Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 62 , Issue 2
Showing 1-50 articles out of 69 articles from the selected issue
  • Toru Arai, Ken-ich Maruya, Kazunari Domen, Takaharu Onishi
    1989 Volume 62 Issue 2 Pages 349-353
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    CO hydrogenation over mixed oxides of 3A and 4A Groups (Y2O3, La2O3, CeO2, and ZrO2) with 3B Group (Al2O3, Ga2O3, and In2O3) was carried out. The addition of Ga2O3 or In2O3 to Y2O3, La2O3, and CeO2 enhances the formation of light alkenes. An In2O3–CeO2 catalyst shows the highest selectivity (43%) for ethene with the lowest selectivity (0.5%) for ethane in total hydrocarbons produced. The addition of In2O3 to CeO2 results in an increase in activity for the CO hydrogenation reaction. From the results of an ethene hydrogenation reaction over mixed oxide catalysts, the high selectivity for alkene formation over In2O3-containing catalysts is due to a suppression of alkene hydrogenation by the addition of In2O3. Indium in CeO2 is highly dispersed while keeping an oxidation state of +1 or +3 under the reaction conditions.
  • Tooru Taga, Noriko Yamamoto, Katsunosuke Machida
    1989 Volume 62 Issue 2 Pages 354-357
    Published: 1989
    Released: June 27, 2006
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    A crystal of 1,3-dimethyl-5-fluorouracil can be used to solve large amounts of 1,3-dimethyluracil as a solid–solution crystal. The crystal structure has been determined by an X-ray method. The planar molecules are arranged in a parallel sheet, and the molecules within the same sheet interact with each other through short CH···O and CH···F contacts. The short intermolecular C···F distance is 2.999(6) Å. The stability of a mixed crystal could be explained in terms of intermolecular interactions around the fluorine atom.
  • Shin-ichiro Tamura, Nobutoshi Asai, Jun’etsu Seto
    1989 Volume 62 Issue 2 Pages 358-361
    Published: 1989
    Released: June 27, 2006
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    Photochromic processes of 1′-hexyl-5′,8-dimethoxy-3′,3′-dimethyl-6-nitrospiro[2H-1-benzothiopyran-2,2′-indoline] were investigated with laser flash techniques. Photocoloration was found to proceed via the excited singlet state, and the quantum yield of coloration was an order of magnitude smaller than those of ordinary spirobenzopyrans. The main route of the decoloration was found to be the thermal reaction. Remarkably different solvent effects for the thermal fading rate of the colored form were observed, which indicates that the zwitterionic structure is more significant for the new spirobenzothiopyran than ordinary spirobenzopyrans. Repetitive cycles of photocoloration and thermal fading were achieved.
  • Jun Okubo, Toshihiko Hoshi, Isao Ono, Kaori Karube, Michio Kobayashi
    1989 Volume 62 Issue 2 Pages 362-366
    Published: 1989
    Released: June 27, 2006
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    The X-ray photoelectron spectra of the 1:1 and 1:2 salts formed from the triethylammonium cation (TEAH+) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) have been measured and analyzed in order to investigate the electronic structures and conformations of the salts. The N 1s band (398.2 eV) degenerated in the free TCNQ molecule splits into two bands (398.4 eV and 400.3 eV) in the 1:1 salt. This is due to the unequal interactions of the nitrogen atoms of the TCNQ anion radical (TCNQ\ ewdot) with TEAH+. In the 1:2 salt, the degenerated N 1s bands of two free TCNQ molecules split into three bands (398.5, 400.0, and 401.8 eV). This implies that the negative charge is inhomogeneously distributed over two TCNQ molecules, supporting the idea that the electronic structure of the 1:2 salt can be represented approximately as TEAH+–TCNQ\ ewdot–TCNQ0. It is found that, in the 1:2 salt, the neutral TCNQ molecule (TCNQ0) is weakly bound to the TCNQ anion radical (TCNQ\ ewdot) of the strongly bound 1:1 salt, with their molecular planes parallel.
  • Kaori Miyata, Kenichi Nakashima, Motohiko Koyanagi
    1989 Volume 62 Issue 2 Pages 367-371
    Published: 1989
    Released: June 27, 2006
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    From the analysis of emission, excitation, absorption, and 1H NMR spectra of 2,3-butanedione (i.e., biacetyl), it has been established that about two thirds of the molecule in aqueous solutions exists as 3,3-dihydroxy-2-butanone (i.e., a hydrated form of biacetyl). For the first time, two different types of emission are discriminated: Emission is mostly due to the fluorescence spectrum of the monoketone upon irradiation of light with a shorter wavelength than 320 nm while it is due to the strong phosphorescence spectrum of biacetyl itself upon irradiation of light with a longer wavelength than 350 nm. The almost stoichiometric molecular rearrangement from the hydrated (monoketone) form in a water phase to the ordinary (diketone) form in a hydrocarbon phase has been found to take place.
  • Kenichi Imaeda, Toshiaki Enoki, Takehiko Mori, Hiroo Inokuchi, Mitsuru ...
    1989 Volume 62 Issue 2 Pages 372-379
    Published: 1989
    Released: June 27, 2006
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    The electronic properties of charge-transfer (CT) complexes based on a new organic donor MTDTPY with TCNQ and p-benzoquinone derivatives (fluoranil (FLL), chloranil (CHL), bromanil (BRL), and DDQ) have been investigated by means of electrical conductivity, thermoelectric power, ESR, and band calculation. β-MTDTPY–TCNQ, MTDTPY–CHL, and MTDTPY–BRL show a metallic electrical conduction. MTDTPY–CHL and MTDTPY–BRL are the first organic metals among the CT complexes with p-benzoquinone derivatives. The metal–insulator (M-I) transition takes place around 110, 240, and 125 K for β-MTDTPY–TCNQ, MTDTPY–CHL, and MTDTPY–BRL, respectively. The sharp ESR linewidth and large anisotropy of the transfer integral for β-MTDTPY–TCNQ and MTDTPY–CHL suggest a one-dimensional electronic property. Thus, the M-I transition for these complexes is considered to be caused by a Peierls instability. MTDTPY–CHL undergoes a first-order phase transition in the semiconducting phase. This phase transition disappears by applying pressure.
