Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 61 , Issue 4
Showing 1-50 articles out of 79 articles from the selected issue
  • Tatsuya Yamazaki, Isao Watanuki, Sentaro Ozawa, Yoshisada Ogino
    1988 Volume 61 Issue 4 Pages 1039-1044
    Published: 1988
    Released: June 27, 2006
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    Amounts of nitrogen adsorbed by ion-exchanged ZSM-5 zeolites (H+, Li+, Na+, K+, Rb+, and Cs+) and silicalite have been measured under various conditions; pressure=6.7×102–6.7×104 Pa, temperature=196–273 K. IR spectra of adsorbed nitrogen have also been measured at 226 K under various nitrogen pressures (1.3×102–4.0×104 Pa). The adsorption capacity, the specific surface area, and the heat of adsorption have been evaluated from the adsorption data. These quantities coupled with the IR peak shifts observed have revealed that the nitrogen molecule adsorbed on a small and strong cationic site (Li+, Na+) has an orientation in which the longer molecular axis lies in parallel with the direction of the electric field of the cation site. It has also been revealed that the nitrogen molecule adsorbed on a large (K+, Rb+, Cs+) or weak (H+) cationic site takes on no special orientation. The electric field evaluated by analyzing the IR intensity is consistent with the adsorption model obtained.
  • Shoji Harada, Takayuki Sano, Teruyo Yamashita, Hiroshige Yano, Tadaomi ...
    1988 Volume 61 Issue 4 Pages 1045-1049
    Published: 1988
    Released: June 27, 2006
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    Micellar catalytic effects on the base dissociation of methylamine have been studied by ultrasonic absorption method. The dissociation constant, the rate constants, and the volume change of the reaction were obtained in the absence and in the presence of SDS. The micellar catalytic effects observed for methylamine was smaller than those for amines of long alkyl chain, which was ascribed to the facts that the former is incorporated into the micellar ionic atmosphere in the concentrated micellar solution while the latters are solubilized into micelles.
  • Jong-Ho Kim, Seitaro Namba, Tatsuaki Yashima
    1988 Volume 61 Issue 4 Pages 1051-1055
    Published: 1988
    Released: June 27, 2006
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    The alkylation of ethylbenzene with ethanol on ZSM-5 zeolites was studied at 673 K. The primary product in this alkylation on HZSM-5 catalyst was only p-diethylbenzene because of the transition-state selectivity. Therefore, the isomerization of p-diethylbenzene has to be restrained for the selective formation of p-diethylbenzene. The modified HZSM-5 catalysts with oxide of magnesium, phosphorus or boron showed much higher para-selectivity than the parent HZSM-5. The modification reduced not only the effective pore dimension of HZSM-5 but also the amount of strong acid sites. We claim that the absence of strong acid sites is necessary rather than the narrowness of pores for the suppression of the isomerization of p-diethylbenzene produced as a primary product.
  • Masamichi Yamada, Isao Ikemoto, Haruo Kuroda
    1988 Volume 61 Issue 4 Pages 1057-1062
    Published: 1988
    Released: June 27, 2006
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    Photooxidations of the evaporated films of rubrene, naphthacene, and pentacene were investigated by means of X-ray photoelectron spectroscopy. A rubrene film was found to be photooxidized far more easily than a naphthacene film although the molecules of rubrene and naphthacene in solution are known to be almost equally reactive for photooxidation. Although pentacene is photooxidized very easily in solution, the oxidation rate of a pentacene film was little enhanced by the light irradiation. Discussion is given on these behaviors of the evaporated films by considering the molecular packing in the solid state and the mechanism of photooxidation.
  • Yuriko Aoki, Akira Imamura, Takae Sasaki
    1988 Volume 61 Issue 4 Pages 1063-1070
    Published: 1988
    Released: June 27, 2006
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    The band structure of all-trans-polyacetylene is examined by using through space/bond interaction analysis. It is found that the cross-term in the perturbation expansion between two kinds of interactions governs the band shape near the gap: One kind is the interaction within the backbone, and the other is that between the backbone and the side chain. The relationship between the band structure and the symmetry of the interacting orbitals is also discussed.
  • Haruto Muraishi
    1988 Volume 61 Issue 4 Pages 1071-1075
    Published: 1988
    Released: June 27, 2006
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    The rate of the formation of talc from brucite powders with soluble silica under hydrothermal conditions was investigated in the temperature range of 400–460 °C, a range including the equilibrium temperature for the reaction: brucite+serpentine\ ightleftarrows2 forsterite+3H2O. Serpentine appeared as an intermediate phase below 415 °C, while above 430 °C forsterite appeared in addition to serpentine. The apparent reaction can be represented as:
    (Remark: Graphics omitted.)
    The reaction was apparently expressed as a pseudo-first-order reaction. The overall rate of the reaction did not increase with the increase in the temperature. Arrhenius plots of the rate constants for the overall reaction showed a curve with a maximum at about 415 °C and a minimum at about 445 °C which was caused by the alteration of the reaction by the appearance of forsterite at 430 °C.
  • Masakatsu Yonese, Kazuhiko Baba, Hiroshi Kishimoto
    1988 Volume 61 Issue 4 Pages 1077-1083
    Published: 1988
    Released: June 27, 2006
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    The counterion binding properties of alginate (Alg) sol and gel were studied by using the membrane potential method, in which membranes were constructed of an Alg layer sandwiched between supporting films. The concentrations of Alg WAlg ranged from 0.0025 to 0.0063 g cm−3, and the membrane potentials were measured in NaCl, MgCl2, and CaCl2 solutions. The effective charge densities of Alg (θ*2) were obtained by curve fittings with the theoretical values of the multimembrane potentials. The ratios of θ*2 to the concentration of uronate units θ0 were found not to depend on WAlg; their mean values were 0.45, 0.28, and 0.12 for Na-, Mg-, and CaAlg. The results of Na- and MgAlg in the sol state were bigger than Manning’s theoretical values. The much smaller values of CaAlg in the gel state than MgAlg in the sol state showed that the Ca ion binding was enhanced by the gellation not only in the junction, but also in the networks.
