bluuebunny/crossref_metadata_2025 huggingface dataset:
Catalytic Decomposition of the Excess Reagent in the Spectrophotometric Determination of Copper(II) with o,o′-Dihydroxyazo Compounds
Authors: Sugawara Masao , Rokugawa Yuh’ichi , Kambara Tomihito
Published: July 2006

A simple and sensitive spectrophotometric method for determination of copper(II) is described. It is based on the reaction of copper(II) with Hydroxynaphthol Blue in the weakly alkaline medium and the decomposition of the unconsumed reagent which shows an intense absorption at the wavelength, 555 nm, of the maximum absorbance of the copper(II) complex. Beer’s law is obeyed over the range 0.13–1.27 ppm copper with the molar absorption coefficient of ε555=3.01×104 dm3 mol−1 cm−1 (Sandell’s sensitivity 2.11×10−3 μg/cm2). A fairly large number of common ions except for nickel(II) do not interfere.
The Crystal and Molecular Structure of the Aquabis(cyclo-l-histidyl-l-histidylato)dicopper(II) Perchlorate Hydrate [H2O Cu2(C12H13N6O2)2](ClO4)2·3.5H2O
Authors: Kojima Yoshitane , Hirotsu Ken , Matsumoto Keiji
Published: July 2006

The crystal structure of the title compound has been determined by a three-dimensional X-ray structure analysis, using 4563 counter intensity data. The crystals are monoclinic, with a=22.97(2), b=15.89(1), c=10.00(1) Å, β=100.1(1)°, space group P21, and Z=4. The structure was solved by the Patterson and Fourier technique and was refined by the block-diagonal least-squares method to R=0.061. The unit cell contains two crystallographically independent complex cations, the structure of which are very similar to each other. The complex cation is dimeric; there are two Cu atoms, and each of the two cyclo-l-histidyl-l-histidylato ligands bridges two metal atoms. Except for the aqua ligand, the main body of the complex has an approximate twofold axis which passes through the two metal atoms and relates the ligands to each other. The two Gu atoms have different coordination geometries. One Gu atom has a flattened tetrahedral coordination by 4N atoms, whereas the other is surrounded by 2N and 3O atoms and is intermediate between the square pyramid and the trigonal bipyramid.
A Re-investigation of the Dimer ESR Spectra in Several Quadridentate Schiff Base Complexes of Copper(II)
Authors: Chikira Makoto , Yokoi Hiroshi
Published: July 2006

The angle between the g⁄⁄ axis and the copper-copper axis in most parallel planar dimers of the quadridentate salicylaldehyde Schiff base complexes of copper(II) in toluene or xylene has been reconfirmed to be not ≈35°, but ≈17°, by a computer simulation of the dimer ESR spectra at both the K and X-bands. In order to remedy the shortcomings of the so-called point-dipole approximation generally used in the simulation, a delocalization model, in which the delocalization of each unpaired electron on the copper atom and its surrounding four ligand atoms is explicitly taken into consideration, has been discussed in some detail. The delocalization effect has been proven to be highly significant in estimating dimeric structures reliably. An application of this model to the structural estimation of several dimers in solutions has also been made.
Preparation and Properties of Pd(II) and Pt(II) Complexes of N-Picolinoyl-S,S-tetramethylenesulfilimine, N-Trimethyl-ammoniopicolinamidate, and Related Ylides
Authors: Kise Hideo , End\={o} Hiroyuki , Sen\={o} Manabu
Published: July 2006

The reactions of N-picolinoyl-S,S-tetramethylenesulrilimine and N-trimethylammoniopicolinamidate with dichlorobis(benzonitrile)palladium(II) and dipotassium tetrachloroplatinate(II) afforded chelate complexes of formula MCl2[Ylide]. The structures of the complexes were examined by IR and NMR spectroscopy, and determined as mononuclear complexes with ligands coordinated through two nitrogen atoms. A reverse relationship between pKa values of the ylides and C=O stretching band frequency shifts on complex formation was found, and the nature of the coordination via ylidic nitrogen was discussed in terms of σ- and π-character of the ligands in the chelate complexes and several related bis-ylide complexes.
The Consitution of NaPO3–GeO2 Melts
Authors: Watanabe Makoto , Ito Masao , Sato Shoji , Yamada Tamotsu
Published: July 2006

The glassy and crystalline thermal products were prepared by heating a mixture of sodium phosphate glass and germanium dioxide with P/Ge ratios of 1.0–300 at 1000 °C for 3 h in a platinum crucible, and by then rapidly quenching the resulting melt. The thermal products with P/Ge ratios larger than 50 were glassy. The products with P/Ge ratios smaller than 30 were a mixture of glassy and crystalline substances, and the quantity of the glassy substance in the mixture increased with an increase in the P/Ge ratio. The crystalline substance was insoluble in water. From the results of the distribution and the average chain length of the condensed phosphates present in the glassy thermal products, it was concluded that the glass has P–O–Ge linkages and that the most reasonable chemical structure of the glass is (Remark: Graphics omitted.). The colorimetric determination of the phosphorus and germanium contained in the crystalline thermal product showed that the P/Ge ratio of the crystalline substance is 1.3. The value of the P/Ge ratio corresponds to that of Ge3(PO4)4.
Photochemistry of Heterocyclic Compounds. VII. Photochemical Reaction of 2,5-Diphenyl-1,3,4-oxadiazole with Benzo[b]thiophenes
Authors: Oe K\={o}ji , Tashiro Masashi , Tsuge Otohiko
Published: July 2006

