bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Activation Energies of Radical Substitution Reactions in the Gaseous Phase. I. An Empirical Method Employing the Morse Function
Authors: Kagiya Tsutomu , Sumida Yūzō , Inoue Tokuji , Dyachkovskii Fridrich S
Published: July 2006

An empirical evaluation of the activation energy has been carried out for the radical substitution reaction involving polyatomic molecules. The potential energy along the reaction path is assumed to be expressed for the initial and the final systems by the two Morse functions with the coefficient “a′,” which is different from the “a” in the usual Morse function of the bond. The difference between the a′Δr* values in the Morse functions of the initial and the final systems in the transition state is empirically determined as a function, af′Δrf*–ai′Δri*=βQ, of the reaction heat, Q. From the Morse function with “a′” and the above relation, the activation energy is calculated by using the bond dissociation energies of the initial and the final molecules. The treatment proposed is useful for the evaluation of the activation energies of many types of radical substitution reactions.
The Photochemical Rearrangement of Phenyl Acetate
Authors: Shizuka Haruo , Morita Toshifumi , Mori Yuji , Tanaka Ikuzo
Published: July 2006

The photochemical rearrangements of phenyl acetate and p-substituted phenyl acetates have been studied. The quantum yields of the rearrangements of phenyl acetate in cyclohexane were independent of the irradiation time, the concentration of phenyl acetate (<2×10−2 mol/l), the temperature (20–70°C), and the presence of piperylene (a triplet quencher) or oxygen. The quantum yields for the formations of o- and p-hydroxyl acetophenones and of phenol were 0.17, 0.15, and 0.06 respectively in cyclohexane. Comparing the quantum yields for phenyl acetate rearrangements with those for p-methylphenyl acetate, the quantum yields for the predissociation of the O–CO bond and the back reaction, and the recombination ratio were estimated to be 0.61, 0.23, and 0.9 respectively in cyclohexane. The relative rate constants of the back reaction and the o- and p-rearrangements were parallel to the odd π electron densities of the phenoxy radical. These results have shown that the reaction scheme of phenyl acetate in the liquid phase at 2537 Å is similar to that of acetanilide.
Electron Spin Resonance Studies of the Formation of Anion Radicals on γ-Irradiated Silica Gel
Authors: Yamada Yoshio , Hasegawa Akinori , Miura Masaji
Published: July 2006

The ESR spectra assigned to the anion radicals of SO2−, (TCNE)− (tetracyanoethylene), and O2− were obtained for, respectively, sulfur dioxide, TCNE, and oxygen when these gases were adsorbed on γ-irradiated silica gel. As regards sulfur dioxide, a characteristic change in the concentration of the SO2− radical was observed during the post-irradiation with high-energy UV light. In the case of carbon dioxide, the CO2− radical was produced only when UV post-irradiation was added to γ-irradiation. The assignments were principally made in comparison with the reported g-values. Especially, the identification of the CO2− radical was ascertained by using 13C. The analyses of the g-factor for the O2− radical and of 13C hyperfine constants for the CO2− radical gave information on the interaction of the radicals on a solid surface with the cations in the adsorption center. In view of the fact that each of these molecules possesses a different degree of electron affinity, the results described above indicate that the electrons trapped in the defects of the silica gel surface transfer to the adsorbed molecules and that UV light promotes the electron transfer.
Kinetics of the Transition of Titanium Dioxide Prepared by Sulfate Process and Chloride Process
Authors: Suzuki Akira , Tukuda Ritushi
Published: July 2006

The kinetics of the phase transformation of anatase to rutile was studied by means of X-ray diffraction. Samples of anatase were prepared by sulfate and chloride processes. The kinetic data could well be expressed by the equation

α=1−e−btn,

where α is the fraction of anatase transformed in time t, and b and n constants. The activation energy of the phase transformation is 105 kcal/mol for the sample prepared by the sulfate process, and 107 kcal/mol for the sample prepared by the chloride process. These values of activation energy are compared with those previously obtained.
Mixed Conduction in Stabilized Zirconia at a Low Oxygen Partial Pressure
Authors: Hirota Kazushi
Published: July 2006

The electromotive force of the oxygen concentration cell, O2 gas/stabilized zirconia/Fe(+C)-melt+COgas, was measured at 1900°K as a function of the carbon concentration in iron melt, and the transference number of the stabilized zirconia was calculated. The transference number of the ions in the stabilized zirconia partition is less than unity over the whole range of carbon concentration. When the results are compared with the equations derived from plausible models, a reasonable coincidence is obtained.
Anionic Telomerizations of Styrene with Butylamines
Authors: Asahara Teruzo , Sen\={o} Manabu , Tanaka Sadayoshi , Den Norio
Published: July 2006

The anionic telomerizations of styrene with n-butylamine, s-butylamine, t-butylamine and isobutylamine catalyzed by sodium metal were investigated. The structures of the products were discussed by the NMR spectra obtained in carbon tetrachloride and identified to be N-butyl-2-phenylethylamines and N-butyldi(2-phenylethyl)amines. The general reaction scheme was proposed and interpreted with the concept of the anionic telomerization, where amine acts as a telogen and styrene as a taxogen.
Infrared Study of the Conformational Equilibria of meso- and racemic-2,3-Dichlorobutanes
Authors: Iimura Kazuyoshi , Kawakami Naoto , Takeda Masatami
Published: July 2006

The conformational equilibria of rotational isomers of meso- and racemic-2,3-dichlorobutanes were investigated in various solvents by an infrared method. The coexistence of three rotational isomers was found for each of the meso and racemic-2,3-dichlorobutanes. However, the equilibrium concentrations changed depending on the solvent dielectric constant. The equilibrium concentration of the less polar form of a rotational isomer, in which the conformation is extended trans with respect to the Cl–C–C–Cl linkage, decreased as the solvent dielectric constant increased. The energy differences between the rotational isomers in the gaseous state and in acetonitrile solvent were also discussed.
ESR Studies of Carboxylic Acid- and Ester-Radical Anions Produced by γ-Irradiation at 77°K
Authors: Nakajima Yukihiko , Sato Shin , Shida Shoji
Published: July 2006