  • Fujiko Iwasaki, Yoshiaki Masuko, Sachiko Monma, Toshiya Watanabe, Kiyo ...
    1988 Volume 61 Issue 4 Pages 1085-1090
    Published: 1988
    Released: June 27, 2006
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    The crystal and molecular structures of N-phenyl-4-nitrobenzylamine (1), N-phenyl-4-nitrophenethylamine (2), and N-methyl-N-p-tolyl-4-nitrophenethylamine (3) have been determined by the X-ray method. The crystals of 1 are monoclinic, P21/n, a=16.924(1), b=8.792(1), c=7.642(1) Å, β=91.59(1)°, V=1136.8(1) Å3, Z=4, Dx=1.334 Mg m−3. 2 is triclinic, P\bar1, a=15.106(1), b=9.573(1), c=9.427(1) Å, α=113.22(1), β=91.27(1), γ=83.61(1)°, V=1244.7(2) Å3, Z=4, Dx=1.293 Mg m−3. 3 is trigonal, P31, a=b=8.435(1), c=17.758(1) Å, α=β=90°, γ=120°, V=1094.2 Å3, Z=3, Dx=1.231 Mg m−3. The final R values are 0.064, 0.059, and 0.045 for 1625, 3606, and 1131 observed reflections of 1, 2, and 3, respectively. About the amino-methylene N–C bond the phenyl group is trans to C for the molecules of 1 and 2, while in 3 the phenyl group is gauche to C about the N–C bond. The nitrophenyl plane of 3 is stacked on the p-toluidino plane of the neighbouring molecule alternately with the mean distance of 3.40 Å. The presence of the intermolecular CT interaction of 3 has been confirmed by the electronic absorption spectra of these compounds in the solid state.
  • Hideaki Fujiwara, Masayuki Watanabe, Yoshio Sasaki
    1988 Volume 61 Issue 4 Pages 1091-1094
    Published: 1988
    Released: June 27, 2006
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    1H NMR spectrum of the title compound was measured in a nematic liquid crystal ZLI1167 and analyzed utilizing modified versions of the LAOCN program. Direct couplings obtained were interpreted on the basis of a folded structure of tricyclic framework. The results show that the dihedral angle between the two benzene rings is 153.1±2.0° and the angle of S···N–H is 170.9±6.7°. Hence a “H-intra” conformation is dominant in a mobile state dissolved in the nematic liquid crystal. The preferred orientation of this molecule in ZLI1167 is discussed by comparing the results with those of the dibromo analogue reported previously and by comparing the principal axes of the order tensor with those of the moment of inertia. The chlorine and bromine atoms are supposed to exert a special steric effect on the ordering of these molecules.
  • Noboru Oyama, Takeo Ohsaka, Kazuyuki Chiba, Katsuhiko Takahashi
    1988 Volume 61 Issue 4 Pages 1095-1101
    Published: 1988
    Released: June 27, 2006
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    The homogeneous charge-transport process within electropolymerized electroactive poly(o-phenylenediamine) (PPD) films on graphite electrodes in various supporting electrolytic solutions (i.e., NaCl, NaClO4, Na2SO4, LiCl, CF3COONa, tetraethylammonium chloride (TEACl) and sodium p-toluenesulfonate (NaPTS)) at various pH’s was examined by potential-step chronoamperometry and chronocoulometry. The overall charge-transport process was found to obey Fick’s diffusion laws and thus the apparent diffusion coefficients (Dapp) for the diffusion-like charge-transport process were estimated. The Dapp values for the oxidation and reduction processes (i.e., Dappa and Dappc) were almost the same at pH 1.0 irrespective of the thickness of PPD films and were actually independent of the supporting electrolytes except for NaPTS. As pH was increased from 1 to 7, the Dappa values decreased slightly from ca. 5.6×10−8 to 1.6×10−8 cm2 s−1 and the Dappc values did more largely from ca. 5.6×10−8 to 2.2×10−9 cm2 s−1. This behavior was essentially common to all the supporting electrolytes examined. Such pH dependences of Dappa and Dappc are discussed on the basis of the fact that the charge-transport process within PPD films involves the intrinsic electron-transfer process between adjacent electroactive sites as well as the proton addition–elimination process, the charge-compensating counterion motion, the motion of solvent and the segmental motion of the polymeric chain. Especially, it is demonstrated that in this system the proton addition–elimination process must necessarily occur in order for the charge-transport process to proceed.
  • Tai-ichi Shibuya, Tadashi Funada, Haruo Gotoh
    1988 Volume 61 Issue 4 Pages 1103-1108
    Published: 1988
    Released: June 27, 2006
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    The equations-of-motion (EOM) method proposed by Shibuya and McKoy (Phys. Rev., A2, 2208 (1970); J. Chem. Phys. 58, 500 (1973)) has been extended to include (2p-2h)-state creation and annihilation operators in the excitation operator Oλ.
  • Tatsuo Ohgushi
    1988 Volume 61 Issue 4 Pages 1109-1113
    Published: 1988
    Released: June 27, 2006
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    The dielectric properties of completely dehydrated Rb3Na8–ZK4 zeolite were studied in the range 12–2.2×106 Hz and 211–705 K. Two kinds of losses, relaxation and conduction, were observed. The relaxation loss in the higher-frequency region had an activation energy of 99±2 kJ mol−1 and was tentatively assigned to a jump of the Rb+ ion from an 8-ring site to a vacant 4-ring site. The loss at the lower-frequency region had an activation energy of 95±3 kJ mol−1 and was attributed to a movement of the Rb+ ion on the 8-ring site beyond the unit-cell dimension.
