bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction of 1,1-Diiodoethane with Copper Powder in the Presence of Olefins and/or Alkylbenzenes
Authors: Kawabata Nariyoshi , Yamagishi Nobuyuki , Yamashita Shinzo 
Published: July 2006

Abstract
The treatment of 1,1-diiodoethane with copper powder in the presence of 1-heptene gave a 1.3 : 1 mixture of cis- and trans-1-methyl-2-pentylcyclopropane in 11% yield. The treatment in the presence of cyclohexene gave a 1 : 1.7 mixture of endo- and exo-7-methylbicyclo[4.1.0]heptane in 32% yield, together with 1-ethylcyclohexene in 8% yield, which was shown to be derived mainly from isomerization of the endo-isomer. These reactions were concluded to proceed via organocopper intermediate rather than free methylcarbene. The treatment of 1,1-diiodoethane with copper powder in the presence of alkylbenzene gave a mixture of o- and p-ethyl(alkyl) benzene contrary to the corresponding reaction of methylcarbenoid of zinc which gave cycloheptatriene derivatives.
ESR Studies of Dibenzenesulfenamidyl Radicals
Authors: Miura Yozo , Makita Noboru , Kinoshita Masayoshi 
Published: July 2006

Abstract
Dibenzenesulfenamidyl radicals (2) were generated by the oxidation of dibenzenesulfenamides (1), and their ESR and visible spectra were measured. The ESR spectra were split into a 1 : 1 : 1 triplet by the interaction with the nitrogen nucleus (aN=11.26–11.49 G); in some spectra, each of the triplet was further split by the interaction with the ring protons (ao−H=ap−H=0.48–0.70, am−H=0.18–0.22 G). The g-values lay in the range of 2.0080–2.0083. From the results, it was concluded that the unpaired electron is distributed mainly on the nitrogen and the two sulfur atoms. Kinetic studies of the decay of 2 indicated that 2 decays with second-order kinetics and is not sensitive to the atmospheric oxygen.
Nature of Catalytically Active Sites over Solid Acids. II. Relationships between Acidic Properties of Silica–Alumina and Its Catalytic Activities for Olefin Polymerization
Authors: Take Jun-ichiro , Ikeda Masanori , Yoneda Yukio 
Published: July 2006

Abstract
The influences of the degree of hydration of a silica–alumina surface on its Bronsted or Lewis acid content and on its catalytic activity for cis-2-butene polymerization were investigated at 30 °C as a function of the evacuation temperature. The raise in the evacuation temperature, i.e., the decrease in the degree of hydration, gave rise to an increase in both the Lewis acid content and the catalytic activity but to a decrease in the Bronsted acid concent. A good linear relationship, which could not be extrapolated through the origin, was found between the Lewis acid content and the catalytic activity. Thus, the conclusion is drawn that only strong Lewis acid sites are active in olefin polymerization on silica–alumina at low temperature.
Condensed State Spectra and Phase Transitions of Charge Transfer Autocomplexes
Authors: Freimanis J\={a}nis , M\={a}lmanis Andrejs , Dr\={e}geris J\={a}nis 
Published: July 2006

Abstract
The results of a spectroscopic study of super-cooled melts and crystalline layers of charge-transfer autocomplexes are reported. Samples obtained by sublimation in vacuo or by melting of the complex between transparent plates undergo a “liquid-solid” phase transition. Amorphous films produce absorption bands identical with those obtained from solutions, Whereas crystalline layers are colored depending on intermolecular CT interaction. In some cases transparent crystalline films with pronounced optical anisotropy were obtained.
Kinetic Studies on the Decolorization Reaction of Rosaniline in Aqueous Acidic Medium
Authors: Sinha Sudhir K , Katiyar Sarvagya S 
Published: July 2006

