Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 54 , Issue 9
Showing 1-50 articles out of 72 articles from the selected issue
  • Tadao Kenjo
    1981 Volume 54 Issue 9 Pages 2553-2556
    Published: 1981
    Released: June 02, 2006
    JOURNALS FREE ACCESS
    Polytetrafluoroethylene (PTFE)-bonded Raney nickel hydrogen electrodes have been prepared and their polarizations have been measured at 62 °C, using 6 M KOH (1 M=1 mol dm−3) as an electrolyte. The electrodes were reproducible in polarization characteristics from electrode to electrode. The polarization resistance was found to be 0.29 Ω cm−2 for the electrode loaded with a 48-mg cm−2 catalyst. The limiting current density was 600 mA cm−2 for the electrode loaded with a 45.4-mg cm−2 catalyst. The influences of the pressure of the press machine and of the PTFE content on the polarizations have been investigated. The polarization resistance decreases with the catalyst loading in the manner to be expected from the reaction mechanism of the gas diffusion through electrolyte film. An experimental evidence for this reaction mechanism has been obtained by measuring the polarization of an electrode of a triple-layered structure containing a silver powder layer.
  • Tamotsu Inabe, Yoshio Matsunaga, Mikiko Nanba
    1981 Volume 54 Issue 9 Pages 2557-2564
    Published: 1981
    Released: June 02, 2006
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    In addition to the six crystalline pyrene complexes reported earlier, the high-temperature forms of the following nineteen 1:1 molecular complexes have been found to be isomorphous to each other; the pyrene complexes with 1,3,5-trinitrobenzene, 2,4,6-trinitrophenol, 4-nitrophthalic anhydride, pyromellitic dianhydride, 5-nitrobenzofuroxan, 4,6-dinitrobenzofuroxan, and benzotrifuroxan, the fluoranthene complexes with 2,4-dinitrophenol, 1,3,5-trinitrobenzene, 2,4,6-trinitrochlorobenzene, 2,4,6-trinitrophenol, 2,4,6-trinitrotoluene, 4-nitrophthalic anhydride, pyromellitic dianhydride, 4,6-dinitrobenzofuroxan, and benzotrifuroxan, and the phenanthrene complexes with 1,3,5-trinitrobenzene, 2,4,6-trinitrophenol, and 4,6-dinitrobenzofuroxan. Furthermore, metastable isomorphous forms were obtained in the process of the solidification of the melt of the following three complexes: fluoranthene-5-nitrobenzofuroxan, phenanthrene-2,4,6-trinitrotoluene, and phenanthrene-4-nitrophthalic anhydride. Rather large entropies of the transitions to these unique high-temperature forms, up to 57 J mol−1 K−1, are often comparable with the entropies of melting, 46–67 J mol−1 Kr−1. The isomorphism in these twenty-eight complexes is demonstrated by essentially identical and very simple X-ray diffraction patterns and/or by the formation of continuous solid solutions between pairs of these forms. A trigonal lattice is proposed as the probable structure of these high-temperature forms. A broad-line 1H NMR study clearly showed that the unusual features of these isomorphous forms are mostly associated with the onset of a large degree of molecular motion at the transition temperatures.
  • Ikuo Tokue, Masami Ikarashi
    1981 Volume 54 Issue 9 Pages 2565-2568
    Published: 1981
    Released: June 02, 2006
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    Benzene, pyridine, and pyrazine were excited by electron impact (0–70 eV) under low pressure conditions. In the wavelength region of 250–510 nm, emissions from H, CH, C2, and CN (except for benzene) fragments were observed. Formations of H(n=4) and CH(A2Δ) from benzene, pyridine, and pyrazine were investigated. The appearance potentials for the hydrogen Balmer β emission were determined to be 19.5±1.0 eV in benzene, 19.7±1.0 eV in pyridine, and 19.6±1.0 eV in pyrazine. The appearance potentials for the CH(A-X) emission were also determined to be 12.7±1.0 and 21.4±1.0 eV in benzene, 20.1±1.0 eV in pyridine, and 18.5±1.0 eV in pyrazine. No emissions from the excited parent species of pyridine and pyrazine were observed.
  • Yasuhiro Uosaki, Masaru Nakahara, Jiro Osugi
    1981 Volume 54 Issue 9 Pages 2569-2572
    Published: 1981
    Released: June 02, 2006
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    EDA-complex formation and 1,4-cycloaddition of tetracyanoethylene (TCNE) with styrene,α-methylstyrene, 1,1 -diphenylethylene, cis-stilbene, and trans-stilbene were studied spectrophotometrically in chloroform at 25 °C. Formation constants of the EDA complexes were found to be in the order, trans-stilbene>styrene>α-methylstyrene>cis-stilbene>1,1-diphenylethylene. The difference in the formation constants was discussed in terms of both electronic and steric effects of the donors studied. α-Methylstyrene and 1,1-diphenylethylene underwent thermal cycloaddition to TCNE faster than styrene. It is suggested that some charge separation took place in the transition state. The fact that trans- and cis-stilbenes do not react with TCNE was explained in terms of the difference in stability of the 1,4-cycloadducts estimated from the 1,4-bislocalization energy obtained by Dewar’s perturbation molecular orbital method.
  • Nobuyuki Ito, Tadashi Kato, Tsunetake Fujiyama
    1981 Volume 54 Issue 9 Pages 2573-2578
    Published: 1981
    Released: June 02, 2006
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    The concentration dependences of the mutual diffusion coefficients at 24, 37, and 63 °C were observed for a binary solution of t-butyl alcohol (TBA) and water by the use of the light scattering method. The observed concentration dependences of the mutual diffusion coefficients were explained well by postulating the existence of a “moving unit”–a group of molecules which move together for a time much longer than the velocity correlation time. The structure of the moving units which are formed in the solution are (H2O)11TBA at 24 °C and (H2O)20TBA at 63 °C in the concentration range of 0<xTBA<0.1, where xTBA is the mole fraction of TBA. Taking into account the local structures, which had been determined from the concentration dependences of the mean-square concentration fluctuation values, we could conclude that water molecules form a polyhedron which encages a TBA molecule and that these cages then gather together to form an aggregate. It is essential that these polyhedra do not share their faces with each other in the aggregate. It was also concluded that the number of cages which form an aggregate increases with an increase in the temperature. This suggests the existence of a pseudo-critical temperature for this system. That is to say, the TBA–water solution can separate into two phases under high pressures, a TBA-rich phase and a water-rich phase, in the latter of which almost all the molecules form polyhedra.
