Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 50 , Issue 7
Showing 1-50 articles out of 61 articles from the selected issue
  • Tsutomu Minato, Satoshi Inagaki, Hiroshi Fujimoto, Kenichi Fukui
    1977 Volume 50 Issue 7 Pages 1651-1656
    Published: 1977
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    The path of suprafacial 1,3-sigmatropic rearrangement is studied with the INDO-CI and INDO LMO methods. The methyl migration has been found to be represented by successive 1,2-shifts with a biradicaloid transition state. The interaction between the singly occupied MO’s of allyl and methyl fragments is suggested to be responsible for the determination of the path. A subsidiary orbital also plays a part. On the other hand, the chlorine migration has been shown to be a direct 1,3-shift. The interaction between the lowest unoccupied MO of the allyl cationic part and the highest occupied MO of the remaining part, chloride anion, has been found to govern the path of chlorine migration. The lone pair electrons of the migrating fragment makes the successive 1,2-shifts quite unlikely in the 1,3-suprafacial chlorine rearrangements.
  • Hiroyuki Horiguchi, Soji Tsuchiya
    1977 Volume 50 Issue 7 Pages 1657-1660
    Published: 1977
    Released: April 19, 2006
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    In order to determine the branching ratio for Hg(63P1) deactivation to the 63P0 and 61S0 states in CO or NO, a modulation technique was utilized. The intensity of 253.7-nm radiation was modulated at a frequency in the range from 0.1 to 20 kHz, and the resulting a.c. component of the Hg(63P1 or 63P0) concentration was measured by monitoring the absorption of the 435.8- or the 404.7-nm emission line from an Hg discharge lamp. The lower detection limit of excited Hg atoms was 107 cm−3 in this experimental method. On the basis of the Hg(63P0) concentration relative to that of Hg(63P1) in an Ar+CO or NO mixture including information on the phase delay, the 63P1→63P0 transition rate could be determined; the 63P1→63P0 cross section was found to be 22.4 Å2 for CO and 7.1 Å2 for NO and the 63P0→61S0 cross section to be 1.80 Å2 for CO and 37 Å2 for NO at room temperature.
  • Hiroyuki Horiguchi, Soji Tsuchiya
    1977 Volume 50 Issue 7 Pages 1661-1664
    Published: 1977
    Released: April 19, 2006
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    The absorption intensities of the 435.8- and 404.7-nm lines by Hg(63P1 and 63P0) atoms were calculated taking into account the hyperfine structure under the assumption of a Doppler spectral line shape. The calculated values were tested by comparison with experimental absorption of the line in an Ar+N2+Hg mixture illuminated by 253.7-nm radiation. This procedure led to the conclusion that the ratio of the spectral half-width of the 404.7-nm line from a low-pressure Hg lamp to that of the Hg(63P0) absorption line should be 2.25±0.25 instead of the value of 5 determined in the previous experiment. On the basis of this value, the quenching cross sections of the excited Hg atoms reported in the previous paper were revised. The corrections are generally less than 20%, so that it is not necessary to change the previous conclusions.
  • Tsutomu Mimura, Michiya Itoh, Toshiaki Ohta, Toshihiko Okamoto
    1977 Volume 50 Issue 7 Pages 1665-1669
    Published: 1977
    Released: April 19, 2006
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    Semiempirical SCF-MO-CI caluculation was carried out for the 1,4-dicyanobenzene (DCB) and naphthalene system which is known to form exciplex (DA)* and triple exciplex (D2A)*. Potential energy curves of the electronic interactions between excimer and electron acceptor molecule, and between exciplex and electron donor molecule were constructed. The results show that the array of component molecules in the triple exciplex is DDA, and the stabilization energy of triple exciplex is ≈0.4 eV from the excimer and ≈0.2 eV from the exciplex. They are in line with results reported on the experiment of exciplex and triple exciplex formation.
  • Hidetoshi Karasawa, Eung-Ryul Kim, Shin Sato
    1977 Volume 50 Issue 7 Pages 1670-1673
    Published: 1977
    Released: April 19, 2006
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    The γ-radiolyses of cyclohexane and 2,2,4-trimethylpentane have been reinvestigated. Bromobenzene was used as the electron scavenger. The analysis of the G-values of benzene obtained at high concentrations of bromobenzene showed that the empirical formula proposed by Hummel for the electron scavenging
    G=G_fi+G_gi{1-exp(-√‾αS)}
    is better than that proposed by Warman et al. The values of Gfi+Ggi thus obtained were 3.7±0.3 for cyclohexane and 3.5±0.2 for 2,2,4-trimethylpentane. The bromobenzene-concentration dependence of the G-values of hydrogen and methane from 2,2,4-trimethylpentane was well explained by the hypothesis that the lifetimes of the 2,2,4-trimethylpentane ion for the decomposition are in the same order as the time needed for the geminate recombination.
  • Toshiko Ogata, Tooru Taga, Kenji Osaki
    1977 Volume 50 Issue 7 Pages 1674-1679
    Published: 1977
    Released: April 19, 2006
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    Mixed crystals of formates, with the general formula of (Cu,MII)(HCOO)2·2H2O, were found to show non-uniform changes in lattice constants with the change in the chemical constitution. The reason for this unusual change was sought in relation to a possible non-uniform distribution of the cations over the two non-equivalent sites for metal ions. A simple model based merely on the difference in the radii of metallic ions did not agree with the results of IR measurements nor with those of an ESR study by Wagner et al. Another model, incorporating the change in the direction of the longest axis of the octahedron coordinating to the Cu2+ ion at the Ml-site, as suggested from the results of a related work (Part II), was found not only to explain the changes in lattice constants, but also to conform with other evidences; it seems to be an essentially correct interpretation.
