Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 41 , Issue 11
Showing 1-50 articles out of 73 articles from the selected issue
  • Shigeyuki Aono, Masahiko Suhara
    1968 Volume 41 Issue 11 Pages 2553-2557
    Published: 1968
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    A theoretical investigation is made into the solvent and temperature effects on the proton hfs in the ESR spectra of such organic radicals as:
    (Remark: Graphics omitted.)
    where X stands for the CH3 group, in several solvents. Both effects are explained on the assumption that a molecular complex is formed between radical and solvent, so that the charge-transfer occurs from radical to solvent: The solvent effect is caused by the fact that, in various solvent molecules, slight changes take place in their lowest vacant levels, which are occupied by the electron transferred from the radical; on the other hand, the temperature effect is explained by the thermal motion of the molecules, which changes the probabilities of the radical being in the solvated state and in the free state.
  • Sadao Tanaka, Takaharu Onishi, Kenzi Tamaru
    1968 Volume 41 Issue 11 Pages 2557-2562
    Published: 1968
    Released: March 27, 2006
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    The decomposition of formic acid was studied over two sorts of metal phthalocyanines: Mg-and Fe-phthalocyanines. The rates of the decomposition reactions over Mg-Phc and Fe-Phc were proportional to the pressure of formic acid, and the decomposition proceeded to dehydrogenation as well as to dehydration over these phthalocyanines. The isotope distribution in the hydrogen (H2, HD, and D2) produced by the decomposition of HCOOD leads to the conclusion that the hydrogen molecule is mainly formed between the hydrogen atom bonded to the carbon atom and that bonded to the oxygen atom in the formic acid molecule. Formic acid was adsorbed to a considerable extent over Mg-Phc in the temperature range between 70°C and 220°C. The amount of formic acid adsorbed obeyed the Langmuir adsorption isotherm, and the infrared spectra demonstrated the presence of the formate ion HGOO on the Mg-Phc. It was also confirmed that Mg-Phc was hydrogenated during the course of the decomposition. The adsorption during the catalytic reaction was also measured. These measurements revealed that the overall rate of the reaction is proportional to the amount of formic acid adsorbed. The mechanism of formic acid decomposition was discussed on the basis of these results.
  • Kenichi Okamoto, Yo Hasegawa, Shigekazu Kusabayashi, Hiroshi Mikawa
    1968 Volume 41 Issue 11 Pages 2563-2570
    Published: 1968
    Released: March 27, 2006
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    The sensitization of the photoconductivity of PVCz by dyes was investigated by the measurement of the characteristics of the decay of the surface charge put on the polymer films. MG was selected as a dye and the following three systems were measured and the degree of the sensitization was compared; i. e., PVCz-MG, copolymer of VGz and VMG and PVCz-PVMG systems. The sensitization was observed in the wavelength region from 300 to 1200 mμ. Sensitization in the visible region was larger than in the ultraviolet. The copolymer system was inferior to the PVGz-MG system, probably because of the large loss of the carriers by the recombination and trapping in the bulk. There was the optimum concentration of the dyecontent, probably because of the disturbing effect of the dye molecule for the migration of the carriers. To make sure this point, the inhomogeneous films with the dye only on the surface were investigated. The results were explained by the difference in the distiribution of the centers of carrier generation and those of recombination and trapping of the carriers in the bulk.
  • Masahiro Matsushima, Masaaki Fukatsu, Michio Kurata
    1968 Volume 41 Issue 11 Pages 2570-2574
    Published: 1968
    Released: March 27, 2006
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    Viscosity and light scattering measurements of poly(butylene oxide) were carried out in various solvents, including a theta solvent, isopropanol. The intrinsic viscosity vs. molecular weight relationships obtained in the range of molecular weight from 2.1×105 to 2.3×106 were:
    & [η]=3.39×10^-5M_w^0.84 in benzene at 30°C,
    & [η]=4.08×10^-5M_w^0.79 in methyl ethyl ketone at 30°C,
    & [η]=8.65×10^-4M_w^0.50 in isopropanol at 29.8°C.
    The ratio σ between the end-to-end distance of the polymer chain in the unperturbed state and that in the freely rotating state was estimated to be 1.66.
  • G. D. Menghani, G. V. Bakore
    1968 Volume 41 Issue 11 Pages 2574-2577
    Published: 1968
    Released: March 27, 2006
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    The kinetics of the reaction between peroxydisulphate and piancol catalysed by silver ions (Ag+) has been studied. The rate of peroxydisulphate disappearance was found to be dependent (i) on [S2O82−] (ii) on (Ag+). The rate is independent of the concentration of pinacol. Effects of [H+], temperature on the rate were studied. ΔE, Pz, ΔS, ΔF, etc. were evaluated. Mechanism of oxidation of pinacol based on the formation of reactive [Ag2+] is postulated.
  • Hisashi Ueda
    1968 Volume 41 Issue 11 Pages 2578-2586
    Published: 1968
    Released: March 27, 2006
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    Biphenyl and trans-stilbene were irradiated by a pulse of 300 mA×0.5 μsec in two types of solvents, alkyl halides and methyltetrahydrofuran. The spectra obtained by n-butylchloride, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,2-trichloroethane, and 1,1,2,2-tetrachloroethane were concluded to be those of the cations, while the spectra obtained by CCl4, 1,1,1-trichloroethane, and pentachloroethane were concluded to be due to something other than the cations. The spectra of o-terphenyl in 1,1,2-trichloroethane and in 2-methyltetrahydrofuran were different, the reason for this was discussed. The decay curves of the optical densities due to both the cations and the anions all exhibited first-order rates. The decay of the cation of the aromatic solute was concluded to consist of two processes, the transportation of the charged species and the neutralization of the ion pair thus formed. The rate-determining step is the neutralization process, the activation energies of which are 2.17 and 3.62 kcal/mol for trans-stilbene and biphenyl respectively. The transportation of the charged species was concluded to be not by the movements of the anion and the cation across the solution, but by the electron-trap- and hole-conductions, such as have been observed in semiconductors.
