Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 59 , Issue 10
Showing 1-50 articles out of 82 articles from the selected issue
  • Yoshifumi Koide, Yasuyuki Eda, Kimiho Yamada
    1986 Volume 59 Issue 10 Pages 2963-2968
    Published: 1986
    Released: June 27, 2006
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    The polymerization of 2,6-xylenol (XOH) was catalyzed by using a copper complex of a telomer-type surfactant containing 4-vinylpyridine, 1-benzyl-4-vinylpyridinium chloride, and methyl acrylate or styrene (L-VP-Q, L-VP-Q-MA, L-VP-St, and L-VP-Q-St). A copper complex of L2.5VP3.9Q2.2MA catalyzed an emulsion polymerization of XOH more than that of L-VP-Q, 4-vinylpyridine polymer (VP-Q), or pyridine. Furthermore, the oxidative polymerization of XOH in several organic solvents was more effective than emulsion polymerization. The copper complexes formed reversed-micelles in water (3–10 vol%)-DMSO, and the catalytic actions were in the following order: L-VP-Q>VP-Q>pyridine. The acceleration by the L-VP-Q complex was considered to be due to the adsorption of XOH on reversed micelles.
  • Michio Yokozeki, Kazuo Shimokoshi, Eizo Miyazaki
    1986 Volume 59 Issue 10 Pages 2969-2971
    Published: 1986
    Released: June 27, 2006
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    The gaseous hydrogenation of methyl levulinate on the Ni surface modified with the optically active tartaric, malic and lactic acids was studied. It was found that γ-valerolactone is formed on an unmodified surface, while optically active methyl 4-hydroxypentanoate [MHP] and γ-valelolactone [VL] are formed consecutively on modified surfaces. Using these results and the temperature dependency of the reaction rates, along with previous theoretical results [J. Phys. Chem., 89, 2397 (1985)], it was concluded that, on an Ni surface modified with preadsorbed optically active acids, there are two different and independently operative sites, i.e., noninteractive (nonselective) and interactive (selective) sites which give the enantioselectivity. Further, the fractions of the noninteractive sites in the total amount of active sites were estimated to be about 18 and 13% for TA- and MA-modified surfaces respectively. A similar character of the active sites was found for the enantioselective hydrogenation of methyl acetoacetate [MAA] to methyl 3-hydroxybutyrate [MHB] on TA-modified Ni, where the fraction of noninteractive sites was evaluated to be about 15%.
  • Hiroshi Miyamoto, Hiroko Iijima, Masako Sugawara
    1986 Volume 59 Issue 10 Pages 2973-2978
    Published: 1986
    Released: June 27, 2006
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    The solubilities of lanthanoid iodates in dimethyl sulfoxide (DMSO)–water mixtures at 25 °C were measured. Thirteen lanthanoid iodate dihydrates Ln(IO3)3·2H2O (Ln=Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) were used. From the measured solubilities, the Gibbs free energies of the transfer of the iodates from water into aqueous DMSO solutions were calculated. The tetrad effect behavior reported by Peppard et al. was observed in both the variation with the lanthanoid atomic number of the solubility data and that with the atomic number of the free energies of transfer. The tetrad effect behavior seems to depend on a change in the solvation of the lanthanoid ions in variation with the crystal radii of the trivalent lanthanoid ions. In each system the logarithm of the solubility of the iodates decreases almost linearly with the reciprocal of the dielectric constant of the mixtures, as is expected from the Born equation or its modification when dealing with mixtures with narrow dielectric constant, ranging between 78.5 and 78.0.
  • Sanyo Hamai
    1986 Volume 59 Issue 10 Pages 2979-2982
    Published: 1986
    Released: June 27, 2006
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    The effects of α-, β-, and γ-cyclodextrin (CD) on intramolecular excimer formation between the two phenyl groups of diphenyl phosphate (DP) in aqueous solution were investigated by means of absorption and fluorescence spectra. It was found that DP forms 1 : 1 inclusion compounds with α-, β-, and γ-CDs. In the inclusion compound with α- or β-CD, only one phenyl group of a DP molecule is incorporated in the cavity of a CD molecule. In the case of γ-CD, however, the cavity can accommodate either one or two phenyl groups of a DP molecule. The pH dependence of the equilibrium constant for the formation of the inclusion compound between DP and β-CD has also been examined. Over the pH range from 3.46 to ≈10 the equilibrium constant does not change, whereas for pH values above ≈11 it decreases drastically.
  • Kazuo Sugiyama, Hiroshi Miura, Yasushi Nakano, Hideyuki Sekiwa, Tsuneo ...
    1986 Volume 59 Issue 10 Pages 2983-2989
    Published: 1986
    Released: June 27, 2006
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    The liquid-phase hydration of acrylonitrile has been examined over various single metal oxide catalysts at 65 °C. Numerous metal oxides have proved to be active for hydration and have been used to produce three products: acrylamide, ethylene cyanohydrin, and bis(2-cyanoethyl) ether. These oxide catalysts could be divided into two groups with respect to the acrylamide selectivity with 100% or not. A good relationship between the catalytic abilities (activity and selectivity) and the solid acid-base properties of each metal oxide group examined in benzene or in water was observed. Differences in the hydration selectivity to either a C≡N or a C=C bond of acrylonitrile over the catalysts could be explained on the basis of the IR spectra of two adsorbed states of acrylonitrile on the metal oxide surface. It was proved that the liquid-phase hydration of acrylonitrile over the insoluble metal oxide catalysts was an acid-base-catalyzed reaction proceeding on the acidic or basic surface hydroxyl groups.
  • Kazuro Kawamura, Shiushichi Kimura
    1986 Volume 59 Issue 10 Pages 2991-2996
    Published: 1986
    Released: June 27, 2006
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    ESR studies were carried out on a variety of glass-like carbons made from different precursors heat-treated in the range 300–2500 °C. It was found that the behaviors of unpaired electrons were nearly identical. The temperature dependence of ESR spectrum showed that the behavior of localized unpaired electrons in the glass-like carbons changed to that of delocalized ones at HTT about 2500 °C. The ESR spectrum of the glass-like carbons heat-treated at 800 °C consisted of a single line under a pressure of above 10−4 Torr but split into two components when air was admitted. This strong interaction with unpaired electrons and air (oxygen molecules) is caused by the active structure related to micropores in the glass-like carbons. We suppose that the polyene type radicals are the most suitable as the active structure to interpret the behavior of unpaired electrons in glass-like carbons heat-treated at 800 °C. As another major point in this study, it was found that there is a correlation between unpaired electron concentration and the g value.
