Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 53 , Issue 7
Showing 1-50 articles out of 68 articles from the selected issue
  • Norio Ohtomo, Kiyoshi Arakawa
    1980 Volume 53 Issue 7 Pages 1789-1794
    Published: 1980
    Released: April 19, 2006
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    The structure factors Sm(Q) for aqueous solutions of NaCl and KCl at room temperature have been determined by means of the LINAC-TOF-neutron diffraction method. A revised subtraction method was applied to diffraction data of the solutions. Results obtained for the structure of the nearest hydration shell around ions are as follows, (a) The coordination numbers are 8 for Na+ and 6 for Cl in the NaCl solution and 8 for K+ and 6 for Cl in the KCl solution; (b) the average ion-oxygen distances are 2.50±0.10 Å for Na+, 2.70±0.10 Å for K+, and 3.10±0.05 Å for Cl; (c) around chloride ions water molecules take the configuration to orient the vector which bisects the D–O–D angle on a straight line joining an oxygen atom and the anion. Analysis was performed on the data of LiCl and CsCl solutions.
  • Kazumitsu Kojima, Kiyoshi Arakawa
    1980 Volume 53 Issue 7 Pages 1795-1800
    Published: 1980
    Released: April 19, 2006
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    The reference interaction site model (RISM) theory was applied to diatomic molecular fluids, by using three different forms of approximation for site-site direct correlation function. Applicability of the three forms of RISM equation, RISM-1, RISM-2, and RISM-3, was examined, site-site pair correlation functions being calculated from them and a comparison of the results with those of computer simulations being made. Structure factor for liquid nitrogen, oxygen, and bromine were obtained from the solution of the RISM-2 equation and compared with experimental results.
  • Hiroshi Sekiya, Yasuhiko Gondo, Yoshiya Kanda
    1980 Volume 53 Issue 7 Pages 1801-1806
    Published: 1980
    Released: April 19, 2006
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    Electron spin resonance absorption has been observed in a single-crystal solid solution of benzo[f]quinoline in biphenyl under irradiation at 120 K with light from a high-pressure mercury lamp. The fine structure of the resonance spectrum observed at 9.25 GHz can be described by the spin Hamiltonian
    HH·g·S+D[S_z^2-\frac13S(S+1)]+E(S_x^2-S_y^2)
    in which S=1, D=±0.09926(18) cm−1, E=\mp0.04781(6) cm−1, gxx=2.0024(6), gyy=2.0018(4), and gzz=2.0018(4); the z axis is normal to the molecular plane, the x and y axes being the in-plane fine-structure principal axes. The principal x axis deviates by ±4° from the biphenyl long axis and the principal z axis by 7° from the biphenyl out-of-plane axis. The phosphorescence spectra and lifetimes have been measured both at 77 K and at 4.2 K. Marked doublet splittings were observed in the phosphorescence bands at 4.2 K, suggesting a large guest-host interaction.
  • Osamu Takahashi, Takashi Yamauchi, Toshihiko Sakuhara, Hideshi Hattori ...
    1980 Volume 53 Issue 7 Pages 1807-1812
    Published: 1980
    Released: April 19, 2006
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    The reaction of pentane to 2-methylbutane was carried out at 0 °C over solid super acid catalysts which were prepared by treatment of various metal oxides with SbF5 under different conditions, and the preparation conditions that affect the catalytic behavior of the catalyst were examined. Among the different base metal oxides, TiO2–ZrO2 became the most active catalyst when treated with SbF5. The maximum conversion to 2-methylbutane which appeared in the reaction of pentane was high when a base metal oxide was treated with SbF5 at a low temperature, and also when the reaction temperature was low. At the maximum conversion, the selectivity of the catalysts for the skeletal isomerization was almost 100%. As the reaction of pentane proceeded, the catalytic activity for the skeletal isomerization to 2-methylbutane was decreased but that for the formation of 2-methylpropane from 2-methylbutane was increased. The reaction mechanism is briefly discussed.
  • Tetsuo Miyazaki, Selma Matheus Loureiro Guedes, Kenji Fueki
    1980 Volume 53 Issue 7 Pages 1813-1816
    Published: 1980
    Released: April 19, 2006
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    Selective hydrogen-atom-abstraction reaction by an H or D atom has been studied in a neo-C5H12–C2H6 (less than 1 mol%) mixture at 77 K by ESR spectroscopy. The H (or D) atom produced by the photolysis of HI (or DI) reacts with neo-C5H12 and C2H6 to form neo-C5H11 and C2H5 radicals. In order to obtain H atoms with different kinetic energies, the photolysis was performed with different lights of 313, 254, and 229 nm. The selective formation of the C2H5 radical by the reaction of the H (or D) atom with C2H6 becomes more effective with the decrease in the energy of the H (or D) atom. The formation of the neo-C5H11 radical by the reaction of the H (or D) atom with neo-C5H12 becomes more effective with the increase in the energy of the H (or D) atom.
  • Kazunori Matsuki, Yukio Nagahira, Hideo Fukutome
    1980 Volume 53 Issue 7 Pages 1817-1824
    Published: 1980
    Released: April 19, 2006
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    The UV absorption spectra at normal incidence and the polarized spectra at 45° incidence of monolayers of vitamin K1, α-tocopherylquinone, vitamin E, ergosterol, and vitamin D2 were measured. The absorption peaks of the monolayers of vitamin K1, α-tocopherylquinone, and vitamin D2 shifted to wavelengths longer than those in a hexane solution, while vitamin E and ergosterol showed little shift. The orientations of their chromophores in the monolayers were investigated by means of the dichroic ratios obtained from their polarized spectra. The molecular axes of vitamin K1, α-tocopherylquinone, and vitamin E were found to be oriented in the range from 0° to about 30° against the normals of their monolayer planes. The molecular axis of ergosterol was found to tilt about 24° against the normal of the monolayer plane. For vitamin D2, no reliable conclusion could be obtained as to its orientation.
  • Hiroyasu Nomura, Yoshiaki Tsukamoto, Ronald Ernest Verrall, Yutaka Miy ...
