Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 55 , Issue 6
Showing 1-50 articles out of 70 articles from the selected issue
  • Yoshiharu Nakano, Shoichi Sato
    1982 Volume 55 Issue 6 Pages 1683-1687
    Published: 1982
    Released: June 27, 2006
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    The crystal structure and the absolute configuration of (−)589-3-(2,4-dinitro-1-naphthyl)-2,4-pentanedionato[tris(2-aminoethyl)amine]cobalt(III) dibromide were determined by X-ray diffraction. The complex crystallizes as the orthorhombic space group P212121, with a=13.738(2), b=15.446(1), c=12.243(1) Å, and Z=4. The structure was solved by the Patterson-Fourier method and refined to a final R1 value of 0.038 for the 3347 observed reflections with |Fo|>3σ(|Fo|). The acetylacetonate (acac) ring adopts a more deformed boat conformation than that in 3-(6-methyl-2,4-dinitrophenyl)-2,4-pentanedionato analogue. The three chelate rings of tris(2-aminoethyl)amine (tren) have envelope conformations and adopt λ, λ, and δ conformations. The absolute configuration of the title compound can be designated as R.
  • Shousuke Teratani, Junichi Nakamichi, Kazuo Taya, Kazunori Tanaka
    1982 Volume 55 Issue 6 Pages 1688-1690
    Published: 1982
    Released: June 27, 2006
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    A series of TiO2 catalysts loaded with transition metals were prepared by photodeposition. The activity order for these catalysts in the title reaction was as follows: Pt/TiO2>Rh/TiO2>Pd/TiO2>Ru/TiO2>Ir/TiO2>TiO2. Upon heat treatment the activities of all the metal/TiO2 catalysts were enhanced, but the above sequence was unaltered.
  • Tomoyoshi Setoi, Motomich Inoue, Daiyu Nakamura
    1982 Volume 55 Issue 6 Pages 1691-1694
    Published: 1982
    Released: June 27, 2006
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    The Co(II) and triplet exciton ESR spectra of Co(II)-doped [TMPD+]2[Ni(mnt)2] and [TMPD+]2[Pt(mnt)2] were observed at different temperatures. The triplet exciton signals of the solid solutions yielded practically the same ESR parameters as those of the pure Ni(II) and Pt(II) complexes. The Co(II) spectra showed a wellresolved hyperfine structure, each component line of which became broad with increasing temperature. This can be interpreted in terms of exciton transfer from TMPD+ lattices to the metal ions.
  • Kazuhiko Suga, Minoru Kinoshita
    1982 Volume 55 Issue 6 Pages 1695-1704
    Published: 1982
    Released: June 27, 2006
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    The static and dynamic properties of the phosphorescent triplet states of quinoxaline and 2,3-disubstituted derivatives in hexane have been studied at 1.4 K using the methods of optically detected magnetic resonance. In addition, the absorption and phosphorescence excitation spectra have also been measured to attain the information about the low lying excited states. A systematic comparison has been made for the purpose of examining the effect of substitution. A significant enhancement of the pumping rates for the y spin sublevel observed in the chlorinesubstituted derivatives is concluded to be due to the additional indirect process of intersystem crossing which occurs from S1 of n,π* to T1 passing through the intermediate triplet state of π,π*. A detailed discussion on the observed phosphorescence spectra originating from the three sublevels has achieved a satisfactory success in understanding the mechanisms responsible for the radiative decay processes. It is concluded that the mechanisms due to vibronic coupling with closely lying n,π* triplet states are of little importance in the systems studies here.
  • Shoji Noda, Kiyoshi Sanehira, Takahisa Doba, Hiroshi Yoshida
    1982 Volume 55 Issue 6 Pages 1705-1709
    Published: 1982
    Released: June 27, 2006
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    ESR measurements during photolysis of duroquinone (DQ) solutions in ethanol and 2-propanol have revealed the generation of both durosemiquinone anion (DQ) and durosemiquinone radicals (DQH·). Correspondingly, alkoxyl radicals have been detected from the photolyzed solutions by the spin trapping-ESR technique, though the quantum yield of their formation is very low (10−3 for the ethanol solution). Main conclusions deduced from the present work are (1) that DQ\ ewdot is generated through the one-electron reduction of DQ by α-hydroxyalkyl radical and through the photodissociation of (DQ-DQH2) complex, and (2) that DQH· is generated through the hydrogen abstraction of 3DQ* either from solvent alcohols or from photoproduct durohydroquinone (DQH2). The one-electron reduction in alcohol solution previously reported for p-benzoquinone is a minor pathway of chemical quenching of 3DQ*. The quantum yield of the DQH2 formation in an early period of photolysis of a dilute DQ in methanol, ethanol, and 2-propanol has been observed to be 0.12, 0.23, and 0.36 respectively. These values are discussed in terms of the mechanism of the quinone photorecduction.
  • Kotaro Araya, Yoshio Matsunaga
    1982 Volume 55 Issue 6 Pages 1710-1714
    Published: 1982
    Released: June 27, 2006
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    The induction of liquid crystals was demonstrated with binary mixtures comprising N-(4-nitrobenzylidene)-4-nitroaniline and N-[4-(dimethylamino)benzylidene]-4-alkoxyaniline or N-(4-alkoxybenzylidene)-4-(dimethylamino)aniline. Both nematic and smectic phases were observed with the ethoxy derivatives, but only a smectic A phase with the propoxy derivatives. The mesophases appear in the region centered around 30 mol% of the dinitro compound. Similarly, liquid crystals could be induced in several mixtures of N-[4-(dialkylamino)benzylidene]-4-(dialkylamino)aniline with N-(4-nitrobenzylidene)-4-alkoxyaniline or N-(4-alkoxybenzylidene)-4-nitroaniline. The bis(dialkylamino) and dinitro derivatives of azoxybenzene were also shown to be efficient as one of the component compounds in producing binary liquid crystals.
