Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 55 , Issue 9
Showing 1-50 articles out of 78 articles from the selected issue
  • Hayao Kobayashi
    1982 Volume 55 Issue 9 Pages 2693-2696
    Published: 1982
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The thermal expansion coefficient, the electrical conductivity, and the crystal structure (at 325 K) of MEM(TCNQ)2 were examined. A new phase transition was observed at 315 K, where the thermal expansion coefficient jumps. This second-order transition may be triggered by the molecular motion of MEM cations and can be regarded as a precursor of the first-order transition around 62 °C. The molecular motion of MEM cations reduces the electrostatic lattice energy and leads to a structural change. The structural instability of TCNQ columns around 335 K is not attributable to the electron-electron correlation effect in the one-dimensional system, but to the change in the energy balance between the charge-transfer interaction and the electrostatic energy.
  • Katsumi Nakamaru
    1982 Volume 55 Issue 9 Pages 2697-2705
    Published: 1982
    Released: June 27, 2006
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    New five complexes of the type of [RuL3−x(dmby)x]X2(x=1,2,3, L=2,2′-bipyridyl or 1,10-phenanthroline, dmby=3,3′-dimethyl-2,2′-bipyridyl, X=halide ion) have been synthesized in order to investigate the effects of two methyl groups of dmby on the absorption and emission spectra, luminescence quantum yields, and lifetimes. Values of the radiative and nonradiative rate constants have been calculated from these data at 77 K. Although the absorption and emission maxima and the lifetimes are not much affected by the dmby ligand substitution, the molar extinction coefficients and emission quantum yields are decreased compared with trischelated complexes of the parent bipyridyl or phenanthroline ligands. At 25 °C the emission yields of the complexes containing dmby decrease by 3–4 orders of magnitude than at 77 K. Possible causes of the decrease in the quantum yields are discussed.
  • Yukio Kosaki, Akira Miyamoto, Yuichi Murakami
    1982 Volume 55 Issue 9 Pages 2706-2714
    Published: 1982
    Released: June 27, 2006
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    By using a three-way catalyst containing a metal oxide, CO is removed as CO2 even in the “rich” region of the air/fuel ratio. In order to elucidate the mechanism of this action of the added metal oxide, the reaction of CO with O2 on a Pt–V2O5/Al2O3 catalyst was investigated using a rectangular pulse-reaction apparatus. In the CO–O2 reaction on a Pt/Al2O3 catalyst, a significant amount of unreacted CO was exhausted in the “rich” region of the reactants. Furthermore, the conversion of CO decreased markedly with an increase in the CO/O2 ratio in the reactants. In the CO–O2 reaction on the Pt–V2O5/Al2O3 catalyst, on the other hand, the conversion of CO was high and did not decrease markedly with an increase in the CO/O2 ratio in the “rich” region. As for the reaction on the Pt–V2O5/Al2O3 at 558 K and above, the CO was completely removed as CO2 at any of the CO/O2 ratios examined. These effects of the added V2O5 were found to be due to: (i) the reaction of CO with an oxygen of V2O5 in the Pt–2O5/Al2O3 catalyst and (ii) the enhanced oxidation of CO with a gaseous O2 on the Pt/Al2O3 catalyst upon the addition of V2O5. On the basis of the kinetics of the oxidation of CO with the oxygen of V2O5 in the Pt–V2O5/Al2O3 and Pt black–V2O5 mixtures, its mechanism was proposed to be as follows; the oxygen of V2O5 at the Pt–V2O5 interface is activated by contact with Pt (this activated oxygen is denoted by [Pt···O···V]). The oxidation of CO with the oxygen of the Pt–V2O5/Al2O3 and Pt black–V2O5 mixtures proceeds according to the following two steps. Step I is the reaction of a gaseous CO with the active oxygen at the Pt–V2O5 interface, [Pt···O···V], to form CO2 and a reduced site, [Pt V]. Step II is the oxidation of the reduced site with the bulk oxygen in V2O5 to reproduce [Pt···O···V]. The enhanced oxidation of CO with a gaseous O2 caused by the addition of V2O5 to Pt/Al2O3 was found also to be understandable in terms of the active site, [Pt···O···V], where the reduced site, [Pt V], is oxidized by the gaseous O2 to reproduce [Pt···O···V] instead of the bulk oxygen in V2O5.
  • Hiroshi Morita, Józef S. Kwiatkowski, Anna Tempczyk
    1982 Volume 55 Issue 9 Pages 2715-2720
    Published: 1982
    Released: June 27, 2006
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    Electronic structures of the lactim and lactam forms of 2-, 3-, and 4-pyridinols, and of their anions and protonated cations were calculated by a modified CNDO-CI (mCNDO-CI), CNDO/S-CI, and a modified π-SCF-MO-CI methods. The theoretical results agree well with the observed spectra of both the neutral and ionic species, and predict satisfactorily the shorter wavelength shift of lower excited π-π* and n-π* bands of the lactim form compared to the corresponding bands of the lactam form. The π-π* assignment to the lowest triplet states of 2- and 4-pyridones, and of 2- and 3-pyridinols, together with the n-π* assignment to the lowest singlet state of 4-pyridone was predicted by the mCNDO-CI method, in agreement with the suggestion based on emission properties. The orbital energies calculated by the mCNDO method were compared with the observed photo-electron spectra; the results show that the fourth highest occupied orbital is π-orbital in 2- and 3-pyridinols, and σ-orbital in 4-pyridinol and 4-pyridone.
  • Sanyo Hamai
    1982 Volume 55 Issue 9 Pages 2721-2729
    Published: 1982
    Released: June 27, 2006
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    Inclusion compounds in the systems naphthalene–β-cyclodextrin (CDx) and 2-methoxynaphthalene (MN)–o-dicyanobenzene (DB)–β-cyclodextrin in aqueous solution were studied by means of absorption and fluorescence spectra. In the former system a naphthalene excimer fluorescence was observed. By the analyses of the concentration dependence of the absorption spectra and the excimer fluorescence intensities, the species responsible for the excimer fluorescence is identified as a 2:2 inclusion compound which is formed by association of two 1:1 naphthalene–CDx inclusion compounds, not a 2:1 inclusion compound in which two naphthalene molecules enter into the cavity of one CDx molecule. In the latter system, absorption and fluorescence spectra due to a charge transfer complex of MN with DB were observed. By analyses similar to the naphthalene case, the existence of a 1:1:2 association compound formed between a MN–CDx inclusion compound and a DB–CDx inclusion compound is confirmed. Fluorescence quenching by I and IO3 was also studied for the inclusion compounds in both systems.
