Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 54 , Issue 5
Showing 1-50 articles out of 64 articles from the selected issue
  • Ryuichi Minami, Takashi Okada
    1981 Volume 54 Issue 5 Pages 1283-1287
    Published: 1981
    Released: June 02, 2006
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    A new Monte Carlo trajectory method is proposed to estimate the rate constants of elementary molecular reactions. In this study, we have introduced the conditional Monte Carlo technique and obtained the following advantages. First, the procedure of calculation has been simplified. That is, the trajectory data have been accumulated as only one data set, from which the rate constants at any temperature have been reduced easily. Secondly, the necessary number of trajectories has been decreased by employing appropriate conditional distribution functions. Lastly, the error estimation has become possible on a reasonable base. This method has been applied to the (H2, H2) direct exchange reaction as an example and the result is reported briefly.
  • Tohr Yamanaka, Takashi Imai
    1981 Volume 54 Issue 5 Pages 1288-1292
    Published: 1981
    Released: June 02, 2006
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    On the acetylation of mesitylene (1, 0.5–1 mol dm−3) with acetic anhydride (Ac2O, 0.5–1.5 mol dm−3) at 30–90 °C in acetic acid as solvent, SbCl5, FeCl3, SnCl4, or ZnCl2 (each of 0.02–0.2 mol dm−3) under the co-catalytic effect of HCl (0–0.75 mol dm−3) showed a continuous catalytic activity. The product was exclusively 2′,4′,6′-trimethylacetophenone for conversions of 1 in the range of 0–90%. The reaction was first order with respect to 1 and Ac2O. The rate constants were proportional to 1–1.4th power of the concentration of the metal chloride. The apparent activation energy was 18.8 kcal mol−1 for all the catalysts. The catalytically active species are thought to be the conjugate acids from the metal chloride and HCl. Relative catalytic activities of the metal chlorides varied in parallel with their relative Lewis acid-strengths.
  • Hidetsugu Tanaka, Yoshihiro Osamura, Toshio Matsushita, Kichisuke Nish ...
    1981 Volume 54 Issue 5 Pages 1293-1298
    Published: 1981
    Released: June 02, 2006
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    The reaction mechanism of photoisomerization of isoxazoles and the wavelength dependent photochemistry of azirine intermediates which are the photoisomerization reaction intermediates are investigated theoretically by means of ab initio MO-CI calculation. The present calculation shows that the lowest excited singlet state, S1, of azirine intermediate is an (n→π*) state localized at the carbonyl chromophore, while the S2 state is assigned to be an (n→π*) state localized at the ketimine chromophore. Intersystem crossing from S1 to T1 states of azirine intermediate causes the N-C bond rupture of azirine ring and leads to isoxazole. On the other hand, azirine intermediate in the S2 state proceeds to the C-C bond break of azirine ring and converts to oxazole via intersystem crossing to the T1 state.
  • Masamoto Iwaizumi, Yoshimasa Fukazawa, Nobuo Kato, Shô Itô
    1981 Volume 54 Issue 5 Pages 1299-1304
    Published: 1981
    Released: June 02, 2006
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    The anion radicals of syn- and anti-[2.2](2,6)azulenophane, (1) and (2), [2.2](1,3)azulenophane, (3), and [2](1,3)-azuleno[2]paracyclophane, (4), all produced by alkali metal reduction in various solvents, have been investigated by ESR and ENDOR spectroscopy. They exist in the ion pair with cations in the solutions, except for 4\ ewdot which exists in 1,2-dimethoxyethane with Na+. Their ion pairing tendency is appreciably higher than that of the naphthalenophane anion radicals. The unpaired electron in these ion pairs localizes mostly on an azulene ring (in 1\ ewdot, 2\ ewdot, and 3\ ewdot, close to a cation). The polarization effects due to the pairing with the cations are much larger than those in the naphthalenophane anion radicals, and increase in the order 1\ ewdot2\ ewdot3\ ewdot, indicating that the smaller the inter-layer orbital overlap, the larger the polarizability. The unpaired electron of 4\ ewdot localizes mostly on the azulene ring even in the free anion.
  • Fujio Takahashi, Tetuo Komori
    1981 Volume 54 Issue 5 Pages 1305-1307
    Published: 1981
    Released: June 02, 2006
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    A sandwich-type photocell was made by placing an electrolyte between two electrodes. A transparent electrode, a glass plate coated with In2O3, was used for one electrode. A mixture of chlorophyll and 2-(cis-10-heptadecenyl)-6-methoxy-p-benzoquinone was spread onto this transparent electrode. A Pt plate covered by chlorophyll or a mixture of chlorophyll and riboflavin tetrabutyrate was used as the other electrode. The electrolyte contained flavin mononucleotide in a phosphate buffer. The potential difference between the two electrodes was 314 mV and the maximum photovoltage under illumination was 176 mV. The photocell is compact and can produce a photocurrent for more than 90 h.
  • Hiroshi Yoneyama, Hisashi Shiota, Hideo Tamura
    1981 Volume 54 Issue 5 Pages 1308-1313
    Published: 1981
    Released: June 02, 2006
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    Heterogeneous reactions of nitrogen monoxide on illuminated TiO2 catalysts in 1 mol dm−3 HClO4 were studied by electrochemical analysis. Nitrogen monoxide was reduced to ammonia and hydrazine. The main reaction was found to be a chemical reaction of hydroxylamine as a reaction intermediate with nitrogen monoxide to give molecular nitrogen. Nitrate was detected as an oxidation product formed by the counterpart reaction of the reduction of nitrogen monoxide.
  • Norio Ohtomo, Kiyoshi Arakawa, Makoto Takeuchi, Toshio Yamaguchi, Hito ...