  • Yoshihisa Fujii, Michio Kashiwagi, Hideki Nakada, Yukio Kurita
    1982 Volume 55 Issue 6 Pages 1715-1718
    Published: 1982
    Released: June 27, 2006
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    ESR studies of X-irradiated single crystals of dicyclohexyldiazene 1,2-dioxide, (C6H12NO)2, revealed the generation of the stably trapped radicals C6H11N(O)N′H″(O′)C6H11. The principal elements of the g value were found to be 2.0030, 2.0060, and 2.0086. The principal elements of the hyperfine coupling constants were found to be 3.88, 1.53, and 1.38 mT for N, and 1.53, 1.41, and 1.14 mT for H″. The direction cosines of these principal elements, when compared with those of the bonds in the parent molecule, indicate that the radical is formed by addition of a hydrogen atom to the N=N′ double bond without causing a large change in the molecular framework. The spin densities for this radical were calculated to be 0.041 and 0.47 in the 2s and 2p orbitals of the atom N, respectively.
  • Yukio Kosaki, Akira Miyamoto, Yuichi Murakami
    1982 Volume 55 Issue 6 Pages 1719-1726
    Published: 1982
    Released: June 27, 2006
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    By using a three-way catalyst containing a metal oxide, NO can be selectively converted to N2 and N2O without the formation of NH3 even at the “rich” side of the air/fuel ratio. In order to elucidate the mechanism of this action of the added metal oxide, the NO–H2 reaction on Pt–V2O5/Al2O3 catalyst was investigated using the pulse reaction technique. In the NO–H2 reaction on Pt/Al2O3 catalyst, a significant amount of NH3 was formed in the “rich” region of the reactants (H2/NO>1), although NO was completely removed. In the NO–H2 reaction on the Pt–V2O5/Al2O3 catalyst, on the other hand, no NH3 was formed even in the “rich” region of the reactants; in addition, NO was completely removed. During the NO–H2 reaction on the Pt–V2O5/Al2O3 catalyst, the V2O5 in the catalyst was found to be reduced from V5+ to V4+. The reaction of NO with NH3 and the reaction of NH3 or H2 with Pt–V2O5 mixed catalysts for various states of mixing were also investigated. From these results, the NO–H2 reaction on the Pt–V2O5/Al2O3 catalyst has been shown to be composed of the following three main steps: Step I, the formation of NH3 by the reduction of NO with H2 on Pt; Step II, the NO–NH3 reaction on Pt to form N2 or N2O; and Step III, the reduction of V2O5 in the catalyst by H2 which is accelerated by the “hydrogen spil-lover.” In the NO–H2 reaction on Pt/Al2O3 catalyst, NO is first reduced to NH3 in Step I and the NO–NH3 reaction in Step II follows. In the “rich” region, the formation of NH3 takes place more readily than the subsequent NO–NH3 reaction. In the NO–H2 reaction on the Pt–V2O5/Al2O3 catalyst, the formation of excess NH3 is suppressed by the removal of hydrogen from Pt in Step III, and the NH3 thus produced reacts with NO to form N2 or N2O selectively in Step II. The rates of Steps I, II, and III were also discussed in terms of the structure of the catalysts and composition of the reactants.
  • Koichiro Matsuda, Kiwamu Yamaoka
    1982 Volume 55 Issue 6 Pages 1727-1733
    Published: 1982
    Released: June 27, 2006
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    Electric birefringence (EB) and electric linear dichroism (ED) of a sonicated DNA (Mw=1.24×105) sample were studied in solutions containing various additives at 7 °C. Signals of EB at 535 nm and of ED at 260 nm were measured in the electric field range 0–ca. 19 kV/cm. Both signals obeyed the Kerr law at low field strengths (E<ca. 5 kV/cm) and showed a saturating trend at high fields. The mean relaxation time, <τ>EB, obtained from the decay of EB, was field-strength dependent, indicating the effect of the polydispersity of sDNA. The field strength dependence of steady-state EB signals was nearly identical with that of ED signals. These results were analyzed with the “classical” orientation functions derived for mono- and polydisperse systems. The optical anisotropy factor (g3g1) of sDNA was ca. −2.0×10−2, while the average angle between the orientation axis of sDNA and the transition moment of the base pair was ca. 70° at 260 nm. The electric moment of sDNA was influenced by ionic strength, counterions, and other additives. The weight-average length lw of sDNA decreased in this order: 0.2 mM NaCl**>9-aminoacridinium chloride (PD=10)>1.0 mM NaCl>0.33 mM MgCl2> 20 vol% glycerol. Values of lw/base pair were 2.8−2.7 Å in the glycerol and 3.6−3.4 Å in the 1.0 mM NaCl.
  • Tsunetoshi Kobayashi, Hiroshi Suzuki, Keiichiro Ogawa
    1982 Volume 55 Issue 6 Pages 1734-1738
    Published: 1982
    Released: June 27, 2006
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    Conformations of (Z)-stilbene, (E)-stilbene, and various methyl-substituted (E)-stilbenes were discussed from the standpoint of photoelectron spectroscopy. Photoelectron spectral data of (Z)-stilbene and (E)-stilbene were found to be perfectly consistent with the results by the gas electron diffraction method concerning the twist angles of the phenyl groups. The twist angles of the phenyl groups in various methyl-substituted (E)-stilbenes were estimated using the photoelectron spectral data by the new method presented recently. These estimated values correspond well to those obtained from the standpoint absorption spectra.
  • Jun-ich Hamada, Shigeru Tsunashima, Shin Sato
    1982 Volume 55 Issue 6 Pages 1739-1743
    Published: 1982
    Released: June 27, 2006
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    Hydrogen azide was photolyzed in liquid cyclopropane at the temperature of Dry Ice–methanol. The main products observed were nitrogen, cyclopropylamine, and ammonia. The relative yields of the products depended slightly on the concentration of hydrogen azide. The results were then compared with those obtained with paraffin and olefin. The isobutane solution of hydrogen azide was photolyzed at 0 °C. The products observed were the same as those obtained at the temperature of Dry Ice-methanol. The relative yields of the products and the concentration dependence, however, were different.
