bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Structure of the Cyclodextrin Complex. II. The Crystal Structure of α-Cyclodextrin-Methyl Orange (2 : 1) Complex
Authors: Harata Kazuaki 
Published: July 2006

Abstract
α-Cyclodextrin(α-CDx) forms 2 : 1 complexes with Methyl Orange sodium salt (MONa) and Methyl Orange potassium salt (MOK). The structures were investigated by the X-ray method. The crystals of both complexes belongs to the orthorhombic space group P21212 with Z=2; the cell dimensions are a=22.099(6), b=16.359(3), and c=8.296(1) Å for the MONa complex, and a=22.120(4), b=16.419(4), and c=8.292(1) Å for the MOK complex. Weak streaks were observed between the layer lines in the oscillation photographs around the c* axis. The structures were determined by using 1566 reflections for the MONa complex and 2544 reflections for the MOK complex, and were refined by the least-squares method to the final R-values of 0.11 and 0.10 respectively. α-CDx is a doughnut-shaped molecule with a large cavity. The crystals have channel structures built up by the stacking of α-CDx rings along the c axes. The Methyl Orange anions are located in the channel with a statistical disorder of four different arrangements. The azo group and the benzene ring are included in the cavity of α-CDx, but the dimethylamino and sulfonato groups protrude from the cavity and are in contact with the adjacent α-CDx rings. The azo group is located at the “neck” of the cavity. The sulfonato group is hydrogen-bonded to the primary hydroxyl groups of α-CDx. No significant structural difference was observed between the MONa complex and the MOK complex.
Hybridization in Some Three-Membered Ring Organic Molecules
Authors: Fujimoto Hiroshi , Minato Tsutomu , Inagaki Satoshi , Fukui Kenichi 
Published: July 2006

Abstract
The molecular structures of some simple three-membered ring compounds, cyclopropane, cyclopropanone, ethylene oxide and ethylenimine, were studied by means of the orbital interaction between the fragments of a molecule. The relation between the carbon-carbon distance and the bending angle of the carbon-hydrogen bonds in ethylenic part of the three-membered rings is attributed primarily to the greater extent of mixing of the unoccupied π-like MO of ethylenic fragment into the occupied MO’s of rings. The increase in the bending angle as going from ethylene oxide to cyclopropane is interpreted in terms of the interaction of an occupied π-like orbital with the unoccupied α-like orbital of ethylenic fragment through the overlap with the orbital(s) of the residual part of rings. INDO MO and localized orbital calculations support the orbital interaction scheme. The same conclusion is derived also from the electrostatic theory of molecular geometries.
Infrared Dichroism and Molecular Orientation of Ethyl 2-Hydroxyimino-3-oxo-3-phenylpropionate in Thin Films on Pd Metal Surfaces
Authors: Osawa Masatoshi , Hatta Aritada , Harada Kaoru , Suëtaka Wataru 
Published: July 2006

Abstract
The infrared absorption spectra of ethyl 2-hydroxyimino-3-oxo-3-phenylpropionate, in differently oriented films, formed on Pd metal plates, were measured by using the high-sensitivity reflection method. The thin crystal film A was formed when the solvent was evaporated from the thin liquid film remaining on Pd. On the other hand, the film B resulted from the crystallization of the amorphous solid film which was initially formed on Pd when the liquid film was thick. From the infrared dichroism in the reflection spectra, the molecular orientations in thin films were obtained as follows. In the film A, the ketone C=O and C=N bonds are probably at a pseudo s-cis and are aligned in such a way that the C–C bond connecting the ketone carbonyl group with the C=N group are nearly parallel to the Pd surface. The NO bond is aligned parallel to the metal surface. The ester group is oriented nearly vertical to the metal surface, the C=O bond lying tilted to the surface. In the film B, the ester C=O and NO bonds are aligned nearly perpendicular to the Pd surface, while the ketone C=O bond is not so. The C···C axis of the ester is rather parallel to the surface. The orientation in the thin film A agrees well with the hypothetical chelation model.
Aromatic Nucleophilic Substitution. VII. Electronic Structure of 1,1-Disubstituted 2,4-Dinitronaphthalene Meisenheimer Complexes
Authors: Sekiguchi Shizen , Tsutsumi Kinzo , Shizuka Haruo , Matsui Kohji , Itagaki Takeshi 
Published: July 2006

