bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculation of the Chemical Shifts by the Semi-empirical SCF MO Method for All Valence-elctron Systems
Authors: Katô Hajime , Kato Hiroshi , Yonezawa Teijiro
Published: July 2006

The proton chemical shifts in the nuclear magnetic resonance spectra of CH4, C2H6, C2H4, H2CO, pyridine, and protonated pyridine were evaluated on the basis of Pople’s theory (J. Chem. Phys., 37, 53 (1962)) in which the shielding tensor is expressed in terms of the magnetic susceptibility of each atom in the molecule. The wave functions were obtained using a semi-empirical SCF MO method for valence-electron systems (Bull. Chem. Soc. Jap., 40, 536, 1017 (1967)). The 13C- and 14N- chemical shifts in the above compounds were calculated on the basis of the “Coupled Hartree-Fock perturbation theory.”
Chemical Reaction in Silent Electric Discharge. I. The Mechanism of Ozone Formation
Authors: Sugimitsu Hidetoshi , Asakura Ryozo , Okazaki Satiko , Suzuki Momotaro
Published: July 2006

The ozone formation reactions in the silent electric discharge starting from oxygen under atmospheric pressure and varied electric conditions were investigated. The results were found to be in line with the theory based on the postulates of reactional and electrical pattern, proposed earlier by authors. The reaction regime in discharge columns where the main reactions proceed is unusual. The duration of high frequency discharge which initiates the primary reactions is extremely short compared to the apparent duration of discharge of basic primary current. Thus, in the discharge columns a non-steady reaction regime is established. A rate theory is developed for the processes in silent discharge based on a non-steady state assumption, which is acceptable in view of the experimental results. The proposed pattern of processes is useful for obtaining more detailed mechanism of the reaction involved.
Crystal Structure of Bis(nitrosocyclohexane)
Authors: Tanimura Masamitsu , Kobori Kiyotomi , Kashiwagi Michio , Kinoshita Yukio
Published: July 2006

The crystal structure of bis(nitrosocyclohexane), (C6H11NO)2, has been determined by means of three-dimensional X-ray analysis by the photographic method. The crystal belongs to the triclinic space group P \bar1, with cell parameters, a=10.133 A, b=6.758 A, c=5.583 A, α=121°42′, β=96°50′, γ=78°06′. The unit cell contains one molecule. The nitrogen and oxygen atoms and the carbon atoms bound to nitroso-groups, CNO–O′N′C′, are almost coplanar, and the oxygen atoms take a trans configuration around the N–N′ bond. The cyclohexane ring takes a chair form and the nitrogen atom is bound to an equatorial bond. The CNO-O′N′C′ plane is twisted from the cyclohexane ring by 73°.
Radiotracer Studies on Adsorption of Surface Active Substance at Aqueous Surface. I. Accurate Measurement of Adsorption of Tritiated Sodium Dodecylsulfate
Authors: Tajima Kazuo , Muramatsu Mitsuo , Sasaki Tsunetaka
Published: July 2006

We carried out direct measurement of adsorbed amount at the air-solution interface to confirm the validity of the Gibbs adsorption equation by using radiochemically and surface chemically pure tritiated sodium dodecylsulfate (TSDS) and a sheet scintillation counter, which was developed for the purpose of counting β-rays of tritium in air. The adsorbed amount increased with increasing SDS concentration and showed the saturation values of 3.19×10−10 mol/cm2 in the concentration region from 3.2×10−3 to 14.4×10−3 mol/1000 g solution at 25°C. For the salt-free solution of ionic surfactant the Gibbs adsorption equation is confirmed to be valid for n=2 when activity in place of concentration is used. The equation of state for the ionic adsorbed film is further proposed. The cohesive pressure due to the attraction between hydrocarbon chains was given as a function of inverse molecular area.
The Magnetic Susceptibilities and ESR of Wurster’s Ions in Crystals
Authors: Tanaka Jiro , Inoue Motomichi , Mizuno Masagi , Horai Kazumi
Published: July 2006

The magnetic susceptibilities and the electron spin resonances of Wurster’s blue bromide, blue iodide, and red bromide have been measured over a wide temperature range. The results show that the paramagnetism of Wurster’s blue bromide above 210°K and of iodide can be explained by the linear Ising model, consistent with the crystal structure. Wurster’s blue bromide showed a deviation from the linear Ising model below 210°K; the dimer model is most appropriate for the explanation of the experimental data.

The intensities of the single ESR line are consistent with the results of the static susceptivility measurements. The hyperfine structures are not observed, perhaps because of the rapid movement of the triplet exciton. The magnetic results are explained in terms of the J-values, the origin of which are discussed on the basis of the interaction between the charge-transfer states and the singlet state. The values are resonably correlated with the interaction parameter, β, as estimated from the crystal structure and the electronic spectral measurements.
Steric Structure of l-Proline Oligopeptides. III. Calculated Absorption Spectra of l-Proline Oligopetides
Authors: Okabayashi Hirofumi , Isemura Toshizo
Published: July 2006

The electronic excited states in l-proline oligopeptides were derived from molecular-exciton theory. The dipole-dipole approximation was used in the calculation of transition energies. The calculated absorption spectra related to the conformation of l-proline oligopeptides were compared with observed ones. A satisfactory agreement between the calculated and observed results was obtained.
Base-catalyzed 1-3 Prototropic Isomerization of Cycloheptatrienes
Authors: Takahashi Kazuko , Yamamoto Hiroshi , Nozoe Tetsuo
Published: July 2006

