Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 51 , Issue 6
Showing 1-50 articles out of 78 articles from the selected issue
  • Jun-ichiro Take, Toshiaki Ueda, Yukio Yoneda
    1978 Volume 51 Issue 6 Pages 1581-1584
    Published: 1978
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    We investigated the effect of NaOH impregnation on the acidic properties (the type, strength, and amount of acid sites) of silica-alumina by means of IR spectroscopy of chemisorbed pyridine. Most acid sites on the unpoisoned catalyst were of the Lewis type. Some Lewis-bound pyridine was retained on the surface even at 400 °C, but the pyridinium ion was eliminated at 300 °C, indicating that the strong acid sites were also of the Lewis type. Impregnated NaOH affected both Lewis and Brønsted sites. An increase in the amount of NaOH resulted in the elimination of the Brønsted acid sites of medium strength, and also in a significant reduction in the number of Lewis acid sites over the whole range of acid strength. Weak Brønsted acid sites showed no marked change in number. When the NaOH-impregnated catalysts were exposed to pyridine, a new IR band appeared at about 1445 cm−1; this band is attributable to pyridine associated with the Na ions on the surface.
  • Akio Nakamura, Shigeru Yamauchi, Kazuo Fueki, Takashi Mukaibo
    1978 Volume 51 Issue 6 Pages 1585-1588
    Published: 1978
    Released: April 19, 2006
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    In order to obtain information on the defects in ternary oxide systems, the nonstoichiometry and electrical conductivity of BaFe2O4 were determined at temperatures between 1050 and 1125 °C. The electrical conductivity was found to be proportional to PO2−1⁄6. This relationship suggests that BaFe2O4 is an oxygen deficient n-type semiconductor at high temperatures. The nonstoichiometry was proportional to PO2−1⁄2.88. order to interpret the dependence of electrical conductivity and nonstoichiometry on the oxygen partial pressure, various defect models were examined. As a result the following equilibria were selected from among the oxygen vacancies V0·· and V0x, and oxygen gas.
    null=(1⁄2)O2+V0x
    V0x=V0··+2e
    An analysis based on the above defect model explains the data well.
  • Masashi Hirota, Takao Iijima, Masao Kimura
    1978 Volume 51 Issue 6 Pages 1589-1593
    Published: 1978
    Released: April 19, 2006
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    The molecular structure of 2,2-dichloropropane has been determined by the joint analysis of the electron-diffraction data and the moments of inertia obtained by Matsumura and Takeo by means of microwave spectroscopy. Under the assumptions that rg(C–H) is in the range of 1.100–1.110 Å and that \varphia(HCH.) is larger than 107.0°, the structure parameter values have been determined (with the limits of error in parentheses) to be as follows: rg(C–Cl), 1.799(3) Å; rg(C–C), 1.523(4) Å; rg(cl…Cl), 2.910(1) Å; rg(C…Cl), 2.702(1) Å; \varphiav(ClCCl), 108.3(3)°, and \varphiav(CCC), 113.0(4) °. The rg-structure determined in the present study is in perfect conformity with the r0-structure determined by Matsumura and Takeo. The C-Cl and C-C distances are shorter than the corresponding distances in 2-chloropropane.
  • Masashi Hirota, Takao Iijima, Masao Kimura
    1978 Volume 51 Issue 6 Pages 1594-1598
    Published: 1978
    Released: April 19, 2006
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    The molecular structure of ethyl chloride has been determined by a joint analysis of the electron-diffraction data and the moments of inertia obtained by Schwendeman and Jacobs by means of microwave spectroscopy. In the analysis, a staggered conformation with Cs symmetry for the molecule and a local C3v symmetry about the C–C axis for the methyl group were assumed. Under the further assumptions that \varphiav(HCH)CH2 is 109.2±2° and \varphiav(CCH)CH2 is in the range of 113.6–109.6°, the following parameter values were determined: rg(C–C) 1.528(4) Å; rg(C–Cl), 1.802(3) Å; rg(C–CI), 2.746(5) Å; rg; rg(C–H)CH2, 1.103(4) Å; \varphiav(HCH)CH2, 110.0(1.6)°; and \varphiav(CCCl), 110.7(0.3) °. The rg and rs distances for the C–Cl and C-C bonds of various chlorinated alkanes were plotted against the difference between the numbers of methyl groups and chlorine atoms, Δn=n(CH3)–n(Cl). In general, as the number of chlorine atoms increases, both distances become shorter, though the rg distances are longer than the rs distances by 0.01–0.03 Å.
  • Masahiro Manabe, Masaharu Koda
    1978 Volume 51 Issue 6 Pages 1599-1601
    Published: 1978
    Released: April 19, 2006
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    The effect of the addition of the homologues of poly(oxyethylene) alkyl ethers (CmH2m+1(OCH2CH2)nOH: m=3–6, n=1–4), α,ω-alkanediols (m=4–6,8), and 1-alkanols (m=2–7) on the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS) was examined. The homologous additives are appropriate for studying the effect of polar groups as well as an alkyl group. The CMC decreases with an increase in the concentration of additive. The rate of CMC-decrease estimated at the infinite dilution of the additive increases with the length of alkyl chain in each homologue. The dependence of the rate on the alkyl chain length is the same for all the homologues with longer chain (m≥4 for ethers and alkanols, and m>6 for alkanediols). This is ascribed to the complete transfer of the long alkyl chain into the interior of micelles. The dependence of rate on the number of polar groups (OH, OCH2CH2) is as follows. The rate for alkanediol is lower than that for alkanol with a given alkyl chain. The rate for ethers increases asymptotically with the length of oxyethylene chain. The result for alkanediol is ascribed to the pronounced hydrophilic nature, and that for ethers to the reduction of electrostatic repulsive force between ionic head groups of the surfactant in micelles.
  • Fumio Watari, Shigenori Shimizu, Koyo Aida, Eiji Takayama
    1978 Volume 51 Issue 6 Pages 1602-1608
    Published: 1978
    Released: April 19, 2006
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    Studies were carried out on the infrared spectra (33–4000 cm−1) of four isotopic trimethylaluminium–ammonia complexes, (CH3)3AlNH3, (CD3)3AlNH3 (CH3)3AlND3, and (CD3)3AlND3 in the solid state at low temperature, and on the Raman spectra (0–4000 cm−1) in the solid state and in solution of dichloromethane and of benzene at ambient temperature. Assignments for all fundamentals except internal torsion were made on the basis of C3v molecular symmetry. For the sake of confirmation normal coordinate calculations were carried out utilizing a symmetry force field. The Al–N stretching force constant was found to be 1.544 mdyn/Å.