    1980 Volume 53 Issue 7 Pages 1825-1831
    Published: 1980
    Released: April 19, 2006
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    The Raman and infrared spectra of 1,4-bis(triethylammonio)butane dibromide (J4), 1,10-bis(triethylammonio)decane dibromide (J10), and tetraethylammonium bromide (TEABr) were measured in the solid and dissolved states. The Raman spectra of these salts in the solid and solution states were roughly similar to those of normal paraffins having the same number of skeletal atoms, but some minor differences were found. It was confirmed that molecular conformations of these ions in the solid and solution states are somewhat similar and take the all-trans form, but in main chain of J4 and J10, the gauche form is also observed. In addition, the effects of hydrophobic interaction of these salts in aqueous solution are discussed by comparison of the Raman spectra of OH stretching vibration region of water.
  • Sumio Ozeki, Shoichi Ikeda
    1980 Volume 53 Issue 7 Pages 1832-1836
    Published: 1980
    Released: April 19, 2006
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    Surface tension of aqueous NaCl solutions of dodecyldimethylammonium chloride has been measured at high NaCl concentrations. Surface excesses of surfactant cation, Na+ and Cl are derived by means of the Gibbs adsorption isotherm from the derivatives of surface tension with respect to surfactant concentration and NaCl concentration. The rational mean activity coefficients of surfactant and NaCl are both approximated by a common expression satisfying the Brönsted principle for mixed electrolytes but including the ionic strength as a variable. Saturated value of surface excess of surfactant cation remains constant at low NaCl concentrations up to 0.10 M, while it increases as the NaCl concentration exceeds 0.50 M. The adsorption of Na+ is negative at low NaCl concentrations, but it increases rapidly and is positive above 0.50 M NaCl. Surfactant and NaCl are subject to the strong salting-out effect when the NaCl concentration is higher than 0.50 M. The Corrin-Harkins plot of the critical micelle concentration at high NaCl concentrations deviates from the straight line.
  • Shoichi Ikeda, Sumio Ozeki
    1980 Volume 53 Issue 7 Pages 1837-1841
    Published: 1980
    Released: April 19, 2006
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    The Gibbs adsorption isotherm for quaternary systems of water, weak base, HCl or NaOH, and NaCl including a vapor-solution interface is expressed in terms of variations of chemical potentials of neutral components added to make up the solution. Four systems are treated, and the Gibbs convention is introduced in such a way that the surface excess of added water is zero and the surface excesses of solute components are defined. Assuming that the activity coefficients of solute components are unity, the lowering of surface tension is given in terms of variations of total molar concentrations of weak base or its hydrochloride, HCl or NaOH, and NaCl, or of pH of the solution.
  • Kaname Kasama, Yasunobu Inoue, Iwao Yasumori
    1980 Volume 53 Issue 7 Pages 1842-1847
    Published: 1980
    Released: April 19, 2006
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    The mechanism of ethylene hydrogenation on a thermally activated CaO was studied in the overall temperature range of 197–623 K. The maximum in the reaction rate was observed around 320 K, while the activation energy was found to vary with the range of reaction temperatures, i.e., 12.6 kJ/mol (197–273 K) and −16.7 kJ/mol (373–623 K). The partial pressure dependence of the rate was also different in these ranges; the reaction orders with respect to the hydrogen and ethylene pressures were 0.7 and nearly zero at 273 K respectively, whereas the orders shifted to 1.0 and 0.9 at 523 K in the pressure range from 6 to 40 Torr (1 Torr=133.3 Pa). The reaction with deuterium at 523 K produced ethane containing widely distributed deuterium and was accompanied by the formation of highly-exchanged ethylene, HD, and H2 molecules in the gas phase. On the contrary, the reaction at 273 K formed ethane [D2] (>60%) selectively, and the hydrogen-deuterium exchange occurred to a lesser extent in both ethylene and deuterium. By the proposed associative mechanism, the variation in the kinetic behavior with the temperature was explained in terms of the change in the slow step from the reaction between the adsorbed hydrogen and surface ethylene to the hydrogenation of the ethyl radical. The poisoning of the hydrogenation by preadsorbed CO indicated that only 0.5% of the total surface atoms contributed actively to the reaction. On the basis of these results, the structures of active sites are briefly discussed.
  • Hitoshi Watarai, Nobuo Suzuki
    1980 Volume 53 Issue 7 Pages 1848-1852
    Published: 1980
    Released: April 19, 2006
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    The partition equilibria of 7 normal aliphatic (C5-C9) β-diketones were investigated in the two-phase systems of heptane/water–dimethyl sulfoxide (DMSO) mixed solvents at 25 °C. The partition coefficients, P, of the keto and enol forms of the β-diketones were determined, and the linear correlations between logP and the number of carbon atoms in the n-alkyl groups were observed. In general, an increase in the mole fraction of DMSO, Xs, in the mixed-solvent phase caused a lowering of the partition coefficient, while with smaller β-diketones, distinct maxima were observed at Xs\simeq0.2. The solvent effect of the mixed-solvent phase was interpreted on the basis of the extended McDevit-Long theory previously proposed by the present authors.
  • Fumio Shimoda
    1980 Volume 53 Issue 7 Pages 1853-1859
    Published: 1980
    Released: April 19, 2006
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    The ESR and ENDOR spectra were observed for the 2,6-di-t-butyl-4-cyclopropylphenoxyl radical. The assignments of the proton hyperfine coupling constants were confirmed with reference to those of the 2,6-di-t-butyl-4-methyl- and 4-(1-deuteriocyclopropyl)phenoxyl radicals. The β-proton hyperfine coupling constant for the cyclopropyl group and its temperature dependence were precisely determined. Of particular interest is the fact that the observed cyclopropyl β-proton splitting is smaller than the γ-proton splittings (A4β:0.72, A4γ1:0.83, A4γ2: 1.44 G at −70 °C). Based on the modified cos2θ rule, A4β=(1.85⟨cos2θ⟩−0.10)×A4Me, where the conjugative interaction between the π-system and the cyclopropyl pseudo π-orbital was incorporated, as proposed by Hudson and Bauld, the β-proton splitting was evaluated. The magnitude of the β-proton splitting and its temperature dependence were interpreted in terms of the restricted rotation of the cyclopropyl group in a two-fold potential; the stable conformation was the bisected one. The rotational barrier height, which corresponds to the difference in energy between the bisected and perpendicular conformations, was estimated to be 2.6 kcal/mol. The rotational barrier was attributed to the stabilization of the bisected conformation arising from the conjugative interaction of the aromatic and cyclopropyl moieties.