A series of monocarboxylic acids and esters have been γ-irradiated at 77°K, either pure or in the rigid matrix of 2-methyltetrahydrofuran, and the products have been examined by ESR spectroscopy. The spectra obtained in the pure state showed that the primary paramagnetic species in each case is the corresponding radical anion, (Remark: Graphics omitted.). In the rigid matrix, these characteristic spectra have been obtained after illuminating the γ-irradiated sample with visible light at the expense of the spectra of trapped electrons. When ultraviolet light was used for the illumination, the spectra of the radical anions disappeared, but instead appeared the spectra of the radicals produced by the decomposition of the radical anions. The latter spectra were almost the same as those obtained by the direct photolyses of acids and esters.
Studies of the Estimation of the Interfacial Energy of Embryo in Solid-Liquid Systems
Authors: Nakai Tasuku
Published: July 2006

A novel method for the estimation of the interfacial energy of an embryo from the solubility data in solid-liquid systems has been proposed. The distribution function of embryos in solutions derived thermodynamically has been used as the base for the present treatment. The interfacial energies were calculated numerically for three different combinations of solute and solvent, namely, water-inorganic salt, water-organic compound, and organic solvent-organic compound. A fairly good linear relationship was observed between the interfacial energies calculated and the temperatures over the whole temperature range of solubility data. The semiempirical equation describing the relationship between the interfacial energy of the embryo and the temperature in the solid-liquid system was found to be exactly the same as that between the surface energy of the liquid in contact with gas through a free surface and the temperature. The size dependence of the interfacial energy has also been briefly described.
Temperature-jump Studies of the Kinetics of the Formation of the Monochloro and Monobromo Complexes of Iron(III)
Authors: Yasunaga Tatsuya , Harada Shoji
Published: July 2006

The temperature-jump method was used to study the kinetics of FeCl2+ and FeBr2+ complex formations in aqueous solutions. Complex formation is composed of two paths. In the acid-independent path, the rate-determining step of complex formation may be the reaction between Fe(H2O)53+ and X− (X−=Cl−, Br−). The other path is that via the hydrolysis of ferric ions, and the rate-determining step is the loss of a water molecule from the inner coordination sphere of the metal ion. The kinetic values obtained are in good agreement with the results obtained by the flow method.
Mössbauer Spectral Observation of α-Fe2O3 Supported on Silica Gel during Activation
Authors: Tachibana Taro , Ohya Toshie , Yoshioka Tohru , Koezuka Junji , Ikoma Hiroko
Published: July 2006

Mössbauer spectral studies were made of samples of α-Fe2O3 highly dispersed on silica gel before and after activation, which consisted of evacuated heating at 475°C. The spectra gave Ividence that Fe2+ ions were produced from α-Fe2O3 during the activation process. Reduction was impossible after the activation and oxidation had been repeated three times. However, the inactivated sample came to be again reduced by activation after having been exposed to water vapor at room temperature. In order to explain these facts, a working hypothesis was advanced that the hydroxyl groups near the surface of the particles play a principal role in reacting with organic contamination from the vacuum system, as a result bringing about the partial reduction of α-Fe2O3.
Thermodynamic and X-Ray Studies of Solid Solutions of Silver Bromide and Sodium Bromide
Authors: Tsuji Toshihide , Fueki Kazuo , Mukaibo Takashi
Published: July 2006

Activity, and partial molal free energy, enthalpy and entropy of AgBr in AgBr-NaBr solid solutions have been obtained at 350 and 400°C from the e.m.f. data of galvanic cells of the type Ag/AgBr-NaBr/Br2. It has been found that the solid solution forms a regular solution defined by Hildebrand. A miscibility gap has been found by the study of galvanic cells and confirmed by high temperature X-ray diffraction. A new phase diagram of the AgBr-NaBr system is presented.
Anharmonic Potential Constants and Vibrational and Rotational Parameters for Hydrogen Cyanide
Authors: Nakagawa Toru , Morino Yonezo
Published: July 2006

The general fourth-order potential constants, f, for hydrogen cyanide were determined by a least-squares analysis applied to the observed values of the vibrational energies and the rotational constants for six isotopic species, H12C14N, H13C14N, H12C15N, D12C14N, D13C14N, and D12C15N. The normal frequencies, ωi, the cubic and quartic potential constants, kijk and kijkl, the anharmonicity constants, xij, the vibration-rotation interaction constants, αi, and the Coriolis coupling constants, ζijx were calculated for the six isotopic species.
Polarographic Study of the Cadmium(II)-Ethylenediaminetetrapropionate Chelate
Authors: Kodama Mutsuo , Tominaga Yayoe
Published: July 2006

The d.c. polarographic behavior of the cadmium(II) ion in ethylenediaminetetrapropionate (EDTP) was studied in the pH range from 8.30 to 10.30. Over the entire range of experimental conditions employed, the cadmium(II)ion invariably gave a single well-defined wave corresponding to the following reversible two-electron reduction:

(Remark: Graphics omitted.)

