bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photo-induced Polar Addition of Protic Solvents to Cycloalkenones. Evidence for the Ground-state trans Isomers as Chemically-reactive Intermediates
Authors: Noyori Ryoji , Katô Masao 
Published: July 2006

Abstract
The photo-induced reaction of cyclic α,β-unsaturated ketones with protic media is described. The irradiation of 2-cycloheptenone or 2-cyclooctenone in various protic solvents (alcohols, acetic acid, water, and diethylamine) results in the formation of Michael-type solvent adducts. The chemically-reactive species have been demonstrated to be the highly strained trans isomers in a ground state. The irradiation of cis-2-cyclononenone affords the stable trans isomer, which reacts in the dark with methyl alcohol at an elevated temperature to give 3-methoxycyclononanone. The irradiation of 2-cyclohexenone in methyl alcohol yields 3-methoxycyclohexanone in a poor yield. The possible existence of trans-2-cyclohexenone is discussed.
Aromatic Bromination and Iodination with Mixtures of Antimony (V) Chloride and Halogens
Authors: Uemura Sakae , Onoe Akira , Okano Masaya 
Published: July 2006

Abstract
Equimolar mixtures of SbCl5 and Br2 or I2 were found to be elegant reagents for the halogenation of certain aromatic substrates. In carbon tetrachloride, halogenobenzenes afforded the corresponding bromo- and iododerivatives with high para-selectivities (more than 95%) in good yields. The bromination of aromatic compounds with deactivating groups, such as ethyl benzoate and nitrobenzene, was simply achieved in 1,2-dichloroethane. Based on competitive halogenation data, the attack of BrCl or ICl (both formed in situ) on aromatics has been suggested.
The Reaction of Sulfinic Acids with N,N-Dimethylaniline
Authors: Oae Shigeru , Yamada Osamu , Maeda Tetsuya 
Published: July 2006

Abstract
When N,N-dimethylaniline was allowed to react with p-toluenesulfnic acid, unusual demethylation products, i.e., p-(N,N-dimethylamino)benzyl p-tolyl sulfone and p-(N-methylamino)benzyl p-toly sulfone were obtained. N-p-Toluenesulfonylmethyl-N-methylaniline was proposed to be a discrete intermediate, which undergoes intermolecular rearrangement in the presence of acid eventually to afford the above products. Similar results were obtained for the reaction of N-methylaniline with p-toluenesulfinic acid.
Optically Active Triptycenes. VII. Synthesis, Optical Resolution and Absolute Configuration of 3-Chloro and 4-Chloro-7-substituted Triptycenes.
Authors: Hashimoto Michiaki , Shimizu Yasumi , Ogura Fumio , Nakagawa Masazumi 
Published: July 2006

Abstract
Isomeric 3- or 4-chlorotriptycene-7-carboxylic acid was synthesized from sodium anthraquinone-β-sulfonate and resolved with quinidine methohydroxide. The absolute configurations of (−)-3-chloro- and (−)-4-chlorotriptycene-7-carboxylic acids could be determined to be 1S,6S and 1S,6R, respectively, by the chemical correlation with (+)-2,5-dimethoxy-8-chlorotriptycene whose absolute configuration was proved to be 1R,6S by X-ray and chemical means.
A Convenient Method for the Preparation of Ketones by the Reaction of Grignard Reagents with Carboxylic Acid Derivatives
Authors: Araki Masashi , Sakata Shigeru , Takei Hisashi , Mukaiyama Teruaki 
Published: July 2006

Abstract
It was found that ketones were prepared in excellent yields by the reaction of Grignard reagents with S-(2-pyridyl) thioates and their analogues or with 2-pyridyl esters. The mechanism of this reaction was also discussed. This useful method for the preparation of ketones was successfully applied to the syntheses of cis-jasmone and dihydrojasmone.
The Crystal and Molecular Structure of Bicyclomycin, a New Antibiotic
Authors: Tokuma Yoji , Koda Shigetaka , Miyoshi Toshio , Morimoto Yukiyoshi 
Published: July 2006

