Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 54 , Issue 2
Showing 1-50 articles out of 73 articles from the selected issue
  • Naoto Yamamoto, Yoshikatsu Nagasawa, Sadanobu Shuto, Hiroshi Tsubomura
    1981 Volume 54 Issue 2 Pages 323-326
    Published: 1981
    Released: June 02, 2006
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    Titanium electrode surface was chemically modified with an aminosilane. The potential of the electrode was shifted to the negative direction by a reaction of fluorescein isothiocyanate in solution with the amine on the electrode surface. The absorption and emission spectra were measured for the fluorescein isothiocyanate, fixed by the reaction with the aminosilane which was chemically bound on the surfaces of tin oxide, titanium oxide and quartz, in solutions and in air. In an alkaline solution, the absorption and emission spectra showed the band ascribable to the dianion of the fluorescein. A peak, attributable to the monoanion, was observed in both absorption and emission spectra measured for the samples kept in air. The surface coverage of the dye was estimated from the absorbances to be about 10−6 mol m−2 for both tin oxide and quartz. The bound dye fluoresced under exposure to ultraviolet light, due probably to the energy transfer from tin oxide to the dye.
  • Takehiro Abe
    1981 Volume 54 Issue 2 Pages 327-334
    Published: 1981
    Released: June 02, 2006
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    A theoretical expression for the spectral solvent shifts of an anion has been presented by assuming the system to consist of a large anion, its counter cations, and numerous solvent molecules. In the zeroth-order all the component particles in the system do not interact with one another. The interaction energy among the particles for the ith-excited state of the system, in which only the anion is in the ith-excited state, is calculated by the second-order perturbation treatment as the sum of electrostatic interaction energies between pairs of particles. The expression derived from the difference between the interaction energies of the ground and excited states of the system contains the dipole-dipole and dipole-induced dipole interaction terms and the dispersion force terms and is somewhat different from the previous results for neutral solutes (Bull. Chem. Soc. Jpn., 38, 1314 (1965)). Effects of the counter cations are discussed. This expression is applied to the spectral shifts of an Eosin-Y2− anion, a Meisenheimer complex, and Janovsky complexes.
  • Shin-ichi Ishiguro, Hitoshi Ohtaki
    1981 Volume 54 Issue 2 Pages 335-342
    Published: 1981
    Released: June 02, 2006
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    The hydrolytic reactions of lead(II) ions were calorimetrically studied at 25 °C in an aqueous solution and dioxane-water mixtures (dioxane contents: 0.1 and 0.2 mole fractions, which correspond to 35.21 and 55.01 % w/w, respectively) both containing 3 mol dm−3 (Li)ClO4 as a constant ionic medium. A fully automatic on-line system was used for the calorimetric titrations. Values of enthalpies and entropies for the formation of the Pb3-(OH)33+, Pb4(OH)44+, Pb3(OH)42+ and Pb6(OH)84+ complexes in the aqueous solution, 0.1 and 0.2 mole fraction dioxane solutions were given. For the reaction qPb2++pH2O=Pbq(OH)p(2qp)++pH+, the values of ΔHpq*/kJ mol−1 and TΔSpq*/kJ mol−1 were determined as follows: Pb3(OH)33+ 66.6, −20.7 (in aqueous solution); 72.1, −13.4 (in 0.1 mole fraction dioxane solution); 66.9, −17.7 (in 0.2 mole fraction dioxane solution); Pb4(OH)44+: 81.4, −29.5;84.1,−22.1;94.7,−14.7; Pb3(OH)42+: 61.6, −68.4;83.4,−41.0,99.8,−24.3; Pb6(OH)84+:242.8, 1.3, 243.2, 10.6; 236.7, 2.0. The solvent effects on ΔHpq* were discussed in terms of a function of the formal charge per metal ion of the complex, z′=(2qp)⁄q. The thermodynamic parameters obtained for the Pb6(OH)84+ complex were better explained by assuming the reaction, 2Pb3(OH)42+=Pb6O(OH)64++H2O, than the reaction, 2Pb3-(OH)42+=Pb6(OH)84+, and thus the Pb6(OH)84+ complex formally written from the result of the potentiometric measurements will be described as Pb6O(OH)64+ which has previously been proposed by X-ray diffraction.
  • Takehiko Ono, Yoshiro Nakagawa, Yutaka Kubokawa
    1981 Volume 54 Issue 2 Pages 343-347
    Published: 1981
    Released: June 02, 2006
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    The rate of oxidation of C3H6, C2H4, C3H8, and CO has been investigated over V–Sn oxides of various compositions. The rate shows two maxima at V–Sn(V/Sn=2/1) and (1/8) oxides. Comparison between the rate of reduction of the oxides with C3H6 and that of the corresponding catalytic oxidation suggests that the oxygen species responsible for oxidation differs for V–Sn(2/1) and V–Sn(1/8) oxides. The amount of oxygen desorbed in the temperature range 400–530 °C varies with the composition of the V–Sn oxides, showing a maximum at V–Sn(2/1) oxide. With V–Sn(1/8) oxide, little or no oxygen desorption is observed. On the basis of these results together with those of structural studies, it is concluded that the rate maximum with V–Sn(2/1) oxide arises from formation of an amorphous material from which lattice oxygen is easily released, while the rate maximum with V–Sn(1/8) oxide is associated with the presence of V4+ ions dissolved in SnO2.
  • Kyuya Yakushi, Masaaki Iguchi, Gen Katagiri, Takahisa Kusaka, Toshiaki ...