  • Masayasu Sugisaki, Hiroshi Suga, S\^{y}uzô Seki
    1968 Volume 41 Issue 11 Pages 2586-2591
    Published: 1968
    Released: March 27, 2006
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    An adiabatic Nernst-Type calorimeter with a cell for condensing a sample vapor as an amorphous state was constructed. By making use of this calorimeter, the heat capacities of the glassy, supercooled liquid, and crystalline states of methanol were measured from 20°K to 120°K. It was found that the state of methanol deposited on the chilled substrate at about 95°K from its vapor state shows a glass transition phenomenon at about 103°K accompanied with the sudden increase of heat capacity, ΔCP, amounting to 26 J/(mol°K). The drastic crystallization with the exothermic effect coming to 1.54 kJ/mol was observed near 105°K. The residual entropy for the glassy methanol was found to be 7.07 J/(mol°K). Based on these results it seems very plausible to propose that any non-crystalline solid deposited on the chilled substrate from the vapor state will show the glass transition phenomenon.
  • Masayasu Sugisaki, Hiroshi Suga, Syûzô Seki
    1968 Volume 41 Issue 11 Pages 2591-2599
    Published: 1968
    Released: March 27, 2006
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    By making use of the vapor-condensation type calorimeter, the heat capacity measurements of amorphous, cubic and hexagonal ices were made between 20°K and 250°K. The glass transition phenomenon was found near 135°K with the sudden change of the heat capacity amounting to 35 J/(mol°K). The drastic crystallization with the exothermic effect which amounts to 1.64 kJ/mol was then followed at this temperature. The transformation of the cubic crystal to the hexagonal one was confirmed to occur in the temperature region from 160 to 210°K and to proceed in two steps with the activation energies of 21.3 and 44.7 kJ/mol, respectively. The amount of the exothermic effect accompanying this transformation was found to be about 160 J/mol.
  • Yoshio Murakami, Yoshiya Kanda
    1968 Volume 41 Issue 11 Pages 2599-2603
    Published: 1968
    Released: March 27, 2006
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    The fluorescence spectrum of benzene in methylcyclohexane at 77°K has been analyzed in detail. The forbidden 0–0 band appeared weakly, and all the bands were interpreted as allowed bands except for the 0–992 band. The fluorescence spectrum has also been studied in carbon tetrachloride; the anomalous vibrational structure has been found in solutions as dilute as 10−3 M, irrespective of the cooling procedure. The correlation with the absorption and with the phosphorescence spectrum of benzene reported previously has been discussed.
  • Tsunenari Saito, Koji Takahashi, Shin Sato
    1968 Volume 41 Issue 11 Pages 2603-2608
    Published: 1968
    Released: March 27, 2006
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    The luminescence from a cyclohexane solution containing p-terphenyl irradiated with 60Co γ-rays has been quenched by various compounds. The quenching efficiencies were found to be in the following order; sulfur hexafluoride∼carbon tetrachloride>nitrous oxide>ethanol>ammonia>carbon dioxide. These compounds are known in radiation chemistry as electron scavengers or as positive-ion interceptors. Cyclopropane and ethylene have also shown an appreciable quenching ability, but n-butane has shown scarecely any. These results have been explained by assuming that ionic reactions are responsible for the luminescence from a cyclohexane-p-terphenyl scintillator.
  • Yoshinori Hasegawa, Yoshito Amako, Hiroshi Azumi
    1968 Volume 41 Issue 11 Pages 2608-2611
    Published: 1968
    Released: March 27, 2006
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    The ultraviolet absorption spectrum of quinazoline vapor due to the n–π* transition was photographed and analysed. The lowest n–π* transition has its origin at 27581 cm−1, and consists of two strong and prominent progressions, 515 and 784 cm−1. The vibrational analysis of the strong bands is reported on.
  • K\={o}z\={o} Shinoda, Masamichi Fujihira
    1968 Volume 41 Issue 11 Pages 2612-2615
    Published: 1968
    Released: March 27, 2006
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    Enthalpy and entropy of solution of non-polar solutes in water diverge strikingly from the normal behavior established for regular solutions. This abnormality has been considered mostly due to the iceberg formation around solute molecules in water. The abnormal solubility and enthalpy and entropy of solution of non-polar solutes in water have been explained coherently by the extension of the regular solution theory, taking into account the iceberg formation of water molecules. Unlike currently accepted views on the hydrophobic bonding, it is concluded that the enthalpy of mixing (interchange) of non-polar solute with water is large, but the enthalpy decrease due to the iceberg formation of water largely cancels the enthalpy increase of mixing (interchange). Thus, the apparent enthalpy of solution is small or negative at low temperature. It is concluded that 1) the small solubility of non-polar solutes in, water is not an entropy effect, and 2) the solubility of non-polar solutes is promoted by the iceberg formation of water molecules.
  • Yôichi Iida, Yoshio Matsunaga
    1968 Volume 41 Issue 11 Pages 2615-2619
    Published: 1968
    Released: March 27, 2006
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    Nine Würster salts derived from p-phenylenediamine, benzidine, and their N-methyl derivatives were examined for diffuse reflection spectra and classified into three groups, namely, those showing a strong charge-transfer band similar to that in the solution’s dimer spectrum, those showing a strong α-band characteristic of the monomer and a relatively weak charge-transfer band, and, finally, those showing a spectrum which bears no resemblance to either the monomer or dimer spectrum. The mode of intermolecular interaction in these cation-radical salts was speculated upon on the basis of the spectra and the magnetic susceptibilities.
  • M. Hasan, K. Kumar, S. Dubey, S. N. Misra
    1968 Volume 41 Issue 11 Pages 2619-2623
    Published: 1968
    Released: March 27, 2006
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    The reactions of isopropoxide of praseodymium and neodymium with benzoylacetone, dibenzoylmethane have been studied and the derivatives of the type M(O–iPr)2(lig.), M(O–iPr)-(lig.)2 and M(lig.)3 (where lig.=benzoylacetone or dibenzoylmethane) have been isolated. The isopropoxide-diketonates on treatment with tertiary butanol interchange their isopropoxide group with tertiary butoxide group. Anhydrous acetylacetonates of lanthanum, praseodymium, neodymium and samarium have been prepared from the reactions of the alcoholic solution of the chlorides with alcoholic solution of ammonium acetylacetonates. The molecular weights of these β-diketonates and alkoxides β-diketonates have been measured ebullioscopically in boiling benzene.