The base-catalyzed proton migration (from the 7- to 2-position) and proton exchange (at the 7-position) of cycloheptatrienes carrying an electron-withdrawing group were studied in a medium of aqueous sodium hydroxide or alcoholic potassium hydroxide. The order of the effect of the various substituents upon the relative rates is approximately: CN>CONH2>COO−, Ph. The base-catalyzed prototropic isomerization proceeds through: i) the abstraction of a proton of the 7-position by the base, ii) the migration of the resulting carbanion to the allylic position (the rate-determining step), and iii) the recovery of a proton from the solvent. The kinetic study of the isomerization of 7-carboxycycloheptatriene (Ia) discloses the rate of the isomerization (k[the cycloheptatriene][base]) and the parameters (Ea=22.6 kcal/mol, ΔH\eweq=22.0 kcal/mol, ΔS\eweq=−15.4 e.u. at 60°). The structure of the cycloheptatrienyl anions formed as intermediates is discussed.
The Photosensitized Decomposition of Methyl Acetate at 77°K. A Kinetic Analysis of the Biphotonic Process
Authors: Mizutani Shigeru , Nakajima Yukihiko , Shimokoshi Kazuo , Sato Shin
Published: July 2006

The photosensitized decomposition of methyl acetate at 77°K has been investigated using an ESR technique. Naphthalene, α-naphthol, phenanthrene, anthracene, and benzophenone were used as sensitizers. When wavelengths longer than 2700Å were used, the formation of methyl radicals was observed except in the cases of anthracene and benzophenone. For the systems containing naphthalene, phenanthrene, and α-naphthol, the rate of the formation of methyl radicals was studied in detail and was found to obey the following relation:

R=αI^3/2C^1/2

Here, α is a proportional constant, I is the light intensity, and C is the solute concentration, which ranged from 5×10−5 to 2×10−3 mol l−1. Possible reaction mechanisms to explain the above relation were discussed; they include the biphotonic excitation of sensitizers, the triplet-triplet annihilation for the decay of the solute triplet, and the photolysis of the radicals produced in the photosensitization.
A Kinetic Investigation of Oxidation of Ethyl Methyl Ketone by Manganese(III) Sulphate
Authors: Banerji K K , Nath P , Bakore G V
Published: July 2006

The oxidation of ethyl methyl ketone with manganese(III) sulphate has been studied. The main product of oxidation is acetaldehyde. The reaction is first order with respect to each manganese(III) and the ketone. The rate of oxidation is independent of acidity and is not affected by changes in solvent composition. Addition of manganese(II) also does not affect the rate. The energy of activation, the entropy of activation and free energy of activation at 35°C have values 20.5 kcal/mol, −3.50 e.u. and 21.6 kcal/mol respectively. The rate of enolisation, measured by bromination method, is less than that of oxidation under similar conditions. A mechanism involving an attack directly on the ketone by manganese(III) sulphate-complex has been suggested.
Electronic Absorption Spectra of Zero-Valent Tris-(2,2′-bipyridine) Metal Complexes
Authors: Kaizu Youkoh , Yazaki Takanori , Torii Yasuo , Kobayashi Hiroshi
Published: July 2006

Electronic absorption spectra of zero-valent tris(2,2′-bipyridine) metal complexes of the first transition metals from titanium to cobalt have been studied. These spectra give a criterion to determine whether the central metal atom or the ligand is trapping the electrons furnished by reducing reagents upon syntheses of the complexes, if the absorption spectra of the coordinating negative ions are fairly free from the influence of the configuration interactions by the “ligand-metal” charge transfer excited states and/or by the “metal-ligand” ones. The vanadium complex is concluded as a complex of the metal atom in zero oxidation state and neutral bipyridine molecules, where the ‘metal-ligand’ charge transfer bands are observed. The iron- and the manganese-complexes are ionic complexes of the metal ion in a non-zero oxidation state and the negative ions of bipyridine, where the (π-π*) absorption bands of coordinating bipyridine negative ion are observed. On the basis of their spectral character, the complexes of the other transition metals might be assigned to be a hybrid of the two typical electron traps given above.
Chemical Effects Associated with the β-Decay Process. V. Kinetic Studies of the Chemical Behavior of the 144Pr Formed by the Decay of the 144Ce(III)-Ethylenediaminetetraacetate and 144Ce(III)-trans-1,2-Diaminocyclohexane-N,N′-tetraacetate
Authors: Shiokawa Takanobu , Kido Hiroaki , Omori Takashi
Published: July 2006

The chemical effects associated with the β−-decay of 144Ce(III)-aminopolycarboxylate complexes have been further investigated. The chemical behavior of 144Pr was analyzed kinetically on the basis of the isotopic exchange-reaction mechanism. The formation of the intermediate complex produced by an intramolecular electron transfer of the 144Pr(IV)-aminopolycarboxylate following the β−-decay of 144Ce(III) complex was also confirmed. In the ethylenediaminetetraacetate and trans-1,2-diaminocyclohexane-N,N′-tetraacetate systems, the values for the bond-rupture of the daughter complex ions are fairly much larger than in the diethylenetriaminepentaacetate system, suggesting that a kinetically-excited intermediate complex decomposes to a free ion to some extent.
The Copolymerization of Alkylene Glycol Nitrate Acrylates and Methacrylates
Authors: Moriya Masafumi , Yamashita Tadataka
Published: July 2006

The copolymerization of alkylene glycol nitrate acrylates (ANA) and methacrylates (ANMA) [M2] with styrene [M1] has been carried out at 60°C. The alkylene glycol mononitrates used were ethylene, propylene, and butylene glycol mononitrates, abbreviated as EGN, PGN, and BGN respectively. For their acrylates and methacrylates, the following abridged notations are used: ENA and ENMA, PNA and PNMA, and BNA and BNMA respectively. The monomer reactivity ratios, r1 and r2, and the Alfrey-Price Q2 and e2 values for ANA and ANMA were evaluated as follows: r1=0.48, r2=0.08, Q2=0.49, and e2=1.00 for ENA; r1=0.41, r2=0.20,Q2=0.69, and e2=0.78 for BNA; r1=0.35, r2=0.49, Q2=0.99, and e2=0.53 for ENMA; r1=0.36, r2=0.50, Q2=0.98, and e2=0.51 for PNMA and r1=0.37, r2=0.40, Q2=0.90, and e2=0.58 for BNMA. The polar and steric effects of the ester side chain containing the nitrate group were discussed. ANA was copolymerized with some other divinyl monomers, and the resulting crosslinked copolymer were subjected to the swelling test.
Multidentate Ligand Substitution Reactions. XI. Substitution Reactions of Nickel(II) Complexes of Diethylenetriamine and Ethylenediaminemonoacetic Acid with Diethylenetriaminepentaacetic Acid and of Nickel(II) Complexes of Diethylenetriamine and Ethylenediamine with Cyclohexane-1,2-diamine-N,N,N′,N′-tetraacetic Acid
Authors: Kodama Mutsuo , Fujii Yuki , Ueda Teiko
Published: July 2006

