Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 57 , Issue 12
Showing 1-50 articles out of 50 articles from the selected issue
  • Osamu Ikeda, Ken-ichi Watanabe, Yasuhiko Taniguchi, Hideo Tamura
    1984 Volume 57 Issue 12 Pages 3363-3367
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Adsorption effects of ureas and thioureas on electrode kinetics were studied by using the electrode reactions of Zn2+/Zn(Hg) and Eu3+/Eu2+. The standard rate constant for Zn2+/Zn(Hg) is controlled by the inner-layer permittivity. The effect of this permittivity has been explained in terms of the solvent reorganization energy. The effect of the adsorbates on the electrode kinetics of Eu3+/Eu2+ cannot be explained in terms of the inner-layer permittivity. These two results suggest different locations for the formation of the activated complex: Inside the adsorption layer for Zn2+ and just outside layer for Eu3+.
  • Kimiko Mizutani, Takakazu Yano, Atsushi Sekiguchi, Kazuko Hayashi, Shi ...
    1984 Volume 57 Issue 12 Pages 3368-3377
    Published: 1984
    Released: June 27, 2006
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    To elucidate the electronic mechanism of the quenching of electronically excited Li atoms by H2 molecules, CASSCF calculations were made regarding the Li–H2 system with various geometries. Special attention was payed to the electronic structure of the system in the crossing, or pseudocrossing, region of the potential energy surfaces. Simple CASSCF functions do not have a satisfactory spacial symmetry when the upper and the lower states are almost degenerate in energy, and need to be refined by the addition of a nonorthogonal CI. In the crossing region, electron density maps have shown that the Li atom is bonded more strongly to the nearer H atom than to the farther H atom in the ground state, whereas the opposite is the case for an excited state. Such properties of the wave function lead naturally to a picture of a nonadiabatic process occurring in the crossing region. The pseudocrossing of the first excited and the ground state potential energy surfaces has also been found for all geometries midway between the C2v and C∞v symmetries.
  • Hisao Negita, Toshinori Suzuki, Tsuneo Kubo, Michio Maekawa, Shinei Gi ...
    1984 Volume 57 Issue 12 Pages 3378-3380
    Published: 1984
    Released: June 27, 2006
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    The 14N and 35Cl NQR and 14N spin-lattice relaxation have been studied at various temperatures on the 1 : 2 molecular complex of 1,4-diazabicyclo[2.2.2]octane (DABCO) with CHCl3. Two transitions have been observed near 123 K and 138 K. In the lowest temperature phase a minimum in the T1 was observed and attributed to the axial reorientation of DABCO molecules. The activation energy for this motion was determined to be 12.1±1.2 kJ mol−1. The electron population is discussed for the DABCO complexes with CHCl3 and CDCl3 using the Townes-Dailey treatment.
  • Yasuyuki Takeda, Yoshihiko Ohyagi, Sadatoshi Akabori
    1984 Volume 57 Issue 12 Pages 3381-3385
    Published: 1984
    Released: June 27, 2006
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    The formation constants for 1 : 1 complexes of benzo-18-crown-6 (B18C6) with alkali metal ions and the solubility of B18C6 in various solvents were determined at 25 °C by conductometry and spectrophotometry, respectively. In general, the selectivity of B18C6 for alkali metal ions is governed primarily by the size relationship between cations and the B18C6 cavity. For a given alkali metal ion, the solvation ability of the solvent plays the most important role in determining stability sequences of the B18C6 complex in the solvents. Transfer activity coefficients of B18C6-alkali metal ion complexes were calculated. The transfer activity coefficient of the B18C6 complex from methanol to aprotic solvents somewhat varies with alkali metal ions in the B18C6 cavity. The magnitudes of the transfer activity coefficients of the B18C6 complex from acetonitrile and propylene carbonate to DMF and DMSO are determined mainly by the relative strength of the solvation ability of the former group and the latter group for the alkali metal ion in the B18C6 cavity. In methanol, due to the hydrogen bonds between ether oxygen atoms of B18C6 and methanol, the B18C6 complex is more strongly solvated than the corresponding alkali metal ion, compared to the case of the aprotic solvents.
  • Tetsuya Osaka, Takashi Kitai
    1984 Volume 57 Issue 12 Pages 3386-3390
    Published: 1984
    Released: June 27, 2006
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    The charge-discharge characteristics of the anion-doped lithium–polyacetylene [(CH)x] battery was investigated by means of the FFT impedance method, by which the impedance-frequency dispersion could be measured by very high speed. The charging and self-discharging of the Li–(CH)x battery were represented by the Randles-type equivalent circuit, added with the corrective term concerned with surface roughness. These processes and their doping states of the (CH)x film were readily detected by the variation in the resistive component, Rr, in the equivalent circuit. The Rr value of the self-discharge process was clearly correlated to the open-circuit voltage, Voc, regardless of the charging current; furthermore, it was strongly indicated that the self-discharge process is mainly caused by the dopant diffusion from the interface into the interior part of (CH)x films. For the discharging process, another mechanism, closely concerned with dopant diffusion, was suggested by the impedance results.