  • Noriaki Funasaki, Sakae Hada, Saburo Neya
    1989 Volume 62 Issue 2 Pages 380-385
    Published: 1989
    Released: June 27, 2006
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    A computer simulation method for gel filtration chromatography (GFC), based on plate theory and mass action law, is developed for rapidly self-associating systems and compared with asymptotic theory. For ovalbumin, a non-associable protein, whose elution volume increases linearly with increasing concentration, the leading boundary is predicted to be broader than the trailing. Computer simulations are used to estimate the aggregation numbers and the equilibrium constants for dimerization of carbonylhemoglobin and hexamerization of α-chymotrypsin. The concentration, Cmin, at the plateau region of the trailing boundary is shown to be close to cmc by asymptotic theory. The present computer simulation and derivative GFC patterns serve to estimate monomer concentration and micellar size of surfactants from analysis of GFC data.
  • Kohshin Takahashi, Teruhisa Komura, Hiroto Imanaga
    1989 Volume 62 Issue 2 Pages 386-391
    Published: 1989
    Released: June 27, 2006
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    The cathodic photocurrents of the film electrodes of ZnPyP3P(3) and ZnPyP3P(4), (PyP3P(n), 5-(2-, 3-, and 4-pyridyl)-10,15,20-triphenylporphyrin, where (n) denotes the position of free bond of pyridyl group), were almost four times larger than that of ZnTPP (TPP, 5,10,15,20-tetraphenylporphyrin) in 0.01 mol dm−3 quinhydrone aqueous solution at pH 5. On the other hand, the very small anodic photocurrent was observed with the film electrodes of ZnTPyP(3) and ZnTPyP(4) (TPyP(n),5,10,15,20-tetra(2-, 3-, and 4-pyridyl)porphyrin). The photoelectrochemical properties of ZnPyP3P(2) and ZnTPyP(2) were distinct from those of other structural isomers, but approximately similar to those of ZnTPP. The conductivities of ZnPyP3P(n) films were about three oders of magnitude larger than those of ZnTPP and ZnTPyP(n) films. It was found from the absorption and resonance Raman spectra that the pyridyl group in porphyrin coordinated to zinc in another porphyrin in the solid films as well as in toluene and dichloromethane solutions. The molecular arrangement of zinc porphyrin in the solid film probably influenced the photoelectrochemical properties and the conductivity.
  • Hazime Saitô, Motoko Yokoi
    1989 Volume 62 Issue 2 Pages 392-398
    Published: 1989
    Released: June 27, 2006
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    High-resolution 13C NMR spectra of a variety of (1→3)-β-D-glucans were recorded in the solid state after lyophilization from DMSO solution in order to study resulting conformations free from the triple-helix conformation. Lyophilization from DMSO solution caused conformational change of laminaran from Laminaria species (‾Dp=38) from the triple helix to the oligomer-type form (form I). On the contrary, single-chain conformation (form II) of high molecular-weight curdlan was unchanged before and after lyophilization from DMSO solution. Further, DMSO induced conformational change of both single-chain (form II) and triplehelical (form III) conformations of acid-degraded curdlan (‾Dp=14) to the form I. These findings support our view that the single-chain conformation is a major form in curdlan powder. We found that these three forms are distinguished by either the 13C spin-lattice relaxation times (T1C’s) of the laboratory frame or proton spin-lattice relaxation times in the rotating frame (TH). In particular, the form I was distinguishable from others by its prolonged T1C values (3.5–12 s) of C-6 carbon. In addition, the TH of the triple helix of annealed curdlan was one order of magnitude longer than that of the single chain, reflecting their difference in the manner of molecular packing.
  • Hirokazu Nakayama, Taro Eguchi, Nobuo Nakamura, Hideaki Chihara, Takas ...
    1989 Volume 62 Issue 2 Pages 399-402
    Published: 1989
    Released: June 27, 2006
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    Temperature dependence of 1H NMR spin-lattice relaxation time was measured in solid 1,4-didecyl-1,4-diazoniabicyclo[2.2.2]octane dibromide and diiodide (C10–DABCO–C10–Br2 and C10–DABCO–C10–I2). 79Br NMR spin-lattice relaxation time and chemical shift measurements in the high-temperature phase were also performed in C10–DABCO–C10–Br2. It was found that the cation rotates isotropically, while the anion diffuses at a correlation time of ca. 10−8 s in the high-temperature phase of C10–DABCO–C10–Br2. The activation energies for these modes are 30 and 34 kJ mol−1, respectively. Methyl reorientation is activated in the low-temperature phase (Ea=11.8 kJ mol−1 in C10–DABCO–C10–Br2 and Ea=12.0 kJ mol−1 in C10–DABCO–C10–I2). Near the phasetransition temperature some motion of decyl chain is observed (Ea=57 kJ mol−1 in C10–DABCO–C10–Br2 and Ea=35.5 kJ mol−1 in C10–DABCO–C10–I2).
