bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the Lanthanoid Chelates of 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone. An Examination of the Phenomenon of Hypersensitivity
Authors: Roy Ajoy , Nag K
Published: July 2006

1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (Hpmbp) form complexes with lanthanoids of the type Ln(pmbp)3· nH2O (n=4 for La–Sm, and n=1 for Eu–Yb and Y), Ln(pmbp)3·2pyridine·2H2O, Ln(pmbp)3·(2,2′-bipyridine/1,10-phenanthroline)·C2H5OH, NH4[Ln(pmbp)4]·C2H5OH and Q+[Ln(pmbp)4]·C2H5OH, where Q+ is the quaternary ammonium cation of piperidine, pyrrolidine or morpholine. These compounds have been characterized from physicochemical studies. The electronic spectra of the Nd(III) complexes have been studied in detail to investigate the phenomenon of hypersensitivity with respect to the coordination environment and solvent medium. In these compounds solvent does not play a significant role to cause variation in hypersensitivity. The oscillator strengths of the hypersensitive transition in these compounds show the following trend: Q+[Nd(pmbp)4]>Nd(pmbp)3·phen>Nd(pmbp)3·bpy>Nd(pmbp)3·2py·2H2O>Nd(pmbp)3·2H2O. In the Pr(III) complexes the band due to 3H4→1D2 transition has been found to be hypersensitive, and the gradation of intensity due to this band follows almost the same trend as in the corresponding Nd(III) complexes.
Effect of Monohydroxy Alcohols and Urea on the CMC of Surfactants
Authors: Singh H N , Swarup Shanti
Published: July 2006

The effect of monohydroxy alcohols on the critical micelle concentration (CMC) of anionic and cationic surfactants have been studied by a conductometric method. The CMC was found to decrease by adding small quantities of alcohol and raised again at higher alcohol concentrations. The CMC decreasing effect has been discussed on the basis of more ordered water cavity formed around the added alcohol molecules and their increasing effect by the partition of alcohol between the micellar and the bulk phase leading to the break-down of the micelles. The effect of urea on CMC in alcohol–water mixtures has been studied and its CMC increasing effect explained.
Studies on Spontaneous Emulsification. III. Molecular Interaction at the Oil–Water Interface
Authors: Ogino Keizo , Umetsu Hidetoshi
Published: July 2006

At the oil–water interface, measurements of the interfacial tension were performed simultaneously with the observation of spontaneous emulsification. The effects of an oil-soluble alcohol (1-dodecanol) and a water-soluble surfactant (SDS) on the interfacial tension and on the spontaneous emulsification were studied.
Complex Anion Radical Salts Derived from Dicyanomethylenetrinitrofluorene
Authors: Matsunaga Yoshio , Yoshida Yuji
Published: July 2006

Four anion radical salts of the 2 : 3 type were derived from 9-dicyanomethylene-2,4,7-trinitrofluorene. Their electronic spectra, the ESR spectra characteristic of triplet excitons, and the electrical properties were measured.
Spectroscopic Similarity of Charge-Transfer Absorptions in Crystalline Complex Ion Radical Salts
Authors: Iida Yôichi
Published: July 2006

Charge-transfer transition between ion radical molecules takes place in crystalline ion radical salts. Spectroscopic similarity of the charge-transfer absorptions between certain systems of complex ion radical salts has been studied with use of a one-dimensional Hubbard model.
Solvolysis in Carboxamides. III. Solvolysis Rates of 1-Adamantyl Bromide and Tosylate, 2-Adamantyl Tosylate, and t-Butyl Chloride in Carboxamides
Authors: Saito Seiki , Doihara Kenji , Moriwake Toshio , Okamoto Kunio
Published: July 2006

Rate constants for the solvolysis of 1-adamantyl bromide and tosylate, 2-adamantyl tosylate, and t-butyl chloride in the four carboxamide solvents, i. e., N,N-dimethylacetamide, N,N-dimethylformamide, N-methylacetamide, and N-methylformamide, have been determined. The role of the carboxamides as solvolytic solvents has been discussed on the basis of linear free-energy relationship.
Effect of Hydration on the Thermal Denaturation of Lysozyme as Measured by Differential Scanning Calorimetry
Authors: Fujita Yukihisa , Noda Yukinao
Published: July 2006

The thermal properties of the lysozyme-water system were investigated by differential scanning calorimetry under varied water contents, ranging from 0.05 to 1.6 g per g of protein. The temperature, Td, and the enthalpy change, ΔHd of denaturation at water contents below 0.75 g/g showed strong dependencies on the hydration. At higher water contents, however, Td and ΔHd were almost independent of the degree of hydration, showing values almost identical to those in solution.
Studies on Heterocyclic Analogs of Azulenes. IV. Behavior of 2-Chlorocyclohepta[b]pyrrole Derivatives toward Phosphorus Ylide
Authors: Nishiwaki Tarozaemon , Abe Noritaka , Ishida Kozue , Miura Kaoru
Published: July 2006

The transylidation reaction of methyl(triphenylphosphoranylidene)acetate with 2-chlorocyclohepta[b]pyrrole derivatives has been studied. 3,8-Disubstituted derivatives gave a transylidation product only, whereas 3-substituted derivatives afforded not only a transylidation products but also the compounds formed by the addition of ylide at C-8. 13C NMR spectra of the transylidation products are recorded in part.
Studies on Aziridine-2-carboxylic Acid. I. Synthesis of the Optically Active l-Aziridine-2-carboxylic Acid and Its Derivatives
Authors: Nakajima Kiichiro , Takai Fumiko , Tanaka Takumi , Okawa Kenji
Published: July 2006

Lithium l-aziridine-2-carboxylate was synthesized from N-trityl-l-aziridine-carboxylic acid benzyl ester by the treatment with trifluoroacetic acid followed by the saponification with lithium hydroxide. Several N-acylaziridine-2-carboxylic acid esters were synthesized in good yield.
Rotational Isomerism and Vibrational Assignments of Monobromothioacetic Acid
Authors: Randhawa H S , Walter W
Published: July 2006

The infrared and Raman spectra of monobromothioacetic acid have been recorded and vibrational assignments proposed for the two symmetrical rotational isomers present in the acid.
Defect Chemistry of Barium Monoferrite, BaFe2O4−δ
Authors: Nakamura Akio , Yamauchi Shigeru , Fueki Kazuo , Mukaibo Takashi
Published: July 2006

