Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 66 , Issue 12
Showing 1-50 articles out of 59 articles from the selected issue
  • Kuzhunellil Raghavanpillai Sabu, Rugmini Sukumar, Malathy Lalithambika
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3535-3541
    Published: 1993
    Released: August 16, 2006
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    Natural Kaolinitic clays containing transition metals Fe and Ti in their lattice have been examined for their acidic properties and catalytic activity for the alkylation of benzene with benzyl chloride. Calcination of the clays at 550 °C and subsequent acid-activation using 2 M HCl (1 M = 1 mol dm−3) rendered the kaolinite surface highly acidic with very high acid amount. These clays exhibited high catalytic activity and selectivity for the conversion of benzyl chloride to diphenylmethane. Al(III), Fe(II), and Ti(II) ions exsolved from the lattice of kaolinites by acid activation relocate in the interlamellar space and boost the Brønsted acidity of coordinated hydroxo and proposed to initiate the alkylation. In fact kaolinites having structural transition metal, on acid activation exhibited higher acid amount and enhanced catalytic activity than kaolinites devoid of transition metals and recently studied alkylation catalysts such as synthetic TiO2–SiO2–Al2O3 and Fe2O3–SiO2–Al2O3. Natural kaolinitic clays having transition metals in their lattice possess disordered structure and hence on acid activation results in the generation of larger amounts of relocatable cations, higher surface area and higher acidity compared to an ideal kaolinite. Also their acid amount and catalytic activity retained up to five successive regeneration cycles studied.
  • Hiroyuki Noda, Kazuo Oikawa, Hiroaki Ohya-Nishiguchi, Hitoshi Kamada
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3542-3547
    Published: 1993
    Released: August 16, 2006
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    The ESR spin-trapping technique using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and N-t-butylbenzylideneamine N-oxide (PBN) as spin-trap reagents has been applied to detect active oxygen radicals generated by the photoexcitation of powdery semiconductors (TiO2, WO3, CdS, and Fe2O3) in non-aqueous solvents such as dimethylsulfoxide (DMSO), benzene, ethanol, and acetonitrile. Appreciable amounts of superoxide ion (O2) were detected from TiO2, WO3, Fe2O3, and CdS suspensions under photoexcitation. The hyperfine splitting constants (hfsc) of the superoxide ion and carbon(C)-centered radical spin adducts for DMPO and PBN could be determined in various non-aqueous solvents. Some characteristic features for the production of the superoxide ion and C-centered radicals are discussed in connection with the energy-level diagrams of the semiconductors and the redox potentials of the superoxide ion and non-aqueous solvents.
  • Sadamu Yoshida, Kozo Kozawa, Yusei Maruyama, Tokiko Uchida
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3548-3552
    Published: 1993
    Released: August 16, 2006
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    Mobilities of charge carriers in sublimed films of three phenothiazine derivatives, benzo[b]phenothiazine, dibenzo[a,j]phenothiazine, and triphenodithiazine, were measured in surface-type cells at room temperature in both transient and stationary phtoconduction. The drift mobilities in films of these three materials, which are the sum of electron and hole mobilities, are on the order of 10−7—10−5 cm2 V−1 s−1. They do not seem to be affected by the orientation of molecules in the sublimed films.
  • Kazuchika Ohta, Mitsuo Moriya, Mayumi Ikejima, Hiroshi Hasebe, Tetsuya ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3553-3558
    Published: 1993
    Released: August 16, 2006
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    Bis[1,2-bis(3,4-dialkoxyphenyl)ethanedione dioximato]palladium(II) complexes, (abbreviated [Pd{(CnO)4dpg}2]; n = 1—12)have been synthesized and characterized. It was found that each of the [Pd{(CnO)4dpg}2] (n = 2—12) complexes has an enantiotropic discophase (Dhd). The clearing points of the [Pd{(CnO)4dpg}2] (n = 4, 8, 12) complexes are higher than those of the corresponding [Ni{(CnO)4dpg}2] (n = 4, 8, 12) complexes. Interestingly, the [Pd{(CnO)4dpg}2] complexes exhibit thermochromism and solvatochromism similar to that of [Ni{(CnO)4dpg}2] complexes.
  • Kazuchika Ohta, Mitsuo Moriya, Mayumi Ikejima, Hiroshi Hasebe, Tetsuya ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3559-3564
    Published: 1993
    Released: August 16, 2006
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    The bands in the electronic spectra of the [Pd{(C12O)4dpg}2] and [Pd{(C6)4dpg}2] complexes were assigned by using the results of temperature-dependent electronic spectral measurements. The temperature-dependent electronic spectra of “cast samples” of the complexes showed that two characteristic bands shift to higher energy (blue shift) with increasing temperature. The band which is located at a longer wavelength was assigned to the 4dz2–5pz transition (d–p band), and that located at a shorter wavelength to the metal-to-ligand charge-transfer transition (MLCT band). The absorption intensities of both bands strongly depend on the sample film preparation manners and temperatures. From these facts, the mechanism of this unique “mesomorphic thermochromism” has been established.
  • Masahiko Kamada, Hirotaka Nishijima, Yoshiya Kera
    1993 Volume 66 Issue 12 Pages 3565-3570
    Published: 1993
    Released: August 16, 2006
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    Silica gel (SiO2) was modified by a dip-cure method with silane coupling agents having an amine-group: (3-anilinopropyl), (3-aminopropyl), and N-[3-(2-aminoethyl)aminopropyl] trimethoxysilanes. 12-tungstophosphate (PW12) was deposited on the carriers as a test catalyst material. The amounts and the dispersed states of the silane agents and PW12 on the modified SiO2 were successfully analysed by gravimetry as well as UV and FT-IR spectrometries. The amount of PW12 deposited increased in proportion to the amount of the silane agents on SiO2 in the case of deposition under a constant concentration of PW12-solution, although only a little PW12 was deposited directly on SiO2. The acidic site of PW12 was confirmed to interact directly with the amine-group on the modified SiO2, and the strength of the interaction was correlated with the basicity of the amine-group. The activity per gram of catalyst for the dehydration of 2-propanol as a test reaction is generally higher than that on a directly deposited one, although the activity per PW12 unit certainly decreases with the SiO2-modification. The activity was confirmed to increase by a pretreatment at high temperatures, such that the amine-group was completely decomposed. It was clearly shown that the present modification method could be effectively applied for preparing a highly dispersed heteropoly acid catalyst on carriers.