  • Ei-ichiro Suzuki, Nobuya Nagashima
    1982 Volume 55 Issue 9 Pages 2730-2733
    Published: 1982
    Released: June 27, 2006
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    An automatic recording system was developed for unfrozen water content and spin-spin relaxation time measurements as continuous functions of temperature, by using a broad-line pulsed NMR spectrometer and a minicomputer. The advantages of this system are that the exact quantitative measurements can be done by calibrating the nonlinearity of the NMR sensitivity, and that for high sensitivity temperature measurement the thermocouple with special device is directly immersed in a sample. Three types of freezing-thawing hysteresis phenomena, (1) recrystallization of solute(hydroxy-L-proline, D-mannitol) and refreezing of released hydrated water molecules in frozen aqueous solutions, and (2) hysteresis as the characteristic feature of gels(gelatin, αsl-casein), and (3) supercooling of capillary water in water-insoluble materials(zein, yeast RNA, cellulose) were analysed. The usefulness of this system as an analytical instrument of hydration properties of biological materials is emphasized.
  • Midori Takimoto, Akio Takenaka, Yoshio Sasada
    1982 Volume 55 Issue 9 Pages 2734-2738
    Published: 1982
    Released: June 27, 2006
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    As a ternary interaction model between adenine:thymine base pair and carbamoyl group, 3-(adenin-9-yl)-propionamide: 1-methylthymine complex was prepared and its crystal structure was examined. The crystal exhibits a disordered structure, and the structure unit is a monoclinic cell with dimensions a=11.368(1), b=6.909(1), c=12.708(2) Å, and β=114.49(1)°. The space group is P21 and the unit cell contains two complexes and four water molecules. The base pairing pattern between adenine and thymine is the Hoogsteen type. The carbamoyl group is hydrogen-bonded to N(A1) of adenine in this base pair, the distance NH···N(A1) being 2.94(2) Å. With two kinds of hydrogen bonds of the carbamoyl group, NH···N(A1) above-mentioned and NH···O(carbamoyl), the 3-(adenin-9-yl)propionamide molecules form a sheet extending perpendicular to the c axis; the base-paired thymine molecules extrude alternately from the sheet. Diffused spots along c* with half integers of l can be interpreted as a stacking disorder of the sheets.
  • Kazuhiko Seki, Shinji Mori, Yoshio Imamura
    1982 Volume 55 Issue 9 Pages 2739-2743
    Published: 1982
    Released: June 27, 2006
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    From the point of view of the rotational isomeric state for the side groups (π- and o-conformation), the steric compression effect on the 13C chemical shift of the aliphatic carbons in poly(1-vinylnaphthalene)(P1VN) and poly(2-vinylnaphthalene)(P2VN) were evaluated according to H.J. Schneider’s method. In addition to the steric compression effect, the ring current effect by the naphthyl groups in P1VN and P2VN was taken into account. The numerical results suggested that the marked higher field shifts of the methine carbon of P1VN in comparison with that of P2VN, was attributed to the strong steric compression with the 1-naphthyl group (occupied the stable π-conformation) in the same monomer units. While in the P2VN chain, the resonances of the aliphatic carbons were calculated to be in the vicinity of those of polystyrene. Naphthyl ring current contribution to 13C-NMR chemical shifts was found to be small in comparison to the dominant steric compression effect.
  • Michio Yamanaka, Makoto Aratono, Hidemi Iyota, Kinsi Motomura, Ryohei ...
    1982 Volume 55 Issue 9 Pages 2744-2748
    Published: 1982
    Released: June 27, 2006
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    The adsorption behavior of dodecylammonium chloride (DAC) and sodium dodecyl sulfate (SDS) at their aqueous micellar solution/hexane interface has been studied by measuring the interfacial tension as a function of temperature at concentrations around the critical micelle concentration (cmc). The derivative of the interfacial tension with respect to temperature has been observed to change abruptly at the cmc and very little thereafter with increasing concentration in a limited range above the cmc. By applying the thermodynamic treatment of adsorption from micellar solution developed previously to the present experimental results, the entropy changes associated with the adsorption of DAC and SDS from monomeric state and from micellar state and the corresponding energy changes have been calculated. Further, the entropy and energy changes of micelle formation have been obtained from these quantity changes. These values have been compared with those obtained for DAC at water/air interface. It has been observed that the behavior of the micelle in the limited concentration range is controlled solely by temperature and pressure and bears resemblance to that of the adsorbed film at the interface. It has also been observed that the entropy and energy of micelle and adsorbed film are lowered by the hexane existing in the system.
  • Yuzo Yoshikuni, Arao Nakamura, Shigeo Shionoya
    1982 Volume 55 Issue 9 Pages 2749-2752
    Published: 1982
    Released: June 27, 2006
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    Photon echo decay time is measured for pentacence molecules introduced in naphthalene and p-terphenyl crystals with rather high concentrations (10−6–105 mol/mol) at temperatures between 1.6 K and 4.1 K, using a tunable picosecond laser system consisting of a mode-locked YAG laser and a parametric oscillator. In naphthalene echo decay time increases with lowering temperature approaching a constant value below 2 K, but in p-terphenyl it is almost constant. The phase relaxation time at very low temperature is much shorter than twice the population relaxation time in both crystals, indicating that pure dephasing processes exist. Analyzing the results it turns out that there exsists a pure dephasing process which is temperature-independent and is very probably due to interactions between pentacene molecules, in addition to the temperature-dependent dephasing process due to the scattering of pseudolocalized phonons.