  • Yoshimi Ozono, Yoshinori Nibu, Hiroko Shimada, Ryoichi Shimada
    1986 Volume 59 Issue 10 Pages 2997-3001
    Published: 1986
    Released: June 27, 2006
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    The polarized Raman and infrared spectra of [1H4]- and [2H4]pyridazines were studied. Assignments of the normal vibrations made by previous workers were reexamined on the basis of polarization behavior of the Raman and infrared bands and also through the normal coordinate calculation, and reasonable assignments are presented.
  • Yuko Hasegawa, Hirofumi Miyata, Satoshi Yoshida
    1986 Volume 59 Issue 10 Pages 3003-3006
    Published: 1986
    Released: June 27, 2006
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    The solvent extraction of copper(II) and zinc(II) with 12-crown-4 (12C4) or 15-crown-5 (15C5) as picrates into chloroform containing tributyl phosphate (TBP) has been studied. The following conclusions have been reached. i) Even in the presence of TBP which is more basic than crown ether, either copper(II) or zinc(II) is extracted in association with 2 moles of 12C4 or 15C5. ii) The crown ether complex of either copper(II) or zinc(II) forms 1 : 1 : 1 (metal(II): crown ether: TBP) stoichiometric adducts in chloroform. iii) The 12C4 complex of either copper(II) or zinc(II) forms more stable adducts with TBP than the 15C5 complex. iv) The extraction of the metal (II) with 15C5 and TBP is better than that of 12C4 and TBP. v) The copper(II) complex with 12C4 or 15C5 forms more stable TBP adducts than those from zinc(II) complex.
  • Masayuki Nakagaki, Hiroaki Komatsu, Hiromi Tanaka, Tetsurou Handa
    1986 Volume 59 Issue 10 Pages 3007-3012
    Published: 1986
    Released: June 27, 2006
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    The photoinduced reduction of Methyl Viologen (MV2+) by ethylenediaminetetraacetate (EDTA), 1,2-propanediamine-N,N,N′,N′-tetraacetate (MeEDTA), and trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetate (CyDTA) was investigated by using 3,3′-dioctadecylthiacarbocyanine (C18–18+) as a sensitizer in a micellar solution of a nonionic surfactant, heptaethylene glycol monododecyl ether. The production rate of reduced Methyl Viologen (MV) decreased with the light-irradiation time, while the deceleration increased in the order of: CyDTA<MeEDTA<EDTA. The concentration of the EDTA derivatives at the micellar surface was estimated to be in the order of EDTA<MeEDTA<CyDTA, this difference in the concentration being attributed to such hydrophobic groups as methyl group and cyclohexane ring in the EDTA-derivative molecules. The high concentration of the EDTA derivatives at the surface accelerated the reaction of the sensitizer divalent cation radical (C18–182+·) with the EDTA derivatives, prevented the consumption of MV through the back reaction of C18–182+· with MV, and facilitated the efficient photoproduction of MV. It was demonstrated that the hydrophobic interaction between the EDTA-derivative molecules and the micellar surface is an important factor in determining the efficiency of the photoinduced MV production.
  • Nobuaki Kambe, Takashi Tsukamoto, Noritaka Miyoshi, Shinji Murai, Nobo ...
    1986 Volume 59 Issue 10 Pages 3013-3018
    Published: 1986
    Released: June 27, 2006
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    Treatment of α,α′-dihalo-o-xylenes with sodium benzenetellurolate gave o-quinodimethane which readily reacted with dienophiles leading to Diels–Alder adducts. The best yields were obtained when the reaction was carried out in refluxing ethanol using two molar equivalents of the benzenetellurolate to α,α′-dihalo-o-xylenes. This reaction competes with substitution of the halogen atoms with the benzenetellurolate anion to afford α,α′-bis(phenyltelluro)-o-xylene, which did not give o-quinodimethane under identical conditions. It is likely that the reaction proceeds through nucleophilic attack of benzenetellurolate anion at the tellurium atom of α-halo-α′-phenyltelluro-o-xylene which is formed in situ by the substitution of one of the halogen atoms of the starting α,α′-dihalo-o-xylene with the benzenetellurolate anion. When sodium benzeneselenolate was employed, no evidence of o-quinodimethane formation was observed under similar conditions.
  • Kenjiro Meguro, Toshikazu Yabe, Sayuri Ishioka, Kazufumi Kato, Kunio E ...
    1986 Volume 59 Issue 10 Pages 3019-3021
    Published: 1986
    Released: June 27, 2006
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    The polymerization of styrene adsolubilized in a surfactant-adsorbed bilayer formed on the surface of inorganic pigments (iron oxide, titanium dioxide) was attempted in order to modify their surface properties. After the polymerization, the amount of polystyrene formed on the pigments gradually increased with an increase in the amount of styrene adsolubilized. Further, the molecular weight of the polystyrene formed changed with an increase in the amount of styrene. The surface properties of pigments after the polymerization were characterized by FTIR-PAS, turbidity, and zeta potential measurements.
  • Yoh Sano, Masayuki Nakagaki
    1986 Volume 59 Issue 10 Pages 3023-3028
    Published: 1986
    Released: June 27, 2006
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    Using the light-scattering theory of Rayleigh–Gans for spheroids, theoretical expressions were derived for the polarization state of light scattered by randomly oriented small and colored spheroidal particles in the case of linearly polarized incident light with an angle of inclination of ψ to the scattering plane. The azimuth angle ζ of the ellipse of the scattered light did not depend on the axial ratio p and the relative complex refractive index m (=m0−ik0), but was a function of only the scattering angle θ and ψ; also, the ellipticity of the ellipse of the scattered light was always equal to 0 and the scattered light was partially linearly polarized for linearly polarized incident light. The degree of polarization of the scattered light for spheroidal particles, P, defined as the ratio of the polarized component to the intensity of the scattered light, depended strongly on p, m0, k0, and θ together with the angle ψ. This P was found to be smaller than 1. In the case of spherical particles, P was always equal to 1 at any θ; this means that the scattered light was perfectly polarized. It has been concluded that a determination of P as a function of ψ and θ gives good information regarding the shape and the optical constants (m0 and k0) of the colored spheroidal particles.
