Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 52 , Issue 3
Showing 1-50 articles out of 68 articles from the selected issue
  • Naoru Hamaguchi, Terumichi Nakagawa, Toyozo Uno
    1979 Volume 52 Issue 3 Pages 649-654
    Published: 1979
    Released: April 19, 2006
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    Interactions in a ternary solution of alkali metal halide–amide–glycol have been investigated on the basis of NMR measurement of chemical shifts of OH proton of glycol and amidic protons of acetamide. Measurements were carried out with various alkali metal halides (MX, M=Li, Na, K, X=Cl, Br, I) and glycols (mono-, di-, tri-, and tetraethylene glycol). The dependency of the chemical shifts on solute concentration was examined with a ternary solution of potassium iodide–acetamide–ethylene glycol. The addition of alkali metal halide to respective glycols or glycolic solutions of acetamide gave rise to a change in chemical shift values. The observed changes were related to the ionic sizes of cations and anions of alkali metal halides and to the number of oxyethylene units in a glycol molecule. It was found that a large ion induces a higher magnetic field shift of resonance positions of glycolic OH proton and amidic proton at trans position than a small ion, the magnitude of the shift change being almost proportional to the concentration of ion, and halogen anion formed in glycolic solution tending to interact with hydrogen at trans position rather than at cis position. From a comparison with the values for chemical shifts of water proton in aqueous alkali metal halide solution, it is suggested that the contribution of alkali metal halide to the chemical shift changes in glycolic solution is similar to those in aqueous solution.
  • Sadakatsu Nishikawa, Mitsuo Mashima
    1979 Volume 52 Issue 3 Pages 655-658
    Published: 1979
    Released: April 19, 2006
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    Ultrasonic absorption and velocity measurements were performed in aqueous solutions of t-butylamine and isobutylamine at 20 °C. Two relaxational absorptions were found in both solutions. One is associated with the proton transfer reaction, the rate constants being determined together with the standard volume change of the reaction. No effect was observed on Kf with change in molecular structure. The other, associated with the peak sound absorption concentration, is ascribed to the association-dissociation reaction mechanism of unionized amine molecules. The results are discussed in comparison with those of butylamine.
  • Kazuo Sueoka, Toshio Ikeda
    1979 Volume 52 Issue 3 Pages 659-663
    Published: 1979
    Released: April 19, 2006
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    An improved viscometer method has been applied to the determination of the magnetic susceptibility of a paramagnetic gas and found to be of use in the analysis of a paramagnetic gas mixed in a diamagnetic gas. The magnetic susceptibilities of oxygen and nitrogen monoxide have been determined to within ±0.5% using a saturated aqueous solution of sodium chloride as the working liquid.
  • Hiroyasu Inoue, Yukimi Hiroshima, Kiyoto Miyazaki
    1979 Volume 52 Issue 3 Pages 664-666
    Published: 1979
    Released: April 19, 2006
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    5,6-Dihydrobenzo[c]cinnoline is an intermediate in the photochemical formation of carbazole from benzole[c]cinnoline. The mechanism of the photo-induced carbazole formation from 5,6-dihydrobenzo[c]cinnoline has been studied in acidic aqueous 2-propanol of the reactant previously produced by the photo-reduction of benzo[c]cinnoline. It has been established that only the protonated species of the reactant undergoes photoreaction. The results of quenching experiments on quantum yields for the reaction and on the fluorescence of the reactant have shown that the reactive state is the first excited singlet state of protonated 5,6-dihydrobenzo[c]cinnoline. The initial step in the reaction is the hydrogen atom abstraction followed by elimination of the amino radical.
  • Hirosi Matuo, Noriaki Yosida, Kinsi Motomura, Ryohei Matuura
    1979 Volume 52 Issue 3 Pages 667-672
    Published: 1979
    Released: April 19, 2006
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    Surface pressure-area(π-A) curves of the two-component surface films of long normal chain fatty acids with ethyl hexadecanoate were measured at various compositions and temperatures. It was found that the π-A curves of the mixed monolayers vary characteristically with the number of carbon atoms of the film-forming acid. The two-dimensional phase diagrams of these systems and their partial molar enthalpy changes were obtained by taking advantage of the thermodynamic treatment of multicomponent surface films. It was concluded that the chain length of the acid plays an important role in the thermodynamic state of the mixed monolayer.
  • Hirosi Matuo, Kinsi Motomura, Ryohei Matuura
    1979 Volume 52 Issue 3 Pages 673-676
    Published: 1979
    Released: April 19, 2006
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    In order to clarify the effect of molecular structure on states and properties of mixed monolayers, surface pressure-area(π-A) curves of the two-component surface films of long normal chain fatty acids with hexadecyl acetate were measured at various compositions and temperatures. By use of thermodynamic analysis, the phase diagrams and partial molar enthalpy changes were calculated. For four systems studied in the present paper it was found that the diagram and enthalpy change vary characteristically with the number of carbon atoms of acids, but the dependence on the chain length of acid in fatty acid–hexadecyl acetate systems was very different from that in fatty acid–ethyl hexadecanoate systems.
  • Keiichi Fukuyama, Tamaichi Ashida, Yukiteru Katsube, Masao Kakudo
    1979 Volume 52 Issue 3 Pages 677-683
    Published: 1979
    Released: April 19, 2006
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    The structures of 6-deoxyversicolorin A, C18H10O6, and versicolorin A, C18H10O7, both isolated from Aspergillus versicolor, have been determined by the X-ray diffraction method. Both compounds crystallized in the space group P212121, with four molecules per unit cell. The cell dimensions of 6-deoxyversicolorin A are a=9.588, b=18.083, c=7.769 Å, and those of versicolorin A are a=9.524, b=18.629, c=7.629 Å. The structure was refined to R=0.055 for 6-deoxyversicolorin A and to R=0.043 for versicolorin A. Both structures are in agreement with those assigned by chemical and spectroscopic methods. There are two intramolecular hydrogen bonds in each molecule. Although an intermolecular hydrogen bond is present in versicolorin A, both structures are isotypic. The dimensions of the anthraquinone skeleton and the dihydrofuro[2,3-b]furan moiety are compared with those in related compounds whose structures have been determined.