  • Takashi Kakiuchi, Masatoshi Nakanishi, Mitsugi Senda
    1989 Volume 62 Issue 2 Pages 403-409
    Published: 1989
    Released: June 27, 2006
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    Electrocapillary curves have been measured at the polarized nitrobenzene–water interface in the presence of dilauroylphosphatidylcholine (DLPC) in the nitrobenzene phase. DLPC formed a saturated monolayer when the concentration of DLPC was above 10 μmol dm−3. The area occupied by a DLPC molecule in the saturated monolayer was 0.93 nm2, indicating that the monolayer was in the liquid-expanded state. The stability of the monolayer was strongly affected by the electrical potential difference across the interface. The monolayer was stable when the interface was negatively polarized, i.e., the potential in the aqueous phase was negative with respect to that in the oil phase. The potential of zero charge shifted to a negative potential as the adsorption of DLPC increased, which indicated the specific adsorption of lithium ions in the aqueous phase to the head group of the DLPC molecules exposed to the aqueous phase. When the interface was positively polarized, the adsorption of DLPC abruptly decreased and the monolayer appeared to be disrupted.
  • Norihiro Ikeda, Eiji Shiota, Makoto Aratono, Kinsi Motomura
    1989 Volume 62 Issue 2 Pages 410-414
    Published: 1989
    Released: June 27, 2006
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    The surface tension of the aqueous solution of dodecyltrimethylammonium chloride (DTAC) and decylammonium chloride (DeAC) mixture was measured as a function of the total molality and composition of the surfactants at 298.15 K under atmospheric pressure. To make clear the miscibility of surfactants, the compositions in the mixed adsorbed film and micelle were calculated by use of the thermodynamic equations developed previously. The results indicated that both adsorbed film and micelle are richer in DTAC molecules than the bulk solution. Furthermore, the composition in the adsorbed film at the critical micelle concentration (cmc) was evaluated and compared with that in the micelle. It was found that the composition of DeAC in the micelle is smaller than that in the adsorbed film. This forms a striking contrast to the previous observation of dodecylammonium chloride (DAC)–DeAC mixture. It was concluded that the structure and size of polar head group of surfactants have a significant influence on the miscibility of surfactants.
  • Ken-ichi Machida, Michio Enyo
    1989 Volume 62 Issue 2 Pages 415-418
    Published: 1989
    Released: June 27, 2006
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    An in situ X-ray diffraction (XRD) technique reported earlier was improved and employed to study the hydride formation in Pd and Pd–Au alloy foils and amorphous Pd–Zr alloy ribbons during cathodic hydrogen charging or its reverse process. The phase transformation from α- to β-PdHx in the Pd electrode, accompanied by an increase in the cell volume, was demonstrated to take place by the formation of a β phase domain in the bulk during the cathodization. The lattice constant was discontinuously changed from a\simeq3.92 to 4.04 Å and such a discontinuous change was observed on the Pd90Au10 alloy as well. However, no phase transformation was observed on the Pd–Au alloys with the Pd content of 70 at.% or below, where the lattice constant increased continuously with an increase in the negative potential for the cathodic polarization. No crystallization in the amorphous Pd–Zr alloy ribbon electrodes was detected after hydrogen charging.
  • Tatsuya Sekine, Hirochika Naganawa
    1989 Volume 62 Issue 2 Pages 419-423
    Published: 1989
    Released: June 27, 2006
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    The spectrum of picric acid in 4-methyl-2-pentanone solutions which contained the acid and water at several concentrations was determined in the wavelength range from 330 to 500 nm and the data were statistically analyzed. It was concluded that picric acid molecules formed ion pairs together with four water molecules in these solutions and the ion pairs thus formed dissociated partially. Both of the ion pairs and dissociated picrate ions in these solutions had strong absorption in the visible range where no absorption was found with the acid molecules but the spectra of these two species were different. The formation and dissociation constants of the ion pairs were also calculated from the data and the role of water in these chemical reactions was considered.
  • Masahiro Taniguchi, Akira Ouchi
    1989 Volume 62 Issue 2 Pages 424-428
    Published: 1989
    Released: June 27, 2006
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    The title complexes have been synthesized and their crystal and molecular structures determined by a single crystal X-ray diffraction technique. [(C2H5)4N][Cd(SCN)3] (1) is orthorhombic with a space group of A21am; a=10.773(2), b=16.574(4), c=9.871(2) Å, and Z=4, while [(C3H7)4N][Cd(SCN)3] (2) is triclinic with a space group of P\bar1; a=10.297(5), b=11.542(5), c=9.374(3) Å, α=90.10(3), β=91.61(4), γ=80.94(4)°, and Z=2. In 1, the metal atom has a 3N,3S-hexa-coordinated octahedral geometry, and three ligated N atoms take fac-configuration. Each pair of a metal atoms are bridged by three thiocyanate (SCN) ions, where two SCN ions are S-coordinated, while the other is N-coordinated to the same side metal atom, forming a linear polymeric form. In 2, the metal atom is in a 3N,2S-penta-coordinated trigonal-bipyramidal geometry, where one non-bridging SCN ion is N-coordinated equatorially, while four bridging SCN ions are ligated with two N (axially), and two S atoms (equatorially), respectively. Each pair of metal atoms is bridged by two SCN ions, forming a linear polymeric form. The respective tetraalkylammonium ions in 1 and 2 are not bridged to the complex anions, but are bonded only electrostatically. The final R values obtained are: 1, 0.042 and 2, 0.052.
  • Shin-ichi Hirano, Kazumi Kato
    1989 Volume 62 Issue 2 Pages 429-434
    Published: 1989
    Released: June 27, 2006
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    Crystalline LiNbxTa1−xO3(0≤x≤1 films were prepared from complex alkoxide solutions, controlling the ratio of Nb to Ta by means of a dip-coating method. The present work revealed the dependence of the film thickness on the concentration of the solution and the speed of the withdrawal of the substrate from the solution, the effects of water on the crystallization of the films, and the effects of the structures of the substrates on the crystallinity of the prepared films.