  • Toshiko Ogata, Tooru Taga, Kenji Osaki
    1977 Volume 50 Issue 7 Pages 1680-1682
    Published: 1977
    Released: April 19, 2006
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    The structure of the 1 : 1 mixed crystal between Cu(HCOO)2·2H2O and Zn(HCOO)2·2H2O has been determined on the basis of 878 visual intensity data. The space group is P21/c, with a=8.77, b=7.25, c=9.17 Å, β=98.0°, and Z=4. The structure is similar to that of Cu(HCOO)2·2H2O, except that the two metal ions are distributed over two metal ion sites, the Cu2+ ions being mostly localized in the [Cu(HCOO)2] sheet, and except that the longest axis of the coordination octahedron around the Cu2+ ion in this sheet is nearly perpendicular to it. It is suggested that the type of sheet found in the mixed crystal as well as in Cu(HCOO)2·4H2O is more favorable than that in Cu(HCOO)2·2H2O for an independent [Cu(HCOO)2] sheet.
  • Seiichiro Koda
    1977 Volume 50 Issue 7 Pages 1683-1686
    Published: 1977
    Released: April 19, 2006
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    NH2(\ ildeA2A1) was produced by photolysis of NH3 on irradiation with vacuum ultraviolet light. The zero pressure lifetimes were evaluated to be ca. 15 μs from the phase lag of the emission excited by modulated Xe and Kr resonance lamps. The quenching rate coefficient of NH2(2A1) for NH3 was determined to be ca. (1.6±0.3)×10−10 cm3/molecule·s.
  • Fumio Kawaizumi, Tuneyuki Noguchi, Yutaka Miyahara
    1977 Volume 50 Issue 7 Pages 1687-1689
    Published: 1977
    Released: April 19, 2006
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    Using a calorimeter composed of a Dewar vessel and a Beckmann thermometer, the specific heat capacities of aqueous solutions of glutaric and malonic acids were measured at 30 °C. Techniques for establishing the temperature gadient between the solution in the Dewar and the outer air bath were adopted. The partial molar heat capacities at infinite dilution were estimated assuming a relation of the form mφCp=bm+cm2. The contributions of the –CH2– and –COOH groups to the partial molar heat capacities in aqueous solution are roughly additive: for –CH2– a positive contribution and for –COOH a negative one. The Δ(=‾Cp2°–Cp2(pure state)) were also calculated and positive and negative values were obtained for Δ(–CH2–) and Δ(–COOH), respectively.
  • Nagamune Nishikido, Ryohei Matuura
    1977 Volume 50 Issue 7 Pages 1690-1694
    Published: 1977
    Released: April 19, 2006
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    In order to divide the inorganic salt effect on the micelle formation of nonionic surfactants into the effects on the hydrocarbon and on the hydrophilic moieties of the surfactant, the critical micelle concentrations(CMC) of nonionic surfactant homologs (8,10,12 methylene and 6 oxyethylene groups) were determined in aqueous salt solutions. The salt-effect parameters of methylene and hexa(oxyethylene) groups were calculated from the CMC data. The orders of both the parameters with respect to the anion obeyed the Hofmeister series. The variation in the extent of the parameters with respect to the cation was much less than that with respect to the anion. These phenomena were discussed in terms of the direct and indirect effects of ions on the water structure around the hydrocarbon and hydrophilic moieties of the surfactants. In addition, the salt effect on the cloud point (CP) and the amount of solubilization toward the Yellow OB dyestuff in aqueous solutions were discussed in connection with the salt effect on the hydrophilic moiety.
  • Tsutomu Okuda, Isamu Tomoyasu, Koji Yamada, Hisao Negita
    1977 Volume 50 Issue 7 Pages 1695-1697
    Published: 1977
    Released: April 19, 2006
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    The NQR sepctra due to 81Br and 127I in potassium dibromoiodate and its monohydrate were observed, and the Zeeman effect of 81Br NQR in the monohydrate was examined. The resonance lines indicate that both compounds have two kinds of dibromoiodate ions and that these ions in the anhydride are slightly asymmetric, while those in the monohydrate are symmetric. The difference in frequency between the two resonance lines due to each resonant nucleus in the monohydrate is explained in terms of the I···Br intermolecular interaction. The charge distributions in both compounds were evaluated to be about −0.6e and 0.2e on the terminal and central atoms respectively.
  • Yoshihumi Kusumoto, Yasuhiko Gondo, Hiroyasu Sato, Yoshiya Kanda
    1977 Volume 50 Issue 7 Pages 1698-1701
    Published: 1977
    Released: April 19, 2006
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    Temperature and concentration dependences of the delayed luminescence observed in the naphthalene (guest)–biphenyl (host) mixed crystal system have been studied. The presence of the temperature-independent delayed fluorescence (TIDF) and its significance in the evaluation of activation energy have also been confirmed in this system as in the case of the benzo[f]quinoline–biphenyl system previously reported, and the generality of the existence of TIDF as well as its significance in relation to activation energy has been suggested. In addition, some remarks have been made on the nature of TIDF and the decay behavior.