  • Pradyot Kumar Chowdhury
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3571-3575
    Published: 1993
    Released: August 16, 2006
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    IR multiphoton dissociation of Octafluorocyclopentene is used as an efficient means for the generation of :CF2. Time resolved infrared chemiluminescence has been observed from the reaction of ground state :CF2 (X1A1) radicals with molecular oxygen, generating COF2 as a product. IR emission observed around 5 μm region has been assigned to ν1 and 2ν2 modes of COF2. The kinetic measurements of the reaction as a function of oxygen pressure suggest a rate constant to be 5 × 1011 cm3 mol−1 s−1, which corresponds to a :CF2 temperature of ≤3650 K.
  • Ashim Kumar Dutta, Amlan Jyoti Pal, Tridibendra Narayan Misra
    1993 Volume 66 Issue 12 Pages 3576-3580
    Published: 1993
    Released: August 16, 2006
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    Excellent Langmuir–Blodgett (LB) films of 9,10-diphenylanthracene (DPA) and α,α-linked sexithiophene (6T) with arachidic acid (AA) can be formed on water subphase and can be transferred on to quartz substrates. Electronic absorption and emission spectra of these films have been studied and compared with those in solution. Results suggest formation of aggregates of DPA and 6T in LB films. 6T has been used as a quencher for the DPA donor fluorescence. It is shown that the efficiency of energy transfer from the donor to the acceptor decreases with the quadratic power of the distance separating them. Such quadratic dependence confirms that the donor excitation is delocalized.
  • Takashi Kato, Chihiro Jin, Fumiko Kaneuchi, Toshiyuki Uryu
    1993 Volume 66 Issue 12 Pages 3581-3584
    Published: 1993
    Released: August 16, 2006
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    Liquid-crystalline benzoic acid derivatives, 4-pentylbenzoic acid and 4-hexylbenzoic acid, have been examined by infrared spectroscopy. These benzoic acids show nematic phases. In the crystalline state, only the dimeric form is observed. However, the monomeric non-hydrogen-bonded benzoic acid appears once the temperature reaches the crystal-nematic transition (melting) point. The fraction of the monomeric moiety increases upon heating and an abrupt increase is observed at the isotropization temperature. These results suggest that the stability of the hydrogen bonds is not simply a function of the temperature, but greatly depends on the molecular orientation.
  • Haruo Nakayama, Kei Baba
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3585-3588
    Published: 1993
    Released: August 16, 2006
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    In order to confirm the formation of hydrates, both the solid–liquid phase diagrammatic method and the thermal analytic method using a differential scanning calorimeter were applied to binary mixtures of water with various tetraisopentylammonium salts having polyanions, poly(vinyl sulfate) anion and poly(styrenesulfonate) anion, as well as related low molecular-weight anions, ethyl sulfate ion and p-ethylbenzenesulfonate ion. It was found that the two salts with the polyanions and ethanesulfate could form hydrates with large hydration numbers: The melting point and hydration numbers were estimated to be around 16.5 °C and 34 ± 2 for the tetraisopentylammonium poly(vinyl sulfate) hydrate; around 11 °C and 35 for the tetraisopentylammonium poly(styrenesulfonate) hydrate; and 12—13 °C and 37 ± 2 for the tetraisopentylammonium ethyl sulfate hydrate, respectively. The formation of the hydrate phase around the tetraisopentylammonium cation attached to a surface of cation-exchange resins was also examined.
  • Fujio Takahashi, Yasuzo Sakai, Satoru Tsuchida
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3589-3592
    Published: 1993
    Released: August 16, 2006
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    The diamagnetic susceptibilities of various series of organic compounds containing one or two ionic functional groups were measured by Guoy’s method. The diamagnetic susceptibilities of ionic functional groups in organic compounds were determined by calculations according to an additive property of the magnetic susceptibility in a combination of Pascal’s method with the diamagnetic susceptibilities of Na+, K+, Cl, and Br, which are given by Pascal. The results showed that the diamagnetic susceptibilities of ·COO, ·SO3, ·NH3+, and ·N(CH3)3+ are −12.3 × 10−6, −29.2 × 10−6, −13.0 × 10−6, and −39.8 × 10−6 cm3 mol−1, respectively. It became possible to estimate the diamagnetic susceptibilities of organic compounds containing ionic bonds consisting of the above-mentioned ionic functional groups.
  • Yoshiko Kawamura, Jun Yamauchi, Hiroaki Ohya-Nishiguchi
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3593-3599
    Published: 1993
    Released: August 16, 2006
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    1-(o-Substituted phenyl)-3,5-diphenyl-5-formazans form various kinds of complexes. The copper(II) complexes of 1,3,5-triphenyl-5-formazan and 1-(p-Cl and o-CH3)-3,5-diphenyl-5-formazans (Group I) showed about 0.012 cm−1 of the parallel component of the copper(II) ESR splitting constant; those of the copper(II) complexes of 1-(o-Cl and o-Br)phenyl-3,5-diphenyl-5-formazans (Group II) were 0.018 cm−1. The f-values in the near-infrared region of the former complexes were almost 10-times larger than those of the latter complexes. The difference was attributed to a tetrahedral distortion of about 65—70 degrees from the planar structure in Group I; the complexes of Group II, however, were almost planar. The complexes of 1-(o-OH and o-COOH)phenyl-3,5-diphenyl-5-formazans (Group III) showed exchange interactions between two copper(II) ions with exchange energies of −375 and +33.5 cm−1 for the former and the latter complexes of Group III, respectively. Referring to the exchange and dipolar interactions, the Cu–Cu distances and the Cu–O–Cu bridging angles are discussed.
