bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper(II) Complexes of Histidine and Its Related Compounds in Aqueous Solutions
Authors: Aiba Hiroji , Yokoyama Akira , Tanaka Hisashi
Published: July 2006

The copper(II) complexes of histidine and its related compounds in aqueous solution were investigated by potentiometric, spectrophotometric, and magnetic methods. The presence of a diolated binuclear copper(II) complex was indicated in the 1 : 1 histamine-copper(II) system by quantitative analysis of the titration data and the antiferromagnetic character of the complex. The titration data could not be quantitatively interpreted owing to precipitation, but the formation of a similar diolated copper(II) complex was also shown in the 1 : 1 histidinecopper(II) system by the magnetic properties of the complex. From a comparison of the spectral properties of the pertinent complexes, it was shown for the neutral 2 : 1 histidine-copper(II) complex that histidine binds to copper(II) through the amino and imidazole groups in the chelate plane and through the carboxyl group in the apical position. In the copper(II) complexes of histidine and histamine, it was shown that ionization of the pyrrole nitrogen of the imidazole ring is promoted, causing a spectral blue shift.
X-Ray Photoelectron Spectroscopy of Oxine-Metal Chelates
Authors: Yoshida Tooru , Sawada Shigemasa
Published: July 2006

Photoelectron spectra of oxine-metal chelates were measured. The chemical shifts of the N(ls) electron binding energy were smaller than 0.7 eV. There were nearly linear relations between the chemical shifts and the electronegativities of metals or the partial ionic characters of the nitrogen-metal bonds of chelates.
Some Substituted 1H,4H- and 1H,5H-Pyrazolo[4,3-c]pyrazoles. Syntheses and Properties
Authors: Lee Joung Hee , Matsumoto Akira , Yoshida Masayuki , Simamura Osamu
Published: July 2006

1,4-Dimethyl-3,6-diphenyl-, 1,5-dimethyl-3,3-diphenyl-, and 4-methyl-2,3,6-triphenyl-pyrazolo[4,3-c]pyrazoles(IV, V, and VIII) were prepared and their structures were established on the basis of their spectral data.
Theoretical Calculation of the Carbon-13 Chemical Shifts of Some Normal Alkanes by the Linear Combination of Gauge Invariant Atomic Orbitals-Molecular Orbital Theory Using INDO and MINDO/2 Methods
Authors: Ando Isao , Nishioka Atsuo , Kondo Masahiro
Published: July 2006

The 13C chemical shifts of several n-alkanes (CH4, C2H6, C3H8, C4H10, C5H12, C6H14, and C7H16) were calculated using a linear combination of the gauge invariant atomic orbitals-molecular orbital theory of Pople and the INDO and MINDO/2 methods, and the results were compared with the experimental data reported by Grant et al. The calculated chemical-shift differences among the carbons in these molecules were found to agree with the observed data except in some cases, whereas the observed order of the chemical shift of the carbons in n-alkanes, which have more than two magnetically nonequivalent carbons, cannot be interpreted by means of the average excitation energy (ΔE) approximation. Histograms showing the distribution of the excitation energies from the occupied to unoccupied orbitais were obtained and compared with ΔE.
Bitter Principles of Isodon umbrosus Hara. The Structures of Umbrosin A and B
Authors: Kubo Isao , Kamikawa Tadao , Isobe Takahiko , Kubota Takashi
Published: July 2006

Two new ent-kaurene derivatives have been isolated from Isodon umbrosus Hara and formulated by spectroscopic and chemical evidence as structures (1) and (2), respectively. Antimicrobial activity has been tested.
Photo-induced Condensation Reaction of p-Quinones with Aldehydes
Authors: Maruyama Kazuhiro , Miyagi Yo
Published: July 2006

The quantum yield of a photo-induced condensation product between a p-quinone and an aldehyde was determined, the reaction course being investigated by CIDNP technique.
The Microwave Spectra and r0, rs, and rm Structures of Ethylene Oxide
Authors: Hirose Chiaki
Published: July 2006

The rotational spectra of ten isotopic species of ethylene oxide, 12C2H416O, 12C13CH416O, 12C2H418O, 12C2H3D16O, cis- and trans-12C2H2D216O, 12C13CH2D216O, and 12C2H2D218O were observed. A least-squares fit including centrifugal distortion effect to the first order was made to derive the effective values of the A′, B′, C′, τ′aaaa, τ′bbbb, τ′cccc, and τ′aabb parameters and their correlation factors; τ′bbcc and τ′aacc were found to be insignificant. The rotational constants were used to determine the r0, rs, and rm structures. The structural parameters were derived as:

& r_0(CC)=1.470±0.003, r_s(CC)=1.466±0.002, r_m(CC)=1.462±0.003,

& r_0(CH)=1.085±0.004, r_s(CH)=1.085±0.001, r_m(CH)= 1.086±0.004,

& r_0(CO)=1.434±0.002, r_s(CO)=1.431±0.001, r_m(CO)=1.428±0.002,

& ∠_0HCH=116.28±0.69, ∠_SHGH=116.61±0.09, ∠_mHGH=116.92±0.69,

θ0=22.34±0.46, θs=21.99±0.11, θm=21.63±0.48 in units of Å and degrees; θ represents the angle of the H2C plane to the CC bond. The indicated error limits are 2.5 times the variances.
Kinetic Studies of the Reactions of the Ferricyanide Ion with Cobalt(II)-Aminopolycarboxylate Complexes
Authors: Ogino Hiroshi , Takahashi Masatake , Tanaka Nobuyuki
Published: July 2006

Kinetic studies of the reactions of the ferricyanide ion with cobalt(II)-aminopolycarboxylate complexes were carried out. The aminopolycarboxylates used in this study were trimethylenediaminetetraacetate (TRDTA), trans-1,2-cyclohexanediaminetetraacetate (CyDTA), propylenediaminetetraacetate(PDTA), and N-hydroxyethyl ethylenediaminetriacetate(HEDTA). The first step in the reaction is the rapid formation of a binuclear complex intermediate, [(ammopolycarboxylate)CoIIINCFeII(CN)5]n−(n=5 for TRDTA, CyDTA and PDTA and 4 for HEDTA), followed by the dissociation of the intermediate to ferrocyanide and Co(III)-aminopolycarboxylate ions. The equilibrium constant of the formation reaction and the rate constant of the dissociation reaction of the intermediate at an ionic strength of 0.66 were 6.2×102 M−1 and 2.0×10−2 s−1 respectively for the TRDTA system at 5 °C, 3.3×10 M−1 and 2.7×10−2 s−1 for the CyDTA system at 25 °C, and 2.4×103 M−1 and 3.0×10−3 s−1 for the PDTA system at 25 °C. The rate constant of the dissociation of [hedta CoIIINCFeII(CN)5]4− was found to be smaller than 1×10−4 s−1 at 25 °C and at an ionic strength of 0.66.
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

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

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

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

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

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

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.
Syntheses of α-Hydroxyamino Acids from α-Keto Acids
Authors: Ahmad Afzal
Published: July 2006

A new general method for the synthesis of α-hydroxyamino acids has been developed. Lithium cyanohydridoborate reduces α-keto acid oximes to the corresponding α-hydroxyamino acids and not to the corresponding α-amino acids.
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

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

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

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

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

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<100 μs), and the second-order kinetics (t<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

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

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

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

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

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

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

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

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

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

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

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

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

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

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)<(VO)2(fsalap-H)(OMe)<(VO2)(fsalap-Cl)(OMe), while those for the copper (II) complexes decrease in the order Cu2(fsalap-CH3)(OMe)>Cu2(fsalap-H)(OMe)>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

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

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

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.
The Formation of Substituted Quinazolines from Substituted Indoles by the Sensitized Photo-oxygenation in the Presence of Ammonium Acetate
Authors: Maeda Koko , Mishima Tamako , Hayashi Taro
Published: July 2006

2,4-Di- and 2,4,6-trisubstituted quinazolines (II) were prepared from 2,3-di- and 2,3,5-trisubstituted indoles (I) respectively by the sensitized photo-oxygenation in aqueous methanol in the presence of ammonium acetate or by fusion with ammonium acetate after the photo-oxygenation. Chemical evidences that II was produced via the hydroperoxide (III) of the indole and then the dicarbonyl compound (IV) were provided.
An ESR Study of Methylamino Radicals Photoproduced on the Porous Vycor Glass Surface
Authors: Hatano Keiichiro , Shimamoto Norio , Katsu Takashi , Fujita Yuzaburo
Published: July 2006