  • Naoto Arai, Michio Sorai, Hiroshi Suga, Syûzô Seki
    1977 Volume 50 Issue 7 Pages 1702-1709
    Published: 1977
    Released: April 19, 2006
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    Construction of an isoperibol-type calorimeter with a 3He cryostat is described. A system of charcoal-adsorption-pump is adopted. A Ge-thermometer used in the heat capacity measurements is calibrated in the temperature range from 0.4 to 1.5 K against the magnetic susceptibility of chromium potassium alum. The precision and the accuracy of the calorimeter is ascertained by the heat capacity measurement of the 1965 Calorimetry Conference Copper Standard (T-8.6) in the temperature range from 0.420 to 19.46 K. The deviation of the experimental points from the “copper reference equation” is within the experimental error of ±2.5% between 0.4 and 0.9 K, ±1.5% between 0.9 and 1.5 K, ±1.2% between 1.5 and 4 K, and ±0.6% between 4 and 20 K. The highest deviation of absolute value of the present heat capacity data of copper is 1.86% smaller than the “selected values (Furukawa et al.)” around 6 K. This difference may be primarily attributable to the NBS-65 temperature scale adopted in the present experiment.
  • Yuji Ohashi, Yoshio Sasada
    1977 Volume 50 Issue 7 Pages 1710-1715
    Published: 1977
    Released: April 19, 2006
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    The structure of methyl (R(+)-α-methylbenzylamine)bis(dimethylglyoximato)cobalt(III) benzene solvate has been determined by X-ray crystal analysis. The crystal is orthorhombic; space group, P212121; Z=4 with a=14.074(1), b=14.390(1), and c=12.202(1) Å. The structure was deduced by the heavy-atom method and refined by the block-diagonal least-squares method to a final R value of 0.063 for 1413 observed reflections. The symmetry of the bis(dimethylglyoximato)cobalt moiety has been lowered from D2h to C2h as a result of the steric repulsion from optically active amine. It is proposed that this deformation is a factor inducing the asymmetry in the hydrogenation catalyzed by the complex of bis(dimethylglyoximato)cobalt and the active amine.
  • Sadakatsu Nishikawa, Unpei Otani, Mitsuo Mashima
    1977 Volume 50 Issue 7 Pages 1716-1719
    Published: 1977
    Released: April 19, 2006
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    Ultrasonic absorptions in aqueous solutions of allylamine have been measured in the frequency range from 8.5 to 220 MHz at 20 °C. Only a single relaxational absorption has been observed in the concentration range from 0.0562 to 4.00 M; this absorption has been attributed to the proton-transfer reaction. The rate constants and the standard volume change due to the reaction have been determined, and the results are compared with those for aqueous solutions of other amines previously published. It has been elucidated from the ultrasonic absorption data that the presence of the intermediate in the proton-transfer reaction is required in order to analyze the ultrasonic absorption mechanisms quantitatively. The hydrophobic effect in the aqueous solutions of amines has also been discussed.
  • Izumi Maki, Kazuo Kitaura, Kichisuke Nishimoto
    1977 Volume 50 Issue 7 Pages 1720-1725
    Published: 1977
    Released: April 19, 2006
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    The effective π-electron Hamiltonian for the excited molecule has been derived from the singly excited configuration interaction method (SECI) considering Σ-Π interaction. In this paper, the zero-differential overlap (ZDO) approximation has been employed. Then, in SECI scheme, π-π* and σ-σ* configurations interact through the exchange type MO-integrals over π- and σ-MO’s. As the result, only the excited singlet states are modified by Σ-Π interaction. So that the triplet states remain unchanged by this type of interaction.
    When the ZDO approximation is employed, the effective electron interaction over AO’s, \ ildeγμν, can be derived. It is found that \ ildeγμν’s are represented approximately in terms of topological matrix, so named ‘bond index matrix’.
  • Genshiro Fujii, Ichimin Shirotani, Hiroshi Nagano
    1977 Volume 50 Issue 7 Pages 1726-1730
    Published: 1977
    Released: April 19, 2006
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    Temperature and pressure dependence of the electrical conductivity of NMP(I)–, NMP(II)–, Rb(I)– and Rb(II)–TCNQ single crystals was studied. NMP(I)–TCNQ showing diffuse streaks was found to have a semiconductive behavior at atmospheric pressure and no conductive maximum appeared at low temperatures. Moreover the metallic behavior was not shown even at 100 kbar. The crystal structure of NMP(II)–TCNQ is not similar to that of NMP(I)–TCNQ. The difference of physical properties of two phases is discussed. The anomalous electrical behavior in the pressure range from 1 bar to 40 kbar was observed for Rb(I)–TCNQ. The resistivity of Rb(II)–TCNQ decreased monotonously with increasing pressure. The magnitude of their activation energies was 0.15 eV for Rb(I) salt and 0.11 eV for Rb(II) salt at 100 kbar. The insulator to metal transition could not be observed at least up to 100 kbar.
  • Harumichi Kobashi, Hitoshi Gyoda, Toshifumi Morita
    1977 Volume 50 Issue 7 Pages 1731-1738
    Published: 1977
    Released: April 19, 2006
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    The behavior of electronically excited chloranil interacting with the titled vinyl compounds and solvents has been studied by means of the nanosecond laser photolysis technique. Semiquinone radicals and/or chloranil anions have been detected as transients except in the system containing styrene. Careful observation and analysis of the kinetic behavior of the transient absorptions reveal that these transients are brought about by the interaction of excited triplet state of chloranil with vinyl monomers and/or solvents. The logarithms of the quenching rate constants and rate constants of the formation of transients are linearly related to the ionization potentials of the vinyl monomers and solvents used. The mechanisms of the triplet quenching and transient formation can reasonably be interpreted by taking the relaxed triplet-state complex with a charge-transfer character into account as the precursor leading to the production of semiquinone radicals, chloranil anions, and other intermediate compounds.