In order to obtain information on the defects in ternary oxide systems, the nonstoichiometry and electrical conductivity of BaFe2O4 were determined at temperatures between 1050 and 1125 °C. The electrical conductivity was found to be proportional to PO2−1⁄6. This relationship suggests that BaFe2O4 is an oxygen deficient n-type semiconductor at high temperatures. The nonstoichiometry was proportional to PO2−1⁄2.88. order to interpret the dependence of electrical conductivity and nonstoichiometry on the oxygen partial pressure, various defect models were examined. As a result the following equilibria were selected from among the oxygen vacancies V0·· and V0x, and oxygen gas.

null=(1⁄2)O2+V0x

V0x=V0··+2e′

An analysis based on the above defect model explains the data well.
The Molecular Structure of Ethyl Chloride as Determined by a Combined Use of the Electron-diffraction Data and the Spectroscopic Moments of Inertia
Authors: Hirota Masashi , Iijima Takao , Kimura Masao
Published: July 2006

The molecular structure of ethyl chloride has been determined by a joint analysis of the electron-diffraction data and the moments of inertia obtained by Schwendeman and Jacobs by means of microwave spectroscopy. In the analysis, a staggered conformation with Cs symmetry for the molecule and a local C3v symmetry about the C–C axis for the methyl group were assumed. Under the further assumptions that \varphiav(HCH)CH2 is 109.2±2° and \varphiav(CCH)CH2 is in the range of 113.6–109.6°, the following parameter values were determined: rg(C–C) 1.528(4) Å; rg(C–Cl), 1.802(3) Å; rg(C–CI), 2.746(5) Å; rg; rg(C–H)CH2, 1.103(4) Å; \varphiav(HCH)CH2, 110.0(1.6)°; and \varphiav(CCCl), 110.7(0.3) °. The rg and rs distances for the C–Cl and C-C bonds of various chlorinated alkanes were plotted against the difference between the numbers of methyl groups and chlorine atoms, Δn=n(CH3)–n(Cl). In general, as the number of chlorine atoms increases, both distances become shorter, though the rg distances are longer than the rs distances by 0.01–0.03 Å.
Minima in the Solubilities of Normal Alkane Derivatives with a Polar Group in Water
Authors: Nishino Nobuo , Nakamura Masao
Published: July 2006

The change in the solubility in water with the temperature was measured for alkanols, alkylamines, and alkanoic acids. It has been found that a minimum exists commonly on the solubility-temperature curve. This minimum dissolution point, Pm, may be regarded as a characteristic point with respect to the solute. The change in the solubility with the temperature has been explained in terms of the increase in the partial molar enthalpy of the solute in solution with an increase in the temperature, which results from the breakdown of the ice-like structure of water formed around the nonpolar alkyl group. Both the concentration, xm, and temperature, Tm, at point Pm decrease with an increase in the number of carbon atoms in the alkyl group, m. The decrease in In xm by the addition of one methylene group is steeper in the order of alkanoic acids, alkylamines, and alkanols, while the corresponding decrease in Tm shows the reverse order. In addition, Tm is related to the cohesive energy of the solute in the pure state.
Application of Microwave Spectroscopy to Kinetic Study of the Reaction of Carbonyl Sulfide with Atomic Oxygen
Authors: Yoshida Noritetsu , Saito Shuji
Published: July 2006

Microwave spectroscopy has been applied to the determination of the rate constant for OCS+O→SO+CO. A short cell of a parallel-plate type was devised for the detection of the SO radicals produced in a fast flow reactor. Production of the SO radical was traced by measuring its spectral line intensity under the condition of [OCS]>>[O]. The rate constant for the reaction was determined to be (7.1±0.7)×109 cm3/mol·s at room temperature (24–25) °C, in good agreement with the values obtained by other methods.
Determination of Micro Amounts of Polythionates. X. Spectrophotometric Determination of Micro Amounts of Pentathionate in Mixtures with Thiosulfate and Sulfite by Means of Its Sulfitolysis
Authors: Koh Tomozo , Taniguchi Kazuo , Iwasaki Iwaji
Published: July 2006

An accurate method has been proposed for the determination of pentathionate in mixtures with thiosulfate and sulfite. The method is based on the formation of thiosulfate equivalent to the pentathionate, and the spectrophotometric determination of excess iodine for the reaction with the thiosulfate formed. The conditions for pentathionate to be quantitatively converted into thiosulfate were established by varying pH, reaction time, and amounts of sulfite. The method can be successfully applied to the determination of pentathionate, thiosulfate, and sulfite when they are mixed in various ratios, giving a relative standard deviation of 0.82% at the 0.5 μmol level of pentathionate in a 10.0 cm3 sample solution in the presence of 0.5 μmol of thiosulfate and 0.25 μmol of sulfite.
The Application of a Quadrupole Mass Spectrometer to a Study of Methane Oxidation in Shock Waves
Authors: Hidaka Yoshiaki , Nagayama Midori , Suga Masao
Published: July 2006

A part of the mass-spectrometer shock-tube apparatus was improved, and its working characteristics were examined. The oxidation of methane was studied with this apparatus over the temperature range of 1800–2500 K and the total pressure range of 360–560 Torr at O2/CH4 ratios of 1–3. The induction period was measured by monitoring the oxygen concentration, and the following equation was found to hold:

τ=4.54×10−10[CH4]0.37[O2]−0.64exp(35600⁄RT) s

in which the concentrations were expressed in mol per cubic centimeter.
Molecular Dissociation of 3-Cyclopenten-1-one Photosensitized by Excited Mercury (3P1)
Authors: Nakamura Kazumoto , Koda Seiichro , Akita Kazuo
Published: July 2006

The mercury photosensitized decomposition of 3-cyclopenten-1-one produced carbon monoxide and 1,3-butadiene in equal quantum yields as the exclusive products, independent on the absence or presence of nitrogen oxide. Thus the process was a molecular dissociation. The quantum yield was dependent on the pressure of argon added as a third body and revealed a maximum at the pressure of about 100 mmHg. A possible reaction scheme was proposed to explain the above kinetic behavior. It was suggested that the vibrationally excited state of 3-cyclopenten-1-one was a main precursor to decompose to carbon monoxide and 1,3-butadiene. An energy about 20 kcal·mol−1 was estimated to be lost before its production from the original triplet state 3-cyclopenten-1-one according to the proposed reaction scheme. This result is compared with the behaviors of excited 3-cyclopenten-1-ones produced by different excitation procedures.
Luminescence Properties and the Primary Process of Photochromism of 2-(2-Hydroxyphenyl)benzothiazole
Authors: Nakagaki Ryoichi , Kobayashi Takayoshi , Nagakura Saburo
Published: July 2006