Abstract
The reaction responsible for the decolorization of rosaniline in acid medium has been studied spectrophotometrically. The rate-determining step has been found to be the reaction of the protonated dye cation with water molecule. Kinetic data have been analyzed on the basis of rate equations which were derived considering the complete protolytic scheme involving all the steps of the reaction of rosaniline in acid and alkaline media. The rate constant k1 for the ion-molecule reaction has been found to be independent of the dye concentration and hydrogen ion concentration. The apparent rate constant k at various hydrogen ion concentrations has been utilized for calculating the equilibrium constant for the fast protonation step. Effect of ionic strength in the range 0–0.27 indicates no substantial effect on the rate constant k1. Anomalous solvent effects were obtained suggesting the solvated nature of the reactants. The average energy of activation for the reaction of rosaniline in aqueous medium corresponded to 10.52 kcal. Chemical and kinetic evidence has been presented to prove the participation of water molecule in the rate-determining step.
Emission Spectra of the Vinyl Polymers with Pendant Phenanthryl Groups
Authors: Itaya Akira , Okamoto Ken-ichi , Kusabayashi Shigekazu 
Published: July 2006

Abstract
The emission properties of 9-ethylphenanthrene (EPh), poly(9-vinylphenanthrene) (PVPh), poly(9-phenanthryl methacrylate) (PPhMA), and poly[2-(9-phenanthryl)ethyl vinyl ether] were investigated in solution. These vinyl polymers showed no clear excimer fluorescence in the longer-wavelength region. Both the fluorescence quantum yield and the lifetime of PVPh decreased largely with an increase in temperature at higher temperatures. This suggests that PVPh forms an excimer which has a low fluorescence quantum yield. The fluorescence properties of PPhMA and PPhEVE, in which Ph chromophores are widely spaced on the skeletal chains, indicated little interaction between neighboring Ph chromophores in the singlet state. This results from the nature of Ph, in whith it is difficult to form an excimer. The phosphorescence spectrum and its lifetime of PPhEVE indicated a presence of a weak interaction between neighboring Ph chromophores in the triplet state. PVPh and PPhEVE showed a delayed fluorescence resulting from a T-T annihilation between two migrating triplet excitons.
The Position Dependence of the SCF Screened Potential in Several Pseudo-Jahn-Teller Nonbenzenoid Aromatic Hydrocarbons
Authors: Koyanagi Tsuguo , Yamaguchi Hiroyuki 
Published: July 2006

Abstract
The SCF screened potentials of pentalene, heptalene, and s-indacene were calculated by using the SCF screened potential MO CI method. The characteristics of the screened potential in the nuclear arrangement belonging to the lower molecular symmetry group, C2h, are similar to those of the polyene.
Effect of Pressure on Interfacial Tension between Oil and Water
Authors: Matubayasi Norihiro , Motomura Kinsi , Kaneshina Shoji , Nakamura Makoto , Matuura Ryohei 
Published: July 2006

Abstract
The interfacial tension of hexane, octane, carbon tetrachloride and benzene against water was measured as a function of pressure up to 150 MPa at 303.15 K, using a newly designed apparatus. The interfacial tension showed definite increase with pressure and positive volume change was found on interface formation.
The Crystallization of Pb5Si3O11 from the Glass in the PbO–SiO2 System
Authors: Hasegawa Hiroshi , Shimada Masahiko , Kanamaru Fumikazu , Koizumi Mitsue 
Published: July 2006

Abstract
A new compound, Pb5Si3O11, is prepared by the crystallization of the glass in the PbO–SiO2 system. Pb5Si3O11 has an orthorhombic symmetry, and its lattice parameters are determined to be a0=9.93 Å, b0=8.31 Å, and c0=34.4 Å.
The Crystal Structure of Nitratotriaquo(2,2′-bipyridine)copper(II) Nitrate [Cu(NO3)(H2O)3(bipy)]NO3
Authors: Nakai Hisayoshi , Ooi Shun’ichiro , Kuroya Hisao 
Published: July 2006

Abstract
The crystal structure of the title compound has been determined from three-dimensional X-ray data. The crystal is composed of the nitrate anions and the distorted-octahedral [Cu(NO3)(H2O)3(bipy)]+ cations, where the nitrato-groups act as a monodentate ligand and the three coordinated water molecules occupy a facet of the octahedron.
Carbonylation Reaction of Isoprene Catalyzed by Palladium(II) Acetate and Triphenylphosphine
Authors: Tsuji Jiro , Yasuda Hideyuki 
Published: July 2006

