Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 57 , Issue 7
Showing 1-50 articles out of 67 articles from the selected issue
  • Sigeo Fujita, Akio Takenaka, Yoshio Sasada
    1984 Volume 57 Issue 7 Pages 1707-1712
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A new compound, 9-(2-carboxyethyl)guanine, was successfully synthesized and its crystalline complex with 1-methylcytosine was prepared, in order to investigate the protein-nucleic acid interactions involving guanine base. The crystal structures of 9-(2-carboxyethyl)guanine (cx9G) and of the complex of cx9G with 1-methylcytosine (cx9G:m1C) were determined by the X-ray analysis. Crystal data: cx9G, P21/c, a=12.221(3), b=11.022(2), c=6.961(2) Å, β=100.22(2)°; cx9G:m1C, P\bar1, a=8.932(1), b=12.370(1), c=7.139(1) Å, α=85.01(1), β=99.21(1), γ=86.64(1)°. In cx9G, the carboxyl group is doubly hydrogen-bonded with N(2) and N(3) of the guanine moiety of the adjacent molecule, N(2)–H···O distance being 2.939(5) Å and N(3)···H–O 2.660(5) Å for N···O. In cx9G: m1C, the guanine moiety and 1-methylcytosine form a Watson-Crick base pair. The carboxyl group takes an O=C–OH antiperiplanar conformation and is hydrogen-bonded with N(7) of guanine in the adjacent base pair. This hydrogen bond distance is very short, 2.634(2) Å, though the unfavorable conformation of the carboxyl group. This may suggest the marked preference of the carboxyl group for N(7) of guanine in the Watson-Crick base pair. On the basis of the geometrical data found in the present crystals, some possible models of interactions were constructed and examined, for example, aspartic or glutamic acid residue in the major groove of double stranded DNA.
  • Mikio Hoshino, Shiro Konishi, Masashi Imamura
    1984 Volume 57 Issue 7 Pages 1713-1717
    Published: 1984
    Released: June 27, 2006
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    One-electron reduction by γ-ray irradiation of cobalt(III) and manganese(III) tetraphenylporphyrins (ClCo(III)TPP, ClMn(III)TPP, and IMn(III)TPP) in ethanol and MTHF(2-methyltetrahydrofuran) solutions at 77 K results in the reduction of the central metals of these porphyrins. From the optical and ESR measurements, the reduced species are found to retain the axial anion, Cl or I, in MTHF but not in ethanol. The absorption spectroscopic studies of these porphyrins in ethanol solutions indicate that the axial halide ion is displaced by an ethanol molecule prior to γ-ray irradiation.
  • Yuji Nakamura, Atsushi Aruga, Izumi Nakai, Kozo Nagashima
    1984 Volume 57 Issue 7 Pages 1718-1722
    Published: 1984
    Released: June 27, 2006
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    The crystal structure of a new synthetic compound with the composition of TlInSiS4 has been determined. The crystal is orthorhombic, and the space group is Pbnm with Z=8. The cell dimensions are a=11.74(1), b=17.038(7), and c=7.285(3) Å. The structure was solved by the Patterson method and refined to a final R-value of 0.074 for all the observed reflections. The structure is characterized by a sheet structure built up from alternating infinite(InS3)n chains and dimeric Si2S6groups. The Si2S6 groups consist of two SiS4 tetrahedra sharing an edge. The thallium atoms are situated between the sheets and are surrounded by nine sulfur atoms at distances between 3.293 and 3.957 Å.
  • Tetsuo Moriya
    1984 Volume 57 Issue 7 Pages 1723-1730
    Published: 1984
    Released: June 27, 2006
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    The fluorescence yield and the fluorescence lifetime of 7-ethoxycoumarins in aqueous solutions are reduced with the increase in the temperature and in the concentration of the quenching agents. The radiationless deactivation of the excited state in the absence of quenchers is temperature-dependent; its activation energy has been determined to be 32.5–34.8 kJ mol−1. The quenching reaction due to halide ions proceeds via both a diffusional and a static process. The rate constant for the diffusional process has a value of (9.7–10.2)×109 mol−1 dm3s−1 in the case of I as a quencher. The static quenching component can be approximately described by the V[Q] expression, with the static quenching constant, V, being 1.6–1.8 mol−1 dm3. The quenching efficiencies that represent the probability leading to real quenching reactions by an encounter of the molecule and the halide ion are unity for I, 0.39–0.42 for Br, and almost zero for Cl. The possible physical interpretation of the quenching mechanism is discussed in relation to the electron transfer between colliding species.
  • Katsuaki Shimazu, Hideaki Kita
    1984 Volume 57 Issue 7 Pages 1731-1734
    Published: 1984
    Released: June 27, 2006
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    Saw-toothed distributions of deuterium are observed in butenes produced by the deuteration of 1,3-butadiene on Pt/Al2O3 catalysts suspended in 0.5 M D2SO4. The nature of the saw-tooth is sensitive to the purity of the solution and to the deuterium content of the solution. On the basis of the N-profiles (the distributions of hydrogen equilibrated with surface H/D pool) deduced from the observed distributions of deuterium in butenes, the saw-tooth distribution is explained by the reaction mechanism where cis- and trans-1-methyl-π-allyls are reaction intermediates for the formation of cis-2-butene and the other isomers of 1-and trans-2-butenes respectively.
  • Isao Kamiya, Takashi Sugimoto, Kuniaki Yamabe
    1984 Volume 57 Issue 7 Pages 1735-1739
    Published: 1984
    Released: June 27, 2006
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    9-Methyl- (1a), 9-benzyl- (1b), 9-(diphenylmethyl)- (1c), and 9-ethylacridine (1d) were employed to obtain luminescent features of the acridines. The decay of chemiluminescence (CL) exhibits a pseudo-first order behavior with apparent rate constants 0.10, 3.30, 4.10, and 0.07 min−1 at 312 K for 1a, 1b, 1c, and 1d, respectively. A relatively high CL quantum yield (6.3×10−3) is provided for 1a, in contrast to low yields for 1b, 1c, and 1d (1.5×10−6, 1.1×10−5, and 1.3×10−4, respectively). A reaction mechanism involving a cleavage of a dioxetane intermediate to give excited singlet acridone anion is plausible for the luminescent reaction. In view of the fact that several dioxetanes decompose to give excited singlet products in high yields, the CL appears to arise from a minor reaction.
