Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 58 , Issue 8
Showing 1-50 articles out of 70 articles from the selected issue
  • Shiro Hatakeyama, Shigeo Honda, Nobuaki Washida, Hajime Akimoto
    1985 Volume 58 Issue 8 Pages 2157-2162
    Published: 1985
    Released: June 27, 2006
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    Rate constants for reactions of OH radicals with four kinds of simple ketenes (ketene, methylketene: MK, ethylketene: EK, and dimethylketene: DMK) were measured in 1 atm of air at 299±2 K by use of a competitive reaction method. The photolysis of CH3ONO in air was used to generate OH radicals. The rate constants for OH reactions obtained are (1.8±0.2)×10−11, (7.6±1.4)×10−11, (11±3)×10−11 and (10±3)×10−11 cm3 molecule−1 s−1 for ketene, MK, EK, and DMK, respectively. The major product was a carbonyl compound; HCHO from ketene, CH3CHO from MK, and CH3COCH3 from DMK; the yield was ≈80%, 72±17%, and 70±3%, respectively. It is proposed that the reaction proceeded mainly via an OH addition to the olefinic carbons of ketenes and the adduct decomposes to give a carbonyl compound and CO as final products in air.
  • Tomoaki Shimoda, Toshio Okuhara, Makoto Misono
    1985 Volume 58 Issue 8 Pages 2163-2171
    Published: 1985
    Released: June 27, 2006
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    Several vanadium–phosphorus mixed oxides with a P/V ratio=1 have been prepared and the relationships between the structure of catalyst and the catalytic function for the selective oxidation of butane to maleic anhydride were examined. As revealed from XRD, IR, XPS, and redox titration studies, five among them were presumably composed of crystalline single phases, that is, α-VOPO4, β-VOPO4, and (VO)2P2O7 as well as unknown phases X1 and X2. The valences of the vanadium of these catalysts were close to five, except for (VO)2P2O7 (the valence was four). These phases were prepared, respectively, by controlling the kind of precursors and the calcination conditions. The selectivity to maleic anhydride differed markedly among these catalysts, although the rate did not change much when it was normalized to surface area. The selectivity at 440 °C was less than 20% for α- and β-VOPO4, 40% for X1 and X2, and 70% for (VO)2P2O7. Amorphous phases having V4+ were much less selective than (VO)2P2O7. No structural changes of the catalysts after use were observed in the cases of α-, β-VOPO4, and (VO)2P2O7. Therefore, the effective phase for selective oxidation of butane to maleic anhydride was speculated to be a phase like (VO)2P2O7 in which the valence of vanadium is four and the structure is stable under the reaction conditions.
  • Kunihiko Yokoi, Iwao Watanabe, Shigero Ikeda
    1985 Volume 58 Issue 8 Pages 2172-2175
    Published: 1985
    Released: June 27, 2006
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    The kinetics of polarographic catalytic reduction of nitrate and perchlorate by electrogenerated transient species of Mo(V) are investigated in 0.1M sulfuric acid solution. Second-order rate constants for the catalytic reaction with nitrate and perchlorate obtained after Koutecky’s treatment are (2.1±0.4)×103 and (1.9±0.1)×102M−1 s−1, respectively. Stable Mo(V) species in sulfuric acid solution is studied by spectrophotometry. It is concluded that there exists dimer-dimer-monomer equilibria. The oxidation of the monomer with perchlorate in 14M H2SO4 obeys the second-order rate law –d[monomer]/dt=k[monomer][ClO4], where k=(1.59±0.13)×10−1 M−1 s−1. The results indicate that electrogenerated Mo(V) in 0.1M H2SO4 is not the same species as the stable monomeric Mo(V) in 14M H2SO4.
  • Kazuho Inaba, Nobuyuki Itoh, Yumi Matsuno, Tatsuya Sekine
    1985 Volume 58 Issue 8 Pages 2176-2180
    Published: 1985
    Released: June 27, 2006
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    The rate of formation of iron(III) complexes with several β-diketones (HA) in aqueous sodium perchlorate solutions has been determined by a solvent-extraction method. The rate was found to be first order with respect to the reagent, and zero to an inverse second order with respect to the hydrogen-ion. From the results, the controlling step has been determined to be the formation of the first complex in aqueous solutions. Three types of unit reactions are suggested for this; (i) Fe3++HAenol, which has an associative character; (ii) Fe(OH)2++HAenol and; (iii) Fe(OH)2++A, both of which has a dissociative character.
  • Koe Enmanji
    1985 Volume 58 Issue 8 Pages 2181-2184
    Published: 1985
    Released: June 27, 2006
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    Photo- and thermal polymerizations of methyl methacrylate (MMA) in the presence of α-tocopherol were investigated in air or in vacuo. α-Tocopherol at higher concentrations inhibits both the photopolymerization of MMA sensitized by benzoin ethyl ether and the thermal polymerization induced by benzoyl peroxide, but at lower concentrations is able to initiate photopolymerization of MMA under aerobic conditions. Spectral data indicate that a fraction of α-tocopherol is incorporated in the produced polymer chain.
  • Sadatoshi Akabori, Hiroyuki Munegumi, Yoichi Habata, Sadao Sato, Kayok ...
    1985 Volume 58 Issue 8 Pages 2185-2191
    Published: 1985
    Released: June 27, 2006
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    Polyoxa-1,n-dithia[n](1,1′)ruthenocenophanes were prepared by treatment of 1,1′-ruthenocenedithiol with α, ω-dibromo polyethers. The ruthenocenophanes formed efficiently complexes with soft ions, but not with hard and borderline cations. The 1H- and 13C-NMR spectral data of the silver(I) ion-complexed ruthenocenophanes suggested a partial electron-transfer interaction between the ruthenium atom of the ruthenocene nucleus and the incapsulated silver(I) ion. The crystal structure of the 1:1 complex of 4,7,10,13-tetraoxa-1,16-dithia[16](1,1′)ruthenocenophane with mercury(II) chloride was determined by the X-ray method. The crystals are triclinic, space group P\bar1, with a=13.722(3), b=11.678(4), c=8.179(2) Å, α=102.69(3), β=72.82(2), γ=100.73(2)°, Z=2, Dx=2.11 g cm−3. The mercury(II) cation and the two chloride ions are situated in the central cavity of the macrocyclic moiety and at the apexes, respectively. The distance between the ruthenium atom of a ruthenocene nucleus and the incapsulated mercury(II) ion is 4.846 (2) Å which is too long for direct metal–metal interaction.