  • Hiroshi Tochihara, Yoshitada Murata
    1978 Volume 51 Issue 6 Pages 1609-1611
    Published: 1978
    Released: April 19, 2006
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    Reaction cross sections of the reaction CO2++D2→DCO2++D have been measured over the range of the collision energies E=0.4 to 4 eV in the center of mass system. The cross section was obtained from relative values of the reaction Ar++D2→DAr++D by using the mixed ion beam method. The observed cross sections are about half of the Langevin-Gioumousis-Stevenson cross sections and show approximately E−1⁄2 dependence.
  • Jun-ichiro Take, Tadayuki Matsumoto, Yukio Yoneda
    1978 Volume 51 Issue 6 Pages 1612-1616
    Published: 1978
    Released: April 19, 2006
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    In order to survey the applicability of linear free-energy relationships to the catalytic dehydration of aliphatic alcohols, isopropyl alcohol and n-, s-, and t-butyl alcohols were dehydrated over silica–alumina at 54–166 °C. The dehydration was zero order in alcohol over the pressure range of 0.01 to 0.1 atm. The true activation energies were 32.0, 35.3, 31.7, and 29.9 kcal/mol for isopropyl alcohol and n-, s, and t-butyl alcohols, respectively. The zero-order rate constants were exclusively affected by the activation energy. A linear relationship was found between the true activation energy, as well as the logarithm of the zero-order rate constant, and the heterolytic bond dissociation energy for the C–O bond in alcohols, D(R+OH). The activation energy increased and the rate constant decreased with an increase in the D(R+OH). These correlations were explained in terms of the heterolytic fission of the C–O bond in the rate-determining step.
  • Nobuo Nishino, Masao Nakamura
    1978 Volume 51 Issue 6 Pages 1617-1620
    Published: 1978
    Released: April 19, 2006
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    The change in the solubility in water with the temperature was measured for alkanols, alkylamines, and alkanoic acids. It has been found that a minimum exists commonly on the solubility-temperature curve. This minimum dissolution point, Pm, may be regarded as a characteristic point with respect to the solute. The change in the solubility with the temperature has been explained in terms of the increase in the partial molar enthalpy of the solute in solution with an increase in the temperature, which results from the breakdown of the ice-like structure of water formed around the nonpolar alkyl group. Both the concentration, xm, and temperature, Tm, at point Pm decrease with an increase in the number of carbon atoms in the alkyl group, m. The decrease in In xm by the addition of one methylene group is steeper in the order of alkanoic acids, alkylamines, and alkanols, while the corresponding decrease in Tm shows the reverse order. In addition, Tm is related to the cohesive energy of the solute in the pure state.
  • Tsutomu Minato, Hiroshi Fujimoto, Kenichi Fukui
    1978 Volume 51 Issue 6 Pages 1621-1626
    Published: 1978
    Released: April 19, 2006
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    The bond interchange in the course of the addition of amine to carbonyl has been studied by means of a localized molecular orbital method with a clear chemical-bond concept, and the mechanism of the addition has been elucidated theoretically. It is ascertained by the present calculation that the charge transfer interaction from the highest occupied molecular orbital of amine to the lowest unoccupied molecular orbital of carbonyl is of importance to form a new nitrogen-carbon bond. Furthermore, the stereospecificity of the nucleophilic addition to a double or triple bond has been studied. When an intermediate is created by the addition of a nucleophile to the unsaturated bond, it is suggested that the intermediate is reactive for the electrophilic attack on the side trans to the new bond formed by the first attack. This is reasoned in terms of the mode of orbital interaction.
  • Kazuaki Harata, Hisashi Uedaira, Jiro Tanaka
    1978 Volume 51 Issue 6 Pages 1627-1634
    Published: 1978
    Released: April 19, 2006
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    α-Cyclodextrin (α-CDx) forms a 1 : 2 crystalline complex with m-nitrophenol (m-NP). The crystal structure was determined by the X-ray method. The crystal is orthorhombic, and the space group is P21212 with Z=2. The cell dimensions are a=22.231(7), b=16.865(6), and c=8.152(1) Å. The structure was solved on the basis of the nearly isomorphous structure of the α-CDx-sodium benzenesulfonate complex by using 2246 reflections, and refined by the block-diagonal least-squares method to the final R-value of 0.10. The framework of the crystal is built up of a stack of α-CDx molecules with a head-to-tail arrangement along the two-fold axis, showing a channeltype structure. Two m-NP molecules are statistically disordered on the two-fold axis. One is located in the channel, while the other is sandwiched between the α-CDx molecules. In the channel, the nitro group of m-NP is inserted into the α-CDx ring from the secondary hydroxyl side, and the phenolic hydroxyl group is hydrogen-bonded to the primary hydroxyl group of the next α-CDx molecule. The enthalpy change was calculated for the complex formation in an aqueous solution. The calculated results are in qualitatively agreement with the observed values. The catalytic ability of α-CDx in the hydrolysis of substituted phenyl acetates was discussed on the basis of the structural data.
  • Noritetsu Yoshida, Shuji Saito
    1978 Volume 51 Issue 6 Pages 1635-1638
    Published: 1978
    Released: April 19, 2006
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    Microwave spectroscopy has been applied to the determination of the rate constant for OCS+O→SO+CO. A short cell of a parallel-plate type was devised for the detection of the SO radicals produced in a fast flow reactor. Production of the SO radical was traced by measuring its spectral line intensity under the condition of [OCS]>>[O]. The rate constant for the reaction was determined to be (7.1±0.7)×109 cm3/mol·s at room temperature (24–25) °C, in good agreement with the values obtained by other methods.
  • Y\={u}k\={o} Taira, Kunio Matsuda, Koichiro Nakanishi
    1978 Volume 51 Issue 6 Pages 1639-1643
    Published: 1978
    Released: April 19, 2006
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    The diffusion coefficients of argon in water-rich regions of aqueous solutions of ethanol and of 1,4-dioxane and those of methane in aqueous solutions of ethanol have been measured by using a diaphragm cell apparatus, designed after Hildebrand et al., for dissolved gases in liquid. The diffusivity of gases was found to show much anomaly which might be ascribed to the structural change of water due to the addition of another solvent. The viscosity reduced diffusion coefficient Dη (D: diffusion coefficient, η: viscosity coefficient) has a maximum value in dilute aqueous solution of both ethanol and 1,4-dioxane.