  • Takeshi Ohno, Shunji Kato, Norman N. Lichtin
    1982 Volume 55 Issue 9 Pages 2753-2759
    Published: 1982
    Released: June 27, 2006
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    The mechanism of the quenching of the triplet state of zinc phthalocyanine (ZnPc) and Methylene Blue (MB+) by low-spin complexes of Fe(III) and Co(III) and aromatic oxidants was studied. The quenchers studied included FeIII(CN)63−, FeIII(CN)4(2,2-bipyridyl), FeIII(CN)2(2,2-bipyridyl)+, ferrocenium ion, CoIII(2,2′:6′-2″-terpyridyl)3+, CoIII(1,10-phenanthroline)3+, dimethylviologen, 1,4-benzoquinone, and 2,4,7-trinitro-9-fluorenone (TNF). The rate constants of the quenching of 3ZnPc varied from a diffusion-controlled one to 6×105 dm3 mol−1 s−1 in the mixed solvent of dimethylacetamide (DMA) and water (7:3 by volume). The metal complexes quenched 3MB+ and the triplet state of protonated MB+ with a rate constant of more than 2×106 dm3 mol−1 s−1 in an aqueous solution with 0.5 mol dm−3 of MgCl2. The fractions of electron transfer yielding ZnPc\underset.+ in the quenching process (F1) were high except for TNF and the iron(III) compounds. The F1 fractions were also obtained in the quenching of 3MB+ and the triplet state of the protonated MB+. The absence of radical production in the quenching by the doublet iron(III) compounds can be explained in terms of spin-allowed reverse electron transfer in the life of the geminate radical pair. Fractions of the reverse electron transfer between the half-reduced quencher and ZnPc\underset.+ or MB\underset.2+ were also measured; they are very close to those of 1–F1. The data reported in this study are consistent with the following mechanistic features. (1) Every quenching encounter produces a geminated radical pair. (2) The geminated pair is common to the quenching of the triplet excited state by oxidants and to the reverse electron transfer between the free radicals formed in the quenching. The molar extinction coefficient of ZnPc\underset.+ was determined to be 2.9×104 dm3 mol−1 cm−1 at 520 nm.
  • Osamu Shinji, Makoto Misono, Yukio Yoneda
    1982 Volume 55 Issue 9 Pages 2760-2764
    Published: 1982
    Released: June 27, 2006
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    The dehydrogenation of cyclohexane was studied by the use of a double tubular reactor; the inner tube was made of porous glass, and the outer tube, of non-porous glass. The Pt/Al2O3 catalyst was placed inside the inner tube. It was demonstrated that dehydrogenation proceeded beyond the equilibrium conversion to be expected in the absence of a porous tube, by separating the hydrogen produced from the central reaction zone through the porous tube. When the reaction rate was so high that the reactant gas reached equilibrium near the inlet of the reactor, the dehydrogenation conversion became greater (more than twice the equilibrium conversion) as the flow rate in the inner path decreased and the flow rate in the outer path increased. The experimental data obtained by using the porous reactor were well reproduced by a computer simulation based on a simple model, in which such parameters as the flow rate, the gas permeability, and the reaction rate, were considered. The potential application of the present porous-reactor system was also discussed.
  • Yoshimi Ishibashi, Ryoichi Shimada, Hiroko Shimada
    1982 Volume 55 Issue 9 Pages 2765-2770
    Published: 1982
    Released: June 27, 2006
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    The polarized Raman spectrum of the maleic anhydride single crystal was studied. Prominent polarization behavior of the Raman bands was observed. Assuming the oriented gas model, the relative intensities of the non-totally symmetric intramolecular vibrations in various polarized Raman spectra were studied based on the data of the crystal structure. The assignments of the fundamental vibrational frequencies for maleic anhydride were reinvestigated through the polarization behavior of the Raman bands as well as the normal coordinate calculation.
  • Fumio Kawaizumi, Hiroshi Suzuki, Hiroyasu Nomura, Yutaka Miyahara
    1982 Volume 55 Issue 9 Pages 2771-2778
    Published: 1982
    Released: June 27, 2006
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    A theory of electrostriction based on the spherical symmetry of electric field around ion and the dielectric continuum of solvent has been applied to the mixed solvent of water–methanol. The isothermal compressibility, κT, and the volume decrease, ΔV of primary solvation layer have been calculated for univalent ions. Calculation procedure consists of two steps; 1) calculation of the variation of electric field strength and dielectric constant with the distance from ion, 2) calculation of the compressibility and the volume decrease of electrostriction layer. In step 2), the calculation method proposed by Desnoyers et al. (J. Chem. Phys., 43, 243 (1965)) was used. Parameters necessary for the calculation were estimated in an appropriate manner and the results of calculation are shown as plots of κT and ΔV, vs. the distance from the center of ion. Partial molar volumes of LiCl, KCl, and CsCl in water–methanol system have been measured and the disordered part of partial molar volume has been determined after taking account of the values of κT and ΔV of the primary solvation layer.
  • Kunio Fukushima, Masahiro Yamaji
    1982 Volume 55 Issue 9 Pages 2779-2782
    Published: 1982
    Released: June 27, 2006
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    Raman spectra of pyridine in solvents of various hydrogen bonding powers were recorded and frequency shifts of some bands were measured. With methanol as solvent, Raman spectra recorded at temperatures between 128 and 293 K exhibit a remarkable change with temperature. Results are interpreted on the basis of possible existence of a σπ-complex.
  • Nobuaki Nakashima, Keitaro Yoshihara
    1982 Volume 55 Issue 9 Pages 2783-2787
    Published: 1982
    Released: June 27, 2006
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    Mist formation is observed when gaseous benzene (8–75 Torr) (1 Torr=133.322 Pa) with oxygen (\lesssim10−5–860 Torr) is irradiated by a KrF excimer laser. By measuring the falling speed, the size of droplets in the mist is determined to be 2 to 6 μm depending on gas pressure. The number of droplets produced by irradiation with a 100 mJ/cm2 pulse is estimated to be 1×105/cm3 by measuring the benzene pressure change and by turbidity measurement. The disappearance yield of benzene is 0.1 and phenol is identified with a quantum yield of 0.01. The nucleus is produced by two-photon excitation of benzene and allowed to grow into mist through a subsequent oxidation and/or polymerization reaction.
  • Norio Ohtomo, Kazuo Tokiwano, Kiyoshi Arakawa
    1982 Volume 55 Issue 9 Pages 2788-2795
    Published: 1982
    Released: June 27, 2006
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    The structure factors for heavy water at 25, 50, 70, and 95 °C were determined in the range of Q, 1.4–20 Å−1, by means of the time-of-flight (TOF) neutron diffraction method using the electron linear accelerator (LINAC). An analysis of the neutron diffraction data was made by applying a new general theoretical procedure of analysis for the fluid system composed of molecular clusters with various sizes. Structure factors were calculated according to the general procedure for the pentamer-monomer mixture model as a mixture of regular tetrahedral pentamers and non-bonded monomers with a due assignment of pentamer fraction at each temperature. Excellent agreement was obtained between the calculated and observed structure factors at temperatures in 25–95 °C. Combined with the preceding result (N. Ohtomo, K. Tokiwano, and K. Arakawa, Bull. Chem. Soc. Jpn., 54, 1802 (1981)), it was concluded that the pentamer-monomer mixture model is the best one for water from room temperature to near the boiling point.