Abstract
The electronic structures of 1,1-disubstituted 2,4-dinitronaphthalene Meisenheimer complexes were studied by UV-visible and infrared spectrometry and compared with the results calculated by a semiempirical SCF-MO-CI method. The electronic transitions in the complexes were assigned to those of π-π*. Calculated transition energies and intensities agree well with the observed values. The infrared spectra of the complex indicated that the complex is not a charge transfer complex or a radical anion, but an anionic σ complex.
Kinetic Study of Poly(acrylic acid)–Copper(II) Complex Formation
Authors: Nishikawa Hiroshi , Tsuchida Eishun 
Published: July 2006

Abstract
The kinetics of poly(acrylic acid)–copper(II) (PAA–Cu) complex formation has been studied by a relaxation method. It was found that the greater stability of PAA–Cu complex than that of a monomeric analog is due to the increase of forward rate constant (kf(PAA)/kf(GA)=4) and decrease of the reverse rate constant (kr(PAA)/kr(GA)=1/4) in the polymer system. The results are explained in terms of an electrostatic effect of poly electrolyte and a conformational change of the polymer ligand.
The Dissolution of Titanium Minerals in Hydrochloric and Sulfuric Acids
Authors: Imahashi Masayuki , Takamatsu Nobuki 
Published: July 2006

Abstract
Kinetic dissolution experiments of powdered ilmenite and rutile were carried out in sulfuric and hydrochloric acids (0.03–1 M) at temperatures of 40, 65, and 90 °C in order to study the physico-chemical factors and the mechanism for the leaching of titanium and iron from these minerals and rocks under acidic conditions. The dissolution rate of ilmenite was strongly affected by the acidity and temperature of the acid solutions; the rate changes in the H2SO4 solutions were greater than those in the HCl solutions. The dissolution rate of rutile was much slower than that of ilmenite. Ilmenite was decomposed by the dissolution of titanium and iron in a nearly stoichiometric ratio under strongly acidic conditions such as 0.3–1 M. But under milder conditions, such as 0.03–0.1 M at 90 °C, the dissolution rate of titanium dropped rapidly in the initial step and the curved line for iron dissolution was nearly parabolic, suggesting the diffusion of iron through the residual layer of titanium.
Polarographic Anodic Wave of Hydrogen Peroxide in Alkaline Solutions
Authors: Kikuchi Kenji , Murayama Teisuke 
Published: July 2006

Abstract
The anodic reaction of hydrogen peroxide in alkaline solutions has been studied by the polarographic method. Polarograms were recorded in solutions with pH values ranging from 10.0 to 13.5. Hydrogen peroxide in alkaline solutions shows a one-step anodic wave at the dropping mercury electrode. The plot of half-wave potential against pH consists of three segments, each corresponding to a different value of d(E1⁄2)/d(pH): −57 mV for the values of pH below 11.6, −29 mV for the pH range from 11.6 to 13.2, and 0 mV for the values of pH above 13.2 The limiting current is controlled by diffusion. It is concluded that the anodic wave corresponds to the formation of the species [Hg(O2H)(OH)].
Isomerism of the Metal Complexes Containing Multidentate Ligands. VII. The Conformational Analysis of the Isomers of [Co(linpen)]3+
Authors: Yoshikawa Yuzo 
Published: July 2006

Abstract
The conformational analysis of the [Co(dien)2]3+ and [Co(linpen)]3+ (dien=H2N(CH2CH2NH)2H, linpen= H2N(CH2CH2NH)5H) complexes has been carried out. The former, which can exist in three geometric isomers, was selected as a standard for the determination of several parameters in the strain-energy calculation; they were determined so that the calculated geometries of these isomers were almost the same as those obtained from the crystal structure analysis studies. These results were applied to the strain-energy calculation for the latter, [Co(linpen)]3+, which can exist in four geometric isomers. Further, in three of these isomers, some conformational isomers are possible. From the results of the energy-minimized conformational-analysis calculations of these isomers, it has turned out that the assignment of the structures of the configurational and conformational isomers is possible.
Semiempirical Relations in Molecular Liquids. II. Estimation of Thermal Expansivity
Authors: Oono Yoshitsugu 
Published: July 2006