  • Masaaki Sugiura, Toshio Shinbo
    1979 Volume 52 Issue 3 Pages 684-688
    Published: 1979
    Released: April 19, 2006
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    The rate of picrate transport coupled to a diffusion of potassium ions through a bulk 1,2-dichloroethane membrane has been measured. The membrane, containing a potassium ionophore separated two aqueous phases, one containing picrate and potassium salt and the other containing picrate and lithium salt. The picrate anion was accumulated against the concentration gradient in the aqueous phase containing the lithium salt. The rate of picrate transport incrased with increasing ionophore concentration and in the absence of the ionophore, the transfer of picrate did not occur. The effect of potassium and lithium counter-ions such as chloride, nitrate and sulfate on the transport of picrate has been examined. The combination of potassium sulfate and lithium nitrate showed the highest rate of transport. In the potassium nitrate-lithium nitrate system, the transport of picrate was appreciably depressed by the transfer of nitrate ions across the membrane. The decrease in concentration of potassium ion in the aqueous phase brought about a lowering of the rate of picrate transport. The rate of picrate transport rose according to the following order of ionophore : dicyclohexyl-18-crown-6>dicyclohexyl-24-crown-8>dibenzo-18-crown-6>dibenzo-24-crown-8>valinomycin.
  • Yôichi Iida
    1979 Volume 52 Issue 3 Pages 689-692
    Published: 1979
    Released: April 19, 2006
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    Such crystalline ion radical salts as Würster’s Blue perchlorate and K+ p-Chloranil\ ewdot are known to undergo phase transitions in the solid state. There are distinct differences in their optical and magnetic properties between the low- and high-temperature phases. Using Hubbard Hamiltonian, the electronic states of the high-temperature phases of those solid ion radical salts were explained in terms of an infinite non-alternant linear chain model, while those of the low-temperature phases, in terms of a dimer model.
  • Yuko Motoda, Yukio Kubota
    1979 Volume 52 Issue 3 Pages 693-696
    Published: 1979
    Released: April 19, 2006
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    The temperature dependence of long-lived emissions of Acridine Orange bound to DNA has been investigated. Only phosphorescence with a maximum close to 620 nm is observed in the range 77—ca. 150 K. With a rise in temperature, the delayed thermal fluorescence around 530 nm is observed in addition to phosphorescence at a high ratio of DNA phosphate to dye (PD). With a decrease in PD value, the delayed thermal fluorescence is replaced by a new delayed emission band around 640 nm. Its maximum wavelength is very close to that of dimer fluorescence of Acridine Orange in water. It has been shown that the emission results from two processes: (1) thermal excitation of the triplet state of the dimer to the excimer state and (2) excimer formation after the thermal excitation of the triplet state of the monomer to the first excited singlet state.
  • Katsuomi Takehira, Takashi Hayakawa, Toshio Ishikawa
    1979 Volume 52 Issue 3 Pages 697-705
    Published: 1979
    Released: April 19, 2006
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    The liquid-phase oxidation of cyclohexene has been conducted in benzene using a vanadium–chromium binary oxide supported on γ-Al2O3 or SiO2 as the catalyst. Three series of catalysts have been prepared by a kneading method using the following combinations of raw materials; NH4VO3+Cr(NO3)3·9H2O+alumina hydrate (Catalyst G), NH4VO3+(NH4)2CrO4+alumina hydrate (H), and NH4VO3+Cr(NO3)3·9H2O+silica sol (I). It has been found that the activity of the supported binary system is due to the interactions between the metal oxides and the carrier. The contributions of compounds such as the chromium isopolyvanadates appear to add to the above activity. The order of catalytic activity has been established as : I>H>G. The V2O5–SiO2 system in the I series showed the highest activity, but rapidly became depleted in the course of reaction. The second highest activity was given by Cr2O3–SiO2 system, on which Cr5+ species was observed. In both cases, the vanadium and chromium metal ions may be coordinated tetrahedrally on SiO2. The Cr2O3–Al2O3 in the H series contained Cr5+ ions and exhibited high activity which may be attributed to the tetrahedral configuration. It is thought that the tetrahedral complexes catalyze the autoxidation of cyclohexene by decomposing 1-cyclohexenyl hydroperoxide.
  • Jun Kamo, Nobuo Tanaka, Yoshiki Matsuura, Tamaichi Ashida, Masao Kakud ...
    1979 Volume 52 Issue 3 Pages 706-710
    Published: 1979
    Released: April 19, 2006
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    The structure of (R)-thiazolidine-4-carboxylic acid was refined at 111 and 293 K, respectively. Population analysis, which refines the population of the electrons in the molecule, was carried out, the result being compared with that of theoretical calculation.
  • Kinya Iijima, Shuzo Shibata
    1979 Volume 52 Issue 3 Pages 711-715
    Published: 1979
    Released: April 19, 2006
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    The molecular structure of trimethylamine-boron trifluoride (CH3)3N·BF3 was determined from gas electron-diffraction data with vibrational and rotational spectroscopic data. The geometric parameters of the molecule were found to be very close to those inferred from the preliminary analysis of the diffraction data alone. The structural parameters and uncertainties were rg(N–B)=1.674(4) Å, rg(B–F)=1.374(2) Å, rg(C–N)=1.485(2) Å, rg(C–H)=1.100(3) Å, rg(F…F)=2.288(2) Å, and rg(C…C)=2.420(4) Å. The potential barrier about the N–B axis was estimated to be 4.3±0.3 kcal/mol in the gas phase; this value is much larger than that from NMR spectra.
  • Masami Tatsumi, Takasuke Matsuo, Hiroshi Suga, Syûzô Seki
    1979 Volume 52 Issue 3 Pages 716-727
    Published: 1979
    Released: April 19, 2006
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    Heat capacities of the system of solid solutions SnCl2(H2O)x(D2O)2−x (x=2.00, 1.97, 1.75, 0.96, 0.50, 0.25, and 0.03) were measured by an adiabatic calorimeter capable of determinations of heat capacity with the temperature step of 5–10 mK. The heat capacity peak due to order-disorder change of hydrogens becomes broader and its transition temperature rises as the deuteron concentration is increased. A small first-order component was found in the crystals of x=2.00, 1.97, and 1.75. Measurements were repeated for aged crystals of x=0.96, 0.50, and 0.03. Nature of the phase transition has been discussed in analogy with the liquid-vapor critical point. From the heat capacity data around the glass transition it is concluded that the motion of the hydrogen atoms is strongly correlated with each other over a range whose size is large enough that fluctuation of the local isotopic composition from the average is negligible.
