Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 53 , Issue 9
Showing 1-50 articles out of 63 articles from the selected issue
  • Haruo Nakayama, Masayuki Hashimoto
    1980 Volume 53 Issue 9 Pages 2427-2433
    Published: 1980
    Released: April 19, 2006
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    A new method for examining the ability of a given substance to form a hydrate with the same structure as that of a reference substance has been established. By using this method, for a series of alcohols ranging from methyl alcohol to pentyl alcohol, including their isomers, the ability to form a clathrate hydrate of either Structure I or Structure II has been investigated. It has been found that: (1) methyl alcohol has the ability to form both Structure I and II hydrates; (2) ethyl alcohol has the ability to form a Structure II hydrate; (3) all C3-alcohols (propyl, isopropyl, allyl, and propargyl alcohol) can actually form Structure II hydrates with relatively high (around −10 °C) incongruent melting points, and (4) among the C4- and C5-alcohols, only t-butyl alcohol has the ability to form a Structure II hydrate. However, it is uncertain for methyl and ethyl alcohols whether they actually can form such hydrates even in the absence of a reference substance. These results strongly suggest that the size and/or shape limitation plays an important role in the formation of alcohol hydrates with a gas-hydrate structure, just as has been found for the formation of ether and ketone hydrates.
  • Seiji Yoshimura, Akira Katagiri, Yasuo Deguchi, Shiro Yoshizawa
    1980 Volume 53 Issue 9 Pages 2434-2436
    Published: 1980
    Released: April 19, 2006
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    The formation of the tetracyanocuprate(II) ion (Cu(CN)42−), which was expected as a reaction intermediate in the anodic oxidation of the cyanide ion in the presence of the copper ion, has been investigated by means of ESR measurement. When a potassium cyanide solution containing a small amount of copper(I) cyanide was electrolyzed, an intermediate copper(II) species was found at the anode in the dissolved state. The ESR spectrum of the intermediate in the solidified state was obtained by freezing the solution in the resonant cavity. The intermediate was identified as Cu(CN)42− by a comparison of its spectrum to that of Cu(CN)42− already reported by other authors. When the ratio of the total copper(I) concentration to the total cyanide concentration in the solution was not too small, solid copper(II) cyanide was deposited on the anode during electrolysis.
  • Seiji Yoshimura, Akira Katagiri, Yasuo Deguchi, Shiro Yoshizawa
    1980 Volume 53 Issue 9 Pages 2437-2442
    Published: 1980
    Released: April 19, 2006
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    The kinetics and mechanism of the decomposition of the tetracyanocuprate(II) ion (CuII(CN)42−) have been investigated by ESR measurements. Aqueous solutions of potassium cyanide with a small amount of copper(I) cyanide were electrolyzed in a cell the platinum anode of which was set in the resonant cavity of an ESR spectrometer. Since CuII(CN)42−, which is formed as an intermediate, gives a definite ESR spectrum, its concentration in the anode compartment is estimated from the intensity of the first-derivative spectrum at a fixed magnetic field. From the decay curves of the ESR intensity after the steady-state electrolysis currents have been switched off, a rate equation for the decomposition of CuII(CN)42− is derived; v=k0[CuII(CN)42−]2⁄[CN]2, where k0 is calculated to be 74 mol·dm−3·s−1 at 25 °C. This rate equation is also confirmed by ESR measurements during steady-state electrolysis, where the value of k0=60 mol·dm−3·s−1 is obtained. On the basis of the kinetics, two possible mechanisms are proposed: the formation of CuII(CN)3, followed by the rate-determining bimo-lecular reaction of CuII(CN)3 to give 2CuI(CN)2+(CN)2 (Mechanism A), and the formation of a binuclear complex, CuII2(CN)62−, followed by the rate-determining decomposition of CuII2(CN)62− to give 2CuI(CN)2+ (CN)2 (Mechanism B). The kinetics and the mechanism are compared with those of the chemical reaction between the copper(II) ion and the cyanide ion.
  • Shigeru Tsunashima, Jun-ichi Hamada, Mitsuhiro Hotta, Shin Sato
    1980 Volume 53 Issue 9 Pages 2443-2447
    Published: 1980
    Released: April 19, 2006
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    The photolysis of HN3 was studied in liquid ethane, propane, and isobutane at the temperature of Dry Ice–methanol. In the reaction mixtures, quaternary ammonium salts were formed between the basic products and HN3. The products were analyzed after having been passed through a trap containing NaOH, in which the salts were decomposed. The main products observed were nitrogen and amines: ethylamine from ethane, propyl– and isopropylamine from propane, and i-butyl, and t-butylamine from an isobutane solution. Ammonia and hydrogen were also formed as minor products. Possible reaction mechanisms are discussed. It is suggested that about 80% of the singlet NH is inserted into the C–H bond of paraffin to form amine and that 20% of it is deactivated to the ground triplet state by the reactions with paraffin. The relative efficiencies of the insertion into primary, secondary, and tertiary C–H bonds were estimated to be 1.0, 1.9, and 2.3 respectively.
  • Koichi Kobayashi, Yoshiko Shimizu, Tsunetaka Sasaki
    1980 Volume 53 Issue 9 Pages 2448-2450
    Published: 1980
    Released: April 19, 2006
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    The flotation of Cd2+ ions was investigated in the presence and absence of Zn2+ ions. It was found that the flotation efficiency of Cd2+ ions in the Cd2+–anionic surfactant system is markedly small in the presence of Zn2+ ions, but the flotation efficiency of Cd2+ ions in the Cd2+–bentonite–cationic surfactant system (adsorbing particle flotation) decreased only slightly in the presence of Zn2+ ions. The flotation efficiency in the latter case was further increased by the addition of 3 ppm of polyacrylamide. The doubling of the flotation reagents and time did not effectively increased the flotation efficiency of Cd2+ ions in the presence of Zn2+ ions, but the two-stage flotation did. It was confirmed that the adsorbing particle flotation of Cd2+ ions would be an excellent method in the presence of Zn2+ ions.