Abstract
A simple method for the estimation of thermal expansivity of the molecular liquid is proposed. Thermal expansivity a can be calculated by
α=T−1φ(y)⁄yφ′(y),
where φ(y)=ph⁄ρkT,y=πρa3⁄6,ph is the pressure of a hard sphere fluid, a the effective hard core diameter of the molecule, ρ the number density, and k, T have their usual meanings. For the molecular liquids consisting of compact molecules, the equation gives a fairly accurate estimation of α, which is practically applicable to the estimation of the density of the liquids at 1 atm at desired temperature.
Stereochemistry of the C and D Rings of C-Nor-D-homosteroids. II. Synthesis of Etiojervane Analogs of Pregnan-3β-ol
Authors: Murai Akio , Nishimura Takeshi , Masamune Tadashi 
Published: July 2006

Abstract
The synthesis of C/D trans- and cis-fused C-nor-D-homo-5α-pregnan-3β-ol 3-acetates (13a and 32) from jervine (1) is described. The configurations of both the compounds and the synthetic intermediates were determined on the basis of chemical and spectral evidence.
Retardation of Autoxidation in the Presence of Water, Alcohols and Carboxylic Acids
Authors: Ukegawa Koji , Kamiya Yoshio 
Published: July 2006

Abstract
The oxidation of alcohols and α-substituted toluenes in water, methanol and acetic acid was studied at 60–70 °C in the presence of 0.040 M AIBN. The rate of oxidation of alcohol, kp/(2kt)1⁄2, considerably increases when the alcohol is diluted with an inert solvent. The rate remarkably decreases with the addition of water, methanol or various carboxylic acids. However in the presence of tetralyl hydroperoxide, viz., when the hydroperoxyl radical is replaced by the tetralyl peroxyl radical, no further inhibition effect due to water, methanol or carboxylic acids is observed. The rate of oxidation of 1,4-cyclohexadiene decreases with the addition of water or acetic acid. However in the presence of 0.20 M tetralyl hydroperoxide, no further inhibition effect is observed. The rate of oxidation of 1-phenylethanol decreases with the addition of benzoic acid but not with that of methylbenzoate. The rate of oxidation of (2-chloroethyl) benzene, ethylbenzene and isopropylbenzene does not decrease with the addition of 0.224 M acetic acid, but that of N,N-dimethylbenzylamine, N,N-diethylbenzylamine, benzyl alcohol, 1-phenylethanol and methyl benzyl ether decreases. It is concluded that hydroperoxyl and alkylperoxyl radicals with α-substituents such as hydroxyl, carbonyl, alkoxyl or amino groups undergo deactivation due to hydrogen bonding with water, alcohols and carboxylic acids.
Liquid-phase Oxidation Catalyzed by Cu(II)–Cl. III. Oxidation of 1,2,3,4-Tetrahydronaphthalene
Authors: Imamura Sei-ichiro , Teramoto Masaaki , Sumi Takao , Aomi Hideki , Teranishi Hiroshi , Takegami Yoshinobu 
Published: July 2006

Abstract
1,2,3,4-Tetrahydronaphthalene was oxidized in the presence of copper(II) acetate in glacial acetic acid. An addition of lithium chloride which formed complexes with copper(II) ion highly accelerated the reaction, and the initiating process was found to be the decomposition of 1,2,3,4-tetrahydro-1-naphthyl hydroperoxide by the copper(II)–chloride ion complexes. However, only about 8% of the decomposition contributed the initiation, and it was suggested that the larger part of the decomposition proceeded through a non-ionic mechanism. Spectrophotometric and ESR experiments suggested that one of the accelerating effects of the chloride ion was due to its action to decompose the inactive copper(II) acetate dimer and form active copper(II)–chloride ion complexes and that the order of the activity of the complexes was CuCl+&lt;CuCl2&lt;CuCl3−,CuCl42−.
The Crystal and Molecular Structure of (+)-1-Bromo-2-hydroxy-2-phenylethyl p-Tolyl Sulfoxide: The Bromohydrin of (+)-trans-β-Styryl p-Tolyl Sulfoxide
Authors: Iwasaki Fujiko , Mitamura Shuichi , Tsuchihashi Gen-ichi 
Published: July 2006