  • Songping Wan, Wasuke Mori, Shoichiro Yamada, Shun-Ichi Murahashi
    1989 Volume 62 Issue 2 Pages 435-438
    Published: 1989
    Released: June 27, 2006
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    Two types of imino oxime copper(II) complexes were obtained by the reactions of copper(I) halides CuX (X=Br, I) with imino oximes (3-[2-[(alkylamino)ethyl]imino]-2-butanone oximes or 3-[2-[(dialkylamino)ethyl]imino]-2-butanone oximes, abbreviated as Hdox-enRR′). One type contains the binuclear complexes [Cu2(dox-enRR′)2]2+ and uncoordinated halide anions. The magnetic susceptibilities measured over the temperature range 77–320 K show a strong antiferromagnetic spin coupling interaction through the N–O bridge in these complexes. The magnetic behavior can be explained by using the Bleaney–Bowers equation. It is assumed that the complexes of the other type consist of copper(I) and copper(II) in 2:1 ratio without spin-coupling interaction between the copper ions. The plot of the reciprocal magnetic susceptibilities versus temperatures is linear.
  • Shoji Kajigaeshi, Takaaki Kakinami, Masayuki Moriwaki, Toshio Tanaka, ...
    1989 Volume 62 Issue 2 Pages 439-443
    Published: 1989
    Released: June 27, 2006
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    The reaction of arenes with benzyltrimethylammonium tribromide or benzyltrimethylammonium dichloroiodate in acetic acid in the presence of ZnCl2 at room temperature or at 70 °C gave bromo- or iodo-substituted arenes in good yield, respectively.
  • Tadao Shingaki, Hiro Kuma, Yoshihiko Kushi, Toshikazu Nagai
    1989 Volume 62 Issue 2 Pages 444-450
    Published: 1989
    Released: June 27, 2006
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    The title reaction gave 3′,4′-dichloro-1′,6′-dicyanospiro[fluorene]-9,7′-[3′]norcarene]-2′,5′-dione (2) in a good yield. Recrystallizations of 2 from solvents such as benzene, dioxane, acetonitrile, and acetone gave each molecular complex consisting of a 2/solvent molar ratio of 1:1. The structure of 2 was determined by the use of one complex, 2·CH3COCH3, by an X-ray crystallographic analysis, which revealed that an interaction between 2 and acetone was not very strong. Such a host–guest interaction was shown also from 1H NMR spectroscopy and a differential thermal analysis of the complex. Compound 2 afforded the corresponding spiroacetals of 9-fluorenone through reactions with ethylene glycol and 1,3-propanediol.
  • Tomohiro Nagao, Akira Mori, Hitoshi Takeshita
    1989 Volume 62 Issue 2 Pages 451-454
    Published: 1989
    Released: June 27, 2006
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    5-Acetoxytropolone was successfully halogenated by means of benzyltrimethylammonium tribromide and sulfuryl chloride to give 3-halotropolones and 3,7-dihalotropolones which were converted to the corresponding halogenated p-tropoquinone derivatives. From 3,7-dihalo-p-tropoquinones, 3,4,7-trichloro-5-hydroxytropolone was prepared in good yields via a Thiele-type addition reaction with hydrochloric acid. By a similar treatment, 5-hydroxytropolone gave a complex mixture.
  • Shigeru Ishii, Hidenobu Nakayama, Yasuhiko Yoshida, Tadataka Yamashita
    1989 Volume 62 Issue 2 Pages 455-458
    Published: 1989
    Released: June 27, 2006
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    Carbon dioxide reacted with aliphatic amines and ortho esters to form carbamic esters in good yields. The influence of different ortho esters on the carbamate synthetic reaction is described. In the case of orthocarbonates, carbamic esters were obtained in high yields. The reaction of carbon dioxide, amines, and ortho esters may involve a competitive reaction between the esterification of carbamic acid produced by a reaction of carbon dioxide with amine, and the alkylation of amine.
  • Keiji Okada, Seiji Tomita, Masaji Oda
    1989 Volume 62 Issue 2 Pages 459-468
    Published: 1989
    Released: June 27, 2006
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    Stereoselectivity in the metal hydride reduction of a series of substituted 1,2,3,4-tetrahydro-1,4-methanonaphthalen-9-ones was investigated in relation to their homoconjugation character. The observed stereoselectivity sequence was found to be parallel with the homoconjugation sequence: the portion of anti-attack increases as the benzene ring becomes electron-rich. The results are rationalized in terms of the transition state model proposed by Cieplak or of the contribution of the nonclassical carbocation in the transition state.
  • Munehiro Nakatani, Shuichi Hatanaka, Hajime Komura, Takashi Kubota, Ts ...
    1989 Volume 62 Issue 2 Pages 469-473
    Published: 1989
    Released: June 27, 2006
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    A new bitter triterpene ester glucoside have been isolated along with known bitter triterpene glucoside peduncloside and some minor triterpenes ulsolic acid, rotundic acid, and rotungenic acid from the unripe fruits of Ilex rotunda. The structure was characterized as β-D-glucopyranosyl 3β,19α,24-trihydroxyurs-12-en-28-oate by spectral data and chemical means.
  • Yoichi Taguchi, Masahiko Yasumoto, Isao Shibuya, Yasuo Suhara
    1989 Volume 62 Issue 2 Pages 474-478
    Published: 1989
    Released: June 27, 2006
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    An equimolar reaction of 2-hexyloxirane with carbon disulfide in hexane was run in the presence of triethylamine under 800 MPa at 100 °C for 20 h, and gave 63% of 4-hexyl-1,3-dithiolan-2-one (3a), 21% of 4-hexyl-1,3-dithiolane-2-thione (1a) and 5% of 5-hexyl-1,3-oxathiolan-2-one (4a). Hexane, benzene, and diisopropyl ether were good solvents for the reaction. The reaction of a variety of oxiranes with carbon disulfide produced 1,3-dithiolan-2-ones as the main products under 500 MPa at 100 °C for 20 h. Upon a reaction of 2-hexyloxirane with carbon disulfide, 5-hexyl-1,3-oxathiolane-2-thione (2a), and 2-hexylthiirane (5a) were produced during the first stage of reaction. The formation of 1a and 4a began immediately, whereas, the formation of 3a required a long induced period. A feasible mechanism for the formation of 3a is proposed to be a rearrangement of 2a in the presence of triethylamine, free from carbon disulfide.