Irradiation of 2,5-diphenyloxadiazole 1 with benzothiophene 6a gives 3-benzoylbenzothiophene 7, its benzoylhydrazone 8, and/or the oxadiazepine 9; the yields depended on the nature of solvents. With benzophenone as a sensitizer, the photochemical reaction of 1 with 6a forms the [2+2] cycloadduct 12. It is found that 9 is photochemically dissociated to 1 and 6a. In the case of 2-methylbenzothiophene 6b, 3-benzoyl-2-methylbenzothiophene benzoylhydrazone 18 is formed, and with benzophenone as a sensitizer the [2+2] cycloadduct 19 is obtained. In the absence or presence of benzophenone, however, irradiation of 1 with 3-methylbenzothiophene 6c gives the [2+2] cycloadduct 20. The photochemical reaction of 1 with 6a or 6b in the presence of iodine gives the corresponding 3-benzoylbenzothiophene, 7 or 21, and benzoylhydrazone, 8 or 18, respectively. In the case of 6c, however, the [2+2] cycloadduct 23 is formed, together with 2-benzoyl-3-methylbenzothiophene 22. Mechanistic considerations of these reactions are also described.
A New Synthesis of Flavones by the Reaction of 2-Phenyl-2H-1-benzopyrans with Potassium Permanganate
Authors: Ashihara Yoshihiro , Nagata Yasuyuki , Kurosawa Kazu
Published: July 2006

The oxidation often 2-phenyl-2H-1-benzopyrans with potassium permanganate in acetone has been found to give the corresponding flavones in 8–73% yields. The reaction mechanism is discussed on the basis of the substituent effect and the oxidations of related compounds.
The Reaction of N-Imidoylsulfimides with Carbon Disulfide
Authors: Yoshida Hiroshi , Ogata Tsuyoshi , Inokawa Saburo
Published: July 2006

The reaction of S,S-diphenyl- and S,S-dimethyl-N-imidoylsulfimides (1 and 2) with carbon disulfide was studied. 1 yielded nitrile, isothiocyanate, diphenyl sulfide, and sulfur, whereas 2 gave N-thiocarbonyl-S,S-dimethylsulfimide together with isothiocyanate. Kinetic studies indicate that the reaction proceeds via a [2+2]cycloaddition mechnism, as is shown by the small effects of the solvents and the substitutent on the rate.
1,3-Dipolar Cycloadditions to Bicyclic Olefins. II. The Effects of Non-aromatic Polar Solvents on the exo/endo Product Ratios in 1,3-Dipolar Cycloadditions to Norbornadienes
Authors: Taniguchi Hisaji , Yoshida Yoshihiro , Imoto Eiji
Published: July 2006

The exo/endo product ratios for three types of 1,3-dipolar cycloadditions of phenylglyoxylonitrile oxide(1) to 2,3-bis(methoxycarbonyl)norbornadiene(2a), norbornadiene, and 2,3-dicyanonorbornadiene decrease with increasing ET value of the non-aromatic polar solvent used. The exo/endo ratio in the reaction of 1 with 2a is larger than unity, but the value of ΔHexo\eweq−ΔHendo\eweq is nevertheless positive. This phenomenon is attributed to the relatively large positive value of ΔSexo\eweq−ΔSendo\eweq, that is, ΔGexo\eweq−ΔGendo\eweq<0 at ordinary temperatures. On the basis of these results, the conditions, under which the exo/endo ratio in the reaction of 1 with 2a is smaller than unity, were determined. The results can be reasonably explained by the assumption that the dipole moment of the endo-form in the transition state is greater than that of the exo-form.
Solid-Phase Syntheses of Glu20Ala20Phe and Ala20Glu20Phe by the Step-by-step Coupling of Dipeptide and Tetrapeptide
Authors: Takahashi Sho
Published: July 2006

Glu20Ala20Phe, (I), and Ala20Glu20Phe, (II), were synthesized by the step-by-step coupling of Nα-t-butoxycarbonyl (BOC-) derivatives of Ala–Ala and (γ-benzyl–Glu)4 to phenylalanyl-1% crosslinked polystyrene resin using dicyclohexylcarbodiimide. The products were cleaved from the resin with hydrogen bromide in acetic acid and purified by gel filtration, followed by DEAE-cellulose chromatography, with yields of approximately 10% for both of the hentetracontapeptides. The optical purities of the glutamic acid and alanine incorporated in the pep tides, I and II, were estimated as 1 and 5% respectively from the analysis of the diastereomeric mixture of dipeptides derived from the reaction between the total acid hydrolyzate of I or II with the N-hydroxysucinimidyl ester of BOC–l-Leu.
Water Vapor Affinity of Potassium Bromide Coated with Potassium Oleate
Authors: Chikazawa Masatoshi , Yamamoto Fujio , Saita Eiko , Kaiho Mamoru , Kanazawa Takafumi
Published: July 2006

The amounts of adsorbed water and the isosteric heats for water vapor adsorption on fine crystals of KBr treated with various amounts of potassium oleate (KOI) were measured. In the adsorption isotherm of untreated KBr, a slight stepped rise of the amount adsorbed was observed, and this step is considered to be due to the two-dimensional condensation of water molecules adsorbed on the uniform surfaces of KBr particles. The monolayer capacity, determined from the adsorption isotherm of KBr by the point B method, agreed with the value calculated according to an adsorptive structure based on the two assumptions that all the surfaces of the KBr particles consist of (100) planes and that one water molecule is adsorbed per regularly distributed Br− site.

A small amount of pre-adsorbed KOI was recognized to prevent the water vapor adsorption on KBr, and conversely, this effect disappeared with increasing KOI content while the hygroscopicity of the sample increased markedly. This abnormal increase in the adsorbed amount suggests that the adsorbed water molecules penetrate into the multilayer films of KOI on the KBr.
Chemical Studies on Tuberactinomycin. XII. Syntheses and Antimicrobial Activities of [Ala3, Ala4]-, [Ala3]-, and [Ala4]-Tuberactinomycin O
Authors: Teshima Tadashi , Nomoto Shinya , Wakamiya Tateaki , Shiba Tetsuo
Published: July 2006

Total syntheses of [Ala3, Ala4]-, [Ala3]-, and [Ala4]-tuberactinomycin O corresponding to deoxy analogs of natural antibiotic tuberactinomycin O were achieved for the purpose of elucidation of relationship between chemical structure and biological activity. Cyclization of the pentapeptide intermediates at two different positions was investigated. Minimum inhibitory concentrations of the synthetic analogs against Mycobacterium or Corynebacterium indicated that both hydroxy groups of two serine residues of tuberactinomycins are not required for antibacterial activity, nor participated to drug-resistancy of bacilli. These analogs were found to have the same conformations in solution as those of natural antibiotic from the results of NMR, ORD, and CD measurements.
Silyl Radicals. XV. Stereochemical Course of Chlorine Abstraction by 1-Methyl-4-t-butyl-1-silacyclohexyl Radicals from Polychloroalkane
Authors: Sakurai Hideki , Murakami Masashi
Published: July 2006