The luminescence behavior of 2-(2-hydroxyphenyl)benzothiazole at 77 K was studied in detail, special attention being paid to dual fluorescence at ≈500 and ≈370 nm and also to phosphorescence at ≈500 nm. From the dependence of these emission bands upon the hydrogen-bonding ability of solvents and the excitation spectra, it is concluded that the short- and long-wavelength fluorescence bands are due to the intermolecularly hydrogen-bonded enol imine and the keto amine produced from the intramolecularly hydrogen-bonded enol, respectively, and that the phosphorescence is due to the intermolecularly hydrogen-bonded enol imine. The estimated quantum yield of the enol fluorescence gives further support to the formation scheme of the photochromic colored species previously presented. The rate constants of the intramolecular hydrogen transfer at 77 and 293 K are evaluated to be larger than 4×1010 s−1 and 3×1012 s−1, respectively.
Heterogeneous Catalysis in Liquid-Phase Oxidation of Olefin. II. Dependence of the Structure of Vanadium–Chromium Binary Oxide Catalyst for Oxidation of Cyclohexene on the Method of Preparation
Authors: Takehira Katsuomi , Hayakawa Takashi , Ishikawa Toshio
Published: July 2006

The influence of preparative conditions on the structure and catalytic activity of V–Cr oxide catalyst for the liquid-phase oxidation of cyclohexene has been investigated. Three series of binary oxide, V–Cr-D, V–Cr-E, and V–Cr-F, were prepared from acidic, neutral, and alkaline media, respectively. The specific activity of the catalyst was found to be in the order: V–Cr-D>V–Cr-E>V–Cr-F, the catalyst prepared from acidic medium showing the highest activity. The results of structure analysis showed the formation of several chromium isopolyvanadates, i.e., chromium pyrovanadate, chromium metavanadate, and unknown phase (probably chromium polyvanadates), together with V2O5, Cr2O3, and solid solution of Cr6+ in V2O5 lattice. The formation of chromium isopolyvanadate having a higher degree of condensation of the vanadate anion was promoted by use of a more acidic medium in the catalyst preparation. The higher activity for autoxidation was obtained with the catalyst containing the more condensed isopolyvanadate. Epoxidation seems to proceed by the hydroperoxide intermediate mechanism on the active site differing from that for autoxidation.
Interactions of Calcium Ions with Carbohydrates: Crystal Structure of Calcium Dl-Glycerate Dihydrate
Authors: Taga Tooru , Ohashi Makoto , Osaki Kenji
Published: July 2006

The crystal structure of calcium Dl-glycerate dihydrate has been determined by the heavy atom method. The crystal is monoclinic, space group P21/c, with unit cell dimensions: a=14.40, b=7.63, c=10.40 Å, and β=98.8°. Two independent glycerate anions have different conformations. β-Hydroxy oxygen in one conformer is trans-gauche to α-carboxy carbon and α-hydroxy oxygen, while that in the other conformer is gauche-gauche. Ca–O interactions and hydrogen bonds stabilize the crystal structure. The calcium ion is bound to three glycerate anions and two water molecules, the two glycerate anions chelating the calcium ion with the α-carboxy oxygen and α-hydroxy oxygen, and third glycerate anion bonding to the calcium ion with β-hydroxy oxygen. Seven oxygens surround a calcium ion in a distorted pentagonal biprism arrangement with Ca–O distances ranging from 2.32 to 2.47 Å.
Abnormal Hyperchromism of the n→π* Absorption Band of Acetone in Protic Solvents
Authors: Yudasaka Masako , Hosoya Haruo
Published: July 2006

Concentration dependence (1–10−4 molar fraction) of the UV absorption spectra of the binary mixtures of (i) acetone–water, (ii) acetone–ethanol, and (iii) diisobutyl ketone–ethanol systems was studied. In (i) and (ii) distinct spectral changes of three steps were observed in succession, while in (iii) gradual changes in two steps were observed. The intensities of the n→π* band of very dilute solutions for these systems are enhanced, respectively, by 40, 20, and 15 per cent. The results were interpreted as the following stepwise equilibria

A+B\ightleftarrowsAB, AB+B\ightleftarrowsAB2, AB2+B\ightleftarrowsAB3

for (i) and (ii), while in (iii) the last step is obscured, where A and B denote, respectively, ketone and water or ethanol molecules. The structure of AB3 is discussed.
Bivalent and Tervalent Cobalt Complexes of 4-(2-Pyridylazo)resorcinol, 1-(2-Pyridylazo)-2-naphthol, and their Thiazolyl Analogs in Aqueous and Aqueous Dioxane Media. Rapid-scan Spectral and Kinetic Studies
Authors: Mochizuki Katsura , Imamura Taira , Ito Tasuku , Fujimoto Masatoshi
Published: July 2006

The reactions of Co2+ with 4-(2-pyridylazo)resorcinol (PAR), 1-(2-pyridylazo)-2-naphthol (PAN), and their thiazolyl analogs TAR and TAN in aqueous or aqueous dioxane media are followed by a rapid-scan spectroscopic method combined with stopped-flow technique. The step of the fast formation of cobalt(II) complexes is clearly discriminated from the subsequent slower step of oxidation to the cobalt(III) state. Formation and redissolution of transient insoluble intermediates are observed in the stopped-flow signals for the light scattered by the reaction mixture. The metal-to-ligand ratio in the short-lived intermediate cobalt(II) complex of PAR and PAN is determined to be 1 : 2 by applying the method of continuous variation to the fast change in stopped-flow signals. The rate constants k1 and k2 for the step of formation of 1 : 1 cobalt(II) complex with the species LHH* and LH− of PAR in aqueous solution and with the species LH2+ and LH of PAN in 5%(v/v) dioxane-water are determined to be k1=4.8×104 and k2=9.8×104 dm3 mol−1 s−1, and k1<103 and k2=4.6×103 dm3 mol−1 s−1, respectively.
Synthesis of Oxide-Chalcogenides. I. Hydrothermal Synthesis of Sarabauite CaSb10O10S6 and Related Compounds
Authors: Nagashima Kozo , Ogino Masataka , Nakai Izumi
Published: July 2006