  • Kazuaki Harata
    1978 Volume 51 Issue 6 Pages 1644-1648
    Published: 1978
    Released: April 19, 2006
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    The crystal structure of the α-cyclodextrin(α-CDx)–DMSO–methanol (1 : 1 : 2) dihydrate complex was determined by the X-ray method. The crystal is monoclinic, and the space group is P21 with Z=2. The cell dimensions are a=9.505(1), b=14.150(1), c=19.738(2) Å, and β=102.88(1)°. The structure was solved by an inspection of a Patterson map and by a trial-and-error method, and was refined by the block-diagonal least-squares method to the final R-value of 0.083 for 3732 reflections. The α-CDx ring is nearly hexagonal, with diagonal distances of 8.40–8.53 Å between the glycosidic oxygen atoms. The α-CDx molecules are arranged to form molecular layers perpendicular to the ac plane. The DMSO molecule is located on the secondary hydroxyl side in the α-CDx cavity, forming two hydrogen bonds with the adjacent α-CDx molecules. One methanol molecule is found on the primary hydroxyl side in the cavity, while the other is located outside the cavity. Two water molecules are distributed in the space between α-CDx molecules.
  • Norio Ohtomo, Kiyoshi Arakawa
    1978 Volume 51 Issue 6 Pages 1649-1654
    Published: 1978
    Released: April 19, 2006
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    The structure factor for heavy water at 17 °C up to the Q value of 18 Å−1 has been determined by means of the time-of-flight (TOF) diffraction method using pulsed neutrons produced by LINAG. The result has been compared with structure factors calculated on the basis of the various structure models of liquid water; the “uncorrelated orientation model” and the “watery model” (Page and Powles), the “near-neighbor model” (Narten) and the “revised watery model” (authors). None of these models has been found to fit the neutron diffraction data satisfactorily over the entire range of Q, though our curve is somewhat improved in comparison with the curves for earlier models. Some discussions about the various structure models of liquid water have been made.
  • Tsunetake Fujiyama, Masami Tanaka
    1978 Volume 51 Issue 6 Pages 1655-1658
    Published: 1978
    Released: April 19, 2006
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    Light scattering spectra were observed for binary mixtures of ethanol and carbon tetrachloride, and of ethanol and cyclohexane at various concentrations. The Rayleigh intensities were reduced to concentration fluctuation values. From the observed concentration fluctuation values, the mean association numbers of ethanol at each concentration were calculated. The results were compared with that observed in ethanol-chloroform system, where associative interaction between ethanol and chloroform molecules is expected. The concentration dependencies of the mean association numbers suggested that these non-associative solvent molecules (carbon tetrachloride and cyclohexane) promote the formation of large local structure in ethanol solution.
  • Yoshiaki Hidaka, Midori Nagayama, Masao Suga
    1978 Volume 51 Issue 6 Pages 1659-1644
    Published: 1978
    Released: April 19, 2006
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    A part of the mass-spectrometer shock-tube apparatus was improved, and its working characteristics were examined. The oxidation of methane was studied with this apparatus over the temperature range of 1800–2500 K and the total pressure range of 360–560 Torr at O2/CH4 ratios of 1–3. The induction period was measured by monitoring the oxygen concentration, and the following equation was found to hold:
    τ=4.54×10−10[CH4]0.37[O2]−0.64exp(35600⁄RT) s
    in which the concentrations were expressed in mol per cubic centimeter.
  • Kazumoto Nakamura, Seiichro Koda, Kazuo Akita
    1978 Volume 51 Issue 6 Pages 1665-1670
    Published: 1978
    Released: April 19, 2006
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    The mercury photosensitized decomposition of 3-cyclopenten-1-one produced carbon monoxide and 1,3-butadiene in equal quantum yields as the exclusive products, independent on the absence or presence of nitrogen oxide. Thus the process was a molecular dissociation. The quantum yield was dependent on the pressure of argon added as a third body and revealed a maximum at the pressure of about 100 mmHg. A possible reaction scheme was proposed to explain the above kinetic behavior. It was suggested that the vibrationally excited state of 3-cyclopenten-1-one was a main precursor to decompose to carbon monoxide and 1,3-butadiene. An energy about 20 kcal·mol−1 was estimated to be lost before its production from the original triplet state 3-cyclopenten-1-one according to the proposed reaction scheme. This result is compared with the behaviors of excited 3-cyclopenten-1-ones produced by different excitation procedures.
  • Ryoichi Nakagaki, Takayoshi Kobayashi, Saburo Nagakura
    1978 Volume 51 Issue 6 Pages 1671-1675
    Published: 1978
    Released: April 19, 2006
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    The luminescence behavior of 2-(2-hydroxyphenyl)benzothiazole at 77 K was studied in detail, special attention being paid to dual fluorescence at ≈500 and ≈370 nm and also to phosphorescence at ≈500 nm. From the dependence of these emission bands upon the hydrogen-bonding ability of solvents and the excitation spectra, it is concluded that the short- and long-wavelength fluorescence bands are due to the intermolecularly hydrogen-bonded enol imine and the keto amine produced from the intramolecularly hydrogen-bonded enol, respectively, and that the phosphorescence is due to the intermolecularly hydrogen-bonded enol imine. The estimated quantum yield of the enol fluorescence gives further support to the formation scheme of the photochromic colored species previously presented. The rate constants of the intramolecular hydrogen transfer at 77 and 293 K are evaluated to be larger than 4×1010 s−1 and 3×1012 s−1, respectively.