The isomerically pure cis and trans 1-methyl-4-t-butyl-1-silacyclohexane were subjected to the free radical chlorination with carbon tetrachloride in the presence of a catalytic amount of benzoyl peroxide under UV irradiation at 0 °C, affording the corresponding chlorosilanes with retention of configuration. With less reactive polyhalocarbons, however, less stereospecific products were obtained. A mechanism that inversion of silyl radicals competes with chlorine abstraction is proposed. Relative rates of each reaction were analyzed with a steadystate assumption.
Hetera-p-carbophanes. IX. Effect of the Chain-Length of Alkoxyl Groups on the Barrier to Internal Rotation of Dialkoxybenzene Rings in Dialkoxydioxodioxa[n]paracyclophanes
Authors: Sakamoto Kazuhiko , Oki Michinori
Published: July 2006

Dioxodioxa[n]paracyclophanes which carry two methoxyl, ethoxyl, or propoxyl groups at the aromatic rings were prepared by condensation of α,ω-diols with corresponding 2,5-dialkoxy-1,4-phenylenediacetyl dichlorides under high dilution conditions. Dynamic 1H NMR spectra of these compounds show that barriers to internal rotation of the dialkoxybenzene rings are affected by the chain-length of the alkoxyl groups; the longer the chain length, the higher the barrier.
Electrophilic Sulfides(II) as a Novel Catalyst. V. Structure, Nucleophilicity, and Steric Compression of Stabilized Sulfur Ylides as Observed by 13C-NMR Spectroscopy
Authors: Matsuyama Haruo , Minato Hiroshi , Kobayashi Michio
Published: July 2006

13C chemical shifts and 13C–H spin coupling constants (179.7 Hz) of the ylide carbons of two dialkylsulfonium phenacylides show that the ylide carbons are basically sp2. Large upfield shifts (−9.5–−11.8 ppm) of carbonyl carbon signals (δC 181.7 and 179.2) of the ylides from those of the corresponding salts (δC 191.2 and 191.0) suggest significant contribution of a betaine structure. The 13C-NMR spectrum of methylisopropylsulfonium phenacylide showed two non-equivalent methyl signals (δC 17.9 and 18.4) for the isopropyl group. Steric γ-effects on ylide carbon chemical shifts were observed with several alkylsulfonium bis(methoxycarbonyl)methylides and trialkylsulfonium salts.
Annihilation of the Catalytic Activity in Butene Isomerization of Porous Vycor Glass by Washing with EDTA Aqueous Solution
Authors: Hirai Shoji , Morikawa Akira , Ishinaga Yoshio , Otsuka Kiyoshi , Wada Yuji
Published: July 2006

The catalytic activity of porous Vycor glass in the isomerization of butenes was eliminated by washing the glass with EDTA aqueous solution, though the contents of Al and Zr in the glass remained unchanged. Destruction by decationation of active sites of silica-alumina character has been suggested.
Effect of a Polymer Ligand on Oxidation of Thiophenol Catalyzed by Cobaloximes
Authors: Nishikawa Hiroshi , Kasai Masanori , Terada Ei-ichi , Tsuchida Eishun
Published: July 2006

The oxidation mechanism of thiophenol catalyzed by cobaloximes was deduced by spectroscopic measurement of the oxidation rate at various concentrations of the reactants, the reaction being a Michaelis-Menten type reaction. Addition of polymer ligands such as poly(4-vinylpyridine) and 4-vinylpyridine-styrene copolymer, stabilizing the intermediate similar to a Michaelis complex, resulted in an increase in the oxidation rate under low substrate concentration.
Oxidation Activity and Acid-base Properties of Mixed Oxide Catalysts Containing Titania. II. The TiO2–V2O5–P2O5 System
Authors: Ai Mamoru
Published: July 2006

The acidity and basicity of a series of TiO2–V2O5–P2O5(atomic ratio Ti : V : P=9 : 1 : x) catalysts with different P2O5 contents (x=0–18), were measured by studying the adsorption of the basic and acidic molecules in the gas phase, using both the static and pulse methods. TiO2–V2O5(V/Ti=1/9) is rather basic, but this catalyst can be modified from basic to acidic by the introduction of P2O5. The vapor-phase oxidation of butadiene and 1-butene, which were chosen as electron-donor-type reactants, and that of acetic acid, as an acidic reactant, were carried out in the presence of an excess of air, and then the relationship between the catalytic behavior and the acid-base properties was investigated. The results support an earlier proposal that the activity and selectivity in mild oxidation can be interpreted in terms of the acid-base properties of the catalyst and the reactant.
The Interaction of Bovine Plasma Albumin with Cationic Detergent. Studies by Binding Isotherm, Optical Rotation and Difference Spectrum
Authors: Hiramatsu Koichi , Ueda Chiaki , Iwata Koji , Arikawa Kinichi , Aoki Koichiro
Published: July 2006

Binding isotherms were determined at pH 6.9 for systems of bovine plasma albumin (BPA) and cationic detergents at 25°C and 5 °C. Detergents used were: hexadecyltrimethylammonium bromide (HTAB), tetradecyltrimethylammonium bromide (TTAB), dodecyltrimethylammonium bromide (DTAB) and decyltrimethylammonium bromide (DeTAB). Binding affinity of the cationic detergent to BPA increased with the increase in the carbon number of the detergent, and with the increase in temperature. The first five detergent ions were bound to BPA statistically at 25 °C, and succeeding detergent ions were bound cooperatively. Thermodynamic parameters indicated that the statistical binding was caused mainly by the hydrophobic bonding. Measurements of −[α]233 and −[α]313 at pH 5.2 revealed that the conformation of BPA changed when it complexed with the cationic detergent. The conformation of BPA changed slightly when 5–8 HTAB or TTAB’s were bound, and a second large conformational change occurred when 15–20 of these detergent ions were bound. DTAB and DeTAB caused only the first conformational change. Thus HTAB and TTAB are stronger unfolders of BPA than DTAB and DeTAB. The UV difference spectrum of the complex BPA–TTAB showed a red shift of the peak of Try residue (e.g. 292 nm), being in contrast to the blue shift of the same peak in the complex BPA–sodium dodecyl sulfate. It is suggested that BPA is unfolded, at least, in the NH2 terminal half by binding with cationic detergent.
Molecular Structure of Molybdenum Tetrafluoride Oxide Studied by Gas Electron Diffraction
Authors: Iijima Kinya
Published: July 2006