  • Narishi Gonohe, Norio Yatsuda, Naohiko Mikami, Mitsuo Ito
    1982 Volume 55 Issue 9 Pages 2796-2802
    Published: 1982
    Released: June 27, 2006
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    The one-photon fluorescence excitation and two-photon resonant multiphoton ionization spectra of the S1←S0 transition of 1,4-diazabicyclo[2.2.2]octane (DABCO) in a supersonic free jet have been obtained and analyzed. It was found from the vibrational analysis that the S1←S0 transition is one-photon forbidden, two-photon allowed and the one-photon absorption appears by the vibronic interaction between the S1 and S2 states through the e′ vibrations. In addition, from the fluorescence spectrum and the polarization studies of the two-photon spectrum using the two linearly polarized laser beams of different wavelengths, it was concluded that the S1 state is 1A1. The sequence structure involving the low-frequency cage torsional vibration has been observed in the two-photon resonant multiphoton ionization spectra of DABCO and 1-azabicyclo[2.2.2]octane (ABCO). The potential functions with respect to the torsional motion for both ground and excited states have been determined by utilizing the observed vibrational levels. It was found that the torsional potential has a broad minimum near the D3h (for DABCO) and C3V (for ABCO) conformations.
  • Sadayasu Inagaki, Shigeo Murata, Minoru Sakiyama, Yoshikatsu Ito, Yasu ...
    1982 Volume 55 Issue 9 Pages 2803-2807
    Published: 1982
    Released: June 27, 2006
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    Standard energy of combustion and standard enthalpy of sublimation were determined for the title compounds with static bomb combustion calorimetry and with sublimation calorimetry, respectively. Derived standard enthalpies of combustion and of formation at 298.15 K were as follows: ΔH°c(c)=−(12354.3±1.8), ΔH°f(c)=−(304.6±3.4), and ΔH°f(g)=−(189±8) kJ mol−1, respectively, for 2,4,6-triisopropylbenzophenone(1), and ΔH°c(c)=−(12440.6±1.6), ΔH°f(c)=−(218.3±3.3), and ΔH°f(g)=−(101±10) kJ mol−1, respectively, for 3′,5′-diisopropyl-4,4-dimethyl-3-phenyl-1,2-benzocyclobuten-3-ol(2). The enthalpy change for the reaction: 1(g)→2(g), of 88 kJ mol−1, which may be supposed to be the magnitude of light energy stored in the latter molecule, has been discussed.
  • Sadayasu Inagaki, Shigeo Murata, Minoru Sakiyama
    1982 Volume 55 Issue 9 Pages 2808-2813
    Published: 1982
    Released: June 27, 2006
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    Standard energy of combustion at 298.15 K and standard enthalpy of sublimation as a function of temperature were determined for thioacetamide and tetramethylthiourea by oxygen bomb combustion calorimetry and sublimation calorimetry. Derived standard enthalpies of formation in crystalline and gaseous states at 298.15 K are −(70.6±1.1) and (12.7±1.2) kJ mol−1, respectively, for thioacetamide, and −(38.3±2.3) and (44.7±2.4) kJ mol−1, respectively, for tetramethylthiourea. Stabilization energies of these molecules were evaluated by estimating the standard enthalpies of formation in gaseous state for the hypothetical reference structures by use of the group contribution method.
  • Akira Shibata, Shinsuke Yamashita, Takuya Yamashita
    1982 Volume 55 Issue 9 Pages 2814-2819
    Published: 1982
    Released: June 27, 2006
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    The specific anion effects on water structure at the polypeptide monolayer–water interface were investigated. It was found that the effects of anions on increasing the film transition pressure were in the order of SCN>Br>Cl>F in line with that of those anions as breakers of water structure. The SCN ion disrupts the hydrophobic hydration surrounding the hydrocarbon moieties of polypeptides and lipids at the interface. On the other hand, the presence of F ion as a structure maker tends to stabilize the hydrophobic bonding. The increase of the film transition pressure on KSCN subsolution was associated with a difference in the conformation between poly(γ-benzyl L-glutamate) and poly(γ-benzyl DL-glutamate). The infrared spectra of polymers obtained from single and mixed films were practically identical with the collapsed films in the presence and the absence of SCN and F ions.
  • Kenkichiro Kobayashi, Yoshihiro Aikawa, Mitsunori Sukigara
    1982 Volume 55 Issue 9 Pages 2820-2826
    Published: 1982
    Released: June 27, 2006
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    Electron transfer theory at tunnel semiconductor electrode was derived from the double adiabatic perturbation theory. The cathodic current of Ce4+ with very positive redox potential was measured at highly doped SnO2 electrode. The rearrangement energy of 0.65 eV for Ce4+ was estimated from the relationship of transfer coefficient vs. electrode potential. Large electron transfer rate in the high overvoltage region can be explained in terms of the contribution of excited vibrational states in the first coordination sphere into electron transfer.
  • Susumu Okazaki, Hidekazu Touhara, Koichiro Nakanishi, Nobuatsu Watanab ...
    1982 Volume 55 Issue 9 Pages 2827-2830
    Published: 1982
    Released: June 27, 2006
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    Monte Carlo calculations have been carried out for pure water and aqueous solution of Lennard-Jones particle at infinite dilution between 273.15 K and 353.15 K in order to examine temperature effect on the hydrophobic hydration. It is found that internal energy of mixing ΔU due to the introduction of the solute into water becomes less negative monotonously with increasing temperature. It is in good correspondence with the tendency obtained from solubility measurement, and represents that heat capacity of mixing ΔCV is positive. Furthermore the dissolution proceeds no longer exothermically at 353.15 K, where water behaves as a normal solvent. Several structural and energetical distribution functions have been calculated for the deep understanding of these observations.
  • Kazuhiko Suga, Nobuyuki Nishi, Minoru Kinoshita
    1982 Volume 55 Issue 9 Pages 2831-2834
    Published: 1982
    Released: June 27, 2006
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    A new application of the T1←S0 excitation spectroscopy is presented by which absorptions to one or two of the three spin sublevels can be measured separately. This method has been applied to the T1←S0 excitation of crystalline 1,2,4,5-tetrachlorobenzene and 9H-xanthen-9-one at 1.4 K. The vibrational structures of the excitation spectra are analyzed in view of the spin selectivity observed.