  • Kazuo Gora, Eishin Kyuno, Ryokichi Tsuchiya
    1968 Volume 41 Issue 11 Pages 2624-2627
    Published: 1968
    Released: March 27, 2006
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    Three copper(II) complexes with maleic acid, [Cu mal(H2O]) (I) (mal=C2H2(COO)2), [Cu(Hmal)2(H2O)4] (II) and [Cu2(Hmal)4]·H2mal·4EtOH (III) (EtOH=C2H5OH), were synthesized. Compound I was prepared from an aqueous solution of copper(II) sulfate pentahydrate and sodium hydrogenmaleate at room temperature as fine blue crystals. Compound II was prepared by adding little by little copper(II) hydroxide or copper(II) hydroxycarbonate to an aqueous solution of maleic acid at a temperature below 0°C in an ice-salt bath, obtaining light-blue powdered crystals. Compound III was prepared by heating a mixed alcoholic solution of maleic acid anhydride, copper(II) sulfate pentahydrate and sodium carbonate anhydride (3:1:1) in a flask with a reflux condenser for two hours. Fine bluish-green crystals were obtained. By using copper(II) hydroxide instead of copper(II) sulfate in the above preparation, a better yield can be obtained. The effective magnetic moments of I and II were 2.00 B. M. (20°C) and 1.97 B. M. (20°C), respectively, which are relatively close to the spin-only value of the divalent copper ion. On the other hand, the magnetic moment of III was subnormal, being 1.12 B. M. (18°C). The reflection spectrum of III gave a shoulder near 370 mμ, which is specific to green copper complexes. The product (IV) obtained by the thermal decomposition of I at 220°C and the product (V) obtained from II at 160°C, which are presumed to have the chemical formula [Cu-mal(H2O)0.1] and [Cu(Hmal)(mal)1⁄2], respectively, gave normal magnetic moments, 1.91 and 1.89 B. M. (20°C). However, product (VI), obtained by expelling the alcohol from III had a magnetic moment of 1.31 B. M. (17°C). Different from the corresponding copper(II) phthalate complexes, no green copper complexes having subnormal magnetic moments could be obtained through dehydration of the blue maleate complex I or the light-blue complex II having normal magnetic moments.
  • Muraji Shibata, Isao Tanabe, Kinnosuke Okuda, Kazuo Kadota
    1968 Volume 41 Issue 11 Pages 2627-2631
    Published: 1968
    Released: March 27, 2006
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    The separation of rare earth elements by ion exchange was studied. The new eluting agent consists of an aqueous solution of diammonium hydrogencitrate and an aqueous ammoniaacetic acid mixture; the two solutions were mixed in definite ratios. Using a column of Dowex 50 W resin, the separation of Sm, Nd, Pr, Ge and La was successfully achieved. As practical samples, mixed chlorides obtained from monazite concentrates were used. Both the purities and the yields of the recovered rare earths were greater than 99%. This eluting agent was applied to the separation of yttrium-group rare earths such as Dy, Er, Yb and Y, but the attempt was not successful.
  • Susumu Nakashima, Haruo Miyata, Kyoji Toei
    1968 Volume 41 Issue 11 Pages 2632-2636
    Published: 1968
    Released: March 27, 2006
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    The acid dissociation constants of phenyl, o-, m-, and p-sulfophenyl-, o-carboxyphenyl-, o-phenol- and o-arsonophenylazochromotropic acid and the formation constants of their 1:1 metal chelates with alkaline earth metals have been measured by potentiometric titration. The measurements have been carried out at 25°C and μ=0.10 (KNO3). The influence of these substituents on the acid dissociation constants of the reagents, and on the chelate formation constants was discussed. The dissociation constants of the naphtholic protons of the o-substituted reagents increase as follows: o-OH<o-AsO(OH)2<o-COOH<o-SO3Na<o-H. The metal chelate stabilities of o-phenol-, phenyl- and o-arsonophenylazochromotropic acids decrease as follows: Mg>Ca>Sr>Ba, while for chelates of o-carboxyphenyl- and o-sulfophenylazochromotorpic acids the order is Mg>Ca>Sr≈Ba. The sulfonic group in o-sulfophenylazochromotropic acid, in spite of its remarkable electron-withdrawing effect, depress the acid dissociation, and form more stable barium chelate than phenyl-, m- and p-sulfophenylazochromotropic acid do. The plot of the formation constants, logK, against the sum of the dissociation constants, pKA(=pka1+pka2+pka3), was approximately linear.
  • Yoshinobu Takegami, Toru Ueno, Toshimitsu Suzuki, Yuichi Fuchizaki
    1968 Volume 41 Issue 11 Pages 2637-2640
    Published: 1968
    Released: March 27, 2006
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    The possibility of mass spectral analysis of less volatile and air sensitive organometallic compunds has been studied with an electron-impact, Muttauch-type mass spectrograph. Several organotitanium compounds, (C5H5)2Ti, (C5H5)2Ti-methylacetylene complex, (C5H5)2Ti-allylchlorideand (C5H5)2TiCl2-AlEt2Cl complex, have been subjected to mass spectral analysis, and the parent ion has been detected for each compound. The (C5H5)2Ti-methylacetylene complex gave a parent ion of (C5H5)2Ti(C3H4)2+; NMR and IR suggested the structure as a five-membered cyclic diene complex of (C5H5)2Ti. The (C5H5)2Ti-allylchloride gave a parent ion of (C5H5)2-Ti(C3H5)+ which proves the existence of allyl complex of (C5H5)2Ti. The (C5H5)2TiCl2-AlEt2Cl complex gave a parent ion of (C5H5)2TiCl2AlEtCl+ which is in agreement with the composition reported in the literature.
  • Goro Yamaguchi, Yasushi Kubo
    1968 Volume 41 Issue 11 Pages 2641-2645
    Published: 1968
    Released: March 27, 2006
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    A sulfur-containing sodalite-type aluminosilicate, 6NaAlSiO4·Na2S (designated sulfosodalite in this paper), was synthesized in the system NaAlSiO4-Na2S at temperatures 850 to 950°C in an H2 or N2 atmosphere. All of the sulfur in this substance was contained as sulfide ion S2−, and its equilibrium content in a unit cell increases with temperature from 1.5 S at 850°C to 1.8 S at 950°C. This substance was only pale colored, yellowish or pinkish, but the partial substitution of Si for Al produced a deep vermilion red color.