  • Yoichi Sakuma, Masao Aida, Makoto Okamoto, Hidetake Kakihana
    1980 Volume 53 Issue 7 Pages 1860-1863
    Published: 1980
    Released: April 19, 2006
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    Isotopic plateau displacement chromatography, a useful method for isotope separation is presented. The boric acid band formed in a column of weakly basic anion exchange resin Diaion WA21 can be eluted with pure water. In order to obtain good accumulation of the isotope effect, a series of experiments with different migration length were carried out. The boron-10 enriched part of the boric acid absorbed band was always preceded by the isotopic plateau part, in which the atomic fraction of boron-10 was maintained at its original value. The atomic fraction of boron-10 at the end of the chromatogram increased with migration length, and in the case of 256-m migration, boron-10 was enriched from its original atomic fraction of 19.84 to 91.00%, the separation factor S being constant irrespective of migration length: S=1.0100±0.0005.
  • Tsunetaka Sasaki, Kaoru Kushima, Kazunori Matsuda, Hitoshi Suzuki
    1980 Volume 53 Issue 7 Pages 1864-1866
    Published: 1980
    Released: April 19, 2006
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    The interaction between poly(ethylene oxide) (PEO), with a molecular weight of 6000, and sodium dodecyl sulfate (SDS) was studied by the gel-filtration method. The elution curve of the PEO–SDS system showed a tail of the elution volume smaller than that of SDS micelles at a concentration larger than about 4 mmol dm−3. This suggests that the PEO–SDS (PS) complex is formed in the system. The dissolution-state diagram in the presence of PEO was then constructed in which the fractions of SDS single ions, SDS micelles, and the PS complex were shown against the SDS concentration. For a constant concentration of PEO, the molecular weight of the PS complex increased with the increase in the concentration of SDS up to the CMC of the PEO–SDS system, beyond which it became constant. The molecular weight of the PS complex was estimated to decrease from 21000 at 0.025 wt% PEO to 15000 at 0.2 wt% PEO.
  • Tsunetaka Sasaki, Osamu Asakawa, Kazuyo Kurosawa, Minoru Mizushima, Te ...
    1980 Volume 53 Issue 7 Pages 1867-1870
    Published: 1980
    Released: April 19, 2006
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    Ion exchange and chelate properties of poly(ethyleneimine) resin (PEI) were studied. Adsorption of neucoccin anions (NC) (maximum 1.7×10−4 mol/g) was greater than that of Crystal Violet cations (CV+) (maximum 0.17×10−4 mol/g), indicating that PEI is an anion exchanger. CV+ adsorption increased with the addition of sodium polyacrylate due to its bridging action between CV+ ions and PEI. Adsorption of CrO42− was confirmed to be much greater than that of NC ions amounting to 4×10−3 mol/g at a sufficiently concentrated solution of CrO42−. The acid exchange capacity of PEI was found to be about the same as the maximum amount of adsorption of CrO42−. Kinetics of adsorption of CrO42− by PEI was studied at various temperatures. Adsorption followed a bimolecular reaction. Activation energy of 28.03×103 J/mol obtained is a right order of magnitude as an ion exchange adsorption. Chelating adsorption of Fe3+ and Cu2+ ions by PEI studied, the maximum amounts of adsorption being 3.1×10−3 mol/g and 3.3×10−3 mol/g, respectively. The values are greater than those for other synthetic polyethylene polyamine. PEI can be used as an anion and metallic cation adsorbent.
  • Isao Ikemoto, Masamichi Yamada, Tadashi Sugano, Haruo Kuroda
    1980 Volume 53 Issue 7 Pages 1871-1876
    Published: 1980
    Released: April 19, 2006
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    Tetrathiafulvalene–tetracyanoquinodimethane (TTF·TCNQ) and related high conductive organic complexes were studied by X-ray photoelectron spectroscopy (XPS). The N 1s peak shape of TTF·TCNQ evaporated film was found to change by X-ray irradiation; the high-binding energy shoulder of the N 1s peak increased its intensity with X-ray irradiation time and finally showed a new peak separated by about 1.5 eV from the main peak. TTF·TCNQ was found to be 1:1 both in the surface and in the bulk. The amounts of charge transfer in TTF·TCNQ and other TTF complexes as well as those in 5,6:11,12-bis(dithio)naphthacene(tetrathiotetracene, TTT) complexes were determined from the analysis of the S 2p peak shape. The amount of charge transfer is 0.56±0.05 in TTF·TCNQ and 0.55±0.05 in TTF·TNAP (tetracyanonaphthoquinodimethane). The molecular ratio of (donor)+ in donor molecules is 0.71±0.05 in TTF·Br0.7, 0.52±0.05 in TTF·I0.7, 0.65±0.05 in (TTF)3(BF4)2, 0.49±0.05 in (TTT)2I3, and 0.93±0.05 in (TTT)(TCNQ)2, which correspond respectively to 100, 73, 100, 100, and 100% charge transfer between donors and acceptors. The N 1s peak shape of TTF·TCNQ is also discussed.
  • Akio Yoshimura, Shunji Kato
    1980 Volume 53 Issue 7 Pages 1877-1880
    Published: 1980
    Released: April 19, 2006
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    The light-driven electron transfer reaction for the system of chlorophyll a–lumiflavin in micelles was studied by means of flash photolysis. In the sodium dodecyl sulfate micellar solution, the chlorophyll a cation radical appeared on the flash excitation and then decayed by means of a second-order process under aerated conditions as well as under deaerated conditions (the radical was not observed in dioxane). The decay parameter in the aerated solution was smaller than that in the deaerated solution by a factor of twenty. The difference in the decay parameter was explained in terms of the function of the surface charge of micelles. In the deaerated solution, the chlorophyll a cation radical decays by means of a reaction with lumiflavin semiquinone of no charge; in the aerated solution, however, it decays by means of a reaction with the O2\ ewdot produced by the electron transfer from lumiflavin semiquinone to oxygen. The latter decay reaction is retarded by the charge on the micelles.
  • Hidemi Todoriki, Yoshifumi Nishimura, Shigesada Higuchi, Akiko Y. Hira ...