The kinetics of substitution reactions of nickel(II) complexes of diethylenetriamine and ethylenediaminemonoacetic acid with diethylenetriaminepentaacetic acid and those of diethylenetriamine and ethylenediamine with cyclohexane-1,2-diamine-N,N,N′,N′-tetraacetic acid were studied systematically by using the polarographic technique. All the reactions studied were found to be first-order with respect to the attacking group and also first-order with respect to the nickel(II) complex of diethylenetriamine, ethylenediamine, or ethylenediaminemonoacetic acid with a 1-to-1 composition. From a comparison of the relative rate constants determined experimentally with those calculated on the basis of a postulated reaction intermediate, the reaction mechanism was described in detail. All the reactions were concluded to proceed through the mixed ligand complex reaction intermediates which are characterized as having two nitrogen (amino) groups of displaced ethylenediamine, diethylenetriamine, or ethylenediaminemonoacetate ions bonded to the nickel(II) ion. This finding is contrary to the observation obtained by Rorabacher and Margerum from their kinetic study of the exchange reaction of the ethylenediaminetetraacetate anion with nickel(II) complexes of triethylenetetramine and tetraethylenepentamine.
Intramolecular Electron-transfer Reactions of Ethylenediaminetetra-acetatocobaltate(III) and Its Related Complexes in Solid State
Authors: Nagase Kenzo , Tanaka Nobuyuki
Published: July 2006

Electron transfer from a ligand to a central cobalt(III) in solid state was investigated by following the change of the valence state of coblat(III) to cobalt(II). The reaction was carried out in a vacuum as a function of sample amount, temperature and nature of a ligand and an outer-sphere cation. The electron-transfer reaction followed the first-order rate law. An outer-sphere cation had a slight effect on the reaction of the complex ion. The kinetic parameters obtained for potassium ethylenediaminetetraacetatocobaltate(III) (Ea=38 kcal/mol, A=1014) differed greatly from those for potassium propylenediaminetetraacetatocobaltate(III), potassium cyclohexanediaminetetraacetatocobaltate(III) and potassium trimethylenediaminetetraacetatocobaltate(III) (Ea\simeq 22 kcal/mol, A\simeq106). The kinetic behavior of the pentadentate complex, potassium hydrogen halogenoethylenediaminetetraacetatocobaltate(III), was compared with that of the hexadentate complex, potassium ethylenediaminetetraacetatocobaltate(III).
Trimethylenediamine Complexes. II. Some cis-trans Isomeric Pairs of Diacidobis(trimethylenediamine)cobalt(III) Complexes
Authors: Kawaguchi Hiroshi , Kawaguchi Shinichi
Published: July 2006

Isomeric pairs of cis- and trans-dinitro-, diisothiocyanato- and cyanosulfito-bis(trimethylenediamine)cobalt(III) complexes, and cis-nitronitritobis(trimethylenediamine)cobalt(III) nitrite were synthesized. Their electronic and infrared spectra were compared with each other to assign their structures. The cis-diisothiocyanatobis(trimethylenediamine)cobalt (III) complex was resolved into optically active isomers by means of potassium antimony(III) (+)-tartrate. The circular dichroism spectra of this dissymmetric complex were measured and discussed in relation to its absolute configuration which was recently determined by X-ray analysis.
Oxidative Coupling Reaction of Phenols with Dichromate
Authors: Tanaka Hiroo , Sakata Isao , Senju Ryoichi
Published: July 2006

On treatment in an aqueous solution with dichromate, p-cresol and creosol readily undergo nuclear oxidative coplig. The yields of dimeric and trimeric and trimeric cresols and of dimeric ketone are of the same order as the yields of the previously-recorded preparation by one-electron-transfer oxidants. When manganese sulfate is added, these yields are tripled. The probable mechanism of the coupling reaction of phenols with dichromate is discussed.
Photoreaction of Acetoacetate
Authors: Tada Masaru , Kokubo Tadayoshi , Sato Tadashi
Published: July 2006

Methyl acetoacetate was irradiated in the presence of cyclohexene to afford methyl 3-cyclohexyl-3-hydroxybutyrate (VIII), methyl 3-cyclohexenyl-3-hydroxybutyrate (IX), two oxetanes (Xa and Xb), and cyclohexene dimers. In contrast to acetylacetone, acetoacetate behaves as a saturated ketone rather than as an α,β-unsaturated ester on photoreaction. We concluded that the n-π* excitation of the enol-form of β-dicarbonyl compound is responsible for photo-cycloaddition, and no effective n–π* excitation is accesisble on irradiaron of the enol-form of acetoacetate, since the enol form of acetoacetate has its n–π* and π-π* absorptions in the same region.
A Study of Acyl Migration in Gallacetophenones
Authors: Kurosawa Kazu
Published: July 2006

3,4-Diacetoxy-2-hydroxyacetophenone, 3,4-dibenzoyloxy-2-hydroxyacetophenone and 3,4-bis(p-nitrobenzoyloxy)-2-hydroxyacetophenone gave corresponding 2,3-diacyl-4-methoxyacetophenones on treatment either with diazomethane or with dimethyl sulfate in the presence of potassium carbonate in acetone. Structure determination of the methylation product and also the methylation reaction of 3,4-dimethanesulfonyloxy-2-hydroxyacetophenone and 3,4-bis(p-toluenesulfonyloxy)-2-hydroxyacetophenone are reported.
Reaction of Olefin-Palladium(II) Chloride Complexes with Amides
Authors: Hirai Hidefumi , Sawai Hiroaki
Published: July 2006