  • Masamichi Fujihira, Masahiro Yanagisawa, Toshihiro Kondo
    1993 Volume 66 Issue 12 Pages 3600-3605
    Published: 1993
    Released: August 16, 2006
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    In order to estimate the inner potential difference of an electrical double layer (EDL) created between the ionic hydrophilic head group of the amphiphile and its counter ion, the electrochemical characteristics of the ferrocene derivatives solubilized in three kinds of micelles were measured, and are discussed so as to clarify the effect of the EDL on the electron transfer through the interface.
  • Tatsuya Takagi, Koichi Tange, Takahiro Jikihara, Norihisa Onozawa, Kaz ...
    1993 Volume 66 Issue 12 Pages 3606-3612
    Published: 1993
    Released: August 16, 2006
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    Nishisato’s Dual Scaling Method for successive categories data has been revised in order to apply it to quantitative structure–activity relationships. The revised version can give category values of successive categories, even though the original one can give only boundary values between two adjacent successive categories. The new version can be applied to an analysis of the antimicrobial activities of polymethylene bi(pyridineamine) derivatives, which are potential agents for controlling and/or preventing the formation of dental plaque. The results show that the proper molecular length of the agents leads to the maximum antimicrobial activity.
  • Norio Kimura, Setsuo Takamuku
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3613-3617
    Published: 1993
    Released: August 16, 2006
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    The one-electron reduction of benzyl halides (BzX; X = F, Cl, Br) by solvated electrons in 2-methyltetrahydrofuran has been investigated by using a pulse radiolysis technique at different temperatures above 77 K. The radical anions of BzX (λmax = 300 nm) formed by the capture of an electron in the π*-orbital of the benzene ring dissociate into Bz· (λmax = 320 nm) and X via Bz/X complexes (λmax = 340 nm for BzCl and 370 nm for BzBr). The corresponding species were observed with 4-phenylbenzyl halide at 85 K and below. A spectral change observed at 95 K has been attributed to a structural change of the biphenylyl group. The dissociation rate of the radical anions increased in the order BzF < BzCl < BzBr. On the basis of these results, the reaction mechanism is discussed.
  • Motohiro Jyo-o, Hideki Takeda, Kenji Omiya, Yo-ichi Ishikawa, Shigeyos ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3618-3626
    Published: 1993
    Released: August 16, 2006
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    In the gas phase at room temperature, the coordination process of NH3, C2H4, CF4, SF6, and Xe onto “naked” W(CO)5, selectively prepared by pulsed 355-nm laser photolysis of W(CO)6, was investigated by laser-based time-resolved infrared absorption spectroscopy. W(CO)5 reacted with these reactant gases, except for CF 4 and SF6, to make a simple coordination complex, W(CO)5(L), where L is NH3, C2H4, or Xe. The bimolecular rate constants for these reactions were (5.6 ± 0.6) × 106 Torr−1 s−1 for W(CO)5 + NH3, (2.8 ± 0.5) × 106 Torr−1 s−1 for W(CO)5 + C2H4, and (1.0 ± 0.3) × 105 Torr−1 s−1 for W(CO)5 + Xe. W(CO)5Xe was unstable owing to its weak interaction with the coordinatively unsaturated tungsten center, the unimolecular decomposition rate of which was about 1.0 × 105 s−1, but W(CO)5(NH3) and W(CO)5(η2-C2H4) were stable under our experimental conditions. The band shifts of C–O stretching modes observed in the coordination of NH3 as a typical σ-donor, C2H4 as a typical π-acceptor, and Xe as a weak σ-donor could interpreted by MO considerations.
  • Sadakatsu Nishikawa, Shirou Morinaga, Masaki Yoshio
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3627-3632
    Published: 1993
    Released: August 16, 2006
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    Ultrasonic velocity at 1.92 MHz has been measured precisely in 1,2-dimethoxyethane (DME), acetonitrile (AN), and propylene carbonate (PC) solutions of lithium tetrafluoroborate (LiBF4) and in DME solution of lithium hexafluoroarsenate (LiAsF6) at 25 °C. The molar relative sound velocity for the LiBF4 solution has been found to show a clear inflection in the DME solution at 0.01 mol dm−3 and in the AN one at 0.02 mol dm−3 concentration though such an inflection has not been found in PC solution. The inflection for DME solution of LiAsF6 is found near 0.0013 mol dm−3. These sound velocity inflection points are believed to be due to formation of triple ions or dimers (quadrupoles) in solvents of low dielectric constants.
    Ultrasonic absorption coefficients in DME solutions of LiAsF6 and LiBF4 have been measured in the frequency range from 8.5 to 220 MHz by a pulse method as a function of their concentration. A single relaxational absorption has been observed in both solutions. In DME solution of LiBF4, the observed relaxational absorption mechanism has been attributed to the dimerization reaction, as reported by Maaser et al. (J. Phys. Chem., 88, 5100 (1984)). Our determination of the rate and thermodynamic constants, however, has taken into account the presence of triple ions.
    The results in LiAsF6 solutions are compared to those reported by Farber et al. (J. Phys. Chem., 87, 3515 (1983)) in the concentration range higher than 0.1 mol dm−3. At concentrations lower than that, however, a phenomenon with a concentration dependent relaxation frequency has been found. From a consideration of various reaction models, it has been concluded that the relaxation is associated with formation of triple ions in solution. The rate and thermodynamic parameters have been determined from the concentration dependence of the relaxation frequency and the maximum absorption per wavelength.
  • Shin-ya Takane, Takayuki Fueno
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3633-3638
    Published: 1993
    Released: August 16, 2006
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    Potential energy profiles of the radical substitution reactions of H2S with some atomic radicals X (X = H, O, F) and of CH3SH with the hydrogen atom have been investigated by ab initio molecular orbital calculations employing the 6-31G** basis sets. All the reactions studied have proved to be elementary reactions with no intermediate adducts involved. At the MRD-CI level using the 6-31G** plus the Rydberg s and p orbitals on sulfur, the activation energies of the homolytic substitution reactions H2S + X → H + HSX are calculated to be 50, 127, and 104 kJ mol−1 for X = H, O, and F, respectively, which are uniformly higher than those calculated for the hydrogen abstraction reactions H2S + X → SH + XH. For the substitution reaction CH3SH + H → CH3 + H2S, however, the activation energy calculated is as low as 19 kJ mol−1, which is even slightly lower than that for the abstraction CH3SH + H → CH3S + H2. The predicted prevalence of the homolytic substitution reaction of CH3SH over the hydrogen abstraction is qualitatively in harmony with observations.