  • Takeshi Ohno, Shunji Kato
    1984 Volume 57 Issue 12 Pages 3391-3394
    Published: 1984
    Released: June 27, 2006
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    The excited states of rhodium(III) compounds including [Rh(4,7-diphenyl-1,10-phenanthroline)3]3+ ([Rh(dp-phen)3]3+), [Rh(1,10-phenanthroline)3]3+ ([Rh(phen)3]3+), [RhCl2(dp-phen)2]+, and [RhCl2(phen)2]+, have been investigated by means of emission spectroscopy and laser photolysis spectroscopy. The transient species with the lifetime of 0.055–72 μs are identified as the triplet (π-π*) excited state of the ligand for [Rh(dp-phen)3]3+ and [Rh(phen)3]3+ and as the triplet ligand-field excited states for [RhCl2(dp-phen)2]+ and [RhCl2(phen)2]+. The molar absorption coefficients of the excited states are 9600 M−1 cm−1 at 550 nm for [Rh(dp-phen)3]3+, 2750 M−1 cm−1 at 560 nm for [RhCl2(dp-phen)2]+, 2300 M−1 cm−1 at 510 nm for [Rh(phen)3]3+, and 1600 M−1 cm−1 at 550 nm for [RhCl2(phen)2]+. The lifetime of the ligand-field excited state of [RhCl2(phen)2]+ (700 ns in acetonitrile) decreases to 55 ns in water.
  • Kazuaki Nakata, Hiroshi Sugihara, Shinya Mori, Hiroshi Yamaguchi, Yosh ...
    1984 Volume 57 Issue 12 Pages 3395-3398
    Published: 1984
    Released: June 27, 2006
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    An improved method for the determination of the orientation distribution function of a powder consisting of preferentially oriented plate-like and needle-like particles was reported. Using this method, the coarse and fine powders of benzamide and α-2-pyrazinecarboxamide were investigated. It was found that the domains (a domain is defined as a collection of particles having the same preferred orientation plane or axis) of preferentially oriented particles exhibit two distinct changes when undergoing grinding of the powder. One change involves a decrease and the other an increase in volume, indicating that the particles in the domain showing the former change transform into those in the domain showing the latter change following grinding. The increase in volume of the domain can be well explained in relation to the existence of molecular layers connected to each other by weak van der Waals force in the crystal.
  • Hiroyuki Kawano, Tsutomu Kenp\={o}
    1984 Volume 57 Issue 12 Pages 3399-3402
    Published: 1984
    Released: June 27, 2006
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    Combined techniques of molecular beam effusion from a Knudsen cell and of positive surface ionization on a heated polycrystalline rhenium filament were employed to determine the vapor pressures P (in atm) of LiI and KCl as a function of cell temperature T (in K), thereby yielding the equations:
    log10P(LiI)=(7.498±0.046)−(9254±30)⁄T for 583–717 K,
    log10P(KCl)=(7.210±0.058)−(11135±45)⁄T for 687–877 K.
    The present data on the pressure and on both entropy and enthalpy of sublimation are compared with others in literature.
  • Masako Tanaka, Hiroshi Sakuma, Osamu Kohanawa, Seijun Fukaya, Meiseki ...
    1984 Volume 57 Issue 12 Pages 3403-3407
    Published: 1984
    Released: June 27, 2006
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    The reaction of (R)-4-amino-3-isoxazolidinone (cycloserine) with OH radicals was studied in aqueous solutions by optical pulse radiolysis at pHs 6.5–12. It was concluded, from a comparison of the transient spectra with those obtained in a reaction with N3 radicals, that OH radicals attacked at the dissociated peptide group, –NCO–, and an oxidized radical, –\dotNCO–, was produced through one-electron oxidation. From a kinetic analysis, the reaction was considered to have proceeded by two steps: The first step was the formation of OH adducts, where the rate constant, k(OH+cycloserine), was 8×109 mol−1 dm3 s−1 for the zwitterion form of cycloserine at pH 6.5 and 1.2×1010 mol−1 dm3 s−1 for anion form at pHs 8–10. The second step was the formation of oxidized radicals at a rate of 3–4×106 s−1. These radicals decayed with a second-order rate, suggesting a radical-radical recombination. D-Serine was detected as the major product.
  • Shunzo Yamamoto, Shuzo Matsuda, Chihiro Ozaki, Hiroshi Takahoso, Norio ...
    1984 Volume 57 Issue 12 Pages 3408-3412
    Published: 1984
    Released: June 27, 2006
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    The mercury- and cadmium-photosensitized reactions of γ-butyrolactone have been compared. The products obtained in the two photosensitizations were quite different. The gaseous products from the mercury-photosensitized reaction were carbon dioxide, cyclopropane, and propylene, while the products obtained in the cadmium-photosensitized reaction were carbon monoxide and ethylene. This difference suggests that the decomposition of γ-butyrolactone takes place through different intermediates in the two reactions. Possible mechanisms are discussed.
  • Kunio Furusawa, Hiroyuki Kakoki, Hideo Matsumura
    1984 Volume 57 Issue 12 Pages 3413-3418
    Published: 1984
    Released: June 27, 2006
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    Aggregation behavior of phosphatidylethanolamine (PE) and Phosphatidylserine (PS) vesicles that have resulted with various metal cations, has been studied to determine their adsorption characteristics. The critical flocculation concentration of these cations for both vesicles was determined by two techniques, i.e., by the kinetic method in which the rate of flocculation was measured turbidimetrically, and by the traditional static method. The results have been analysed by the usual stability concept in the colloid chemistry, and these analyses revealed that there are two mechanisms in the vesicle aggregation. One is the charge neutralization of the polar groups on the vesicle surface, which is induced by the adsorption of multivalent cations (Th4+, La3+), and the other is the interparticle binding (or the interparticle bridging) caused by the divalent cations (Ca2+, Mg2+).