  • Masami Tatsumi, Takasuke Matsuo, Hiroshi Suga, Syûzô Seki
    1979 Volume 52 Issue 3 Pages 728-736
    Published: 1979
    Released: April 19, 2006
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    The previously published heat capacity data on Sncl2(H2O)x(D2O)2−x (x=2.00, 1.97, 1.75, 1.50, 0.96, 0.50, 0.25, 0.03) were analyzed to derive anomalous contribution due to the phase transitions that occur between 218 and 235 K depending on the isotopic composition. The phase transition is of the first-order for x=2.00, 1.97, and 1.75. The entropy discontinuities at the transitions are (0.149±0.005), (0.152±0.005), and (0.133±0.010) J K−1 mol−1, respectively, out of the total transition entropies of 3.98, 3.90, and 3.89 J K−1 mol−1. The first-order transition does not occur for the other crystals for which the heat capacity anomaly is rounded. Apparent critical exponent α of the heat capacity was calculated for all of the crystals. They are in the range from 0.43 to 0.80 and have the same value below and above the transition temperature for each of the crystals in agreement with the spatial two dimensionality of the crystal structure. No evidence was found for crossing-over to the three dimensional ordering. Change of the transitional behavior with the isotopic composition was discussed in analogy with the liquid-vapor critical phenomenon. An argument based on the crystallographic symmetry of the actual crystal and the corresponding dimer lattice was advanced for this interpretation of the unusual isotope effect.
  • Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1979 Volume 52 Issue 3 Pages 737-741
    Published: 1979
    Released: April 19, 2006
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    The molecular structure of carboxymethylpalladium(triphenylphosphine)pyridine has been determined by X-ray crystal structure analysis of its dichloromethane solvate, [Pd(C2H2O2)(PPh3)(py)]·0.6 CH2Cl2. The crystal belongs to the monoclinic system, space group P21/c, with four formula units in a cell with dimensions of a=8.791(4), b=14.623(7), c=19.862(5) Å, and β=101.53(4)°. R=0.091 for 2806 non-zero reflections. The feature of the structure is that the palladium atom is C,O-chelated by an acetic acid to form a four-membered ring [Pd–C=2.004 (16) and Pd–O=2.093 (11) Å], and the palladium atom has approximately square-planar geometry.
  • Satoshi Suzuki, Tsuneo Fujii, Shigeru Yamanaka, Nobuyuki Yoshiike, Zen ...
    1979 Volume 52 Issue 3 Pages 742-746
    Published: 1979
    Released: April 19, 2006
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    The absorption and fluorescence spectra of 1- and 2-anthroic acids (1- and 2-anthracenecarboxylic acids) in alcoholic solvents have been observed as a function of solute concentration. It was revealed that 1- and 2-anthroic acids form hydrogen-bonded dimers in their ground states. The equilibrium constants for dimer formation are : 1.2×104 mol−11 for 1-anthroic acid in methanol and 2.0×104 mol−11 for 2-anthroic acid in ethanol. Owing to dimer formation, the lowest frequency absorption band of 1-anthroic acid was uniformly displaced to the red, while that of 2-anthroic acid was distinctly resolved into two bands. The band assignment was confirmed by the method of photoselection. No excimer-type fluorescence was observed in 1- and 2-anthroic acids. The lack of mirror-symmetry relationship between the absorption and fluorescence spectra of 1-anthroic acid is explained by the geometrical relaxation in its excited state.
  • Ken Kaneko, Takashi Katsura
    1979 Volume 52 Issue 3 Pages 747-752
    Published: 1979
    Released: April 19, 2006
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    When the Mg2+/Fetotal molar ratio in the initial aqueous suspension is below 0.1 at pH 9.0 and 65 °C, almost all Mg2+ is incorporated into the spinel type ferrite by the air oxidation of Fe(OH)2. The chemical composition of the Mg-bearing ferrite thus obtained is not stoichiometric, and is expressed as the MgFe2O4–Fe3O4–γ-Fe2O3system. When the Mg2+/Fetotal ratio exceeds 0.1, the excess Mg2+ produces a basic magnesium sulfate which has a composition of [Mg1.002+, Na0.64+] [OH1.36,(SO42−)0.64]. At pH 8.0, a small amount of the Mg2+ is incorporated into the ferrite, between pH 9.0 and 10.0 only the Mg-bearing ferrite is formed, and at pH 11.0, the α-FeOOH type compound is formed together with the Mg-bearing ferrite.
  • Minahiro Okabayashi, Kozo Igi, Jinsai Hidaka
    1979 Volume 52 Issue 3 Pages 753-760
    Published: 1979
    Released: April 19, 2006
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    Five uns-cis-mer and two uns-cis-fac complexes of (trimethylenediamine-N,N′-diacetato)(L-amino carboxylato)cobalt(III) were prepared, where L-amino carboxylate denotes L-alaninate, L-valinate, L-prolinate, L-hydrogen aspartate, or L-hydrogen glutamate ion. The complexes were separated into the fourteen isomers, Δ-, Λ-uns-cis-mer for the L-alaninato, L-valinato, and textscl-prolinato complexes, and Δ-, Λ-uns-cis-mer and Δ-, Λ-uns-cis-fac for the L-hydrogen aspartato and L-hydrogen glutamato complexes. They were characterized by their proton magnetic resonance, absorption and circular dichroism spectra. Each of the uns-cis-mer and uns-cis-fac isomers showed the characteristic CD behavior in the second absorption band region. The Λ-uns-cis-mer and Δ-uns-cis-fac isomers of the L-aspartato and L-glutamato complexes were stereoselectively formed, the formation ratios of the isomers being estimated spectrophotometrically.
  • Hideaki Kanno, Kazuo Kashiwabara, Junnosuke Fujita
    1979 Volume 52 Issue 3 Pages 761-765
    Published: 1979
    Released: April 19, 2006
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    A series of chromium(III) complexes of the type, [Cr(bpdo)n(en)3−n]3+ was obtained by preparing two new complexes, n=1 and 2, where bpdo denotes 2,2′-bipyridyl N,N′-dioxide. Each of the bpdo complexes gave only one pair of enantiomers, which were resolved by an SP-Sephadex column chromatographic or a chemical method. The circular dichroism spectra of the resolved complexes were compared with those of the related complexes of the known absolute configuration. The [Cr(bpdo)3]3+ complex in water racemizes spontaneously in dark. The rate is independent of the concentrations of the complex, acid, and the free ligand, and an intramolecular racemization mechanism is suggested.