  • Hatsuho Uedaira, Hisashi Uedaira
    1980 Volume 53 Issue 9 Pages 2451-2455
    Published: 1980
    Released: April 19, 2006
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    Thermal denaturation of lysozyme (hen egg-white) in aqueous sugar solution was studied by DSC measurements at pH 5 and by CD measurements at pH 2.12. All of the sugars investigated show a stabilizing influence on the native conformation. The effect of sugars on the transition temperature of lysozyme almost linearly increased with the increase of the numbers of equatorial hydroxyl groups per molecule of sugars. The ellipticity of the solutions at 294 nm of lysozyme and glucose or arabinose was additive in the value of each component at pH 5. The effect of sugars in stabilizing the protein structure may be due to the intensification of the hydrophobic interactions inside the protein molecule.
  • Shi-aki Hyodo, Tsunetake Fujiyama
    1980 Volume 53 Issue 9 Pages 2456-2460
    Published: 1980
    Released: April 19, 2006
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    The depolarization degree of a molecule having a Td symmetry was expressed in terms of the mean square fluctuation of the local field which is felt by a molecule in the condensed phase. By the use of the mean square amplitude values observed by the X-ray diffraction method, the depolarization degree of liquid carbon tetrachloride was calculated to be 0.0021, which agrees well with the observed value of 0.0039±0.0002.
  • Yorihiko Sasaki, Shigehiro Konaka, Masao Kimura
    1980 Volume 53 Issue 9 Pages 2461-2462
    Published: 1980
    Released: April 19, 2006
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    Some new relations connecting the molecular electron densities and the intensities of electrons and X-rays scattered by gases have been derived by integrating analytically the scattered intensities multiplied by some functions of the momentum transfer, s, over ds.
  • Hitofumi Taniguchi, Tatsuo Masuda, Kazuo Tsutsumi, Hiroshi Takahashi
    1980 Volume 53 Issue 9 Pages 2463-2465
    Published: 1980
    Released: April 19, 2006
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    Solid super acids were prepared by the reaction of gaseous antimony pentafluoride with silica–alumina and heats of adsorption of ammonia on their surfaces were measured. Solid super acids gave about 170 kJ/mol of an initial differential heat of adsorption and their adsorption energies were mainly distributed in the vicinity of 137 kJ/mol, while the initial differential heat of adsorption on original silica–alumina was about 150 kJ/mol and its adsorption energy was chiefly distributed in the vicinity of 117 kJ/mol. Therefore, it was shown that solid super acid had stronger, more homogeneous and much more acid sites than original silica–alumina.
  • Akinori Inoue, Nobuyuki Nishi, Minoru Kinoshita, Nozomu Ebara
    1980 Volume 53 Issue 9 Pages 2466-2467
    Published: 1980
    Released: April 19, 2006
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    The triplet-triplet energy transfer between like molecules was investigated for the system of quinoxaline in ethanol by using the method of optical detection of zero-field magnetic resonance at 1.4 K. The concentration dependence of the spin state population indicates that the energy transfer between quinoxaline molecules takes place at concentrations higher than about 2×10−2 mol/dm3.
  • Michiro Hayashi, Jun Nakagawa, Yasunori Aguni
    1980 Volume 53 Issue 9 Pages 2468-2471
    Published: 1980
    Released: April 19, 2006
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    The microwave spectra of propyl silane and its four deuterated species were measured. The structure of the antiperiplanar isomer was so obtained as to reproduce the observed moments of inertia. The dipole moment and its direction were determined by Stark-effect measurements of several low J transitions.
  • Kenji Yokoyama, Ryoichi Nakagaki, Junko Nakamura, Kiyoshi Mutai, Sabur ...
    1980 Volume 53 Issue 9 Pages 2472-2475
    Published: 1980
    Released: April 19, 2006
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    Photo-Smiles rearrangement reaction of N-[ω-(p-nitrophenoxy)alkyl]aniline was studied by measuring the absorption spectra of transient species. Two intermediates A and B were observed and were assigned to a solvated ion pair and the Meisenheimer complex, respectively. The reaction scheme, starting material→intramolecular charge transfer on excitation→AB→final product, was derived from the relative yields and lifetimes of A and B as well as from the effects of solvent polarity, of triethylamine and oxygen, and of the alkyl chain length on each step of reaction.
  • Shun-ichi Ishikawa, Junko Nakamura, Saburo Nagakura
    1980 Volume 53 Issue 9 Pages 2476-2480
    Published: 1980
    Released: April 19, 2006
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    Photochemistry of [2.2]paracyclophane in glassy solvents at 77 K was studied. With irradiation, a species in which two benzyl radicals are linked together with an ethylene bridge was produced. From the ESR study, the radicals were found to form the benzyl radical pair in harder solvents. The emission spectrum and the emission lifetime of the radical species showed remarkable dependence on the solvent viscosity. In harder solvents, a new broad emission was observed on the longer wavelength side of the structured emission of the benzyl radical. From the studies of the excitation spectrum and the emission lifetime, this broad band was concluded to be the intramolecular excimer fluorescence of the radical pair. The photo-reaction of [2.2]paracyclophane was found to be biphotonic, occurring from a higher triplet state excited via the lowest triplet state.
  • Eiko Kai, Tomoko Misawa, Kichisuke Nishimoto
    1980 Volume 53 Issue 9 Pages 2481-2488
    Published: 1980
    Released: April 19, 2006
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    CNDO/2 calculations of pentaammine complexes, [M(NH3)5X] (both low and high spin states), where M=Co2+, Co3+, Fe2+, and Fe3+, and X=FH, OH2, CO, NH3, pyridine, OH, F, and CN, have been carried out in order to investigate the mutual influence between ligands. The present calculation shows that the σ-type mutual influence is remarkably affected by the oxidation number and the spin state of the metal ion and scarecely affected by the number of d electron (d electron configuration). Furthermore, the calculated results show the metal-ligand bond distance of a complex in the low spin state should be shorter than that in the high spin state.
