Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 54 , Issue 12
Showing 1-50 articles out of 61 articles from the selected issue
  • Minoru Kimura, Kiyoshi Nishikawa, Shigeyuki Aono
    1981 Volume 54 Issue 12 Pages 3619-3623
    Published: 1981
    Released: June 02, 2006
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    An theoretical investigation was made of the vibronic interaction between two electronic levels which are degenerate or nearly degenerate. Within the mean field approximation we derive a simplified effective Hamiltonian to analyze the problem of bond distortion of a molecule; the effective Hamiltonian is diagonalized by a linear canonical transformation of electronic operators. Thermodynamic arguments predict a possibility for appearance of a distorted phase below a characteristic temperature. The distorted phase is realized under a sufficiently strong coupling condition in a non-degenerate case, but under an arbitrarily small coupling condition in a degenerate case. The shift of electronic spectrum, the stabilization energy of the distortion, and thermodynamic quantities are expressed in terms of the parameters associated with the Hamiltonian. Change in electromagnetic properties due to the distortion is discussed. Magnitudes of the bond distortion and energy stabilization in the ground state are numerically estimated for cyclobutadiene, with results in good agreement with literature values.
  • Kiyoshi Nishikawa, Minoru Kimura, Shigeyuki Aono
    1981 Volume 54 Issue 12 Pages 3624-3627
    Published: 1981
    Released: June 02, 2006
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    Vibronic interaction between two closely-spaced electronic levels was investigated by use of the temperature Green’s function. A Green’s function version for the mean field approximation was derived which is capable of reproducing results obtained in the preceding work. The spectrum of phonon in the normal phase was then calculated and the critical (strictly speaking, characteristic, since we are dealing with a finite system) temperature Tc was obtained where the phonon becomes completely soft causing lattice distortion. The fluctuation effect was investigated and the mean field theory was examined for its applicability. When the level spacing is comparable to or larger than the value of the electron-phonon coupling constant, the mean field theory is satisfactory, but when the two levels are nearly degenerate, it is not so good because the problem in question is in the regime involving extremely strong coupling.
  • Kimio Isa, Hajime Ishimura
    1981 Volume 54 Issue 12 Pages 3628-3634
    Published: 1981
    Released: June 02, 2006
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    Ammonium heptamolybdate(6–) tetrahydrate (AHM) was studied by means of high temperature oscillating X-ray diffraction with a large capacity generator of 12 kW. Experimental conditions were determined precisely. It was possible to settle the maximum value of diffracted patterns, and the inherited error was about 1.5%. Thermal decomposition of AHM was studied by means of TG-DTA, but the first decrease of TG could not be explained as a single process of decomposition. Moreover it could also not be explained by means of high-temperature oscillating X-ray diffraction with a standard generator. However, with a large capacity generator, the first decrease of TG could be explained to be a convolution of three steps of decomposition. Moreover, the second and third steps could be explained by observing the microscopic structural change. In a high-temperature oscillating XRD, (heating rate 2 °C/min), a peak temperature of 96 °C was recognized, which had not been reported before. Also from 110 °C to 226 °C, a row of the small peak has been found. Finally, the first stage of decomposition which was thought to be a single step in the experiment of TG-DTA, could be seperated into three steps. Moreover, the onset and offset temperatures of changes of characteristic diffraction intensity are determined. It was proved that high-temperature oscillating X-ray diffraction is a powerful analysing method in thermal analysis.
  • Akira Kuboyama, Sanae Y. Matsuzaki
    1981 Volume 54 Issue 12 Pages 3635-3638
    Published: 1981
    Released: June 02, 2006
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    The phosphorescence spectra and their lifetimes of 9,10-anthraquinone and its 2-methyl and 2,3-dimethyl derivatives in various kinds of glassy solutions at 77 K have been obtained. In the non-hydrocarbon solutions, 2-methylanthraquinone shows, in most cases, a dual phosphorescence, consisting of a nπ* phosphorescence and a ππ* phosphorescence with different lifetimes, while 2,3-dimethylanthraquinone shows a very broad ππ* phosphorescence spectrum. The quinone-solvent interactions and the relative positions of the close-lying 3* and 3ππ* levels of these quinones are discussed on the basis of the experimental results.
  • Kunio Miki, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1981 Volume 54 Issue 12 Pages 3639-3647
    Published: 1981
    Released: June 02, 2006
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    The molecular structures of [Pd(CH2SCH3)(PPh3)2]PF6(3a) and [Pd(CH2SCH3)(PPh3)2]ClO4(3B) at −160°C were determined by means of X-ray diffraction. Crystals of both complexes belong to the monoclinic system: 3a, a=11.535(2), b=17.990(4), c=17.754(2) Å and β=101.07(1)°, space group P21/c with Z=4; 3b·CH2Cl2 solvate, a=11.496(5), b=20.872(9), c=15.056(6) Å and β=94.77(4)°, space group P21/n with Z=4. Both structures were solved by the heavy atom method and refined by the least-squares procedure to R=0.141 for 3906 reflections and R=0.102 for 4595 reflections for 3a and 3b respectively. The geometry around the Pd atom in each complex is essentially planar. However, the coordination behavior of the CH2SCH3 group in 3a and in 3b seems to be different. In 3a, the CH2SCH3 group is bonded to the Pd atom through the Pd–C σ-bond and the donation of the sulfur to the metal atom, forming a Pd–C–S three-membered ring [Pd–CH2=2.06(4), Pd–S=2.367(8), CH2–S=1.77(4) and S–CH3=1.78(4) Å]. On the other hand, the CH2SCH3 group in 3b is coordinated to the metal atom as a methylenemethylsulfonium ion, containing a C=S double bond[Pd–CH2=2.208(13), Pd–S=2.303(6), CH2–S=1.678(14) and S–CH3=1.86(4) Å].
