Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 52 , Issue 2
Showing 1-50 articles out of 92 articles from the selected issue
  • Tsugio Kojima, Masaru Satouchi, Yasukazu Tanaka
    1979 Volume 52 Issue 2 Pages 277-280
    Published: 1979
    Released: April 19, 2006
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    In the dissociative electron capture reaction of benzyl chlorides, all the substituents in the para position except for t-butyl group tend to decrease the activation energy, those in the meta position having no influence on the activation energy. This can be explained in terms of the contribution of a para substituent to the stabilization of the incipient radical in the transition state resulting from the delocalization of the odd electron. The resonance effect of the para substituent was compared with that obtained in the phenylation of substituted benzenes with phenyl radical, where phenylcyclohexadienyl radical is formed as an intermediate. The resonance effects in these two reactions agree, supporting the reaction mechanism proposed.
  • Seiji Sawamura, Yoshihiro Taniguchi, Keizo Suzuki
    1979 Volume 52 Issue 2 Pages 281-283
    Published: 1979
    Released: April 19, 2006
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    Absorption spectra of the visible I2 band of I2 complexes with Et2O, Et2S, and Et2Se in heptane have been measured up to 3300 bar at 25 °C. The equilibrium constants and volume changes accompanying complex formation, the molar extinction coefficients and the absorption maxima have been estimated. The volume changes were found comparable with those estimated from the X-ray data of the I2 complexes in the crystalline state. The enhancement of the molar extinction coefficient and the blue shift of the visible I2 band with increasing pressure have been established. The results suggest a decrease in the bond distance between an n-donor and I2, compared with the spectroscopic properties of the I2 complex at 1 bar. The decrease has been estimated as 0.008 nm with increasing pressure up to 3300 bar.
  • Seiji Sawamura, Yoshihiro Taniguchi, Keizo Suzuki
    1979 Volume 52 Issue 2 Pages 284-286
    Published: 1979
    Released: April 19, 2006
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    Absorption spectra of the CT bands of I2 complexes with Et2O, Et2S, and Et2Se in heptane have been measured up to 4400 bar at 25 °C. The equilibrium constants and the volume changes accompanying complex formation, and the molar extinction coefficients and absorption maxima have been estimated. The volume changes were comparable with those estimated by the visible I2 bands and by the X-ray data of the I2 complexes in the crystalline state. In the CT bands of Et2S–I2 and Et2Se–I2 complexes inversion of shift from red to blue has been observed with increasing pressure though the CT band of Et2O–I2 complex shifted only through red. This inversion appears to be characteristic of the strong CT complex. Enhancement of the molar extinction coefficient of the CT band has been found with increasing pressure suggesting enhancement of the CT interaction between I2 and the n-donor.
  • Akira Imamura, Kimihiko Hirao
    1979 Volume 52 Issue 2 Pages 287-292
    Published: 1979
    Released: April 19, 2006
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    We tried to explain the electrophilicity of radical reagents such as H and OH radicals in the aromatic substitution reaction by using the molecular orbital theory. The delocalization energy of π electrons was decomposed into two parts: one is the energy due to the delocalization from a substrate to a reagent and another is that from a reagent to a substrate. The former was considered to be a measure of the electrophilicity and the latter of the nucleophilicity. The decomposition of the delocalization energy into two parts was carried out by modifying the relevant core resonance integrals as appropriate. The result indicated that the delocalization energy for the electrophilicity was much larger than that for the nucleophilicity for both radicals. Thus, H and OH radicals should be electrophilic in nature, in good agreement with the experimental facts. Finally, the origin of the electrophilicity was discussed in connection with the height of the relevant energy levels by following a perturbational approach.
  • Keiko Nishikawa, Yoshitada Murata
    1979 Volume 52 Issue 2 Pages 293-298
    Published: 1979
    Released: April 19, 2006
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    The diffraction of liquid CCl4 was measured by using the energy-dispersive X-ray diffractometer. The fine structure was observed for the first time in the present study. The existence of the fine structure in the diffraction pattern shows the long-range correlation “directly.” The bcc cluster model for liquid CCl4 is presented on the basis of the long-range correlation. The calculated intensity of the model is in good agreement with the observed one.
  • Shun-ichi Hirokami, Laszlo Wojnarovits, Shin Sato
    1979 Volume 52 Issue 2 Pages 299-301
    Published: 1979
    Released: April 19, 2006
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    The γ-radiolysis of a cyclohexene–dinitrogen oxide mixture in the liquid phase at −18 °C has been studied and the results compared with that of the radiolysis of a cyclohexene–carbon dioxide mixture in the liquid phase.5) The oxidation reaction initiated by oxygen atoms produced in the direct radiolysis of dinitrogen oxide or carbon dioxide is common for both solutions, the products being cyclohexene oxide, cylohexanone, and cyclopentanecarbaldehyde. In the dinitrogen oxide solution, however, two other oxidation processes have to be considered in order to interpret the material balance of products and the formation of other oxygenated compounds: cyclohexanol, 2-cyclohexenol, and 2-cyclohexenone. A possible reaction mechanism is discussed.
  • Jun-ichiro Take, Yoichi Tozawa, Yukio Yoneda
    1979 Volume 52 Issue 2 Pages 302-306
    Published: 1979
    Released: April 19, 2006
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    Cumene has been passed over a silica–alumina bed at low temperature (210 to 254 °C) and at cumene pressures of 0.003 to 0.023 atm. Both dealkylation and disproportionation occurred simultaneously and independently of each other. The disproportionation/dealkylation ratio increased with decrease in temperature and/or an increase in cumene pressure. The dealkylation and disproportionation reactions followed a Langmuir-Hinshelwood model with inhibition by the reactant. The dealkylation has been interpreted in terms of a unimolecular surface reaction, while the disproportionation reaction in terms of a bimolecular surface reaction. The heat of adsorption of cumene and the entropy loss of cumene on adsorption were much larger for the dealkylation sites than for the disproportionation sites. These results indicated that dealkylation was catalyzed by strong acid sites, while disproportionation by weak acid sites. The dealkylation had a much higher activation energy than the disproportionation reaction. The activation energy for dealkylation (33.5 kcal mol−1) was in good agreement with that predicted on the assumption that the previously reported LFER (linear free-energy relationship) in the alcohol dehydration holds for alkylbenzene dealkylation.