  • Yohsuke Yamamoto, Kin-ya Akiba
    1989 Volume 62 Issue 2 Pages 479-484
    Published: 1989
    Released: June 27, 2006
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    The existence of ring transformation equilibrium (bond switch) in 5-(1-aminoethylideneamino)-3-methyl-1,2,4-thiadiazole (5a) was confirmed by nitrogen-15 labeling experiment. Kinetic studies were carried out under neutral or acidic conditions. Kinetic parameters of the intramolecular equilibration of the monoprotonated 5a (5a-H+) were obtained by line shape analyses of the 1H NMR, i.e., ΔG273\ eweq=14.8±0.2, ΔH\ eweq=11.6±1.0 kcal·mol−1 ΔS\ eweq=−12±3 eu, k273=9 s−1. Position of protonation was determined at the nitrogen of the ethylideneamino part of the amidino group. It was concluded that the central sulfur atom moves back and forth in the range of 0.38 Å nine times a second at 0 °C, that is, bond switching.
  • Kazuhiro Moriyama, Mikio Nakamura, Nobuo Nakamura, Michinori Oki
    1989 Volume 62 Issue 2 Pages 485-489
    Published: 1989
    Released: June 27, 2006
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    Deprotonation of 9-(2-substituted 1-naphthyl)fluorene rotamers, where the substituent is a dimethylamino, a methoxy, or a methylthio, has been carried out with butyllithium in hexane–benzene. While the reactions of the ap-isomers were generally slower than those of the sp-isomers, the difference in the methoxy compounds was the greatest among the compounds examined. The results are discussed on the basis of the ease of ligation of the substituent and the steric effects that prevail in the ap-isomers, together with the distance between 9-position and the ligation site in the subsituent.
  • Kuniaki Tatsuta, Jun Hayakawa, Yukio Tatsuzawa
    1989 Volume 62 Issue 2 Pages 490-492
    Published: 1989
    Released: June 27, 2006
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    2-Deoxy-β-arabino- and ribopyranosyl cyanides, which should be suitable for the syntheses of biologically active products, were stereoselectively prepared from the reaction of the enones, 1,5-anhydro-2-deoxy-erythro-hex-1-en-3-ulose derivatives, with acetone cyanohydrin, followed by the stereoselective reduction of the producing ketones with NaBH4–CeCl3·7H2O and L-Selectride, respectively.
  • Jihong Wu, Masaki Funakoshi, Hidetoshi Nagamoto, Hiroshi Komiyama, Hak ...
    1989 Volume 62 Issue 2 Pages 493-498
    Published: 1989
    Released: June 27, 2006
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    Pd/TiO2 catalysts prepared by different methods showed quite different catalytic activities in the hydrogenation of CO and other unsaturated compounds. The catalyst prepared by coprecipitation of Pd acetate and titanium tetraisopropoxide contained smaller Pd particles than those in catalysts prepared by impregnation methods. In the hydrogenation of CO, activities of the catalysts increased with increase in the Pd dispersion. The coprecipitated catalyst was much more active for this reaction than the other catalysts and showed high activity for methanol formation under normal pressure. In the hydrogenation of propionaldehyde to 1-propanol, the catalysts showed similar behavior to that in the CO/H2 reaction. However, in hydrogenation of C=C double bonds, the activity order of the catalysts was reverse. Higher activity was obtained on the impregnated catalysts with larger Pd particle size and this trend was stronger in hydrogenation of the conjugated butadiene and C=C bond in acrylaldehyde than in the hydrogenation of ethvlene.
  • Kensaku Morihara, Eiko Tanaka, Yuko Takeuchi, Kazue Miyazaki, Nami Yam ...
    1989 Volume 62 Issue 2 Pages 499-505
    Published: 1989
    Released: June 27, 2006
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    A tailor-made catalyst design was attempted for a required substrate specificity by the authors’ footprint imprinting method. Two silica(alumina) footprint catalysts were prepared by imprinting with N-benzoylbenzenesulfonamide (1) and N-(p-toluoyl)-p-toluenesulfonamide (2) from the same aluminum ion-doped silica gel. Their catalytic effects upon 2,4-dinitrophenolysis of benzoic anhydride, p-, m-, and o-toluic anhydrides were compared in order to find any difference in substrate specificities. The catalyst prepared by imprinting with 1 showed the largest specificity(kcatKm) toward benzoic anhydride, whereas the catalyst prepared with 2 showed the largest specificity toward p-toluic anhydride. This finding evidently demonstrated that the substrate specificities of footprint catalytic sites are alterable, as required through selecting appropriate transition state analogs as template molecules for footprint marking.
  • Guan Rong Tian, Akira Mori, Nobuo Kato, Hitoshi Takeshita
    1989 Volume 62 Issue 2 Pages 506-513
    Published: 1989
    Released: June 27, 2006
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    Photocycloaddition of exo,endo-2,7-bis(methoxycarbonyl)-11,12-dioxatetracyclo[6.2.1.13,6.02,7]dodeca-4,9-diene with conjugated enones and p-quinones occurred exclusively at the exo-addition moiety to give [2+2]cycloadducts. From cyclohexenone, all four possible photoadducts were obtained. A single photoadduct from cyclopentenone was a cis-transoid-cis isomer. Upon thermolysis, cyclobutene derivatives were formed from these photoadducts. An acid treatment of oxetane derivatives derived from photoadducts of p-quinones afforded Michael adducts instead of dienone–phenol rearrangement products.
