bluuebunny/crossref_metadata_2025 huggingface dataset:
The Crystal Structure of Hemimellitic Acid Dihydrate
Authors: Takusagawa Fusao , Shimada Akira
Published: July 2006

The crystal structure of hemimellitic acid dihydrate (benzene-1,2,3-tricarboxylic acid dihydrate) has been determined by the X-ray diffraction method. The crystals are triclinic, with a space group of P\bar1 and with cell dimensions of a=11.02, b=9.12, c=8.72 Å, α=106.2°, β=140.2°, and γ=84.2°. The structure was determined by an inspection of a sharpened Patterson map. The final R value was 9.25% for 1532 observed reflections. The hemimellitic acid molecule has the approximate Cs symmetry. Three carboxyl groups twist by 4.5°, 86.8°, and 10.3° out of the plane of a benzene ring. The hemimellitic acid and water molecules are joined by seven independent O–H···O hydrogen bonds to form a three-dimensional network. The water molecules are hydrogen-bonded to each other around a center of symmetry to form a unique four-membered ring. The hydrogen bonds observed are classified by means of the combination of donor and acceptor groups in five types. These types of hydrogen bonds are discussed in the comparison with several carboxylic acid hydrates.
The Ultrasonic Velocity and the Absorption of Aqueous t-Butyl Alcohol Solutions in Relation to the Structures of Water and Solutions
Authors: Endo Harumi , Nomoto Otohiko
Published: July 2006

The adiabatic compressibility vs. concentration curves in aqueous solutions of t-butyl alcohol (t-Bu) over a certain temperature range have a common intersection at a fixed concentration (μcβ). The sound absorptions of solutions are nearly constant and are independent of the concentration up to a concentration (μiα) nearly the same as the μcβ. On the basis of the value of μcβ(≅μiα), the properties and the dissolved state of t-Bu in liquid water discussed in terms of the liquid clathrate hydrate model. At this concentration, the liquid clathrate hydrate of t-Bu. consists of 18-hedron, containing 32 water molecules for each t-Bu molecule. For higher concentrations than μcβ, the breakdown of the liquid clathrate hydrate by the addition of excess t-Bu occurs, accompanied by an increase in the number of clusters.
ESR Evidence for the Destruction of the Four-membered Chelate Structure of Bis(O,O′-diethyldithiophosphato)oxovanadium(IV) by Pyridine Bases
Authors: Sato Mitsuo , Fujita Yuzaburo , Kwan Takao
Published: July 2006

The interaction of bis(O,O′-diethyldithiophosphato)oxovanadium(IV), VOdtp2, with pyridine bases has been studied in toluene by ESR. It has been found that the four-membered chelate structure of VOdtp2 is disrupted by pyridine bases to form the complex species identified as VOdtp2·Py and VOdtp2·Py2 by their characteristic ESR spectra. The coordination structures of the newly-formed complexes are discussed in association with the substitution equilibria involved.
Photolysis of Ethylene at 1634 Å and 1849 Å
Authors: Hara Hiroshi , Tanaka Ikuzo
Published: July 2006

The photolysis of ethylene was carried out at room temperature at 1634 Å and 1849 Å. Products at both wavelengths were hydrogen, acetylene, ethane, n-butane and 1-butene. Product analysis and the radical scavenger technique indicate the primary processes to be as follows.

(Remark: Graphics omitted.)

The molecular elimination process in the primary processes varied with wavelengths, and was determined to be 47% and 53% at 1634 Å and 1849 Å, respectively. With reference to the percentage reported at other wavelengths, it is pointed out that molecular elimination is suppressed with the increase in excitation energy.
Molecular Interactions of p-(N,N-Dimethylamino)-Benzonitrile. Electrostatic Self-Complex and Hetero-Complex Formation in the Ground and Excited States
Authors: Narashima Nobuaki , Mataga Noboru
Published: July 2006

Electrostatic self-complex formation of p-(N,N-dimethylamino)-benzonitrile and its hetero-complex formation with benzonitrile in cyclohexane matrix were studied in detail. The possibilities of ground state complex and excimer formation in various liquid solvents were examined thoroughly.
Brillouin Scattering and Elastic Constants of Potassium Bromide
Authors: Matsuura Hiroatsu , Miyazawa Tatsuo
Published: July 2006

The Brillouin scattering of KBr crystals was measured by using a helium–neon laser and a pressure-scanned Fabry-Perot interferometer. The Brillouin shifts were measured for various crystal orientations with the scattering vector in the [110] plane. In addition to the strong Brillouin peaks due to the longitudinal acoustic mode, relatively weak Brillouin peaks due to the transverse mode with admixture of the longitudinal mode were clearly resolved for a certain range of crystal orientations. From these Brillouin shifts, the frequencies and velocities of thermally excited sound waves of the wavelength 286.9 nm were obtained, and the three independent elastic constants of the KBr crystal for sound waves of microwave frequencies 6–12 GHz were determined as C11=3.37×1011, C12=0.61×1011 and C44=0.51×1011 dyn/cm2. The elastic constants determined in the present study were close to the ultrasonic values, indicating little dispersion of the sound velocities for the regions between 10 MHz and 10 GHz.
Molecular Structure of Acetamide as Studied by Gas Electron Diffraction
Authors: Kitano Mitsuo , Kuchitsu Kozo
Published: July 2006

The bond distances (rg) and angles (rα) in acetamide CH3CONH2 have been determined by gas electron diffraction as follows: C–C=1.519±0.006 Å, C–N=1.380±0.004 Å, C=O=1.220±0.003 Å, C–H (average)=1.124±0.010 Å, N–H (average)=1.022±0.011 Å, ∠N–C=O=122.0±0.6°, ∠C–C–H (average)=109.8±2°, and ∠C–C–N=115.1±1.6° (or 112.2±1.6°). In comparison with the molecular structure in the crystal, the C–N bond is about 0.05 Å longer, whereas the C=O bond is about 0.04 Å shorter. The C–N and C=O bonds appear to be slightly shorter than the corresponding bonds in N-methylacetamide.
Derivatographic Studies on Transition Metal Complexes. XI. Thermal Ligand-exchange Reaction of cis- and trans-[CoXY(N4)]SCN·nH2O Type Complexes
Authors: Tsuchiya Ryokichi , Murakami Tatsuo , Kyuno Eishin
Published: July 2006