  • Takeo Yamaguchi, Akira Yamauchi, Eiji Kimoto, Hideo Kimizuka
    1986 Volume 59 Issue 10 Pages 3029-3032
    Published: 1986
    Released: June 27, 2006
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    The ESR spectra of spin-labeled sodium dodecyl sulfate were examined by changing the concentration, temperature, and ionic strength. The broadening of ESR lines due to a monomer surfactant could be explained in terms of an electron-spin exchange and a monomer-micelle exchange. The spin-exchange rate increased with increasing temperature and decreased with increasing ionic strength, i.e., the spin-exchange frequency was closely related to the viscosity of the medium. On the basis of an analysis of the line width above the critical micelle concentration, it was found that the aggregation number of the micelle of this compound and the monomer-micelle exchange frequency were dependent on the ionic strength.
  • Yohko Sakamoto, Shosuke Watanabe
    1986 Volume 59 Issue 10 Pages 3033-3038
    Published: 1986
    Released: June 27, 2006
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    The relationship between chemical structure and carcinogenicity was investigated in thirty-eight polycyclic aromatic compounds and forty-four chlorinated aromatic hydrocarbons by means of 13C NMR. As an “index” serving as a measure of the electronic structure of aromatic compounds, which is closely related to the carcinogenicity, the averaged 13C NMR chemical shift over all the aromatic carbons in the molecule was used. In polycyclic aromatic compounds, the averaged chemical shifts of the carcinogenic compounds are within the range from 127.11 to 127.87 ppm, but those of the noncarcinogenic compounds are not within this range. In chlorinated monocyclic aromatic compounds, the carcinogenic compounds was within the range from 127.76 to 132.64 ppm. Thus, we proposed that the “index” is very useful for the discernment of the carcinogenicity of polycyclic and chlorinated monocyclic aromatic compounds.
  • Yoshifumi Tanimoto, Etsuko Shimada, Michiya Itoh
    1986 Volume 59 Issue 10 Pages 3039-3041
    Published: 1986
    Released: June 27, 2006
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    The magnetic field effects on hydrogen abstraction reaction of anthrone have been studied in micellar solution by laser flash photolysis and two-step laser excitation (TSLE) fluorescence. The decaytime of the anthrone ketyl radical determined by laser flash photolysis increases from 370 ns at zero field to 890 ns at 80 mT. The results are in accordance with the magnetic field effects on the risetime of the cage product by the TSLE fluorescence. All of the results are discussed in terms of the radical pair model.
  • Osamu Kikuchi, Ken-ichi Matsushita, Kenji Morihashi, Mitsunobu Nakayam ...
    1986 Volume 59 Issue 10 Pages 3043-3046
    Published: 1986
    Released: June 27, 2006
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    The conformation of 9,9′-bifluorenylidene and the EZ isomerization of its derivatives were examined by a two-configuration SCF calculation with the MINDO/3 approximation. The twisted conformation was calculated to be more stable than the folded one. The EZ isomerization occurs between two twisted conformers and the 90°-twisted structure is the transition state. The structural dependence of the rotational barrier of the isomerization is discussed.
  • Kisaburo Umemoto, Nobuyuki Okamura
    1986 Volume 59 Issue 10 Pages 3047-3052
    Published: 1986
    Released: June 27, 2006
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    In dimethyl sulfoxide, the reaction of hydroxide ion with several electron acceptors—iodine, tetracyanoquinodimethan, Nitro Blue Tetrazolium chloride, 2,3,5-triphenyltetrazolium chloride, anthraquinone, and benzophenone—gave reaction products identical to those obtained by the reaction of these electron acceptors with electron donors. The reaction pathways of these electron acceptors were found to be composed of successive one-electron reactions similar to the electrochemical reduction of these electron acceptors. These results indicate that hydroxide ion acts as a reductant in dimethyl sulfoxide.
  • Yoshihisa Yamamoto
    1986 Volume 59 Issue 10 Pages 3053-3056
    Published: 1986
    Released: June 27, 2006
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    Reactions of (C6H5)3P=CH2 (L) with TeCl4 of mole ratios 2 : 1 and 3 : 1 yield new compounds: dichlorobis(methylenetriphenylphosphorane)tellurium dichloride, [L2TeCl2]Cl2 (1), and chlorotris(methylenetriphenylphosphorane)tellurium trichloride, [L3TeCl]Cl3 (2), respectively. The reaction of ylide L with compound 1 yields a new compound: tetrakis(methylenetriphenylphosphorane)tellurium tetrachloride, [L4Te]Cl4 (3). The structure of compounds 13 is a distorted tetrahedron. The color of 13 is yellow. The electronic absorption spectra of compounds 2 and 2 show six absorption bands in the region 200–500 nm in dry dichloromethane. The reactions of ylide L with (C6H5)2SeCl2 of mole ratios 1 : 1 and 2 : 1 yield new compounds: chloro(methylenetriphenylphosphorane)diphenylselenium chloride, [LSe(Cl)(C6H5)2]Cl (9), and bis(methylenetriphenylphosphorane)diphenylselenium dichloride, [L2Se(C6H5)2]Cl2 (11), respectively. The color of the selenium compounds is white. The tellurium and selenium compounds are thermally stable in the solid state.
  • Yasuyuki Miura, Tomozo Koh
    1986 Volume 59 Issue 10 Pages 3057-3061
    Published: 1986
    Released: June 27, 2006
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    A method has been developed for the determination of micro amounts of pentathionate. It is based on the reaction of pentathionate with a given amount of permanganate in a dilute sulfuric acid medium and on the spectrophotometric measurement of iodine as triiodide, which is formed by the oxidation of iodide with an excess of permanganate. The analytical conditions were established by varying the temperature, reaction time, and amounts of sulfuric acid and permanganate. The present method can be successfully applied to a determination of pentathionate in the range 2×10−7 to 1.4×10−5 mol dm−3 (0.5–35.9 μg S5O62− in 10 cm3) and gives a higher sensitivity than any previous method without solvent extraction. In eleven determinations for 10 cm3 sample solutions containing 0.080 μmol of pentathionate, the present method gave a mean value of 0.0 with a standard deviation of 0.0006 μmol and a relative standard deviation of 0.75%.
