Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 52 , Issue 1
Showing 1-50 articles out of 73 articles from the selected issue
  • Hiroyuki Shinohara, Akira Imamura, Takahiro Masuda, Masaharu Kondo
    1979 Volume 52 Issue 1 Pages 1-7
    Published: 1979
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    The reactivities of hydrogen atoms of aliphatic amino acids toward hydroxyl radicals in the hydrogen atom abstraction reaction have been studied in terms of the energy required for stretching the C–H bond which is attacked. The energy required for stretching the C–H bond by 0.5 Å from the equilibrium bond length has been calculated by the INDO method and compared with the partial rate constants experimentally assigned to the hydrogen atoms of aliphatic amino acids. The energy required has been correlated only with the partial rate constants of the hydrogen atoms on the β-carbon atom. For the hydrogen atoms on the α-carbon atom, although data was insufficient a similar situation has been observed. The reactivities of the hydrogen atoms on the γ and δ-carbon atom failed to correlate with the stretching energy. The reasons are discussed in terms of the effect raised by the configuration of amino acid molecules in solution. The stretching energy has also been found to be consistent with the electrophilicity observed in the hydrogen abstraction reaction by hydroxyl radical.
  • Yukio Yoneda
    1979 Volume 52 Issue 1 Pages 8-14
    Published: 1979
    Released: April 19, 2006
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    The system GRACE generates elementary reaction networks for simple reactions including free radicals, ions and even active sites in heterogeneous catalysis, and also predicts the overall reaction rates and the product distributions in radical reactions in the gas phase where the Arrhenius parameters of elementary reactions are available. In this paper, A/GRACE (part A of GRACE) is explained, which prepares elementary reaction networks for radical reactions. The reactant and the product are represented by square symmetric matrices. The off-diagonal elements represent bond multiplicity, or the number of localized electrons, between corresponding atoms, whereas the diagonal elements imply the number of unshared electrons on radical atoms. A reacting system, an ensemble of the participating molecules, is composed of atom groups, each of which consists of a center atom (usually non-hydrogen) and attached hydrogen atom(s), if any. Firstly, all the possible changes in the atom groups are selected, and the permitted combinations are preapred bearing in mind the equivalent groups in the system and the restrictions optioned. The major restriction is the complexity, i.e., the number of ruptured or formed bonds. A direct sum of matrices are prepared from one of the combinations, and the elementary reaction is completed by setting the appropriate numerals, 1 or −1, to the outside elements. Secondly, the procedures are repeated until all the feasible networks are prepared. As an illustration the hydrogenation of ethylene over a heterogeneous catalyst has been cited.
  • Akiko Sibata, Makoto Takahasi, Hitoshi Mikuni, Hiroyuki Horiguchi, Soj ...
    1979 Volume 52 Issue 1 Pages 15-20
    Published: 1979
    Released: April 19, 2006
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    Chemiionization of excited mercury atom with 253.7 nm irradiation was studied. Results on the system Hg–N2 previously reported were further confirmed. It was found that CH4 can also induce chemiionization of Hg atoms with 253.7 nm irradiation. The dependence of ionization current on CH4 pressure and light intensity was investigated, the ionization current being found to be proportional to the square of light intensity and to increase with increase in CH4 pressure up to 30 Torr, reaching a constant value. N2 and CH4 are considered to show a similar behavior in ionization current against pressure and light intensity, and other substances such as H2, He, CO, NO, Ar, C2H4, and 1-butene to give no appreciable ionization current. Thus the mechanism in which chemiionization proceeds through the collision of Hg(3P1) with Hg(3P0) is further confirmed.
  • Takahisa Doba, Shoji Noda, Hiroshi Yoshida
    1979 Volume 52 Issue 1 Pages 21-24
    Published: 1979
    Released: April 19, 2006
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    In order to extend kinetic utilization of the spin-trapping techniques in radiation chemistry, γ-radiolysis of cyclohexane has been studied at room temperature using pentamethylnitrosobenzene as a spin trap. With increasing radiation dose, the cyclohexyl radical spin adduct has been found by ESR to form and then decay. Consumption of the spin trap has also been monitored by observing the optical absorption. The observed kinetic aspects indicate that the radiation-generated cyclohexyl radicals are completely trapped by 1.3×10−4–6.6×10−4 mol dm−3 of the spin trap, and their G-value is 3.0. The spin-trapping rate constant has been determined to be 1.6×107 mol−1 dm3 s−1 at 299 K based on the reported rate constant for the reaction between the cyclohexyl radical and tributylstannane. From the optical absorption study, dimeric pentamethylnitrosobenzene has been found to dissociate into the monomer, effective in the spin-trapping, with an equilibrium constant of 8×10−4 mol dm−3 in cyclohexane at 299 K. The monomer has an absorption coefficient of 48 mol−1 dm3 cm−1 at its absorption peak of 790 nm.
  • Kikuko Hayamizu, Osamu Yamamoto
    1979 Volume 52 Issue 1 Pages 25-29
    Published: 1979
    Released: April 19, 2006
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    Selectively deuterated PAA’s, PAA-d8, and PAA-d6 have been studied by proton NMR from 77 K to the melting point (390 K). The temperature dependences of T1 the line width, and the second moment for these compounds are presented. It has been demonstrated that PAA is in the rigid state at 77 K on an NMR time scale, and as the temperature increases the two methyl groups begin to rotate about the C3 axis, followed by libration about the C–O axis. There is no evidence for motions of the ring protons except self-diffusion and/or slow reorientation of the molecular axis in the higher temperature range from 286 K to the melting point.