  • Isao Kamiya, Shizuaki Murata, Kuniaki Yamabe
    1984 Volume 57 Issue 7 Pages 1740-1744
    Published: 1984
    Released: June 27, 2006
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    In base-catalyzed air oxidation of substituted phenylpyruvic acids, an excited singlet product is generated from 3,5-dichloro-4-hydroxyphenylpyruvic acid (1) but excited triplet products from 3,5-dichlorophenyl-(2) and 3,5-dichloro-4-methoxyphenylpyruvic acid (3). According to the reaction scheme proposed, the singlet chemiexcitation yield from 1 and the triplet yields from 2 and 3 are 1·2×10−4, 8.3×10−4, and 6.7×10−4, respectively. A discussion is made on the difference in spin state selectivity between 1 and 2 or 3.
  • Osamu Ito, Minoru Matsuda
    1984 Volume 57 Issue 7 Pages 1745-1749
    Published: 1984
    Released: June 27, 2006
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    The spin-trapping rates for the reactions of para-substituted phenylthiyl radicals with nitrones have been determined by flash photolysis. For the phenylthiyl radical, the rate constant (in mol−1 dm3s−1) in benzene for a cyclic nitrone, 5,5-dimethyl-1-pyrroline N-oxide, is 5.2×108, which is greater than that for acyclic one, N-t-butyl-α-toluenimine N-oxide (1.1×107). The rates decrease with the solvent polarity and with the hydrogen-bonding ability; the maximum ratio of ca. 30 is observed for the rates between cyclohexane and methanol. Combined with the observed substituent effects, the mechanisms of the reactions and properties of the transition states are discussed.
  • Keiko Nishikawa, Takao Iijima
    1984 Volume 57 Issue 7 Pages 1750-1759
    Published: 1984
    Released: June 27, 2006
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    The procedure of the analysis of the diffraction intensity of liquids obtained by the energy-dispersive method has been revised and improved. A new method for determining the energy spectrum of the primary beam is presented. The escape correction, the slit correction and the correction for multiple scattering have been newly applied. Scattering of X-rays from liquid CCl4 has been measured and its structure function has been obtained by an improved procedure.
  • Atsushi Terahara, Hiroaki Ohya-Nishiguchi, Noboru Hirota, Hiroshi Awaj ...
    1984 Volume 57 Issue 7 Pages 1760-1765
    Published: 1984
    Released: June 27, 2006
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    The ESR spectra of the cation radicals of TTF and its related compounds in which two 1,3-dithiole rings are connected by conjugated carbon and cumulene chains are measured. The spin distributions obtained from the hfcc due to the protons and sulfur atoms agree well with the results of the MINDO/3 calculations. The spin densities on the sulfur and central carbon atoms decreases as the central chain length increases. A linear relationship, g=2.00379+0.00108 a(S), between the g-values and the sulfur hfcc is noted and explained in terms of the Stone’s theory. The g-values of the cation radicals with cumulene chains deviate from this relation and a possible cause is suggested.
  • Masataka Moriyasu, Kazuko Kawanishi, Atsushi Kato, Yohei Hashimoto
    1984 Volume 57 Issue 7 Pages 1766-1770
    Published: 1984
    Released: June 27, 2006
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    The restricted rotation about the carbon–nitrogen bond of formanilide has been investigated by high-performance liquid chromatography. At lower temperatures, two peaks corresponding to two dynamic rotamers (E- and Z-form) have appeared on chromatograms, whereas at higher temperatures they have not been separated and a single peak has appeared on chromatograms, due to rapid bond rotation. The equilibrium concentration ratio of E- to Z-form has been found to vary in different solvents, suggesting the presence of solute–solvent and solute–solute interactions such as hydrogen bond formation. Determination of kinetic characteristics such as rate constant and activation energy of fast reactions has been established by high-performance liquid chromatography. The authors have named the present method “dynamic high-performance liquid chromatography,” in imitation of “dynamic nuclear magnetic resonance spectroscopy” which traces fast equilibrium.
  • Kiwamu Yamaoka, Manabu Asato, Koichiro Matsuda, Kazuyoshi Ueda
    1984 Volume 57 Issue 7 Pages 1771-1776
    Published: 1984
    Released: June 27, 2006
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    A Pulsed electric linear dichroism (ELD) apparatus is described for studying the optical properties and solution conformation of biologically important macromolecules whose chromophores absorb light in the far ultraviolet region. This apparatus is capable of generating a rectangular-wave electric pulse field with a duration of 5 μs–5 ms and an amplitude of 0.2–8 kV over the 360–185 nm region. A special feature to this apparatus is its ability to record both parallel and perpendicular dichroism signals simultaneously and independently. To prove the instrumental performance, some dichroic spectra of calfskin collagen solution (pH 3.16 and concentration 0.03 g dm−3) in 0.001 mol dm−3 H3PO4 were measured in the 230–187 nm region, where the peptide chromophore shows a broad absorption spectrum. The reduced dichroism of collagen was positive but not constant throughout the wavelength region. A detailed analysis revealed that the peptide spectrum contains three overlapping absorption bands centered at 219, 200, and 189 nm. These transition moments were found to be inclined at ±(50.6–51.0°) (219 nm), ±(48.8–49.5°) (200 nm), and ±(56.0–55.8°) (189 nm) relative to the orientation axis of a triple-stranded collagen helix.