Ethylene-palladium(II) chloride complex reacts with pyrrolidone and ε-caprolactam to produce N-vinylpyrrolidone and N-vinyl-ε-caprolactam, respectively. The yield of N-vinylpyrrolidone increases with increasing reaction temperature up to 120°C and decreases above 120°C owing to conversion of N-vinylpyrrolidone to an oily polymer through thermal polymerization. By addition of quinone, the yield increases remarkably at 25°C and 90°C. Pyrrolidone - palladium(II) chloride complex, which is too stable to react with ethylene at 25°C, reacts at 120°C to give N-vinylpyrrolidone. Open chain amides such as N-ethylacetamide, acetanilide and acetamide also react with ethylene - palladium(II) chloride complex, though the corresponding N-vinylamides cannot be obtained. The reaction of a styrene - palladium(II) chloride complex with pyrrolidone was also investigated.
Reactions of Haloferrocenes. III. The Reaction of Haloferrocenes with Copper(I) Benzenethiolate, Thiocyanate, Acetate, and Benzoate
Authors: Sato Masaru , Motoyama Izumi , Hata Kazuo
Published: July 2006

Iodoferrocene reacted with copper(I) benzenethiolate in boiling pyridine to give ferrocenyl phenyl sulfide in a quantitative yield. The reaction of iodoferrocene with copper(I) thiocyanate gave diferrocenyl disulfide. The behavior of copper(I) acetate and benzoate toward haloferrocene was found to be different from those of the other copper(I) salts: the reactions in boiling pyridine gave the corresponding ferrocenyl ester, together with a small quantity of ferrocene, while the reaction in boiling toluene produced biferrocenyl as the main product. The reaction mechanism of the ferrocenyl ester and biferrocenyl formations was discussed.
Studies on Fluorene Derivatives. XXVI. Radical Reactions in the Copyrolysis of Thermally-reactive Tribiphenylenepropanes
Authors: Suzuki Kazuo , Minabe Masahiro , Kubota Shozo , Isobe Taro
Published: July 2006

The pyrolyses of thermally-reactive tribiphenylenepropanes (mp 293°C (dec) or 257°C (dec)) in the presence of thermally-reactive 2,7,2′,7′,2″,7″-hexabromotribiphenylenepropane (mp 318–320°C (dec)) were investigated. Hydrocarbons, 2′,7′,2″,7″-tetrabromotribiphenylenepropane, 2,7-dibromo-9,9′-bifluorenyl, and -bifluorenylidene were obtained as pyrolysates from the respective thermal reactions, probably from intermolecular radical disproportionation reactions. In addition, 2,7,2′,7′-tetrabromo-9,9′-bifluorenyl, -bifluorenylidene, 2,7-dibromo-fluorene, and -fluorenone from hexabromotribiphenylenepropane, and 9,9′-bifluorenyl, -bifluorenylidene, fluorene, and fluorenone from tribiphenylenepropanes were formed by intramolecular reactions attributed to radical formation in the pyrolysis of each substrate. The pyrolyses of both tribiphenylenepropanes,. 9,9′-bifluorenyl and 2,7,2′,7′,2″,7″-hexabromotribiphenylenepropane, were observed in a differential scanning calorimeter. The thermogram of tribiphenylenepropane (mp 257°C) is similar to that of 9,9′-bifluorenyl; the first endothermic peak corresponds to the melting point, and the second, broad one seems to be due to the slow formation of 9,9′-bifluorenylidene from 9,9′-bifluorenyl by means of a dehydrogenation process. In the thermogram of tribiphenylenepropane (mp 293°C), the first endothermic peak is the melting point, while the second, small one is probably caused by the overlapping of exothermic and endothermic peaks due to radical reactions during the formation and pyrolysis of tribiphenylenepropane (257°C). The thermal homolyses of solid tribiphenylenepropane isomers or those in a silicon oil solution were examined by ESR, which confirmed the radical formation in the pyrolyses.
The Resolution and Rotations of trans-2-Aminocyclohexanecarboxylic Acids and Derivatives
Authors: Nohira Hiroyuki , Ehara Kenji , Miyashita Akira
Published: July 2006

Optically active trans-2-aminocyclohexanecarboxylic acids [(+)-1 and (−)-1] have been prepared by a preferential crystallization of racemic N-benzoyl trans-2-aminocyclohexanecarboxylic acid [(±)-2]. Active 2 have been used for preparation of such active trans-1,2-disubstituted cyclohexanes as (+)-, and (−)-ethyl trans-2-aminocyclohexanecarboxylate [(+)-3 and (−)-3], (+)-, and (−)-trans-2-aminocyclohexanemethanol [(+)-4 and (−)-4], (+)-trans-2-bromomethylcyclo-hexylamine hydrobromide [(+)-5], and (+)-trans-2-methylcyclohexylamine [(+)-6]. Amine-nitrous acid reaction of these cyclohexylamines to give the corresponding hydroxy compounds (7, 8, 9) has also been examined. It was confirmed that the signs of optical rotations of these hydroxy compounds are the same as those of the starting amines. It has been shown that observed molecular rotations of these active 1,2-disubstituted cyclohexanes are in agreement, in sign and order of magnitude, with those calculated following Brewster’s procedures presented in 1959 and in 1967.
Synthesis of Some New Fungicides
Authors: Choubey V N , Singh H
Published: July 2006

A number of 2-arylimino-3-aryl-4-thiazolidones and their 1,1-dioxides and 5-phenylazo derivatives have been prepared. The structure of these thiazolidones was confirmed by studying their hydrolysis products. Some of these thiazolidones were screened for their fungicidal activity against Aspergillus niger by agar-growth method and found to be more appropriately fungistatic and not fungicidal.
Studies of Ester-Containing Surfactants. Preparation and Properties of Sodium Sulfoalkyl Alkanoates
Authors: Hikota Takeshi
Published: July 2006

