bluuebunny/crossref_metadata_2025 huggingface dataset:
N-Allylpyrazole as a Ligand. II. The Preparation and Reaction of Some Palladium(II) and Platinum (II) Complexes
Authors: Miyamoto Takeshi , Fukushima Kazuo , Saito Taro , Sasaki Yukiyoshi
Published: July 2006

New complexes of N-allylpyrazole(L) with Pd(II) and Pt(II) have been prepared and characterized; they have the general formulae of MX2L2 and MX2L (X=Cl or Br). IR and 1H NMR studies indicate that the latter complexes are cis-planar-chelate and involve both the pyrazolyl nitrogen and the olefinic group in bonding to the metal, while the former are syn- and anti-trans-planar and contain only uni-dentate pyrazole donor ligands. The treatment of the chelate complex PtCl2L(L=1-(2-methylallyl)-3,4,5-trimethylpyrazole) with donor ligands (L′) such as phosphines, AsPh3, and py displaces the coordinated olefin,forming cis-PtCl2LL′ with a retention of the cis-configuration.
Synthesis of Pseudo-β-Dl-galactopyranose and Pseudo-α-Dl-altropyranose
Authors: Suami Tetsuo , Ogawa Seiichiro , Ishibashi Takashi , Kasahara Isamu
Published: July 2006

Pseudo-β-Dl-galactopyranose and pseudo-α-Dl-altropyranose pentaacetates (10 and 11) were obtained in a seven step reaction starting from Dl-1,2-O-cyclohexylidene-5-deoxy-chiro-inositol (2).
1H-2,3-Benzoxazin-1-ones. II. Action of Amines, Phenylhydrazine, Aluminium Chloride, and Grignard Reagents on 4-Aryl-1H-2,3-benzoxazin-1-ones
Authors: Fahmy A F M , Aly Nawal F
Published: July 2006

4-Aryl-1H-2,3-benzoxazin-1-one on reaction with amines by fusion gave o-aroyl benzamides. With benzylamine in benzene they gave (2-benzylcarbamoyl)-benzophenone oximes, and with phenylhydrazine they gave 1,3-diaryl-1,2-dihydrophthalazin-4-ones. However, with anhydrous AlCl3 (12 mol) in reactive hydrocarbon substrates, they gave the corresponding o-aroylbenzophenone anils. With Grignard reagents they gave the corresponding o-aroyl-triaryl-methanols, which upon cyclization gave 1,1,4-triaryl-1(H)-2,3-benzoxazines.
Nuclear Magnetic Resonance Studies of Bicyclic Thiophene Derivatives. IV. Further Examples of Through-space H–F Coupling
Authors: Hirohashi Toshiyuki , Inaba Shigeho , Yamamoto Hisao
Published: July 2006

Bicyclic thiophene derivatives, 3-methyl-4-(o-fluorophenyl)-2,3-dihydrothieno[2,3-d]-pyrimidin-2-ones (I) and N,5-dimethyl-4-(o-fluorophenyl)-5H-thieno[2,3-c]-pyrrole-6-carboxamides (II), have been prepared. Two sorts of 1H, 19F spin coupling over six bonds attributable to a through-space mechanism have been observed in the 1H NMR spectra of these compounds.
Polarographic Studies on Bipyridine Complexes. IV. The Polarography of the Dicyanobis(2,2′-bipyridine)iron(II) Complex
Authors: Saji Tetsuo , Aoyagui Shigeru
Published: July 2006

Each electron added to the oxidant in the first two reduction waves of a polarogram for dicyanobis(2,2′-bipyridine)iron(II) is concluded to occupy a π*-orbital localized on a bipyridine molecule, on the basis of the number of the reversible waves and the half-wave potential shift caused by the methyl substitution of ligand bipyridines.
Studies of the π→π* Absorption Bands of 1,2-Naphthoquinone
Authors: Kuboyama Akira , Arano Hiroshi
Published: July 2006