  • Goro Yamaguchi, Yasushi Kubo
    1968 Volume 41 Issue 11 Pages 2645-2650
    Published: 1968
    Released: March 27, 2006
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    Ultramarine was synthesized in the systems NaAlSiO4-Na2S and NaAlSiO4·aNa2O-Carbon under a sulfur vapor pressure controlled between 0 and 1 atm. The average valence of sulfur contained in ultramarine changed from 2.0 to 1.0 with increase in sulfur vapor pressure. This was due to the formation of a sulfide containing monosufidic sulfur ion at 0 atm and of a polysulfide containing disulfidic ion at elevated sulfur vapor pressures. Sigmoidal characteristics were observed in the relationships between the sulfur content of ultramarine and the sulfur vapor pressure.
  • Akiko Satô, Shin Suzuki
    1968 Volume 41 Issue 11 Pages 2650-2656
    Published: 1968
    Released: March 27, 2006
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    The absorption spectra of trivalent uranium in hydrochloric, sulfuric and perchloric acid solutions were investigated. It was found that there is a possibility of the formation of a chloro-complex from the fact that a large change in absorption spectra was observed at high concentrations of chloride ion. On the basis of the above facts, the behavior of trivalent uranium in those media toward ion exchange resin was studied. It was considered that an anionic complex of trivalent uranium begins to form at concentrations of hydrochloric acid above 7 N, which shows good agreement with results obtained on trivalent ions of plutonium, americium and curium, which are similar actinide elements. However, it was not possible to confirm the existence of a soluble carbonate complex of trivalent uranium, as in the case of trivalent plutonium or americium.
  • Tsunenobu Shigematsu, Masayuki Tabushi, Masakazu Matsui, Megumu Munaka ...
    1968 Volume 41 Issue 11 Pages 2656-2660
    Published: 1968
    Released: March 27, 2006
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    Stability constants of the 1:1-adducts with heterocyclic Lewis bases on copper chelates of six β-diketones and two ethylesters of β-ketoacids (Cu(ligand)2·base) were determined by spectrophotometric measurements in visible region and the effects of β-diketone substituents, Lewis bases and organic solvents on the stability constants were studied. Terminal alkyl groups of β-diketones hardly hindered the adduct formation, because the adducts of β-diketone chelates except acetylacetone chelate had similar stability constants. Solvent effect was due to the formation of the solvates of the chelates or the solvation of N-base with solvent. This is related to the abnormal position of chloroform in the order of the adduct stability compared with oxygencontaining solvents. Infrared spectra indicate that the metal-oxygen bonding, as well as the basicity of Lewis bases is considered as an essential factor in the adduct formation of metal β-diketone chelates.
  • Yoshinaga Oka, Toyoaki Kato, Koichi Nomura, Tatsuya Saito, Hui-Tuh Tsa ...
    1968 Volume 41 Issue 11 Pages 2660-2662
    Published: 1968
    Released: March 27, 2006
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    The yields of the (γ, α) reactions on 7 elements up to an atomic number of 49, irradiated with 20 MeV bremsstrahlung, have been obtained through gamma-ray spectrometric measurements of the resultant activities. The yield values, as measured in absolute disintegration rates at the end of irradiation per mole per roentgen, have been plotted against atomic number of the target nuclides. The yield curve shows a maximum in the region of copper and zinc, and drops rapidly with increasing atomic number. The shape of this yield curve is similar to that for the photoalpha yield as a function of atomic number. It can be seen that the yield levels off in the region of silver and indium. A mechanism such as the direct photoelectric effect is thought to be responsible for this behavior. The yield of the (γ, α) reaction of an element amounts to only a small fraction, at most a few tenths of a per cent, of the total photonuclear yield.
  • Tosaku Susuki, Kikuhiko Koyama, Akira Omori, Shigeru Tsutsumi
    1968 Volume 41 Issue 11 Pages 2663-2668
    Published: 1968
    Released: March 27, 2006
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    The anodic reaction between cyanide ions and monosubstituted benzenes in methanol has been investigated. An examination of the products has indicated that the reaction proceeded by means of the formation of nucleus-cyanated products. The solvent perhaps also participates concurrently in this anodic reaction leading to the formation of methoxylated compounds. The results offer a striking contrast in isomer distribution between these two substitutions. The substituents on the benzene rings had a pronounced effect on the yield of the cyano compounds. The reactivity of the aromatic compounds toward the anodic cyanation decreased in the following order:
    anisole >> toluene > ethylbenzene > cumene >> benzene >> methyl benzoate.
    These results have been interpreted as resulting from the generation of an aromatic ion radical at an anode by the loss of a π-electron from each molecule.
  • Kikuhiko Koyama, Tatsuyoshi Ebara, Shigeru Tsutsumi
    1968 Volume 41 Issue 11 Pages 2668-2671
    Published: 1968
    Released: March 27, 2006
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    The anodic reaction of benzoic acid in acetonitrile containing tiethylamine was carried out in the presence of toluene, ethylbenzene, cumene, and tetralin. The amounts of carbon dioxide evolved during the electrolyses were smaller than those expected to be produced through the spontaneous decomposition of the benzoyloxy radical. An examination of nongaseous products indicated that the anodic reaction proceeds by means of the formation of the benzoyloxylates and phenylates of the aromatic hydrocarbons present. The occurrence of the nuclear benzoyloxylation, to a relatively great extent, suggested that the aromatic hydrocarbons were oxidized at the anode.
  • Shoichi Matsumura, Toshikazu Nagai, Niichiro Tokura
    1968 Volume 41 Issue 11 Pages 2672-2675
    Published: 1968
    Released: March 27, 2006
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    The present paper deals with the decomposition reaction of episulfones in the presence of several bases. The treatment of cis-stilbene episulfone (I) with 2 N NaOH gave trans-stilbene in a 92% yield, and a hydrogen-deuterium exchange experiment using NaOD showed that 66% of the methine protons of the episulfone were exchanged. On the other hand, the reaction of n-butyllithium yielded cis-stilbene predominantly, along with trans-1,2-diphenylvinyl sulfinate in about a 20% yield. Styrene episulfone (II) gave styrene (80%) and a trace of benzyl methyl sulfone when II was treated with alkali. Tetraphenylethylene episulfone (III) afforded tetraphenylethylene almost quantitatively. The cleavage mechanism by bases is then discussed on the basis of the above results. Ethylene episulfone (IV) is oligomerized by tertiary-amine catalysis.