A series of sodium sulfoalkyl alkanoates, RCOO(CH2)jSO3Na, were prepared by means of sodium isethionate, propane sultone, and butane sultone with normal primary fatty acid composed of 10, 11, and 12 carbon atoms respectively. The effects of the position of the ester group on the Krafft point, the critical micelle concentration (CMC), the surface tention, and the other surface and colloidal properties of these surfactants were investigated. For a given number of carbon atoms, moving the ester group from the ionic head to a more central position in the hydrocarbon chain increased the CMC value and the calcium ion stalbility, and decreased the emulsion stability and the stability to hydrolysis. However, the wetting time was not strongly influenced by the position of the ester group in these compounds. The Krafft point of these surfactants decreased as the ester group was moved to a more central position.
Studies of the Aggregation of Dyes. The Scope of Application of the Maximum-slope Method
Authors: Hida Mitsuhiko , Sanuki Teruko
Published: July 2006

The maximum-slope method, previously suggested by one of the authors has proved to be more advantageously applied to the determination of the aggregation constant (Kn) and the degree of aggregation (n) in a dye solution than is Zanker’s method. Changes in the spectra of the aqueous or ethanolic solutions of Rhodamine 6G, 3,6-diaminoacridine and thionine were studied as their concentration increased by means of both the maximum-slope method and Zanker’s method. The aggregation characteristics obtained by these two methods were then compared with each other and discussed.
Magnetic Circular Dichroism of Iron Tetraphenylporphins
Authors: Kobayashi Hiroshi , Shimizu Masayuki , Fujita Ichiro
Published: July 2006

The magnetic circular dichroism of iron tetraphenylporphins was measured. Since the ground state of the open-shell iron porphin is degenerate and several charge-transfer excited states exist near the 1Q and 1B states, the A term as well as the B and C terms are very important for describing the MCD of the iron porphin, whereas the MCD at the 1Q and 1B bands, which arise from the pure degenerate (π,π*) excitations in D4h porphin assumed for zinc tetraphenylporphin, is ascribed to the A term. The MCD of carboxyhemoglobin, oxyhemoglobin and also deoxyhemologin was observed and compared with that of the synthesized iron porphins.
Aromatic Sulfonylation. I. Kinetics and Kinetic Isotope Effects in the Sulfonylation
Authors: Kobayashi Michio , Minato Hiroshi , Kohara Yoshio
Published: July 2006

p-Toluenesulfonylation of toluene, chlorobenzene and bromobenzene in the presence of aluminum chloride was investigated in methylene chloride at 0–20°C. The rate was equal to k3[TsCl][AlCl3][ArH]. Kinetic hydrogen isotope effects were found for p-deuteriotoluene (kH⁄kD=2.8) and p-deuteriochlorobenzene (kH⁄kD=1.98). Infrared studies indicated that not a sulfonyl cation but TsCl-AlCl3 complex was present in the medium. Substitution took place exclusively at para positions for halobenzenes, but 13.4% ortho and 86.6% para isomers were obtained for toluene. Partial rate factors for para positions were 52.5(PhCH3), 0.224(PhCl) and 0.164(PhBr). A plausible reaction mechanism was proposed, in which the abstraction of proton from the σ-complex was rate-determining.
Spreadability of Ovalbumin Monolayers at Air-water Interface
Authors: Ishii Toshio , Muramatsu Mitsuo
Published: July 2006

The spreading processes of ovalbumin have been studied quantitatively at air-water interface with either no additive or a small amount of hydrochloric acid for controlling subphase pH. Limiting area which is obtained by extrapolating force(F)-area(A) curve to F=0, increases with time, t, which has elapsed after the application of protein solution at the surface of subphase. Near the isoelectric point, the spreading processes are completed instantaneously to give the equilibrated value of limiting area which is found to be 0.83 m2/mg. The processes are much slower at both sides of the point, but the limiting area in equilibrium is found to be the same as in the case of isoelectric pH. It has also been shown that the processes are expressed in terms of two first-order reactions.
Electrical and Optical Behaviour of Tetrathionaphthacene at High Pressures
Authors: Shirotani Ichimin , Kawada Kaoru , Inokuchi Hiroo
Published: July 2006

The temperature dependence of the electrical resistance and the absorption spectra for tetrathionaphthacene (T.T.N.) have been studied at high pressure. It has been found that the intrinsic conduction level, which does not correspond to the observed optical transition, is located about 2 eV above the valence band. The red shift of absorption peaks with the pressure was much smaller than the contraction of the intrinsic band gap. The existence of the intrinsic conduction level is supported by the fact that the minimum of the photoemission yield arising from electron-pair production is located about 2 eV above the threshold point. The band gap of 0.4–0.62 eV previously observed seems to correspond to an acceptor level formed by chemical impurities.
Surface Properties of the System SiO2-Al2O3 prepared by the Hydrolysis of Metal Alkoxides
Authors: Murayama Hiroyoshi , Meguro Kenjiro
Published: July 2006

The mixtures of aluminum s-butoxide and silicon ethoxide in different molar ratio were hydrolyzed in aqueous alcohol. The precipitates were dried, and the growth and transformation of the crystals at calcination were estimated by X-ray diffractometry. The surface properties of the oxide powder were studied by means of the heats of immersion and the adsorption of nitrogen, water vapor and ammonia. The samples calcined at 500°C have surface areas 260–600 m2/g. Heats of immersion and surface hydrophilicity with respect to the composition, from pure silica gel to pure alumina, have a fairly good resemblance to each other, but this is not found between the heats of immersion and surface acidity.
Structural Studies of Antimony Tribromide and Its Molecular Complex with Benzene by Means of the 81Br Nuclear Quadrupole Resonance
Authors: Okuda Tsutomu , Terao Hiromitsu , Ege Osamu , Negita Hisao
Published: July 2006