  • Tsutomu Mimura, Michiya Itoh
    1977 Volume 50 Issue 7 Pages 1739-1742
    Published: 1977
    Released: April 19, 2006
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    Exciplex (DA)* and triple exciplex (DDA)* formation between 1,4-dicyanobenzene (DCB) and alkylnaphthalenes was investigated by steady-state and nanosecond time-resolved fluorescence spectroscopies at room temperature. Typical two-component decay of the exciplex and the fluorescence rise of the triple exciplex were observed in dioxane solutions of DCB and several alkylnaphthalenes. The results imply a significant dissociation process of (DDA)* to (DA)*. Triple exciplex formation via excimer (DD)* was proposed to be significant in a concentrated solution of alkylnaphthalene (>10−1 M), while the triple exciplex was formed via the exciplex in a dilute solution of the electron donor.
  • Takayoshi Kobayashi, Noboru Hirota
    1977 Volume 50 Issue 7 Pages 1743-1745
    Published: 1977
    Released: April 19, 2006
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    The rate constants of the bimolecular quenching (γ), the hopping rate (λ), and the diffusion coefficient (D) of triplet exciton in crystalline p-dibromobenzene at temperatures between 160 and 77 K were obtained by analyzing the phosphorescence decay curves at high and low density excitations with the use of an N2 laser as an exciting pulsed light source. Estimated values of γ, λ, and D at room temperature (300 K) are (2±1)×10−12 cm3· s−1, 9±4×109s−1, and 2±1×10−4 cm2 s−1, respectively. The activation energy of the exciton hopping was obtained to be 290±50 cm−1. This implies that the triplet exciton in p-dibromobenzene crystal is described in terms of a localized exciton model.
  • Masao Hashimoto
    1977 Volume 50 Issue 7 Pages 1746-1748
    Published: 1977
    Released: April 19, 2006
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    The chlorine NQR frequencies of several benzene derivatives with –CCl3 groups were measured at temperatures above 77 K. For all the compounds studied, the NQR signals of the –CCl3 groups were observed to fade out; the fade-out temperatures (Tf) were in the temperature range of 130–370 K. It was found that the most important factors involved in determining the Tf value are the intramolecular steric hindrance, hyper conjugation, and intermolecular interactions. In some compounds, an increase in the NQR frequency was found to be caused by the intramolecular steric hindrance.
  • Osamu Ohashi, Mamoru Ohnishi, Akira Tagui, Takeshi Sakaizumi, Ichiro Y ...
    1977 Volume 50 Issue 7 Pages 1749-1753
    Published: 1977
    Released: April 19, 2006
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    The microwave spectra of 1-propanethiol and its deuterated species (CH3CH2CH2SD) were measured in the frequency region from 8.5 to 35 GHz. Several a-type R-branch transitions for the ground and excited vibrational states of the normal species and for the ground state of the deuterated species were identified, and the following rotational constants in MHz were obtained: A=23429±653, B=2345.29±0.03, and C=2250.18±0.03 for the ground state of the normal species; A=24483±945, B=2346.30±0.04, and C=2253.91±0.04 for the excited state of the normal species, and A=21758±461, B=2306.71±0.03, and C=2217.79±0.03 for the ground state of the deuterated species. The spectrum assigned to the ground vibrational states has been attributed to the T–G rotational isomer, and the excited vibrational state has been ascribed to the –CH2–CH2– torsional motion.
  • Kiyohiko Tabayashi, Takayuki Fueno, Kenji Takasa, Okitsugu Kajimoto, K ...
    1977 Volume 50 Issue 7 Pages 1754-1757
    Published: 1977
    Released: April 19, 2006
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    The thermal decomposition of hydrogen cyanide diluted to 0.2, 0.5, and 1.0 mol% in argon was studied behind incident shock waves over the temperature range 2600–3600 K. The decomposition process was followed by monitoring the CN X2Σ+-B2Σ+ (0-0) absorption centered at 3883 Å. The bimolecular rate constants for the reaction HCN+Ar→H+CN+Ar were obtained from the initial slopes of absorption; k1=(1.26±0.28)×1016exp[–(99.69±1.39)kcal mol−1/RT] cm3 mol−1 s−1. The kinetic results are well fitted by the classical collision-theory expression, k1=λ(Zn!)(ERT)nexp(–ERT), with λ=0.22, n=3.5, and E=D0(H–CN)= 118.7 kcal/mol. The overall absorption profiles were found to be explicable on the basis of the reaction scheme involving the homorecombinations of H and CN as well as the chain reaction with H and CN as carrier species.
  • Tomitsugu Taketatsu
    1977 Volume 50 Issue 7 Pages 1758-1761
    Published: 1977
    Released: April 19, 2006
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    Aqueous solutions of pH 1–3 containing Chlorophosphonazo III chelates of lanthanoids give an absorption spectrum of the α-type, the spectrum showing two maximum peaks at approximately 620 and 670 nm, in the presence of an excessive amount of the reagent. However, the chelates of heavier lanthanoids give an absorption band of the β-type, which extends from 700 to 800 nm with a maximum at 745 nm, with an increase in the mole ratio of the metal against the reagent. A dark-violet precipitate forms from the solution, giving the β-type spectrum under certain experimental conditions. The combining ratio of the metal against the reagent in the precipitate is estimated to be 1:1. Since a reaction rate from the α-type to the β-type corresponds to the second order, the combining form between the metal and the reagent in the β-type chelate is assumed to be 2:2, i.e., a dimer. The chelates of lanthanum to samarium do not give the β-type spectrum under the same conditions.