The molecular structure of molybdenum tetrafluoride oxide was determined to be square-pyramidal by a sector-microphotometer method of gas electron diffraction. The following molecular parameters were obtained by a least-squares method: rg(Mo–F)=1.836±0.003 Å, rg(Mo–O)=1.650±0.007 Å, and rg(F···F(s))=2.522±0.005 Å. The molecular structure is similar to those of WCl4O and MoCl4O, but significantly different from those of XeF4O and IF5. The molecular intensities calculated using the TFD or RHFS phase angle for molybdenum atom were in disagreement with the observed ones.
An INDO-UHF Molecular Orbital Study of the Conformations and Electronic Structures of Some σ-Type Radicals
Authors: Ohkubo Katsutoshi , Sato Hiroyuki
Published: July 2006

The equilibrium geometric parameters determined for XC=Y radicals (HC=O, CH3C=O, NH2C=O, and HC=CH2) are not characterized by their bond lengths but by their X–C–Y angles, which are wide compared with the angles in their parent molecules (XHC=Y). The %s character of the a orbitals on the C atom in XHC=Y was found to be conserved in the %s character and the s-orbital spin density of the same atom in XC=Y radicals: there are linear relationships between them. Some notable features of the unpaired-electron distribution on the frameworks of XC=Y radicals are also discussed in connection with the electronic properties of the σ radicals.
Determination of Chlorine in Rocks, Soils and Organic Materials by Heating Powdered Sample in Strong Phosphoric Acid, and Some Additional Investigations on the Related Reactions
Authors: Terada Kikuo , Hirakawa Saburo , Kiba Toshiyasu
Published: July 2006

The decomposition of several salts in strong phosphoric acid (SPA) was examined. These halides were decomposed and hydrogen halides evolved by heating the samples with SPA at various temperatures. Based on these data an adequate reagent was chosen for the efficient separation of various elements which can form volatile halides. The recommended distillation condition was applied to determine the chlorine content in solid samples, such as rocks, soils or some organic materials. The sample was heated in an SPA medium and a distillate of hydrogen chloride was absorbed in a sodium hydroxide solution. The solution was subjected to volumetric analysis with a silver nitrate solution for chlorine in the range of 10−2 to 10−4 mol and to spectrophotometric determination with mercury thiocyanate for elements less than 10−4 mol. Furthermore, from the results of X-ray diffraction measurements of the original and the SPA-treated samples, it was confirmed that the main crystal structure of a rock sample could be decomposed by heating with SPA. The chlorine analysis was performed for Japan Geological Survey standard rocks, JG-1 and JB-1, and a synthesized complex compound.
Thermal Behavior of the Clathrate Compounds of the Type M(diam)M′(CN)4·2C6H6
Authors: Ohyama Jun-ichi , Tsuchiya Ryokichi , Uehara Akira , Kyuno Eishin
Published: July 2006

The thermal behavior of the guest molecule trapped in the clathrate compounds, M(diam)M′(CN)4·2C6H6, where M and M′ are bivalent metal atoms and diam is two ammonia molecules or one molecule of diamine, and the structural changes of the host lattice upon heating were studied by means of derivatographic and isothermal measurements. In Cd(NH3)2Ni(CN)4·2C6H6, the elimination of guest benzene molecules was found to proceed in two steps. X-Ray powder diffraction patterns suggest that the skeleton of the host is preserved, at least during the first liberation of 1 mol of benzene, but the skeleton collapses after the complete liberation of benzene and ammonia. The host skeleton of Cd(en)Ni(CN)4·2C6H6 was preserved till the liberation of 75% of benzene. The activation energies were a little larger than the respective enthalpy changes. The replacement of M′=Ni by Pd or of M′=Cd by Hg in the clathrate compounds, if M and diamine are the same, scarcely changes the activation energy for the liberation of the guest molecule, but the replacement of M and diamine by other ones somewhat changes the activation energy.
Reaction of Dimethyl Sulfoxide–Trifluoroacetic Anhydride with Anilines, Phenols, and Thiophenols
Authors: Hiraki Yuji , Kamiya Masahiro , Tanikaga Rikuhei , Ono Noboru , Kaji Aritsune
Published: July 2006

The reaction of dimethyl sulfoxide–trifluoroacetic anhydride complex with anilines, phenols, and thiophenols was studied, and the following results were obtained. (1) The yields of a methylthiomethylated product were improved with anilines. The reaction proceeded without significant amount of tar, the unreacted anilines being easily recovered. (2) Selective ortho-methylthiomethylation took place with phenols in good yields at lower temperature, para-methylthiomethylation occurring at higher temperature. (3) Methylthiomethylation took place with thiophenols on a sulfur atom of thiophenol at room temperature in a simple process.
Photolysis in Rigid Matrixes at Low Temperatures. An Intermediate of Photo-dehydrobromination
Authors: Hirayama Satoshi
Published: July 2006

The intermediate of the photo-dehydrobromination of 9-(α-bromopropionyl)anthracene (I) to yield 9-anthryl vinyl ketone (IV) was detected by its electronic spectrum upon photolysis in polar solvent matrixes at 77 K. Approximately 80% of the initial photo-products is trapped as the intermediate. The remainder is observed as the final product IV formed directly from I. The intermediate is stable only below ca. 83 K in EPA. Above this temperature, it decomposes rapidly to form IV. No intermediate was detected for this reaction in the non-polar solvent matrixes at 77 K. Instead, a conformational change of IV with temperature was noticed. Based on the temperature and solvent effects on the stability of the intermediate, a loose structure where a hydrogen bromide is almost completely eliminated via a concerted mechanism is postulated for the intermediate. This is supported by the evidence that the main electrochemical reduction product of I is only 9-propionylanthracene. The temperature effects on the other photochemical reactions of I are also discussed in relation to the allowed molecular motions in rigid matrixes.
Electronic States of the 4,4′-Dinitrobiphenyl–Benzidine Complex
Authors: Tanaka Masashi
Published: July 2006

