bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbene in Rigid Matrix. XI. Temperature and Matrix Effect on Phenylcarbene Processes in Ether and Amine
Authors: Tomioka Hideo , Suzuki Shinji , Izawa Yasuji 
Published: July 2006

Abstract
Product distributions from reactions of phenylcarbene with diethyl or diisopropyl ether or diethylamine were found to be highly dependent on reaction temperature. As temperature decreases, the C–O displacement reaction and N–H insertion are decreased. Concomitantly, primary C–H insertion products markedly increase especially at lower matrix temperatures.
The Cyclic Voltammetry and Cathodic Reduction of Steroidal Homoallylic Nitro Esters. Dimerization vs. Cyclopropane Formation
Authors: Sato Takeo , Komeichi Yoshihisa , Kobayashi Shoichi , Omura Aira 
Published: July 2006

Abstract
The cathodic reduction of homoallylic nitro esters was carried out in DMF–TBAP using platinum electrodes. The reaction was found to be highly dependent on the ester-leaving group: Whereas 6-nitrocholest-5-en-3β-yl acetate (3a) gave a 3,3′-dimer 4, 3β-tosylate 3d gave a cyclosteroid, 6β-nitro-3α,5-cyclo-5α-cholestane (7). 3β-Trifluoroacetate showed intermediate behavior and gave both 4 and 7. Similarly, 6-nitrocholest-5-ene-3β,19-diol 3-acetate 19-tosylate gave 5β,19-cyclosteroid. The cyclic voltammetry was carried out for these and related compounds. A reversible cyclic voltammogram was recorded for 3a, but 3d showed no anodic peak on potential reversal. A possible electron-transfer and the following chemical-reaction mechanism was discussed.
Carbon-Carbon Bond Formation by the Use of Chloroiodomethane as a C1 Unit. III. A Convenient Synthesis of the Mannich Base from Enol Silyl Ether by a Combination of Chloroiodomethane and N,N,N′,N′-Tetramethylmethanediamine
Authors: Miyano Sotaro , Hokari Hiroshi , Hashimoto Harukichi 
Published: July 2006

Abstract
The Mannich dimethylaminomethylation of carbonyl compounds is conveniently carried out via enol trimethylsilyl ethers by a combination of chloroiodomethane (CH2ClI) and N,N,N′,N′-tetramethylmethanediamine (TMMD) in DMSO as the solvent at ambient temperature. The mechanism of the transformation is discussed on the basis of product analysis and 1H NMR spectral studies. The reagent system CH2ClI/TMMD also provides a convenient route to the Eschenmoser’s salt (Me2\overset+N=CH2,\overset−I).
The Interaction of the Tris(2,2′-bipyridine)ruthenium(II) Ion with Poly(p-styrenesulfonate)
Authors: Kurimura Yoshimi , Yokota Hiroshi , Shigehara Kiyotaka , Tsuchida Eishun 
Published: July 2006

Abstract
The interactions of tris(2,2′-bipyridine)ruthenium(II)([Ru(bpy)3]2+) with some polyanions have been studied by means of cation-exchange resins and the luminescence of [Ru(bpy)3]2+. In an aqueous solution of [Ru(bpy)3]2+ in the presence of sodium poly(p-styrenesulfonate)(PSS), the adsorbability of [Ru(bpy)3]2+ on the cation-exchange resins is strongly suppressed by the binding of [Ru(bpy)3]2+ to the polyanion. The relative luminescence intensity of [Ru(bpy)3]2+ in an aqueous solution is enhanced by the addition of PSS. With the addition of sodium chloride to an [Ru(bpy)3]2+/PSS solution, the interaction is impeded by the shielding of the electrostatic potential in the polymer domains by the counter ions. A cooperative interaction between PSS and [Ru(bpy)3]2+ is postulated with a view to accounting for the results. A chemical application of the interaction is demonstrated.
Products and Kinetic Substituent Effects in the Reactions of Diaryldiazomethanes with 2,5-Dichloro-p-benzoquinone
Authors: Oshima Takumi , Nagai Toshikazu 
Published: July 2006