  • Byong-Tae Chang
    1981 Volume 54 Issue 9 Pages 2579-2582
    Published: 1981
    Released: June 02, 2006
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    Thermodynamic properties of boehmite in alkaline pH range are determined by applying the extended Debye-Hückel theory to its solubility data in NaOH solutions. When log(Ks/aw2), where Ks=mHmA1 and aw is the activity of the water in NaOH solutions, is plotted against a Debye-Hückel function of ionic strength (I), I1⁄2⁄(1+Bta1I1⁄2), at a given temperature, the curve approaches gradually the theoretical Debye-Hückel limiting slope (2At) with decrease in the ionic strength, and at high ionic strength it deviates positively from the straight line. Under the assumption of the same ionic size parameters for OH and Al(OH)4 ions, the ionic solubility product, Ks°=aHaA1aw2, for boehmite is given by following equations in the temperature range from 80 to 250 °C: log Ks°=−2663⁄T−5.71 (Case 1) or log Ks°=−2764⁄T−5.45 (Case 2). From a comparison of the temperature dependences of Ks° for boehmite and gibbsite, a transition temperature between the two alumina hydrates was calculated to be 60±3 °C.
  • Tooru Hasebe, Gen Soda, Hideaki Chihara
    1981 Volume 54 Issue 9 Pages 2583-2586
    Published: 1981
    Released: June 02, 2006
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    Proton spin-lattice relaxation time T1 of 2,2-dimethylpropanoic acid in its plastic phase was measured at 10 MHz up to 120 MPa between 268 K and 330 K. A minimum in T1 appears in the low-pressure region which is due to overall reorientation of molecules. The T1 minimum value decreases as the pressure increases in a way different from simple-minded prediction. The activation volume, 25±3 cm3 mol−1, is twice as large as in other plastic crystals when normalized by the molar volume. The pressure dependence of the activation enthalpy is also about twice as large. These can be rationalized by considering associated dimers as the reorienting unit. The phase diagram is given and the volume changes associated with the transition and with the fusion were derived (15.6 and 5.86 cm3/mol of dimer).
  • Akiko Ikekawa, Sohachiro Hayakawa
    1981 Volume 54 Issue 9 Pages 2587-2591
    Published: 1981
    Released: June 02, 2006
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    Influence of ball-milling on the X-ray diffraction pattern, the thermal properties, the IR spectra, the particle size distribution and the solubility of amobarbital was investigated. The fraction of crystal I decreased, and the fraction of crystal III and the amorphous part increased at the first stage of ball-milling. The heat of fusion decreased slightly by ball-milling, which was considered to be due to the increase in the fraction of the amorphous part. The melting point lowered by 1–3 °C and the NH and CO absorptions in the IR spectra were influenced by ball-milling, which was considered to be due to the transformation of crystal I into crystal III. The particle size decreased at the first stage of ball-milling. It was considered that the transformation of crystal I into crystal III was remarkable when the particles were broken. The solubility of amobarbital in the KH2PO4–Na2HPO4 buffer solution with pH of 6.0 increased by ball-milling, which was considered to be due to the increase in the fraction of the amorphous part and crystal III.
  • Tsuyoshi Harada, Nagamune Nishikido, Yoshikiyo Moroi, Ryohei Matuura
    1981 Volume 54 Issue 9 Pages 2592-2597
    Published: 1981
    Released: June 02, 2006
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    The rates of trinitromethanide anion formation by the reaction of tetranitormethane with hydroxide ion were measured in the presence of anionic, cationic and nonionic surfactant micelles in aqueous solutions. Using the analytical approach which takes into consideration the distribution of hydrophobic reactants among micelles, k1 (a second-order rate constant on micelles associated with one reactant molecule) and K1/N(K1: an association constant of the reactant with micelles having no reactant, N: an aggregation number of surfactant molecule in a micelle) were estimated. The anionic surfactant exhibited no effect on the reaction rate. In the case of cationic surfactants, both k1 and K1 values increased not only with alkyl chain length but also with hydrophobicity of the surfactants. In the case of nonionic surfactants, an increase of alkyl chain length with a given oxyethylene unit resulted in an increase in the k1 values, while an increase of oxyethylene group with the fixed alkyl chain length resulted in an appearance of the maximum k1 value. From temperature dependence of the reaction rate, a stabilization of the activated complex could be explained by an electrostatic interaction of the complex with the charged micellar surface. It was also found from the analytical approach that the distribution of tetranitromethane among micelles used in the present experiment could be approximated by the Poisson distribution.
  • Naoki Sugimoto, Muneo Sasaki, Jiro Osugi
    1981 Volume 54 Issue 9 Pages 2598-2602
    Published: 1981
    Released: June 02, 2006
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    Influence of pressure on the rate constants of the proton-transfer reactions between title compounds was studied in acetonitrile and dichloromethane at 25 °C up to 1000 bar by means of a high-pressure stopped-flow method. In the reaction of 2,4,6-trinitrotoluene (TNT) with N,N,N′,N′-tetramethylguanidine, the volume of activation for the forward reaction ΔVf\ eweq is −12.7±1.0 cm3 mol−1 in acetonitrile and −19.0±1.5 cm3 mol−1 in dichloromethane. In the reaction of TNT with 1,8-diazabicyclo[5.4.0]undec-7-ene, ΔVf\ eweq is −9.0±1.0 cm3 mol−1 in acetonitrile and −10.8±1.0 cm3 mol−1 in dichloromethane. These results are discussed in comparison with other proton-transfer reactions.
  • Kunio Fukushima, Hiromichi Takahashi
    1981 Volume 54 Issue 9 Pages 2603-2606
    Published: 1981
    Released: June 02, 2006
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    Raman spectra of N-methylpiperazine in proton donors and acceptors were measured. Forms of stable conformers in the donors and the acceptors were studied by comparison of the Raman spectra and normal vibration calculations. A conformational change of the molecule in the donors was found, suggesting the change of valence state of nitrogen atom, which is caused by hydrogen bonding.