  • Tsutomu Okuda, Hideta Ishihara, Koji Yamada, Hisao Negita
    1979 Volume 52 Issue 2 Pages 307-309
    Published: 1979
    Released: April 19, 2006
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    The character of the B–X bond (X=Cl, Br, and I) in BX3–TMA complexes (TMA=trimethylamine) has been studied on the basis of the results of the nuclear quadrupole resonance (NQR). The ionic character of the B–X bond decreased in the order as expected from the electronegativity of the halogen atoms. The temperature dependence of the halogens on the NQR frequencies has been examined for BBr3– and BI3–TMA. For BBr3–TMA, all the observed resonance lines faded out far below the melting point and this has been attributed to the hindered rotation of the BBr3 group about the B–N bond, as with BCl3–TMA.
  • Takeshi Asai, Hiroshi Saheki, Ryôiti Kiriyama
    1979 Volume 52 Issue 2 Pages 310-314
    Published: 1979
    Released: April 19, 2006
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    Magnetic susceptibilities, χ, of Cu2AsO4(OH), Cu2(OH)PO4, and Cu2OSO4 have been measured from 4.2 to 360 K to establish the role of the OH and O2− ions in the magnetic superexchange interaction. The former two compounds showed a broad maximum for χ at 118 and 110 K, respectively. Although the crystal structure is three-dimensional, only a tetramer model with two parameters can explain the temperature dependence of χ, since the hydroxide anion causes a strong magnetic interaction which is limited to four copper atoms between which the anion is intermediary. The magnetic susceptibility of Cu2OSO4 obeyed the Curie-Weiss law above 140 K with a Weiss constant of −56 K. At 16 K the compound transformed into a ferrimagnetic phase, the effective megneton number of which is 0.11 at 4.2 K. A canted ferrimagnetic structure has been proposed and the canting angle estimated. In the superexchange interaction, only hydroxide and oxide anions are significant and both anions behave similarly.
  • Katsumi Kaneko, Katsuya Inouye
    1979 Volume 52 Issue 2 Pages 315-320
    Published: 1979
    Released: April 19, 2006
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    Changes in the electrical conductivity of synthetic α-, β-, and γ-FeOOH crystals with the amount of adsorbed water were measured at 30 °C and various frequencies (dc, 100–10 MHz). The conductivity variations of wateradsorbed FeOOH with temperature were also examined over the range from −140 to 140 °C. For the adsorption coverages between 0 and 0.5, the electronic conduction increased with the coverage due to the transfer of electrons from chemisorbed water molecules to the FeOOH crystal. The decrease in activation energy for conduction with chemisorption was observed. The conductivity increase due to the chemisorption is related to the characteristic surface structure of each FeOOH polymorph. In the coverage range 0.7–2, protons in the adsorbed water layer transport electrical charges. The linear relationships between the logarithm of conductivity and the logarithm of the relative pressure of water vapor suggest the presence of clusters of physisorbed water molecules on FeOOH surfaces. A steep change in protonic conductivity by a factor of 102–104 was observed at a temperature close to −5 °C. The change seems to be caused by an order-disorder transition of protons in the adsorbed water layer.
  • Yashige Kotake, Keiji Kuwata
    1979 Volume 52 Issue 2 Pages 321-323
    Published: 1979
    Released: April 19, 2006
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    Detailed observations of the angular dependence of ESR spectra of SeO2 radicals formed by X-ray irradiation of a single crystal of ferroelectric triglycine selenate were carried out. Two kinds of SeO2 radicals were produced due to the difference in manner of selenium-oxygen bond scission. In spite of the difference in stability of radicals in TGSe and those in TGS, the behavior of SeO2 radicals in the phase transition region is in line with that expected from the result of X-ray diffraction study of TGS.
  • Katsuki Kitahama, Hideko Kiriyama, Yoshihisa Baba
    1979 Volume 52 Issue 2 Pages 324-328
    Published: 1979
    Released: April 19, 2006
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    The title compound crystallizes in the trigonal space group R\bar3m with a=7.171, c=21.952 Å, and Z=3 at 298 K. The crystal structures at 298 and 120 K, as well as the lattice parameters in the temperature range 113–298 K, have been determined by X-rays, in order to elucidate the mechanism of the phase transition occurring at Tt=156 K. The structure of the high-temperature phase is essentially the same as that determined by Wyckoff, except for the discrimination between C and N atoms. No change in the space group nor in the basic structure was detected over the temperature range studied, in spite of a strong suggestion from previous 35Cl-NQR measurements. A small but significant anomaly associated with the transition is recognized in the c axis, which retains almost the same length near and below Tt. As a result, the lattice shrinkage below Tt becomes increasingly anisotropic as the temperature is lowered, whereas the thermal expansion above it is relatively isotropic.
  • Akira Kuboyama
    1979 Volume 52 Issue 2 Pages 329-333
    Published: 1979
    Released: April 19, 2006
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    The very broad absorption band of 1,4-dichloroanthraquinone, which corresponds to the allowed 1B2uπ,π* band of anthraquinone (AQ), is shown to consist of two π,π* bands with comparable intensities. The band which corresponds to the 1Ag forbidden band of AQ is at longer wavelengths than the band corresponding to the 1B2u band of AQ. MO calculations were made, and MCD spectra and 77 K absorption spectra were measured. The very broad absorption band of 1,4-dimethyl-AQ can probably be similarly interpreted. The strong visible π,π* bands of 1,4- and 1,5-disubstituted AQ’s are shown to arise from the 1Ag and 1B2u bands of AQ, respectively.