  • Shuzo Akiyama, Hiroyuki Akimoto, Shin’ichi Nakatsuji, Kenichiro ...
    1985 Volume 58 Issue 8 Pages 2192-2197
    Published: 1985
    Released: June 27, 2006
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    A synthesis of fifteen kinds of 2-(4-substituted phenyl)benzofurans (4n) was carried out and their fluorescence spectral properties were investigated concerning their applicability as organic reagents for analyses.
  • Choichiro Shimasaki, Masanori Takeuchi, Junichiro Tsutuguchi, Koichi S ...
    1985 Volume 58 Issue 8 Pages 2197-2202
    Published: 1985
    Released: June 27, 2006
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    Die Pyrolyse von Tris(2,3-epoxypropyl)-1,3,5-triazin-2,4,6(1H,3H,5H)-trion (1)[zwei Razem-Modifikationen: Typus (R,R,R)/(S,S,S) Schmp. 103–104 °C (1a); Typus (R,R,S)/(S,S,R) Schmp. 156–157 °C (1b)] und Tris(2,3-epoxy-3-methylpropyl)-1,3,5-triazin-2,4,6(1H,3H,5H)-trion (2) wurde bei thermischen Analysen untersucht. Der Spaltungsmechanismus durch Elektronenschlag von 1 und 2 wurde massenspektrometrisch untersucht. Die thermische Zersetzungsreaktion verläuft via die Bildung von 5-gliedrige Ringe (Oxazolidinon Ring) und dem Schmelzzustand. Eine kinetische Rechnung der thermischen Zersetungsreaktion auf Grund von DTA Kurven hat gezeigt, daß die Aktivierungsenergien der Zersetzungsreaktionen von 1a, 1b, und 2 jeweils 114,170, und 146 kJ mol−1 sind. Der Hauptspaltungsmechanismus fur der Zersetzung mit dem Elektronenschlag von 1 und 2 besteht aus fünf Spaltungsstilen. Der hochauflösende Massenspektrometrie bestätigte die Zusammensetzung einer großen Anzahl von Spitzen in niederauflösenden Massenstrahlenspektren. Mittels der Kernresonanzspektroskopie läßt sich auch Spinentkopplungen und Lösungsmitteleinflüsse bei 1 und 2 untersuchen.
  • Ichiro Hirao, Masahiko Yamaguchi, Takashi Terada, Koichi Hasebe
    1985 Volume 58 Issue 8 Pages 2203-2206
    Published: 1985
    Released: June 27, 2006
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    Treatment of 5- and 7-methoxy-2-methyl-4H-1-benzothiopyran-4-one with lithium diisopropylamide followed by electrophiles gave 2-substituted 4H-1-benzothiopyran-4-ones. Utilizing this reaction, 3-substituted 6- and 8-methoxy-1,2-dihydrocyclopenta[b][1]benzothiopyran-9(3H)-ones were also synthesized, and several compounds showed potential analgesic and anti-inflammatory activities.
  • Takeshi Komai, Kazuo Matsuyama
    1985 Volume 58 Issue 8 Pages 2207-2211
    Published: 1985
    Released: June 27, 2006
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    Di-t-butyl peroxydicarbonate(DBPD) has been synthesized in a novel route and thermally decomposed at 40–70 °C. The decomposition exhibits first-order kinetics and the values of ΔH\ eweq and ΔS\ eweq are 122 kJ mol−1 and 46 J K−1 mol−1, respectively. 2-Methyl-2-propanol is obtained quantitatively as a decomposition product and the rates are a little dependant on the viscosities of solvents, normal alkanes. The mechanism that involves the initial scission of the O–O bond is discussed and the values of the rates and the activation parameters of DBPD are compared with those of diacetyl peroxide and dibenzoyl peroxide.
  • Jiro Toyoda, Toshikazu Ibata, Hatsue Tamura, Kazuhide Ogawa, Tsuyoshi ...
    1985 Volume 58 Issue 8 Pages 2212-2216
    Published: 1985
    Released: June 27, 2006
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    The Cu(acac)2-catalyzed decomposition of o-methoxycarbonyl-α-diazoacetophenone in the presence of acenaphthylene gave a 2:1-cycloadduct of the corresponding carbonyl ylide, 1-methoxy-2-benzopyrylium-4-olate, with acenaphthylene along with exo- and endo-1:1-adducts. The molecular structure of the 2:1-adduct was determined by means of X-ray analysis. The colorless crystals of the adduct are triclinic with the space group P\bar1,and with the unit-cell dimensions of a=12.104(2), b=12.477(3), c=9.112(2)Å, α=102.98(3), β=110.16(2), γ=70.65(1)°, and Z=2. The structure was determined by direct methods and refined by block-diagonal least-squares methods. All hydrogen atoms were revealed by a difference-Fourier synthesis, and further least-squares refinement gave the final R value of 0.057 for 3681 observed reflections. The configurations of methine protons obtained by X-ray methods are compatible with the NMR coupling pattern of the adduct.
  • Yoshihisa Inoue, Kazuyoshi Goan, Tadao Hakushi
    1985 Volume 58 Issue 8 Pages 2217-2220
    Published: 1985
    Released: June 27, 2006
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    The direct photolyses at 185 nm of some naturally occurring and related bichromophoric alkenes possessing hydroxyl or methoxycarbonyl group at an allylic, homoallylic, or remote position gave the geometrical isomers as the major photoproducts detectable on gas chromatography. The isomerization yield was highly sensitive to the functional group introduced and its position; allylic alkenols gave poor yields, while both functionalization at a remote position and esterification of the hydroxyl group improve the photoisomerization yield.