  • Shoji Nakada, Mutsuo Yamada, Tasuku Ito, Masatoshi Fujimoto
    1979 Volume 52 Issue 3 Pages 766-771
    Published: 1979
    Released: April 19, 2006
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    Reversible thermochromisms are found for about thirty kinds of metal complexes of triphenylmethane complexons in aqueous solutions. The thermochromism observed in the aqueous solution of copper(II) complex with 3,3′-bis[N,N-bis(carboxymethyl)aminomethyl]-o-cresolsulfonphthalein (Xylenol Orange, XO) was primarily ascribed to the temperature-dependence of the protolytic equilibria between a complex species AH having an uncoordinated free phenolic hydroxyl group and a complex species A having a coordinated phenolate group: AH\ ightleftharpoonsA+H. The equilibrium constant K of the reaction was determined to be p(K/mol dm−3)=4.40 at 25 °C. The thermodynamic parameters ΔH and ΔS for the reaction were calculated to be 26±2 kJ mol−1 and 1±3 J mol−1 K−1 (298 K), respectively. The rate constant of the proton dissociation of the phenolic hydroxyl group in the complex AH was estimated to be ca. 2±105s−1.
  • Kazuo Kashiwabara, Masaaki Kojima, Junnosuke Fujita
    1979 Volume 52 Issue 3 Pages 772-778
    Published: 1979
    Released: April 19, 2006
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    Four new complexes of the type, trans-[Co(CN)2(1,3-diamine)2]+ were prepared, where 1,3-diamine is (S,S)-1,3-diphenyl-1,3-propanediamine, (R,R)-2,4-pentanediamine, (S)-1,3-butanediamine, or (S)-1-phenyl-1,3-propanediamine. Two diammine complexes of the same type with (S)-1,3-butanediamine and (S)-1-phenyl-1,3-propanediamine, and trans-[Co(CN)2((R,R)-1,2-diphenyl-1,2-ethanediamine)2]+ were also newly prepared. The circular dichroism (CD) spectra of the new complexes measured in several solvents were compared with those of the corresponding dichloro and diammine complexes. The CD spectra of the dicyano complexes of (S)-1,3-butanediamine and (S)-1-phenyl-1,3-propanediamine showed remarkable solvent dependence, while those of the other complexes small or little dependence.
  • Fukumi Hirano, Shoji Wakabayashi
    1979 Volume 52 Issue 3 Pages 779-783
    Published: 1979
    Released: April 19, 2006
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    The reaction of 3- and 3,5-methyl-substituted cyclohexanones with formaldehyde in acid media has been studied. The acid-catalyzed reaction gave 2,4,12,14-tetraoxatricyclo[8.4.0.01,6]tetradecane, 2,4-dioxaspiro[5.5]undecan-7-one, and 2,4,8,10-tetraoxatricyclo[4.4.4.01,6]tetradecane derivatives. The effect of the methyl groups on the product distribution has been discussed.
  • Shinkiti Koto, Naohiko Morishima, Shonosuke Zen
    1979 Volume 52 Issue 3 Pages 784-788
    Published: 1979
    Released: April 19, 2006
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    Glucosidation of 2,3,4,6-tetra-O-benzyl-α-D-glucopyranose with methanol or cyclohexanol in the presence of chlorosilane and silver sulfonate is described. As by-products, octa-O-benzyl-α,α- and -α,β-trehaloses are also formed. Possible reaction pathways are discussed.
  • Akira Yabe
    1979 Volume 52 Issue 3 Pages 789-795
    Published: 1979
    Released: April 19, 2006
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    The photolysis of 2,3-diazidonaphthalene (3a) in a rigid matrix at 77 K gave the product having absorption bands in the 400–500 nm region, which has been assigned as α,ω-dicyano-o-xylylene (2a) by use of another precursor 1,2-dicyano-1,2-dihydrobenzocyclobutene. 2a has been also observed by the flash photolysis of 3a in fluid solution at room temperature, and the lifetime in methanol at 20 °C was 62 s. The dominating factor in the lability of 2a was the rigidity of the medium rather than the temperature. The reaction mechanism for the formation of 2a from 3a has been proposed as a monophotonic process involving the attack of the nitreno group on the azido group at the ortho position. Similarly, direct observations of α,ω-dimethoxy- and α,ω-diacetoxy-α,ω-dicyano-o-xylylenes have been given from 1,4-dimethoxy- and 1,4-diacetoxy-2,3-diazidonaphthalenes respectively.
  • Yoshikazu Isowa, Tetsuya Ichikawa
    1979 Volume 52 Issue 3 Pages 796-800
    Published: 1979
    Released: April 19, 2006
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    X–Dipeptides (X=Z, Z(OMe), or Z(3Me)) have been catalytically synthesized by several microbial metalloproteinases. Among the enzymes used, Thermolysin showed the most remarkable ability in the coupling reactions of the esters or the amides of phenylalanine, leucine, isoleucine, and valine (and methionine in the case of the amide) with various X–amino acids. This method has been applied to the syntheses of ZPhePheOMe and ZPhePeOMe on a practical scale. Ammonium sulfate and sodium chloride had a marked effect on the condensed products, increasing the yield.
  • Hideaki Tanaka, Setsuo Takamuku, Hiroshi Sakurai
    1979 Volume 52 Issue 3 Pages 801-806
    Published: 1979
    Released: April 19, 2006
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    The photochemical trans-cis isomerization of methyl 3-(1- and 2-naphthyl)acrylate (1Me and 2Me) and the intramolecular (2+2) cycloaddition of ethylene bis[3-(1- and 2-naphthyl)acrylates] (1E and 2E) have been studied in cyclohexane and methanol. The quantum yield of the trans-cis isomerization of 2Me and 2E in methanol was larger than that in cyclohexane, while the yield of the cyclization of 2E showed the reverse. The isomerization is thought to occur via the triplet state, while the cyclization is via the singlet excited state. The triplet yield of 2Me in the polar solvent has been estimated to be larger than in nonpolar solvent. The cyclization of 1E was much slower than that of 2E, and the quantum yield of the reaction of 1Me and 1E did not appreciably depends on the polarity of the solvent.