Abstract
Substituted diphenyldiazomethanes[(x-C6H4)2CN2; x=p-OCH3, p-CH3, H, p-Cl] were found to react with 2,5-dichloro-p-benzoquinone at its conjugated C=C and C=O bonds to give bicyclic diones and poly(2,5-dichlorohydroquinone benzhydryl ether)s respectively, obeying the second-order kinetic law. The product ratios of the polyethers to the bicyclic diones increased from 1.1 to 8.1 with the electron-donating ability of the substituents. The individual rate constants were well correlated with the Hammett equation: logk3=−2.15–1.55 σ (r=0.996) and logk4=−2.03–1.85 (σ0+0.515Δ\barσR+) (r=1.00) for the bicyclic diones and polyethers processes respectively. The presence of methanol as a trapping agent stopped the polymerization completely and afforded the methanolysis product, though no essential change was found in the formation of the bicyclic dione.
Kinetic Solvent Effects in the Decomposition of Diphenyldiazomethane with Chloranil and 2,5-Dichloro-p-benzoquinone
Authors: Oshima Takumi , Nagai Toshikazu 
Published: July 2006

Abstract
A kinetic study was made of the reactions of diphenyldiazomethane (DDM) with chloranil and 2,5-dichloro-p-benzoquinone (DCQ) at 30 °C in 20 and 22 aprotic solvents respectively (19 solvents are common). The chloranil reaction gave poly(tetrachlorohydroquinone benzhydryl ether) alone, obeying the second-order kinetic law. On the other hand, the DCQ reaction afforded bicyclic dione and poly(2,5-dichlorohydroquinone benzhydryl ether), also obeying the second-order kinetic law. All these rate constants generally increased with the solvent polarity and decreased with the solvent basicity. The kinetic solvent effects can be interpreted in terms of the effects of the polarity and the basicity of the solvents respectively to the transition and to the initial states. Thus, the multiple liner correlations of the logarithmic rate constants with a suitable function of the polarity and the basicity of the solvents are fairly successful. It was found that the basicity is more pronounced in the chloranil reaction than in the DCQ reaction, whereas the reverse can be said for the solvent polarity. These results were compared to those of the reactions of DDM with 2,3-dichloro-5,6-dicyanobenzoquinone and tetracyanoethylene.
Computation of Amino Acid Sequences of Polypeptides from Masses of Their Constituent Peptide Fragments and Amino Acid Residues Released in Edman-degradation
Authors: Kitagishi Toyoko , Hong Yeong-Man , Takao Toshifumi , Aimoto Saburo , Shimonishi Yasutsugu 
Published: July 2006

Abstract
A computer program (“PROSEQ2”) was designed for determining the amino acid sequence of polypeptides from molecular weights and N-terminal amino acid residues of two or more sets of peptide mixtures obtained from polypeptides by two or more specific cleavage methods, together with 3-phenyl-2-thiohydantoin derivatives of amino acids released from two or more sets of peptide mixtures by Edman-degradation. Computation of sequences of several polypeptides using this program is described.
The Crystal and Molecular Structure of Pikromycin
Authors: Furusaki Akio , Matsumoto Takeshi , Furuhata Kimio , Ogura Haruo 
Published: July 2006

Abstract
The detailed molecular geometry of pikromycin (C28H47NO8) has been examined by means of X-ray crystal analysis. The crystals are orthorhombic, with four molecules in a unit cell with dimensions of a=11.295, b=25.734, and c=10.509 Å; the space group is P212121. 2259 unique intensity data were collected on a four-circle diffractometer with graphite-monochromated Cu Kα radiation. The structure was solved by the Monte Carlo direct method, using the 30 strongest reflections as the starting set; the 215th random phase set led to the correct solution. The R value reached 0.056 by block-diagonal least-squares refinements. The conformation of the fourteen-membered macrolide ring is considerably different from that of (p-bromobenzoyl) pikromycin in the solid state; e.g., the C=C and C=O conjugated double bonds are cisoid in pikromycin, while they are transoid in the derivative. The molecules are held together through two kinds of intermolecular hydrogen bonds, forming a three-dimensional hydrogen-bonded structure.
Polarographic Behavior of 4-Morpholine Carbodithioate and Its Use in the Amperometric Determination of Metal Ions
Authors: Rao A L J , Brar Bikram S , Puri B K 
Published: July 2006