The π→π* S–S absorption spectra up to the vacuum UV region of 1,2-naphthoquinone in solutions were obtained. Based on MO calculations, the observed five π→π* bands of 1,2-naphthoquinone are assigned, and the alkyl-group substitution effects on the excitation energy of the longest-wavelength π→π* band are discussed.
Magnetic Susceptibility of Perylene-Iodine Complex
Authors: Kinoshita Minoru , Kanda Hisao , Akamatu Hideo
Published: July 2006

The magnetic susceptibility of a highly conductive 2 : 3 charge-transfer complex of perylene with iodine has been examined as a function of temperature. The paramagnetic susceptibility, which was found to be nearly independent of temperature, is considered to be due only to the perylene cation radical.
The Photoconductivity of Poly(N-vinylcarbazole). VII. The Effect of the Singlet and Triplet Quenchers on the Photoconductivity
Authors: Okamoto Ken-ichi , Oda Norikazu , Itaya Akira , Kusabayashi Shigekazu
Published: July 2006

The singlet quenchers significantly reduce the photocurrents of poly(N-vinylcarbazole) and of brominated poly(N-vinylcarbazole), but the triplet quenchers do not do so at all regardless of the high efficiency of the polymer-to-quencher triplet energy transfer. This result excludes the possibility of the photocarrier generation from the triplet excited state in these polymers.
Rate of Protonation of TCNQ Anion Radical in Water
Authors: Yamagishi Akihiko
Published: July 2006

The protonation of TCNQ, anion radical has been studied with an oxygen-free stopped-flow apparatus. The protonation rate is proportional to the square of TCNQ\ewdot concentration, being independent of the proton concentration. It is suggested that there exists an intramolecular step in which the electronic structure of TCNQ\ewdot changes into another one ready to accept a proton.
The Preparation and the Magnetic Property of Bis(N-o-nitrophenylsalicylideneaminato)copper(II)
Authors: Tokii Tadashi , Ohno Norimitsu , Muto Yoneichiro
Published: July 2006

A synthesis of bis(N-o-nitrophenylsalicylideneaminato)copper(II) is reported. The magnetic properties of the complex and the corresponding p-nitro complex are discussed in terms of the steric effect of the nitro group.
On the Number of Aromatic Sextets in a Benzenoid Hydrocarbon
Authors: Aihara Jun-ichi
Published: July 2006

For a benzenoid hydrocarbon with a single sextet formula, the number of aromatic sextets in it is very close to the number of sextet-type resonance interactions per Kekulé structure.
Radical Anions Derived from 4-Picrylimino-2,6-disubstituted-2,5-cyclohexadiene-1-one
Authors: Manda Eiichiro , Shimura Takehiko
Published: July 2006

4-Picrylimino-2,6-di-t-butyl (or bromo)-2,5-cyclohexadiene-1-ones were synthesized and radical anions were derived from them by one electron reduction with potassium metal. ESR measurement showed that an odd electron exists mainly on the quinone-imine moiety of the radical anion molecule.
Bis(acetylacetonato)metal(II)-Catalyzed Addition of Acceptor Molecules to Acetylacetone
Authors: Uehara Kaku , Ohashi Yoshiyuki , Tanaka Makoto
Published: July 2006

Bis(acetylacetonato)metal(II) (M(acac)2) showed an effective catalytic activity for the addition of various acceptor molecules to acetylacetone to give 3-substituted 2,4-pentanediones.
Enzyme-like Reaction Catalyzed by Flavin-Reduced Keratin Systems. II. Binding Site in FAD-Reduced Keratin Complex
Authors: Takahashi Fujio , Ogasa Tatsuo , Rahman M B
Published: July 2006