Even in the presence of ammonia or the alaninate ion, the cadmium(II) ion in the EDTP solution also behaves reversibly in a polarographic electrolysis. However, the half-wave potential was found to be shifted to the more negative potentials by the addition of ammonia or alaninate. This was ascribed to the formation of a mixed ligand chelate involving ammonia or the alaninate ion. From the relation between the shift of the half-wave potential and the concentration of ammonia or alaninate, the composition and the stability constant of the mixed ligand chelate were determined and the electrode reaction was established as:

(Remark: Graphics omitted.)

where A means the ammonia or the alaninate ion. The K2, KNH3, and Kala values determined were 5.5×102, 1.38×102, and 2.61×104 respectively.
The Spectrophotometric Determination of Zirconium(IV) with Bromopyrogallol Red
Authors: Sakai Takayoshi , Funaki Yûko
Published: July 2006

Zirconium(IV) reacts with an excess of bromopyrogallol red to form a violet complex. The constant absorbance of a solution containing the complex is obtained in the pH range from 5.0 to 5.4 at 670 mμ. About 25 min is required to complete the chelate formation in a boiling water bath. The complex thus formed is stable for at least 3 hr. The color system obeys Beer’s law in the range from 4 to 35 μg zirconium in 25 ml. The sensitivity of the reaction is 0.002 μg per cm2 for an absorbance of 0.001. In composition the complex has a metal-to-ligand ratio of 1:2. The molar absorptivity and the apparent formation constant of the complex are calculated to be 7.01×104 at 670 mμ and 1.11×109 at pH 5.2 respectively. The effect of diverse ions on the determination is examined.
Preparation and Properties of Di-μ-alkoxo-bis(3-alkyl-5-methylsalicylaldehydato)dicopper(II)
Authors: Inazu Takako , Okawa Hisashi , Inazu Takahiko , Yoshino Tamotsu
Published: July 2006

In this paper, the syntheses of copper(II) complexes of 3-alkylsalicylaldehydes, B, as well as the syntheses and properties of dimeric copper(II) complexes, C, with bridged alkoxy groups are reported.
Cooxidation of Hydrocarbons in Liquid Phase. VI. Reactivities of Hydrocarbons and Peroxy Radicals
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto
Published: July 2006

Cooxidation of all the combinations of two hydrocarbons among styrene, α-methylstyrene, tetralin and cumene was studied at 70° C in the presence of azobisisobutyronitrile as a thermal initiator. The reactivity ratios for each binary mixture were determined by several appropriate methods. The relative reactivities of styrene, α-methylstyrene, tetralin and cumene toward the peroxy radicals were approximately in the ratio 15 : 10 : 5 : 1. It was also concluded that the secondary peroxy radicals were more reactive than the tertiary peroxy radicals and that the polymeric peroxy radicals were more reactive than the normal alkylperoxy radicals.
Synthetic Studies of the Flavone Derivatives. XII. The Synthesis of 8,3′-Dimethoxy-5,7,4′-trihydroxyflavone
Authors: Fukui Kenji , Nakayama Mitsuru , Horie Tokunaru
Published: July 2006

The partial benzylation of 3-methoxy-2,4,6-trihydroxyacetophenone gave a mixture of 2,4-dibenzyloxy-6-hydroxy- and 4,6-dibenzyloxy-2-hydroxy-3-methoxyacetophenone. The latter was esterified with 4-benzyloxy-3-methoxybenzoyl chloride, and the resulting ester was converted into 8,3′-dimethoxy-5,7,4′-tribenzyloxyflavone via the corresponding diketone. The catalytic debenzylation of the flavone gave 8,3′-dimethoxy-5,7,4′-trihydroxyflavone. Its diethyl ether was also prepared from 3,6-dimethoxy-4-ethoxy-2-hydroxyacetophenone by an unambiguous method.
The Synthesis of 3-Hydroxy-8,9-dimethoxypterocarpan
Authors: Fukui Kenji , Nakayama Mitsuru , Harano Teruo
Published: July 2006

7,2′-Dihydroxy-4′,5′-dimethoxyisoflavone was obtained from 7-hydroxy-2′,4′,5′-trimethoxyisoflavone by selective demethylation with aluminum chloride in acetonitrile. By partial benzylation, the dihydroxyisoflavone then gave 7-benzyloxy-4′,5′-dimethoxy-2′-hydroxyisoflavone. The subsequent treatment of the latter with sodium borohydride afforded 3-hydroxy-8,9-dimethoxypterocarpan via its 3-benzyloxy-compound.
Kinetic Studies of the Triethylenediamine-catalyzed Transamidation of 1,3-Diphenylurea with n-Butylamine in Dioxane
Authors: Furuya Yoshiaki , Itoho Kazuo , Miyagi Harue
Published: July 2006

The rates of the transamidation of 1,3-diphenylurea (abbreviated as DPU) with n-butylamine (BA) in dioxane in the presence of triethylenediamine (TED), forming n-butylphenylurea (BPU), aniline and carbon dioxide, were followed ultraviolet-spectrophotometrically. The rate of the reaction satisfied the following equation:

υ={k1′+k2′[TED]}[DPU]+{k2″+k3[TED]}[BA][DPU].

The first and second terms correspond to the non- and the TED-catalyzed hydrolysis of diphenylurea, while the third and fourth terms represent, respectively, the non- and the TED-catalyzed transamidation. In both the non- and the TED-catalyzed transamidation, a probable mechanism which involves the nucleophilic attack of the lone pair of the N-atom on the carbonyl C-atom of diphenylurea, followed by the formation of ion pairs of quaternary ammonium salt and of quaternary ammonium type salt, was discussed.
Aminosugars. XVII. Synthesis of Benzyl 2-Acetamino-2-deoxy-α-d-glucopyranosiduronic Acidamides and N-(2-Acetamino-2-deoxy-d-glucuronyl)-aminoacids
Authors: Yoshimura Juji , Sato Tadahide , Ando Hiroaki
Published: July 2006

Benzyl 2-acetamino-2-deoxy-α-d-glucopyranosiduronic acid was obtained by direct oxidation of the corresponding glucoside, and converted to esters (methyl, ethyl and benzyl) and amides (methyl, ethyl, phenyl and benzyl). Condensation of the uronic acid with aminoacid benzyl-esters (gly, l-ala, l-asp, and l-glu) by dicyclohexylcarbodiimide gave the corresponding amides, some of which were hydrogenated to N-(2-acetamino-2-deoxy-d-glucuronyl)-aminoacids. Acid hydrolysis of the peptides were examined.
Photoconductive Properties of Organic Polyiodides
Authors: Sano Toshihiko , Okamoto Kenichi , Kusabayashi Shigekazu , Mikawa Hiroshi
Published: July 2006