  • Tsunemichi Okuwa, Kozo Ohno
    1981 Volume 54 Issue 12 Pages 3648-3650
    Published: 1981
    Released: June 02, 2006
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    Ultrasonic relaxational absorption was observed in solutions of NaI in i-PrOH. Assuming the excess ultrasonic absorption to be caused by the relaxation of the dissociation equilibrium of NaI in the solutions, the dissociation and recombination rates of NaI, the Arrhenius activation energy, and the enthalpy and volume changes due to dissociation were calculated; these were compared with the values estimated from other methods. An increase of the dissociation constant of NaI was observed with an increase in the concentration of H2O in i-PrOH–H2O mixtures.
  • Katsufumi Hashimoto, Hideo Fukutome
    1981 Volume 54 Issue 12 Pages 3651-3658
    Published: 1981
    Released: June 02, 2006
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    Electronic structures of low-lying states of cyclobutadiene, trimethylenemethane (2), and tetramethyleneethane (3) are studied by the unrestricted Hartree-Fock (UHF) theory. Characteristics of electronic correlations, called dynamical spin polarization effect, in these molecules are well described by corresponding orbitals and spin density structures of low-lying UHF solutions. The spin polarization of σ electrons is found to be relatively small but not negligible for quantitative discussion. The two low-lying singlet states of 2 are described by two UHF solutions with different spin density structures. The fact that the singlet UHF state of 3 lies a little below the triplet UHF state is explained by the difference in the spin polarization of the bonding π electrons between the singlet and triplet states. Two rules are given which predict the spin structure of low-lying UHF states and the spin multiplicity of ground states of hydrocarbon diradicals. These rules are applied to 1,1,2,3,3-pentamethylenepropane and 1,3-dimethylenecyclobutadiene, which confirms their validity.
  • Mitsuo Mashima, Fujiko Ikeda, Takako Doi, Sadakatsu Nishikawa
    1981 Volume 54 Issue 12 Pages 3659-3664
    Published: 1981
    Released: June 02, 2006
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    The rates of acid-catalyzed hydrolysis of formylhydrazine, acetylhydrazine, chloroacetylhydrazine, propionylhydrazine, butyrylhydrazine, and octanoylhydrazine in sulfuric acid–water mixtures have been investigated over a wide range of acidities (about 1–18 M H2SO4) by means of spectrophotometric methods. First-order kinetics were obtained in all cases, and the pseudo-first-order rate constants showed one of two types of acidity dependences: (i) a rate maximum at intermediate acidities, followed by slow hydrolysis in highly concentrated acids; (ii) a rate maximum at intermediate acidities, followed by a sharp increase in rate at high acidities. This result was treated as a function of the Hammett acidity function, the water activity, and the total concentration of hydrogen ion to yield reaction parameters which are explicable in terms of a change in mechanism at a high acidity from A-2 to A-1. The mechanism change also was deduced from a criterion based on the values of activation entropies.
  • Hisao Tanaka, Hiroko Nakagawa, Koh-ichi Yamada, Hiroshi Kawazura
    1981 Volume 54 Issue 12 Pages 3665-3668
    Published: 1981
    Released: June 02, 2006
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    In order to evaluate the influence of the staggered configuration of helicene on complex formation, a 1H NMR technique was applied to the complexing equilibria of thiaheterohelicene homologs with 7,7,8,8-tetracyanoquinodimethan (TCNQ). Formation constants of the complexes showed irregular changes in the case of [5] and [7]thiaheterohelicenes in which the staggerings occur. This irregularity could be interpreted on the basis of the observed abnormal decrease of the bonding entropy. The reduced bonding entropy was understood in terms of the incomplete quenching of internal freedom, which was expected from the peculiar orientation of the staggered thiaheterohelicene towards planar TCNQ, in the charge-transfer complex.
  • Hayao Kobayashi
    1981 Volume 54 Issue 12 Pages 3669-3672
    Published: 1981
    Released: June 02, 2006
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    The crystal structure of Rb–TCNQ-II was redetermined. The interplanar distance between the neighbouring TCNQ’s is 3.25 Å, which is almost equal to those of highly conducting TCNQ salts. The electrical resistivity and the structure of the TCNQ, columns suggest that the complete charge transfer in Rb–TCNQ-II makes this crystal low-conducting. The activation energy of the electrical conduction indicates that the dimerization gap appears below the monomer-dimer transition temperature. The temperature dependence of the electrical resistivities of Rb2TCNQ3 is also described.
  • Yukako Ohashi
    1981 Volume 54 Issue 12 Pages 3673-3676
    Published: 1981
    Released: June 02, 2006
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    To investigate the solvent dependence of the dd contribution to the lowest excited state of cis-[IrCl2L2]Cl (L=1,10-phenanthroline (phen) and 5,6-dimethyl-1,10-phenanthroline (5,6-Mephen)), the triplet-triplet absorption spectra (15000–25000 cm−1) were measured in N,N-dimethylformamide (DMF)–water mixed solvents. From a smaller solvent-dependence of the absorption intensity for [IrCl2(5,6-Mephen)2]Cl than for [IrCl2(phen)2]Cl, the lowest triplet state of the former is considered to have a ππ* character in 95% v/v DMF–water and 45% v/v DMF–water. However, in pure water a considerable decrease in the triplet-triplet absorbance was observed. Because the molar extinction coefficient of the triplet-triplet absorption of the dd-dd type is 10−2 times smaller than that of the ππ*-ππ* type, the observed decrease in the absorbance is elucidated by the increase in the contribution of the dd state to the lowest triplet state. Using ethanol–methanol (4 : 1, v/v) as a solvent, it was confirmed that the triplet-triplet absorption spectrum shows no change when the solutions are degassed and the temperature is lowered (77 K).
  • Shunzo Yamamoto, Masae Yasunobu, Norio Nishimura
    1981 Volume 54 Issue 12 Pages 3677-3680
    Published: 1981
    Released: June 02, 2006
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    Rate constants for the quenching of the cadmium resonance line at 326.1 nm by triethylamine (TEA), N-ethylpiperidine (NEP), and 1-azabicyclo[2.2.2]octane (ABCO) were obtained. Relative rate constants for the formation of an exciplex between an excited cadmium atom and these amines and quantum yields for the emission from the exciplex were also obtained. Contrary to the case of primary amines, in which the electron-donating ability of the nitrogen atom is operative, the exciplex formation in the present case is mainly governed by the magnitude of the steric effect of ethyl groups on the interaction between the nitrogen atom and an excited cadmium atom. Gaseous products were hydrogen, methane, ethane (and/or ethylene), and butane. The quantum yields of these products indicate that the primary photochemical products are methyl and ethyl radicals for TEA and NEP. The amount of products for ABCO was considerably smaller than those for other amines.