    1981 Volume 54 Issue 5 Pages 1314-1319
    Published: 1981
    Released: June 02, 2006
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    The structure factors Sm(Q) over a wide range of Q(1.7–25 Å−1) for aqueous solutions of DC1 and DBr (ca. 1 M) at room temperature have been determined by means of LINAC-TOF neutron diffraction. The intramolecular structures of D2O and D3O+ in the solutions are found to be identical with those in the “revised watery model” for water. Applying the subtraction method of analysis to diffraction data for the solutions, we have obtained the following results with respect to the structure of the nearest hydration shell around ions in the DCl and DBr solutions: (a) D3O+ is tetrahedrally coordinated with four water molecules and Cl and Br are octa-hedrally coordinated with six ones, (b) the O–O distances between the central oxygen atom and that of hydrated water molecules for D3O+ are 2.88±0.05 Å, (c) the anion-oxygen distances are 3.10±0.05 Å for Cl and 3.21±0.05 Å for Br, and (d) around cations (D3O+) water molecules take the configuration to orient the axis of one of the two lone-pair hybrids on a straight line joining an oxygen atom and the cation, while around anions (Cl and Br) those take the configuration to orient the vector which bisects the D–O–D angle on a straight line joining an oxygen atom and the cation.
  • Ryuichi Minami, Koichi Itoh, Hiroshi Sato, Hiroaki Takahashi, Keniti H ...
    1981 Volume 54 Issue 5 Pages 1320-1323
    Published: 1981
    Released: June 02, 2006
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    The dielectric relaxation mechanism of primary alcohols in solutions of various solvents with and without a hydrogen-bonding capacity was theoretically studied using the concept of the chemical equilibrium between hydrogen-bonded chain multimers and that between the multimers and solvents. The dipole-inversion processes originating from the successive rotation of the hydroxyl groups of the hydrogen-bonded multimers were considered to play the dominant role in the dielectric relaxation of alcohol solutions. By applying the one-dimensional random-walk process to the dipole inversion, we estimated the effect of dilution upon the dielectric relaxation times of primary alcohol in solution. The results of our calculation appear to explain the experimental data.
  • Kazuo Nomura, Akira Matsubara, Hideo Kimizuka
    1981 Volume 54 Issue 5 Pages 1324-1331
    Published: 1981
    Released: June 02, 2006
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    A theory for the ion transport across liquid ion-exchange membrane was presented on the basis of nonequilibrium thermodynamics with the assumptions that the carrier ions and complexes were present only in the membrane phase, and that there was no volume flow and all chemical reactions were at equilibrium. The equations for “total” fluxes of membrane-permeable ions at steady state were derived from a set of the equations for “individual” fluxes of all mobile species present in the liquid membrane where the complexes were assumed to be partially dissociated. The “total” phenomenological coefficients were able to be expressed in terms of the “individual” coefficients. The diffusional and electroconductional membrane permeabilities to a selective ion in the liquid membrane–single electrolyte system were found to be in the same form as those in the fixed-site membrane–single electrolyte system, if the mean diffusion coefficient and mean mobility of the free species and its complex were used. The rate constants in the permeation process were also related to the diffusional membrane permeability. The experimental examination was made on a liquid cation-exchange membrane–aqueous single electrolyte system at 25 °C. The solution of calcium hexadecyl sulfate in 1-octanol and calcium chloride were used as the liquid membrane and the electrolyte, respectively. All the measured quantities were consistently interpreted by the presented theory.
  • Masakazu Iwamoto, Tsuneyasu Hashimoto, Toshikazu Hamano, Shuichi Kagaw ...
    1981 Volume 54 Issue 5 Pages 1332-1337
    Published: 1981
    Released: June 02, 2006
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    The reduction of Ag+ ions in X zeolites by hydrogen, the reoxidation of Ag atoms by oxygen, and the formation of silver particles were studied kinetically. The reduction is suggested to be a catalyzed reaction requiring an activation of hydrogen at some specific sites on the basis of the influence of exchange levels and hydrogen pressures on the reduction rates. At elevated temperatures the reduction of Ag+ ions proceeded quantitatively and resulted in formations of Ag particles with a diameter between 10 and 25 nm and of highly dispersed Ag clusters. The clusters were easy to be reoxidized by oxygen at 473 K or below, while the particles were difficult to revert into the zeolite matrix. The diameter of the Ag particles was dependent on the reduction temperature and ion-exchange level and independent on the reduction time. It is discussed that this is due to the slow nucleation and the fast nuclear growth of Ag particles.
  • Noriaki Hirayama, Keiichi Takahashi, Kunikatsu Shirahata, Yuji Ohashi, ...
    1981 Volume 54 Issue 5 Pages 1338-1342
    Published: 1981
    Released: June 02, 2006
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    The structure of gilvocarcin M, C26H26O9, an antibiotic with a novel carbon skeleton, has been determined by single crystal X-ray analysis. The space group is P21 with a=15.063(5), b=16.162(4), c=4.905(2) Å, β=91.47(3)°, and Z=2. The structure was solved by direct methods, and least-squares refinement using 1734 reflexions gave the final R value of 0.054. The title compound is composed of a unique aglycone and a fucofuranose, which are linked together through a C–C glycosyl linkage. The furanose ring takes the °E conformation.
  • Katsunosuke Machida, Yoshihiro Kuroda
    1981 Volume 54 Issue 5 Pages 1343-1347
    Published: 1981
    Released: June 02, 2006
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    A general method of the crystal packing optimization is developed for the molecular crystals consisting of non-rigid molecules. The intramolecular potential is described as a general harmonic force field in terms of a suitable set of internal symmetry coordinates, and the intermolecular potential as a sum of the pairwise atom-atom interaction terms. The adjustable structure parameters are those among the six cell constants, a, b, c, α, β, and γ, and the translations and the rotations of the molecules which maintain the crystal symmetry. The intermolecular force is separated into two parts, one of which determines the location of the center of mass and the orientation of the principal axes of each molecule and the other leads to a certain molecular distortion. The calculated distortion may be used, in addition to the difference between the calculated and the observed crystal structures, as a check point of the reliability of the model potential. The importance of this separation in the rigid molecule approximation is pointed out.
