinones in Ethanol at Room Temperature Studied by Steady-State Photolysis and Laser Photolysis
Authors: Hamanoue Kumao , Nakayama Toshihiro , Sawada Kazuhide , Yamamoto Yoshiaki , Hirase Susumu , Teranishi Hiroshi 
Published: July 2006

Abstract
Photolyses of α-bromoanthraquinones (1-bromo-, 1,5-dibromo-, and 1,8-dibromoanthraquinones) with 366-nm light in ethanol at room temperature gave rise to the formation of debrominated 9,10-anthracenediol as a final product. This was interpreted in terms of the sequence of the formation of α-bromo-9,10-anthracenediols followed by the photochemical dehydrobromination yielding the corresponding anthraquinones with one less bromine atom than original ones. Photolysis of 2-bromoanthraquinone gave rise to the formation of 2-bromo-9,10-anthracenediol, and no dehydrobromination was observed. Combined with the values of the quantum yields of photoreduction, the results of the laser photolyses revealed that the rate constant for the hydrogen-atom abstraction from ethanol decreased as an increase of the ππ* character of the lowest triplet states of α-bromoanthraquinones.
Nuclear Magnetic Resonance Studies of Copper(I) Complexes of Imidazoles. II. Their Reaction with Ethylene, Phosphite, and Isocyanides
Authors: Kitagawa Susumu , Munakata Megumu 
Published: July 2006

Abstract
The reaction of binary copper(I) complexes of monodentate imidazole(im) with π acceptor ligands (ethylene, triethyl phosphite, p-tolyl isocyanide, and phenyl isocyanide) have been carried out in acetone. The resultant copper(I) complexes have been characterized by 1H and 31P NMR spectroscopy. Ethylene reacts with [Cu(im)2]+ (2) to give [Cu(im)2(C2H4)]+ (2-b), but does not react with [Cu(im)3]+ (3). This shows a clear difference in reactivity between 2 and 3. Phosphite and isocyanides give rise to a substitution reaction for im in 2 and 3, accompanying with addition reaction. Among the copper(I) compounds prepared here, two- and fourcoordinate forms show sharp 1H NMR signals of coordinated im, indicating that they are in the slowexchange regime. This proved that 1H NMR spectroscopy is a useful tool to characterize diamagnetic copper(I)–imidazole complexes in solution.
Splitting Parameters in Ligand Field Absorption Bands of Cobalt(III) Ammine Complexes with Chloro or Aqua Ligands
Authors: Mitsutsuka Yoshihiro , Kondo Ichiji , Nakahara Masayoshi 
Published: July 2006

Abstract
The splitting parameters of ligand field absorption bands for cobalt(III) ammine complexes containing aqua or chloro ligands were investigated by microspectrophotometry. The polarized absorption spectra were measured for these crystals. The spectra obtained were separated into Gaussian components according to a nonlinear least-squares method. The splitting parameters were determined from the locations of the components for the first absorption band.
The Solvent-Extraction Equilibrium of Vanadium(III, IV, V) with Acetylacetone in Nonpolar Solvents
Authors: Imura Hisanori , Suzuki Nobuo 
Published: July 2006

Abstract
The extraction of vanadium(III, IV, V) with 0.01–0.1 mol dm−3 acetylacetone in such nonpolar organic solvents as heptane, benzene, and chloroform has been investigated at pH 1–7 under a nitrogen atmosphere. The extraction constant, the partition coefficient, and the stability constant for the vanadium(III) and vanadium(IV) chelate were determined. Vanadium(V) was found to have been extracted as the vanadium(IV) chelate with reduction.
A Voltammetric Detection System for Measuring the Concentration of Chloride Ions in Fresh Concrete
Authors: Yamada Akifumi , Hodouchi Kazunori , Katoh Koichi , Otsuga Nozomu , Hashida Choichi , Honda Tetsuo 
Published: July 2006

Abstract
A voltammetric detection system for measuring the concentration of chloride ions in fresh concrete has been developed. A comparative determination using the Volhard titration method showed that the voltammetric system works as well in slushy concrete as in an aqueous chloride solution. No interference from the admixture was observed.
Mössbauer and DTA Studies of K2SO4–ZnSO4–Fe2(SO4)3 Glasses
Authors: Nishida Tetsuaki , Takashima Yoshimasa 
Published: July 2006