  • Kozue Kaibara, Hideo Kimizuka
    1982 Volume 55 Issue 6 Pages 1743-1747
    Published: 1982
    Released: June 27, 2006
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    This paper is concerned with analysis of membrane transport processes on the basis of nonequilibrium thermodynamics. Inter-ionic correlations between permeating ions are quantitatively estimated by applying the membrane permeability matrix theory to the system in which the NaCl and CsCl solution phases are divided by a highly selective cation exchange membrane. The membrane permeability matrix of the system may be expressed by four ionic correlation terms concerning with Na+ and Cs+. The electroconductive and diffusional membrane permeabilities are expressed as a function of the matrix elements having the dimension of permeating speed of ions. The conductive and diffusional permeabilities as well as the matrix elements are estimated from membrane potential, conductance, and ionic flux data. The external electrolyte concentration dependence of these permeability parameters is discussed. The conductive and diffusional permeabilities considerably differ from each other and their ratio changes with the external electrolyte concentration, whereas the permeability ratio of Na+ to Cs+ is constant. Electroconductive and diffusional characteristics of membrane transport processes are consistently analyzed in terms of the memberane permeability matrix theory.
  • Takehiko Ono, Yutaka Kubokawa
    1982 Volume 55 Issue 6 Pages 1748-1752
    Published: 1982
    Released: June 27, 2006
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    The rate of oxidation of C3H6 has been investigated over V–Mo oxides using 18O2(99%) tracer. The extent of participation of lattice oxygen in the oxidation increases with increasing MoO3 content, showing a maximum at V–Mo (33 mol% of MoO3) oxide. The rate of oxidation of C3H6 varies parallel to the extent of participation of lattice oxygen. A marked dependence of the rate of oxidation upon oxygen pressure observed with V–Mo(33) oxide is attributed to its high reducibility. Similar experiments have been carried out with V–Sn (94 mol% of SnO2) oxide. The rate of reduction of the oxide with C3H6 is about ten times smaller than that of the corresponding catalytic oxidation of C3H6, suggesting the participation of adsorbed oxygen in the oxidation. The results of 18O tracer experiments show participation of lattice oxygen in the oxidation. A mechanism which explains such conflicting results has been proposed.
  • Takahisa Doba, Hiroshi Yoshida
    1982 Volume 55 Issue 6 Pages 1753-1755
    Published: 1982
    Released: June 27, 2006
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    In order to give a quantitative basis for the spin trapping technique, the spin trapping rate constants for the reactions between commonly-used spin traps and cyclohexyl radicals have been determined. The cyclohexyl radicals were generated by γ-irradiating cyclohexane solutions of the spin traps. The rate constants for nitrosobenzene, nitrosodurene, pentamethylnitrosobenzene, 2,4,6-tri-t-butylnitrosobenzene, and α-phenyl-N-t-butylnitrone at 299 K are 9×107, 1.4×107, 1.6×107, 2.4×104, and 8×103 mol−1 dm3 s−1, respectively. The results are qualitatively in accordance with previous data for t-butyl, 1-methyl-5-hexenyl radicals.
  • Takashi Tamaki
    1982 Volume 55 Issue 6 Pages 1756-1760
    Published: 1982
    Released: June 27, 2006
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    The fluorescence quantum yields and lifetimes of 1- and 2-acetyl- or benzoylanthracenes were measured in various degassed solvents at room temperature. The natural fluorescence lifetime was evaluated to be 30–40 ns, depending a little on the compounds, but little on the solvent. This strongly supports the recent finding that the lowest excited singlet state of the acylanthracenes is of a ππ* character. On the basis of triplet-yield measurements, it was also confirmed that the low fluorescence yield in nonpolar solvents is due to an efficient intersystem crossing to an upper triplet state.
  • Takashi Tamaki
    1982 Volume 55 Issue 6 Pages 1761-1767
    Published: 1982
    Released: June 27, 2006
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    The effect of small amounts of methanol (≤0.34 mol dm−3) upon the absorption and fluorescence spectra of 1- and 2-acetylanthracenes in hexane was investigated. While the formation of a 1 : 1 hydrogen-bonded complex in the ground state was revealed by the isosbestic points of the absorption spectra, the change in the fluorescence spectra was indicative of the photogeneration of a highly associated complex which includes at least two alcohol molecules. On the assumption that the excited 1 : 1 complex further associates with an alcohol molecule, the computer simulation by the least-squares method provided a good fit of the observed concentration dependence of methanol upon the fluorescence quantum yield. The photokinetic parameters and the thermodynamic quantities were evaluated from the parameter values.
  • Kiyoshi Otsuka, Takao Yasui, Akira Morikawa
    1982 Volume 55 Issue 6 Pages 1768-1771
    Published: 1982
    Released: June 27, 2006
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    The reduction of In2O3 by H2 or CO and the reoxidation of the reduced oxide by water, accompanying the formation of hydrogen, have been investigated at ≥673 K. The reduction of In2O3 and the decomposition of water have been expressed by the forward reaction and the backward reaction respectively of this equation: In2O3(s)+xH2(g)\ ightleftarrowsIn2O3−x(s)+xH2(g), where In2O3−x(s) is a mixture of indium metal and In2O3. Surface oxygen atoms of fresh In2O3 are easily removed by H2- or CO-reduction at 673 K, but they can not be reformed by oxidation with water. This explains the observation that the quantity of hydrogen produced in the oxidation step was somewhat deficient compared to that consumed by the reduction. The maximum rate of the decomposition of water is observed when the oxide has been reduced up to a 50% reduction-level. However, an excessive reduction (greater than 85%) results in a sharp decrease in the rate of the decomposition of water, probably because of the isolation of metallic indium from the host In2O3.
  • Toshihisa Yoshida, Yataro Ushiki
    1982 Volume 55 Issue 6 Pages 1772-1776
    Published: 1982
    Released: June 27, 2006
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    The bromate-cerium(III) and -iron(II) reactions in acidic media were examined with special reference to their induction periods and reaction rates. In the bromate-cerium(III) reaction, the induction period is followed by a burst of cerium(IV) formation and then a gradual formation of cerium(IV). In the bromate-iron(II) reaction, a slow decrease occurs only in acidic media, even without bromate, so it may differ from the decrease in the tris(1,10-phenanthroline)iron(II) concentration based on the oxidation by bromate. It was interpreted as the dissociation from [Fe(phen)3]2+ to [Fe(phen)2]2+ and phen. This is the induction period for iron(III) formation, which follows as the burst. The induction period and the rates of cerium(IV) or iron(III) formation can be interpreted on the basis of the mechanism for the Belousov oscillatory and the present redox reactions proposed by Noyes and his co-workers.