  • Masakatsu Saeki, Enzo Tachikawa
    1977 Volume 50 Issue 7 Pages 1762-1766
    Published: 1977
    Released: April 19, 2006
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    The reactions of 125I obtained from the 125Xe(EC)125I process with methane have been investigated. It was confirmed that electron scavengers, such as I2, SF6, and O2, play an important role. The main product is only CH3125I, the yield decreasing significantly with the concentration of Xe. By adding various additives, the yield of CH3125I in the presence of trace amount of I2 was assigned as follows: 8.7±6.7% by the hot atom reaction, 35.8±8.0% by 125I+ in the 1D2 state, and 31.5±2.0% by 125I+ in the 3P states. The results are discussed in comparison with those reported on similar reactions utilizing different activation processes. Chemical sequences of the formation of CH3125I are proposed.
  • Katumitu Hayakawa, Makoto Sato
    1977 Volume 50 Issue 7 Pages 1767-1770
    Published: 1977
    Released: April 19, 2006
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    The kinetics of the iodine–formate reaction gives an identical rate equation in several water–alcohol mixed solvents: rate=k[HCOO] [I3]/(a[I]+1). The values of k/M−1 s−1 and 10−3 a/M−1 are 5.5 and 16 in ethanol at 35 °C, 3.6 and 12 in methanol at 30 °C, and 0.06 and 0.7 in water at 30 °C, respectively. The values of a are comparable to the formation constants of I3 in the water–alcohol mixtures. The rate-determining step is the reaction between an iodine molecule and a formate ion. The activation parameters, ΔH\ eweq/kJ mol−1 and ΔS\ eweq/J K−1 mol−1, are 71 and −1 in the 0.95 mole fraction of methanol, 60 and −32 in the 0.92 mole fraction of ethanol, and 75 and −20 in water, respectively. The entropy term contributes to the acceleration by alcohol in the water–methanol mixtures, whereas both the entropy term and the enthalpy term contribute to the acceleration in the water–ethanol mixtures. These effects of the mixed solvents suggest that the specific interactions of the solvent molecule with the reactants and the activated complex, such as a specific solvation or a hydrogen bond, play an important role in the rate-determining step.
  • Hirofumi Takahashi, Yoshinao Oosawa, Akiko Kobayashi, Taro Saito, Yuki ...
    1977 Volume 50 Issue 7 Pages 1771-1775
    Published: 1977
    Released: April 19, 2006
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    The crystal structure of the title compound was solved by single-crystal X-ray diffraction techniques. Crystals are monoclinic, space group P21/c, with cell dimensions a=13.39(5), b=16.88(1), c=19.85(6) Å, β=123.54(1)°, Z=4. The final R was 0.065. The ylide ligand coordinates to palladium through the ylide carbon Pd–C, 2.115(15) Å and phosphine phosphorus Pd–P, 2.230(8) Å forming a six-membered chelate ring. The chelating ligand together with two chlorine atoms forms a square-planar geometry around the palladium. The Pd–Cl distances are discussed in terms of trans-influence of the ylide carbon.
  • Osamu Yamauchi, Takeshi Sakurai, Akitsugu Nakahara
    1977 Volume 50 Issue 7 Pages 1776-1779
    Published: 1977
    Released: April 19, 2006
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    Optical resolution of DL-aspartic acid and DL-glutamic acid (abbreviated as DL-A) has been achieved via formation of ternary copper(II) complexes composed of a DL-A and L-arginine, L-lysine, or L-ornithine (L-B). For every pair of ligands DL-A and L-B, a neutralized solution containing Cu(ClO4)2, DL-A, and L-B in the molar ratio of 1 : 2 : 1 gave the mixed ligand complex abounding in [Cu(D-A)(L-B)] as crystals, from which incorporated A was isolated through a Dowex CCR-2 column after treating with H2S. In a very similar manner D-enantiomerrich B was obtained from DL-B by using an L-A. The optical purities of the resolved amino acids were as high as 90 and 70% for aspartic acid and glutamic acid, respectively, and 40–50% for the basic amino acids. The finding shows that the electrostatic ligand-ligand interactions in the mixed ligand complexes give rise to geometric isomerism around copper(II) and hence preferential formation and crystallization of the meso complexes, [Cu(L-A)(D-B)] and [Cu(D-A)(L-B)], probably with a cis configuration.
  • Taku Kitamura, Yoshiko Sato, Masahiko Saburi, Sadao Yoshikawa
    1977 Volume 50 Issue 7 Pages 1780-1783
    Published: 1977
    Released: April 19, 2006
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    trans-Dinitro and dichloro cobalt(III) complexes containing (S)-2-(methylaminomethyl)pyrrolidine (N-Me-ampr) were prepared. Their stereochemistry differs a great deal from that of other N-methylated 1,2-diamines. The N-Me-ampr complexes prefer the trans,cis instead of the trans,trans configuration, the axial N-methyl groups being fairly stabilized. In the case of the dinitro complex, only one isomer which has the axial N-methyl groups, was isolated, but in the case of the trans-dichloro complex two diastereomers (trans,cis(RR) and trans,cis(SS)) were obtained. These dichloro isomers were slowly converted into an equilibrium mixture in methanol. The CD spectral data of the equilibrium mixture show that the trans,cis(RR) is more stable than the trans,cis(SS) isomer (−ΔG=0.4 kcal/mol).
  • Yoshiaki Kusuyama, Yoshitsugu Ikeda
    1977 Volume 50 Issue 7 Pages 1784-1787
    Published: 1977
    Released: April 19, 2006
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    13CFT NMR spectra have been obtained for ethyl trans-2-substituted cyclopropanecarboxylates. The chemical shifts have been compared with those of saturated and unsaturated compounds and with substituent constants. The chemical shifts of the methylene carbon of the ethyl group have been correlated linearly with σm.