Abstract
A structural study of ternary sulfate glasses has been performed to elucidate the nature of the chemical bond and the local structure of these glasses. Mössbauer parameters (isomer shift and quadrupole splitting) show drastic decrease with an increase in the K2SO4 content. This is ascribed to the gradual change in the coordination number of iron (Fe3+) from six (Oh) to four (Td) when the K2SO4 content is higher than about 60 mol%. Lattice dynamic information obtained from low-temperature Mössbauer measurements suggests that the chemical bond between the iron and the neighboring oxygen is essentially ionic. All the Mössbauer results for the ternary sulfate glasses suggest that the Fe3+ ions are present at the vacant sites (voids) of the pseudospherical SO42− ions which are considered to be randomly packed to constitute the ionic glasses. Glass transition temperature (Tg) of these sulfate glasses, obtained from DTA measurements, also shows a gradual decrease with increasing K2SO4 content. This result is very similar to the composition dependency of the Mössbauer parameters described above, and suggests that the ionic field strength of the sulfate glasses decreases with increasing K2SO4 content. These experimental results are ascribed to the increased intermolecular bond length between the pseudospherical SO42− units.
Photochemical Reactions of Aryltriethylgermanes and Diethyldiphenylgermane
Authors: Kobayashi Michio , Kobayashi Masanori 
Published: July 2006

Abstract
Aryltriethylgermanes and diethyldiphenylgermane were found to split easily to generate germyl radicals by irradiation with a medium-pressure mercury lamp in hexane or cyclohexane. The germyl free radicals produced reacted with hydrocarbon radicals generated from the solvent by hydrogen abstraction either by recombination or by disproportionation.
Preparation and Thermal Ring Opening of 1-(Methylthio)cyclopropenes
Authors: Yoshida Hiroshi , Sano Hiroe , Kato Makoto , Ogata Tsuyoshi , Matsumoto Kiyoshi 
Published: July 2006

Abstract
The reaction of (methylthio)diphenyl- and methyl(methylthio)phenylcyclopropenium salts with Grignard reagents (methyl, 1-methylethyl, and phenyl) yielded 1-(methylthio)cyclopropenes as major products together with isomeric 3-methylthio-1-cyclopropenes in moderate total yields. Phenyllithium also reacted similarly with the salt to afford cyclopropenes in lower yields. Thermal ring opening of 1-(methylthio)cyclopropenes took place readily at room temperature or on heating at around 80 °C to give indene and/or butadiene derivatives in good yields. Product analysis of the reaction in methanol as well as kinetic studies of one of 1-(methylthio)cyclopropenes gave strong evidence for the intermediacy of vinylcarbene in the ring opening of cyclopropene.
Syntheses, Characterization, and Structures of (Monomethyl Carbonato)–Nickel(II), –Copper(II), and –Cobalt(II) Complexes with Tetraazacycloalkanes Obtained from CO2 Uptake
Authors: Kato Masako , Ito Tasuku 
Published: July 2006

Abstract
A new series of monomethyl carbonato complexes of nickel(II), cobalt(II), and copper(II) containing tetraazacycloalkanes (L) have been synthesized and characterized: Ni(L)(O2COCH3)(ClO4) (L=[14]aneN4 (1); L=[15]aneN4 (2); L=iso-[14]aneN4 (3); L=RSRS-Me4[14]aneN4 (4)), [Ni(RRSS-Me4[14]aneN4)(O2COCH3)2]·HNEt3ClO4 (5), Cu([14]aneN4)(O2COCH3)(ClO4) (6), [Cu(Me4[14]aneN4)(O2COCH3)](ClO4)·CH3OH (7), and Co(L)(O2COCH3)(ClO4) (L=[15]aneN4 (8); L=Me4[14]aneN4 (9)), where [14]aneN4=1,4,8,11-tetraazacyclotetradecane, [15]aneN4=1,4,8,12-tetraazacyclopentadecane, iso-[14]aneN4=1,4,7,11-tetraazacyclotetradecane, Me4[14]aneN4=1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane, RSRS-=1RS,4SR,8RS,11SR-, and RRSS-=1RS,4RS,8SR,11SR-. These compounds have been obtained through CO2 uptake reaction in basic methanol from the corresponding four-coordinate complex, [M(L)](ClO4)2. X-Ray structures of three compounds, 4, 5, and 6, have been determined. Compound 4 is a five-coordinate complex with the trigonal bipyramidal geometry (Type II), in which CH3OCO2− is coordinated in a unidentate fashion. Compound 5 is a tetragonally distorted sixcoordinate complex with two unidentate CH3OCO2− at axial sites (Type III). Compound 6 is also a tetragonally distorted six-coordinate complex but the CH3OCO2− ligand bridges two neighboring [Cu([14]aneN4)]2+ to form a linear chain structure (Type I). All the monomethyl carbonato complexes synthesized are classified into these three types on the basis of IR and/or electronic spectral data, supplemented with the X-ray results. Efficiency of the CO2 uptake depends strongly on the coordination structure which is controlled by a combination of metal ion and tetraazacycloalkane. Differences in reactivity among the complexes of various metal ions and factors influencing the efficiency have been discussed in connection with the zinc(II) system which undergoes the most effective CO2 uptake of this type.
Effect of the Structure of Insoluble Pyridinium-Type Polymer on Its Ability to Capture Bacteria in Water
Authors: Kawabata Nariyoshi , Hayashi Takaya , Nishikawa Masaru 
Published: July 2006

