Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 50 , Issue 12
Showing 1-50 articles out of 76 articles from the selected issue
  • Tooru Taga, Yoshihiro Kuroda, Kenji Osaki
    1977 Volume 50 Issue 12 Pages 3079-3083
    Published: 1977
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    The crystal structure of potassium D-glucarate was determined by X-ray analysis. The conformation of the glucaric anion in the potassium salt differs from that of the dianion in the crystal of the calcium salt. The proton magnetic resonance spectra of the solutions of the potassium salt and the calcium salt show that the glucarate solution is an equilibrium mixture of the two conformers observed in the crystals. Studies on the induced shifts by adding europium nitrate to the acidic solution indicate that the europium ions are selectively bound to the potassium type conformer. Calcium sequestant by the glucaric acid in alkaline solutions should occur when calcium ions bind the calcium type conformers in a dianionic state.
  • Hideo Shikata
    1977 Volume 50 Issue 12 Pages 3084-3089
    Published: 1977
    Released: April 19, 2006
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    ENDOR enhancement is phenomenologically described, applying the method of Lloyde and Pake. Emphasis is placed on the effect of incomplete hf separation. It is shown that fractional ENDOR enhancement can approximately be expressed as the product of that which Freed has formulated when the effect is absent, and an modified Allendoerfer-Maki type correlation, T2e2Δω2⁄(c+T2e2Δω2), where c is a constant dependent on the microwave power. Also, a simplified method is proposed for calculating the fractional ENDOR enhancement for a multilevel system consisting of several sets of equivalent protons, when Wn<<We, and it is proven that the week rf power irradiated leads to an ENDOR enhancement proportional to the number of equivalent protons, in the absence of the effect of incomplete hf separation.
  • Hideo Shikata, Kazuhiko Ishizu
    1977 Volume 50 Issue 12 Pages 3090-3095
    Published: 1977
    Released: April 19, 2006
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    The ratio of the ENDOR enhancement to the ESR intensity (E) of galvinoxyl in toluene was measured under various conditions of microwave power, rf power and temperature. The results are discussed in comparison with a phenomenological theory in part I. It is proven that the apparent longitudinal electron spin relaxation time for a t-butyl proton under NMR excitation is about twice as long as those for methylidyne and ring protons, which is explained by the effect of incomplete hf separation. Also, it is shown that the reciprocal of the slope of the plot of E−1 vs. (rf power)−1 for methylidyne and ring protons is approximately proportional to the number of equivalent protons, whereas that for a t-butyl proton can be explained only if the effect of incomplete hf separation is taken into consideration. The value of b=WnWe for methylidyne and ring protons, simulated from the temperature dependence of E based on a previous theory, can be closely correlated to the spin distribution in galvinoxyl.
  • Tetsutaro Yoshinaga, Hiroshi Hiratsuka, Yoshie Tanizaki
    1977 Volume 50 Issue 12 Pages 3096-3102
    Published: 1977
    Released: April 19, 2006
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    Vibronic π-π* transition bands of pyrene, 4,5-dihydropyrene (DHP), and 4,5,9,10-tetrahydropyrene (THP) were assigned by means of dichroism analysis using stretched poly(vinyl alcohol) films. The absorption spectra of the samples in the non-stretched films were divided into two component spectra polarized along the long (x) and short (z) axes of the molecular plane. For pyrene, in addition to the four conventionally-assigned band systems (1Lb, 1La, 1Bb, and 1Ba), some forbidden bands were found in the respective band regions. Most of the vibronic DHP and THP bands were also reasonably well assigned from comparisons with the calculated results for phenanthrene and biphenyl, respectively.
  • Hiroko Hoshino, Susumu Tajima, Fusako Isogai, Toshikazu Tsuchiya
    1977 Volume 50 Issue 12 Pages 3103-3106
    Published: 1977
    Released: April 19, 2006
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    The mass spectra of 1-alkenes ranging from C5 to C10 were measured at temperatures of the ion source 120–250 °C. Fragmentation M+\oversetm28→(M–28)+ and M+\oversetm28→(M–29)+, where m28 and m29 denote the metastable peaks of the fragmentations, were studied. The behavior of the curve of the intensity ratios R28=m28F28 and R29=m29F29(F28 and F29 denote the intensities of the (M–28)+ ion and the (M–29)+ ions, respectively), versus temperature T of the ion source of the mass spectrometer is explained by the quasi-equilibrium theory (QET).
  • Masayuki Aizawa, Tsuyoshi Komatsu, Tsurutaro Nakagawa
    1977 Volume 50 Issue 12 Pages 3107-3110
    Published: 1977
    Released: April 19, 2006
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    Poly(2-vinylpyridine) partially quaternized with 1-dodecylbromide, a “polysoap,” sodium dodecyl sulfate (SDS), and dodecylpyridinium bromide (DPBr) in their micellar solutions were investigated by the spin-probe technique. It was found that the alkyl side chains in polysoap micelles associate more rigidly than in low-molecular surfactant micelles. This fact is attributed to the surface active groups covalently connected to long polymer chains in the polysoap molecule. By a recently developed method, the rotational correlation times of 2,2,6,6-tetramethyl-4-benzoyloxypiperidin-1-oxyl radical in SDS and DPBr micelles were found to be 5.9×10−10 and 3.5×10−10 s/rad, respectively. From the values of the isotropic hyperfine splitting constants, it was estimated that the DPBr micelle solubilizes the probe molecule at a more inner site of the hydrophobic portion than does the SDS micelle.