The thermal ligand-exchange reaction was investigated by derivatographic and isothermal methods for the following complex thiocyanates: cis-[CoCl2en2]SCN, cis-[CoClBren2]SCN·H2O, cis-[CoBr2en2]SCN·H2O and the corresponding trans-complexes, and several corresponding triethylenetetramine complexes cis-α-[CoXYtrien]SCN·H2O, where X and Y represent Cl− and Br− ion, respectively. cis-Complexes, except for cis-[CoCl2en2]SCN were found to exhibit obviously the ligand-exchange reaction in which Cl− or Br− is substituted by SCN− just after the liberation of lattice water takes place. On the other hand, cis-[CoCl2en2]SCN showed only partial ligand-exchange reaction accompanied by immediate thermal decomposition even at higher temperature than in the other monohydrates. In contrast, all the anhydrated trans-complexes trans-[CoCl2en2]SCN, trans-[CoClBren2]SGN and trans-[CoBr2en2]SCN did not give such a reaction upon heating. The activation energies of cis-[CoClBren2]SCN·H2O were found to be Ea=26±2 kcal/mol for dehydration and Ea=54±2 kcal/mol for ligand-exchange. The thermal ligand-exchange reaction proceeded in cis-type complexes without change in the geometrical configuration of the original complexes. No racemization or inversion could be observed in the optically active complex.
Reaction of 3,4,5,6-Tetrahydro-2H-azepin-7-ol Hydrogen Sulfate with Nucleophilic Reagents
Authors: Masaki Mitsuo , Uchida Masaru , Fukui Kiyoshi
Published: July 2006

The reaction of 3,4,5,6-tetrahydro-2H-azepin-7-ol hydrogen sulfate with nucleophilic reagents was studied. The tetrahydroazepin-7-ol hydrogen sulfate reacted with alcohols and oximes to give respectively ε-caprolactam and the corresponding hydrogen sulfate of the reagents in good yields. Treatment with cyclohexylamine or benzylamine afforded ε-caprolactam, the amine salt of the corresponding sulfamic acid, and the corresponding amine salt of the tetrahydroazepin-7-ol hydrogen sulfate, while anilinium phenylsulfamate was formed exclusively in the reaction with aniline. From these results, the tetrahydroazepin-7-ol hydrogen sulfate was confirmed to undergo exclusively a cleavage of the oxygen-sulfur bond by an attack of nucleophiles on the sulfur atom.
Telomerization of Ethylene with Carbon Tetrachloride Initiated by N-Chloroalkylamines
Authors: Asahara Teruzo , Sen\={o} Manabu , Ohtani Noritaka
Published: July 2006

By using various N-chloroalkylamines, the telomerization of ethylene with carbon tetrachloride was carried out in a stainless steel autoclave at 130 °C. It was found that the yields and the compositions of telomers varied widely according to the kinds and the structures of N-chloroalkylamines. When N-chloromonoalkylamines or N-chlorodialkylamines were used, the total yield of telomers was high compared with the case using N,N-dichloroalkylamines. In the presence of both N-chloromonoalkylamines and N-chlorodialky]amines, the total yield of telomers became higher and the greater part of the telomers was 1:1 adduct (n=1 telomer CCl3CH2CH2Cl) of ethylene with carbon tetrachloride.
Photoinduced Reactions. LXXIII. Solvent Dependence in the Photochemical Reaction of α-Nitroepoxides
Authors: Saito Isao , Takami Masaaki , Konoike Toshiro , Matsuura Teruo
Published: July 2006

The photochemical reaction of α-nitroepoxides showed marked solvent dependence. The photolysis of (1,2-epoxy-2-nitropropyl)benzene (I) in 2-propanol led to the formation of three products 1-phenyl-1-isopropoxy-2-propanone (IIb), 1-phenyl-1,2-propanedione oxime (III) and 1-hydroxy-1-phenyl-2-propanone oxime (IV), whereas on irradiation in ether I gave exclusively IV. However, in t-butyl alcohol, benzene, acetone, acetonitrile or n-hexane, I was not susceptible to photolysis. The photolysis of α,α′-epoxy-α-nitrobibenzyl (V) in ether gave benzoin oxime (VII) in addition to benzaldehyde and benzoic acid, whereas in methanol it gave benzoin methyl ether (VI) in the dark. These reactions are interpreted in terms of effects of the acidity and hydrogen-donating property of solvents on the excited α-nitroepoxides. The pyrolysis of I and V were also examined.
Branched-chain Sugars. IV. Synthesis of 5,6-Dideoxy-5-C-hydroxymethyl-1,2-O-isopropylidene-6-C-nitro-3-O-substituted-α-d-glucose Derivatives
Authors: Yoshimura Juji , Iida Takao , Wakai Hiroo , Funabashi Masuo
Published: July 2006

Addition of nitryl iodide to 5-deoxy-1,2,O-isopropylidene-3-O-methyl-5-C-methylene-6-O-substituted-α-d-xylo-hexofuranoses (3 and 4), and subsequent hydrogenation with sodium borohydride gave a mixture of the corresponding 5,6-dideoxy-5-C-hydroxymethyl-6-C-nitro derivatives of d-gluco and l-ido forms. The configuration of both isomers were determined by intramolecular cyclization into the corresponding nitrocyclohexanetetrols. The ratios of d-gluco to l-ido product were 1: 2 in the case of 6-O-trityl derivative (3) and 4: 5 in the case of 6-O-benzyl derivative (4), respectively.
Solid Phase Peptide Synthesis by Oxidation-Reduction Condensation. Synthesis of LH–RH by Fragment Condensation on Solid Support
Authors: Matsueda Rei , Maruyama Hiroshi , Kitazawa Eiichi , Takahagi Hidekuni , Mukaiyama Teruaki
Published: July 2006

Solid phase peptide synthesis by oxidation-reduction condensation was investigated. The fragment condensation on solid support was examined by employing two types of chain elongation, that from C-terminal amino acid to N-terminal amino acid (A type elongation) and that from N-terminal amino acid to C-terminal amino acid (B type elongation). The feasibility of these two approaches A and B was demonstrated in two syntheses of LH–RH (luteinizing hormone-releasing hormone). The LH–RH prepared from the two different chain elongations showed identical mobilities on tlc, exhibiting full activities of natural LH–RH (AVS 77-33 # 215-269).
The Reactions of the Hexafluorothioacetone Dimer with Nucleophiles in the Presence of the Fluoride Ion
Authors: Kitazume Tomoya , Ishikawa Nobuo
Published: July 2006