Abstract
Polarographic behavior of 4-morpholine carbodithioate has been studied in various base electrolytes. It gives a well defined, diffusion controlled, reversible with one electron change, anodic wave above pH 9 extending over a fairly wide span of potential, +0.2 V to −0.3 V vs. SCE. The relation between diffusion current and concentration is linear up to 2.7 mM (1 M=1 mol dm−3) of the reagent. The reagent has been successfully applied for the amperometric determination of Bi3+, Cu2+, Ni2+, Te4+, and Zn2+ individually as well as in mixtures like Cu–Zn and Cu–Ni. Conditions have also been developed for the determination of copper, nickel, and zinc in various alloys. The error does not exceed more than ±0.85% in any case. The method is simple, less time consuming and easily adoptable for the micro determination of these metal ions.
Linear Solvation Energy Relationships. 18. Solvent Effects on the Electronic Absorption Spectrum of p-Nitrophenoxide Ion
Authors: Abboud José-Luis M , Taft Robert W , Kamlet Mortimer J 
Published: July 2006

Abstract
A quantitative analysis of the effects of hydroxylic and aprotic solvents on the electronic absorption spectrum of 4-nitrophenoxide anion is described. By means of linear solvation energy relationships, the contributions of solvent dipolarity, polarizability, and hydrogen bonding are assessed. A significant conclusion is that ion-pairing strongly influences the 4-nitrophenoxide ion in aprotic solvents, but not in hydroxylic solvents. In the latter, specific solvation of both the nitro group and the phenoxide ion center are important.
Dimerization Kinetics of Fluoresceine in Aqueous Solution
Authors: Inaoka Wataru , Harada Shoji , Fujii Susumu , Yasunaga Tatsuya 
Published: July 2006

Abstract
Kinetic studies of the dimerization reaction of fluorescein (doubly charged anion) in aqueous solution were performed by the ultrasonic absorption method. The data obtained could not be interpreted by the rate equation derived with the usual viscosity effect assumed for the diffusion process. Rather, an experimental equation was found, which adequately fits the data. Here, the viscosity contribution is kf=kf0⁄ηr, kb=kb0, and K=K0⁄ηr.
X-Ray Structure of (1RS, 5RS, 7SR)-1-Acetoxy-7-cyano-5-methylbicyclo[3.2.0]heptan-2-one, a Photocycloadduct of 2-Acetoxy-3-methyl-2-cyclopenten-1-one and Acrylonitrile
Authors: Furusaki Akio , Abe Katsumi , Matsumoto Takeshi 
Published: July 2006

Abstract
The main product of the photocycloaddition between 2-acetoxy-3-methyl-2-cyclopenten-1-one and acrylonitrile has been found to be (1RS, 5RS, 7SR)-1-acetoxy-7-cyano-5-methylbicyclo[3.2.0]heptan-2-one by means of X-ray crystal structure analysis.
The Thermal Decomposition of Crystalline Antimonic(V) Acid
Authors: Abe Mitsuo , Sudoh Kazufuyu 
Published: July 2006

Abstract
The thermal decomposition of crystalline antimonic(V) acid (C-SbA) was studied by means of DTA, DSC, and DTG. The amount of water evolved from the heated C-SbA was determined by the Karl Fischer method. The material heated in the range of 600–1000 °C is Sb6O13, neither Sb3O6(OH) nor H2Sb12O26. The thermal decomposition of C-SbA consists of four dehydration and two reduction steps up to 1000 °C.
Circular Dichroism Spectra of cis,cis-[Co(OO)(N)2(py)2]+-Type Complexes
Authors: Fujinami Shuhei , Tsuji Kenshi , Musa Ritsuko , Shibata Muraji 
Published: July 2006