The structures of α-antimony tribromide and its molecular complex with benzene 2SbBr3·C6H6 were investigated by studying the Zeeman effect on the nuclear quadrupole resonance (NQR) due to 81Br at room temperature. The bond angles, ∠Br-Sb-Br, of α-antimony tribromide in its solid state were found to be 94°14±4′, 94°31′±8′, and 98°27′±7′. The polar angles specifing the directions of the Sb-Br bonds with respect to the orthorhombic crystal axes are (60°0′±9′, 62°13′±7′), (59°10′±7′, −54°35′±8′), and (57°39′±17′, 180°0′±3′). These values are consistent with those of the X-ray analysis by Gushen et al. within about 1°. The asymmetry parameters at the three bromine atoms were 0.068±0.002, 0.049±0.002, and 0.080±0.004. On the other hand, the bond angles, ∠Br-Sb-Br, of the SbBr3 molecule in the complex 2SbBr3·C6H6 were found to be 92°24′±11′, 97°7′±14′, and 97°40′±6′. The crystal has a monoclinic symmetry, and the three Sb-Br bonds have directions making angles of 29°4′±21′, 76°26′±9′ and 63°33′±11′ relative to the b-axis. The asymmetry parameters at the three bromine atoms in the complex were 0.169±0.001, 0.063±0.002, and 0.094±0.002. The largest value of the asymmetry parameters seems to be the result mostly of the intermolecular bonding. From the coupling constants, the Sb-Br bond characteristics in antimony tribromide and its molecular complex, 2SbBr3·C6H6, are considered to be almost the same.
Studies of the Liquid-Liquid Partition Systems. VII. The Solvent Extraction of Mercury(II) Chloride, Bromide, Iodide and Thiocyanate with Some Organic Solvents
Authors: Sekine Tatsuya , Ishii Teruhiko
Published: July 2006

The liquid-liquid distribution of mercury(II) has been determined when the organic phase was benzene, hexane containing tributylphosphate(TBP), methylisobutylketone(MIBK), or nitrobenzene, and when the aqueous phase was 0.5m sodium per chlorate containing chloride, bromide, iodide, or thiocyanate ions. The stability constants for the mercury(II) complexes in the aqueous phase and the distribution constants for the extractable complexes were determined by a graphic analysis of the distribution data, which were measured as a function of the ligand concentration. It was concluded that the stability constants determined from the present results agree almost entirely with the previous values and that the only extracted species into benzene and hexane containing TBP is the non-charged complex (HgX2, where X− is the ligand) in all cases, whereas those extracted into MIBK or nitrobenzene include not only the non-charged but also the charged species (HgX3− and sometimes HgX42−) except in the case of the chloride system. The distribution ratio in the hexane-TBP system was further determined by changing the TBP concentration in the hexane phase, and the equilibrium constants for the adduct formation between the HgX2 species and TBP molecules were determined. Finally, some discussion was made of the relation between the distribution behavior of the mercury(II) complexes and the natures of the ligands and the solvents.
Absorption Spectra of Gaseous Benzo[g,h,i]perylene and Coronene
Authors: Aihara Jun-ichi , Ohno Koichi , Inokuchi Hiroo
Published: July 2006

The gas-phase spectra of typical polycyclic aromatic hydrocarbons benzo[g,h,i]perylene and coronene, were measured. These data can be used as criteria for the solvent shifts and the molecular excitons.
Direct Determination of Charge Transfer Energy
Authors: Aihara Jun-ichi , Tsuda Motoyuki , Inokuchi Hiroo
Published: July 2006

The absorption spectrum of the gaseous anthracene - chloranil complex was measured. The Coulomb energy contributing to the charge-transfer transition was determined to be 3.03 eV. The polarization energy for the transition was 0.17 eV in an n-heptane solution.
Ion-Solvent Interaction of Tetraalkylammonium and Some Common Ions in N-Methylformamide from Viscosity Data
Authors: Rastogi Pushti Prakash
Published: July 2006

Solute-solvent interaction of tetraalkylammonium iodides (R4NI) and some common electrolytes has been studied in N-methylformamide (NMF) from the viscosity point of view. From the obtained results it has been concluded that common electrolytes like LiCl, KI, CsI are net structure promoters while R4NI salts are net structure breakers in this solvent.
Ionic Equilibria in Mixed Solvents. V. Intermediates of Polymerization of Aluminum Ion in a 0.2 Mole Fraction Dioxane-Water Mixture
Authors: Ohtaki Hitoshi
Published: July 2006

Formation of highly polymerized hydroxo-complexes of aluminum ions proceeded so slowly in a dioxane-water mixture that less polymerized intermediates were detected by means of the usual emf titration techniques. The titrations were performed at 25° in solutions of total aluminum concentrations of 0.00500, 0.0100, 0.0200, 0.0399, 0.0400 and 0.0798m in a 0.2 mol fraction (55.01 % w/w) dioxane-water mixture containing 3m LiClO4 as an ionic medium. The emf data obtained can be explained in terms of the formation Al2(OH)24+ (log*β2,2=−6.95±0.07) and Al2(OH)33+ (log*β3,2=−10.02±0.03) assuming equilibrium conditions. It was observed that these complexes proceed further slowly to form highly polymerized complexes.
Photon-Activation Analysis for Iodine by Using Cesium as the Internal-Reference Element
Authors: Tsai Hui-Tuh , Kato Toyoaki , Oka Yoshinaga
Published: July 2006