  • Yasuhiro Uosaki, Masaru Nakahara, Jiro Osugi
    1981 Volume 54 Issue 12 Pages 3681-3683
    Published: 1981
    Released: June 02, 2006
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    The 1,4-cycloaddition of TCNE to p-methyl-, p-chloro-, and p-bromostyrenes by way of the EDA complex has been studied in chloroform at 25 °C by the spectrophotometric method. The Hammett correlation obtained from the kinetic data provides −5.5±0.2 as the reaction constant ρ. The negative value is large in magnitude relative to other common 1,4-cycloadditions, suggesting some large partial charges in the rate-determining transition state. A linear correlation between the logarithmic forms of the reaction rate and the EDA-complex formation constant is in favor of the reaction scheme where the complex is on the pathway of the cycloaddition.
  • Ryuichi Minami, Koichi Itoh, Hiroaki Takahashi, Keniti Higasi
    1981 Volume 54 Issue 12 Pages 3684-3687
    Published: 1981
    Released: June 02, 2006
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    The concentration dependence of the principal relaxation times, τp, of primary alcohol/inert solvent solutions are analyzed based on the equation,
    τp=2(1+KxAH,
    where xA is the alcohol mole fraction, K the equilibrium constant corresponding to the formation of hydrogen bonded multimers, and τH the time constant characterizing the rotational activation process of the terminal OH groups of the multimers. By applying Eyring’s absolute rate theory to the activation process, we calculated τP as a function of temperature and alcohol concentration. The results reproduce quite well the τP values observed for the ethanol/cyclohexane, 1-hexanol/cyclohexane, and 1-propanol/benzene solutions.
  • Setsuo Takamuku, Hitoshi Kigawa, Susumu Toki, Kunihiko Tsumori, Hirosh ...
    1981 Volume 54 Issue 12 Pages 3688-3690
    Published: 1981
    Released: June 02, 2006
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    Reactions of the aromatic radical anions with benzhydryl chloride have been investigated by pulse radiolysis. The second-order rate constants were determined for the reactions of benzhydryl chloride with various aromatic radical anions. On the basis of the linear relationship between the free energy and the activation energy, an irreversible electron transfer with an early transition state was elucidated.
  • Ryosaku Igarashi, Fumisato Iida, Chiaki Hirose, Tsunetake Fujiyama
    1981 Volume 54 Issue 12 Pages 3691-3695
    Published: 1981
    Released: June 02, 2006
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    The polarization CARS spectra were observed for a few typical Raman lines at various experimental settings. Based upon the observed and calculated spectra, the usefulness and the validity of the polarization CARS method for the study of the overlapped Raman lines observed for a condensed system have been emphasized.
  • Yukio Fujii, Motoharu Tanaka
    1981 Volume 54 Issue 12 Pages 3696-3700
    Published: 1981
    Released: June 02, 2006
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    The partition of carboxylic acids between benzene and 0.1 mol dm−3(H,Na)ClO4 aqueous solution has been studied at 25 °C. Carboxylic acids used include acetic, propanoic, butanoic, pentanoic, hexanoic, and decanoic acids. The hydration of monomeric acids in benzene being taken into account, the hydration-corrected partition constant has been calculated. The effect of the chain length on the partition is accounted for with the aid of the newly estimated solubility parameters and empirical binary coefficients. Applicability of the empirical solubility parameter of water (35.89 J1⁄2 cm−3⁄2) has also been discussed.
  • Shigekazu Kumakura
    1981 Volume 54 Issue 12 Pages 3701-3705
    Published: 1981
    Released: June 02, 2006
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    The crystal structure of the title compound has been determined by means of X-ray diffraction. The space group is P\bar1 with a=11.665(4), b=8.775(4), c=7.092(2) Å, α=95.73(3), β=84.36(3), γ=104.90(2)°, and Z=2. The structure was refined to R=0.048 for 1770 reflections collected on a four-circle diffractometer. The thietane ring is puckered with dihedral angles, C(2)SC(4)/C(2)C(3)C(4) and SC(2)C(3)/SC(4)C(3), of 150.1° and 149.9° respectively. The conformation of the C–Cl bonds with respect to the thietane skeleton is (3e4e), consistent with that in solution derived from the dipole moments. The average distance of the two C–Cl bonds is 1.781 Å. The C(2)–S, C(4)–S, and C(2)–C(3) bond distances are 1.872(4), 1.811(5), and 1.545(6) Å respectively; agreeing well with the corresponding bond distances observed in the cis isomer of the compound; however, the C(3)–C(4) of 1.506(6) Å is much shorter. The bisector of the bond angle formed by the ring substituents at each of the ring atoms is tilted out of the corresponding CCC or CCS planes within the thietane ring so as to increase the staggering of the neighboring substituents. The angle of tilt at Cβ is larger than those at the Cα’s. The intermolecular S···S contact of 4.080(5) Å is normal in view of the usual van der Waals radii.
  • Hiromu Sugeta
    1981 Volume 54 Issue 12 Pages 3706-3710
    Published: 1981
    Released: June 02, 2006
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    A general method is developed for evaluating formation constants and molar absorption coefficients of constituent species from spectrophotometric data for a multicomponent equilibrium system. The method is applied to analyzing infrared spectra for the intermolecular hydrogen bond system of 2-aminopyridine in carbon tetrachloride solution. 2-Aminopyridine assumes a cyclic dimer structure by dint of an intermolecular hydrogen bonding and the formation constant for the dimerization is 1.4±0.1 mol−1 dm3 at 30 °C.