The charge transfer complex composed of 4,4′-dinitrobiphenyl and benzidine was studied by measuring and analyzing the UV crystalline spectra. The deep coloration of this complex was found to be due to the charge transfer bands appearing at 21000 and 25000 cm−1, while the long axes of the component molecules are known to be perpendicular to each other.
The Halogenation and Nitration of the Optical Active Isomer of the α-Acetylacetonato(triethylenetetramine)cobalt(III) Complex
Authors: Kuroda Kashiro , Yamaguchi Kazumi , Yamaoka Noriko
Published: July 2006

The methylidyne hydrogen of the coordinated acetylacetonate ion in (+)d-α-acetylacetonato(triethylenetetramine)cobalt(III) perchlorate has been replaced with halogens and with a nitro group with a complete retention of the configuration. The order of the molar rotations of the complexes has been found to be: acac-<Clacac-<Bracac-<Iacac-complex and acac-\simeqO2Nacac-complex.
Geometrical Isomerism of 2,4-Dinitrophenylhydrazones of Some Pyruvic Esters
Authors: Nashima Takeo , Ishibashi Fumihide , Iwamoto Masayuki , Aihara Yoko , Anzai Sumiko , Yamanoze Goro
Published: July 2006

Visible, IR, and PMR spectra of 2,4-dinitrophenylhydrazones (DNPH) of some pyruvic esters were studied. It is suggested that each α-isomer with a higher Rf-value involves an intramolecular hydrogen bond between the imino hydrogen and the ester carbonyl group, to which the Z-structure is assigned. The E-structure is assigned to each β-isomer with a lower Rf-value.
Acyl Cyanide. IV. The Reduction of Phenyl-substituted Carbamoyl Cyanides with Metal Hydrides
Authors: Oku Akira , Inoue Jiro , Ueda Hiroyuki , Mashio Fujio
Published: July 2006

The reaction of phenylcarbamoyl cyanide with LiAlH4 or NaBH4 gave glycine anilide, N-phenylethylenediamine, and N-methylaniline. With the latter hydride, 4-amino-1,3-diphenyl-2-imidazolidinone was also formed. The reduction of diphenylcarbamoyl cyanide with LiAlH4 gave N-methyldiphenylamine as the only reduction product.
Gaseous Products from the Plasma Decomposition of Isomeric Xylenes
Authors: Venugopalan M , Scott Thomas W
Published: July 2006

The formation of methane and ethane on decomposition of the isomeric xylenes in Siemens-type discharges has been investigated. With increasing voltage the methane yield decreased, while the ethane yield increased; the C2H6/CH4 mole ratios increased continuously but varied in the order ortho>meta>para.
Reaction of Recoil 35S Atoms with Organic Compounds. Insertion Reaction of Recoil 35S Atoms into the C–H and the C–C Bond
Authors: Niisawa Kazuhiro , Taki Ko
Published: July 2006

The insertion reactions of recoil sulfur atoms produced by the nuclear transformation of 35Cl(n,p)35S process into the C–H bond of benzothiazole and the C–C bond of 2-methylbenzothiazole have been examined. It has been found that the C–H insertion is a little easier than the C–C insertion by the energetic sulfur atoms, and that in thermal reaction the water used as a solvent seems to have some role in producing the C–H insertion product.
He I Photoelectron Spectra of Ethylene Carbonate and Related Compounds
Authors: Jinno Masafumi , Watanabe Iwao , Yokoyama Yu , Ikeda Shigero
Published: July 2006

He I photoelectron spectra of ethylene carbonate, propylene carbonate, γ-butyrolactone, β-propiolactone and vinylene carbonate have been investigated. Assignments of an oxygen lone pair and nonbonding π orbitals have been made by means of analysis of vibrational structures and molecular orbital calculation. Many vibrational structures could be assigned to appropriate vibrational modes of the corresponding neutral molecules from a comparison with infrared and Raman spectra. Correlation among the orbital energies of the compounds is discussed.
The Sol-Gel Transition of Sodium Deoxycholate Solutions under High Pressures
Authors: Sugihara Gohsuke , Ueda Toshiaki , Kaneshina Shoji , Tanaka Mitsuru
Published: July 2006

The effect of pressure on the sol-gel transition of sodium deoxycholate (SDC) solutions was investigated by the electric conductivity method up to 2000 atm in the temperature range from 10 to 65 °C. The gelation of SDC solutions is effected more easily at lower temperatures, at higher pressures, and at higher concentrations of SDC. The changes in the volume (Δ\barV(αβ)), the enthalpy (Δ\barH(αβ)), and the entropy (Δ\barS(αβ)) of gelation were calculated thermodynamically. The values for Δ\barV(αβ), Δ\barH(αβ), and Δ\barS(αβ) are all negative under the conditions of this experiment. Therefore, it is concluded that the gel formation of SDC is attributable to intermolecular hydrogen bonds.
The Microwave Spectrum, Structure, Quadrupole Coupling Constants, and Barrier to Internal Rotation of Methyldichlorosilane
Authors: Endo Kunihiko , Takeo Harutoshi , Matsumura Chi
Published: July 2006

The microwave spectra of the 35Cl2, 35Cl37Cl, and 37Cl2 isotopic species of CH3SiHCl2 have been investigated in the frequency region from 12 to 40 GHz. The rotational constants and centrifugal distortion constants have been determined and were used to calculate the structure of the molecule. The structural parameters determined are:

& r(Si–C)=1.850 Å, ∠C–Si–Cl=109.8°,

& r(Si–Cl)=2.040 Å, ∠Cl–Si–Cl=108.8°.