  • Kazuhiko Kandori, Kijiro Kon-no, Ayao Kitahara
    1984 Volume 57 Issue 12 Pages 3419-3425
    Published: 1984
    Released: June 27, 2006
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    The dispersion stability of titanium dioxide particles and two kinds of iron(III) oxide particles in dioxane–water mixtures was studied as a function of the dielectric constant(ε=2.2–78). The sedimentation of dispersions, the adsorption of sodium 1,2-bis(2-ethylhexyloxycarbonyl)ethanesulfonate (Aerosol OT or AOT) on the particles, and the zeta potential were measured. In the absence of AOT, the dispersions of all the particles were rapidly flocculated over all of the region of the dielectric constant, and little effect of the dielectric constant on the dispersibility was observed. In the presence of AOT, however, the dispersions of all the kinds of particles used were stabilized at both the lower(ε=2.2) and higher(ε=60–78) regions of the dielectric constant by the adsorption of AOT on the particles. However, the flocculation was accelerated for all kinds of particles, and AOT molecules were not at all, or scarcely, adsorbed on the particles in the middle region of the dielectric constant(ε=10–50). This behavior of the dispersibility corresponded with the results of the dynamic light scattering of the AOT solution, which reveal the aggregation of AOT molecules at various dielectric constants. The zeta potential changed from a positive sign to a negative sign with the increase in the dielectric constant, and the isoelectric dielectric point (IED), which means a zero value of the zeta potential, appeared. The order of the values of IED among the three kinds of particles agrees with the order of the isoelectric points(IEP) of the particles. This result can, therefore, be explained by the concept of the acid-base interaction between a particle and a solvent in dioxane–water mixtures.
  • Hisako Itoh, Yukihiro Ikegami, Yasuo Suzuki
    1984 Volume 57 Issue 12 Pages 3426-3429
    Published: 1984
    Released: June 27, 2006
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    The stability constants of scandium complexes with malonate, maleate, itaconate, glutarate, adipate, and succinate ligands were determined titrimetrically at 25.0 °C and at an ionic strength of 0.1. The chelate effect was negligible for the stability of the scandium complexes with the dicarboxylate ligands studied in contrast with the lanthanoid complexes. The complex formation of scandium might be explained by an electrostatic ionic bond similar to ones exhibited in the lighter rare-earth complexes, due to linear relationships between the stability constants and the ionic potential Z2r.
  • Reiko Saito, Yoshinori Kidani
    1984 Volume 57 Issue 12 Pages 3430-3436
    Published: 1984
    Released: June 27, 2006
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    (1RS,2SR,3SR)-3-Methyl-1,2-cyclohexanediamine (3m-chxn), a methyl derivative of cis-1,2-cyclohexanediamine, was prepared and optically resolved. The absolute configurations of the enantiomers obtained were assigned on the basis of the Cotton effect of the trans-dichlorobis(diamine) complexes, each containing active 3m-chxn. The complexes of the [Pt(NH3)2L]2+, [Pt(en)L]2+, and [CoL3]3+ types (en=1,2-ethanediamine, L=R,S,S- or S,R,R-3m-chxn) were also synthesized and characterized on the basis of their absorption, CD, and 13C NMR spectra. It has been found that the chelate rings adopted by R,S,S- and S,R,R-3m-chxn predominantly take the δ and λ conformations respectively, because of the preferred equatorial orientation of the C2–C3 bond of the cyclohexane ring. The four diastereomers of [Co(R,S,S-3m-chxn)3]3+ were chromatographically isolated and assigned to fac-Λ(lel3), mer-Λ(lel3), fac-Δ(ob3), and mer-Δ(ob3).
  • Yasushi Inoue, Hiromichi Yamazaki
    1984 Volume 57 Issue 12 Pages 3437-3442
    Published: 1984
    Released: June 27, 2006
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    The distribution coefficients of hydrous tin(IV) oxide for various cations were measured. The affinity series for alkali-metal ions and alkaline-earth-metal ions were Li+>>Na+>K+>Rb+≥Cs+ and Mg2+>Ca2+>Sr2+≈Ba2+ respectively; the values decreased in the order of the increasing crystal radii of the cations. For transition-metal ions, which showed a markedly high affinity, the distribution coefficients had a strong correlation with the hydrolysis constants of the cations and the stability constants of their acetato complexes. Based on these findings, the transition-metal ions are considered to be adsorbed on the exchanger by a bond partially covalent in character, rather than by a pure ionic bond. By using NH4Cl and HClO4 solutions as eluants, nearly quantitative separations of Cs–Na–Li and Cs–Na–Sr were effected with a relatively small column. The applicability of the exchanger to the group separation of actinoids from long-lived fission products was also suggested.
  • Hideaki Kanno, Shunji Utsuno, Junnosuke Fujita
    1984 Volume 57 Issue 12 Pages 3443-3449
    Published: 1984
    Released: June 27, 2006
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    New acetylacetonato (acac) chromium(III) complexes of the type, [Cr(acac)3−nLn]n+ (n=1 and 2), where L denotes a seven-membered chelate ligand, 2,2′-bipyridine N,N′-dioxide (bpdo) or 3,3′-dimethyl-2,2′-bipyridine N,N′-dioxide (rac- or R-mbdo), were prepared. Optically active [Cr(acac)2(R-mbdo)]+ and [Cr(acac)(R-mbdo)2]2+ yielded only one isomer and were assigned to Δ(λ)(lel) and Δ(λλ)(lel2), respectively, on the basis of the circular dichroism spectra and molecular models. The [Cr(acac)(mbdo)2]2+ complex prepared from rac-mbdo formed two racemates of diastereomers, lel2(Δ(λλ), Λ(δδ)) and lel·ob (Δ(λδ)), Λ(δλ), whereas [Cr(acac)2(bpdo)]+ formed only lel(Δ(λ), Λ(δ)) isomer which was resolved by column chromatography. Both rac- and (−)589[Cr(acac)(bpdo)2](ClO4)2·H2O resolved by a chemical method were found to crystallize in lel2 isomer, but isomerize to the isomer in aqueous solution with the rate of 3.31×10−3 s−1 at 295.2 K, the rate constant for racemization (Δ\ ightleftarrowsΛ) being 1.08×10−4 s−1 at 295.2 K. An intramolecular conformational inversion of the bpdo chelate ring for the isomerization and an intramolecular twist mechanism for the racemization were proposed.