  • Shigeru Kunugi, Kazuo Tanabe, Kouji Yamashita, Yoshio Morikawa, Takano ...
    1989 Volume 62 Issue 2 Pages 514-518
    Published: 1989
    Released: June 27, 2006
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    The effect of high pressure on peptide formation by the catalysis of carboxypeptidase Y (substitution of ester or peptide by amino acid derivative) or by thermolysin (condensation of N-acylamino acid and amino acid amide) was studied. The carboxypeptidase Y-catalyzed substitution reaction of N-[3-(2-furyl)acryloyl]phenylalanine ethyl ester with glycinamide or phenylalaninamide showed a six-fold higher total peptide yield at 200 MPa than at atmospheric pressure. In the case of the reaction of N-acyldipeptide and amino acid amide, both the peptide yield and substitution efficiency were improved at elevated pressure and the wasteful hydrolysis of the substrate was highly depressed by increasing pressure. The pressure was also effective to get rid of the substrate inhibition by the amino acid ester in the reaction between the N-acylamino acid ester and the amino acid ester and to yield much dipeptide ester at high pressure. An improvement of the peptide yield by pressure for the reaction of thermolysin was observed in a combination of less specific substrates, N-benzyloxycarbonyl-L-aspartic acid and phenylalanine methyl ester, since the high catalytic activity of this enzyme under elevated pressure was significant only in the case that the peptide yield was kinetic-controlled.
  • Shigekazu Kanemoto, Hiroyuki Saimoto, Koichiro Oshima, Kiitiro Utimoto ...
    1989 Volume 62 Issue 2 Pages 519-523
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Several polymer supported catalysts are prepared by treatment of Nafion®551 (abbreviated NAFK below) with metal salts. Cr/NAFK and Ce/NAFK are found to be effective catalysts for the dehydrogenative oxidation of alcohols to the corresponding ketones by means of t-butyl hydroperoxide. Selective oxidation of secondary alcohols in the presence of primary ones was performed using a Ce/NAFK–NaBrO3 system.
  • Saburo Aimoto, Noriko Mizoguchi, Hironobu Hojo, Shoko Yoshimura
    1989 Volume 62 Issue 2 Pages 524-531
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A new method for the preparation of pure polypeptides based on the minimun-protection strategy is described. Its effectiveness was demonstrated by a synthesis of bovine pancreatic trypsin inhibitor (BPTI). Protected peptide segments of Z-[Arg(Tos)1, Asp(OcHex)3, Cys(Acm)5, Glu(OcHex)7]-BPTI(1–13), Boc-[Cys(Acm)14,30, Lys(Z)15,26]-BPTI(14–36), and [Cys(Acm)38,51,55, Lys(Z)41,46]-BPTI(37–58) were prepared by modifying the products obtained by solid-phase peptide syntheses. The protected peptides corresponding to BPTI(14–36) and BPTI(37–58) were coupled by an active ester method to give protected BPTI(14–58). Next, protected BPTI(1–13) was coupled to the BPTI(14–58) by an active ester method after removing the Boc group from the protected BPTI(14–58). All of the protecting groups on BPTI(1–58) were removed, and the resulting peptide was oxidized to give the native form of BPTI in a very pure form. The synthetic BPTI was shown to be identical with the native BPTI in an elution experiment on ion-exchange chromatography and in its inhibitory activity. The new method proved to be very effective for a rapid preparation of pure polypeptide.
  • Sadao Sato, Masaru Sato, Sadatoshi Akabori
    1989 Volume 62 Issue 2 Pages 532-538
    Published: 1989
    Released: June 27, 2006
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    The structures of 1:1 complexes (3b, 4b, and 5b) of 1.4,7,10,13-pentaoxa-, 1,13-dioxa-4,7,10-trithia[13]- and 1,4,7,10,13,16-hexaoxa[16](1,1′)ruthenocenophanes (3a, 4a, and 5a) with HgCl2, and 3a have been determined by the single-crystal X-ray diffraction method. The complexing forms of the three complexes are quite similar to each other. Crystal data: 3b, triclinic, space group P\bar1, a=12.043(3), b=10.759(2), c=8.529(2) Å, α=98.76(2), β=101.22(2), γ=77.03(2)°, U=1049.5 Å3, Z=2, Dc=2.19 g cm−3, μ(Mo Kα)=84 cm−1. 4b, triclinic, space group P\bar1 a=17.100(3), b=8.986(1), c=8.618(2) Å, α=105.17(1), β=62.24(1), γ=100.54(1)°, U=1128.1 Å3, Z=2, Dc=2.18 g cm−3, μ(Mo Kα)=81 cm−1. 5b, monoclinic, a space group P21a, a=26.881(7), b=10.344(3), c=8.414(2), β=96.97(2)°, U=2322.2 Å3, Z=4, Dc=2.11 g cm−3, μ(Mo Kα)=76 cm−1. 3a, triclinic, space group P\bar1, a=11.107(1), b=8.816(1), c=9.788(1) Å, α=70.48(1), β=99.76(1), γ=101.31(1)°, U=877.6(2) Å3, Z=2, Dc=1.59 g cm−3, μ(Mo Kα)=9 cm−1. Only the Ru atom of the ruthenocene nucleus of these complexes was coordinated to HgCl2 with a slightly distorted trigonal-planar configuration. The distances between the Ru and the Hg atoms are 2.683(3), 2.704(1), and 2.696(2) Å, respectively.