  • Tsuneo Fujii, Satoshi Suzuki
    1977 Volume 50 Issue 12 Pages 3111-3117
    Published: 1977
    Released: April 19, 2006
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    Molecular orbital analysis, which is an application of configuration analysis proposed by Baba et al., has been applied to the interpretation of the photoelectron spectra of substituted naphthalenes, with particular attention paid to the dependence of the spectra on the position of substitution and on the character of the substituents. The results of MO calculations based on the Pariser-Parr-Pople method have been analyzed in terms of the π-MO’s of naphthalene and the π-AO or π-MO’s of a substituent. The results of the molecular orbital analysis for naphthalene derivatives with an electron-donating group are compared with the results for those with an electron-accepting group.
  • Yoshihiro Kuroda
    1977 Volume 50 Issue 12 Pages 3118-3123
    Published: 1977
    Released: April 19, 2006
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    The nuclear magnetic multiple-resonance method developed by Forsén and Hoffman for the study of exchange rates has been applied to the two different types of OH protons of the 1,3-dihydroxyacetone dimer in dimethyl-d6 sulfoxide, i.e., OH (α) and CH2OH (β). Here, “decay” and “recovery” curves were obtained using the so-called “INDOR” method, instead of a rapid repetitive scan method. Since the INDOR method continuously monitors a peak height, decay and recovery curves as fast as 1 s can be drawn by storing them in a computer after a single scan. The concentration dependence was examined as a two-site exchange system by neglecting the small amount of water (γ) contained in the dimethyl sulfoxide solvent. Both the lifetime, τ, and the longitudinal relaxation time, T1 obtained from this assumption correlate well with the concentration variation of the 1,3-dihydroxyacetone dimer. The difference in the types of OH protons on the concentration dependence is clearly seen for the latter parameter, T1. From the triple-resonance experiments including γ, it was found that the β proton is more “labile” than the α.
  • Takahisa Doba, Tsuneki Ichikawa, Hiroshi Yoshida
    1977 Volume 50 Issue 12 Pages 3124-3126
    Published: 1977
    Released: April 19, 2006
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    Pentamethylnitrosobenzene synthesized readily from pentamethylbenzene was studied for utilization in a spin-trapping technique. In a benzene solution it forms a dimer with a dissociation constant of 105.26exp(−50⁄RT) in units of kJ/mol. It traps the t-butyl radical with the trapping rate constant of 1.4×108 mol−1 dm3 s−1 at 299 K. It is thus an efficient spin-trapping agent, even though only a fraction of it is reactive with the short-lived free radicals because the equilibrium lies more on the side of the dimeric form. Electron spin resonance parameters were determined for the spin-adduct radicals derived from alkyl, alkoxyl, and phenyl radicals with this trapping agent. These free radicals were found to attach exclusively to the nitrogen atom of the nitroso compound.
  • Hayao Kobayashi, Keiji Kobayashi
    1977 Volume 50 Issue 12 Pages 3127-3130
    Published: 1977
    Released: April 19, 2006
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    The organic conductor, (TTF) (SCN)0.57, is a quasi-one-dimensional non-stoichiometric compound, which crystallizes in a tetragonal system having a P42/mnm space group. The lattice constants are a=11.154 (3) and c=3.607 (2) Å. TTF molecules form segregate eclipsed stacks with thiocyanate ions occupying the channels between the stacks. The intermolecular distance between adjacent TTF molecules is 3.607 Å. The room-temperature electrical conductivity is 85–310 (Ω cm)−1. A series of resistance jumps are observed in the temperature-dependent resistivity curves.
  • Shizuo Fujiwara, Grazyna Formicka-Kozlowska, Henryk Kozlowski
    1977 Volume 50 Issue 12 Pages 3131-3135
    Published: 1977
    Released: April 19, 2006
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    Proton NMR spectra of glutathione have been analyzed over the whole pH region. The spectra of the glutamic acid residue are of the ABCDX type at pHs below 2.5, of the AA′BB′X types in the pH region 2.5–9, and of the ABCC′X type at pHs higher than 9. For the cysteine part, spectra of the ABC type have been observed at pHs higher than 8, which change to spectra of the A2B type at pHs lower than 7. On the basis of these results the conformation of the glutathione molecule in solution has been discussed in detail.
  • Tsutomu Okuda, Koji Yamada, Hideta Ishihara, Hisao Negita
    1977 Volume 50 Issue 12 Pages 3136-3139
    Published: 1977
    Released: April 19, 2006
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    The quadrupole coupling constants (e2Qqh) and the principal axes of electric field gradient (efg) at 81Br, 127I, 27Al, 121Sb, and 209Bi in AlBr3·SbBr3, AlI3·SbI3, and AlBr3·BiBr3 were determined by means of NQR or NMR, in order to clarify the structures and chemical bonds of these compounds. The NQR spectra of AlBr3·SbBr3 and AlI3·SbI3 resemble each other and these two compounds consist of V-shaped SbX2+ and distorted tetrahedral AlX4 ions (X=Br and I). However, there are weak bonds between the Sb atom in SbX2+ and the halogens in AlX4 ion. The V-shaped SbX2+ has the bond angle 97.3° for the bromide and 99.0° for the iodide. The orientation of the efg axes at the 121Sb atom suggests that the antimony atom has a lone pair of electrons in the opposite direction to the bisector of the two Sb–X bonds. On the other hand, only one terminal bromine atom bonded to the Bi atom was found for AlBr3·BiBr3.
  • Tsuneyuki Minegishi, Toshihiko Hoshi, Hiroshi Hiratsuka, Yoshie Taniza ...