Abstract
The crystal structure of (+)-1-bromo-2-hydroxy-2-phenylethyl p-tolyl sulfoxide, a major isomer formed by the electrophilic addition of BrOH to (+)-trans-β-styryl p-tolyl sulfoxide (1), has been determined by the X-ray diffraction method. The crystal is hexagonal; space group, P62; a=15.61, c=10.82 Å, and Z=6. The final R value is 0.079. A helical chain of the hydrogen bond between hydroxyl and sulfinyl groups (O···O, 2.63 Å) is formed around the threefold screw axis. The absolute configuration has been determined to be Ss, Sc(1), Sc(2) from the Mo Kα anomalous scattering of bromine and sulfur atoms. The bromine atom is gauche to the sulfinyl oxygen across the C(1)–S bond and trans to the hydroxyl oxygen across the C(1)–C(2) bond. Based on the established absolute configuration of the title compound, a mechanism which involves the preferential formation of an intermediary bromonium ion is proposed for the addition of BrOH to 1.
Kinetics on the Formylation of lodobenzene Catalyzed by Palladium(II) Chloride in a Pyridine Solution
Authors: Yoshida Hajime , Sugita Nobuyuki , Kudo Kiyoshi , Takezaki Yoshimasa 
Published: July 2006

Abstract
Benzaldehyde was obtained in good yields by the formylation of iodobenzene with carbon monoxide and hydrogen catalyzed by palladium(II) chloride in a pyridine solution. The effect of following variables on the rate of producing benzaldehyde was examined kinetically : initial catalyst and iodobenzene concentrations, partial pressure of carbon monoxide and hydrogen, and temperature. A probable reaction mechanism via formyl- and benzoyl-palladium(II) intermediates is discussed on the basis of this kinetic study.
Mechanism of the Reaction of Methoxycarbonylcarbene as Revealed by CIDNP. V. Thermal Reaction of Methyl Diazoacetate with Benzyl Ethers
Authors: Iwamura Hiizu , Imahashi Yuzo , Kushida Katsuhiko , Aoki Kiyoshi , Satoh Shiroh 
Published: July 2006

Abstract
When methyl diazoacetate is allowed to react thermally with dibenzyl, benzyl phenyl and benzyl ethyl ethers, insertion into the benzylic carbon–oxygen bonds takes place inter alia to give PhCH2CH(OR)CO2CH3(3, R=PhCH2, Ph, and CH3CH2, respectively). Strongly polarized signals due to the insertion products 3 were observed in the 1H and 13C NMR spectra of the reacting mixture. Application of Kaptein’s rules to the CIDNP signals demonstrates the formation of 3 by the cage recombination of radical pairs ‾PhCH2··CH(OR)CO2CH3 (2). Product analyses by VPC have also been performed and escape products toluene and ROCH2CO2CH3 (4) inherent to the radical pairs were detected. In the reaction with benzyl ethyl ether, 4 (R=PhCH2) without noticeable CIDNP is produced about six times more than 4 (R=CH3CH2). No methyl α-benzyloxybutyrate is formed. The results indicate that the ethyl group is more easily cleaved than the benzyl via a non-radical path. Formation of an ylide intermediate (PhCH2)R\overset⊕O–\overset\ominusCHCO2CH3 (1, R=CH3CH2) followed by the Hoffmann type β-elimination of ethylene is the most reasonable explanation. Homolysis of the same ylide 1 is considered to give the radical pair 2 (R=CH3CH2). A similar process appears to lead solely to radical pairs 2 (R=PhCH2, Ph) in the case of ylides lacking β-hydrogen. The potentiality of this ylide mechanism in the reactions of ethers is discussed.
The Crystal Structure and the Absolute Configuration of (+)-2,3:6,7-Dibenzobicyclo[3.3.1]nona-2,6-diene-4,8-diyl Bis(p-bromobenzoate)
Authors: Kaneda Tsuguhiro , Katayama Chuji , Tanaka Jiro 
Published: July 2006