A few high-J R-branch transitions are split into doublets because of the methyl internal rotation. These splittings give a barrier to internal rotation of 1.69±0.05 kcal/mol. An analysis of the 35Cl2 quadrupole splittings leads to quadrupole coupling constants of χaa=−19.1±0.3 MHz, χbb=5.4±1.3 MHz, χcc=13.7±1.4 MHz, χbond=−41.2±2.0 MHz, and ηbond=0.16±0.03.
The cis-trans Isomerization of 2-Butenes Caused by Sulfur Dioxide Adsorbed on Porous Vycor Glass. The Contribution of the Charge-transfer Complex
Authors: Otsuka Kiyoshi , Eshima Kiyoshi , Morikawa Akira
Published: July 2006

Sulfur dioxide adsorbed on porous Vycor glass enhances the cis-trans isomerization of 2-butenes selectively, but it poisons the double-bond migration. The correlation between the cis-trans isomerization and the sulfur dioxide–cis-2-butene charge-transfer complex observed on the glass were studied under various pressures of the reactants. The kinetic data of the reaction were well explained by the reaction mechanism in which the isomerization occurs via the addition and elimination of 2-butene molecules at the terminal of the polysulfone formed from sulfur dioxide and cis-2-butene in the adsorbed layer. It has been suggested that the copolymerization is initiated through the charge-transfer complex polarized in the strong electrostatic field of the exposed aluminum ions contained in the glass.
Charge-transfer Character in the Intramolecular Hydrogen Bond: Electronic Structures and Spectra of Hydrogen Maleate Anion and Related Molecules
Authors: Morita Hiroshi , Fuke Kiyokazu , Nagakura Saburo
Published: July 2006

Ultraviolet absorption spectra were measured with aqueous solutions of maleic acid (H2M) at various pH values and in concentrated sulfuric acid solutions. With the aid of the theoretical calculations of electronic structures by the modified CNDO-CI method, relatively strong bands observed at 193.5 nm for H2M, at 210.0 nm for the hydrogen maleate anion (HM−), and at 202.8 and ≈230 nm for the dinegative ion (M2−) are assigned to the π–π* transition bands. Special attention was paid to the charge-transfer (CT) character (pertinent to the strong intramolecular hydrogen bond) in the excited states of HM−. Configuration analysis of the wave functions revealed us that the first π–π* band of HM− covered by the much stronger 210 nm band is rich in the CT character pertinent to the hydrogen bond.
The Influence of a Co-ion on the Potential of a Liquid Ion-exchnger Membrane Electrode
Authors: Jyo Akinori , Fukamachi Kazumi , Koga Wataru , Ishibashi Nobuhiko
Published: July 2006

The potential of a liquid ion-exchanger membrane electrode was affected by a co-ion, i.e., an ionic species with the same charge sign as the ion-exchange site in the liquid membrane, when the co-ion in the sample was lipophilic. An aspect of the influence or interference of the co-ion on the response of the electrode is clarified theoretically, based on the three-region concept of the membrane potential. Theoretical predictions of the co-ion interference are illustrated by the measurement of potentials of a nitrate-sensitive nitrobenzene membrane electrode for sample solutions containing sodium nitrate, tetramethylammonium nitrate and the like. The co-ion interference became more important for increased extractability of the co-ion in the nitrobenzene-water system, specifically the order is Rb+<Cs+<(CH3)4N+, and for a decrease in the concentration of the ion-exchanger in the membrane. Go-ion interference appeared for high concentration levels of the ion to be determined and produced a negative error in the activity measurement. The results are in good agreement with the theoretical predictions.
Chromium(III) Complexes with Amino Acids. II. Chromium(III) Complexes with l-α-Amino Acids
Authors: Oki Hisaya
Published: July 2006

As chromium(III) complexes with l-α-amino acids (alanine, aminobutyric acid, norvaline, norleucine, valine, isoleucine and leucine), [Cr(ala)3], (+)[Cr(am-but)3], [Cr(OH)(am-but)2]2, (+) and (−)[Cr(norval)3], (−)[Cr(norleu)3], [Cr(OH)(norleu)2]2, [Cr(val)2(val–O)(NH3)], (+)[Cr(isoleu)3], [Cr(isoleu)2(isoleu–O)(NH3)], [Cr(OH)(isoleu)2]2, (+) and (−)[Cr(leu)3], and [Cr(OH)(leu)2]2 were prepared by the matrix method in solid state, and [Cr(ala)3], [Cr(am-but)3], [Cr(OH)(am-but)2]2, (−)[Cr(norval)3], [Cr(OH)(norval)2]2, (−)[Cr(norleu)3], [Cr(OH)(norleu)2]2, (+)[Cr(val)3], [Cr(val)2(val–O)(NH3)], [Cr(OH)(val)2]2, (+)[Cr(isoleu)3], [Cr(OH)(isoleu)2]2, and a mixture of diasteroisomers of [Cr(leu)3] were obtained by the usual method in solution. Some differences in the formation of the tris-type and hydroxo-dimer complexes appeared between the two methods. Especially, in the solid reaction, some complexes gave diastereoisomers with optically-active counter structures depending upon the kind of solvents used for preparation. All tris-type chromium(III) complexes with l-α-amino acids were of fac-structure.
The O-Alkylation of Phenols by Esters. II. The Steric Hindrance and Electronic Effect in the O-Alkylation of Phenol by Esters
Authors: Kito Taketoshi , Yamamoto Kazumune , Hirao Ichiro
Published: July 2006

The steric hindrance in the O-alkylation of PhOK by alkyl acetate (PhOK+AcOR→PhOR+AcOK) was examined by means of competitive reactions. As a result, the following sequence of the reactivities of alkyl acetates was obtained: CH3>>C2H5>n-C3H7\gtrsimn-C4H9>s-C4H9>i-C3H7\gtrsimi-C4H9>t-C4H9 and n-C4H9>n-C5H11>i-C5H11. The electronic effect in the O-alkylation was also examined by means of the competitive reaction of p-substituted (CH3 or CH3O) methyl benzoate and methyl benzoate with PhOK. The reactivity decreases in the following order: C6H5COOMe>p-CH3C6H4COOMe>p-CH3OC6H4COOMe. Therefore, it was concluded that the rate-determining step is the attack of the phenoxide anion on the carbon atom of the methyl group.
Tautomerism of 4-Pyridones
Authors: Besso Hiromichi , Imafuku Kimiaki , Matsumura Hisashi
Published: July 2006