Single crystals of a recently described metal oxide sulfide mineral sarabauite and three related oxide-sulfides of alkaline earths and antimony were hydrothermally synthesized. (1) CaSb10O10S6: color, carmine red; crystal system, monoclinic; space group, C2/c. (2) Compound in Sr–Sb–O–S system (OS), reddish orange, triclinic P1 or P\bar1. (4) Compound in Ba–Sb–S–O system (O<S), blackish brown, monoclinic, P21/a.
Synthesis and Spectroscopy of Acetato and Dithiocarbamate Complexes of Bis(cyclopentadienyl)zirconium(IV)
Authors: Suzuki Hideo , Takiguchi Toshio , Kawasaki Yoshikane
Published: July 2006

Several acetato and dithiocarbamate complexes of bis(cyclopentadienyl)zirconium(IV), Cp2Zr(X)OAc (X= Me, Cl, OAc), Cp2Zr(X)dmtc (X=Me, Cl; dmtc=S2CNMe2), and Cp2Zr(X)detc (X=Me, Cl; detc=S2CNEt2) have been prepared. Infrared, 1H NMR and mass spectra of these complexes suggest the chelation of acetato (except for one acetato group in Cp2Zr(OAc)2) and dithiocarbamate groups, affording 18-electron configuration of the zirconium atom. The infrared spectrum of diacetate bis(cyclopentadienyl)zirconium(IV) shows that one acetato group acts as bidentate ligand and the other as unidentate. Remarkable benzene- and hexafluorobenzeneinduced shifts were observed in the 1H NMR signal of methyl group attached to the zirconium atom and the dithiocarbamate group.
Nuclear Magnetic Resonance Study of Exchanging Systems. XI. 13C NMR Spectra of 9-Ethyltriptycene Derivatives and the Restricted Rotation of the Ethyl Group
Authors: Nakanishi Hiroshi , Yamamoto Osamu
Published: July 2006

9-Ethyl-1,4-dimethoxytriptycene, 1,5-dichloro-9-ethyltriptycene, and 9-ethyl-1,4-dimethyltriptycene were prepared. The 13C NMR spectra of these compounds were measured at low temperatures in order to obtain information about the restricted rotation of the ethyl group. It was found that the former two compounds have the meso isomer as well as the dl isomer. Different chemical shifts of the methylene carbons in the ethyl group, C(2) and C(3) of the benzene A ring, and some quaternary carbons in the two isomers of 9-ethyl-1,4-dimethoxytriptycene indicate that the 120°C rotation around Csp3–Csp3 single bond in the ethyl group deforms the benzene or bicyclo[2.2.2]octatriene skeleton. The complete line-shape analyses of the temperature-dependent 13C NMR spectra of this compound were performed, and the thermodynamic static parameters and activation parameters of the ethyl rotation were determined. The correlation between the rotational barriers of the alkyl groups and their bulkiness was briefly discussed.
The Synthesis of New Flavones with a 4H,10H-Benzo[1,2-b: 3,4-b′]dipyran-4,10-dione Skeleton and the Light Resistannce of These Compounds
Authors: Kaneta Makoto , Hikichi Hiroshi , Endo Seiichi , Sugiyama Noboru
Published: July 2006

Six analogous new flavones with a skeleton similar to arthraxin, which is a light-stable, natural, new flavone, have been synthesized by the use of a modification of Allan-Robinson’s flavone synthesis. The structures of these compounds were elucidated by means of the Gibbs reaction, NMR, and mass spectrometry. The light resistance of these flavones was then examined by means of UV spectrometry. The results indicate that these flavones, with a 4H, 10H-benzo[1,2-b : 3,4-b′] dipyran-4,10-dione skeleton, in contrast with natural common flavonol and arthraxin, show a high resistance to light.
The Effects of Solvents on the IR and PMR Spectra of Intramolecular OH…π and OH…O Hydrogen Bonded Systems
Authors: Ueji Shinichi
Published: July 2006

The effects of solvents on the intramolecular OH…π and OH…O hydrogen bonding in 2-arylphenols and 2,6-diarylphenols have been studied by examining the OH stretching IR absorption spectra in a range of solvents. The solvent shifts of the hydrogen bonded bands, νOH…π and νOH…O, followed the G correlation and the BHW plot. The success of both correlations suggests that the solvent shifts are primarily due to a specific solvent-solute association, even in relatively non-polar solvents. The solvent sensitivity of the OH…π and OH…O hydrogen bonded bands depended on the stereo-chemical environment around the hydrogen bonded system rather than on such electronic factors as the strength of the hydrogen bonding. On the basis of the relationship between the solvent sensitivity and the structural changes over a group of phenols, a simplified model for the solvent-solute association is put forward. Furthermore, this simplified model is also discussed in terms of the aromatic solvent-induced shifts in the PMR spectra.
The Reactions of 2-Arylacetylene-1-sulfonamides with Heterocumulenes
Authors: Hasegawa Kiyoshi , Hirooka Syuzi , Kawahara Hiroshi , Nakayama Akihiko , Ishikawa Keiichi , Takeda Nobuyuki , Mukai Hisakatsu
Published: July 2006