Abstract
The molecular structure of a new antibiotic, Bicyclomycin (C12H18O7N2), has been elucidated by X-ray diffraction analysis. Bicyclomycin crystallizes from aqueous solution in two forms, an orthorhombic and a monoclinic systems. The crystal data for the former are a=11.72, b=12.72, c=8.80 Å and the space group P212121, while those for the latter are a=10.27, b=10.91, c=6.67 Å, β=101.4°, and the space group P21 The crystal structure of the former was solved by the direct method and refined by least-squares method to a final R factor of 0.07 for 1623 reflections. The established structure is
(Remark: Graphics omitted.)
The diketopiperazine ring is folded into a boat form. The conformations of the side chain are all gauche or nearly so. All the oxygen and nitrogen atoms participate in two intramolecular and four intermolecular hydrogen bonds.
Calculation of the Widths for Isotropic Parts of Highly-polarized Raman Lines: Vibrational Relaxation of Infrared-inactive Levels
Authors: Kakimoto Masao , Fujiyama Tsunetake 
Published: July 2006

Abstract
A theoretical calculation is made to explain the widths of the isotropic parts of polarized Raman lines in liquids. The calculation is based on the model of the intermolecular resonance-type vibrational relaxation through the vibration-dependent term of the Lennard-Jones atom-atom interaction. The result is applied to the Raman lines of liquid nitrogen, oxygen, and carbon disulfide, and compared with the experimental data.
Electrical Properties of Evaporated Thin Films of Copper Phthalocyanine
Authors: Sakai Yoshiro , Sadaoka Yoshihiko , Yokouchi Hirofumi 
Published: July 2006

Abstract
The electrical properties of evaporated thin films of copper phthalocyanine (CuPc) were investigated by the ac method. The frequency dependence of conductivity and capacitance, and the activation energy for dc conductivity in α- and β-CuPc were determined. No significant variation in the electrical properties was observed with the difference in the phases of CuPc films in vacuo. The frequency dependence of conductivity and capacitance can be explained in terms of the simultaneous hopping and band conduction, viz., σ=σdc+A1·ωn and C=C+A2·ω1−n. The energy gap for α- and β-CuPc in vacuo is 1.80 eV and 1.89 eV, respectively. The adsorbed O2 gas has a great effect on the dc conductivity but little on the ac conductivity of α-CuPc film. The adsorption of oxygen on α-phase GuPc might be the cause of high dc conductivity and low activation energy(0.5–0.7 eV) as compared with those in vacuo.
Ligand-Ligand Interaction in the β-Diketonato Complexes of Be2+, Al3+, and Zn2+
Authors: Ohno Takeshi , Kato Shunji 
Published: July 2006

Abstract
The fluorescence yield (ΦF) and the phosphorescence yield (ΦP) of acetylacetone, benzoylacetone, and dibenzoylmethane were enhanced by coordination of Zn2+, Al3+, and Be2+ in an increasing order. In the bis- and the tris-bidentate complexes, not only did the ratios of ΦP to ΦF increase, but also the lifetimes of the phosphorescences became a little longer than that of the corresponding mono-bidentate complex. This change originates from some kinds of interaction between the ligands in the excited and ground states. Such an inter-ligand interaction was supported by the measurement of the polarization. However, the interaction energy is smaller than the expected values in the analyses of the absorption spectra and the circular dichroism in the region of the ligand band. A difference in the absorption spectra between the mono- and the bis- or the tris-bidentate complexes was seen only in the Franck-Condon factors; this finding supports the extension of the excited state through the two or the three ligands due to the weak inter-ligand interaction.
The Mechanism of the Hydrolysis of Condensed Phosphates. I. The Solvent Effect on the Hydrolysis of Pyro- and Tripolyphosphates
Authors: Watanabe Makoto 
Published: July 2006