  • Tetsuo Miyazaki, Joji Kasugai, Manabu Wada, Kazuhisa Kinugawa
    1978 Volume 51 Issue 6 Pages 1676-1684
    Published: 1978
    Released: April 19, 2006
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    The selective formation of HD and solute radicals in the radiolysis of n-C10D22 doped with n-C10H22 at 77 K is explained quantitatively by the mechanism of a selective hydrogen-atom-abstraction reaction by D atoms. The selective hydrogen-atom abstraction by H atoms is found also in tetramethylsilane and xenon matrices as well as in the alkane matrix. The rate constants of the abstraction reaction by H atoms are compared with the bond energies of the solvent and solute molecules. The bond energy of the solvent molecule is always higher than that of the solute molecule. Even if the difference in the bond energy between the solvent and the solute is very small, the k(solute)/k(solvent) ratio is quite large. The k(solute)/k(neo-C5H12) ratios for different solutes in a neopentane matrix are not influenced by the differences in the bond energy among the solutes. Since an isotope effect on the selective hydrogen-atom abstraction reaction is small, the effect may diminish the possibility of the quantum mechanical tunneling abstraction by thermal H atoms. The energy loss of hot H atoms in a Xe matrix is discussed.
  • Katsuomi Takehira, Takashi Hayakawa, Toshio Ishikawa
    1978 Volume 51 Issue 6 Pages 1685-1690
    Published: 1978
    Released: April 19, 2006
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    The influence of preparative conditions on the structure and catalytic activity of V–Cr oxide catalyst for the liquid-phase oxidation of cyclohexene has been investigated. Three series of binary oxide, V–Cr-D, V–Cr-E, and V–Cr-F, were prepared from acidic, neutral, and alkaline media, respectively. The specific activity of the catalyst was found to be in the order: V–Cr-D>V–Cr-E>V–Cr-F, the catalyst prepared from acidic medium showing the highest activity. The results of structure analysis showed the formation of several chromium isopolyvanadates, i.e., chromium pyrovanadate, chromium metavanadate, and unknown phase (probably chromium polyvanadates), together with V2O5, Cr2O3, and solid solution of Cr6+ in V2O5 lattice. The formation of chromium isopolyvanadate having a higher degree of condensation of the vanadate anion was promoted by use of a more acidic medium in the catalyst preparation. The higher activity for autoxidation was obtained with the catalyst containing the more condensed isopolyvanadate. Epoxidation seems to proceed by the hydroperoxide intermediate mechanism on the active site differing from that for autoxidation.
  • K\={o}ji Kishimoto, Hiroshi Suga, Syûzô Seki
    1978 Volume 51 Issue 6 Pages 1691-1696
    Published: 1978
    Released: April 19, 2006
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    The heat capacities of the glassy crystalline, plastic crystalline, and liquid phases of CFCl2–CFCl2 were measured by an adiabatic calorimeter over a temperature range from 13 to 310 K, with a sample of 99.93% purity. The triple point was determined to be 297.91 K, the enthalpy and entropy of fusion being 3.666 kJ mol−1 and 12.30 J K−1 mol−1, respectively. Three kinds of relaxation phenomena were found during the heat capacity measurement centered at around 60, 90, and 130 K, respectively. The first was attributable to the β relaxation. The second was for primary glass transition, where overall rotation or reorientation of the molecules might be frozen. The third was analyzed by ascribing it to the freezing of conversion between the trans and the gauche conformers of the molecule. Activation enthalpy for the internal rotation and energy difference between the two conformers were determined to be 41 kJ mol−1 and (790±60) J mol−1, respectively. This experiment provides the first example in which three different freedoms of molecular motion are frozen successively at different temperatures as the crystal is cooled down. An effort to get a possible low-temperature ordered crystalline phase was partially successful by long annealing of the crystal. The extremely sluggish nature of the phase transition into the ordered phase will be related with the slow rate of the internal rotation of the molecule below the transition temperature.
  • Tooru Taga, Makoto Ohashi, Kenji Osaki
    1978 Volume 51 Issue 6 Pages 1697-1700
    Published: 1978
    Released: April 19, 2006
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    The crystal structure of calcium DL-glycerate dihydrate has been determined by the heavy atom method. The crystal is monoclinic, space group P21/c, with unit cell dimensions: a=14.40, b=7.63, c=10.40 Å, and β=98.8°. Two independent glycerate anions have different conformations. β-Hydroxy oxygen in one conformer is trans-gauche to α-carboxy carbon and α-hydroxy oxygen, while that in the other conformer is gauche-gauche. Ca–O interactions and hydrogen bonds stabilize the crystal structure. The calcium ion is bound to three glycerate anions and two water molecules, the two glycerate anions chelating the calcium ion with the α-carboxy oxygen and α-hydroxy oxygen, and third glycerate anion bonding to the calcium ion with β-hydroxy oxygen. Seven oxygens surround a calcium ion in a distorted pentagonal biprism arrangement with Ca–O distances ranging from 2.32 to 2.47 Å.
  • Wataru Inaoka, Shoji Harada, Tatsuya Yasunaga
    1978 Volume 51 Issue 6 Pages 1701-1703
    Published: 1978
    Released: April 19, 2006
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    Kinetic studies of the dimerization reaction of thionine in an aqueous solution have been performed by the laser temperature-jump method with the use of the stimulated Raman effect in high-pressure H2 gas. From the concentration dependence of the relaxation time, the formation and dissociation rate constants of the thionine dimer have been obtained. The data have been confirmed by the equilibrium constant, independently obtained spectrophotometrically. The formation rate constant of the dimer was very large, and the process was revealed to be a diffusion-controlled reaction, similar to those with other dyes.
  • Hideshi Hattori, Noriyoshi Asada, Kozo Tanabe
    1978 Volume 51 Issue 6 Pages 1704-1707
    Published: 1978
    Released: April 19, 2006
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    A maximum activity of tungsten oxide for the isomerization of 1-butene was observed when the catalyst was evacuated at 600 °C, the ratio of cis-2-butene to trans-2-butene being 1.4. The activity was lost by the addition of NH3, but not affected by the addition of CO2 or H2O. The oxidation states of tungsten oxide treated with hydrogen at 550 and 650 °C were WO2.89 and WO2, respectively. The activity of WO2.89 for the double bond isomerization of 1-butene was almost the same as that of WO3 but the activity of WO2 for the double bond and skeletal isomerization of 1-butene and the dehydration of isopropanol was higher than that of WO3 or WO2.89· The coisomerization of cis-2-butene-d0/d8 revealed that the double bond isomerization of butenes proceeds by an intermolecular hydrogen transfer mechanism. When cis-2-butene-d8 was introduced to the catalyst on which cis-2-butene-d0 had been preadsorbed, the reactant and the product containing much of H were obtained, no d0-species being observed. It was concluded that the active sites for the isomerization of butenes are protons of polymerized butene formed by the adsorption on Lewis acid sites of tungsten oxide surface and the isomerization takes place via carbenium ion intermediates.