Abstract
Effect of the structure of insoluble pyridinium-type polymer on its ability to capture bacteria in water was investigated. Strong ability of the polymer was further confirmed by an equilibrium capture experiment. The ability was quantitatively evaluated by the removal coefficient reported previously based on initial rate of decrease of viable cell counts caused by the presence of the polymer. The coefficient uniformly increased with the content of pyridinium group, and considerably increased when the content of divinylbenzene became smaller. The coefficient also increased with the content of 4-vinylpyridine in the polymer matrix. Based on these observations, presence of pyridinium group was concluded to be essentially important in the affinity of the polymer for bacterial cells. Hydrophilicity and high degree of swelling in water of the polymer matrix appeared to enhance the ability to capture bacteria.
Optical Resolution of erythro-2-Amino-1,2-diphenylethanol by Reciprocal Crystallization of the Diastereomeric Salts with (−)-Mandelic Acid on Alternate Seeding
Authors: Saigo Kazuhiko , Sugiura Izuru , Shida Ikuko , Tachibana Kouzou , Hasegawa Masaki 
Published: July 2006

Abstract
erythro-2-Amino-1,2-diphenylethanol was efficiently resolved into a pair of enantiomers by reciprocal crystallization of the diastereomeric salts with (−)-mandelic acid on alternate seeding.
Resonance Raman Spectra of Red-Shifted Retinal Schiff’s Base
Authors: Sugihara Toshiharu , Kitagawa Teizo 
Published: July 2006

Abstract
We have found that the visible absorption maximum (λmax) of retinal Schiff’s base in fluoro alcohols is considerably red-shifted. The C=N stretching Raman line exhibits a frequency shift in deuterated fluoro alcohols, indicating that the Schiff’s base is protonated. Frequencies of the in-phase C=C stretching Raman lines (νC=C) changed linearly with λmax, and the νC=C vs. λmax correlation coincides with that observed for retinoid proteins.
Tetraoxotetraazaparacyclophanes with Various Alkyl Chains as Hosts for Hydrophobic Compounds
Authors: Kodaka Masato , Fukaya Toshio 
Published: July 2006

Abstract
Tetraoxotetraazaparacyclophanes with short or long alkyl chains and tertiary amino groups were synthesized. It was shown that NN′N″N'″-tetrakis-(3-dimethylaminopropyl)-3,10,21,28-tetraoxo-2,11,20,29-tetra-aza[3.3.3.3]paracyclophane and NN′N″N'″-tetrakis-(5-dirnethylaminopentyl)-3,10,21,28-tetraoxo-2,11,20,29-tetra-aza[3.3.3.3]paracyclophane as well as NN′N″N'″-tetrakis-(10-dimethylaminodecyl)-3,10,21,28-tetraoxo-2,11,20,29-tetra-aza[3.3.3.3]paracyclophane could undergo a complex formation with picrate and 8-anilino-1-naphthalenesulfonic acid, while the dissociation constants for the former cyclophanes were larger than those for the latter cyclophane. The hydrolysis of p-nitrophenyl hexanoate was also studied in the presence of the cyclophanes and azide ion (N3−), but the reaction was not significantly activated.
Selective 2′-O-Methylation of Pyrimidine-Ribonucleosides by Trimethylsulfonium Hydroxide in the Presence of Mg2+ and Ca2+ Ions
Authors: Yamauchi Kiyoshi , Nakagima Toru , Kinoshita Masayoshi 
Published: July 2006