In the KF–DMF system, the hexafluorothioacetone dimer (1) reacted with alcohols, alkanethiols, and thiophenols under mild conditions. The products, 2, 3, 10, and 12, were assumed to have resulted from the hexafluorothioacetone monomer (4) and the nucleophiles. Cycloadducts of 4 and anthracene or styrene were also obtained readily from the dimer (1) and the dienes.
Impurity Effect on Domain Formation in a Nematic Liquid Crystal
Authors: Nakauchi Jun , Yokoyama Masaaki , Sawa Hiroshi , Okamoto Ken-ichi , Mikawa Hiroshi , Kusabayashi Shigekazu
Published: July 2006

The effect of impurity on domain formation in an ethyl anisal-p-aminocinnamate nematic liquid crystal was investigated. With the decrease of the content of ionic impurities, the threshold voltage of the domain formation increases and the size of the domain patterns becomes larger. With blocking electrodes, the domain patterns could not be seen, although molecular orientation was still observed. When a negative electrode is coated partly with Nesa and partly with gold, the domain patterns appear first in the Nesa (n-type) part. When an electric field is cut and applied within one second intervals, the domains reappear at the same places. The mechanism of domain formation is discussed.
The Self-diffusion of Chloride Ions in Divalent Metal Chloride Crystallites with CdCl2-type Structure
Authors: Sensui Yoshihiro
Published: July 2006

The self-diffusion of chloride ions in MgCl2- and CoCl2-crystallites with the CdCl2-type structure was studied, the results being compared with previous data on MnCl2 and NiCl2. The diffusion rate was measured through gas/solid-isotopic exchange reactions in a carefully cleaned vacuum system. The results were analyzed by the use of a model of semi-infinite crystal. The Arrhenius plots of apparent diffusion coefficient consist of two segments of line, from whose slopes the activation heat of migration E and the apparent heat of formation of vacancies Hv⁄nv are determined. [Hv denotes the total heat of formation of two anion vacancies and one catoin vacancy with nv=2 or 3.] The values for E and Hv were 0.55 and 1.1 eV in MgCl2 and 1.3 and 2.0 eV in CoCl2, respectively. A linear relationship holds between the logarithms of pre-exponential factor of the diffusion coefficient and E or (E+Hv⁄nv); viz., the theta-rule holds in this case. In the initial stage of the exchange reaction, ions or atoms in the surface region of crystals were observed to easily migrate. Sodium ions doped deliberately as impurity enhance the diffusion of chloride ions. It is concluded that the diffusion takes place through the vacancy mechanism.
Hydrogen Formation in the Gas-Phase Radiolysis of C2H4–D2O Mixtures
Authors: Kuwabara Ken-ichi , Hatano Yoshihiko
Published: July 2006

The total hydrogen yields and their isotopic compositions have been measured in the gas-phase radiolysis of C2H4–D2O mixtures at room temperature. A mixture of D2O (<10 mol %) with a large amount of C2H4 was used to avoid the effect of the wall on the decomposition of D2O. The contribution of thermal hydrogen atoms to the hydrogen formation may reasonably be excluded in this system. The kinetic treatment of D2 and HD formation suggests the decomposition mechanism of D2O. No important contribution of hot hydrogen atoms was observed. The yield of hydrogen from the D2O formed by the unimolecular process, G1D=0.4, was nearly equal to the molecular hydrogen yield reported previously.
Kinetics of the Hydrolysis of Diethyl Acetal Catalyzed by Iron(III) in Aqueous Solution
Authors: Wada Goro , Sakamoto Machiko
Published: July 2006

The catalytic activity of iron(III) on the hydrolysis of diethyl acetal was investigated in aqueous solutions. The reaction rate was followed dilatometrically. The reaction is of the first order with respect to acetal concentration, the rate constant being expressed by

K_app=k_o+k_H[H^+]+k_Fe[Fe].

The respective rate constants are k0=1.30×10−4 s−1, kH=1.28 M−1 s−1, and kFe=1.86 M−1 s−1 at an ionic strengt μ=0.2 M and 25 °C. A tentative reaction scheme for iron(III) catalysis was proposed.
Vibration-Rotation Spectrum of Methyl Fluoride. I. Analysis of 2ν3 Band
Authors: Nakagawa Jun , Suzuki Isao , Shimanouchi Takehiko , Fujiyama Tsunetake
Published: July 2006

The 2ν3 band of methyl fluoride has been measured with a high-resolution infrared spectrometer. The following molecular constants are obtained: ν0=2081.382, B″=0.85172, B′=0.82955, (A″–A′)=0.01953, DJ″=1.95×10−6, DJ′=1.78×10−6, DJK″=1.47×10−5 (assumed), DJK′=1.93×10−5, and (DK″–DK′)=5.9×10−6cm−1. In addition, the hot band (3ν←ν3) and the isotope 13CH3F band have been observed and analyzed. The cubic force constant k333 was also obtained from the vibration-rotation constants.
Polarographic Studies of the Rates of the Dissociation Reactions of Cobalt(II)-Iminodiacetate, -Aspartate, and -2,2′-Ethylenedioxydi(ethylamine)-N,N,N′,N′-tetraacetate Complexes
Authors: Kodama Mutsuo
Published: July 2006

The cobalt(II)-IDA, -Asp, and -GEDTA complexes produce kinetic wave due to their dissociation preceding the electron-transfer step at the electrode surface. From an experimental examination of the nature of these kinetic waves, the dissociation mechanisms were determined to be:

i) IDA and Asp systems,

CoX22−\ightleftarrowsCoX0+X2− rate-determining step

CoX0+2e−+Hg\ightleftarrowsCo(Hg)+X2−

ii) GEDTA system,

CoY26−\ightleftarrowsCoY2−+Y4− in a rapid equilibrium

CoY2−\ightleftarrowsCoY2−* rate-determining step

CoY2−*+2e−+Hg\ightleftarrowsCo(Hg)+Y4−

where CoY2−* is the electroactive cobalt(II)-GEDTA complex produced upon the partial dissociation of the normal cobalt(II)-GEDTA complex with a 1 : 1 composition. From the relative rate constants for these complexes, the detailed structures of the reaction intermediates in their dissociation were also obtained.
Spectra of Nickel(II)-Azide Complexes in Organic Solvents
Authors: Abu-Eittah R , Elmakabaty S
Published: July 2006