Abstract
The carbonylation reaction of isoprene in alcohol catalyzed by palladium(II) acetate and triphenylphosphine gave 4-methyl-3-pentenoate selectively in a moderate yield. Unlike butadiene, no dimerization-carbonylation of isoprene to give C11 esters took place.
Microdetermination of Furfural Using: Bromine Monochloride
Authors: Shukla V K S , Shukla S 
Published: July 2006

Abstract
A simple micro procedure for the estimation of furfural with bromine monochloride has been presented. A 2–10mg sample dissolved in distilled water is reacted with a known excess of bromine monochloride in acetic acid in an ice bath, and the excess reagent is back titrated iodometrically. The maximum deviation in the results is ±0.90%.
The Synthesis of 4-Acetylaminoimidazole-5-sulfonamide and 1-Acetyl-5-acetylimidazole-4-sulfonamide
Authors: Robinson B , Zubair M Uppal 
Published: July 2006

Abstract
The synthesis of mono- and di-, N-acetyl derivatives of 5-aminoimidazole-4-sulfonamide, from 5-nitroimidazole-4-sulfonamide, as analogues of 5-amino-1′-ribonucleotyl)imidazole-4-carboxamide, is described.
Improvement of Zone-melting Apparatus: A New Apparatus with a High-precision Heater-temperature-controlling Mechanism
Authors: Ishizuka Yasuko 
Published: July 2006

Abstract
A new zone-melting apparatus with a high-precision heater-temperature-controlling mechanism has been designed and constructed. The apparatus can control the width of several melting zones at an equal temperature and thus can obtain smooth concentration profiles after zone refining. The effect of zone refining with this apparatus was examined with fair success, using phenanthrene and naphthalene as samples.
Mössbauer Absorption Spectra of 119Sn in Single Crystals of (CH3)2SnF2 and (CH3)2SnCl2
Authors: Negita Hisao , Boku Ryukei , Nakamura Makoto , Ichiba Sumio 
Published: July 2006

Abstract
The Mössbauer absorption spectra of 119Sn in single crystals of (CH3)2SnF2 and (CH3)2SnCl2 have been studied as a function of the orientation angles of the incident unpolarized gamma-ray beam with respect to the crystal axes, taking the absorber thickness effect into account. The analysis of the intensity ratios of the quadrupole splitting doublet yields the asymmetry parameter (η) and the orientation of the principal axes of the electric-field gradient with respect to the crystal axes. The value of η in (CH3)2SnCl2 at 135 K was about 0.4, less than the value published previously. The sign of the 119Sn quadrupole coupling constant (e2qQ) in these compounds was found to be positive, as has been reported before.
Excited States of N-Salicylidenealkylamines Chelating to Zinc(II)
Authors: Ohno Takeshi , Kato Shunji , Takeuchi Akira , Yamada Shoichiro 
Published: July 2006

Abstract
For several different forms of N-salicylidenealkylamines (Schiff bases), the absorption and emission spectra, and the yields, lifetimes, and polarizations of the emissions were measured. The neutral Schiff bases exist in two forms, the enolimine and the ketoamine, in an alcoholic solution. All anions of the Schiff bases emit a moderate fluorescence at room temperature and a strong fluorescence and a very weak phosphorescence at 77K. Chelating to Zn2+ and Be2+, they strongly emit a fluorescence and phosphorescence similar to those of the free anions. In the bis-bidentate complexes, the phosphorescence increases and the fluorescence decreases compared to those of the mono-bidentatc complexes—this change in the emission yields may be due to the increase in the intersystem crossing rate, enhanced by an interaction between the ligands perpendicular to each other.
Reaction of Pyridine Bases with Carboxylic Acids in Benzene
Authors: Hirose Katsumi , Tanaka Motoharu 
Published: July 2006