Abstract
The hydrolysis of pyro- and tripolyphosphates was run in formic acid–water, acetic acid–water, dioxane–water, and water solvents with an initial concentration of 0.025 mol/l. The hydrolysis of both the phosphates followed first-order kinetics with respect to the concentration of the phosphate under all the conditions studied. The rate of the hydrolysis of both the phosphates in the formic acid–water and acetic acid–water solvents is slower, and that in dioxane–water solvent is faster, than in water. From the results, it has been concluded that, in the formic acid–water and acetic acid–water solvents, the nucleophilicity of the water molecule may decrease on account of the hydrogen bond of the water molecule with these acids, while, in the dioxane–water solvent, since the scission of the hydrogen bond between water molecules may occur by the interaction of the dioxane and the water molecules, the nucleophilicity of the water molecule may increase. The activation energy of the hydrolysis of the phosphates was 19–28 kcal/mol and increased with an increase in the pH value of a solution. The hydrolysis of pyro- and tripolyphosphates has been concluded to be a SN2 reaction; the rate-determining step may be the nucleophilic attack of a water molecule on the phosphorus atom of the phosphates.
Mechanism of Charge-transfer Polymerization. X. Flash Photolysis of the N-Vinylcarbazole–Pyromellitic Dianhydride System
Authors: Shirota Yasuhiko , Tomikawa Tamotsu , Nogami Takashi , Tada Kazuhiro , Yamamoto Naoto , Tsubomura Hiroshi , Mikawa Hiroshi 
Published: July 2006

Abstract
The formation of transient N-vinylcarbazole cation-radical and pyromellitic dianhydride anion-radical was demonstrated for the N-vinylcarbazole-pyromellitic dianhydride-solvent system by means of flash spectroscopy. The transient decay process was found to be solvent-dependent. In 1,2-dichloroethane the decay of the anion-radical was of the first-order at initial stage (t&lt;100 μs), and the second-order kinetics (t&lt;100 μs) then followed. In acetonitrile the transient decay followed the second-order kinetics in the whole time region.
An X-Ray Diffraction Study of the Structure of Hydrated Copper(II) Ion in a Copper(II) Perchlorate Solution
Authors: Ohtaki Hitoshi , Maeda Masunobu 
Published: July 2006

Abstract
The structure of hydrated copper(II) ion was determined by means of the X-ray diffraction of a 3.55 M copper(II) perchlorate solution. The radial distribution curve showed that the copper(II) ion has a distorted octahedral structure with six water molecules. Four water molecules occupy the equatorial sites of the octahedron at a distance of 1.94±0.02 Å from the Cu(II) ion and the other two water molecules at the axial sites are 2.43±0.03 Å distant from the central ion.
Mössbauer Spectroscopic Studies of Iron(II) and Iron(III) 1-Nitroso-2-naphtholate Complexes
Authors: Takada Mitsuko , Sano Hirotoshi 
Published: July 2006

Abstract
The anomalous Mössbauer parameters of iron(II) 1-nitroso-2-naphtholate complex are interpreted by assuming the presence of iron(III) and iron(II) complex species. Partial oxidation of iron(II) by 1-nitroso-2-naphthol is suggested.
Restricted Rotation Involving the Tetrahedral Carbon. X. Barriers to Rotation of Methyl Groups in 9-Methyltriptycene Derivatives.
Authors: Nakamura Mikio , Oki Michinori , Nakanishi Hiroshi , Yamamoto Osamu 
Published: July 2006

Abstract
Several 9-methyltriptycene derivatives have been synthesized and the PMR spectra examined at low temperatures. The compounds which have a methoxy or a methyl group at a peri position showed only broadening of methyl signals, whereas those with a chlorine at a peri position and another substituent at some other peri position showed a splitting of methyl signals. The compounds which have a halogen atom at a peri position are the intermediary cases in a sense that they show separation of the signal into two with 1 : 2 relative intensities but fail to show fine splittings. Activation parameters for the rotation were obtained by total line shape analysis. Substituent effects have been discussed.
A New Synthesis of 3-Alkyl-2-hydroxy-2-cyclohexen-1-ones
Authors: Sato Kikumasa , Inoue Seiichi , Ohashi Masao 
Published: July 2006