The complexing properties of nickel(II) ion with azide ion, in a number of organic solvents, are investigated by spectroscopic methods. The electronic absorption spectra of Ni(II)–N3− solutions were studied in the visible-ultraviolet regions using dimethylformamide, absolute methanol and absolute ethanol as solvents. The composition of the possibly obtained complexes was investigated using the continuous variation and the slope ratio methods. The composition of the predominant complex was dependent on the solvent used. Formation as well as dissociation constants of the obtained complexes were computed.
Kinetics of the Formation of MoO3−x at Elevated Temperatures from a Mixture of MoO3 and α-Al2O3
Authors: Kotera Yoshihide , Ueno Akifumi
Published: July 2006

The kinetics of the formation of MoO3−x from a mixture of MoO3 and α-Al2O3 was studied by means of high temperature X-ray diffraction. The species of MoO3−x formed in the temperature range 600–700 °C were identified as MoO2.88(Mo8O23),(MoO2.76(MoO17O47), and MoO2.75(Mo4O11). The activation energies of their formation were estimated to be 18.4 kcal/mol for Mo8O23, 23.0 kcal/mol for Mo17O47 and 29.2 kcal/mol for Mo4O11. Other types of species of MoO3−x observed above 800 °C were MoO2.89(Mo9O26) and MoO2. Little effect of water vapor, oxygen or nitrogen on the formation of the species was observed. No MoO3−x. was observed in the mixture of MoO3, with SiO2 or α-Fe2O3.
The Fluorination of Carbonyl Sulfide
Authors: Nagase Shunji , Baba Hajime , Kodaira Kazuo , Abe Takashi
Published: July 2006

The electrochemical fluorination of carbonyl sulfide has been carried out. Garbonyl fluoride and sulfur hexafluoride were obtained as the principal products. The influence of the operating conditions on the reaction has been examined. In addition, a method has been developed for the production of sulfur hexafluoride. This involves the passage of carbon monoxide and sulfur over a catalyst; the resultant gas formed is subsequently introduced into a current-carrying anhydrous hydrogen fluoride in an electrolytic cell. Sulfur hexafluoride was thus obtained in a good yield.
Trimethylenediamine Complexes. III. cis-trans Isomeric Pairs of Diazido- and Dicyano-bis(trimethylenediamine)cobalt(III) Complexes
Authors: Kawaguchi Hiroshi , Kawaguchi Shinichi
Published: July 2006

trans-Diazido- and dicyano-bis(trimethylenediamine)cobalt(III) complexes have been prepared by the ligand substitution reactions of trans-dichlorohis(trimethylenediamine)cobalt(III) complexes in methanol. The corresponding cis isomers were obtained by similar reactions in aqueous solutions. The structural assignment of these isomeric pairs was made on the basis of electronic, infrared and nuclear magnetic resonance spectra.
A New Catalyst for Ethylene Polymerization Containing Nickel Oxide
Authors: Maruya Ken-ichi , Ozaki Atsumu
Published: July 2006

A new catalyst for ethylene polymerization NiO–NiSO4, was found from a study of NiO–SiO2, and NiCl2 catalysts. The Ni–NiSO4 catalyst prepared from mixtures of formate and sulfate is much less active than NiO–NiSO4 prepared from mixtures of hydroxide and sulfate. Poisoning behavior of carbon monoxide and water is quite similar to NiO–SiO2 catalyst. An equimolar mixture of NiO–NiSO4 gives maximum activity. The active species is postulated to be hydroxy sulfate of nickel. The structure of the active site is discussed.
(1,3-Dithiolan-2-yl)trimethylammonium Iodide. An Electrophilic Dithiolanylating Reagent
Authors: Hiratani Kazuhisa , Nakai Takeshi , Okawara Makoto
Published: July 2006

The reactions of (1,3-dithiolan-2-yl)trimethylammonium iodide (5), readily obtained by methylation of 2-dimethylamino-1,3-dithiolane (2), with aromatic amines were studied. It was found that 5 served as an electrophilic 1,3-dithiolanylating reagent; the reactions with aniline, N-methylaniline, and benzylamine gave N-dithiolanylated products while those with N,N-dimethylaniline and indole yielded exclusively C-dithiolanylated products via aromatic substitutions. Furthermore, C-dithiolanylated compounds were hydrolyzed to aldehydes using HgO–BF3·OEt2. The present aldehyde synthesis has been compared with an alternative electrophilic formylation method the Vilsmeier reaction.
Reduction of gem-Bromofluorocyclopropanes with Organosilicon Hydrides
Authors: Ando Teiichi , Hosaka Hirokazu , Funasaka Wataru , Yamanaka Hiroki
Published: July 2006

7-Bromo-7-fluoronorcarane, 1-bromo-1-fluoro-2-phenylcyclopropane, and 7-bromo-7-fluoro-2-oxanorcarane were reduced with tri-n-butylsilane or di-n-butylsilane at 100–145 °C in the presence of a small amount of radical initiator, to afford the corresponding monofluorocyclopropanes. It has been found, by examining the stereochemistry of the reduction, that the extent of stereospecificity is dependent on the reaction temperature as well as on the kind of the silicon hydride used. Comparison of these results with those of the tri-n-butyltin hydride reduction shows that the reactivity of metal hydrides as a reducing agent of gem-dihalocyclopropanes is in the order Bu3SnH>Bu2SiH2>Bu3SiH. These observations are well explained by postulating that the α-fluorocyclopropyl radical has a pyramidal configuration and that the extent of stereospecificity is determined by the relative rates of its inversion of configuration and its hydrogen abstraction from the tin or silicon hydride. The reduction of 7,7-dibromonoracrane with tri-n-butylsilane or di-n-butylsilane gave a mixture of the two geometrical isomers of 7-bromonoracrane, whose composition (endo-Br/exo-Br\fallingdotseq3.0) was nearly identical irrespective of the reaction temperature and of the reactivity of silicon hydride.
Cycloaddition Reaction of Cycloheptatriene and Nitrosobenzene Derivatives
Authors: Itô Shô , Narita Sen-ichi , Endo Katsuya
Published: July 2006