  • Yoshiyuki Kawase, Mutsumu Nanbu, Fumihisa Miyoshi
    1968 Volume 41 Issue 11 Pages 2676-2682
    Published: 1968
    Released: March 27, 2006
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    The acylation of 2,3-dimethyl-4-hydroxybenzofuran (1) with acetic acid, phenylacetic acid, 2-methoxyphenylacetic acid or 2,4,5-trimethoxyphenylacetic acid, and polyphosphoric acid gave a mixture of the 5- and 7-acyl compounds (2a, b, c, d, and 3a, c, d respectively). Analogously, the isomeric 2,3-dimethyl-6-hydroxybenzofuran (6) gave the 5-acyl compounds (7a, b, c, d), two (7a, b) of which were also obtained by the Friedel-Crafts acylation of the methyl ether of 6 (9), followed by demethylation. On the other hand, the formation of a dimethylfuran ring on 2,4-dihydroxyphenyl ketones by the action of polyphosphoric acid on their 4-(α-acetylethoxy) derivatives (11a, b, c) also afforded mixtures of the ketones (7a, b, c) and isomeric ketones (2a, b, c). The benzofuranyl ketones (2 and 7) thus obtained were converted to the corresponding 4″,5″-dimethyl-furo[2″,3″:7,8]isoflavones (12b, c, d) and isomeric -furo[3″,2″:6,7]isoflavones (14b, c), and also their 2-methyl derivatives (13b, c, d and isomeric 15b, c), by the general method utilizing ethyl orthoformate, piperidine and pyridine, or acetic anhydride and sodium acetate. The furoisoflavones (12b, c and 13b, c) were also prepared by building up the dimethylfuran ring on 7-hydroxyisoflavones by the action of polyphosphoric acid or sulfuric acid on their 7-(α-acetylethoxy) derivatives (16b, c and 17b, c respectively). The alkaline degradation of these furoisoflavones (12 and 13) also gave the benzofuranyl ketones (2).
  • Yoshiyuki Kawase, Mutsumu Nanbu, Fumihisa Miyoshi, Hiroshi Kawamura
    1968 Volume 41 Issue 11 Pages 2683-2689
    Published: 1968
    Released: March 27, 2006
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    4′,5′-Dimethyl-4-hydroxyfuro[2′,3′:7,8]coumarin (2) and its 3-phenyl, 3-(2-methoxyphenyl), and 3-(2,4,5-trimethoxyphenyl) derivatives (4, 5 and 6), and also their isomers, 4′,5′-dimethyl-4-hydroxyfuro[3′,2′:6,7]coumarins (14, 15, 16 and 17), were prepared by the action of ethyl carbonate or of ethyl chlorocarbonate on the corresponding 2,3-dimethyl-4- or isomeric 6-hydroxy5-benzofuranyl ketones. Two furocoumarins (2 and 14) were also obtained in poor yields by the condesnation of 2,3-dimethyl-4- or 6-hydroxybenzofuran with malonic acid. The action of hydroiodic acid on the furocoumarins 5 and 6 afforded 2,3-dimethyl-5H-benzofuro[3,2-c]furo[2,3-h][1]benzopyran-5-one (8) and its 7,8-dihydroxy derivative (9) respectively; 8 was also synthesized by building up the dimethylfuran ring on 3-hydroxy-6H-benzofuro[3,2-c][1]benzopyran-6-one, while 9 was also synthesized by the oxidative coupling of 2 with catechol. On the other hand, the action of pyridine hydrochloride on 5 caused the closure of the furan ring towards the 2-position, giving l,2-dimethyl-6H-benzofuro[2,3-b]furo[2,3-h][1]benzopyran-6-one (11), which had a new pentacylic ring system; the only demethylated compound (12) was also obtained. The structure of 11 was confirmed by its IR and UV spectra and by the formation of 12 upon its alkaline hydrolysis. The action of aluminum chloride on 5 also gave 12. Analogously, isomeric l,2-dimethyl-6H-benzofuro[3,2-c]furo[3,2-g][1]benzopyran-6-one (20) and its 8,9-dihydroxy compound (21) were also synthesized.
  • Fuminori Akiyama, Niichiro Tokura
    1968 Volume 41 Issue 11 Pages 2690-2695
    Published: 1968
    Released: March 27, 2006
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    The acylations of l-menthol with p-substituted benzoyl- and substituted acetyl chlorides were carried out, and it was found that the electron-releasing substituents accelerate the reaction rate in chloroform even though the reaction is completely of the SN2 type. This result is interpreted in relation to the low isokinetic temperature, the reaction itself being carried out above that temperature. Such a phenomenon is discussed in terms of the configurational and the solvent effects on the entropy of activation.
  • Shuichi Seto, Kyozo Ogura, Hiroko Toda, Yusaku Ikegami, Tsuneo Ikenoue
    1968 Volume 41 Issue 11 Pages 2696-2699
    Published: 1968
    Released: March 27, 2006
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    Bromination of 5-amino-2-methoxytropone and 2-amino-7-methoxytropone afforded 5-amino-4-bromo-2-methoxytropone and 2-amino-3,5-dibromo-7-methoxytropone, respectively, as expected from the consideration of the effect of amino group in 2-methoxytropone system. Long-range spin coupling between the methoxyl group and a neighboring ring proton was observed in 2-methoxytropone derivatives. This information was applied to elucidation of the structure of the bromination products. The comparison of their NMR spectra gave the reasonable assignment for the ring protons of 5-amino-2-methoxytropone.
  • Jun Katsuhara
    1968 Volume 41 Issue 11 Pages 2700-2703
    Published: 1968
    Released: March 27, 2006
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    The conversion of (−)-pinocarvone oxide derived from (+)-pinocarvone into (−)-(1R:2S:3R:5R)-cis-2-hydroxypinocampheol and the conversion of (+)-pinocarvone oxide in (+)-(1R:2R:3R:5R)-trans-2-hydroxyneoisopinocampheol and (−)-(1R:2R:3R:5R)-cis-2-hydroxyisopinocampheol are described. With the knowledge of the absolute configurations of these glycols, it was concluded that (−)-pinocarvone oxide and (+)-pinocarvone oxide have the (1R:2S:5R)- and (1R:2R:5R)-configurations, respectively.