The photoconductive properties of (CH3)4N+I5−, (CH3)3(C6H5)N+I5−, N-methylacridinium pentaiodide and N-methylquinolinium pentaiodide were investigated by both a sandwich type cell and a single crystal cell. In the former arrangement, the photoresponse observed was the overlap of photoconductive response and photovoltaic response. The single crystal gave pure photoconductive response. Tetramethylammonium pentaiodide was the most photoconductive among the polyiodides. Spectral dependence of the photocondutcivity of this compound revealed that the threshold is at about 1000 mμ (1.24 eV). This value is in good agreement with the band gap energy 1.36 eV obtained from the temperature dependence of the dark current and 1.20–1.26 eV from calculation. Semiconductive properties of the organic polyiodides are explained by applying the band model.
Kinetics of Multidentate Ligand Substitution Reactions. VI. The Substitution Reaction of Diethylenetriaminepentaacetic Acid with the Nitrilotriacetato Nickelate(II) Chelate
Authors: Kodama Mutsuo
Published: July 2006

The kinetics of the substitution reaction of diethylenetriaminepentaacetic acid (DTPA) with the nitrilotriacetato nickelate(II) chelate have been studied polarographically in both acid and alkaline media. The reaction was found to be first-order with respect to DTPA and also first-order with respect to the nitrilotriacetato nickelate(II) chelate with 1-to-1 composition. In an acid solution the reaction proceeds mainly through tervalent and quadrivalent DTPA anions. On the other hand, in an alkaline solution the reaction proceeds through quadrivalent and quin-quevalent DTPA anions. The heat of activation and the entropy of activation for the three elementary reactions were estimated, and the effect of the protonation of the quinquevalent DTPA anion on the reaction rate was discussed.
Metal Complexes of Schiff Bases Obtained from Substituted Salicylaldehydes and 2-Aminopyridine Derivatives
Authors: Yamada Shoichiro , Yamanouchi Kuniko
Published: July 2006

Numerous metal complexes (abbreviated as M(X-SAL·R)2·nH2O) of Schiff bases obtained from substituted salicylaldehydes and 2-aminopyridine derivatives were prepared as crystals, where X=H, 5,6-benzo, 5-Cl, 5-Br, 5-NO2 and 3-CH3O, R=2-pyridyl, 2-(3-methylpyridyl), 2-(4-methylpyridyl) and 2-(6-methylpyridyl), and M=Co(II), Ni(II), Cu(II), Zn(II) and Pd(II). It is concluded, mainly from the electronic absorption spectra, that the cobalt (II) complexes are tetra-hedral, with one exception, which has an octahedral configuration with two water molecules coordinated to the cobalt(II) ion. The nickel(II) complexes are octahedral, and the copper(II) and the palladium(II) complexes are planar. In these metal complexes, the Schiff bases are bidentate, except bis(N-2-(6-methylpyridyl)-salicylideneiminato)nickel(II), in which the ligand functions as a terdentate.
Metal-Containing Initiator Systems. XVI. Radical Polymerization with Metal Carboxylates
Authors: Aoki Shuzo , Matsumura Seitaro , Otsu Takayuki
Published: July 2006

The polymerization of vinyl monomers with metal carboxylates has been investigated in benzene at 60°C. Gobalt(III) cyclohexanecarboxylate behaved as an effective initiator of the polymerization, and its activity was higher than that of corresponding salts of manganese (III) and copper(II), and than that of cobalt (III) acetylacetonate in the polymerizations of styrene (St) and methyl methacrylate (MMA). It was found that the overall rate of polymeriaztion (Rp) of MMA with cobalt (III) cyclohexanecarboxylate was expressed by the following equation, indicating that the polymerization proceeded through a free redical intermediate:

Rp=k[MMA]1.4[Co(III)]0.5

The free radical propagation of this polymerization was also supported by the results of the copolymerizations of St with MMA and with vinyl acetate; i.e., the resulting copolymer composition curves agreed with the typical free radical ones. It was assumed that the initiation of polymerization occurred by means of a radical produced by the homolysis of the metal-oxygen bond in the carboxylate. The reaction order with respect to MMA in the above equation, which was higher than unity, suggested the participation of the MMA molecule in initiating the radical formation.
The Absolute Configuration of Isopropylidenecamphor Oxide
Authors: Katsuhara Jun
Published: July 2006

The conversion of (+)-isopropylidenecamphor derived from (+)-camphor into (1R:2S:4S)-isopropylideneborneol and (1R:2R:4S)-isopropylideneisoborneol was described. In light of this configurational correlation, it was concluded that (+) -isopropylidenecamphor oxide derived from isopropylideneborneol has (1R:3R:4S)-, and (−)-isopropylidenecamphor oxide derived from isopropylideneisoborneol, (1R:3S:4S)-configurations.
Coumarins. VII. The Acid-catalyzed Reaction of Aromatic Compounds with β-Chlorocarboxylic Acids
Authors: Sato Kikumasa , Lin Yau-Shin , Amakasu Takeshi
Published: July 2006