    1981 Volume 54 Issue 2 Pages 348-357
    Published: 1981
    Released: June 02, 2006
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    The visible and near-infrared reflection spectra were measured, at temperatures in the range of 27–300 K, on the single crystals of (N-ethyl-1,10-phenanthrolinium)(TCNQ)2, (methyltriphenylphosphonium)(TCNQ)2 and Cs2(TCNQ)3. We found that the dispersion observed at about (10–11)×103 cm−1 in the reflection spectra of the former two salts is due to the local excitation associated with the lowest π-π transition of (TCNQ). A new dispersion attributable to intermolecular charge transfer was found to appear at (7–8)×103 cm−1 in the spectrum of (methyltriphenylphosphonium)(TCNQ)2, at low temperature. In the case of Cs2(TCNQ)3, the low-temperature spectrum showed that there are two dispersions in the range of (8–14)×103 cm−1, one of which being attributable to the charge transfer between (TCNQ) ions and the other to the local excitation associated with (TCNQ). We propose a new interpretation for the spectra of TCNQ complex salts on the basis of these new experimental data.
  • Ko-ichi Sugawara, Kiyoshi Okazaki, Shin Sato
    1981 Volume 54 Issue 2 Pages 358-361
    Published: 1981
    Released: June 02, 2006
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    The pulse-radiolysis technique combined with the atomic resonance absorption method was used for the measurement of the room-temperature rate constants of the reactions of hydrogen and oxygen atoms with fluoroethylenes. The rate constants obtained at 298±2 K are as follows, in units of 10−12 cm3 molecule−1s−1 (1 cm3molecule−1 s−1=6.022×1017 m3 mol−1s−1). The standard deviation is within 10%.
    (Remark: Graphics omitted.)
    The correlation between the rate constants and the reactivity index calculated by the INDO method is discussed.
  • Hidetoshi Karasawa, Rei Yugeta, Akira Yamaguchi, Shin Sato
    1981 Volume 54 Issue 2 Pages 362-366
    Published: 1981
    Released: June 02, 2006
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    The γ-ray-induced oxidation of toluene in liquid carbon dioxide has been reinvestigated. In order to discuss the precursors of the main products: three kinds of cresols and benzyl alcohol, 1-butene was used as the scavenger of oxygen atoms. The formation of cresols and benzyl alcohol was well explained by the participation of two precursors: one is oxygen atoms and the other is ionic species, O or/and CO3 ions. The ratio of the G-value of oxygen atoms to that of the sum of O and CO3 ions initially formed was estimated to be 4 : 1 for pure liquid carbon dioxide. The spur model previously proposed was applied to explain the formation of O and CO3 ions.
  • Takahiko Ishiguro, Yoshiaki Hamada, Masamichi Tsuboi
    1981 Volume 54 Issue 2 Pages 367-374
    Published: 1981
    Released: June 02, 2006
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    Ultraviolet chemiluminescence caused by a reaction of metastable He and CF2Cl2 was observed. Laserexcited single-vibronic-level fluorescence of the CF2 ?dical thus produced was also examined. The main feature in the 250–400 nm region was explained as the CF2 \ ildeA1B1-\ ildeX1A1 transition. The observed vibrational-level population of CF2(\ ildeA1B1) resulting from this reaction exhibits a maximum near v2=5. This fact implies that the product has a FGF angle of about 104°, which is nearly equal to the FCF angle (105.4°) of the reactant (CF2Cl2) molecule, rather than to the equilibrium FCF angle (122°) of the CF2 (\ ildeA1B1) itself.
  • Keishiro Shirahama, Hidefumi Yuasa, Shinji Sugimoto
    1981 Volume 54 Issue 2 Pages 375-377
    Published: 1981
    Released: June 02, 2006
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    Interaction between sodium decyl sulfate and a cationic copolymer of dimethyldiallylammoniurn chloride and sulfur dioxide was studied by a potentiometric method utilizing a surfactant-selective electrode. Binding occurs suddenly and is completed in a very narrow range of equilibrium concentration, indicating the strongly cooperative nature of the binding process. The characteristic concentration at which binding starts is about two orders of magnitude smaller than the critical micelle concentration. The cooperativeness parameters as estimated by a nearest neighbor interaction model remains almost constant on increasing sodium chloride concentration, affinity for an isolated binding site decreasing.
  • Hiroshi Morita, Hiroshi Nakanishi
    1981 Volume 54 Issue 2 Pages 378-386
    Published: 1981
    Released: June 02, 2006
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    Near and vacuum UV absorption spectra have been measured with benzoylacetone (BA), dibenzoylmethane (DBM), and 3-phenyl-2,4-pentanedione (PPD) in heptane, in acetonitrile, and in ethanol at room temperature. Theoretical analysis of the spectra with the aid of the composite molecule method clearly shows that the π-electron interaction between the enol ring and the benzene ring is rather strong in BA and DBM, but is weak in PPD. The charge-transfer (CT) bands from the benzene ring to the enol ring are observed at 44000 cm−1 in BA, at 40000 and 44000 cm−1 in DBM, and at 41500 and 43800 cm−1 in PPD. The electronic structure of the enol form of malonaldehyde has been elucidated by a modified CNDO-CI method; the result indicates the first and second σ-σ* excited states predicted at 8.76 and 9.35 eV being the CT band pertinent to the intramolecular hydrogen-bonding.
  • Fujio Takahashi, Katsura Seki, Ryohei Kaneko, Kenji Sato, Yasushi Kusu ...
    1981 Volume 54 Issue 2 Pages 387-390
    Published: 1981
    Released: June 02, 2006
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    The role of irisquinone (IQ) in the chlorophyll-IQ electrode was studied by measuring the photoresponse under illumination and the photocurrent at the controlled potential. It was concluded that the hydrophobic property of IQ was necessary for the photoresponse to occur at the chlorophyll electrode, and that the photoexcited chlorophyll was likely to eject electrons to a counter electrode via an outer circuit and to pull electrons from the reduced IQ, which had been produced by the oxidation of a reducing compound in the electrolyte on the chlorophyll-IQ electrode.