  • Kenji Yokoyama, Yoshitaka Tajima, Masao Tahara, Shiro Maeda
    1980 Volume 53 Issue 9 Pages 2489-2492
    Published: 1980
    Released: April 19, 2006
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    The resonance Raman spectra of some Würster’s cation dimers were measured in alcohol solution at 201 K and in glassy matrix at 77 K. The spectra of the dimer of p-phenylenediamine cation showed the resonance enhancement of the Raman line assigned to the intermolecular stretching vibration and supported the D2h symmetry for the dimer. However, for the dimer of 2,3,5,6-tetramethyl-p-phenylenediamine cation and N,N-dimethyl-p-phenylenediamine cation, it was supposed that D2h symmetry was broken down in alcohol solution and in glassy matrix, because the dimers had two Raman lines in the region of the intermolecular vibration.
  • Haruo Nakayama, Kazuo Itoh, K\={o}z\={o} Shinoda, Egon Matijevic
    1980 Volume 53 Issue 9 Pages 2493-2498
    Published: 1980
    Released: April 19, 2006
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    Precipitation and microflotation of egg albumin and of hemoglobin was studied as a function of pH in the presence of dioctadecyldimethylammonium chloride (DOAC). The “DOAC concentration-pH” stability domains for both protein solutions (0.05 wt%) exhibited similar boundaries. Efficient separation by precipitation (more than 80% after 24 h) occurs at pH>5.0 for albumin and at pH>6.3 for hemoglobin. The same amount of removal by microflotation required 5 min under otherwise similar conditions. The DOAC concentration for optimal separation of proteins (from 0.05 wt% solutions) is 0.02 wt% at pH 6–8 for albumin and 0.015 wt% at pH 6.5–8 for hemoglobin. It is noteworthy that both proteins can be precipitated and also foam separated even in strongly alkaline media, such as at pH 12, where the usual flocculents (e.g., aluminum salts) cannot be employed. This work points out the usefulness of infinitely aggregating surfactants as microflotation agents.
  • Masaru Nakahara, Katsumi Maeda, Jiro Osugi
    1980 Volume 53 Issue 9 Pages 2499-2501
    Published: 1980
    Released: April 19, 2006
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    The smectic to cholesteric, cholesteric to isotropic liquid, and solid to isotropic liquid transitions in the following cholesterol esters are determined by an optical method as a function of pressure up to 1 kbar; cholesteryl oleate, cholesteryl linoleate, and cholesteryl linolenate. The pressure dependence of the transition temperatures (dTdP) is in the range of 21 to 36 K kbar−1, and the volume changes (ΔV) computed by means of Clapeyron’s equation are between 0.42 and 1.3 cm3 mol−1 at 1 bar. The volume change for the smectic to cholesteric transition increases with the number of the double bonds in the acids, while that for the cholesteric to isotropic liquid is little affected by the double bonds.
  • Yusei Miyagi, Motohiko Koyanagi, Yoshiya Kanda
    1980 Volume 53 Issue 9 Pages 2502-2505
    Published: 1980
    Released: April 19, 2006
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    The phosphorescence spectra of p-benzoquinone (PBQ) have been studied at 4.2 K in isostructural crystals such as p-dichlorobenzene (DCB), p-bromochlorobenzene (BCB), and p-dibromobenzene (DBB); and in their binary mixed crystals. The variable phosphorescence band patterns observed are interpreted in terms of anisotropic local-field effects of the host environmental molecules. A similarity of the phosphorescence intensity distribution between two systems of PBQ/BCB and PBQ/(0.5 molar fraction of DCB+0.5 molar fraction of DBB) is a manifestation of the existence of effective local-fields in the crystals.
  • Tsunetaka Sasaki, Hisayo Kurosawa, Keiichi Miyasaka, Minoru Mizushima
    1980 Volume 53 Issue 9 Pages 2506-2509
    Published: 1980
    Released: April 19, 2006
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    Flotation of Crystal violet (CV+), neucoccin (NO), CrO42−, PO43−, Fe3+, and Cu2+ ions was studied with use of poly(ethyleneimine) resin (PEI) as an adsorbent, Na-polyacrylate or polyacrylamide as a coagulant and sodium dodecyl sulfate or hexadecyltrimethylammonium chloride as a frother. In line with the results of adsorption studies, NC, PO43−, and CrO42− ions were effectively floated from their dilute solutions but CV+ was not floated so much. The most effective flotation was attained for CrO42− ions, a rapid initial decrease in concentration due to the flotation within 30 s being followed by a gradual decrease and nearly 100% flotation achieved within 10 min for a dilute solution. The rate of flotation follows a bimolecular reaction. The activation energy of flotation, 28.03 kJ mol−1, is equal to that of CrO42− ion adsorption by PEI. Flotation of Fe3+ and Cu2+ ions was effectively carried out through chelate formation of these ions with PEI.
  • Hiroshi Ishikawa, Eiichi Ishii, Itsuki Uehara, Masanori Nakane
    1980 Volume 53 Issue 9 Pages 2510-2513
    Published: 1980
    Released: April 19, 2006
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    In order to eliminate SO2 from HBr gas produced by the reaction between SO2, Br2, and H2O, vapor-liquid equilibrium measurements of the Br2–H2SO4–H2O system saturated with HBr have been made over a wide range of the constituent concentrations. Experiments were carried out in a semi-flow system at 25 °C under atmospheric pressure. The relative concentration of HBr saturated in the liquid phase decreased from 0.31 to 0.05 [mol]/[mol] with an increase in the relative H2SO4 concentration from 0.0 to 0.40 [mol]/[mol]. The solubility of Br2, as defined by Henry’s law constant, varied from 1.1 to ca. 150 atm/mol/mol with the above-mentioned decrease in the HBr concentration. The relation between the partial pressure of SO2 in the gas phase and the composition of the liquid phase was found to be expressed by the following empirical formula: PSO2=K·CHBr·CH2SO4CBr2, where the value of K is 8×10−4 when C is expressed as a relative molar concentration for each species in the liquid phase. The unconverted SO2 can be effectively removed by bringing the effluent gases from the reactor into contact with a HBr-saturated aqueous solution containing an excess of Br2.