  • Hiroatsu Matsuura, Hiromu Murata
    1982 Volume 55 Issue 9 Pages 2835-2839
    Published: 1982
    Released: June 27, 2006
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    Force field was systematically determined in terms of the group symmetry coordinates for series of CH3-(OCH2)mOCH3 (m=1–3), the polymer (–OCH2–)n, and their deuterated derivatives, and of CH3(SCH2)mSCH3, (–SCH2–)n, and their deuterated derivatives. Twenty-five force constants for the oxymethylene molecules and twenty-two force constants for the thiomethylene molecules were adjusted by using 178 and 126 observed wave-numbers, respectively. The force constants obtained were compared with those for related molecules. The results of the normal coordinate treatment on the polymers were discussed in comparison with the results in previous works.
  • Satoshi Kondo, Mamoru Shimoi, Akira Ouchi, Toshio Takeuchi
    1982 Volume 55 Issue 9 Pages 2840-2846
    Published: 1982
    Released: June 27, 2006
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    The crystal and molecular structure of the title complex has been determined by the X-ray diffraction method. The crystal was triclinic, space group P\bar1, a=12.80(1), b=16.65(1), c=8.659(9) Å, α=104.6(1), β=93.7(2), γ=107.5(1)°, Z=2, DX=1.892(3), Dm=1.91(2) Mg m−3, μ(Mo Kα)=3.45 mm−1, and the final R value was 0.051 for 3577 reflections. The coordination number of both neodymium atoms is nine, although the coordinated atoms around one neodymium atom are arrayed in a tri-capped trigonal prism, and those around the other neodymium atom, in a mono-capped tetragonal antiprism. The neodymium atoms are arrayed on a linear chain bridged by the ligand; however, no metal-metal interaction is observed. The corresponding complexes of cerium(III), praseodymium(III), and europium(III) form isomorphous crystals with the title complex, but the complex of lanthanum(III) has the formula of ML3·4.5H2O (HL=(methylthio)acetic acid), and the complexes of dysprosium(III) and ytterbium(III), ML3·2H2O.
  • Yutaka Taniguchi, Yoichi Shimura
    1982 Volume 55 Issue 9 Pages 2847-2850
    Published: 1982
    Released: June 27, 2006
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    A convenient method for the determination of CD spectra in multiple scattering systems is demonstrated. The formula of approximation, which gives the molar CD in terms of the values observable with commercial spectrometers by using a plate of opal glass, is presented based on some assumptions. The resulting solid-state CD spectrum of Λ-[Co(en)3]Br3·H2O is reported and compared with the solution CD spectrum.
  • Kin-ya Suzuki, Guee-deuk Park, Kunio Ohzeki, Tomihito Kambara
    1982 Volume 55 Issue 9 Pages 2851-2853
    Published: 1982
    Released: June 27, 2006
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    A simple and sensitive method for the determination of hexacyanoferrate(III) is described. This method is based on the preconcentration of hexacyanoferrate(III) ion on the coagulated material prepared from finely divided anion and cation exchange resins. The mixed resin is collected on a filter paper, forming a disk of thin layer. The hexacyanoferrate(III) fixed on the resin is converted to Turnbull’s Blue by treating with iron(II) ammonium sulfate solution. The colored compound in the resin phase is determined by a densitometer equipped with a linearizer. The working range is 0.4–3.0 μmol dm−3 hexacyanoferrate(III). Among cations likely to be present, only copper(II) interferes, however, the interference is removed by the addition of EDTA. Hexacyanoferrate(II) ion shows the same coloration as hexacyanoferrate(III), and the total amount is determined when both ions are present.
  • Ken-ichi Machida, Gin-ya Adachi, Jiro Shiokawa
    1982 Volume 55 Issue 9 Pages 2854-2857
    Published: 1982
    Released: June 27, 2006
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    The IR spectra for the high-pressure polymorphs of alkaline-earth metasilicates, viz. α-CaSiO3, δ-CaSiO3, α-SrSiO3, δ-SrSiO3, and δ′-SrSiO3, which consist of cyclic anions, (Si3O9)6− or (Si4O12)8− rings, were studied over a range of 1200–400 cm−1. These silicates gave absorption bands in wavenumbers of about 1050–820 cm−1, 750–620 cm−1, and below about 580 cm−1, based on symmetrical and anti-symmetrical stretches of Si–O bonds and Si–O bending modes for tetrahedral SiO4 units, and Ca–O or Sr–O stretches. Among them, the bands characteristic of the silicate anions with ring structure in the SrSiO3 polymorphs were found to shift to lower wavenumber with transformation into the δ′ form. This suggests that the (Si4O12)8− ring in δ′-SrSiO3 is less flexible than the (Si3O9)6− ring in the α or δ form. The experimental result that the quenching temperature of δ′-SrSiO3:Eu2+ phosphor is higher than that of the δ form supports this consideration.
  • Eiichi Miki, Masaaki Motonaga, Kunihiko Mizumachi, Tatsujiro Ishimori, ...
    1982 Volume 55 Issue 9 Pages 2858-2862
    Published: 1982
    Released: June 27, 2006
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    New nitrosyls, [Fe(C9H6NO)2(NO)]2(C9H6NO=8-quinolinolate ion), [Fe(C10H8NO)(NO)2] (C10H8NO=2-Methyl-8-quinolinolate ion), and [Fe(C9H5NOCl)2(NO)(DMF)] (C9H5NOCl=5-chloro-8-quinolinolate ion) were isolated by the reaction of nitrogen monoxide with a mixture of iron(II) perchlorate and the corresponding quinolinol in methanol or methanol/DMF. They were characterized by IR, 57Fe-Mössbauer, and magnetic measurements.
  • Youichi Demura, Kazuyoshi Hirakawa, Ichiro Murase
    1982 Volume 55 Issue 9 Pages 2863-2865
    Published: 1982
    Released: June 27, 2006
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    A copper(II) complex of 2,2′-bi-8-quinolinol was prepared. The structure has been determined by means of infrared and electronic spectra, magnetic susceptibility under temperature variation, and molecular weight measurement. It was found to be a binuclear chelate having a tetrahedral arrangement around each copper ion.