The aluminum chloride-catalyzed reaction of aromatic compounds, such as benzene and phenols, with β-chlorocarboxylic acids was investigated. Although the reactions of benzene, toluene, and chlorobenzene with β-chloropropionic acid were found to give the corresponding dihydrocinnamic acids in high yields, attempts to prepare dihydrocoumarin by a similar reaction of phenol were unsuccessful. Similarly, β-arylbutyric acids were obtained in good yields by means of the aluminum chloride-induced reaction of aromatic hydrocarbons with β-chlorobutyric acid (Ib). In contrast, phenols, such as phenol, o- and m-cresols, reacted with Ib under similar conditions to provide the corresponding β-(p-hydroxyphenyl)butyric acids in 22–60% yields, while a 51% yield of β-(5-hydroxy-2-methylphenyl) butyric acid was obtained upon a similar treatment of p-cresol with the acid Ib.
Argentation Constants of Styrene Derivatives
Authors: Inaki Yoshiaki , Nozakura Shun-ichi , Murahashi Shunsuke
Published: July 2006

Equilibrium constants for the formation of silver ion complexes (argentation constants) of styrene derivatives in water were measured at 0 and 25°C by Andrews and Keefer’s solubility method. The argentation constants for the 1 : 1 complex (K1) decreased in this order: cis-β-alkylstyrene>α-alkylstyrene>trans-β-alkylstyrene, for a given alkyl group. This order was related to differences in the resonance stabilization of the double bond. The K1 values of the α- and β-alkylstyrene series did not seem to correlate with Taft’s steric substituent constant, Es, within the respective series. However, when the hyper conjugation effect of alkyl substituents was considered, a good linearity between logK1 and Hancock’s parameter, Esc, was obtained. Thus, the steric effect was separated from the hyperconjugation effect, and it was found that the steric effects for the three series are nearly identical. Thermodynamic data indicated that an isokinetic relationship holds between ΔH and ΔS and that the argentation equilibrium is controlled mainly by the entropy factor. The degree of methyl substitution at the double bond of styrene slightly influenced the K1 values, although 1,2-dihydronaphthalene had an abnormally large K1 value.
Sulfilimine. I. Synthesis and Formation Mechanism
Authors: Tsujihara Kenji , Furukawa Naomichi , Oae Keiko , Oae Shigeru
Published: July 2006

The kinetics of the reaction of sulfide and chloramine T was investigated. The reaction was very much affected by pH, and the rate reached the maximum at pH 5.5. The reaction was found to be facilitated by the substitution of an electron-releasing group in phenyl rings of aryl methyl sulfides. From these observations the rate-determining step appears to involve the formation of the sulfonium cation intermediate. From the mechanistic study of this reaction, an effective procedure for the synthesis of sulfilimine was devised.
Amine Derivatives of 1-(1′-Phenyl-2′-bromoethyl)-5-methyltetrazole
Authors: Terada Akira , Hassner Alfred
Published: July 2006

As part of search for a potential new type of antimalarial, several 1-(1′-phenyl-2′-aminoethyl)-5-methyltetrazoles were prepared by the amination of 1-(1′-phenyl-2′-bromoethyl)-5-methyltetrazole using various amines, such as mono- and diamines of aliphatic and alicyclic. The reaction in the presence of a large excess of amine occurred smoothly on heating at 100–130°C, and it gave the title product without any significant by-product such as the bistetrazole compound, even though a primary amine was used.
The Adsorption of Cobaltous Ions on Glass Beads from Extremely Dilute Aqueous Solutions
Authors: Seimiya Tsutomu , Kozai Hisako , Sasaki Tsunetaka
Published: July 2006

The adsorption of cobaltous ions on fine glass beads was measured for dilute aqueous 60CoCl2 solutions with pH values from 2 to 10 and with concentrations from 10−6 to 10−10 mol/l. The amount of the adsorption of cobaltous ions on glass showed a maximum at pH near 9, and it was zero at both ends of the pH region for all the initial concentrations studied. This fact is considered to confirm the theory of radiocolloid formation by the so-called adsorption method. The mechanism of radiocolloid formation was further discussed in detail. The formation of radiocolloids was explained by the adsorption of cobaltous ions on foreign particles, while the formation of insoluble cobaltous hydroxide was ruled out. It was estimated from these measurements that a very minute amount of foreign particles is sufficient to adsorb cobaltous ions and to change a large franction of the solute to radiocolloid. It was emphasized that such an estimation can be made only by the measurement of the adsorption, expressed by the unit of mol/cm2 as in the case of the present experiment, instead of the conventional unit of cpm/g or percent adsoiption.
Radical Conversions in γ-Irradiated 3-Methylpentane-Isobutene Systems
Authors: Tsuji Kozo , Okamura Seizo
Published: July 2006

Radical conversions in γ-irradiated 3-methylpentane-isobutene systems were observed by means of the electron spin resonance method after keeping the sample at −196°C for a few days, or by subjecting it to ultraviolet irradiation. One of the changes was caused by hydrogen atom abstraction from neighboring molecules by original free radicals. The other change was attributed to dissociation of the free radicals from 3-methylpentane by ultraviolet irradiation.
Nitrosyl Complexes of Bis(acetylacetone)-, and Bis(benzoylacetone)-ethylenediimine Cobalt(II)
Authors: Tamaki Motonori , Masuda Isao , Shinra Koichiro
Published: July 2006

Square, planar bis(acetylacetone)-, and bis(benzoylacetone)-etylenediimine-Co(II) chelates with a low-spin d7 electron structure yield nitrosyl complexes with the chelate : NO molar ratio of 1 : 1. On the basis of the IR spectra and the NMR spectra, and on the basis of molecular-weight determinations, these nitrosyls have been considered as being penta-coordinate cobalt complexes with square-pyramidal configuration. The nitrosyls are diamagnetic, indicating an electron-pairing bond between the central Co(II) and the NO molecule. The NO groups in these nitrosyls have been postulated to be predominantly neutral. In the electronic spectra, these penta-coordinate, diamagnetic Co(II) complexes show a characteristic absorption band at 18–20×103 cm−1 with logε\doteqdot3.
Pyrolysis-Gas Chromatographic Determination of Chlorine in Chlorine-Containing Synthetic Polymers
Authors: Tsuge Shin , Okumoto Tadaoki , Takeuchi Tsugio
Published: July 2006

