Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 51 , Issue 3
Showing 1-50 articles out of 64 articles from the selected issue
  • Yoshihisa Matsui, Kazuo Moghida
    1978 Volume 51 Issue 3 Pages 673-676
    Published: 1978
    Released: April 19, 2006
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    The effects of α- and β-cyclodextrins (CD) on the acid dissociations and tautomeric equilibria of sodium 4-(4′-hydroxy-1′-naphthylazo)-1-naphthalenesulfonate (1) and of the conjugate acid (2) of Methyl Orange were spectrophotometrically examined and were compared with the effect of a nonpolar solvent (THF). The apparent pKa values for the dyes decreased with increasing CD concentration. The effect of CD is mainly explained in terms of the hydrophobic interactions between the azo dyes and CD, resulting in a shift in the tautomeric equilibria from less acidic azonium or hydrazone forms to more acidic azo forms of 1 and 2 in an aqueous solution.
  • Yoshiyuki Hirai, Taizo Ito, Yoshio Imamura
    1978 Volume 51 Issue 3 Pages 677-681
    Published: 1978
    Released: April 19, 2006
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    The carbon-13 spin-lattice relaxation times (T1) of the carbons in the alkyl side chains of poly (alkyl methacrylate) (butyl, octyl, dodecyl, and octadecyl), including poly (butyl methacrylate) of low molecular weights, were determined from partially-relaxed Fourier transform spectra. The T1 for polymers of high molecular weights were found to be determined by the internal motion of the side chains, and not by the overall motion of the polymer molecules. The relaxation data indicate that the internal motion of the short side chains (butyl and octyl) is restricted by interactions between the side chains, although this effect was ineffective near the free ends of long chains (dodecyl and octadecyl). These observations are interpreted in terms of the local environment around the side chains.
  • Tsutomu Minato, Shinichi Yamabe, Hiroshi Fujimoto, Kenichi Fukui
    1978 Volume 51 Issue 3 Pages 682-689
    Published: 1978
    Released: April 19, 2006
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    The path of the termination reaction of peroxyl radicals (self-reaction) was studied by means of a perturbational method and its reaction mechanism was elucidated theoretically. It was ascertained from this calculation that the self-reaction of tertiary alkylperoxyl radicals yielding a tetroxide does not have a four-centered transition state with four oxygen atoms of the two peroxyl radicals participating, but has a two-centered transition state with only the terminal oxygen atoms. The self-reaction of primary or secondary alkylperoxyl radicals is found to have a six-centered transition state. The self-reaction of acylperoxyl radicals is also shown to have a six-centered transition state. The mechanism of these self-reactions is clarified in terms of the mode of the particular orbital interaction.
  • Hirosi Matuo, Kimio Hiromoto, Kinsi Motomura, Ryohei Matuura
    1978 Volume 51 Issue 3 Pages 690-693
    Published: 1978
    Released: April 19, 2006
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    The mixed monolayers of long normal chain fatty acids with long normal chain fatty alcohols were studied at various compositions and temperatures. The π-A curves of these systems were measured and the two-dimensional phase diagrams were obtained. The partial molar enthalpy change from the expanded to the condensed state was calculated. It was observed that the phase diagram and enthalpy change of these systems are similar to those previously obtained from the mixed monolayers of long normal chain fatty acids. The miscibility of these systems changes with the increase in the difference of the chain length, as in the systems of fatty acids. It was concluded that the monolayer behavior of the mixed system of an acid and an alcohol is analogous to that of the mixed system of the acid and an acid which contains one more carbon atom in a molecule than the corresponding alcohol.
  • Junichiro Mizusaki, Kazuo Fueki, Takashi Mukaibo
    1978 Volume 51 Issue 3 Pages 694-699
    Published: 1978
    Released: April 19, 2006
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    An improvement was made in the d.c. polarization technique which is used for the measurement of the electronic conductivity of solid electrolytes. In the electrochemical cell, Ag/AgX (X=Br or I)/carbon, the carbon electrode was sealed with AgX in the bottom of a Pyrex tube so that the electrode reaction at the AgX/carbon interface could be suppressed in the steady state. Using the improved d.c. polarization cell, measurement was made of the electronic conductivity of AgI in the temperature range from 330 to 500 °C, and that of AgBr, at temperatures from 375 to 400 °C, as a function of the halogen partial pressure, PX2. It was found that the electronic conduction of α-AgI is p-type and that the electronic conductivity is proportional to PI21⁄2. The electronic conductivity of AgBr was found to be proportional to PBr2−1⁄2 in a low-pressure range of bromine, and proportional to PBr21⁄2 high-pressure range.
  • Akira Kunugi, Shuji Miyoshi, Shigeo Nagaura
    1978 Volume 51 Issue 3 Pages 700-704
    Published: 1978
    Released: April 19, 2006
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    The influence of light excitation on the anodic oxidation of a silver electrode in alkaline solutions has been studied. The experimental results have shown that, in addition to the formation of Ag(II) species by a reaction of Ag(I) species with photo-generated holes, illumination in the Ag2O formation region causes the photogeneration of Ag(I) species at the metal/oxide interface. In the presence of ethylene glycol, the so-called current doubling phenomenon was found. This phenomenon has been interpreted in terms of a mechanism involving a catalytic reaction of the glycol with the photogenerated Ag(II) species, and not by a mechanism involving the oxidation of glycol by the photo-generated holes.