In order to confirm the binding site in the FAD-reduced keratin (RK) complex, polarographic and fluorometric studies were carried out and the FAD–RK complex was isolated. An adenine moiety of FAD was found to form a 1:1 complex with RK.
Oxosulfonium Salts. IV. Preparation and Reactions of Methylphenyloxosulfonium Methylide
Authors: Ryoke Katsumi , Minato Hiroshi , Kobayashi Michio
Published: July 2006

Methylphenyloxosulfonium methylide was synthesized, and its reactions with several substrates possessing C=C and C=O bonds were investigated.
Shock Tube Studies of the Rate Constant for Chemical Excitation of Hydroxyl Radicals
Authors: Koike Tohru , Morinaga Kihei
Published: July 2006

The OH(2Σ+2-Π) chemiluminescence in the partial equilibrium region of the H2–O2 reaction in mixtures with H2/O2/Ar=2/2/96, P1=5, 10, 20 Torr was studied in 1250–2000 K incident shock waves. The comparison between the temperature dependence of the OH(2Σ+) emission and that of the computer simulation of the H2–O2 reaction yields the activation energy of the chemical excitation process, assuming the same bi-radical process as former investigators used. The evaluated OH(2Σ+) profile, based on a simulation in which the chemical excitation, radiative, and non-radiative processes are accounted for, depends on the pre-exponential factor of the chemical excitation process. The correlations between the temperature dependence of the evaluated OH(2Σ+) profile and that of the emission profile in the partial equilibrium region gave the pre-exponential factor of the chemical excitation process. Thus, we could estimate the rate constant for O+H+Ar=OH(2Σ+)+Ar to be 1.0×109×exp(−11000 cal⁄RT).
Transition Dipole Interaction and Intermolecular Potential of Carbon Disulfide and Sulfur Dioxide Crystals
Authors: Kuroda Yoshihiro , Machida Katsunosuke
Published: July 2006

The optical active normal frequencies and the heats of sublimation of carbon disulfide and sulfur dioxide crystals have been calculated. The interaction between the transition dipoles associated with the infrared active intermolecular modes has been taken into account by introducing coupling terms between the equivalent coordinates of neighboring molecules. The coupling force constants estimated from the infrared absorption intensities explain the observed trend of the factor group splittings of the ν3 mode of carbon disulfide and the ν1 and ν3 modes of sulfur dioxide. The splitting of the ν2 mode of carbon disulfide has been reproduced by taking account of the long range Coulomb interaction between the atomic charges.
The Structure of the Cyclodextrin Complex. II. The Crystal Structure of α-Cyclodextrin-Methyl Orange (2 : 1) Complex
Authors: Harata Kazuaki
Published: July 2006

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

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

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

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.
Spectral Smoothing in Correlation NMR Spectroscopy
Authors: Ozawa Hiroshi , Arata Yoji
Published: July 2006

A method has been proposed to eliminate a baseline oscillation which appears in a correlation NMR spectrum when one wants to observe peaks on the tilted baseline. An interpolation process in correlation NMR spectroscopy is also discussed which minimizes the number of sampling points.
Kinetic Study of Poly(acrylic acid)–Copper(II) Complex Formation
Authors: Nishikawa Hiroshi , Tsuchida Eishun
Published: July 2006

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

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

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

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

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

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

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

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+<CuCl2<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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Iodination Reactions of Ketones in the Reversed Micellar Systems of Dodecylammonium Propionate in Hexane
Authors: Sen\={o} Manabu , Araki Koji , Shiraishi Shinsaku
Published: July 2006