  • Michiko Yoshitake, Kyuya Yakushi, Haruo Kuroda, Akiko Kobayashi, Reizo ...
    1988 Volume 61 Issue 4 Pages 1115-1119
    Published: 1988
    Released: June 27, 2006
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    Polarized reflectance spectra were measured on the single crystals of (BMDT-TTF)AsF6 and (BMDT-TTF)SbF6. The charge-transfer band was observed along the stacking direction in the crystals of (BMDT-TTF)AsF6, while in the crystal of (BMDT-TTF)SbF6 the charge-transfer band was found not only along the stacking direction but also along the S···S direction nearly parallel to the short axis of the BMDT-TTF molecule. The effective on-site Coulomb energies and the transfer integrals of these salts were estimated by analyzing the charge-transfer bands.
  • Kumao Hamanoue, Toshihiro Nakayama, Yoshiaki Yamamoto, Kazuhide Sawada ...
    1988 Volume 61 Issue 4 Pages 1121-1129
    Published: 1988
    Released: June 27, 2006
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    Photoreduction of anthraquinone (AQ) by triethylamine (TEA) in toluene and ethanol was studied by means of steady-state photolysis and laser photolysis. In toluene, addition of TEA enhanced the quantum yield of photoreduction of AQ, and the reaction was found to originate via the formation of an exciplex between ground-state TEA and the lowest triplet state of AQ: This exciplex changed to a contact ion pair followed by proton transfer, generating anthrasemiquinone radical and triethylamine radical, and 9,10-anthracenediol was obtained as the final photoproduct. Although the mechanism of the photoreduction of AQ in ethanol/TEA was essentially the same as that in toluene/TEA and the final products in ethanol/TEA were 9,10-anthracenediol and its anion, the quantum yield of photoreduction decreased with increase in TEA concentration. It was proposed that the exciplex in ethanol was quenched by ground-state TEA via the formation of a triplex of a radical anion of AQ and a radical cation of TEA dimer bonded by the three σ-electrons on two nitrogen atoms, based on the suggestion made by Hub et al. (J. Am. Chem. Soc., 106, 701 (1984); 106, 708 (1984)).
  • Tatsuya Sekine, Kazuho Inaba, Tatsumu Morimoto, Hidehiko Aikawa
    1988 Volume 61 Issue 4 Pages 1131-1134
    Published: 1988
    Released: June 27, 2006
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    The rate of solvent extraction of chromium(III) in aqueous perchlorate solutions into carbon tetrachloride as the tris(acetylacetonato) complex has been determined. The rate was first order with respect to the acetylacetone concentration and inverse first order with respect to the hydrogen-ion concentration. From this information, the rate-controlling reaction is concluded to be the formation of the first complex in the aqueous phase by a reaction between [Cr(OH)]2+ and HA.
  • Nobuyuki Sasaki, Kunihiko Watanuki
    1988 Volume 61 Issue 4 Pages 1135-1139
    Published: 1988
    Released: June 27, 2006
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    Changes in the chemical compositions of Tamagawa Hot Spring waters and Pb-bearing barite (hokutolite) were examined. Samples were obtained from various locations and various time in Tamagawa Hot Spring. The relationships between the hot spring waters and the minerals were expressed as partition equations and phenomenological equations; then, the partition coefficients and phenomenological coefficients were calculated. The apparent partition coefficients of Pb2+ and of Sr2+ between the two phases were found to have increased, from 0.14 to 0.30(0.31) and from 0.023 to 0.035(0.042) respectively, with the decrease in the hokutolite growth rate since 1973. The reaction rate of hokutolite as calculated from the phenomenological equations was, however, about 2 times higher in 1983 than in 1965. These results were ascribed to the rise in the degree of the supersaturation of barium sulfate and also to the increase in the nucleation rate in the hot spring water.
  • Tomoharu Ama, Hiroshi Kawaguchi, Takaji Yasui
    1988 Volume 61 Issue 4 Pages 1141-1146
    Published: 1988
    Released: June 27, 2006
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    Five cobalt(III) complexes, [(gly)2Co(μ-OH)2Co(en)2]2+ (two geometrical isomers), [(edda)Co(μ-OH)2Co(en)2]2+ (two geometrical isomers), and [(nta)Co(μ-OH)2Co(en)2]Cl, were newly prepared and optically resolved. Their structures were assigned on the basis of visible and UV absorption, 1H NMR, and circular dichroism (CD) spectral data. It was found that the CD contributions of the two different cobalt(III) chromophores are additive in the present complex systems. The vicinal CD which is induced on one of the two cobalt chromophores by the other chiral cobalt chromophore was strong (|Δε|: ca. 2). These complexes are stable for several days in aqueous solution.
  • Yasushi Inoue, Hiromichi Yamazaki, Mitsuji Ikeda
    1988 Volume 61 Issue 4 Pages 1147-1151
    Published: 1988
    Released: June 27, 2006
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    The rate of the isotopic exchange of sodium ions between the hydrous niobium(V) oxide ion exchanger in the Na+ form and aqueous solutions was determined radiochemically. Since the fractional attainment of equilibrium was independent of the sodium-ion concentration in the solutions (≥0.1 mol dm−3), and inversely proportional to the square of the particle radius, the isotopic exchange rate on the hydrous niobium(V) oxide is controlled by the diffusion of the sodium ions in exchanger particles. The self-diffusion coefficients of sodium ions (D=3.1×10−7 cm2 s−1 at 25 °C) and their activation energy (Ea=27±4 kJ mol−1) were also determined.
  • Yuji Sano, Hiroshi Wakita
    1988 Volume 61 Issue 4 Pages 1153-1157
    Published: 1988
    Released: June 27, 2006
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    Helium isotope ratios of terrestrial natural gas samples were measured using a high-precision mass spectrometer and an ultrahigh-vacuum purification line. The line is equipped with a charcoal trap held at 40 K using a helium expansion refrigerating machine. To avoid interference, Ne was completely separated from He by the trap before the gas was admitted to the mass spectrometer. Ion beams of 3He and 4He were measured at the same time by a double collector system. A resolving power of about 550 at the 5% level of the peak height was attained for the complete separation of 3He ions from those of HD and H3. Precision and reproducibility of the helium isotope ratio were less than 1%, examined by repeated measurements of an air standard. Accuracy of the ratio was checked by comparing observed data with reports in the literature.