  • Katsunosuke Machida, Akira Kagayama, Yoshihiro Kuroda
    1981 Volume 54 Issue 5 Pages 1348-1353
    Published: 1981
    Released: June 02, 2006
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    The lattice energies, the deviations of the structure parameters from the model equilibrium, the molecular distortions due to the intermolecular interaction and the vibrational frequencies of α-glycine, L-alanine and DL-alanine crystals were calculated from three sets of parameters for the pairwise atom-atom interaction potential functions. By comparing the calculated quantities with the observed ones, the combination of the exp-6 type non-bonded potential and the Lippincott type hydrogen bond stretching potential is shown to afford a better model of the intermolecular interaction in these crystals than the combination of the Lennard-Jones 6-12 potential and the general hydrogen bond 10-12 potential.
  • Takashi Kakiuchi, Mitsugi Senda
    1981 Volume 54 Issue 5 Pages 1354-1359
    Published: 1981
    Released: June 02, 2006
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    The adsorption of glycine, DL-serine, L-threonine, L-asparagine, L-glutamine, L-valine, L-leucine, L-methionine, and L-tryptophan at the mercury-aqueous sodium fluoride solution interface has been studied by measuring differential capacities, potentials of zero charge, pzc, and surface tensions at the pzc. The standard adsorption free energies for these amino acids and for the amino acids previously studied have been used to deduce hydrophobicity scales of amino acid side chains at positively charged, negatively charged, and uncharged interfaces. The hydrophobicity scale at the uncharged interface was basically similar to that of Nozaki and Tanford. When the surface was charged positively, the positions of serine and alanine, and of threonine and α-aminobutyric acid, in the scale were reversed. This reversion was primarily ascribed to the difference in the positions of maximum adsorption potentials between the amino acids with an aliphatic side chain and those with a hydroxyl group in the side chain.
  • Sachiko Sakura, Rauno Virtanen
    1981 Volume 54 Issue 5 Pages 1360-1363
    Published: 1981
    Released: June 02, 2006
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    Iron(III) interferes with the operation of a cadmium, lead and copper ion-selective electrode. The cadmium ion-selective electrode (CdS/Ag2S) showed a potential shift to the positive direction of more than 100 mV for a decade change of iron(III) concentration. However, the exact mechanism for this interference is not known, though it is expected to be the oxidation of sulfide ion by Fe(III). The mechanism of interference by iron(III) was studied by using the cadmium ion-selective electrode, flow-through cell, pH buffer solutions, potentiometric titrations, and atomic absorption spectrophotometry measurements. It was found that iron(III) promotes dissolution reaction of cadmium ions from the solid cadmium sulfide electrode and that flow conditions of samples have no effect on the iron(III) interference.
  • Akinori Isozaki, Naoki Soeda, Satori Utsumi
    1981 Volume 54 Issue 5 Pages 1364-1367
    Published: 1981
    Released: June 02, 2006
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    A new and simple method for the determination of ppb levels of copper by electrothermal atomic absorption spectrometry was established. The main feature of the proposed method is that chelating resin, a preconcentration agent for copper, is introduced directly as a “resin-suspension” into the carbon tube atomizer without drying and weighing of the resin. To a 250 cm3 sample solution containing up to 1.0 μg of copper, 0.10 g of chelating resin (below 400 mesh) is added, and the mixture is stirred for about 20 min. After the separation of the resin from the aqueous phase through a membrane filter, 5.0 cm3 of resin-suspension is prepared by adding water to the resin. Then, 10 μdm3 (resin: 0.2 mg) of the suspension is introduced into an atomizer, and the copper peak-height is measured under the optimum operating conditions. The calibration graph was linear over the concentration range from 0.1 ppb to 4.0 ppb of copper. The relative standard deviation was 2.3% from 10 repeated measurements; a mean value of 1.08 ppb copper was obtained for a sea water sample.
  • Ryohei Amano, Akiko Sato, Shin Suzuki
    1981 Volume 54 Issue 5 Pages 1368-1374
    Published: 1981
    Released: June 02, 2006
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    Two fundamental experiments (to determine vapor pressures and vacuum sublimation-recrystallizing temperature zones) were undertaken on a series of remarkably volatile and thermally stable lanthanoid(III) chelates of 2,2,6,6-tetramethyl-3,5-heptanedione (Ln(thd)3) in order to obtain information about their sublimation behavior. Vapor pressures of these chelates were measured from 100 to 150 °C by means of a modified Knudsen effusion technique. Vacuum sublimation-recrystallizing temperatures were determined by using a sublimation apparatus with a continuous temperature gradient along its sublimation tube. The obtained enthalpies of sublimation were classified into three groups (La to Gd, Tb and Dy, and Ho to Lu), and the vacuum sublimation-recrystallizing temperature zones were divided into two sets (La to Tb, and Dy to Lu). The Tb and Dy chelates were also found to change thermally from a dimeric form to a monomeric form at a definite temperature. These results are explained in terms of the two different crystallizing forms of Ln(thd)3 chelates. Furthermore, the regularity in their sublimation behavior is discussed as a function of the atomic numbers of the lanthanoid metals, using thermochemical considerations.
  • Sei’ichiro Iijima, Ritsuko Saida, Izumi Motoyama, Hirotoshi Sano
    1981 Volume 54 Issue 5 Pages 1375-1379
    Published: 1981
    Released: June 02, 2006
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    An interesting temperature dependence of the valence state was observed in the Mössbauer spectra of the mixed-valence salts of 1′,1'″-dialkylbiferrocenes, measured at various temperatures from 4.2 K to 300 K. A mechanistic consideration of the temperature dependence has been carried out assuming a conformational change of the monocation salts induced both by the variation in the temperature and by the kind of counter anion.