The tautomeric constants, Kt, of several 4-pyridones were determined by measurement of pKa values. For 2-substituted 5-methoxy-4-pyridones, the Kt values were correlated to the substituent constants σ, the equation logkt=2.98+2.93σm−6.18σo being obtained.
Investigation of the Reaction of Metal–Nitrosyl Complexes. I. New Nitrosolysis Reaction of Cycloalkanones Using Sodium Pentacyanonitrosylferrate(II)
Authors: Ishigaki Akira , Oue Masatoshi , Matsushita Yoshikazu , Masuda Isao , Shono Toshiyuki
Published: July 2006

Cycloalkanones reacted with sodium pentacyanonitrosylferrate(II) (NP) to give red-brown or red-violet colored complexes under an alkaline condition. The solvolysis of the complexes gave ω-(hydroxyimino)alkanoic acids under a hot alkaline condition and gave ω-cyanoalkanoic acids or their esters in an acidic condition in good yields. These Products correspond to nitrosolysis products of cycloalkanones. The reaction mechanism was invesigated by use of 15N labeled NP. The complex was formed initially by an electrophilic attack of the nitrosyl ligand of NP to the active methylene of the cycloalkanone. Then a C–C bond cleavage of the resulting ligand, 2-(hydroxyimino) cycloalkanone, occurred by an action of the solvent species under the influence of the central ferrate ion. The solvolysis of the ligand occurred through Beckmann fission by an action of the acid in the coordination sphere.
Odor and Volatile Compounds in Liquid Swine Manure. I. Carboxylic Acids and Phenols
Authors: Yasuhara Akio , Fuwa Kei-ichiro
Published: July 2006

Seventeen carboxylic acids and four phenol compounds were isolated from liquid swine manure by steam distillation and identified by gas chromatography-mass spectrometry. The major components are butyric, isovaleric, benzoic, phenylacetic acids, and p-cresol. The only carboxylic acid fraction has the same odor as liquid acidic swine manure. The odor of the phenols is rather pleasant and sweetish. The butyric, isovaleric, and phenylacetic acids have a very strong malodor, while the odor of phenylacetic acid is identical with that of liquid acidic swine manure.
The Reaction of Phenolic Compounds with Isoprenoids. VIII. The o-Isoprenylation of Phenols in the Presence of Metallic Sodium
Authors: Yamada Shigetoshi , Ono Futara , Katagiri Takao , Tanaka Juntaro
Published: July 2006

Phenols (phenol, hydroquinone, resorcinol, and o-cresol) reacted with prenyl halides (3-methyl-2-buteny chloride and geranyl chloride) in the presence of an alkali metal (Na) in ether. In these reactions, phenols with the corresponding prenyl group at the ortho position were obtained selectively.
An Effect of Heat-treatment on the Activity of Titanium Dioxide Film Electrodes for Photo-sensitized Oxidation of Water
Authors: Tamura Hideo , Yoneyama Hiroshi , Iwakura Chiaki , Murai Takaaki
Published: July 2006

When an anodic oxide film of titanium and a pyroly tic ally prepared TiO2 film were subjected to a heat-treatment in an argon atmosphere, their activities for photo-sensitized oxidation of water were improved.
Transfer-free Energy Aspect on the Keto-enol Tautomerization Rate of Benzoylacetone in Water-Dimethyl Sulfoxide Mixtures
Authors: Watarai Hitoshi , Suzuki Nobuo
Published: July 2006

The transfer-free energies of the keto form, the enol form, and the transition state of benzoylacetone from water to water–dimethyl sulfoxide (DMSO) mixtures have been evaluated on the basis of kinetic and partition experiments at 25 °C. The results were compared with those of acetylacetone, and the substituent effects of methyl and phenyl groups on the transfer-free energies have been discussed in terms of the group transfer-free energy.
ESR and Optical Spectra of Low-spin Square Planar Cobalt(II) Complexes with Some Quadridentate Schiff Bases of the N2S2 Type
Authors: Nishida Yuzo , Sumita Akira , Kida Sigeo
Published: July 2006

ESR and electronic spectra of low-spin cobalt(II) complexes with some quadridentate Schiff bases of the N2S2 type were measured. Analysis of ESR parameters led to the conclusion that an unpaired electron is in the dyz orbital of the cobalt atom. On this basis the absorption at 10×103 cm−1 was attributed to the dx2−y2→dyz transition.
ENDOR Studies of Alkylated Biphenyl Anion Radicals in Solution. Relation between Molecular Size and Optimum Temperature of ENDOR Enhancement
Authors: Ishizu Kazuhiko , Ohnishi Masayoshi , Shikata Hideo
Published: July 2006

The ENDOR spectra of several alkylated biphenyl anions With para- and meta-substitutions were observed, and the relation between the molecular size and the optimum temperature of ortho-proton ENDOR were investigated in terms of the electron-nuclear dipole-dipole interaction. On the basis of the Stokes-Einstein model, a linear relation was found between the inverse of the effective radius and the cubic root of the η/T value at the optimum temperature of the ortho-proton ENDOR, under the assumption that the radical anion undergoes rotation accompanied by the solvent shell. In this situation, the separation between the radical anion and the counter cation thus estimated is more than 8.3 Å and the ion pair exists as a solvent-separated ion pair.
Organic Photochemical Reactions. XXV. The Photoaddition of 1-Phenyl-1,2-propanedione to Olefins
Authors: Shima Kensuke , Takeo Shigeki , Yokoyama Ken-ichi , Yamaguchi Hideaki
Published: July 2006

The irradiation of 1-phenyl-1,2-propanedione and olefins, such as 2,3-dimethyl-2-butene and α-methylstyrene, in benzene gives mainly oxetanes, in sharp contrast to the results obtained from the photoaddition of biacetyl to these olefins. The differences between these results are discussed in terms of the reactivity of the 1,4-biradical intermediates.
Further Studies on the Decarboxylation of Cinnamylidenemalonic Acid in Resorcinol and Catechol
Authors: Haleem M A , Hakeem M A
Published: July 2006