  • Fumio Toda, Koichi Tanaka, Thomas C. W. Mak
    1985 Volume 58 Issue 8 Pages 2221-2227
    Published: 1985
    Released: June 27, 2006
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    The structures of a 1:2 molecular complex(I) of 1,1,6,6-tetrakis(2,4-dimethylphenyl)-2,4-hexadiyne-1,6-diol with ethanol, a 1:1 complex(II) of 1,1-bis(2,4-dimethylphenyl)-2-butyn-1-ol with ethanol, and a 1:1 complex(III) of 9-hydroxy-9-(1-propynyl)fluorene with methanol have been determined by X-ray crystallography. The crystal data are: I, C42H50O4, P\bar1, a=8.249(3), b=9.522(5), c=14.803(8)Å, α=100.95(4), β=110.82(4), γ=113.08(3)°, Z=1, and Rf=0.105 for 1834 observed Mo Kα data; II, C22H28O2, P\bar1, a=8.142(2), b=11.281(3), c=l2.262(4)Å, α=102.76(2), β=97.08(2), γ=111.19(2)°, Z=2, and Rf=0.073 for 2104 data; III, C17H16O2, P21/a, a=8.641(5), b=10.883(5), c=30.63(2)Å, β=92.88(4)°, Z=8, Rf=0.154 for 1885 data. The crystal structures of I and II are closely related and both feature planar hydrogen-bonded (OH)4 rings centered at centrosymmetric sites. In III, the fluorene and methanol molecules belong to two independent sets, and the molecular components in each set are alternately linked by hydrogen bonds to form infinite zigzag chains parallel to the a axis.
  • Yasushi Inoue, Osamu Tochiyama
    1985 Volume 58 Issue 8 Pages 2228-2233
    Published: 1985
    Released: June 27, 2006
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    The formation constants of the complexes of Np(V) with fluoride, sulfate, and phosphate have been determined in 1 mol dm−3 NaClO4 at 25 °C by means of the solvent-extraction method using 2-thenoyltrifluoroacetone and 1,10-phenanthroline. Extractions at various pH values revealed that H2PO4 and HPO42− participate in the complex formation of Np(V).
  • Shinkichi Yamada, Motoharu Tanaka
    1985 Volume 58 Issue 8 Pages 2234-2238
    Published: 1985
    Released: June 27, 2006
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    The formation rate of some anionogallium(III) complexes (GaA) with 4,5-dihydroxy-1,3-benzenedisulfonate (H2L2−) in the presence of thiocyanate ion has been studied spectrophotometrically by a stopped-flow technique. The rate law is expressed as d[GaL]/dt=kGa[Ga3+[H2L2−]+kGaOH[GaOH2+][H2L2−]+kGa(OH)2[Ga(OH)2+][H2L2−]+kGaNCS[GaNCS2+][H2L2−], with kGa=101.23 M−1 s−1 (M=mol dm−3), kGaOH=103.36 M−1 s−1, kGa(OH)2=104.37 M−1 s−1, and kGaNCS=103.90 M−1 s−1 at 25 °C and I=0.50M. The enhanced reactivity of GaA as compared to that of Ga3+ is attributable to the labilizing effect of the bound ligand A on the rate of loss of coordinated water molecules at GaA. Together with the additional formation rate constants of monoisothiocyanato- and monooxalatogallium(III) with 2-hydroxy-2,4,6-cycloheptatrien-1-one, this labilizing effect is quantitatively discussed in terms of the electron-donating ability of the ligand.
  • Katsuhiko Miyoshi, Yukio Sakamoto, Atsuko Ohguni, Hayami Yoneda
    1985 Volume 58 Issue 8 Pages 2239-2246
    Published: 1985
    Released: June 27, 2006
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    Chromatographic resolution of some anion complexes, [Co(ox)2(en)], C1- and C2-cis(N)-[Co(ox)(gly)2], [Co(ox)2(gly)]2−, and [Co(ox)2(acac)]2− (ox=oxalate ion, en=ethylenediamine, gly=glycinate ion, and acac=acetylacetonate ion), was attempted on an ion-exchange column using as chiral selectors several optically active cation complexes such as [Co(en)3]3+, [Co(sep)]3+, [Co(pn)3]3+, [Co(chxn)3]3+, [Co(acac)(en)2]2+, and [Co(gly)(en)2]2+ (sep=1,3,6,8,10,13,16,19-octaazabicyclo[6.6.6]icosane, pn=propylenediamine, and chxn=trans-1,2-cyclohexanediamine). The elution orders and degrees of optical resolution attained were interpreted on the basis that chiral discrimination is effected along either the C3 (or pseudo C3) axis or the C2 (or pseudo C2) axis of the respective complexes; the cation complex faces the anion complex with its N–H protons hydrogen-bonded to the coordinated oxygen atoms of the anion complex along the (pseudo) C3 or C2 axis. Plausible association models were proposed, which indicate that homochiral (i.e., Δ-Δ or Λ-Λ) and heterochiral (i.e., Δ-Λ or Λ-Δ) combinations are favored when the cation complex directs its C3 and C2 axes to the anion complex, respectively, regardless of which axis (C3 or C2) of the anion complex is directed to the cation complex. Most of the experimental data are consistently explained within the framework of the association models proposed.
  • Masakazu Takata, Kazuo Kashiwabara, Haruko Ito, Tasuku Ito, Junnosuke ...
    1985 Volume 58 Issue 8 Pages 2247-2254
    Published: 1985
    Released: June 27, 2006
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    Nine new cobalt(III) complexes of the types, [Co(acac)(L)(edpp)]2+ (L=ethylenediamine(en), (1R,2R)-1,2-cyclohexanediamine(RR-chxn), 2,2′-bipyridyl(bpy)), [Co(acac)(L′)(empp)]2+ (L′=en, bpy), and structurally related [Co(acac)(bpy)(en)]2+ were prepared and resolved into optical isomers, where acac, edpp, and empp denote an acetylacetonate ion, (2-aminoethyl)diphenylphosphine, and (2-aminoethyl)methylphenylphosphine, respectively. The molecular structure of (+)531CD-[Co(acac)(RR-chxn)(edpp)](ClO4)2 was determined by single-crystal X-ray analysis. Crystal data; monoclinic, P21, a=19.562(3)Å, b=16.882(1)Å, c=9.696(1)Å, β=91.22(1)°, V=3201.3(6)Å3, Z=4. Three nitrogen donor atoms in the complex ion are arranged in the facial mannar (fac(N)) and the absolute configuration of the complex ion is Λ. The structures of other complexes were assigned by comparing the 1H NMR and circular dichroism spectra with those of the fac(N)-Λ-[Co(acac)(RR-chxn)(edpp)]2+ complex. The complexes containing a 1,2-diamine yielded selectively the fac(N) isomer, whereas those containing bpy the mer(N) isomer.