  • Hideaki Fujiwara, Fumihiko Sakai, Miyoko Takeyama, Yoshio Sasaki
    1981 Volume 54 Issue 5 Pages 1380-1384
    Published: 1981
    Released: June 02, 2006
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    The formation of donor-acceptor complexes between MeSnCl3 and 4-substituted pyridines has been investigated by analyzing the concentration dependence of NMR parameters. The formation of 1(MeSnCl3):2(pyridine) and 1:1 complexes has been proved, and the equilibrium constants(K1 and K2) and complex formation shifts (ΔAB and ΔAB2) are determined for the successive formation of these complexes, logK1 and logK2 are in a good linear correlation with each other, and they have a tendency parallel with that of pKa of the pyridine derivative, suggesting a predominant contribution of σ-bonding in the donor-acceptor bond. Both ΔAB and ΔAB2 indicate a high-field shift on the formation of the complex, which is consistent with the expected electron transfer in the donor-acceptor bond. However, ΔAB varies inversely to the basicity of the pyridines; the anisotropy effect of the pyridine ring is suggested as the reason for this. The results are also discussed in relation to Hammett’s substituent constant.
  • Yoshio Hoshino, Taizo Utsunomiya, Osami Abe
    1981 Volume 54 Issue 5 Pages 1385-1391
    Published: 1981
    Released: June 02, 2006
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    The thermal decomposition of sodium nitrate and the effects of several oxides, such as silica, titania, zirconia, alumina, and magnesia, on the decomposition were studied up to 900 °C by means of the thermal analysis, gas analysis, and chemical analysis of the reaction products. The reaction of sodium nitrate and silica was especially investigated in some detail over a wide composition range. The thermal decomposition of sodium nitrate started at about 450 °C. The gases formed were O2, NO, and N2, the formation of N2 being detected above 680 °C The thermal decomposition of sodium nitrate was supposed to consist of the following three successive or concurrent reaction processes, according to the degree of the reaction: (I) the decomposition of sodium nitrate to nitrite and oxygen, (II) the first-order liquid-phase reaction, with some kind of quantitative relationship between nitrate and nitrite, and (III) the formation reaction of sodium oxide, expressed by the Avrami-Erofe’ef equation. The (II) and (III) reaction processes can be reasonably interpreted if the existence of the peroxide ion is assumed. Acidic oxides, such as silica and titania, were supposed to lower the activation energy of the (III) reaction process by forming stable salts with sodium nitrate and/or its intermediate reaction products. The effects of these oxides on the thermal decomposition of sodium nitrate could be interpreted by the relative scale of the acidity of oxides.
  • Keiichiro Hozumi, Keisuke Kitamura, Tatsuya Kitade
    1981 Volume 54 Issue 5 Pages 1392-1395
    Published: 1981
    Released: June 02, 2006
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    Structural interpretation of plasma-polymerized tetrafluoroethylene produced in a glow discharge chamber is given by referring to 19F-NMR and IR spectroscopy, elemental analysis, and number-average molecular weight determination. The polymer is hardly soluble in the usual organic solvents because of its highly branched structure, making NMR spectroscopy and molecular weight determination impossible. However, the polymer is soluble in 1,2-dibromo-1,1,2,2-tetrafluoroethane and the following structural interpretation could be obtained. The number-average molecular weight is 3600 for the majority of the polymer, consisting of 96 carbon and 129 fluorine atoms within a unit molecule. The IR spectrum shows evidence of some C=C groups and the 19F-NMR spectrum a highly branched and cross-linked structure in which a large number of quaternary carbons are involved in the polymer matrix as compared with CF2 and CF carbons. The plasma-polymerized tetrafluoroethylene has been characterized in a somewhat different way from the plasma-polymerized ethylene, involving a small number of quaternary carbons.
  • Tadashi Hara, Masakatsu Imaki, Motohiro Toriyama
    1981 Volume 54 Issue 5 Pages 1396-1399
    Published: 1981
    Released: June 02, 2006
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    In order to determine continuously the alkaline phosphatase activity in a serum sample, a potentiometric method using a newly prepared phosphate ion-selective electrode has been established by the authors for the first time. The alkaline phosphatase activity was determined by measuring the concentration of the phosphate ion which was liberated by the enzymatic hydrolysis of disodium phenyl phosphate in the presence of alkaline phosphatase. The measurement of the phosphate ion with an ion-selective electrode was seriously interfered with by protein and the halide ion, but the interference could be removed by covering the electrode surface with a cellulose acetate membrane and by separating the chloride ion from a serum sample by gel chromatography. The present method was applied to the determination of alkaline phosphatase activity in serum; the results obtained showed a satisfactory correlation with those obtained by the conventional method. The method was found to be useful for practical diagnosis based on the activity of alkaline phosphatase.
  • Katsumi Kitamura, Koichi Hasegawa, Katsura Mochizuki, Taira Imamura, M ...
    1981 Volume 54 Issue 5 Pages 1400-1402
    Published: 1981
    Released: June 02, 2006
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    The concentration of hyperoxide, O2, in dimethyl sulfoxide (DMSO) was determined by photometric titration with iodine. The validity of the method was confirmed on the basis of stoichiometry by use of the standardized hyperoxide solution in the reaction of the complex, MoO(tpp)NCS, with methanol, where TPP denotes α,β,γ,δ-tetraphenylporphyrin.
  • Yoshihiro Shigemasa, Tsuyoshi Taji, Eiichi Waki, Ruka Nakashima
    1981 Volume 54 Issue 5 Pages 1403-1409
    Published: 1981
    Released: June 02, 2006
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    It was found that a formose reaction in the presence of small amounts of calcium and D-fructose gave rise to three products, 2-(hydroxymethyl)glycerol, 3-(hydroxymethyl)pentitol, and 2,4-bis(hydroxymethyl)pentitol, with a high selectivity. Various factors affecting the selectivity were also discussed: [Ca], pH, [D-fructose], the reaction temperature, co-catalysts, and metal hydroxides. The amount of formaldehyde relative to [Ca] is the most important factor in obtaining the selective formation of the three-branched sugar alcohols. Under these reaction conditions, the α,β-enediol structure is required in an effective co-catalyst for the formose reaction. 2-(Hydroxymethyl)glycerol, 3-(hydroxymethyl)pentitol, and 2,4-bis(hydroxymethyl)pentitol were formed with a high selectivity in the formose reactions catalyzed by KOH, Mg(OH)2, Fe(OH)3, and LiOH.