    1980 Volume 53 Issue 7 Pages 1881-1887
    Published: 1980
    Released: April 19, 2006
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    Infrared absorption spectra, ultraviolet absorption spectra, phosphorescence spectra, phosphorescence lifetimes, and phosphorescence excitation spectra have been examined of 1-propyl-2-thiouracil in various solvents, including CCl4, CH3OH, CCl4+CH3OH, and CCl4+9-ethyladenine. For 1-cyclohexyluracil, and for 2-S-propyl-2-thiouracil, similar infrared spectroscopic examinations were also made. The results obtained are as follows: (1) In CCl4, the 2-thiouracil residue forms a hydrogen-bond complex with the adenine residue, in which the C4=O is involved in the hydrogen-bond. (2) The binding of 2-thiouracil and adenine is much stronger than that of 2-thiouracil and CH3OH; the 2-thiouracil·methanol binding is stronger than the uracil·methanol binding. (3) The hydrogen-bonding of the 2-thiouracil residue (with CH3OH or with adenine) causes an elevation of the lowest singlet excited state S1, which is probably an 1(nπ*), from 2.5×104 cm−1 to 2.6×104 cm−1, and the lowest triplet excited state T15 which is probably an 1(nπ*), from 2.5×104 cm−1 to 2.6×104 cm−1. (4) The hydrogen bonding of the 2-thiouracil residue causes a great enhancement of the phosphorescence intensity. On the basis of these observations, a discussion is given on the nature of the inter-base hydrogen-bonds involving 2-thiouracil residue.
  • A. K. Lyashchenko, V. S. Goncharov, Toshiro Iijima, Hisashi Uedaira, J ...
    1980 Volume 53 Issue 7 Pages 1888-1891
    Published: 1980
    Released: April 19, 2006
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    Sound velocity and density measurements for H2O and D2O solutions of hexamethylphosphoric triamide (HMPT), [(CH3)2N]3PO at 25 °C have been carried out. The concentration dependence of the molar volumes and adiabatic compressibilities calculated therefrom are interpreted in terms of the water structure. The differences found between the H2O and D2O solutions are similarly explained.
  • Seiichi Sumi, Tadashi Watanabe, Akira Fujishima, Kenichi Honda
    1980 Volume 53 Issue 7 Pages 1892-1897
    Published: 1980
    Released: April 19, 2006
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    With use of AgCl sheet crystal as a window, sensitized photocurrent was measured in an electrochemical cell with a lock-in amplifier. With five sensitizing dyes having different lowest vacant levels, it was found that the higher the level of the dye, the larger the sensitized photocurrent, the sensitized photocurrent increasing with decreasing pAg of the dye-bearing solution. The Ag+ ion effect can be explained by a band edge shift of the AgCl electrode, which also explains the blue desensitization recovery by Ag+ ions.
  • Seiji Sawamura, Yoshihiro Taniguchi, Keizo Suzuki
    1980 Volume 53 Issue 7 Pages 1898-1901
    Published: 1980
    Released: April 19, 2006
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    Absorption spectra of intramolecular CT bands of nitrobenzene, p-nitrophenol, p-nitroaniline, acetophenone, p-hydroxyacetophenone, and p-aminoacetophenone are observed in several nonpolar solvents at 1 bar, and in heptane up to 4400 bar. The fact that all solvent shifts are linearly red for the function of refractive index (n) of solvents, (n2−1)/(2n2+1), consists with the solvent shift theory. On the other hand, the pressure shifts are not straight but convex upward for (n2−1)/(2n2+1) and the red shifts by pressure exceeds the solvent shifts. The similar convex pressure shifts are found in 1Lb bands of several aromatic compounds by plotting the high pressure data of Robertson et al. in spite of the straight solvent shifts in these 1Lb bands measured by us. Therefore the convex pressure shift may be regarded as a general tendency of the electronic spectrum, being ascribed to decrease in the distance between a solute and the surrounding solvents by compression. From comparison with the pressure shift of the intramolecular CT band, it is suggested that, in the pressure shift of the intermolecular CT band of the I2 complexes shifted to red previously, the effect of decrease in the bond distance between a donor and an acceptor proposed by Offen and Nakashima contributes to not a red shift but a blue shift.
  • Ryoka Matsushima, Yoshinori Ichikawa, Katsuyuki Kuwabara
    1980 Volume 53 Issue 7 Pages 1902-1907
    Published: 1980
    Released: April 19, 2006
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    Ultraviolet irradiation of aqueous lactic, glycolic, or 2-hydroxybutanoic acid in the presence of copper(II) leads to photoredox reaction to give corresponding α-keto acid, aldehyde with evolution of carbon dioxide, and the precipitate of copper(I). The mole ratio of the carbonyl products to the consumption of copper(II) is close to 0.5. Oxidative decarboxylation dominates at pH>1 while the formation of α-keto acids favors at lower pH. The formation of α-keto acids is selectively suppressed by the addition of free radical scavengers. Free radical oxidations of the acids with bromine atom or benzoyl radicals give exclusively α-keto acids. The reaction mechanism has been discussed.
  • Kinya Iijima, Shuzo Shibata
    1980 Volume 53 Issue 7 Pages 1908-1913
    Published: 1980
    Released: April 19, 2006
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    The molecular structures of trimethylamine-boron trichloride (CH3)3N·BCl3 and trimethylamine-boron tribromide (CH3)3N·BBr3 were determined from gas electron diffraction and vibrational-spectroscopic data. The molecular parameters and their uncertainties for (CH3)3N·BCl3 were rg(B–Cl)=1.836±0.002 Å, rg(N–B)=1.652±0.009 Å, rg(C–N)=1.497±0.003 Å, rg(C–H)=1.107±0.005 Å, ∠ClBCl=110.9±0.2°, ∠CNC=108.1±0.3°, while those for (CH3)3N·BBr3 were rg(B–Br)=2.001±0.003 Å, rg(N–B)=1.663±0.013 Å, rg(C–N)=1.500±0.005 Å, rg(C–H)=1.095±0.007 Å, ∠BrBBr=110.3±0.3°, ∠CNC=107.8±0.5°. The potential barriers around the N–B bonds in (CH3)3N·BCl3 and (CH3)3N·BBr3 were also estimated to be higher than 18 kcal mol−1 and about 12 kcal mol−1 respectively.