  • Fumio Ando, Jugo Koketsu, Yoshio Ishii
    1979 Volume 52 Issue 3 Pages 807-810
    Published: 1979
    Released: April 19, 2006
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    Trialkoxyarsines (I) and -stibines (II) react with sulfur dioxide to give the corresponding dialkyl sulfites and arsenic trioxide or polymeric residues containing antimony. The reactivity of the compounds (I) is very low, and the yield is poor. Reactions of I and II with selenium dioxide afford dialkyl selenites together with arsenic trioxide or the same polymeric residues containing antimony as in the case of the reaction with sulfur dioxide. The reaction followed a stoichiometry of three moles of trialkyl phosphites (III) and one mole of selenium dioxide yields a 2 : 1 molar ratio of the phosphates : the phosphoroselenoates. A similar reaction of the phosphites with selenium dioxide in a 2 : 1 stoichiometry gives the phosphates and red selenium quantitatively. The rate of oxidation of the phosphorus compounds by selenium dioxide decreases in the order Bu3P>BuP(OEt)2>P(OEt)3. Based on these results, the possible mechanisms have been discussed.
  • Kousuke Kusuda, Alfred Roedig
    1979 Volume 52 Issue 3 Pages 811-816
    Published: 1979
    Released: April 19, 2006
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    Decachloro-4-allylidenecyclopentene (6) was synthesized by the reaction of pentachlorocyclopentadiene with hexachloropropene in the presence of anhydrous aluminium chloride. Hexachloro-2-allylidene-4-cyclopentene-1,3-dione (11), prepared from 6 by treatment with coned nitric acid, cyclized to hexachloro-2,5-dihydrocyclopenta[b]pyran-5-one (14) on heating. In a solvent such as acetone and acetonitrile, 4 rearranged to hexachloro-2,5-dihydrocyclopenta[b]pyran-2-one (18) at room temperature. The mechanism of this rearrangement is discussed. Hydrolysis of 14 by 90% sulfuric acid afforded tetrachloro-2,5-dihydrocyclopenta[b]pyran-2,5-dione (15), which was obtained directly from 6 by treatment with sulfuric acid. The reactions of 11 with anhydrous methanol, and of 15 with diazomethane were investigated.
  • Akira Nomura, Yazaemon Morita, Yukitoshi Kogure
    1979 Volume 52 Issue 3 Pages 817-820
    Published: 1979
    Released: April 19, 2006
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    A simple method for the characterization of nitrogen compounds in petroleum products by the investigation of the distribution profiles of nitrogen compounds using stepwise gradient elution on silica gel has been conducted. Samples were charged onto a 8φ×150 mm glass column containing 3 g of silica gel for column chromatography, followed by 15 ml of hexane to remove the non-polar bulk hydrocarbons from the sample. The eluate collected was removed from the solvent and analyzed for nitrogen, wt % yield and UV absorbance at 220 nm. The same procedure was followed by each 15 ml of 1, 3, 5, 10, 30, 60, 100%(v/v)-THF in hexane eluents. Plots of the nitrogen contents vs. the concentration of eluents gave characteristic patterns for petroleum distillates. The crude and residual oils from different geological sources exhibit similar nitrogen distribution profiles. There are two peak values; the peak at 3%-THF increases and that at 30%-THF decreases as the boiling range of the distillate decreases. Nitrogen compounds are distributed uniformly in a wide range of polar components with regard to adsorptivity on silica gel. The method was further applied to the reaction products of quinoline and indole by irradiation with UV light in isooctane (2,2,4-trimethylpentane) solution.
  • Tohru Nishiwaki, Masao Usui, Kinji Anda, Mitsuhiko Hida
    1979 Volume 52 Issue 3 Pages 821-825
    Published: 1979
    Released: April 19, 2006
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    2,4,6-Trichlorobiphenyl and seven other chlorobiphenyls have been photolyzed in both alkaline and neutral 2-propanol in order to investigate the reactivity and selectivity towards dechlorination. Predominant dechlorination at the 2-position has been confirmed for all PCBs in neutral solution and interpreted in terms of the steric and electronic effects of the phenyl group. In the presence of alkali, however, competitive elimination between the ortho and para chlorine atoms of 2,4-dichlorobiphenyl and 2,4,6-trichlorobiphenyl occurred. The photo-dechlorination of 2,3- and 2,5-dichlorobiphenyls took place however only at the ortho position. The dechlorination ratios (ortho/para) were 7.5 and 0.8 for 2,4-dichlorobiphenyl and 2,4,6-trichlorobiphenyl, respectively. This characteristic of the ortho chlorine atom has been elucidated assuming the steric and electronic effects of the phenyl group in the radical anion. A correlation has been found between the reduction potential and the reactivity of PCB in alkaline solution. The differences in reactivity among the chlorobiphenyls has been attributed to the electron acceptabilities in the ground states.
  • Tameo Iwasaki, Hiroshi Horikawa, Kazuo Matsumoto, Muneji Miyoshi
    1979 Volume 52 Issue 3 Pages 826-830
    Published: 1979
    Released: April 19, 2006
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    α-Alkoxy α-amino acid derivatives were synthesized in good yields by anodic oxidation of acylaminomalonic acid monoesters in alcohols. Transformation of ethyl N-acetyl-α-methoxyalaninate into ethyl N-acetyl-α,βdehydroalaninate was achieved in an excellent yield by thermal treatment of the former amino acid with a catalytic amount of ammonium bromide. Substitution of the α-alkoxy group of the α-alkoxy amino acids with nucleophiles was effected by tin tetrachloride to afford the α-substituted α-amino acids.
  • Jun-ichi Hayami, Nobuhisa Hihara, Nobuo Tanaka, Aritsune Kaji
    1979 Volume 52 Issue 3 Pages 831-835
    Published: 1979
    Released: April 19, 2006
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    Secondary α-deuterium isotope effects were studied in the symmetrical nucleophilic substitution of the substituted chloromethanes in acetonitrile. The apparent second order rate coefficients show a significant isotope effect for chloromethyl aryl ethers and sulfides (1.11–1.14 per D), and an intermediate value of 1.05 for cinnamyl chlorides. 2-Arylethyl chlorides were shown to give an appreciable isotope effect of 1.03–1.04, and arylchloromethanes to give varying amount of the isotope effect from 1.006 to 1.050 depending upon the ring substituent. The deuterium label also gave rise to a significant equilibrium isotope effect on the substrate-nucleophile association in the reaction mixture. The observation of an equilibrium isotope effect suggested a possibility that an apparent isotope effect was a composite of the thermodynamic and the kinetic isotope effects. Thus the dissection resulted in a uniform and a fairly large kinetic isotope effect for all the activated substrates studied and in a small kinetic isotope effect for 2-arylethyl chloride. The results are explained in a framework of loose–tight transition state.