  • Bu Yong Lee, Yasunobu Inoue, Iwao Yasumori
    1981 Volume 54 Issue 12 Pages 3711-3716
    Published: 1981
    Released: June 02, 2006
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    The effects of ZrO2 upon the catalytic properties of α-alumina-supported palladium for the hydrogenation of gaseous cyclohexene were studied by means of detailed kinetic analysis, thermal desorption (TD), and X-ray photoelectron spectroscopy (XPS). The catalysts, with ZrO2 added in amounts ranging from 0.1 to 45 in Zr/Pd ratio, were characterized by CO chemisorption and X-ray diffraction. The addition of ZrO2 at the Zr/Pd ratio of 0.5 enhanced the turn-over frequency of the hydrogenation by a factor of 7 and changed the hydrogen order of the reaction from 1.0 to 0.75 and the cyclohexene order from 0 to 0.6. The reaction with D2 exhibited deuteriumdistribution patterns similar to those for the reaction on the ZrO2-supported Pd catalysts. The hydrogenation pathway on the ZrO2-added catalyst was described by an associative mechanism in which the slow step was a surface reaction between a cyclohexyl radical and a hydrogen atom. In the thermal desorption spectra, the addition of ZrO2 caused a broadening of the adsorbed hydrogen peak as well as a shift of the dissolved hydrogen peak toward a lower temperature. The desorption of cyclohexene from Pd/α-Al2O3 catalysts underwent a disproportionation to produce benzene around 318 K and cyclohexane at 368 K, whereas the latter peak shifted by 70 K to the lowertemperature side upon the addition of ZrO2. The XPS study showed that the presence of ZrO2 provided Pd metal atoms in a negatively-charged state. The support effect was discussed on the basis of the interaction between Pd metal atoms and ZrO2 oxide.
  • Haruo Nakayama
    1981 Volume 54 Issue 12 Pages 3717-3722
    Published: 1981
    Released: June 02, 2006
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    Solid-liquid and liquid-liquid phase diagrams of the binary R4NX–water (R=n-C3H7n-C6H13 and i-C5H11; X=F, Cl, Br, and I) systems were determined in the temperature range between −20 °C and +80 °C. These diagrams showed (1) the formation of a clathrate-like hydrate for four salts (n-C5H11)4NF, (n-C5H11)4NCl, (i-C5H11)4NBr, and (i-C5H11)4NI; (2) a phase separation into two liquid phases in the systems of (n-C5H11)4NBr, (i-C5H11)4NBr, (n-C6H13)4NCl, and (n-C6H13)4NBr; (3) that the solubility (in water at a definite temperature) of a series of the salts did not show a systematic change with respect to either the alkyl-chain length or the kind of anion; and (4) that the salt which gave the maximum solubility in water at 25 °C was (n-C5H11)4NCl for chloride, (n-C4H9)4NBr for bromide, and (C2H5)4NI for iodide, respectively. The effect of anions on the solubilities of a series of salts having the same cation was examined. It was found that the ratio mclmI at 25 °C became as high as 22800 for the tetrapentylammonium salts. Phase diagrams for the bolaform salt [(n-C4H9)3N(CH2)6N(nC4H9)3]X2–water systems are also presented.
  • Tateaki Ogata, Kazuo Oikawa, Tadashi Fujisawa, Shunsuke Motoyama, Taek ...
    1981 Volume 54 Issue 12 Pages 3723-3726
    Published: 1981
    Released: June 02, 2006
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    Electrode reactions of mono-, di- and tri-bridged ferrocenophanes ([3]Fcp, [4]Fcp, [3][3]Fcp, [4][3]Fcp, [4][4]Fcp, [3][3][3]Fcp, [4][4][3]Fcp and [4][4][4]Fcp) in acetonitrile were investigated by direct current polarography, pulse polarography, and cyclic voltammetry. The oxidation of these compounds proceeds reversibly as a one-electron process. The linear relationship between the half-wave potential and the number of methylene groups was obtained for ferrocene and ferrocenophanes other than [3][3]Fcp and [3][3][3]Fcp. The Taft substituent constants of trimethylene and tetramethylene groups were estimated.
  • Yasuyuki Takeda, Yoshimasa Wada, Shizuo Fujiwara
    1981 Volume 54 Issue 12 Pages 3727-3730
    Published: 1981
    Released: June 02, 2006
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    Benzo-15-crown-5 (B15C5) extracted alkali metal picrates (MA) into benzene by forming M(B15C5)A or M(B15C5)2A complexes and moreover, in the presence of tributyl phosphate (B), B15C5 extracted rubidium and caesium picrates by forming M(B15C5)BA complexes. The extractability sequences of the M(B15C5)A, M(B15C5)2A, and M(B15C5)BA complexes are Na+>K+>Rb+>Li+>Cs+,K+>Rb+>Cs+>, and Rb+>Cs+ respectively. The extraction equilibrium constants for these complexes have been determined at 25 °C, and the synergistic formation constants of the M(B15C5)2A and M(B15C5)BA complexes in the benzene solution have been calculated. The synergistic effects for the alkali metal ions for the B15C5 system were compared with those for the 15C5 system.
  • Takaaki Solin, Kazuko Matsumoto, Keiichiro Fuwa
    1981 Volume 54 Issue 12 Pages 3731-3734
    Published: 1981
    Released: June 02, 2006
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    From the reaction of cis-[Pt(NH3)2(H2O)2] with orotic acid, yellow needle crystals, green needle crystals, and dark-blue microcrystalline crystals were obtained. The results of elemental analyses, the IR absorption spectra, and X-ray Weissenberg photographs showed that the yellow and green needles are identical, whereas the dark-blue microcrystalline compound exhibits slight difference in the elemental analyses and IR spectra. Green needle crystals of cis-diammine(orotinato)platinum(II), cis-[Pt(NH3)2(C5H2N2O4)], were subjected to X-ray single crystal analysis. The crystals belong to the monoclinic system, with the space group P21/c, and the cell dimensions are a=7.468(5), b=7.537(3), c=15.618(9) Å, and β=107.90(7)°, with Z=4. The structure was solved by the heavyatom method and refined to the final R value of 0.0567 for 1918 non-zero reflections. The complex is almost planar, and the platinum atom is coordinated by the orotic acid at N1 and carboxylic oxygen, forming a fivemembered chelate ring. The structure of the pyrimidine ring of the orotic acid is compared with free and coordinated uracil and thymine. No definite explanation for the color difference was obtained.