  • Masako Yudasaka, Haruo Hosoya
    1978 Volume 51 Issue 6 Pages 1708-1713
    Published: 1978
    Released: April 19, 2006
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    Concentration dependence (1–10−4 molar fraction) of the UV absorption spectra of the binary mixtures of (i) acetone–water, (ii) acetone–ethanol, and (iii) diisobutyl ketone–ethanol systems was studied. In (i) and (ii) distinct spectral changes of three steps were observed in succession, while in (iii) gradual changes in two steps were observed. The intensities of the n→π* band of very dilute solutions for these systems are enhanced, respectively, by 40, 20, and 15 per cent. The results were interpreted as the following stepwise equilibria
    A+B\ ightleftarrowsAB, AB+B\ ightleftarrowsAB2, AB2+B\ ightleftarrowsAB3
    for (i) and (ii), while in (iii) the last step is obscured, where A and B denote, respectively, ketone and water or ethanol molecules. The structure of AB3 is discussed.
  • Toshihiro Ohnishi, Masahiro Hatakeyama, Naoto Yamamoto, Hiroshi Tsubom ...
    1978 Volume 51 Issue 6 Pages 1714-1716
    Published: 1978
    Released: April 19, 2006
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    Spectroscopic and electrical studies have been made for the mono- and multi-molecular layers of barium stearate mixed with carotene. The results of the electronic spectra have indicated that the carotene molecules lie parallel to the monolayer plane and are aggregated. The capacitances measured are expressed well as those of parallel plate capacitors. From these results, the structure of the layers containing carotene has been deduced.
  • Setsuo Kashino, Shin-ichi Kataoka, Masao Haisa
    1978 Volume 51 Issue 6 Pages 1717-1722
    Published: 1978
    Released: April 19, 2006
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    The crystal structures of pyrrolidinium p-chlorobenzoate (PYC) and pyrrolidinium p-toluate (PYT) have been determined from visually estimated Cu Kα data. The crystals of PYC are orthorhombic, space group Pbca, a=9.53(1), b=27.28(3), c=9.39(2) Å, and Z=8. Those of PYT are monoclinic, space group P21/c, a=14.66(3), b=9.00(2), c=9.44(1) Å, β=101.3(4)° and Z=4. The structures of PYC and PYT were refined by the blockdiagonal least-squares method to R values of 0.073 and 0.089 for 855 and 1277 non-zero reflections, respectively. In both PYC and PYT, the pyrrolidinium and benzoate ions are linked together by two kinds of N–H…O hydrogen bonds to form a ribbon along the twofold screw axis. The shorter hydrogen bond [N…O 2.697(7) Å for PYC, 2.674(5) Å for PYT] lies nearly perpendicular to the twofold screw axis, and the longer bond [N…O 2.730(7) Å for PYC, 2.738(5) Å for PYT] makes an angle of about 20° with the axis. The O…N…O angle is near to the regular tetrahedral angle [105.4(2)° for PYC, 107.1(2)° for PYT]. The crystals of PYG are isomorphous with those of piperidinium p-chlorobenzoate, piperidinium p-bromobenzoate, piperidinium p-toluate and pyrrolidinium p-bromobenzoate, but PYT crystallizes in a subgroup of the space group of the others because of the cooperative effects of the bulkiness of the methyl group and the ring size of the base moiety. The pyrrolidine rings in PYC and PYT take an approximate CS symmetry.
  • Hiroshi Nakanishi, Hiroshi Morita, Saburo Nagakura
    1978 Volume 51 Issue 6 Pages 1723-1729
    Published: 1978
    Released: April 19, 2006
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    Near and vacuum UV absorption spectra of trifluoroacetylacetone (TFAC) and hexafluoroacetylacetone (HFAC) were measured at room temperature in the vapor phase and in perfluorohexane in the 30000–80000 cm−1 region, together with a vacuum UV absorption spectrum of acetylacetone in the 60000–80000 cm−1 region. By the aid of the modified CNDO-CI calculation, each of the observed valence-shell transition bands was assigned to the π–π**, π–σ*, or σ–σ* transition. The third σ–σ* bands observed at 65200 cm−1 for acetylacetone, at 78000 cm−1 for TFAC, and at 70400 cm−1 for HFAC were concluded to be rich in the CT character pertinent to hydrogen bond. In particular, the third σ–σ* band of HFAC was found to be the CT band pertinent to hydrogen bonding in the sense that the contribution of the CT configuration to the excited state amounts to 67.4%.
  • Yukio Zenitani, Haruo Tokunan, Yasushi Kai, Noritake Yasuoka, Nobutami ...
    1978 Volume 51 Issue 6 Pages 1730-1735
    Published: 1978
    Released: April 19, 2006
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    The molecular structure of oxydi(carboxymethyl)bis(triphenylphosphine)palladium(II), [Pd(C4H4O3)(PPh3)2] has been determined by means of X-ray diffraction. The crystal belongs to the orthorhombic system, space group P212121, with four formula units in a cell with dimensions of a=16.320(2), b=20.104(2), and c=10.271(2) Å. R=0.058 for 4732 non-zero relfections. The feature of the structure is that the palladium atom is chelated by an acetic anhydride to form a six-membered ring [Pd–C=2.141(13) and 2.124(11) Å], and the palladium atom has a square-planar geometry.
  • Tsuguo Sawada, Takeshi Shibamoto, Hitoshi Kamada
    1978 Volume 51 Issue 6 Pages 1736-1738
    Published: 1978
    Released: April 19, 2006
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    Fluorescence lifetimes of morin complexes of Be(II), Zn(II), Al(III), Ga(III), In(III), Th(IV), Zr(IV), and Sn(IV) extracted into isopentyl alcohol from the acid solution at various pH values were investigated. The result indicates that the Al(III), Ga(III), and In(III) complexes change their compositions according to the change of pH. More detailed investigations by the use of mole ratio method suggest that Al(III), Ga(III), and In(III) form complexes having two different mole ratios of 1 to 1 and 1 to 2 (metal ion: morin). Fluorescence lifetimes were changed according to the changes of the composition of the complex and the differences of the metal ion.