  • Kazuhiko Kandori, Akio Kazama, Kijiro Kon-no, Ayao Kitahara
    1984 Volume 57 Issue 7 Pages 1777-1783
    Published: 1984
    Released: June 27, 2006
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    The dispersion stability of needlelike and octahedral iron(III) oxides of magnetic or nonmagnetic particles in cyclohexane solutions of sodium 1,2-bis(2-ethylhexyloxycarbonyl)ethanesulfonate (Aerosol OT or AOT) was studied on anhydrous and hydrous systems. The dispersion stability of the anhydrous system was examined for seven kinds of oxides. The sedimentation velocity of dispersions, the histograms of particle distribution, the adsorption of Aerosol OT on the particles and zeta potential were measured. Potential energies of the interaction between a pair of particles were calculated for the anhydrous system. It was suggested from the calculation of potential energies that the magnetic attractive force, which is a function of the strength of the saturation magnetization and the volume of particle, is a main factor affecting the flocculation of the magnetic particles in cyclohexane as well as in 2-butanone reported in the previous papers. The study of the dispersion stability of the hydrous system was done for three kinds of needlelike oxides. The relatively stable region appeared in the lower concentration range of water. The stability decreased at the fixed water concentration followed by marked flocculation (“floc formation” region). It was considered that the appearance of the “floc formation” is caused by the formation of thick hydration layer on the oxide surface and the decrease of zeta potential.
  • Shunji Katsumata, Haruo Shiromaru, Toshiaki Kimura
    1984 Volume 57 Issue 7 Pages 1784-1788
    Published: 1984
    Released: June 27, 2006
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    For the first three ionized states of ozone the ordering of 2A1, 2B2 and 2A2 states has so far been controversial both experimentally and theoretically. The present work establishes assignment of the 2A2 state by using the characteristic of electron energy dependence of an asymmetry parameter (β) of photoelectron angular distribution measured with NeI, HeI, and NeII resonance radiation. From measurements of photoelectron spectra of ozone with NeI, HeI, and HeII radiation, we newly find that two bands centered at 16.50 and 17.6 eV exhibit vibrational structures with the spacings of about 850 and about 1000 cm−1, respectively. Furthermore abnormally weak bands are also confirmed at 22.7, 24.1, and 26.8 eV in the Hell spectrum.
  • Makoto Isihara
    1984 Volume 57 Issue 7 Pages 1789-1794
    Published: 1984
    Released: June 27, 2006
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    A simple method of estimating ionization energies is proposed, formulation being made for atomic systems. The method aims at improving Koopmans’ approximation by incorporating a scale factor into Koopmans’ variation problem for the hole state in the space built of the occupied Hartree-Fock manifold of the parent state. The shrinking of the electronic cloud through ionization is effectively taken into account with the scale factor; the scaling makes the hole state fulfil the virial theorem. Numerical examples are given for valence-shell and core ionizations of several atomic systems. The results are encouraging on the whole. The attendant concepts, the quasiparticle ejection energy and the global correction, seem to be helpful in understanding the electronic behavior through ionization.
  • Mutsuyoshi Matsumoto, Sumio Shinoda, Hiroshi Takahashi, Yasukazu Saito
    1984 Volume 57 Issue 7 Pages 1795-1800
    Published: 1984
    Released: June 27, 2006
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    Carbon-13 nuclear magnetic relaxation times of 13C-enriched benzene have been determined in order to elucidate the adsorption properties of PILM (pillar interlayered montmorillonite) by varying temperatures and coverages. The activation energy of diffusion as small as 6.5 kJ mol−1 indicates that the majority of PILM adsorption sites exhibits a weak interaction with benzene. The pre-exponential factor of correlation time was exceptionally large, probably because the two-dimensional pore structure of PILM, in contrast to the three-dimentional zeolite or the open surfaces of graphitized carbon black and silica gel, restricts the chance for the adsorbate to diffuse. In the spin-lattice relaxation spectra at low temperatures, the internal and the external surfaces of PILM were discriminated, since the two adsorbed states on these surfaces give different T1 and chemical shift values.
  • Takashi Kakiuchi, Mitsugi Senda
    1984 Volume 57 Issue 7 Pages 1801-1808
    Published: 1984
    Released: June 27, 2006
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    The theory of liquid ion-exchange membrane ion-selective electrodes has been developed on the basis of the concept of the zero-current potential, or the mixed potential in the presence of interfering ions, of ion transfer at the interface between a liquid membrane and a sample solution. Under the assumptions of the reversible ion transfer at the interface, the presence of supporting electrolytes in both phases, and the monovalency of all relevant ions, theoretical equations for the mixed potential are derived for two cases; the primary and interfering ions have 1) the same charge sign and 2) the opposite sign. The selectivity coefficients of the ion-selective electrodes can be expressed as a function of the difference between the standard ion-transfer potentials of the primary and interfering ions, the ratios of the mass-transfer coefficients of the ions, and the ratios of the concentrations of the ions. The theoretical prediction has been shown to be applicable to an interpretation of the response of liquid-membrane ion-selective electrodes.
  • Yukio Koizumi, Hiroshi Sawase, Yasuo Suzuki, Toshio Takeuchi, Mamoru S ...
    1984 Volume 57 Issue 7 Pages 1809-1817
    Published: 1984
    Released: June 27, 2006
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    Two types of lanthanoid(III) m-hydroxybenzoates, indicated in the title, have been synthesized, and the crystal and molecular structures of four representative complexes, where M=La (1), Nd (2), Sm (3), and Er (4), were determined by the single-crystal X-ray diffraction method. They are all triclinic, space group P\bar1, and the cell constants are as follows: (1) a=12.351(11), b=15.533(10), c=9.250(4) Å, α=109.86(4), β=101.40(6), γ=62.95(6)°; (2) a=12.287(4), b=15.542(7), c=9.194(3) Å, α=109.64(3), β=101.46(3), γ=62.83(3)°; (3) a=10.580(1), b=12.006(5), c=10.105(2) Å, α=111.14(2), β=90.27(1), γ=97.16(2)°; (4) a=10.586(4), b=11.943(6), c=10.027(5) Å, α=111.11(3), β=90.53(4), γ=97.26(4)°. The final R values obtained were (1) 0.039, (2) 0.038, (3) 0.030, and (4) 0.039. The central metal atoms of both types of complexes are octa-coordinated, and each is in a square-antiprism geometry. In 1 and 2, one free acid molecule is present, and the molecule is hydrogen-bonded to the oxygen atoms of the coordinated water molecules through its carboxyl oxygen atoms. 1 and 2 have linear polymeric structure, and each pair of the metal atoms is bridged by a pair of the carboxylate ligands, while 3 and 4 have a dimeric structure, where metal atoms are bridged by two carboxylate ligands.