  • Tomihiro Nishiyama, Yasushi Nakai, Hideaki Shishibori, Fukiko Yamada
    1981 Volume 54 Issue 5 Pages 1410-1414
    Published: 1981
    Released: June 02, 2006
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    The title compounds were prepared, and their 1H- and 13C-NMR spectra were examined. On the basis of the data for the benzene–solute collision complexes and the magnitudes of the γ shifts, five isomeric conformations of the compounds were discussed.
  • Toshizumi Tanabe, Kiyoshi Yamauchi, Masayoshi Kinoshita
    1981 Volume 54 Issue 5 Pages 1415-1419
    Published: 1981
    Released: June 02, 2006
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    The quantitative determination of adenosine, guanosine, inosine, cytidine, uridine, and their methylated derivatives was studied by means of a high-performance liquid chromatographic method using ODS–silica gel cation-exchange, and anion-exchange resins as column packings. The method was apphed to the analysis of yeast-RNA, which was methylated by trimethyl phosphate at pH 7 and 9.
  • Seizi Kozuka, Tetsuji Higashino, Takuro Kitamura
    1981 Volume 54 Issue 5 Pages 1420-1423
    Published: 1981
    Released: June 02, 2006
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    A kinetic study has been conducted on the reactions of (arylthio)trimethylsilanes with phenacyl bromide giving aryl phenacyl sulfides and bromotrimethylsilane. Remarkably large positive substituent effect (ρ=+2.2) and large negative entropy of activation were observed for the reaction. A mechanism involving 5-coordinated silicon intermediate prior to the rate-determining heterolysis of the Si–S bond has been suggested for the reaction based on the kinetic results.
  • Akira Hirao, Masaki Ohwa, Shinichi Itsuno, Hidenori Mochizuki, Seiichi ...
    1981 Volume 54 Issue 5 Pages 1424-1428
    Published: 1981
    Released: June 02, 2006
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    Asymmetric reduction of prochiral aromatic ketones using a freshly prepared complex derived from NaBH4, 1/3 equiv of ZnCl2, and 1,2 : 5,6-di-O-isopropylidene-α-D-glucofuranose (1) gives an excess of the corresponding (S)-alcohols in substantial optical yields (28–68%). The effects of the NaBH4/ZnCl2/1 ratio, temperature, solvent, structure of various monosaccharide derivatives, and the metal cation of the reagent on the optical yields were examined.
  • Tatsuo Oida, Tomio Shimizu, Yoshiyuki Hayashi, Kazuhiro Teramura
    1981 Volume 54 Issue 5 Pages 1429-1433
    Published: 1981
    Released: June 02, 2006
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    The cycloaddition of nitrilimines with 1,2-dibenzoylethylenes gave an unexpected 1,3-diaryl-4-benzoylpyrazole and benzoic acid, along with an expected cycloadduct, 1,3-diaryl-4,5-dibenzoyl-2-pyrazoline, and its dehydrogenated product, 1,3-diaryl-4,5-dibenzoylpyrazole. The elimination of the benzoyl group from the pyrazoline followed by dehydrogenation was shown to be the course of the unusual reaction.
  • Shigeo Jo, Shigeo Tanimoto, Tatsuo Oida, Masaya Okano
    1981 Volume 54 Issue 5 Pages 1434-1436
    Published: 1981
    Released: June 02, 2006
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    The reaction of 2-ethoxy-1,3-dithiolane with carbonyl compounds such as aldehydes and ketones was investigated. The reaction proceeded smoothly in the presence of the HgCl2-catalyst to afford 2-substituted and 2,2-disubstituted 1,3-dithiolanes. The reaction also offers an interesting alternative to the previously reported methods of synthesizing 1,3-dithiolanes which involve the acid-catalyzed reaction of carbonyl compounds with 1,2-ethanedithiol.
  • Katsumi Hayashi, Masanosuke Takagi
    1981 Volume 54 Issue 5 Pages 1437-1442
    Published: 1981
    Released: June 02, 2006
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    Oxygen transport by human hemoglobin (Hb) to an electrode surface with hypo-oxygen partial pressure has been studied by the polarographic technique. The oxygen reduction current in Hb solution open to the atmosphere increased linearly with Hb concentration up to ca. 2 mM (1 M=1 mol dm−3) heme. The current was ascribed to free and Hb bound oxygen. The increase in current with Hb concentration was attributed to the increasing oxygen supply to the electrode from oxygen bound Hb (oxyhemoglobin;oxyHb). Changes in temperature and pH largely affected the current, corresponding to the change in dissociation rate of oxygen from oxyHb. The relation between the current due to oxyHb and the apparent first order rate constant of the dissociation (k) measured by the stopped-flow method implies two different rate-determining steps of oxygen transport by Hb. When k exceeded ca. 60 s−1, the limiting step altered from the dissociation of oxygen to the diffusion of Hb molecules. It is concluded that the oxygen transport by Hb on physiological conditions is controlled by the diffusion of Hb. The diffusion coefficient of Hb in 20 mM heme as found in erythrocytes was estimated to be 5.8×10−8cm2 s−1 at 25 °C and pH 7.4.
  • Toshikazu Takata, Yong Hae Kim, Shigeru Oae
    1981 Volume 54 Issue 5 Pages 1443-1447
    Published: 1981
    Released: June 02, 2006
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    Unsymmetrical thiosulfinic S-esters were oxidized with sodium metaperiodate in aqueous media to the corresponding unsymmetrical thiosulfonic S-esters nearly quantitatively. The oxidation was accelerated by addition of a catalytic amount of inorganic and organic acids or halogen. Sulfinic esters were produced competitively along with the thiosulfonic S-esters in the oxidation of thiosulfinic S-esters in aqueous alcohol. However, unsymmetrical disulfides were not oxidized selectively to the corresponding unsymmetrical thiosulfonic S-esters but a mixture of both symmetrical and unsymmetrical thiosulfonic testers was obtained.