  • Kazuhiko Sugasaka, Ayako Fujii
    1980 Volume 53 Issue 9 Pages 2514-2519
    Published: 1980
    Released: April 19, 2006
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    The complex formation of copper(I) with bromide and iodide ions in aqueous 5 M (1 M=1 mol dm−3) Na(ClO4) solutions was studied spectrophotometrically over a pH range from acidic to alkaline. Over the concentration range of 0.05–5 M bromide ions in acidic solutions, the CuBr2 and CuBr32− complexes were found. On the other hand, in the iodide system the CuI2, CuI32− complexes and a higher complex were found under the same experimental conditions, although the composition and the formation constant of the last complex could not be determined in this study. The equilibrium constants for the reactions, CuX2+X=CuX32−, were 13 and 1.6 for the bromide and iodide complexes respectively. A hydrolyzed species of copper(I), Cu(OH)2, was found in an alkaline solution of the two systems. The formation constants, β−22=[Cu(OH)2][X]2⁄[CuX2][OH]2, were evaluated as follows: β−22=(10.0±0.7)×107([Br]<2M),(2.6±0.7)×107([Br]=3M),(1.7±0.7)×107([Br]=4M) in the bromide solutions, (4.0±0.4)×103 ([I]<2 M), (2.5±0.4)×103 ([I]=3 M), (2.2±0.4)×103 ([I]=4 M) in the iodide solutions.
  • Kan Kanamori, Kiyoyasu Kawai
    1980 Volume 53 Issue 9 Pages 2520-2522
    Published: 1980
    Released: April 19, 2006
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    The Raman spectra of bis(ethylenediamine)cobalt(III) complexes have been studied with a view toward differentiating between the cis and trans configurations. It is shown that a correlation can be made between the configurations of the complexes and the intensity of the band due to the chelate-ring-deformation vibration, δ(cycle). Thus, trans isomers exhibit a strong and sharp band near 270 cm−1 due to this mode, while cis isomers exhibit no intense band at this frequency.
  • Satoru Shimba, Shuhei Fujinami, Muraji Shibata
    1980 Volume 53 Issue 9 Pages 2523-2527
    Published: 1980
    Released: April 19, 2006
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    Complexes of the [Co(a)(gly)(tacn)]-type, where tacn represents 1,4,7-triazacyclononane and a is CN, NO2, NH3, NCS, H2O, OH, N3, or Cl, have been prepared and resolved. The CD spectra of these complexes have been measured. On the basis of the X-ray analysis of (−)589[Co(gly)(NH3)(tacn)]I2·H2O, the absolute configurations of the other complexes have been assigned by referring to the CD spectra. These complexes have exhibited a common CD pattern in the T1g-band region, and from this fact a criterion for the assignments of the absolute configurations for the complexes of the fac(D)-[Co(a)(BC)(DDD)]-type has been established.
  • Akio Ichimura, Toyokichi Kitagawa
    1980 Volume 53 Issue 9 Pages 2528-2530
    Published: 1980
    Released: April 19, 2006
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    The voltammetric behavior of the title complexes has been studied. These complexes give a one-electron oxidation wave and a one-electron reduction wave in most solvents. A linear correlation between the (E1⁄2oxE1⁄2red) values and the solubility parameters of the solvents was obtained. The (E1⁄2oxE1⁄2red) values were interpreted in terms of the solvation energy of the complexes.
  • Katsura Mochizuki, Masatoshi Fujimoto
    1980 Volume 53 Issue 9 Pages 2531-2534
    Published: 1980
    Released: April 19, 2006
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    New mixed-ligand complexes [CoIII(pan)(dien)](ClO4)2·EtOH and [CoIII(pan)(trien)](ClO4)·NaClO4 were synthesized. The 1H NMR and the visible absorption spectra of these complexes were compared with those of the free ligand PAN and [CoIII(pan)2]Cl. A remarkable down-field shift observed in the 1H NMR signal for the proton H10 of the cobalt(III) complexes reflects the structural changes in the PAN molecule upon chelatering formation. The reaction between [CoIIICl2(trien)]Cl and PAN gave two kinds of products, which confirmed a strong tendency for the ligand PAN to behave as a planar terdentate ligand.
  • Katsura Mochizuki, Masatoshi Fujimoto, Haruko Ito, Tasuku Ito
    1980 Volume 53 Issue 9 Pages 2535-2539
    Published: 1980
    Released: April 19, 2006
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    Spin-state equilibria between a singlet low-spin and a triplet high-spin species of the title complexes in water were investigated by means of electronic spectra. The equilibrium constants and the thermodynamic parameters, ΔH and ΔS, were evaluated from detailed analysis of the temperature-dependence of the electronic spectra. The electronic spectra of the singlet and the triplet species involved were also derived, from the same analysis. The formation of the triplet species was found to be exothermic, which reflects the predominant contribution of the exothermic change to the formation of nickel(II)–water bond over the contribution of the endothermic change in the bond length caused by the change in spin state. The absolute values of ΔS almost correspond to those expected for the effective liberation of two molecules of water in aqueous solution.
  • Masayoshi Onishi, Hideharu Yamamoto, Katsuma Hiraki
    1980 Volume 53 Issue 9 Pages 2540-2543
    Published: 1980
    Released: April 19, 2006
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    trans-Chloro(3-oxo-1-cyclohexenyl)bis(triphenylphosphine)palladium(II) (1) reacted with 1,2-bis(diphenylphosphino)ethane (dppe), 1,10-phenanthroline (phen), sodium diethyldithiocarbamate–water (1/3), and sodium tetra(1-pyrazolyl)borate {Na[BPZ4]} (Pz=1-pyrazolyl) to give the corresponding new (3-oxo-1-cyclohexenyl)palladium(II) complexes, [Pd(oxch)Cl(dppe)] (oxch=3-oxo-1-cyclohexenyl) (2), [Pd(oxch)Cl(phen)], [Pd(oxch)(S2CNEt2)(PPh3)], and [Pd(oxch)(BPZ4)(PPh3)], respectively. Complex 2 was treated with carbanions derived from methyl and ethyl cyanoacetates and malononitrile, and new diorganopalladium(II) complexes were obtained. These complexes were characterized by means of elemental analyses and IR and 1H-NMR spectroscopy. The stereochemical nonrigidity of the BPZ4 complex was discussed.