  • Fumitaka Yamashita, Tsuyoshi Komatsu, Tsurutaro Nakagawa
    1979 Volume 52 Issue 1 Pages 30-33
    Published: 1979
    Released: April 19, 2006
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    The copper(II) complex formation with poly(acrylic acid) and poly(methacrylic acid) in aqueous solution was studied by potentiometric titration employing glass and copper(II) ion-selective electrodes. The values of the equilibrium constants of the complex formation and the stability constants were estimated in various degree of neutralization. Since the concentration of free copper(II) ions could be determined by employing the copper(II) ion-selective electrode, the concentrations of two complex species, involving one and two carboxylato groups, were determined from stoichiometric equations. The equilibrium and stability constants of the complexes obtained were observed to pass through peaks with increase in the degree of neutralization. The order of magnitude of the equilibrium constant of the polyacrylate complex was larger than that of the polymethacrylate complex.
  • Taro Tachibana, Tokiko Yoshizumi, Kayako Hori
    1979 Volume 52 Issue 1 Pages 34-41
    Published: 1979
    Released: April 19, 2006
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    The monolayer properties of chiral and racemic 12-hydroxyoctadecanoic acids (12HOA) have been studied. Both acids showed, in each pressure-area isotherm, a pressure plateau. This was interpreted as a two-dimensional phase transition region: from the expanded monolayer composed of bent chain molecules with both the hydroxyl and carboxyl groups attached to the water surface, to the condensed monolayer composed of straight chain molecules oriented steeply to the water surface. It was suggested by measuring infrared spectra of the collapsed films and the built-up films that the condensed monolayer involves intermolecular hydrogen bonds. Differences between (R)- and dl-12HOA were found in the plateau pressure and its temperature dependence leading to the transition energy. These results were attributed to the formation of a recemic molecular compound during condensation of monolayers of dl-12HOA, prior to collapse, followed by a different manner of hydrogen bonding. Electron microscope observation gave strong evidence for the two-dimensional racemic compound formation. On the basis of these results and the X-ray diffraction data, molecular packing models in the condensed monolayers were proposed.
  • Shoji Kaneshina, Osamu Shibata, Makoto Nakamura
    1979 Volume 52 Issue 1 Pages 42-44
    Published: 1979
    Released: April 19, 2006
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    Cloud points in 1.0 wt% aqueous solutions of penta- and hexa(oxyethylene) dodecyl ether increase monotonously with an increase of pressure up to 150 MPa. The elevation of the cloud-point temperature with pressure was 1.05×10−7 and 1.09×10−7 K Pa−1 for respective surfactant. Both volume and enthalpy changes on the separation of the surfactant-rich phase had the positive values. The rise of cloud points on compression is attributable to the enhancement of the hydrogen bonds formation between water and ether oxygens of the poly(oxyethylene) group and partly to the disruption of the “hydrophobic bonding.” The cloud-point temperature at conscant pressure and the cloud-point pressure at constant temperature were also examined as a function of the amount of solubilizate such as hexane and octane. There was an optimum pressure at a given temperature, as well as an optimum temperature at a given pressure, at which the solubilizing power of surfactant is maximum.
  • Kenji Inoue, Michiya Itoh
    1979 Volume 52 Issue 1 Pages 45-48
    Published: 1979
    Released: April 19, 2006
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    Dual fluorescence of the ground state dimer of highly polar molecules of 3,5-dialkyl-4-methoxybenzylidenemalononitrile in 3-methylpentane solution at low temperature was investigated by steady-state and nonsecond fluorescence spectroscopies. The dimerization of these compounds was confirmed by concentration dependence of absorption and fluorescence spectra at 77 K. The dimer exhibits dual fluorescence consisting of a short-lived dimer fluorescence and a long-lived excimer fluorescence, while the monomer is almost nonfluorescent at room temperature to 77 K. The excimer formation by an orientational relaxation from the excited state of the dimer was discussed in terms of determination of the activation barrier and the fluorescence polarization.
  • Masuhiro Kato, Akio Takenaka, Yoshio Sasada
    1979 Volume 52 Issue 1 Pages 49-51
    Published: 1979
    Released: April 19, 2006
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    The crystal structure of 5-bromocytosfne has been determined by X-ray analysis to investigate the bromination effect on the cytosine moiety. The space group is P21/a, with dimensions a=16.943(2), b=9.155(1), c=3.846(1) Å, β=99.89(1)°, and Z=4, The structure was solved by the heavy-atom method and refined by the full-matrix least-squares method. A comparison with the cytosine structure indicates some large deviations in bond lengths and angles, which are attributed to the steric and electronic effects caused by bromination. After the VSEPR theory, the slight increase of C(2)–N(3)–C(4) angle (0.8°) is interpreted as the decrease of the effective charge of the lone pair on N(3), and this is related to the difference of pKa values between 5-bromocytosine and cytosine.
  • Haruo Nakayama
    1979 Volume 52 Issue 1 Pages 52-56
    Published: 1979
    Released: April 19, 2006
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    The solid-liquid phase diagrams are presented for binary mixtures of water with various polymethylene-bis(tributylammonium) difluorides, [(n-C4H9)3N(CH2)nN(n-C4H9)3]F2 (n=4, 5, 6, 8, and 10); and with hexamethylenebis(tributylammonium) dihydroxide and its salts, [(n-C4H9)3N(CH2)6N(n-C4H9)3](X2 or Y) (X=OH, Cl, and Br; Y=OOC–COO and OOC–(CH2)3–COO). It has been found that all the compounds form congruently melting hydrates which have large hydration numbers. The hydrates appear to be clathrate-like hydrates essentially similar to those formed by many tetrabutyl(or isopentyl) ammonium salts. The most stable hydrate found in this study is [(n-C4H9)3N(CH2)6N(n-C4H9)3]F2 hydrate (mp 20.4 °C). The melting points of hexamethylenebis(tributylammonium) hydrates have been compared with those of the corresponding tetrabutylammonium hydrates.