  • Kaoru Onuki, Kazue Kurihara, Yoshinori Toyoshima, Mitsunori Sukigara
    1980 Volume 53 Issue 7 Pages 1914-1917
    Published: 1980
    Released: April 19, 2006
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    The dependence of fluorescence intensity of amphiphilic cyanine dyes on the thermotropic fluid-solid phase transition of lipid bilayer membranes has been investigated. N,N′-dioctadecyl oxacarbocyanine iodide or N,N′-dioctadecyl thiacarbocyanine bromide was incorporated into single lamellar liposomes, and the fluorescence intensity of each dye was observed to be modified considerably by the phase transition of the lipid bilayers. An amphiphilic cyanine dye with single long alkyl chain, N-octadecyl-N′-methyl thiacarbocyanine bromide was also incorporated in the lipid bilayers, but in this case, the phase transition showed little effect on the fluorescence intensity. These results were interpreted in terms of the effect of the bilayer membrane fluidity and rigidity on the rotational motion of the incorporated cyanine dyes. The phase transition parameters were obtained by applying those amphiphilic dyes as the fluorescence probe of the phase transition of the liposomes.
  • Tetsuo Morimoto, Jiro Kishi, Osamu Okada, Toshie Kadota
    1980 Volume 53 Issue 7 Pages 1918-1921
    Published: 1980
    Released: April 19, 2006
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    The interaction of water with the surface of ground calcite was investigated by measuring the water adsorption isotherm and the amount of thermally desorbed molecules in vacuo. The results showed that the surface of ground calcite has chemisorbed water at room temperature which can be completely desorbed by evacuation up to 600 °C, and on which water can be physisorbed in a H2O:OH ratio between 1:2 and 1:1, depending on the conditions of the pretreatment. The isosteric heat of the physisorption of water on the hydroxyls showed that the activity of the adsorption sites for water is reduced by treating the sample at higher temperatures or by washing with water. Moreover, it was found that the surface of the calcite sample starts to release CO2 molecules by heat treatment at relatively low temperatures below 300 °C in vacuo, and that the amount of CO2 increases exponentially with an increase in the temperature.
  • Mineo Takatsuki
    1980 Volume 53 Issue 7 Pages 1922-1930
    Published: 1980
    Released: April 19, 2006
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    The absorption spectra of three dyes, 9-aminoacridine (AA), Crystal Violet (CV), and Trypaflavine (TF), were measured in the presence of sodium polyphosphate (NaPP). The optical titrations were performed at phosphate residue-to-dye ratios between 26.6 and 2130 for AA, between 42.6 and 788 for CV, and between 53.9 and 1120 for TF. Using a model in which the condensation of dyes to a poly electrolyte and the bound monomer\ ightleftharpoons bound aggregate equilibrium in the vicinity of the polymer are assumed, the extended principal component analysis was applied to the observed spectra of each dye–NaPP system. The equilibrium constants and the pure spectra of bound dye species were determined. Both the bound monomer and the bound dimer were present in the AA–NaPP system, while the bound monomer, bound dimer, and bound tetramer were present in both CV– and TF–NaPP systems. In all the cases, the absorption spectrum of the bound monomer showed a slight bathochromic shift. The absorption spectrum of the bound dimer of AA showed a considerable bathochromic shift without any new band, while the spectrum of the bound dimer and bound tetramer of CV and TF showed metachromasy bands in wavelength ranges both shorter and longer than the peak wavelength of free CV and TF.
  • Tetsuo Suzuki, Yumiko K. Tsutsui, Tsunetake Fujiyama
    1980 Volume 53 Issue 7 Pages 1931-1936
    Published: 1980
    Released: April 19, 2006
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    The infrared absorption spectrum for the ν1 fundamental of chloroform or chloroform-d shows strong asymmetry, with a remarkable tailing on the high-frequency side. The observed band-width of the ν1 fundamental of chloroform-d is significantly narrower than that of chloroform. These asymmetric band profiles of the ν1 bands of chloroform and chloroform-d can be interpreted in terms of the existence of two different types of chloroform molecules. One is a molecule which interacts with another molecule, and the other is a non-interacting molecule. The isotope effect on the band-width can be explained in terms of the difference in the reduced mass for chloroform and chloroform-d.
  • Masanao Kato
    1980 Volume 53 Issue 7 Pages 1937-1941
    Published: 1980
    Released: April 19, 2006
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    An expression for excess volumes of multi-component mixtures was derived, and its applicability to the experimental values of ternary mixtures was demonstrated. It was found, in 1,2-dichloroethane+benzene+cyclohexane, ethanol+benzene+cyclohexane and ethanol+acetone+cyclohexane mixtures, that the agreements between the calculated and the experimental values were satisfactory.
  • Tadaaki Kakutani, Mitsugi Senda
    1980 Volume 53 Issue 7 Pages 1942-1948
    Published: 1980
    Released: April 19, 2006
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    Theoretical expressions are presented of the a.c. polarization and of the a.c. polarography and voltammetry for a two-step surface redox reaction (Oad+n1e\ ightleftharpoonsSad,Sad+n2e\ ightleftharpoonsRad) in which the charge transfer reactions take place exclusively between the adsorbed reactants Oad, Sad, and Rad, and all the reactants are adsorbed so strongly that the amount of O, S, or R brought to or removed from the electrode surface can be neglected. The interaction between the adsorbed reactants is assumed to be expressed by Frumkin’s a-parameters. The effect of the double layer impedance is taken into account. Several simplified cases are discussed in detail.
  • Kenji Yokoyama, Shiro Maeda
    1980 Volume 53 Issue 7 Pages 1949-1955
    Published: 1980
    Released: April 19, 2006
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    Resonance Raman spectrum of 1,2,4,5-tetracyanobenzene anion radical (TCNB) was measured and compared with that of the neutral molecule (TCNB). Particularly, a Raman line assigned to C1C2 stretching vibration decreased its frequency remarkably when TCNB was converted to TCNB. This decrease indicated that the lowest unoccupied molecular orbital (LUMO) of TCNB had a node on C1C2 bonding, showing that the LUMO belonged to an au species. Furthermore vibrational analyses of TCNB and TCNB were carried out and the assignment of their Raman lines was confirmed.