  • Kiyokatsu Watanabe
    1982 Volume 55 Issue 9 Pages 2866-2872
    Published: 1982
    Released: June 27, 2006
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    The following new cobalt(III) complexes containing the 8-amino-3,6-diazaoctanate ion (adao) have been isolated: two isomers of β-mer(N)-trans(Cl,Oada)-[Co(adao)(Cl)(NH3)]ClO4, two isomers of β-mer(N)-trans(Cl, Oadao)-[Co(adao)(Cl)(py)]ClO4, β-mer(N)-trans(O)-Co(adao)(H2O)(py)]ClO4·bcs, β-mer-(N)-trans(Cl,Oadao)-[Co(adao)(Cl)(H2O)]CLO4, β-fac(N)-[Co(adao)(Cl)(H2O)]ClO4, β-mer(N)-cis(O)-[Co(adao)(NO2)(H2O)]ClO4, and β-fac(N)-[Co(adao)(Cl)(NO2)]. The geometrical structures have been determined on the basis of the absorption spectra, the proton NMR spectra, and the consideration of their preparative processes.
  • Masakazu Kita, Kazuaki Yamanari, Yoichi Shimura
    1982 Volume 55 Issue 9 Pages 2873-2880
    Published: 1982
    Released: June 27, 2006
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    Twelve new mixed sulfenato and sulfinato cobalt(III) complexes were prepared via successive H2O2 oxidation of [Co(SCH2CH2NH2)3], [Co{SCH2CH(COOCH3)NH2}3], and related complexes. These oxidation products, [Co(sulfenato-N,S)n(sulfinato-N,S)3−n] (n=3, 2, 1, and 0), were optically resolved by means of column chromatography or preferential crystallization of a diastereomeric molecular compound with d-tartaric acid. The mixed sulfenato and sulfinato complexes show characteristic variation of absorption spectra with the change of “n” in [Co(sulfenato-N,S)n(sulfinato-N,S)3−n] (n=3, 2, 1, and 0). It is concluded that the (R) configuration of the sulfenato group is more stable than the (S) one in the fac(S)-Λ-[Co(sulfenato-N,S)n(sulfinato-N,S)3−n].
  • Isao Ando, Shigeyoshi Nishijima, Kikujiro Ujimoto, Hirondo Kurihara
    1982 Volume 55 Issue 9 Pages 2881-2885
    Published: 1982
    Released: June 27, 2006
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    The mono-complex formation of nickel(II) ion with 2,2′-bipyridine(bpy) and 1,10-phenanthroline (phen) was studied in aqueous solution by means of a stopped-flow method. The apparent complex formation rates of the Ni(II)–bpy and Ni(II)–phen complexes depended on the pH of the solution. The rate constants of the mono-complex formation with the ligand in the free base form, kf, and that with the monoprotonated ligand, kfh, were evaluated from the rate-[H+] profiles in the region of high hydrogen ion concentration where the pseudo-equilibrium of acid dissociation of the ligands was attained during the complex formation. The rate constants determined for the Ni(II)–phen were kf=(2.6±0.3)×103 mol−1 dm3 s−1 and kfh=2.4±0.3 mol−1 dm3 s−1, which are practically the same as those reported elsewhere. On the other hand, the rate constants for the Ni(II)–bpy were kf=(5.3±1.2)×103 mol−1 dm3 s−1 and kfh=5.0±2.6 mol−1 dm3 s−1, which are quite different from the values reported by other researchers. The validity of the present data was discussed in terms of slow proton-transfer reactions of the ligands.
  • Shunichi Fukuzumi, Nobuaki Nishizawa, Toshio Tanaka
    1982 Volume 55 Issue 9 Pages 2886-2891
    Published: 1982
    Released: June 27, 2006
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    The kinetics of the oxidative addition of iodine to the following isocyaniderhodium(I) monomers and dimers in MeCN has been examined; [Rh(RNC)4]+, [Rh(RNC)2(PPh3)2]+, [Rh2(dppm)2(RNC)4]2+, and [Rh2(dicp)4]2+ (R=alkyl, aryl; dppm=bis(diphenylphosphino)methane; dicp=1,3-diisocyanopropane). The reaction proceeds via two consecutive steps which consist of the formation of the initial adduct followed by the intramolecular isomerization to yield the final trans-adduct. The kinetic results for the first step of the oxidative addition reactions suggest that there exist three kinds of intermediates formed between the Rh(I) complex and iodine with 1:1, 1:2, and 2:1 stoichiometry prior to the formation of the initial adduct. This mechanism coincides with that for the electron transfer reactions between the Rh(I) complexes and inorganic oxidants such as [Fe(N-N)3]3+ (N-N=1,10-phenanthroline and 2,2′-bipyridine). The values of the rate constants for the first step of the oxidative addition of iodine to dppm- or dicp-bridged Rh(I) dimers are found to agree with those for the electron transfer reactions between the same reactants by using linear free energy relationships. The possibility of electron transfer activation as the rate determining step in the oxidative addition to Rh(I) complexes is discussed.
  • Shunichi Fukuzumi, Nobuaki Nishizawa, Toshio Tanaka
    1982 Volume 55 Issue 9 Pages 2892-2897
    Published: 1982
    Released: June 27, 2006
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    The cyclic voltammogram of a CH3CN solution of [Rh(p-MeOC6H4NC)4]+ exhibits three anodic current peaks which correspond to the oxidations of the monomer, the dimer, and the trimer, with no cathodic wave on the reverse scan. The anodic peak potentials Eoxp in such irreversible cyclic voltammograms were determined for various Rh(I) monomers and the oligomers such as [Rh(RNC)4]+, [Rh2(RNC)8]2+, [Rh2(dppm)2(RNC)4]2+, [Rh2(dicp)4]2+, [Rh3(RNC)12]3+, and [Rh4(dicp)8]4+ (R=p-MeOC6H4 and Ph, etc; dppm=bis(diphenylphosphino)methane, dicp=1,3-diisocyanopropane). The anodic peak potentials Eoxp vary mainly with the degree of oligomerization of the Rh(I) complexes, decreasing in the order monomer>dimer>trimer>tetramer, in parallel with the energies of the highest occupied molecular orbitals EHOMO. It has been found that the Eoxp values are linearly correlated with logarithm of the rate constants for the electron transfer reactions with inorganic oxidants such as [Fe(bpy)3]3+ and [Co(bpy)3]3+ (bpy=2,2′-bipyridine) in the context of the Marcus theory as expected when the standard oxidation potentials Eoxo would be used. It is thus suggested that the anodic peak potentials of the Rh(I) complexes in the irreversible system can be used as the standard oxidation potentials as far as the relative values are concerned.