Abstract
Reactions of various ribonucleosides with trimethylsulfonium hydroxide were investigated in the presence of Mg2+ and Ca2+ ions. The 2′-OH groups of pyrimidine-ribonucleosides were methylated selectively.
The Addition of Alcohol to 1,2-Naphthoquinone Promoted by Metal Ions. A Facile Synthesis of 4-Alkoxy-1,2-naphthoquinones
Authors: Takuwa Akio , Soga Osamu , Iwamoto Hidetoshi , Maruyama Kazuhiro 
Published: July 2006

Abstract
In the presence of some metal ions and sodium iodate, 1,2-naphthoquinone (1) readily reacted with methanol to give 4-methoxy- 1,2-naphthoquinone (2a). The activity of the metal ions increased in the following order: Co(II)&lt;Ni(II) &lt;&lt; Cu(II)&lt;La(III) &lt;&lt; Ce(III). The reaction was remarkably affected by the reaction temperature, reaction time, and molar ratio of the chelating agent. By the use of 1 equivalent of cerium salt to 1, the yield of 2a increased to 81% at 20 °C for 30 min. In higher alcohols, the addition reaction proceeded under similar conditions to give 4-alkoxy-1,2-naphthoquinones (2b–f) in 46–75% yields.
The Enantioselective Hydrogenation of Methyl Levulinate on the Interactive and Noninteractive Sites of Nickel Surfaces with Preadsorbed Asymmetric Compounds
Authors: Yokozeki Michio , Shimokoshi Kazuo , Miyazaki Eizo 
Published: July 2006

Abstract
The gaseous hydrogenation of methyl levulinate on the Ni surface modified with the optically active tartaric, malic and lactic acids was studied. It was found that γ-valerolactone is formed on an unmodified surface, while optically active methyl 4-hydroxypentanoate [MHP] and γ-valelolactone [VL] are formed consecutively on modified surfaces. Using these results and the temperature dependency of the reaction rates, along with previous theoretical results [J. Phys. Chem., 89, 2397 (1985)], it was concluded that, on an Ni surface modified with preadsorbed optically active acids, there are two different and independently operative sites, i.e., noninteractive (nonselective) and interactive (selective) sites which give the enantioselectivity. Further, the fractions of the noninteractive sites in the total amount of active sites were estimated to be about 18 and 13% for TA- and MA-modified surfaces respectively. A similar character of the active sites was found for the enantioselective hydrogenation of methyl acetoacetate [MAA] to methyl 3-hydroxybutyrate [MHB] on TA-modified Ni, where the fraction of noninteractive sites was evaluated to be about 15%.
Effects of Cyclodextrins on the Fluorescence of Diphenyl Phosphate in Aqueous Solution
Authors: Hamai Sanyo 
Published: July 2006

Abstract
The effects of α-, β-, and γ-cyclodextrin (CD) on intramolecular excimer formation between the two phenyl groups of diphenyl phosphate (DP) in aqueous solution were investigated by means of absorption and fluorescence spectra. It was found that DP forms 1 : 1 inclusion compounds with α-, β-, and γ-CDs. In the inclusion compound with α- or β-CD, only one phenyl group of a DP molecule is incorporated in the cavity of a CD molecule. In the case of γ-CD, however, the cavity can accommodate either one or two phenyl groups of a DP molecule. The pH dependence of the equilibrium constant for the formation of the inclusion compound between DP and β-CD has also been examined. Over the pH range from 3.46 to ≈10 the equilibrium constant does not change, whereas for pH values above ≈11 it decreases drastically.
Heterogeneous Hydration of Acrylonitrile over the Metal Oxide Catalysts in Liquid Phase
Authors: Sugiyama Kazuo , Miura Hiroshi , Nakano Yasushi , Sekiwa Hideyuki , Matsuda Tsuneo 
Published: July 2006