  • Hironobu Kunieda, K\={o}z\={o} Shinoda
    1982 Volume 55 Issue 6 Pages 1777-1781
    Published: 1982
    Released: June 27, 2006
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    A three-phase region consisting of surfactant (D), water (W), and oil (O) phases appeared due to the superposition of two critical phenomena of D–W and O–D in a nonionic surfactant/water/oil system. Three interfacial tensions, γO–W, γO–D and γD–W, among the three phases were determined at various temperatures. The generalized Antonoff’s rule (γO–WO–DD–W) holds approximately in the three-phase region. γO–D and γD–W disappear at the respective critical solution temperatures, and ultralow interfacial tensions are attained in the vicinity of both critical temperatures. The oil–water interfacial tension, γO–W, reaches its minimum in the midst of the temperature range of the three-phase region, and the narrower the temperature range of the three-phase region, the lower the interfacial tension. The correlation between the interfacial tensions and the types of emulsions is also discussed.
  • Hiroaki Ohya-Nishiguchi, Atsushi Terahara, Noboru Hirota, Yoshiteru Sa ...
    1982 Volume 55 Issue 6 Pages 1782-1789
    Published: 1982
    Released: June 27, 2006
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    The spin density distributions and the energy stabilizations in the polymer cation radicals (Rn) have been investigated by measuring the oxidation potentials (E1⁄2°) and the electron spin resonance (ESR) spectra of the cation radicals generated by the electrochemical oxidations of some multilayered compounds. E1⁄2° decreased monotonically as the number of layers increased. The spin densities on the aromatic rings have been estimated from the hyperfine coupling constants with the help of the McLachlan’s and INDO calculation. It was found that the spin density tends to localize in the central moieties in Rnn. The localization of the spin density and the energy stabilization are interpreted with a simple theoretical model of Rnn, which takes into accounts the repulsion integral (γ1) and resonance integral (ζ) between the nearest neighbor molecules. The comparison with the experimental data has lead to the numerical estimates of γ1=0.1 eV and ζ=0.4 eV.
  • Teiichiro Ogawa, Fumihiro Miyoshi, Morihide Higo
    1982 Volume 55 Issue 6 Pages 1790-1794
    Published: 1982
    Released: June 27, 2006
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    Dissociative excitation of CHCl3 and CDCl3 has been investigated by means of the controlled electron impact and the high resolution emission spectroscopy. The emission spectrum shows such excited species as H, CH, CH+, Cl+, CCl, and HCl+. The excitation function of H* has two thresholds, 20.5 and 41.0 eV. The emission cross spections of H* and D* reveal an isotope effect, which is dependent on the excitation energy and the principal quantum number. Translational energy distributions of H* and D* have been determined from the Doppler line shape of the Balmer-β line, and average translational energies from the half-width of the Balmer-α, β, γ, and δ lines. There are no noticeable isotope effect for the translational energy; their major peaks lie at 0–1, 4, and 6–12 eV. These findings indicate that there are at least three major processes for the formation of the excited hydrogen atom. They are assigned to dissociative excitation through the Rydberg states converging to the (2a1)1 ionic states and through excited Rydberg states.
  • Hiroki Nakamura, Jiro Tanaka, Nobuaki Nakashima, Keitaro Yoshihara
    1982 Volume 55 Issue 6 Pages 1795-1797
    Published: 1982
    Released: June 27, 2006
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    The photoionization mechanism of 1-anilinonaphthalene (1-AN) was investigated by a nanosecond laser flash photolysis and the result was compared with that of 8-anilino-1-naphthalenesulfonate (ANS). The photoionization of 1-AN in polar solvent is shown to occur through a biphotonic process via a triplet state; the mechanism is different from those of ANS, in which an intermediate of a charge transfer to solvent (CTTS) state was observed. Thus the major deactivation process of the lowest excited singlet state is an intersystem crossing in 1-AN, while it is a transition to the CTTS state in ANS which might be stabilized by the sulfonato group.
  • Masatoshi Hirayama, Yoshimichi Kawamata, Yuki Fujii, Yoshiharu Nakano
    1982 Volume 55 Issue 6 Pages 1798-1802
    Published: 1982
    Released: June 27, 2006
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    Ln(fod)3 (Ln=La, Pr, Nd, Sm, and Eu)-induced 59Co shifts (δCo) for a series of tris(β-diketonato)Co(III) complexes were determined directly from separate observations of the free complexes and 1 : 1 adducts with Ln(fod)3 at room temperature (25 °C) in CHCl3; Ln(dpm)3-induced shifts were also observed in CCl4. Values of δCo corrected for the adduct-formation shifts (δ′Co) are separated into contact and pseudo-contact contributions by using the intercept and slope in a linear plot of δ′Co⁄<Sz> vs. D⁄<Sz>. It is suggested from the estimated hfs constant of 59Co (≈−0.2 G, 10−4T) that the spin polarization mechanism may be predominant for the electron spin transfer from Ln ion into Co ion.
  • Masatoshi Hirayama, Mitsuo Kaneko
    1982 Volume 55 Issue 6 Pages 1803-1805
    Published: 1982
    Released: June 27, 2006
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    NMR spectra were observed for green solutions formed from dimethyl, diethyl, and diisopropyl terephthalates in contact with sodium metal in THF-d8 in vacua at ambient probe temperature. A comparison of proton chemical shifts with excess charge densities calculated by the CNDO MO method supports that the green species are disodium salts of π-dianions.
  • Masanao Kato
    1982 Volume 55 Issue 6 Pages 1806-1810
    Published: 1982
    Released: June 27, 2006
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    The estimation of the liquid-liquid distribution coefficients of acetylacetone tautomers was attempted on the basis of the UNIFAC equation, and it was found that the calculated values of the reciprocals of the activity coefficients of tautomers in organic phases were linearly related to the distribution coefficients. It was verified that the estimation by the UNIFAC equation could be extended to the organic solvents with no characteristic parameter.