A new, simple and rapid method for determining chlorine in chlorine-containing polymers was investigated by means of pyrolysis-gas chromatography. Hydrogen chloride evolved during the thermal degradation of the polymers was eliminated by a NaOH precut column, and only the organic compounds sensitive to flame ionization detector were separated to record the pyrograms. Chlorine content of the polymers was calculated from the relative yield of the degradation products using a theoretical equation deduced from the degradation mechanisms of the polymers. This unique method permits very rapid determination of chlorine with the use of about 0.1 mg of the sample without either the use of calibration curves or weighing of the samples.
A Partial Asymmetric Synthesis via a Cyclic Oxyphosphorane
Authors: Muroi Motoo , Inouye Yuzo , Ohno Minoru
Published: July 2006

A partial asymmetric synthesis was achieved in the carbon-carbon condensation which involved the reaction of (−)-menthyl pyruvate with trimethyl phosphite, followed by alkaline hydrolysis of the intermediate cyclic oxyphosphorane to yield (−)-(S:S)-2,3-dimethyltartaric acid. With knowledge of absolute configurations of both the chiral center and the predominant enantiomer of the product, an ex post facto interpretation of the steric course was made on the basis of relative steric stability of transition state conformations of the addition step of III to I.
Synthetic Studies of Cobalt Carbonyl by Noble Metal Catalysts. I. The Effects of the Form of Cobalt Feed and Noble Metal Catalysts
Authors: Usami Seiji , Kondo Takayoshi , Nishimura Kotaro , Koga Yuzo
Published: July 2006

A novel method of synthesizing cobalt carbonyl was investigated by using noble metal catalysts. It has been observed that the materials containing palladium, i. e., palladium black, palladium chloride, palladium acetylacetonate, bistriphenylphosphine dichloropalladium, and palladium-on-carriers, have a catalytic effect on the cobalt carbonylation reaction, and that palladium-on-carbon (Pd-C) is the most active catalyst. The reactivity of cobalt compounds in the cobalt carbonylation reaction catalyzed by noble metals increases in this order: CoSO4<<CoO\lesssimCo(OAc)2\lesssimCo-oleate<Co(OH)2. When the Pd-C catalyst is used, cobalt hydroxide reacts with synthesis gas of 150 kg/cm2 to give cobalt carbonyl almost quantitatively, even at from 50 to 55°C. The catalytic activities of noble metals were shown to be, in the order of decreasing activity: Pd>Au>Pt>>Ag. The effect of the catalyst concentration and the activity of noble-metal catalysts were also compared with those in the case of dicobalt octacarbonyl, as an autocatalyst.
Photolysis of Aromatic Oxime Benzoates
Authors: Okada Taiichi , Kawanisi Mituyosi , Nozaki Hitoshi
Published: July 2006

Irradiation of aromatic oxime benzoates, R1R2C=N–OCOPh, in benzene solution gives the corresponding azines, (R1R2C=N–)2, and ketones, R1R2C=O, along with PhCO2NH4. PhCO2H and Ph2 are also obtained in all cases. The reaction course can be explained by assuming a radical fission of excited R1R2C=N–OCOPh which gives radicals R1R2C=N· and ·OCOPh in the initial step. Sensitization experiment establishes the fact that a triplet state of the oxime benzoate is involved as a chemically reactive species.
Magnetic and Optical Properties of Aromatic Hydrocarbon Cation Radical Salts
Authors: Sato Yoichiro , Kinoshita Minoru , Sano Mizuka , Akamatu Hideo
Published: July 2006

Stable cation radical salts were prepared by oxidation of perylene, 9,10-diphenylanthracene, 9,10-dimethylanthracene, and 9,10-dichloranthracene with antimony pentachloride. Perylene perchlorate was also obtained in a stable form. From the temperature variations of their paramagnetic susceptibilities, the exchange coupling constants for these salts were found to increase in the sequence of above listing ranging from ∼0 to 8.5×10−2 eV. The absorption spectra of these solid compounds were compared with those observed with solutions. While the absorption bands of each salt in the visible region were found to correspond to those of the solution spectrum of the respective compound, an extra absorption band was observed in the near-infrared region for compounds with larger exchange coupling constants. The appearance of the new absorption band was reasonably ascribed to charge-transfer interaction between the radicals. These observations are considered to support further our previous suggestion that the magnitude of the exchange coupling constant obtained through magnetic measurements is basically determined by the stabilization energy due to the charger-transfer configurational interaction.
Anomalous Viscosity of Bitumen Solutions and the Agglomeration of “Molecules”
Authors: Inouye Katsuya , Tatsuta Junichi , Sakabe Tsutomu
Published: July 2006

The flow property of catechol and phenol solutions of 14 bitumen fractions was examined by means of a horizontal viscometer to compare with the molecular weight values of the fractions determined in each solvent. The catechol solutions showed Newtonian flow which corresponds to the homogeneous solutions containing molecules of a limited value of molecular weight. The molecular weight from phenol solutions varies with the fractions, and all fractions showed non-Newtonian (structural) viscosity. The experimental results indicated that bitumens in phenol agglomerate to different extent particular to each fraction. It was presumed that the stress destroys the agglomerated state to a monodisperse state, which is gradually recovered to the original state on standing. It was noted however that the unit particle (or molecule) composing each fraction is not identical in the apparent size in phenol, but varies with fractions.
The Radiolysis of Liquid Nitrogen Containing Hydrocarbons. I. Ethylene and Propylene
Authors: Oka Takefumi , Suda Yoshikazu , Sato Shin
Published: July 2006