  • Tetsuaki Nishida, Toshiaki Nonaka, Yoshimasa Takashima
    1985 Volume 58 Issue 8 Pages 2255-2259
    Published: 1985
    Released: June 27, 2006
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    Structural studies on the ternary BaF2–ZrF4–FeF2 glasses have been performed to elucidate the local structure of the ZrF4-based glasses which are known to be excellent in the optical transparency and the electric conductivity due to F ion. Mössbauer and Raman measurements reveal that iron (Fe2+ and Fe3+) plays a structural role similar to that of Ba2+ ion surrounded by eight fluorine atoms at the interstitial site of one- or two-dimensional zigzag chains composed of ZrF6 octahedra. Raman and DTA measurements reveal that the increase in the fraction of BaF2 causes an increase in the coordination number of Zr from 6 to 7. Mössbauer measurements of 25BaF2·65ZrF4·10FeF2 glass at lower temperatures lead to a conclusion that the glass undergoes a phase transition at 225±5K, of which structural change is easily reflected in the isomer shift, quadrupole splitting, and the absorption area. This is supported by the DTA measurement of the same sample at lower temperatures, i.e., the DTA curve consists of two exothermic peaks and a wide endothermic peak observed at about 220–230 K and 180–210 K, respectively.
  • Yoshito Takaki, Hiroshi Yamaguchi, Kazuaki Nakata
    1985 Volume 58 Issue 8 Pages 2260-2262
    Published: 1985
    Released: June 27, 2006
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    A method for predicting possible preferred orientation planes in organic and inorganic powders of known crystal structures is presented. The usefulness of this method is demonstrated by applying it to the powders of benzamide, the α-form of 2-pyrazinecarboxamide, benzoic acid, olivine, and the high-temperature form of Li3PO4. It should be noted that the existence of preferred orientation axes found in the powders of benzoic acid and Li3PO4 can be well explained in terms of zone axes, each formed by two sets of cleavage planes.
  • Yoshiya Kera, Tadashi Oonishi, Hisateru Imori, Shigeharu Kida
    1985 Volume 58 Issue 8 Pages 2263-2267
    Published: 1985
    Released: June 27, 2006
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    The electric property of a pure VO2 thin films, prepared from a vanadium naphthenate by thermal decomposition, was examined preliminarily under various inorganic gas atmospheres, H2O, H2, O2, N2O, and NO2, at 20–200 °C. Only in the case of the H2O adsorption, did the conductivity-temperature curve change reversibly; in the other cases it changed irreversibly. With respect to the VO2 films doped with Na2O, ZrO2, Cr2O3, and TiO2, similarly, the conductivities changed reversibly with the water vapor adsorbed; the extent and the manner of these changes differed rather greatly depending upon the kind of metal oxides doped. In the Zr–VO2 film, which had a large conductivity (σ) and its gap (Δσ) at the transition point (Tt=60 °C) relative to the pure VO2 film, the electric property was almost unaffected by water–vapor adsorption. In the cases of the Cr– and Ti–VO2 films, with quite small σ and Δσ values relative to the pure VO2 film, on the contrary, the In σ–1/T curves decreased parallelly to less than about one-half of that under a vacuum throughout the temperature range. With the Na–VO2 film, the σ–1/T curve measured under water vapor gradually nears that under a vaccum with the elevation of the temperature to 200 °C. From the comparisons of the effects of the electric properties of these doped films on the water vapor adsorbed, the structural features of the films, especially the contact states in the boundary layer, were deduced favorably. Furthermore, a possibility of the application to a switching element working at about 60 °C was suggested for the Zr–VO2 film, and that to a fume sensor working at a temperature less than 200 °C, for the Cr– and Ti–VO2 films.
  • Toshihiko Kimura, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1985 Volume 58 Issue 8 Pages 2268-2271
    Published: 1985
    Released: June 27, 2006
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    N-Ethylcarbazole crystallizes in the orthorhombic system, space group Pbca with fairly large unit cell dimensions of a=7.971(1), b=24.615(3), c=56.587(5) Å, Dm=1.17 g cm−3, Dc=1.168 g cm−3 for Z=40. The structure was solved by the direct method and refined anisotropically by the least-squares procedure, R=0.062 for 5134 non-zero reflections. Five crystallographically independent molecules are not different from each other, the carbazole group is planar, and the ethyl group attached to the nitrogen atom is almost perpendicular to the carbazole ring. In the crystal, each carbazole ring makes a similar angle with the a axis [52 to 55°].
  • Chuji Katayama, Masako Honda, Hiroaki Kumagai, Jiro Tanaka, Gunzi Sait ...
    1985 Volume 58 Issue 8 Pages 2272-2278
    Published: 1985
    Released: June 27, 2006
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    Hexacyanobutadiene(HCBD) forms two kinds of molecular complexes with tetramethyltetrathiafulvalene(TMTTF) one kind with tetramethylthiotetrathiafulvalene(TTMTTF). The crystal structures of these complexes and neutral TTMTTF are determined by X-ray analyses. (TMTTF)2·HCBD is composed of 2:1 donor and acceptor, and TMTTF exists as a dimer cation stacked along the c axis. HCBD anions are included in the cavity of the dimer stack directing their molecular planes parallel to the stacking axis. TMTTF·HCBD is composed of 1:1 donor and acceptor, and has segregated cation and anion stacks with the interplanar spacing of 3.61 Å in TMTTF and 3.43 Å in HCBD columns. TTMTTF·HCBD is shown to have a regular segregated column with a partial charge transfer. Neutral TTMTTF has a non-planar conformation. The C=C and C–S bond lengths of the donors in free and complexed states are correlated with the degree of the charge transfer in these four complexes, and linear relationships are found between these two quantities.
  • Shamim Akhtar, Jiro Tanaka, Kazuhiro Nakasuji, Ichiro Murata
    1985 Volume 58 Issue 8 Pages 2279-2284
    Published: 1985
    Released: June 27, 2006
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    Experimental results of the polarized reflection spectra and the calculated absorption spectra of 3,4:3′,4′-bis(tetramethylene)-2,2′,5,5′-tetrathiafulvalene (OMTTF)–TCNQ and OMTTF–1,4-dihydro-1,4-bis(dicyanomethylene)triptycene(DBTCNQ) crystals are discussed by developing approximate theoretical models, based on the CT mechanism. The electronic structures conform well that, OMTTF–TCNQ is a neutral crystal whereas, OMTTF–DBTCNQ is ionic. Furthermore, the temperature dependent spin susceptibilities imply the former as diamagnetic and the latter as a regular Heisenberg antiferromagnet.