  • Reiko Saito, Yoshinori Kidani
    1979 Volume 52 Issue 1 Pages 57-60
    Published: 1979
    Released: April 19, 2006
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    A series of 1,3-chxn(cis-1,3-cyclohexanediamine) copper(II) and nickel(II) complexes have been prepared and studied using spectroscopic and magnetic techniques. The violet and red copper(II) complexes of 1,3-chxn were found to consist of monomeric distorted octahedra and slightly distorted square planers, respectively. The nickel(II) complexes have a square planar structure. The conformational change of the ligand from diequatorial to diaxial on coordination has been confirmed by infrared analysis.
  • Masatoshi Watabe, Hisao Yano, Sadao Yoshikawa
    1979 Volume 52 Issue 1 Pages 61-64
    Published: 1979
    Released: April 19, 2006
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    The six isomers of the [Co(L- or D-asp)(L-his)] complex (asp=aspartate ion and his=histidinate ion) have been prepared and the isomerization studied in the absence of any catalyst. The equilibrium mole fractions of these isomers in water has been found for L-transO5cisN5, L-cisO5transN5, L-fac, to be 0.53, 0.06, and 0.41, respectively, those for D-cisObcisN5, D-transO5transN5, and D-fac to be 0.48, 0.01, and 0.51 respectively. The indication is that the relative positions of the six coordinated atoms around a cobalt atom cause these unequal isomer concentration ratios. The isomerisms are dealt with by means of a network of first order reversible reactions and the absolute values of the rate constants at 80 °C have been determined.
  • Rebati C. Das, Osamu Koga, Shin Suzuki
    1979 Volume 52 Issue 1 Pages 65-68
    Published: 1979
    Released: April 19, 2006
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    The mass spectrometry of alkyl nitrites and alkyl nitrates with chemical ionization using methane and isobutane as reagent gases produces quasi-molecular ions, (M+1)+ and/or (M−1)+. These ions have maximum abundance for lower nitrates and nitrites. The chemical ionization mass spectrometry, in conjunction with gas chromatography, can be used for quantitative estimation of alkyl nitrates and nitrites in very low amounts.
  • Yoshimi Ohtani, Akihiko Yamagishi, Masatoshi Fujimoto
    1979 Volume 52 Issue 1 Pages 69-72
    Published: 1979
    Released: April 19, 2006
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    Kinetics of the hydrogenation of coordinated styrene and acrylonitrile in a rhodium-olefin complex RhClH2(ol)(PPh3)2 (ol=styrene or acrylonitrile) was studied by stopped-flow method and by the direct measurements of hydrogen-gas uptake. The equilibrium constant of the reaction RhCl(ol)(PPh3)2+H2\ ightleftharpoonsRhClH2(ol)(PPh3)2, K34, and the rate of the hydrogenation of the olefin in the complex RhClH2(ol)(PPh3)2, k45, were determined to be 3.2×103 mol−1 dm3 and 2.7 s−1 for styrene, and 3.5×102 mol−1 dm3 and 0.50 s−1 for acrylonitrile, respectively. The differences in the values for these two olefins were discussed. The data for cyclohexene were also briefly mentioned.
  • Tetsuro Majima, Yoshikane Kawasaki
    1979 Volume 52 Issue 1 Pages 73-78
    Published: 1979
    Released: April 19, 2006
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    Several dimethyllead(IV) complexes with ONNO quadridentate Schiff base ligands have been prepared. The spin-spin couplings between the lead nucleus and the azomethine proton of the ligands, 3J(207Pb–N=CH), as well as the lead-methyl proton couplings, 2J(207Pb–CH3), have been observed in various solvents. Both J values inclease with an increase in donor strength of the solvents. The mean excitation energy, the ΔE term in the Fermi contact term plays a dominating role for the lead-proton spin-spin coupling constants. Two methyl proton signals were, for the first time, found to be magnetically non-equivalent in the dimethyllead(IV) complex of sapr.
  • Tomoharu Ama, Takaji Yasui
    1979 Volume 52 Issue 1 Pages 79-83
    Published: 1979
    Released: April 19, 2006
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    A series of complexes or geometrical isomers, [Co(β-ala or gly)(en)2]2+, [Co(β-ala or gly)2(en)]+, [Co(β-ala or gly)(ox)2]2−, and [Co(β-ala or gly)2(ox)], were prepared and their 13C NMR spectra were measured. Assignments of their structures and 13C NMR signals were made. The β-alaninate carbons in the complexes resonate at 33.6±0.5, 38.3±0.6, and 183.0±1.5 ppm and the glycinate carbons at 46.3±1.3 and 187.4±1.4 ppm. The 13C chemical shifts of the mixed (β-alaninato)(glycinato) complexes consist of those of the corresponding isomers of bis(β-alaninato) and bis(glycinato) complexes.
  • Yusuke Yamamoto
    1979 Volume 52 Issue 1 Pages 84-89
    Published: 1979
    Released: April 19, 2006
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    Luminescence spectra of M3[Co(CN)6] (M=K, Rb, Cs), cis-K3Na2[Co(CN)4(SO3)2], and trans-Na5[Co(CN)4(SO3)2] were measured at 20 K. Single crystal luminescence spectra of the hexacyanocobaltates(III), centered at 14100–14200 cm−1, exhibited vibrational structure associated with three components, and the separation between the members of the progression was about 400 cm−1. Luminescence spectra of powdered cis-K3Na2[Co(CN)4(SO3)2] and trans-Na5[Co(CN)4(SO3)2] were structureless and broad centered at 13200 and 14400 cm−1, respectively. Comparison of these luminescence spectra with the corresponding spin-forbidden bands indicated that the 0-0 transition lies at 18300–18600 cm−1 for hexacyanocobaltates(III), at 16500–17000 cm−1 for cis-K3Na2[Co(CN)4(SO3)2], and at 17700–18200 cm−1 for trans-Na5[Co(CN)4(SO3)2]. The vibrational structure in luminescence spectra of hexacyanocobaltates(III) can be interpreted in terms of the ν8912 and ν13 ungerade skeletal modes, a lattice mode, and the totally symmetric ν2 vibrational mode. Analysis of the relative intensity of the vibrational structure in the luminescence spectra gave information about the change in the Co–C internuclear equilibrium distance from the ground state to the excited luminescent state. The relationship between luminescence and photochemical behavior of cobalt(III) complexes was also considered.