The syntheses of new heterocyclic compounds by the reaction of 2-arylacetylene-1-sulfonamides 1, (Z)-β-bromo- 12 or (Z)-α-chloro-β-styrenesulfonamides 13 with heterocumulenes are described. Weak base treatment of ureas R1C6H4C≡CSO2NHC(=O)NHR2 prepared from 1 and isocyanates gave 2-amino-6-aryl-1,4,3-oxathiazine 4,4-dioxides, whereas strong base treatment of the ureas afforded 3-oxo-4,5-diphenyl-2,3-dihydro-1,2,4-thiadiazine 1,1-dioxides where R2 is a phenyl group. The thiadiazines were also prepared by the strong base treatment of N-((Z)-α-bromo- or (Z)-β-chlorostyrylsulfonyl)-N′-phenylureas. The reaction of 1,12, or 13 with isothiocyanates in the presence of weak base gave 3-amino-5-aryl-1,4,2-dithiazine 1,1-dioxides, but the major products produced were 3-amino-5-benzylidene-1,4,2-dithiazole 1,1-dioxides when 12a was treated with isothiocyanates in the presence of strong base. The reaction of 1 with carbon disulfide and dimethyl sulfate in the presence of 5 M NaOH afforded 3-methylthio-5-benzylidene-1,4,2-dithiazole 1,1-dioxide with a small amount of 3-methylthio-5-aryl-1,4,2-dithiazine 1,1-dioxide. A mixture of both isomers was also prepared from 12a. Possible mechanisms for the formation of the heterocycles from 1, 12, or 13 are suggested.
The Hydrolysis of Carbohydrates in the Presence of a Reversed Micelle. II. The Hydrolysis of Sucrose in Benzene
Authors: Arai Kenichiro , Ogiwara Yoshitaka
Published: July 2006

The formation of a reversed micelle by dodecylbenzenesulfonic acid in benzene containing a certain amount of water was examined by means of the absorption spectra of the Methylene Blue added to the system. The hydrolysis of the sucrose secondary-solubilized in the system was then investigated. The maximum rate enhancement of 400-fold was obtained in the presence of the micelle on the basis of the reaction in an aqueous solution in the presence of hydrochloric acid, whereas the addition of ethanesulfonic acid to the system showed only a little effect on the reaction rate. The reaction rates were found to show behavior similar to that of the stability of the micelle with respect to changes in the substrate concentration and in the amount of solubilized water. From these results, the greater part of the rate enhancement obtained in the present system might be concluded to result from some effects due to the formation of the reversed micelle.
The Reactions of Olefins with Chloromethoxymethane or Dimethoxymethane in Nitriles
Authors: Wada Yasuo , Yamazaki Takeshi , Nishiura Kazuo , Tanimoto Shigeo , Okano Masaya
Published: July 2006

The Lewis acid-catalyzed reactions of olefins with chloromethoxymethane (CM) or dimethoxymethane (DM) and aliphatic or aromatic nitriles afforded the 1 : 1 : 1 adducts and/or their hydrolysis products in various yields, together with the 1 : 1 olefin–CM (or DM) adducts. AlCl3, FeCl3, ZnCl2, and SnCl4 were effective catalysts for the reaction with CM, whereas BF3 and SnCl4 were effective for that with DM. In the case of cyclohexene, the addition proceeded in the trans-manner; i.e., the methoxymethyl group and the nitrile molecule were added to the olefin from opposite sides.
Sensitized Photooxygenation of 9-Vinylphenanthrenes
Authors: Matsumoto Masakatsu , Dobashi Satoshi , Kondo Kiyosi
Published: July 2006

The sensitized photooxygenation of several 9-vinylphenanthrenes in carbon tetrachloride was investigated. In the cases of 9-vinyl- and 9-(β-substituted vinyl) phenanthrenes, the 1,4-cycloaddition of singlet oxygen to a conjugated system composed of the side chain and 9,10-double bond of the ring surpassed other oxidation modes, i.e., the “ene” reaction and 1,2-cycloaddition of singlet oxygen, to give the 1,2-dioxatriphenylene-type peroxides. On the other hand, the sensitized photooxygenation of 9-isopropenylphenanthrene gave a hydroperoxide due to the “ene” reaction.
New β-Carbonylvinylpalladium(II) Complexes Derived from 2-Chlorovinyl Ketones and Tetrakis(triphenylphosphine)palladium(0)
Authors: Onishi Masayoshi , Yamamoto Hideharu , Hiraki Katsuma
Published: July 2006

Chloro(trans-3-oxo-3-phenyl-1-propenyl)bis(triphenylphosphine)palladium(II), chloro (trans-3-oxo-3-p-tolyl-1-propenyl)bis(triphenylphosphine)palladium(II), chloro(3-oxo-1-cyclohexenyl)bis(triphenylphosphine)palladium(II), and chloro(5,5-dimethyl-3-oxo-1-cyclohexenyl)bis(triphenylphosphine)palladium(II) were prepared by reactions between Pd(PPh3)4 and linear or cyclic 2-chlorovinyl ketones. The halogen metathesis reactions with LiBr yielded the corresponding bromo complexes. Each of the β-carbonylvinyl groups in these eight complexes was found to be situated at the trans position to a palladium-halogen bond, on the basis of IR and 1H-NMR studies. The complexes with the cyclic β-carbonylvinyl groups were rather stable. The oxidative addition of linear 2-chlorovinyl ketones proceeded with retention of configuration about the double bond.
The Reactions of 2-Fluoro-1,3,5-trinitrobenzene (FTNB) as a New Condensing Reagent
Authors: Inomata Katsuhiko , Kinoshita Hideki , Fukuda Hirohiko , Tanabe Kumiko , Kotake Hiroshi
Published: July 2006

2-Fluoro-1,3,5-trinitrobenzene (FTNB) was found to be a useful new condensing reagent. Various amides, esters and thiocarboxylic S-esters were prepared in good yields from carboxylic acids with the reagent.
Asymmetric Reduction of Prochiral Ketones with Chiral Hydride Reagents Prepared from Lithium Aluminium Hydride and (S)-2-(N-Substituted aminomethyl)pyrrolidines
Authors: Asami Masatoshi , Ohno Hiroyasu , Kobayashi Susumu , Mukaiyama Teruaki
Published: July 2006

Asymmetric reduction of prochiral ketones with various hydride reagents prepared from lithium aluminium hydride and (S)-2-(N-substituted aminomethyl) pyrrolidines, derived easily by four steps from commercially available (S)-proline, yields optically active alcohols with 13–92% optical purity having the S-configuration.
Gas-chromatographic Studies of the Thermal Decompositions of Carbonato-pentaammine-, Carbonatotetraammine-, and Dicarbonato- diamminecobalt(III) Complexes in the Solid State
Authors: Onodera Sukeo
Published: July 2006