  • Ushio Sakaguchi, Michie Nakano, Hayami Yoneda
    1980 Volume 53 Issue 9 Pages 2544-2547
    Published: 1980
    Released: April 19, 2006
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    The rate of deuteration at malonate hydrogens has been measured for [Co(mal)(N)4]+ and [Co(malH)(NH3)5]2+ ions in aqueous solution over the pD range of 2 to 8, where mal=malonate dianion, malH=malonate monoanion, and (N)4=(NH3)4, (ethylenediamine)2, (1,3-propanediamine)2, (1,10-phenanthroline)2, or (2,2′-bipyridine)2. For the tetraamine type complexes with a chelated malonate ligand, the deuteration process is acid-catalysed up to pD=about 4 and base-catalysed at higher pD values. This contrasts with the behavior of the unidentate malonate ligand, for which the deuteration is base-catalysed up to pD=3.5, whereupon the deprotonation of the carboxylate group takes place and the deuteration rate steps down to a constant, pH-independent value. The deuteration mechanisms are discussed.
  • Kunio Ohzeki, Masakuni Saruhashi, Tomihito Kambara
    1980 Volume 53 Issue 9 Pages 2548-2551
    Published: 1980
    Released: April 19, 2006
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    The stability constant of binuclear copper(II) complex with 3,6-Dioxaoctane-1,8-diamine-N,N,N′,N′-tetraacetric acetic acid (ethylene glycol bis[2-[bis(carboxymethyl)amino] ethyl] ether, customarily abbreviated to EGTA of Y) was determined on the basis of potentiometric titration by means of a copper(II) ion-selective electrode. In acetate buffer solution of pH 5.8 titration curves of copper(II) with EGTA show two distinct end points corresponding to Cu2Y and CuY complexes. The formation constant of the binuclear copper(II) complex was determined from the potential response in the titration fraction between first and second end points. The logarithmic value was found to be log KCu2Y=6.40 at ionic strength of 0.2 M (KNO3–acetate buffer solution) at 25±0.5 °C.
  • Katsuhira Yoshida, Masaru Matsuoka, Yoshio Yamashita, Teijiro Kitao
    1980 Volume 53 Issue 9 Pages 2552-2554
    Published: 1980
    Released: April 19, 2006
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    In the presence of some metal ions and atmospheric oxygen, 1-aminoanthraquinone(1) reacts readily with butylamine to give 1-amino-4-butylaminoanthraquinone(2a), along with a small amount of 1,4-diaminoanthraquinone, which is produced by the dealkylation of 2a. The activity of the metal ions decreased in the following order: Co(II)>>Ni(II)>Cu(II)>Al(III). The reaction is remarkably affected by the substitution of an alkyl group into the amino group of 1, the addition of a chelating agent, the counter anion of metal ions, and the reaction temperature. By the use of cobalt(II) chloride, the reaction proceeds most smoothly at about 30 °C. Both anthraquinone and 2-aminoanthraquinone show no sign of the reaction under the same conditions. A possible mechanism involving the formation of a metal complex, followed by the nucleophilic attack of amine at the 4-position and the oxidative abstraction of the hydride anion by atmospheric oxygen is proposed.
  • Toshifumi Miyazawa
    1980 Volume 53 Issue 9 Pages 2555-2565
    Published: 1980
    Released: April 19, 2006
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    N-Carboxymethyl(Cm-)amino acids and their mono- and diesters were prepared by several routes, and their physical and chiroptical properties were compared with those of the parent amino acids and their esters. The isolation procedure was improved for the preparation of the free Cm-amino acids obtained from the corresponding amino acids and bromoacetic acid; the aimed-at compounds were also obtained by the catalytic hydrogenolysis of the dibenzyl esters. The isomeric pairs of monoalkyl esters of Cm-amino acids were similarly accessible via the benzyl alkyl esters. The diesters proved to be suitable for the GLC and MS analyses of Cm-amino acids. All the free Cm-L-amino acids and the dicyclohexylammonium salts of their N-ethylthiocarbonothioyl derivatives show positive Cotton effects at 200–225 nm and at 335–350 nm respectively in CD measurements; therefore, these correlations can be used for the configurational assignments of Cm-amino acids.
  • Tokuji Takeda, Satoshi Yasuhara, Shoji Watanabe
    1980 Volume 53 Issue 9 Pages 2566-2569
    Published: 1980
    Released: April 19, 2006
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    The reactions of substituted epoxides with alkyl chloroacetate in the presence of lithium salts, quarternary salts and zinc chloride were studied. The reaction of 1-chloro-2,3-epoxypropane (1a) with butyl chloroacetate (BCA) in the presence of any of these catalysts yielded exclusively butyl [2-chloro-1-(chloromethyl)ethoxy]acetate (2a) via the normal cleavage of 1a followed by the reaction with the chloroacetate. On the other hand, the reaction of 1,2-epoxypropane(1b) with BCA yielded a mixture of isomeric products resulting from the normal and abnormal cleavages of 1b, and the ratio of the normal and abnormal products is dependent on the type of the catalyst. Moreover, it was found that lithium salt alone catalyzed the insertion reaction in a polar aprotic solvent, whereas the reaction in aromatic solvent needed a suitable co-catalyst such as hexamethylphosphoric triamide and triphenylphosphine oxide.
  • Shigeru Kobayashi, Tsunehiko Fukuda, Hidefumi Yukimasa, Masahiko Fujin ...