  • Yukio Yamamoto, Seiji Oka, Koichiro Hayashi
    1984 Volume 57 Issue 12 Pages 3450-3453
    Published: 1984
    Released: June 27, 2006
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    The oxygen-plasma treatment of column packings for gas chromatography was examined with diatomaceous earth coated with several kinds of stationary liquid phases from the point of view of the modification of their chromatographic properties. A remarkable effect on the gas chromatograms of polar compounds was observed for the packings with nonpolar liquids, such as squalane and Apiezon L. The elimination of tailing and the improvement of the resolution by the plasma treatment were attributed to the incorporation of oxygen into the hydrocarbon liquids and the formation of crosslinked products covering the adsorptive support surface. These results were compared with the previous data on argon-plasma treatment.
  • Masayuki Kuzuya, Akihiro Noguchi, Takachiyo Okuda
    1984 Volume 57 Issue 12 Pages 3454-3460
    Published: 1984
    Released: June 27, 2006
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    The tautomeric properties of 2-pyridones–2-pyridinols exerted by the substituent effect were discussed on the basis of quantum chemical quantities deduced from molecular orbital (MO) calculations. A substituent at the 6-position has the greatest stabilizing effect. The magnitude of this effect was greater on the 2-pyridinol form than the 2-pyridone form, irrespective of the nature of the substituent. This led to a large predominance of the 2-pyridinol form on the 6-polar-substituted derivatives to such an extent that it was observed by conventional UV measurements at ambient temperature. In the 6-methyl derivative, the 2-pyridinol form was not observed by a similar measurement due to the weak substituent effect. The association ability is still an important factor in determining tautomeric equilibrium in a solution, resulting in a strong lability to the molecular environment. The substituent effects on the stabilities of both tautomers were shown to be correlated with the N-atomic charges and ring structural modifications of the tautomers.
  • Masayuki Kuzuya, Akihiro Noguchi, Takachiyo Okuda
    1984 Volume 57 Issue 12 Pages 3461-3465
    Published: 1984
    Released: June 27, 2006
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    We have studied the catalytic activities of various substituted 2-pyridones on the mutarotation of 2,3,4,6-tetra-O-methyl-D-glucose (TMG). The results in an acetone solution at 37 °C showed that an introduction of the polar substituents into the 5- or 6-position, regardless of the nature of the substituents, retarded the relative rate of the mutarotation as compared to a parent compound, while that of alkyl substituents accelerated such rates. Further striking rate enhancements were observed in 5,6-dimethyl-substituted derivatives. Based on experimental results, we concluded that the 2-pyridones which can act as an effective catalyst are such that the 2-pyridone tautomeric form predominantly exists in solution due to its greater association ability and that the 2-pyridinol tautomeric form is energetically more stable for a lower activation energy of the double-proton transfer process in the 2-pyridone-TMG complex.
  • Yukio Masaki, Kinji Hashimoto, Kazuhiko Sakuma, Kenji Kaji
    1984 Volume 57 Issue 12 Pages 3466-3475
    Published: 1984
    Released: June 27, 2006
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    The ochtodane skeleton, the Carbon framework of 1,1-dimethyl-3-ethylcyclohexane (1) was constructed highly stereoselectively by the acid-catalyzed (SnCl4 or CF3CO2H) cyclization of the terminally functionalized myrcene derivatives, the benzenesulfenyl chloride adduct (7), the terminal β-hydroxy sulfide (8) derived from 7, and myrcene 6,7-epoxide (10). The stereoselectivity of the 3-exo-double bond in 1 formed concomitantly in the cyclization reaction was found to depend remarkably upon the reaction temperature and the 85–94% of E-stereoselectivity was attained at −78 °C. By the method, the ochtodane derivatives with the sulfur- or oxygen-functional groups on the C(6)-position were obtained. Synthetic applications of the ochtodane type compounds (12) and (19) to the aldehyde component (4) of the pheromone of the male boll weevils and to an ochtodane type terpene (26) isolated from the red alga Octodes crockeri, are reported.
  • Yukio Masaki, Kinji Hashimoto, Yuzuru Serizawa, Kenji Kaji
    1984 Volume 57 Issue 12 Pages 3476-3482
    Published: 1984
    Released: June 27, 2006
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    A furyl sesquiterpene pleraplysillin-1 (1), which possesses the ochtodane skeleton (2) in the molecule, was synthesized regio- and stereoselectively starting from the ochtodane type monoterpene (5). Two approaches were investigated: One is the route by way of the benzenesulfenyl chloride addition to a sesquiterpene (9) or (13) which involve the whole carbon framework of 1 and the exocyclic E- or Z-double bond, and the other involves the regioselective formation of the endocyclic double bond of the ochtodane synthon (15) utilizing the hydroxylassisted epoxide opening reaction followed by homologation with the 3-furylmethyl moiety. In both of the routes the geometry of the exocyclic double bond of the ochtodane synthon played an important role in the regioselective formation of the endocyclic double bond in 1.
  • Katsuhiro Saito, Shigenori Iida, Toshio Mukai
    1984 Volume 57 Issue 12 Pages 3483-3487
    Published: 1984
    Released: June 27, 2006
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    Cycloadditions of 1-ethoxycarbonyl-1H-azepine with 5-methoxycarbonyl-2-pyrone gave [4+2] and [4+6] type adducts and a benzazepine derivative, while the reaction of the azepine derivative with 3-methoxycarbonyl-2-pyrone afforded only a [4+2] type adduct. Similarly, an addition of 1-ethoxycarbonyl-1H-1,2-diazepine with 5-methoxycarbonyl-2-pyrone gave a benzodiazepine derivative. Reactions of the azepine and the diazepine derivatives with tetrachlorocyclopentadienone dimethyl acetal afforded [4+2] type adducts.