  • Hideaki Fujiwara, Naoto Shimizu, Tatsuya Takagi, Yoshio Sasaki
    1985 Volume 58 Issue 8 Pages 2285-2288
    Published: 1985
    Released: June 27, 2006
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    NMR spectra of the titled compounds (α- and β-BHC) have been measured in nematic solvents and analyzed. Vibrational corrections were important for the full interpretation of the observed direct couplings. The order parameters showed that the BHC molecules orient most preferably with their six-membered rings parallel to the optic axis of the nematic solvents. Molecular structure of α-BHC derived from the direct couplings corresponds well with those determined by the X-ray method on a crystal and calculated by the MNDO MO method. For β-BHC, however, discrepancies are found with the crystallographic structure, suggesting molecular deformations in the crystal state. Principal axes have been determined for the order matrix and compared with those for the moment of inertia. The difference between the two principal axis systems in α-BHC is interpreted as due to a steric repulsive effect between the two axial chlorine atoms and the solvent molecules.
  • Hiroyasu Iwahara, Hiroyuki Uchida, Satoshi Mizoguchi
    1985 Volume 58 Issue 8 Pages 2289-2293
    Published: 1985
    Released: June 27, 2006
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    A new carbide method based on “Manganese Cycle” was studied in order to produce new fuel gas. This process consists of four steps; (i) carbide production from Mn2O3 and solid carbon sources, (ii) fuel gas production by means of hydrolysis of the carbide, (iii) spontaneous oxidation of Mn(OH)2 with air to Mn2O3, and (iv) regeneration of the carbide from Mn2O3 and new carbon sources. In this process, manganese is used as a recyclable medium for gas production, and hydrogen and hydrocarbons (C1–C5) are obtained by hydrolysis. Carbon monoxide generated during the formation of the carbide is also utilizable. The addition of Li2CO3 was effective for the carbide reproduction.
  • Kazuyori Konishi, Hiroshi Matsumoto, Katsuhiro Saito, Kensuke Takahash ...
    1985 Volume 58 Issue 8 Pages 2294-2297
    Published: 1985
    Released: June 27, 2006
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    The 1H and 13C NMR spectra have been observed for the anions, produced from methyl-, ethyl-, and isopropylpyridines, in tetrahydrofuran (THF). Two kinds of anions are formed concomitantly by lithium-proton exchange and addition of butyllithium from 2-ethyl-, 2-isopropyl-, 4-methyl-, and 4-ethylpyridines. The former reaction tends to occur at the substituent bonded to the position adjacent to nitrogen, and the latter one occurs at the position adjacent to nitrogen without substituent. In the anions formed by the exchange from 2- and 4-ethylpyridines, a specific ring proton is coupled to the α-carbon, and, further, the ortho- or meta- protons (or -carbons) in the latter anion are nonequivalent respectively at room temperature. The α-carbons in these anions are virtually sp2-hybridized.
  • Hiroshi Matsui, Takeo Hisano
    1985 Volume 58 Issue 8 Pages 2298-2303
    Published: 1985
    Released: June 27, 2006
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    The rates of the methanol oxidation and the COad formation at Pt electrodes in solutions of CH3OH+0.5 mol dm−3 H2SO4 were investigated under the conditions minimizing the harmful effect of impurities. Under the particular conditions, the both rates decreased remarkably towards zero at a limiting coverage of about 0.8. Namely, the COad hindered both the formation of the COad itself and the oxidation of methanol via some unidentified intermediate other than COad. This fact was explained by assuming an aggregate with two vacant sites indispensable for the COad formation and the methanol oxidation to CO2.
  • Takashi Yamane, Hiroto Nanayama, Tamaichi Ashida, Kazuhiko Hashimoto, ...
    1985 Volume 58 Issue 8 Pages 2304-2306
    Published: 1985
    Released: June 27, 2006
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    The structure of the dimerization product of bicyclic oxalactam, 8-oxa-6-azabicyclo[3.2.1] octan-7-one, was determined by the X-ray diffraction method. The final R value was 0.062 for 2009 reflections. The structure suggests that the cationic oligomerization of the bicyclic oxalactam proceeds through the C5–N6 scission, differing from the cases of other common lactams.
  • Sukeya Kodama, Masaaki Yabuta, Masakazu Anpo, Yutaka Kubokawa
    1985 Volume 58 Issue 8 Pages 2307-2310
    Published: 1985
    Released: June 27, 2006
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    It has been found with ZnO as well as TiO2 that 2-butene is much more reactive than 1-butene for their photocatalytic isomerization. Although both cis-trans and double bond isomerizations take place on ZnO, only cis-trans isomerization occurs over SnO2. The photocatalytic isomerizations were suppressed drastically in the presence of NO. From those results together with the ESR studies the following conclusions emerge: a butene molecule interacts with the photoformed O to form a radical species as a result of fission of the C=C bond; the photocatalytic isomerization proceeds via such a radical intermediate; the lack of the reactivity of 1-butene appears to be explicable on such basis.
  • Akiyoshi Matsuzaki
    1985 Volume 58 Issue 8 Pages 2311-2317
    Published: 1985
    Released: June 27, 2006
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    The polarization of the light scattered by aerosol has been studied by the theoretical calculation based on the Mie scattering theory. The present calculation obtains the polarization of the light scattered by aerosol as a function of size parameter, i.e. x=2πr⁄λ, where r and λ are the radius of aerosol and the wavelength of the scattered light, respectively, for various refractive indexes. These results give the useful informations for the experimental study on the size-growth in aerosol formation by the measurement of the scattered light polarization. The characteristic of the scattered light intensity, which is usually used as a kind of concentration parameter in the study on aerosol formation, is also discussed.