  • Akio Furusaki, Nobuyuki Hamanaka, Takeshi Matsumoto
    1980 Volume 53 Issue 7 Pages 1956-1960
    Published: 1980
    Released: April 19, 2006
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    The detailed molecular geometry of grayanotoxin II has been examined by means of X-ray crystallographic analysis. The crystals are orthorhombic, with four molecules in a unit cell with dimensions of a=10.040, b=26.517, and c=6.672 Å; the space group is P212121. 1908 unique intensity data were collected on a four-circle diffractometer with LiF-monochromated Cu Kα radiation. The structure was solved by the Monte Carlo direct method, using the 20 strongest reflections as the starting set; the 3rd random phase set led to the correct solution. The R value reached 3.8% by repeated block-diagonal least-squares refinements. The A, B, C, and D rings take envelope, twist-chair, chair, and half-chair conformations respectively. The conformation of the B ring closely resembles the preferred one of cycloheptane itself. The crystal consists of hydrogen-bonded double molecular layers piled parallel to the (010) plane.
  • Masatatsu Suzuki, Hajime Kanatomi, Hiroyuki Koyama, Ichiro Murase
    1980 Volume 53 Issue 7 Pages 1961-1964
    Published: 1980
    Released: April 19, 2006
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    A series of five-coordinate copper(II) complexes with tripod ligands, tris(2-alkylthioethyl)amines (NS3–R, R=CH3, C2H5, n-C3H7, i-C3H7, and t-C4H9), [Cu(NS3–R)L](ClO4)n, where L represents Cl, Br, I, NCS, im(imidazole), py(pyridine) and H2O, n=1 or 2 were prepared and characterized. The electronic, infrared and ESR spectral data suggest that [Cu(NS3–Me)im](ClO4)2 and [Cu(NS3–Me)OH2](ClO4)2 have a five-coordinate square pyramidal geometry, the other complexes having distorted trigonal bipyramidal or trigonal bipyramidal geometry. The copper(I) complexes with NS3–Me, [Cu(NS3–Me)]ClO4 and [Cu(NS3–Me)NCS] were also prepared and characterized.
  • Bernd M. Rode, Ryo Fujikura, Shizuo Fujiwara
    1980 Volume 53 Issue 7 Pages 1965-1967
    Published: 1980
    Released: April 19, 2006
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    Quantum chemical model calculations have been performed using an STO-3G basis set for linear water polymers under the influence of electrostatically approximated cations and anions. It is found that the influence of the cations on the ligand chains can be described properly as a purely electrostatic interaction from the third water molecule on. The mutual influencing of cation and anion in ion pairs separated by more than one solvent molecule seems to be also a merely electrostatic one. An estimation of the range of these electrostatic forces is given.
  • Mitsutomo Tsuhako, Naoko Fujita, Akiko Nakahama, Tsuneo Matsuo, Masami ...
    1980 Volume 53 Issue 7 Pages 1968-1972
    Published: 1980
    Released: April 19, 2006
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    The reaction of cyclo-triphosphate(P3m) with L-valine in an aqueous solution was studied by means of anionexchange chromatography, paper chromatography, chemical analysis for phosphorus and valine, IR spectroscopy, and ninhydrin reaction. 1) P3m reacted with L-valine at pH 10–12 to form an unknown compound, the amount of which reached about 22% at pH 12 and about 9% at pH 10. This compound decomposed into orthophosphate(P1) and valine at a lower pH. 2) The unknown compound was proved to be a P1-derivative of valine, (Remark: Graphics omitted.), which has a P–N bond in its molecule. 3) In the reaction of P3m with L-valine at pH 10, in addition to the unknown compound, small amounts of tetra(P4) and pentaphosphate(P5) were produced. 4) The disappearance rate of P3m in this reaction was first-order, and its rate constants were 0.317 and 0.138 d−1 at pH 12 and 10 respectively at room temperature. 5) Short-chain phosphates, such as P1 pyro (P2), and triphosphate(P3), did not react with L-valine at all. 6) The mechanism of the reaction of P3m with L-valine was discussed.
  • Osamu Yamaguchi, Muneaki Kamata, Kiyoshi Shimizu
    1980 Volume 53 Issue 7 Pages 1973-1975
    Published: 1980
    Released: April 19, 2006
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    A new metastable SrB2O4 was formed by heating amorphous material prepared by the simultaneous hydrolysis of strontium and boron alkoxides. Crystallization isotherms were obtained by means of the Avrami equation ln(1−α)=−ktn with n=2, the activation energy being determined to be 351 kJ/mol. The kinetics of transformation of metastable into stable SrB2O4 is interpreted by the first-order equation −ln(1−α)=kt. Activation energies are 498 kJ/mol and 343 kJ/mol for initial and final stages, respectively.
  • Katsuma Hiraki, Keiichi Sugino, Masayoshi Onishi
    1980 Volume 53 Issue 7 Pages 1976-1981
    Published: 1980
    Released: April 19, 2006
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    A chloro-bridged organopalladium(II) complex, di-μ-chloro-bis(3-t-butylthio-2-methoxy-2-methylpropyl-1-C,S)dipalladium(II) reacted with an electron-rich olefin, bis(1,3-diphenyl-2-imidazolidinylidene) (L2) to yield a new dinuclear carbene complex, di-μ-chloro-bis(1,3-diphenyl-2-imidazolidinylidenato-2-C,2′-C)dipalladium(II) (4). Complex 4 was treated with thallium acetylacetonate, triisopropyl phosphite, 4-picoline, silver acetate, and L2, affording the corresponding new carbene complexes. On the basis of spectroscopic properties, these complexes were ascribed to new complexes containing cyclopalladated chelate structure in the carbene ligand. Di-μ-chloro-bis(1-3-η3-methallyl)dipalladium(II) and di-μ-chloro-bis(6-exo-methoxy-3a,4,7,7a-tetrahydro-endo-4,7-methanoindene-endo-5σ, 2π)dipalladium(II) reacted with L2 to give new mononuclear (carbene)chloropalladium(II) complexes possessing a σ,π-methallyl group and a π-coordinated-chelating alkyl-palladium σ-bond, respectively.
  • Makoto Takagi, Setsuo Goto, Masato Tazaki, Tsutomu Matsuda
    1980 Volume 53 Issue 7 Pages 1982-1987
    Published: 1980
    Released: April 19, 2006
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    The irradiation of organic disulfides in aldehyde solvents resulted in the reductive fission of the S–S linkage, giving an equimolar mixture of the corresponding thiol and the thiol acylate in a good yield. The cyclic disulfides gave mono S-acylated dithiols. The reaction proceeded by means of the photo-initiated radical chain mechanism, and AIBN (azobisisobutyronitrile) effected the same reaction under thermal conditions.