  • Toshio Itahara, Kazukuni Kawasaki, Fumio Ouseto
    1984 Volume 57 Issue 12 Pages 3488-3493
    Published: 1984
    Released: June 27, 2006
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    Treatments of 1-(2,6-dichlorobenzoyl)-, 3-acetyl-1-(2,6-dichlorobenzoyl)-, 1-(2,6-dichlorobenzoyl)-2-formyl-, and 1-(phenylsulfonyl)pyrroles with palladium acetate and alkyl acrylates gave the corresponding α-alkenyl-substituted pyrroles in good yields, while the reaction of 1-(2,6-dichlorobenzoyl)-2,5-dimethylpyrrole gave small amounts of β-alkenyl-substituted pyrroles. Under similar conditions, 1-(2,6-dichlorobenzoyl)pyrazole and 1-(2,6-dichlorobenzoyl)-3,5-dimethylpyrazole reacted with palladium acetate and alkyl acrylates to give the corresponding 4-alkenyl-substituted pyrazoles. The reaction of 1-(2,6-dichlorobenzoyl)-4-methylpyrazole gave 5-alkenyl-substituted pyrazole
  • Yasuhiro Fujioka
    1984 Volume 57 Issue 12 Pages 3494-3506
    Published: 1984
    Released: June 27, 2006
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    Fourteen macrocyclic polyphenylenes, including the following ten new compounds, were synthesized by intra- or intermolecular homo-coupling of di-Grignard compound and by cross-coupling of two kinds of di-Grignard compounds with copper(II) chloride: m,m,o,p,o-pentaphenylene; o,o,p,o,o,p-, m,o,p,m,o,p-, o,p,o,p,o,p-, m,o,p,o,p,o-, m,o,m,o,m,o-, and m,m,m,o,m,o-hexaphenylene; m,o,p,p,o,m,p-, and m,m,m,m,p,o,p-heptaphenylene; and m,o,o,m,o,o,m,o,o,m,o,o-dodecaphenylene. 1H NMR spectra of the polyphenylenes, compared with those of open-chain analogues, provide valuable information on the nonplanar spacial relationship of constituting phenylene rings. UV spectra of the compounds containing p-phenylene ring(s) suggest that the lack or decrease in intensity of K-band above ca. 260 nm or a marked shift of that band provides useful conformational information. Empirical Hückel molecular orbital calculations of longest-wavelength absorption bands of twelve polyphenylenes were also carried out. The calculations furnish additional bases for their conformational aspects deduced from their spectral data and Dreiding stereomodels. IR spectra indicate that lack of intense band(s) near 700 cm−1 may generally be regarded as a piece of plausible evidence for the macrocyclic structure containing no m-phenylene ring. Stabilities of the polyphenylenes to electron bombardment are also discussed.
  • Kazuo Mukai, Kimiko Takamatsu, Kazuhiko Ishizu
    1984 Volume 57 Issue 12 Pages 3507-3510
    Published: 1984
    Released: June 27, 2006
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    New tocopherol (vitamin E) model compounds (tocopherol 1; 7-t-butyl-2,2-dimethyl-6-chromanol, tocopherol 2; 7-t-butyl-2,2,5-trimethyl-6-chromanol, and tocopherol 3; 5,7-diisopropyl-2,2-dimethyl-6-chromanol) have been synthesized by condensation of 2-methyl-3-buten-2-ol to the corresponding alkylhydroquinone. Electron spin resonance measurements were performed for the tocopheroxyl radicals obtained from the above tocopherol model compounds by oxidizing the phenol precursors with PbO2 in toluene. The proton hyperfine coupling constants and giso-values were determined. The tocopheroxyl radicals 2 and 3 having large alkyl substituents at both ortho positions (C-5 and C-7) are fairly stable, and the radical stability, as measured by the intensities of the ESR signals, increases in the order tocopheroxyl 1<α-tocopheroxyl model<tocopheroxyl 2<tocopheroxyl 3. The result suggests that the in vitro antioxidant activities of tocopherols 2 and 3 are higher than that of α-tocopherol model.
  • Jun-ichi Ueda, Akira Hanaki
    1984 Volume 57 Issue 12 Pages 3511-3516
    Published: 1984
    Released: June 27, 2006
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    The autoxidation catalyzed by copper(II)-poly(L-histidine) was studied by a rapid-mixing spectrophotometric method. The reaction obeys Michaelis-Menten kinetics. The double reciprocal plots of the velocity against the concentrations, i.e. the Lineweaver-Burk plots, of ascorbate and of oxygen gave a straight line. A kinetic analysis of the Lineweaver-Burk plot of the reaction reveals that the autoxidation of ascorbate by Cu(II)–PLH proceeds a so-called Ping-Pong mechanism. Copper(II) ion associates with PLH. The rate of ascorbate autoxidation appeared to depend on the concentration of copper(II) ion in the PLH phase, which is designated as the average binding number. The copper(II) ion concentrated in the PLH phase is highly reactive and is likely to be perturbed by the addition of inert electrolytes. The labile copper(II) ion, which is concentrated in the polymer phase, may be the catalytically active species.
  • Kentaro Takagi, Harutaka Mimura, Saburo Inokawa
    1984 Volume 57 Issue 12 Pages 3517-3522
    Published: 1984
    Released: June 27, 2006
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    The catalytic activity of nickel(0) generated in situ from nickel(II) salt was examined in a dehalogenative coupling of alkenyl halides with zinc powder. The reaction of alkenyl bromides took place provided that potassium iodide was present to assist the reduction of nickel(II) with zinc powder, and also to convert the alkenyl bromides to the corresponding alkenyl iodides. A speculative view concerning the disproportionation step is advanced in an attempt to explain the unique stereochemistry observed.