  • Masaru Niitsu, Tatsuya Sekine
    1978 Volume 51 Issue 3 Pages 705-709
    Published: 1978
    Released: April 19, 2006
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    The solvent extraction equilibria of acetic, propionic, and butyric acid and mono-, di-, and trichloroacetic acid (HA), as well as those of oxalic, malonic, succinic, glutaric, and adipic acid (H2A), have been determined in liquid–liquid systems of hexane containing none or a certain amount of trioctylphosphine oxide (E) and an aqueous 1 mol dm3 chloride solution at 25°C. The constants, Kd=[HA]org/[HA], Kdim=[(HA)2]org/[HA]org2, Kex1′=[HAE]org/[HA][E]org, Kex2′=[H2AE2]org/[H2A][E]org2, and β1(org)=[HAE]org/[HA]org[E]org2, have then been determined from the data. It was found that, among the three fatty acids, the value of Kex1′ was higher as the chain length increased, but the values of β1(org) were nearly all the same, while among the chloroacetic acids they were higher as the number of chloride atom increased. The extraction of the dicarboxylic acids with E was not very different, although the number of the –CH2– between the two carboxyl groups changed from zero to four.
  • Hiromitsu Terao, Tsutomu Okuda, Hisao Negita
    1978 Volume 51 Issue 3 Pages 710-712
    Published: 1978
    Released: April 19, 2006
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    Nuclear quadrupole resonance (NQR) frequencies due to 79Br and 127I are examined in phosphorus iodides, PI3 and P2I4, and the complexes PBr3·BBr3, PBr3·BI3, and PI3·BBr3. The quadrupole coupling constants and asymmetry parameters are also derived for 127I in PI3, P2I4, and PBr3·BI3. The resonance lines of PI3 fade out above 257 K, at which temperature a structural phase transition is suggested. The number of resonance lines in P2I4 shows that the molecular symmetry of P2I4 is \bar1 instead of 2/m in its crystal. The similarity of the resonance patterns of the three complexes indicates that they are isomorphous with one another. The electronic structures of the halogens in the compounds mentioned above have been discussed by using the Townes-Dailey theory. On complexing, the electric charge of the halogen atoms in the donor PX3 decreases due to the polarization of pσ bonds, whereas that of the halogen atoms in the acceptor BY3 increases owing to the backdonation through pπ bonds.
  • Koichiro Nakanishi
    1978 Volume 51 Issue 3 Pages 713-717
    Published: 1978
    Released: April 19, 2006
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    The validity of the plot, isoviscous diffusion coefficient D1η2 vs. molar volume V2, where D1 is the diffusion coefficient of solute at infinite dilution, η2 the viscosity coefficient of solvent, and V2 the molar volume of solvent, proposed by Hammond and Stokes for carbon tetrachloride, was examined and confirmed with several solutes. General features of the behavior of diffusivity in dilute solution are discussed in terms of solvent association, complex formation and other factors. The experimental results for iodine are given.
  • Mikio Hoshino, Hajime Akimoto, Michio Okuda
    1978 Volume 51 Issue 3 Pages 718-724
    Published: 1978
    Released: April 19, 2006
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    Photochemical oxidation of benzene, toluene, and ethylbenzene initiated by OH radicals in the presence of NO and NO2 was studied in the air by using a 67 dm3 reaction chamber made of Pyrex glass. OH radicals were produced by photochemical decomposition of nitrous acid, the products being phenol and nitrobenzene for benzene; cresols, benzaldehyde, m- and p-nitrotoluenes, and benzyl nitrate for toluene; ethylphenols, benzaldehyde, acetophenone, and m- and p-nitroethylbenzene for ethylbenzene. The reaction mechanisms are proposed based on the addition of OH radicals to aromatic rings and the hydrogen abstraction of OH radicals from alkyl groups.
  • Keiichi Horigome, Shun-ichi Hirokami, Shin Sato
    1978 Volume 51 Issue 3 Pages 725-728
    Published: 1978
    Released: April 19, 2006
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    The γ-radiolyses of liquid nitrogen solutions of hydrogen, methane, and ethane have been reinvestigated. A complete survey of nitrogen-containing products has been attempted. The nitrogeneous compounds observed were ammonia (0.7) and hydrogen azide (0.02) in the case of hydrogen, ammonia (0.3), hydrogen cyanide (0.1), methyl azide (0.01), and a polymer in the case of methane, and ammonia (0.3), hydrogen cyanide (0.05), acetonitrile (0.04), ethyl azide (0.01), and a polymer in the case of ethane. The values in parentheses are the G-values obtained at optimum conditions. The hydrolysis of the polymer obtained with methane gave formaldehyde in amounts which correspond to the fact that the G-value of the nitrogen atoms which were converted into the polymer is about 1.0. In order to explain these results, possible reaction mechanisms are discussed.
  • Kohzaburo Yamamoto, Takeshi Takemura, Hiroaki Baba
    1978 Volume 51 Issue 3 Pages 729-732
    Published: 1978
    Released: April 19, 2006
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    Fluorescence and phosphorescence spectra of quinoxaline in isooctane (2,2,4-trimethylpentane) have been measured under fluid conditions. The fluorescent emission with a spectral maximum at 410 nm is assigned to the 1(n,π*)→S0 fluorescence of quinoxaline. A new phosphorescence spectrum appears in a wavelength region longer than 520 nm as the concentration of quinoxaline increases, in addition to the phosphorescence spectrum of the monomer. From the results of photostationary and transient experiments on the concentration and/or temperature dependence of phosphorescence, it has been confirmed that the phosphorescence consists of two components attributable to the monomer and the excimer.