  • Takashi Matsumoto, Sachihiko Imai, Shuhei Yuki
    1981 Volume 54 Issue 5 Pages 1448-1455
    Published: 1981
    Released: June 02, 2006
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    Treatment of methyl (+)-11-oxo-13β-abieta-8-en-18-oate with copper(II) bromide and lithium bromide afforded the corresponding phenol derivative, which was methylated to methyl 11-methoxyabieta-8,11,13-trien-18-oate (7). The same compound was also prepared from methyl (+)-7,11-dioxo-13β-abieta-8-en-18-oate via methyl 11-hydroxy-7-oxoabieta-8,11,13-trien-18-oate, its methyl ether, and methyl 11-methoxyabieta-6,8,11,13-tetraen-18-oate. The Grignard reaction of 7 with phenylmagnesium bromide followed by treatment with lead tetraacetate and subsequent oxidation with selenium dioxide afforded 11-methoxy-19-norabieta-4(18),8,11,13-tetraen-3α-ol (12), which was converted to 11-methoxy-19-norabieta-8,11,13-trien-3-one (20) by catalytic hydrogenation, Jones oxidation, and isomerization. The compound 20 was also obtained by Birch reduction of 11-methoxy-19-norabieta-4,8,11,13-tetraen-3-one prepared from 12 via 11-methoxy-19-norabieta-4,8,11,13-tetraen-3α-ol. Subsequently, the compound 20 was transformed to 11-methoxyabieta-1,8,11,13-tetraen-3-one (27) by a series of reactions: acetalization, demethylation, hydrolysis, acetylation, bromination, dehydrobromination, and methylation. Finally, the compound 27 was converted to the title compound, (+)-11-hydroxyabieta-2,8,11,13-tetraen-1-one (1), by oxidation with alkaline hydrogen peroxide, heating with hydrazine hydrate, Jones oxidation, and demethylation. Although the synthetic (+)-1 was shown to be different from natural shonanol, the spectral analyses of the synthetic structural isomers showed the structure of shonanol to be 12-hydroxyabieta-2,8,11,13-tetraen-1-one.
  • Akira Itoh, Tadashi Saito, Koichiro Oshima, Hitosi Nozaki
    1981 Volume 54 Issue 5 Pages 1456-1459
    Published: 1981
    Released: June 02, 2006
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    Nerol was cyclized to terpinyl chloride or bromide in the presence of TiX4–PhNHMe (1 : 1) complex (I, X= Cl, Br) in dichloromethane at −23 °C, geraniol being converted into geranyl halide by simple halogenation. Terminally modified derivatives YCH2C(Me)=CHCH2CH2CMe=CHCH2OH (Y=SiMe3, SnBu3) of (2Z,6E) configuration were cyclized by treatment with I to afford limonene in high yields and 100% selectivity. Cyclization of (2Z) isomers of CH2=CR–CH2CH2CMe=CHCH2OH (R=H, Me, Cl) produced seven-membered carbocyclic products in fair yields. The novel procedure has been utilized in the synthesis of nezukone from (2E)-3-isopropyl-2,6-heptadien-1-ol involving five steps.
  • Nobuaki Kambe, Kiyoshi Kondo, Hideo Ishii, Noboru Sonoda
    1981 Volume 54 Issue 5 Pages 1460-1464
    Published: 1981
    Released: June 02, 2006
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    Carbonylation of amines with carbon monoxide was catalyzed by tellurium to produce corresponding urea derivatives, formamides, and molecular hydrogen. The urea formation proceeds according to the equation; 2RNH2+CO→(RNH)2CO+H2. The successful achievement of the catalytic formation of urea derivatives would be due to the thermal instability of hydrogen telluride which decomposes to generate elemental tellurium and hydrogen. The formation of formamides and hydrogen was found to be suppressed by the addition of nitrobenzene which did not affect the urea formation. Effects of the reaction time, temperature, pressure of carbon monoxide, and additives on this carbonylation reaction are discussed.
  • Shigetaka Seki, Tsutou Morinaga, Hiromi Kikuchi, Tsutomu Mitsuhashi, G ...
    1981 Volume 54 Issue 5 Pages 1465-1469
    Published: 1981
    Released: June 02, 2006
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    The methyls in a t-butyl group are shown to exhibit different reactivities in radical halogenations, if rotation about a (CH3)3C–CXY2 bond is frozen. Barriers to rotation of halogenated 9-t-butyl-1,2,3,4-tetrachlorotriptycenes are obtained as ΔH\ eweq ca. 32 kcal/mol. The cause of the selectivity in chlorination with sulfuryl chloride was discussed by obtaining reactivity data with a variety of compounds and halogenating reagents. It is concluded that the neighboring group participation of the peri-halo substituent is responsible for the observed selectivity.
  • Seiji Takimoto, Junji Inanaga, Tsutomu Katsuki, Masaru Yamaguchi
    1981 Volume 54 Issue 5 Pages 1470-1473
    Published: 1981
    Released: June 02, 2006
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    When mixtures of carboxylic acids or their sodium salts and alcohols were treated with 2-chloro-1,3,5-trinitrobenzene in the presence of pyridine under mild conditions, the corresponding carboxylic esters were formed. The yields and the rates of the ester formation depended on the types of the acids and the alcohols used.
  • Yasuo Sakai, Shingo Toyotani, Masaru Ohtani, Masaharu Matsumoto, Yoshi ...
    1981 Volume 54 Issue 5 Pages 1474-1480
    Published: 1981
    Released: June 02, 2006
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    The bridgehead-substituted bicyclo[n.2.2] bridgehead alkenes (1b3b) (1, n=4; 2, n=5; 3, n=6; b, R=OAc) were synthesized based on the oxidative decarboxylation of [n.2.2]propellanecarboxylic acids with lead tetraacetate. The parent alkene (1a3a) (a, R=H) and other bridgehead-substituted derivatives (1c3c and 1d3d) (c, R=OH; d, R=Cl) were prepared from 1b3b. The examination of the 13C NMR chemical shifts of 1ac, 2ac, and 3ac indicates the presence of electronic interaction between the bridgehead double bond (Cγ) and the opposite bridgehead carbon (Cα), being the homoallylic position of the double bond. From the product study and the kinetic results of the solvolysis of the bridgehead chlorides 1d3d, it is indicated that the homoallylic participation of the strained bridgehead double bond to the carbonium ion center located at the opposite bridgehead position operates in the solvolysis of 1d and 2d. It may be, therefore, concluded that highly strained bridgehead alkenes, especially, bicyclo[4.2.2]decene system, show remarkable homoallylic type α, γ-interaction both in the ground state and in the transition state (carbonium ion).