The internal-reference method proposed previously has been applied to the determination of iodine by photon-activation analysis, using cesium as the internal-reference element. The present method is based on the measurement of the 126I, 124I and 123I activities produced by the neutron-emitting reactions in iodine, and on the comparison of these activities with that of 130I coming from cesium by the (γ, 2pn) reaction. A lithium-drifted germanium diode with a sensitive volume of 36 cm3 was used as the detector. The yields of various photonuclear reactions in both elements have also been examined as a function of the bremsstrahlung maximum energies up to 65 MeV. A series of synthetic mixtures of iodine-cesium with known weight ratios has been used to check the sensitivity and the accuracy of this method. We found that we could determine amounts of iodine down to 0.2 μg under the present experimental conditions.
Alkoxysilanes. V. The Preparation of Polyalkyl(aryl) Silicates
Authors: Abe Yoshimoto , Takeuchi Takeo , Kijima Ichiro
Published: July 2006

Silicon-containing novel polymers, polyalkyl(aryl) silicates (Remark: Graphics omitted.) and (Remark: Graphics omitted.), were prepared by the reaction of diaminosilanes with aliphatic or aromatic diols. The products were a white powder (fused at about 300°C), a highly viscous liquid, or a glassy solid; these products were soluble in common organic solvents, but insoluble in methanol. The results of the molecular-weight determination by the vapour-pressure method indicated that some of polymers had a molecular weight of 5000 or 6000. A study of the thermal stability of the polymers by means of TGA and DTA analysis made clear that the polymers with the aryloxy group in the molecular main chain were remarkably more stable than those with the alkoxy group. The former indicated a weight loss of about 50% at 350–400°C. An investigation of the TGA curve and thermal decomposition products allowed us to discuss the probable process for the degradation of the polymers. The reaction of the diaminosilanes with 1,4-butanediol afforded distillable products rather than the expected polymers; these products were identified as being cyclic alkoxysilanes.
Synthese der Epiminozucker
Authors: Ichimura Kunihiro
Published: July 2006

Two-step conversion of aldehydes to 2-monosubstituted aziridines has been extended to sugar derivatives. Treating O,O′-isopropylidene-d-glyceraldehyde with benzenesulfonyl chloride and sodium cyanide, 2-benzenesulfonyloxy-3,4-isopropylidenedioxybutyronitrile is obtained as a mixture of the diastereomers in a good yield, and is converted to the corresponding ketalaziridine, 2-(1,2-isopropylidenedioxyethyl)aziridine, by the reduction with lithium aluminum hydride. When the partially racemized isopropylideneglyceraldehyde is used, the diastereomers obtained are successfully separated by the fractional recrystallization. Each diastereomeric α-sulfonyloxynitrile is reduced by lithium aluminum hydride to afford the ketalaziridine, which is p-nitrobenzoylated and rearranged to the derivative of 1,3,4-trihydroxy-2-amino-butane by means of sodium iodide. Analogously, 3-O-benzyl-1,2-O-isopropylidene-α-d-glucopentodialdo-1,4-furanose was converted to two urononitriles, 3-O-benzyl-5-O-benzenesulfonyl-1,2-O-isopropylidene-α-d-gluco-furanurononitrile and the epimeric β-l-idofuranurononitrile. The reduction of the former yielded 5,6-epimino-5,6-dideoxy-β-l-idofuranose.
Studies of the Thiocarbonyl Compounds. I. Syntheses and Thermal Rearrangement of O,S-Diaryl Dithiocarbonates
Authors: Araki Yoshiaki
Published: July 2006

Various O,S-diaryl dithiocarbonates with the general formula of p-X–C6H4–S–C(=S)–O–C6H4–Y-p (I) were prepared. When these substances were kept at an elevated temperature, they rearranged smoothly to S,S-diaryl dithiocarbonates of this general formula: p-X–C6H4–S–C(=O)–S–C6H4-Y-p (II). Kinetic studies showed that the rearrangement followed fairly good first-order kinetics. The rate constants in diphenyl ether at 200°C increased in the order: Y=OCH3<CH3<H<Cl<COCH3<CN<NO2. The entropies of activation were negative, and no crossover products were obtained. A four-membered cyclic structure can be suggested as the transition state for this rearrangement.
Bromodenitrogenation of N2-Benzoylarginine Ethyl Ester with N-Bromosuccinimide
Authors: Anzai Kentaro
Published: July 2006

N 2-benzoylarginine ethyl ester (II) reacted with N-bromosuccinimide at pH’s above 7 to yield, as the main product, N2-benzoyl-N5-cyanoornithine ethyl ester (VII), as well as N3,N6-bis(4-benzamido-4-ethoxycarbonylbutyl)s-tetrazine-3,6-diimine (VIII), N,N′-di(4-benzamido-4-ethoxycarbonylbutyl)urea (IX), and N2-benzoylcitrulline ethyl ester (X) as minor products. On acid hydrolysis, VII afforded the following amino acids: ornithine (III), citrulline (IV), N6-[(4-amino-4-carboxybutyl)-carbamoyl]arginine (V), and N,N′-di(4-amino-4-carboxybutyl)urea (VI). The mechanism of these reactions was also discussed.
Stereochemical Studies of Monoterpene Compounds. VIII. The Stereochemistry of Dihydro-β-campholenolactone and 1,2-Campholide
Authors: Hirata Toshifumi , Suga Takayuki , Matsuura Tamon
Published: July 2006

The stereochemistry of (+)-dihydro-β-campholenolactone (II) and (−)-1,2-campholide (III) was clarified to be Ila and IVc, respectively, by a combination of nuclear magnetic resonance, optical rotatory dispersion and circular dichroism measurements.
Alkylation of Sodium Dithionite
Authors: Matsuo Kuniko , Kobayashi Michio , Minato Hiroshi
Published: July 2006

Reaction between sodium dithionite and triethyloxonium fluoborate under nitrogen yielded an unstable oil capable of absorbing oxygen. When it was washed and distilled under reduced pressure, ethyl ethanesulfinate was obtained. The reaction between sodium dithionite and alkyl iodides in water or in DMSO yielded dialkyl sulfone. The reaction between sodium ethanesulfinate and triethyloxonium fluoborate in dichloromethane yielded an oily mixture which was 89% ethyl ethanesulfinate and 11% diethyl sulfone. The reaction of alkyl iodides with an excess of sodium dithionite yielded, besides a sulfone, sodium alkanesulfonate, not sodium alkanesulfinate. Mechanisms of these reactions were discussed.
The Adsorption of Polyvinyl Pyrrolidone on Silver Iodide Surfaces
Authors: Sugiura Masaaki
Published: July 2006