  • Kojiro Kan, Kunio Miki, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1978 Volume 51 Issue 3 Pages 733-740
    Published: 1978
    Released: April 19, 2006
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    The molecular structures of [PdCl2{(Me2neoMen)P}2] and [PdCl2{(Me2Men)P}2], asymmetric hydrosilylation catalysts of olefin, were determined by means of X-ray diffraction. Both complexes form yellow prismatic crystals. The former belongs to the monoclinic system: a=13.512(5), b=13.082(1), c=8.472(1) Å, and β=97.00(2)°, space group P21 with Z=2; the latter belongs to the tetragonal system: a=9.662(1) and c=32.459(2) Å, space group P43212 with Z=4. Both structures were determined by the heavy atom method and have been refined anisotropically by a least-squares procedure (R=0.0697 for 2606 non-zero reflections for the former and R=0.0713 for 1388 non-zero reflections for the latter). The former molecules is not iso-structural with its nickel analog. The central palladium atom has trans-square planar geometry [Pd–Cl 2.304(5) and 2.297(5), Pd–P 2.344(4) and 2.361(5) Å]. The molecule has an approximate two-fold symmetry around the normal to the coordination plane. The neomenthyl groups are on the same side of the co-ordination plane. The latter molecule has exact C2 symmetry: the two-fold axis passes through the Cl(1), Pd, and Cl(2) atoms which lie on the co-ordination plane. The geometry around the palladium slightly deviates from the trans-square planar [Pd–Cl 2.296(9) and 2.267(9) Å and Pd–P 2.310(6) Å]. The menthyl groups are located on either side of the co-ordination plane.
  • Ken-ichi Kowari, Shin Sato
    1978 Volume 51 Issue 3 Pages 741-747
    Published: 1978
    Released: April 19, 2006
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    The spatial distribution of secondary electrons produced in the γ-radiolysis of water in the liquid phase has been theoretically calculated. The method consists of the combination of the procedure previously developed for the calculation of the G-value of electrons with the theory proposed by Fr\ddotohlich and Platzman for the slowing down of electrons in polar liquids. The G-value of the ion-pairs initially produced was calculated to be 6.8 on the assumption that the binding energies of electrons in water are equal to those in solid water at 77K. 27% of the ion-pairs were generated in isolated spurs. Another 27% of the ion-pairs were generated in condensed spurs, each of which contains more than one hundred ion-pairs. The other ion-pairs formed less condensed spurs, each of which contains from 2 to 100 ion-pairs. A new definition was given for the classification of spurs: isolated spurs, blobs, and short tracks; the original proposal was by Mozumder and Magee. The diameter of the isolated spur was estimated to be about 100 Å. The distribution of the distance between the parent positive ion and the thermalized electron in the isolated spur was well expressed by the function proposed by Abell and Funabashi, except at very short distances.
  • Yoshiki Ogawa, Shuji Imazeki, Hiroko Yamaguchi, Hiroatsu Matsuura, Iss ...
    1978 Volume 51 Issue 3 Pages 748-767
    Published: 1978
    Released: April 19, 2006
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    The Raman and infrared spectra of 1-chloro-, 1-bromo-, and 1-iodopropanes, CH3CH2CH2X (X=Cl, Br, and I), and 1-chloro-, 1-bromo-, and 1-iodobutanes, CH3CH2CH2CH2X (X=Cl, Br, and I), were measured for the gaseous, liquid, glassy, and crystalline states. The normal vibration frequencies were calculated, a consistent set of force constants explaining the frequencies of basic halogenoalkanes being assumed. The rotational isomerism was studied on the basis of the spectral observations and the normal coordinate calculations. The enthalpy differences among the rotational isomers were examined.
  • Susumu Kohata, Shigeyoshi Sakaki, Akira Ohyoshi
    1978 Volume 51 Issue 3 Pages 768-772
    Published: 1978
    Released: April 19, 2006
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    INDO-type UHF-MO calculations were carried out for Ru(III)-ammine complexes in order to investigate their electronic structures and bonding nature. It was revealed that the ground state of RuX(NH3)52+(X=F, Cl, Br, or I) is the 2E state and that that of cis-RuX2(NH3)4+ is the 2A1 state; in RuX(NH3)52+, the odd electron exists not on the dxy orbital but on the dxz or dyz orbital which interacts with the pπ orbital of the halide ligand, and in cis-RuX2(NH3)4+, this electron exists not on the dxz or dxy orbital but on the dyz orbital which interacts with the pπ orbitals of the two halide ligands. Concenring the bonding nature, the following results were obtained: (1) the strength of the Ru–NH3 bond in these complexes increases in the order, cis-RuX2(NH3)4+<RuX(NH3)52+<Ru(OH2)(NH3)53+<Ru(NH3)63+; (2) in the aqua-ammine complex, the Ru–OH2 bond is weaker than the Ru–NH3 bond; and (3) in the halogeno-ammine complexes, the trans-Ru–NH3 bond is weaker than the cis-Ru–NH3 bond. MO calculations were also carried out for some distorted states of RuCl(NH3)52+ From these results, a discussion is presented on the relation between the thermal reaction product and the reaction mechanism; cis-RuCl2(NH3)4+ is expected to be produced via an associative reaction mechanism, while the trans-form product is expected to result from a dissociative mechanism.
  • Joichi Ueda
    1978 Volume 51 Issue 3 Pages 773-776
    Published: 1978
    Released: April 19, 2006
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    Semimethylxylenol Blue (SMXB) reacts with iron(III) and aluminium to form water-soluble colored complexes. The colored solution of the iron(III) complex shows a maximum absorption at 580–581 nm, while that of the aluminium complex shows it at 554–555 nm. The absorbances of the solutions are constant over the pH range from 1.2 to 1.5 and from 2.5 to 2.9, respectively. Beer’s law is obeyed up to 1.4 μg cm−3 of iron(III) and 1.0 μg cm−3 of aluminium. Their molar extinction coefficients are 3.38×104 and 2.91×104, respectively. As a result of the investigation of the composition of the iron(III) or aluminium complex, the mole ratio of metal and SMXB was estimated to be 1 : 1. Among the 45 diverse ions examined, gallium, tin(IV), bismuth(III), zirconium, and vanadium(V) interfered with iron(III) determination, and gallium, indium, bismuth(III), scandium, titanium(IV), zirconium, vanadium(V), iron(III), fluoride, and oxalate interfered with aluminium determination. Consecutive determination of iron(III) and aluminium was also studied.