  • Yasuo Saegusa, Tatsushi Watanabe, Shigeo Nakamura
    1989 Volume 62 Issue 2 Pages 539-544
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A novel condensing agent, 3,3′-carbonylbis[5-phenyl-1,3,4-oxadiazole-2(3H)-thione] (3), was readily prepared by the reaction of 5-phenyl-1,3,4-oxadiazole-2(3H)-thione with trichloromethyl chloroformate in benzene. The reagent 3 was found to be very useful for the one-pot or direct preparation of amide, ester, thiol ester, urea, and carbonate under mild conditions. The one-pot or direct polycondensation of several dicarboxylic acids with aromatic diamines and of aromatic diamines using 3 proceeded smoothly at ambient temperature to produce high-molecular-weight polyamides and polyureas, respectively.
  • Hiroshi Nishino, Katsunori Tsunoda, Kazu Kurosawa
    1989 Volume 62 Issue 2 Pages 545-550
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The reaction of naphthalenes with malonic acid in the presence of manganese(III) acetate gives naphthalenecarbaldehydes and naphthalenecarboxylic acids. Similar reactions of anthracene, pyrene, and methoxybenzenes also yield formylated and carboxylated products. It was found that the formyl group introduced to the aromatic ring was not derived from carboxymethyl radical generated directly by the thermolysis of manganese(III) acetate, but from a dicarboxymethyl radical formed by the interaction of malonic acid and manganese(III) acetate. In addition, it was also found that the dicarboxymethyl radicals attacked the position of the highest electron density on the aromatic ring and that this formylation was effective when the ionization potential of the aromatic compound was lower than 7.8 eV.
  • Yoshiharu Nakamura, Noriaki Kamon, Teruo Hori
    1989 Volume 62 Issue 2 Pages 551-556
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    To realize artificially such a conjugated redox reaction as that which is drived across the biological cell membrane, two enzymic redox reactions were conjugated across a hydrogel membrane prepared with urethane prepolymer holding stabilized isocyanate groups. As redox couples, glucose 6-phosphate (G6P)/glucose 6-phosphate dehydrogenase (G6PD)/gluconolactone 6-phosphate (GL6P) and glutathione oxidized form (GSSG)/glutathione reductase (GRD)/glutathione reduced form (GSH) were chosen together with their common coenzyme, NADP+/NADPH. The driving of a system consisting of two redox couples separated with the hydrogel membrane containing the coenzyme NADP+ was intiated by the reduction of NADP+ on the membrane surface in contact with the G6PD/G6P solution. The conjugated redox reaction proceeded by electron exchange between coenzymes in the membrane and the reproducing of NADP+, which was accompanied with the GRD/GSSG solution. The rate of electron transfer across the urethane membrane was markedly accelerated by incorporating a nonkeratinous intercellular cement compound extracted from wool into the membrane. From cyclic voltammograms of a methyl viologen mediator, using a bare electrode and an intercellular compound modified carbon electrode, it was confirmed that the intercellular component could surely act as a good electron carrier.
  • Masatoshi Nagai, Hideo Urimoto, Kazuya Uetake, Noriyuki Sakikawa, Rich ...
    1989 Volume 62 Issue 2 Pages 557-562
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The mechanism of the desulfurization of the polynuclear thiophene compounds with a Raney nickel was studied in ethanol at atmospheric pressure and from 0 to 78.3 °C. The desulfurization rate was initially fast but reached zero in about 30 minutes. The major products were biphenyl in the desulfurization of dibenzothiophene (1), 1-phenylnaphthalene in the desulfurization of benzo[b]naphtho[1,2-d]thiophene (2), and 2-phenylnaphthalene in the reaction of benzo[b]naphtho[2,3-d]thiophene (3) and benzo[b]naphtho[2,1-d]thiophene (4). The desulfurization extent for the four compounds decreased in this sequence: 3>1>2>4. The extent of the desulfurization of the polynuclear thiophene compound was not related to the reaction indices, Fr(E), Fr(N), and Fr(R), of the sulfur atom of the compounds, which were calculated by using a simple Hückel theory; rather, it was related to both the free valence and the π-electron density. Therefore, the polynuclear thiophene compounds were considered to adsorb on a Raney nickel through the free-electron pair of the sulfur atom; consequently, the adsorption led to the C–S bond scission.
  • Naoki Toshima, Hiroyuki Asanuma, Kazuaki Yamaguchi, Hidefumi Hirai
    1989 Volume 62 Issue 2 Pages 563-570
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Aqueous dispersions of the chelate resin–iron(II) complex were prepared by ion-exchange in water from iron(II) sulfate and a chelate resin containing iminodiacetic acid moieties. The resulting dispersions in water (50 cm3) can adsorb 78% of the nitrogen oxide (NO) from 6 dm3 of nitrogen gas containing 1000 ppm of nitrogen oxide at 25 °C. The adsorption rate of NO by the dispersions depends greatly on both the particle size of the chelate resin used and the concentration of iron(II) in the supernatant. A fast adsorption of nitrogen oxide can be achieved by using small particles of the chelate resin and by dissolving a large amount of iron(II) ions in the aqueous part of the dispersions. The adsorption and desorption of nitrogen oxide can be understood in terms of a 1:1 reversible coordination of NO to the iron(II) ion immobilized on the chelate resin. The equilibrium constant, enthalpy change, and entropy change for the above adsorbing reaction were 3.11×104 dm3 mol−1, −45.6 kJ mol−1, and −68.2 J K−1 mol−1 respectively. Since the adsorbing reaction of NO in this system is reversible, the adsorbed NO can be released by heating the dispersions which have already adsorbed NO. The amount of the released NO can be predicted from the equilibrium constant at the releasing temperature. Moreover, a concentrated recovery of the NO can be achieved by the present aqueous dispersions system.
  • Katsumaro Minamoto, Niro Shiomi, Kazumoto Kondo, Shoji Eguchi, Masako ...