  • Hajime Yasuda, Michihide Yamauchi, Yasuo Ohnuma, Akira Nakamura
    1981 Volume 54 Issue 5 Pages 1481-1491
    Published: 1981
    Released: June 02, 2006
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    The configurational analysis of a series of alkyl substituted pentadienyl anions in THF was examined by trimethylsilylation and from the variable temperature 1H- and 13C-NMR spectra. Potassium pentadienide, -2-methylpentadienide or -2,4-dimethylpentadienide produced preferentially (Z)-2,4-pentadienyltrimethylsilane or its methyl substituted analogues to indicate that these compounds have the “U”-shaped structure in solution. By contrast, trimethylsilylation of potassium pentadienide and -2-methylpentadienide in the crystalline state produced the (E)- and the (E),(Z)-isomers, respectively, suggesting that the geometry is drastically changed to the “W”- or “S”-shaped by the medium effect. The W-shaped structure of potassium 3-methylpentadienide in THF and in the solid state is exceptional. Geometry of trapped products of potassium cycloheptadienide and -cyclooctadienide is also (Z) but the silylation occurred on the central carbon in contrast to the terminal silylation seen for the open-chain pentadienides. Geometry of these dienyl anions determined by NMR below −30 °C was consistent with the result obtained from trimethylsilylation. Superficial conflict between MINDO/3 prediction and the experimental evidence was reasonably reconciled by considering contact ion pairs for potassium pentadienide in THF and more strongly-solvated ion pairs for the lithium analogues.
  • Masajiro Kawana, Hiroyoshi Kuzuhara, Sakae Emoto
    1981 Volume 54 Issue 5 Pages 1492-1504
    Published: 1981
    Released: June 02, 2006
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    The anomerization of methyl glycofuranoside derivatives with methylmagnesium iodide or t-butylmagnesium bromide occurred in a one-way manner. For example, methyl 5-O-benzyl-β-D-ribofuranoside () was converted into the corresponding α-anomer () in a 95% yield when a mixture of and t-butylmagnesium bromide in benzene–ether was heated at about 75 °C to remove the ether; the reverse reaction (from to () did not proceed. The reaction of with methylmagnesium iodide gave open-chain products (33%), besides (30%). Twenty kinds of anomers were tested, and the mechanisms of the reactions were discussed. The cleavage of a benzyl- or trityl-protecting group with the Grignard reagent was also observed during the reaction.
  • Yasunobu Inoue, Iwao Yasumori
    1981 Volume 54 Issue 5 Pages 1505-1510
    Published: 1981
    Released: June 02, 2006
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    X-Ray photoelectron spectroscopy was used to reveal the surface states of MgO, CaO, and BaO oxides, which are catalytically active for ethylene hydrogenation. The catalytic activity of CaO exposed to H2O changed with an increase in the temperature of evacuation in a way similar to that of Ca(OH)2 decomposed by heat treatment. The photoelectron spectrum of CaO evacuated at 1223 K showed a peak of O Is at 529.6 eV, while those of Ca 2p3⁄2 were at 346.3 eV and Ca 2p1⁄2 at 349.8 eV. The adsorption of H2O at room temperature gave rise to an additional peak of O Is at 532.4 eV and one of Ca 2p3⁄2 at 348.6 eV, which were attributed to a Ca–O–H structure. With an increase in the temperature of evacuation from 553 to 1053 K, at which the catalytic activity attained a maximum, the latter O Is peak shifted to the lower binding-energy side by 0.4 eV, and the corresponding Ca 2p peak became broader. These spectral variations were ascribable to the formation of O species. Evacuation above 1273 K destroyed both the catalytic activity and characteristic peaks. BaO provided three O Is peaks, at 528.5, 530.6, and 532.1 eV, after evacuation at 1373 K; these peaks were assigned to lattice oxygen of the oxide, O, and OH species respectively. The Ba 4d spectra showed correspondingly superposed peaks. The XPS peak due to O was observed only when BaO was evacuated at temperatures high enough to generate the catalytic activity. Such spectral features were less pronounced in the case of MgO. The structural analysis of CaO showed that the coordinatively unsaturated cations also play a role in the catalytic hydrogenation. On the basis of these findings, it was concluded that a combined structure of O and the cations is responsible for the hydrogenation activity.
  • Nobuko Igarashi, Akio Tajiri, Masahiro Hatano
    1981 Volume 54 Issue 5 Pages 1511-1516
    Published: 1981
    Released: June 02, 2006
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    The MCD spectra of the monobenzo and dibenzo derivatives of thiophene and furan are reported; especially in dibenzofuran, two electronic origins are revealed in its lowest energy absorption band. The quantum-mechanical calculations of the transition energies and the Faraday parameters elucidate the experimental data to a fair extent, suggesting similarities in the electronic structures of the lower-lying excited states of furan and thiophen derivatives.
  • Takeshi Ohno, Shunji Kato
    1981 Volume 54 Issue 5 Pages 1517-1522
    Published: 1981
    Released: June 02, 2006
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    The fluorescence quenching of solvent molecules and solute molecules was studied in the alkylnaphthalene solvents. The singlet-excited states of the solvent molecules were quenched by 1,4-bis(trichloromethyl)benzene with the rate parameter of 2.8×1010 mol−1 dm3 s−1 at 45 °C. This rate parameter is twelve times as great as that of the solute, dibenz[a,c]anthracene, in the solvent, 1-methylnaphthalene. The diffusion constant of the excitation migration of the solvent molecule is calculated to be larger (0.35×10−4 cm2 s−1 at 45 °C) than that (0.03×10−4 cm2 s−1) of the solute. The temperature coefficient (22 kJ/mol) of the excitation migration is too small to explain the migration mechanism on the hypothesis of the “successive association-dissociation reaction of excimer” proposed by Birks. The presence of a short-range exciton in the liquid is likely.