Abstract
Four new complexes, cis,cis-[Co(OO)(NH2C2H5)2(py)2]+(OO=CO32−, ox2−, or mal2−) and cis,cis-[Co(ox)(NH3)2(py)2]+, have been prepared and optically resolved. The CD patterns regularly change in the order of carbonato, oxalato, and malonato complexes, the aspect in the change being opposite to that of related cis,cis-[Co(NO2)2(OO)(NH3)2]−-type complexes.
A New Phase of Compound CaMnO2+δ
Authors: Takahashi Koichiro , Yamamura Hiroshi , Muramatsu Kunitaka , Shirasaki Shin-ichi , Suehiro Kensuke 
Published: July 2006

Abstract
A new phase of CaMnO2+δ was synthesized by a wet process, followed by calcining. The structure was determined to be orthorhombic, with these lattice constants: a=5.96, b=14.38, and c=5.72 Å. Phase transformations among CaMnO2+δ compounds were studied in various atmospheres, such as N2, CO2, and air.
Spectrophotometric Determination of Sodium 4-Dodecylbenzenesulfonate with 1-(N-Methylpyridinium-4-yl-azo)-4-(4-diethylaminophenylazo)naphthalene Iodide
Authors: Higuchi Keiro , Shimoishi Yasuaki , Miyata Haruo , Tôei Kyoji 
Published: July 2006

Abstract
A new reagent, 1-(N-methylpyridinium-4-yl-azo)-4-(4-diethylaminophenylazo)naphthalene iodide, can react with sodium 4-dodecylbenzenesulfonate to show a color change in an aqueous phase in the presence of iodide ion. The calibration graph is straight line up to 1.2×10−5 M (1 M=1 mol dm−3); ε=3.25×104 1 mol−1 cm−1 at 580 nm.
Reaction of Nitrostyrenes and 1-Nitrohexane with Sodium Polysulfides and Sodium Hydroxide
Authors: Ogata Yoshiro , Nakagawa Yoshiaki , Inaishi Morio 
Published: July 2006

Abstract
The reaction of β-nitrostyrene with NaOH in refluxing EtOH–H2O (1 : 2) gives benzaldehyde, benzyl alcohol, benzoic acid, phenylacetic acid, β-phenylethyl alcohol, and polymeric materials. On the other hand, the reaction of β-nitrostyrene with Na2S4–NaOH in the same solvent gave acetophenone besides the same products obtained with NaOH. Acetophenone was likewise detected in the Na2S–NaOH and Na2S2–NaOH reactions. 4-Nitrostyrene was also allowed to react with Na2S4–NaOH in EtOH–H2O (4 : 1) to give a small amount of 4-aminoacetophenone. The formation of acetophenones suggests the occurrence of the Michael addition of polysulfide ion and supports our mechanism proposed previously for the reaction of p-nitrotoluene with Na2S4. The reaction of 1-nitrohexane with Na2S4–NaOH, in which the Michael addition is not conceivable, gives the same products as the reaction with NaOH.
The Direct Synthesis of Methyl 2,4-Di-O-benzyl-α-d-xylopyranoside by the Regiospecific Benzylation of Methyl α-d-Xylopyranoside
Authors: Morishima Naohiko , Koto Shinkiti , Kusuhara Chiharu , Zen Shonosuke 
Published: July 2006

Abstract
The regiospecific benzylation of methyl α-d-xylopyranoside with benzyl chloride and sodium hydride produces methyl 2,4-di-O-benzyl-α-d-xylopyranoside in a 70% yield, together with the by-products, methyl 2,3- and 3,4-di-O-benzyl-α-d-xylopyranosides. The structure of the 2,4-di-O-benzyl derivative was confirmed through the alternative synthesis of the 2,3- and 3,4-di-O-benzyl derivatives via the O-isopropylidene and O-cyclohexylidene derivatives of methyl α-d-xylopyranoside.
ESR Spectra of Anion Radicals of 8,8-Dicyanoheptafulvene and Its 4,5-Benzo Derivative
Authors: Ikegami Yusaku , Muramatsu Takashi , Asao Toyonobu 
Published: July 2006