  • Hitoshi Kanno, Ichimin Shirotani, Shigeru Minomura
    1981 Volume 54 Issue 9 Pages 2607-2609
    Published: 1981
    Released: June 02, 2006
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    The glass transition temperature (Tg) is measured as a function of pressure up to 200 MPa for the aqueous Li, Na, K, Rb, and Cs acetate solutions. The effects of cation radius on the glass transition of these solutions are discussed and some attempts are made to correlate Tg (and associated properties) with r (cation radius).
  • Mizuka Sano, Naoki Sato, Hiroo Inokuchi, Shohei Tamura
    1981 Volume 54 Issue 9 Pages 2610-2612
    Published: 1981
    Released: June 02, 2006
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    A bundle of carbon filaments, each about 20 cm in length and 7 μm in diameter, could be grown from purified graphitic material in argon plasma generated in a d.c. arc. The filaments were converted into softer filaments on heat-treatment to 3000–3400 °C. The filaments formed intercalation compounds of potassium, rubidium, and caesium. The electrical resistivities were found to be 1300, 610–660, 23–25, and 28–30 μΩ cm at 300 K for the original filament, the heat-treated filament, and the first stage golden and the second stage dark-blue intercalation compounds of the heat-treated filament, respectively.
  • Tohru Inoue, Masaru Ikeuchi, Takemi Kuroda, Ryosuke Shimozawa
    1981 Volume 54 Issue 9 Pages 2613-2619
    Published: 1981
    Released: June 02, 2006
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    A pressure-jump technique and a spin label technique were applied to the kinetic investigation of the association-dissociation reactions between monomer and micelle in surfactant solutions of STS, TMTS, TETS, and TPTS. The rate constants for the reactions were determined at several temperatures by the pressure-jump experiment. The ESR spectra of a spin probe, 5-SAL, solubilized in the micelles were analyzed in terms of the rotational correlation time, τc. A linear relationship was found between kd, the dissociation rate constant, and τc−1. This indicates that the dissociation rate depends on the fluidity of the micellar interior, and is in accord with the picture drawn by Aniansson et al. for the dissociation process. A qualitative discussion is presented on the activation parameters estimated from the present results according to the scheme presented by Aniansson et al.
  • Akinori Hasegawa, Akihiro Nagayama, Michiro Hayashi
    1981 Volume 54 Issue 9 Pages 2620-2623
    Published: 1981
    Released: June 02, 2006
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    The radical anions of ethyl- and vinyl- halosilanes formed in solid matrices of tetramethylsilane and their ESR spectra were investigated to be compared with results obtained from related radical anions. These radical anions have a trigonal bipyramidal structure with two axial and two equatorial positions. Ethyl and methyl groups which are less electronetative than H prefer the equatorial positons. The vinyl group with a single π electron system occupies the equatorial position due to its electron-donating capability, in spite of its larger electronegativity.
  • Noriaki Hirayama, Kunikatsu Shirahata, Yuji Ohashi, Yoshio Sasada
    1981 Volume 54 Issue 9 Pages 2624-2628
    Published: 1981
    Released: June 02, 2006
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    The molecular and crystal structure of fortamine sulfate trihydrate, C8H18N2O4·H2SO4·3H2O, was determined by X-ray analysis. The space group is P21 with a=7.2516(9), b=11.193(1), c=9.022(1) Å, β=90.55(2)°, and Z=2. The structure was solved by direct methods, and least-squares refinement using 1679 reflexions led to the final R value of 0.063. The ring conformation of fortamine sulfate is a chair form which corresponds to a chair obtained by inversion of that in the dihydrochloride. This is an extraordinary example of the cyclohexane ring inversion caused by the anion exchange in the crystal. The ring conformation of fortamines in solution and in crystal are compared and discussed.
  • Isoshi Nukatsuka, Mitsuhiko Taga, Hitoshi Yoshida
    1981 Volume 54 Issue 9 Pages 2629-2632
    Published: 1981
    Released: June 02, 2006
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    The capillary-tube isotachophoresis technique was used to determine sodium(I), magnesium(II), calcium(II), strontium(II), and barium(II). The complex-forming equilibria between CyDTA and the metal ions were used to expand the differences among their effective mobilities. The mobilities of IIa metal ions decreased with increases in the pH of the leading electrolytes and in the CyDTA concentration in the leading electrolytes. The simultaneous determination of the above five cations could be performed when the pH of the leading electrolyte was adjusted at 5.5 or above. The relative standard deviations were 1.7–2.2% for determining 15.0–25.0 nmol of the cations when the pH of the leading electrolyte was 5.70. Magnesium(II) and calcium(II) ions underwent “enforced isotachophoretic” migration.
  • Yoshiaki Onoue, Keiz\={o} Hiraki, Yasuharu Nishikawa
    1981 Volume 54 Issue 9 Pages 2633-2635
    Published: 1981
    Released: June 02, 2006
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    The spectral characteristics and its application to measurement of porphyrins were investigated by use of room temperature phosphorometry. Certain porphyrin compounds adsorbed on filter paper exhibit intense E-type delayed fluorescence. This could be utilized for the determination of porphyrin derivatives.
  • Mitsuru Sano, Hirohiko Adachi, Hideo Yamatera
    1981 Volume 54 Issue 9 Pages 2636-2641
    Published: 1981
    Released: June 02, 2006
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    The core binding energies of N1s and S2s in cis-1,2-dicyano-1,2-ethanedithiolate (maleonitriledithiolate, mnt) complexes were measured by means of X-ray photoelectron spectroscopy (XPS), and the energy differences between N1s and S2s, ΔE, were found to be 171.7–172.6 eV throughout the complexes studied. The lowest ΔE value, 171.7 eV, was shown by [Ni(mnt)2]. The electronic structures of [Ni(mnt)2] and [Ni(mnt)2]2− were calculated by the discrete variational Xα method. The XPS measurements and the molecular orbital (MO) calculations provide consistent results that the oxidation state of the nickel atom is +2 for both nickel mnt complexes and that the highest occupied MO is 5b3g, which is mainly localized on ligands and which holds an unpaired electron in [Ni(mnt)2].