  • Masumi Ushio, Yoshihiro Sumiyoshi
    1986 Volume 59 Issue 10 Pages 3063-3066
    Published: 1986
    Released: June 27, 2006
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    The appearance and disappearance of the crystal faces of the ZrSiO4 single crystal during crystal growth under the conditions of a growth temperature of 900 °C and a Δt value (temperature difference) of 1 °C have been studied by means of the Na2O·3V2O5 flux method. A spherical seed prepared from a natural zircon single crystal was used. The c{001}, a{100}, and m{110} appeared at the earliest stage, and next appeared r{115}, u{015}, p{111}, e{011}, and q{021} after 20 h of growth time. However, the u-face, r-face, and q-face disappeared after 400 h, and the c-face and a-face began to disappear after 500 h. The final morphology after 1400 h was a firstorder prism and a pyramid consisting of only the m-face and the p-face. It was found that the m-face and the p-face were dominant on a flux-grown ZrSiO4 single crystal, and that this tendency was unchangeable after 2500 h.
  • Kensei Kobayashi, Shinya Hashimoto, Koichi Iwase, Akira Otsuki, Kitao ...
    1986 Volume 59 Issue 10 Pages 3067-3072
    Published: 1986
    Released: June 27, 2006
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    Alkaline phosphatase activity in Lake Kasumigaura was determined periodically and characterized by highperformance liquid chromatography and isoelectric focusing electrophoresis. There are two peaks in dissolved alkaline phosphatase activity; the bigger one in summer and the smaller one in winter. Molecular weight of ca. 89000 and isoelectric points 5–6 were found for most phosphatases in samples collected during the summer. A considerable part of the winter alkaline phosphatases, however, have much higher molecular weights, and major isoelectric points for these were ca. 4. These alkaline phosphatases were metalloenzymes activated by zinc. The observations above suggest that there are seasonal changes in the dominant microbial species producing dissolved alkaline phosphatase; i.e., blue-green algae, a procaryote, in summer and diatoms and flagellates, eucaryotes, in winter. The peak of alkaline phosphatase activity in lake water was predictive of a following increase in algal species therein.
  • Katsuma Hiraki, Yoshio Fuchita, Motoharu Nakashima, Hirofumi Hiraki
    1986 Volume 59 Issue 10 Pages 3073-3077
    Published: 1986
    Released: June 27, 2006
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    2-t-Butylbenzothiazole reacts with palladium(II) acetate in acetic acid to produce the cyclopalladated dimer [{Pd(CH2CMe2–C7H4NS)(μ-MeCO2)}2] (2) (C7H4NS=2-benzothiazolyl). Complex 2 shows temperature-dependent 1H NMR spectra, which have been interpreted on the basis of the inversion motion of the acetato bridges. Metatheses of 2 with lithium chloride and sodium iodide result in the formation of the chloro- and iodo-bridged analogues, [{Pd(CH2CMe2–C7H4NS)(μ-Cl)}2] (3) and [{Pd(CH2CMe2–C7H4NS)(μ-I)}2] (4), respectively, each of which is found to be composed of cis and trans isomers. The 1H NMR spectra of 3 and 4 depend on temperature and are ascribed to rapid exchange between the two isomers. Equimolar amounts of 3 and 4 afford a μ-chloro-μ-iodo binuclear complex, [(C7H4NS–CMe2CH2)Pd(μ-Cl)(μ-I)Pd(CH2CMe2–C7H4NS)]. The reaction of 3 with thallium(I) acetylacetonate [Tl(acac)] produces a mononuclear cyclopalladated complex [Pd(CH2CMe2–C7H4NS)(acac)]. Complexes 2 and 3 react with CO in methanol to give MeO2CCH2CMe2–C7H4NS, the formation of which comfirms also the cyclopalladated structure of 2-t-butylbenzothiazole in 2 and 3.
  • Satoru Onaka, Tadashi Sugawara, Yuzo Kawada, Yukihiro Yokoyama, Hiizu ...
    1986 Volume 59 Issue 10 Pages 3079-3084
    Published: 1986
    Released: June 27, 2006
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    17O NMR spectra were measured for a series of manganese carbonyl derivatives, (CH3)xCl3−xSn–Mn(CO)5−yLy and (CH3)3−xSn[Mn(CO)5−yLy]x+1(L=P(OPh)3). 17O chemical shifts were correlated with carbonyl stretching frequencies, 119Sn-Mössbauer isomer shifts, and 55Mn NMR chemical shifts. From these correlations, 17O chemical shifts were interpreted in terms of σ- and π-electron acceptance of the tin moieties. It was also clarified that 17O NMR spectroscopy is a direct method to study electronic nature around the oxygen atoms in metal cluster compounds such as Me2Sn[Mn(CO)5]2 and MeSn[Mn(CO)5]3. 55Mn NMR spectra were also measured for some of these compounds to corroborate the 17O NMR results.
  • Makoto Yanaga, Taichi Miura, Kazutoyo Endo, Hiromichi Nakahara, Masuo ...
    1986 Volume 59 Issue 10 Pages 3085-3089
    Published: 1986
    Released: June 27, 2006
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    The 121Sb Mössbauer spectroscopic and the 1H and 13C NMR nuclear magnetic resonance studies have been performed for a series of organoantimony(V) compounds: R3SbX2 (R=CH3, C6H5, p-CH3C6H4; X=F, Cl, Br, I). For the trimethylantimony dihalides, the isomer shifts and quadrupole coupling constants of the 121Sb Mössbauer spectra indicated that the withdrawal of the bonding electrons from the antimony atom along Sb–X increased, as the electronegativity of the halogen increased. The chemical shifts of the 1H and 13C NMR spectra showed that the electron population around the methyl group increased with increasing electronegativity of halogen. For phenyl and p-tolyl derivatives, both 121Sb Mössbauer and 13C NMR data showed a trend similar to the methyl compounds. The results suggest that the electron cloud around the antimony atom spreads, with an increase in the electronegativity of the halogen, not only toward the halogen atoms but also toward the plane perpendicular to the bonding direction with the halogen atoms.