  • Akira Fuyuhiro, Kazuaki Yamanari, Yoichi Shimura
    1979 Volume 52 Issue 1 Pages 90-95
    Published: 1979
    Released: April 19, 2006
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    Two kinds of four-component solubility isotherms consisting of (Λ-[Co(ox)(en)2]+, Δ-[Co(ox)(en)2]+)–(Cl, X)–H2O, where X stands for Δ-[Co(edta)] or (R,R)-C4H5O6, have been determined experimentally at 25 °C. It has been found that neither double salt nor solid solution exists and no configurational activity is observed in these systems. The applications of these phase diagrams to the practical optical resolutions are discussed.
  • Takashi Katsura, Yutaka Tamaura, Gyong Sun Chyo
    1979 Volume 52 Issue 1 Pages 96-100
    Published: 1979
    Released: April 19, 2006
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    The oxidized Fe3O4–Fe2TiO4 solid solution with the spinel type structure was synthesized by means of ferrite methods at pH 9.0 and 65 °C. When the solid solution thus obtained was heated at 200 or 300 °C in air for 20 h, it was completely oxidized to form a ferromagnetic product, which retained the spinel type structure for Ti/Fetotal ratios from 0 to 0.5.
  • Shigekazu Kubo, Takashi Shibahara, Masayasu Mori
    1979 Volume 52 Issue 1 Pages 101-106
    Published: 1979
    Released: April 19, 2006
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    The IR spectroscopy of the μ-amido-μ-nitro complex, [(NH2,N02){Co(NH3)4}2]Cl4·2H2O obtained from normal and 18O-labeled [(NH2,O2){Co(NH3)4}2](NO3)4 has revealed that the O atom in the Co–N–O–Co chain comes from the O2 bridge of the starting complex, whereas the O atom attached to the N atom from outside the chain comes from the nitrite used in the bridge conversion, μO2→μNO2. A reaction mechanism involving N2O3 as the reacting species is proposed. The reaction of [(NH2,O2){Co(NH3)4}2]X3 with the nitrite in neutral solution gave a non-electrolytic μ-hyperoxo dicobalt complex, [(NH2,O2)Co2(NH3)4(NO2)4](I). Treatment of I with perchloric acid gave a triple-bridged complex, [(NH2,NO2,O2)Co2(NH3)4(NO2)2]+, which reproduces I when treated with sodium nitrite.
  • Kimiaki Imafuku, Makoto Ishizaka, Hisashi Matsumura
    1979 Volume 52 Issue 1 Pages 107-110
    Published: 1979
    Released: April 19, 2006
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    5-Hydroxy-2-hydroxymethyl-4-pyridone and its N-methyl, N-ethyl, and N-phenyl derivatives were prepared from kojic acid. The UV spectra in neutral, acid, and alkaline solutions showed that the neutral species and the conjugate acids existed in the pyridone and the pyridine form, respectively. The conjugate bases may exist in both forms. The acid dissociation constants and the halochromism have been measured and discussed.
  • Kimiaki Imafuku, Kumio Takahashi, Hisashi Matsumura
    1979 Volume 52 Issue 1 Pages 111-113
    Published: 1979
    Released: April 19, 2006
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    Acid dissociation constants and UV and NMR spectra of a series of 6-substituted 3-hydroxy-1-methyl-4-pyridones have been measured. The acid dissociation constants have been analyzed in terms of the Hammett equation to give linear relationships, with ρ=1.16 for the conjugate acids and ρ=1.06 for the neutral compounds. Halochromism in the UV spectra gave the equation: Δ\ ildeν=689 pKa−9399, and the Hammett plots of the chemical shifts of the 2-H, 5-H, and CH3 protons gave linear relationships, with ρ=1.78, 2.56, and 1.39, respectively.
  • Akio Yasuhara, Keiichiro Fuwa
    1979 Volume 52 Issue 1 Pages 114-117
    Published: 1979
    Released: April 19, 2006
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    Volatile and odorous components were isolated from anaerobically or aerobically digested liquid swine manure by direct solvent-extraction and flash-distillation under reduced pressure. The concentrations of indole, oxindole, dimethylsulfoxide, phenol, and a few carboxylic acids increased, and o-aminoacetophenone decreased during digestion. Alkaline components were not so important for the odor. Offensive odor was formed by mixing phenols and carboxylic acids. Complete aeration resulted in a remarkable decrease of lower carboxylic acids.
  • Seiichiro Ogawa, Isamu Kasahara, Tetsuo Suami
    1979 Volume 52 Issue 1 Pages 118-123
    Published: 1979
    Released: April 19, 2006
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    DL-Validamine and its amino deoxy and deoxy analogs were synthesized as the acetyl derivatives from endo-7-oxabicyclo[2.2.1]hept-5-ene-2-carboxylic acid, the Diels-Alder adduct of acrylic acid and furan.