  • Akira Nakashima, Toshiyuki Isobe, Toshikazu Tarutani
    1982 Volume 55 Issue 6 Pages 1811-1819
    Published: 1982
    Released: June 27, 2006
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    Coordination behaviors of VO(II), Cr(III), Mn(II), Fe(III), Cu(II), and Gd(III) ions for the iminodiacetato group in the chelating ion-exchange resin Dowex A-1 were studied with the aid of ESR, infrared absorption, and M\ddotossbauer spectroscopies. A comparative investigation also was made with the o-hydroxybenzyliminodiacetato group in the chelating resin Unicellex UR-50. The iminodiacetato group in Dowex A-1 is considered to coordinate as a tridentate ligand and form 1 : 1 chelates with metal ions, whereas the o-hydroxybenzyliminodiacetato group in Unicellex UR-50 coordinates as a quadridentate ligand in alkaline media and forms 1 : 1 chelates. Elucidation of spin-spin exchange interaction has led to a conclusion that the iminodiacetato groups present in the coordination pore of Unicellex UR-50 are closer to one another than those of Dowex A-1. For Fe(III) ions adsorbed in concentrated HCl media, besides the species [FeCl4], lower symmetric species are considered to be adsorbed with the anion exchange effect, from results of resin phase ESR and Mössbauer spectra.
  • Kenzo Kitayama, Takashi Katsura
    1982 Volume 55 Issue 6 Pages 1820-1823
    Published: 1982
    Released: June 27, 2006
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    The phase equilibria in the Gd2O3–V2O3–V2O5 system are studied at 1200 °C by changing the oxygen partial pressure from −0.68(air) to −12.50 in terms of logPO2. In this system, Gd2O3, GdVO4, GdVO3, 0.81Gd2O3. 0.19V2O5, V2O3, V3O5, V4O7, V5O9, V6O11, V7O13, and VO2 are stable. GdVO4 and 0.81Gd2O3·0.19V2O5 have nonstoichiometric compositions. The crystallographic properties of the latter are determined with reference to the indices of a certain compound, 4Tm2O3·V2O5. On the basis of the phase equilibria, the Gibbs free energy of these two reactions: 31/50 Gd2O3+19⁄50 GdVO3+19⁄100 O2= Gd1.62V0.38O3.38 and: GdVO3+1⁄2 O2= GdVO4 are determined to be 57.0 and 127.8 kJ respectively.
  • Takeo Adachi
    1982 Volume 55 Issue 6 Pages 1824-1830
    Published: 1982
    Released: June 27, 2006
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    The properties of HF–H3BO3 media and the distribution coefficients of eighteen metals have been investigated to achieve the separation of hard acid-metals by the anion exchange method. As the addition of boric acid to hydrofluoric acid solution reduces the free fluoride ion concentration to about one hundredth, it is possible to control the formation of metal fluoride complexes in a way favorable for the separation. The BF4 and BF3OH produced in this media are adsorbed strongly to the resin and reduce the relative adsorbabilities of metal fluoride complexes remarkably. Using these properties of HF–H3BO3 media and the adsorbabilities of other anions, a new anion exchange method for the separation of hard acid-metals has been proposed. The new method is especially useful for the separation of titanium, zirconium, niobium, and tantalum. Distribution coefficients and elution behaviors of metal ions are not affected by the increase of the amount of metals because of the buffer action relating to the fluoride in HF–H3BO3 media.
  • Takao Yagi, Kayoko Kojima, Hiroyuki Nariai, Itaru Motooka
    1982 Volume 55 Issue 6 Pages 1831-1833
    Published: 1982
    Released: June 27, 2006
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    The analytical procedure for the separation and quantification of various phosphorus oxoacids was investigated by the capillary type isotachophoresis. The various phosphorus oxoacids, such as linear-, cyclic-, and lower phosphorus oxoacids, were separated at pH 5.5 with a 0.01 mol dm−3 hydrochloric acid–histidine–0.1% triton X-100 mixture as the leading electrolyte and a 0.01 mol dm−3 hexanoic acid as the terminating electrolyte. The PU value increased in the order of P3m<P4m<P3<P2<\overset1P<\overset3P<P1. The calibration curves for the various phosphorus oxoacids were linear in the range of 0.5–3.5 μg as phosphorus oxoacids. Coefficients of variation for the measured phosphorus oxoacids were less than 2% except for P3. Separation times were approximately 15 min. This procedure was applied to the ground phoshates.
  • Yoshihiko Kushi, Toshiji Tada, Yuki Fujii, Hayami Yoneda
    1982 Volume 55 Issue 6 Pages 1834-1839
    Published: 1982
    Released: June 27, 2006
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    The crystal and molecular structure of the title complex (−)435-ΛRS2(mer)-[Co(α-Me-sal2en)(N-Bz-L-ala)]·3H2O, has been determined by single crystal X-ray analysis. The crystals are orthorhombic, space group P212121, with unit cell dimensions a=19.247(8), b=14.162(4), c=10.329(4) Å, and Z=4. The structure was solved by the heavy-atom method and refined by block-diagonal least-squares technique, using 1624 independent reflections, to the final R-value of 0.080. The molecular structure is of a ΛRS-cis2(mer) type in which two coordination sites of a distorted octahedron are occupied by the N-Bz-L-ala group and the others by the quadridentate α-Mesal2en Schiff-base ligand in a nonplanar configuration. The Co–O and Co–N bon lengths, 1.938(12) and 1.989(15) Å respectively, of the N-Bz-L-ala group are significantly longer than the usual values. The molecule is distinctly strained as shown by the bond angles of the ligands and those of the cobalt(III) coordination polyhedron. The water molecules form a hydrogen bonded chain linking phenolate and carboxylate oxygens of different molecules along the crystallographic c axis.
  • Keiji Matsumoto, Shun’ichiro Ooi, Hiroshi Kawaguchi, Mamoru Naka ...
    1982 Volume 55 Issue 6 Pages 1840-1844
    Published: 1982
    Released: June 27, 2006
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    The crystal structures of (−)589-[Cr(NCS)2(tn)2]1/2[Sb2(+)-tart2]·2H2O (1) and (−)589-[Co(NCS)2(tn)2]1/2-[Sb2(+)-tart2]·2H2O (2) have been determined from the X-ray diffraction data. The structures were solved by the Patterson-Fourier method and refined by the least-squares method to R=0.043 (1) and 0.070 (2) for 2659 and 1826 reflections respectively. The two crystals are isomorphous with each other. The complex cations in 1 and 2 have a similar geometry. Their absolute configuration is Λ, and agrees with that assigned from the CD spectra in comparison with those in the first d-d band region of bis(ethylenediamine)cobalt(III) complexes. The six-membered chelate rings are of chair conformation. The chairs are flattened more than expected from the conformational analysis.