    1980 Volume 53 Issue 9 Pages 2570-2577
    Published: 1980
    Released: April 19, 2006
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    N-Acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and thirteen new analogs were synthesized by the conventional organic chemical procedure using dicyclohexylcarbodiimide-N-hydroxy-5-norbornene-2,3-dicarboximide as a coupling agent. Their ability to induce delayed-type hypersensitivity to N-acetyl-3-(4-arsonophenylazo)-L-tyrosine in guinea pigs was assayed. The results indicate that the presence of an α-amino acid adjacent to the lactic acid moiety in MDP is important for the high biological activity, the valine analog having the most favorable effect. The structure-activity relationship is discussed.
  • Yoshiaki Motozato, Yoshiaki Furuya, Toshikazu Matsumoto, Tsukasa Nishi ...
    1980 Volume 53 Issue 9 Pages 2578-2581
    Published: 1980
    Released: April 19, 2006
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    The rate of the decarboxylation of trichloroacetic acid (abbreviated as TCAH) in the presence of β-cyclodextrin(βCD) in an aqueous solution of sodium hydroxide has been followed by the determination of the remaining TCAH. The rate equation was given by
    Rate=(k_1T+k_1TCC_βCD)C_TCAH^1/2+(k_2T-k_2TCC_βCD)C_TCAH.
    A probable bimolecular decarboxylation mechanism which involves the unionized molecule of TCAH rather than the anion was proposed and discussed.
  • Takao Saito, Isao Oikawa, Shinichi Motoki
    1980 Volume 53 Issue 9 Pages 2582-2585
    Published: 1980
    Released: April 19, 2006
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    9-Fluorenethione S-p-toluenesulfonimide reacted with diphenylketene to give two regioisomeric 1,3-dipolar cycloadducts. The thione S-imide and symmetrical dialkylcarbodiimides produced 3-tosylimino-1,2,4-thiadiazolidines. In the reaction with ketenimines, there occurred siteselective cycloaddition reactions on C=N vs. C=C bonds in the imines and further rearrangement of the 1,2,4-thiadiazolidine adducts.
  • Sh\={o}ichi Kikkawa, Masakatsu Nomura, Michimasa Shimizu
    1980 Volume 53 Issue 9 Pages 2586-2591
    Published: 1980
    Released: April 19, 2006
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    The dehydrochlorination of 1,1-dichloropropane and 1,1-dichloro-3-methylbutane was carried out over molten salt catalysts (mainly ZnCl2-containing melts) using a conventional flow system. The cis/trans ratio (1.8) of the resulting olefins from 1,1-dichlorobutane was found to stand between the ratio (1.4) with 1,1-dichloro-3-methylbutane and the ratio (2.2) with 1,1-dichloropropane; this can be explained by considering the stereochemistry of the adsorbed carbonium ions. The detailed results of the reactions of three butene isomers with chlorine through molten salts were presented. The selective formation of butadiene was explained in terms of the thermally assisted attack of chlorine in the allylic positions of butene, followed by the 1,2- or 1,4-elimination of HCl from chlorobutenes, a process which is strongly assisted by the ZnCl2-containing melts. The reaction of 2-methyl-2-butene and cyclohexene with chlorine through molten salts was also undertaken. The addition of Zn powder to ZnCl2 melts in advance was found to improve the selectivity for the formation of isoprene and cyclohexadiene. Because the HCl evolved reacts instantly with Zn powder to afford ZnCl2 and hydrogen, Zn powder substantially prohibits the addition of HCl to dienes yielding chlorobutenes and chlorocyclohexenes.
  • Yoichi Ozawa, Toshiaki Tsuji, Yasuo Ariyoshi
    1980 Volume 53 Issue 9 Pages 2592-2593
    Published: 1980
    Released: April 19, 2006
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    A convenient synthesis of glutathione (GSH) by the use of minimal protecting groups was investigated. N-Formyl-L-2-amino-4-cyanobutyric acid ethyl ester was condensed with ethyl L-cysteinylglycinate to give (4R)-2-[(3S)-3-ethoxycarbonyl-3-(formylamino)propyl]-4-(ethoxycarbonylmethylcarbamoyl)-2-thiazoline. This compound was saponified in aqueous acetone at −15–−20 °C and subsequently treated with dilute H2SO4 (pH 4) to yield formylglutathione, whose formyl group was then hydrolyzed with 0.5 M (1 M=1 mol dm−3) H2SO4 to give free GSH. For purification, this was changed to a copper thiolate, which was then decomposed with H2S to afford pure GSH.
  • Noboru Kitamura, Shigeo Tazuke
    1980 Volume 53 Issue 9 Pages 2594-2597
    Published: 1980
    Released: April 19, 2006
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    Photoinduced ternary electron transfer reactions have been demonstrated in the system of perylene(Pe)-1,4-dicyanobenzene(DCB)-N-vinylcarbazole(VCZ) in acetone. Photoexcited perylene was recycled via two successive electron transfer reactions while VCZ-cyclodimer and/or -polymer were obtained in good yields. Quantum yields for VCZ-cyclodimer and -polymer formation were larger in the electron transfer sensitization system in comparison with the other reaction systems such as in the Pe–VCZ or the VCZ–DCB system. The photocatalytic effect of the electron transfer sensitization was clearly confirmed in the present system, by estimating the overall sensitizer efficiency as over 8000 although chain propagation steps of VCZ cation radical are involved in the present reaction processes.