Abstract
A New synthesis of 2-hydroxy-3-methyl-2-cyclohexen-1-one (Ia), a flavor component of coffee aroma, is described. The selenium dioxide oxidation of ethyl 1-methyl-2-oxocyclohexanecarboxylate (IIa) gave α-diketone (IIIa), which was then hydrolyzed and decarboxylated to afford Ia. The treatment of IIa with cupric chloride in 50% acetic acid also yielded Ia. The dimethyl sulfoxide oxidation of ethyl 3-bromo-1-methyl-2-oxocyclohexanecarboxylate (IV) afforded IIIa, along with 3-bromo-6-ethoxycarbonyl-2-hydroxy-6-methyl-2-cyclohexen-1-one (V). The halogenation of IIa produced dihalogeno ketoesters (VIa) (VIIa), which also yielded Ia in a pure state by means of a direct acidic hydrolysis or by a two-step hydrolysis using morpholine. Other allied compounds are also described.
Effect of Alcohols on the Micelle Formation of Nonionic Surfactants in Aqueous Solutions
Authors: Nishikido Nagamune , Moroi Yoshikiyo , Uehara Hiromoto , Matuura Ryohei 
Published: July 2006

Abstract
The variation of critical micelle concentrations (CMC) of polyoxyethylene lauryl ethers having various ethylene oxide chain lengths \barn(\barn=6, 11, 20, and 31) on addition of short chain alcohols to the surfactant aqueous solutions was determined at 20 °C. Thermodynamic quantities of micelle formation in methanol– and ethanol–water mixtures and in pure water were obtained in connection with the heat of micelle formation determined by direct calorimetry. Methanol and ethanol showed a CMC-increasing effect only, whereas the addition of n-propanol, n-butanol, and n-pentanol showed a CMC-decreasing effect. The overall CMC-increasing effect is interpreted as being mainly due to the fact that methanol and ethanol weaken the hydrophobic bond. However, the effect also has a secondary effect of lowering the CMC slightly on the polyoxyethylene portion of a surfactant. Several factors are suggested for explaining this secondary effect. The CMC-decreasing effect is explained by a decrease in the free energy of mixing resulting from the solubilization of alcohol molecules into the micelle.
Determination of the Gauche Dihedral Angle and the Energy Difference between Rotational Isomers of Bromoacetyl Chloride
Authors: Tanabe Kazutoshi , Saëki Shinnosuke 
Published: July 2006

Abstract
Infrared absorption intensities of fundamental bands of bromoacetyl chloride were measured in carbon disulfide solution, an absolute intensity method being applied to determine the energy difference between the rotational isomers. In order to determine the dihedral angle of the less stable isomer, normal frequencies and band intensities were calculated for various angles, the results being compared with observed data. The dihedral angle of the gauche isomer was found to be 100°C which is in good agreement with the angle in chloroacetyl chloride. The energy difference, 0.91 kcal/mol, determined in carbon disulfide solution is in good agreement with the value obtained by the temperature variation method.
Polarographic Investigation of Dissolved Oxygen in Nonaqueous Solvent
Authors: Fujinaga Taitiro , Sakura Sachiko 
Published: July 2006

Abstract
In a common aprotic solvent, the dissolved oxygen is reduced to superoxide, and then to peroxide with tetraalkylammonium salt as the supporting electrolyte. With alkali metal ion as the supporting electrolyte, it is reduced further to form the third wave. All of these waves are controlled by the successive chemical reaction; namely if the products due to the successive reaction are stable, the reduction potential shifts to more positive direction. When the solvated ion of the supporting electrolyte is small, it forms stable complex with oxygen radicals, hence the reduction waves shift to positive potentials.
Characterization of the Oxalato Complex of Manganese(IV)
Authors: Yoshino Yukichi , Taminaga Iwao , Kokiso Masakazu , Uehiro Takashi 
Published: July 2006

Abstract
The preparation and analysis of the oxalato complex of manganese (IV), referred to as K2[Mn(OH)2(C2O4)2]·2H2O by Cartledge and Ericks, were reexamined. Measurements of magnetic moment confirmed the unusually low value, 2.48 B.M. at room temperature. The infrared spectra of the complex suggest the presence of oxide bridges between manganese atoms. The electrical conductance of aqueous solution of the complex salt at 0 °C has been measured in various concentrations. The results indicate that the complex anion is dimeric both in solid and in solution. The electronic spectra of the complex in powder and solution states were measured, and some decomposition processes discussed. It was proposed that the complex should be formulated as a dimer with two oxide bridges, [Mn2O2(C2O4)4]4−.
Alkoxythiocyanation and Alkoxyiodination of Olefins with Copper(II) Salts
Authors: Onoe Akira , Uemura Sakae , Okano Masaya 
Published: July 2006