  • Takashi Maekawa, Niro Kikuchi, Noriyuki Fukuda, Toshio Yokokawa
    1978 Volume 51 Issue 3 Pages 777-779
    Published: 1978
    Released: April 19, 2006
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    The S Kα spectra of the sulfur compounds were measured. The S Kα energies of metal sulfides were less than that of the pure sulfur in accordance with the theoretical prediction. The S Kα shift for CaS (−0.239 eV) is the largest among those of metal sulfides examined in this study. In the sulfur+selenium binary mixtures, the S Kα energy goes more negative than that of sulfur with increasing the selenium content. These results can be interpreted in terms of the electronegativity of the counter atoms.
  • Takashi Maekawa, Niro Kikuchi, Shigekazu Sumita, Toshio Yokokawa
    1978 Volume 51 Issue 3 Pages 780-782
    Published: 1978
    Released: April 19, 2006
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    The Si Kα emission lines of the several silicon compounds and binary silicate (Na, K, Rb, and B-silicates) glasses were measured. In the binary silicates, negative energy shifts from that of SiO2 were observed. They were interpreted as indicating a relative decrease of the quantity of charge transfer from silicon to oxygen, when more electropositive elements like alkali metals are located on the next nearest neighbor positions of the silicon atoms. The Si Kα shifts of silicate glasses have a good correlation with the basicity of their melts.
  • Kosuke Izutsu, Toshio Nakamura, Toshihiko Kitano, Chieko Hirasawa
    1978 Volume 51 Issue 3 Pages 783-789
    Published: 1978
    Released: April 19, 2006
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    The liquid junction potential (ljp) between water and organic solvents was investigated by measuring the emfs of cells with free-diffusion junctions of various electrolyte solutions. In most experiments, the concentration of the electrolyte on one side of a junction was kept much larger than that on the other side (c MX in S⁄⁄c′ M′X′ in S′; S or S′ is H2O and c>>c′; thus the ljp was mainly determined by MX. The ljp may practically be expressed by the sum of Ej,ion (concn)(I), Ej,ion (ion-solv.)(II), and Ej,solv. (III). I and II are contributions from ionic species: I is the concentration term, which can be estimated approximately from the Henderson equation, and II is the term due to the difference in ionic solvations in S and S′. III is the contribution from the transfer of solvent molecules. The sum of II and III for the case in which S=H2O is approximately equal in absolute value but opposite in sign to that for the case in which S′=H2O. The change of II with the anion X is in linear relation with free energy of transfer of the anion from S to S′. The change of III with the bridge solvent is also a linear function of the heat (or free energy) of solution of S into S′. The rate of the change with the heat of solution can be divided in two classes by the species of the cation M+: the rate for R4N+ ions is just a half of that for such ions as Li+, Na+, Mg2+, and Ba2+. The effect of the mixed bridge electrolytes and the mixed bridge solvents was also examined.
  • Osamu Nagano, Akiko Kobayashi, Yukiyoshi Sasaki
    1978 Volume 51 Issue 3 Pages 790-793
    Published: 1978
    Released: April 19, 2006
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    Ammonium bromide forms a 1 : 1 complex with cyclic polyether “18-crown-6.” The crystals of C12H24O6·NH4Br·2H2O are orthorhombic, with the space group of Pnam and with cell constants of a=10.002(3), b=12.716(4), c=15.073(4) Å, and Z=4. The structure was solved by the conventional heavy-atom technique and refined by the full matrix least-squares method to R=0.099 for 1033 independent reflections. The 18-crown-6 has a conformation with a pseudo D3d symmetry. The ammonium cation is displaced by 1.00 Å from the mean oxygen plane of the 18-crown-6 and interacts with the nearest bromide anion. The relationship between the cation and the 18-crown-6 resembles those of the C12H24O6·RbNCS and C12H24O6·CsNCS complexes. On the difference Fourier maps, four electron-density peaks were detected at reasonable positions for the hydrogen atoms of the amonium cation.
  • Yasushi Inoue, Masamichi Tsuji
    1978 Volume 51 Issue 3 Pages 794-799
    Published: 1978
    Released: April 19, 2006
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    The effects of 60Co γ-ray irradiation and of heat treatment in air have been studied on the properties of the hydrous titanium oxide ion exchanger. The ion-exchange capacity of the sodium form did not change at all, while that of the hydrogen form decreased a little, by the exposure of 5.2×108 R. The color of the exchanger, initially white, turned yellow upon irradiation. This exchanger was stable against heat treatment up to around 80 °C; thereafter the exchange capacity gradually decreased with the temperature until 324 °C, where it was abruptly reduced to about a quarter of the initial value. The examination of the titration curves showed that the most acidic exchange site was weaker than less acidic sites against heat treatment. The structural formula of this hydrous titanium oxide ion exchanger has been suggested on the basis of the ion-exchange capacity, the thermal decomposition curves, and such auxiliary data as the X-ray diffraction and the infrared spectra.
  • Akira Endo, Masayuki Watanabe, Sadayuki Hayashi, Kunio Shimizu, Gen P. ...
    1978 Volume 51 Issue 3 Pages 800-804
    Published: 1978
    Released: April 19, 2006
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    In tetraethylammonium perchlorate-acetonitrile solution, [Ru(acac)3] was reversibly reduced at the dropping mercury electrode to [Ru(acac)3] with a conditional electrode reaction rate-contsant estimated to be ca. 0.2 cm s−1 or larger. The reduced form was stable in the solution under an inert gas atmosphere. In aqueous solutions, [Ru(acac)3] was reduced reversibly when the depolarizer concentration was less than 0.07 mol m−3 at 25 °C. At higher depolarizer concentrations, [Ru(acac)3] molecules were adsorbed onto the mercury surface, and the free molecules in solution were reduced through the adsorbed layer at a smaller rate; the adsorbed layer was removed at a certain negative potential, and the reversible reduction took place normally at the bare surface. The difference between reversible half-wave potentials observed in acetonitrile and aqueous solutions was discussed in terms of solvation energies of the oxidized and reduced forms.