The γ-radiolysis of liquid nitrogen containing ethylene and propylene has been investigated. As the nitrogenous products, hydrogen cyanide (0.18) and acetonitrile (0.04) were observed in the case of ethylene, and acetonitrile (0.12), in the case of propylene. The values in the parentheses are the G-values estimated on the basis of the energy absorbed by liquid nitrogen. In order to elucidate the mechanism of the reaction between nitrogen atoms and propylene, the mixture of C3H6 and C3D6 and the CD3CH=CHD compound have also been used as solutes. The acetonitrile obtained was mainly CH3CN and CD3CN in the former case, and CD3CN in the latter. These results suggest that a nitrogen atom produced in the system attacks the carbon atom in the middle of propylene and produces acetonitrile, leaving a methyl radical, the carbon atom in which was originally attached to the double bond.
Radiolysis of Methylcyclohexane. II. The Effect of Cumene on Hydrogen Formation from γ-Irradiated Methylcyclohexane
Authors: Kimura Toyoaki , Fueki Kenji , Kuri Zen-ichiro
Published: July 2006

The effect of cumene on the hydrogen yields from methylcyclohexane γ-irradiated at 100, 20, −72, −120 and −196°C has been investigated. Cumene did not compete with N2O for capturing electrons in methylcyclohexane and the yield of thermal H atoms in methylcyclohexane, determined by use of ethylene as an H atom scavenger, was smaller than the decrease in hydrogen yield in methylcyclohexane-cumene systems. Therefore, the decrease in hydrogen yield in methylcyclo-hexane-cumene systems can be ascribed mainly to positive charge transfer from methylcyclohexane to cumene. Further, the evidence of charge transfer from methylcyclohexane to cumene was found by the optical absorption method. The effect of cumene on the hydrogen yield from methylcyclohexane was similar in the temperature range from 100 to −196°C, especially at high cumene concentration. The effect of an electron scavenger at high concentrations was also examined with n-butyl chloride. In the present work, we have found that although the effect of a positive ion scavenger on the hydrogen yield from methylcyclohexane in the liquid state differs little from that in the glassy state, the effect of electron scavengers on the former differs considerably from that on the latter.
Group Interactions in Polyelectrolytes. II. Kinetics of Alkaline Hydrolysis of Polymethyl Acrylate
Authors: Kawabe Hiroshi , Yanagita Masaya
Published: July 2006

The second-order rate constant of the alkaline hydrolysis of polymethyl acrylate in an aqueous acetone solution decreases as the reaction proceeds. The plot of the logarithmic term of the second-order rate equation against the reaction time is divided into four lines; this suggests that the reaction proceeds in four steps. The rate equation of the reaction can be derived by assuming that the reactivity of ester groups is electrically affected mainly by a few neighboring hydrolyzed groups. The kinetic behavior is compared with the titration data of polyacrylic acid; the sets of data can be correlated through a simple equation containg two constants, k0, the intrinsic rate constant, and pK0, the intrinsic ionization constant.
The Electronic Structures of Glycine in the Isolated State and in Water
Authors: Imamura Akira , Fujita Hiroko , Nagata Chikayoshi
Published: July 2006

The electronic structures of glycine have been calculated for the dipolar-ion form and the neutral form by means of the CNDO method. The relative stability of both the dipolar-ion form and the neutral form in the gas state was reproduced by our calculation. The geometry of the glycine was also reproduced by the CNDO method, indicating the validity of our calculation. In addition, the relative stability of the two tautomeric forms of glycine was proved to be independent of its geometrical modifications. The experimental fact that the dipolar-ion form is more stable than the neutral form in an aqueous solution was well explained by the calculation of the interaction energy between the solute and the solvent.
Effect of Halogens and Oxygen on the Emission of Thermal Positive Ions from the Tungsten Surface
Authors: Kodera Kumasaburo , Kita Yoshifumi , Kusunoki Isao , Kishi Hiroshi , Sakiyama Atsuhiro
Published: July 2006

The effect of chlorine, bromine, and oxygen on the emission of thermal positive ions from tungsten filaments has been studied. When a tungsten filament is heated in a vacuum, positive ion emission is always observed, and it cannot be removed completely by flashing the filament at high temperatures. This background ion emission increases greatly in halogen or oxygen. Main positive ions are K+ and Na+. The increase cannot be explained by the increase of the work function of tungsten by the formation of adsorbed layer of halogen or oxygen atoms. It is ascertained that the tungsten surface reacts with these gases and the reaction products evaporate as neutral particles. As the reaction proceeds, tungsten surface is removed successively and alkali metal atoms in the bulk are exposed to the surface and contribute to the positive ion emission.
Investigations on the Kinetics and Mechanism of the Reduction of Mercuric Chloride by Malic Acid, Induced by Potassium Peroxodisulphate
Authors: Kumar Krishna , Saxena L K
Published: July 2006

The S2O82− induced reduction of mercuric chloride by malic acid has been studied by estimating the precipitated calomel. Kinetic measurements reveal the reduction rate to be independent of the acid concentration and first order in peroxodisulphate, but only to up an optimum concentration, whereafter further increase in inductor concentration decreases the reduction rate. A fractional order dependence in mercuric chloride concentration is encountered. The reaction is characterized by an initial of period induction. The initial rapid consumption of the acid results in lowering of the rate beyond a particular stage of the reaction. Increase of temperature and concentration of reactants is found to effect the period of induction. H+ ions and oxygen inhibit the reduction rate. Products identified are mainly calomel, carbon dioxide and malonic acid. A chain mechanism in which radical ion chain carriers participate, has been suggested.
The pNa Study of Sodium Alkyl Sulfates in Aqueous Solutions
Authors: Satake Iwao , Tahara Takashi , Matuura Ryohei
Published: July 2006

The counter-ion activity coefficient of sodium alkyl sulfate with chain length from C8 to C14 was determined in aqueous solutions and in the presence of added magnesium ion. The degree of association of sodium ion to the micelle (β) can be deduced from the concentration dependence of the counter-ion activity. The value of β so determined in the presence of magnesium ion was confirmed to decrease rapidly as the relative concentration of magnesium ion increases. The observed change of counter-ion activity with concentration was found to be interpreted in terms of a lameller micelle model.
A New Monoclinic Phase of Cerium Orthovanadate (CeVO4)
Authors: Yoshimura Masahiro , Sata Toshiyuki
Published: July 2006

A new monoclinic phase of cerium orthovanadate, CeVO4(H), was found during the course of oxidation of pseudo-perovskite CeVO3 below 400°C. It has been confirmed to crystallize in the huttonite-type structure (C2h5−P21⁄n), that of LaVO4. The lattice parameters were determined to be:

a 0=6.98Å, b0=7.22Å, c0=6.76Å, β=105°02′, V=328Å3 and Z=4.