  • Hitoshi Watarai, Yoko Horii, Mitsuaki Fujishima
    1988 Volume 61 Issue 4 Pages 1159-1162
    Published: 1988
    Released: June 27, 2006
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    A significant adsorptivity of tris(1,10-phenanthroline)iron(II), [Fe(phen)3]2+, at the interface of chloroform or carbon tetrachloride/0.1 M aqueous sodium chloride systems was determined by means of interfacial tension measurements at 25 °C. In the distribution systems of phen containing Zn(II) or Cu(II), a characteristic interfacial tension lowering was observed and interpreted in terms of an interfacial adsorption of metal–phen complexes.
  • Motohisa Fujiki, Toshio Deguchi, Isao Sanemasa
    1988 Volume 61 Issue 4 Pages 1163-1167
    Published: 1988
    Released: June 27, 2006
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    Formation constants of naphthalene and its (1- and 2-)methyl and (1,4-, 1,5-, and 1,8-)dimethyl derivatives with α-, β-, and γ-cyclodextrins (CyD) were determined in the aqueous medium in the presence of excess CyD. The technique used to study associations between host (CyD) and guest(hydrocarbon) is based on the facts that the guest molecules can be driven out to gaseous phase by introducing an inert gas at a constant flow rate into the aqueous solution and that the volatilization rate of guest decreases with increasing association with the host in aqueous solution. The 1:1 and 2:1 (host:guest) formation constants were evaluated at 25 °C. From the formation constant estimated, a host–guest spatial-fitting model for each association complex is presented.
  • Hisashi Kinoshita, Akira Ouchi
    1988 Volume 61 Issue 4 Pages 1169-1174
    Published: 1988
    Released: June 27, 2006
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    N-Methyl-2-piperidone adduct and dimethyl sulfoxide adduct of cobalt(II)mercury(II) thiocyanate were synthesized and their crystal and molecular structures were determined by the single-crystal X-ray diffraction technique. The former adduct is triclinic with a space group P\bar1, a=8.488(3), b=17.206(7), c=8.466(3) Å, α=103.72(1)°, β=90.00(1)°, γ=100.85(1)°, Z=2, while the latter adduct is orthorhombic with a space group P212121, a=8.418(3), b=27.389(10), c=8.407(3) Å, Z=4, and the final R values obtained were 0.059 and 0.066, respectively. In these adducts each mercury atom is in the tetrahedral geometry, coordinated with four sulfur atoms of the thiocyanate (SCN) ions, and each cobalt atom is in the octahedral geometry, coordinated with four nitrogen atoms of SCN ions and two oxygen atoms of the Lewis-base molecules which occupy the trans-positions. Each pair of different kinds of metal atoms are bridged by an SCN ion forming a 16-membered ring of Co2Hg2(SCN)4; these are linked, forming a two-dimensional network. The Lewis-base ligands are extended perpendicular to the plane on both sides. The complex layers are piled up in parallel, and there are no chemical or hydrogen bondings between the layers. This is a new type of the structure for CoHg(SCN)4L2 (L=Lewis base) type adducts.
  • Yusuke Okawa, Mitsunori Sukigara, Shoichiro Yoshida, Tadashi Watanabe
    1988 Volume 61 Issue 4 Pages 1175-1179
    Published: 1988
    Released: June 27, 2006
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    Semiconductor ion sensors based on the surface conductance change due to a variation in the depletion layer thickness have been constructed. An n-SnO2 electrode was coupled with four kinds of cation-sensitive polymer membranes (Fe3+- and Cu2+-exchanged Nafion membranes and poly(vinyl chloride)-supported dioctyl phthalate membranes containing a neutral carrier, valinomycin or nonactin), and its surface conductance was measured under depletion conditions as a function of the cation concentration. The sensor exhibited sensitivity to Fe3+, Cu2+, K+, or NH4+ at levels higher than 10−4 mol dm−3 within 10 s. The sensor response was analyzed in terms of (1) the dependence of the surface conductance on the surface band bending and (2) the potential difference at solution/membrane interfaces. From the analysis, it is confirmed that the membranes show nearly Nernstian behavior and that the semiconductor acts as a potentiometric transducer. The applicability of the depletion-mode semiconductor sensor is discussed.
  • Michinori Oki, Yasuhisa Yamada
    1988 Volume 61 Issue 4 Pages 1181-1184
    Published: 1988
    Released: June 27, 2006
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    The sulfur-inversion in the title compound (alkyl=ethyl) was found to take place with the following activation parameters by dynamic NMR spectroscopy: ΔH\ eweq=23.8±0.2 kcal mol−1, ΔS\ eweq=2.6±0.4 cal mol−1 K−1. The significance of the near zero entropy of activation is discussed. The mesityl group in the title compounds also showed restricted rotation of which barrier to rotation was estimated to be 14 kcal mol−1 at 318 K for the compound where the alkyl is a methyl.
  • Toshiari Morita, Michinori Oki
    1988 Volume 61 Issue 4 Pages 1185-1190
    Published: 1988
    Released: June 27, 2006
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    The rates of proton-detachment and those of topomerization in ammonium ions of benzyldiethylammonium chloride and benzylisopropylmethylammonium chloride were determined by dynamic NMR spectroscopy, by taking advantage of loss of coupling of the benzylic methylene or the methyl protons for the former process and site-exchange of the diastereotopic protons at the ethyl-methylene, isopropyl-methyl, or benzylic methylene positions for the latter in 1H NMR spectroscopy. The rates of the both processes were in good agreement with each other to indicate that the rate-limiting process in the observed topomerization is the proton-detachment. Thus it is shown that any available probes may be used for the proton-detachment or for the ivestigation of the proton affinity of amines by the dynamic NMR spectroscopy in aprotic solvents. The preference of the probes was discussed.