  • Chung-gi Shin, Yoshiaki Sato, Hidetoshi Sugiyama, Katsumi Nanjo, Juji ...
    1977 Volume 50 Issue 7 Pages 1788-1792
    Published: 1977
    Released: April 19, 2006
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    Treatment of t-butyl 2-acetylamino-3-bromo-2-alkenoate with triethylamine gave t-butyl 5-alkyl-2-methyloxazole-4-carboxylate by dehydrobromination, but no reaction occurred with primary amines. While treatment of t-butyl 2-acetylimino-3,3-dibromoalkanoate with hydroxylamine or several aliphatic and aromatic primary amines gave addition products, t-butyl 2-acetylamino-3,3-dibromo-2-(hydroxyamino)- and 2-(substituted amino)alkanoate, respectively, in fairly good yields.
  • Toshio Fuchigami, Keijiro Odo
    1977 Volume 50 Issue 7 Pages 1793-1796
    Published: 1977
    Released: April 19, 2006
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    N-Chlorobenzamidine (1) reacted readily with dimethyl sulfide to form N-benzimidoylaminodimethylsulfonium chloride (2). Treatment of 2 with sodium hydroxide gave N-benzimidoyl-S,S-dimethylsulfilimine (3) quantitatively. The thermolysis of acyl derivatives of 3 gave rise to 1,2,4-oxadiazoles. N-Chloro derivative (6) prepared by treating 2 with sodium hypochlorite, reacted with potassium thiocyanate to form N-(3-phenyl-1,2,4-thiadiazolyl-5-yl)-S,S-dimethylsulfilimine (7).
  • Taku Matsuo, Satoru Mihara
    1977 Volume 50 Issue 7 Pages 1797-1801
    Published: 1977
    Released: April 19, 2006
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    On the irradiation of dibromomaleic anhydride in the presence of benzo[b]thiophene, both photosubstitution and photocycloaddition are simultaneously induced. The ratio of the substituted product to the cycloadduct increased with solvent polarity, and the same Stern-Volmer plots were obtained with both of the reactions. Kinetic parameters, obtained under various concentrations of benzo[b]thiophene, indicate that the reactions proceed via a common triplet exciplex. The activation energy for the photosubstitution is higher than that for the cycloaddition by 1–2 kcal/mol, where the former reaction is considered to proceed via a more polar transition state than the latter.
  • Masako Sakuragi, Hirochika Sakuragi
    1977 Volume 50 Issue 7 Pages 1802-1806
    Published: 1977
    Released: April 19, 2006
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    Irradiation of 1,2-diphenylcyclobutene (1) and diethylamine in hexane with light of longer wavelengths than 300 nm affords N,N-diethyl-1,2-diphenylcyclobutanamine (2a), 1,2-diphenylcyclobutane (3), and 1,1′,2,2′-tetraphenylbicyclobutyl (4). Upon similar irradiation, 1 and morpholine afford N-(1,2-diphenylcyclobutyl)morpholine 3 and 4. A mechanism involving a charge-transfer complex is proposed on the basis of the observations that the amines quenched the olefin fluorescence at a rate close to the diffusion limit in hexane, and that when diethylamine-N-d was used as an additive the deuterium was retained in the methine groups of compounds 2a, 3, and 4.
  • Hiroaki Takagi, Masahiko Sisido, Yukio Imanishi, Toshinobu Higashimura
    1977 Volume 50 Issue 7 Pages 1807-1812
    Published: 1977
    Released: April 19, 2006
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    Polysarcosine having a terminal electron donating group (p-dimethylaminoanilide group) and a terminal electron accepting group (3,5-dinitrobenzoyl group) was synthesized. An ethanol solution of the polymer showed a distinct charge-transfer absorption band around 435 nm. With use of the extinction coefficient determined for the low-molecular-weight model compounds, the fraction of polymers forming an intrachain complex was evaluated to be about 0.08 for \barn=6 (\barn is the degree of polymerization of the polysarcosine chain). The fraction decreased with rise in temperature and increase in chain length. The fraction experimentally observed was considerably larger than that estimated from the Monte Carlo calculation on polysarcosine chain, indicating that the cyclic conformations are greatly stabilized by the intrachain charge-transfer interaction. Thermodynamic parameters were determined for the intrachain complex. The chain length dependence of the parameters in ethanol was the opposite of that obtained previously in a chloroform solution. The difference was explained in terms of the difference of the conformations of polysarcosine chain in chloroform and in ethanol solutions. This was evidenced by the NMR spectra recorded in the solvents.
  • Shosuke Ito, Yoshimasa Hirata
    1977 Volume 50 Issue 7 Pages 1813-1820
    Published: 1977
    Released: April 19, 2006
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    The structure and configuration of an antibiotic, ikarugamycin, have been established to be 1e on the basis of chemical reactions, especially of oxidative degradation. It is suggested that the as-hydrindacene skeleton arises biogenetically via an intramolecular Diels-Alder reaction.
  • Tatsuo Tanaka, Hiroaki Yamazaki, Masaki Ohta
    1977 Volume 50 Issue 7 Pages 1821-1823
    Published: 1977
    Released: April 19, 2006
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    1,4-Disubstituted 2,6-piperazinediones (1) are susceptible to oxidation at the methylene group in the piperazine ring, giving piperazinetetrone (4) on being treated with selenium dioxide in boiling dioxane. Treatment of 1,4-diphenyl-2,6-piperazinedione (1a) with either nitrobenzene or tosyl chloride and triethylamine in benzene gives cyclic dimer (9) of dehydrogenated 1a. Cycloadduct (10) is obtained in the presecne of N-phenylmaleimide. It seems that both 9 and 10 are formed via labile mesoionic intermediate (8). Piperazinedione (1a) reacted with tosyl chloride, pyridine, and benzoyl chloride to give mesoionic compound (11) having 3-benzoyl and 5-(p-tolylthio) groups.