  • Hiromitsu Terao, Hiroshi Sakai, Hisao Negita
    1985 Volume 58 Issue 8 Pages 2318-2322
    Published: 1985
    Released: June 27, 2006
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    The 127I NQR spectra of 1,4-dithiane–2I2, thiane–I2, 1,4-thioxane–I2, and 1,3,5-trithiane–I2 are reported. Two distinct iodine atoms are observed in the former three complexes, whereas only one iodine atom is present in the last-named complex. The charge densities on the donors and the iodine atoms are obtained according to the Townes-Dailey approximation. The order of donor strength toward the iodine molecule is: thiane>1,4-thioxane>1,4-dithiane>>1,3,5-trithiane. The thioethers can compete with amines in terms of the donor strength to iodine molecules. The no-bond ionic structure of the ground state is less important in the thioether–iodine complexes than in amine–iodine complexes. The positive temperature coefficients found previously in a few similar complexes of amines are observed for the terminal iodine atoms of 1,4-dithiane–2I2, thiane–I2, and 1,4-thioxane–I2. This phenomenon is ascribed to the increasing shift of the dative structure to the no-bond covalent structure with the rise in the temperature.
  • Naoyuki Ito, Tetsuo Saji, Shigeru Aoyagui
    1985 Volume 58 Issue 8 Pages 2323-2326
    Published: 1985
    Released: June 27, 2006
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    Cyclic voltammograms for the reduction of Pd0 and Pt0 complexes with mixed ligands of diimine and olefin exhibit, respectively, two or four reversible one-electron steps. The half-wave potentials of each step give a straight line with a slope of 1.0, when plotted against the half-wave potentials of diimine ligands, and a slope smaller than 0.2, when plotted aganist the half-wave potentials of olefinic ligands. The half-wave potentials of the complexes are affected only a little by the difference in the central metal. These findings lead to the conclusion that each LUMO of these complexes is dominated by the diimine π*-orbital, though it is higherlying than the olefinic π*-orbital in free ligands.
  • Kouzou Yoshitani
    1985 Volume 58 Issue 8 Pages 2327-2330
    Published: 1985
    Released: June 27, 2006
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    The Viscosities and molal volumes of t-butyl alcohol (t-BuOH) in aqueous solutions of [Fe(phen)3]Cl2, [Co(phen)3]Cl3 (phen=1,10-phenanthroline), [Co(en)3]Cl3 (en=ethylenediamine), tetraphenylphosphonium chloride ((C6H5)4PCl), tetramethylammonium chloride (Me4NCl), tetraethylammonium chloride (Et4NCl), and tetra-n-butylammonium bromide ((n-Bu)4NBr) were measured at 25 °C, and solute–solvent interactions characteristic of the metal chelate cations were investigated. The apparent molal volumes of t-BuOH in the solutions of [Fe(phen)3]2+ are larger than those in the (n-Bu)4N+ and [Co(phen)3]3+ solutions. The hydrophobicity of [Fe(phen)3]2+ is not so strong because of the aromaticity of the ligand. The same can be said for [Co(phen)3]3+. However, on the interaction between [Co(phen)3]3+ and t-BuOH, the charge-dipole interaction and hydrophobic interaction act cooperatively to stabilize this pair through the overlap of the solvation spheres.
  • Hideaki Fujiwara, Fumihiko Sakai, Akio Kawamura, Naoto Shimizu, Yoshio ...
    1985 Volume 58 Issue 8 Pages 2331-2335
    Published: 1985
    Released: June 27, 2006
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    Calorimetric titration data have been analyzed to determine thermodynamic parameters of the interacting system. The system studied is MeSnCl3 plus dialkyl sulfoxide in CH2Cl2 and a nonlinear least squares method is utilized to simulate the titration curve. The 1:1 and 1(acid):2(base) complexes are found to coexist in solution, and the effect of alkyl chain length on the complex formation is examined. The complex formation proceeds most favorably under the total carbon number of four, and inductive and steric effects are considered to operate in a compensating way. Entropy changes on the reactions are discussed with the aid of molecular theory of thermodynamic functions, and a new method is suggested that affords the number of solvent molecules released on the complex formation.
  • Masahiro Yamashita, Ichiro Murase, Tasuku Ito, Yoshiki Wada, Tadaoki M ...
    1985 Volume 58 Issue 8 Pages 2336-2339
    Published: 1985
    Released: June 27, 2006
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    The X-ray photoelectron spectra have been measured for the one-dimensional halogen-bridged metal-alternated mixed-valence complexes, [PdII(en)2][PtIVX2(en)2](ClO4)4 (X=Cl, Br, and I) and [NiII(en)2][PtIVX2(en)2](ClO4)4(X=Cl and Br), along with their parent complexes, [Pd(en)2]Cl2, Ni(en)2Cl2, and [PtCl2(en)2]Cl2. As the bridging halogen changes from Cl to I, the binding energies of the Pt(IV)4f levels become lower while those of M(II) (M=Pd and Ni) levels become higher, each gradually approaching to the M(III) binding energies (M=Pt, Pd, or Ni), respectively. Comparing the binding energies of the Pt(IV)4f levels in these hetero-metal mixedvalence complexes with those previously reported for the homo-metal halogen-bridged Pt(II)–Pt(IV) mixedvalence complexes having the same bridging halogens, the reductive trend of the oxidation states of Pt(IV) is found to be significantly suppressed by the metal alternation. In accord with this result, the activation energies obtained from the electrical conductivities are fairly larger than those of the homo-metal Pt(II)–Pt(IV) mixed-valence complexes. Their magnitudes are in the order of PdII–PtIV>NiII–PtIV>PtII–PtIV, suggesting that the electron–electron repulsion energy on M(II) ions plays an important role in mixed-valence states.
  • Seiji Shinkai, Shinichiro Nakamura, Mikio Nakashima, Osamu Manabe, Mas ...
    1985 Volume 58 Issue 8 Pages 2340-2347
    Published: 1985
    Released: June 27, 2006
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    New photoresponsive complexones bearing two iminodiacetic acid units or ethylenediamine units at the two sides of an azobenzene through CH2 or (CH2)2 (AzoIDA(n=1,2) and AzoED(n=1,2), respectively) have been synthesized. The CH2 and (CH2)2 spacers were selected in order to examine the influence of the spacer length on the intramolecular cooperativity for the two ligands in the cis-isomers to coordinate to one metal ion. The thermal cis-to-trans isomerization of AzoIDA was efficiently suppressed by Zn(II) and Cu(II) while that of AzoED was suppressed only by Cu(II). The rate suppression supports the formation of the intramolecular chelate complexes with the metal ion. The measurements of ESR spectra of the cis-isomer·Cu(II) complexes indicated that the square-planar structure of the complexes is somewhat distorted and probably close to a lozenge. The stability constants (Ks) were determined by a displacement method. The Ks values for the cis-isomers were generally greater than those for the trans-isomers, and the Ks for n=2 series increased more clearly. In particular, the Ks for cis-AzoED(n=2)+Cu(II) was improved by 43.8 fold. The photoresponsive change in the stability constants suggests a possible application of the present system as light-driven ion pumps for heavy metal ions.