The photochemical decomposition of methylamines adsorbed on the surface of the porous Vycor glass was studied at 77 K by the ESR method, and the ESR spectra of the methylamino radicals, CH3NH, CH3ND, CD3NH, CD3ND, CH2DNH, and CH2DND, were observed as primary radicals from variously-deuterated methylamines upon irradiation with the light of a low-pressure mercury lamp. This result shows that the primary process is preferentially a rupture of the N–H or N–D bond of methylamine. These spectra were characterized by an apparent quenching of the N-hyperfine splitting resulting from large hyperfine anisotropy, and by nearly isotropic proton hyperfine splittings in both methyl and amino groups. The hyperfine splitting constants of the N, H, and D nuclei of each radical were determined, and consequently a D-substitution effect on the β-proton hf splitting in the methyl group was found. The characteristics of the ESR spectra were discussed in relation to the adsorbed state of the methylamino radical on the porous Vycor glass surface.
X-Ray Photoelectron Spectroscopy of EDTA
Authors: Yoshida Tooru , sawada Shigemasa
Published: July 2006

The binding energies of N(1s) in ethylenediaminetetraacetic acid (EDTA) and its related compounds were measured by means of a photoelectron spectrometer, and the molecular structures of EDTA were discussed. Two kinds of peaks were observed in the N(1s) spectra of EDTA and its related compounds, with binding energies of about 401 and 399 eV. In EDTA-4H, the heights of the two peaks were almost equal, while in its sodium salts the peak height with the higher binding energy decreased as the number of carboxylate groups in the molecule increased. In EDTA-4Na, only a single peak with a low binding energy was observed. In EDTP-4H and GEDTA-4H, the spectra showed two peaks with different heights. The binding energy values of the main peaks of simple amino acids, such as glycine and alanine, were about 401 eV. From the above results, it can be deduced that there are two kinds of N atoms, =N+H– and =N– types, in an EDTA molecule.
ESR of Copper(II) Complexes in Magnetically Non-dilute Crystals. II. Polycrystals of Various Bis(amino acidato) copper(II) Complexes
Authors: Yokoi Hiroshi
Published: July 2006

The molecular g values of several bis(amino acidato) copper(II) complexes in crystals, whose crystal structures with two molecules per unit cell are known, have been estimated from the crystal g values by considering the effect of the spin-exchange interaction between the dissimilar copper(II) ions. All the crystal g values have been determined here from the powder K-band ESR spectra. Many other complexes with unknown crystal structures have also been dealt with in a similar way. The results have indicated that most of the complexes probably have a tetragonal or nearly tetragonal copper (II) ion environment in crystals, and a tendency for the estimated g⁄⁄ value to decrease with an increase in the energy of the visible absorption peak in crystals have been noted. A discussion about the correlation between an axial molecular g tensor and the two copper-ligand bond lengths of Cu–O and Cu–N has been given.
Vibrational Spectrum of Trisdimethylaminocyclopropenium Perchlorate
Authors: Yoshida Zen-ichi , Tawara Yoshiyuki , Hirota Shizue , Ogoshi Hisanobu
Published: July 2006

Infrared spectrum in the region 4000–100 cm−1 and Raman spectrum of trisdimethylaminocyclopropenium perchlorate (1) have been measured. Band assignments have been made on the basis of normal coordinate analysis and deuteration of the methyl groups. Remarkable stabilization of cyclopropenium ion due to the peripheral amino groups is attributed to a marked delocalization of the positive charge of the ring on the amino groups through conjugation. Peculiar electronic structure of trisaminocyclopropenium ion is explained in terms of its vibrational spectrum.
Standard Potentials of Alkali Metals, Silver, and Thallium Metal/Ion Couples in N,N′-Dimethylformamide, Dimethyl Sulfoxide, and Propylene Carbonate
Authors: Matsuura Niro , Umemoto Kisaburo , Takeuchi Zen’ichi
Published: July 2006

The relative standard potentials of alkali metals, silver, and thallium metal/ion couples in N,N′-dimethylforrnamide(DMF), dimethyl sulfoxide(DMSO), and propylene carbonate (PC) were measured against an aqueous saturated calomel electrode(SGE). These standard potentials of lithium, sodium, potassium, rubidium, caesium, thallium, and silver are −3.237, −2.898, −3.116, −3.079, −3.079, −0.643, and +0.372 V vs. SGE respectively in DMSO, and −3.163, −2.830, −3.067, −3.040, −3.048, −0.559, and +0.538 V vs. SGE respectively in DMF, and −2.9064, −2.691, −3.002, −2.980, −2.986, −0.402, and +0.813 V vs. SGE respectively in PC. The thallium electrode was found to be stable enough to be used as a reference electrode in these solvents. For the purpose of examining the Debye-Hückel equation for estimating the activity coefficient, the formal potentials of the thallium electrode were measured at various ionic strengths. The Debye-Hückel equation was confirmed to be applicable in these solvents, provided a proper value was chosen for the ionic radius parameter, a, for each solvent–3.6 for DMSO, 5.0 for DMF and 0.0 for PC.
The Photochemistry of 2-Quinolinecarbonitriles. II. A Mechanism of the Photoinduced Substitution Reaction
Authors: Hata Norisuke , Saito Tsugio
Published: July 2006