  • Kazuo Muraishi, Kenzo Nagase, Masae Kikuchi, Kozo Sone, Nobuyuki Tanak ...
    1982 Volume 55 Issue 6 Pages 1845-1849
    Published: 1982
    Released: June 27, 2006
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    The thermal dehydration reactions of lanthanoid(III) malonate hydrates Ln2mal3·nH2O (Ln=Ce–Lu; mal=CH2(COO)2; n=6 for Ce–Eu and 8 for Gd–Lu) were investigated mainly by the thermogravimetries under conventional conditions and in atmosphere of water vapor at a constant reduced pressure and a superslow heating rate. The latter conditions were useful especially to detect the formation of new intermediate hydrates, and to determine the dehydration temperatures with accuracy. The main features of the results could be reasonably understood in view of the effects of the lanthanoid contraction.
  • Toshio Nakamura, Yasuke Yumoto, Kosuke Izutsu
    1982 Volume 55 Issue 6 Pages 1850-1853
    Published: 1982
    Released: June 27, 2006
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    Formation constants of the 1 : 1 complexes of lithium ion in acetonitrile (AN) with DMF, DMSO, DMA, and HMPA and of sodium ion in AN with 15-crown-5 (15C5), 18-crown-6 (18C6), dibenzo-18-crown-6 (DB18C6), and cryptand 211 (Cryp 211), were determined at 10, 25, and 40 °C by potentiometric methods with a cationsensitive glass electrode. From the change of the formation constants with temperature, thermodynamic parameters ΔG298°, ΔH298° and −TΔS298°, were obtained. ΔG298°, ΔH298°, and −TΔS298° all in kJ mol−1, for Li+-solvent complexes were, respectively, −7.9, −9·0, +1·1 for DMF, −9.7, −10·1, +0·5 for DMSO, −10.0, −9·9, −0·1 for DMA, and −18.9, −15·8, −3·1 for HMPA, and those for Na+-macrocyclic polyether complexes, −28.4, −24·1, −4·5 for 15C5, −27.2, +1·6, −28·7 for 18C6, −28.6, −14·3, −14·2 for DB18C6, and −51.9, −53·8, +2·1 for Cryp 211. Some features about the roles of enthalpy and entropy terms in complexing have been discussed.
  • Tadashi Hara, Motohiro Toriyama, Masakatsu Imaki
    1982 Volume 55 Issue 6 Pages 1854-1857
    Published: 1982
    Released: June 27, 2006
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    The D-glucose concentration in a serum sample of less than 0.01 cm3 could be continuously determined at the rate of about 20 samples/h by the use of a chemiluminescent reaction between luminol and hydrogen peroxide, a flow-cell with immobilized peroxidase, and a column with immobilized glucose oxidase. By immobilizing peroxidase as a chemiluminescent catalyst inside the flow-cell, simplification could be achieved with regard to apparatus, reagents and operation. The detection limit of hydrogen peroxide was about 5×10−6 mol dm−3, and the calibration curves for both hydrogen peroxide and D-glucose were approximately linear in the range of 5×10−5–1×10−3 mol dm−3, a range which corresponded to the glucose concentration, 0.1–18 mg cm−3, obtained by diluting serum to 50 times its initial volume.
  • Ryokichi Tsuchiya, Akira Uehara, Yoshiyuki Ohtsuka
    1982 Volume 55 Issue 6 Pages 1858-1861
    Published: 1982
    Released: June 27, 2006
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    The enthalpy changes (ΔH) in the reaction of Ni(AA)2X2·nH2O type complexes with aqueous potassium cyanide were calorimetrically measured at 25 °C, where AA is N,N′-diethylethylenediamine (NN′-deen) or N,N-diethylethylenediamine (NN-deen); X is Cl, Br, I, or NO3 ion; and n is 0 or 2. On the basis of the enthalpy data measured, the thermal stability was compared among chloride, bromide, iodide, and nitrate in the following each group of compounds: Ni(NN′-deen)2X2·2H2O, Ni(NN′-deen)2X2, Ni(NN-deen)2X2·2H2O, and Ni(NN-deen)2X2. The thermal stability was found to decrease in the order, chloride>bromide>nitrate>iodide in each group. Comparison of the enthalpy data between the chlorides of the NN′-deen and NN-deen complexes revealed the difficulty of anation in the latter rather than in the former. [Ni(NN-deen)2(H2O)2]Br2 was, when heated, converted into [Ni(NN-deen)2]Br2 without anation differing from the chloride. The difference was also discussed on the basis of the enthalpy data.
  • Ushio Sakaguchi, Hiroshi Nakazawa, Kazuhisa Sakai, Hayami Yoneda
    1982 Volume 55 Issue 6 Pages 1862-1868
    Published: 1982
    Released: June 27, 2006
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    The circular dichroism spectra of some cis-bis(ethylenediamine)cobalt(III) complexes have been measured in several solvents. Among these complexes, the diisothiocyanato complex was found to exhibit a marked solvent dependence; the dominant circular dichroism band in the lowest energy spin-allowed transition region changed its sign upon going from, e.g., water, dimethyl sulfoxide, methanol, or acetone to pyridine or its analogues. Coupled with the proton NMR spectra and a similar solvent dependence of the circular dichroism spectra of nitroisothiocyanatobis(ethylenediamine)cobalt(III) and diisothiocyanatobis(ethylenediamine)chromium(III) complexes, we ascribed the origin of the sign inversion of the diisothiocyanato complex to the stereoselective hydrogen bonding of cis N–HB with pyridine-like molecules, where cis N–HB is the hydrogen bonded to the nitrogen atom cis to NCS and directed off the molecular twofold axis.
  • Suketaka Ito, Akikazu Kakehi
    1982 Volume 55 Issue 6 Pages 1869-1873
    Published: 1982
    Released: June 27, 2006
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    A new concept, “Orbital Tilting,” leading to hybridization change, was introduced on the basis of the destabilizing and the stabilizing secondary orbital interaction. The predominant π-MO extension of norbornene in the exo-direction was elucidated by application of the concept to the orbital system.