  • Baburao Shankarrao Mohite, Jaykumar Malgonda Patil, Dnyandeo Namdeo Za ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3639-3642
    Published: 1993
    Released: August 16, 2006
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    A very simple method has been developed for the column chromatographic separation of uranium(VI) using poly(dibenzo-18-crown-6). The adsorption studies were carried out from hydrochioric acid medium in the concentration range of 0.5—10.0 mol dm−3. The adsorption of uranium(VI) started from 3.0 mol dm−3 hydrochloric acid and was quantitative from 5.5—10.0 mol dm−3 hydrochloric acid. Various eluting agents such as hydrobromic acid, perchloric acid, sulfuric acid, acetic acid were used for the elution of uranium(VI). The capacity of poly(dibenzo-18-crown-6) for uranium(VI) was found to be 2.5 mmol g−1 of crown polymer. Uranium(VI) was separated from large number of elements from the binary as well as from multicomponent mixtures. The method was applied to the analysis of uranium from real samples.
  • Hideki Masuda, Nobuhiro Fukushima, Hisahiko Einaga
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3643-3647
    Published: 1993
    Released: August 16, 2006
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    Full geometry optimizations have been carried out for the complex formations of Cu+ and Cu(2,2′-bipyridine)+ with CO2 by using the density functional methods. The calculation demonstrated that the end-on coordination mode was mainly favored for all cases, while the binding of 2,2′-bipyridine (bpy) to Cu(CO2)+ largely labilized the end-on coordination mode and stabilized the in-plane side-on coordination mode. The detailed examination of the population analysis indicate that the coordination of bpy to Cu+ weakens the electron donating character of CO2 to Cu+ and promotes the important participation of π-back-donative interaction from the metal ion to CO2.
  • Kenji Waizumi, Hideki Masuda, Hisahiko Einaga, Nobuhiro Fukushima
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3648-3651
    Published: 1993
    Released: August 16, 2006
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    The structures and the formation energies of [MCl4]2− (M = Cr, Mn, Fe, Co, Ni, Zn) have been examined by the density functional method. The optimized structures of [MnCl4]2−, [CoCl4]2− and [ZnCl4]2− are a regular tetrahedron with the M–Cl distances of 236, 227, and 231 pm, respectively. The structures of [CrCl4]2− and [FeCl4]2− are a flattened tetrahedron with the M–Cl distances of 236 and 231 pm, respectively, and with the flattening angles of 156 and 112°, respectively, while that of [NiCl4]2− is a tetrahedron elongated along an S4 axis with the Ni–Cl distance of 226 pm and the corresponding angle of 97°. The formation energies of [MCl4]2− have been compared with their experimental data, and the relative energies of the transformation from [M(H2O)6]2+ to [MCl4]2− are also evaluated in connection with the stability of the anions in aqueous solutions.
  • Toshiki Taya, Tsukasa Sakamoto, Kunio Doi, Makoto Otomo
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3652-3661
    Published: 1993
    Released: August 16, 2006
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    The acid-base equilibria of twenty-one hydrazones substituted by phenyl, pyridyl and/or quinolyl groups have been investigated in aqueous solutions over the region of H to H0 acidity function by a spectrophotometric method at 25 °C. For 2-pyridinecarbaldehyde 2-(5-substituted)pyridylhydrazones, although the proton dissociation of the neutral species (HL) satisfied a Hammett correlation, those of H2L+ and H3L2+ did not. The thermodynamic parameters for the proton dissociations of H2L+ and H3L2+ of seven representative liqands were determined by a temperature-coefficient method at 25 °C and an ionic strength of 0.1 (KCl). The enthalpy and entropy changes for the proton dissociations of H3L2+ and H2L+ were influenced by the steric effects of the methyl group and/or the introduced quinolyl ring. An analysis of the pH dependence of the 1H NMR signals for three hydrazones in an acetone-d6–D2O solution gave more profitable information concerning the fine structures of HL, H2L+, and H3L2+. Each 1H and 13C NMR chemical shift of some ring-substituted methyl derivatives (HL form) in a dioxane–D2O solution has been briefly assigned. On the other hand, a single-crystal X-ray analysis, 1H NMR data in chloroform-d and thermodynamic data for di-2-pyridyl ketone 2-pyridylhydrazone (DPPH) suggested that the intramolecular hydrogen bond in the DPPH molecule is broken by the addition of a proton to the H2L+ species in an aqueous solution.
  • Tsutomu Mizuta, Jun Wang, Katsuhiko Miyoshi
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3662-3670
    Published: 1993
    Released: August 16, 2006
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    The crystal and molecular structures of three TiIII-edta complex salts (edta = ethylenediamine-N,N,N′,N′-tetraacetate), violet Ba[Ti(edta)(H2O)]Cl·6H2O (I), reddish violet Na2[Ti(edta)(H2O)]2·NaCl·7H2O (II), and purple K[Ti(edta)(H2O)]·2.5H2O (III), were determined by a single crystal X-ray diffraction method. The crystal data are as follows: I: Monoclinic, P21/a, a = 14.480(2), b = 19.760(3), c = 7.517(1) Å, β = 94.21(1)°, Z = 4; II: Monoclinic, P21, a = 18.176(3), b = 12.688(3), c = 8.045(2) Å, β = 93.05(2)°, Z = 2; III: Orthorhombic, Fdd2, a = 15.453(3), b = 60.247(8), c = 7.237(2) Å, Z = 16. It was found that all of these complexes have seven-coordinate and distorted mono-capped trigonal-prismatic (C2v-CTP) structures, in contrast to the corresponding dark-blue sodium salt, Na[Ti(edta)(H2O)]·2H2O, which was previously confirmed to be also seven-coordinated, but to have an approximately pentagonal-bipyramidal(PB) structure. The delicate color changes of the TiIII-edta complex salts observed in the solid state when the counterion is varied are due to an accompanying subtle modification in the coordination geometry around the TiIII ion. The kinetic lability and acid-base behavior of the TiIII-edta complex in solution reported earlier are accounted for by the presence of a labile water molecule in the first coordination sphere.