  • Toshikazu Takada, Kimio Ohno
    1979 Volume 52 Issue 2 Pages 334-338
    Published: 1979
    Released: April 19, 2006
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    Ab initio LCAO MO SCF and limited CI calculations are carried out on the electronic structure of the C3H3+ ion. Two kinds of basis sets are used, namely the minimal STO’s and the minimal STO’s plus 3d orbitals on each carbon atom. With the latter basis, the equilibrium C–C distance is calculated to be 1.389 Å. It is predicted that the C–C bond distance of C3H3+ is shorter than that of C6H6. The calculated C–C stretching force constant is 7.92 mdyn/Å and is close to the experimental value 6.59 mdyn/Å. Contour diagrams of the charge distribution of valence electrons are drawn and it is revealed that the calculated C–C bonds are bent and have two maxima in charge density. In terms of population analysis of localized MO’s, it is shown that the C–H bond in this molecule has a higher s-character than the C–H bonds in C2H4 and C6H6 and is close to an sp hybrid. This is in accord with a very large NMR coupling constant J13C–H. From CI calculations of low lying excited states, singlet σ-π* states (1A1″, 1E″, 1A2″) are calculated to be lower than the singlet π-π* state (1E′).
  • Yoshihiro Furukawa, Hideko Kiriyama
    1979 Volume 52 Issue 2 Pages 339-343
    Published: 1979
    Released: April 19, 2006
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    The proton and fluorine-19 spin-lattice relaxation times, T1 and T, in polycrystalline ammonium hydrogendifluoride were measured in the temperature range 142–345 K to elucidate the molecular motion of cation and anion. Below 200 K, the relaxation rates of both nuclei can be accounted for by dipolar interactions modulated via the isotropic reorientation of NH4+ ions. The logT versus 1/T curves above 200 K exhibit two distinct minima, suggesting that two crystallographically nonequivalent HF2 ions undergo 180°-flips about their two-fold axes with different correlation times. The activation energy of the NH4+ reorientation was determined to be 25.5±1.0 kJ/mol from the T1 data, while those of the 180°-flips were estimated from the T data to be about 40 and 60 kJ/mol for the two types of anions. These relaxation mechanisms have been confirmed by further experiments on a partially deuterated sample.
  • Hiroatsu Matsuura, Nobuyuki Miyauchi, Hiromu Murata, Masaaki Sakakibar ...
    1979 Volume 52 Issue 2 Pages 344-350
    Published: 1979
    Released: April 19, 2006
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    The Raman and infrared spectra of 2-chloro- and 2-bromoethyl methyl sulfides CH3SCH2CH2X (X=Cl and Br) were measured for the liquid and crystalline solid states. The vibrational frequencies of these molecules were calculated by the use of the force constants transferred from unbranched alkyl sulfides and alkyl halides. The rotational isomerism was studied on the basis of the spectral observations and the calculations, and the following conclusions were obtained. (1) In the crystalline solid state, both the chloride and the bromide take the molecular form with the gauche conformation about the (C)S–C(C) axis and the trans conformation about the (S)C–C(X) axis. (2) In addition to this form (GT), three other forms (TG, GG, and TT) coexist in the liquid state, the GT form being the most stable. (3) The sulfur atom is suggested to lower the energy of the trans conformation of the (S)C–C(X) axis.
  • Hiroyasu Inoue, Yukimi Hiroshima, Norio Makita
    1979 Volume 52 Issue 2 Pages 351-354
    Published: 1979
    Released: April 19, 2006
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    The photochemical reduction of benzo[c]cinnoline in strongly acidic 2-propanol (4 M HCl) has been studied using light of wavelength longer than 400 nm. The photoproduct has been identified as 5,6-dihydrobenzo[c]cinnoline. The quantum yields for product formation, which are the same as that for the disappearance of the reactant, have been measured under various conditions. In contrast to the poor phosphorescent property of benzo[c]cinnoline, the protonated species has been found to phosphoresce with significant efficiency. The lowest triplet state energy has been estimated to be 51 kcal/mol. The results of the quenching showed that the photoreduction was attributed to the lowest excited triplet state of protonated benzo[c]cinnoline. The pKa value in the reactive state is lower than that in the ground state.
  • Masaru Ohsaku, Norihisa Bingo, Wataru Sugikawa, Hiromu Murata
    1979 Volume 52 Issue 2 Pages 355-360
    Published: 1979
    Released: April 19, 2006
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    The CNDO/2 spd′ parametrizations of Kd, βc, ζs, and βs have been performed. Some of the valence and torsional angles of 1,2-ethanedithiol (CH2SH)2, 1,2-bis(methylthio)ethane (CH2SCH3)3, methanethiol, ethanethiol, (methylthio)methanethiol CH3SCH2SH, and bis(methylthio)methane CH3SCH2SCH3 have been optimized. In order to obtain further information on the rotational isomerism, CNDO/2 spd′ and sp calculations have been conducted for the molecules with variations in torsional angle.
  • Iwao Satake, Takeshi Gondo, Hideo Kimizuka
    1979 Volume 52 Issue 2 Pages 361-364
    Published: 1979
    Released: April 19, 2006
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    The cooperative binding of decylammonium chloride to poly(L-glutamic acid) (PLG) was studied by the potentiometric measurement of the binding isotherm at pH 7.9. Circular dichroism spectra were also measured as a function of the degree of binding of surfactant ion (x). It was shown that the coil to α-helix transition of PLG-surfactant complex takes place with a change in x. PLG did not undergo an appreciable conformational change in the range of x below 0.55. But the helical content increased suddenly with further increase in x. An abrupt increase in the helical content of PLG-surfactant complex can be well interpreted in terms of the hydrophobic interaction among bound surfactant ions. On the basis of the theoretical analysis of the cooperative binding isotherm, it was concluded that the formation of a micelle-like cluster consisting of at least eight surfactant ions is required for the stabilization of a surfactant induced helical structure.
  • Setsuo Kashino, Kuniaki Ito, Masao Haisa
    1979 Volume 52 Issue 2 Pages 365-369
    Published: 1979
    Released: April 19, 2006
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    The crystal structure of benzanilide has been determined from Weissenberg photographs using Cu Kα radiations and refined to an R value of 0.075 for 766 independent reflections. The crystals are monoclinic, space group C2/c, Z=4, with a=24.34(4), b=5.325(3), c=8.012(8) Å, β=107.2(3)°, Dm=1.32 and Dx=1.321 g cm−3. Dihedral angle between the benzene rings is 62.6°, and each benzene ring makes dihedral angle of 31.3 and 31.6° with the plane of amido group as found in Kevlar and Nomex polymers. The molecules related by a b-translation are linked together by N–H…O hydrogen bond [N…O 3.112(6), H…O 2.03 Å, N–H…O 157°] to form a chain along b. The chains are held together primarily by dipole forces of carbonyl groups of the molecules related by inversion centers to form a sheet parallel to the bc plane. The sheets are stacked along a with disorder by van der Waals interactions.