This paper will describe gas-chromatographic studies of the thermal decompositions of [CoOCO2(NH3)5]X·H2O (I), (CoCO3(NH3)4]X·nH2O (II), and K[Co(CO3)2(NH3)2(NH3)2]·H2O (III) (where, X=Cl, NO3, SO4, and n=0, 0.5, 3). The GEA curves for these compounds show that the complexes lose water between 80 and 160 °C, and that the decomposition of the anhydrous compounds begins with an evolution of ammonia at about 140 °C (for I) and 180 °C (for II and III).
Electrochemical Fluorination of Thiols
Authors: Baba Hajime , Kodaira Kazuo , Nagase Shunji , Abe Takashi
Published: July 2006

Electrochemical fluorination of C3 and C4 thiols has been investigated. Perfluoroalkylsulfur pentafluoride derivatives including new compounds, together with fragmented fluorocarbons and sulfur hexafluoride, have been formed.
Magnetic Circular Dichroism Spectra of Amino Acid Complexes of the [CoIII(N)5(O)]n+ Type
Authors: Ueda Etsuyo , Matsuoka Nobuko , Shimura Yoichi
Published: July 2006

MCD spectra of amino acid complexes of [Co(NH3)5(OCOCHRNH3)]3+, [Co(NH2CHRCO2)(NH3)4]2+, and [Co(NH2CHRCO2)(en)2]2+ types have been measured. The complexes belonging to a given type show nearly identical MCD curves irrespective of variation in their natural CD patterns. The complexes of d-, l-, and Dl-alanine show identical MCD spectra.
A Proton Magnetic Resonance Study of the Amide Configurations of 2-Acetoacetamido Derivatives of 4-Methylpyridine and Pyrimidine
Authors: Kondo Michio
Published: July 2006

It has been found by 1H NMR spectroscopy that 2-acetoacetamido-4-methylpyridine (1) and 2-acetoacetamidopyrimidine (2) exist predominantly in keto forms in CDCl3 and DMSO. The amide group of 1 seems to be in a s-trans configuration in both solvents, whereas that of 2 is in a s-cis form in CDCl3, but predominantly in a s-trans isomer in DMSO at room temperature. Configurations of the enol forms are discussed.
Application of Structure Construction Logic in CHEMICS for Determination of Amino Acid Sequence of Polypeptide by CI Mass Spectrometry
Authors: Yotsui Yasuhiko , Nomura Hisashi , Sano Mitsuji , Kudo Yoshihiro , Sasaki Shin-ichi
Published: July 2006

The amino acid composition for each ligopeptide fragment in the hydrolysis mixture of polypeptides was determined using mass spectrometer with a CI source. The amino acid sequence was elucidated by structure construction logic in CHEMICS.
Solvent Incorporation in Bromination of Acetylenes in Alcohols
Authors: Uemura Sakae , Okazaki Hajime , Okano Masaya , Sawada Seiji , Okada Atsuko , Kuwabara Kimiko
Published: July 2006

The reactions of acetylenes with bromine in alcohols at 20–25 °C afford dibromodialkoxyalkanes in good yields together with variable amounts of dibromoalkenes. Similar treatment of phenylacetylene with copper(II) bromide gives only bromophenylacetylene and 2-phenyl-1,1,2-tribromoethylene, the latter being formed by dibromination of the former with copper(II) bromide.
Conversion of Disilanes to Functional Monosilanes. IV. Synthesis of Methyldichlorosilane and Dimethylchlorosilane by the Reaction of Methylchlorodisilanes with Hydrogen Chloride in the Presence of Tetrakis(triphenylphosphine)palladium(0)
Authors: Matsumoto Hideyuki , Motegi Tsuneo , Hasegawa Minoru , Nagai Yoichiro
Published: July 2006

Methylchlorodisilanes such as 1,2-dimethyl-1,1,2,2-tetrachlorodisilane, 1,1,2-trimethyl-1,2,2-trichlorodisilane and 1,1,2,2-tetramethyl-1,2-dichlorodisilane were effectively cleaved by hydrogen chloride in the presence of tetrakis(triphenylphosphine)palladium(0) to give methylchlorohydrosilanes in good yields.
A Simple Synthetic Method for 2,15-Hexadecanedione from a Butadiene Telomer
Authors: Tsuji Jiro , Kaito Mitsumasa , Yamada Toshiro , Mandai Tadakatsu
Published: July 2006

The terminal double bond of 3,8-nonadienoate was oxidized to methyl ketone with a catalyst system of PdCl2/CuCl/O2 and the internal double bond was reduced to give 8-oxononanoate, which was hydrolyzed to 8-oxononanoic acid. The Kolbe electrolysis of the acid produced 2,15-hexadecanedione in a high yield.
A Molecular Orbital Study of the Electrophilicity of Hydroxyl Radical in Hydrogen Abstraction Reaction
Authors: Shinohara Hiroyuki , Imamura Akira , Masuda Takahiro , Kondo Masaharu
Published: July 2006

The electrophilicity of the hydroxyl radical in hydrogen abstraction from methane was studied by the CNDO/2 method. The stabilization energy due to the delocalization of the electrons (SEDE) between methane and the radical at a close distance was calculated. The electrophilicity defined by the SEDE from methane to the hydroxyl radical was larger than the nucleophilicity defined by that from the hydroxyl radical to methane. This result is consistent with the electrophilicity observed in hydrogen abstraction by the hydroxyl radical from a series of substituted methanes. For sulfhydryl radical, the electrophilicity was also suggested by the calculation for hydrogen abstraction from methane. The calculations were also carried out for various radicals which have low electron affinity (hydrogen atom and methyl radical), and the SEDE from methane to the radical was found to be large compared with that from the converse case.
The Mechanism of Oxygen Reduction at a LaNiO3 Electrode
Authors: Matsumoto Yasumichi , Yoneyama Hiroshi , Tamura Hideo
Published: July 2006

The reaction mechanism of the O2 reduction at LaNiO3 was studied by using a rotating ring-disc electrode, which consists of a LaNiO3 disc and Pt ring electrodes. It was found that the O2 was completely reduced to OH− on the Hoare path. Oxygen vacancies seem to be required in the oxide surface for reduction of adsorbed O2H− to OH−.
The Structure of Water in the Vicinity of Complex Ions of Transition Elements in Their Aqueous Solutions as Revealed by the Shift of the Temperature of Maximum Density of Water
Authors: Wada Goro , Nagao Emiko , Kawamura Nagako , Kinumoto Kyoko
Published: July 2006