  • Yuh-Pan Chen, Rolan Liu, Hon-Yen Hsu, Shosuke Yamamura, Yoshikazu Shiz ...
    1977 Volume 50 Issue 7 Pages 1824-1826
    Published: 1977
    Released: April 19, 2006
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    Two new lignans, kadsurin and kadsurarin, were isolated from Kadsura japonica Dunal, and their structures were established. The stereostructures of the schizandrin-type lignans including their conformations were elucidated by measurements of intramolecular nuclear Overhauser effects.
  • Takashi Yamada, Toshifumi Miyazawa, Shigeru Kuwata, Hiroshi Watanabe
    1977 Volume 50 Issue 7 Pages 1827-1830
    Published: 1977
    Released: April 19, 2006
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    As a model of bottromycin, the structure of which had been proposed by Nakamura et al., an iminohexapeptide, Z–Val–Val–ImPro–Gly–Phe–Phe–OMe, and its related iminopeptides were synthesized in good yields. These syntheses were achieved by the condensation of the imidates, Z–ImPro–OEt, Z–Val-ImPro–OEt·HCl, or Z–Val–Val–ImPro–OEt·HCl, with the peptide esters, Gly–Phe–OMe·HBr or Gly–Phe–Phe–OMe·HCl, in the presence of triethylamine. All of the resulting iminopeptides were isolated as the hydrobromide or the hydrochloride. The pKa values of these iminopeptide salts were measured to be 9.75–9.3 in methanol-water; they showed that the pKa rule of Nakamura et al. could not be applied in the cases of these iminopeptides.
  • Akira Takeda, K\={o}ichi Shinhama, Sadao Tsuboi
    1977 Volume 50 Issue 7 Pages 1831-1835
    Published: 1977
    Released: April 19, 2006
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    The treatment of methyl-substituted 1-chloro-2-oxo-1-cyclohexanecarboxylic esters (7ae) with anhydrous Na2CO3 in refluxing xylene gave the corresponding methyl-substituted 1-cyclopentene-1-carboxylic esters (1ae). Several intermediates important in the synthesis of natural products, such as 4,4-dimethyl-1-cyclopentene-1-carbaldehyde (9), 5-methyl-1-cyclopentene-1-carbaldehyde (12), α-(3-methyl-1-cyclopentenyl)propionic acid (16), and ethyl 2-methyl-3-oxo-1-cyclopentene-1-carboxylate (17), have been prepared starting from esters 1e, 1d, 1b, and 1a, respectively.
  • Shosuke Yamamura, J. A. Lamberton, Hazime Irikawa, Yasuaki Okumura, Ma ...
    1977 Volume 50 Issue 7 Pages 1836-1840
    Published: 1977
    Released: April 19, 2006
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    The isolation and structures of six new alkaloids [yuzurine, daphnigracine, daphnigraciline, oxodaphnigracine, oxodaphnigraciline, and epioxodaphnigraciline] are described. The structure of yuzurine, which has been elucidated by means of an X-ray crystallographic analysis of the corresponding methiodide, is in full agreement with its spectral data. The structures of the other five alkaloids, all of which were isolated from the plant Daphniphyllum gracile Gage collected in New Guinea, were deduced on the basis of an exhaustive comparison of their spectral data coupled with chemical evidences. Finally, a plausible biogenesis of these alkaloids with a new type of nitrogen heterocyclic skeleton is discussed.
  • Tetsuo Otsubo, Shigeyoshi Mizogami, Norihisa Osaka, Yoshiteru Sakata, ...
    1977 Volume 50 Issue 7 Pages 1841-1849
    Published: 1977
    Released: April 19, 2006
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    A series of multilayered paracyclofuranophanes and paracyclothiophenophanes were synthesized by crossbreeding Hofmann elimination method from mixed quaternary ammonium hydroxides. Their structures and conformations were elucidated by NMR analyses. In electronic spectra, paracyclothiophenophanes exhibited stronge transannular electronic interactions than paracyclofuranophanes whose absorption curves show unexpected resemblance to those of multilayered metaparacyclophanes. Paracyclofuranophanes and [2.2](2,5)furanophane underwent addition reaction with benzyne to give 1 : 1 and 1 : 2 adducts, respectively. Their structures and properties were also studied by spectral measurements.
  • Katsuharu Iinuma, Shinichi Kondo, Kenji Maeda, Hamao Umezawa
    1977 Volume 50 Issue 7 Pages 1850-1854
    Published: 1977
    Released: April 19, 2006
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    A component of the antibiotic minosaminomycin (1), (−)-1D-1-amino-1-deoxy-myo-inositol (4) was synthesized from D-inositol (3) by catalytic oxidation of an axial hydroxyl group followed by reduction of the ketoxime. Minobiosamine, 1D-1-amino-1-deoxy-4-O-(α-D-kasugaminyl)-myo-inositol (2), was synthesized from 2′,4′-di-N-acetylkasuganobiosamine (9) by a similar method, and separated from the two isomers of 2. The total synthesis of 1 was accomplished by coupling 2′,4′-di-N-benzyloxycarbonylminobiosamine (14) and Nα-[(S)-1-benzyloxycarbonyl-3-methylbutylcarbamoyl]enduracididine (15) followed by removal of the protective groups. Compound 14 was derived from 1,2′,4′-tri-N-benzyloxycarbonylminobiosamine through the formation of the cis-1,2-carbamate. A diastereomer of 1 was also synthesized using alloenduracididine.