  • Sumihiko Okuyama, Daisuke Uemura, Yoshimasa Hirata
    1979 Volume 52 Issue 1 Pages 124-126
    Published: 1979
    Released: April 19, 2006
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    High performance liquid chromatographic analyses of individual bile acids (cholic, chenodeoxycholic, deoxycholic, and lithocholic acids), free and conjugated with glycine and taurine, are described. The analyses of the free and glycine-conjugated bile acids are based on the esterification of the carboxyl group of bile acids with O-(p-nitrobenzyl)-N,N′-diisopropylisourea(PNBDI). The bile acids in the biological samples were extracted by an Amberlite XAD-2 column, and separated by DEAE-Sepharose CL-6B into free, glycine and taurine-conjugated bile acids. After separation, the free and glycine-conjugated bile acids were directly esterified with PNBDI. Taurine-conjugated bile acids are unable to be esterified with PNBDI, the bile acids were hydrolyzed with NaOH to produce the free bile acids, and then esterified. The p-nitrobenzyl ester of bile acids has a characteristic ultraviolet absorption. Consequently the compounds were separated into the individual bile acids by high performance liquid chromatography, and detected by an UV-detector. An analysis of the individual bile acids in human bile is given for an example.
  • Tadashi Masamune, Hajime Matsue, Hisashi Murase
    1979 Volume 52 Issue 1 Pages 127-134
    Published: 1979
    Released: April 19, 2006
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    The synthesis of cis-2-ethyl-8-formyl-3,4,7,8-dihydro-2H-oxocin-3-one and its derivatives, key intermediates for synthesis of laurencin, from methyl 2-ethyl-2,5-dihydro-2-furoates is described. The structure and configuration of these compounds and the synthetic intermediates are defined clearly on the basis of the chemical and spectral evidence.
  • Tadashi Masamune, Hisashi Murase, Hajime Matsue, Akio Murai
    1979 Volume 52 Issue 1 Pages 135-141
    Published: 1979
    Released: April 19, 2006
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    Transformation of the title starting material into (±)-laurencin, which implies synthesis of the natural product, is described. The structure and configuration of synthetic intermediates are defined on the basis of the spectral evidence.
  • Shin-ichi Kamiyama, Tetsuo Kimura, Akira Kasahara, Taeko Izumi, Mitsug ...
    1979 Volume 52 Issue 1 Pages 142-145
    Published: 1979
    Released: April 19, 2006
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    The reaction between (dimethylaminomethyl)ruthenocene with lithium tetrachloropalladate(II) in the presence of sodium acetate gave di-μ-chloro-bis[2-(dimethylaminomethyl)ruthenocenyl]dipalladium(II) (2). The σ-bonded structure of 2 has been confirmed by IR analysis and the reactions of 2 with triphenylphosphine, thallium(I) acetylacetonate, and lithium aluminum deuteride. The reactions of chloro [2-(dimethylaminomethyl)ruthenocenyl](triphenylphosphine)palladium(II) with carbon monoxide and 2 with methyl vinyl ketone, phenyl vinyl ketone, and styrene have been examined. 1,2-Disubstituted ruthenocene derivatives have been obtained in higher yields than those of the corresponding ferrocene derivatives.
  • Minoru Kubota, Takakazu Yamamoto, Akio Yamamoto
    1979 Volume 52 Issue 1 Pages 146-150
    Published: 1979
    Released: April 19, 2006
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    Alkoxocopper and phenoxocopper complexes ROCu (PPh3)n (PPh3=triphenylphosphine; n=1 for R=n-C3H7 or i-C3H7; n=2 for R=CH3, C2H5, CH2=CHCH2, C6H5CH2, or C6H5) react with esters undergoing exchange of the RO group with carboxylic esters. The alkoxocopper and phenoxocopper complexes are found to be excellent catalysts for the trans-esterification of carboxylic esters, dimethyl carbonate, and trimethyl phosphite with alcohols and phenols. A comparison of the ability of the isopropoxocopper complex as trans-esterification catalyst with that of aluminum isopropoxide and titanium isopropoxide shows the superiority of the isopropoxocopper complex. The rate of trans-esterification between p-nitrophenyl acetate and phenol follows the second-order rate law R=k[p-nitrophenyl acetate][phenol], the activation energy of the reaction being estimated to be 12.4 kcal/mol. A mechanism comprising a nucleophilic attack on the copper-bound carbonyl group of the ester by alcohol is proposed.
  • Takashi Toda, Katsuhiro Saito, Toshio Mukai
    1979 Volume 52 Issue 1 Pages 151-155
    Published: 1979
    Released: April 19, 2006
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    Reaction of dimethyl trans-spiro[2.6]nona-4,6,8-trien-1,2-dicarboxylate with phenyllithium afforded trans-1,2-bis(hydroxydiphenylmethyl)spiro[2.6]nona-4,6,8-triene (2) in a good yield. Spirotriene 2 is very sensitive to acids and gave 8-(2,2-diphenylvinyl) heptafulvene accompanied with a quantitative amount of benzophenone by acid treatments. Although 2 is stable to basic reagents, upon treating with sodium hydride, 2 afforded 11-hydroxydiphenylmethyl-8-oxa-9-diphenyltricyclo[5.4.0.01,10]undeca-2,4-diene, and its double bond isomers. Mechanisms of the above reactions are discussed.
  • Kin-ya Akiba, Hiroaki Shiraishi, Naoki Inamoto
    1979 Volume 52 Issue 1 Pages 156-159
    Published: 1979
    Released: April 19, 2006
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    Reactions of 3-methyl-2,3-dihydrobenzothiazole-2-thione (1) and 3-methyl-2-(methylthio)benzothiazoliumiodide with Grignard reagents gave 2,2-disubstituted 3-methyl-2,3-dihydrobenzothiazole (2) as a major product as well as 2,2′-disubstituted 3,3′-dimethyl-2,2′,3,3′-tetrahydrobi(2-benzothiazolyl) (3). Reactions of 1 with organolithiums gave 2 as a major product. The results demonstrate that the formation of 3 is due to the presence of transition metals as an impurity in magnesium.