Adsorption isotherms for four kinds of polyvinyl pyrrolidone (PVP), having different molecular weights, on the sol particles and the powder of silver iodide at 25°C were obtained. Further, the adsorption of PVP on the sol particles was investigated by means of the electrophoresis method. All of the PVP materials give approximate adsorption isotherms of the Langmuir type, at least up to the PVP concentration of 0.4 g/l At higher concentrations, the amounts of PVP adsorbed gradually increase with the increase in the PVP concentration. The effect of the molecular weight on the PVP adsorption is not observed except for the lowest-molecular-weight material, which displays a lower adsorption. The tendency for the ζ-potential of the sol particles to increase with an increase in the PVP concentration almost coincides with that of the amount of PVP adsorbed.
Sound Velocity in Aqueous Non-Electrolyte Solutions in Relation to Water Structure
Authors: Nomoto Otohiko , Endo Harumi
Published: July 2006

An acoustic interferometer is employed to obtain the variation of sound velocity with concentration and temperature in hexamethylenetetramine (HMT), urea, thiourea, acetamide and N,N-dimethylformamide (DMF) and their aqueous solutions. The plot of velocity of aqueous solutions of these organic substances against temperature gives parabolic curves similar to one for pure water. In these curves, the maximum height of sound velocity is higher than that for pure water and the temperature at maximum point is lower than for water. The curves of sound velocity vs. concentration at various temperatures show values of maximum velocity at intermediate concentrations. The maximum value decreases with increasing temperature and finally disappears in some cases. Results show that the velocity dependency on temperature and concentration are qualitatively determined by the relative concentration of non-associated water to cluster. The sound velocity of acetamide and DMF is 1404.4 m/sec (65°C) and 1478.8 m/sec (20°C), respectively, and shows negative temperature coefficients of −2.68 m/sec/deg and −3.90 m/sec/deg, respectively.
Studies on Triplet Energy Transfer by Means of an Emission-Absorption Flash Technique. I. Reversible Energy Transfer between Xanthene Dyes and Anthracenes
Authors: Kikuchi Koichi , Kokubun Hiroshi , Koizumi Masao
Published: July 2006

Choosing eosin and erythrosin as donor and anthracene and 9-methylanthracene as acceptor, we have kinetically investigated the triplet energy transfer process by flash technique involving emission measurement. In these systems the differences of T-levels of donor and acceptor are of the order of kT at most, and it was anticipated that a reversible energy transfer would occur. It has been established that it actually occurs in eosin-anthracene and erythrosin-anthracene, and very likely occurs in erythrosin-9-methylanthracene. Furthermore, it has been found that in the first two systems the energy transfer rate for the process, donor→acceptor is about half that for the process, acceptor→ donor. This means that the rate in the present systems is determined by some other factor than the triplet level. Discussions have been given on the model for energy transfer.
Methane Formation in the Radiolysis of Neopentane and Isooctane
Authors: Iida Shuichi , Yugeta Rei , Sato Shin
Published: July 2006

The formation of methane and hydrogen in the γ-radiolysis of neopentane and isooctane has been studied in the presence of an electron scavenger (N2O) and/or a radical scavenger (styrene). The G-value of nitrogen from neopentane solutions of nitrous oxide was found to be about twice the sum of the decrease in the G-values of methane and hydrogen. From isooctane solutions, G(N2) was more than three times the sum of the decrease in G(H2) and G(CH4). This can be interpreted on the assumption that a significant part of the neutralization of isooctane ions with electrons induces the fragmentation into C4-hydrocarbons. It was also found that a part of the methane formed (0.9 G in neopentane and 0.2 G in isooctane) was not produced by the reactions of ions or methyl radicals, but by a “molecular” process, probably the decomposition of the highly-excited states.
Photochromic Reaction of N-Nitroso-N-alkylaniline in the Aqueous Solution—A Contribution to the Photochemistry of Nitrosamine
Authors: Hoshino Mikio , Kokubun Hiroshi , Koizumi Masao
Published: July 2006

It has been found that the aqueous solution of N-nitroso-N-methylaniline when irradiated by 253.7 nm shows photochromism. The unstable photoproduct reconverts to the original compound photochemically as well as thermally. The quantum yields for the forward and backward reaction are respectively 0.23 and 0.58. N-Nitroso-N-ethylaniline also reacts in the similar way. In the alcoholic solutions, different types of reaction occurred; in the absence of oxygen the reaction is mainly the formation of N-methylaniline. It has been suggested that the present photochromism is due to the cis-trans isomerization.
Spectrophotometric Determination of Mercury(II) by Solvent Extraction with Variamine Blue B
Authors: Tsubouchi Masahiro
Published: July 2006

A new rapid, sensitive and selective method is proposed for the spectrophotometric determination of a trace of mercury (II) by solvent extraction. The method is based on the formation of an ion-pair complex between the tribromo-mercury(II) complex anion and the dyestuff cation obtained by oxidation of variamine blue B. The optimum pH range for the color reaction is 2.5–4. The blue complex can be extracted into nitrobenzene and has a maximum absorption at 605 mμ in the organic solvent. Beer’s law holds in the range 3.2×10−6−2.2×10−5  m of mercury(II) in the aqueous layer before the extraction, with a molar absorptivity of 4.03×104 mol−1cm−1  l at 605 mμ. The color reaction is instantaneous and the complex remains stable 15 mintes in the nitrobenzene layer. Of the 22 cations and 11 anions examined, tin(II), tin(IV), antimony (III), iodide, cyanide, and thiocyanate showed serious interferences.