  • Yozo Miura, Hidetsugu Asada, Masayoshi Kinoshita
    1977 Volume 50 Issue 7 Pages 1855-1857
    Published: 1977
    Released: April 19, 2006
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    It was found that N-(arylthio)-t-butylaminyls (2) are easily generated by the photolysis of N-t-butylbenzene-sulfenamides (1). The ESR spectra of 2 were split into a 1 : 1 : 1 triplet by the interaction with the nitrogen nucleus (11.70–11.89 G), and each of the triplet was further split by the ring protons (ao-H: 0.89–1.07 G). The g-values of 2 lie in the range from 2.0068–2.0073. The radicals persist in benzene and it appears that they are not sensitive to the atmospheric oxygen.
  • Tetsuo Otsubo, Shigeyoshi Mizogami, Norihisa Osaka, Yoshiteru Sakata, ...
    1977 Volume 50 Issue 7 Pages 1858-1862
    Published: 1977
    Released: April 19, 2006
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    Several [2.2]naphthaleno- and [2.2]anthraceno-heterophanes were synthesized by cross-breeding Hofmann degradation of the corresponding two quaternary ammonium hydroxides. Two isomers, anti- and syn-forms, were obtained for [2.2](1,4)naphthaleno(2,5)thiophenophane, and one isomer, anti-from, for the [2.2](1,4)anthraceno homologue. The structures of the heterophanes were determined by variable temperature NMR analysis. Transannular π-electronic interactions between the condensed aromatic ring and the heteroaromatic ring were examined on the basis of electronic and emission spectra. The thiophene ring interacts more strongly with the condensed aromatic ring than the furan ring. For anthracenophanes, 9,10-bridged system shows more effective interaction than 1,4-bridged one.
  • Kazuhiko Saigo, Masahiro Usui, Kazunori Kikuchi, Eiichiro Shimada, Ter ...
    1977 Volume 50 Issue 7 Pages 1863-1866
    Published: 1977
    Released: April 19, 2006
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    Various carboxylic esters including functionalized ones are prepared in good yields from equimolar amounts of free carboxylic acids and alcohols under mild conditions by the use of 2-chloro- or 2-bromopyridinium salt, a new and efficient coupling reagent.
  • Seiichiro Ogawa, Shuichi Oki, Hideo Kunitomo, Tetsuo Suami
    1977 Volume 50 Issue 7 Pages 1867-1871
    Published: 1977
    Released: April 19, 2006
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    Isopropylidenation of 1,2-O-cyclohexylidene-myo-inositol and its 3-O-tosyl- and 3-O-benzoyl derivatives with 2,2-dimethoxypropane in N,N-dimethylformamide in the presence of acid catalyst gave the corresponding 4,5- and 5,6-O-isopropylidene derivatives. Selective benzoylation of 1,2-O-cyclohexylidene-4,5-O-isopropylidene-myo-inositol with benzoyl chloride in pyridine gave mainly the 3-O-benzoate, whereas with benzoic anhydride the 6-O-benzoate. Several unaccessible blocked inositols were prepared by displacement reaction of the protected sulfonyl derivatives with sodium benzoate.
  • Kinko Koyano, Hiroshi Suzuki, Colin R. McArthur
    1977 Volume 50 Issue 7 Pages 1872-1877
    Published: 1977
    Released: April 19, 2006
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    Rotational isomerization about the amide C–N bond of twelve N-alkyl-N-benzylcarbamoyl chlorides (C6H5CHX–NR–COCl, 1: X=H, 2: X=Cl; R=CH3, C2H5, n- and i-C3H7, n- and t-C4H9) was studied by proton NMR spectroscopy. The values of ΔG\ eweq for the isomerization are 15.8–17.3 kcal/mol for compounds 1 and 13.3–15.9 kcal/mol for compounds 2. Another kind of slow rotation was observed about the benzyl–nitrogen bond of 1(R=t-C4H9) and the α-chlorobenzyl–nitrogen bond of 2(R=CH3) at low temperature. The chiral centers of compounds 2 produce large nonequivalences for the geminal protons of the 2-methylene group of 2(R=n-C3H7) as well as 2(R=n-C4H9) and for the geminal methyl protons of 2(R=i-C3H7), reflecting some conformational preference of these compounds.
  • Akira Kasahara, Taeko Izumi, Mitsugi Maemura
    1977 Volume 50 Issue 7 Pages 1878-1880
    Published: 1977
    Released: April 19, 2006
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    2-Pyridylferrocene reacts with lithium tetrachloropalladate(II) in the presence of sodium acetate to give an ortho-palladated binuclear complex (4). The σ-bonded structure of 4 was confirmed by studies of the IR and NMR spectra and of the reactions of 4 with thallium (I) acetylacetonate and lithium aluminum deuteride. The reactions of 4 with carbon monoxide, butyllithium, and bromine were also examined.
  • Yasukatsu Tamai, Toshiaki Matsunaga, Kazutomi Suzuki
    1977 Volume 50 Issue 7 Pages 1881-1882
    Published: 1977
    Released: April 19, 2006
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    The contamination rates of the clean surfaces of metallic oxides by liquid-paraffin vapor are largely reduced by the coexisting water vapor. They are related to the hydrophilicity of oxides evaluated as the water-solid interaction free energy by the two-liquid-contact-angle method.
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