  • Hiroyuki Nakazumi, Teijiro Kitao
    1979 Volume 52 Issue 1 Pages 160-163
    Published: 1979
    Released: April 19, 2006
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    4H-1-Benzothiopyran-4-ones (thiochromones) and isomeric 2H-1-benzothiopyran-2-ones (thiocoumarins) have been allowed to react with dimethyl sulfate (DMS) to study the differences in reactivity on methylation. Methylation of 2-methyl (thiochromones) with DMS afforded the blue colored dimerization products, 4-(4-methoxy-1-benzothiopyran-2-ylidenemethyl)-2-methyl-1-benzothiopyrylium perchlorates, while that of 7-methoxy-4-methyl(thiocoumarin) gave the O-methylated yellow salt, 2,7-dimethoxy-4-methyl-1-benzothiopyrylium perchlorate. Methylations of oxa analogues (coumarins) and aza analogues (2-quinolones) of thiocoumarins with DMS have also been examined. It has been found that the ease of formation of methylation products is affected by the hetero atom and carbonyl group.
  • Eri Akiyama, Masahiro Tada, Takahiko Tsuyuki, Takeyoshi Takahashi
    1979 Volume 52 Issue 1 Pages 164-169
    Published: 1979
    Released: April 19, 2006
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    Dry ozonation of friedelane afforded 18β,19β-epoxyfriedelane, 19-oxofriedelane, 16-oxofriedelane, 21-oxofriedelane, friedelin, and a new compound, 15-oxofriedelane. Friedelin, on dry ozonation, gave 3,16-dioxofriedelane, 3,19-dioxofriedelane, and new compounds, 18β,19β-epoxyfriedelan-3-one and 3,15-dioxofriedelane. It was shown that the oxidation occurred at D and E rings regioselectively in the dry ozonation.
  • Toshihiro Kamada
    1979 Volume 52 Issue 1 Pages 170-174
    Published: 1979
    Released: April 19, 2006
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    A novel and convenient method for the synthesis of the 8,9,10,11-tetrahydro-7H-cycloocta[de]naphthalene ring system is described. Reaction of diethyl acetonedicarboxylate and 1,8-bis(bromomethyl)naphthalene gave the eight-membered pericyclized compound, diethyl 9-oxo-8,9,10,11-tetrahydro-7H-cycloocta[de]naphthalene-8,10-dicarboxylate, which was then converted, through several steps, into various kinds of 8- and 10-methyl-substituted 8,9,10,11-tetrahydro-7H-cycloocta[de]naphthalenes and their 9-oxo derivatives, as well as the unsubstituted compounds, 8,9,10,11-tetrahydro-7H-cycloocta[de] naphthalene and 8,9,10,11-tetrahydro-7H-cycloocta[de]naphthalen-9-one. The hydrocarbon, 8,8,10,10-tetramethyl-8,9,10,11-tetrahydro-7H-cycloocta[de]-naphthalene was prepared from 8,8,10,10-tetrakis(tosyloxymethyl)-8,9,10,11-tetrahydro-7H-cycloocta[de]naphthalene.
  • Renji Okazaki, Masako Watanabe, Naoki Inamoto
    1979 Volume 52 Issue 1 Pages 175-180
    Published: 1979
    Released: April 19, 2006
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    Photolysis of (E)-1-hydroxyimino-2,4,5-tri-t-butyl-6-methyl-2,4-cyclohexadiene (1) and the corresponding (Z)-isomer in methanol, benzene, or pentane afford 1,3,5-tri-t-butyl-5-cyano-1,3-cyclohexadiene (3), 5-t-butyl-7-cyano-2,2,3,8,8-pentamethyl-3,4,6-nonatriene (4), 5-t-butyl-3-cyano-2,2,7,8,8-pentamethyl-3,4,6-nonatriene (5), 5-t-butyl-7-cyano-2,3,3,8,8-pentamethyl-1,4,6-nonatriene (6), 5-t-butyl-3-cyano-7-methoxy-2,2,7,8,8-pentamethyl-3,5-nonadiene (7), 5-t-butyl-7-cyano-7-methoxy-2,2,3,8,8-pentamethyl-3,5-nonadiene, and 2,4-di-t-butyl-6-cyano-7,7-dimethyl-1,3,5-octatriene (9). The presence of an oxaziridine in the reaction mixture has been confirmed by iodometry. The photoreaction in the presence of 1,3-pentadiene or oxygen gives essentially the same results, suggesting the involvement of the singlet excited state in these photoreactions. Thermal Beckmann rearrangement of 1 has been conducted for comparison to give only 6, 7, and 9. The photochemical formation of 39 has been rationalized in terms of the “free” cyclopentadienyl cation formed by ionic α-cleavage of the oxime. Photoreaction of 1-hydroxyimino-2,4,6-tri-t-butyl-2,4-cyclohexadiene with one alkyl group at 6-position gives 5-t-butyl-7-cyano-2,3,8,8-tetramethyl-1,4,6-nonatriene, 5-t-butyl-3-cyano-8-methoxy-2,2,7,8-tetramethyl-4,6-nonadiene, 5-t-butyl-7-cyano-2-methoxy-2,3,8,8-tetramethyl-3,5-nonadiene, and 1,3-di-t-butyl-5-cyano-3-methoxy-6,6-dimethyl-1,4-heptadiene.