  • Akihiko Ueno, Keiko Takahashi, Jun-ichi Anzai, Tetsuo Osa
    1980 Volume 53 Issue 7 Pages 1988-1992
    Published: 1980
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    Copolymers of β-benzyl L-aspartate and β-[p-(phenylazo)phenethyl] L-aspartate were prepared and their conformations studied by circular dichroism (CD) spectroscopy. The copolymers with less than 40% azo amino acid residues were found to be left-handed (LH) helical, those with more azo amino acid residues right-handed (RH) helical in 1,2-dichloroethane (DCE) solution. The former undergo LH helix→random coil transition on addition of hexafluoro-2-propanol (HFIP) to their DCE solutions, the latter RH helix→LH helix→random coil transition on addition of HFIP. All polymers in DCE exhibit a negative CD band in the side-chain n-π* transition region. The side-chain π-π* CD band was observed only for the copolymers with the highest azo amino acid residues (67%). Its absolute ellipticity decreases with increasing HFIP content, finally disappearing at 10% HFIP. The sign of the n-π* CD band of the copolymer remains negative irrespective of the helix reversion, its absolute ellipticity being unchanged below 10% HFIP and decreasing on further increase in HFIP content. The results suggest solvent-induced changes in orientation or mobility of the side-chain phenylazo moieties.
  • Ryoichi Akaba, Katsumi Tokumaru, Tsunetoshi Kobayashi
    1980 Volume 53 Issue 7 Pages 1993-2001
    Published: 1980
    Released: April 19, 2006
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    The electronic structures and molecular conformations of N-benzylideneaniline and its several derivatives bearing 2-methyl, 2,6-dimethyl, and/or 4-nitro groups on the anilino benzene ring (ring A) have been investigated by electronic absorption spectroscopy combined with CNDO/S CI calculations. The lower energy bands are assigned and the molecular conformations are estimated. The results show that the 4-nitro derivatives as well as the 2,6-dimethyl derivatives take considerably twisted conformations.
  • Ryoichi Akaba, Katsumi Tokumaru, Tsunetoshi Kobayashi, Chikatoshi Utsu ...
    1980 Volume 53 Issue 7 Pages 2002-2006
    Published: 1980
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    Electronic structures and molecular conformations have been studied for N-benzylideneaniline and its 2-methyl, 2,6-dimethyl, and their 4-nitro derivatives by photoelectron spectroscopy. The lower energy bands are analyzed in detail, and the twist angles θN of the anilino benzene rings (ring A) about the carbon-nitrogen bonds are estimated by examining the effect caused by a methyl substitution. It is concluded that N-benzylidene-4-nitroaniline takes a more twisted conformation than N-benzylideneaniline.
  • Suketaka Ito, Akikazu Kakehi, Toshiyuki Matsuno, Jun-ichi Yoshida
    1980 Volume 53 Issue 7 Pages 2007-2011
    Published: 1980
    Released: April 19, 2006
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    3-Phenyl[1,2,4]triazolo[4,3-a]pyridines were obtained in good yields from N′-[α-(1-pyridinio)benzylidene]benzenesulfonohydrazidates, generated from 2-unsubstituted pyridines and N-(phenylsulfonyl)benzohydrazonoyl chloride (2), by oxidation with chloranil. The reaction of quinoline and isoquinoline with 2 gave 1-phenyl-3-phenylsulfonyl-3,3a-dihydro[1,2,4] triazolo [4,3-a]quinoline and 3-phenyl-1-phenylsulfonyl-1,10b-dihydro [1,2,4]triazolo[3,4-a]isoquinoline respectively, both in good yields; they aromatized to the corresponding triazoles by the 1,2-elimination of benzenesulfinic acid on heating.
  • Ken-ichi Onuma, Tomiyasu Ito, Asao Nakamura
    1980 Volume 53 Issue 7 Pages 2012-2015
    Published: 1980
    Released: April 19, 2006
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    The effect of triethylamine on asymmetric hydrogenation has been studied using the cationic rhodium complex of (1S,2S)-1,2-bis(diphenylphosphinamino)cyclohexane or (2S,3S)-2,3-bis(diphenylphosphinamino)butane as a catalyst. By the addition of triethylamine, higher optical yields are achieved in the hydrogenation of (Z)-α-acetamidocinnamic acid and itaconic acid and higher conversion rates are obtained in the hydrogenation of (E)-2-methylcinnamic acid, mesaconic acid, and citraconic acid. The specific effect of triethylamine on the substrates with a carboxyl group may be explained by the ionization of the carboxyl group, which coordinates the catalytic rhodium complex firmly.
  • Ken-ichi Onuma, Tomiyasu Ito, Asao Nakamura
    1980 Volume 53 Issue 7 Pages 2016-2019
    Published: 1980
    Released: April 19, 2006
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    The asymmetric hydrogenation of α-acylaminocinnamic acids with the rhodium complex of (1R,2R)-1,2-bis(N-diphenylphosphino-N-methylamino)cyclohexane has been reported to give preferentially (S)-amino acids. On the contrary, it has been found that the enantiomeric (R)-amino acids are obtained by hydrogenation with the rhodium complex of (1R,2R)-1,2-bis(diphenylphosphinamino)cyclohexane. The study of the inversion of the stereoselectivity of the rhodium complex of (1R,2R)-1,2-bis(diphenylphosphinamino)cyclohexane by the N-methylation of the ligand in asymmetric hydrogenation has been described. From stereochemical considerations, the chiral helical conformation of the phenyl groups attached on the phosphorus in bisphosphine-rhodium complexes may be responsible for the induced chirality of the product of the hydrogenation. A complex with a left-handed helicity would give (R)-amino acid, and a complex with a right-handed helicity would give (S)-amino acid. The effects of the solvents and substrate structures on the optical yields are also discussed.
  • Kazuya Kurata, Takashi Amiya
    1980 Volume 53 Issue 7 Pages 2020-2022
    Published: 1980
    Released: April 19, 2006
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    The investigation of the red alga Polysiphonia urceolata afforded a new bromophenol, 3,3′-dibromo-4,4′,5,5′-tetrahydroxybibenzyl. The structure was elucidated by a combination of spectroscopic methods and chemical transformations. Besides this compound, seven known bromophenols were isolated.