In order to elucidate the mechanism of the photoinduced substitution reaction of 2-quinolinecarbonitrile in alcohols or ethers, measurements of the absorption and fluorescence spectra and the photochemical reactions were carried out in ethanol, t-butyl alcohol, or diethyl ether; consequently, an interesting relationship has been found to exist between the fluorescence intensity and the photoreactivity. The photosubstitution reaction can reasonably be assumed to be initiated by a hydrogen-atom abstraction from an alcohol or ether by the nitrogen atom of the quinoline nucleus. The experimental results indicated that such a hydrogen-atom abstraction was markedly facilitated by a hydrogen-bond formation of the nitrogen lone pair of the quinoline nucleus with ethanol or water: further, the reactive excited singlet state (S1) was presumed to be of a π,π* nature.
Vacuum Ultraviolet Absorption and Photoelectron Spectra of Aliphatic Ketones
Authors: Ogata Hitoshi , Kitayama Jun , Koto Masanori , Kojima Shinji , Nihei Yoshimasa , Kamada Hitoshi
Published: July 2006

The vacuum ultraviolet absorption spectra down to 65000 cm−1 and Hel photoelectron spectra were measured for CH3CHO and RCOCH3 (R=CH3 to t-C4H9). Assignments of the absorption bands are proposed with the aid of photoelectron spectra and CNDO/2 type molecular orbital calculations. Special notice has been paid to the similarity of the vibrational structure between the lowest ionization potential bands of photoelectron spectra and the second bands of vacuum ultraviolet absorption spectra.
Molecular Vibrations and Force Fields of Alkyl Sulfides. VII. Polythiomethylene (PTM) and Polythiomethylene-d2 (PTM-D2), and Their Model Compounds: CH3S(CH2S)nCH3 (n=1–3)
Authors: Ohsaku Masaru
Published: July 2006

Infrared spectra of polythiomethylene (PTM) and polythiomethylene-d2 (PTM-D2) observed by a Nujol mull method are reported, and their spectra are assigned. Normal coordinates of bis (methylthio)methane, CH3SCH2SCH3, bis(methylthiomethyl) sulfide, CH3SCH2SCH2SCH3, bis[methylthio(methylthio)]methane, CH3SCH2SCH2SCH2SCH3, PTM, and PTM-D2 have been treated. The force field used in the computation is a modified Urey-Bradley type. The skeletal conformation of these model compounds in the solid state is confirmed to be the [G] form. The relations between the degree of n and their CH2 deformation fundamentals are explained by the concept of the frequency-phase difference. The calculated frequencies are compared with those of experiment. A comparison of the force fields of PTM and polyoxyme hylene (POM) is also briefly made.
Polymerizationn of Vinyl Compounds by Dihydridotetrakis-(triphenylphosphine)ruthenium(II)
Authors: Komiya Sanshiro , Yamamoto Akio , Ikeda Sakuji
Published: July 2006

Dihydridotetrakis(triphenyIphosphine)ruthenium(II) 1 initiates the polymerization of α-substituted olefins of high e-values such as acrylonitrile and forms unstable complexes with olefins of low e-values. Molecular weight of the polymer obtained by the polymerization of acrylonitrile with 1 was independent of polymerization time and increased linearly with the monomer concentration. The rate of polymerization was measured by a dilatometry and compared with the rate of decomposition of 1 in the presence of acrylonitrile followed by a spectroscopic method. The rate of decomposition of 1 was found to be equivalent to the rate of initiation of polymerization and can be expressed by the following equations:

-\fracddt[Ru]=k[Ru], \frac1k=A+{B+C[PPh_3]}/[monomer]

On the basis of the kinetic results and the independence of molecular weight of the polymer on time, a mechanism involving a slow initiation step followed by rapid propagation and termination steps is proposed.
ESR Study of MoO3 Obtained from Thermal Decomposition of Ammonium Molybdate
Authors: Mann R S , Khulbe K C
Published: July 2006