  • Keiichi Tsukahara, Yasuo Yamamoto
    1981 Volume 54 Issue 9 Pages 2642-2645
    Published: 1981
    Released: June 02, 2006
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    The kinetics of the reactions of [Co(phen)3]3+, [Co(bpy)3]3+, and [Co(en)(phen)2]3+ (phen=1,10-phenanthroline, bpy=2,2′-bipyridine, and en=ethylenediamine) with ascorbic acid (H2A) have been studied over the temperature range from 17.0 to 35.0 °C, at an ionic strength of 0.10 mol dm−3 (LiClO4), and over the pH range from 3.60 to 5.04 (acetate buffer). The [Co(phen)3]3+ and [Co(bpy)3]3+ ions were reduced by both HA (k1 path) and A2− (k2 path) ions: the second-order rate constants at 25.0 °C are (0.40±0.07) dm3 mol−1 s−1 and (5.8±1.1)×106 dm3 mol−1s−1 for the [Co(phen)3]3+ ion, and (0.13±0.02) dm3 mol−1 s−1 and (2.1±0.5) ×106 dm3 mol−1 s−1 for the [Co(bpy)3]3+ ion. The [Co(en)(phen)2]3+ ion was reduced only by the A2− ion; k2=(1.0±0.2) ×106 dm3 mol−1 s−1 (25.0 °C). The [Co(phen)3]3+, [Co(bpy)3]3+, and [Co(en)(phen)2]3+ ions were not reduced by H2A. The activation parameters (ΔH\ eweq and ΔS\ eweq) for the ascorbate reduction of the [Co(phen)3]3+ ion were larger than those of the [Co(bpy)3]3+ ion. This is in contrast to the results of the self-exchange reactions of the [Co(phen)3]3+⁄2+ and [Co(bpy)3]3+⁄2+ couples. The mechanisms will be discussed in terms of the activation parameters and the Marcus cross relationships.
  • Takayuki Matsushita, Hiroshi Kono, Toshiyuki Shono
    1981 Volume 54 Issue 9 Pages 2646-2651
    Published: 1981
    Released: June 02, 2006
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    Some chloromanganese(III) Schiff base complexes react with hydrogen chloride to give deep green complexes with the empirical formula of MnLCl2 or MnL′2Cl2, where H2L denotes quadridentate ligands such as N,N′-disalicylideneethylenediamine and its analogs, and where HL′ denotes bidentate ligands such as N-butylsalicylideneamine and its analogs. These complexes are nonelectrolytes in acetonitrile. Their magnetic moments at room temperature fall within the range of 3.9 to 4.1 BM, and the magnetic susceptibilities obey the Curie-Weiss law with small θ values over the temperature range of 77 to 300 K, indicating that the oxidation state of the manganese ions in these complexes is +IV. The electronic spectra show an intense band around 16000 cm−1 which can be assigned to a charge-transfer transition. In the cyclic voltammograms, two cathodic waves are observed at half-peak potentials around +0.9 V and −0.2 V(vs. SCE); they can be assigned to the reductions of Mn(IV) to Mn(III) and of Mn(III) to Mn(II) respectively. The probable configurations of the complexes are discussed on the basis of the infrared spectra.
  • Yuichi Shoji, Ryoko Matsuzaki, Yuzo Saeki
    1981 Volume 54 Issue 9 Pages 2652-2655
    Published: 1981
    Released: June 02, 2006
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    The reaction between gaseous AlCl3 and steam, and the products formed were examined by X-ray analysis, TG, DTA, and electron microscopy. The thermal transitions of the Al2O3 formed under various conditions were also examined. The reaction between gaseous AlCl3 and steam occurs even at 150 °C and proceeds rapidly above about 400 °C. The product is amorphous Al2O3 below 600 °C, amorphous Al2O3 containing poorly crystallized γ-Al2O3 at 800 °C, γ-Al2O3 containing amorphous Al2O3 at 900 °C, and γ-Al2O3 at 1000 °C. Also, it was observed that the Al2O3 formed below 900 °C included a chloride oxide of aluminium, which decomposed in the vicinity of 830 °C to form γ-Al2O3 with the evolution of gaseous AlCl3. On heating the amorphous Al2O3 formed by the reaction between gaseous AlCl3 and steam, the transition: amorphous \xrightarrowca.700°C χ \xrightarrowca.800°C κ \xrightarrowca.1000°C α occurs; and on heating the γ-Al2O3 formed by the same reaction, the transition: γ \xrightarrowca.900°C δ \xrightarrowca.1000°C θ \xrightarrowca.700°C α occurs.
  • Taichi Sato, Takato Nakamura, Teruo Fujimatsu
    1981 Volume 54 Issue 9 Pages 2656-2661
    Published: 1981
    Released: June 02, 2006
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    The extraction of bivalent manganese, cobalt, copper, zinc and cadmium from hydrochloric acid solutions by tricaprylmethylammonium chloride (Aliquat-336) has been examined usmg various diluents such as benzene, chlorobenzene, o-dichlorobenzene, toluene, o-xylene, m-xylene, nitrobenzene, carbon tetrachloride, chloroform, and 1,2-dichloroethane. It was found that by assuming a regular solution, the distribution coefficient and the enthalpy change associated with metal extraction can be expressed in terms of the solubility parameters of Aliquat-336, diluent and the complex formed in the organic phase and their molar volumes. An empirical relation holds between distribution coefficient and the viscosity of diluent.
  • Yonezo Maeda, Yoshihiro Katsuki, Tooru Morinaga, Yoshimasa Takashima
    1981 Volume 54 Issue 9 Pages 2662-2667
    Published: 1981
    Released: June 02, 2006
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    Various iron compounds have been irradiated with gamma-rays of cobalt-60. The foreign-charge states of the irradiated compounds were confirmed by means of Mössbauer spectroscopy. The results showed that high-spin iron(III) compounds with large conjugated molecules and low-spin iron(II) compounds are insensitive to γ-radiations. However, iron(III) compounds with carboxyl groups or reducing ligands and low-spin iron(III) compounds are sensitive to γ-radiations. Further, FeCl2·4H2O was found to be insensitive to radiation up to a total exposure dose of 109 R, in contrast to other ionic iron(II) compounds.
  • Goro Hihara, Hiroshi Miyamae, Miharu Nagata
    1981 Volume 54 Issue 9 Pages 2668-2671
    Published: 1981
    Released: June 02, 2006
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    A simple spectrophotometric method has been developed for the determination of ethylenediamine in an aqueous or ethanolic solution. This method is based on the reaction of ethylenediamine with phthalaldehyde and 2-mercaptoethanol, and on the measurement of the absorbance of the yellow-developed solution at 430 nm. Beer’s law holds for 0.5–10 μg of ethylenediamine per 1 ml. Secondary and tertiary amines do not interfere with theestimation. Two of the primary amines, diethylenetriamine and triethylenetetramine, interfere with the estimation when present in quantities of more than 10 μg per ml of the sample solutions. 1,3-Propanediamine interferes seriously. The colored compound was found to be composed of ethylenediamine, phthalaldehyde, and 2-mercaptoethanol in a molar ratio of 1:2:1.