  • Hisao Negita, Tsuneo Kubo, Hitoshi Kato
    1981 Volume 54 Issue 2 Pages 391-393
    Published: 1981
    Released: June 02, 2006
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    The 14N nuclear quadrupole resonance (NQR) was studied in four kinds of molecular complexes of urea, such as urea-nitric acid, urea-phosphoric acid, urea-oxalic acid, and urea-ammonium chloride. The 14N quadrupole coupling constants and asymmetry parameters at liquid nitrogen temperature are as follows: |e2Qqh|=3.157 MHz and η=0.475 for the HNO3 complex; |e2Qqh|=3.277 MHz and η=0.414 for the H3PO4 complex; |e2Qqh|=3.456 MHz and η=0.363 for the (COOH)2 complex; and |e2Qqh|=3.544 MHz and η=0.298 for the NH4Cl complex. From the temperature dependence of the resonance lines in these complexes, the strength of hydrogen bonds are discussed. The differences of the electron densities at the nitrogen atoms between urea and its complexes were derived from the corresponding NQR parameters, and the bond characters in these complexes are discussed.
  • Yashige Kotake, Keiji Kuwata
    1981 Volume 54 Issue 2 Pages 394-398
    Published: 1981
    Released: June 02, 2006
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    Electron spin resonance spectra of nitroxyl radicals bearing two asymmetric carbons were observed. The radicals were produced by the abstraction of a hydrogen atom from ethers and amines by photoexcited benzophenone, followed by spin trapping with phenyl-N-t-butylnitrone. The spectra showed the presence of two radical species assignable to diastereomers in most cases. The presence of isomers was seen more clearly in ESR spectra of radicals produced from ethers than those from amines. The origin of the different ESR parameters of the isomer was discussed in detail and it was concluded that the functional group on β-carbon acts as a group of proximity to nitroxyl function. The difference of the electronegativity of the atom in each functional group causes the difference of the extent of the separation of isomers. The effects of proximity groups on observed ESR parameters are concluded to be the same as the solvent effect.
  • Kiyoshi Iwamoto, Junzo Sunamoto
    1981 Volume 54 Issue 2 Pages 399-403
    Published: 1981
    Released: June 02, 2006
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    A fluorescent probe, N-dansylhexadecylamine (DSHA), was found to aggregate in aqueous media by monitoring the emission maximum, relative intensity, and polarization of fluorescence as functions of solvent polarity and probe concentration. In aqueous methanol, the critical solvent polarity for DSHA at a given concentration to form self-aggregates corresponded to 57% (v/v) aqueous methanol, while the critical aggregate concentration for the probe was 2.3×10−6 M in 50% aqueous methanol. In liposomal bilayers, the dansyl moiety seemed to be localized in a polar region close to the surface of membranes. Fluorescence characteristics of DSHA in liposomes as a function of incubation temperature revealed the phase transition of liposomal bilayers, which was almost consistent with those previously estimated by other methods. As the salt concentration was increased up to about 1.5 M, DSHA in liposomes underwent the phase separation and formed self-aggregates even in liposomal bilayers.
  • Hiroshi Yoneyama, Toshikazu Ohkubo, Hideo Tamura
    1981 Volume 54 Issue 2 Pages 404-407
    Published: 1981
    Released: June 02, 2006
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    CdSnO3 sinter electrodes work as n-type photoanodes with a high electrochemical stability in alkaline solutions. A thin film LaRhO3 electrode prepared on a substrate platinum plate shows p-type photoresponse in aqueous solutions, giving rise to the hydrogen evolution with a fair stability. The threshold wavelength beyond which no photoresponse appears is ca. 700 nm for the former and 950 nm for the latter electrode.
  • Yohji Achiba, Tomoko Yamazaki, Katsumi Kimura
    1981 Volume 54 Issue 2 Pages 408-412
    Published: 1981
    Released: June 02, 2006
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    Experimental processes recently developed to determine differential and partial photoionization cross sections of molecules are described in detail, based on photoelectron intensity measurements using a gaseous binary mixture of a sample with a standard gas. The quantities obtained here in these processes are 1) relative photoelectron peak heights, 2) normalized photoelectron spectra, 3) relative photoelectron band areas, and 4) differential and partial photoionization cross sections. Corrections are made for electron collecting efficiency. In connection with the photoelectron intensity determination, we propose here a method of obtaining the mole ratio of the components of a binary mixture entered into the ionization chamber of a photoelectron spectrometer. Satisfactory results on partial photoionization cross sections have been obtained for several testing samples.
  • Keiichiro Hatano, Kiyoko Usui, Yoshitaka Ishida
    1981 Volume 54 Issue 2 Pages 413-419
    Published: 1981
    Released: June 02, 2006
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    Trivalent cobalt ion coordinated to 5,10,15,20-tetra(p-sulfophenyl)porphine (TPPS) in deaerated solution was reduced to the divalent ion on illumination of light with simultaneous oxidation of alcohols. The resulting divalent ion in the porphyrin was reoxidized by admission of dioxygen or air into the solution. It was found that the metalloporphyrin played a photocatalytic role in the autoxidation of alcohols. The kinetic study on the photoreduction revealed that the reduction rate of Co(III) followed the pseudo-first-order rate expression at 20 °C and pH 6.5 to 11.5 in the presence of excess methanol or 2-propanol. The observed rate constants were dependent on [alcohol] and/or pH. Possible mechanism for the photoreduction of Co(III)TPPS in the aqueous solution was discussed in terms of preequilibrium reactions of the axial ligation of substrates to the metalloporphyrin.
  • Naomi Hoshino, Yutaka Fukuda, Kozo Sone
    1981 Volume 54 Issue 2 Pages 420-427
    Published: 1981
    Released: June 02, 2006
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    A new series of mixed chelates of nickel(II), Ni(diam) (β-dik)X·nH2O (X= halide or pseudohalide anion, n=0–2), was prepared, and their structures in solid state and in various organic solvents were studied. Most of the chelates were octahedral, many of them being obtained as mono- or dihydrates. When the solid chelates were heated at reduced pressure, the main reactions were dimerization (X=pseudohalide), dehydration (X=I), and disproportionation (X=Br or Cl). On the other hand, the chelates showed complicated structural changes in organic solvents, some of which were not observed in solids, depending upon the nature of X and the polar characteristics of the solvent.