The thermal decomposition of ammonium molybdate, between 100–600°C was studied by ESR technique. At 250 °C all ammonium molybdate was decomposed into molybdenum trioxide. Samples taken at 250, 300, 350, 400 and 450 °C all gave ESR signals. Samples at other temperatures (higher and below of this temperature range) did not give any ESR signal. The ESR signals were due to the formation of Mo5+ and Mo3+ ions. The maximum ESR intensity was observed for the sample (MoO3) at 300 °C. The different colouration of molybdenum trioxide formed at different temperature, was due to Mo5+ and Mo3+ ions.
Complexing Behaviour of 5-Amino-1,3,4-Thiazole-2-thiol. II. Complexes of Ni(II), Rh(I), Pd(II), Pt(II), Au(III) and Cu(II)
Authors: Gajendragad M R , Agarwala U
Published: July 2006

Complexes of Ni(II), Rh(I) Pd(II), Pt(II), Au(III) and Cu(II) with 5-Amino-1,3,4-thiadiazole-2-thiol have been prepared. Probable structures have been proposed for the complexes on the basis of visible and infrared spectral and magnetic susceptibility data and results of chemical analysis. Crystal field parameters have been calculated wherever possible.
Eetyl Radical Formed in the Grignard Reaction of 2-Methylbenzophenone
Authors: Okubo Masao
Published: July 2006

The radical in the title reaction gave an ESR spectrum different from that of potassium-ketyl. From studies using the deuterium label technique, the reason for this difference was ascribed to the suppression of the twisting vibration caused by aggregate-formation.
Reaction of Benzyne with N-Benzylideneaniline
Authors: Nakayama Jyuzo , Midorikawa Hiroshi , Yoshida Masayuki
Published: July 2006

Benzyne, generated from benzenediazonium-2-carboxylate and 2-carboxybenzenediazonium chloride, reacted with N-benzylideneaniline to give N-(o-anilinobenzhydryl)aniline (I) and 5,6-dihydro-5,6-diphenylphenanthridine (II) as final products.
New Furanosesquiterpenes from Ligularia Fischeri Turcz. 1β, 10β- Epoxyfuranoeremophilan-6β-ol and Its Derivative
Authors: Sato Toshichika , Moriyama Yoshihiko , Nagano Hajime , Tanahashi Yoshiaki , Takahashi Takeyoshi
Published: July 2006

Two new furanosesquiterpenes, isolated from Ligularia Fischeri Turcz. (collected at Shiramine), were shown to be 1β,10β-epoxyfuranoeremophilan-6β-ol (1) and 1β,10β-epoxyfuranoeremophilan-6β-yl 2-hydroxymethylprop 2-enoate (2).
Molecular Complexes of Arenetricarbonylchromium, -molybdenum and -wolfram
Authors: Kobayashi Hiroshi , Kobayashi Mitaka , Kaizu Youkoh
Published: July 2006

Arenetricarbonylchromium forms a charge-transfer complex with 1,3,5-trinitrobenzene (1,3,5-TNB), while arenetricarbonylmolybdenum and -wolfram do not form a charge-transfer complex with 1,3,5-TNB. On the other hand, arenetricarbonylchromium, -molybdenum and -wolfram form a charge-transfer complex with tetracyanoethylene (TCNE). Since the intramolecular charge transfer from coordinated arene to carbonyls increases in the molybdenum and wolfram derivatives, 1,3,5-trinitrobenzene cannot form a molecular complex accepting an electronic charge of the coordinated arene. In the case of TCNE, however, a molecular complex is formed by an inner-sphere charge-transfer interaction between the acceptor and the central metal atom. Thus the stability of the TCNE molecular complexes is dependent upon the charge density of the central metal atom and also the steric effects due to the functional groups in coordinated arenes. The ionization potentials of the molybdenum and wolfram derivatives observed for their TCNE molecular complexes are almost equal but higher than those of the corresponding chromium derivatives, whereas the highest stability is obtained for the molybdenum derivatives.
The Cd 5 3P0 State in the Cadmium-photosensitized Reaction and the Quenching of the Resonance Radiation at 326.1 nm by Nitrogen, Carbon Monoxide, and Carbon Dioxide
Authors: Yamamoto Shunzo , Takaoka Motoaki , Tsunashima Shigeru , Sato Shin
Published: July 2006