    1977 Volume 50 Issue 12 Pages 3140-3143
    Published: 1977
    Released: April 19, 2006
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    The polarized absorption sepctra of xanthene and xanthone were measured in stretched poly (vinyl alcohol) films, and the polarization direction of each electronic transition was determined. It was confirmed that xanthone has the short molecular-axis polarized bands (1A11A1) at 343, 260, and 226 nm, and the long molecular-axis polarized ones (1BA21A1) at 290, 266, and 242 nm. The electronic transitions of xanthone are discussed in connection with those of xanthene by use of the configuration analysis. For the 266 and 260 nm bands, the contributions of the intramolecular charge transfer character from the xanthene skeleton to the carbonyl group are considerable.
  • Minoru Sasaki, Tatsuya Yasunaga, Shigemi Satake, Minoru Ashida
    1977 Volume 50 Issue 12 Pages 3144-3148
    Published: 1977
    Released: April 19, 2006
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    The frequency dependence of the damping coefficient of a capillary wave was measured in decylamine hydrochloride solutions. The observed relaxations were well expressed by the double-relaxation equations. From the concentration dependence of the relaxation parameters obtained, the relaxations at low and high frequencies were attributed to the adsorption-desorption and ion-pair formation reactions on the surface, respectively. Furthermore, the adsorption rate constants are related to the hydrophobic and hydrophilic properties of the surfactants.
  • Kiyotane Sekido, Haruaki Ono, Teruo Noguchi, Sakutaro Hirokawa
    1977 Volume 50 Issue 12 Pages 3149-3152
    Published: 1977
    Released: April 19, 2006
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    The crystal structure of α-form of 2,4,6-trimethyl-1,3,5-trithiane (α-TTA) has been determined by the X-ray method. The crystal data are a=9.768, b=12.306, c=8.521 Å, and β=116.33 °. The space group is Cc with four molecules in a unit cell. The structure was deduced from interpretation of the 3D-Patterson series, and refined by 3D-Fourier and least-squares method to the final R factor of 0.040 for 1371 reflections. The molecule has a six-membered ring where three sulfur atoms and three carbon atoms are linked alternatively, forming a chairform. Two methyl groups are in the equatorial positions and one methyl group in the axial. The mean values of the bond distances are 1.818 Å for S–C and 1.519 Å for C–Ceq. The distance is 1.541 Å for C–Cax. The mean values of the bond angles are 101.89° for C–S–C, 107.60° for S–C–Ceq, 113.25° for S–C–Cax, and 112.92° for S–C–S.
  • Susumu Yoshimura, Mutsuaki Murakami
    1977 Volume 50 Issue 12 Pages 3153-3157
    Published: 1977
    Released: April 19, 2006
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    Solid-state anodic oxidation of aluminum contacted to a pellet of various organic conductors based on 7,7,8,8-tetracyanoquinodimethane was observed. A typical passivation curve was observed in the current-voltage characteristics for the anodic polarization of the metal. Along with impedance measurements on the electrode system, it was proved that the passivation is due partly to a thermal transformation in the organic conductor and partly to a solid-state anodization of aluminum, the latter being conditioned by the former through the formation of an electrolyte layer in situ. The current efficiency of anodization was estimated by a linear voltage sweep method to be as high as 2%, depending on the ambient moisture. The high efficiency explains the prominent self-healing action of a new type of solid electrolytic capacitor in which manganese dioxide is replaced by an organic-conductor counterelectrode.
  • Takahisa Doba, Tsuneki Ichikawa, Hiroshi Yoshida
    1977 Volume 50 Issue 12 Pages 3158-3163
    Published: 1977
    Released: April 19, 2006
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    The photochemical reaction of 2-methyl-2-nitrosopropane (a spin-trapping agent) in benzene was studied at 299 K by monitoring the optical absorption intensity of the spin-trapping agent and the ESR signal intensity of the spin-adduct radical (di-t-butyl nitroxide). The observed kinetic feature was interpreted in terms of three elementary processes; the photodissociation of the spin-trapping agent giving a t-butyl radical, the spin trapping of the t-butyl radical by the trapping agent giving the spin adduct radical, and the reaction of the spin-adduct radical with the t-butyl radical giving diamagnetic products. The rate constant of the last process was found to be 10 times as large as that of the spin-trapping process, which was determined to be 3.3×106 mol−1 dm3 s−1 based on the reported rate constant for the scavenging of the t-butyl radical by tributylstannane. The relative spin-trapping rate constants toward the t-butyl radical were also determined to be 0.07, 1.0, 41, 63, and much higher than 50 for 2,4,6-tri-t-butylnitrosobenzene, 2-methyl-2-nitrosopropane, pentamethylnitrosobenzene, nitrosodurene and nitrosobenzene, respectively. C-phenyl-N-t-butylnitrone was found to be much less reactive by a factor of less than 0.003.
  • Fumiyuki Mitsumori, Yoji Arata, Shizuo Fujiwara, Masaharu Muranaka, Yo ...
    1977 Volume 50 Issue 12 Pages 3164-3166
    Published: 1977
    Released: April 19, 2006
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    The spontaneous degradation of penicillin G in aqueous solution has been studied using NMR and thin layer chromatography. Correlation NMR spectroscopy was used to follow products which appear at the early stage of degradation. It has been found that in 0.3 M phosphate buffer (pH 7.0, 30 °C) a successive first order degradation
    penicillin G \xrightarrowk1 penicilloic acid \xrightarrowk2 secondary product
    is dominant with kinetic constants of k1=0.7×10−2 h−1 and k2=6×10−2 h−1.