Structures of the cycloaddition products obtained from cycloheptatriene and para-substituted nitrosobenzene have rigorously been established by NMDR experiments and by degradation of the representative member, the cycloheptatriene-nitrosobenzene adduct, to 3-anilinocycloheptanone. All the adducts were found to be of [6+2] type. The ionic mechanism has been proposed for the cycloaddition in order to account for the substitution effect on the benzene ring.
The Synthesis of 3-Methyl-5-(2-aminoalkyl)isoxazoles
Authors: Kashima Choji , Tsuda Yoshihiko
Published: July 2006

The reaction of 3,5-dimethylisoxazole with Scruff bases gave 3-methyl-5-(2-aminoalkyl)isoxazole derivatives in the presence of sodium amide in liquid ammonia. The N-alkylation on the anilino group of 3-methyl-5-(2-anilino-2-phenylethyl)isoxazole resulted in deamination, thus giving 3-methyl-5-styrylisoxazole. The reaction of 3,5-dimethylisoxazole with benzonitrile gave 3-methyl-5-(2-aminostyryl)isoxazole, which was then reduced to 3-methyl-5-(2-amino-2-phenylethyl)isoxazole.
Generalized Method for Calculating Löwdin Orbitals
Authors: Suzuki Kazuya , Maruyama Shinsaku , Araki Kunio
Published: July 2006

A generalized method for numerically calculating Löwdin orbitals is proposed, the method being an application of Frobenius’ theorem in algebra. Löwdin transformation matrix T=S−1⁄2 (S is overlap matrix) is calculated as T=US0−1⁄2  Ut, where S0 is a diagonal matrix whose diagonal elements are eigen values of S, U is a matrix whose column vectors are eigen vectors of S and Ut is the transposed matrix of U. It is proved that the eigen values of the overlap matrix of S are always positive for any choice of linearly independent atomic orbitals and that S−1⁄2, the inverse square-root of S, exists within the range of real numbers. This method is useful for computer calculation by applying Jacobi’s method.
The Selective Hydrogenation of α-Methylcinnamaldehydes Catalyzed by Cobalt Carbonyl in the Presence of Amines
Authors: Kogami Kunio , Kumanotani Ju
Published: July 2006

The selective hydrogenation of α-methylcinnamaldehydes to the hydrocinnamaldehydes, catalyzed by cobalt carbonyl and a limited amount of amines, has been investigated. The addition of such amines as diisopropylamine, diethanolamine, tributylamine, triethylamine, and pyridine showed a remarkable selectivity and gave the desired α-methylhydrocinnamaldehydes in 96.4–91.5% theoretical yields. Especially, diisopropylamine gave the best selectivity, in it the yields of p-t-butyl-α-methylhydrocinnamaldehyde and cyclamenaldehyde amounted to 96%. The optimum amount was found to be 1.0–1.3 equivalents of cobalt carbonyl.
Group Interactions in Polyelectrolytes. VII. Amination Kinetics of Chloromethylated Polystyrene with Butylamine Isomers
Authors: Kawabe Hiroshi , Yanagita Masaya
Published: July 2006

The amination of chloromethylated polystyrene (CMPS) and benzyl chloride with butylamine isomers and diethylamine was investigated kinetically in dioxane, methyl ethyl ketone (MEK), and N,N-dimethylformamide (DMF). Although the amination of i- and s-butylamine conformed to the ordinary second-order kinetics in all the solvents, deceleration was observed during the course of the amination of CMPS with n-butylamine in MEK as well as in dioxane, with t-butylamine in DMF, and with diethylamine in both dioxane and DMF. The intrinsic rate constants of the amination of CMPS were generally almost the same as those of benzyl chloride. The magnitudes of the rate constants in each solvent were in this order; n-butyl>i-butyl>s-butyl>t-butyl; it was in the order of DMF>>MEK≈dioxane with all the amines investigated. These results were interpreted in terms of both the structures of the amines and the interaction between the amine and the solvent molecules.
An Investigation of the Gas-Solid Interface Reaction
Authors: Katsumoto Masayuki , Fueki Kazuo , Mukaibo Takashi
Published: July 2006

The isotopic exchange between H2S and D2 on molybdenum disulfide and manganese sulfide has been studied kinetically between 420° and 500 °C. The reaction proceeded via these steps:

& H_2S+D_2=D_2S+H_2

& H_2+D_2=2HD

From the analysis of the kinetic data, the rate constant of the sulfurization of both metal sulfides by “hydrogen sulfide,” ki, and that of their reduction by “hydrogen,” ki′, were calculated. The dependence of these rate constants on the sulfur activity was determined. A possible mechanism of the reaction at the surface of the sulfides is discussed in this paper.
Raman Spectra and Internal Rotation of Ethyl Methyl Ether
Authors: Kitagawa Teizo , Kusaki Kazuo , Miyazawa Tatsuo
Published: July 2006

The Raman spectra of ethyl methyl ether in the liquid state were measured at various temperatures from 298 K to 195 K. The energy difference between the gauche and trans isomers in the liquid state was found to be 1.1 kcal/mol. This value is appreciably higher than the value 0.77 kcal/mol for n-butane. The tendency of assuming the trans form is higher for the CH2–O bond than for the CH2–CH2 bond. The infrared intensity of the band at 465 cm−1 (gas) is largely due to the gauche isomer but the Raman intensity of the line at 471 cm−1 (liquid) is largely due to the trans isomer.
On the Decomposition of C6H5CO+ Ions Produced from Several Alkyl Phenyl Ketones by Electron Impact
Authors: Tajima Susumu , Wasada Nobuhide , Tsuchiya Toshikazu
Published: July 2006

The decomposition of C6H5CO+ ions produced by electron impact from seven alkyl phenyl ketones, C6H5COR (R=H, CH3, C2H5, n-C3H7, iso-C3H7, n-C4H9, n-C5H11), has been studied. By determining the heats of formation, the C6H5CO+ ions produced from the different precursors in the vicinity of the threshold are shown to have the same structure, and it is also shown that there is a linear relationship between the heat of formation of the activated complex for the reaction C6H5CO+→C6H5++CO and the vibrational degrees of freedom of the neutral fragment, R.
Effects of Inorganic Salts on the Dissociation of a Complex of β-Cyclodextrin with an Azo Dye in an Aqueous Solution
Authors: Mochida Kazuo , Kagita Akio , Matsui Yoshihisa , Date Yoshio
Published: July 2006