  • Shuki Araki, Takashi Sato, Hiroyuki Miyagawa, Yasuo Butsugan
    1984 Volume 57 Issue 12 Pages 3523-3525
    Published: 1984
    Released: June 27, 2006
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    Convenient syntheses of vitamin K and coenzyme Q are described. Grignard coupling of polyprenyl diethyl phosphates with 1,4-dimethoxy-3-methyl-2-naphthylmagnesium bromide gave high yields of the polyprenylated hydroquinone dimethyl ethers regioselectively with the preservation of the stereochemistry. The precursors of coenzyme Q were similarly obtained by the coupling of 2,3,4,5-tetramethoxy-6-methylphenylmagnesium bromide and the polyprenyl phosphates. The synthesized (polyprenyl)hydroquinone dimethyl ethers are known to be oxidized to the biologically active quinones.
  • Akira Izuoka, Shigeru Murata, Hiizu Iwamura
    1984 Volume 57 Issue 12 Pages 3526-3530
    Published: 1984
    Released: June 27, 2006
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    7-Diazo-7H-benz[de]anthracene has been prepared by the HgO oxidation of the corresponding hydrazone in ether. The yellow-green diazo compound in a 2-methyltetrahydrofuran matrix has been photolyzed with a high-pressure mercury lamp in an ESR cavity at 14 K. From the X, Y, and Z transitions due to the unoriented triplet species, the zero-field splitting parameters of 7H-benz[de]anthracen-7-ylidene have been determined: |D|=0.2662 and |E|=0.0175 cm−1. A temperature dependence experiment showed linear signal intensities vs. 1⁄T plots, indicating that the carbene is in the ground triplet state. The zero-field splitting parameters have been theoretically calculated by assuming the dipolar interaction of the electron spins one on the n-orbital at the 7-position and the other delocalized on the Hückel π-framework.
  • Saizo Shibata, Hajime Matsushita, Hajime Kaneko, Masao Noguchi, Takao ...
    1984 Volume 57 Issue 12 Pages 3531-3535
    Published: 1984
    Released: June 27, 2006
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    The stereoselectivity of asymmetric transformation of 2-substituted alkanoic acids via oxazolines was clarified by measuring the isomeric ratio of 13C-labeled lithio oxazolines by 13C NMR. The mechanism of the process was discussed from substituent effects of the oxazoline ring and solvent effects on the transformation.
  • Shuichi Sakamoto, Tsutomu Tsuchiya, Toshiaki Miyake, Akihiro Tanaka, S ...
    1984 Volume 57 Issue 12 Pages 3536-3542
    Published: 1984
    Released: June 27, 2006
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    23-Dialkylamino-23-deoxydemycinosyltylosins have been prepared by treating 23-deoxy-23-iododemycinosyltylosin (2) with a series of amines including dimethylamine, diethylamine, and piperidine. 14(23)-Unsaturated derivatives, 23-deoxy-14(23)-enomycaminosyl tylonolide (17) and 23-deoxy-14(23)-enodemycinosyltylosin (4) have also been prepared. The conformation of mycaminosyl tylonolide dissolved in chloroform-d was determined by nuclear Overhauser difference spectroscopy, revealing that the two three-member groups of H(10), Me(22), and H(14) and of H(11), H(13), and H(15) stood, respectively, in a line in this order.
  • Haruo Shiromaru, Shunji Katsumata
    1984 Volume 57 Issue 12 Pages 3543-3551
    Published: 1984
    Released: June 27, 2006
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    Measurements of photoelectron angular distribution were carried out with NeI and HeI resonance lines for Jahn-Teller split bands of methane, ethane, cyclopropane, neopentane, tetramethylsilane, carbon tetrachloride, and ammonia. The variation of an asymmetry parameter β across the band is presented. Significant β variations across the Jahn-Teller split bands due to the l2T2 states of C(CH3)4+ and CCl4+ could not be explained in terms of photoelectron energy dependence of β. These abnormal variations will be discussed on the basis of characteristics of the degenerate molecular orbitals split by the Jahn-Teller effect.
  • Fumio Hama, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1984 Volume 57 Issue 12 Pages 3552-3556
    Published: 1984
    Released: June 27, 2006
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    The molecular structures of [2]paracyclo[2](2,5)furanophane (1) at 20 °C and −150 °C have been determined by means of X-ray diffraction. The crystal is tetragonal, with a=15.996(1), c=8.374(1)Å (at 20 °C), and a=15.823(3), c=8.330(3)Å (at −150 °C), space group P\bar421c and Z=8. The structures were solved by the direct method, and refined anisotropically by the block-diagonal least-squares procedure: R=0.069 and 0.075 for the structures at 20 °C and −150 °C, respectively. The furan ring has an envelope form, and the benzene ring boat-shape.
  • Harumichi Kobashi, Masa-aki Funabashi, Tomoyuki Kondo, Toshifumi Morit ...
    1984 Volume 57 Issue 12 Pages 3557-3565
    Published: 1984
    Released: June 27, 2006
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    Mechanisms of hydrogen atom abstraction reactions by triplet state p-chloranil (3CA) from durene (DH) were studied by picosecond and nanosecond laser photolysis and transient photoconductivity measurements. 3CA was quenched by DH through diffusional encounter to form a triplet ion pair (IP) between CA and DH, p-chloranil semiquinone radical (CAH·), and 2,4,5-trimethylbenzyl radical (D·). Ionic dissociation of IP was observed in 1,2-dichloroethane (DCE) as well as in acetonitrile. However, no transient species was observed by direct excitation of a charge-transfer (CT) band of the electron donor-acceptor (EDA) complex between CA and DH. The H-atom transfer leading to production of CAH· was found to proceed through two distinct mechanisms; H-atom transfer via IP (Mechanism I) and a more rapid transfer competing with IP formation (Mechanism II). The quantum yields of CAH· produced by Mechanisms I and II and the first-order rate constants for proton transfer, ionic dissociation, and intersystem crossing competing with one another in the IP state were estimated to be (0.1 and 0.2) and (2, 5, and 13)×106 s−1, respectively, in DCE at room temperature.