  • Shoji Kaneko, Fumio Imoto
    1978 Volume 51 Issue 6 Pages 1739-1742
    Published: 1978
    Released: April 19, 2006
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    The phase relation of products obtained by the reaction between PbO and TiO2 under hydrothermal conditions up to 500 °C and 500 kg/cm2 for 5h has been investigated. The yield and crystallographic properties of purified PbTiO3 depend upon the PbO/TiO2 mole ratio (Pb/Ti ratio) in raw mixtures as well as the reaction temperature. Both PbTiO3 and PbTi3O7 are synthesized at a remarkably low temperature under hydrothermal conditions, as compared with the ignition process in air. Pure and well-crystallized PbTiO3 is obtained by heat-treating above 400 °C at Pb/Ti ratios greater than 1.0 and by dissolving excess PbO with acetic acid. PbTi3O7 coexists occasionally with PbTiO3 to some extent at Pb/Ti ratios less than 1.0, but appears as a single phase in the temperature range 100–450 °C at the Pb/Ti ratio 0.33. The unit cell volume of PbTiO3 prepared at lower temperature is considerably large, suggesting a loosely-packed structure. The compound is always of tetragonal form containing no metastable cubic form.
  • Katsura Mochizuki, Taira Imamura, Tasuku Ito, Masatoshi Fujimoto
    1978 Volume 51 Issue 6 Pages 1743-1750
    Published: 1978
    Released: April 19, 2006
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    The reactions of Co2+ with 4-(2-pyridylazo)resorcinol (PAR), 1-(2-pyridylazo)-2-naphthol (PAN), and their thiazolyl analogs TAR and TAN in aqueous or aqueous dioxane media are followed by a rapid-scan spectroscopic method combined with stopped-flow technique. The step of the fast formation of cobalt(II) complexes is clearly discriminated from the subsequent slower step of oxidation to the cobalt(III) state. Formation and redissolution of transient insoluble intermediates are observed in the stopped-flow signals for the light scattered by the reaction mixture. The metal-to-ligand ratio in the short-lived intermediate cobalt(II) complex of PAR and PAN is determined to be 1 : 2 by applying the method of continuous variation to the fast change in stopped-flow signals. The rate constants k1 and k2 for the step of formation of 1 : 1 cobalt(II) complex with the species LHH* and LH of PAR in aqueous solution and with the species LH2+ and LH of PAN in 5%(v/v) dioxane-water are determined to be k1=4.8×104 and k2=9.8×104 dm3 mol−1 s−1, and k1<103 and k2=4.6×103 dm3 mol−1 s−1, respectively.
  • Ryoei Ishida, Hifumi Narita, Koichi Tonosaki
    1978 Volume 51 Issue 6 Pages 1751-1754
    Published: 1978
    Released: April 19, 2006
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    Copper(II) ion reacted with 2,2′-bipyridine (bpy) and Eriochrome Cyanine R (ECR) to give one of two kinds of ternary complexes according to the amount of reagents in a weakly basic medium. The combining ratios of three components in the complexes were estimated to be Cu(II): bpy: ECR= 1 : 1 : 2 and 1 : 1 : 1, respectively, the former having an absorption maximum at 515 nm and the latter at 550 nm. The color development of the 1 : 1 : 2 complex was utilized in the spectrophotometric determination of copper(II) at microgram level. The ternary complex gave a maximum absorbance at 515 nm in the pH range 10.2–10.6. Under optimum pH, 2,2′-bipyridine and Eriochrome Cyanine R concentrations, a linear relationship holds between the absorbance of the complex and copper(II) concentration up to 6×10−5 mol dm−3. The apparent molar absorption coefficient at 515 nm is about 20400 dm3 mol−1 cm−1, corresponding to Sandell’s sensitivity index of 0.0031 μg cm−2.
  • Toshiro Aratani, Kiyochika Yahikozawa, Hitoshi Matoba, Shigeki Yasuhar ...
    1978 Volume 51 Issue 6 Pages 1755-1760
    Published: 1978
    Released: April 19, 2006
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    A new chemical precipitation process utilizing CaSx solution as a single coagulant was tested for the removal of heavy metals from a batch stirred vessel. The precipitation of heavy metals from the simulated wastewater was investigated under varing conditions of pH, temperature, and heavy metal concentrations. Several agitating speeds were studied for the gases (atmospheric air and CO2 gas) blown into the water to decompose the coagulant (CaSx). The findings are as follows: Heavy metal removal in keeping with the water quality standards in Japan was achieved for the simulated wastewater having pH’s between 3 and 11, and the temperatures from 10 to 85 °C. The agitating speed for optimum removal was found to be 10 Hz. More than 250 ppm of the initial heavy metal concentration gives sufficient removal at stoichiometric quantities of coagulant, while less than 50 ppm of the initial concentration results in rather poor removal owing to the colloidal properties of the metal sulfide or hydroxide. For low concentrations of heavy metals, several units of the coagulant over stoichiometric amount are necessary for sufficient precipitation to achieve the water quality standards.
  • Kozo Nagashima, Masataka Ogino, Izumi Nakai
    1978 Volume 51 Issue 6 Pages 1761-1763
    Published: 1978
    Released: April 19, 2006
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    Single crystals of a recently described metal oxide sulfide mineral sarabauite and three related oxide-sulfides of alkaline earths and antimony were hydrothermally synthesized. (1) CaSb10O10S6: color, carmine red; crystal system, monoclinic; space group, C2/c. (2) Compound in Sr–Sb–O–S system (O<S), blackish silver, monoclinic, P21/a. (3) Compound in Ba-S–b–O–S system (O>S), reddish orange, triclinic P1 or P\bar1. (4) Compound in Ba–Sb–S–O system (O<S), blackish brown, monoclinic, P21/a.
  • Hideo Suzuki, Toshio Takiguchi, Yoshikane Kawasaki
    1978 Volume 51 Issue 6 Pages 1764-1767
    Published: 1978
    Released: April 19, 2006
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    Several acetato and dithiocarbamate complexes of bis(cyclopentadienyl)zirconium(IV), Cp2Zr(X)OAc (X= Me, Cl, OAc), Cp2Zr(X)dmtc (X=Me, Cl; dmtc=S2CNMe2), and Cp2Zr(X)detc (X=Me, Cl; detc=S2CNEt2) have been prepared. Infrared, 1H NMR and mass spectra of these complexes suggest the chelation of acetato (except for one acetato group in Cp2Zr(OAc)2) and dithiocarbamate groups, affording 18-electron configuration of the zirconium atom. The infrared spectrum of diacetate bis(cyclopentadienyl)zirconium(IV) shows that one acetato group acts as bidentate ligand and the other as unidentate. Remarkable benzene- and hexafluorobenzeneinduced shifts were observed in the 1H NMR signal of methyl group attached to the zirconium atom and the dithiocarbamate group.