  • Setsuko Kinoshita, Hisanobu Wakita, Isao Masuda
    1984 Volume 57 Issue 7 Pages 1818-1822
    Published: 1984
    Released: June 27, 2006
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    Thermodynamic and kinetic characterizations were carried out on the thermal, pyridine liberation-anation reactions, [CoIII(R,CH3-dioxH)2(py)2]I \oversetΔ→ [CoIII(R,CH3-dioxH)2(py)I]+py↑.* These occurred endothermally in the solid state of the complexes. The ΔH values of the reactions were determined. A large increment in the entropy was found to be indispensable for the progress of the reactions; it could be brought about by the liberation of gaseous pyridine from the solid system of the complexes. The kinetic analyses revealed that the reaction rates were increased by the substitution of R with the longer-carbon-chain alkyl groups. The activation enthalpies and activation free energies were shown to be decreased by the above substitutions. The CoIII-pyridine bond was observed to be weakened by the electron-donating inductive effect of R to the central cobalt atom and by the steric interference of R toward axial pyridine coordination.
  • Masataka Moriyasu, Yohei Hashimoto
    1984 Volume 57 Issue 7 Pages 1823-1827
    Published: 1984
    Released: June 27, 2006
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    The stepwise complex formation of the nickel(II) ion (M2+) with 2,2′-bipyridine(bpy) and 1,10-phenanthroline(phen) (Mn−12++L\ ightleftharpoonsMLn2+ with Kn=[MLn2+]/[MLn−12+][L], where n=1–3), has been investigated by means of high-performance liquid chromatography. Peaks of the labile partially ligand substituted complexes, ML2+ and ML22+, have appeared on chromatograms, along with peaks of the ML32+ and excess free ligands, on reverse phase ion-pair chromatography using sodium dodecyl sulfate in acidic media. Each labile species has been found to be eluted without any noticeable change, such as ligand addition, dissociation, or disproportionation, during chromatography. Thus, the chromatograms obtained have directly indicated the equilibrium concentrations of each species in the solutions prior to chromatography. The stepwise complex formation constants of nickel(II) with bpy or phen have been determined by means of high-performance liquid chromatography.
  • Yoshikazu Fujita, Itsuo Mori, Shoko Kitano, Hiroshi Kawabe, Yoshiyuki ...
    1984 Volume 57 Issue 7 Pages 1828-1832
    Published: 1984
    Released: June 27, 2006
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    A color reaction of purine bases utilizing a ternary-complex system among a purine base, a metal ion, and a xanthene dye was studied, and the fundamental conditions for the spectrophotometric determination of purine bases(as adenine) with eosin and silver(I) were established. The absorption maxima of the ternary-complexes lie at 550–560 nm against water. The optimum pH ranges for the color formation of the complexes are pH 4.8–5.4. Beer’s law is obeyed over the range of 1–10 μg/10 cm3 of adenine, and the apparent molar absorptivity is 1.1×105 dm3 mol−1cm−1 at 560 nm. In the determination of adenine, the coexistence of pyrimidine bases, such as uracil and cytosine, and nucleotides containing adenine, such as 5′-adenosine triphosphate(ATP) and β-nicotinamide–adenine dinucleotide(NAD), scarcely interfere.
  • Taro Tsubomura, Shigenobu Yano, Koshiro Toriumi, Tasuku Ito, Sadao Yos ...
    1984 Volume 57 Issue 7 Pages 1833-1838
    Published: 1984
    Released: June 27, 2006
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    The synthesis and crystal structure of the complex [Ni(en)(L-sor-en)]Cl2·1/2CH3OH which was derived from the reaction of tris(ethylenediamine)nickel(II) dichloride dihydrate with L-sorbose are described. Crystal-lographic details for the complex are follows: space group C2 (monoclinic); a=17.862(2) Å, b=8.212(1) Å, c=12.644(2) Å, β=90.89(1)°; Z=4; Dcalcd=1.53 gcm−3. The structure was solved by heavy atom methods, and the structure parameters including almost all hydrogen atoms were refined by least-squares methods. The final R factor was 0.032 for 2680 independent reflections. The nickel atom is octahedrally coordinated with a bidentate ethylenediamine and a tetradentate glycosylamine ligand of L-sor-en. L-Sorbose moiety adopts the six-membered α-2C5 chair conformation. In addition to the synthesis and structure of this complex, we report the results of absorption and circular dichroism spectroscopy.
  • Hiroki Haraguchi, Mohammad Abdullah, Tetsuya Hasegawa, Masao Kurosawa, ...
    1984 Volume 57 Issue 7 Pages 1839-1843
    Published: 1984
    Released: June 27, 2006
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    A preliminary study on analytical performances of graphite sample cups is described for an instrumental assembly to carry out microliter volumes of liquid sample analysis. The graphite cup with a graphite rod and an insulating handle is inserted axially via the injector tube of a quartz torch into a low power operated inductively coupled argon plasma. Univariate search method has been employed for optimization of cup size, rod height and plasma operating parameters for manganese ionic line at 257.6 nm to obtain the most favorable net signal-to-background ratio. Detection limits, reproducibilities and dynamic ranges are also reported for manganese, zinc, lead, chromium, and nickel in solution.
  • Takeo Ohsaka, Hisao Yamamoto, Masao Kaneko, Akira Yamada, Michiko Naka ...
    1984 Volume 57 Issue 7 Pages 1844-1849
    Published: 1984
    Released: June 27, 2006
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    A “heterogeneous” electron-transfer process of three kinds of viologen polymers, i.e., N,N′-dimethyl-4,4′-bipyridinium (methylviologen, MV)–NafionR, poly(xylylviologen) (PXV)-poly(p-styrenesulfonate) (PSS) and poly(methylviologen) (PMV), in which MV and PXV were electrostatically trapped in Nafion and PSS, respectively, on a basal-plane pyrolytic graphite (BPG) electrode and PMV was directly attached to the BPG electrode surface, was examined by normal pulse voltammetry. The relevant kinetic parameters (i.e., the standard rate constant, koel and the cathodic transfer coefficient, α) of the electrode reaction and the apparent diffusion coefficients, Dapp, for the “homogeneous” charge transport within these polymer films were determined at the various surface concentrations (ΓMV2+ in units of mol cm−2) of viologen dication site. With the PMV and PXV–PSS systems, both koel and Dapp were independent of ΓMV2+, while with the MV–Nafion system both koel and Dapp decreased with an increase in ΓMV2+ under the constant concentration of Nafion. The values of α were independent of ΓMV2+ and constant (i.e., 0.56, 0.58, and 0.20 for the PMV, MV–Nafion and PXV–PSS systems, respectively).