  • Ritsuro Miyawaki, Izumi Nakai, Kozo Nagashima
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3671-3675
    Published: 1993
    Released: August 16, 2006
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    The crystal structure of Na3Sb7O9Se3·Sb0.319(H2O,OH)3 has been determined using a single crystal prepared by hydrothermal synthesis to a conventional R = 0.043, Rw = 0.039 for 1556 reflections. It is hexagonal with a space group of P63; a = 14.422(4), c = 5.5448(8) Å, Z = 2. The structure consists of infinite tunnels formed by the linkages of SbO3 pyramids. SbSe3 pyramids among the tunnels connect the tunnels to form a three-dimensional structure. Na atoms were on the inside wall of the tunnel. It was revealed that statistically occupied Sb(H2O,OH)6-octahedra are located at the center of the tunnel. Two statistical sites for the Sb atom of the SbSe3 pyramids are pointed out.
  • Tohru Saitoh, Haruki Segawa, Tamio Kamidate, Hiroto Watanabe, Kensaku ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3676-3679
    Published: 1993
    Released: August 16, 2006
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    The distribution constants of 2-(2-pyridylazo)phenol (PAP), 2-(2-pyridylazo)-5-methylphenol (PAP-5Me), and metal chelates with PAP and PAP-5Me between aqueous micellar psuedophases were evaluated in aqueous micellar solutions of Triton X-100. The distribution constants were found by measurement of equilibrium shifts in acid-base and complexation reactions in the presence of micelles at an ionic strength of 0.1 ((Na+, H+) ClO4) and at 293 ± 1 K. The metal chelates (vanadium(V), nickel(II), and iron(II)) had a linear correlation between their logarithmic distribution constants and their van der Waals volumes. PAP and PAP-5Me had a different kind of correlation from the metal chelates did. These results were explained by the difference in the part of the micelles into which hydrophobic chelates and hydrophilic chelating reagents were incorporated.
  • Teruo Hinoue, Goro Imamura, Yu Yokoyama
    1993 Volume 66 Issue 12 Pages 3680-3685
    Published: 1993
    Released: August 16, 2006
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    The reflectivity was measured at the interface between the glass substrate and the Brilliant Blue (BB) or Methylene Blue (MB) aqueous solution as a function of the angle of incidence at 632.8 nm from a He–Ne laser. The relationship between the reflectivity and the angle of incidence was analyzed by an approximate expression derived from the basic theory of internal reflection spectroscopy. On the other hand, a plot of the reflectivity against the effective thickness was used as a ready diagnosis of the dye adsorbed by the glass substrate. From the results it has been suggested that BB is not adsorbed, whereas MB is. Based on a parameter obtained experimentally, the thickness of the adsorption layer was determined to be 0.65 ± 0.18 nm. This result suggests that the MB cation is adsorbed parallel to the glass surface to form a monomolecular layer. Further, it has been revealed from a similar analysis that the addition of a cationic surfactant with a long alkyl chain in the MB solution prevents the adsorption of MB by the glass substrate, whereas the addition of an anionic surfactant with a long alkyl chain promotes adsorption.
  • Masakazu Kita, Kazuo Kashiwabara, Junnosuke Fujita, Saeko Kurachi, Shi ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3686-3692
    Published: 1993
    Released: August 16, 2006
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    The reaction of elemental sulfur S8 with [Co(dmpe)2](BF4)2 in a mixture of methanol and benzene gave a novel S,S′-coordinated disulfur oxide cobalt(III) complex, [Co(S2O-S,S′)(dmpe)2]ClO4 (1), and a dimethyldithiophosphinato complex, [Co(S2PMe2)2(dmpe)]BF4 (2). The molecular structures of these complexes were determined by X-ray structure analyses. Crystal data for complex 1: monoclinic, P21/n, a = 14.702(3), b = 11.645(1), c = 14.333(2) Å, β = 109.90(2)°, V = 2307.4(2) Å3, Dx = 1.55, Dm = 1.54(3) g cm−3, Z = 4, R = 0.039 for 4542 reflections. Crystal data for complex 2: orthorhombic, Pnc2, a = 13.383(3), b = 12.333(2), c = 13.742(3) Å, V = 2268.1(8) Å3, Dx = 1.60, Dm = 1.59(2) g cm−3, Z = 4, R = 0.075 for 2060 reflections. The central sulfur atom of the S–S–O group in complex 1 exerts a larger trans influence than does the terminal sulfur.
  • Hideo Kise, Tohru Nagashima
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3693-3698
    Published: 1993
    Released: August 16, 2006
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    The enantiospecificity of α-chymotrypsin (CT) at S′1 site in aqueous–organic media was investigated for peptide synthesis from N-acetyl-L-tyrosine ethyl ester (ATEE) as an acyl donor and alanine or serine derivatives as acyl acceptors. It was found that catalytic activity of CT is a function of nature of organic solvent, and, among the solvents used, CT exhibited high activity in t-butyl alcohol, acetone, and acetonitrile. The relative reactivity of L-alaninamide as an acyl acceptor to that of D-isomer was also significantly dependent on nature of solvent. CT exhibited high specificity to L-isomer in these three organic solvents. The enantiospecificity is also a function of water content in reaction media. In acetonitrile, the maximum reaction rates of ATEE with L- and D-alaninamide were obtained at 10 and 6% water, respectively, and relative reactivity of D-isomer increased with decrease in water content. Structural effects of acyl acceptors on their reactivity are striking and discussed in terms of stability of their complexes with the acyl-enzyme intermediate.