  • Tsunesuke Kajimoto, Yukishige Kitano, Hidetaka Takahashi, Jiro Tsuji
    1981 Volume 54 Issue 9 Pages 2672-2674
    Published: 1981
    Released: June 02, 2006
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    Bis(cyclohexyl isocyanide)palladium(II) chloride, PdCl2(C6H11NC)2 (1) was prepared from PdCl2. The configuration of the complex 1 is cis with respect to the isocyanides. The isocyano group in one cyclohexyl isocyanide takes axial conformation to chair form cyclohexyl group, while another takes equatorial conformation. By recrystallization of 1 from benzene bis(cyclohexyl isocyanide)palladium(II) chloride-benzene, PdCl2(C6H11NC)2(C6H6)2 (2) was prepared. IR spectrum of 2 shows a characteristic absorption at 700 cm−1 which is due to the benzene incorporated in the complex. Similar benzene complex was also prepared from PdBr2.
  • Kiichi Matsuhisa, Kunio Ohzeki, Tomihito Kambara
    1981 Volume 54 Issue 9 Pages 2675-2677
    Published: 1981
    Released: June 02, 2006
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    A highly sensitive and selective method has been developed for the determination of a trace amount of phosphate. It is based on the concentration of phosphate as the familiar molybdenum blue complex on the coagulated material prepared from finely divided anion and cation exchangers, collection of the mixed resin on a filter paper, and the subsequent measurement of the absorbance of the complex on the resulting thin layer of resin phase. The calibration curve shows a good proportionality in the concentration range of 1 to 6 μg P1−1. The absorbance corresponding to 1 μg P1−1 is 0.095. The method is successfully applied to the determination of phosphate in a tap water and a river water.
  • Tomoji S. Morita, Yoichi Sasaki, Kazuo Saito
    1981 Volume 54 Issue 9 Pages 2678-2682
    Published: 1981
    Released: June 02, 2006
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    A preparation method of pure crystalline salts, cis-[MoCl2(phen)2]X (phen, 1,10-phenanthroline; X=Cl, Br, CH3C6H4SO3) and cis-[MoCl2(bpy)2]Cl (bpy, 2,2′-bipyridine), has been established. They are stable in solid state under oxygen- and moisture-free conditions. They deteriorate within one hour in water at room temperature, but are much more stable in various organic solvents free from oxygen. In the visible region, two absorption peaks were observed in methanol at 21510 cm−1 (ε=2570 dm3 mol−1 cm−1) and 26740 cm−1 (ε=4420 dm3 mol−1 cm−1) for the phen complex, and one broad peak at 22820 cm−1 (ε=3630 dm3 mol−1 cm−1) for the bpy complex, which are assigned to the metal-to-ligand d-π* charge transfer transition.
  • Isamu Kinoshita, Kazuo Kashiwabara, Junnosuke Fujita, Keiji Matsumoto, ...
    1981 Volume 54 Issue 9 Pages 2683-2690
    Published: 1981
    Released: June 02, 2006
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    A series of complexes, [Co(en)n{NH2CH2CH2P(CH3)2}3−n]3+ (en=ethylenediamine, n=0,1,2) and three bis(ethylenediamine)cobalt(III) complexes of the related ligands, NH2CH2CH2P(C6H5)2, (S)-NH2CH(CH3)CH2P(C6H5)2, and rac-NH2CH2CH2P(C4H9)(C6H5) were prepared and resolved (or separated) into optical isomers, and their absorption and circular dichroism spectra were recorded. The molecular structure and the absolute configuration of (+)589-fac-[Co{NH2CH2CH2P(CH3)2}3]Br3·3H2O were determined by X-ray analysis. The crystals are lemon-yellow, orthorhombic, a=26.501(8), b=9.573(4), c=10.081(5) Å, space group P212121, z=4. The Co atom is surrounded by 3P and 3N in the facial manner with the average distances of 2.237 and 2.041 Å, respectively. The absolute configuration of the complex ion is Δ. The chelate rings are puckered and chiral to form a pseudo λ gauche conformation.
  • Masaaki Kojima, Junnosuke Fujita
    1981 Volume 54 Issue 9 Pages 2691-2694
    Published: 1981
    Released: June 02, 2006
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    The [Co{(R)-1-phenyl-1,2-ethanediamine}3]3+ complex yielded all of the four possible isomers, mer-Δ(lel3), mer-Λ(ob3), fac-Δ(lel3), and fac-Λ(ob3), while the [Co{(S)-3,3-dimethyl-1,2-butanediamine}3]3+ complex gave only two isomers of merΛ-(lel3) and fac-Λ(lel3). Two isomers, Λ(lel3) and Δ(ob3) of the [Co{(S,S)-2,3-butane-diamine}3]3+ complex were obtained. The formation ratios of these tris(1,2-diamine)cobalt(III) complexes were compared with those of the analogous complexes and discussed. The tetraammine complexes of all those diamines were also prepared. Absorption and circular dichroism spectra of all the complexes were recorded.
  • Shigenobu Funahashi, Keiji Saito, Motoharu Tanaka
    1981 Volume 54 Issue 9 Pages 2695-2699
    Published: 1981
    Released: June 02, 2006
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    The kinetics of reactions of meso-tetra(4-pyridyl)porphine (H2TPyP) with cobalt(II) acetate and cobalt(II) nitrate was studied in acetic acid spectrophotometrically. The rate of cobalt incorporation into H2TPyP is first-order in H2TPyP. The conditional first-order rate constants are expressed as follows: for the cobalt(II) acetate system k0(Co)=K[Co(OAc)2]0(1+K[Co(OAc)2]0)−1(k1+k2[Co(OAc)2]0), where at 25 °C K=(5.5±2.0)×104 kg mol−1H=−36±15 kJ mol−1, ΔS=−30±30 J mol−1 K−1), k1=(6.3±0.5)×10−5 s−1H\ eweq=89±8 kJ mol−1, ΔS\ eweq=−27±15 J mol−1 K−1), and k2=(1.17±0.05)×10−1 kg mol−1 s−1H\ eweq=75±3 kJ mol−1, ΔS\ eweq=−11±8 J mol−1 K−1); for the cobalt nitrate system k0(Co)=K1[Co(NO3)2]0(1+K1[Co(NO3)2]0)−1(k1+k2[Co(NO3)2]0+k3K2[Co(NO3)2]02), where at 25 °C k1=(5.1±0.5)×10−5 s−1, k2=(2.0±0.1)×10−1 kg mol−1 s−1, K1=(7.2±2.0)×104 kg mol−1, and k3K2=(1.6±0.15)×102 kg2 mol−2 s−1. Formation constants of sitting-atop complexes were determined dynamically. Mechanisms are proposed for metal ion incorporation and some discussions are made on the difference in the reactivities of acetate and nitrate of cobalt(II) in acetic acid.