  • Hiroshi Tanaka, Kiyoshi Isobe, Shinichi Kawaguchi, Seichi Okeya
    1984 Volume 57 Issue 7 Pages 1850-1855
    Published: 1984
    Released: June 27, 2006
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    Palladium(II) complexes of the [Pd(β-dik-O)(pyridyl)(PEt3)2] type containing an O-unidentate acetylacetonate, trifluoroacetylacetonate, or hexafluoroacetylacetonate anion and a 2-, 3-, 4-pyridyl or 6-chloro-2-pyridyl group as ligands were prepared and characterized mainly by 1H and 13C NMR spectroscopy. The acetylacetonate and hexafluoroacetylacetonate ligands in the [Pd(β-dik-O)(C5H3(6-Cl)N-C2)(PEt3)2] complexes undergo the head-to-tail donor-atom exchange reaction, to which an intramolecular mechanism is proposed.
  • Yoshinori Kitaoka
    1984 Volume 57 Issue 7 Pages 1856-1858
    Published: 1984
    Released: June 27, 2006
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    Comparison of the experimental zone mobility-pH curves of nucleic acid bases with the calculated ones was made over acidic and basic regions using a pure cellulose paper as a support after correction of the capillary action and the endoosmotic flow. The mobilities in the acid region agreed with the calculated ones but those in the basic region did not. Some unknown factors affect the mobilities in the basic region.
  • Tadashi Sekiya, Tetsuo Yamamoto, Yasuyoshi Torii
    1984 Volume 57 Issue 7 Pages 1859-1862
    Published: 1984
    Released: June 27, 2006
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    The title compound with an ordered monoclinic (pseudotetragonal) perovskite structure has been prepared. The lattice constants are a=5.5239(5), b=5.5253(4), c=7.8936(6) Å, β=90.16(1)°, and Z=2. The superstructure was found to be due to a layer-like ordering of Na+ and La3+ ions along alternate c-planes as well as a NaCl-type ordering of Mg2+ and W6+ ions in the octahedral sites. This new compound is the first example for the occurence of cation ordering in the A site. The origin of the superstructure was discussed.
  • Takeshi Takeda, Hiroyuki Furukawa, Mizue Fujimori, Kouichi Suzuki, Too ...
    1984 Volume 57 Issue 7 Pages 1863-1869
    Published: 1984
    Released: June 27, 2006
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    An improved procedure for the preparation of 1-(methylthio- and phenylthio)vinyllithium reagents utilizing 2-methoxyalkyl sulfides was developed and their reactions with ketones, aldehydes, oxiranes, and alkyl halides were studied.
  • Morio Suzuki, Eiji Yamazaki, Fumiaki Takabe, Motonobu Morioka, Hideo M ...
    1984 Volume 57 Issue 7 Pages 1870-1875
    Published: 1984
    Released: June 27, 2006
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    On irradiation in benzene under oxygen atmosphere cis- and trans-4-flavanols gave flavanones with significant structural effects on the yield: A high cis/trans selectivity and enhancement effect by electron-donating substituents. A series of benzylic-type alcohols showed similar substituent effects. The structure-reactivity relationships were explained in terms of the stereoelectronic requirements for favorable overlapping of intermediates. In order to infer the active oxidant species, the above photoreactions were compared with the oxidations by singlet oxygen and superoxide ion. The involvement of superoxide ion or its related species such as electron transfer complex R···O2−· was suggested. The effects of additives and solvents were also investigated.
  • Osamu Takazawa, Kunio Kogami, Kazuo Hayashi
    1984 Volume 57 Issue 7 Pages 1876-1881
    Published: 1984
    Released: June 27, 2006
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    Enamines, prepared readily from various carbonyl compounds, react with acetals or trialkyl orthoformates in the presence of Lewis acids such as BF3·OEt2 to give corresponding β-alkoxy carbonyl compounds or α-dialkoxymethyl carbonyl compounds in good yields. The reaction of dienamines with acetals or trialkyl orthoformates also selectively gives corresponding β,γ-unsaturated α-(α-alkoxyalkyl) carbonyl compounds or β,γ-unsaturated α-diakoxymethyl carbonyl compounds in good yields.
  • Toru Sugiyama, Yukari Kusano, Kazuya Yagi, Yoko Ito, Akira Sugimori
    1984 Volume 57 Issue 7 Pages 1882-1886
    Published: 1984
    Released: June 27, 2006
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    The UV-irradiation of methyl 4-pyridinecarboxylate (1) in methanol under oxygen in the presence of sulfuric acid brings about methoxylation at the 3-position of the pyridine ring, while under nitrogen methoxylation and hydroxymethylation occur at the 2-position. The change of photoreactions of 1 caused by oxygen can not be explained either by the promotion of intersystem crossing by O2 or by the charge transfer interactions between 1 and O2.
  • Kentaro Takagi, Naomi Hayama, Ken Sasaki
    1984 Volume 57 Issue 7 Pages 1887-1890
    Published: 1984
    Released: June 27, 2006
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    Bis(trialkylphosphine)nickel(0) generated in situ from bis(trialkylphosphine)nickel(II) chloride was found to be an effective catalyst for a homo-coupling of aryl, alkenyl, or heteroaromatic halides with zinc powder. The catalytic reaction proceeded very well in NMP or HMPA solvent under mild conditions to afford dehalogenative-coupling products in good yields.