Abstract
A simple and convenient method for the preparation of vicinal alkoxythiocyano- and alkoxyiodoalkanes is described. The reaction of olefins with copper(II) salts, such as chloride, bromide and sulfate, and potassium thiocyanate or iodide in alcohols readily affords the compounds in good yields. From vinyl acetates, alkyl vinyl ethers and α,β-unsaturated aldehydes, the products are obtained in the form of dialkyl acetals. The reaction mechanism is discussed.
Nuclear Magnetic Resonance Study of the Kinetics of Ligand Exchange on the Oxovanadium(IV)-malonato Complex
Authors: Tomiyasu Hiroshi , Ito Satoshi , Tagami Shiro 
Published: July 2006

Abstract
The kinetics of malonate exchange on VO(mal)22− has been studied by the NMR line-broadening method. The reaction was found to be dependent on the Hmal and hydrogen-ion concentrations, and the mechanism producing the intermediate complexes, where malonic acid was coordinated partly as an unidentate ligand, was estimated from the rate law. The activation parameters were determined for the acid-independent and acidcatalyzed paths as: ΔH\eweq=8.6 kcal/mol, ΔS\eweq=−16.2 e.u., and ΔH\eweq=8.9 kcal/mol, ΔS\eweq=−13.5 e.u.
Synthesis of Chelating Agents. XII. Chelating Behavior of 3,3-Dimethylbutane-1,2-diamine-N,N,N′,N′-tetraacetic Acid with Some Alkaline Earth Metals
Authors: Yano Tairoku , Yanagihara Yuzo , Kobayashi Hiroshi , Ueno Keihei 
Published: July 2006

Abstract
The chelate stability constants of 3,3-dimethylbutane-1,2-diamine-N,N,N′,N′-tetraacetic acid with some alkaline earth metal ions were determined at 25.0 °C and at an ionic strength of 0.10 with KNO3 as supporting electrolyte by a potentiometric method.
Radiotracer Studies of the Adsorption of an Ampholytic Surfactant, N-dodecyl-β-alanine, at the Aqueous Surface
Authors: Okumura Takeo , Nakamura Akio , Tajima Kazuo , Sasaki Tsunetaka 
Published: July 2006

Abstract
A tritiated ampholytic surfactant, N-dodecyl-β-alanine, C10H21–(CHT)2–NH2+–(CH2)2–COO−, was synthesized, and the amount of adsorption on an aqueous surface was measured directly by the radiotracer method. The adsorption isotherm near the neutral pH region showed a saturation value of 3.73×10−10 mol/cm2 above the concentration of about 1/5 of the critical micelle concentration in the absence of added salt, and a value of 4.74×10−10 mol/cm2 above the critical micelle concentration in the presence of 1 mol/l NaCl. In the presence of 1 mol/l NaCl, no effect of pH on the adsorption was found. The Gibbs adsorption isotherm applicable to the aqueous ampholytic surfactant was derived. The observed amounts of adsorption in the presence and absence of NaCl were in good agreement with the values calculated from the Gibbs adsorption isotherm, using the surface tension data measured by the Wilhelmy plate method.
Hydrate Crystals of Alkali Metal-Chloranil and -Bromanil Salts and Their Optical and Magnetic Properties
Authors: Hiroma Shoji , Kuroda Haruo 
Published: July 2006