Abstract
The reaction of pyridine bases with aliphatic monocarboxylic acids has been studied by means of the partition method. Partition was carried out at 25 °C between benzene and 0.10 mol dm−3 (Na, H) ClO4 aqueous solution, the total concentration of pyridine base and that of carboxylic acid being less than 2×10−2 mol dm−3 and 1.0 mol dm−3, respectively. Both (1:1) and (1:2) complexes (base to acid ratio) are formed in benzene, (1:3) complex being additionally formed only for 2,4,6-trimethylpyridine. A linear free energy relationship is observed between the formation of the (1:1) and (1:2) complexes and the protonation in water of the corresponding bases except for sterically crowded 2,6-dimethyl derivatives of pyridine. The structure of the (1:2) and (1:3) complexes is discussed.
Studies of the Ruthenium Complexes. XIII. Kinetic Studies of Electrontransfer Reactions between Aquapentaammineruthenium(II) and Halopentaammineruthenium(III) Comlexes
Authors: Ohyoshi Akira , Yoshikuni Kenichiro , Ohtsuyama Hidetoshi , Yamashita Tomohisa , Sakaki Shigeyoshi 
Published: July 2006

Abstract
Kinetic measurements of the electron-transfer reactions from Ru(OH2)(NH3)52+ to RuX(NH3)52+, where X=Cl, Br, and I, have been made in aqueous solutions. The reaction rate is independent of the hydrogen-ion concentration, while it is greatly influenced by the ionic strength of the reaction solution. The rate constants were determined to be 147, 172, and 293 M−1s−1 for the reaction systems of chloro- bromo- and iodopentaammineruthenium(III) ions respectively at 25 °C in a solution with an ionic strength of 0.0944 M. The activation parameters, (ΔH\eweq kcal mol−1, ΔS\eweq cal K−1 mol−1), were (19.4, 16), (18.9, 15), and (11.2, −10) respectively, for the same systems. From the facts that the reaction rate decreases in the order of I&gt;Br&gt;Cl and that the ionic strength of the solution strongly affects the reaction rate, it may be concluded that the present electron-transfer reactions proceed by means of an outersphere-type mechanism.
A Study of the Structures of Aluminum Complexes with Isopropoxy and Methyl Groups Using Pulsed NMR and Chemical Ionization Mass Spectrometry
Authors: Uetsuki Masao , Fujiwara Yuzuru 
Published: July 2006

Abstract
The structures of aluminum complexes formed by the reaction of aluminum isopropoxide with trimethylaluminum was investigated by measuring the spin-lattice relaxation times, T1 for 1H and T1* for 27Al. The motion of the ligand of the complexes reflected upon the value of T1, which was about twice as long at the terminal position as at the bridge position, and decreased with increasing molecular weight. Coordination symmetry about the aluminum nucleus of the complexes governed the value of T1*, which was about ten times as long at the center of the tetrameric complexes as at the wing of the dimeric complexes. The 13C NMR signals of the isopropoxy group varied with the configuration of the ligands, while those of the methyl group were either broad or not observable. Chemical ionization mass spectra of the complexes supported the tetrameric and the dimeric structures determined from the results of NMR measurements.
Polymer-supported Trichlorotitanium(III) Complexes and Their Dioxygen Adducts
Authors: Chimura Yasuo , Beppu Masazo , Yoshida Satohiro , Tarama Kimio 
Published: July 2006

Abstract
Various polymer-supported trichlorotitanium(III) (TiCl3) complexes were prepared in pyridine or THF from TiCl3 and copolymers composed of 4-vinylpyridine (10, 20, and 65 mol%), divinylbenzene (0 and 20 mol%), and styrene. The ESR technique was employed for structural studies of titanium(III) species and their dioxygen adducts contained in the supported complexes. The supported complexes contained, as titanium(III) species, mainly (&gt;88%) mixtures of TiCl3(pyr)nL3−n (n=1, 2, and 3), where pyr is a pyridyl group of the supports and L is a molecule of the solvents used in preparation. The relative amounts of the species having smaller n values increased with cross-linking, with a decrease in the content of pyridyl groups, and with pretreatment with tetra-chlorotitanium(IV) (TiCl4). On exposure to oxygen the supported complexes gave two or three kinds of dioxygen adducts (Ti(IV)–O2−) characterized by g1 the principal g value along the axis of O–O bond. The g1 values of three dioxygen adducts α, β and γ were 2.027–2.028, 2.022–2.024, and 2.017–2.018, respectively. The probable structures of α, β, and γ, when L is THF, are [TiCl2(pyr)3(O2)]Cl, TiCl3(pyr)2(O2), and TiCl3(pyr)L(O2), respectively, their precursors being the titanium(III) species having the n values of 3, 2, and 1, respectively.
Peptides. VI. Some Oxime Carbonates as Novel t-Butoxycarbonylating Reagents
Authors: Itoh Masumi , Hagiwara Daijiro , Kamiya Takashi 
Published: July 2006