The temperature of the maximum density (TMD) of aqueous solutions was measured for twenty complex ions of transition metals. From the degrees of depression of TMD, Despretz’s constant kionD and the constant of excess depression of mixing Δkion were determined. These constants along with Bion coefficient of viscosity give us information on the structure of water in the vicinity of ions. [Co(H2O)6]2+, [Ni(H2O)6]2+, [Cu(H2O)6]2+, and [Zn(H2O)6]2+ are electrostrictive structure-breakers in the natural order of Irving-Williams, Co(II)<Ni(II)Zn(II). Of the complexes [Co(NH3)6]3+, [Co(en)3]3+, and [Co(pn)3]3+, the pn-complex is the strongest hydrophobic structure-maker due to the hydrophobic nature of its aliphatic constituent. Both [Fe(CN)6]3− and [Co(CN)6]3− are fairly strong electrostrictive structure-breakers, while [Fe(phen)3]2+, [Co(phen)3]2+, and [Co (phen)3]3+ are clathrate-like structure-makers. The EDTA and CyDTA complex ions of Co(II), Ni(II), Cu(II), and Zn(II) show no significant difference in kionD, the situation being complicated by the hydrophobicity of the ligands and the radius effect of the complex ion. The actions of ions as structure-makers should be classified into three categories; electrostrictive, hydrophobic (iceberg formation), and hydrophobic (clathrate-like structure formation). The characteristic influence of the structure-making nature on kionD, Δkion, and Bion is discussed.
Phase-shift Studies of Cadmium-photosensitized Luminescence of Ammonia and Some Aliphatic Amines
Authors: Umemoto Hironobu , Tsunashima Shigeru , Sato Shin
Published: July 2006

A phase-shift method was used to study the cadmium-photosensitized luminescence of ammonia and some aliphatic amines. The phase angles between the resonance fluorescence at 326.1 nm and the luminescence from the excited complexes have been measured at various modulation frequencies (10–99 kHz). The results could not be explained by means of the reaction mechanism proposed by analogy with the mercury-photosensitized luminescence of ammonia. In order to obtain a consistency, the equilibrium between the unstabilized and stabilized complexes: CdNH3†+NH3\ightleftarrowsCdNH3*+NH3, had to be taken into account. The reverse reaction was not necessary to explain the results of the mercury-photosensitized luminescence of ammonia. This discrepancy may be ascribed to the difference in the energy gap between the 3P1 and 3P0 states of mercury and cadmium.
Direct Measurement of the Interaction Energy between Solids and Gases. III. Comparison of the Calorimetric Titration Method with the Amine Titration Method for the Determination of Acid Strength Distribution of Silica-Alumina Surface
Authors: Taniguchi Hitofumi , Masuda Tatsuo , Tsutsumi Kazuo , Takahashi Hiroshi
Published: July 2006

The acid strength distribution of silica–alumina catalyst (alumina content 13 wt%) evacuated at 400 °C for 5 h was determined by the measurement of heat of adsorption of ammonia, and compared with that determined by amine titration by use of a series of Hammett indicators. The heats of adsorption of ammonia on silica–alumina poisoned with Hammett indicators were also measured in order to obtain the relation between the dissociation constant of the acid (pKa) and the heat of adsorption. When the dissociation constants of acid were equal to −5.6 and +3.3, the differential heats of adsorption of ammonia were observed to be 76.1 and 55.1 kJ/mol, respectively. The number of acid sites calculated from the heat vs. adsorbed amount curve was found to be about twice as large as that determined by amine titration. The discrepancy is discussed.
The Crystal Structure of l-Asparaginato-d-aspartatocobalt(III) Monohydrate
Authors: Sekizaki Masao
Published: July 2006

The crystal structure of l-asparaginato-d-aspartatocobalt(III) monohydrate, [Co(H2NCOCH2CHNH2COO)(OCOCH2CHNH2COO)]·H2O, has been determined by an X-ray diffraction method and refined by a block-diagonal least-squares method to give R=0.033 for 1517 non-zero reflections. The crystals are orthorhombic with the space group P212121, a=11.790(2), b=17.059(2), c=5.830(2) Å, and Z=4. The complex molecule has a slightly distorted octahedral coordination with fac(N) geometry. The amide group of l-asparaginate ion is coordinated through the nitrogen atom, and an enolic system of Co←NH=C(OH)–CH2– is formed. The complex molecules are held together through hydrogen bonds which form two-dimensional networks parallel to the (010) plane. The networks are piled up through hydrogen bonds by water molecules to complete three-dimensional networks.
Chemical Shifts of Sulfur KLL Auger Electron Energies in Its Compounds
Authors: Nishikida Shunichi , Ikeda Shigero
Published: July 2006

The sulfur 1s and 2p photoelectron spectra and KL23L23 Auger electron spectra in various sulfur compounds involving solid sulfur were measured by means of irradiation by Al Kα and Cr Kα X-rays. The chemical shifts of the S1s and S2p photoelectron spectra for compounds referred to the data for solid sulfur differ from each other in magnitude, but all are larger than that for the Auger electron spectra in the corresponding compound. The shift of the Auger electron spectra is different in fashion from those of the photoelectron spectra; the difference is largely attributable to the differences in relaxation energies. The extra-atomic relaxation energies due to core-electron emission were estimated by combining the atomic spectral data and the XPS and AES data of compounds; they were found not necessarily to depend upon the atomic charges. From the calculated sulfur Kα X-ray spectra corresponding to the difference in the binding energy between 1s and 2p, the number of electrons on each sulfur atom was obtained by using the method derived from Coulson et al., while the isolation was attempted on the basis of the contribution of polarization energies due to surrounding atoms to the extra-atomic relaxation energies.
Optical Activation of 2-Phenylpropionaldehyde via Some 2-Substituted Pyrrolidine Enamines
Authors: Matsushita Hajime , Tsujino Yasuko , Noguchi Masao , Saburi Masahiko , Yoshikawa Sadao
Published: July 2006