  • Kazumasa Ueda
    1978 Volume 51 Issue 3 Pages 805-810
    Published: 1978
    Released: April 19, 2006
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    The stability constants and thermodynamic functions for 1:1 adduct formation of unidentate heterocyclic bases with copper(II) β-diketonates were determined in non-aqueous solvents by the spectrophotometric method. The main factors controlling the stability of the adducts were investigated and the bases were classified into two groups in adduct formation from the plots of the stability constants against pKH values of the bases: steric hindered and unhindered bases. Large negative entropy changes were observed for pyridine, β-picoline, and γ-picoline; these were ascribed to the π-bond character of the adduct bonds. A solvent effect was observed; the order of increasing adduct stability was as follows: acetone <butyl acetate <4-methyl-2-pentanone <chloroform <nitrobenzene <toluene \simeq benzene <chlorobenzene. This order agreed with the decreasing order of the solvent-chelate interaction and of the solvent-base interaction. In all cases, the adducts were stabilized by large exothermic enthalpy changes. Moreover, the introduction of a CF3 group into β-diketones also brought about a considerable entropy change which promoted the stabilization of the chelate. The effect of the other terminal groups was not clearly observed.
  • Ryoji Noyori, Masashi Yamakawa, Wataru Ando
    1978 Volume 51 Issue 3 Pages 811-814
    Published: 1978
    Released: April 19, 2006
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    The geometry and electronic properties of methylene, methylcarbene, carboxycarbene, phenylcarbene, trimethylsilylcarbene, silylcarbene, carboxysilylcarbene, and phenylsilylcarbene have been determined by MINDO/3 calculation. Introduction of a silyl group results in considerable decrease in ionization potential of carbenes. The electron affinity is increased to some extent by such substitution. The computation suggests a bent geometry for optimized triplet trimethylsilylcarbene structure, in conflict with a recent postulate that the ground-state molecule has an essentially linear structure.
  • Ikuko Wakeshima, Ichiro Kijima
    1978 Volume 51 Issue 3 Pages 815-817
    Published: 1978
    Released: April 19, 2006
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    The reaction of Sn–OC bond-containing tin(II) compounds with ethyl isocyanate was investigated. From the νNC0 absorption bands, it is recognized that the reactivity, in terms of tin(II) compounds, decreases in the order: bis[2-(dimethylamino)ethoxo]tin(II) > bis[o-(ethoxycarbonyl)phenolato]tin(II) > di(phenolato)tin(II)>bis(ethoxycarbonylacetonato)tin(II)>bis(3-ethoxycarbonyl-2-pentanoato)tin(II)>bis(1-phenylbutane-1,3-dionato)tin(II)>bis(dibenzoylmethanato)tin(II). Bis[2-(dimethylamino)ethoxo]tin(II), bis[o-(ethoxycarbonyl)phenolato]tin(II), and di(phenolato)tin(II) yielded triethyl isocyanurate as a main product from reactions with ethyl isocyanate, while bis(ethoxycarbonylacetonato)tin(II), bis(3-ethoxycarbonyl-2-pentanoato)tin(II), bis(1-phenylbutane-1,3-dionato)tin(II), and bis(dibenzoylmethanato)tin(II) gave mixtures of the isocyanurate and 6-ethylimino-1,3,5-triethylhexahydro-1,3,5-triazine-2,4-dione. The mechanism for the formation of these products is discussed.
  • Koshiro Goda, Fumito Hanafusa, Naoki Inamoto
    1978 Volume 51 Issue 3 Pages 818-820
    Published: 1978
    Released: April 19, 2006
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    Unsymmetrical sulfides were prepared by the reactions of diphenylphosphinodithioate esters with organolithiums in tetrahydrofuran (THF) at −78 °C or at room temperature in fairly good or excellent yields. Similarly, methylene bis(diphenylphosphinodithioate) gave bis(alkylthio)methanes by reactions with organolithiums in good yields. The use of bad-smelling thiols is avoided and the phosphorus part can be recycled after sulfurization and esterification. Allyl diphenylphosphinodithioate gave allylbenzene via SN2(C) reaction upon treatment with phenylmagnesium bromide in refluxing THF.
  • Takeo Shimidzu, Akira Murakami, Yoshiyuki Konishi, Manabu Minami
    1978 Volume 51 Issue 3 Pages 821-825
    Published: 1978
    Released: April 19, 2006
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    The interactive properties of positively charged polynucleotide analogs, such as nucleic acid base-binding poly(4-vinylpyridine)s and their derivatives, with nucleotides have been investigated. The interactions of the positively charged polynucleotide analogs such as N-alkylated poly(4-vinylpyridine)s with 9-(ω-chloroalkyl)adenine and of N-alkylated poly(4-vinylpyridine) with 1-(2-bromoethyl)thymine with nucleotides were attributed predominantly to a base-base stacking under reinforcement by the coulombic attractive force. The purinepurine base interaction was found to be stronger than the purine-pyrimidine and the pyrimidine-pyrimidine interactions. The interaction was reduced by an increase in the ionic strength. The higher the charge density of the nucleotide was, the stronger was the interaction observed. On the other hand, a cross-linked positively charged polynucleotide analog such as N-alkylated cross-linked poly(4-vinylpyridine) with 9-(2-chloroethyl)adenine showed considerable selective interaction with the complementary nucleotide, uridine-5′-phosphate (pU), in both aqueous and pyridine solutions.
  • Akitami Ichihara, Makio Kobayashi, Kengo Oda, Sadao Sakamura
    1978 Volume 51 Issue 3 Pages 826-829
    Published: 1978
    Released: April 19, 2006
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    Treatment of quinone epoxide–cyclopentadiene adducts with sulfuric acid gave abnormal ring opening products, whose structures were determined by the spectral data and identification of the degradation product. Regioselectivity of the reaction was confirmed. The mechanism of the reaction is discussed.