  • Yukihisa Fujita, Yukinao Noda
    1984 Volume 57 Issue 7 Pages 1891-1896
    Published: 1984
    Released: June 27, 2006
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    The thermal denaturation of ribonuclease A in aqueous solutions of 2-methyl-2,4-pentanediol(MPD) was investigated by differential scanning calorimetry at pH 5.8, i.e., conditions similar to those used to crystallize the protein, and also at pH 3. A two-state reversible denaturation occurred in aqueous MPD up to 50%(v/v) MPD. Under both conditions the denaturation temperature, Td, decreased almost linearly with increasing MPD concentration; there was a slightly greater effect at pH 5.8. The calorimetric enthalpy, ΔHd, first increased with increasing MPD concentration and then decreased slightly at MPD concentrations above 20–30%. This behavior is analogous to that observed for organic additives, such as ethanol and dimethyl sulfoxide, with denaturing agents. The plot of ΔHd against ΔSd, the denaturation entropy at Td, gave a linear correlation between these parameters, indicating a close relationship between the MPD-induced unstabilization of the protein and the water structure around the protein molecule. The standard thermodynamic parameters for denaturation, ΔG°, ΔH°, and ΔS°, were calculated from Td and ΔHd, assuming a constant heat capacity change. The unstabilizing effect of MPD on the thermal stability of the protein results from that the increase in ΔH°, induced by MPD, is compensated by a large increase in ΔS°, with a resulting decrease in ΔG°; it is in accord with an effect on solvent ordering around the exposed nonpolar groups of the protein. It also indicates a temperature dependence of the MPD effect on the protein stability.
  • Takamichi Yamagishi, Masanobu Yatagai, Hidetoshi Hatakeyama, Mitsuhiko ...
    1984 Volume 57 Issue 7 Pages 1897-1901
    Published: 1984
    Released: June 27, 2006
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    (−)-DIOP was modified in two ways: i), Introduction of a large aromatic substituent at the dioxolane ring of (−)-DIOP and ii), replacement of one diphenylphosphino group by diarylphosphino group to give unsymmetrical DIOPs. Modification at the dioxolane ring had a small effect on the asymmetric induction by DIOP in the hydrogenation. Modification at the phosphino group affected the stereocontrol by the ligand and the unsymmetrical DIOP with di-2-naphthylphosphino group gave higher optical yields than (−)-DIOP for the hydrogenation of α-acetamidocinnamic acid and dehydrodipeptides.
  • Susumu Ohira
    1984 Volume 57 Issue 7 Pages 1902-1907
    Published: 1984
    Released: June 27, 2006
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    (±)-Methyl 3-ethyl-4-oxotricyclo[4.3.0.01,5]nonane-5-carboxylate (4), prepared by the stereoselective alkylation of methyl 4-oxotricyclo[4.3.0.01,5]nonane-5-carboxylate, was reduced with zinc borohydride, and the resultant hydroxy ester was treated with p-toluenesulfonyl chloride to give a mixture of α,β-unsaturated esters, having hydrindan skeletons. The mixture was submitted to hydroboration-oxidation to afford a keto ester, which was hydrolyzed to (±)-coronafacic acid (2). A diastereomeric mixture of l-menthyl 3-ethyl-4-oxotricyclo[4.3.0.01,5]nonane-5-carboxylates, prepared by a modification of the synthesis of (±)-4, was resolved by column chromatography on silica gel, and each diastereomer was converted into (+)-2 and (−)-2 in a similar way as (±)-2.
  • Haruo Ogawa, Hideharu Fujinami, Kazuo Taya, Shousuke Teratani
    1984 Volume 57 Issue 7 Pages 1908-1913
    Published: 1984
    Released: June 27, 2006
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    Heteropoly acid (HPA) was used as an oxidant in the Wacker catalyst system. Among the catalyst systems examined, the PdSO4–H3PMo6W6O40 catalyst system showed the highest activity with regard to the oxidation of cycloolefins, particularly cyclopentene and cyclohexene, to the corresponding cyclic ketones. The largest total turnover number with respect to Pd2+ was found to be 85 in water containing 20% N-methylformamide by volume. The initial rate of cyclohexene oxidation was expressed as
    Vo=k[Cyclohexene]1.0[PdSO4]1.0[HPA]0[O2]0.
    The rate-determining step was suggested as being where cyclohexene was oxidized to cyclohexanone by Pd(II) salt. The apparent activation energy was 7.8 kcal mol−1 (1 cal=4.18 J). In the catalytic oxidation of cycloolefins (CnH2n−2: n=5, 6, 7, and 8), the yield of alicyclic ketone decreased as the carbon number n increased. Methyl-substituted cyclohexenes exhibited lower reactivities than cyclohexene.
  • Kazu Kurosawa, Tetsuya Takamura, Yasunari Ueno, John F. W. McOmie, N. ...
    1984 Volume 57 Issue 7 Pages 1914-1919
    Published: 1984
    Released: June 27, 2006
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    The reaction of biphenylene with Pb(OAc)4 gave 2-substituted biphenylenes and 2,3-biphenylenedione. The reaction of 2-methylbiphenylene and 2,3-dimethylbiphenylene with Mn(OAc)3 yielded products in which the methyl substituent had been oxidized. The reaction of 2-methoxybiphenylene with Pb(OAc)4 gave 2-acetoxy-3-methoxybiphenylene and r-2,c-3-diacetoxy-2-methoxy-2,3-dihydrobiphenylene, which is the first example of a 2,3-dihydrobiphenylene. The reactions of 2-carboxy-, 2-methoxycarbonyl- and 2,7-dibromobiphenylene with Mn(OAc)3 and (in part) with Pb(OAc)4 yielded nuclear acetoxymethylated products. The conversion of r-2,c-3-diacetoxy-2-methoxy-2,3-dihydrobiphenylene into 5,10-diacetoxy-7(8H)-benzocyclooctenone was observed.
  • Seiji Takeuchi, Yoshiaki Ohgo
    1984 Volume 57 Issue 7 Pages 1920-1928
    Published: 1984
    Released: June 27, 2006
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    Chiral tertiary amines with a secondary amide group at α- or β-carbon were prepared, and an asymmetric hydrogenation of methyl 2-(acetylamino)acrylate and N,N′-dimethyl-5-benzylidenehydantoin catalyzed by achiral base-coordinated bis(dimethylglyoximato)cobalt(II)-chiral cocatalyst system was examined by using each of them as the cocatalyst. The enantiomeric excess of N,N′-dimethyl-5-benzylhydantoin reached 79.1% with (S)-N-[(R)-1-phenylethyl]-2-quinuclidinecarboxamide as the cocatalyst. Remarkable differences were observed in the enantioselectivities between the two substrates for the same cocatalysts. Discussion about the conformations of the cocatalysts and substrates led to proposed models of chirality-recognizing transition states.