  • Michinori Oki, Yasuhisa Yamada
    1988 Volume 61 Issue 4 Pages 1191-1194
    Published: 1988
    Released: June 27, 2006
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    The rates of dissociation of thioether ligands which are imbedded in organotin(IV) compounds, such as trichloro[o-(ethylthiomethyl)phenyl]stannane, were determined by the dynamic NMR method. The dynamic processes of the corresponding ether ligands was too fast to detect as the change in line shapes in 1H NMR spectra. All the boron compounds examined, which possessed similar structures to the stannane and were of the boronate type, failed to show dissociation of a thioether or ether ligand due to their large rates of dissociation. The rates of dissociation of a thioether–tribromoboron complex were determined by the same technique. The feature of the activation parameters was that the compounds examined exhibited fairly large positive entropy of activation in accordance with other results that involve dissociation of ionic species into covalent species.
  • Akiko Nishida, Michinao Takamuku, Shizuo Fujisaki, Shoji Kajigaeshi
    1988 Volume 61 Issue 4 Pages 1195-1200
    Published: 1988
    Released: June 27, 2006
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    Several 9-substituted 9-(2-methylthiophenyl)fluorene derivatives and their oxidation products, 9-substituted 9-(2-methylsulfinylphenyl)fluorene derivatives were prepared. Each equilibrium constant was investigated and the conformational equilibria ap\ ightleftarrowssp of these compounds were discussed on the basis of nonbonding intramolecular interactions (attraction or repulsion) between 2-substituents in phenyl moieties (methylthio or methylsulfinyl) and fluorene ring or 9-substituents. It was found that the conformational equilibria were effected by the electronic properties of methylthio and methylsulfinyl groups. Kinetic data for internal rotation of a few compounds were shown.
  • Mitsuaki Narita, Shinya Honda, Hiroshi Umeyama, Toshihiko Ogura
    1988 Volume 61 Issue 4 Pages 1201-1206
    Published: 1988
    Released: June 27, 2006
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    Conformational analysis of human proinsulin C-peptide fragments bound to cross-linked and soluble polystyrene resin matrices was performed using IR absorption spectroscopy. The conformational analysis of octa- and tridecapeptides in the swollen and solid states revealed that both peptides easily interacted with each other through intermolecular hydrogen bonding to form a β-sheet aggregation even at a low loading of peptide chains on the matrices. The high potential of the resin-bound peptides for the β-sheet formation was compatible with that of the corresponding peptides free from macromolecular protecting groups and was predicted using the average coil conformational value, ⟨Pc⟩, of each peptide. The significance of the results is discussed in connection with solid-phase peptide synthesis. Effects of shear stress on conformational transformations of resin-bound peptides was also examined in the solid state.
  • Akiko Utagawa, Hiroshi Hirota, Shigeru Ohno, Takeyoshi Takahashi
    1988 Volume 61 Issue 4 Pages 1207-1211
    Published: 1988
    Released: June 27, 2006
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    Optically active (3R,7R,8R,1(10)E,4Z)-3-benzoyloxy-6-oxo-13-nor-1(10),4-germacradieno-12,8-lactone, a key synthetic intermediate for naturally occurring hiyodorilactone A, was prepared from (−)-carvone.
  • Hiroyuki Yamashita
    1988 Volume 61 Issue 4 Pages 1213-1220
    Published: 1988
    Released: June 27, 2006
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    The asymmetric ring opening of meso-2,3-disubstituted oxiranes with thiols, aniline, and trimethylsilyl azide was studied by the use of metal(II) d-tartrates as heterogeneous chiral Lewis acid catalysts. The enantioselectivity varied widely with the combination of oxirane, nucleophile, and metal(II) d-tartrate, and Zn(II) d-tartrate gave the best enantioselectivity in the respective reactions of 1,2-epoxycyclohexane with 1-butanethiol, aniline, and trimethylsilyl azide to afford the corresponding adducts in 85, 58, and 42% ee, respectively. Furthermore, the kinetic resolution of racemic oxiranes with thiols catalyzed by Zn(II) d-tartrate was studied.
  • Yasuhiro Tanoue, Akira Terada, Iwao Seto, Yasuo Umezu, Otohiko Tsuge
    1988 Volume 61 Issue 4 Pages 1221-1224
    Published: 1988
    Released: June 27, 2006
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    Hydroxylations of 2-(1-hydroxyalkyl)-1,4,5,8(or 1,4,5,6,8)-tetra(or penta)methoxynaphthalenes and 2-(1-hydroxyalkyl)-1,4-dimethoxybenzenes at the 3-position were accomplished by a one-pot procedure. The same procedure has been found to be applicable to 2-(1-hydroxyalkyl)naphthalenes and (1-hydroxyalkyl)benzenes having no methoxyl substituent.
  • Noritaka Abe, Toshiyuki Takehiro
    1988 Volume 61 Issue 4 Pages 1225-1230
    Published: 1988
    Released: June 27, 2006
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    The reaction of 1-methyl-1-azaazulen-2(1H)-one (1a) with dimethyl acetylenedicarboxylate (DMAD) or dibenzoylacetylene (DBA) in refluxing acetonitrile gave 1,2-disubstituted azulene (2), 2-methylcyclopent[de]isoquinolin-3(2H)-ones, 1-methyl-1-azacyclopent[cd]azulen-2(1H)-ones, and 3-substituted 1-methyl-1-azaazulen-2(1H)-ones, whereas in refluxing t-butylbenzene, compound 2 and 6,8-etheno-1-methylcyclohepta[b]pyrrol-2(1H)-one were obtained as major products. The reactions proceeded periselectively depending on the temperature. 2-Hydroxy-1-azaazulene behaved as 1-azaazulen-2(1H)-one and the reaction with DMAD gave similar result as for 1a. The reaction of 2-amino-1-azaazulene with DMAD gave methyl 2,4a-dihydro-2-oxo-1,4a-diazabenz[a]azulene-4-carboxylate and tetramethyl 4,5-dihydro-1H-1,11-diazacyclohept[a]azulene-2,3,4,5-tetracarboxylate. The reaction of 2-mercapto-1-azaazulene with DMAD gave tetramethyl 4,4a-dihydro-4a-azabenz[a]azulene-1,2,3,4-tetracarboxylate in moderate yield. The reaction mechanisms of these reactions are discussed.