  • Haruo Inoue, Kiyoshi Kawabe, Noboru Kitamura, Mitsuhiko Hida
    1982 Volume 55 Issue 6 Pages 1874-1879
    Published: 1982
    Released: June 27, 2006
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    The photoreduction of 2-piperidinoanthraquinone (1) by an electron transfer from hydroxide ion in aqueous 2-propanol was reinvestigated. The reaction proceeded actively on irradiation at 365 nm, but very weakly on irradiation at 420 nm. The fluorescence of 1 was not affected by hydroxide ion. 1,3-Cyclohexadiene as a triplet quencher retarded the photoreduction. All results revealed that the reactive state of 1 in the photoreduction is not the intramolecular excited CT state, but the upper excited nπ* triplet state. Kinetic studies indicated that the rate of deactivation from the T2(3*) level of 1 is unusually slow (kd=1.7×108 s−1). The photoreduction via the upper excited T2(3*) level was also observed in 1-amino- and 1-piperidinoanthraquinone, while 2-aminoanthraquinone did not exhibit any reactivity. Wavelength-dependencies (313 nm, 365 nm, and >420 nm irradiations) of the photoreductions were also observed.
  • Haruo Inoue, Mitsuhiko Hida
    1982 Volume 55 Issue 6 Pages 1880-1885
    Published: 1982
    Released: June 27, 2006
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    Photochemical electron transport from hydroxide ion to organic acceptor molecule via an anthraquinone derivative as an electron carrier was investigated in homogeneous, cationic micellar, and cationic reversed micellar systems. In homogeneous alkaline aqueous ethanol, the photochemically generated radical anion of sodium anthraquinone-2-sulfonate (1) was stable against further irradiation with visible light (λ>450 nm), while the dianion of 1 was reversibly converted to the radical anion by visible light irradiation. The reversible conversion was accelerated by the addition of an organic acceptor molecule such as 1,4-dicyanobenzene. In a cationic hexa-decyltrimethylammonium micellar system, an effective photoreduction of 1 by an electron transfer from hydroxide ion concentrated on the micellar surface to the excited 1 located in the surface area of the micelle was observed. In a reversed micellar system an electron was effectively transported from the water layer to the organic layer; an electron was transfered from hydroxide ion in the water layer incorporated in a benzylhexadecyldimethylammonium reversed micelle to 1 at the micellar surface by irradiation with light of λ=365 nm. Successive visible light irradiation (λ>450 nm) caused an electron ejection from the radical anion of 1 to benzonitrile as a bulk phase solvent. The possibility of the incorporation of carbon dioxide into the acceptor cycle of the electron transport system was also examined. In pyridine solution, carbon dioxide caused the disappearance of the reduced species of 1 on visible light irradiation (λ>450 nm). Trace amounts of dihydropyridinedicarboxylic acid derivatives were obtained.
  • Masako Yamamoto, Takayuki Sano, Tatsuya Yasunaga
    1982 Volume 55 Issue 6 Pages 1886-1889
    Published: 1982
    Released: June 27, 2006
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    The interaction of amylose with iodine was investigated as a function of degree of polymerization (DP) of amylose by amperometric titration, and the binding isotherms were obtained. The intrinsic equilibrium constant and cooperative parameter were determined with a one-dimensional Ising model for amyloses of various DPs. The inflection of the plot of the intrinsic equilibrium constant vs. DP observed at about DP 60 suggests that a helical segment of amylose consists of anhydroglucose residues less than 60. The discontinuity of the cooperativity at about DP 60 was interpreted by two kinds of cooperative effects, intra- and interhelical effects. These results suggest that the interrupted helix is a good model for the amylose structure in aqueous solution. The temperature dependencies of the cooperative parameters show that the cooperativity of amylose-iodine complexation is entropycontrolled.
  • Eishun Tsuchida, Hiroyuki Nishide, Yoshinori Sato, Manabu Kaneda
    1982 Volume 55 Issue 6 Pages 1890-1895
    Published: 1982
    Released: June 27, 2006
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    Iron(II)protoporphyrin IX N-[5-(2-methyl-1-imidazolyl)pentyl]amide ethyl ester (1) and its derivatives (2–4) were prepared. They predominantly form pentacoordinate heme complexes in organic and aqueous solutions, based on their 2-methylimidazole-ligand and spacer N-pentylamide groups. Oxygen adducts of 1–4 were rapidly formed on exposure to oxygen in N,N-dimethylformamide (DMF) at −30 °C, and their life-times were more than 30 min.
  • Yukihisa Fujita, Yasuchika Iwasa, Yukinao Noda
    1982 Volume 55 Issue 6 Pages 1896-1900
    Published: 1982
    Released: June 27, 2006
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    The thermal denaturation of lysozyme in aqueous solutions of polyhydric alcohols at pH 2 was investigated by differential scanning calorimetry (DSC). The polyhydric alcohols employed were inositol, sorbitol, xylitol, erythritol, glycerol, and ethylene glycol. These alcohols tended to enhance the thermal stability of lysozyme; both the temperature and the enthalpy of denaturation increased almost linearly with increasing alcohol concentration. The increase in denaturation temperature at a given alcohol concentration was a linearly increasing function of the number of hydroxyl groups per alcohol molecule. The denaturation enthalpy at identical temperature increased only slightly by the addition of polyhydric alcohol. The hypothesis may be supported that the dominant mechanism by which polyhydric alcohols stabilize proteins to thermal denaturation is through their effect on the water structure, which determines the strength of the hydrophobic interactions between the nonpolar groups of the protein.
  • Akira Kasahara, Taeko Izumi, Yoshio Yoshida, Iwao Shimizu
    1982 Volume 55 Issue 6 Pages 1901-1906
    Published: 1982
    Released: June 27, 2006
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    [3.3](1,3)Ferrocenophane-1,15-diene-3,14-dione was synthesized via the base-catalyzed condensation of 1,3-ferrocenedicarbaldehyde with 1,3-diacetylferrocene utilizing the high dilution technique. The reduction of the compound with LiAlH4–AlCl3 and the subsequent catalytic hydrogenation led to the formation of [3.3](1,3)ferrocenophane. The transannular π-electronic interactions between the two ferrocene moieties in these compounds were examined on the basis of NMR and electronic spectra.