  • Hitomi Suzuki, Michiyo Usuki, Terukiyo Hanafusa
    1979 Volume 52 Issue 3 Pages 836-840
    Published: 1979
    Released: April 19, 2006
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    Polyalkylbenzyl thiocyanates, upon irradiation in acetic acid, readily undergo reversible photoisomerization, giving an equilibrium mixture composed mostly of the corresponding isothiocyanates. Several new bis- and tris(isothiocyanatomethyl)polymethylbenzenes have been prepared by utilizing the photoinduced multiple thiocyanate isomerization.
  • Tamotsu Yamamoto, Masa-aki Kakimoto, Makoto Okawara
    1979 Volume 52 Issue 3 Pages 841-845
    Published: 1979
    Released: April 19, 2006
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    For the preparation of S-vinylsulfilimines (1), mainly S-phenyl-N-tosyl-S-vinylsulfilimine, three routes were examined, viz., (A) the reaction of vinyl sulfide with chloramine T, (B) that of 2-haloethyl phenyl sulfide with chloramine T followed by dehydrohalogenation, and (C) that of 2-hydroxyethyl sulfide with chloramine T followed by acetylation of the hydroxyl group and deacetoxylation. Route A has disadvantages of troublesome preparation of vinyl sulfides and low yield. Route B gives the precursor sulfilimine to 1 in good yield only by use of anhydrous chloramine T. Route C gives the best results in view of starting material and yield.
  • Hiroyoshi Kamogawa, Yuichiro Haramoto, Masato Nanasawa
    1979 Volume 52 Issue 3 Pages 846-848
    Published: 1979
    Released: April 19, 2006
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    Three perfume acetals and four vitamin acetals have been synthesized by the acid-catalyzed reactions of vinylbenzyloxy- and methoxy-substituted benzaldehydes with citronellol and the reactions of vinylbenzaldehyde with vitamins B6, C, B1 and B2, respectively. The acid hydrolyses of these novel acetals readily released citronellol and vitamins under mild conditions, some accelerations of the hydrolysis rate by the electron-donating para substituents being observed in the case of the perfume acetals.
  • Kazunori Maruyama, Takashi Ito, Akio Yamamoto
    1979 Volume 52 Issue 3 Pages 849-855
    Published: 1979
    Released: April 19, 2006
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    Treatment of Mn(acac)3 (acac=acetylacetonato ligand) with AlPh3·Et2O in the presence of PCy3 (Cy=cyclo-C6H11) gave a new diphenylmanganese(II) complex, Ph2MnPCy3 (1). Complex 1 reacted with allylic compounds, CH2=CHCH2X (X=Br, OPh, OCH2CH=CH2, and OCOCH3), to give allylbenzene. Carbon dioxide was found to be inserted into the phenyl-manganese σ-bond of 1 to give bis(benzoato)manganese complex, (PhCOO)2MnPCy3, 2, which on successive treatment with HCl and diazomethane produced methyl benzoate. Complex 1 reacted with aldehydes, ketones, and esters having no active α-hydrogen atom to give alkoxomanganese species in solution, indicating that the insertion of C=O double bond into the phenyl-manganese σ-bond occurred. On the other hand, acetone and acetophenone reacted with Ph2MnPCy3 to give benzene and 2-oxoalkyl complexes, (RCOCH2)2Mn(PCy3)m (R=Me, Ph), 3. Reaction of alcohols with 1 afforded alkoxomanganese compounds which catalyze the Tishchenko type and Meerwein-Pondorf type reactions as well as transesterification reactions at room temperature.
  • Koichi Komatsu, Isao Tomioka, Kunio Okamoto
    1979 Volume 52 Issue 3 Pages 856-860
    Published: 1979
    Released: April 19, 2006
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    The reaction of trichlorocyclopropenium tetrachloroaluminate with cyclopropylbenzene has been found to readily afford the disubstitution products, bis(p-cyclopropylphenyl)- (1a), (p-cyclopropylphenyl) (o-cyclopropylphenyl)-, and bis(o-cyclopropylphenyl)cyclopropenones, each of which has been separated and fully characterized spectroscopically. The tris(p-cyclopropylphenyl)cyclopropenium ion (2) could not be obtained by the direct trisubstitution of the trichlorocyclopropenium ion with cyclopropylbenzene, but has been synthesized via two other routes starting from cyclopropenone 1a. The UV and 13C NMR spectral data of the cation 2 indicated the conjugative interaction of the para-cyclopropyl group with the cyclopropenium ring. However, the cation-stabilizing effect of the para-cyclopropyl group, as shown by the pKR+ value (3.23 in 23% ethanol) for 2, is much smaller than in the case of the tris(p-cyclopropylphenyl)methyl cation. This has been interpreted in terms of the decrease in delocalization of the positive charge to the para-position of the cation 2, when compared with the triarylmethyl analogue.