  • Kensei Kobayashi, Kitao Fujiwara, Hiroki Haraguchi, Keiichiro Fuwa
    1981 Volume 54 Issue 9 Pages 2700-2704
    Published: 1981
    Released: June 02, 2006
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    A method for the determination of trace zinc has been investigated using hydro-lyase activity of carbonic anhydrase. It was proved theoretically and experimentally that the activation rate of the apo-carbonic anhydrase with zinc is proportional to the amount of zinc present in the solution. Hydro-lyase activity was measured electrochemically using sodium hydrogencarbonate as a substrate. The limit of detection was 0.89 ng/ml or 40 pg of zinc, lower than that obtained by the esterase activity method. Application of the present method to the determination of zinc in real samples has been examined in order to evaluate its analytical feasibility.
  • Masanao Oya, Tomoko Takahashi
    1981 Volume 54 Issue 9 Pages 2705-2707
    Published: 1981
    Released: June 02, 2006
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    The mechanisms of the reactions of 4-alkyloxazolidinediones (1) (N-carboxy α-amino acid anhydrides(NCAs)) with α-amino acid benzyl ester p-toluenesulfonates (2) were investigated in acetonitrile containing triethylamine at low and room temperatures. Two types of reactions were observed: (1) the polymerization of NCAs was initiated with a small amount of 2 to produce polypeptides (6), and (2) the dipeptide benzyl esters (4) were produced by the stepwise reaction of NCAs with the esters. Both the polymerization and the dipeptide formation (1+2) seemed to be initiated by the nucleophilic attack of the amino group of the ester on the C-5 carbon of NCAs. The polymerization proceeded when the side chains of the amino acid esters (R2) were more bulky than those of the NCAs (R1). On the contrary, dipeptide esters were produced when the side chains of the NCAs (R1) were more bulky than those of the esters (R2).
  • Hideki Hirano, Katsuyuki Kurumaya, Masaru Tada
    1981 Volume 54 Issue 9 Pages 2708-2711
    Published: 1981
    Released: June 02, 2006
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    The photolysis of 4′-(2-phenyl-1,2-dioxoethyl)benzo-15-crown-5 in benzene containing 1-dodecanethiol gives benzaldehyde and 4′-formylbenzo-15-crown-5. The formation of the aldehydes was inhibited by the sodium ion, whereas the photolysis of 1-(3,4-dimethoxyphenyl)-2-phenylethanedione was not inhibited by the sodium ion. This inhibition must be due to the decrease in the formation of benzoyl radicals from the triplet excited state of the crown ether derivative. The salt effect was discussed on the basis of the spectral data.
  • Shigeru Oae, Toshikazu Takata, Yong Hae Kim
    1981 Volume 54 Issue 9 Pages 2712-2723
    Published: 1981
    Released: June 02, 2006
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    Formations of peroxy-sulfenate(I), -sulfinate(II), and -sulfonate(III) as intermediates have been confirmed by stripping the peroxy oxygen with three kinds of trapping agents such as sulfoxides, phosphines, and olefins, added in the reaction systems of various organic sulfur compounds with hyperoxide anion (O2\ ewdot). These sulfoxides, phosphines, and olefins were inert to O2\ ewdot alone while electrophilic olefins, such as α,β-unsaturated ketones reacted readily with O2\ ewdot to afford the carboxylic acid. Sulfoxides, added into the reaction system of disulfide, thiosulfinic S-ester, thiosulfonic S-ester, or sulfonyl chloride with O2\ ewdot, were found to be oxidized to the sulfones with peroxysulfur intermediates formed in situ in the system. Phosphines, added into the reaction system of disuflide or sodium thiolate with O2\ ewdot were also oxidized to the phosphine oxides. Not only stilbene and acenaphthylene but also chalcone and its derivatives, placed in the reactions of sulfonyl chloride, sulfinyl chloride and thiosulfonic S-ester with O2\ ewdot were found to be oxidized to the corresponding epoxides. These observations suggest clearly that the intermediary peroxysulfur compounds can act as oxidizing agents which oxidize these trapping agents by the nucleophilic oxygenative oxidation. Similar intermediates were postulated and confirmed in the alkaline autoxidations of thiol and disulfide in which added phosphines and sulfoxides were also found to be oxidized to their oxides. The mechanisms of the reactions of these trapping agents with peroxysulfur intermediates are discussed.
  • Toshihiko Okada, Yoshio Kamiya
    1981 Volume 54 Issue 9 Pages 2724-2727
    Published: 1981
    Released: June 02, 2006
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    The liquid-phase oxidation of methylbenzenes catalyzed by a catalyst system composed of cobalt(II) and copper(II) acetates and sodium bromide was carried out in acetic acid at 150 °C. The corresponding benzyl acetates and benzaldehydes were obtained in high selectivities in most cases. A nuclear-brominated product, i.e., 3-bromo-4-methoxytoluene was also obtained in the oxidation of p-methoxytoluene, which has two different reaction sites, i.e., o-positions to the electron-donating methoxyl substituent and the benzyl position. However, the substitution of the bromide ion for the acetate ion in the catalyst system gave satisfactory selectivities for the side-chain oxidation products. In p-xylene oxidation, α,α′-diacetoxy-p-xylene and p-(acetoxymethyl)benzonic acid were also obtained, as well as p-methylbenzyl acetate, though their amounts were small. The oxidation of polymethylbenzenes was also carried out.