  • Mitsutomo Tsuhako, Chiyoko Sueyoshi, Tohru Miyajima, Shigeru Ohashi, H ...
    1986 Volume 59 Issue 10 Pages 3091-3095
    Published: 1986
    Released: June 27, 2006
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    The reaction of cyclo-triphosphate(P3m) with mono-(MEA), di-(DEA), or triethanolamine(TEA) in an aqueous solution was investigated under various conditions (mixing ratio of MEA, DEA, or TEA to P3m, pH, temperature, and reaction time). 1) In the pH region of 7–12, P3m reacted with MEA or DEA to yield tri-, di-, and monophosphate derivatives of MEA or DEA. The phosphoric acid ester of MEA or DEA was not formed at all. 2) The reactivities of MEA and DEA to P3m were in the order of MEA>DEA, and TEA did not react with P3m. 3) The reactivity of P3m with MEA or DEA decreased with the decrease in the pH, and no reaction took place under acidic conditions. 4) The maximum yields of triphosphate derivatives of MEA, N-(2-hydroxyethyl)triphosphoramidate(P3-(N)MEA) and of DEA, N-bis(2-hydroxyethyl)triphosphoramidate (P3-(N)DEA), were about 75 and 60% respectively at a molar ratio of 1 : 1, at pH 12, and at room temperature. 5) P3-(N)MEA and P3-(N)DEA easily recyclized to the raw material, P3m, under acidic conditions. 6) The mechanism of the reaction between P3m and MEA or DEA was investigated.
  • Takanobu Kumamoto, Kumiko Hosoya, Satoshi Kanzaki, Kazuhiro Masuko, Mi ...
    1986 Volume 59 Issue 10 Pages 3097-3101
    Published: 1986
    Released: June 27, 2006
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    It was found that the Birch reduction of 2-(2-thienyl)alkanoic acid and subsequent alkylation with benzyl bromide resulted in the formation of 2-alkyl-3-benzylthio-3-hexenoic acid selectively. Further, the Birch reduction of a 2,3-dialkylthiophene and subsequent alkylation with benzyl bromide gave a tetrasubstituted olefin which was formed by a selective C–S bond fission between the 1 and 5 positions of the thiophene nuclei. In contrast to these results, the Birch reduction of 3-thiophenecarboxylic acid derivatives and subsequent benzylation gave 2-alkyl-4-benzylthio-3-butenoic acid which was formed by a C–S bond fission between the 1 and 2 positions of the thiophene nuclei.
  • Takashi Matsumoto, Sachihiko Imai, Takashi Yoshinari, Shigeo Matsuno
    1986 Volume 59 Issue 10 Pages 3103-3108
    Published: 1986
    Released: June 27, 2006
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    The conversion of racemic α-cyclocitral into 3-(3-isopropyl-4-methoxyphenethyl)-4,4-dimethyl-2-methylenecyclohexanone (2) was carried out in five steps via 3-(3-isopropyl-4-methoxyphenethyl)-2,4,4-trimethyl-1-cyclohexene. An intramolecular cyclization of 2 with polyphosphoric acid produced the corresponding two tricyclic ketones possessing cis- and trans-A/B ring junctions. Each of these ketones was further converted into 12-mesyloxy-9(10→20)-abeo-abieta-1(10),8,11,13-tetraene in four steps. The mesylate was reduced with lithium aluminium hydride to give (±)-pisiferin.
  • Akihiko Ueno, Fumio Moriwaki, Tetsuo Osa, Tsukasa Ikeda, Fujio Toda, K ...
    1986 Volume 59 Issue 10 Pages 3109-3112
    Published: 1986
    Released: June 27, 2006
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    Catalytic activity of γ-cyclodextrin bearing an imidazole moiety (1) was compared with that of the corresponding β-cyclodextrin derivative (2) in the hydrolysis of p-nitrophenyl acetate. The catalysts 1 and 2 hydrolyzed the ester 80 and 172 times, respectively, as fast in the complexes as the buffer without any catalyst. The binding of 1 for the ester was 40% weaker than that of 2. When sodium 1-naphthaleneacetate was present in the catalytic systems, the hydrolysis rate was enhanced for 1, but depressed for 2. This rate enhancement of 1 suggests that sodium 1-naphthaleneacetate acts as a spacer which facilitates 1 to bind the substrate by narrowing the large γ-cyclodextrin cavity. The time dependency of p-nitrophenol formation under the conditions of large excess of p-nitrophenyl acetate to 1 or 2 exhibited that the inhibitory effect of the product was remarkable for 2, but negligible for 1.
  • Kazuo Mukai, Yoshiko Watanabe, Yuichi Uemoto, Kazuhiko Ishizu
    1986 Volume 59 Issue 10 Pages 3113-3116
    Published: 1986
    Released: June 27, 2006
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    It was observed by ESR measurement that the oxidation of α-, β-, γ-, and δ-tocopherols (vitamin E) with a stable phenoxyl radical in benzene immediately gives corresponding tocopheroxyl radicals. The rates of reaction of α-, β-, γ-, and δ-tocopherols with the stable phenoxyl radical in ethanol solution have been determined spectrophotometrically using stopped-flow technique, as a model reaction of tocopherols with unstable free radicals (ROO·, RO·, and HO·) in biological systems. The second-order rate constants obtained are (5.12±0.36)×103 (α-Toc), (2.24±0.04)×103 (β-Toc), (2.42±0.16)×103 (γ-Toc), and (0.51±0.01)×103 (δ-Toc), M−1 s−1 in ethanol at 25.0 °C. The relative rates agree well with those obtained from studies of the reactivities of tocopherols toward poly(styrylperoxyl) and galvinoxyl radicals by O2 consumption and by ESR method, respectively. The results suggest that the relative reactivities, that is, relative antioxidant activities of tocopherols do not depend on the kinds of unstable free radicals reacted.