  • Sigeru Torii, Tsutomu Inokuchi, Kiyoto Kawai
    1979 Volume 52 Issue 3 Pages 861-866
    Published: 1979
    Released: April 19, 2006
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    A stereocontrollcd synthesis of dl-isopetasol (1a) from trans-5-oxodecalin-8a,2-carbolactone (2a) is described. The key intermediate, trans-5,5-ethylenedioxy-1β,8aβ-dimethyldecalin-2-one (7b) was prepared by reductive methylation of trans-5,5-ethylenedioxydecahydrocyclopropa[d]naphthalen-2-one (5) for introducing the vicinal two methyl groups at C-1 and C-8a carbon atoms. The cyclopropyl ketone 5 was obtained by reduction of the acetal of 2a followed by (1) tosylation of the primary alcohol, (2) oxidation of the secondary alcohol with Corey’s NCS–DMS reagent, and (3) cyclization with t-BuOK. Reduction of 5 with lithium in liquid ammonia provides initially the corresponding enolate anion, which can be trapped with methyl iodide to give trans-5,5-ethylenedioxy-1α,8aβ-dimethyldecalin-2-one (7a), smoothly. Epimerization of 7a with MeONa in MeOH gave the desired intermediate 7b. Reduction of 7b with lithium in liquid ammonia gives the 2α-alcohol 8b, stereoselectively. The conversion of 8b into 1a was carried out as follows: (1) deacetalization of 8b followed with acetylation, giving trans-6α-acetoxy-4aβ,5β-dimethyldecalin-1-one (9b); (2) reduction of 9b with NaBH4 and subsequent dehydration affording the olefinic acetate 11; (3) oxidation of 11 with CrO3–pyridine complex, giving the enone 12; (4) aldol condensation of 12 with acetone followed by dehydration, isomerization of double bond, and hydrolysis, providing the desired 1a.
  • Takashi Sugimoto, Keiko Shibata, Sadao Matsuura
    1979 Volume 52 Issue 3 Pages 867-870
    Published: 1979
    Released: April 19, 2006
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    Several imidazo[1,2-c]pteridines with a functional group such as amino, alkylamino, alkoxyl, or hydroxyl group at the 6-position were synthesized by a nucleophilic replacement of 6-methylthioimidazo[1,2-c]pteridine with an appropriate nucleophile. The key intermediate methylthio compound was synthesized by condensation of 4-amino-2-methylthiopteridine with chloroacetaldehyde. Similarly, 4-amino-6,7-dimethyl-2-methylthiopteridine and chloroacetaldehyde gave 2,3-dimethyl-6-methylthioimidazo[1,2-c]pteridine, which was also used as a precursor to synthesize several imidazopteridines analogous to above.
  • Toshio Sugita, Junichi Nakagawa, Kazuhito Nishimoto, Yasuhiro Kasai, K ...
    1979 Volume 52 Issue 3 Pages 871-879
    Published: 1979
    Released: April 19, 2006
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    The erythro and threo isomers of 1-bromo-2-methoxy-1,2-diphenylethane (1), 1-bromo-2-acetoxy-1,2-diphenylethane (2), 1-bromo-2-methylsulfonyloxy-1,2-diphenylethane (3), 1-bromo-2-methylthio-1,2-diphenylethane (4), stilbene dibromide (6), and stilbene dichloride have been prepared. These compounds were allowed to react with butyllithium in various solvents to give cis- and trans-stilbenes. Depending on the solvent, the stereochemistry of the elimination of 1 changed from a complete syn-type (in nonpolar solvents) to a less-selective type. The same tendency was observed in the cases of 2 and 3. In contrast, anti-elimination was favored for 4 and 6, and a different type of solvent effect was observed. Elimination reactions with lithium metal and pentylmagnesium bromide were also carried out. Possible mechanisms for eliminations are discussed.
  • Yasuo Kikuchi, Takashi Koda
    1979 Volume 52 Issue 3 Pages 880-883
    Published: 1979
    Released: April 19, 2006
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    Sodium carboxymethylcellulose(anti-thrombogenic material)(CMC) reacted with [2-(diethylamino)ethyl]dextran hydrochloride(anti-cancer material)(EA) having an opposite charge and three groups of different basicity at different hydrogen ion concentrations to form novel water-insoluble precipitates, the so-called polyelectrolyte complex(PEC) comprised of both biomedical materials, focusing on the coagulation of precipitate(PEC) produced. The mole ratio N(EA)/Na(CMC) of the reaction mixture in solution at the start coagulation increased with a lowering of hydrogen ion concentration. This depended on the change of the degree of dissociation of EA and CMC with changing hydrogen ion concentration. The nitrogen contents which describe the mole ratios of EA/CMC in each PEC thus prepared were determined to range from 1.75 to 4.51. It was established that the hydrogen ion concentration and mixing mole ratio of N/Na in solution play an important role in determining the composition ratio of EA/CMC in the PEC. The results of IR, elemental analyses, solubility measurements, degree of swelling in water, color reaction with Toluidine Blue, and blood clotting test for PEC, revealed that the molecular structure of the various PEC’s differed according to the hydrogen ion concentration and the mole ratio of reaction mixture in solution, though all PEC’s were prepared from the same starting materials. It appears that the degree of dissociation and conformation of EA and CMC change with hydrogen ion concentration. The blood clotting tests were performed on a slightly swelled tablet of PEC where it was found that the PEC suppressed coagulation of the blood.
  • Yoshiro Ogata, Katsuhiko Takagi, Yasuharu Sasoh
    1979 Volume 52 Issue 3 Pages 884-887
    Published: 1979
    Released: April 19, 2006
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    Photo-induced dechlorination of β-benzene hexachloride(β-BHC) in alkaline alcohols has been studied. Benzene is a major product accompanying other minor products such as chlorobenzene, alkoxybenzene, and benzyl alcohols. Their yields vary a great deal depending on the kind of alcohol. The efficiency of reaction and the selectivity of benzene increase in the order : methanol<ethanol<2-propanol. The reaction may go by way of dechlorination of β-BHC with base in the dark giving trichlorobenzenes(predominantly 1,2,4-isomer) followed by its photochemical dechlorination. The radical chain mechanism involving H-abstraction by Cl· atom is presented, since the efficiency is raised ca. 8 times as much as that in the dark.
  • Yoshiya Kera
    1979 Volume 52 Issue 3 Pages 888-894
    Published: 1979
    Released: April 19, 2006
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    It was confirmed that the kinetics of CO-oxidation over powdered V2O5 under the condition of (PCOPO2) more than 2 differed clearly from that under the (PCOPO2) less than 2 at 450 °C. The activation energies were 5.6 kcal/mol at 250–410 °C and 13 kcal/mol at 410–490 °C under a reductive condition of (PCOPO2)=4.4, and on the other hand 5.9 kcal/mol at 250–490 °C under an oxidative condition of (PCOPO2)=0.43. On a thin crystalline sample, in which the (010) plane was exposed extensively to the surface, a very rapid process appeared at the initial stage but was soon followed by a steady process. The rapid process was explained well by the Elovich law. On the thin crystalline, cautiously purified, the Elovich process did not appear, but the initial rapid process was kept steadily for 10–20 min and then followed by the other steady process. Accompanied by the change in the kinetics during the reaction, the activation energy changed from 2.3 kcal/mol at 271–410 °C and 17 kcal/mol at 410–480 °C to 29 kcal/mol at 271–480 °C under the (PCOPO2)=2.1. Based on these results, the effects of the crystalline planes and the purities on the working states of V2O5 crystal in CO-oxidation are discussed.