  • Takashi Sugimoto, Sadao Matsuura
    1979 Volume 52 Issue 1 Pages 181-183
    Published: 1979
    Released: April 19, 2006
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    2-Amino-4-hydroxy-6-[(1S)-1, 2-dihydroxyethyl] pteridine has been synthesized by the condensation of 2,4,5-triamino-6-hydroxypyrimidine and D-threose phenylhydrazone, followed by oxidation of the intermediate carried out by adding the condensate to a mixture of K3[Fe(CN)6], KI, and H2O2 in an acidic solution. The 6-(1R)-1,2-dihydroxyethyl isomer and the 6-(1R) [and (1S)] -1-hydroxyethyl analogues have also been synthesized in a similar way. By applying the present method, biopterin has been obtained in 28% yield.
  • Mitsuru Nakayama, Shuzo Shinke, Yoichi Matsushita, Susumu Ohira, Shuic ...
    1979 Volume 52 Issue 1 Pages 184-185
    Published: 1979
    Released: April 19, 2006
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    Allylic oxidation of methyl 2-alkenoates with chromium trioxide in a mixture of acetic anhydride and acetic acid afforded methyl 4-oxo-2-alkenoates.
  • Kiyoyuki Yamada, Shunichi Manabe, Yoshinori Kyotani, Masaaki Suzuki, Y ...
    1979 Volume 52 Issue 1 Pages 186-190
    Published: 1979
    Released: April 19, 2006
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    Five bicyclo[3.3.1]nonan-2-ones, two known (1, 3) and three new ones (2, 4, 5) were prepared. The hydrogen-deuterium exchange reaction at the bridgehead position of the bicyclo[3.3.1]nonan-2-one system was examined under mild basic conditions (2 M NaOMe-MeOD, 33 °C, 22 h) using these five bicyclo[3.3.1]nonan-2-ones. Virtually no deuteration took place at the bridgehead in each case of the bicyclic ketones (1, 2, 3, 4), whereas one deuterium was incorporated into the bridgehead of the ketone (5). 13C NMR spectroscopy was employed for the unambiguous determination of the site(s) of deuteration in all cases studied. The enhanced bridgehead acidity of (5) could be explained in terms of the locked boat conformation of the cyclohexanone ring contained in (5).
  • Hitomi Suzuki, Tadashi Mishina, Terukiyo Hanafusa
    1979 Volume 52 Issue 1 Pages 191-197
    Published: 1979
    Released: April 19, 2006
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    The reaction in acetic acid of hexamethylbenzene and hexamethylbenzene-d18 with nitric acid in the dark has been investigated under various conditions using a high-pressure liquid chromatographic method. Pentamethylbenzyl nitrate, pentamethylphenylnitromethane, pentamethylbenzyl acetate, and pentamethylbenzyl alcohol were formed immediately after the mixing of reactants; their relative amounts remained almost unchanged up to nearly 50% conversion. The addition of sodium nitrite gave little influence on the composition of the product mixture, while urea was found to depress somewhat the formation of nitromethane. In the presence of lithium nitrate, the reaction was modestly accelerated and the nitrate formation seems to be slightly favored over the nitromethane formation. Hexamethylbenzene-d18 reacted with nitric acid at the same rate as the non-labeled hydrocarbon did, but the benzyl nitrate/phenylnitromethane ratio in the product mixture was considerably higher in the former. Based on the quantitative data obtained, the mechanism for the side-chain substitution has been discussed in terms of the SN1′ pathway: nitronium ion makes an ipso attack on the substrate to form the arenium ion, which releases a proton from the activated methyl group para to the site of attack to give the 3-methylene-6-nitro-1, 4-cyclohexadiene intermediate (7). Heterolytic fission of the C–N bond in 7 will form a benzyl cation-nitrite anion pair, which recombines at the benzylic carbon atom via a C–N bond or via a C–O bond, giving benzyl nitrite or phenylnitromethane, respectively. Benzyl nitrite will be further converted into benzyl nitrate and benzyl alcohol, while benzyl acetate will arise from the incorporation of solvent molecules into the ion-pair.
  • Shimpei Aburaki, Mitsuhiro Kinoshita
    1979 Volume 52 Issue 1 Pages 198-203
    Published: 1979
    Released: April 19, 2006
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    An improved synthesis of antimycin A3 was accomplished by a suitable lactonization of 3-O-benzyl or 3-O-isovaleryl derivative (10a or 10b) of (2R, 3R, 4S)-4-(N-benzyloxycarbonyl-L-threonyloxy)-2-butyl-3-hydroxypentanoic acid, which was synthesized by starting from the corresponding 3-O-benzyl or 3-O-isovaleryl derivative (4a or 4b) of methyl 2-C-butyl-2, 5-dideoxy-β-L-arabinofuranoside, respectively. Acid hydrolysis of 4a or 4b followed by reduction with sodium borohydride afforded 3-O-benzyl or 3-O-isovaleryl-1, 3,4-pentanetriol (5a or 5b), respectively. Tritylation of 5a or 5b followed by succesive 4-O-acylation with N-benzyloxycarbonyl-O-t-butyl-L-threonine, detritylation, oxidation with chromium trioxide-acetic acid-pyridine, and de-t-butylation gave the hydroxy ester acid 10a or 10b, respectively. Lactonization of 10a or 10b through its 2-pyridinethiol ester 11a or 11b activated with silver perchlorate afforded the corresponding nine-membered dilactone derivative 12a or 12b in 33 or 13% yield, respectively. Removal of N,O-protecting groups of 12a by hydrogenolysis, followed by successive N- and O-acylation gave the antimycin A3 precursor, (3S, 4R, 1R, 8R, 9S)-3-(2-benzyloxy-3-nitrobenzoylamino) -4, 9-dimethyl-7-butyl-8-isovaleryloxy-1, 5-dioxonane-2, 6-dione derived from 12b.