  • Akifumi Onodera, Tadayoshi Sakata, Hiroshi Tsubomura, Naoto Kawai
    1979 Volume 52 Issue 2 Pages 370-374
    Published: 1979
    Released: April 19, 2006
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    The electrical and chemical properties of some Würster’s salts have been studied under the static pressure of up to 250 kbar. In most cases the resistances of the salts decreased to the respective minima and then rose irreversively with increasing pressure. Spectral observations on the recovered specimens revealed that such behavior is associated with chemical reaction induced by the pressure. This reaction takes place more readily in the salts of p-phenylenediamine cation radical than in those of Würster’s red or Würster’s blue radicals.
  • Toshio Yoshioka
    1979 Volume 52 Issue 2 Pages 375-379
    Published: 1979
    Released: April 19, 2006
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    The static magnetic susceptibility and the low-field ESR spectra (33.6 and 135 MHz) of powder samples of tri-p-tolylaminiumyl chloroantimonate were measured above 1.7 K. A broad maximum in the susceptibility, which indicates an antiferromagnetic interaction, was observed at 6.0 K; this is consistent with the results of the proton NMR measurements. In the low-field ESR spectra, broadening of the g=2 absorption line and distinct appearance of the g=4 absorption line were observed in the temperature region below Tm, the temperature at which the susceptibility is maximum. The results are interpreted by assuming that the magnetic behavior is due to antiferromagnetic Heisenberg linear chains. An abrupt decrease in the g=2 absorption intensity and a rapid increase in the g=2 absorption linewidth were also found in the temperature range from 3.5 to 2.5 K, while a slight rise in the susceptibility was observed below 2.5 K. These anomalies may imply a magnetic-phase transition in the vicinity of 2.5 K.
  • Takashi Takahashi, Yoshiya Harada, Naoki Sato, Kazuhiko Seki, Hiroo In ...
    1979 Volume 52 Issue 2 Pages 380-382
    Published: 1979
    Released: April 19, 2006
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    The gas and solid phase UV photoelectron spectra of rubrene were measured. In the molecule there is little conjugation of π-electrons between four substituent phenyl groups and the naphthacene skeleton owing to the effect of the steric hindrance of the phenyl groups. Therefore, the lower IP bands in the gas phase spectrum could be correlated to the π-bands in the photoelectron spectra of benzene and naphthacene. The features of the solid phase spectrum are similar to those of the gas phase one except for a large peak due to inelastically scattered electrons. The polarization energy due to the molecular ion in the solid, the peak to peak difference between the gas and solid phase spectra, was observed to be 0.6 eV, which is about half the polarization energy for naphthacene. This means that rubrene molecules are loosely packed in the solid as a result of the steric hindrance of four phenyl groups.
  • Yoshiaki Hamada, Masamichi Tsuboi
    1979 Volume 52 Issue 2 Pages 383-385
    Published: 1979
    Released: April 19, 2006
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    Fourier transformed infrared absorption spectrum of gaseous ClO2 has been obtained with the resolution of 0.06 cm−1. The rotational structure of the bending fundamental band (v2=1←0) was analyzed. Rotational constants determined were in good agreement with previous microwave results. The band center was now fixed at 447.675±0.030 cm−1, and five centrifugal distortion constants for the v2=1 state were also newly determined.
  • Kunihito Koumoto, Takao Matsubara, Masasuke Takata, Hiroaki Yanagida
    1979 Volume 52 Issue 2 Pages 386-389
    Published: 1979
    Released: April 19, 2006
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    The interdiffusion coefficients \ ildeD of Zn2+ ions in aluminium cobalt(II) oxide (cobalt aluminate) and aluminium nickel(II) oxide (nickel aluminate) were measured. In the former \ ildeD is independent of the concentration of the composition-dependent cation vacancies, while in the latter it decreases with increase in the concentration of cation vacancies. The difference in the distribution of cations and cation vacancies in the spinel lattice has a great effect on the interdiffusion coefficients of Zn2+ ions. The results were interpreted by means of the vacancy mechanism for Co2+ and Ni2+ ions and the interstitial or interstitialcy mechanism for Zn2+ ions. The activation energy is independent of the concentration of Zn2+ ions or cation vacancies; 355 kJ mol−1 for cobalt aluminate and 364 kJ mol−1 for nickel aluminate.
  • Masahiro Harada, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1979 Volume 52 Issue 2 Pages 390-394
    Published: 1979
    Released: April 19, 2006
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    X-Ray crystal structure analysis of [PtCl2{(t-Bu)2P(CH2)3P(t-Bu)2}]·0.5C6H5Cl has been carried out. Crystals belong to monoclinic system: a=11.532(2), b=14.984(5), c=16.455(4) Å, β=106.96(2)°, space group P21/c with Z=4. The structure, solved by the heavy-atom method, has been refined anisotropically by least-squares procedure to R=0.056 for 5019 non-zero reflections. The coordination around the platinum atom is approximately square-planar, however, it showed a slight deviation toward the tetrahedral geometry; Pt–P=2.281(3) and 2.282(3), Pt–Cl=2.359(3) and 2.362(3) Å, P–Pt–P=99.05(9) and Cl–Pt–Cl=83.18(11)°.