  • Yutaka Fukuda, Noriko Sato, Naomi Hoshino, Kozo Sone
    1981 Volume 54 Issue 2 Pages 428-432
    Published: 1981
    Released: June 02, 2006
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    The visible absorption spectra of three new mixed chelates of copper (II), Cu(tmen)(acac)X(tmen=N,N,N′,N′-tetramethylethylenediamine, acac=acetylacetonate ion, X=NCS, N3, or NCO) were studied in various organic solvents. It was found that the \ ildeνmax values of their d-d bands depend strongly on the nature of the solvent, and shift in the opposite direction as compared with the case of [Cu(tmen)(acac)]ClO4 studied before, where \ ildeνmax shifted to red with the increase of the donor number (DN) of the solvent. Here the magnitude of the red shift is affected not only by the DN, but also by other parameters of the solvent polarity, such as Kosower’s Z or Reichardt’s ET. The obtained data can reasonably be explained, if an equilibrium
    [Cu(tmen) (acac)X]\ ightleftarrows[Cu(tmen)(acac)]++X
    (5−coordinated)(4−coordinated)
    (with axial solvation)
    is assumed to exist in such solutions.
  • Takashi Shibahara, Masayasu Mori, Keiji Matsumoto, Shun’ichiro O ...
    1981 Volume 54 Issue 2 Pages 433-435
    Published: 1981
    Released: June 02, 2006
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    The crystal structure of [(en)2Co(NH2)(O2)Co(en)2](NO3)3·15/8(AgNO3)·H2O has been determined from X-ray diffraction data collected by the counter method. The crystal is monoclinic with the space group C2/c and with a=8.710(3), b=16.413(5), c=20.024(8)Å, β=90.30(4)°, and Z=4. The structure was refined by the block-diagonal least-squares method to R=0.107 for 2157 independent reflections. It has been elucidated that the Ag atom is bound to each of the two peroxo oxygen atoms with the Ag–O bond length of 2.27(1) Å. Each Ag atom is also surrounded by two more oxygen atoms belonging to the nitrate anions and these Ag–O bond lengths are 2.45(2) and 2.50(2) Å. The central five-membered ring has a symmetric envelope conformation, with the peroxo O atom deviating from the Co, N, Co plane, by 0.38 Å. The crystals contain an equal amounts of the enantiomeric forms (δδΛδδδ) and (λλΔλΔλλ). The formation constant of Ag+ and [(en)2Co(NH2)(O2)Co(en)2]3+ in aqueous solution was found to be less than 0.5.
  • Susumu Okazaki, Mituo Yamazaki
    1981 Volume 54 Issue 2 Pages 436-440
    Published: 1981
    Released: June 02, 2006
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    The maximum value in the number of acid sites per unit of surface area of the gypsum formed in the reaction between Ca(NO3)2 and H2SO4 was observed at the heat-treatment temperature of 200 °C, corresponding to the dehydration temperature for the change from its hemihydrate form to soluble anhydrite. The IR-absorption spectra of the gypsum showed no bands assignable to isolated OH groups or Ca–OH species. The IR spectra of the pyridine adsorbed on the gypsum showed only the bands due to Lewis-acid sites. The gypsum heat-treated at temperatures lower than 500 °C showed catalytic activities for the double-bond isomerization of 1-butene. The cis-/trans- ratio of 2-butene was 2–2.5, showing that the catalytic activity was due to Lewis acid, not to Brönsted acid. The isomerization of cyclopropane to propene was scarcely promoted by the gypsum at 250 °C. This fact is another indication of the absence of Brönsted acid sites on the heat-treated gypsum. Most of the weak Lewis acid sites (H0≤+4.8) were ascribable to exposed Ca2+ ions surrounded by monodentate sulfate ions on the surface of metastable anhydrite III-CaSO4.
  • Masayasu Iida, Hideo Yamatera
    1981 Volume 54 Issue 2 Pages 441-444
    Published: 1981
    Released: June 02, 2006
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    The aquation of the pentaamminefluorochromium(III) complex was found to be assisted by the aluminium ion. The observed pseudo-first-order rate constant, kobsd, can be written approximately as: kobsd=kAl[Al3+] (kAl=7.5×10−4 dm3 mol−1 s−1 at 35 °C, pH 3.0, I=2.0 mol dm−3). The rate constant decreased with an increase in the hydrogen-ion concentration, and this hydrogen-ion dependence was explained by assuming that the attack of aluminium ions on CrF(NH3)52+ was blocked by the protonation of the fluoro ligand. The analysis of the experimental results gave 3.0±0.1 for the logarithm of the protonation constant. The effects of ClO4 and Co(CN)63− on the reaction rate were explained by considering the formation of ion-pairs between the anions and the reacting cations.
  • Osamu Yamaguchi, Kazuhiro Tominaga, Kiyoshi Shimizu
    1981 Volume 54 Issue 2 Pages 445-447
    Published: 1981
    Released: June 02, 2006
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    Amorphous BaSiO3 or a mixture of this and BaSiO3·H2O was formed by the simultaneous hydrolysis of barium and silicon alkoxides. The temperature of hydrolysis and the time of aging influence the crystallization of amorphous BaSiO3 into BaSiO3·H2O. The decomposition of BaSiO3·H2O into crystalline BaSiO3 was analyzed by isothermal thermogravimetry. Decomposition isotherms were constructed by the equation −ln(1−α)=kt and the activation energy was determined as 143.5 kJ/mol. The kinetics of crystallization of amorphous into crystalline BaSiO3 was interpreted by the equation 1−(1−α)1⁄3=kt. Activation energies were 276 kJ/mol and 204 kJ/mol for the initial and final stages, respectively.