Abstract
The crystal and the molecular structure of the titled compound was investigated by the X-ray diffraction method. The absolute configuration was determined by the Bijvoet method as 1R4S5R8S.
Reaction of Thiocarbonyl Compounds with Tributylphosphine
Authors: Ogata Yoshiro , Yamashita Mitsuji , Mizutani Makoto 
Published: July 2006

Abstract
The reaction of thiobenzophenone (1) with tributylphosphine (3) gives an oligomer at room temperature, but it gives tributylphosphine sulfide (4), 1,1,2,2-tetraphenylethane, and tetraphenylethylene (6) at 100 °C.
The reaction of thiofluorenone with 3 gives 4, bifluorenylidine (8), and bifluorenyl (9) at room temperature. These possible mechanisms are discussed by carbene intermediates.
ESR Study of γ-Ray Irradiated Potassium Hexacyanocobaltate K3[Co(CN)6]
Authors: Furuta Naoki , Watanabe Tokuko , Fujiwara Shizuo 
Published: July 2006

Abstract
ESR results for γ-irradiated K3[Co(CN)6] in powder and single crystal forms are reported. The main paramagnetic species detected at 77 K were diisocyanide [CoII(CN)4(NC)2]4− and pentacyanocobaltate (II) [CoII(CN)5]3−. On annealing, diisocyanide was lost and pentacyanocobaltate was formed. In Part I the reaction mechanism is discussed from the results of the powdered sample and in Part II the noncollinear structure is presented as the plausible molecular form of diisocyanide from the results of the single crystal.
The Theory of the Reverse Diffusion of Ions in Mixed Electrolyte Solutions and Experimental Results on the HCl–CaCl2–H2O Ternary System
Authors: Nakagaki Masayuki , Kitagawa Shuji 
Published: July 2006

Abstract
Reverse diffusion is the migration of solutes in the direction opposite to that expected from the concentration gradient, that is, from a portion with a lower concentration to that with a higher concentration. This type of diffusion of ions in mixed electrolyte solutions was studied theoretically on the basis of nonequilibrium thermodynamics. For a solution containing two kinds of cations and one kind of anion, it has been concluded that the reverse diffusion occurs when the mobilities of the coexisting ions differ largely, because the effect of the diffusion potential is pronounced in such a case. It has also been concluded that the practical diffusion coefficient of an ion varies linearly with the ratio of the concentration gradient of a coexisting ion to that of the diffusing ion when the average concentration ratio of the ions is fixed. Moreover, the range of the concentration-gradient ratio, where the practical diffusion coefficient is negative, has been determined. These theoretical conclusions were tested experimentally for the HCl–CaCl2–H2O ternary system. The results satisfactorily verified that reverse diffusion actually occurred and that the relationship between the diffusion coefficient and the concentration-gradient ratio was linear, as has been expected.
Solvation Effects on the Electron-Transfer Reaction of TCNQ Anion Radical and 2,3-Dichloro-5,6-dicyano-p-benzoquinone
Authors: Yamagishi Akihiko 
Published: July 2006

Abstract
Rate constants were obtained with a temperature-jump apparatus for the electron-transfer reaction between 7,7,8,8-tetracyanoquinodimethane anion radical and 2,3-dichloro-5,6-dicyano-p-benzoquinone in acetonitrile/ tetrahydrofuran (MeCN/THF) and in acetonitrile/water (MeCN/H2O) mixtures. In MeCN/THF, the forward rate constant (k) was determined in three kinds of mixed solvents: k=(5±2)×109 M−1s−1 (pure MeCN), (2.2±0.2)×109 M−1s−1 (1: 2 MeCN/THF), and (6±2)×108 M−1s−1 (1: 10 MeCN/THF) at 25±2°C. In MeCN/H2O the forward rate constant increases with the square of the H2O concentration in the range of [H2O]=2–10 M; k=k0[H2O]2 with k0=(1.0±0.2)×106 M−3s−1 at 25±2 °C. The results are discussed in terms of the specific solvation and the ion-pairing of ion radicals.
Determination of the Dissociation Constants of Salicylic Acid in Water-Ethanol Mixtures by Modified Conductometric Methods
Authors: Mandal A K , Lahiri S C 
Published: July 2006