  • Masayuki Kameyama, Hiroshi Shimezawa, Takeshi Satoh, Nobumasa Kamigata
    1988 Volume 61 Issue 4 Pages 1231-1235
    Published: 1988
    Released: June 27, 2006
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    Alkenesulfonyl chlorides reacted with vinylarenes in the presence of a catalytic amount of dichlorotris(triphenylphosphine)ruthenium(II) to give substituted 1:1 adducts, which were dehydrochlorinated and desulfonylated successively to form substituted (E,E)-1,3-dienes in good yield.
  • Motomitsu Kawai, Makoto Onaka, Yusuke Izumi
    1988 Volume 61 Issue 4 Pages 1237-1245
    Published: 1988
    Released: June 27, 2006
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    A new attempt of utilizing solid acid to the cross aldol reaction of silyl enol ethers with aldehydes or acetals has been investigated. Among solid acids employed, the reaction is promoted most effectively by a catalytic amount of aluminium ion-exchanged montmorillonite (Al-Mont). Simple diastereoselection is significantly sensitive to the nature of the reaction solvent used in the Al-Mont-catalyzed reaction. When the aluminium ions in Al-Mont were replaced by protons or titanium ions in order to investigate the cation effect, almost the same results were observed on simple diastereoselectivity and diastereofacial selectivity. This fact suggests that the metal cations in montmorillonite do not work as Lewis acid in the present aldol reaction. The acid catalysis of montmorillonite in the present aldol reaction is discussed in comparison with the catalytic behavior of some homogeneous acids.
  • Kunio Mochida, Kumiko Tashiro, Yasuhiro Yoshida, Yasuhisa Mizuno
    1988 Volume 61 Issue 4 Pages 1247-1249
    Published: 1988
    Released: June 27, 2006
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    Thermally generated germanium atoms were found to react with organic halides by insertion into carbon–halogen bonds. The resulting germylenes abstracted halogens from organic halides to form trihalogermyl derivatives. Tetrahalogermanes were also formed by the abstraction of halogens with germanium atoms.
  • Tae-il Son, Hisayoshi Yanagihara, Fumiyuki Ozawa, Akio Yamamoto
    1988 Volume 61 Issue 4 Pages 1251-1258
    Published: 1988
    Released: June 27, 2006
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    The double-carbonylation reaction of alkenyl halides with diethylamine in the presence of palladium catalysts has been examined in detail. The reaction gives α-keto amide together with amide, the single-carbonylation by-product. The yield of α-keto amide is strongly dependent on the nature of alkenyl halide. Alkenyl bromides or iodides having phenyl group(s) as substituent(s) on the vinyl group are successfully double-carbonylated under appropriate reaction conditions and the corresponding α-keto amides are obtained in good to modest yields together with amides. In contrast, the reactions of alkenyl halides without a phenyl group give amides exclusively. In order to clarify the reason for the substrate-specificity in the reaction, series of alkenyl- and alkenoylpalladium(II) complexes, the presumed intermediates in the catalytic reactions, have been prepared and their reactions with secondary amines, carbon monoxide, and alkenyl halides were examined. The study suggests the operation of three types of processes for amide formation in the catalytic reactions. Possible mechanisms for amide as well as α-keto amide formation are discussed.
  • Hitoshi Saito, Yoshio Nishimura, Shinichi Kondo, Tomio Takeuchi, Hamao ...
    1988 Volume 61 Issue 4 Pages 1259-1263
    Published: 1988
    Released: June 27, 2006
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    Glycosidic variants of 1-β-hydroxy-α-peltatin and 1-β-hydroxy-8-O-methyl-α-peltatin were synthesized by glycosidation of 4′,8-di-O-benzyloxycarbonyl-1-β-hydroxy-α-peltatin or 4′-O-benzyloxycarbonyl-1-β-hydroxy-8-O-methyl-α-peltatin with the corresponding glucopyranose or 2-amino-2-deoxyglucopyranose derivatives. Among synthesized compounds, cyclic acetal of 1-O-β-(β-D-glucopyranosyl)-8-O-methyl-α-peltatin showed antitumor activity in mice with leukemia L-1210.
  • Yuji Hidaka, Hirokazu Kubota, Shoko Yoshimura, Hideaki Ito, Yoshifumi ...
    1988 Volume 61 Issue 4 Pages 1265-1271
    Published: 1988
    Released: June 27, 2006
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    Heat-stable enterotoxins, produced by various enteric bacteria such as enterotoxigenic Escherichia coli, Yersinia enterocolitica, and Vibrio cholerae non-01, have common segments consisting of 13 amino acid residues (T. Takao et al., FEBS Lett., 193, 250 (1985)). These segments have full enterotoxigenic activity and are bound by three intramolecular disulfide bonds. The linkages of these three disulfide bonds in a heat-stable enterotoxin (STp) produced by a porcine strain of enterotoxigenic E. coli were determined to be
    (Remark: Graphics omitted.)
    by stepwise and selective formation of disulfide bonds using different types of removable protecting groups for Cys residues. These disulfide linkages were identical with those of a heat-stable enterotoxin (STh) produced by a human strain of enterotoxigenic E. coli (Y. Shimonishi et al., FEBS Lett., 215, 165 (1987)).