  • Yoshio Kinsho, Natsuo Onodera, Minoru Sakiyama, Syûzô Seki
    1979 Volume 52 Issue 2 Pages 395-402
    Published: 1979
    Released: April 19, 2006
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    Heat capacities of KSCN and NH4SCN crystals were measured by adiabatic calorimetry in the temperature range between 13 K and the melting points. Molar volume of NH4SCN was also determined above room temperature. Entropy change for the II-I transition of KSCN (414.54 K, essentially higher order but accompanied with the first order component) is 6.26 J K−1 mol−1 (=1.09 R In 2), which is of similar magnitude with our previous value (Bull. Chem. Soc. Jpn., 36, 1025 (1963)). Entropy change for the III-II transition of NH4SCN (360.1 K,first order) is 10.01 J K−1 mol−1 and apparent entropy change for the II-I transition of NH4SCN (392.8 K, higher order) is 2.85 J K−1 mol−1 (=0.49 R In 2) in spite of possibly similar nature of the transition with the II-I transition of KSCN. A possibility has been suggested that the entropy change might be approximately R In 2 if the transition was not interfered with the III-II trasition and the premelting.
  • Masao Sekizaki
    1979 Volume 52 Issue 2 Pages 403-406
    Published: 1979
    Released: April 19, 2006
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    The crystal structure of tris(L-asparaginato)cobalt(III) trihydrate, [Co(L-H2NCOCH2CHNH2COO)3]·3H2O, has been determined by the X-ray diffraction method, and refined by a block-diagonal least-squares method to give R=0.055 for 1302 non-zero reflections. The crystals are orthorhombic with a space group P212121, a=39.082(4), b=7.523(2), c=6.643(2) Å, and Z=4. The complex molecule has a slightly distorted octahedral coordination with fac(N)-Δ geometry. The three bidentate ligand ions form five-membered planar chelate rings with coordination through amino nitrogen and carboxyl oxygen atoms. The amide groups of the two side-chains approach the central atom, and the oxygen atoms are connected through intramolecular hydrogen bonds. Another amide group is, however, far from the central atom. The complex molecules are hydrogen-bonded to one another to form layers parallel to the (100) plane. These layers are piled up through hydrogen bonds to complete a threedimensional network.
  • Takashi Isago, Kozo Igi, Jinsai Hidaka
    1979 Volume 52 Issue 2 Pages 407-414
    Published: 1979
    Released: April 19, 2006
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    Four kinds of [Co(N)2(O)3(S)] type mixed complexes, (L- or D-aspartato)(L-methioninato), and (L- or D-aspartato) (S-methyl-L-cysteinato)cobalt(III) complexes have been prepared and chromatographically separated into their three geometrical isomers, trans(N), trans(SO) and trans(SN), respectively. The isomers were identified from their electronic absorption and PMR spectra. The absolute configurations of sulfur atoms in the ligands after coordination were suggested on the basis of their PMR spectra. The circular dichroism spectra of the isomers were considered in relation to their geometrical configurations.
  • Toshio Yamaguchi, Hitoshi Ohtaki
    1979 Volume 52 Issue 2 Pages 415-419
    Published: 1979
    Released: April 19, 2006
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    From X-ray scattering measurements on ammoniacal aqueous solutions of copper(II) chloride at the NH3/Cu mole ratios of 4.8 and 5.0, four ammonia molecules at the equatorial position and other two water molecules at the axial one were found to be coordinated to a copper(II) ion at the distance of 2.03 and 2.33 Å, respectively. The radial distribution curve obtained for an aqueous solution of copper(II) chloride saturated with ammonia (NH3/Cu=11.2) showed that a higher ammine copper(II) complex than the tetraamminecopper(II) ion is formed in the solution. The complex has a distorted octahedral form in which the equatorial Cu–N bond distance is 1.93 Å. The axial apices of the octahedron at the distance of 2.30 Å are occupied by either an ammonia molecule and a water molecule or two ammonia molecules. The present study shows that the structures of the tetra- and higher-ammine copper(II) complexes in solution are different from those in crystal.
  • Kohzo Sugiyama, Kunio Watanabe, Seiji Motojima, Yasutaka Takahashi
    1979 Volume 52 Issue 2 Pages 420-424
    Published: 1979
    Released: April 19, 2006
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    Single crystals of zirconium nitride (ZrN) have been grown by the modified filament-method from a gas mixture of ZrCl4, N2, H2, and Ar. The cubic crystals grew at 2000–2200 °C with a gas flow ratio 2N2/ZrCl4 of 2–6, and evaporation of ZrN took place above 2400 °C. Linear growth rates along the <100> direction have been measured in terms of sequential micrographs, and attained a maximum of 60–75 μm/min at 2100–2200 °C. The atomic ratio N/Zr of grown crystals increased with an increase of the flow ratio 2N2/ZrCl4, and reached a constant of 0.93 above the flow ratio of 3.
  • Toshiro Ono, Haruo Miyata, Kyoji Tôei
    1979 Volume 52 Issue 2 Pages 425-427
    Published: 1979
    Released: April 19, 2006
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    A colloid titration method for the determination of sodium dodecylbenzenesulfonate (LAS) with poly(4-vinyl-1-pentylpyridinium bromide) (polysoap) is described. The end-point detection is based on the measurement of turbidity, the transmittance at 420 nm or 680 nm being used for the determination. The most successful results were obtained by titrating LAS (1–7.5×10−4 N) with 2.5×10−3 N polysoap solution. The purity of commercial LAS was found to be 81–84%.
  • Hisanobu Wakita, Setsuko Kinoshita
    1979 Volume 52 Issue 2 Pages 428-432
    Published: 1979
    Released: April 19, 2006
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    The solid solutions in the systems La2(CO3)3·8H2O–Ce2(CO3)3·8H2O and La(OH)CO3–Ce(OH)CO3 have been synthesized by the hydrolysis of the lanthanum–cerium trichloroacetates. The X-ray diffraction data of the solid solutions of La2(CO3)3·8H2O–Ce2(CO3)3·8H2O indicated a lanthanite-type structure while the data of La(OH)CO3–Ce(OH)CO3 indicated a bastnaesite-type structure. The correlations between lanthanite, bastnaesite, and calkinsite, and the lanthanite-bastnaesite transformation are discussed.