  • Toshizumi Tanabe, Kiyoshi Yamauchi, Masayoshi Kinoshita
    1979 Volume 52 Issue 1 Pages 204-207
    Published: 1979
    Released: April 19, 2006
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    The reactions of thymidine, deoxyuridine, and deoxycytidine with trimethyl phosphate (TMP) were studied in a homogeneous water solution at 37–60 °C and pH 7–10. Three pyrimidine deoxynucleosides were methylated mainly at the N-3 position to afford their 3-methyl derivatives. The methylation rate at the N-3 position was found to be dependent on the pH of reaction medium. At pH 10, thymidine and deoxyuridine were methylated much faster than deoxycytidine, the tendency being reversed at pH 7.
  • Hisashi Takei, Nobuyoshi Yasuda, Hidetsugu Takagaki
    1979 Volume 52 Issue 1 Pages 208-211
    Published: 1979
    Released: April 19, 2006
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    3,7-Dihydroxy- and 3-substituted 7-hydroxypyrazolo[4,3-d]pyrimidines were synthesized from diethyl oxaloacetate and ethyl acylpyruvates via ethyl 4-amino-5-oxo-2-pyrazoline-3-carboxylate hydrochloride and ethyl 5-substituted 4-amino-3-pyrazolecarboxylates, respectively.
  • Takashi Matsumoto, Shuji Usui
    1979 Volume 52 Issue 1 Pages 212-215
    Published: 1979
    Released: April 19, 2006
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    The Wittig reaction of (R)-(−)-α-cyclocitral with (3-isopropyl-4-methoxybenzyl)-, (4-isopropyl-3-methoxybenzyl)-, and (3-methoxybenzyl) triphenylphosphonium chloride afforded the styryl derivatives which were partially hydrogenated to the corresponding dihydro derivatives (18, 26, and 27). Intramolecular cyclization of 18 and 26 with anhydrous aluminium chloride followed by demethylation with boron tribromide gave (+)-ferruginol and (+)-sempervirol. The similar cyclization of 27 gave (+)-13-methoxypodocarpa-8, 11, 13-triene. This was reduced with lithium in liquid ammonia in the presence of ethanol and then treated with dilute hydrochloric acid to give (+)-podocarpa-8(14)-en-13-one, a versatile intermediate for natural diterpene synthesis.
  • Jiro Tsuji, Kazuyuki Kasuga, Takashi Takahashi
    1979 Volume 52 Issue 1 Pages 216-217
    Published: 1979
    Released: April 19, 2006
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    Ethyl 2-acetyl-4, 9-decadienoate, easily obtained by the palladium catalyzed telomerization of butadiene with ethyl acetoacetate, was selectively hydrogenated to ethyl 2-acetyl-9-decenoate using RuCl2 (PPh3)3 as a catalyst. Deacetylation, followed by hydrolysis produced 4-decenoic acid, which was converted into acid chloride. The AlCl3-promoted cyclization gave 2-pentyl-2-cyclopentenone, from which methyl dihydrojasmonate was prepared.
  • Toshiro Aratani, Shigeki Yasuhara, Hitoshi Matoba, Takeo Yano
    1979 Volume 52 Issue 1 Pages 218-222
    Published: 1979
    Released: April 19, 2006
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    A continuous wastewater treatment system was developed for the Lime Sulfurated Solution Process which had already been tested in a batch, stirred tank and ascertained to be an effective chemical precipitation process. The removability of heavy metals was investigated with the continuous treatment system, consisting of a plant composed of H2S desorber, reactor, thickener, sand filter, and H2S desorber. The sulfide ion dissolved in treated water was desorbed as H2S by a mixed gas of air and CO2 and recycled in the reactor to precipitate heavy metals. It has been found that: (1) by the recycling use of H2S, the continuous treatment system can remove heavy metals with less coagulant than in the batch, stirred vessel, (2) desorption of the dissolved sulfide ion by the mixed gas decreases the sulfide ion concentration in the treated water below 0.2 ppb, and (3) the conditions for the removal of heavy metals can be detected immediately by a sulfide ion electrode meter.
  • Hitoshi Takeshita, Kozo Tajiri, Isao Kouno
    1979 Volume 52 Issue 1 Pages 223-224
    Published: 1979
    Released: April 19, 2006
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    Pyrolysis of 2-[(E)-4-bromo-3-butenyloxy]tropone and 2-[(E)-4-bromo-2-methyl-2-butenyloxy]tropone produced 3-methyl-3-vinyl-2,3-dihydro-8H-cyclohepta[b]furan-8-one and 3-isopropylidene-2,3-dihydro-8H-cyclohepta [b]furan-8-one, which established the involvement of 3,3-sigmatropy for furotropone formation.
  • Kenjiro Kondo, Masuo Yagi
    1979 Volume 52 Issue 1 Pages 225-226
    Published: 1979
    Released: April 19, 2006
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    The effects of various inorganic additives with and without dipole moments on the product yield distributions have been examined in the CH4–H80mBr and CH4-H82mBr systems. Indications were that the ion-clusters formed in the reactions of IT-activated 80Br and 82Br play an important role in determining individual product yield distributions.
  • Kenji Fujiwara, Shun-ichi Ikawa, Masao Kimura
    1979 Volume 52 Issue 1 Pages 227-228
    Published: 1979
    Released: April 19, 2006
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    Far-infrared absorptions of some non-dipolar liquid mixtures have been observed. The changes of the intensities with mixing ratio were examined on the basis of a formula derived for the difference between absorption intensities before and after mixing, to get information about the mixing state.
  • Akio Furusaki, Shinsei Gasa, Takeshi Matsumoto
    1979 Volume 52 Issue 1 Pages 229-230
    Published: 1979
    Released: April 19, 2006
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    The molecular structure of the title compound has been determined by means of the X-ray method. The A, B, and C rings take half-chair, chair, and chair conformations, respectively, while the heterocyclic ring is of envelope form.
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