  • Osamu Takazawa, Hiroshi Tamura, Kunio Kogami, Kazuo Hayashi
    1982 Volume 55 Issue 6 Pages 1907-1911
    Published: 1982
    Released: June 27, 2006
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    The Lewis acid-catalysed reaction of 1-trimethylsiloxy-1,3-cyclohexadienes with aldehydes and trialkyl orthoformates afforded the corresponding 4-substituted 2-cyclohexenones. A new reaction of 2,4,6-trienones with m-chloroperbenzoic acid followed by the reduction with zinc in acetic acid gave 7-hydroxy-3,5-dienones. Utilizing these efficient reactions, megastigma-4,6,8-trien-3-ones, 3-hydroxy-β-ionol, 3-hydroxy-β-ionone, 5,6-epoxy-3-hydroxy-β-ionol, and 3-oxo-α-ionol were successfully synthesized.
  • Hiroshi Yamamoto, Wolfgang Pfleiderer
    1982 Volume 55 Issue 6 Pages 1912-1914
    Published: 1982
    Released: June 27, 2006
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    The previous structures presented for the Hg(OAc)2 oxidation product of creatine, the condensation product of methylguanidine and diethyl oxalate, and the peracid oxidation product of 1-methyl-2-amino-dihydropyrimidines are all replaced by a revised formulation, 2-methylamino-1H-imidazole-4,5-dione on the basis of the pKa values (0.62 and 7.87) and the spectra. The equilibria between this thermodynamically controlled product and the previous formulations are discussed.
  • Yoshihito Watanabe, Tatsuo Numata, Shigeru Oae
    1982 Volume 55 Issue 6 Pages 1915-1920
    Published: 1982
    Released: June 27, 2006
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    In the oxygenation reaction of alkyl sulfides with Co(II)(bzacen)–O2 system, oxidative S–C bond cleavage (S-dealkylation) was found to take place exclusively. The reactivity of S-dealkylation reaction was dependent markedly on both acidity of α-methylene and steric hindrance of alkyl sulfide. The peroxo-Co(III) species is presumed to be the intermediate in this S-dealkylation reaction.
  • Shiro Kobayashi, Michihisa Isobe, Takeo Saegusa
    1982 Volume 55 Issue 6 Pages 1921-1925
    Published: 1982
    Released: June 27, 2006
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    Acyclic and cyclic (SAn and GAn) carboxylic anhydrides were added at room temperature to the C=N bond of unsubstituted cyclic imidates of 2-oxazoline (OZO) and 5,6-dihydro-4H-1,3-oxazine (OZI) to give addition products quantitatively. In contrast to these findings, the reactions of acetyl halides with OZO and OZI yielded ringopened products and the reactions of carboxylic anhydrides with 2-benzyl-2-oxazoline (BzOZO) afforded also the ring-opened products. The bicyclic addition product of OZO with SAn is equilibrated with a mixture of starting materials. The stereochemistry of addition products having a six-membered ring system is discussed.
  • Tohru Tsuchiya, Kazuhiro Ikehira, Juichi Imamura
    1982 Volume 55 Issue 6 Pages 1926-1930
    Published: 1982
    Released: June 27, 2006
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    The oxidation of phenol with peracetic acid has been investigated in connection with the industrial preparation of benzenediols. The effects of 25 additives, such as derivatives of monomeric and condensed phosphoric acid, chelating agents, and salts of polybasic carboxylic acids, were examined; derivatives of condensed phosphoric acid were found to be most effective. The oxidation of phenol (213 mmol) with peracetic acid (21 mmol) in the absence of the additives gave 1,2- and 1,4-benzenediols in only 5.8% and 7.6% yields, respectively. But in the presence of 2.0×10−7 mol of potassium diphosphate the yields of 1,2- and 1,4-benzenediol were 47% and 31%, respectively. The improvement in the yields by the additives is attributable to the masking of a trace of metals, especially iron and cobalt, present in the reaction mixture. These metals tend to catalyze the further oxidation of the benzenediols formed.
  • Jinya Koshitani, Toshio Kado, Yoshio Ueno, Takatoshi Yoshida
    1982 Volume 55 Issue 6 Pages 1931-1933
    Published: 1982
    Released: June 27, 2006
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    A kinetic study was performed on the oxidation of anthracene by use of copper(II) chlorocomplexes, which were produced in reactions of copper(II) acetate with lithium chloride in acetic acid. When the pressure of oxygen was high enough that the rate of oxidation was not affected, the result was as follows:
    −\fracdO2dt∝[RH]1[Cu2(OAc)4]01⁄2[LiCl]01⁄2−0.
    Akineticapproximationtotheexperimentalresultwasattempted.
  • Hisashi Tsuchida, Eiichi Narita, Hitoshi Takeuchi, Masahiro Adachi, Ta ...
    1982 Volume 55 Issue 6 Pages 1934-1938
    Published: 1982
    Released: June 27, 2006
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    Kinetic study of the leaching of powdered ilmenite ore was carried out in highly concentrated hydrochloric acid (11.3–11.6 mol dm−3) at temperatures of 30 to 80 °C. The changes in shape and grain size of the ore particles with progress of the leaching was simultaneously observed with X-ray diffraction and electron microscope techniques. Titanium and iron were dissolved in a nearly stoichiometric ratio; the rate of the dissolution was significantly affected by the temperature of the acid solutions. From the analysis of the dissolution rates on the basis of the core-model, it was found that the dissolution rates at temperatures of 30 to 50 °C were well expressed by the rate equation based on the rate-determining step of the surface chemical reaction. The apparent activation energies were 81.2 kJ mol−1 for titanium and 73.2 kJ mol−1 for iron. The rate-determining step of the dissolution was changed at a temperature of about 50–60 °C; the dissolution rates at temperatures of 60 to 80 °C were limited by the diffusion of the dissolved metal ions through a residual layer of the ore. However, the rates after 2 or 3 h at high temperatures deviated from the rate equation because of the precipitation of hydrous titanium(IV) oxide on the surface of the ore by hydrolysis of the dissolved titanium(IV) ion.
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