  • Tetsuaki Nishida, Toshiharu Hirai, Yoshimasa Takashima
    1981 Volume 54 Issue 12 Pages 3735-3738
    Published: 1981
    Released: June 02, 2006
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    The Mössbauer technique at the liquid nitrogen temperature (78 K) was applied to the estimation of nonbridging oxygens in FeO4, BO4, and SiO4 units in potassium borosilicate glasses. Mössbauer spectra consist of a quadrupole doublet and a hyperfine structure due to Fe3+ ions with tetrahedral symmetry. The hyperfine structure is attributed to a relaxation effect because magnetic susceptibility measurements revealed the glasses to be paramagnetic in the temperature range 78–295 K. A linear decrease in the absorption area and a similar decrease in the internal magnetic field for the hyperfine structure were observed with an increase in the alkali content of glasses. The decrease is ascribed to a formation of non-bridging oxygen at the site adjacent to iron, because the mean life-time of the internal magnetic field produced by 3d-electrons of iron is considered to decrease with increasing thermal vibration of the iron and neighboring oxygens. Fractions of non-bridging oxygens obtained from the reduction rate of the absorption area of hyperfine structure are in good agreement with earlier results for borate glasses with the same K2O/B2O3 ratios, in the alkali region of 8–20 mol% where the borosilicate glasses are essentially considered to be borate glasses diluted with SiO2.
  • Goro Wada, Kumiko Takahashi, Masako Isobe
    1981 Volume 54 Issue 12 Pages 3739-3742
    Published: 1981
    Released: June 02, 2006
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    The electron transfer reaction Fe2+aq+Fe(phen)33+→Fe3+aq+Fe(phen)32+ has been investigated in order to find out the influence of the dielectric nature of media on the reaction rates, by the method of stopped-flow spectrophotometry. As the reaction media, were used aqueous mixtures with various alcohols, such as methanol, ethanol, 1-propanol, and ethylene glycol at their various mole fractions x. The second-order rate constant k grows larger approximately linearly with the increase in x, in a sequence: methanol<ethylene glycol<ethanol<1-propanol. When In k is plotted against D−1 (the reciprocal dielectric constant), all points come together on a single straight line with a positive slope, indifferent to the kinds of the alcohols used. This fact suggests that the reaction proceeds through three successive elementary processes, Fe2+aq+Fe(phen)33+\overseti→[Fe(H2O)62+·Fe(phen)33+]\oversetii→[Fe(H2O)63+·Fe(phen)32+]\oversetiii→Fe3+aq+Fe(phen)32+, in which Process i is the formation of an outer-sphere ion-pair between two reacting ions, Process ii the intramolecular electron transfer in the intermediate complex, and Process iii the separation of the ion-pair into the product ions, the last being the rate-determining step. The reaction scheme is compared with that of the reaction Fe2+aq+Fe(OH)2+→Fe(OH)2++Fe2+aq, where the first step of the ion-pair formation is rate-determining.
  • Takayuki Matsushita, Toshiyuki Shono
    1981 Volume 54 Issue 12 Pages 3743-3748
    Published: 1981
    Released: June 02, 2006
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    The reactions of the chloromanganese(III) complexes of the Schiff bases derived from salicylaldehydes or β-diketones and diamines or monoamines with superoxide ion, O2, in dimethyl sulfoxide were investigated. The complexes were found to react to give either the oxygenated Mn Schiff base complexes or the reduced Mn(II) Schiff base complexes. The difference in the reactivity toward O2 was correlated to the polarographic half-wave potentials corresponding to the reduction of Mn(III) to Mn(II) of the complexes. Some oxygenated complexes were isolated and characterized.
  • Noriyuki Nakasuka, Kenya Makimura, Hiroko Kajiura
    1981 Volume 54 Issue 12 Pages 3749-3752
    Published: 1981
    Released: June 02, 2006
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    Potentiometric titration was carried out at 25.0±0.1 °C and at an ionic strength of 1.00 mol dm−3 in sodium perchlorate for a system of copper(II)–dipeptide(A)–a second ligand(B) in an aqueous solution to obtain the formation constants of mixed ligand complexes CupHqArBs. A was glycylglycine or glycinamide, and B was ethylamine or 2-aminoethanol. The structure of CuH−1A2 in solution is discussed. It was found that the ligand A acts as a unidentate ligand and the other deprotonated H−1A as a terdentate one for the most part; only about 2% of this complex are in a bidentate-bidentate form.
  • Shuichiro Yamaguchi, Noboru Oyama, Kazuo Ikeda, Hiroaki Matsuda
    1981 Volume 54 Issue 12 Pages 3753-3758
    Published: 1981
    Released: June 02, 2006
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    The complex formation of the Cu(II) ion with ethylenediaminetetraacetic acid (EDTA) and N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA) has been studied potentiometrically and polarographically over the wide pH range from 1 to 11 in aqueous solutions containing 1.0 mol dm−1 NaClO4 at 25.0 °C. Both the emf data obtained by potentiometric titrations and the pH-dependence of reversible half-wave potentials were explained in terms of the formation of the following complex species: for the Cu–EDTA complexes, CuL2− (logβ101=17.28±0.04), CuHL (logβ111=20.15±0.04), CuH2L(logβ121=22.73±0.04), CuH3L+(logβ131=24.12±0.04), and CuH−1L3− (logβ1−11=6.83±0.05); for the Cu–HEDTA complexes, CuL (logβ101=16.30±0.05), CuHL (logβ111=18.76±0.04), CuH2L+ (logβ121=19.85±0.04) and CuHL−1L2− (logβ1−11=6.35±0.05), where βpqr=[CupHqLr]/[Cu2+]p[H+]g[L]r, and where L denotes the unprotonated molecule of EDTA or HEDTA.