  • Shinkiti Koto, Shigeru Inada, Shonosuke Zen
    1981 Volume 54 Issue 9 Pages 2728-2734
    Published: 1981
    Released: June 02, 2006
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    A new analog of trehalosamine, α-D-galactopyranosyl 2-amino-2-deoxy-α-D-glucopyranoside, was synthesized by the glycosylation of 2,3,4,6-tetra-O-(p-chlorobenzyl)-α-D-galactopyranose with 3,4,6-tri-O-acetyl-2-deoxy-2-(2,4-dinitroanilino)-α-D-glucopyranosyl bromide, using silver perchlorate and tribenzylamine in benzene, followed by chromatographic separation and the subsequent removal of the protecting groups. Similarly, α-D-mannopyranosyl 2-amino-2-deoxy-α-D-glucopyranoside was synthesized. The conformation of the glycoside linkage of these α,α-disaccharides is discussed in relation to the 13C chemical shifts of their anomeric carbons.
  • Toshio Takei, Masaru Matsuoka, Teijiro Kitao
    1981 Volume 54 Issue 9 Pages 2735-2738
    Published: 1981
    Released: June 02, 2006
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    The reaction of 1,4-dihydroxyanthraquinone(DHAQ, 1) with various diamines were carried out in the presence of CuCl2. Primary 1,2-ethylenediamines or 1,2-cyclohexanediamine afforded the ring-closure products, 6-hydroxy-1,2,3,4-tetrahydronaphtho[2,3-f]quinoxaline-7,12-dione derivatives, in good yields of 70–98%. On the other hand, in the cases of N-alkylethylenediamines or 2-(alkylamino)ethanols, the major products were the 2-aminated 1,4-dihydroxyanthraquinones. The direct 2-amination of 1 was greatly inhibited when an alkyl group was introduced to the amino group because of its steric requirement. The role of copper ions, the effect of a steric requirement of the N-alkyl substituent of amines, and the effect of the chain length of alkanediamines in the reaction of 1 with amines were studied. It was proposed that the reaction was initiated by the direct 2-amination of 1 via the copper complex, followed by the intramolecular nucleophilic substitution of the 2-amino group on the 2-alkylamino substituent to give the ring-closure product.
  • Seiichiro Ogawa, Tatsushi Toyokuni, Takashi Kondoh, Yoshihisa Hattori, ...
    1981 Volume 54 Issue 9 Pages 2739-2746
    Published: 1981
    Released: June 02, 2006
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    Several derivatives of pseudo-hexopyranose (5-hydroxymethyl-1,2,3,4-cyclohexanetetrol) with α-gluco, (1,2,4/3,5), and β-gluco, (1,3,5/2,4), configurations were synthesized starting from the compounds obtained by cis-hydroxylation and oxyamination of DL-di-O-acetyl-(1,3/2)-3-bromomethyl-5-cyclohexene-1,2-diol. The 1H NMR chemical shifts of the acetyl methyl protons of the several acetyl derivatives of N-(p-tolylsulfonyl)-pseudoglucosamines are discussed.
  • Tamejiro Hiyama, Masaki Shinoda, Hiroyuki Saimoto, Hitosi Nozaki
    1981 Volume 54 Issue 9 Pages 2747-2758
    Published: 1981
    Released: June 02, 2006
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    A highly regio- and stereoselective five-membered ring annulation involving the acid-treatment of propargyl alcohol dianion adducts of ketones is described. The propargyl alcohol adduct of 2-octanone was converted into 2-methyl-3-pentyl-2-cyclopentenone by treatment with sulfuric acid–methanol (1:1) at 0 °C. As the major product, 1-methylbicyclo[5.3.0]dec-6-en-8-one was produced from 2-methylcycloheptanone. Remarkable regioselective cyclopentannulation was observed in 2-methylcyclohexanone and 2,3-dimethylcyclohexanone wherein 1-methyl- and trans-1,2-dimethyl-substituted bicyclo[4.3.0]non-5-en-7-one (BNO) are produced, respectively. With 3-butyn-2-ol, 2-methylcyclohexanone was converted into the cis-1,9-dimethyl-substituted BNO. 4-Isopropyl-2-methylcyclohexanone was transformed into an 83–85:17–15 mixture of c-3-isopropyl-γ-1,c-9-dimethyl-BNO and its 3-epimer. These results are explained in terms of the conrotatory ring-closure of thermodynamically most favorable hydroxypentadienyl cation intermediates. 3-Methoxycarbonyl-cis-1,9-dimethyl-BNO produced from 4-methoxycarbonyl-2-methylcyclohexanone and 3-butyn-2-ol was successfully transformed into dl-nootkatone by converting the methoxycarbonyl group into isopropenyl of correct stereochemistry followed by ring enlargement. Cyclopentannulation using propargyl alcohol dianion adducts of 2-cycloalkenones is discussed. Annulation takes place regioselectively to give conjugated dienones, e.g., (E)-bicyclo[10.3.0]pentadeca-1(12),2-dien-13-one from 2-cyclododecenone. This product is led to dl-muscopyridine by conjugate 1,6-addition of methyl group followed by ring expansion and finally by aromatization with hydroxylamine hydrochloride.
  • Hiroaki Sawai, Masaji Ohno
    1981 Volume 54 Issue 9 Pages 2759-2762
    Published: 1981
    Released: June 02, 2006
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    Oligoinosinates up to a pentamer were synthesized by the polymerization of inosine-5′-phosphorimidazolide in aqueous solution using Pb2+ ion. 2′–5′ Internucleotide linkage was preferentially formed. The yields of the 2′–5′ linked dimer, trimer, and tetramer were 14.8, 4.5, and 1.6%, respectively. A small amount of linkage isomers of oligoinosinates with 3′–5′ linkage was obtained. The products were characterized by sequential enzyme tests.
  • Keiji Tange
    1981 Volume 54 Issue 9 Pages 2763-2769
    Published: 1981
    Released: June 02, 2006
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    Radioisotopically labeled L-leucine, L-valine, DL-alanine, sodium acetate, and DL-mevalonic acid were incorporated into linalool by the intact plant of Cinnamomum camphora Sieb. var. linalooliferum Fujita and into geraniol and citronellol by that of Pelargonium roseum Bourbon. The uptake of leucine and valine resulted in the preferential location of the radioactivity on the 3,3-dimethylallyl pyrophosphate-derived moiety of these acyclic monoterpenoids, whereas the uptake of alanine resulted in the preferential location on the isopentenyl pyrophosphate-derived moiety, much as in the cases of mevalonic acid and sodium acetate. A biosynthetic pathway leading to the monoterpenoids from the amino acids is discussed.