Abstract
The dissociation constants of salicylic acid in water and ethanol-water mixtures (8–87.6 wt % of ethanol), have been determined by the modified conductometric method as suggested by Gelb. The results have been checked independently from the plot Λ C vs. 1/Λ of salicylic acid in mixed solvents. Λ°HCIO4 and Λ°salicylic acid have also been determined.
Effect of Solvent on Dipole Moment of Aliphatic Mercaptans
Authors: Srivastava A N , Talesara P R 
Published: July 2006

Abstract
Evidence of donor-acceptor complexes as a result of interaction between thiols and carbon tetrachloride has been obtained from the studies of dipole moment at 30°C. Our polarisation data in other solvents except benzene are new. The results obtained have been discussed in terms of the influence of solvent on dipole moments in the light of general theory of Higasi.
Mass Spectrometric Study of the Primary Processes in Photochemical Reactions. III. Primary Steps in Simple Ketone Photolysis and Mass Spectrum of Acetyl Radical
Authors: Yamashita Shigeru 
Published: July 2006

Abstract
The primary processes of the photolyses of acetone, methyl ethyl ketone, and methyl vinyl ketone have been studied using a high intensity UV light beam and collision-free photochemical reactor incorporated in the ionsource of a mass spectrometer. Photofragment radicals are directly detected from the mass spectrum of the photolyte flow and the primary processes are determined. Mass spectrum of acetyl radical has been obtained in addition to the mass spectra of hydrocarbon free radicals reported in previous papers. As for the ketones investigated, C–C bond rupture between acetyl and the remainder of the molecule is found predominant in the primary process of the photolysis in the region 290–320 nm.
Solvolytic Ring-opening Reacions of gem-Dichloroaziridines in the Presence of Sulfuric Acid
Authors: Sen\={o} Manabu , Shiraishi Shinsaku , Suzuki Yukio , Asahara Teruzo 
Published: July 2006

Abstract
Solvolytic ring-opening reactions of gem-dichloroaziridines in the presence of sulfuric acid were investigated. The reaction products from 1-aryl-2,2-dichloro-3-phenylaziridines varied with the kind of substituent at 3-position of the aziridine ring. 2,2-Dichloro-1,3-diphenylaziridine gave α-chloro-α-phenylacetanilide, 2,2-dichloro-3-methyl-3-phenyl-1-(m-tolyl)aziridine gave N-(m-tolyl)atropamide and 2,2-dichloro-1,3,3-triphenylaziridine gave 3,3-diphenyloxindole. 1-Benzyl-2,2-dichloro-3,3-diphenylaziridine and 2,2-dichloro-1 -phenethyl-3,3-diphenylaziridine gave 4,4-diphenyl-1,2,3,4-tetrahydroisoquinoline-3-one and 1,1-diphenyl-1,2,3,4,5-pentahydro-3-benzazepine-2-one, respectively. It was found that the substituent on C3-carbon determines the mode of reaction.
Asymmetric Hydrogenolysis of Hydrazones. Synthesis of Optically Active α-Alanine
Authors: Kiyooka Syun-ichi , Takeshima Keiko , Yamamoto Hidehumi , Suzuki Kojiro 
Published: July 2006

Abstract
Optically active α-alanines have been synthesized by the asymmetric hydrogenolysis of the chiral hydrazones which were derived from chiral amines and ethyl pyruvate. Reduction of the C=N group in the hydrazones was carried out using PtO2 catalyst in acetic acid at room temperature, followed by hydrogenolysis of the N–N linkage using the same catalyst in 1 M HCl at 100 °C (autoclave). The synthesis using (S)-bornylamine as a chiral reagent afforded l-alanine with optical purity of 46.5%. By using (S)-1,2-dimethylpropylamine as a simple chiral reagent, l-alanine was also obtained with optical purity of 32.2%. It has become apparent that the synthesis using (S)-alkylamine gave l-alanine, while d-alanine was obtained by using (S)-α-methylbenzylamine.