The iodination reactions of ketones in the reversed micellar systems of dodecylammonium propionate (DAP) in hexane were studied at 25.0 °C in relation to the enzymatic function of aldolase or enolase. The reaction rate in the DAP reversed micellar system is 106–107 times greater than that in the system without DAP, 100 times greater even in comparison with that in DAP aqueous system at pH 6.8. As in the ammonium ion catalyzed reaction in aqueous media, the reaction in the presence of DAP proceeds via ketimine formation between ammonium groups of DAP and acetone and subsequent enolization of ketimine to enamine, which reacts very rapidly with iodine. The catalytic effect of DAP reversed micellar system in each reaction step was discussed. Further, this reversed micellar system shows a marked selectivity for acetone as compared with higher analogs.
α,β-Unsaturated Carboxylic Acid Derivatives. XI. Convenient Synthesis of tert-Butyl 2-Alkoxy- and Hydroxy-2-acetylamino-3-mono- or 3,3-dihaloalkanoates
Authors: Shin Chung-gi , Sato Yoshiaki , Yoshimura Juji
Published: July 2006

It was found that the halogenation of t-butyl 2-acetylamino-3-bromo-2-alkenoate (3) by NBS or NCS gave t-butyl 2-acetylimino-3,3-dihaloalkanoate (6 and 7). The addition of water or several saturated, unsaturated and polyhydric alcohols to the carbon-nitrogen double bond of 6 or 7 was accomplished to give t-butyl 2-acetylamino-2-alkoxy- and hydroxy-3,3-dihaloalkanoate. Similarly, the treatment of t-butyl 2-bromoacetylamino-2-alkenoate in alcohol gave t-butyl 2-acetylamino-2-alkoxy-3-bromoalkanoate, via the addition of alcohol to the imino intermediate (2). The formation mechanism and the structural assignment are discussed.
The Reactions of Polychloroethanes with Phenolate and Benzenethiolate Ions in Dipolar Aprotic Solvents
Authors: Tanimoto Shigeo , Taniyasu Ryôzô , Takahashi Tôru , Miyake Takatoshi , Okano Masaya
Published: July 2006

The reactions of several gem- and vic-polychloroethanes containing 3–5 Cl atoms with PhONa in dimethyl sulfoxide and with PhSNa in N,N-dimethylformamide were examined. Either the mono-, di-, or tetra-substituted compounds of polychloroethylenes were obtained as the main products, depending on the kinds of substrates as well as on the amounts of the bases. The reaction products from polychloroethylenes with 2–4 Cl atoms were also examined under similar conditions for the sake of comparison. Reasonable reaction paths leading to these products were given.
Acid-catalyzed Rearrangements of Tetrahydroasatone and Tetrahydroisoasatone
Authors: Yamamura Shosuke , Terada Yukimasa
Published: July 2006

Tetrahydroasatone (3) and tetrahydroisoasatone (4) both are pretty unstable to various kinds of acid. Action of 6M·HCl–AcOH on the former converted it to the naphthalene-type compound (5) in high yield, whose structure was determined on the basis of its spectral data. In the case of tetrahydroisoasatone, twofold Wagner-Meerwein rearrangements take place, leading to the formation of the isomer-A (9), further rearrangements of which give rise to the bisnordiadamantane-type isomer-B (10a).
The Structures of Two Novel Neolignans, Asatone and Isoasatone
Authors: Yamamura Shosuke , Terada Yukimasa , Chen Yuh-Pan , Hong Mina , Hsu Hong-Yen , Sasaki Kyoyu , Hirata Yoshimasa
Published: July 2006

Isolation and structures of two novel neolignans, asatone (1) and isoasatone (2), are described. The structure of the latter, established by means of an X-ray crystallographic analysis of its dihydroxy derivative, is in full agreement with its chemical and spectral data. From a biogenetic point of view, furthermore, thermal and photochemical reactions of these neolignans and their derivatives were carried out. In particular,asatone was photochemically converted into isoasatone.
Equilibrium and 31P Chemical Shifts of the Adducts of Trialkylphosphines and Isothiocyanates, and Reactions of Triethylphosphine and Benzoyl Isothiocyanate
Authors: Akiba Kin-ya , Yoneyama Toshio , Hamada Hideaki , Inamoto Naoki
Published: July 2006