  • Teruaki Yamada, Yoshio Kamiya
    1978 Volume 51 Issue 3 Pages 830-834
    Published: 1978
    Released: April 19, 2006
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    The ligand effect of 2,2′-bipyridine on the rate of the decomposition of 1,2,3,4-tetrahydro-1-naphthyl hydroperoxide catalyzed by cobalt(II) decanoate in chlorobenzene was kinetically studied and compared with the redox potentials and the spectral data of cobalt(II) complexes. The activity of the anhydrous cobalt(II) decanoate increased by a factor of from three to seven by the addition of 2,2′-bipyridine when the molar ratio of 2,2′-bipyridine to cobalt was 0.25 to 2. It was found that the catalytic activity of the anhydrous cobalt(II) decanoate-2,2′-bipyridine complex shows a remarkable maximum value at the molar ratio of 2,2′-bipyridine to cobalt of 0.5. This novel finding can be explained on the basis of the redox potential measured by cyclic voltammetry in dichloromethane, the IR data, and the structure of the catalyst. The coordination of 2,2′-bipyridine causes the redox potential to change from 0.80–0.84 V to 0.60–0.64 V (vs. SCE) and also weakens the Co–O(decanoate) bond strength, resulting in a facile coordination of hydroperoxide to the cobalt ion as well as the acceleration of cleavage of hydro-peroxide. The maximum activity was explained by the proposed structure of the cobalt(II) decanoate-2,2′-bipyridine (1 : 1/2) complex with a fairly low redox potential and a vacant coordination site.
  • Masakazu Yamashita, Yoshihisa Watanabe, Take-aki Mitsudo, Yoshinobu Ta ...
    1978 Volume 51 Issue 3 Pages 835-838
    Published: 1978
    Released: April 19, 2006
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    The Knoevenagel condensates prepared from 2,4-pentanedione with aldehydes were allowed to react with the tetracarbonylhydridoferrate(0) anion in ethanol to give reductively deacylated monoketones in high yields. However, the exclusive reduction of the α,β-unsaturated double bond of the same condensates was encountered when the reaction was carried out in such a solvent as tetrahydrofuran and acetone. The Knoevenagel condensates, derived from the reaction of ethyl acetoacetate and/or ethyl benzoylacetate with aldehydes, were simply reduced even in ethanol. The reaction mechanism is briefly discussed.
  • Masaru Tada, Hidetoshi Harada, Kyo Miura
    1978 Volume 51 Issue 3 Pages 839-841
    Published: 1978
    Released: April 19, 2006
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    The 1,3-dicarbonyl compound, with an electro-negative substituent, 3-cyano-2,4-pentanedione, gives the photoaddition product with cyclohexane. The adduct must be formed by the retro-aldol reaction of the “2+2” cycloaddition product and the hemiacetalization of the resulting 1,5-dicarbonyl compound. Enol ether, with a lower ionization potential, does not photoadd to 3-cyano-2,4-pentanedione but quenches the photoaddition between 3-cyano-2,4-pentanedione and cyclohexene. The solvent effect, the ionization potential, and quenching experiments show that the photoaddition follows a process involving a singlet excited complex.
  • Toshifumi Hirata, Takayuki Suga
    1978 Volume 51 Issue 3 Pages 842-849
    Published: 1978
    Released: April 19, 2006
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    Aloenin, a new bitter glucoside with an inhibitory activity for the gastric juice secretion of rats, was isolated from the leaves of Aloe arborescens Mill. var. natalensis Berger, and the structure was confirmed to be 4-methoxy-6-(2-β-D-glucopyranosyloxy-4-hydroxy-6-methylphenyl)-2-pyrone by means of chemical, spectroscopic, and X-ray crystallographic methods. Ambiguity in the assignment of 2-pyrone-ring carbon signals was clarified by examination of the 13C-NMR spectra of aloenin and the related compounds.
  • Tateaki Wakamiya, Katsutoshi Mizuno, Tatsuzo Ukita, Tadashi Teshima, T ...
    1978 Volume 51 Issue 3 Pages 850-854
    Published: 1978
    Released: April 19, 2006
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    Cyclic guanidino amino acid, capreomycidine, is a component of antituberculous peptides, capreomycin and tuberactinomycin N and O. Its epimer was also found in protease inhibitors, chymostatin and elastatinal. A new synthetic approach to DL-capreomycidine via β-hydroxyornithine was studied for the purpose of total synthesis of capreomycidine and epicapreomycidine of natural forms or its hydroxy derivative, tuberactidine.
  • Tetsuo Suami, Kin-ichi Tadano, Mitsukuni Ayabe, Yasufumi Emori
    1978 Volume 51 Issue 3 Pages 855-861
    Published: 1978
    Released: April 19, 2006
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    Eight carbocyclic puromycin analogs, in which the furanosyl ring of puromycin is replaced with a cyclopentyl system, were synthesized. Their minimum degeneration concentration (MDC) was determined against HeLa cells in a tissue culture. The two analogs were found to be remarkably active.
  • Hajime Matsushita, Yasuko Tsujino, Masao Noguchi, Masahiko Saburi, Sad ...
    1978 Volume 51 Issue 3 Pages 862-865
    Published: 1978
    Released: April 19, 2006
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    The temperature dependence of asymmetric transformation of 2-phenylpropanal via achiral enamine salt of d-10-camphorsulfonic acid was examined. The relation between the rotation of 2-phenylpropanal obtained and reaction temperature showed a notable change in specific rotation of the aldehyde obtained. Two courses are postulated for the optical activation.