Abstract
The liquid-phase hydration of acrylonitrile has been examined over various single metal oxide catalysts at 65 °C. Numerous metal oxides have proved to be active for hydration and have been used to produce three products: acrylamide, ethylene cyanohydrin, and bis(2-cyanoethyl) ether. These oxide catalysts could be divided into two groups with respect to the acrylamide selectivity with 100% or not. A good relationship between the catalytic abilities (activity and selectivity) and the solid acid-base properties of each metal oxide group examined in benzene or in water was observed. Differences in the hydration selectivity to either a C≡N or a C=C bond of acrylonitrile over the catalysts could be explained on the basis of the IR spectra of two adsorbed states of acrylonitrile on the metal oxide surface. It was proved that the liquid-phase hydration of acrylonitrile over the insoluble metal oxide catalysts was an acid-base-catalyzed reaction proceeding on the acidic or basic surface hydroxyl groups.
Polarized Raman and Infrared Spectra of [1H4]- and [2H4]Pyridazines
Authors: Ozono Yoshimi , Nibu Yoshinori , Shimada Hiroko , Shimada Ryoichi 
Published: July 2006

Abstract
The polarized Raman and infrared spectra of [1H4]- and [2H4]pyridazines were studied. Assignments of the normal vibrations made by previous workers were reexamined on the basis of polarization behavior of the Raman and infrared bands and also through the normal coordinate calculation, and reasonable assignments are presented.
Synergistic Extraction of Copper(II) and Zinc(II) with Tributyl Phosphate and Crown Ether
Authors: Hasegawa Yuko , Miyata Hirofumi , Yoshida Satoshi 
Published: July 2006

Abstract
The solvent extraction of copper(II) and zinc(II) with 12-crown-4 (12C4) or 15-crown-5 (15C5) as picrates into chloroform containing tributyl phosphate (TBP) has been studied. The following conclusions have been reached. i) Even in the presence of TBP which is more basic than crown ether, either copper(II) or zinc(II) is extracted in association with 2 moles of 12C4 or 15C5. ii) The crown ether complex of either copper(II) or zinc(II) forms 1 : 1 : 1 (metal(II): crown ether: TBP) stoichiometric adducts in chloroform. iii) The 12C4 complex of either copper(II) or zinc(II) forms more stable adducts with TBP than the 15C5 complex. iv) The extraction of the metal (II) with 15C5 and TBP is better than that of 12C4 and TBP. v) The copper(II) complex with 12C4 or 15C5 forms more stable TBP adducts than those from zinc(II) complex.
Effects of EDTA Derivatives on the Photoreduction of Methyl Viologen by a Thiacarbocyanine Sensitizer in a Micellar Solution
Authors: Nakagaki Masayuki , Komatsu Hiroaki , Tanaka Hiromi , Handa Tetsurou 
Published: July 2006

Abstract
The photoinduced reduction of Methyl Viologen (MV2+) by ethylenediaminetetraacetate (EDTA), 1,2-propanediamine-N,N,N′,N′-tetraacetate (MeEDTA), and trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetate (CyDTA) was investigated by using 3,3′-dioctadecylthiacarbocyanine (C18–18+) as a sensitizer in a micellar solution of a nonionic surfactant, heptaethylene glycol monododecyl ether. The production rate of reduced Methyl Viologen (MV+·) decreased with the light-irradiation time, while the deceleration increased in the order of: CyDTA&lt;MeEDTA&lt;EDTA. The concentration of the EDTA derivatives at the micellar surface was estimated to be in the order of EDTA&lt;MeEDTA&lt;CyDTA, this difference in the concentration being attributed to such hydrophobic groups as methyl group and cyclohexane ring in the EDTA-derivative molecules. The high concentration of the EDTA derivatives at the surface accelerated the reaction of the sensitizer divalent cation radical (C18–182+·) with the EDTA derivatives, prevented the consumption of MV+· through the back reaction of C18–182+· with MV+·, and facilitated the efficient photoproduction of MV+·. It was demonstrated that the hydrophobic interaction between the EDTA-derivative molecules and the micellar surface is an important factor in determining the efficiency of the photoinduced MV+· production.
Polymerization of Styrene Adsolubilized in Surfactant Adsorbed Bilayer on Pigments
Authors: Meguro Kenjiro , Yabe Toshikazu , Ishioka Sayuri , Kato Kazufumi , Esumi Kunio 
Published: July 2006

Abstract
The polymerization of styrene adsolubilized in a surfactant-adsorbed bilayer formed on the surface of inorganic pigments (iron oxide, titanium dioxide) was attempted in order to modify their surface properties. After the polymerization, the amount of polystyrene formed on the pigments gradually increased with an increase in the amount of styrene adsolubilized. Further, the molecular weight of the polystyrene formed changed with an increase in the amount of styrene. The surface properties of pigments after the polymerization were characterized by FTIR-PAS, turbidity, and zeta potential measurements.