  • Takahisa Machiguchi, Toshio Hasegawa, Yuichi Kano
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3699-3706
    Published: 1993
    Released: August 16, 2006
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    Several 2-substituted tropothiones (2,4,6-cycloheptatriene-1-thiones) having an electron-donating group (Me, Ph, NH2, NHMe, OH, OMe, or SMe) were synthesized by direct sulfurization from the corresponding tropones in a one-pot reaction. In contrast to the instability of the parent tropothione (1a), most of these 2-substituted derivatives were insensitive to air and were thermally stable compounds which can be handled at room temperature. These tropothione derivatives were characterized by spectroscopic and dipole moment measurements. The IR spectra showed ν(C=S) vibrations at around 1100—1040 cm−1. The UV-vis spectra displayed three π–π* transitions accompanied by n–π* transitions. The 400-MHz 1H NMR spectra of the thiones showed that only protons at the 7 position resonate well-separated downfield from the other ring protons due to the strong C=S anisotropy. In the 13C NMR (100.6 MHz) spectra, the C=S carbon signals appeared at < δ = 183 and the other ring carbons resonated at δ = 154—112. Variable-temperature 13C as well as 14N NMR spectroscopic studies clarified that 2-amino- and 2-(methylamino)tropothiones exist as an equilibrium mixture of the thione and enethiol structures in an approximate ratio of 64 : 36. This is different from the results of a previous investigation showing that the structures exist as the thione form exclusively. Dipole moments of some derivatives of 1a were measured and compared with those of the corresponding tropones. These tropothione derivatives obtained were more ionic than both the parent compound 1a and the corresponding tropones.
  • Tadamitsu Sakurai, Mitsuko Okamoto, Hiroyasu Inoue
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3707-3711
    Published: 1993
    Released: August 16, 2006
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    The title hydroxylamine (SO2NT) underwent singlet-sensitized photolysis in the presence of pyrene to give rearrangement and fragmentation products. SO2NT was found to quench both pyrene-monomer and -excimer fluorescences. The presence of a sulfonyl group with a semipolar-bond character in SO2NT was suggested to be responsible for a pronounced termolecular interaction between the pyrene excimer and SO2NT to result in a quenching of the excimer emission. An energetic consideration of the pyrene monomer and excimer as well as the N–O bond cleavage of SO2NT allows us to propose that not the excimer, but the monomer, activates SO2NT to induce its sensitized decomposition. An analysis of the solvent polarity effects on both limiting the quantum yields for the appearance of the products and the quenching of pyrene fluorescence by SO2NT demonstrated that the sensitized reaction proceeds by a singlet-exciplex mechanism in benzene, whereas an electron-transfer mechanism predominates in acetonitrile.
  • Yasuhiro Tanoue, Akira Terada, Hiroshige Taniguchi, Tadashi Okuma, Hir ...
    1993 Volume 66 Issue 12 Pages 3712-3715
    Published: 1993
    Released: August 16, 2006
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    The reaction of naphthazarin with cyclic enol ethers in acetic acid in the presence of BF3·OEt2 gave naphthazarin derivatives such as cycloshikonin, having a cyclic ether substituent, in one step. Cyclic enol ethers did not attack the quinone ring of naphthazarin but the benzene ring, and the corresponding naphthazarin derivatives were produced after tautomerization. This reaction was applicable to juglone to give juglone derivatives bearing a cyclic ether substituent.
  • A. A. Geies, A. A. Abdel-Hafez, J. C. Lancelot, H. S. El-Kashef
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3716-3723
    Published: 1993
    Released: August 16, 2006
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    3,5-Dibenzylidene-1-isopropy1-4-piperidinone (1) reacts with cyanothioacetamide to give 1,6-naphthyridine-2(1H) thione derivative 2. Reaction of 2 with halo ketones or halo esters followed by ring closure gives thieno[2,3-b][1,6]naphthyridine derivatives 5ai, which are used as versatile intermediates in the synthesis of related heterocyclic ring systems as pyrimidothienonaphthyridines 10, 11, 14, and 15, oxazinothienonaphthyridine (13) and triazinothienonaphthyridine (9).
  • Yosuke Nakamura, Hiizu Iwamura
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3724-3728
    Published: 1993
    Released: August 16, 2006
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    2,2″,5,5″-Tetrakis(dimethylamino)-p- and m-terphenyls (1 and 2), in which two N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) moieties are linked through p- and m-phenylene units, respectively, were synthesized, and their CT complexes with TCNQF4 were prepared. In the complexes, 1 and 2 possess two S = 1/2 spins per molecule. The intramolecular interaction between the spins of the two TMPD moieties was found to be antiferromagnetic (2J/k = −42 K) in 1, and ferromagnetic (2J/k = 240 K) in 2.
  • Kaoru Suzuki, Hideo Kitagawa, Teruaki Mukaiyama
    1993 Volume 66 Issue 12 Pages 3729-3734
    Published: 1993
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    In the presence of active cationic species generated from silicon(IV) chloride and silver perchlorate, carboxylic acids or their trimethylsilyl esters react with p-trifluoromethylbenzoic anhydride to form corresponding mixed anhydrides in situ. Then the catalytic Friedel–Crafts acylation reaction between initially formed mixed anhydrides and coexisted aromatic compounds smoothly proceeds at room temperature to afford the corresponding aromatic ketones in high yields. The above two sequential reactions are effectively promoted by the active silicon(IV) catalyst under mild conditions.
  • Noritaka Abe, Akikazu Kakehi
    1993 Volume 66 Issue 12 Pages 3735-3741
    Published: 1993
    Released: August 16, 2006
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    Syntheses and cycloadditions of ethyl 2-(benzylidene)hydrazino-1-azaazulene-3-carboxylates were investigated. Condensations of ethyl 2-hydrazino-1-azaazulene-3-carboxylate with benzaldehyde and p-methoxybenzaldehyde gave corresponding hydrazones in good yields. Reactions of ethyl 2-(benzylidene)hydrazino-1-azaazulene-3-carboxylate (2a) and ethyl 2-(p-methoxybenzylidene)hydrazino-1-azaazulene-3-carboxylate with dimethyl acetylenedicarboxylate gave novel 1 : 2-adducts, 4a,11,11a-triazaindeno[5,6-a]azulene derivatives and 2-methoxycarbonylimino-1-(2-pyrrolylmethyl)-1-azaazulene derivatives as major products. Reaction of 2a with electron deficient olefins (tetracyanoethylene, N-methylmaleimide) gave no cycloadduct but a cyclization product of 2a, 3-phenyl-1,2,3a-triazacyclopent[a]azulene-9-carboxylate. The structures of the obtained compounds were analyzed by inspections of their physical and spectral data, and by single-crystal X-ray analyses of some of these compounds. The reaction mechanisms of these reactions are discussed.