The adducts (3) of triethylphosphine (1) and several isothiocyanates (2) were prepared. Equilibrium constants of the adducts (5) from tributylphosphine (4) and phenyl (2b), benzoyl (2e), and p-toluenesulfonyl isothiocyanates (2f) were determined in some solvents. The 31P chemical shifts of 5 were measured in DMF, and correlated with Hammett σp constants. Reactions of 3e with 1 and 2e gave phosphonium thiocyanates of 6 and 7, and of 11, respectively. Methylation of 3e gave S-methyl N-benzoylmonothiocarbamate (16).
Studies of Heterocyclic Compounds. VIII. Synthesis and Tautomerism of 2-Hydroxypyrazolo[1,5-a]pyridine
Authors: Ochi Hisao , Miyasaka Tadashi , Kanada Kiyoshi , Arakawa Kiichi
Published: July 2006

2-Hydroxypyrazolo[1,5-a]pyridine (I) was synthesized by reaction of ethyl 2-pyridylacetate (IV) with hydroxylamine-O-sulfonic acid. I was shown to undergo nitrosation, nitration and bromination at C-3 position. Methylation of I with diazomethane gave 2-methoxypyrazolo[1,5-a]pyridine (V), while methylation of I with dimethyl sulfate gave a mixture of V and 1-methyl-1,2-dihydropyrazolo[1,5-a]pyridin-2-one (VI). The enol form was found to be predominant tautomeric species of I in solution. Treatment of I with acetic anhydride afforded 2-acetoxypyrazolo[1,5-a]pyridine (XIII) exclusively. 1-Acetyl-1,2-dihydropyrazolo[1,5-a]pyridin-2-one (XIV) dose not seem to intervene in the formation of thermally stable O-acetylated product (XIII).
A Novel Synthesis of 2-Trialkylphosphonio-1,3-dithiole-4-carboxylates
Authors: Pittman Charles U , Narita Mitsuaki
Published: July 2006

Acetylene carboxylic acids reacted with trialkylphosphine-carbon disulfide ylides to produce fair to good yields of 2-trialkylphosphonio-1,3-dithiole-4-carboxylates (4) at temperatures as low as −20 to −30 °C. The formation of these zwitterionic products, by a prototropic shift in the ylide 3, differs fron the known reaction of acetylenes, such as ethyl propiolate, with carbon disulfide and tributylphosphine to give tetrathiafuvalene derivatives. The structure of these zwitterionic products was confirmed by alkaline hydrolysis, reaction with benzaldehyde, and their IR and NMR spectra. Alkaline hydrolysis of 4 gave the corresponding carboxyl-substituted 1,3-dithioles 7. Treatment of 2-tributylphosphonio-1,3-dithiole-4-carboxylate (4e) with benzaldehyde in the presence of triethylamine resulted in the formation of 2-benzylidene-1,3-dithiole-4-carboxylic acid 8. The methine proton of the 1,3-dithiole ring of 4 in DMSO-d6, appeared at δ 5.41–6.24 as a singlet peak. These methine protons were readily exchanged by deuterium in the presence of methanol-d4, and disappeared from NMR spectra.
The Franck-Condon Factor of the \ ildeA–\ ildeX System of Ammonia
Authors: Kanesaka Isao , Usui Mami , Kawai Kiyoyasu
Published: July 2006

The relative intensity of the \ ildeA–\ ildeX system of ammonia was calculated by using the harmonic and devised harmonic wave functions. The calculated relative intensities do not agree completely with the observed ones. The relative intensity of the vibronic transition was also calculated. However further improvement was not obtained.
Applicability of a Viscosity Formula of Liquid Mixtures to Gaseous Mixtures
Authors: Ishikawa Tetsuya
Published: July 2006

Since 1929, the writer has carried out an elaborate calculation on the viscosity of binary liquid mixtures, using for an ideal mixture the formula