  • Katsuki Kitahama, Hideko Kiriyama
    1977 Volume 50 Issue 12 Pages 3167-3176
    Published: 1977
    Released: April 19, 2006
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    The neutron-diffraction results for deuterated single crystals have shown definitely that the phase transition is ascribable to the ordering of the hydrogen atoms. The ordered arrangement below the transition temperature (Tt=234 K) agrees well with the NMR results. No doubling of the unit cell or loss of the center of symmetry can be detected. In the disordered phase above Tt, four deuterons of two non-equivalent water molecules are distributed into seven sites. The occupancy factors of the individual sites have been refined by least-squares methods under different constraints. Bernal and Fowler’s ice rule is obeyed in the H-bonded water layers, and the water molecules of crystallization scarcely dissociate at all. The crystal structure has been redetermined by the X-ray diffraction method at 209 and 223 K, using an SnCl2·2H2O single crystal. No distinct change in the structure of non-hydrogen atoms has been disclosed on passing through the transition point (Tt=218 K). However, in the close vicinity of Tt, the a and c lattice parameters and the three H-bonded O···O distances steeply change in association with the ordering of the hydrogen atoms.
  • Akio Takenaka, Yoshio Sasada, Keiji Yamamoto, Jiro Tsuji
    1977 Volume 50 Issue 12 Pages 3177-3181
    Published: 1977
    Released: April 19, 2006
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    The crystal structure of dichloro[N, N-dimethyl-α-methyl-o-(butylphenylphosphino)benzylamine]palladium-(II) has been determined from MoKα diffraction data. The space group is P21 with Z=2, a=9.255(2), b=14.372 (3), c=8.584(1) Å, and β=105.99(1)°. The final R became 0.034 by least-squares refinement. The Pd atom has a square planar coordination of N, P, and two Cl atoms, which is considerably distorted by the intramolecular atomic repulsions. The Pd–N distance, 2.134(4) Å, which is longer than those found so far, is accompanied by a short distance 2.285(1) Å of trans Pd–Cl. A plot of Pd–Cl distance versus trans Pd–N distance in several Pd complexes, in which the nitrogen atom is not π-acceptor, shows a linear relationship with the correlation factor of −0.28(4).
  • Hachiro Nakanishi, Yoshio Sasada
    1977 Volume 50 Issue 12 Pages 3182-3185
    Published: 1977
    Released: April 19, 2006
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    Photooligomerizable crystals of dimethyl m-phenylenediacrylate are orthorhombic, Pmn21, with a=26.419(8), b=3.960(1), c=5.935(2) Å, and Z=2. The structure was solved by the direct method and refined by the block-diagonal least-squares calculation to the R value of 0.042 for 617 observed reflections. The molecule is nearly planar and V-shaped with a mirror symmetry. A parallel plane-to-plane stack is found along the short b-axis. The molecules in the stack overlap completely, in contrast with the half-molecule overlap in the photopolymerizable crystals of this kind. The length of the b-axis is just the shortest intermolecular distance between reactive double bonds, indicating that the double bonds related by the b-translation would react to form a cyclobutane ring with a mirror symmetry.
  • Hitoshi Nishizawa, Masahiko Shimada, Kiyoshi Matsuoka, Mitsue Koizumi
    1977 Volume 50 Issue 12 Pages 3186-3188
    Published: 1977
    Released: April 19, 2006
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    The garnet Mn3Fe2Si3O12 with a0=11.821 Å was synthesized at high pressure and temperature. Infrared and Mossbauer spectra of the synthetic garnets A3Fe2Si3O12 (A: Mn, Cd, Ca) suggest that the distortion of SiO4 tetrahedra in these garnets increases and that of FeO6 octahedra decreases with increase in the radius of eight fold coordinated cation.
  • Nobuo Yoshida, Nobuhiko Ishibashi
    1977 Volume 50 Issue 12 Pages 3189-3193
    Published: 1977
    Released: April 19, 2006
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    The selectivity of liquid anion exchange membranes consisting of a perchlorate, thiocyanate, or iodide salt of Crystal Violet dissolved in nitrobenzene was studied by measuring membrane potentials. In bi-ionic systems the selectivity coefficient was observed to vary with the concentrations of aqueous solutions and of the ion exchanger in the membrane. This was attributed mainly to the ionic composition at the membrane-solution interface differing from that in the bulk solution. However, when the concentration of the aqueous solutions was sufficiently high in comparison with that of the ion exchanger, a selectivity coefficient intrinsic to a pair of counter ions was obtained. This selectivity coefficient was also applicable to mixed electrolyte systems and was shown to be consistent with the Conti-Eisenman theory on the relation between the selectivity coefficient and ionic parameters.
  • Masashi Tanaka
    1977 Volume 50 Issue 12 Pages 3194-3198
    Published: 1977
    Released: April 19, 2006
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    The polarized reflection spectra of the crystals of the picric acid complexes with 1-methylnicotinamide, tryptamine, DL-tryptophan and serotonin have been measured from 15000 to 40000 cm−1 and the molar extinction coefficient of these crystals has been obtained by the Kramers-Kronig transformation. Furthermore, the theoretical calculation of the electronic states of these complexes has been made and compared with the experimental results. This analysis shows that the appearance of the new band in the region of 20000 cm−1 is the origin of the reddish color of the crystals of tryptamine picrate, DL-tryptophan picrate, and serotonin picrate; the new band can be assigned to the charge-transfer band from the picrate anion to the indole nucleus.
  • Mitsutaka Kitamura, Kazuo Sasaki, Hideo Imai
    1977 Volume 50 Issue 12 Pages 3199-3201
    Published: 1977
    Released: April 19, 2006
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    Acetylacetone was catalytically reduced in the course of the electrolytic reduction of bis(acetylacetonato)oxovanadium(IV) at a mercury cathode. In acetonitrile solutions the catalytic reduction proceeded at −2.1 V vs. Ag/0.01 mol dm−3 AgClO4 electrode and the reduction products were hydrogen and acetylacetonate anion, while by the direct electrolysis of acetylacetone at −2.5 V a product with vicinal hydroxyl groups was formed. A steady-state current was observed in the controlled potential electrolysis. A reaction mechanism involving the regeneration of trivalent vanadium by the coupled chemical reaction of divalent vanadium with acetylacetone is proposed.