  • Noboru Kitamura, Shigeo Tazuke
    1980 Volume 53 Issue 9 Pages 2598-2604
    Published: 1980
    Released: April 19, 2006
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    The action of electron transfer sensitization was quantitatively discussed by measuring photooxidative dye formation of leuco Crystal Violet (LCV) in the perylene (Pe)-1,4-dicyanobenzene(DCB)–LCV combination in polar media. Under the conditions of exclusive photoexcitation of perylene (λex at 435 nm), the kinetic study revealed that the turn over number of perylene as a sensitizer was immeasurably large in the ternary system in vacuo. This is an indication that perylene is indeed recycled via two successive electron transfer processes. The turn over number decreased to 58 in air, probably due to instability of intermediate ion radicals. The quantum yield was larger for the ternary system than for the binary system(Pe–LCV) irradiated at 435 nm. Although the absolute quantum yield of photooxidation was in the order of 10−3 or less in both systems, the ternary electron transfer system was apparently advantageous since the efficiency of back electron transfer would be reduced when multiple electron transfer processes are linked. Furthermore, the concept of electron transfer sensitization enables spectral sensitization and utilization of low energy photons in singlet state photoredox reactions. Such systems would be considered as a model for the primary action of photosynthesis.
  • Koichi Mizusaki, Hidefumi Yamamoto, Satoru Makisumi
    1980 Volume 53 Issue 9 Pages 2605-2609
    Published: 1980
    Released: April 19, 2006
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    γ-Hydroxy-DL-ornithine was obtained from an alkaline hydrolysate of 2,5-diamino-4-pentanolide synthesized according to the method of Talbot et al. The amino acid preparation was found to be a racemic mixture composed of 34% erythro and 66% threo isomers by a new chromatographic assay. This assay is based on the conversion of the basic amino acid to a neutral amino acid by acetylation of the δ-amino group and the analysis of the resulting Nδ-acetyl derivative with an automatic amino acid analyzer by the ordinary method. Two diastereoisomers of γ-hydroxy-DL-ornithine were separated by column chromatography on Dowex 50 and isolated as their crystalline hydrochlorides. Guanidination of the separated racemic diastereoisomers gave the corresponding diastereoisomeric γ-hydroxyarginines, hydrolysis of which with arginase yielded erythro- and threo-γ-hydroxy-DL-ornithines.
  • Shigeru Ozasa, Noriko Hatada, Yasuhiro Fujioka, Eiichi Ibuki
    1980 Volume 53 Issue 9 Pages 2610-2617
    Published: 1980
    Released: April 19, 2006
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    Twelve linear polyphenyls, including quinque- to octiphenyl, were synthesized by the Ullmann cross-coupling reaction of iodobiphenyl with diiodobenzene or iodoterphenyl. Ultraviolet spectral studies of the polyphenyls indicated that the positions of the K-bands above ca. 260 nm, regardless of the presence of o- or m-phenylene unit(s), may be considered to be an indication of the approximate number of consecutive p-phenylene units. Infrared studies also showed that the locations of strong or medium bands in the 815–850 cm−1 region may give the same information. The HMO calculations of the longest wavelength absorption bands of twenty-four polyphenyls were carried out. A comparison between the calculated and observed wavelengths gave rather good agreement, except in the cases of two compounds. The signals of the proton magnetic resonance spectra of eighteen polyphenyls were assigned tentatively. The correlations between the arrangement of the benzene rings and the spectral patterns are discussed.
  • Takeo Katsushima, Masato Yoshikawa, Ryohei Yamagughi, Mituyosi Kawanis ...
    1980 Volume 53 Issue 9 Pages 2618-2620
    Published: 1980
    Released: April 19, 2006
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    A reaction of 2,4-dehydrohomoadamantane with NBS in AcOH followed by LiAlH4 reduction and subsequent CrO3–pyridine complex oxidation gave endo-2-bromohomoadamantan-4-one (9) in good yield. A treatment of 9 with t-BuOK in t-BuOH followed by Wolff-Kishner reduction furnished 2,5-dehydrohomoadamantane.
  • Hiroshi Suginome, Norio Maeda
    1980 Volume 53 Issue 9 Pages 2621-2625
    Published: 1980
    Released: April 19, 2006
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    Hypoiodites of 3α- and 3β-methyl-5-cholesten-3-ols in benzene containing mercury(II) oxide and iodine gave 3α,5-epoxy-6β-iodo-3β-methyl-A-homo-4-oxa-5α-cholestane in 50–66% yield on irradiation or heating in the dark. Some minor products including the 6α-epimer were also found. The corresponding reaction with silver oxide and iodine reagent gave the same epoxide in 52% yield, together with a low yield of 3,4-seco-3-methyl-3-oxo-5-cholesten-4-al. Hydrogenolysis of the 6β-iodide with Pd–C as a catalyst gave 3α,5-epoxy-3β-methyl-A-homo-4-oxa-5α-cholestane (52% yield), together with the 6α-epimer arising from isomerization. The former, on treatment with boron trifluoride etherate and acetic anhydride in benzene, was transformed into 2-acetyl-3-methyl-5-acetoxymethyl-4-oxa-5β-cholestan-2-one. This was converted into 2β-acetyl-3α,5-epoxy-3β-methyl-4-oxa-A-homo-5α-cholestane by the treatment with aqueous methanolic potassium hydroxide.
  • Hiroshi Suginome, Norio Maeda
    1980 Volume 53 Issue 9 Pages 2626-2629
    Published: 1980
    Released: April 19, 2006
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    Irraidation of a benzene solution of hypoiodite of 4,4-dimethyl-5-cholesten-3β-ol (1) in the presence of mercury(II) oxide and iodine gave a mixture of products, from which 3α,5-epoxy-6β-iodo-A-homo-4-oxa-5α-cholestane (2%), 4,4-dimethyl-3-oxa-5-cholestene (3) (10%), and 4a,4a-dimethyl-3α,5-epoxy-A-homo-4-oxa-5α-cholest-6-ene (4) (4%) were isolated. The thermally-induced reaction on 1 conducted at 55–60 °C gave 3 and 4 in lower yields. The reaction with the use of lead tetraacetate-iodine reagent also gave a complex mixture, from which only 4 was obtained in 22% yield. The formation of 4,4-dimethyl-3-oxa-5-cholestene skeleton is parallel with the case of the photo- and thermally-induced reactions of hypoiodite of 3α,4,4-trimethyl-5-cholesten-3β-ol and appears to be particular with 5-cholesten-3β-ol bearing dimethyl groups at the C-4 under similar conditions. The formation is explained in terms of radical-induced decarbonylation of initially formed 4,4-dimethyl-2-formyl-3-oxa-5-cholestene.