Optical activation of 2-phenylpropionaldehyde (PPA) via enamines using l-proline derivatives as amine components was studied. S(+)-PPA was obtained when R(−)-2-methylpyrrolidine and S(−)-2-ethoxycarbonylpyrrolidine were used, while R(−)-PPA was obtained when S(−)-prolinamide, N-(l-prolyl)pyrrolidine, N-(l-prolyl)piperidine, S(+)-2-(1-pyrrolidinylmethyl)pyrrolidine, and S(+)-2-(piperidinomethyl)pyrrolidine were used. This suggests that there are two mechanisms for optical activation.
Preparation and Reactivities of Phenylethynyl[1,1,1-tris(diphenylphosphinomethyl)ethane]copper(I) Complex
Authors: Hiraki Katsuma , Fuchita Yoshio , Morita Yasushi
Published: July 2006

Phenylethynyl[1,1,1-tris(diphenylphosphinomethyl)ethane]copper(I), [Cu(C≡CPh)(tdpme)]tdpme=1,1,1-tris(diphenylphosphinomethyl)ethane, has been prepared in good yield by a reaction between phenylethynyl-copper(I), [{Cu(C≡CPh)}n], and tdpme. From physicochemical and spectroscopic studies the complex is considered to have a monomeric tetrahedral structure. It reacts with p-cresol to give [Cu(O–C6H4–CH3-P)(tdpme)] and also with highly active hydrogen compounds, methyl cyanoacetate and methyl nitroacetate, to give [Cu{CH(CN)CO2CH3}(tdpme)] and [Cu{CH(NO2)CO2CH3}(tdpme)], respectively. However, moderately active hydrogen compounds, such as acetonitrile, dimethyl malonate, and nitromethane, do not react with [Cu(C≡CPh)(tdpme)]. The reactivities of the complex with active hydrogen compounds are discussed in correlation with the pKa values of the latter compounds.
Ligand Isotopic Exchange of Tris(acetylacetonato)germanium(IV) Perchlorate in Organic Solvents
Authors: Nagasawa Akira , Saito Kazuo
Published: July 2006

The ligand isotopic exchange between tris(acetylacetonato)germanium(IV) perchlorate and acetylacetone[14C] has been studied in 1,1,2,2-tetrachloroethane (TCE), nitromethane (NM), and acetonitrile (AN), at 100–120°C. In these solvents, the rate formula was R=k[H2O][complex]; the concentrations of the complex, free ligand, and water in solution were in the ranges from 0.01 to 0.1 mol dm−3. The activation enthalpies and entropies for the k’s are 105, 98, and 90 kJ mol−1; and −25, −53, and −69 J K−1 mol−1, in TCE, NM, and AN, respectively. Influence of acid and base concentrations, and deuterium isotope effect on the rate in AN suggest that the rate controlling step of the exchange is governed by the ease of the proton transfer between the leaving and the incoming acac− in an intermediate.
Flameless Atomic Fluorescence Spectrometry of Mercury by Dispersive and Nondispersive Systems in Combination with Cold-vapor Technique
Authors: Nakahara Taketoshi , Tanaka Toshiaki , Musha Sôichirô
Published: July 2006

An atomic fluorescence spectrometer with dispersive and nondispersive systems has been designed and constructed. A flameless atomic fluorescence spectrometric method with the newly constructed spectrometer is described for the determination of mercury at the nanogram level. Mercury is reduced by tin(II) chloride and released from solution by a stream of argon into a quartz fluorescence cell. The fluorescence signal is measured by dispersive and nondispersive systems. Linear analytical working curves covering the mass range of mercury from the detection limits to approximately 10 and 1 μg have been established with dispersive and nondispersive systems, respectively. With the nondispersive system a detection limit of 0.003 ppb or 0.05 ng of mercury could readily be obtained. The present method was satisfactorily applied to the determination of mercury in wastewater samples.
Reactions of Bis(acetylacetonato)oxovanadium(IV) with Phenol and Its para-Substituted Derivatives
Authors: Taguchi Hiroshi , Isobe Kiyoshi , Nakamura Yukio , Kawaguchi Shinichi
Published: July 2006

Bis(acetylacetonato)oxovanadium(IV) reacts with phenol or its para-substituted derivatives in methanol, affording stable adducts with the composition of VO(acac)2(p-XC6H4OH), where X=H, NO2, CHO, COOH, Cl, or CH3. The magnetic and spectral data reveal that these are vanadium(IV) complexes containing the phenol as a neutral ligand. They show an unusually low ν(V=O) frequency of ≈900 cm−1 as compared with the value of 1000 cm−1 for the parent complex, and are presumed to have a polymeric structure with an infinite chain of V=O…V=O…. The phenol is connected by a hydrogen bond to one oxygen atom of an acetylacetonate ligand. The behavior of the complex in solution is also discussed. The addition of 1,10-phenanthroline or 2,2′-bipyridine to a reaction mixture of VO(acac)2 and nitrophenols results in phenolato complexes VO(OC6H5−nXn)(acac)(phen or bpy), where X=NO2 and n=1, 2, or 3. Two isomers of VO(OC6H2(NO2)3)(acac)(bpy) are isolated and characterized.
Photoaddition Reaction of 9,10-Phenanthrenequinone with Alicyclic Olefins. Product Distribution
Authors: Maruyama Kazuhiro , Iwai Tatsuaki , Naruta Yoshinori , Otsuki Tetsuo , Miyagi Yo
Published: July 2006

The phtoaddition reaction of 9,10-phenanthrenequinone (1) with several alicyclic olefins (6) has been investigated. In addition to the expected products, dihydrodioxin(2) and keto oxetane (3), the hydroxydihydrofuran derivative (4, 5) were found. Product distribution was shown to be deeply dependent on the structure of the olefins. Product 4 has been shown to be produced via the photorearrangement of 3.
Reduction of Acetals with TiCl4–LiAlH4
Authors: Ishikawa Hiroshi , Mukaiyama Teruaki
Published: July 2006

The reduction of dialkyl acetals derived from aromatic aldehydes and ketones with TiCl4–LiAlH4 in THF or diethyl ether at room temperature afforded the coupling products, pinacol ethers or olefins, in high yields. On the other hand, when acetals derived from aliphatic aldehydes and ketones were treated with TiCl4–LiAlH4 in diethyl ether, the reductive dealkoxylation took place and the corresponding ethers were isolated in good yields. As to the reaction mechanism we propose that Ti(II) is the reactive species in reductive coupling reaction of acetals derived from aromatic aldehydes and ketones, and that Ti(0)–H2AlCl complex may be the reactive species in reductive dealkoxylation of acetals derived frcm aliphatic aldehydes and ketones.