  • Masaru Sato, Sinsuke Tanaka, Seiji Ebine, Sadatoshi Akabori
    1984 Volume 57 Issue 7 Pages 1929-1934
    Published: 1984
    Released: June 27, 2006
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    1,1′-Bis(2-chloroethylthio)ferrocene reacted with disodium 1,2-ethanedithiolate to give 1,4,7,10-tetrathia[10]ferrocenophane and 1,4,7,10,22,25,28,31-octathia[10.10]ferrocenophane, along with unexpected 1,4,7-trithia[7]ferrocenophane, 1,4,7,10,13-pentathia[13]ferrocenophane and 1,4,7,10,13,25,28,31,34-nonathia[10.13]ferrocenophane. The reaction of 1,1′-bis(2-chloroethylthio)ferrocene with disodium 1,3-propanedithiolate gave 1,4,-8,11-tetrathia[11]ferrocneophane. 1,1′-Bis(3-chloropropylthio)ferrocene reacted with disodium 1,2-ethanedithiolate and 1,3-propanedithiolate to afford 1,5,8,12-tetrathia[12]ferrocenophane and 1,5,8,12,24,27,31,34-octathia[12.12]ferrocenophane, and 1,5,9,13-tetrathia[13]ferrocenophane, respectively. The structural features of the above polythia[n]ferrocenophanes are also discussed on the bases of their spectral data.
  • Yoshitomi Morizawa, Akihiro Kanakura, Hajime Yamamoto, Tamejiro Hiyama ...
    1984 Volume 57 Issue 7 Pages 1935-1942
    Published: 1984
    Released: June 27, 2006
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    The ethyl vinyl ether-dibromocarbene adduct was lithiated with butyllithium at −95 °C in tetrahydrofuran. The resulting lithium carbenoid 3 was allowed to react with various electrophiles to give 1-substituted trans-1-bromo-2-ethoxycyclopropanes (1) in good yields. The trans relationship of Br and OEt groups was found particularly pertinent to the ethanolysis of 1 producing 2-substituted propenal diethyl acetal derivatives. The reaction has been applied to 1-methoxycyclohexene–dibromocarbene adducts, giving rise hereby 2-substituted 2-cyclohepten-1-one dimethyl acetals under ring enlargement. The transformation has been utilized in the synthesis of a homoterpenoid (JH-II) or a terpenoid (β-sinensal) structure by SN2′ substitution of allylic acetates with lithium dimethylcuprate(I) or iron pentacarbonyl respectively. The reaction products of 3 with aldehydes are oxidized with dimethyl sulfoxide to give cyclopropyl ketones whose ethanolysis in the presence of boron trifluoride ether complex gives β-bromo γ-keto aldehyde acetals. Debromination followed by acidic hydrolysis produces γ-keto aldehydes serving as precursors of dihydrojasmone and cis-jasmone.
  • Sotaro Miyano, Shigeru Handa, Kunitoshi Shimizu, Katsuya Tagami, Haruk ...
    1984 Volume 57 Issue 7 Pages 1943-1947
    Published: 1984
    Released: June 27, 2006
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    The copper-promoted Ullmann reaction of chiral diol diesters of 1-bromo-2-naphthoic acid induced axial dissymmetry into the newly formed 1,1′-binaphthyl bond: chiral diol, apparent net optical yield for the joining of two naphthyl units, and axial chirality induced are as follows: (S)-1,1′-binaphthyl-2,2′-diol, 71%, S; (1S,2S)-1,2-diphenyl-1,2-ethanediol, 32%, S; (1R,2R)-1,2-bis(ethoxycarbonyl)-1,2-ethanediol, 33%, S; (4S,5S)-bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane, 3.7%, R. The reaction of (R)-1,1′-binaphthyl-2,2′-diol esters of 2-halo-3-nitrobenzoic acids gave up to 85% net optical yield for the coupling; the intramolecular cyclization proceeded with virtually complete diastereoselectivity to give cyclic diester of R,R-configuration in a 42% isolated yield. This remarkable stereocontrol is ascribed to the steric requirement of the 12-membered cyclic diester structure containing rigid 1,1′-binaphthyl and 1,1′-biphenyl moiety.
  • Kenso Soai, Hidekazu Oyamada, Masako Takase, Atushiro Ookawa
    1984 Volume 57 Issue 7 Pages 1948-1953
    Published: 1984
    Released: June 27, 2006
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    The effect of solvents on the reduction of esters was examined with readily available sodium borohydride which is known to be incapable of reducing such functional groups. In mixed solvents of t-butyl alcohol–methanol or tetrahydrofuran–methanol, various carboxylic esters and lactones were found to be reduced by sodium borohydride to the corresponding alcohols or diols in high yields. Slow addition of methanol to the refluxing mixture of ester and sodium borohydride in t-butyl alcohol or tetrahydrofuran was essential to achieve effective reduction. On the other hand, each individual solvent, methanol or t-butyl alcohol, was not effective for the reduction. The procedure provided a practical method for the functional group selective reduction of esters in the presence of chloro, cyano, carboxylato, carbamoyl, carboxy or nitro groups, which can not usually be performed by lithium aluminium hydride.
  • Tadashi Kikukawa, Motomasa Imaida, Akira Tai
    1984 Volume 57 Issue 7 Pages 1954-1960
    Published: 1984
    Released: June 27, 2006
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    In order to establish the stereochemistry of the sex attractant of various species of pine sawflies, (2S,3R,7R)-, (2S,3R,7S)- and (2S,3S,7S)-2-acetoxy- and 2-propionyloxy-3,7-dimethylpentadecane were synthesized. The alcohol moiety of each pheromone was prepared by the coupling of Grignard reagent of C12 block with tosylate of C5 block. The C12 blocks, (R)- and (S)-1-bromo-2-methylundecane, were prepared from (R)-(+)-pulegone. The C5 blocks, (2R,3S)- or (2S,3S)-2-methyl-3-tetrahydropyranyloxy-1-(tosyloxy)butane, were derived from (2S,3S)- or (2R,3S)-2-methyl-3-hydroxybutyric acid prepared by the enantio-differentiating hydrogenation of methyl 2-methyl-3-oxobutyrate over the asymmetrically modified nickle catalyst.