  • Mutsumi Hamado, Kazu Kurosawa
    1980 Volume 53 Issue 9 Pages 2630-2633
    Published: 1980
    Released: April 19, 2006
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    The reaction of 3-hydroxyflavones (1ad) with lead(IV) acetate gave 1,2-diphenylethanediones (2ad), 1,2-diphenyl-2-hydroxyethanones, 2-hydroxybenzoic acids (7 and 9), and benzoic acids (8 and 10), and the reaction with manganese(III) acetate yielded 2, 7, 8, 9, and 10. In addition to 2, 7, and 10, 6-methoxy-2-(4-methoxybenzoyloxy)-3(2H)-benzofuranone and 2-hydroxy-4-methoxybenzaldehyde were obtained in the reaction of 1c with manganese(III) acetate. It has been established by the studies of 14C-labelled compounds that the C(3) in the 3-hydroxyflavone was lost during the reaction.
  • Isao Kuwajima, Akio Mori, Masahiro Kato
    1980 Volume 53 Issue 9 Pages 2634-2638
    Published: 1980
    Released: April 19, 2006
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    Reductive cleavage of carbon–sulfur linkages of silyl enol ethers of thiocarboxylic S-esters can be induced by treatment with sodium or potassium–sodium alloy in the presence of chlorotrimethylsilane, and the corresponding silyl enol ethers of acyltrimethylsilanes can be prepared in high yields.
  • Ken-ichi Sato, Kenji Koga, Hironobu Hashimoto, Juji Yoshimura
    1980 Volume 53 Issue 9 Pages 2639-2641
    Published: 1980
    Released: April 19, 2006
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    A study was made on the kinetics of the epimerization of 1,2: 5,6-di-O-isopropylidene-3-C-nitromethyl-α-D-allofuranose in nitromethane to its 3-epimer in the presence of a small amount of sodium methoxide. The activation energy was found to be 75±8 kJ/mol, the intermediate in epimerization being 1,2: 5,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose with use of the labelled compound.
  • Sigeru Torii, Tsutomu Inokuchi
    1980 Volume 53 Issue 9 Pages 2642-2646
    Published: 1980
    Released: April 19, 2006
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    The efficient synthetic procedures to dl-β-costol (1a), dl-arctiol (2), and the related eudesmane type sesquiterpenes are described. trans-8,8-Ethylenedioxy-4aβ-methyldecalin-2α-ol (6a), prepared from trans-1,1-ethylenedioxy-4aβ-methyl-Δ6,7-octalin by epoxidation and subsequent reduction of the epoxy ring, was converted into 1a as follows: (1) deacetalization of 6a followed with mesylation, giving 2α-methylsulfonyloxy-4aβ-methyldecalin-8-one (7b), (2) condensation of 7b with methyl sodiomalonate and subsequent Wittig reaction with methylenetriphenylphosphorane affording dimethyl (trans-4aβ-methyl-1-methylene-7β-decalinyl)malonate (9), (3) reduction of sodium salt of 9 with NaAl(OCH2CH2OMe)2H2. Oxidation of 1a with PCC gave dl-β-costsd. dl-Arctiol (2), structurally related to 1a, was prepared from trans-5,5-ethylenedioxy-8aβ-methyldecalin-2-one. Introduction of two equatorial substituents, such as hydroxyl and 1-hydroxy-1-methylethyl groups at the C-2 and C-3 carbons of 2, was carried out as follows: (1) methoxycarbonylation followed by methylation of the sodium salt of keto ester with MeLi, (2) subsequent reduction with lithium in liquid NH3, giving trans-5,5-ethylenedioxy-3β-(1-hydroxy-1-methylethyl)-8aβ-methyldecalin-2α-ol (14), and (3) deacetalization of 14 followed by the reaction with methylenetriphenylphosphorane. dl-Eudesma-4(14),7(11)-dien-8-one was also prepared from 2 by oxidation with PCC followed by dehydration and subsequent isomerization of double bond.
  • Mamoru Ai, Tian-hsi Tsai, Atsumu Ozaki
    1980 Volume 53 Issue 9 Pages 2647-2650
    Published: 1980
    Released: April 19, 2006
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    The synthesis of furan by direct vapor-phase oxidation of crotonaldehyde has been studied. It was found that heteropoly compounds such as 12-molybdophosphoric acid are more effective than the mixed oxide (MoO3–P2O5, P/Mo=1/12) as catalyst for furan formation, and that the cesium salt of 12-molybdophosphoric acid with a Cs/Mo atomic ratio of 1/12 is more effective than the 12-molybdophosphoric acid catalyst. The rate of furan formation increases with increase in steam concentration in the feed, but is nearly independent of oxygen and crotonaldehyde concentrations. The yield of furan increases by decreasing the crotonaldehyde concentration, attaining 60 mol% at a concentration of 0.17 vol% in the feed. The conversion of crotonaldehyde at maximum yield is 90–95%.
  • Atsuyoshi Ohno, Shinro Yasui, Shinzaburo Oka
    1980 Volume 53 Issue 9 Pages 2651-2654
    Published: 1980
    Released: April 19, 2006
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    Reductions of 1-acetylisoquinoline (AQ), 1-benzoylisoquinoline (BQ), and isoquinoline-1-carbaldehyde have been studied kinetically and the results are compared with those of 2-acetylpyridine (AP), 2-benzoylpyridine (BP), and pyridine-2-carbaldehyde. Equilibrium constants for complexes between these substrates and zinc ion have also been studied. Kinetic deuterium isotope effects for AQ and BQ are smaller than the corresponding product isotope effects, respectively, whereas those for AP and BP are identical. The results are discussed in terms of stability and reactivity of intermediate radical-ion pair, and it is concluded that strong coordination of a metal ion onto the reaction site of a substrate facilitates the complexation but interferes the reduction.
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