  • Akimasa Yajima, Ryoko Matsuzaki, Motonori Eguchi, Yuzo Saeki
    1981 Volume 54 Issue 12 Pages 3759-3762
    Published: 1981
    Released: June 02, 2006
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    The reaction products obtained by heating a mixture of MoO3 and carbon in a SO2 stream at various temperatures were examined. The possible reactions during the above process were also studied. Further, thermodynamical consideration was made of the formation of MoS2. When a mixture of MoO3 and carbon was heated in a SO2 stream, MoO2 was formed above 400 °C. At 500–550 °C, the formation of a small amount of Mo4O11was also observed. Above 700 °C, the formation of MoS2 in addition to MoO2 was observed, and MoS2 alone was obtained at 1000 °C. Sulfur was obtained outside the heating zone throughout the temperature range in this experiment. The process of the formation of MoS2 by the reaction between MoO3 and SO2 in the presence of carbon can be represented as follows: The reaction between carbon and SO2 occurs at first to form sulfur. Above ca. 400 °C, the reductions of MoO3 with carbon and with sulfur occur to form MoO2. Above ca. 700 °C, MoS2 is formed by the reaction between MoO2 and sulfur, which are formed by the above reactions.
  • Kazumasa Ueda, Yasushi Kiyota, Yoshikazu Yamamoto
    1981 Volume 54 Issue 12 Pages 3763-3767
    Published: 1981
    Released: June 02, 2006
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    Thiazolylazo compounds react with iron(II) to form brownish complexes, which show a characteristic absorption in near-infrared region. These compounds possess the hydroxyl group in the o-position next to the azo group. Among them, iron(II)-2-(2-thiazolylazo)-5-dimethylaminophenol complex has the absorption maximum at 760 nm in chloroform; the optimum pH for iron extraction lies between 8.2–10.0. Beer’s law holds up to 2.0 μg cm−3 of iron and the molar absorption coefficient is 2.70×104 dm3 mol−1 cm1. The composition and the extraction constant of the complex are estimated to be Fe: TAM=1 : 2 and logKex=−4.20±0.04, respectively. Since the present method utilizes the specific absorption of the iron(II)-TAM complex, the presence of many ions is tolerable, especially of 3d type metals. The method was applied to the determination of traces of iron dissolved in river and sea waters with satisfactory results.
  • Yasuhisa Ikeda, Sumio Soya, Hiroshi Tomiyasu, Hiroshi Fukutomi
    1981 Volume 54 Issue 12 Pages 3768-3772
    Published: 1981
    Released: June 02, 2006
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    The kinetics of ligand substitution reactions in trimalonatovanadium(III), V(mal)33−, with various multidentate ligands, malonate (MAL), ethylenediaminetetraacetate (EDTA), and nitrilotriacetate (NTA) have been studied. The rate constant of the malonate exchange in V(mal)33− was obtained from the NMR line-broadening method to be kex=50 s−1 at 70 °C. The rate of EDTA substitution depends on the entering EDTA species. The values of second order rate constants are k21=0.04 M−1 s−1 (1 M=l mol dm−3) for H2edta as an entering ligand and k22=0.25 M−1 s−1 for H3edta at 25 °C. The NTA substitution is reversible under the experimental conditions studied. The apparent rate constants of the forward and backward reactions are k3=1.3×10−2 M−1 s−1 and k−3=2.0×103 M−1 s−1 at pH 3.5 and 25 °C, respectively. The univalent H2nta is found to be the only entering ligand.
  • Akira Odani, Osamu Yamauchi
    1981 Volume 54 Issue 12 Pages 3773-3779
    Published: 1981
    Released: June 02, 2006
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    Histidinate(His)-containing ternary α-amino acid-palladium(II) complexes have been studied by synthetic and spectroscopic methods. The following complexes with imidazolate (im), L- and D-His, L-asparaginate (L-Asn), and L-glutaminate (L-Gln) have been isolated as crystals: [Pd(im)2]·0.5H2O; [Pd(L-His) (D-His)]·H2O; [Pd(L-Asn)-(L-His)]·2H2O; [Pd(L-Gln) (L-His)]·2H2O. The ternary systems involving palladium (II), L-His, and an amino acid L-AA with an OH or a CONH2 group (AA=Asn, Gln, serinate, threoninate, or homoserinate) exhibit absorption maxima at 300–311 nm with ε 310–440 and negative and positive circular dichroism (CD) peaks at 307–328 nm and ≈300 nm, respectively. 13C and 1H NMR spectra gave the amounts of the cis and trans isomers of Pd(His)-(AA) in solution and confirmed that Pd(His)(AA) has an N3O donor set in the coordination plane. Whereas the CD magnitude additivity holds for the ternary systems Pd (L-His)(B) with B=glycinate, L-alaninate, or L-valinate and the systems with L-histidine methyl ester (L-HisOMe) and L-AA, Pd(L-HisOMe)(L-AA), the magnitudes for Pd (L-His) (L-AA) deviate significantly from those estimated on the basis of the additivity. The CD magnitude anomaly as well as the geometrical and rotational isomer populations calculated from the 1H NMR spectra establishes the existence of the ligand-ligand interaction between the carboxylato group of His and the hydroxyl or amido group of AA in solution.
  • Kazuaki Yamanari, Shigeru Naito, Yoichi Shimura
    1981 Volume 54 Issue 12 Pages 3780-3784
    Published: 1981
    Released: June 02, 2006
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    The binary and ternary solubility phase diagrams of the racemic and optically active complexes, [Co(val)(NH3)4]X2 and [Co(leu)(NH3)4]X2 (X=(1/2)SO42−, Cl, Br, and I), were determined in water. Spontaneous resolution was found for [Co(DL-val)(NH3)4]X2 (X=Cl and Br) at 5–55 °C and for [Co(DL-leu)(NH3)4]SO4 at 30–55 °C, the latter of which has been shown to crystallize as both a racemic compound (below 30 °C) and a conglomerate (above 30 °C).
  • Toru Sugiyama, Toshikazu Furihata, Kyoko Takagi, Michitsugu Sato, Shin ...
    1981 Volume 54 Issue 12 Pages 3785-3789
    Published: 1981
    Released: June 02, 2006
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    UV-irradiation of methyl 2-pyridinecarboxylate in methanol in the absence of added acid brings about methylation at the 5-position via the excitation of C=O of the ester group, while in the presence of added acid the 4-position of the pyridine ring is methylated. In the presence of sulfuric acid methoxylation via an excimer is dominant over methylation. In the presence of hydrochloric acid methylation via chlorine atoms becomes dominant.