  • Tomoharu Ama, Hiroshi Kawaguchi, Takaji Yasui
    1981 Volume 54 Issue 2 Pages 448-451
    Published: 1981
    Released: June 02, 2006
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    The relationship between the ligand field of the carboxyl groups and the chemical shift of carboxyl carbon or α-carbon has been investigated on the basis of the absorption and 13C-NMR spectral data of the trans(O)-[Co-(OCO-R)2(en)2]Xn type complexes (OCO-R denotes amino acid or fatty acid coordinating unidentately with the carboxyl group to cobalt (III)). The linear correlations were observed between the \barνmax (1Eg component of the first absorption band) and the chemical shifts of carboxyl- and α-carbons.
  • Yoshihisa Matsuda, Sunao Yamada, Takashi Goto, Yukito Murakami
    1981 Volume 54 Issue 2 Pages 452-457
    Published: 1981
    Released: June 02, 2006
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    The redox chemistry of acetato(5,10,15,20-tetraphenylporphinato)oxoniobium(V) (1) was investigated in dichloromethane by means of cyclic voltammetry and controlled potential electrolysis. One-electron reduction potentials were observed at −0.89, −1.05, and −1.41 V vs. SCE for the range from 0 to −2.0 V; the reduction of niobium(V) to niobium(III) occurred prior to ligand-reduction. The potential separation between first and second metal-reductions (ΔE1⁄2) for 1 is 0.16 V, while ΔE1⁄2 between reductions of the MoVI and MoV species for the corresponding molybdenum complex is 1.24 V. In order to elucidate the origin of such potential difference between the niobium and molybdenum complexes, the change of coordination structures which takes place in the course of redox reactions was examined. The coordination reaction of 1 with pyridine was also studied.
  • Fumio Wada, Yoshiko Wada, Kiyoshi Kikukawa, Tsutomu Matsuda
    1981 Volume 54 Issue 2 Pages 458-461
    Published: 1981
    Released: June 02, 2006
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    The effect of crown ethers on the acid-base interaction of 2,4,4′,6-tetranitrodiphenylamine (HA, λmax 380 nm, pKa=8.88 in water) with primary amines (RNH2) in benzene was investigated spectrophotometrically. Crown ethers assisted strongly the formation of association complexes, R\overset+NH3·crown ether·A, which existed as a single chemical species (λmax 478 nm) assignable to “crown ether-separated ion pair.” The effect of the steric factors of various primary amines on the equilibrium to form the association complex was discussed on the basis of the equilibrium constants and thermodynamic parameters of the systems involving 18-crown-6 and benzo-18-crown-6.
  • Kiyoshi Mutai, Keiji Kobayashi
    1981 Volume 54 Issue 2 Pages 462-465
    Published: 1981
    Released: June 02, 2006
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    Intramolecular rearrangement was induced by light as well as base in a homologous series of 1-(p-nitrophenoxy)-ω-anilinoalkanes, p-O2NC6H4O(CH2)nNHPh(n=2–5), yielding N-(p-nitrophenyl)-ω-anilino-1-alkanols, p-O2NC6H4N(Ph)(CH2)nOH. The reaction rate in acetonitrile showed abnormal order, n=4>5>3>2, which was reversed by the addition of triethylamine. The mechanism of this photorearrangement through a radical ion pair and a spiro type Meisenheimer complex was proposed. The anomaly in the reaction rate order was discussed on the basis of this mechanism.
  • Kazuhisa Abe, Hiroko Endo, Minoru Hirota
    1981 Volume 54 Issue 2 Pages 466-469
    Published: 1981
    Released: June 02, 2006
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    The equilibrium constants for the hydration reaction of 4-pyridinecarbaldehyde were determined in several solvents by 1H-NMR spectroscopic measurements. The hydration reactions were sensitive to the nature of the solvents. In strong donor solvents such as hexamethylphosphoric triamide, pyridine, and dimethyl sulfoxide, formation of the hydrate is far more favorable than in water or other poor donor solvents. Thus the stabilization of the product by hydrogen bond formation is assumed to favor the reaction. Polarity of the solvent alone does not explain the solvent effect, even if it is supposed to affect the equilibria secondarily.
  • Koichi Mizusaki, Satoru Makisumi
    1981 Volume 54 Issue 2 Pages 470-472
    Published: 1981
    Released: June 02, 2006
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    Diastereomeric γ-hydroxy-L- and D-ornithines were prepared by reduction of the corresponding γ-oxoornithines synthesized from L- and D-histidines with sodium borohydride. The isomeric composition of the product obtained from L-histidine was estimated to be 68% erythro and 32% threo isomers and that of the product from D-histidine 65% erythro and 35% threo isomers by automatic amino acid analysis after conversion of the basic amino acids into neutral Nδ-acetyl derivatives. The diastereoisomers of each γ-hydroxyorni thine were separated by chromatography on a Dowex 50 column, four optically active isomers being isolated as their hydrochlorides in crystalline state. Guanidination of these isomers with 1-amidino-3,5-dimethylpyrazole nitrate (ADPN) gave the corresponding optically active isomers of γ-hydroxyarginine which were isolated as crystalline hydrochlorides. Erythro-γ-hydroxy-L-arginine hydrochloride shows a specific rotation which agrees very closely with that of natural product of γ-hydroxyarginine.
  • Gaku Yamamoto, Michinori Oki
    1981 Volume 54 Issue 2 Pages 473-480
    Published: 1981
    Released: June 02, 2006
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    Stereodynamics of a variety of 9-(3,5-dimethylbenzyl)triptycene derivatives was studied. Atropisomerism about the bridgehead-to-methylene bond was realized in a triply peri-substituted derivative, 8,13-dichloro-1,4-dimethyl-9-(3,5-dimethylbenzy)triptycene: the activation enthalpy for the ap→±sc conversion was 26.4 kcal/mol. Barriers to rotation about the bridgehead-to-methylene bond in a variety of triply, doubly, and singly peri-substituted derivatives were obtained by DNMR method. DNMR behavior of the diastereotopic m-methyl groups in the benzyl moiety revealed the dual mechanisms of the methyl exchange process: rotation about the methylene-to-aryl bond by 180° without rotation about the bridgehead-to-methylene bond (“isolated rotation (IR)”) and rotation about the methylene-to-aryl bond by 180° synchronous with rotation about the bridgehead-to-methylene bond by 120° (“gear motion (GM)”). The GM process predominates in peri-unsubstituted derivatives, while the IR process predominates in triply peri-substituted ones.