  • Mitsuru Sano, Yasuyo Hatano, Hiroshi Kashiwagi, Hideo Yamatera
    1981 Volume 54 Issue 5 Pages 1523-1530
    Published: 1981
    Released: June 02, 2006
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    Ab initio LCAO MO SCF calculations were carried out on [Co(CN)6]3−. The character of the wave-functions was discussed in terms of the orbital-mixing rule. The radial distribution of electron density obtained from molecular orbital (MO) calculation was compared with that obtained from X-ray experiments. On the ionization from a metal d-orbital, a significant electronic relaxation was shown to occur, which makes Koopmans’ theorem invalid. The calculated excitation energies without a configuration interaction showed a qualitative correspondence with the absorption spectrum.
  • Kenshi Tsuji, Shuhei Fujinami, Muraji Shibata
    1981 Volume 54 Issue 5 Pages 1531-1537
    Published: 1981
    Released: June 02, 2006
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    Five carbonato complexes, [Co(CO3)(ox)(tn)], cis-[Co(CO3)(ox)(py)2], cis·cis-[Co(CO3)(NH3)2(py)2]+, cis-[Co(CO3)(en)(py)2]+, cis-[Co(CO3)(NH3)2(bpy)]+, and two related complexes, cis-[Co(ox)(NH3)2(en)]+ and cis-[Co(mal)(NH3)2(en)]+, have been prepared and resolved. The solution CD spectra of these resolved complexes and those of diaqua complexes derived from the carbonato complexes have been measured. The CD spectral comparison in the first absorption band (T1g-band) region has suggested a relation in the sign of the Cotton peak between each of the carbonato complexes and the corresponding diaqua complex. Based on this relation, the assignments of the absolute configurations for the present complexes have been established.
  • Toshiji Tada, Yoshihiko Kushi, Hayami Yoneda
    1981 Volume 54 Issue 5 Pages 1538-1543
    Published: 1981
    Released: June 02, 2006
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    The crystal structure of the less-soluble diastereomeric salt, (−)589-[Co(Hbg)3]Cl(d-tart)·5H2O, has been determined by X-ray analysis (R=0.056, 1277 reflections). The crystals are orthorhombic, with the space group of C222, Z=4, a=24.846(5), b=12.970(2), and c=8.645(2) Å. The main features of the crystal structure are as follows: (1) The complex cation and Cl anion are arranged alternately along the b-axis to form an infinite spiral chain. The distances between N(Hbg) and Cl are 3.452 and 3.376 Å. (2) The tartrate ions exist as a dimeric unit whose structure closely resembles that of [Sb2(d-tart)2]2−. Through the center of this dimeric unit pass three mutually orthogonal twofold axes. (3) There are short contacts between the Hbg ligands and the tartrate ions along the twofold axis of the complex; N(A2)···OT3 2.862, N(B2)···OT2 3.116, N(B3)···OT2 2.754, and N(B4)···OT1 2.963 Å. On the basis of these features, the chiral discrimination mechanism is discussed.
  • Tetsuo Katsuyama, Toshihiko Kumai
    1981 Volume 54 Issue 5 Pages 1544-1547
    Published: 1981
    Released: June 02, 2006
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    N,N′-Bis(2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (hbed) reacts with iron(III) to form a red complex having an absorption maximum at 485 nm. The iron(III) complex is so stable that the maximum absorbance of the solution is constant over the pH range from 2.5 to 13.2 and a large excess of reagent is not necessary. Beer’s law is obeyed up to 1.6×10−4 mol dm−3 (9 μg cm−3) of iron(III). The molar absorption coefficient is 3.95×103 1 cm−1 mol−1, and the relative standard deviation for determination of 3.5 μg cm−3 of iron was 0.29%. The molar ratio of iron(III) to hbed was found to be 1 : 1. The effect of 32 diverse ions was examined; only colored aqua metal ions interfere. The present method was applied to the determination of iron in aluminium alloys.
  • Sei-ichiro Imamura, Yoshiaki Tonomura, Nariyoshi Kawabata, Takane Kita ...
    1981 Volume 54 Issue 5 Pages 1548-1553
    Published: 1981
    Released: June 02, 2006
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    Wet oxidation of various water-soluble polymers was carried out with particular attention given to the reactivity of polyethylene glycol. Polymers with high molecular weight were more reactive than their low molecular weight analogues or monomer models. It is suggested that the high reactivity of the polymers can be attributed to the ease of an intramolecular hydrogen abstraction in the propagation step of oxidation. Bio-degradability of the polymers was highly improved by wet oxidation. Wet oxidation is especially effective for the treatment of waste water containing water-soluble polymers.
  • Ganesh Prasad Panigrahi, Abhina Kumar Panda
    1981 Volume 54 Issue 5 Pages 1554-1558
    Published: 1981
    Released: June 02, 2006
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    Anthranilic acid and p-aminobenzoic acid were oxidized with peroxomonophosphoric acid in aqueous acid medium to the corresponding azoxy derivatives. Suitable rate laws for the double bell shaped pH rate profile were derived and rationalized on the basis of protonation of the amino group and ionization of the carboxyl group. The mechanism of oxidation involves the nucleophilic attack of nitrogen on the electrophilic peroxo oxygen. The reactivity of different peroxomonophosphoric acid species has been estimated.
  • Takashi Nogami, Toshio Mizuhara, Naoki Kobayashi, Masaaki Aoki, Takao ...
    1981 Volume 54 Issue 5 Pages 1559-1560
    Published: 1981
    Released: June 02, 2006
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    Monophotonic ionization of N,N,N′,N′-tetramethyl-1,6-pyrenediamine (TMPDA) in acetonitrile was studied by means of ns laser photolysis and transient photocurrent measurement. The time dependences of the absorption of TMPDA cation radical and of the photocurrent were different. Photoionization thus occurs through an ionpair state.
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