  • Kousaburo Ohashi, Kumiko Yasu, Choutaro Suzuki, Katsumi Yamamoto
    1977 Volume 50 Issue 12 Pages 3202-3205
    Published: 1977
    Released: April 19, 2006
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    The spectrophotometric determination of trace amounts of phosphates, based on the color development of phosphomolybdenum blue formed by the reaction of phosphate with a mixture of molybdenum(V) (Mo2O42+) and molybdenum(VI), is described. The rates of formation of phosphomolybdenum blue were measured at 25°C in a perchloric acid medium. The maximum constant color development was obtained in the perchloricacid range from 0.20 to 0.41 M under given conditions by warming the solution for 10 min at 80°C. The method obeys Beer’s law in the phosphate-concentration range from 0.08 to 1.16 μg/ml. The molar absorptivity at 840 nm was calculated to be 2.4×104 1 mol−1 cm−1. The rate is inverse fifth-order with respect to the perchloric-acid concentration in the range from 0.20 to 0.41 M and is first-order with respect to the molybdenum(V) concentration. The formation rates increase with the phosphate and molybdenum(VI) concentrations, although the rate dependence on the concentrations of these reactants is complicated. The ratio of P: Mo(V) for phosphomolybdenum blue was determined to be 1 : 1 using the molar-ratio method.
  • Masao Sugawara, Yuh’ichi Rokugawa, Tomihito Kambara
    1977 Volume 50 Issue 12 Pages 3206-3208
    Published: 1977
    Released: April 19, 2006
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    A simple and sensitive spectrophotometric method for determination of copper(II) is described. It is based on the reaction of copper(II) with Hydroxynaphthol Blue in the weakly alkaline medium and the decomposition of the unconsumed reagent which shows an intense absorption at the wavelength, 555 nm, of the maximum absorbance of the copper(II) complex. Beer’s law is obeyed over the range 0.13–1.27 ppm copper with the molar absorption coefficient of ε555=3.01×104 dm3 mol−1 cm−1 (Sandell’s sensitivity 2.11×10−3 μg/cm2). A fairly large number of common ions except for nickel(II) do not interfere.
  • Miho Fujita, Yuzo Yoshikawa, Hideo Yamatera
    1977 Volume 50 Issue 12 Pages 3209-3215
    Published: 1977
    Released: April 19, 2006
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    All four possible isomers of the bis(ethylenediamine)sarcosinatocobalt(III) ion, [Co(sar) (en)2]2+, were separated chromatographically on the column of an SP-Sephadex cation exchanger, and their absorption, circular dichroism, and 13C NMR spectra were measured. The more stable pair of isomers were identified as Δ-[Co(S-sar) (en)2]2+ and Λ-[Co(R-sar) (en)2]2+, while the less stable pair were Δ-[Co(R-sar) (en)2]2+ and Λ-[Co(S-sar) (en)2]2+. The Δ-[Co(S-sar) (en)2]2+ isomer in an aqueous solution showed mutarotation which can be ascribed to a change in configuration (epimerization) about the sarcosinato nitrogen atom. In equiribrium at 25°C, the mixture consisted of 84.8% of the Δ(S) isomer and 15.2% of the Δ(R) isomer. From this result, the free-energy difference between the isomers was estimated to be 4.26 kJ mol−1. The presence of the less stable isomers, which were not found by Buckingham et al., was also confirmed by the 13C NMR measurements.
  • Masaaki Kojima, Masaru Iwagaki, Yuzo Yoshikawa, Junnosuke Fujita
    1977 Volume 50 Issue 12 Pages 3216-3221
    Published: 1977
    Released: April 19, 2006
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    Seven new cobalt(III) complexes containing N-methylbis(2-aminoethyl)amine (4-methyldiethylenetriamine, abbreviated as dema) were prepared and their structures were determined by electronic, circular dichroism, and PMR spectroscopy. For the mixed [Co(dien) (dema)]3+ complex (dien=diethylenetriamine), three geometric isomers, s-fac, u-fac, and mer were isolated. The [Co(dema)2]3+ complex formed only s-fac isomer. A conformational analysis was carried out to compare the stability of these geometric isomers.
  • Yoshitane Kojima, Ken Hirotsu, Keiji Matsumoto
    1977 Volume 50 Issue 12 Pages 3222-3231
    Published: 1977
    Released: April 19, 2006
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    The crystal structure of the title compound has been determined by a three-dimensional X-ray structure analysis, using 4563 counter intensity data. The crystals are monoclinic, with a=22.97(2), b=15.89(1), c=10.00(1) Å, β=100.1(1)°, space group P21, and Z=4. The structure was solved by the Patterson and Fourier technique and was refined by the block-diagonal least-squares method to R=0.061. The unit cell contains two crystallographically independent complex cations, the structure of which are very similar to each other. The complex cation is dimeric; there are two Cu atoms, and each of the two cyclo-L-histidyl-L-histidylato ligands bridges two metal atoms. Except for the aqua ligand, the main body of the complex has an approximate twofold axis which passes through the two metal atoms and relates the ligands to each other. The two Gu atoms have different coordination geometries. One Gu atom has a flattened tetrahedral coordination by 4N atoms, whereas the other is surrounded by 2N and 3O atoms and is intermediate between the square pyramid and the trigonal bipyramid.