The apparent dissociation constant (Kapp) of a complex between β-cyclodextrin and an azo dye, sodium p-(4-hydroxy-1-naphthylazo)benzenesulfonate, was determined by spectrophotometry in a phosphate buffer solution (pH 5.91) in the absence and in the presence of various inorganic salts at 25 °C. The cyclodextrin and the azo dye formed a 1 : 1 complex with the Kapp value of 2.44×10−3 M in a 0.1 M phosphate buffer. Kapp decreased with an increase in the concentration of the phosphate buffer and with the addition of some inorganic salts, such as Li2SO4, Na2SO4, K2SO4, LiIO3, NaIO3, KIO3, and KF. These results were explained mainly in terms of the decrease in the activity of water, which takes part in the dissociation reaction of the inclusion complex, with an increase in the concentration of the inorganic salts. On the other hand, Kapp increased with the addition of such salts as KCl, KBr, KI, KNO3, KSCN, and KClO4. These results were attributed mainly to the formation of the inclusion complexes of the cyclodextrin with the anions of these salts, competing with the azo dye for the cyclodextrin-binding site.
Electron-diffraction Investigation of the Molecular Structure of Tetramethyltin
Authors: Nagashima Makoto , Fujii Hideji , Kimura Masao
Published: July 2006

The structure parameters of tetramethyltin have been determined by gas-phase electron diffraction to be as follows: rg(Sn–C)=2.1436±0.0030 Å, rg(Sn···H)=2.7642±0.0125 Å, rg(C–H)=1.1179±0.0090 Å, l(Sn–C)=0.0496±0.0098 Å, and l(Sn···H)=0.1532±0.0132 Å. The experimental molecular intensity has been well reproduced by the molecular model in which the methyl groups are rotating freely, or nearly freely. The scattering factors, based upon the relativistic Hartree-Fock-Slater or the Hartree-Fock atomic potential, have given a theoretical background in better agreement with the experimental one and have led to a more reasonable Sn–C mean amplitude than did the scattering factors based upon the Thomas-Fermi-Dirac or the Thomas-Fermi atomic potential.
Self-diffusion of a Cation through Cation Exchange Membrane and Membrane Permeability
Authors: Kaibara Kozue , Saito Keiji , Kimizuka Hideo
Published: July 2006

The self-diffusion coefficient of an ion and the membrane permeability were studied with a system consisting of two identical electrolyte solutions separated by a cation exchange membrane. The membrane permeability to cation was estimated from the membrane conductance data. The result indicated that the membrane permeability increased with a decrease in electrolyte concentration. The self-diffusion coefficients and the concentrations of Na+, Cs+, and Ca2+ in the membrane were also measured by the radiotracer method. At concentrations less than 0.1 M, the self-diffusion coefficients more or less increased with increasing concentrations, while the concentrations within membrane remained almost constant. The membrane permeability to ion estimated from the conductance data was in excellent agreement with that calculated by the relation in which the membrane permeability is given as the self-diffusion coefficient times the partition coefficient divided by the membrane thickness.
Ionic Equilibria in Mixed Solvents. X. Hydrolysis of Nickel(II) Ion in Dioxane-Water Mixtures
Authors: Kawai Takayoshi , Otsuka Haruko , Ohtaki Hitoshi
Published: July 2006

The hydrolytic reactions of nickel(II) ion were studied at 25 °C in water and dioxane-water mixtures containing 3 M (Li)ClO4 as an ionic medium. Emf measurements were carried out in the range of the total nickel(II) ion concentration of 0.02469–0.7891 M in water, 0.02488–0.7996 M in a 0.1 mole fraction (35.21% w/w) dioxane-water mixture and 0.05170–0.9016 M in a 0.2 mole fraction (55.01% w/w) dioxane-water mixture, respectively. Some supplementary measurements were performed in a 0.5 mole fraction (83.02% w/w) dioxane-water mixture. Only the Ni4(OH)44+ complex was found in all solvent systems and its formation constant in log*β44 was −27.32±0.08 (in water), −27.11±0.08 (in a 0.1 mole fraction dioxane-water mixture), and −27.04±0.05 (in a 0.2 mole fraction dioxane-water mixture). In order to test the relative change of the formation consatnt of the Ni4(OH)44+ complex over the whole solvent composition examined, the variation of the formation constant was measured with the continual change of solvent composition at constant Z. Approximate values of the solubility products of Ni(OH)2 and NiOHClO4 precipitates were estimated from maximum values of Z.
The Separation of Silver, Bismuth, Cadmium, and Zinc as Their Trioctylamine Complexes by Extraction Chromatography
Authors: Honjo Takaharu , Ushijima Shigeru , Kiba Toshiyasu
Published: July 2006

The behavior of milligram amounts of silver, bismuth, cadmium, and zinc in liquid-liquid extraction has been studied with 20% trioctylamine (TOA) in carbon tetrachloride. The results have also been applied to the separation of the four metals as their TOA complexes by extraction chromatography. After passing a sample solution of 2 M HCl through a column (φ1cm×1 30 cm) consisting of a stationary phase of TOA–CCl4 on Kel-F, the metal ions were retained and then eluted with 5.5 M HCl at the rate of 0.5–1 ml/min at 20±1 °C. Silver was found in 90–180 ml of the effluent; Bi was flowed down in 200–500 ml of the same effluent. The cadmium and Zn were held so firmly on the column that they could not be removed under the above conditions. Therefore, water was passed through to release these metals. Zinc was first flowed down with 0–50 ml, and then Cd, with 200–500 ml of water. When 5M HNO3 was used as the eluting solution instead of water, the Cd was immediately removed from the column. The percentage recovery of these metals in the extraction chromatography was estimated as 101% (Ag), 99% (Bi), 97% (Cd), and 94% (Zn) respectively. The distribution ratios of these metals, as obtained by the extraction chromatography of the TOA–carbon tetrachloride (Kel-F)–HCl system, were in quite good agreement with those obtained by the batch extraction.
The Analytical Application of Sulfur Analogues of β-Diketones. V. Some Aspects of the Extraction Behavior of STTA (1,1,1-Trifluoro-4-(2-thienyl)-4-mercapto-3-buten-2-one) Complexes and Their Adducts with TOPO
Authors: Honjo Takaharu , Yashima Satoshi , Kiba Toshiyasu
Published: July 2006