Abstract
Several t-butoxycarbonyl derivatives of oximes were prepared through the corresponding oxime chloroformates. Of these, diethyl (t-butoxycarbonyloxyimino)malonate and 2-(t-butoxycarbonyloxyimino)-2-phenylacetonitrile were utilized for the preparation of t-butoxycarbonylamino acids under various conditions. The results are summarized in a table.
The Reactions of Carbonimidoyl Dichlorides with Metal Thioacetates, Acetates, Thiocyanates, and Selenocyanate
Authors: Tanaka Sakuya , Uemura Sakae , Okano Masaya 
Published: July 2006

Abstract
The reactions of carbonimidoyl dichlorides with potassium thioacetate and thiocyanate in tetrahydrofuran afford the corresponding isothiocyanates. Similarly, the reaction with potassium selenocyanate gives isoselenocyanates. Thallium (I) acetate reacts with phenylcarbonimidoyl dichloride with greater facility than potassium acetate to give a mixture of phenyl isocyanate and acetanilide in which the latter is predominant. A displacement of one chlorine atom in the carbonimidoyl dichlorides by a SAc, OAc, SCN, or SeCN group, followed by elimination of AcCl or CNCl, has been proposed as a reasonable reaction path.
Extractive Spectrophotometric Determination of Mercury with Thiobenzoylacetone; Analysis of Waste Water
Authors: Murti M V R , Khopkar S M 
Published: July 2006

Abstract
Thiobenzoylacetone was used for the extraction and spectrophotometric determination of mercury(II). The complex quantitatively extracted at pH 4.0 with 10 ml of 0.001 M reagent in benzene. After removing the excess of the reagent with the buffer solution of pH 12.0, the complex was measured at 345 nm against reagent blank prepared similarly. The system adhered to Beer’s law in the concentration range of 0.6 to 12.1 μg of mercury per ml. The molar extinction coefficient was 1.7×104 and the sensitivity was 0.011 μg/cm2. The complex was stable for 48 h. The extraction was quantitative within 10 min of equilibbrium. It was possible to determine mercury in the presence of a large number of ions (1 : 1000). The method was found to be applicable to the analysis of waste water from chloro-alkali industries.
Benzoyl-β-alaninato Nickel(II) Complexes. The Amino Effect on the Amino Acid Coordination around the Nickel Ion
Authors: Marcotrigiano Giuseppe , Menabue Ledi , Pellagani Gian Carlo 
Published: July 2006

Abstract
A compound of the type Ni(Bz-β-ala)2·2H2O (Bz-β-ala=benzoyl-β-alaninate anion) and its amine adducts of the type Ni(Bz-β-ala)2Bn·xH2O (n=1; B=piperazine (pipz), 1,10-phenanthroline (o-phen) and x=2; n=1, B=2,2′-bipyridine (2,2′-bpy) and 4,4′-bipyridine (4,4′-bpy) and x=4; n=2, B=N-methylpiperazine (CH3-pipz), morpholine (morph), pyridine (py), 3-methylpyridine (3-pic) and 4-methylpyridine (4-pic) and x=2; n=3, B=en, and x=0) were prepared. Each complex was characterized by elemental analysis, solid spectroscopy and magnetic moment. All the complexes are six-coordinated and the presence of NiO6 and NiN6 chromophores for Ni(Bz-β-ala)2·2H2O and Ni(en)3(Bz-β-ala)2 complexes respectively and of NiO4N2 chromophores for the amine adducts is suggested. In all the complexes the amino acid appears to act as a bidentate ligand toward the carboxyl group. A ligand field strength in the aromatic heterocyclic amine adducts was found greater than in the aliphatic heterocyclic amine adducts. The amine adducts complexes appear to dissociate in solution with a change of the donor site, without changing in the stereochemistry, around the nickel ion.
The Effect of Urea on the First and Second CMC’s of Aqueous Solutions of Sodium and Lithium Dodecyl Sulfates
Authors: Kodama Michiko , Boku Ryukei , Ishida Toshio , Miura Masaji 
Published: July 2006