  • Gaku Yamamoto, Michinori Oki
    1981 Volume 54 Issue 2 Pages 481-487
    Published: 1981
    Released: June 02, 2006
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    DNMR study of a series of singly peri-substituted 9-(2-methylbenzyl)triptycene derivatives showed that the interconversion among the ap and ±sc rotamers with the o-methyl group pointing outside the triptycyl skeleton occurs by two consecutive gear motion steps by way of the unstable rotamers with the o-methyl group pointing inside. The+sc\ ightleftharpoons−sc interconversion barriers (13.2—14.1 kcal/mol) are lower than the ap\ ightleftharpoons±sc ones (17.7–20.8 kcal/ mol). The aryl group passes over a peri-hydrogen at the transition state of the former process and over the peri-substituent in the latter.
  • Yutaka Saitoh, Yoshihiko Moriyama, Hiroshi Hirota, Takeyoshi Takahashi ...
    1981 Volume 54 Issue 2 Pages 488-492
    Published: 1981
    Released: June 02, 2006
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    L-Serine was transformed in 8 steps into (4R,5S)-2,2-dimethyl-4-[(Z)-3-pentadecenyl]-1,3-dioxan-5-amine. This chiral ε,ζ-unsaturated amine was subjected to intramolecular aminomercuration and then acid hydrolysis to give (−)-deoxoprosopinine and (−)-deoxoprosophylline.
  • Yumihiko Yano, Shuji Kawada, Waichiro Tagaki
    1981 Volume 54 Issue 2 Pages 493-495
    Published: 1981
    Released: June 02, 2006
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    The acid dissociation constants of carbon acids activated by two sulfonyl groups were determined spectrophotometrically in aqueous solution with and without GTAB micelles. The results indicate that a cationic micelle causes larger pKa decrease for more hydrophobic disulfones. Hydrophobic properties of cyclic and acyclic disulfones are discussed.
  • Masaharu Iwakawa, Juji Yoshimura, Masuo Funabash
    1981 Volume 54 Issue 2 Pages 496-500
    Published: 1981
    Released: June 02, 2006
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    The Michael addition of 2-lithio-1,3-dithiane to 3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-6-nitro-β-L-arabino-hex-5-enofuranose afforded a 1 : 1.8 mixture of 3-O-benzyl-5,6-dideoxy-5-C-(1,3-dithian-2-yl)-1,2-O-isopropylidene-6-nitro-α-D-galactofuranose and-β-L-altrofuranose. Removal of the isopropylidene group and intra-molecular cyclization under weakly basic conditions afforded a mixture of branched-chain cyclitols having neo-, myo-, and chiro-configuration. A similar cyclization of the O-deisopropylidenated product of 3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-6-nitro-5-C-(nitromethyl)-β-L-arabino-hexofuranose also afforded a mixture of cyclitols having neo-, myo-, and chiro-configuration. The results confirm the importance of two bulky groups such as benzyloxy at C-3 and 1,3-dithiane residue at C-5 in determining the stereodirection of cyclization.
  • Mitsuaki Ohmori, Masanosuke Takagi
    1981 Volume 54 Issue 2 Pages 501-504
    Published: 1981
    Released: June 02, 2006
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    The d.c.-polarogram of ninhydrin (I) in DMF containing 0.1 M TEAP shows three cathodic waves whose E1⁄2 are −0.38, −0.65, and −1.23 V (vs. SCE), respectively. The first wave with a large maximum is attributed to one-electron reduction of 1,2,3-indantrione (II), the hydrated form of I, the second to one-electron reduction of I, and the third to one-electron reduction of the preceding electrochemical product from both I and II. CV Curves of I show three cathodic peaks, pc1, pc2, and pc3, and two anodic peaks, pa1 and pa2, showing reversible character of pc1 and pc3 but not of pc2. Different equilibria seem to take place between I and II in the bulk of the solution and at electrode surface. Hydration of II and dehydration of I in DMF were observed at 550 nm spectroscopically. A scheme is proposed for the electrolytic reduction of I in DMF.
  • Toshio Sato, Tatsuo Kawara, Kazumi Sakata, Tamotsu Fujisawa
    1981 Volume 54 Issue 2 Pages 505-508
    Published: 1981
    Released: June 02, 2006
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    Jasmonoids with cis-2-pentenyl side chain such as cis-jasmone, methyl jasmonate, and jasmolone were easily synthesized from cis-4-heptenoic acid obtained by the ring opening reaction of β-propiolactone with di-cis-butenylcuprate.
  • Taketsugu Hirai, Isao Tari, Tsutomu Ohzuku
    1981 Volume 54 Issue 2 Pages 509-512
    Published: 1981
    Released: June 02, 2006
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    The differential capacitance (C) and the photocurrent onset voltage (Ep) of nitrogen-stabilized n-TiO2 semiconductor electrodes were measured in buffered Na3PO4 solutions. The C−2 vs. E plots did not show the Mott-Schottky (MS) behavior. In order to explain the nonlinearity in MS plots, the distribution in donor density (Nd) at the solid side and the contribution of the electrical double layer at the solution side to the total capacitance were considered. The characterized flat-band potential (Efb) and the zero-charge potential (Ezc) were defined from the derived equations. The roles of the defined Efb and Ezc in the photocurrent onset voltage (Ep) were also considered, and the reason why Ep differed from Efb was explained using the “Gate” model.