The solvent extraction of trace amounts of various metal ions with STTA (1,1,1-trifluoro-4-(2-thienyl)-4-mercapto-3-buten-2-one) in the presence or in the absence of TOPO (tri-n-octylphosphine oxide) has been investigated. The results are as follows: (a) The apparent extraction constant of each metal–STTA chelate in cyclohexane, logK, increases, and their pH 1⁄2 values decrease, in the order of: Cd(II)-In(III)-Zn(II)-Fe(III)-Ni(II)-Ag(I)-Bi(III)-Co(II)-Pb(II)-Cu(II)-Hg(II). This order was found to hold also in the back-extraction, except for cobalt, which was not back-extracted even with 1–12 M HCl. The other metals, Au(III), and Pd(II), could also be extracted as their STTA chelates. (b) The kind of the solvent has an effect to the lowest pH value where the metal STTA chelates begin to be extracted; the lowest pH is shifted to a higher value in the order of: C6H12, CCl4, MIBK, C6H6 and CHCl3. (c) The distribution coefficient, Pr, and the enol dissociation constant, Ka, of STTA were logPr=2.99 (10−3 M STTA in cyclohexane-0.1 M NaClO4-pH 1.0) and logKa=−4.38 (10−4 M STTA in 0.12 M HCl, 0.1 M CH3COOH (pH 4.5) and 0.1 M NaOH-C2H5OH (1/5, v/v) solution) at 20 °C. (d) The extraction equilibrium of Zn seemed to be rapid, that of Ni showed its rate-determining step to be the formation of Ni(STTA)+, and that of Co seemed to be accompanied by a transformation of Co(STTA)2 to Co(STTA)3. (e) In the metal–STTA(0.001 M)-TOPO(0.01 M)–cyclohexane system, the |ΔpH1⁄2| was found to be 0.45 for Ni, 1.95 for Zn, and 0.25 for Co. The Co–STTA–TOPO chelate could be back-extracted to some degree with 1 M HCl. The extracted species were ascertained to be Zn(STTA)2, Zn(STTA)2TOPO, Ni(STTA)2, Co(STTA)2, Co(STTA)3, and Co(STTA)2TOPO. The stability constant of Zn(STTA)2 TOPO was found to be 6.05.
Polarographic Behavior of 9-Nitroanthracene and 9,10-Dinitroanthracene in Dimethylformamide
Authors: Kitagawa Toyokichi , Ichimura Akio
Published: July 2006

The polarographic behavior of 9-nitroanthracene and 9,10-dinitroanthracene has been studied in dimethylformamide. 9-Nitroanthracene shows consecutive two one-electron diffusion-controlled reduction waves followed by fast chemical reactions. 9,10-Dinitroanthracene, however, shows only one reversible two-electron diffusion-controlled wave. The effect of the supporting electrolyte cation on these reduction waves was also investigated. In alkali metal or alkaline earth metal perchlorate as a supporting electrolyte, the half-wave potentials shift to the anodic side. The relationship between the half-wave potential and the ionic potential of the cation was discussed.
Group Interactions in Polyelectrolytes. VI. Animation Kinetics of Chloromethylated Polystyrene in N,N-Dimethylformamide and Dimethyl Sulfoxide
Authors: Kawabe Hiroshi , Yanagita Masaya
Published: July 2006

Although the apparent second-order rate constant of the amination of chloromethylated polystyrene with n-butylamine or with 2-aminobutanol decreased or increased, respectively, during the course of the amination in dioxane, as has been reported previously, both animations as well as the aminations of benzyl chloride have been found to conform to the ordinary second-order kinetics in DMF and DMSO. The viscometric measurements have indicated that the viscosity of the reaction mixture decreased during the amination with n-butylamine and increased slightly during the amination with 2-aminobutanol, but no relation between the kinetic behavior and the viscometric changes in the reaction mixtures could be found. The magnitude of the rate constants was comparable to that of the amination of benzyl chloride, and it increased with an increase in the dielectric constant of the solvents in this order: dioxane<<DMF<DMSO. The effects of the solvents on both the kinetic behavior in the aminations of the polymer and the magnitude of the rate constants have been discussed in terms of the interactions between the solvent and the solute molecules.
Oxidation by Transition Metal Complexes. VI. Oxidation of Cyclohexenes Catalyzed by Rhodium Complexes
Authors: Kaneda Kiyotomi , Itoh Takashi , Fujiwara Yuzo , Teranishi Shiichiro
Published: July 2006

Rhodium complexes can cause the catalytic oxidation of cyclohexene to give ketone, alcohol, and epoxide. The product distribution is dissimilar to that of the metal-catalyzed decomposition of cyclohexene hydroperoxide(V). Ketone and alcohol are derived from the decomposition of the intermediate hydroperoxide (V) but epoxide is not formed by the oxygen transfer reaction from V. Oxidation of methylcyclohexenes was also studied and discussed in relation to the effect of methyl substituent.
An Addition Reaction of Diethylamine to Styrene Catalyzed by Lithium Diethylamide
Authors: Narita Tadashi , Yamaguchi Teruo , Tsuruta Teiji
Published: July 2006

An addition reaction of diethylamine to styrene catalyzed by lithium diethylamide was found to proceed stoichiometrically to produce 1-diethylamino-2-phenylethane. The rate of the reaction was expressed by the equations: υ=k[Styrene][Et2NLi]1.3 and υ=k[Styrene][Et2NLi], the ratios of [Et2NH]0 to [Et2NLi]0 being 3.0 and 10 respectivly. On the basis of the kinetic studies, the mechanism of the addition reaction was elucidated. The nucleophilic character of this reaction was clearly demonstrated by the σ–ρ Hammett plot. The second-order rate constant for the addition reaction of styrene was found to be of the same order of magnitude as that of butadiene. The presence of butadiene in the reaction system showed no effect on the reactivity of styrene.
Layered Compounds. XVI. NMR Spectra of Multilayered [2.2]Paracyclophanes
Authors: Otsubo Tetsuo , Mizogami Shigeyoshi , Sakata Yoshiteru , Misumi Soichi
Published: July 2006