  • Nobuo Okabe, Mariko Okamura, Ryoji Tokuoka, Ken-ichi Tomita
    1981 Volume 54 Issue 12 Pages 3790-3793
    Published: 1981
    Released: June 02, 2006
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    The interaction between α-helical poly-L-lysine (poly(L-Lys)) and the thyroid hormone, L-thyroxine (L-T4), was investigated at pH 11 by means of circular dichroism (CD) measurements in the wavelength region of 200–380 nm. At least four CD bands were induced near 235, 250, 290, and 343 nm. This indicates that these induced Cotton effects occurred as the result of the binding of L-T4 to poly(L-Lys), probably due to the electrostatic interaction. The wavelengths of the induced GD bands corresponded to those of the UV absorption bands of L-T4 in the poly(L-Lys) : L-T4 mixture, although small red-shifts of the CD bands were observed at the shortest and the longest wavelengths (235 nm and 343 nm). These CD bands might be interpreted by the fixed intramolecular orientation around an asymmetric α-carbon atom of the bound L-T4 or by the intermolecular interaction between the peptide backbone of poly(L-Lys) and the bound L-T4.
  • Ichiro Okura, Satoshi Nakamura, Masatoshi Kobayashi
    1981 Volume 54 Issue 12 Pages 3794-3798
    Published: 1981
    Released: June 02, 2006
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    The bovine serum albumin coordinated Fe4S4-cluster, which had hydrogenase activity, was synthesized. Its physical and chemical characteristics were then compared with those of natural hydrogenase. Though the affinities of hydrogenase and the albumin-coordinated Fe4S4-cluster for the substrate, methyl viologen, were similar, the hydrogenase activity for hydrogen evolution was 105 times greater than the cluster. Two types of Fe4S4-clusters, coordinated by the fragments of the cleaved albumin obtained by treatment with cyanogen bromide, were synthesized, and their hydrogenase activities were compared. The activity with the iron-sulfur cluster incorporated in the fragment with MW 40000 was much higher than that of the one incorporated in the fragment with MW 20000. The amino acid arrangement to form the active site was discussed on the analogy of the other iron-sulfur proteins.
  • Tamon Okano, Teruyuki Kobayashi, Hisatoshi Konishi, Jitsuo Kiji
    1981 Volume 54 Issue 12 Pages 3799-3805
    Published: 1981
    Released: June 02, 2006
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    The hydrogenation of methyl crotonate with CO and H2O is efficiently catalyzed by RhH2(O2COH)[P(i-Pr)3]2 or [RhCl(C7H8)]2/P(i-Pr)3/n-BuLi (C7H8=norbornadiene). Both catalyst precursors are shown to form the same active species; transRh(OH)(CO)[P(i-Pr)3]2. The catalytic activity of the system ([RhCl(C7H8)]2/phosphine/n-BuLi) increases with increase of the basicity of the phosphine ligands (phosphine=P(i-Pr)3>P(n-Bu)3>PPh(i-Pr)2>PPh2(i-Pr)>PPh3). This reaction is also applicable to the hydrogenation of the C=C bond of electronwithdrawing olefins and the C=O bond of ketones and aldehydes. Interestingly, the catalysis for the C=C bond, to which less electron-withdrawing groups are attached, gives dominantly aldehydes due to hydroformylation. The mechanism is also discussed.
  • Kazunari Hashizume, Yasutsugu Shimonishi
    1981 Volume 54 Issue 12 Pages 3806-3810
    Published: 1981
    Released: June 02, 2006
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    Side-products are formed when Ac–Trp–OMe, Ac–Gly–Trp–OMe, or Ac–Trp–Trp–OMe is stored in trifluoroacetic acid. Two products from each of Ac–Trp–OMe and Ac–Gly–Trp–OMe and one product from Ac–Trp–Trp–OMe are isolated by the column chromatography on silica gel and confirmed for homogeneity by the highperformance liquid chromatography. As confirmed by 1H-NMR and mass spectral analyses, they have dimerized structures through the α-carbon to α′-carbon binding of two indole rings. One of the two products from each of Ac–Trp–OMe and Ac–Gly–Trp–OMe is the trans-isomer(s) and the other the cis-isomer(s). Only a trans-isomer(s) is obtained from Ac–Trp–Trp–OMe.
  • Chung-gi Shin, Yasuchika Yonezawa, Kazuhiro Watanabe, Juji Yoshimura
    1981 Volume 54 Issue 12 Pages 3811-3814
    Published: 1981
    Released: June 02, 2006
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    The reaction of ethyl 2-azido-2-alkenoate with organic tervalent phosphorus reagent gave the corresponding 2-phosphoranylideneamino derivative as an stable intermediate. This transformed gradually at room temperature, or immediately on a silica-gel column to give the corresponding 2-phosphinylamino derivative in a good yield. The Arbusov reaction of the intermediate which occurred during the transformation was found to be applicable for the other azido olefins. The formation mechanism and the configurational determination of the new products are discussed.
  • Mitsuo Sekine, Ken Hamaoki, Tsujiaki Hata
    1981 Volume 54 Issue 12 Pages 3815-3827
    Published: 1981
    Released: June 02, 2006
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    Appropriately protected or unprotected S,S-diphenyl thymidine 3′- or 5′-phosphorodithioates and S,S-bis(4-methoxyphenyl) thymidine 3′- or 5′-phosphorodithioates were successfully prepared by the reaction of the thymidine derivatives with cyclohexylammonium S,S-diaryl phosphorodithioates in the presence of 2,4,6-triisopropylbenzene-sulfonyl chloride (TPS). Stabilities of the thymidylic compounds under acidic or alkaline conditions were described in detail. Several methods for the deprotection of one or both arylthio groups under neutral conditions were also described in connection with the synthesis of oligothymidylates. By the use of the bis(4-methoxyphenylthio)phosphoryl group, di- and tri-thymidylates were synthesized in high yields.