  • Eiichi Miki, Hiromichi Okamura, Kunihiko Mizumachi, Tatsujiro Ishimori
    1978 Volume 51 Issue 6 Pages 1768-1770
    Published: 1978
    Released: April 19, 2006
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    [Co(C9H8N2)2NO]X2·nH2O (C9H8N2=8-aminoquinoline; X=Cl, Br, I, NO3, ClO4, and SO4/2; n=0, 1, 1.5, and 2) was isolated by the reaction of nitrogen oxide with a mixture of the corresponding cobalt(II) salt and 8-aminoquinoline in methanol. The IR, UV, and molar conductivity measurements suggest that the geometry of the cation is a tetragonal pyramid with an apical NO.
  • Fujio Izumi
    1978 Volume 51 Issue 6 Pages 1771-1776
    Published: 1978
    Released: April 19, 2006
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    Titanic acid was treated with hydrochloric, nitric, sulfuric, and hydrofluoric acids at 350 °C and 49 MPa to give titanium(IV) oxide. With increasing acid concentration, its polymorphic forms changed from anatase to rutile in hydrochloric and nitric acids, but from anatase to rutile, then back to anatase in sulfuric and hydrofluoric acids. Rutile and anatase crystals were grown from 1.7–9.5 mol dm−3 hydrofluoric acid at 360–560 °C by the temperature-drop method. Lower temperatures and higher concentrations of the acid favored anatase formation. The mechanisms for crystallization of the two forms are discussed by considering the chemical behavior of titanium(IV) complexes involved in their primary nucleation.
  • Hiroshi Nakanishi, Osamu Yamamoto
    1978 Volume 51 Issue 6 Pages 1777-1783
    Published: 1978
    Released: April 19, 2006
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    9-Ethyl-1,4-dimethoxytriptycene, 1,5-dichloro-9-ethyltriptycene, and 9-ethyl-1,4-dimethyltriptycene were prepared. The 13C NMR spectra of these compounds were measured at low temperatures in order to obtain information about the restricted rotation of the ethyl group. It was found that the former two compounds have the meso isomer as well as the dl isomer. Different chemical shifts of the methylene carbons in the ethyl group, C(2) and C(3) of the benzene A ring, and some quaternary carbons in the two isomers of 9-ethyl-1,4-dimethoxytriptycene indicate that the 120°C rotation around Csp3–Csp3 single bond in the ethyl group deforms the benzene or bicyclo[2.2.2]octatriene skeleton. The complete line-shape analyses of the temperature-dependent 13C NMR spectra of this compound were performed, and the thermodynamic static parameters and activation parameters of the ethyl rotation were determined. The correlation between the rotational barriers of the alkyl groups and their bulkiness was briefly discussed.
  • Makoto Kaneta, Hiroshi Hikichi, Seiichi Endo, Noboru Sugiyama
    1978 Volume 51 Issue 6 Pages 1784-1787
    Published: 1978
    Released: April 19, 2006
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    Six analogous new flavones with a skeleton similar to arthraxin, which is a light-stable, natural, new flavone, have been synthesized by the use of a modification of Allan-Robinson’s flavone synthesis. The structures of these compounds were elucidated by means of the Gibbs reaction, NMR, and mass spectrometry. The light resistance of these flavones was then examined by means of UV spectrometry. The results indicate that these flavones, with a 4H, 10H-benzo[1,2-b : 3,4-b′] dipyran-4,10-dione skeleton, in contrast with natural common flavonol and arthraxin, show a high resistance to light.
  • Jun-ichi Aihara
    1978 Volume 51 Issue 6 Pages 1788-1792
    Published: 1978
    Released: April 19, 2006
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    The resonance energies of conjugated compounds in the electronically excited state were calculated on the basis of the aromaticity theory previously reported by us. The allowednesses of pericyclic reactions were predicted by means of these resonance energies. The predictions based on the resonance energy difference (RED) between the pericyclic transition state and the reactant(s) are in general agreement with the experiment.
  • Haruo Inoue, Mitsuhiko Hida
    1978 Volume 51 Issue 6 Pages 1793-1798
    Published: 1978
    Released: April 19, 2006
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    The bromine atom at the 4 position of 1-amino-2,4-dibromoanthraquinone (1) was substituted by butylamine and aniline by the irradiation of visible light. In ethanol the dissolved oxygen promoted the reaction and anthracene, a triplet quencher, had little effect. In benzene, the dissolved oxygen retarded the reaction and anthracene had a considerable quenching effect. Kinetic analysis indicated that in ethanol the photoamination of 1 proceeds mainly through the interaction of 1 in S1(1CT) with the ground state oxygen, while in benzene it does through the T1(3CT) of 1 without the aid of oxygen. The detailed reaction mechanism in benzene has been discussed and the rate constant of each process including the deactivation constant of the upper excited T2(3*) level evaluated.
  • Shinichi Ueji
    1978 Volume 51 Issue 6 Pages 1799-1804
    Published: 1978
    Released: April 19, 2006
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    The effects of solvents on the intramolecular OH…π and OH…O hydrogen bonding in 2-arylphenols and 2,6-diarylphenols have been studied by examining the OH stretching IR absorption spectra in a range of solvents. The solvent shifts of the hydrogen bonded bands, νOH…π and νOH…O, followed the G correlation and the BHW plot. The success of both correlations suggests that the solvent shifts are primarily due to a specific solvent-solute association, even in relatively non-polar solvents. The solvent sensitivity of the OH…π and OH…O hydrogen bonded bands depended on the stereo-chemical environment around the hydrogen bonded system rather than on such electronic factors as the strength of the hydrogen bonding. On the basis of the relationship between the solvent sensitivity and the structural changes over a group of phenols, a simplified model for the solvent-solute association is put forward. Furthermore, this simplified model is also discussed in terms of the aromatic solvent-induced shifts in the PMR spectra.
  • Kiyoshi Hasegawa, Syuzi Hirooka, Hiroshi Kawahara, Akihiko Nakayama, K ...