  • Teruaki Mukaiyama, Harumi Katsuyama
    1968 Volume 41 Issue 11 Pages 2703-2706
    Published: 1968
    Released: March 27, 2006
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    The reactions of mercuric carboxylates with bivalent sulfur compounds, such as aralkyl sulfides and mercaptoles, were investigated. When mercuric acetate and aralkyl sulfides were refluxed in benzene, mercury mercaptides and aralkyl acetates were obtained. It was made clear that the reactivity of the sulfides depends on the stability of carbonium ions given by elimination of the mercapto group. Next, it was found that acetic anhydride, benzophenone and mercury phenylmercaptide were obtained in high yields by the equimolar reaction of benzophenone diphenylmercaptole with mercuric acetate. Further, the reaction was extended to the preparative method of carboxylic acid anhydrides from free acids by treating the carboxylic acids with diphenylmercury and the mercaptole. On the other hand, S-phenyl thioacetate, benzophenone and mercury mercaptide were produced in good yields when benzophenone diphenylmercaptole (2 mol) was treated with mercuric acetate (1 mol). Further, it was established that thiolesters were exclusively produced in good yields along with benzophenone and the mercury mercaptide by the reaction of benzophenone diphenylmercaptole or bis (p-chlorophenyl) mercaptole (2 mol) with free carboxylic acids (2 mol) and diphenylmercury (1 mol).
  • Sigeru Torii, Siro Endo, Hirotosi Oka, Yoshihiro Kariya, Akira Takeda
    1968 Volume 41 Issue 11 Pages 2707-2712
    Published: 1968
    Released: March 27, 2006
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    Reaction of α-carboxy-β-carbethoxy-γ,γ-dimethylbutyrolactone (3) with equimolar amount of nitrous acid gave ethyl α-hydroxyaminoaconate (7). However, the nitrosation of 3 using excess nitrous acid afforded a variety of compounds such as α-diazo (4 and 5), α-nitro (8), and α-azoxybutyrolactone (9) derivatives. Each of the products (4, 5, 8, and 9) could be synthesized from 7, independently. By the action of phosphoric acid, α-diazolactones (4 and 5) were converted into ethyl α,β-epoxyparaconate (6). The nature of the product 7 was demonstrated through its conversion into ethyl α-hydroxyaconate and through its thermal decomposition to ethyl α-aminoaconate and a-isopropylidenecyanoacetic acid derivatives. A possible mechanism for the formation of 6 through 4 and 5 is described.
  • Yoshio Otsuji, Tokuyuki Kuroda, Eiji Imoto
    1968 Volume 41 Issue 11 Pages 2713-2718
    Published: 1968
    Released: March 27, 2006
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    The irradiation of barbital (BA) and N,N′-dimethylbarbital (DMBA) in aqueous alkaline media gave diethylacetylurea and N,N′-dimethyldiethylmalonarmide respectively. On the basis of the results of kinetic studies, the above photochemical hydrolyses of BA and DMBA were shown to be an attack of the hydroxide ion on the singlet excited states of BA monoanion and DMBA respectively. Such nucleophilic reagents as amines, mercaptide, and cyanide ions retarded the photochemical hydrolyses by quenching the excited state of the substrates.
  • Kiyoshi Tanikawa, Takashi Ishizuka, Kojiro Suzuki, Shigekazu Kusabayas ...
    1968 Volume 41 Issue 11 Pages 2719-2722
    Published: 1968
    Released: March 27, 2006
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    Using Wittig’s reaction, we synthesized 3-vinylpyrene from pyrene-3-aldehyde in 76% yield. 3-Vinylpyrene monomer was polymerized by benzoylperoxide or di-t-butylperoxide catalysts. Each polymer had a melting point, being observed by the method of polarizing hot stage microscopic examination. X-ray examination showed that the polymer was crystalline, although rather poor. The charge transfer complexes, containing polyvinylpyrene as an electron donor, and iodine, tetracyanoethylene or tetracyanoquinodimethane as an electron acceptor, were prepared, each having the composition of pyrene nucleus : acceptor=16 : 3, 15 : 2, 15 : 2, respectively. Electrical conductivities of the complexes at 25°C, ρ25 and band gap energies, ε, were 1.3×108 Ωcm, 0.80 eV; 4.5×1012 Ωcm, 1.32 eV; 1.1×1014 Ωcm, 1.34 eV, respectively. Each complex showed ohmic current-voltage characteristics in an appropriate temperature range.
  • Tsuyoshi Miyazaki, Yoshio Matsushima
    1968 Volume 41 Issue 11 Pages 2723-2726
    Published: 1968
    Released: March 27, 2006
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    3-O-carboxymethyl-D-glucosamine, 6-O-carboxymethyl-D-glucosamine, and the corresponding glucosaminitols are prepared as reference compounds in a study of a lysozyme action on a partially-O-carboxymethylated chitin. The preparation of partially-O-carboxymethylated chitin, a substrate of hen-egg white lysozyme, is also described.
  • Hiroo Inoue, Nobuyuki Komakine, Eiji Imoto
    1968 Volume 41 Issue 11 Pages 2726-2733
    Published: 1968
    Released: March 27, 2006
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    Ferric chloride reacts with 1,2-glycols, when irradiated with light, to afford dehydration and dehydrogenation products. The reaction course is influenced by the structure of the 1,2-glycols, the kind of ligand around the Fe(III) ion, and the solvent in the reaction system. When the number of hydrogen atoms on carbon having a hydroxyl group of 1,2-glycol increases, the yield of the dehydration product increases in comparison with that of the dehydrogenation product; the photochemical reaction of ferric chloride with ethylene glycol or pinacol gives, selectively, acetaldehyde or acetone respectively. The photochemical reaction of ferric acetate with the ethylene glycol shows a highly selective dehydrogenation, giving only formaldehyde, though it is in a good yield. Furthermore, the addition of aniline or acetic acid to the ferric chloride-ethylene glycol system results in an increase in the production of glyoxal or acetaldehyde respectively. In the photochemical reaction of ferric chloride with ethylene glycol or cis- and trans-1,2-cyclohexanediol, acetonitrile as a solvent causes the formation of the dehydrogenation products, that is, acetoxyacetaldehyde and glyoxal or 1,2-cyclohexanedione respectively.