  • Hiroshi Shimizu, Akira Kaito, Masahiro Hatano
    1981 Volume 54 Issue 2 Pages 513-519
    Published: 1981
    Released: June 02, 2006
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    The induced circular dichroism (ICD) spectra of β-cyclodextrin (β-CDx) complexes with o, m, and p-disubstituted benzenes were observed. The comparison of the observed rotational strengths with the ones calculated by using the Kirkwood-Tinoco expression is examined; the possible orientations of the guest molecules which are included in the cavity of β-CDx are presented. These results suggest that the orientation of the guest molecule is confined about the axis of the β-CDx torus.
  • Yoshiaki Ogo, Noboru Nishiguchi, Yasuhiro Okuri
    1981 Volume 54 Issue 2 Pages 520-525
    Published: 1981
    Released: June 02, 2006
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    An apparatus for investigating mechanochemical reactions at high pressures of up to 50 kbar and preliminary experiments on acrylamide are described. The essentials of the apparatus are a rotating platen inserted in a Bridgman-type opposed-anvil press. The central platen is rotated by the force of an electric motor or by manual strokes under high pressure. The pressure distribution on the anvil surface was evaluated from the changes in the electric resistances of CdSe and CdTe as calibrants. The pressure observed at the center was 4.5 times the nominal load pressure. The phase-transition pressure of naphthalene was identified as about 25 kbar from the measurement of the pressure effect on the shearing strength. The mechanochemical behavior of acrylamide was investigated at room temperature and at static pressures of up to 15 kbar. The determinations of the IR spectrum, the ESR signal, the X-ray diffraction pattern, and the molecular weight confirmed that the reaction products were amorphous polyacrylamides and that the mechanical shear stress on the conversion of acrylamide to a polymer was exceedingly effective in comparison with static pressure.
  • Yasuyuki Takeda
    1981 Volume 54 Issue 2 Pages 526-529
    Published: 1981
    Released: June 02, 2006
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    The solvent extraction of rubidium and caesium picrates has been studied between benzene and water at 25 °C in the presence of tributyl phosphate (B), 12-crown-4 (12C4), 15-crown-5 (15C5), or both B and 15C5, and the complex-formation constants for the synergistic reactions in the benzene solution have been calculated. For both rubidium and caesium, the sequences of the complex-formation constants for these ligands are B<12C4<15C5, indicating that the complex-formation constant increases with an increase in the number of the donor oxygen atoms of the ligand. The complex-formation constant of rubidium is greater than that of caesium in every system.
  • Tohru Koike, Kihei Morinaga
    1981 Volume 54 Issue 2 Pages 530-534
    Published: 1981
    Released: June 02, 2006
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    Absorption measurements at 216 and 230 nm of shock heated C2H2, C2H2+H2, and C2H4 diluted in Ar were made over the temperature range 1800 K to 2600 K at half of atmospheric pressure. Absorptivities were evaluated for C4H2, which is the main product of C2H2 pyrolysis, as well as for C2H2 and C2H4. The relative value of C4H2 absorption was confirmed to decrease with the presence of H2 in accordance with a computer modeling result using a 25-reaction mechanism. The time profile of C4H2 absorption could be modeled well with k=1012.4 cm3 mol−1 s−1 for the reaction H2+C2H=C2H2+H.
  • Takashi Kakiuchi, Mitsugi Senda
    1981 Volume 54 Issue 2 Pages 535-539
    Published: 1981
    Released: June 02, 2006
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    The adsorption of D-, L-, and DL-phenylalanines at the mercury-aqueous sodium fluoride solution interface has been studied by measuring differential capacities, potentials of zero charge, pzc, and surface tensions at the pzc. The racemate of phenylalanine showed higher surface activity than the enantiomers. This difference has been interpreted in terms of the intermolecular interactions, orientation and re-orientation of adsorbed molecules at the interface.
  • Mikio Morita, Kunio Hirosawa, Toshio Sato, Koji Ouchi
    1981 Volume 54 Issue 2 Pages 540-544
    Published: 1981
    Released: June 02, 2006
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    Triphenylmethane and 9,10-dihydroanthracene were found to produce colored complexes when placed in contact with molten zinc chloride or with solid zinc chloride pulverized or supported on porous Vycor glass. The triphenylmethane complex gave the same electronic absorption spectrum as that of the triphenylmethyl cation generated by contact with silica-alumina and BF3 on silica. The 9,10-dihydroanthracene complex exhibited the same electronic absorption band as that of the 9-anthracenium ion produced by the reaction of anthracene with concd H2SO4. The reaction of the triphenylmethane complex with deuterium gas provided HD gas and (C6H5)3CD. Similarly, the 9,10-dihydroanthracene complex and deuterium gas produced HD gas and 9,10-dihydroanthracene-9-d. Furthermore, their colored complexes on the supported zinc chloride gave a very weak IR absorption band at about 1720 cm−1, which is interpreted as corresponding to the formation of a Zn–H bond. These observations led us to conclude that triphenylmethane and 9,10-dihydroanthracene dissociate into ions . upon contact with zinc chloride:
    (C6H5)3CH+nZnCl2 \ ightleftarrows (C6H5)3C+(ZnCl2)nH
    (Remark: Graphics omitted.)
  • Nobuo Nishino, Masao Nakamura
    1981 Volume 54 Issue 2 Pages 545-548
    Published: 1981
    Released: June 02, 2006
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    Measurements were made of the solubility vs. temperature curves of water in normal alkane derivatives: alkanols, alkylamines, and alkanoic acids. The solubility of water increases monotonically with an increase in the temperature in alkanols and alkanoic acids, while it decreases in alkylamines. The solubility is so great that it often exceeds 1/2 in the mole fraction scale. Phase diagrams were constructed by combining such solubility curves with the solubility curves of these substances in water. The heat of solution at an infinite dilution vs. the temperature for 1-butanol in water is obtained by taking account of the activity coefficient of 1-butanol in its own phase.
  • Shigeru Ikuta, Akira Kira, Masashi Imamura, Izumi Motoyama, Hirotoshi ...