  • Tetsuaki Nishida, Motomi Katada, Yoshimasa Takashima
    1984 Volume 57 Issue 12 Pages 3566-3570
    Published: 1984
    Released: June 27, 2006
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    Mössbauer study of potassium germanate glasses containing a small amount of Sn4+ has been performed to know the relationship between the abnormal composition dependence of physical properties, so-called germanate anomaly, and the local structural change of the glasses. Distinct increases in isomer shift and linewidth and a distinct decrease in quadrupole splitting are observed when the concentration of alkali oxide exceeds about 16 mol%. These changes are ascribed to the formation of nonbridging oxygen atoms in GeO4 units. This is also supported by a drastic decrease in a parameter of intermolecular force constant obtained from the temperature dependence of Mössbauer absorption area. The composition dependence of the parameter is well consistent with that of glass transition temperature (Tg) of the same samples. Transformation of GeO4 tetrahedra into GeO6 octahedra is also confirmed by increases in the parameter of intermolecular force constant and in Tg in the alkali content region lower than 16 mol%. The role of Sn4+ is concluded to be a network modifier which is present at an interstitial site of three-dimensional network composed of GeO4 and GeO6 units.
  • Masaaki Ohta, Kunio Ohzeki
    1984 Volume 57 Issue 12 Pages 3571-3573
    Published: 1984
    Released: June 27, 2006
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    A simple and selective method for the determination of trace amounts of copper is developed. The method is based on the concentration of copper as the complex with bathocuproinedisulfonate (BCS) with the use of finely divided anion-exchange resin, collection of the resin on a membrane filter as the disk of thin layer, and determination of the colored complex in the resin phase by densitometry. The copper(I)–BCS complex in sample volumes ranging from 50–200 cm3 was effectively concentrated by factors ranging from 2500–10000. The method was applied to tap water. Copper at ppb (μg dm−3) level was successfully determined.
  • Yue Ouyang, Masaaki Kojima, Junnosuke Fujita
    1984 Volume 57 Issue 12 Pages 3574-3579
    Published: 1984
    Released: June 27, 2006
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    A series of complexes of the type, [Co(acac)2L]+, where acac=2,4-pentanedionate ion and L denotes R1R2NCH2CH2NR3R4 (R1–R4=H or CH3), N-phenylethylenediamine, N,N′-diphenylethylenediamine, and o-phenylenediamine were prepared and the isomers separated. The absorption spectra and the distributions of the isomers at equilibrium were determined and the results are discussed.
  • Katsuaki Katoh, Hirofumi Sugiura, Kazuo Kashiwabara, Junnosuke Fujita
    1984 Volume 57 Issue 12 Pages 3580-3586
    Published: 1984
    Released: June 27, 2006
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    A large number of new unidentate tertiary phosphine–cobalt(III) complexes containing acetylacetonate ions were prepared. The complexes are grouped into four types; (A) cis- and trans-([Co(acac)2(PRnPh3−n)2]+, (B) trans-[Co(acac)2(H2O)(PRnPh3−n)]+, (C) trans-[Co(acac)2(L)(PMe2Ph)n+, and (D) trans-(P,P)-[Co(acac)(CN)2(PRnPh3−n)2] (acac: acetylacetonate ion, R: CH3(Me), C2H5(Et), n-C3H7(Pr), i-C3H7(Pri), n-C4H9(Bu), i-C4H9(Bui), c-C6H11 (Cy), Ph: C6H5, L: NH3, CH3NH2, C5H5N(py), NCS). The complexes of type A form cis and trans isomers in a different ratio depending upon the bulkiness and basicity of a phosphine ligand, and the ratios for the complexes with R=Me and Et were examined in some detail. The trans isomers of type A show a strong absorption band in the d-d transition region, which is assumed to involve charge transfer transitions between the cobalt(III) ion and a phosphine ligand, while the cis isomers exhibit the first d-d band split into two components with medium intensity. The complexes of type B show a distinct peak of the first d-d band, the energy shifts of which were discussed in terms of the bulkiness and basicity of phosphine ligands. The complexes of types C and D were prepared to compare the chemical and absorption spectral properties with those of complexes of types A and B.
  • Kunihiko Tajima, Yuji Ishikawa, Kazuo Mukai, Kazuhiko Ishizu, Hiromu S ...
    1984 Volume 57 Issue 12 Pages 3587-3588
    Published: 1984
    Released: June 27, 2006
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    A new surface-active porphyrin, 1-dodecyl-4-(10,15,20-triphenyl-5-porphinyl)pyridinium bromide, and its copper complex (Cu(II)DPyTPP) were synthesized. In toluene, chloroform and ethanol, a typical ESR hyperfine structure (hfs) ascribable to monomeric Cu(II) porphyrin was observed. In ethanol containing a buffer of pH=7.4, a reversible formation of the micellar colloid which is strongly dependent on the water/ethanol mixing ratio, was confirmed based on mearsurements of ESR line broadening and the splitting of the Soret band.
  • Akira Tsuboyama, Kouichi Takeshita, Shigehiro Konaka, Masao Kimura
    1984 Volume 57 Issue 12 Pages 3589-3590
    Published: 1984
    Released: June 27, 2006
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    The molecular structures and torsional potentials of (CH3)2O and (CH3)2S have been calculated by the ab initio gradient method using a MIDI-4 basis set augumented with polarization functions. The calculations have confirmed that the molecules take the staggered-staggered conformation with C2v symmetry.