  • Tamotsu Fujisawa, Atsushi Fujimura, Toshio Sato
    1988 Volume 61 Issue 4 Pages 1273-1279
    Published: 1988
    Released: June 27, 2006
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    Both enantiomers of various optically pure (R)- and (S)-β-hydroxy esters were generally synthesized from (S)-(p-chlorophenylsulfinyl)acetone obtained by kinetic resolution with bakers’ yeast, followed by γ-alkylation, diastereoselective reduction, subsequent introduction of ester group and reductive elimination of the sulfinyl group. The key step of the diastereoselective reduction of (S)-β-keto sulfoxides was performed with diisobutylaluminum hydride to give (R)c-(S)s-β-hydroxy sulfoxides or after complexation with zinc chloride followed by addition of diisobutylaluminum hydride to give (S)c-(S)s-β-hydroxy sulfoxides which were easily separated in an optically pure form by easy crystallization or separation by silica-gel chromatography due to the p-chlorophenyl moiety in the β-hydroxy sulfoxides. The utility of the present method could be successfully demonstrated in the synthesis of both (+)- and (−)-corynomycolic acids from optically pure methyl esters of (R)- and (S)-3-hydroxyoctadecanoic acid by alkylation with tetradecyl iodide at α-position and hydrolysis.
  • Koji Yamamoto, J\={u}ro Ojima, Noboru Morita, Toyonobu Asao
    1988 Volume 61 Issue 4 Pages 1281-1283
    Published: 1988
    Released: June 27, 2006
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    The synthesis of the title compound, a double-layered annulene with 10π-rings, is described. The examination of 1H NMR and electronic spectra suggests that the layered compound exhibits appreciable interaction between two [10]annulene rings.
  • Koji Tanaka, Mari Masanaga, Toshio Tanaka
    1988 Volume 61 Issue 4 Pages 1285-1289
    Published: 1988
    Released: June 27, 2006
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    Electrochemical reduction of [Fe4S4(SC6H4-p-n-C8H17)4]2− ([4-Fe]2−) dissolved in a CH2Cl2 phase of the CH2Cl2/H2O two phase system is followed by protonation to give [4-Fe]3−–H+ when the pH of the H2O phase is lower than 7.0, and protonated and deprotonated [4-Fe]3− exist as an equilibrium mixture in the CH2Cl2 phase. On the other hand, no protonation takes place upon the reduction of [4-Fe]2− in the CH2Cl2 phase contacting with the H2O phase with the pH higher than 7.0. The electron transport conducted in a liquid membrane composed of the H2O (W1), CH2Cl2, and H2O (W2) phases containing sodium dithionite as an electron donor, (n-Bu4N)2[4-Fe] as a mediator, and disodium anthraquinone-1,5-disulfonate (Na2AQS) as an electron acceptor, respectively, revealed that protonated [4-Fe]3−–H+ mediates electron coupled proton transport in the liquid membrane, while the deprotonated cluster has no ability of electron transport in the same system.
  • Eisuke Kaji, Frieder W. Lichtenthaler, Takashi Nishino, Aya Yamane, Sh ...
    1988 Volume 61 Issue 4 Pages 1291-1297
    Published: 1988
    Released: June 27, 2006
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    Highly stereoselective, expedient syntheses are described for three immunologically relevant β-glycosides of N-acetyl-D-mannosamine, i.e. β-D-ManpNAc-1-OMe (8), β-D-ManpNAc-(1→6)-D-Gal (15), and β-D-ManpNAc-(1→4)-α-D-Glcp-1-OMe (23). Basic mannosamine progenitor in each case is 3,4,6-tri-O-benzoyl-2-(benzoyloxyimino)-2-deoxy-α-D-arabino-hexopyranosyl bromide (1a), which via the three step-sequence β-selective glycosidation → hydroboration → deblocking is converted to 8, 15, and 23 in overall yields of 61, 56, and 39% for the glycosyl acceptors methanol, 1,2:3,4-di-O-isopropylidene-α-D-galactose, and methyl 2,3,6-tri-O-benzyl-α-D-glucopyranoside, respectively.
  • Masaaki Suzuki, Toshio Kawagishi, Akira Yanagisawa, Takehiko Suzuki, N ...
    1988 Volume 61 Issue 4 Pages 1299-1312
    Published: 1988
    Released: June 27, 2006
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    A one-pot, high yield construction of the whole prostaglandin (PG) skeleton is accomplishable by combination of the copper-mediated conjugate addition of an ω side-chain unit to a 4R-oxygenated 2-cyclopentenone derivative and aldol condensation of the in situ generated enolate with an α side-chain aldehyde. Subsequent removal of the 7-hydroxyl group from the adducts and deblocking of the protective groups give PGs of E series. PGE1 has been prepared in 56% overall yield through the five-step sequence. Selective transformation of the PGE to PGD structure can be realized simply by appropriate selection of the hydroxyl protective groups in the five-membered ring and ω side-chain units. The vicinal carba-condensation using methyl 6-formyl-5-hexynoate as the α side-chain aldehyde unit followed by deoxygenation from the aldol products gives the 5,6-didehydro-PGE2 derivatives which serve as key intermediates in the general synthesis of various natural PGs. An efficient method for resolution of 4-hydroxy-2-cyclopentenone is also described.