  • Eizo Matsumura, Hironori Kobayashi, Tomomi Nishikawa, Masahiro Ariga, ...
    1984 Volume 57 Issue 7 Pages 1961-1965
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Crystalline derivatives of the following L-amino acids modified by 3,5-dinitro-4-pyridone have been prepared: glycine, alanine, valine, leucine, isoleucine, phenylalanine, serine, threonine, tyrosine, aspartic acid, asparagine, glutamic acid, glutamine, tryptophan, histidine, arginine, methionine and lysine. The modified L-amino acids (DNPY-L-amino acids) could be purified by recrystallization and were characterized by 1H-NMR, IR and UV spectral data. The molar rotation of the DNPY-L-amino acids varied from 2 to 100 times those of the parent amino acids. The effectiveness of 3,5-dinitro-1-(4-nitrophenyl)-4-pyridone as an amino-protecting reagent of L-amino acids is described.
  • Yuichiro Haramoto, Atushi Nobe, Hiroyoshi Kamogawa
    1984 Volume 57 Issue 7 Pages 1966-1969
    Published: 1984
    Released: June 27, 2006
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    2-(p-Substituted phenyl)-5-alkyl-1,3-dithianes, new liquid crystals, were synthesized by the thioacetalization of the corresponding aldehydes and dithiols. These compounds have characteristic supercooling states, exhibit monotropic liquid crystal phases even in the case of long terminal alkyl substituents. The mesomorphic characteristics of these compounds were different from those of the corresponding 1,3-dioxanes, this must originate in the difference in the molecular width caused by the difference in the atomic volume between sulfur and oxygen.
  • Shigeru Murata, Teruo Mori, Michinori Oki
    1984 Volume 57 Issue 7 Pages 1970-1975
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A series of 1-substituted 9-(2-methyl-1-naphthyl)fluorenes, where the substituent is fluoro, chloro, bromo, or methyl, has been prepared and barriers to rotation in these compounds have been examined to investigate the substituent effects. The barrier is enhanced generally, if we go from the 1-substituent of a small size to that of a large size with an exception of the fluorine case: the 1-fluoro compound exhibits a lower barrier to rotation than the unsubstituted compound by ca. 0.5 kcal mol−1. X-Ray crystallographic analysis suggests that, in the fluoro compound, the C9(fluorene)-to-C1(naphthalene) bond is abnormally long, although other compounds possess bonds of normal lengths. The low barrier to rotation in the fluoro compound relative to the unsubstituted is thus attributed to the raise of the ground state energy and insufficient raise of the transition state energy in the former compound.
  • Kazuhisa Hiratani, Kazuhiro Taguchi, Hideki Sugihara, Kokoro Iio
    1984 Volume 57 Issue 7 Pages 1976-1984
    Published: 1984
    Released: June 27, 2006
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    Noncyclic polyethers exhibiting lithium ion selectivity have been synthesized. Their competitive alkalimetal-ion transport through liquid membranes has been investigated, and the influence of their structures on the rates and selectivities of cation transport has been demonstrated. It has been found that the introduction of the oxytrimethylene chain on the polyethers is significant for the appearance of a high selectivity for the lithium ion, and also that the kind of terminal group might play an important role either in determining the rates of cation transport or the selectivity for the lithium ion. The introduction of a methyl group at the 2-position on the quinolyl terminal group of the polyether increased largely the selectivity for the lithium ion compared with that of the polyether having an unsubstituted quinolyl group. The cause of this was discussed on the basis of the NMR spectroscopic method and the CPK-model building.
  • Tokiko Uchida, Kozo Kozawa, Takao Saito, Shinichi Motoki
    1984 Volume 57 Issue 7 Pages 1985-1989
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The crystal and molecular structures of the title compound were determined by means of X-ray diffraction. Crystal data: C16H18NS2P, Mr=319.4, triclinic, a=12.731(2), b=13.143(1), c=12.483(1) Å, α=102.39(1), β=104.34(1), γ=117.96(1)°, V=1648.6 Å3, space group P\barl, Dm=1.30, Dx=1.287 g cm−3, Z=4, μ=4.02 cm−1 (Mo Kα). The structure was solved by the direct method and refined by the block-diagonal least-squares method to R=0.082 for 4495 observed reflections. The bond distances and angles are in good agreement with the ordinary values except for the P–S–C bridged angle of 82.5°. An asymmetric unit contains two crystallographically independent molecules, which are rotational isomers along the P–C bond.
  • Tokiko Uchida, Kozo Kozawa, Takao Saito, Shinichi Motoki
    1984 Volume 57 Issue 7 Pages 1990-1993
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The crystal and molecular structures of the title compound were determined by means of X-ray diffraction. Crystal data: C26H31S3P, Mr=470.68, orthorhombic, a=17.116(4), b=19.798(4), c=14.898(3) Å, V=5048.4 Å3 (21 °C), space group Pbca, Dm=1.23, Dx=1.239 g cm−3, Z=8, μ=3.58 cm−1 (Mo Kα). The structure was solved by the direct method and refined by the full-matrix least-squares method to R=0.083 for 3318 observed reflections. The bicyclo skeleton is so highly strained that abnormal bond distances [P–C of 1.895(5) and C–C of 1.594(6) Å] were observed. Conformation of six-membered ring is a boat-form.
  • Kin-ya Akiba, Y\={u}ji Iseki, Makoto Wada
    1984 Volume 57 Issue 7 Pages 1994-1999
    Published: 1984
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    RCu·BF3 reacted with 1-ethoxycarbonylpyridinium chloride at the 4-position with almost complete regio-selectivity (>99%) to afford the corresponding 1,4-dihydropyridine derivatives in high yields (81–94%). The dihydropyridines were oxidized by oxygen to give 4-alkyl(aryl)pyridines (38–68%). Grignard reagents also reacted with 1-t-butyldimethylsilylpyridinium triflate with almost complete regioselectivity (>99%) to afford the corresponding 1,4-dihydropyridines, which were easily oxidized by oxygen to give 4-substituted pyridines in higher yields than above (58–70%).
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