Abstract
The potassium-chloranil (K+·CA−), sodium-chloranil (Na+·CA−) and sodium-bromanil (Na+·BA−) salts were found to form hydrates when their crystalline powders are exposed to a humid air. In the single crystal spectrum of K+·CA−, the charge-transfer band significantly increased its intensity on hydration, exhibiting the same polarization as in the spectrum of the water-free state. It was concluded that CA− ions in the hydrate crystal are closely stacked on each other to form columns as in the water-free crystal and the charge transfer interaction between CA− ions is stronger in the hydrate crystal than in the water-free crystal. The spin concentration of K+·CA− markedly decreased on hydration, it being 2.2×1022 spins per mol in the state of hydrate while 5.5×1023 spins per mol in the water-free state. The hydration resulted in an increase of the intensity of charge-transfer band and a decrease of the spin concentration also in the cases of Na+·CA− and Na+·BA−. It is also shown that organic solvents such as acetone, methy ethyl ketone and dichloromethane can enter into the crystal lattice of K+·CA− to form the solvent-containing crystals.
Binuclear Metal Complexes. XI. Substituent Effect upon Magnetisms of Binuclear Oxovanadium(IV) and Copper(II) Complexes of the Schiff Bases, 2,6-Bis[N-(2-hydroxy-5-substituted-phenyl)iminomethyl]-4-methylphenol
Authors: Okawa Hisashi , Ando Isao , Kida Sigeo 
Published: July 2006

Abstract
Binuclear oxovanadium(IV) and copper(II) complexes, M2(fsalap-R)(OMe) (R=H, CH3, Cl, and NO2) were synthesized and characterized, where H3fsalap-R denotes 2,6-bis[N-(2-hydroxy-5-substituted-phenyl)iminomethyl]-4-methylphenol and the metal ions are connected by the phenolic oxygen and a methanolate ion. The cryomagnetic properties of the complexes except Cu2(fsalap-NO2)(OMe) could be interpreted on the basis of the Bleaney-Bowers equation. It was found that the -2J values for the oxovanadium(IV) complexes increase in the order (VO)2(fsalap-CH3)(OMe)&lt;(VO)2(fsalap-H)(OMe)&lt;(VO2)(fsalap-Cl)(OMe), while those for the copper (II) complexes decrease in the order Cu2(fsalap-CH3)(OMe)&gt;Cu2(fsalap-H)(OMe)&gt;Cu2(fsalap-Cl)(OMe). These facts could be reasonably explained in terms of the difference in structures and spin-exchange mechanisms between the oxovanadium(IV) and the copper(II) complexes. (VO)2(fsalap-NO2)(OMe) showed a very strong antiferromagnetic spin-exchange interaction (−2J=545 cm−1) compared with the other complexes (180–280 cm−1). On the other hand, the magnetism of Cu2(fsalap-NO2)(OMe) could be interpreted in terms of the Ising model.
Nitration of 9,10-Dimethylanthracene and 9,10-Diethylanthracene
Authors: Suzuki Hitomi , Yoneda Hajime , Hanafusa Terukiyo 
Published: July 2006

Abstract
9,10-Dimethylanthracene gave 9-nitromethyl-10-methylanthracene as a major product, when treated with fuming nitric acid in dichloromethane at low temperatures. In contrast, 9,10-diethylanthracene yielded 9-nitro-10-hydroxy-9,10-diethyl-9,10-dihydroanthracene, which in refluxing alcohol was readily converted into 9,10-dialkoxy-9,10-diethyl-9,10-dihydroanthracene. Possible reaction sequences for the side-chain nitration have been discussed.
Oxidation of 1-Cyclohex-1-enecarbaldehyde and Related Compounds with Caro’s Acid
Authors: Ito Masaaki , Abe Kazuo , Abe Hideo , Yamada Keiichi , Masamune Tadashi 
Published: July 2006

Abstract
Three cyclic α,β-unsaturated aldehydes (1–3) were oxidized with an equivalent of Caro’s acid in methanol, giving both simple oxidation products and the corresponding norketones in moderate yields.
Substituent Effect in the Nucleophilic Attack by the Bromide Ion on the p-Tolyl-Substituted Phenyliodonium Ions
Authors: Yamada Yorinobu , Kashima Koichi , Okawara Makoto 
Published: July 2006

Abstract
p-Tolyl-substituted phenyliodonium bromides were prepared and their nucleophilic substitution reactions were carried out in the DMF solution and molten state. Their substituent effects were discussed from the reaction products and the spectra of the iodonium salts.