  • Shigeru Oae, K\={o}ichi Shinhama, Yong Hae Kim
    1980 Volume 53 Issue 7 Pages 2023-2026
    Published: 1980
    Released: April 19, 2006
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    t-Butyl thionitrate have been found to be an excellent diazotizing reagent of arylamines in aprotic nonpolar media, affording eventually such products as aryl chlorides, aryl bromides, aryl iodides, biphenyls, and aryl methyl sulfides in the presence of CCl4, CHBr3, I2, benzene, and dimethyl disulfide, respectively, via extrusion of N2.
  • Toshihide Hatsui, Hitoshi Takeshita
    1980 Volume 53 Issue 7 Pages 2027-2030
    Published: 1980
    Released: April 19, 2006
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    The singlet-oxygen oxidation of a spirocyclic vinylcyclopropane in the presence of diphenyl sulfide, a reducing agent, was shown to form a cis-glycol by the O–O cleavage of dioxetane. The determination of the stereochemistry of isomeric glycols obtained by chemical derivation led to a revision of the structure of the azido alcohol formed during the photosensitized oxygenation in a presence of the azide ion to the trans-derivative.
  • Takeo Katsushima, Ken’ichiro Maki, Ryohei Yamaguchi, Mituyosi Ka ...
    1980 Volume 53 Issue 7 Pages 2031-2035
    Published: 1980
    Released: April 19, 2006
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    Bromination of tricyclo[5.3.1.04,9]undeca-2,5-diene gave endo-2,endo-6- and endo-2,exo-6-dibromotetracyclo[5.3.1.03,5.04,9]undecanes along with syn-11,endo-2-dibromotricyclo[4.3.1.13,8]undec-4-ene (10a) in a ratio of 3:3:1. A thermal treatment of the mixture of these dibromides at 140–150 °C induced a skeletal rearrangement to afford 10a and syn-11,exo-2-dibromotricyclo[4.3.1.13,8]undec-4-ene (10b) in 87% yield (10a:10b=2:5). The new “non-bridgehead” 2,11-dehydrohomoadamantane was obtained by the hydrogenation of 10a and 10b followed by Wurtz type reductive cyclization. The unsaturated analogue, 2,11-dehydrohomoadamant-4-ene was also synthesized from 10a and 10b by the similar cyclization reaction.
  • Osamu Hara, Kagetoshi Yamamoto, Ichiro Murata
    1980 Volume 53 Issue 7 Pages 2036-2039
    Published: 1980
    Released: April 19, 2006
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    The acetolysis of 6-mesyloxymethyl-6H-benzo[cd]pyrene (6) gave 7,7a-dihydrospiro[benzo[ghi]perylene-5-(6H),6′-[6H]benzo[cd]pyrene] (13), whereas, on formolysis, 6 gave spiro[benzo[ghi]perylene-5(6H),6′-[6H]benzo[cd]-pyrene], 6-hydroxymethyl-6H-benzo[cd]pyrene, and 6-methyl-6H-benzo[cd]pyrene as well as 13. It might reasonably be supposed that the formation of 13 proceeds in a process involving four steps: (i) the formation of the intermediate 6H-6-benzo[cd]pyren-6-ylmethyl cation (8); (ii) the conversion of 8 into the reactive 6-methylenebenzo[cd]pyrene (5) by the loss of a proton; (iii) the head-to-head self-Diels-Alder dimerization of 5 to the initial dimer, 6,7-dihydrospiro[benzo[ghi]perylene-5(4aH),6′-[cd]benzo[cd]pyrene], and (iv) a 1,3-hydrogen shift to form 13. When 6-methylbenzo[cd]pyren-6-yl tetrafluoroborate (7) was treated with triethylamine in chloroform, the spiro-dimer, 13, was also obtained. The reaction of 7 with triethylamine in the presence of dimethyl acetylenedicarboxylate resulted in the formation of dimethyl benzo[ghi]perylene-5,6-dicarboxylate. These results strongly suggest the intermediate formation of 5 as a reactive compound.
  • Toshio Fuchigami, Tomoyasu Iwaoka, Tsutomu Nonaka, Taro Sekine
    1980 Volume 53 Issue 7 Pages 2040-2045
    Published: 1980
    Released: April 19, 2006
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    Intramolecular N,N-coupling by the electrochemical oxidation of cyclic and open-chain diamines such as 3,3,7,7-tetraethylperhydro-1,5-diazocine (1) and N,N-dimethyl-2,2-diethyl-1,3-diaminopropane (2) was investigated with the use of platinum, silver, nickel, and carbon anodes. In the case of 1, cyclic hydrazine derivatives, 3,3,7,7-tetraethyl-1,5-diazabicyclo[3.3.0]octane and 1-(2-ethyl-2-formylbutyl)-4,4-diethyl-4,5-dihydropyrazole, were formed in high current efficiency. In the case of 2, the corresponding hydrazines, 1,2-dimethyl-4,4-diethylpyrazolidine and 1-methyl-3,3-diethyl-4,5-dihydropyrazole, were obtained in low current efficiency, because C–N bond cleavage took place before N,N-coupling. A carbon anode was found to be effective for N,N-coupling of such diamines. Chemical oxidative N,N-coupling of 1 and 2 was studied by using sodium peroxodisulfate and lead tetraacetate.
  • Hiroyuki Nakazumi, Akira Asada, Teijiro Kitao
    1980 Volume 53 Issue 7 Pages 2046-2049
    Published: 1980
    Released: April 19, 2006
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    The products formed by the reaction of benzenethiols with diketene in the presence of H2SO4 are (E)-β-(arylthio)crotonic acids (2) and/or isomeric (Z)-β-(arylthio)crotonic acids and not, as has been reported, S-phenyl 3-oxobutanethioates (1). Compounds 1ak, as the precursor of thiocoumarins, were prepared from benzenethiols and diketene in the presence of triethylamine. The reaction of 1 with various condensing agents has been examined to prepare 2H-1-benzothiopyran-2-ones (thiocoumarins). It is found that 4-methyl(thiocoumarins) were conveniently prepared by the reaction of 1 with anhydrous aluminium chloride in yields of 16–48%. When 1 was treated with PPA, isomeric 2-methyl(thiochromones) were preferentially obtained in yields of 5–66%, and compound 2 was isolated as an intermediate. The spectral characteristics of 4-methyl(thiocoumarins) have also been described.
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