  • Hiroshi Awano, Waichiro Tagaki
    1986 Volume 59 Issue 10 Pages 3117-3123
    Published: 1986
    Released: June 27, 2006
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    Mechanism of carboxylic acid-catalyzed reduction of substituted nitrosobenzenes by 1-benzyl-3,5-bis(1-pyrrolidinylcarbonyl)-1,4-dihydropyridine has been studied in acetonitrile at 25 °C. The major product was hydroxylamine when the dihydropyridine was used in excess over nitrosobenzene, while that was azoxybenzene in the reverse case. The observed second-order rate constant k2R are dependent on acid concentration in a first-order manner with the acid-catalyzed third-order rate constant kHR. The Hammett relationship for kHR for substituted nitrosobenzenes gave a ρ=−0.93. The Brönsted plot of log kHR vs. pKa of acids gave a straight line with a slope of −0.34. The deuterium isotope effect for the catalysis by dichloroacetic acid was found to be kHRkDR=2.80. These results indicate that a general acid catalysis by carboxylic acids plays an important role in the reduction of nitrosobenzene by dihydropyridine in acetonitrile.
  • Kazuhisa Abe, Kohichi Ito, Hiroko Suezawa, Minoru Hirota, Motohiro Nis ...
    1986 Volume 59 Issue 10 Pages 3125-3130
    Published: 1986
    Released: June 27, 2006
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    Conformations of a series of acyclic alcohols (CH3CH(R)CH(OH)CH3, CH3CH(R)CH(OH)CH(R′)CH3, and CH3CH(R)CH(OH)But) were studied (1) by measuring vicinal H–H coupling constants (3JH–H), (2) by lanthanoid-induced shift (LIS) analysis, (3) by molecular mechanics calculations (MM2), and (4) by ab initio (STO-3G, 4-31G geometry optimization) calculations. In the case of conformationally flexible alcohol as exemplified by 2-butanol and 3-pentanol, population of conformers determined by the LIS method do not agree with those determined by the 3JH–H, MM2, and ab initio methods. The discrepancy comes from the fact that the LIS measurement gives the most stable conformation of the alcohol in the LSR-alcohol complex and not of the free alcohol. In some flexible molecules, the most stable conformer in the complex can be different from that of the free molecule. In general, the conformational equilibrium is shifted by coordination of the shift reagent to the conformer whose alkyl chain stretches opposite to the direction of the coordination site of the shift reagent.
  • Hironobu Hashimoto, Koichi Araki, Yoshihiro Saito, Manabu Kawa, Juji Y ...
    1986 Volume 59 Issue 10 Pages 3131-3136
    Published: 1986
    Released: June 27, 2006
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    2-Azido-2-deoxypentose derivatives having D-xylo and L-arabino configurations were prepared via azidonitration of 1,5-anhydro-2-deoxypent-1-enitols, that is, xylal and arabinal derivatives, respectively. The L-ribo isomer was prepared by substitution of 2-trifluoromethylsulfonyloxy and 2-(1-imidazolylsulfonyloxy) group with azide. The D-xylo isomer was converted into the corresponding D-ribo and D-lyxo isomers.
  • Koichi Araki, Manabu Kawa, Yoshihiro Saito, Hironobu Hashimoto, Juji Y ...
    1986 Volume 59 Issue 10 Pages 3137-3143
    Published: 1986
    Released: June 27, 2006
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    Synthetic intermediates for the aminopentose disaccharide moiety of glycocinnamoylspermidine were synthesized from D-xylose.
  • Yukito Murakami, Jun-ichi Kikuchi, Toshihiko Takaki
    1986 Volume 59 Issue 10 Pages 3145-3151
    Published: 1986
    Released: June 27, 2006
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    Fusogenic behavior of the single-walled vesicles formed with mixed or individual synthetic peptide lipids, N+C5Ala2Cn and (SO3)C5Ala2Cn (n=14,16), was investigated in the presence of various water-soluble polymers or a nonbilayer-forming lipid by means of electron microscopy, differential scanning calorimetry, and turbidity measurements. The following ionic polymers having opposite charges to the net surface charges of the vesicles immediately induced fusion via vesicle aggregation; heparin, chondroitin sulfate C, chondroitin, and potassium salt of poly(vinyl sulfate) for the cationic vesicles, and polybrene for the anionic ones. On the other hand, ionic polymers having electrostatic charges identical with the vesicular surface charges and nonionic ones, such as amylose, poly(vinyl alcohol), polyethylene glycol 20000, and polyethylene glycol 6000, induced neither fusion nor aggregation. A nonbilayer-forming lipid, QC5Ala2C14, incorporated into the N+C5Ala2Cn vesicles induced fusion at kinetic rates much slower than those triggered by the ionic polymers. The observations were discussed with attention to the dehydration effect and the participation of nonbilayer structures in the fusion process.
  • Hiroshi Yonemura, Hiroshi Nishino, Kazu Kurosawa
    1986 Volume 59 Issue 10 Pages 3153-3159
    Published: 1986
    Released: June 27, 2006
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    The reaction of 3-phenylpropenoic acids with manganese(III) acetate–Cl complex yielded 1,2,2-trichloro-1-phenylethanes, 1-acetoxy-2,2-dichloro-1-phenylethanes, and 2,2-dichloro-1-phenylethanols. (E)-2,3-Diphenylpropenoic acids gave 2,2-dichloro-1,2-diphenylethanones and 2-acetoxy-1,2-diphenylethanones. 3,3-Diphenylpropenoic acids yielded 2,2-dichloro-1,1-diphenylethenes, 1-acetoxy-2,2-dichloro-1,1-diphenylethanes, 2,2-dichloro-1,1-diphenyl-1-ethanols, and 2-hydroxy-2,2-diphenylethanal. Fluorenylideneacetic acid gave 9-chloro-9-(dichloromethyl)fluorene, 9-acetoxy-9-(dichloromethyl)fluorene, and 9-fluorenone. 1-Cyclohexenecarboxylic acid yielded 1,2-dichlorocyclohexanecarboxylic acid and 1-acetoxy-2-chlorocyclohexanecarboxylic acid. The reaction can be explained in terms of a free-radical mechanism involving manganese(III) acetate–Cl complexation, addition of Cl radical, decarboxylation, and the oxidation of chloroethenes which are the reaction intermediates.