Abstract
The hyperfine splitting constants for the 8,8-dicyanoheptafulvene anion radical generated electrolytically at low temperature indicate that the unpaired spin belongs to an a2 orbital of the group C2v. Its 4,5-benzo derivative gives a stable anion radical by reduction with alkali metals. The odd electron belongs to a b2 orbital.
Electrohydrodynamic Dissipative Structure in Unipolar and Bipolar Injection Cases
Authors: Aikawa Yoshihiro , Shimoda Haruhisa , Kobayashi Kenkichiro , Takahashi Akira , Takeda Shuzaburo , Sakata Toshibumi , Sukigara Mitsunori 
Published: July 2006

Abstract
An electrohydrodynamic dissipative structure appearing in a suspension system of TiO2 particles in organic solvents is analyzed from a viewpoint of thermodynamics. This analysis gives rather a general explanation for electrohydrodynamic instability caused by unipolar injection and for that caused by bipolar injection. Dimensionless parameters which are the criteria of the hydrodynamic instability are given as R=εV⁄ημ and R=ε2V2⁄nqμηc2 respectively for the former and latter cases. The lattice constant of the hexagonal dissipative structure is derived to be proportional to the thickness of the liquid layer.
Electrolytic Reduction of Carbon Dioxide at Mercury Electrode in Aqueous Solution
Authors: Hori Yoshio , Suzuki Shin 
Published: July 2006

Abstract
Cathodic reduction of carbon dioxide at a mercury pool electrode was investigated in aqueous solutions of NaHCO3, NaH2PO4–Na2HPO4, NaCl, NaClO4, Na2SO4, LiHCO3, and KHCO3 as well as their combinations. The reaction product was confirmed to be HCOO− by a qualitative spot test. HCOO− was quantitatively analyzed by a permanganate titration. The partial current densities of HCOO− formation (ic) and H2 evolution (iH) were calculated. In the present paper, relationships between electrode behavior and solution properties, some of which have been qualitatively described in previous papers, are quantitatively clarified as follows. The electrode potential Ec for constant ic (0.5 mA/cm2) remains constant irrespective of pH and anions in the pH region of 2.4 to 7.8, whereas the potential EH for constant iH (0.5 mA/cm2) varies linearly with a slope of 125 mV/pH. The present experimental results verify Eyring et al.’s presumption that in a relatively high overvoltage region (region 2) the cathodic reduction of CO2 at Hg proceeds with the charge transfer to CO2 as the rate determining step. CO2 reduction and H2 evolution are concluded to proceed independently at the Hg electrode. The dependence of Ec on electrolyte concentration is interpreted in terms of the diffuse double layer theory. The effect of cation species on Ec also is discussed.
New Application of PAS for In Situ Observation of Semiconductor Electrode Surface
Authors: Masuda Hideki , Fujishima Akira , Honda Kenichi 
Published: July 2006

Abstract
The photoacoustic spectroscopic technique was used to study in situ cathodic decomposition of CdS and ZnO semiconductor electrodes and electrochemical deposition of metal ions (Cd2+ and Zn2+) on the semiconductor electrodes.
1H and 19F Nuclear Magnetic Relaxation Studies of Molecular Motion in Solid Fluoroform
Authors: Eguchi Taro , Kishita Michihiko , Chihara Hideaki , Soda Gen 
Published: July 2006

Abstract
Spin-lattice relaxation times of proton and fluorine nuclei in solid CHF3 were measured by the pulsed magnetic resonance technique between 7 and 116K. In 1H resonance, non-exponential recovery of magnetization was clearly observed. T1 data as well as magnetization recoveries were interpreted in terms of intramolecular magnetic dipole interactions between like spins and also between unlike spins, which are modulated by the isotropic reorientation of a whole molecule. A calculation of the temperature dependence of T1 was made by using an activation energy of 17kJ mol−1 and a pre-exponential factor of 1.0×10−16 s for the motion, yielding results in agreement with the present experimental results.
The Adsorption of Amino Acids from Water on Activated Carbons
Authors: Abe Ikuo , Hayashi Katsumi , Kitagawa Mutsuo 
Published: July 2006

Abstract
Freundlich’s adsorption constants of 17 amino acids from aqueous solutions onto an activated carbon have been determined and correlated with various physical constants. A good linear relationship is obtained between the adsorption constants and such physical constants as the molecular refraction and the parachor. The adsorption isotherms of amino acids can be predicted from the molecular refraction or the parachor alone.
UV Absorption Studies of the Pyrolysis of Isobutane in Shock Waves
Authors: Koike Tohru , Morinaga Kihei 
Published: July 2006