  • Toshihiro Toyoda, Nobutami Kasai, Soichi Misumi
    1985 Volume 58 Issue 8 Pages 2348-2356
    Published: 1985
    Released: June 27, 2006
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    Molecular structure of syn-[2.2](1,4)anthracenophane (1) and its photoisomer (2) have been determined by means of X-ray diffraction; 1, monoclinic, space group A2, a=25.539(2), b=8.152(1), c=20.561(3) Å, β=106.03(1)° (−149°C), Z=8; 2, monoclinic, space group P21/c, a=8.065(6), b=12.963(9), c=19.580(5) Å, β=91.46(5)°, Z=4. The structure of 1 was solved by the vector search method and 2 by the direct method. Both structures were refined including all hydrogen atoms by the block-diagonal least-squares procedure: R=0.053 and 0.043 for 4413 and 2003 observed reflections for 1 and 2, respectively. Two anthracene nuclei, connected by ethylene bridges at the 1 and 4 positions, in each of the two independent molecules (A and B) of 1 are approximately parallel. However, their overlappings differ slightly. In the photoisomer 2 the two anthracene nuclei are bound by newly formed bonds at the 9 and 10 positions: bond distances are 1.628(5) and 1.637(5) Å whereas the corresponding nonbonded distance in 1 are 3.312(6) and 3.301(6) Å (A molecule) and 3.357(6) and 3.366(6) Å (B molecule).
  • Masami Ishibashi, Takahiko Tsuyuki, Takeyoshi Takahashi
    1985 Volume 58 Issue 8 Pages 2357-2360
    Published: 1985
    Released: June 27, 2006
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    Ailanthone was converted into shinjulactone C with a hexacyclic 1α,12α:5α,13α-dicyclo-9βH-picrasane skeleton. The key reaction consists of an intramolecular ionic [4+2] cycloaddition between a pentadienyl cation and an olefin.
  • Kenji Uneyama, Yosinori Masatsugu, Sigeru Torii
    1985 Volume 58 Issue 8 Pages 2361-2365
    Published: 1985
    Released: June 27, 2006
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    Electrooxidative carbon–carbon bond cleavage is useful for the preparation of 3-methyl-4-oxo-2-phenyl-4H-1-benzopyran-8-carboxylic acid (1b) from 3-methyl-2-phenyl-8-(1-propenyl)-4H-1-benzopyran-4-one (2). Olefin 2 was transformed into 3-methyl-8-(1,2-epoxypropyl)-3-methyl-2-phenyl-4H-1-benzopyran-4-one (3) by the electrochemical bromohydrination in an MeCN–H2O–H2SO4–NaBr–(Pt) system followed by treatment of aqueous sodium hydroxide (94%). The epoxide 3 was electrooxidized in an MeOH–H2SO4–(C) system, affording 8-formyl-3-methyl-2-phenyl-4H-1-benzopyran-4-one (4) in 83% yield. Hydrogen peroxide oxidation of 4 in refluxing 2-butanone gave 1b in 86% yield.
  • Takeo Sato, Kozaburo Nishiyama, Akira Morita, Yoichi Iitaka
    1985 Volume 58 Issue 8 Pages 2366-2369
    Published: 1985
    Released: June 27, 2006
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    The treatment of [2.2]metacyclophanes with aluminum chloride gave a variety of hydropyrenes as the results of dehydrogenation, cycloisomerization, and disproportionation reactions. With ethylaluminum dichloride, however, a highly selective reaction occurred to give trans-trans-1,2,3,3a,4,5,9,10,10a,10b-decahydropyrene. Revised structures were presented for cis-cis- and trans-trans-decahydropyrenes based on 13C NMR and X-ray crystallographic analyses.
  • Mikio Nakamura, Yoshio Suzuki, Michinori Oki
    1985 Volume 58 Issue 8 Pages 2370-2375
    Published: 1985
    Released: June 27, 2006
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    The title compounds of which substituents carry atoms with lone-pair electrons have been prepared and their rotamers isolated as stable entities at room temperature. Deprotonation rates of these rotamers with butyllithium in benzene–hexane solution show a striking difference depending upon the substituents and the rotamers. In both sp and ap series, compounds with a methoxyl group exhibit the largest rate constants, while those with a sulfur substituent show the smallest reactivity. The difference is explained in terms of coordination ability of the heteroatoms toward butyllithium and by taking advantage of the entropy effect at the transition state of lithiation. The difference in reactivities between rotamers is further striking in a sense that the reactions differ in the order; sp rotamers show the first-order kinetics while ap rotamers obey the second-order kinetics in the substrate. By assuming that the observed rates are the sum of the first-order and the second-order contributions, we estimate the minimum ratios of the first-order rate constants between sp and ap rotamers, k1spk1ap, to be >2300 in the methoxyl and dimethylamino derivatives and >240 in the methylthio derivatives.
  • S. K. Srivastava, Satish Kumar, Surendra Kumar
    1985 Volume 58 Issue 8 Pages 2376-2379
    Published: 1985
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A comparative study of permeability for various electrolytes is made on parchment-, polystyrene-, and Araldite based membranes of titanium tungstoarsenate at 20, 25, 30, and 35 °C. At any given temperature the order of permeability increase is K+>Na+>Li+ for 1:1 electrolytes and Ba2+>Ca2+>Mg2+ for 2:1 electrolytes. Permeability values are higher for parchment-based than polystyrene-based membranes. The diffusion of these electrolyte solutions across Araldite based membrane is almost negligible. Thermodynamic parameters of diffusion process, viz., ΔH, ΔS, ΔF have been evaluated at 25 °C by applying the theory of absolute reaction rates. ΔS values are negative for all the cations for both the membranes except that of Li+ which is positive for parchment-based membranes. ΔF values are higher for the polystyrene-based than parchment-based membranes.