  • Makoto Chikira, Hiroshi Yokoi
    1977 Volume 50 Issue 12 Pages 3232-3236
    Published: 1977
    Released: April 19, 2006
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    The angle between the g⁄⁄ axis and the copper-copper axis in most parallel planar dimers of the quadridentate salicylaldehyde Schiff base complexes of copper(II) in toluene or xylene has been reconfirmed to be not ≈35°, but ≈17°, by a computer simulation of the dimer ESR spectra at both the K and X-bands. In order to remedy the shortcomings of the so-called point-dipole approximation generally used in the simulation, a delocalization model, in which the delocalization of each unpaired electron on the copper atom and its surrounding four ligand atoms is explicitly taken into consideration, has been discussed in some detail. The delocalization effect has been proven to be highly significant in estimating dimeric structures reliably. An application of this model to the structural estimation of several dimers in solutions has also been made.
  • Masaaki Kojima, Junnosuke Fujita
    1977 Volume 50 Issue 12 Pages 3237-3244
    Published: 1977
    Released: April 19, 2006
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    Four stereoisomers, mer-Δ, mer-Λ, fac-Δ, and fac-Λ, of the tris[(S)-1,3-butanediamine]cobalt(III) complex were obtained, and their absorption and circular dichroism spectra were recorded in water in the absence or presence of sulfate ions. The shift of absorption bands and the variation of circular dichroism spectra caused by the addition of sulfate ions seem to be correlated with the conformational instability of six-membered (S)-1,3-butanediamine chelate rings in the complexes.
  • Hideo Kise, Hiroyuki End\={o}, Manabu Sen\={o}
    1977 Volume 50 Issue 12 Pages 3245-3250
    Published: 1977
    Released: April 19, 2006
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    The reactions of N-picolinoyl-S,S-tetramethylenesulrilimine and N-trimethylammoniopicolinamidate with dichlorobis(benzonitrile)palladium(II) and dipotassium tetrachloroplatinate(II) afforded chelate complexes of formula MCl2[Ylide]. The structures of the complexes were examined by IR and NMR spectroscopy, and determined as mononuclear complexes with ligands coordinated through two nitrogen atoms. A reverse relationship between pKa values of the ylides and C=O stretching band frequency shifts on complex formation was found, and the nature of the coordination via ylidic nitrogen was discussed in terms of σ- and π-character of the ligands in the chelate complexes and several related bis-ylide complexes.
  • Makoto Watanabe, Masao Ito, Shoji Sato, Tamotsu Yamada
    1977 Volume 50 Issue 12 Pages 3251-3254
    Published: 1977
    Released: April 19, 2006
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    The glassy and crystalline thermal products were prepared by heating a mixture of sodium phosphate glass and germanium dioxide with P/Ge ratios of 1.0–300 at 1000 °C for 3 h in a platinum crucible, and by then rapidly quenching the resulting melt. The thermal products with P/Ge ratios larger than 50 were glassy. The products with P/Ge ratios smaller than 30 were a mixture of glassy and crystalline substances, and the quantity of the glassy substance in the mixture increased with an increase in the P/Ge ratio. The crystalline substance was insoluble in water. From the results of the distribution and the average chain length of the condensed phosphates present in the glassy thermal products, it was concluded that the glass has P–O–Ge linkages and that the most reasonable chemical structure of the glass is (Remark: Graphics omitted.). The colorimetric determination of the phosphorus and germanium contained in the crystalline thermal product showed that the P/Ge ratio of the crystalline substance is 1.3. The value of the P/Ge ratio corresponds to that of Ge3(PO4)4.
  • Isao Sanemasa, Tsutomu Hirata
    1977 Volume 50 Issue 12 Pages 3255-3258
    Published: 1977
    Released: April 19, 2006
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    The disproportionation constants for the Hg22+\ ightleftarrowsHg(aq)+Hg2+ reaction have been measured in dilute mercury (I) perchlorate solutions over the temperature range from 15 to 30 °C. The technique was based on a simple kinetic method which made use of a characteristic property of the elemental mercury in aqueous solutions. The disproportionation constant at 25 °C and μ=0.1 was found to be 1.1±0.1×10−8 M, and the associated thermodynamic parameters were ΔH=13.2±0.2 kcal/mol and ΔS=8.0 e.u. The reliability of the method was discussed with relation to the reported values in the literature.
  • Hideaki Tanaka, Hiro Kuma, Shoichiro Yamada
    1977 Volume 50 Issue 12 Pages 3259-3264
    Published: 1977
    Released: April 19, 2006
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    Cobalt(II), nickel(II), and copper(II) complexes with acetaldehyde oxime and benzaldehyde oxime have been prepared and characterized by vibrational and electronic spectroscopy, magnetism, and other methods. The cobalt(II) and nickel(II) complexes isolated are of the general formulae: (A) MX2(oxime)4 (X=Cl, Br, I, NO3, NCS and CH3COO); (B) M(NCS)2(oxime)2; (C) MSO4 (oxime)3·3H2O. They are all six-coordinate, and the complexes (B) are probably multinuclear. Copper(II) forms complexes of the formulae: (A) CuX2(oxime)4 (X=Cl, Br), (B) CuX2(oxime)2 (X=Cl, Br, NCS); (C) CuSO4(oxime)H4·H2O. Possible structures for these copper(II) complexes are also discussed. Acetaldehyde oxime and benzaldehyde oxime are unidentates in all these complexes, being coordinated through their nitrogen atom.