  • Hiromitsu Masada, Tadahide Sakajiri
    1978 Volume 51 Issue 3 Pages 866-868
    Published: 1978
    Released: April 19, 2006
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    Di-t-butyl ether was prepared in 6–73% yields by the reactions of t-butyl halide with Ag2CO3, Ag2O, HgO, ZnO, ZnCO3, PbO2, Cu2(CO3)(OH)2, and Tl2O3 at 20–65 °C in hydrocarbons under nitrogen. Similar reactions gave seven new hindered di-t-alkyl ethers: di-t-pentyl ether, bis(1,1-dimethylbutyl) ether, bis(1-ethyl-1-methylpropyl) ether, bis(1,1-dimethylpentyl) ether, bis(1-ethyl-1-methylbutyl) ether, bis(1,1-diethylpropyl) ether, and bis(1,1-dimethylhexyl) ether. The yield of di-t-alkyl ether decreased as the t-alkyl group became bulky. A slight difference in the skeletal structure of the t-alkyl halide markedly influences the substitution. The reaction pathways are elucidated on the basis of the experimental results.
  • Mitsuhiro Kinoshita, Masaki Awamura
    1978 Volume 51 Issue 3 Pages 869-871
    Published: 1978
    Released: April 19, 2006
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    A prototypic compound of pyridomycin, 6-(3-hydroxypicolinoylamino)-5-methyl-8-aza-1,4-dioxacyclododecane-3,7,12-trione (11), was synthesized. 4-(Benzyloxycarbonylamino)butyric acid was coupled with t-butyl glycolate in the presence of DCCI and pyridine to afford t-butyl [4-(benzyloxycarbonylamino) butyryloxy] acetate (4). De-t-butylation of 4 followed by condensation with N-t-butoxycarbonyl-L-threonine benzyl ester by the DCCI method gave O-[{4-(benzyloxycarbonylamino)butyryloxy}acetyl]-N-t-butoxy-carbonyl-L-threonine benzyl ester (6). Deprotection of 6 followed by cyclization with Woodward’s reagent K afforded 6-(t-butoxycarbonylamino)-5-methyl-8-aza-1,4-dioxacyclododecane-3,7,12-trione (21% yield), which was transformed into the title compound 11.
  • Takayuki Suga, Toshifumi Hirata
    1978 Volume 51 Issue 3 Pages 872-877
    Published: 1978
    Released: April 19, 2006
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    The 14C- and 3H-labeling patterns in aloenin biosynthesized by uptake of acetate-1-14C, malonate-2-14C, phenylalanine-1-14C and -3-14C, methionine-methyl-14C, and glucose-3-3H to Aloe arborescens var. natalensis demonstrated that the carbon skeleton of aloenin is arisen via a biological polyketide by the acetate-malonate pathway and the O-methyl group originates from methionine. Further, feeding experiments of 3H/14C-doubly labeled 4-methoxy-6-(2,4-dihydroxy-6-methylphenyl)-2-pyrone and 5-(2-β-D-glucopyranosyloxy-4-hydroxy-6-methylphenyl)-3,5-dioxopentanoic acid in the Aloe plant revealed that an immediate intermediate is the pyrone derivative and not the dioxopentanoic acid derivative. Aloenin was demonstrated to be biosynthesized in such a way that the first formation of the pyrone by cyclization of the biological polyketide and then O-methylation of the cyclized intermediate is followed by introduction of a glucose molecule into the pyrone derivative.
  • Takashi Yamada, Katsumi Takashima, Toshifumi Miyazawa, Shigeru Kuwata, ...
    1978 Volume 51 Issue 3 Pages 878-883
    Published: 1978
    Released: April 19, 2006
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    Bottromycins B1 and B2, peptide antibiotics, were synthesized according to the structures proposed by Nakamura et al. B1 was obtained by the condensation of the imidate, Piv–Tle–Val–ImPro–OEt·HCl with the ester, H–Gly–Phe(βMe)–β-Tha–OH in the presence of Et3N, and B2 by the replacement of the Z group of Z–Tle–Val–ImPro–Gly–Phe(βMe)–β-Tha–OMe by the trans-4-methyl-2-pentenoyl group. The structures of the synthetic B1 and B2 were confirmed by elemental analyses, amino acid analyses, and Cl-mass spectra. However, the synthetic bottromycins differed from the natural ones in many respects, e.g., IR spectra, behavior in TLC, and pKa values. Most significantly, no antimicrobial activities were detected in the synthetic B1. On the basis of these results, it is concluded that the structures proposed by Nakamura et al. for bottromycins are erroneous and should be revised.
  • Tadashi Honda, Tatsushi Murae, Takahiko Tsuyuki, Takeyoshi Takahashi
    1978 Volume 51 Issue 3 Pages 884-888
    Published: 1978
    Released: April 19, 2006
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    Methyl 2α,3β,23-triacetoxy-13αH-olean-18-en-28-oate (4) and methyl 2α,3β-diacetoxy-13αH-olean-18-en-28-oate (7) were obtained from methyl 2α,3β,23-triacetoxy-19-oxoolean-12-en-28-oate (2) and from methyl 2α,3β-diacetoxy-19-oxoolean-12-en-28-oate (5), respectively, by the forced Wolff-Kishner reduction and subsequent acetylation and methylation. Methyl 2α,3β-diacetoxy-13βH-olean-18-en-28-oate (10), prepared from methyl 2,3-di-O-acetylarjunate (13) via methyl 2α,3β-diacetoxy-19α-hydroxy-12-oxooleanan-28-oate (18) and methyl 2α,3β-diacetoxy-19α-hydroxyoleanan-28-oate (19), was shown to be not identical with 7. This led to a 13αH-olean-18-ene structure for 7.
  • Katsuyuki Ogura, Nobuko Katoh, Gen-ichi Tsuchihashi
    1978 Volume 51 Issue 3 Pages 889-890
    Published: 1978
    Released: April 19, 2006
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    Treatment of methyl (methylthio)methyl sulfoxide (1) with sodium hydride gave bis(methylthio)(methylsulfinyl)methane (3) which might be formed by abnormal attack of the carbanion (2) of 1 on the sulfide linkage of 1. The additon of butyl iodide to this system completely suppressed the formation of 3, showing that 2 reacts faster with butyl iodide than with 1. The mechanism to account for these phenomena is discussed.