  • Kiyomi Kakiuchi, Takehito Yonei, Yoshito Tobe, Yoshinobu Odaira
    1981 Volume 54 Issue 9 Pages 2770-2773
    Published: 1981
    Released: June 02, 2006
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    7-Alkylidene-5-oxadispiro[2.0.4.4]dodecan-6-ones, having a cyclopropane ring, were synthesized by the α-alkylidenation of easily available 5-oxadispiro[2.0.4.4]dodecan-6-one. Also, α-alkylidene-γ-butyrolactones, containing an additional hydroxyl group, were prepared. The screening of the biological activities of these γ-lactones gave the interesting results. For instance, α-isopropylidene-γ-lactone exhibited the antiarrhythmia activity in vivo.
  • Atsushi Shimizu, Yoshitaka Sakamaki, Kazufumi Azuma, Hiroshi Kihara, N ...
    1981 Volume 54 Issue 9 Pages 2774-2778
    Published: 1981
    Released: June 02, 2006
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    Rates of dissociation of α-chlorodibenzyl sulfide have been determined by dynamic NMR technique. Examination of the rates at various concentrations of chloroform-d solutions has confirmed that the rates are not dependent on concentration, thus establishing that the NMR measurement affords data of unimolecular dissociation. The salt effect seems to be very small since addition of tetraethylammonium bromide hardly affects the rates of dissociation. Rates of dissociation in o-dichlorobenzene are smaller than in chloroform-d. The main contribution to the decrease in rates is given by the increase in enthalpy of activation, indicating that the hydrogen-bonding ability of chloroform is favorable for ionic dissociation.
  • Yujiro Nomura, Yoshito Takeuchi, Shuji Tomoda, Masato M. Ito
    1981 Volume 54 Issue 9 Pages 2779-2785
    Published: 1981
    Released: June 02, 2006
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    Thermolysis of 4,4-dimethyl-1-(1-phenylvinyl)-5-(1-pyrrolidinyl)-4,5-dihydro-1H-1,2,3-triazole gave 2-methyl-N-(1-phenylvinyl)-1-(l-pyrrolidinyl)-1-propanimine, which reacted as a 2-azabutadiene with electrondeficient dienophiles to afford the corresponding [4+2] cycloadducts. Reactivity and regioselectivity of the cycloaddition reactions were rationalized with the frontier molecular orbital treatment.
  • Masamitsu Ochi, Mitsuyuki Okamura, Hiyoshizo Kotsuki, Iwao Miura, Isao ...
    1981 Volume 54 Issue 9 Pages 2786-2789
    Published: 1981
    Released: June 02, 2006
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    Three new bitter diterpenoids, rabdosianin A, B, and C, have been isolated from the leaves of Rabdosia shikokianus Hara, and their structures, determined by spectroscopic and chemical methods. Complete assignments of the 1H and 13C NMR data are described.
  • Sanji Hagishita, Kaoru Kuriyama
    1981 Volume 54 Issue 9 Pages 2790-2801
    Published: 1981
    Released: June 02, 2006
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    The titled compounds have been prepared from (+)-(9R,10R)-dimethyl 11-oxo-9,10-dihydro-9,10-ethanoanthracene-1,5-dicarboxylate. Their absolute configurations were determined by chemical reaction, and by IR and CD spectra. Although the CD spectra of 2 and 3 (R=NH2) were expected to show an antipodal pattern from analysis of the simple coupling mechanism, they showed approximately the same magnitude of the positive Cotton effect in both regions of the 1Lb and 1La benzenoid transitions. Their CD spectra were calculated by the point-dipole exciton treatment and by the π-SCF approximation using the dipole velocity procedure with and without the charge transfer transition between the aromatic chromophores. Thus, the electric transition dipole moment should not be treated as a point dipole at any place and the rotational strength should be calculated by the dipole velocity procedure since a local magnetic transition dipole moment was produced perpendicular to the benzene ring in the region of the 1Lb transition. The charge transfer transition can not be neglected in the calculation of the MO, though it does not cause the alteration of the sequence of the coupling mode.
  • Akira Fujimoto, Kozo Inuzuka, Ryuichi Shiba
    1981 Volume 54 Issue 9 Pages 2802-2806
    Published: 1981
    Released: June 02, 2006
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    The IR and U V absorption spectra as well as the Raman spectra of monomer and dimer of 2-pyridone were studied. The molecular weight of 2-pyridone in benzene and dimethyl sulfoxide was determined in order to examine the association. 2-Pyridone in nonpolar solvents shows two types of carbonyl stretching vibration bands due to the coexistence of the monomer and dimer. The highest wavelength UV absorption of 2-pyridone in isooctane (2,2,4-trimethylpentane) is ascribed to π-π* electronic transitions of the monomer and dimer. The dimer absorption band appears at a higher wavenumber than that of the monomer by ca. 830 cm−1. The dimer band corresponds to the π-π* transition from the ground 1Ag state to the excited 1Bu state. No π-π* transition absorption from the ground 1Ag state to the excited 1Ag state could be observed because of the g-g Laporte forbiddance in the transition under an assumption of the molecular C2h symmetry.
  • Yukikazu Hattori, Yoshio Kuge, Masao Nakamoto
    1981 Volume 54 Issue 9 Pages 2807-2810
    Published: 1981
    Released: June 02, 2006
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    The relative sensitivities of an electron-capture detector for various polychlorinated biphenyls were measured at different temperatures. Generally, the sensitivities of these compounds become larger as the number of the chloro substituent increases. The temperature dependence of the electron-capture coefficients (K) for these compounds was also determined. These results show that the electron-capture reactions of polychlorinated biphenyls containing less than four chlorine atoms proceed dissociatively, while for four chlorine atoms the reactions proceed either dissociatively or non-dissociatively. For more than five chlorine atoms, the reactions almost always proceed non-dissociatively.
  • Kunio Fukushima, Takeshi Kawai
    1981 Volume 54 Issue 9 Pages 2811-2812
    Published: 1981
    Released: June 02, 2006
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    Raman spectra of 1,3-dimethylurea were measured for the crystalline state, acetone (proton acceptor) solution and water and methanol (proton donors) solutions. Remarkable differences were observed among the spectra of the aqueous solution and those of the acetone solution and the crystal. The difference is interpreted as due to the molecular deformation caused by hydrogen bonding.
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