  • Toshishige M. Suzuki
    1979 Volume 52 Issue 2 Pages 433-436
    Published: 1979
    Released: April 19, 2006
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    The optical resolution of [Co(dmpy)3]3+, [Co(en)(dmbpy)2]3+, [Co(en)(bpy)2]3+, and [Rh (dmbpy)3]3+(dmbpy=3,3′-dimethyl-2,2′-bipyridine) has been achieved using (−)D tris(L-cysteinsulfinato)cobaltate(III). The dmbpy complexes consist of a pair of stereo-selective enantiomers. The absorption and CD spectra of two series of complexes, [Co(en)x(dmbpy)3−x]3+ and [Co(en)x(bpy)3−x]3+ (x=0, 1, 2, 3) and also [Rh(dmbpy)3]3+ have been investigated. The complexes containing more than two aromatic ligands showed an exciton CD in the ligand π-π* transition region and the band has been related to the absolute configuration of the complexes. The spectral features of dmbpy Complexes are different from those of the bpy complexes and such differences have been discussed with reference to the twisting nature of dmbpy chelates.
  • Ryosho Kuwae, Toshio Tanaka, Katsuhiko Kawakami
    1979 Volume 52 Issue 2 Pages 437-440
    Published: 1979
    Released: April 19, 2006
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    The reaction of Rh(dtc)L2 (dtc=S2CN(CH3)2, L=2,4,6-(CH3)3C6H2NC) with an equimolar amount of iodine yields a trans adduct, RhI2(dtc)L2. The rate of this reaction was measured in benzene, employing a stopped flow technique under pseudo-first-order conditions with excess iodine. The result indicates that the reaction proceeds via a charge transfer complex Rh(dtc)L2·I2, which is rearranged in two consecutive zero-order reactions with respect to the I2 concentration; the rearrangement of Rh(dtc)L2·I2 to a cis adduct followed by isomerization to the trans adduct. This mechanism is supported from kinetic data for the reaction of Rh(acac)L2 (acac=CH3COCHCOCH3) with I2. It is also described that RhI(I3)(dtc)L2 and RhI(I3)(acac)L2 were obtained by reactions of Rh(dtc)L2 and Rh(acac)L2 with excess iodine, respectively.
  • Katsura Mochizuki, Tasuku Ito, Masatoshi Fujimoto
    1979 Volume 52 Issue 2 Pages 441-445
    Published: 1979
    Released: April 19, 2006
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    The 1H NMR spectra of PAR, [CoIII(par)2], and [CoIII(par)(dien)]+ were measured in D2O solutions. The signals were assigned. The deuteration of H7 was observed in D2O solutions of free ligand PAR around pD 9–10, where PAR exists in the form of LH having an intramolecular hydrogen-bond. The significant up-field shift for the resonance of H1 was observed in [CoIII(par)2] but not in [CoIII(par)(dien)]+. The shift was interpreted in terms of the magnetic anisotropy due to the π-electron system of the neighboring PAR molecule in the complex. The down-field shift for the resonance of the H5 signal of the cobalt(III) complexes reflects the structural change of PAR upon chelate-ring formation. PAR coordinates to cobalt(III) ion in planar terdentate fashion, viz., in a mer configuration.
  • Kazunori Teramoto, Yoichi Sasaki, Kouto Migita, Masamoto Iwaizumi, Kaz ...
    1979 Volume 52 Issue 2 Pages 446-451
    Published: 1979
    Released: April 19, 2006
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    The dimeric molybdenum(II) complex, Mo2(CF3COO)4, forms Mo2(CF3COO)4·(CH3CN)2 in acetonitrile, where solvent molecules are attached to positions trans to the metal–metal bond (apical positions). The rate of ligand exchange between Mo2(CF3COO)4 ((1.31–8.28)×10−2 M; M=mol dm−3) and CF3COONa ((1.31–4.56)×10−1 M) was measured in acetonitrile by the use of 19F NMR spectroscopy. The rate is independent of the total concentration of CF3COONa and is linearly dependent on that of Mo2(CF3COO)4. The first-order rate constant (kex) is (1.1±0.2)×104 s−1 (25 °C), and the activation parameters are ΔH\ eweq=(8.2±0.8) kcal mol−1 and ΔS\ eweq=(−15±3) K−1 mol−1. Under the given conditions the complex seems to exist as Mo2(CF3COO)4·CF3COO, where the underlined ligand occupies one of the apical positions, and the following mechanism is proposed (solvent molecules are omitted; asterisks indicate the molecule substituting for the coordinated ligand).
    Mo2(CF3COO)4·CF3COO+*CF3COO\oversetfast\ ightleftarrowsMo2(CF3COO)4·*CF3COO+CF3COO
    Mo2(CF3COO)4·*CF3COO\oversetks→Mo2(CF3COO)3(*CF3COO)·CF3COO
    The kex corresponds to ks.
  • Shun’ichiro Ooi, Masato Nishizawa, Keiji Matsumoto, Hisao Kuroya ...
    1979 Volume 52 Issue 2 Pages 452-457
    Published: 1979
    Released: April 19, 2006
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    A new complex, aquaoxo[N-(2-pyridylmethyl)iminodiacetato]vanadium(IV) dihydrate [VO(pmida)(H2O)]·2H2O has been synthesized and its crystal structure determined by the X-ray method. The triclinic crystals obtained from water or aqueous ethanol solution are twinned and contain 2 mol of lattice water. The unit cell contains four formula units and the structure was analyzed on the assumption that the space group is P\bar1. The positional and thermal parameters were refined to R=0.115. The vanadium atom has a distorted octahedral coordination and deviates by 0.39 Å from the equatorial plane, which is composed of two cis carboxylate oxygens, a water molecule and the pyridine nitrogen. Vanadyl oxygen and tertiary nitrogen occupy the axial sites. Absorption spectra indicated that the structure is maintained in an aqueous solution of pH 3.0 to 4.9. This geometrical isomer seems to be formed selectively in an aqueous medium.