This phase was metastable, and exothermally transformed into a known stable CeVO4 (tetragonal zircon-type, D4h19−I41⁄amd) above 400°C, releasing a small amount of oxygen. From magnetic, chemical and thermogravimetric analyses, the valences of cerium ion and vanadium ion in CeVO4-(H) seem to be tripositive and pentapositive respectively, but V4+ ion is mixed in zircon-type CeVO4; CeVO4(Z).
Solvent Effects in the Oxidation of Hydrocarbons. I. Chain Initiation by Azobisisobutyronitrile
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto
Published: July 2006

The effects of solvents on the rate of decomposition and the efficiency of radical production by AIBN were studied by measuring the rate of evolution of nitrogen from AIBN and the inhibition time in the oxidation of tetralin. The rates of decomposition of AIBN were larger in aromatic solvents than in aliphatic solvents. The efficiency of AIBN was found to depend more on the viscosity of the medium than on the polarity of the solvents. The requirements for the determination of the inhibition time are discussed.
Solvent Effects in the Oxidation of Hydrocarbons. II. Oxidations of Tetralin in Various Solvents
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto
Published: July 2006

The rates of oxidation of 1.47m tetralin in a variety of solvents at 70°C in the presence of 1.00×10−2m AIBN varied by a factor of 2.9, ranging from 6.39×10−6 mol/l/sec in n-decane to 1.84×10−5 mol/l/sec in nitromethane. The rate of oxidation was dependent on the composition of the solution as well as the kinds of solvents. It was found that the solvents affected the initiation step approximately as much as they affected the propagation and/or temination step. The rate of initiation by AIBN was mainly dependent on the viscosity of the medium, while that of propagation and termination was mainly determined by the dielectric constant of the medium. The correlation between log(kp⁄(2kt)1⁄2) and (D–1)/(2D+1) was discussed, where kp and kt are the rate constants for propagation and termination steps, respectively, and D is the dielectric constant of the medium, under conditions where the complication caused by the selective solvation could be excluded.
Stereochemical Studies of Monoterpene Compounds. VII. Conformational Study of 4-Hydroxymenthones by Temperature-dependent Circular Dichroism
Authors: Shishibori Tsuyoshi , Suga Takayuki , Watanabe Satoru , Matsuura Tamon
Published: July 2006

The conformational analysis of a stereoisomeric pair of 4-hydroxymenthones, (1R:4R)-(−)-4-hydroxymenthone (1) and (1R:4S)-(+)-4-hydroxyisomenthone (2), was made by means of temperature-dependent circular dichroism. It was demonstrated that α-hydroxyketone (1) exists in the conformational equilibrium: 1a\leftrightarrows1b; the conformer 1a exists predominantly in a nonpolar medium, whereas the conformer 1b is more stable than 1a in a polar medium. On the other hand, the other isomer, (2), exists preferentially in the state of the conformer 2b in either a polar or a nonpolar solvent. The results were interpreted in terms of the competition of the steric factor and intramolecular hydrogen-bonding.
α-Diketone Rearrangement. The Reaction of 1,2-Cyclohexanedione with Arginine and with Guanidine
Authors: Anzai Kentaro
Published: July 2006

A novel rearrangement reaction of cyclohexanedione, involving the loss of hydrogen in the product, is described. Cyclohexanedione and guanidine react in an alkaline solution to produce 2-amino-4-oxo-1,3-diazaspiro[4.4]non-1-ene (VIII) and l-hydroxy-3-amino-5-oxo-2,4-diazabicyclo-[4.3.0]non-2-ene (IX), the latter being an oxidized product. Similarly, cyclohexanedione reacts with arginine, producing, among other products, N5-(1-hydroxy-5-oxo-2,4-diazabicyclo[4.3.0]non-2-ylidene)-ornithine (III).
An MO-theoretical Interpretation of the Nature of Chemical Reactions. II. The Governing Principles
Authors: Fukui Kenichi , Fujimoto Hiroshi
Published: July 2006

The importance of the overlapping between the highest occupied (HO) molecular orbital (MO) of an electron donor and the lowest unoccupied (LU) MO of an electron acceptor in determining the favorable position and spatial direction of a chemical reaction is emphasized by setting up the following auxiliary principles: the principle of a positional parallelism between the chargetransfer and the bond-interchange, the principle of a narrowing of the inter-frontier energy-level separation, and the principle of a growing frontier density along the reaction path. These subprinciples work in a cooperative manner to enable us to arrive at this general governing principle: most of the chemical interactions are liable to occur at the position and in the direction where the overlapping of the HO and the LU of the respective reactants is at its maximum; in an electron-donating reactant, HO predominates in the overlapping interaction with the MO’s of the other reactant, whereas LU does so in an electron-accepting reactant; in the reactants which possess singly-occupied (SO) MO’s, these play the part of HO or of LU, or of both. These particular MO’s, HO, LU, and SO are “generalized frontier orbitals” in chemical reactions. This principle is applied to uni-centric reactions to give the orientation rule; if it is applied to multi-centric reactions, the stereoselection rule is obtained.