    1981 Volume 54 Issue 2 Pages 549-551
    Published: 1981
    Released: June 02, 2006
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    The absorption spectra of the transient species produced through the one-electron reduction of ferrocene and biferrocene were determined by applying a radiation-chemical method in frozen glass matrices. The spectral shapes were assigned to ferrocene- and biferrocene-anionic species on the basis of the experimental results. In the biferrocene anion, the “intervalence transfer” band was observed at about 2050 nm.
  • Sumio Ozeki, Shoichi Ikeda
    1981 Volume 54 Issue 2 Pages 552-555
    Published: 1981
    Released: June 02, 2006
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    Light scattering from solutions of dodecyltrimethylammonium chloride in water and 4.00 M (1 M=1 mol dm−3) NaCl has been measured at 25 °C, and the critical micelle concentrations and the micellar molecular weights have been determined. The critical micelle concentration, when combined with the previous data, follows the linear Corrin-Harkins equation over the whole range of NaCl concentrations. The micellar molecular weight remains low, i.e., about 20000 even in the presence of 4.00 M NaCl, and the double-logarithmic relation between the micellar molecular weight and the ionic strength is represented by a straight line over the whole range of NaCl concentrations, when plotted together with the previous data. These results indicate that only spherical micelles are formed by dodecyltrimethylammonium chloride in the presence of added NaCl. The stability of the spherical micelle is attributed to the low degree of binding of Cl on the cationic micelles.
  • Zenko Yoshida
    1981 Volume 54 Issue 2 Pages 556-561
    Published: 1981
    Released: June 02, 2006
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    The thermal evaporation of mercury is investigated in order to ascertain the structure of mercury electrodeposited on platinum. At first, Pt2Hg is formed on platinum, and a hydrogen(H)-overpotential at the surface is identical with that at the mercury-free platinum. With the increase in the amount of mercury to more than the amount corresponding to PtHg, the H-overpotential increases. When a large amount of mercury is deposited, the layer is composed of three mercury compounds (Pt2Hg, Pt2Hg2, and PtHg4), metallic mercury, and adatom mercury. Even when a sufficiently large amount of mercury is deposited, e.g., several thousand atomic layers, the H-overpotential is much less than that at a hanging mercury drop electrode (HMDE). From the general relationship between the hydrogen evolution at a metal electrode and the work function of the metal, the change in the H-overpotential with the increase in the amount of mercury is attributable to the work-function change.
  • Zenko Yoshida
    1981 Volume 54 Issue 2 Pages 562-567
    Published: 1981
    Released: June 02, 2006
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    In order to get an ideal thin mercury film electrode, the structure of mercury film electrodeposited on foreign metals was investigated with the aid of the thermal-evaporation behavior of mercury and correlated to the electrode properties of the mercury-deposited surfaces. A mercury layer deposited on gold, copper, nickel, or platinum consists of stable mercury compounds with the base metal at their interface and a uniform metallic mercury layer on them. The hydrogen(H)-overpotential at the mercury-coated surface increases with the increase in the amount of mercury deposited. Mercury on molybdenum or stainless steel forms island-like metallic mercury droplets by electrodeposition. The H-overpotential at the surface is identical with that at molybdenum or stainless steel without mercury. Mercury deposited on lead or zinc easily forms a stable amalgam with the base metal, and no metallic mercury is present. The H-overpotential at the surface is slightly less than that at a base metal without mercury. A nickel-based thin mercury film electrode is recommended for such electroanalytical uses as anodic stripping voltammetry.
  • Tsukio Ohtani, Koji Kosuge, Sukeji Kachi
    1981 Volume 54 Issue 2 Pages 568-575
    Published: 1981
    Released: June 02, 2006
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    The phase relation of (Ni1−xFex)1−yS system was determined by the X-ray powder diffraction method. Fe1−yS can be dissolved in Ni1−yS in ca. 30 at.%. Transition temperature (Tt) was measured mainly by the DSC method. Tt increases with increase in Fe contents. Tt in the forward direction, however, shows a significant increase as high as 50 degrees, when specimens are aged at a temperature below Tt. The reverse transformation is not affected by thermal hystory at all. This is explained by the relaxation process in which the strain energy stored in the low temperature phase is relieved by aging.
  • Katsutoshi Ohkubo, Kiyoshi Sugahara, Hidefumi Ohta, Katsuro Tokuda, Ry ...
    1981 Volume 54 Issue 2 Pages 576-580
    Published: 1981
    Released: June 02, 2006
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    The stereoselective deacylation of H–(CH2)\undersetn−1—CONHCH(R)CO2–C6H4NO2-p (R=CH3, CH(CH3)2, CH2CH(CH3)2, and C6H5CH2; n=2–16) with N-acyl-L-histidine (acyl=octanoyl, dodecanoyl, and hexadecanoyl) and cationic surfactants (CmH2m+1\overset+N(CH3)2R X; (R,X,m)=(CH3,Br,16), (C2H5,Br,16), (C6H5CH2,Cl,16), and (\overset*CH(CH3)C6H5,Br, 14–18) was examined with particular reference to the structural effects of surfactants, nucleophiles, and substrates on both the deacylation rates and the stereoselectivity. The cationic surfactant, R-(+)-C16H33\overset+N(CH3)2\overset*CH(CH3)C6H5 Br, which possesses the hydrophobic and chiral groups near the polar head, formed the stereoselectively most effective comicelles with N-dodecanoyl-L-histidine. The order of stereoselectivity observed in the deacylation of the amino acid esters including the identical acyl chain length (n), phenylalanine>leucine>alanine∼valine. suggested steric effects of the substituent bound to the asymmetric carbon atom of the substrate on the stereoselectivity. The highest stereoselectivity (enantiomer rate ratio=4.4 at 25 °C under pH 7.61) was observed in the deacylation of the N-decanoylphenylalanine p-nitrophenyl ester, involving an appropriately long acyl chain.
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