Abstract
The effect of urea on the 1st and 2nd CMC’s of aqueous solutions of sodium and lithium dodecyl sulfates was investigated by the measuments of electric conductivity. The results were discussed in terms of the breaking effect of urea on the water structure not only around the hydrocarbon chains, but also around the counter ions of these surfactants.
Hydrogen-Deuterium Exchange Reaction via β-Sulfinyl Carbanion. Neighboring Sulfur Participation in Carbanion Formation
Authors: Koyanagi Tohru , Hayami Jun-ichi , Kaji Aritsune 
Published: July 2006

Abstract
The rate of base-catalyzed H-D exchange reaction of substituted cyclopropanes and cyclohexanes containing sulfur atom at the β-position of reaction center was investigated. Neighboring sulfur participation in stabilization of the carbanion was suggested in the case of ethyl trans-2-(phenylthio)cyclopropanecarboxylate.
The Action of Malononitrile and Ethyl Cyanoacetate on Diphenylcydopropenone
Authors: Agranat Israel , Boyd Gerhard V , Wirt Mark A 
Published: July 2006

Abstract
Diphenylcydopropenone reacts with malononitrile in the presence of ethanolic sodium methoxide to yield, after acidification, (E)-1,1-dicyano-2-hydroxy-3,4-diphenyl-1,3-butadiene (1a); an analogous product, ethyl (2Z, 4E)-2-cyano-3-hydroxy- 4,5-diphenyl- 2,4-pentadienoate (1b), is formed from ethyl cyanoacetate.
Polarography of α-Keto Acids in Aqueous and Nonaqueous Solutions
Authors: Ohmori Mitsuaki , Takagi Masanosuke 
Published: July 2006

Abstract
Phenylglyoxylic acid (I), phenylpyruvic acid (II), and pyruvic acid (III) were polarographically studied in buffer solutions and in DMF. Their reduction waves were reinvestigated in a wider pH range. Cyclic voltammetry showed that most electrode reactions of these acids in acidic pH are irreversible. pH-Dependence of E1⁄2 and limiting current was studied. The observed decrease of the limiting currents of II and III in the strongly alkaline region was attributed to the dissociation of their corresponding enol forms. The i-E curves of these acids in DMF showed successive poorly-defined reduction waves, while those of the corresponding tetraethylammonium salts (TEA salts) were found to be much simpler in shape. A small oxidation wave was also observed with TEA salts of II and III, suggesting the presence of the enol form in DMF. The reduction products of I and its salt in DMF were studied by means of controlled potential electrolysis and NMR-spectroscopy. The electrode reaction mechanism of α-keto acids in nonaqueous solution is discussed, emphasizing the role of the free acid form as a proton-donor and the formation of a radical anion followed by a disproportionation reaction.
The Correlation of Steric Effects and Equilibrium Constants Evaluated from Lanthanoid-induced 1H Shifts in Aniline Derivative–Eu(fod)3 Systems
Authors: Hirayama Masatoshi , Ishida Norio 
Published: July 2006

Abstract
The equilibrium constants, K1 and K2, between a series of o- and N-substituted anilines and Eu(fod)3 in CCl4 were evaluated using a four-parameter analysis of lanthanoid-induced shifts. It was found that the order of magnitudes of the values of K corrected for the effect of the pKa-value well corresponds to the accessibility of the nitrogen lone-pair to the Eu ion on the complexation.