  • Yukito Murakami, Yasuhiro Aoyama, Jun-ichi Kikuchi
    1982 Volume 55 Issue 9 Pages 2898-2901
    Published: 1982
    Released: June 27, 2006
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    As regards the effect of zinc(II) ion on the reduction of hexachloroacetone, the kinetic activity of a [20]paracyclophane (PCP) bearing 1,4-dihydronicotinamide (HNA) and 2-pyridinecarboxylic acid (Py) moieties, HNA–PCP–Py, has been investigated as an alcohol dehydrogenase model in reference to that of PCP–HNA in the light of their metal-coordination behavior. The reduction ability of PCP–HNA was significantly lowered as it underwent complex formation with zinc. On the other hand, HNA–PCP–Py showed an apparent rate maximum in a relatively lower concentration range of ZnCl2. The kinetic behavior was analyzed on the basis of the formation of two kinds of zinc complexes of HNA–PCP–Py: the 1:1 complex (Remark: Graphics omitted.), in which both Py and HNA moieties are simultaneously coordinated to the same zinc ion, showed a decreased reactivity relative to metal-free HNA–PCP–Py; while the 2:1 complex (HNA–PCP–Py–ZnII–Py–PCP–HNA), in which HNA is free from metal-coordination, exercised a much enhanced activity, 7 times as reactive as metal-free HNA–PCP–Py. A plausible reaction mechanism for the enhanced reactivity has been discussed.
  • Makoto Watanabe, John R. Van Wazer
    1982 Volume 55 Issue 9 Pages 2902-2905
    Published: 1982
    Released: June 27, 2006
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    A preferential exchange of chlorines and bridging oxygens between phosphorus(III and V) chlorides and diarsenic trioxide was studied by adding diarsenic trioxide into phosphorus chlorides and then heating the mixtures at 50–60 °C with vigorous stirring under dried nitrogen (phosphorus(III) chlorides) or dried air (phosphorus(V) chlorides). 31P NMR study showed that the exchange of chlorines and oxygens occurred between diarsenic trioxide and phosphorus trichloride, phosphoryl chloride, diethylphosphinic chloride, tetramethyl-phosphorodiamidic chloride, or diethylphosphinothioic chloride and that P–O–P bonds were formed in the products.
  • Akira Sugimori, Toshikazu Furihata, Shigeyuki Mikayama, Makiko Yoshida ...
    1982 Volume 55 Issue 9 Pages 2906-2910
    Published: 1982
    Released: June 27, 2006
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    The UV-irradiation of 2-pyridinecarbonitrile(1) in methanol and in ethanol brings about the replacement of the cyano group by the hydroxyalkyl groups and the replacement of the ring hydrogen by the alkoxyl group. Free base-form of 1 in ethanol undergoes exclusively photo-hydroxyethylation, while the pyridinium form of 1 in ethanol undergoes both photo-hydroxyethylation via a singlet excited state and -ethoxylation via a singlet-excited state complex, which is quenched by the electron transfer from the aromatic hydrocarbons to the excited complex.
  • Tetsuya Yamada, Yasuhiko Kondo, Shigekazu Kusabayashi
    1982 Volume 55 Issue 9 Pages 2911-2916
    Published: 1982
    Released: June 27, 2006
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    The reaction of 1-ethyl-3-methyl-4-imidazoline-2-thione with methyl iodide followed simple second order kinetics in polar solvents, whereas in less polar solvents the reverse process made a significant contribution to the overall rate. The solvent effects on the forward rate constant were linearly related to those on the rate of the reaction of tetramethylthiourea with methyl iodide. A plot of ΔV0\ eweq vs. Δ\barV° was linear with a slope of 0.33. From the volume changes and enthalpy changes measured, three transition state indices, (Δ2V\ eweqΔ2\barV°), nT and α were determined in acetonitrile, ca. 0.33, 0.32, and 0.41, respectively.
  • Mitsuji Yamashita, Koji Hiramatsu, Manabu Yamada, Nobuyoshi Suzuki, Sa ...
    1982 Volume 55 Issue 9 Pages 2917-2921
    Published: 1982
    Released: June 27, 2006
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    Diphenylphosphine and diphenylphosphinite derivatives of sugars such as methyl 6-deoxy-4-C-(diphenylphosphino)-2,3-O-isopropylidene-α-L-talopyranoside, methyl 4-O-(diphenylphosphino)-2,3-O-isopropylidene-α-L-rhamnopyranoside, methyl 4-C,4-O-(diphenylphosphino)-2,3-O-isopropylidene-α-L-talopyranoside, 6-deoxy-6-C-(diphenylphosphino)-1,2:3,5-di-O-isopropylidene-α-D-glucofuranose, and 6-O-(diphenylphosphino)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose were synthesized by the reaction of diphenylphosphine-sodium dihydrobis(2-methoxyethoxy)aluminate (SDMA) and/or diphenylphosphinous chloride-triethylamine with sugar derivatives. Homogeneous asymmetric hydrogenations of several prochiral olefins (α-acetylaminocinnamic acid, methyl α-acetylaminocinnamate, α-benzoylaminocinnamic acid, itaconic acid, and tiglic acid) were carried out using rhodium(I) catalysts with the tervalent chiral phosphorus derivatives of sugars. The highest optical yield for all the five substrates was obtained when di-μ-chloro-bis(cyclooctadiene)dirhodium(I) and 6-O-(diphenylphosphino)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose were used. The advantages of this method are the simplicity in the synthesis of the chiral phosphorus compound and the comparatively high optical yield in the asymmetric hydrogenation of olefins.
  • Tadashi Kozuka
    1982 Volume 55 Issue 9 Pages 2922-2927
    Published: 1982
    Released: June 27, 2006
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    Various azidoquinones were prepared from methyl 3-substituted 2,3-dihydro-5-hydroxy-6-methylbenzofuran-2-carboxylate. Irradiation of these azidoquinones gave methyl 3-substituted 6-methyl-4,7-dioxoindole-2-carboxylates, a model of mitomycin analogs, in a moderate yield.
  • Tokunaru Horie, Masao Tsukayama, Mitsuru Nakayama
    1982 Volume 55 Issue 9 Pages 2928-2932
    Published: 1982
    Released: June 27, 2006
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    Sudachiin A was isolated from the green peels of Citrus sudachi Hort. ex Shirai. This structure was deduced to be sudachitin 4′-β-D-glucoside by means of its spectra and degradation; this was confirmed by the synthesis of the one from sudachitin 7-benzyl ether and α-acetobromoglucose via several steps. 4′,5,7-Trihydroxy-3′,6,8-trimethoxyflavone 7-glucoside (sudachitin 7-β-D-glucoside), which was isolated from Sideritis leucantha Cavanilles, was also synthesized from sudachitin and α-acetobromoglucose in a similar manner.