The NMR spectra of multilayered [2.2]paracyclophanes (I–XVI), in which benzene rings are closely stacked, have been examined. The assignment of the signals was made not only by integral strength, but also by solvent effect and the Nuclear Overhauser effect. The steric compression effect of transannular methyl groups on aromatic protons was observed in methylated cyclophanes. Enhanced ortho substitution shift was also observed. All the aromatic protons shift to remarkably higher field due to the anisotropy of stacked benzene rings as the number of layers increases. The shielding effect caused by these rings was empirically estimated.
Aminocyclitols. XXIX. Synthesis of Inosadiamines via 1,3-Biimino-1,3-dideoxy-inositols
Authors: Suami Tetsuo , Ogawa Seiichiro , Uchino Hayashi , Uchida Masaru
Published: July 2006

Hydrazinolysis of Dl-1,4-dibromo-1,4-dideoxy-chiro-inositol (3a), followed by catalytic hydrogenation and acetylation, afforded di-N-acetyl-tetra-O-acetyl-neo-inosadiamine-1,3 (6a) and -scyllo-inosadiamine-1,3 (7) in 18% and 24% yields, respectively. From the intact hydrazinolyzate of 3a, two new stereoisomeric 1,3-biimino-1,3-dideoxy-inositols (4a and 5a) could be isolated, and their structures were established by correlating to the corresponding inosadiamines. A similar hydrazinolysis of 3,6-di-O-p-tolylsulfonyl-muco-inositol (12) gave sole crystalline 1,3-biimino compound (13a), whose structure was followed from its conversion into known di-N-acetyltetra-O-acetyl-myo-inosadiamine-4,6 (14). PMR spectra of four 1,3-biimino compounds were discussed.
New Syntheses of Pyrimido[4,5-d]pyrimidines
Authors: Yoneda Fumio , Higuchi Masatsugu
Published: July 2006

Novel conversions of pyrrolo-pyrimidines into pyrimido-pyrimidines are described. The treatment of 5-nitrosopyrrolo-pyrimidine (I) under Beckmann conditions causes ring expansion to give pyrimido-pyrimidine (II). Both the reduction of I with triphenylphosphine, potassium pyrosulfite, or sodium dithionite in dimethylformamide and the oxidation of 5-aminopyrrolo-pyrimidine with lead tetraacetate in dimethylformamide or acetic acid afford II. 5-Aminopyrimido-pyrimidine is prepared by the nucleophile-induced ring expansion of I. The possible mechanisms of these ring expansions are proposed.
Condensation Reactions of Adenine Derivatives with 1-O-Acetyl-2,3,5-tri-O-benzoyl-β-d-ribofuranose in Nitrophenols
Authors: Nakazaki Nobuo , Sekiya Masao , Yoshino Teruo , Ishido Yoshiharu
Published: July 2006

Intermolecular interaction between nitrophenols, such as m-, p-nitrophenol, 2,4-dinitrophenol, and picric acid, and adenine derivatives, such as N(6)-benzoyladenine, N(6)-benzoyl-2-methylthioadenine, and N(6)-benzyladenine, was verified by the formation of the corresponding molecular compounds. On the basis of these results, condensation reactions of these adenine derivatives with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-d-ribofuranose were carried out in nitrophenols, which were used as the activating agents. They were proved to afford the corresponding nucleosides in good yields. In addition, a novel glycosyl rearrangement reaction was first observed in the case of the reaction of N(6)-benzyladenine with the ribofuranosyl acylate.
Tri(hetero)substituted Carbonium Ions. VIII. The Hydride Reduction of Cyclic and Open-chain Dithiocarbamidium Salts
Authors: Hiratani Kazuhisa , Nakai Takeshi , Okawara Makoto
Published: July 2006

Studies were carried out on the hydride reduction of the following five stable N,S,S-tri(hetero)substituted carbonium ions: N,N,S,S′-tetramethyldithiocarbamidium ion (1a), 2-dimethylamino-1,3-dithiolanylium ion (1b), 2-dimethylamino-1,3-dithianylium ion (1c), 2-methylthio-3-methyl-4,5-dihydrothiazolium ion (1d), and 2,3,5,6-tetrahydrothiazolo[2,3-b]thiazolium ion (1e). Sodium dihydrobis(methoxyethoxy)aluminate (RDB) was found to be a suitable reducing agent. The RDB reduction of the carbonium ions at −5 °C gave the corresponding formamide thioacetals (2) in moderate yields. This provides a practical method for the synthesis of formamide thioacetals. The RDB reduction of 1d at higher temperature, however, yielded abnormal products, thiazolin-2-thione (3) and thiazolidine (4) instead of the formamide thioacetal (2d). The mechanism for the formation of 3 and 4 has been discussed in terms of the ambident character of the cation (1d). Pyrolytic reactions of the thioacetals (2) and unsuccessful attempts to abstract the methine proton of 2b by various bases are also described.
The One-Electron Reduction of Carbonium Ions. V. A Kinetic Study on the Reduction of the Substituted Cyclopropenium Ions with Cr(II)
Authors: Okamoto Kunio , Komatsu Koichi , Hitomi Akira
Published: July 2006

The one-electron reduction of a series of phenyl- and/or n-propyl-substituted cyclopropenium ions with Cr(II) has been carried out in a 10% HCl solution. The reduction of triphenylcyclopropenium (Ia), diphenyl-n-propylcyclopropenium (Ib), and phenyldi-n-propylcyclopropenium (Ic) ions quantitatively gives dimers of the respective cyclopropenyl radicals, i.e., the bis(cyclopropenyl) derivatives, whereas the tri-n-propylcyclopropenium ion (Id) is quite unreactive. A kinetic study has shown that the reactivity of these stable carbonium ions toward the one-electron reductant (Cr(II)) is lowered with a decrease in the number of the phenyl substituent: k225°C=3.0×10−4l/g-ion·s for Ia, 2.7×10−6l/g-ion·s for Ib, 2.8×10−9l/g-ion·s for Ic, and <10−11l/g-ion·s for Id. The added NaCl was found to accelerate the reduction rate of Ia, whereas the added HCl showed an initial rate enhancement effect, followed by a slight rate-retarding effect. A plot of logk2 against the electron affinities of the respective cations, estimated from the transition energies of the charge-transfer bands for Ia,b with pyrene, has been found to fit a linear correlation previously obtained for a series of tropylium ions. The values of logk2 also exhibit a linear free-energy relationship with the pKR+ of these cations.