  • Kenji Fukui, Mitsuru Nakayama
    1968 Volume 41 Issue 11 Pages 2733-2735
    Published: 1968
    Released: March 27, 2006
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    The synthesis of dehydroneotenone has been carried out using 6-hydroxy-5-(2-methoxy-4,5-methylenedioxyphenylacetyl)-2,3-dihydrobenzo[b]furan as an intermediate and by subjecting it to cyclization with ethyl orthoformate, followed by dehydrogenation.
  • Masuo Funabashi, Juji Yoshimura
    1968 Volume 41 Issue 11 Pages 2735-2742
    Published: 1968
    Released: March 27, 2006
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    N-phényl acétone-D-glycéraldimine dimérise facilement en présence d’un soupçon de l’acide acétique et donne deux dimères, dont la structure y comprise la configuration absolue partielle a été etablie par l’analyse spectrométrique et la décomposition chimique comme étant un 4-anilino-2-(2′,2′-diméthyl-1′,3′-dioxolanne-4′-yl)-1,2,3,4-tétrahydroquinoléine-3-spiro-4″-(2″,2″-diméthyl-1″,3″)dioxolanne. Lorsqu’on hydrolyse ces dimères partiellement avec l’acide acètique aqueux á 70%, on peut isoler 1,2,3,4,5,6-héxahydro-4-hydroxy-1,5-méthano-2,6-benzoxazocine-11-spiro-4′-(2′,2′-dimethyl-1′,3′)dioxolanne avec un rendement d’environ 40% et enmême temps l’aniline est detaché. Néanmoins, le dérivé N-acétyle d’un dimère n’a pas détaché l’aniline á la même condition d’hydrolyse.
  • Takanobu Kumamoto, Kazuo Hosoi, Teruaki Mukaiyama
    1968 Volume 41 Issue 11 Pages 2742-2745
    Published: 1968
    Released: March 27, 2006
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    New methods for the syntheses of vinyl sulfides and unsaturated nitriles via quaternary phosphonium salts have been established. The reaction of isopropylidenetriphenylphosphorane with S-ethyl thiobenzoate or substituted S-ethyl thiobenzoates afforded vinyl sulfides and triphenylphosphine oxide in good yields. Further, it was found that the reaction of α-benzoylalkylphosphonium salts with sodium ethylmercaptide or potassium cyanide gave olefins, such as vinyl sulfides or unsaturated nitriles, and triphenylphosphine oxide in good yields, respectively.
  • Tsujiaki Hata, Kiyohiko Tajima, Teruaki Mukaiyama
    1968 Volume 41 Issue 11 Pages 2746-2747
    Published: 1968
    Released: March 27, 2006
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    A convenient method for the preparation of carboxylic anhydrides by use of one mole of N,N′-dicyclohexylthiourea and two moles of silver or mercurous carboxylate has been established. According to this method, several carboxylic anhydrides were obtained in high yields under mild conditions even by microscale experiments.
  • Tetsuo Shiba, Akio Koda, Shoichi Kusumoto, Takeo Kaneko
    1968 Volume 41 Issue 11 Pages 2748-2753
    Published: 1968
    Released: March 27, 2006
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    Asparagine peptide was selectively cleaved by the Hofmann rearrangement followed by an alkaline treatment at the peptide linkage in which an amino group of the asparagine residue participated. Upon reaction of N-benzyloxycarbonyl-L-alanyl-L-asparagine with one equivalent of bromine and three equivalents of aqueous sodium hydroxide solution at 60°C, 1-(N-benzyloxycarbonyl-L-alanyl)-2-oxoimidazolidine-5-carboxylic acid was obtained in quantitative yield. When this was treated with an aqueous methanolic sodium hydroxide solution at room temperature, a cleavage reaction occurred to give N-benzyloxycarbonyl-L-alanine and 2-oxo-imidazolidine-5-carboxylic acid. Under the same condition of the rearrangement, N-benzyl-oxycarbonyl-L-asparaginyl-L-phenylalanine was converted to 1-benzyloxycarbonyl-2-oxoimidazo-lidine-5-carbonylphenylalanine. Since glutamine peptide could not give the corresponding ring compound, this cleavage reaction was found to be specific to asparagine peptide.
  • Tsuyoshi Miyazaki, Yoshio Matsushima
    1968 Volume 41 Issue 11 Pages 2754-2757
    Published: 1968
    Released: March 27, 2006
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    Partially-O-carboxymethylated chitin was found to be a soluble substrate of hen egg white lysozyme. The products of the lysozyme action were analyzed by gel filtration and by ion-exchange chromatography. The reducing ends of the saccharides produced by the enzyme were the N-acetyl-glucosamine residue or the 3-O-carboxymethyl-N-acetyl-glucosamine residue. 6-O-Carboxymethyl-N-acetyl-glucosamine never appeared as a reducing end. The O-substituted disaccharide detected in the reaction products was 6′-O-carboxymethyl-di-N-acetyl-chitobiose. The results of the reducing-end analyses and the finding that none of the monomers were formed except for the unsubstituted N-acetyl-glucosamine, while an O-substituted dimer was formed as is mentioned above, are in conformity with the conformation of the enzyme-substrate complex proposed by Blake et al. as a result of their X-ray crystallographic investigations.
  • Hideaki Kurita, Yasuhiro Chigira, Mitsuo Masaki, Masaki Ohta
    1968 Volume 41 Issue 11 Pages 2758-2762
    Published: 1968
    Released: March 27, 2006
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    Treatment of N-dichloroacetyl amino acids with acetic anhydride at a temperature between 85°C and 130°C yielded 4-alkylidene- and 4-aralkylidene-2-chloromethyl-5-oxazolones, which were readily hydrolyzed to give 2-(2-chloroacetamido)-2-alkenoic acids, i.e., N-(chloroacetyl)-dehydroamino acids.