  • Kenzo Kitayama, Tadashi Sugihara, Takashi Katsura
    1979 Volume 52 Issue 2 Pages 458-461
    Published: 1979
    Released: April 19, 2006
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    The phase equilibria in the Er2O3–V2O3–V2O5 system have been established at 1200 °C. In this system, Er2O3, Er8V2O17(4Er2O3·V2O5), ErVO3, ErVO4, VnO2n−1(n: 2 to 7), and VO2 found to be stable, Er8V2O17, ErVO4, V2O3, and VO2 of which had non-stoichiometric compositions. On the basis of the phase equilibria, the standard Gibbs energies for the reactions,
    ErVO3+1⁄2O2=ErVO4, (1)
    3Er2O3+2ErVO3+O2=Er8V2O17, (2)
    have been determined to be −121±1 and −256±1 kJ, respectively. It has been shown that the standard Gibbs energy for Sm, Er, and Lu in Eq. 1 decreases linearly with increasing ionic radius of lanthanoid.
  • Munehiro Nakatani, Tsunao Hase
    1979 Volume 52 Issue 2 Pages 462-465
    Published: 1979
    Released: April 19, 2006
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    In the reaction with tosyl chloride in pyridine, the meso isomer (2a) of bis[2-hydroxy-1-(2,6-dimethyl-4-methoxyphenyl)ethyl] ether rearranged to give arylacetaldehyde (3) and 2-arylmethyl-4-aryl-1,3-dioxolane (4), and the racemic isomer (2b) afforded 3, 4, and 2,6-diaryl-1,4-dioxane. The aryl migration in this reaction has been confirmed by the use of the deuterated compounds, 2a-D and 2b-D, respectively, substituted with deuteriums at the 2,2-positions.
  • Mitsuji Yamashita, Tadaaki Miyano, Takashi Watabe, Hiromi Inokawa, Hir ...
    1979 Volume 52 Issue 2 Pages 466-468
    Published: 1979
    Released: April 19, 2006
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    Reaction of dimethyl phosphonate with phenylketene dimethyl dithioacetal derivatives have been investigated to prepare s-alkylphosphonates. The addition reactions of phosphonate were accelerated in dithioacetal derivatives in the following order: –SMe<–SOMe<<–SO2Me. The reaction of β,β-bis(methylsulfonyl)styrene (7) with dimethyl phosphonate followed by the catalytic reduction afforded dimethyl α-methylbenzylphosphonate in 74% yield from compound 7. The reaction of 1-methylsulfinyl-1-methylthio-4-phenyl-1-butene with dimethyl phosphonate gave dimethyl (2-methylthio-1-phenethylvinyl) phosphonate in 21% yield.
  • Hiroo Inoue, Tadashi Nagata, Hiroyuki Hata, Eiji Imoto
    1979 Volume 52 Issue 2 Pages 469-473
    Published: 1979
    Released: April 19, 2006
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    Iron polyphthalocyanine (Fe-poly PC) has been found to act as an electron-transfer reagent in the reductions of α-substituted ketones, α-bromodeoxybenzoin (1a), 2-bromopropiophenone (1b), α,α-bis(phenylthio)deoxybenzoin (4), and 1,2-diketones, benzil (5) and 4,5-octanedione (8), with benzenethiol. The α-bromo ketones (1a and 1b) have been debrominated to their parent ketones. 4 has been reduced to α-(phenylthio)deoxybenzoin and deoxybenzoin via the cleavage of the carbon-sulfur bond, and 5 and 8 to the corresponding α-hydroxy ketones. The ability of Fe-poly PC to perform these reactions is superior to that of iron phthalocyanine (Fe-PC), particularly those reactions in dry benzene. The catalytic action of Fe-poly PC and Fe-PC becomes evident when methanol or 80 vol % aqueous methanol is used as solvent. Furthermore, the reductions of related compounds by the Fe-poly PC-benzenethiol system are described.
  • Teruaki Yamada, Yoshio Kamiya
    1979 Volume 52 Issue 2 Pages 474-478
    Published: 1979
    Released: April 19, 2006
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    The ligand effects of 2,2′-bipyridine, ethylenediamine, and diethylenetriamine on the rate of decomposition of 1,2,3,4-tetrahydro-1-naphthyl hydroperoxide catalyzed by cobalt(II) decanoate and copper(II) decanoate in chlorobenzene were kinetically studied. The results were compared with the redox potentials measured in nonaqueous media and the spectral data of cobalt(II) and copper(II) complexes. It was found that the catalytic activity of Me(II) decanoate–ethylenediamine, or -diethylenetriamine complex (Me=Co, Cu) becomes maximum at 1/2 the molar ratio of ethylenediamine to Me(II), or at 1/3 that of diethylenetriamine to Me(II), and that further addition of these amines deactivates the catalysts. The activity of copper(II) decanoate increased from k=0 to k=1.4×10−3 s−1 on addition of 2,2′-bipyridine when the molar ratio of 2,2′–bipyridine to copper(II) decanoate was 0–4. No maximum activity was observed in copper(II) decanoate-2,2′-bipyridine system. A large excess of 2,2′-bipyridine, 150 times the quantity of copper(II) salt, did not decrease the decomposition rate in contrast to the case of the cobalt(II) decanoate–2,2′-bipyridine system. The difference in ligand effect of ethylenediamine, diethylenetriamine and 2,2′-bipyridine on cobalt(II) ion and copper(II) ion was discussed on the basis of the properties of these complexes.
  • Tsutomu Mizoroki, Toshio Matsumoto, Atsumu Ozaki
    1979 Volume 52 Issue 2 Pages 479-482
    Published: 1979
    Released: April 19, 2006
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    The effect of iodide ion was examined in methanol carbonylation with use of Co-, Rh-, and Ir-catalysts. Sodium iodide gives no noticeable effect on carbonylation catalyzed by Rh-catalyst to give acetic acid, and retards that catalyzed by Ir-catalyst. Methyl iodide is effective for methanol carbonylation with Co-catalyst in the presence of hydrogen to give mainly acetaldehyde, which is readily hydrogenated to ethanol during the course of carbonylation on addition of a catalytic amount of Ru3(CO)12. Sodium iodide is also effective for acetaldehyde formation, although it strongly retards the hydrogenation of acetaldehyde with Ru-catalyst. The different effect of iodide ion on methanol carbonylation catalyzed by Co-, Rh-, or Ir-catalyst is discussed in terms of neucleophilicity of the active catalyst species.