  • Noriyuki Fujimoto, Hiroshi Nishino, Kazu Kurosawa
    1986 Volume 59 Issue 10 Pages 3161-3168
    Published: 1986
    Released: June 27, 2006
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    The reaction of methylmalonic acid with mono- and disubstituted olefins in the presence of manganese(III) acetate yielded 2-carboxy-2-methyl-4-butanolides in moderate to good yields. The reactions of bromomalonic acid and chloromalonic acid with a variety of olefins gave 2-halo-4-butanolides and/or 2-buten-4-olides. The reaction of ethyl hydrogen malonate with olefins in the presence of manganese(III) acetate yielded 2-ethoxycarbonyl-2-buten-4-olides, 2-ethoxycarbonyl-2-ethenyl-4-butanolide, 2,7-dioxaspiro[4.4]nonane-1,6-diones, 2-ethoxycarbonyl-4-butanolide, and ethyl 3-butenoate. These reactions can be accounted for in terms of a free-radical mechanism involving substituted dicarboxymethyl radicals.
  • Masanori Kobayashi, Masato Yoshida, Michio Kobayashi
    1986 Volume 59 Issue 10 Pages 3169-3173
    Published: 1986
    Released: June 27, 2006
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    A novel photochemical addition of a germyl radical to the olefinic double bond was discovered when benzyltriethylgermane or dibenzyldiethylgermane was irradiated with a medium-pressure mercury lamp in the presence of olefins.
  • Syun Egusa, Masahiko Sisido, Yukio Imanishi
    1986 Volume 59 Issue 10 Pages 3175-3178
    Published: 1986
    Released: June 27, 2006
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    Optically active 3-(9-anthryl)alanine was synthesized for the first time and its cyclic dipeptide, cyclo(D-9-anthrylalanine)2, was prepared. Conformation of the cyclic dipeptide in solution was investigated by means of 1H NMR, absorption, circular dichroism (CD), and fluorescence spectroscopy. The coupling parameter JNH-CαH, observed in the NMR spectra indicated a planar configuration for the 2,5-piperazinedione ring of the dipeptide. The cyclic dipeptide showed a moderately large exciton couplet in CD spectrum and a small splitting in the 1Bb absorption band, but no excimer emission in fluorescence spectrum. These spectroscopic data suggest an unfolded-unfolded conformation for the side chains of the cyclic dipeptide.
  • Mareyuki Takahashi, Etsuo Niki, Akira Kawakami, Akira Kumasaka, Yorihi ...
    1986 Volume 59 Issue 10 Pages 3179-3183
    Published: 1986
    Released: June 27, 2006
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    Various kinds of fatty acid esters of L-ascorbic acid were synthesized and their role as chain-breaking antioxidant was studied in the oxidation of methyl linoleate in homogeneous solution. Fatty acid esters of ascorbic acid at either 6- or both 5- and 6-positions were effective as antioxidant and suppressed the oxidation of methyl linoleate, whereas those having ester group at 2-position did not act as antioxidant. 5,6-Erythorbyl dipalmitate was also effective as an antioxidant. Ascorbic acid esters inhibited the oxidation cooperatively with α- and δ-tocopherols as observed for free ascorbic acid. The antioxidant activity was correlated with the reactivity toward galvinoxyl radical.
  • Takashi Sakai, Toshiki Nakamura, Katsuyoshi Fukuda, Eiichiro Amano, Ma ...
    1986 Volume 59 Issue 10 Pages 3185-3188
    Published: 1986
    Released: June 27, 2006
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    Reduction of ethyl 2-acetoxy-3-oxobutanoate (4a) with immobilized baker’s yeast in calcium alginate gel gave a 18 : 19 : 63 mixture of ethyl (2R,3S)- and (2S,3S)-2-acetoxy-3-hydroxybutanoates and ethyl (2S,3S)-2,3-dihydroxybutanoate each with >95% e.e. in 58% yield. A similar treatment of a 2-benzoyloxy analog of 4a afforded a 6 : 94 mixture of ethyl (2R,3S)- and (2S,3S)-2-benzoyloxy-3-hydroxybutanoates (>95% e.e.) in 70% yield. Their absolute configurations were determined by comparison with authentic (2R,3S)- and (2S,3S)-2,3-dihydroxybutanoic acids. Effects of the immobilization and the pH of culture solution on the product ratio are also discussed.
  • Sadatoshi Akabori, Sadao Sato, Takehiko Tokuda, Yoichi Habata, Kayoko ...
    1986 Volume 59 Issue 10 Pages 3189-3195
    Published: 1986
    Released: June 27, 2006
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    Polythia[n](1,1′)ruthenocenophanes were prepared by reaction of 1,1′-bis(2-chloroethylthio)ruthenocene with disodium alkanedithiolates in tetrahydrofuran/ethanol. The ruthenocenophanes efficiently formed 1 : 1 complexes with platinum and palladium dichlorides. X-Ray crystallography of complexes of the 1,4,7,10-tetrathia[n](1,1′)ruthenocenophane with PtCl2 and PdCl2 revealed that the Pt (or Pd) atom bonded selectively to the two sulfur atoms at the 4,7-positions among the four sulfur atoms in the bridge of the ligand with a slightly distorted cis square-planar configuration. The conformation of the organic moiety in the 1 : 1 complex is greatly changed from that of the metal-free ligand. Also, the 1 : 1 palladium complex is isomorphous with the 1 : 1 platinum complex.
  • Toshikazu Ibata, Hiroyuki Nakawa, Yasushi Isogami, Kiyoshi Matsumoto
    1986 Volume 59 Issue 10 Pages 3197-3200
    Published: 1986
    Released: June 27, 2006
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    The high pressure Diels–Alder reactions of 5-methoxy-2-methyl-4-(p-nitrophenyl)oxazole with ethylenic dienophiles such as N-methylmaleimide, N-phenylmaleimide, dimethyl maleate and dimethyl fumarate gave the corresponding adducts in good to excellent yields. The effects of pressure, temperature, solvents on the yields were investigated. The high pressure also increased the formation of 3-hydroxypyridine derivatives via the elimination of methanol from the adducts. The stereospecificity of the reaction was confirmed for the reactions with maleate and fumarate.
  • Take-aki Mitsudo, Yoji Hori, Yoshihisa Watanabe
    1986 Volume 59 Issue 10 Pages 3201-3206
    Published: 1986
    Released: June 27, 2006
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    The reaction of terminal acetylenes with 1,3-butadienes catalyzed by (η4-1,5-cyclooctadiene)(η6-1,3,5-cyclooctatriene)ruthenium [Ru0(COD)(COT)]–PR3 (R=ethyl, butyl, octyl) in various solvents at 80 °C afforded linear codimers in good to excellent yield with high chemo-, regio-, and stereoselectivities. Reactions of deuterated acetylenes were also examined.