    1978 Volume 51 Issue 6 Pages 1805-1810
    Published: 1978
    Released: April 19, 2006
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    The syntheses of new heterocyclic compounds by the reaction of 2-arylacetylene-1-sulfonamides 1, (Z)-β-bromo- 12 or (Z)-α-chloro-β-styrenesulfonamides 13 with heterocumulenes are described. Weak base treatment of ureas R1C6H4C≡CSO2NHC(=O)NHR2 prepared from 1 and isocyanates gave 2-amino-6-aryl-1,4,3-oxathiazine 4,4-dioxides, whereas strong base treatment of the ureas afforded 3-oxo-4,5-diphenyl-2,3-dihydro-1,2,4-thiadiazine 1,1-dioxides where R2 is a phenyl group. The thiadiazines were also prepared by the strong base treatment of N-((Z)-α-bromo- or (Z)-β-chlorostyrylsulfonyl)-N′-phenylureas. The reaction of 1,12, or 13 with isothiocyanates in the presence of weak base gave 3-amino-5-aryl-1,4,2-dithiazine 1,1-dioxides, but the major products produced were 3-amino-5-benzylidene-1,4,2-dithiazole 1,1-dioxides when 12a was treated with isothiocyanates in the presence of strong base. The reaction of 1 with carbon disulfide and dimethyl sulfate in the presence of 5 M NaOH afforded 3-methylthio-5-benzylidene-1,4,2-dithiazole 1,1-dioxide with a small amount of 3-methylthio-5-aryl-1,4,2-dithiazine 1,1-dioxide. A mixture of both isomers was also prepared from 12a. Possible mechanisms for the formation of the heterocycles from 1, 12, or 13 are suggested.
  • Tetsuro Majima, Chyongjin Pac, Hiroshi Sakurai
    1978 Volume 51 Issue 6 Pages 1811-1817
    Published: 1978
    Released: April 19, 2006
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    Pyridine, methylated pyridines, and methylated imidazoles quenched the exciplexes of aromatic nitrile–2,5-dimethylfuran or 2,5-dimethyl-2,4-hexadiene, and the rate constants for the exciplex quenching were obtained. The exciplex quenching by 2-methyl- and 2,6-dimethylpyridines was much less efficient than that by the other quenchers. The exciplex quenching was discussed in terms of the interaction of the n-orbital of the quenchers with the positive charge developed on the electron-donor side of the exciplexes. Curved Stern-Volmer plots were obtained in the quenching of aromatic nitrile fluorescence by 1-methylimidazole and/or 1,2-dimethylimidazole. On the basis of the kinetic results, the mechanism was discussed in terms of a termolecular interaction between excited singlet aromatic nitrile, the methylated imidazole as the π-donor, and the second one as the n-donor.
  • Sakae Uemura, Nanao Watanabe, Akio Toshimitsu, Masaya Okano
    1978 Volume 51 Issue 6 Pages 1818-1820
    Published: 1978
    Released: April 19, 2006
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    The reactions of alkyl halides with mercury(II) and potassium thioacetates afford alkyl thioacetates (RSCOMe), SN1 and SN2 type reactions taking place. In neither case is ROCS Me formed. Reactions with mercury(II) selenocyanate usually give only small amounts of alkyl selenocyanates and/or isoselenocyanates as isolated products except the case of benzyl bromide from which benzyl selenocyanate was obtained almost quantitatively. The ambident reactivity of this salt was revealed to be not so strong as that of mercury(II) thiocyanate. The reaction with potassium selenocyanate is also reported for comparison.
  • Yasuo Wada, Takeshi Yamazaki, Kazuo Nishiura, Shigeo Tanimoto, Masaya ...
    1978 Volume 51 Issue 6 Pages 1821-1825
    Published: 1978
    Released: April 19, 2006
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    The Lewis acid-catalyzed reactions of olefins with chloromethoxymethane (CM) or dimethoxymethane (DM) and aliphatic or aromatic nitriles afforded the 1 : 1 : 1 adducts and/or their hydrolysis products in various yields, together with the 1 : 1 olefin–CM (or DM) adducts. AlCl3, FeCl3, ZnCl2, and SnCl4 were effective catalysts for the reaction with CM, whereas BF3 and SnCl4 were effective for that with DM. In the case of cyclohexene, the addition proceeded in the trans-manner; i.e., the methoxymethyl group and the nitrile molecule were added to the olefin from opposite sides.
  • Tetsuo Suami, Toshiki Otake, Shigeru Nishiyama, Ryoichi Adachi, Katsum ...
    1978 Volume 51 Issue 6 Pages 1826-1829
    Published: 1978
    Released: April 19, 2006
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    Condensation of 1′,2,2″,3,3′,3″,4,4′,4″,6′-deca-O-acetylraffinose (1) with 2,3,4,6-tetra-O-benzyl-D-galactopyranosyl chloride in the presence of tetraethylammonium chloride, followed by deacetylation, debenzylation and subsequent acetylation afforded stachyose tetradecaacetate. An isomer in which a terminal D-galctopyranosyl group is attached to the 6″-O of raffinose in β-anomeric linkage, was prepared by condensing 1 with 2,3,4,6-tetra-O-acetyl-α-D-galactopyranosyl bromide in the presence of mercury(II) cyanide. 13C NMR spectra of stachyose tetradecaacetate and the isomer were discussed.
  • Kazuki Sato, Kazuo Ueda, Michio Kondo, Haruhiko Aoyagi, Nobuo Izumiya
    1978 Volume 51 Issue 6 Pages 1830-1834
    Published: 1978
    Released: April 19, 2006
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    To investigate the importance of the orientation of side chains of amino acid residues in gramicidin S (GS) for the antibacterial activity, a dimerized analog of GS, namely S,S′-bi([1-L-hemicystine]-GS) (13) was synthesized via removal of p-methoxybenzyl group of [1-S-p-methoxybenzyl-L-cysteine]-GS (12) and subsequent oxidation. Compound 12 showed the same antibacterial activity as GS, whereas 13 was inactive. The resemblance of ORD curves of the two analogs to that of GS suggested the similarity of peptide-backbone structure of these three compounds. Strong activity of 12 was explained by similar conformation of 12 to that of GS. To explain the inactivity of 13, a molecular model was proposed; four hydrophilic side chains are located on surface of the molecule, whereas six hydrophobic are burried.
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