The emission of the resonance line at 326.1 nm (5 3P1→5 1S0) and the absorptions of Cd(3P0) at 340.4 nm (5 3D1←5 3P0) and of Cd(3P1) at 346.6 nm (5 3D2←5 3P1) have been measured as functions of the pressure of foreign gases at 250°C. At the pressures higher than 1 Torr of any rare gas, an equilibrium was established between 5 3P1 and 5 3P0 states. The efficiency of nitrogen in producing the 5 3P0 state from the 5 3P1 state was found to be more than 103 times those of rare gases. The quenching efficiencies of nitrogen, carbon monoxide, and carbon dioxide for the resonance radiation at 326.1 nm were also measured by using argon as the diluent gas. The halfquenching pressures obtained were 73±3, 0.47±0.01, and 0.096±0.003 Torr for nitrogen, carbon monoxide, and carbon dioxide respectively.
Deoxygenation of Sulfoxides to Sulfides in an Iodine–Pyridine–Sulfur Dioxide System
Authors: Nojima Masatomo , Nagata Tsuyoshi , Tokura Niichiro
Published: July 2006

Sulfoxides were deoxygenated quantitatively in an iodine-pyridine-sulfur dioxide system under mild reaction conditions. The same reaction also occurred with bromine.
The Contribution of the Double Collision Occurring in an Atom to the Yield of the Ionization and Excitations of Noble Gases Irradiated by 100 keV Electrons
Authors: Okazaki Kiyoshi , Sato Shin , Ohno Shin-ichi
Published: July 2006

Gryzinski’s classical treatment of the double ionization has been used to estimate the contribution of the double-collision process to the G-values of the ionizations and excitations of noble gases irradiated by 100 keV electrons. Except for helium, the double collision accounted for 5–15% of the yield of electrons. The total G-values calculated are ultimately as follows (in the order of He, Ne, Ar, Kr, and Xe): 2.28, 2.53, 3.09, 3.41, 3.67 for G(electrons); 0.84, 1.37, 1.78, 1.54, 1.41 for G(excited singlet states); 0.17, 0.07, 0.13, 0.23, 0.39 for G(triplet states).
Ruthenium Complexes with Coordinated Hydroxyiminoacetylacetonato or Bridging Nitrosyl Groups Formed by the Reactions of Nitrosylruthenium(III) with Acetylacetone
Authors: Mukaida Masao , Nomura Terunosuke , Ishimori Tatsujiro
Published: July 2006

Complexes formed by the reactions of nitrosylruthenium(III) with acetylacetone were investigated. The following products: [Ru(acac)2(hia)], 1; cis-[RuCl(NO)(acac)2], 2; and [Ru(NO)(acac)24], 3; (acac=C5H7O2− and hia=C5H6NO3−), were isolated as crystals and were characterized. On the basis of chemical and thermal analyses, and on the basis of observations of the magnetic properties, the conductivities, the molecular weights, the infrared spectra, and the NMR spectra, it was concluded that 1 contains the hydroxyiminoacetyl acetonato ligand, which is formed by the reaction of the coordinated nitrosyl group with acetylacetone, and that 2 contains a terminal nitrosyl group, and 3, bridging nitrosyl groups.
Intramolecular Oxypalladation. Cyclization Reaction of 2-Allylphenols with Palladium Salts
Authors: Hosokawa Takahiro , Ohkata Hisao , Moritani Ichiro
Published: July 2006

The stoichiometric reaction of sodium salts of 2-allylphenols 1 with dichlorobis(benzonitrile)palladium(II) gives generally 2-substituted benzofurans 2 in moderate yields. The formation of cyclized products is explained by intramolecular oxypalladation followed by elimination of a palladium hydride species. The cyclization can be made catalytic by using palladium(II) acetate, cupric acetate, and oxygen.
The Crystal and Molecular Structure of Sterigmatin, A Metabolite of Aspergillus versicolor
Authors: Fukuyama Keiichi , Tsukihara Tomitake , Katsube Yukiteru , Hamasaki Takashi , Hatsuda Yuichi , Tanaka Nobuo , Ashida Tamaichi , Kakudo Masao
Published: July 2006

The crystal structure of sterigmatin has been determined by single-crystal X-ray analysis. The crystals are triclinic; space group P1, Z=2, with a=14.392(4), b=14.120(4), c=4.256(2) Å, α=78.22(3), β=100.42(3), γ=56.90(3)°. The structure was refined to an R value of 0.039 for 1961 reflections. There are two intramolecular hydrogen bonds in each of the crystallographically independent molecules.