  • Go Hata, Akihisa Miyake
    1968 Volume 41 Issue 11 Pages 2762-2764
    Published: 1968
    Released: March 27, 2006
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    A zerovalent iron complex, Fe(Ph2P·CH2CH2·PPh2)2· C2H2, catalyzes addition of ethylene to butadiene to afford 1 : 1 adducts consisting of 1,cis-4-hexadiene, 1,3-hexadiene, 2,4-hexadiene and 1,5-hexadiene, and 2 : 1 adducts. The combination of the iron complex and a Lewis acid (triethylaluminum, diethylaluminum chloride, ethylaluminum dichloride and boron trifluoride etherate) gives 1,cis-4-hexadiene much more selectively. The most efficient Lewis acid component for the synthesis of 1,cis-4-hexadiene is diethylaluminum chloride.
  • Shinkiti Koto, Takayuki Tsumura, Yoshinori Kato, Sumio Umezawa
    1968 Volume 41 Issue 11 Pages 2765-2769
    Published: 1968
    Released: March 27, 2006
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    As a part of investigation of the synthesis and reaction of 1-halogeno derivatives of amino-monosaccharides, 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-D-glucopyranosyl chloride and 2,3,4-tri-O-benzyl-6-(N-benzylacetamido)-6-deoxy-α-D-glucopyranosyl chloride have been synthesized. Attempts to prepare α-glycosides from these benzyl derivatives proved to be practical, giving cyclohexyl 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-D-glucopyranoside and cyclohexyl 2,3,4-tri-O-benzyl-6-(N-benzylacetamido)-6-deoxy-α-D-glucopyranoside as main products. Removal of the masking groups gave cyclohexyl α-glucosides of 3-amino-3-deoxy-D- and 6-amino-6-deoxy-D-glucose respectively. A number of related derivatives have been described.
  • Shinkiti Koto, Kuniaki Tatsuta, Eiichi Kitazawa, Sumio Umezawa
    1968 Volume 41 Issue 11 Pages 2769-2771
    Published: 1968
    Released: March 27, 2006
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    6-O-(3-Amino-3-deoxy-α-D-glucopyranosyl)-2-deoxystreptamine (3AD) which is a glycoside component of kanamycin A has been synthesized. Amino and hydroxyl groups of 2-deoxystreptamine were masked with carbobenzoxy and isopropylidene groups to give racemic mono-O-isopropylidene-di-N,N′-carbobenzoxy-2-deoxystreptamine with which 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-D-glucopyranosyl chloride was condensed by a modified Koenigs-Knorr reaction. Removal of all the masking groups followed by N-dinitrophenylation, acetylation and chromatography gave the product identical with an authentic specimen of the penta-O-acetyl-tri-N-(2,4-dinitrophenyl) derivative of the natural 3AD. The synthetic product was further led to 3AD identical with a natural sample.
  • Haruhiko Aoyagi, Michio Kondo, Nobuo Izumiya
    1968 Volume 41 Issue 11 Pages 2772-2776
    Published: 1968
    Released: March 27, 2006
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    Two analogs of oxytocin, [9-leucine]-oxytocin and oxytocinoyl-glycinamide, in which the glycinamide residue at position 9 in oxytocin has been replaced by a leucinamide and glycyl-glycinamide, respectively, have been synthesized and tested for some of the pharmacological properties characteristic of oxytocin. The protected nona- and decapeptide intermediates were prepared by use of the azide method in a fashion of the fragment condensation. After removal of the protecting groups from the intermediates by means of either sodium in liquid ammonia or anhydrous hydrogen fluoride, the dithiols thus obtained were oxidized to the required analogs. It was found that [9-leucine]-oxytocin possessed approximately 8% oxytocic potency, and oxytocinoyl-glycinamide 0.5% potency compared with oxytocin preparation.
  • Katsuhiko Wakabayashi, Yoshio Kamiya, Nobuto Ohta
    1968 Volume 41 Issue 11 Pages 2776-2781
    Published: 1968
    Released: March 27, 2006
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    The physicochemical properties of the binary system composed of Sn and Sb oxides have been investigated. The electrical conductivity increased rapidly up to 3 atom% Sb, and subsequently decreased, little by little, as the Sb oxide content in the binary system increased. The surface area also increased rapidly up to 3 atom% Sb, and in the region exceeding this content a dilution effect due to Sb oxide was observed. The behavior of the initial rate of acrolein formation as a function of the catalyst composition was fairly similar to that of the surface area. The apparent activation energies for carbon dioxide formation at first decreased, and then became nearly constant when the Sb content of the catalysts increased. On the other hand, the activation energies for acrolein formation may be considered to be always constant, independent of the catalyst composition, at about 17 kcal/mol. The activation energies for the catalyst reduction by hydrogen were 28 kcal/mol for Sn oxide, 14 for a mixture containing 25 atom% Sb, and 30 for Sb oxide. Consequently, it has been concluded from these results that it may depend on the nature of the chemisorbed oxygen which attacks propylene whether the propylene is oxidized into acrolein or into such complete combustion products as carbon dioxide.
  • Kan-ichi Kamiya, Shigemi Yugo, Michio Inagaki, Hajime Saito, Takuro Ts ...
    1968 Volume 41 Issue 11 Pages 2782-2785
    Published: 1968
    Released: March 27, 2006
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    By means of the electron spin resonance (ESR), the graphitization process of a hard carbon (phenolformaldehyde resin char) under a pressure of 5 kbar was investigated in relation to the results of the X-ray diffraction analysis. In the ESR measurement, there is observed only a sharp Lorentzian line having g-value of about 2.003 for the products heat-treated at relatively low temperatures. On the other hand, gradual increase in the heat treatment temperature (HTT) leads to the appearance of new 15–20 G wide line having g-value of about 2.01, overlapping on the sharp one, and its absorption intensity tends to increase further with HTT. The appearance of the broad ESR line has been found always being accompanied by an abrupt increase of the content of graphitic component deduced from the analysis of (002) diffraction profile. From further investigation of features of these ESR lines as a function of ambient temperature, the sharp one is concluded that it originates from the so-called localized spin centers, while the broad one from the delocalized. The coexistence of these two signals suggests that the turbostratic and graphitic parts have enough extent to prevent the motional mixing of these spin centers, which has also been verified by the X-ray diffraction analysis.
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