  • Akira Mori, Kanji Kubo, Hitoshi Takeshita
    1993 Volume 66 Issue 12 Pages 3742-3746
    Published: 1993
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    Treatment of 2,3-dihydro-4aH-cyclohepta-1,4-dithiin with triphenylmethyl tetrafluoroborate followed by condensation with α-bromomalononitrile in pyridine afforded 5- and 7-(dicyanomethylene)-2,3-dihydrocyclohepta-1,4-dithiins in good yields. When changing the solvent to acetonitrile, the products obtained were 5- and 6-(2,2-dicyanoethyl)-2,3-dihydro-1,4-benzodithiins. This new method was applicable to the general synthesis of dicyanoheptafulvenes from tropylium salts.
  • Toshiyuki Tamai, Kazuhiko Mizuno, Isao Hashida, Yoshio Otsuji
    1993 Volume 66 Issue 12 Pages 3747-3754
    Published: 1993
    Released: August 16, 2006
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    Photoreactions of arylmethylsilanes, -germane, and -stannane with 1,4-dicyanonaphthalene (DCN) and 9,10-dicyanoanthracene (DCA) were studied under various conditions. The arylmethylation of DCN and DCA occurred in the photoreaction under nitrogen atmosphere, whereas the oxygenation of the arylmethyl organometallic compounds occurred in the photoreaction under oxygen atmosphere. Key intermediates in these reactions in acetonitrile were radical ions which were generated via photoinduced electron transfer from the arylmethyl organometallic compounds to the excited singlet of DCN or DCA. The cleavage of the carbon–metal bond of the radical cations of the arylmethyl compounds resulted in the formation of arylmethyl radicals. The radicals reacted then with the radical anions of DCN and DCA to produce the arylmethylated compounds or reacted with oxygen to produce the oxygenated compounds. The efficiency of the photoreactions was affected by solvents and added materials to the reaction systems. In the photoreactions in benzene, the exciplexes of the type 1[A–ArCH2MR3]* or the triplexes of the type [A–C6H6–ArCH2MR3]* (A = DCN, DCA) were involved as intermediates. The reactivity features of the photoreactions are discussed.
  • Kazuyuki Nakata, Tsutomu Miyata, Tetsuro Jintoku, Akira Kitani, Yuki T ...
    1993 Volume 66 Issue 12 Pages 3755-3759
    Published: 1993
    Released: August 16, 2006
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    The mixed catalyst Pd(OAc)2–Cu(OAc)2 promotes the carboxylation of cyclohexane and propane with CO in higher yield than either a Pd(II) or Cu(II) catalyst alone. The mixed catalyst has the highest activity when the ratio of Cu(II)/Pd(II) is more than unity. The carboxylations of p-xylene with Pd(II)–Cu(II) and Pd(II) afford 2,5-dimethylbenzoic acid, but no carboxylic acid is detected in the reaction with Cu(II), giving rise to p-xylene dimer as the major product instead. Clear isotope effect (3.0—3.2) is observed in the reactions of cyclohexane with Pd(II)–Cu(II) and Pd(II), unlike the reaction with Cu(II) (1.0).
  • Takahiko Akiyama, Hiroaki Shima, Masatoshi Ohnari, Tadashi Okazaki, Sh ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3760-3767
    Published: 1993
    Released: August 16, 2006
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    The methyl ether of cyclitols with vicinal hydroxyl group was cleaved chemoselectively in preference to both cis- and trans-cyclohexylidene moieties by AlCl3n-Bu4NI to afford parent alcohols in good yields. (−)-Conduritol F was prepared from L-quebrachitol, an optically active cyclitol from the serum of rubber trees, in five steps by use of the demethylation reaction. The first chiral synthesis of (+)-conduritol B and the total synthesis of cyclophellitol, a novel β-glucosidase inhibitor, are described.
  • Kazuyuki Kasuga, Takuji Hirose, Toshikazu Takahashi, Kazuhisa Hiratani
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3768-3772
    Published: 1993
    Released: August 16, 2006
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    Several new N-(8-quinolyl)-substituted diamide compounds were synthesized from α-amino acids and their Cu(II) transport abilities as carriers through liquid membranes were investigated. The Cu(II) transport ability of the carrier is affected by the α-substituent of the amino acid. Diamides derived from alanine and phenylalanine have good Cu(II) transport abilities.
  • Atsuhiro Osuka, Run-Ping Zhang, Kazuhiro Maruyama, Takeshi Ohno, Koich ...
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3773-3782
    Published: 1993
    Released: August 16, 2006
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    Synthesis of fixed-distance triads consisting of zinc porphyrin (ZnP), metal-free porphyrin (H2P), and pyromellitimide (PIm) or 1,4 : 5,8-naphthalenetetracarboximide (NIm) is described. The ZnP and H2P moieties are bridged by aromatic spacers such as 1,4-phenylene, 4,4′-biphenylylene, methylenebis(1,4-phenylene), and bicyclo[2.2.2]octane-1,4-diylbis(1,4-phenylene) groups. The steady-state fluorescence spectra indicated the occurrence of intramolecular singlet-singlet energy transfer form the ZnP to the H2P. Formation of long-lived charge-separated states (ZnP)+–H2P–(PIm) and (ZnP)+–H2P–(NIm) with lifetimes of 0.14—80 μs in THF was observed by nanosecond to microsecond transient absorption spectroscopy. The lifetimes of the (ZnP)+–H2P–(Im) states depend on the distances between the charged sites as well as the energy gaps between the ion pair and the ground state.