  • Yoshiro Terai, Hiroaki Kido, Kazuo Saito
    1977 Volume 50 Issue 12 Pages 3265-3267
    Published: 1977
    Released: April 19, 2006
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    The circular dichroism (CD) peaks of trans(N, ethylene)[PtCl(L-am)(C2H4)] (L-am, L-amino carboxylate) in acetonitrile (AN) at 33000 and 37000 cm−1 are characteristic of those complexes with asymmetric nitrogen. The CD sign depends on the substituents on the asymmetric nitrogen, and the additivity law holds for methyl and benzyl derivatives of L-prolinato, L-hydroxyprolinato, and L-valinato complexes. The quadrant rule is applicable to the contribution of the substituents on the nitrogen. On the preparation of the benzyl-L-valinato complex from Zeise’s salt in a weakly acid medium the nitrogen exhibits a marked stereoselectivity to give R configuration.
  • Shinichi Inoue, Nobuyoshi Asai, Gorou Yasuda, Takuya Hori
    1977 Volume 50 Issue 12 Pages 3268-3270
    Published: 1977
    Released: April 19, 2006
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    Six new-sydnones [3-(3-pyridyl)-4-(p-chlorophenyl)sydnone (1), 3-(3-pyridyl)-4-(p-tolyl)sydnone (2), 3-(3-pyridyl)-4-(p-nitrophenyl)sydnone (3), 3-(3-pyridyl)-4-(p-aminophenyl)sydnone (4), 3-(3-pyridyl)-4-(p-acetamidophenyl)sydnone (5), and 3-phenyl-4-(α-phenylstyryl)sydnone (6)] were synthesized and examined for photochromic behavior. Sydnone 2 exhibited photochromism in the solid state upon UV irradiation (230–580 nm).
  • Shizuyoshi Sakai, Hiroji Niimi, Yoshihiro Kobayashi, Yoshio Ishii
    1977 Volume 50 Issue 12 Pages 3271-3275
    Published: 1977
    Released: April 19, 2006
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    Reactions of phenyl isothiocyanate with cyclic and acyclic dibutylstannyl dialkoxides derived from several alcohols, such as 1,2- and 1,3-diols and methanol, afforded quantitatively phenyliminocarbonate derivatives with the elimination of dibutylstannyl sulfide. Cyclic organostannyl sulfides, such as 2,2-dibutyl-1,3,2-oxathiastannolane and -dithiastannolane, reacted with phenyl or alkyl isothiocyanate to give 2-imino-oxathiolane (10) and -dithiolane (14), respectively. At higher reaction temperatures, rearrengment and decomposition of products 10 and 14 occurred.
  • Masanori Utaka, Masahisa Takatsu, Akira Takeda
    1977 Volume 50 Issue 12 Pages 3276-3280
    Published: 1977
    Released: April 19, 2006
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    As models for acetyl-α-chymotrypsin, 4-acetoxymethylbenzimidazole (2), its 5-methyl derivative 3 and 2,5-dimethyl derivative 4 were synthesized from o-toluidine in moderate yields. Their hydrolytic reactivities were determined in water at 50 °C in comparison with their open-chain analog, 4-(acetoxyethyl)imidazole(1). The rate constant (k1) for intramolecular general base catalysis by the imidazolyl group of 2 was 1.6 times larger than k1 for 1. A corrected relative rate of 4.1 is obtained by correcting the basicity difference and the polar substituent effect. The value of 4.1 is an expected magnitude of the effect of freezing an internal rotation as reported for 4,5-(1-acetoxymethyltetramethylene)imidazole. The 5-methyl group of 3 enhances the k1 value 1.4 times as large as that for 2. The enhancement can be attributed to restriction of the second internal rotation. The hydrolytic reactivity of 4 is discussed.
  • K\={o}ji Oe, Masashi Tashiro, Otohiko Tsuge
    1977 Volume 50 Issue 12 Pages 3281-3287
    Published: 1977
    Released: April 19, 2006
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    Irradiation of 2,5-diphenyloxadiazole 1 with benzothiophene 6a gives 3-benzoylbenzothiophene 7, its benzoylhydrazone 8, and/or the oxadiazepine 9; the yields depended on the nature of solvents. With benzophenone as a sensitizer, the photochemical reaction of 1 with 6a forms the [2+2] cycloadduct 12. It is found that 9 is photochemically dissociated to 1 and 6a. In the case of 2-methylbenzothiophene 6b, 3-benzoyl-2-methylbenzothiophene benzoylhydrazone 18 is formed, and with benzophenone as a sensitizer the [2+2] cycloadduct 19 is obtained. In the absence or presence of benzophenone, however, irradiation of 1 with 3-methylbenzothiophene 6c gives the [2+2] cycloadduct 20. The photochemical reaction of 1 with 6a or 6b in the presence of iodine gives the corresponding 3-benzoylbenzothiophene, 7 or 21, and benzoylhydrazone, 8 or 18, respectively. In the case of 6c, however, the [2+2] cycloadduct 23 is formed, together with 2-benzoyl-3-methylbenzothiophene 22. Mechanistic considerations of these reactions are also described.
  • Katuzi Kitatani, Tamejiro Hiyama, Hitosi Nozaki
    1977 Volume 50 Issue 12 Pages 3288-3294
    Published: 1977
    Released: April 19, 2006
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    The title carbenoids (7 and 8) prepared by the action of butyllithium on dihalocyclopropanes are smoothly methylated with methyl iodide. The product ratio of cis-methylated product (3)/trans-methylated one (4) (or endo-methylated product (5)/exo-methylated one (6) is found to depend on the aging period of the carbenoids; thermodynamic equilibration gives almost 3 or 5. This procedure has been extended to general alkylation by utilizing HMPA co-solvent. The resulting α-alkylated cyclopropyl halides are converted into allylic acetates or cyclopropyl acetates upon acetolysis and also into alkylidenecyclopropanes upon base treatment. The protonolysis of 8 gives trans- or exo-bromocyclopropanes stereoselectively.