Abstract
The UV absorption measurements at 216 nm were carried out for two shock-heated mixtures, 1.5 and 2.0% i-C4H10 diluted in Ar, in the temperature range of 1300–1800 K, and at an atmospheric pressure of about half. From the initial absorption rise attributed to the CH3 growth, the rate constant of the initiation reaction, i-C4H10=CH3+i-C3H7, was evaluated as k=1012.8±0.5exp[−(60.8±4.6) kcal/RT]/s−1. A comparison between the k value so derived and the formerly reported values was made. A computer modeling using a 39-reaction mechanism could reproduce the absorption at the early stage of the reaction at temperatures lower than 1550 K, whereas the modeled absorption was smaller than the measured at much high temperatures. The absorption by C3H5 (allyl radical) must be taken into account in order to lessen this difference.
X-Ray Photoelectron Spectroscopic Study of Highly Conductive Bromine-doped Polyacetylene
Authors: Ikemoto Isao , Cao Yong , Yamada Masamichi , Kuroda Haruo , Harada Issei , Shirakawa Hideki , Ikeda Sakuji 
Published: July 2006

Abstract
The bromine-doped polyacetylenes were studied by X-ray photoelectron spectroscopy. The IR, Raman, and mass spectra were also measured. We find that below the doping content at which the electrical conductivity shows the maximum, bromine content is higher in the surface region than in the bulk. The C ls peak of X-ray photoelectron spectrum is composed of at least two components with the splitting of about 1.7 eV. The relative intensities of two components change with bromine content. The higher-binding-energy component of C ls peak is attributed to positively charged carbon atoms in the metallic domains where dopant is highly concentrated, and the lower-binding-energy component to carbon atoms in the undoped low-conductive domains. The amount of charge transfer in the metallic domain is estimated to be about 0.3|e| per carbon atom. A possible reaction mechanism of bromine with polyacetylene is discussed.
Reduction of Chromium(VI) by Iron(II) Hydroxide in Alkaline Solution
Authors: Aoki Toyoaki , Munemori Makoto 
Published: July 2006

Abstract
Iron(II) hydroxide stoichiometrically reduces CrO42− to chromium(III) in alkaline solutions of pH 8 or above. This reduction was finished in less than one minute even at 5 °C. Although chromium(III) dissolves as CrO2− above pH 9.5, it did not dissolve in the presence of iron(III) hydroxide which had resulted from the oxidation of iron(II) hydroxide.
Determination of Trace Amounts of Iron, Nickel, and Tin in Zircaloys by X-Ray Fluorescence Spectrometry after Coprecipitation with Hexamethyleneammonium Hexamethylenedithiocarbamate
Authors: Yamamoto Yoshikazu , Sugita Michiyuki , Ueda Kazumasa 
Published: July 2006

Abstract
A rapid and precise X-ray fluorescence spectrometry is proposed for the determination of the trace amounts of iron, nickel, and tin in zircaloys. A zircaloy sample was dissolved in a mixture of tetrafluoroboric acid and hydrochloric acid, diluted to a definite volume with water. After the addition of 3 cm3 of 1% (R,R)-tartaric acid solution as an auxiliary chelating agent and 50 μg of cobalt as an internal standard to an aliquot (less than 200 μg of tin) of the solution, the pH was adjusted to 2 with ammonia solution and 3 cm3 of 1% hexamethyleneammonium hexamethylenedithiocarbamate (HMA–HMDC) was added. The resulting HMA–HMDC complexes were collected on a membrane filter and dried. The contents of iron, nickel, and tin in zircaloys were calculated by the calibration curves with the ratios of Kα intensities for each element to that for cobalt. The coefficients of variation (5 results for each metal) were 2.16, 0.63, and 1.52% for 10, 10, and 200 μg of iron, nickel, and tin, respectively. The analytical results of iron, nickel, and tin in zircaloy samples by the proposed method agreed with the certified values.