  • Yukinori Dairaku, Satoshi Sato, Toshiaki Sodesawa, Fumio Nozaki
    1988 Volume 61 Issue 4 Pages 1313-1317
    Published: 1988
    Released: June 27, 2006
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    For the oxidative sorption of SO2 using Fe2O3/CaO binary sorbents prepared by the usual impregnation method, reactivities and capacities for SO2 removal have been investigated with TG measurements at temperatures near 500 °C in a stream of air containing SO2 in concentration from 2 to 11%. Both the reactivities and the capacities of the sorbents were exceedingly enhanced by addition of Fe2O3 into CaO such small amounts as 0.1–0.8wt%, and further Fe2O3-loading over 1.0wt% resulted in a lowering in promoting effects. The changes in surface area and pore-size distribution with a variation of Fe2O3 content were also measured in order to discuss the correlation between chemical reactivity for SO2 removal and physical property of the Fe2O3/CaO sorbents. In addition, Fe2O3–CaO mechanically mixed sorbents and the other binary sorbents such as Fe2O3/MgO or V2O5/CaO were tested to compare with the Fe2O3/CaO sorbents.
  • Sang-Heon Hyun, Hiroyuki Nishide, Eishun Tsuchida, Shigetoshi Yamada
    1988 Volume 61 Issue 4 Pages 1319-1322
    Published: 1988
    Released: June 27, 2006
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    2-Methyl-6-(3,7-dimethyl-2,6-octadienyl)phenol (MGP) was prepared by the reaction of o-cresol and 1-chloro-3,7-dimethyl-2,6-octadiene in the presence of sodium. This MGP was then oxidatively polymerized with a copper-pyridine catalyst to yield poly[oxy[3-methyl-5-(3,7-dimethyl-2,6-octadienyl)-1,4-phenylene]]. The MGP and 2,6-dimethylphenol (DMP) copolymerized with a similar reactivity to form copolymer. The properties of the polymers were also studied.
  • Kiyofumi Murakami
    1988 Volume 61 Issue 4 Pages 1323-1329
    Published: 1988
    Released: June 27, 2006
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    The interaction between Orange I (sodium 4-[(4-hydroxy-1-naphthalenyl)azo]benzenesulfonate) and bovine serum albumin (BSA) at pH=7.0 and 25 °C has been studied by equilibrium dialysis, spectrophotometry, and the temperature-jump method. Equilibrium dialysis has revealed the existence of sixteen equivalent binding sites with the binding constant of K=9.7×103 M−1. All of them were found to be equivalent also in the sense of spectrophotometry. That is, Orange I interacts with BSA in a typically nonspecific manner. Five relaxations were found by the temperature-jump measurements. These relaxation times, distributed over the time range from 10 μs to 0.1 s, were determined over a wide range of reactant concentrations. The fastest relaxation becomes slow, but the four slower ones become fast, with the increase in the concentration of the free ligand. The data were interpreted by means of a combination of the bimolecular binding processes and the four isomerization modes of BSA. The results were discussed in the light of the role of the configurational adaptability of albumin molecules in the ligand-binding mechanism.
  • E. A. Hassan, K. M. Abd El-Salaam, A. A. Said
    1988 Volume 61 Issue 4 Pages 1331-1334
    Published: 1988
    Released: June 27, 2006
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    Decomposition of hydrogen peroxide in aqueous solution was used for testing the effect of gamma radiation on the catalytic activity of CoxFe3−xO4, with O≤x≤3.0. The activity variation was interpreted in terms of the catalysts electronic structure. The presence of Co2+ on octahedral sites is superior to Fe2+ in the catalytic process. However, γ-irradiation can produce a considerable effect on the catalytic activity due to its influence on the active site concentration and cation distribution.
  • Ahmed M. Nour El-Din, Abdel-Razak Tawfik
    1988 Volume 61 Issue 4 Pages 1335-1337
    Published: 1988
    Released: June 27, 2006
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    Charge-transfer (CT) complexes between some α-aryl and α-(heterocyclic substituted)nitrones and iodine as σ-acceptor in dichloromethane have been investigated spectrophotometrically. From the energies of the charge-transfer transitions, the ionization potentials of the nitrones have been obtained. The stoichiometry of the complexes has been determined. All the results are in agreement with the n–σ* nature of these complexes with some involvement of the π-orbital of the donor.
  • M. Z. A. Badr, A. M. Mahmoud, S. A. Mahgoub, Z. A. Hozien
    1988 Volume 61 Issue 4 Pages 1339-1344
    Published: 1988
    Released: June 27, 2006
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    2-Hydrazinobenzoxazole (1), -benzimidazole (2), and benzothiazole (3) were condensed with ethyl chloroformate and/or diethyl oxalate to produce, 1,2,4-triazolo- and 1,2,4-triazino-fused ketones of the title azoles respectively. Condensation of 1 and 2 with aromatic aldehydes and/or acetic anhydride produced, 3-aryl- and 3-methyl-substituted 1,2,4-triazolo-fused azoles respectively. The hydrazines 1 and 2 cyclized with acetylacetone to produce the corresponding 2-(1-pyrazolyl) derivatives. 2-Acetylthiazolobenzimidazole reacted with hydroxylamine and/or alkylamines, to produce the corresponding condensation products. Also it condensed with aromatic aldehydes to give the chalcones. When reacted with benzenediazonium salt, it gave the corresponding 2-arylazo-substituted compounds.
  • Zarif Haleem Khalil, Amal Sabet Yanni, Ali Ali Khalaf, Ali Ali Abdel-H ...
    1988 Volume 61 Issue 4 Pages 1345-1349
    Published: 1988
    Released: June 27, 2006
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    Interaction of 5-acetyl-8-quinolinol, corresponding 1-ethylquinolinium iodides, and 8-hydroxyquinoline-7-carbaldehyde with diethylmalonate under basic condition gave the corresponding of 46. Further reaction of 46 with hydrazine, phenyl hydrazine, hydroxylamine, urea, and/or thiourea gave the corresponding 1-[8-hydroxy-5(7)-quinolinyl]alkylidene-substituted heterocyclic derivatives (716) and corresponding 1-ethylquinolinium iodides (1721). The structure of the synthesized compounds was confirmed by elemental and spectral analysis. The biological activity of 5-substituted 8-quinolinol was tested as microbicidal and bioregulator agents, the results obtained were interpreted according to their structure-activity relationships.
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