Kinetic data are reported for the decarboxylation of cinnamylidenemalonic acid in resorcinol and catechol. The activation parameters are culculated and compared with those previously reported for the decarboxylation of unsubstituted and substituted malonic acids.
A Study of the Asymmetric Reaction of Methyloxirane with Acetic Acid Catalyzed by an Optically-Active Cobalt Complex
Authors: Ishimori Michihiro , Aoi Haruhiko , Tezuka Yasuyuki , Tsuruta Teiji
Published: July 2006

A novel asymmetric reaction of methyloxirane with acetic acid catalyzed by an optically-active Co(salen)-type complex was explored. The products were identified to be propylene diacetate, 2-hydroxypropyl acetate, and 2-hydroxy-1-methylethyl acetate. The mechanistic features of this resolution-type reaction were characterized by the optical activities of the products and of the unchanged methyloxirane.
On the Lowest Triplet State of the Pyridazine Crystal
Authors: Marzzacco Charles J
Published: July 2006

The lowest singlet-triplet transition recently observed at 440 nm by Yamamoto, Takemura, and Baba for pyridazine in EPA is shown to correlate with the 410 nm transition observed by Hochstrasser and Marzzacco. This correlation is contrary to that of Yamamoto et al.
Calorimetric Study of the Glassy State. XI. Plural Glass Transition Phenomena of Cyclohexene
Authors: Haida Osamu , Suga Hiroshi , Seki Syûzô
Published: July 2006

Two kinds of glassy crystalline phases (I and III) of cyclohexene were realized by different thermal treatments. The heat capacities of the glassy and the supercooled crystal-I and -III, as well as the stable crystalline phases were measured by an adiabatic calorimeter in the temperature range 12–300 K. The glass transition temperature Tg, the heat capacity jump at Tg and the residual entropy were found to be 81 K, 11.4 JK−1 mol−1 and 11.7 JK−1mol−1 for crystal-I and 83 K, 3.6 JK−1 mol−1 and 2.6 JK−1 mol−1 for crystal-III, respectively. The glassy liquid state of cyclohexene was realized by vapor condensation technique, its Tg being 78 K as determined by DTA method. The results provide the first example of plural glass transition phenomena in one and the same lowmolecular-weight compound.
Calorimetric Study of the Glassy State. XIII. Thermodynamic Properties of Normal and Deuterated Orthoboric Acid Crystals
Authors: Oguni Masaharu , Matsuo Takasuke , Suga Hiroshi , Seki Syûzô
Published: July 2006

Thermal properties of normal and deuterated orthoboric acids were studied through the measurements of heat capacity in the temperature range from 13 to 370 K by using an adiabatic calorimeter and differential thermal analysis curves above room temperature. For both crystals, the heat capacity anomaly was found around 290 K in the heat capacity values dependent upon the thermal history of the specimen; i.e., the endothermic or exothermic enthalpy relaxation was observed in this temperature range. This behavior is of characteristic to the glass transition and is considered to be ascribed to the freezing-in phenomenon of the motion of rearrangement of the protons in hydrogen bondings. The enthalpy relaxation curves were analyzed with the exponential law and the characteristic time constant toward the equilibrium state was longer for enthalpy-excessive side than for enthalpy-deficient side. The glass transition temperature at which the endothermic relaxation time becomes 1 ks is 296.6 K for normal orthoboric acid and 298.2 K for deuterated orthoboric acid, respectively. The activation enthalpies were estimated to be 88±5 and 91±5 kJ mol−1 for the endothermic processes of normal and deuterated orthoboric acid, respectively. The melting points of normal and deuterated orthoboric acids were determined from the differential thermal analysis curves to be 169.9 and 167.4 °C, respectively.
Catalytic Activity of Silver and Gold Metals Doped with Alkali Metals
Authors: Hayashi Shigenobu , Soma Mitsuyuki , Kondow Tamotsu , Onishi Takaharu , Tamaru Kenzi
Published: July 2006

When alkali metals are brought into contact with silver or gold, catalytic activity for hydrogen activation reactions results which is higher than that for each of the constituent metals. The order of the activity per mole of alkali metal for the H2-D2 exchange reaction is Ag–C>Ag–K>Au–Cs>Ag–Na. The Ag–Cs and Ag–K systems absorb considerable amounts of hydrogen. The nature of the active sites and the contact effect of the IB metal with the alkali metal are discussed.
The Absorption Spectra of Disubstituted Benzenes. Interpretation by Means of Configuration Analysis
Authors: Fujii Tsuneo , Suzuki Satoshi , Fujishima Michiyuki
Published: July 2006

The method of configuration analysis has been applied to the interpretation of the ground and the excited states of disubstituted benzenes with two electron-donating groups, o-, m-, and p-benzenediols and o-, m-, and p-phenylenediamines, with particular attention paid to the dependence of the spectra on the positions of substitution and on the molecular symmetry. The wave functions calculated by the Pariser-Parr-Pople method are analyzed in terms of locally-excited states and intramolecular charge-transfer states. The characteristic changes in the location of the Lb, La, and Bb bands caused by substitution are adequately explained by the analysis. The intensification of the Lb band caused by the introduction of the substituents is interpreted as due to the mixing between the Lb, Bb, and Ba bands for the o- and m-substituted benzenes and between the Lb and Bb bands for the p-disubstituted benzenes. It was found empirically that the magnitudes of the spectral shift from benzene to the derivatives are determined primarily by the extent of charge-transfer contributions.
The Theory of the Adsorption Monolayer with Lateral Intermolecular Interaction and Its Application to Aqueous Alcohol Solutions
Authors: Nakagaki Masayuki , Yamamoto Mihoko
Published: July 2006

A theoretical relation between the fractional adsorption amount, θ, and the concentration, C, taking account of the lateral interaction between the adsorbed molecules is used to integrate the Gibbs equation, and the relation between the surface pressure, F, and the molecular area, A, is derived. Since the equation does not contain the parameter, k0, related to the strength of adsorption, it is concluded that there is no substantial difference between the adsorption monolayers and the insoluble monolayers. The relation between F and C is also derived and compared with the experimental data for normal alcohols. The standard affinity of adsorption, −Δμ0, and the energy of lateral interaction, ε, increased linearly with the number of carbon atoms of the alcohols, n. Finally, it has been shown that the experimental data can be explained well with the theoretical equation presented here, but not with Szyszkowski’s, the latter being derived for negligible lateral interaction.