  • Tokunaru Horie, Hiroki Kourai, Hideaki Osaka, Mitsuru Nakayama
    1982 Volume 55 Issue 9 Pages 2933-2936
    Published: 1982
    Released: June 27, 2006
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    5,6-Dihydroxy-3,4′,8-trimethoxyflavone, which was the proposed structure of the pigment occuring in Conyza stricta, was synthesized from 2,3,5,6-tetramethoxyacetophenone in six steps. The natural pigment was identical not with the synthesized flavone, but with 5,7-dihydroxy-3,4′,8-trimethoxyflavone, an isomer of the former.
  • Sei-ichi Nishimoto, Tsukuru Izukawa, Tsutomu Kagiya
    1982 Volume 55 Issue 9 Pages 2937-2941
    Published: 1982
    Released: June 27, 2006
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    The in-source photoreaction and the postreaction of 1-(2-naphthoyl)aziridine (NAz) in various halogenated hydrocarbons have been investigated at room temperature under deaerated conditions. Secondary amide such as N-(2-chloroethyl)-2-naphthamide (CENA) or N-(2-bromoethyl)-2-naphthamide (BENA) was obtained along with a rearranged product of 2-(2-naphthyl)-2-oxazoline (NOz). The initial rate of secondary amide formation increased with decreasing dissociation energy of the carbon–halogen bond of halogenated hydrocarbon. The yield of CENA in the postreaction was substantially equal to that of chloride ion formed via the photolyses of chlorinated hydrocarbons. The rearranged product of NOz was confirmed to undergo subsequently photochemical ring-opening reaction to afford CENA or BENA.
  • Toshihiro Seo, Toshio Kakurai
    1982 Volume 55 Issue 9 Pages 2942-2948
    Published: 1982
    Released: June 27, 2006
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    Copolymerizations of 2-amino-4-(substituted amino)-6-isopropenyl-1,3,5-triazines (methacryloguanamine) with alkyl methacrylates using redox initiator gave polymers with high molecular weights in satisfactory yields. The monomer reactivity ratios and Q-e values were also determined. Softening and glass transition temperatures rose and specific gravity increased with the increase in the content of triazine units. The copolymers were slightly soluble in nonpolar solvents and readily soluble in polar solvents with a solubility parameter (δ)=11–13. This polymer with aminotriazine groups showed high viscosity in acid solution and can be utillized as polyelectrolyte.
  • Tsujiaki Hata, Noboru Gokita, Nobuo Sakairi, Kazuo Yamaguchi, Mitsuo S ...
    1982 Volume 55 Issue 9 Pages 2949-2955
    Published: 1982
    Released: June 27, 2006
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    Trityl (Tr), 4-methoxytrityl (MMTr), and 4,4′-dimethoxytrityl (DMTr) groups were introduced into the 2-amino group of 2′,3′,5′-tri-O-acetylguanosine by treatment with the corresponding trityl chlorides in pyridine to afford the N2-tritylated guanosine derivatives in high yields. Similarly, the N6-tritylated adenosine derivatives were synthesized. The stability of the three kinds of trityl groups under acidic conditions were described. The MMTr and Tr groups were found to be suitable for the protection of the 2-amino group of guanosine in oligonucleotide synthesis. An appropriately protected N2-tritylguanosine 5 -phosphorodithioate derivative was synthesized and utilized for the synthesis of pGpUpU.
  • Nobuo Ishikawa, Kazuhiko Iwamoto, Tatsumi Ishiwata, Tomoya Kitazume
    1982 Volume 55 Issue 9 Pages 2956-2958
    Published: 1982
    Released: June 27, 2006
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    Reactions between alkanoyl chlorides and F-propene or F-chloroethene with fluoride ion were investigated. While alkyl (F-isopropyl) ketones and 1-(F-isopropyl)alkenol esters were formed in the former case, 1-(F-1-chloroethyl)alkenol esters were exclusively obtained in the latter case. Reaction mechanisms are discussed.
  • Kenzo Inoue, Teruo Matsuura, Isao Saito
    1982 Volume 55 Issue 9 Pages 2959-2964
    Published: 1982
    Released: June 27, 2006
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    Photosensitized oxidations of tryptophan (Trp), tryptamine, and their derivatives were investigated with a variety of sensitizers. Rose Bengal sensitized photooxidations proceed exclusively via Type II mechanism (singlet oxygen mechanism), whereas for thionine-sensitized photooxidations both Type I (nonsinglet oxygen mechanisms) and Type II mechanisms are operative under a given set of conditions. Rate constants of reaction, in units of 106 M−1 s−1, were determined to be 3 for Trp, 4 for tryptophan methyl ester, 4 for Nb-acetyltryptophan methyl ester, 9 for tryptamine, and 7 for Nb-methoxycarbonyltryptamine in the Rose Bengal-sensitized photooxidations. These values are in good agreement with those obtained from reactions with chemically generated singlet oxygen. Quenching rate constants are somewhat larger than reaction rates constants, indicating that the quenching process is the major path for the interaction of singlet oxygen with these indolic substrates. Oxidation products in chemically generated singlet-oxygen reaction of Trp are compared with those obtained from dye-sensitized photooxidations.
  • Kazuhiko Tanaka, Hideki Uneme, Shuichi Matsui, Aritsune Kaji
    1982 Volume 55 Issue 9 Pages 2965-2972
    Published: 1982
    Released: June 27, 2006
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    The reactions of a variety of 1,3-bis(phenylthio)propanes with butyllithium have been shown to produce cyclopropyl phenyl sulfides in good to high yields. A new and convenient in situ preparation of 1-lithiocyclopropyl phenyl sulfide can be readily carried out by treating 1,3-bis(phenylthio)propane with 2 equiv. of butyllithium at 0 °C in THF. The reaction with electrophiles proceeds in good yield. O-Aryl and O-alkyl S-cyclopropyl dithiocarbonates also can be prepared in good yields. 1,2-Bis(phenylthio)ethane was converted to phenyl vinyl sulfide on treatment with butyllithium, while 1,4-bis(phenylthio)butane was recovered unchanged by a similar treatment.
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