  • Shigeru Nagahara, Keiji Maruoka, Hisashi Yamamoto
    1993 Volume 66 Issue 12 Pages 3783-3789
    Published: 1993
    Released: August 16, 2006
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    The hydroalumination of a terminal allene, 1,2-nonadiene, with LiAlH4 in THF using [TiCl2(Cp)2], TiCl4, TiCl3, ZrCl4, and [ZrCl2(Cp)2] catalysts afforded a wide variety of deuterated species by quenching hydroalumination products with D2O, while PhB(OH)2-catalyzed hydroalumination with AlHCl2 in ether gave >95% pure 1-nonene-3-d as predominant product (92%) in high yield. The allylation of benzaldehyde using the PhB(OH)2-catalyzed hydroalumination product suggested that the resulting hydroalumination product may be the allylaluminum compound, 2-nonenylaluminum dichloride. Allylation of trans-cinnamaldehyde using this allylaluminum compound proceeded with high regioselectivity, leaving the ketone functionality intact. Allylative ring-opening reaction of epoxides was less regioselective. The combination of catalytic PhB(OH)2 with AlHCl2 also was effective for the regioselective hydroalumination of the disubstituted allenes, vinylidenecyclohexane and 1-trimethylsilyl-1,2-nonadiene, although the trisubstituted allene, 1-butenylidenecyclohexane, showed nonregioselective orientation results.
  • Michinori Oki, Yasushi Taguchi, Toshiyuki Okamoto, Tsutomu Miyasaka, K ...
    1993 Volume 66 Issue 12 Pages 3790-3796
    Published: 1993
    Released: August 16, 2006
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    Rotational isomers of the title carboxylic acid were treated with lead(IV) acetate in the presence of lithium chloride or benzyltriethylammonium chloride in benzene. The ap-isomer afforded a chloride, which was expected from normal chlorodecarboxylation, in addition to a cyclized compound, which was produced by radical addition to a near-by benzene ring. By contrast, the sc-isomer afforded no normal chloride, but a benzylic chloride, which was formed by hydrogen transfer to the radical site in the 9-substituent from the benzylic position, was the main product. In addition, an acetonyl ester of the original sc-carboxylic acid and a small amount each of 1-acetoxymethyl compound and an olefin were obtained. Possible mechanisms of formation of these compounds are discussed on the ground of the stability of the benzylic radical and participation of a methyl group.
  • Eisaku Nomura, Hisaji Taniguchi, Yoshio Otsuji
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3797-3801
    Published: 1993
    Released: August 16, 2006
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    The binding properties of p-(phenylazo)calix[n]arenes (n = 6 and n = 4) for metal ions have been studied. The calixarenes show a highly selective binding ability toward Ag+, Hg+, and Hg2+. This property can be explained in terms of a metal ion-induced azo/hydrazone tautomerism. The Ag+ ion forms complexes with the azocalixarenes by binding with their hydrazone tautomers.
  • Tadashi Mizutani, Koji Takahashi, Tsutomu Kato, Jiro Yamamoto, Nasuo U ...
    1993 Volume 66 Issue 12 Pages 3802-3805
    Published: 1993
    Released: August 16, 2006
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    The rates of dissolution of silica gel in aqueous alkaline solutions containing pyrocatechol were measured. At pH 10, all of the silica gel was dissolved in the presence of pyrocatechol at 25 °C for 48 h (SiO2 0.3 g and pyrocatechol 0.04 mol in 15 ml of water). The rates of silica-gel dissolution increased with increasing pyrocatechol concentration. Four moles of pyrocatechol were needed to dissolve one mole of SiO2. The rate of dissolution was first order in solid SiO2 concentration. Langmuir-type adsorption of pyrocatechol to the silica-gel surface was assumed to explain the rate dependence on the pyrocatechol concentration.
  • Tohru Kanno, Masayoshi Kobayashi
    1993 Volume 66 Issue 12 Pages 3806-3807
    Published: 1993
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    The surface basicity of alkali metal-modified MgO was evaluated by both TPD and IR techniques and a good correlation between the two results was obtained, in which Li showed the distinct modification effect on MgO.
  • Kazuo Mukai, Shigeru Ohbayashi, Shin-ichi Nagaoka, Takehiro Ozawa, Nag ...
    1993 Volume 66 Issue 12 Pages 3808-3810
    Published: 1993
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    Molecular structures of vitamin E derivatives were analyzed with X-ray diffraction. The relationship between the antioxidant activity and the molecular structure of vitamin E is discussed.
  • Kohki Ebitani, Munehiro Morokuma, Jong-Ho Kim, Akira Morikawa
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3811-3812
    Published: 1993
    Released: August 16, 2006
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    The activity of the photocatalytic N2O decomposition into N2 and O2 on a degassed Cu-containing ZSM-5 zeolite (percent exchange, 145%) corresponded well to the amount of monovalent copper (Cu+) present on the Cu/ZSM-5, which was titrated by the irreversibly adsorbed CO at 273 K.
  • Naotake Ogawa, Hiroyuki Taguchi, Takatoshi Sato
    1993 Volume 66 Issue 12 Pages 3813-3814
    Published: 1993
    Released: August 16, 2006
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    2-Chloromaleic anhydride and styrene were copolymerized by solution polymerization. The copoly(styrene/2-chloromaleic anhydride) was dehydrochlorinated by heating under reduced pressure and a polymer having a structure similar to the maleic anhydride moiety in the polymer chain was obtained. The dehydrochlorination was completed by heating at 220 °C for 1 h.
  • Kimio Yoneda, Khoichi Uchiyama, Barry Boettcher, Yoshinobu Inouye
    Type: Accounts
    Subject area: AI
    1993 Volume 66 Issue 12 Pages 3815-3817
    Published: 1993
    Released: August 16, 2006
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    A new dinuclear copper(II) salicylate, [Cu2(C7H5O2)4]·2C2H5OH·2H2O, was prepared from copper(II) hydroxide and excess salicyclic acid in 80% ethanol. The structure was clarified by a single crystal X-ray analysis.
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