  • Yoko Kanazawa, Hirotake Kamei
    1979 Volume 52 Issue 3 Pages 895-901
    Published: 1979
    Released: April 19, 2006
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    The hexagonal phases of sodium octadecanoate–water system NaS and sodium hexadecanoate–sodium tetradecanoate–water system Na(P+M) were studied by sodium-23 NMR and spin label ESR in the temperature range 40–100 °C, covering the transition temperature of isotropic-liquid crystal TI-L and that of liquid crystal-gel TL-G. The ESR spectrum of liquid crystal systems aligned by the magnetic field and the center line of 23Na NMR spectrum were analyzed. The motions of the alkyl chain and sodium ion are reflected on the ESR and NMR spectral shape and width. The NMR line width is predominantly determined by the local motion of the cation attached on the hydrocarbon rod. During the phase separation region its correlation time τc\simeq10−10 s is constant, comparable to that of chain motion. The change in the local motions of these two species is similar, being continuous across TI-L but drastic across TL-G.
  • Hidetoshi Karasawa, Tai Sasamoto, Rei Yugeta, Shin Sato
    1979 Volume 52 Issue 3 Pages 902-907
    Published: 1979
    Released: April 19, 2006
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    The relative rate constants of reactions of oxygen atoms with several olefins and 2-methylpropane have been determined in liquid carbon dioxide at −18 °C, using the γ-radiolysis of carbon dioxide in the presence of these hydrocarbons. They are : 1-butene, 1.0; cis-2-butene, 2.3; trans-2-butene, 3.0; 2-methylpropene, 2.9; 2,3-dimethyl-2-butene, 2.0; 2-methylpropane, 0.07. These relative values are very different from those obtained in the gas phase. A possible reason is discussed and a simple theoretical treatment is proposed for the competition between diffusion and reaction on the basis of the idea of a “collision set” in the liquid phase. The reaction of oxygen atoms with paraffin in liquid carbon dioxide seems to be faster than that in the gas phase. The reason is not clear at present.
  • Setsuko Kudo, Akio Iwase
    1979 Volume 52 Issue 3 Pages 908-910
    Published: 1979
    Released: April 19, 2006
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    The reaction mechanism of the electrogenerated hyperoxide ion with bis(acetylacetonato)cobalt(II) in dimethyl sulfoxide and acetone has been investigated. The reaction was conducted in a 0.05 mol dm−3 TBAP solution at 20 °C in an open system. Co(acac)2 reacted with the hyperoxide ion which was generated by the controlled potential electrolysis of dissolved oxygen to afford the following product, [(acac)2 Co–O2–Co(acac)2]2−. The complex was separated in solution by column chromatography using alumina as the adsorbent. The electronic spectrum and oxidation state are discussed.
  • Sukeo Onodera
    1979 Volume 52 Issue 3 Pages 911-913
    Published: 1979
    Released: April 19, 2006
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    The gas-chromatographic study of the thermal decompositions of the complexes, [Co(NO2)(NH3)5]Cl2 (I), cis- (II) and trans-[Co(NO2)2(NH3)4]Cl (III), [Co(NO2)3(NH3)3] (IV), K[Co(NO2)4(NH3)2] (V), and K2[Co(NO2)5NH3] (VI) are reported. The EGA curves for these complexes show that the compounds decompose in two or three stages. In the first stage (ca. 140–240 °C), all complexes evolve nitrogen with the evolution of ammonia and/or nitrogen monoxide. The second stage (ca. 210–300 °C) has been ascribed to the evolution of ammonia from the intermediate dissociation products of compound I, II, and III. The third stage (ca. 275–350 °C) has been ascribed to the evolution of nitrogen monoxide from the solid residue with the exception of IV.
  • Yasuji Nakayama, Shun’ichiro Ooi, Hisao Kuroya
    1979 Volume 52 Issue 3 Pages 914-917
    Published: 1979
    Released: April 19, 2006
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    The bis((S,S)-2,4-pentanediamine)platinum(II) chloride monohydrate crystallizes in the space group P212121 with four formula units in a unit cell of dimensions a=12.089(3), b=13.547(3), c=10.697(2) Å. The crystal structure has been determined from diffractometer data and refined to R=0.052 for 1903 independent reflections. The Pt atom has a square planar coordination by four N atoms, the average value of the Pt-N distance being 2.05 Å. The complex has a pseudo two-fold axis which is perpendicular to the coordination plane defined by the four N atoms. The 6-membered chelate ring is of a chair conformation and one methyl group is axial with respect to the chelate ring, while the other is equatorial. From a comparison of the circular dichroism spectra of the diammine-(S,S)-2,4-pentanediamineplatinum(II) and the bis((S,S)-2,4-pentanediamine)platinum(II) ions, the effect of the (S,S)-2,4-pentanediamine on the rotatory strength of the Pt(II) complex has been found to be not additive.
  • Yoshinori Sugitani, Kenji Kato, Kozo Nagashima
    1979 Volume 52 Issue 3 Pages 918-921
    Published: 1979
    Released: April 19, 2006
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    A series of uranium–mica type compounds M(UO2)2(XO4)2·nH2O, where M=Ca, Sr, Ba, Mg, Na2, K2, and (H3O)2; X=P and As, as well as the doped samples of Mg(UO2)2(PO4)2·nH2O : Mn(0.03 mol %) and Zn-(UO2)2(PO4)2·nH2O: Cu(0.1 mol %), have been prepared and measured for emission spectra under the UV(365 nm) excitation and decay times. Some of these samples, e.g., (H3O)2(UO2)2(AsO4)2·nH2O, have been found to give weak shoulders and a separated band, in addition to the six bands so far reported for other uranyl(VI) compounds. Samples containing AsO43− ions in place of PO43− gave emission spectra, where the main bands shifted by approximately 100 cm−1 to lower energy also giving shorter life times. The decay times of the six emission bands of Mg(UO2)2(PO4)2·nH2O have been found to have the same value of 2.5×10−4 s.
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