η=\fracη_11+\cfrack_2a_2k_1a_1\cfracz_m1-z_m+\fracη_21+\cfrack_1a_1k_2a_2\cfrac1-z_mz_m

or that in hyperbolic form

\frac(η-η_1)(1-z_m)(η_2-η_1)·z_m=\frack_2a_2k_1a_1=K(a constant)

where a is the degree of association, k the molecular field constant and zm the formal mol fraction of component 2. However, if there occurs a maximum in (η–zm) diagram, we can not evaluate K from the formula, since negative values result in the neighborhood of the maximum. In this case the formula K=η1M2a2⁄η2M1a1 may be preferable provided that the equality K=k2⁄k1=η1M2⁄η2M1 holds for gaseous mixtures where a1=a2=1. The applicability of the formulas is discussed.
Esterification of Alcohols with 1-Acylimidazole Assisted by N-Bromosuccinimide
Authors: Katsuki Tsutomu
Published: July 2006

Treatment of 1-acylimidazoles with alcohols in the presence of N-bromosuccinimide led to the rapid formation of the corresponding esters. The carboxylic acids with less than two hydrogen atoms at their α-positions generally gave good results. Even such a hindered ester as t-butyl pivalate could be prepared by this procedure.
The Nucleophilic Substitution of Dicarboxylic Imides on the Chelate Ring of Tris(3-bromo-2,4-pentanedionato)iron(III)
Authors: Yamamoto Yasuo , Kasuga Kuninobu , Sumita Akira
Published: July 2006

Succinimide and phthalimide were found to be capable of acting as a nucleophilic substituent on the chelate ring of tris(3-bromo-2,4-pentanedionato)iron(III) complex. No analogous reaction has been found between this complex and the other dicarboxylic imides, nor between other metal complexes and dicarboxylic imides including these two imides.
Reaction of Triethylphosphine with Dimethyl Acetylenedicarboxylate in the Presence of p-Chlorobenzaldehyde
Authors: Akiba Kin-ya , Yoneyama Toshio , Inamoto Naoki
Published: July 2006

Reaction of triethylphosphine (1) with dimethyl acetylenedicarboxylate (2) in the presence of p-chlorobenzaldehyde gave dimethyl α-(p-chlorobenzoyl)fumarate (5) and a bicyclic lactone (6). In the presence of water, reaction of 1 with 2 afforded dimethyl fumarate and triethylphosphine oxide.
Effect of Water on the Conductance of Hydrogen Halides in Diethylene Glycol
Authors: Srinivas Rao V , Kalidas C
Published: July 2006

The effect of addition of small amounts of water on the conductance of hydrogen chloride and hydrogen bromide in diethylene glycol at 25 °C was investigated. The Λ0 of both acids sharply decreases with the addition of water, passes through a minimum at about 1.23 wt% of water and then increases. This was explained on the basis of the changes in the proton jump mechanism due to shift of the proton transfer equilibrium, ROH2++H2O\ightleftarrowsROH+H3O+. The role of water in this equilibrium was shown to be similar to the protonation of a Hammett indicator base in acid solutions.
Ion Cyclotron Resonance Study of Ion-molecule Reactions in Benzene: Mechanism of C3H3+ Formation
Authors: Aoyagi Katsuyuki , Hasuda Yoshinori , Irie Masahiro , Hayashi Koichiro , Sohma Junkichi
Published: July 2006

Ion-molecule reactions in gaseous benzene, benzene-d6, and their mixtures, particularly the formation process of C3H3+, have been investigated using ion cyclotron single- and double-resonance techniques. Double-resonance experiments demonstrated that C3H3+ is formed by the ion-molecule reaction: C6H7++C6H6→C3H3++neutral product. In C6H6–C6D6 mixtures, not only C3H3+ but also deuterium substituted ions, such as C3H2D+ and C3HD2+, are formed from C6H7+. Quantitative analysis of the double-resonance intensity revealed that C3H3+ is formed by the decomposition of the intermediate complex of [C6H7+–C6D6], which is a σ-type complex.
CNDO/2 Calculations of Ionization Potentials of Some Fluorosubstituted Conjugated Hydrocarbons
Authors: Hayashi Toshio , Nakajima Takeshi
Published: July 2006