  • Jun-ichi Hayami, Tohru Koyanagi, Nobuhisa Hihara, Aritsune Kaji
    1978 Volume 51 Issue 3 Pages 891-896
    Published: 1978
    Released: April 19, 2006
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    Substrate-nucleophile association was found between substituted chloromethanes (ArXCH2Cl: X=NONE, S, SO, SO2, and CO) and halide ion (Cl, Br, and I) in dipolar aprotic solvent. The equilibrium constant (K), limiting shift (Δc), the enthalpy of formation (ΔH°), and the entropy of formation (ΔS°), for complexing were determined by NMR measurement. The measurement of spin-lattice relaxation time (T1) gave an information on the conformation of this complex. Halide ion seems to locate closest to α-methylene protons at the site of potential SN2 reaction.
  • Kin-ichi Tadano, Sumio Horiuchi, Tetsuo Suami
    1978 Volume 51 Issue 3 Pages 897-900
    Published: 1978
    Released: April 19, 2006
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    Six carbocyclic analogs of uridine and thymidine in which the pentofuranosyl groups are replaced by a carbocyclic cyclopentane system have been synthsized. Their biological activities were determined against HeLa S3 cells.
  • Yuzuru Masuda, Akira Arase
    1978 Volume 51 Issue 3 Pages 901-904
    Published: 1978
    Released: April 19, 2006
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    In the reaction of trialkylborane with lead(IV) acetate or phenyliodoso acetate in benzene, about two thirds of the alkyl groups of trialkylborane were converted to the corresponding alkyl acetate without any isomerization of the alkyl group. Lead(IV) acetate reacted preferentially with the secondary alkyl group, while phenyliodoso acetate reacted only with the primary alkyl group. In either reaction, one mole of oxidizing agent was consumed for the formation of one mole of alkyl acetate.
  • Masao Tokuda, Yasuyuki Watanabe, Mitsuomi Itoh
    1978 Volume 51 Issue 3 Pages 905-908
    Published: 1978
    Released: April 19, 2006
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    Photochemical reaction of ethyl 2-oxo-1-cyclohexanecarboxylate (3) in methanol gave ethyl methyl heptanedioate, trans- and cis-ethyl 7-oxo-2-heptenoate, and ethyl 7-oxo-3-heptenoate in 25, 7, 8, and 21% yields, respectively. Photochemical reactions of 3 in ethanol, isopropyl alcohol, and t-butyl alcohol gave the corresponding ω-alkoxycarbonyl esters. Other 2-(alkoxycarbonyl)-cyclopentanones and -cycloheptanone underwent similar reactions to give the corresponding ω-alkoxycarbonyl esters. Photochemical reactions of 2-cyanocyclohexanones in methanol similarly gave ω-cyano esters and ω-formyl α,β-unsaturated nitriles. However, photochemical reactions of 2-(phenylthio)- and 2-(methylthio)cyclohexanones in methanol did not give the corresponding ω-phenylthio or ω-methylthio carboxylic acid esters, products resulting from a preferential cleavage of a carbon-sulfur bond being obtained.
  • Shin-ichi Kamiyama, Toshishige M. Suzuki, Tetsuo Kimura, Akira Kasahar ...
    1978 Volume 51 Issue 3 Pages 909-912
    Published: 1978
    Released: April 19, 2006
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    [3]- and [4]ruthenocenophanes as well as other ruthenocene derivatives were synthesized. The preparation of ruthenocenes in this experiment required more forced reaction conditions than those of the corresponding ferrocenes. Two cyclopentadienyl rings of these ruthenocenophanes are found to tilt mutually, and the degree of the ring-tilting of [3]ruthenocenophane is greater than that of the [4] homolog.
  • Kiyonori Shinoda
    1978 Volume 51 Issue 3 Pages 913-915
    Published: 1978
    Released: April 19, 2006
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    The competitive chlorination of various vinyl compounds was carried out in order to elucidate the effect of the structure on the addition rate of chlorine to a double bond. A linear free-energy relationship was found to exist between the reactivities in the presence of oxygen and Taft’s σ* constants. The ρ* value was calculated to be −1.20. On the other hand, the plot deviated slightly from a straight line; this shows the Taft relationship between the reactivities for the photochlorination and σ* values, known as an extra acceleration due to the hyperconjugation of the alkyl group.
  • Kan-ichi Hasegawa, Ryuzo Asami, Kensuke Takahashi
    1978 Volume 51 Issue 3 Pages 916-920
    Published: 1978
    Released: April 19, 2006
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    The chemical shifts of the C1 and C2 of trans-1-alkyl-1,3-butadienes were correlated with Taft’s σ*, the proportionality constants being −35.9 and 12.3 ppm/σ*, respectively. The values 6.2 and −43.6 ppm/σ* were obtained for the C1 and C2 of 2-alkyl-1,3-butadienes, respectively. The observed chemical shifts of disubstituted butadienes roughly agreed with the values estimated from those of monosubstituted butadienes by means of additivity relationship. The cationic reactivity of linear conjugated dienes should be determined by the magnitude of the steric restriction of substituents and that of the stability of the resulting cation.
  • Shinsaku Shiraishi, Satoru Ikeuchi, Manabu Sen\={o}, Teruzo Asahara
    1978 Volume 51 Issue 3 Pages 921-925
    Published: 1978
    Released: April 19, 2006
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    The reaction of 2,4,6-trimethylbenzonitrile N-oxide with various di- and tetrasubstituted p-benzoquinones and the structures of the products were studied. All of the tetrasubstituted quinones gave dioxazole derivatives through addition at the carbonyl site, whereas the disubstituted quinones gave dioxazoles or isoxazoline derivatives depending on the substituents. The reactivity of the quinone carbonyl toward the nitrile oxide varies with the substituents and with the substitution pattern; this phenomenon is discussed in terms of the resonance and inductive effects of the substituents.
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