  • Osamu Sekiguchi, Nobuhiro Ohta, Hiroaki Baba
    1984 Volume 57 Issue 12 Pages 3591-3592
    Published: 1984
    Released: June 27, 2006
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    The radiative decay rate constants (kF) for vibronic levels in S1 of pyrazine and pyrimidine were derived by using the quantum yields measured under the conditions of SVL excitation. The vibronic level dependence of kF in pyrazine can be explained by the Herzberg-Teller theory.
  • Kenji Shimizu, Akiko Furuhashi
    1984 Volume 57 Issue 12 Pages 3593-3594
    Published: 1984
    Released: June 27, 2006
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    Equilibrium and kinetic aspects of the solvent extraction of Cu(II) with 2-(o-hydroxyphenyl)benzothiazole have been carried out using a water–chloroform system. The complex extracted into chloroform was greenish-brown in color and the absorbance at 490.0 nm obeyed Beer’s law up to 2×10−4 mol/dm3. The complex was 1 : 2 (Cu2+ : ligand) type and the over-all stability constant, β2, was 1.3×1017 at an ionic strength of 0.3. The extraction constant, Kex, was 2.5×10−8. The extraction kinetics were first order with Cu(II) ions and the reagent anions. The rate constant for the reaction was found to be 5.0×109 mol−1 min−1.
  • Yoshio Koike, Toshio Takayama, Masatoshi Watabe
    1984 Volume 57 Issue 12 Pages 3595-3596
    Published: 1984
    Released: June 27, 2006
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    The phosphorus-31 nuclear magnetic resonance spectra of [Co(acac)2(P-P)]+(P-P=diphosphine ligand) of the Werner type were measured, and the coordination chemical shifts were compared with those of complexes studied before. The coordination chemical shifts of the five-membered chelate ring were twice as much as those of the six-membered ring.
  • Shizuaki Murata
    1984 Volume 57 Issue 12 Pages 3597-3598
    Published: 1984
    Released: June 27, 2006
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    1,1′-Oxalyldiimidazole, -1,2,4-triazole, and -1,2,3,4-tetrazole were prepared in situ from oxalyl dichloride and corresponding 1H-azoles. The 1,1′-oxalyldiazoles converted carboxylic acids and their salts into 1-acylazoles.
  • Satoshi Inagaki
    1984 Volume 57 Issue 12 Pages 3599-3600
    Published: 1984
    Released: June 27, 2006
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    The regioselectivity of such fundamental organic reactions as electrophilic addition to olefins, Diels-Alder cycloaddition, and electrophilic aromatic substitution, can be explained by the phase continuity-discontinuity properties of orbitals involved in cyclic interaction for acyclic delocalization of electrons.
  • Nobumasa Kamigata, Kazutoshi Yamamoto, Osamu Kawakita, Kiyoyuki Hikita ...
    1984 Volume 57 Issue 12 Pages 3601-3602
    Published: 1984
    Released: June 27, 2006
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    Thermolysis of trifluoromethanesulfonyl azide in solvents composed of 1:1 mixtures of benzene and substituted benzenes gives trifluoromethanesulfonanilide and substituted trifluoromethanesulfonanilides. The isomer ratios, the total rate ratios, and the partial rate factors for the sulfonamidation have been determined. By the intramolecular and intermolecular selectivities, the reaction mechanism involving trifluoromethanesulfonyl nitrene intermediate is discussed.
  • Shinkiti Koto, Kazuhiro Takenaka, Naohiko Morishima, Akiko Sugimoto, S ...
    1984 Volume 57 Issue 12 Pages 3603-3604
    Published: 1984
    Released: June 27, 2006
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    Cotrolled benzylation of methyl α-D-mannopyranoside with benzyl chloride and LiOH selectively gave the 2,3,6-tribenzyl ether in a 53% yield. Such a reaction using benzyl chloride and KOH afforded mainly the 2,4,6-tribenzyl ether in a 41% yield. The products were allylated and then hydrolyzed to give the corresponding 1-OH derivatives.
  • Toshifumi Miyazawa, Takashi Yamada, Shigeru Kuwata
    1984 Volume 57 Issue 12 Pages 3605-3606
    Published: 1984
    Released: June 27, 2006
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    The alkoxycarbonylmethylation of the amide nitrogen of N-tosyl amino acid esters with iodoacetic acid esters in the presence of silver(I) oxide in N,N-dimethylformamide afforded the corresponding N-tosyl-N-carboxymethyl amino acid esters in good yields without racemization of the amino acids.
  • Seiji Yamaguchi, Kyoichi Sugiura, Reiko Fukuoka, Kazumi Okazaki, Mie T ...
    1984 Volume 57 Issue 12 Pages 3607-3608
    Published: 1984
    Released: June 27, 2006
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    2-Isopropenyl-6-methoxy-2,3-dihydrobenzofuran, prepared from m-methoxyphenol and 1,4-dibromo 2-methyl-2-butene, was converted to racemic dihydroageratone via oxidation with selenium dioxide, the acetylation with acetic acid–trifluoroacetic anhydride, and the demethylation with magnesium iodide etherate.
  • Kazuhiko Tsuchiya, Tetsuo Takemura, Nobuo Mori
    1984 Volume 57 Issue 12 Pages 3609-3610
    Published: 1984
    Released: June 27, 2006
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    In 10-substituted 3,12-dithia[4.4]metaparacyclophanes, the free energy barrier to the rotation of the para-bridged ring increases with the substituent in the order: H<F<CH3O<Cl, whereas for the flipping of the meta-bridged ring, the order of CH3O and Cl is reversed. This is discussed in terms of the steric-size anisotropy of the CH3O group.
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