  • Hiromichi Besso, Kimiaki Imafuku, Hisashi Matsumura
    1977 Volume 50 Issue 12 Pages 3295-3297
    Published: 1977
    Released: April 19, 2006
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    The tautomeric constants Kt of several 4-pyridinethiones were determined by measurement of pKa values. For 2-substituted 5-methoxy-4-pyridinethiones, the Kt values are correlated to the substituent constants σ, by the equation logKt=4.00+3.99σm−7.33σ0.
  • Yoshihiro Ashihara, Yasuyuki Nagata, Kazu Kurosawa
    1977 Volume 50 Issue 12 Pages 3298-3301
    Published: 1977
    Released: April 19, 2006
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    The oxidation often 2-phenyl-2H-1-benzopyrans with potassium permanganate in acetone has been found to give the corresponding flavones in 8–73% yields. The reaction mechanism is discussed on the basis of the substituent effect and the oxidations of related compounds.
  • Hiroshi Yoshida, Tsuyoshi Ogata, Saburo Inokawa
    1977 Volume 50 Issue 12 Pages 3302-3304
    Published: 1977
    Released: April 19, 2006
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    The reaction of S,S-diphenyl- and S,S-dimethyl-N-imidoylsulfimides (1 and 2) with carbon disulfide was studied. 1 yielded nitrile, isothiocyanate, diphenyl sulfide, and sulfur, whereas 2 gave N-thiocarbonyl-S,S-dimethylsulfimide together with isothiocyanate. Kinetic studies indicate that the reaction proceeds via a [2+2]cycloaddition mechnism, as is shown by the small effects of the solvents and the substitutent on the rate.
  • Juji Yoshimura, Ken-ichi Sato, Hironobu Hashimoto, Kuniaki Shimizu
    1977 Volume 50 Issue 12 Pages 3305-3309
    Published: 1977
    Released: April 19, 2006
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    Synthesis of benzyl α- and β-kasugaminides (benzyl 2,4-diamino-2,3,4,6-tetradeoxy-α- and β-D-arabino-hexopyranosides) was carried out by the simultaneous substitution at 2,4-positions of 2,4-di-O-mesyl-abequosides (3,6-dideoxy-2,4-di-O-mesyl-α- and β-D-xylo-hexopyranosides) with sodium azide followed by hydrogenation. The substitution in N,N-dimethylformamide at higher temperature gave the elimination products (4-azido-2,3-unsaturated derivatives) and the subsequently rearranged products (3,4-unsaturated 2-azido derivatives), but, that in hexamethylphosphoric triamide at lower temperature gave the desired compounds in fairly good yields.
  • Takahiro Kaneda, Soichi Misumi
    1977 Volume 50 Issue 12 Pages 3310-3314
    Published: 1977
    Released: April 19, 2006
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    The electronic spectra of TCNE complexes of acyclic and cyclic diacetylenes and cyclic tetraacetylenes were measured. They show a maximum in the narrow region 423–431 nm regardless of ring strain in the donor molecules and proximity of two diacetylene groups. Crystalline two-to-one TCNE complexes of [m.n]paracyclophadiynes were prepared, the formation of one-to-one TCNE complexes in solution being established by means of the Benesi-Hildebrand plots using various molar ratios of the two components. The electronic spectra of some 1: 1 [m.n]paracyclophadiyne–TCNE complexes were measured. The spectra suggest that the complexes are equilibrium mixtures consisting of three isomeric complexes, i.e., a diacetylene-site complex and two pseudo-conformers of benzene-site complex. The longer wavelength band of [m.n]paracyclophadiyne complexes shows a marked red-shift as compared with the other bands. This is interpreted in terms of transannular π-π interaction between the diacetylene group and the benzene ring fixed closely with each other by shortening of methylene bridges. The contribution of the three isomeric complexes on the red-shift is discussed.
  • Hiroshi Yoshida, Tsuyoshi Ogata, Saburo Inokawa
    1977 Volume 50 Issue 12 Pages 3315-3319
    Published: 1977
    Released: April 19, 2006
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    Twenty-five imidoyl triphenylphosphonium methylides III were prepared from triphenylphosphonium methylide and imidoyl chlorides or imidates in moderate yields. The configration of these ylides was assigned on the basis of NMR spectroscopic studies. N-Tosyl substituted ylides showed no reactivity toward aldehydes, whereas N-aryl substituted ylides could be converted easily into α,β-unsaturated ketimines in good yields. The reaction of III with carbon disulfide was also studied.
  • Ichiro Takagi, Yasuhito Tazuke, Keizo Naya
    1977 Volume 50 Issue 12 Pages 3320-3323
    Published: 1977
    Released: April 19, 2006
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    Petasitin, a component isolated from a wild variety of Petasites japonicus Maxim., has been shown to be 3α-[(Z)-2-methyl-2-butenoyloxy]-11-hydroxyeremophila-6,9-dien-8-one, and has been synthesized from the known isopetasin by photosensitized oxygenation.
  • Tadashi Suehiro, Akira Suzuki, Yasuyoshi Tsuchida, Junji Yamazaki
    1977 Volume 50 Issue 12 Pages 3324-3328
    Published: 1977
    Released: April 19, 2006
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    Phenyl radicals derived from benzoyl peroxide (BPO) showed nucleophilic behavior, rho=+0.18 (metaseries) for the hydrogen abstraction reaction from substituted toluenes at 80 °C, and a kinetic deuterium isotope effect, kHkD=3.73±0.2, was found for toluene. Comparison of these results with those for the phenyl radicals from phenylazotriphenylmethane (PAT) leads to the suggestion that the phenyldiazenyl radicals derived from PAT abstract hydrogen from toluene to yield benzene, which should amount to about 50% of the total benzene formed.
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