  • Syed Ashfaq Nabi, Zia Mahmood Siddiqi, Rifaqat A. K. Rao
    1985 Volume 58 Issue 8 Pages 2380-2384
    Published: 1985
    Released: June 27, 2006
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    Tin(IV) selenophosphate has been synthesized by mixing 0.05 mol dm−3 aqueous solutions of tin(IV) chloride, sodium selenite and sodium dihydrogenphosphate in 1:1:2 ratio at pH=0. The chemical and thermal stabilities are investigated. A tentative formula has been proposed for tin(IV) selenophosphate on the basis of chemical composition, pH titration, IR spectrum and thermogravimetric anslysis. The distribution coefficients of metal ions have been determined in DMF, DMSO, DMF–HNO3, and DMSO–HNO3 media. A number of binary, ternary, and quaternary separations of metal ions have been achieved on the columns of tin(IV) selenophosphate.
  • Hiroshi Noda, Lutz Meinhardt Engelhardt, Jack MacBean Harrowfield, Cha ...
    1985 Volume 58 Issue 8 Pages 2385-2388
    Published: 1985
    Released: June 27, 2006
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    The crystal structure of potassium dithizonate, K+[C6H5·NH·N·CS·N:NC6H5], has been determined by single crystal X-ray diffraction methods at 295 K and refined by full matrix least squares to a residual of 0.045 for 1101 independent “observed” reflections. Crystals are orthorhombic, Pbca, a=28.942(9), b=13.247(4), c=7.163(3)Å, Z=8. The structure determination is the first carried out on a salt rather than a complex of the anion. The pseudo-planar anion stacks parallel to the ab face of the cell with considerable delocalization evident; as indicated by the above formula, the remaining acidic hydrogen atom is associated with one of the nitrogen atoms.
  • Raj Narain Mehrotra
    1985 Volume 58 Issue 8 Pages 2389-2394
    Published: 1985
    Released: June 27, 2006
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    The outer sphere oxidation of 4-oxopentanoic acid(4-OPA), studied at 50 °C by aquavanadium(V) ion, is H+-catalyzed reaction. The reaction has a first-order dependence on each of [Vv], [4-OPA], and [H+]. The H+ catalysis can not be ascribed to keto\ ightleftarrowsenol equilibrium because of the knowledge that a γ-keto acid is the least enolized amongst keto acids. Hence V(OH)32+ (aq) ion is the active oxidant. The proposed mechanism, assumed to involve the initial decarboxylation, is supported by the spot test characterization of acetoin as the intermediate oxidation product. Acetoin is further oxidized to two moles of acetic acid which is the final oxidation product. The overall energy of activation(ΔH1=26±3 kJ mol−1) is lower than the normal value(84 kJ mol−1) and therefore the highly negative value of the overall entropy of activation(ΔS1=−268±8 J K−1 mol−1) is considered to be responsible for the observed slowrate of oxidation.
  • Om Prakash Pandey, Soumitra Kumar Sengupta, Satish Chandra Tripathi
    1985 Volume 58 Issue 8 Pages 2395-2398
    Published: 1985
    Released: June 27, 2006
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    The reactions of mono(cyclopentadienyl)titanium(IV) trichloride with three important series of heterocyclic thioketones, viz., triazolinethiones 4-amino-, 4-benzylideneamino-, 4-furfurylideneamino-, and 4-salicylideneamino-5-trifluoromethyl-1,2,4-triazoline-3-thiones, thioxoquinazolones (3-methyl-, 3-phenyl-, and 3-(o-tolyl)-2-thioxo-4-quinazolones), and oxadiazolethiones (5-phenyl-, 5-(p-nitrophenyl), and 5-(p-chlorophenyl)-1,3,4-oxadiazole-2-thiones, have been studied in anhydrous dichloromethane. The reaction products have been characterized on the basis of elemental analyses, electrical conductance, magnetic susceptibility and spectral (electronic, infrared, and 1H NMR) data. Proton NMR spectra indicate that there is rapid rotation of the cyclopentadienyl ring around the metal ring axis on the NMR time scale at 28 °C.
  • Kailash Nath Mehrotra, Indra Sen Singh, Jalpana Roy
    1985 Volume 58 Issue 8 Pages 2399-2402
    Published: 1985
    Released: June 27, 2006
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    The reaction of 2-imino-1,2-diphenylethanone with sodium in ether and subsequent addition of carbon disulfide or ethyl chloroformate resulted in the formation of 3,4,5-trisubstituted 4-oxazoline-2-thiones and 2-ones, respectively. 1,4-Oxazonines and 1,4-oxazocines were also synthesised from the reaction of 2-imino-1,2-diphenylethanone with sodium in THF followed by addition of dihaloalkanes.
  • Urmi Ghosh, Tridibendra Narayan Misra
    1985 Volume 58 Issue 8 Pages 2403-2406
    Published: 1985
    Released: June 27, 2006
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    Raman phonon spectroscopy and electronic absorption and emission spectroscopy have been used to study the mechanism of reaction and the role of electron–phonon coupling in determining the photoreactivity of p-formylcinnamic acid (p-FCA) in the crystalline state. Raman and infrared spectroscopy in the internal vibration region have been used to characterize the reactant p-FCA and the dimeric product t-3,t-4-bis(p-formylphenyl)-ν-1,c-2-cyclobutanedicarboxylic acid. Phonon spectroscopy reveals that the reaction proceeds principally by a heterogeneous mechanism though a homogeneous mechanism in the initial stage of short time domain can not be ruled out. The electronic spectroscopy suggests a strong electron–phonon coupling in the monomer crystal.
  • Teijiro Ichimura, Andrew R. Auty, Anita C. Jones, David Phillips
    1985 Volume 58 Issue 8 Pages 2407-2408
    Published: 1985
    Released: June 27, 2006
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    The measured fluorescence lifetime of the origin of jet-cooled 1-methylnaphthalene is close to that of naphthalene, whereas the corresponding lifetimes of the 2-substituted are longer. The fluorescence lifetime decreased with increasing excitation energy; this can be attributed to an increase in the rate of intersystem crossing with vibrational excitation.
  • Noriko Iwasaki, Rumiko Horiguchi, Yusei Maruyama
    1985 Volume 58 Issue 8 Pages 2409-2410
    Published: 1985
    Released: June 27, 2006
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    An excimer-like fluorescence band at 470 nm was observed for anthracene liquid. A distinct shoulder at 414 nm was recognized in the absorption spectrum of anthracene liquid. These results suggest the existence of dimeric aggregates in this liquid.
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