  • Suketaka Ito, Akikazu Kakehi, Yumo Tanaka, Kazuyoshi Yoshida, Toshiyuk ...
    1979 Volume 52 Issue 2 Pages 483-487
    Published: 1979
    Released: April 19, 2006
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    Thermolysis of the title dihydrotetrazine in boiling toluene gives benzenesulfonic anhydride, S-phenyl benzenethiosulfonate, and small amounts of diphenyl disulfide and a rearrangement product, 3,6-diphenyl-1,2-bis(phenylsulfonyl)-1,2-dihydro-1,2,4,5-tetrazine, together with 3,6-diphenyl-1,2,4,5-tetrazine. On the other hand, the treatment with concentrated sulfuric acid affords 3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine in good yield. On the basis of the kinetic parameters obtained for the thermolysis, the mechanism was discussed.
  • Kazuhito Nakamura, Yukari Morita, Toru Suzuki, Toru Sugiyama, Akira Su ...
    1979 Volume 52 Issue 2 Pages 488-491
    Published: 1979
    Released: April 19, 2006
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    The main reactions of pyridinecarboxylic esters induced by Co-60 γ-rays in acidic alcoholic solutions are: 1) substitution on the pyridine ring by alkyl or hydroxyalkyl groups derived from solvent alcohols, and 2) reduction of carboxylic esters to alcohol (hydroxymethyl group). Substitution is dominant in methanol solutions and reduction is dominant in 2-propanol solutions. Carboxylic esters at the 2- and 4-positions are selectively reduced to alcohols. Alkylation results from the attack by hydrogen atoms and hydroxylalkyl radicals. Reduction of carboxylic esters to alcohol is effected by the hydroxyalkyl radicals derived from the radiolysis of alcohols.
  • Tadashi Yao, Yoshio Kamiya
    1979 Volume 52 Issue 2 Pages 492-495
    Published: 1979
    Released: April 19, 2006
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    In order to elucidate the reaction mechanism of coal dissolution in the hydrogen-donating solvent, twenty aromatic compounds related to coal were treated at 450 °C in the presence of tetralin. Diphenylmethane and bibenzyl slowly decomposed giving alkylbenzenes almost quantitatively. Diphenylmethanol and benzophenone were hydrogenated to diphenylmethane, and benzyl phenyl ketone to a mixture of diphenylmethane and bibenzyl. Diphenyl ether and dibenzofuran are very stable, di-2-naphthyl ether decomposing slowly and benzyl phenyl ether or dibenzyl ether very rapidly. The conversion of aromatic compounds by thermolysis can be correlated as a function of bond dissociation energy. The bond rupture of coal-related polynuclear aromatic compounds at 450 °C was concluded to occur mainly at methylene or ether structures. Addition of phenolic compounds or quinoline is very effective for the decomposition of di-2-naphthyl ether. The effect of phenolic compounds and quinoline on the thermal decomposition of aromatic ether was discussed on the basis of stabilization of transition state due to solvation.
  • Renji Okazaki, Kazuhiko Sunagawa, Kyung-Tae Kang, Naoki Inamoto
    1979 Volume 52 Issue 2 Pages 496-501
    Published: 1979
    Released: April 19, 2006
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    Photoreactions of 1,2-benzodithiole-3-thione with olefins (cyclopentene, cyclohexene, cyclooctene, and 2,3-dimethyl-2-butene) afforded deep blue o-thioquinonemethides (4) in high yields. The thione 4 is equilibrated with a colorless head-to-head dimer having an eight-membered ring. The mode of the dimerization has been discussed in comparison with other o-quinonoid compounds. Cycloaddition reactions of 4 with electron-deficient acetylenes and olefins gave rise to [4+2] adducts. It was confirmed that these cycloadditions proceeded stereoselectively as well as regioselectively. Reactions of 4 with diphenylketene, phenyl isocyanate, and phenyl isothiocyanate led to six-membered 1 : 1 adducts. Reduction by hydride reagents has been also described.
  • Mitsuo Masaki, Satoshi Matsunami, Takayuki Kimura, Tokio Oshima
    1979 Volume 52 Issue 2 Pages 502-506
    Published: 1979
    Released: April 19, 2006
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    Although bis[2(1H)-pyridinethionato]zinc (1) is prepared by the reaction of 2(1H)-pyridinethione with zinc chloride in the presence of stoichiometric amount of sodium hydroxide, a similar reaction in the presence of a large excess amount of the base gave μ4-oxo-hexakis-μ-[2(1H)-pyridinethionato-(N,S)]-tetrazinc (2) which is the first example of L6Zn4O (L=ligand) type complexes having heterocyclic thiolato groups as ligands. The complex 2 was also prepared by several routes, which involve hydrolysis of 1 and the reaction of 1 with zinc oxide. In these complexes 2(1H)-pyridinethionato ligand acts as a bidentate or bridging ligand. Attempts to convert bis(4,6-dimethyl-2-pyridylthio)zinc or bis(1-oxido-2-pyridylthio)zinc into a complex of L6Zn4O type were failed. Complexes of L6Zn4O type were also prepared when L were 2-thiazolidinethionato, 5-methyl-2-thiazolidinethionato, and 1-methyl-4-imidazoline-2-thionato.
  • Teiji Chihara, Kazunori Tanaka
    1979 Volume 52 Issue 2 Pages 507-511
    Published: 1979
    Released: April 19, 2006
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    Cyclohexanone (1) and one of its 2-alkyl (methyl, ethyl, or propyl) derivatives (2) were hydrogenated competitively at 30 °C in cyclohexane over platinum group metals. The alkyl derivatives 2 were all less reactive than 1 on all the catalysts used. The relative reactivity R2R1 was given by log10(R2R1)=σ**+k, with σ** depending only upon the substituent and k upon the catalyst. The greater the substituent size, the more negative was the substituent constant σ**. The catalyst-dependent constant K was in general more negative for a catalyst metal having a smaller atomic radius. The above empirical rate expression has been interpreted based on the absolute reaction rate theory. The σ** values calculated on this theoretical ground were in excellent agreement with the observed values.
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