  • Masahiro Imoto, Shigeki Kageyama, Shoichi Kusumoto, Morihiro Kohno, Ke ...
    1986 Volume 59 Issue 10 Pages 3207-3212
    Published: 1986
    Released: June 27, 2006
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    6-Phosphate of N-acetylmuramyl-L-alanyl-D-isoglutamine and its lipophilic derivatives, i.e., 6-(octadecyl hydrogenphosphate) and 6-(2-docosyltetracosyl hydrogenphosphate) were synthesized after the structural feature of mycobacterial cell walls for the purpose to modify and possibly to enhance the immunostimulating activity of the muramyl dipeptide which is the minimum requisite for the activity. As expected, the latter more lipophilic phosphate showed a high activity in a tumor regression test.
  • Hiroyuki Nishide, Manshi Ohyanagi, Hiroyoshi Kawakami, Eishun Tsuchida
    1986 Volume 59 Issue 10 Pages 3213-3216
    Published: 1986
    Released: June 27, 2006
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    Molecular oxygen transport through a polymeric membrane was enhanced in the membrane of poly(octyl methacrylate-co-4-vinylpyridine), complexed with (N,N′-disalicylideneethylenediamine)cobalt(II), which forms an oxygen adduct rapidly and reversibly. The cobalt complex in the membrane effectively acted as a fixed carrier on oxygen permeation. The oxygen-binding parameters determined spectroscopically were adequate to analyze the dual-mode transport model.
  • Bharati Bhattacharjee, Manabendra Nath Bhattacharjee, Mitra Bhattachar ...
    1986 Volume 59 Issue 10 Pages 3217-3221
    Published: 1986
    Released: June 27, 2006
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    The kinetics of oxidation of substituted toluenes by pyridinium fluorochromate(VI) (PFC), C5H5N\overset+HCrO3F, in aqueous acetic acid, in the presence of perchloric acid, have been studied. The main products are the corresponding aldehydes. While each of the oxidation is first order with respect to the oxidant, the rate is almost independent of the substrate concentration. The reactions depend on the first power of the concentration of acid. A kinetic isotope effect, kHkD=5.4 at 30 °C, was observed. Electron-releasing groups were found to moderately facilitate the reaction, whereas the electron-withdrawing groups were found to have a retardation effect. Correlation with σ value yielded a ρ value of −2.0. The reaction does not induce polymerization of acrylonitrile. The effects of temperature and solvent compositions were studied and activation parameters evaluated. These and related data suggest that the initial reaction involves hydrogen abstraction forming an intermediate which subsequently produces the corresponding aldehyde.
  • Arun Kumar Kalkar, Comakshi C. Ars
    1986 Volume 59 Issue 10 Pages 3223-3228
    Published: 1986
    Released: June 27, 2006
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    Infrared and polarized laser Raman spectra in the solid phase and in the solution phase in different solvents have been obtained within the spectral region between 4000 and 200 cm−1 and analyzed for the purpose of vibrational assignments. The impact of intermolecular hydrogen bonding on amino group frequencies has been discussed in length. The fundamentals arising out of aromatic nucleus in particular various assignments are consistent with predicted spectral changes due to the presence of strong electron-activating amino group resulting in considerable perturbation of the vibrational levels of “parent” molecule pyrazine.
  • Chandrashekhar P. Vibhute, Shripad M. Khopkar
    1986 Volume 59 Issue 10 Pages 3229-3232
    Published: 1986
    Released: June 27, 2006
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    Germanium was quantitatively extracted with 0.1 mol dm−3 Aliquat 336S in xylene from 1×10−3 mol dm−3 citric acid solution adjusted to pH 3.5. It was stripped with 0.5 mol dm−3 hydrochloric acid and determined spectrophotometrically at 530 nm as the complex with phenylfluorone. It was effectively separated from binary as well as ternary mixtures by taking advantage of the difference in the stability of the citrate complexes with metal ions in mineral acids. The method was applied to the determination of germanium in coal fly ash.
  • Chinmay Chatterjee, Aya Singh Bali
    1986 Volume 59 Issue 10 Pages 3233-3237
    Published: 1986
    Released: June 27, 2006
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    Anation of pentaammineaquarhodium(III) ion by malonic acid, hydrogenmalonate, and malonate ions to form the hitherto unknown pentaamminemalonatorhodium(III) complex has been studied as a function of [H+] for the acidity range 1.4≤ pH ≤5.0, [total malonate], 0.3 mol dm−3 in the temperature range of 60 to 80 °C and at ionic strength 1.0 mol dm−3 adjusted with sodium perchlorate. Ion pairing is not significant between the complex and malonic acid but kinetically identifiable with hydrogenmalonate and malonate ions. Ion pair association constants for the hydrogenmalonate (Q1) and malonate ion (Q2) at 60 °C are 1.8 and 7.5 mol−1 dm3 respectively. The values of the rate constants at 60 °C for anation by malonic acid, hydrogenmalonate, and malonate ions are k0=3.04±0.2×10−5 mol−1 dm3 s−1, k1=1.73±0.2×10−4 s−1, and k2=3.46±0.4×10−4 s−1. The activation parameters, ΔH\ eweq and ΔS\ eweq corresponding to anation rate constants, k0, k1, and k2 are reported and the results discussed with reference to analogous reactions of Rh(III) and Co(III).
  • Rabindra Nath Mukherjee, Sanganabatla Shankar, Denis Louis Mascarenhas
    1986 Volume 59 Issue 10 Pages 3239-3242
    Published: 1986
    Released: June 27, 2006
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    The relative isotropic 1H NMR shifts of several pyridine-type base adducts of M(2,4-Me2dtpi)2 [where M=Co, Ni and 2,4-Me2dtpi=bis(2,4-dimethylphenyl)dithiophosphinate] were measured. The opposite signs of ring and methyl proton resonance shifts in α- and γ-picoline complexes of nickel indicate that both σ- and π-mechanisms are operative. In the cobalt cases all proton resonances are shifted down-field suggesting a negative dipolar contribution in addition to contact interaction. The magnetic and electronic spectral studies on these compounds are consistent with either MS4N or MS4N2 chromophores.
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