  • Masayuki Kanishi, Jun-ichi Kunizaki, Junji Inanaga, Masaru Yamaguchi
    1981 Volume 54 Issue 12 Pages 3828-3831
    Published: 1981
    Released: June 02, 2006
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    A series of new macrocyclic cyclophane polylactones has been synthesized by one-step condensation of the appropriate tri(acid chloride)s and triols using the silver cyanide-promoted esterification procedure.
  • Hiromi Kikuchi, Shiro Hatakeyama, Gaku Yamamoto, Michinori Oki
    1981 Volume 54 Issue 12 Pages 3832-3836
    Published: 1981
    Released: June 02, 2006
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    9-(1-Methyl-2-propenyl)triptycenes were prepared by addition of substituted benzynes to 9-(1-methyl-2-propenyl) anthracene or Dields-Alder addition of p-benzoquinone to the anthracene followed by enolization and methylation. The crystals of these compounds were pure or enriched isomers of the possible rotamers but the rotational barriers were too low to obtain every possible isomer in a pure state at room temperature. The barriers to rotation were obtained by both classical and dynamic NMR methods. These values were almost the same when the peri-substituent was either a chloro or a bromo but were definitely lower when the peri-substituent was a methyl or a methoxyl.
  • Akihiro Tanaka, Azuma Watanabe, Reiko Kobayashi, Tsutomu Tsuchiya, Sum ...
    1981 Volume 54 Issue 12 Pages 3837-3845
    Published: 1981
    Released: June 02, 2006
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    Mycaminosyltylonolide diethyl acetal was, after reduction of the 9-keto group, hydrolyzed, and the seco-acids obtained were recyclized to give new 16-membered (9R)- and (9S)-hydroxy macrolide derivatives, in which the 23-hydroxyl group of the starting substance was incorporated into the macrolactone ring. Selective oxidation of the (9S)-hydroxy derivative (15) with DDQ gave the keto compound (18). Removal of the acetal-protecting groups gave a new macrolide (19), which is antibacterial. Several other O-acetyl derivatives were also prepared and their antibacterial activities were measured. By the 1H- and 13C-NMR spectroscopies of 3,23-di-O-acetylmycaminosyltylonolide diethyl acetal by varying the temperature, the presence of two rotamers was clarified.
  • Keizo Ogino, Hitoshi Yamauchi, Yoshinori Ueno
    1981 Volume 54 Issue 12 Pages 3846-3849
    Published: 1981
    Released: June 02, 2006
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    The behavior of natural surfactants was studied at an oil-water interface by measurement of the interfacial tension and the observation of the oil-water interface. Lecithin was used as an oil-soluble substance and sodium cholate was used as a water-soluble substance; n-paraffin, corn oil, unsaturated fatty acid and fatty alcohol were used as an oil phase. The reduction of interfacial tension was greatest in a dodecane-sodium cholate solution system, but the minimum interfacial tension was observed in an oleic acid-sodium cholate solution system. Spontaneous emulsification occurred in the oil phase when oleic acid was left in contact with sodium cholate solution. The most remarkable change was found in the system of oleic acid in contact with sodium cholate solution, in which crystal of cholic acid were formed at the interface.
  • Hiroshi Miyazaki, Yoshio Matsuhisa, Tanekazu Kubota
    1981 Volume 54 Issue 12 Pages 3850-3853
    Published: 1981
    Released: June 02, 2006
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    Cyclic voltammograms of aromatic amine N-oxides were recorded in nonaqueous solvents at various sweep rates less than 10 V/s. The measurement was carried out for both cathodic and anodic sweeps, and the sweep rate for obtaining a good cyclic voltammogram was correlated with the wave height of the a.c. polarogram in the reduction and oxidation processes, respectively. A good correlation was found between the sweep rate and the wave height in both the reduction and oxidation processes. This confirmed that the two values serve as good measures of the stability of the anion or cation free radical produced by the electrode reaction of the aromatic amine N-oxides. The data were also examined by comparison with results from an electron spin resonance study. Finally, the temperature effect on the cyclic voltammogram of pyridine N-oxide was investigated in detail.
  • Toyoaki Kimura, Naoyuki Ogawa, Kenji Fueki
    1981 Volume 54 Issue 12 Pages 3854-3856
    Published: 1981
    Released: June 02, 2006
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    An optical absorption study was made on trapped electrons in γ-irradiated 3-methylhexane-2,2,4-trimethylpentane-2,2-dimethylbutane glasses at 77 K. The absorption maximum of trapped electron spectra shifts to longer wavelengths and the trapped electron yield decreases with decreasing 3-methylhexane concentration. The observed spectral shifts were interpreted through a semicontinuum model calculation.
  • Ikuo Abe, Katsumi Hayashi, Mutsuo Kitagawa
    1981 Volume 54 Issue 12 Pages 3857-3858
    Published: 1981
    Released: June 02, 2006
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    In order to predict the adsorbability of organic compounds out of water onto activated carbon, the contribution of individual atoms to the adsorbability is calculated. The contribution of the carbon atom is positive, that of nitrogen and oxygen atoms is negative, and that of the hydrogen atom is very small.
  • Kiwamu Yamaoka, Takumi Matsuda, Tsuyoshi Murakami
    1981 Volume 54 Issue 12 Pages 3859-3860
    Published: 1981
    Released: June 02, 2006
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    Interactions between nitroxide spin-labeled dyes (Acridine Orange, Proflavine, and 9-aminoacridinium chloride) and poly(p-styrenesulfonate), polyphosphate, and polyacrylate were studied by measuring visible absorption spectra in aqueous solutions. The bound-dye spectra and equilibrium constants were determined by the principal-component-analysis method. The metachromatic behavior of dye-polymer complexes was clarified.
  • Masao Sekizaki
    1981 Volume 54 Issue 12 Pages 3861-3862
    Published: 1981
    Released: June 02, 2006
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    The crystals are triclinic, P\bar1. R is 0.047 for 1617 independent non-zero reflections. The complex has a centrosymmetric square-planar coordination, with two imino nitrogen and two bromine atoms in trans positions.
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