The ionization potentials of the fluorosubstituted derivatives of ethylene, trans-1,3-butadiene, and benzene were calculated by using the modified CNDO/2 method. In agreement with the available experimental facts, the ionization potentials due to the π-electron were predicted to change little on fluorination, while those due to the σ-electron were predicted to suffer a more or less large change on fluorination. An explanation for this fact, called the perfluoro effect, can be given by a simple perturbational treatment.
MO-theoretische Untersuchung der Nucleophilen Substitution Einiger Silacycloalkane
Authors: Frenking Gernot , Kato Hiroshi , Fukui Kenichi
Published: July 2006

CNDO/2 calculations have been carried out for (CH2)n−1SiMeH and (CH2)n−1CMeH with n=3, 4, 5, and 6. It is found that the electronic structure of the two classes of compounds shows principal differences in the ringsize dependence. It is suggested that this is the reason for the different ring dependence of the reactivity in the nucleophilic substitution reaction.
The Synergistic Extraction of Cobalt Ion Fixed on the Ion Exchange Resin with a Mixture of 2-Thenoyltrifluoroacetone and Pyridine Bases
Authors: Tamura Tooru , Ohzeki Kunio , Kambara Tomihito
Published: July 2006

The extraction of cobalt(II) on the ion exchange resin into a mixture of 2-thenoyltrifluoroacetone(Htta) with pyridine bases in various organic solvents has been studied. In the presence of pyridine bases(B), cobalt ions were extracted from the resin into the organic phase in the form of base adducts, Co(tta)2Bn. The synergistic effect decreased in the order: pyridine>β-picoline>γ-picoline>α-picoline>γ-collidine\simeqisoquinoline\simeqpiperidine>4-benzoylpyridine. This trend was related to its structure, particularly the steric effect of the ortho-substituent.
Impurity Metal-Activated Crystal Growth of Niobium Monophosphide from Gas Phase
Authors: Motojima Seiji , Izushi Toyohiko , Sugiyama Kohzo , Takahashi Yasutaka
Published: July 2006

Niobium monophosphide single crystals were obtained by chemical vapor deposition from a gas mixture of NbCl5, PCl3, H2, and Ar on a quartz substrate using metallic impurity. The existence of Au, Pt, Pd, and Ni resulted in the growth of whiskers or pillar crystals. Maximum whisker length of 5 mm and thickness of 30 μm were obtained at 1150 °C for an hour with the use of Pt impurity. Platelet crystals (400×1000×20 μm, max.) were obtained with the use of Pt at 1240 °C. The growth directions of the whiskers and some platelet crystals were assigned to 〈001〉 and a direction in (001) plane, respectively. The optimum growth conditions for the pillar crystals in the case of Ni impurity: substrate temperature 1000–1020 °C, gas flow ratio PCl3/(NbCl5+PCl3) of 0.7–0.75. From observation of the tip and base of pillar crystals grown with Ni, the growth mechanism seems to be base VLS followed by VS.
The Extraction Spectrophotometric Determination of Palladium with Monothiodibenzoylmethane
Authors: Prabhu B N , Khopkar S M
Published: July 2006

Monothiodibenzoylmethane (HSDBM) was used for the quantitative extraction of palladium. It was extracted at pH 3.5–6.5, with 0.001 M HSDBM in benzene, as an orange-red colored complex and measured spectrophotometrically at 470 nm. Beer’s law was valid in the concentration range of 0.6 to 3.6 μg of palladium per ml. The complex was stable for at least 144 h. Ten milliliters of 0.001 M HSDBM in benzene was adequate for quantitative extraction of palladium. The optimum period of equilibration was 10 min. It was possible to extract palladium in the presence of a large number of elements.