    1989 Volume 62 Issue 2 Pages 571-573
    Published: 1989
    Released: June 27, 2006
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    The crystal structure of 8,5′-[(allylimino)carbonyloxy]-2-N-dimethylaminomethylene-9-(2′,3′-O-isopropylidene-β-D-ribofuranosyl)guanine (2a) methanol solvate was determined by X-ray analysis. Its base-sugar torsion angle conforms to the CD spectral behavior of the partially deprotected compound 2b in the sense of anti-conformation.
  • Hisashi Uedaira, Miyuki Ishimura
    1989 Volume 62 Issue 2 Pages 574-575
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Values of the relative increment of the sound velocity, A, in aqueous solutions of sugars were calculated from the experimental sound velocities. The values of A correlated well with the mean number of equatorial OH groups in a sugar molecule.
  • Takayuki Kobayashi
    1989 Volume 62 Issue 2 Pages 576-577
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The anomalous charge states formed after the EC decay of 57Co in FeSO4·7H2O doped with 57Co are investigated in detail using the gamma-X ray coincidence Mössbauer spectroscopy. The mechanism to form these states is explained in terms of the H2O and SO42− coordination shells around the decaying atom.
  • Kenji Ikeda, Tomoko Nakasima, Kunio Esumi, Kenjiro Meguro
    1989 Volume 62 Issue 2 Pages 578-580
    Published: 1989
    Released: June 27, 2006
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    The critical micelle concentrations of a α,ω-type surfactant: (sodium α,ω-alkanediyl disulfate: n=12, 14, 16) in an aqueous solution have been determined by studying the electrical conductivity, and the free energies of the micelle formation have then been estimated from these data. The free energy of micelle formation of a α,ω-type surfactant was smaller than that of a normal-type surfactant with the same alkyl chain length as the α,ω-type one. The free-energy changes per –(CH2)– segment was also calculated from these data. It is found that the free-energy change per –(CH2)–segment of the α,ω-type surfactant is −11.1 [kJ mol−1].
  • Hirotaka Hirata, Yuko Sakaiguchi
    1989 Volume 62 Issue 2 Pages 581-582
    Published: 1989
    Released: June 27, 2006
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    In a system of hexadecyltrimethylammonium bromide (HTAB)–salicylic acid (SA) in which a remarkable viscoelasticity is induced, we noticed the existence of single crystals coimaged with the infinitely elongated rod-like micelles. The single crystal implied the formation of a new species, a complex which resulted from the interaction of HTAB and aromatic additives.
  • Masakazu Iwamoto, Hidenori Yahiro, Takashi Kutsuno, Sukehiro Bunyu, Sh ...
    1989 Volume 62 Issue 2 Pages 583-584
    Published: 1989
    Released: June 27, 2006
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    Catalytic activity of Y zeolites containing copper ions (CuY) for decomposition of nitrogen monoxide was enhanced through additional exchange of other metal ions or evacuation treatment around 923–973 K. In the first case, Co3+ or Ni2+ ions increase the catalytic activity while Ca2+, Mn2+, Fe2+, and Zn2+ diminish the catalytic activity of CuY. In the second case, the catalytic activity of CuY evacuated at 973 K was twice that of CuY without the evacuation treatment, which is discussed in connection with the increment of Cu ions active for the decomposition.
  • Takumi Konno, Sen-ichi Aizawa, Jinsai Hidaka
    1989 Volume 62 Issue 2 Pages 585-587
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Three kinds of S-bridged trinuclear complexes, ΔLLLΔLLL-[Co3(L-cys-N,S)6]3−, ΔLLLΔ- and ΔLLLΛ-[Co3(L-cys-N,S)3(aet)3]0, and [Co3(aet)6]3+, were formed by the reaction of a mixture of ΔLLL-fac-[Co(L-cys-N,S)3]3− (L-cys=L-cysteinate) and fac-[Co(aet)3] (aet=2-aminoethanethiolate) with [CoCl(NH3)5]2+. The reaction with an excess amount of Co2+ led to the formation of seven kinds of S-bridged complexes, [Co3(L-cys-N,S)n(aet)6−n]3−n](n=0–6).
  • Kazuma Oguni, Tomoji Ohishi, Masakazu Kita, Kazuo Kashiwabara, Junnosu ...
    1989 Volume 62 Issue 2 Pages 588-590
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Ligand field irradiation of cis-[CoCl2{(CH3)2PCH2CH2CH2P(CH3)2}2]+ in methanol and cis-[CoCl(H2O){(CH3)2PCH2CH2P(CH3)2}2]2+ in acetonitrile at 5 °C led to isomerization to the trans isomer with quantum yields of 0.010 and 0.070, respectively. The same cis to trans photoisomerization of [CoCl2(R2PCH2CH2PR2)2]+ (R=CH3, C4H9) occurred with much smaller quantum yields (ca. 1×10−4) and cis-[CoCl2{(C6H5)2PCHCHP(C6H5)2}2]+ was reduced to cobalt(II) species on irradiation.
  • Hisatoshi Konishi, Katsutomo Aritomi, Tamon Okano, Jitsuo Kiji
    1989 Volume 62 Issue 2 Pages 591-593
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The monobromination of alkoxybenzenes with N-bromosuccinimide catalyzed by silica gel in carbon tetrachloride occurred preferentially at the para-position. m-t-Butylmethoxybenzene yielded 4-bromo-3-t-butyl-1-methoxybenzene with a selectivity of 74% even in the presence of a bulky substituent at the meta-position.
  • Makoto Tamaki, Michiaki Takimoto, Mitsuo Hayashi, Ichiro Muramatsu
    1989 Volume 62 Issue 2 Pages 594-596
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Four pentapeptide N-hydroxysuccinimide esters [X–Orn(Z)–Leu–Y–Pro–ONSu (X=Val or D-Val, and Y=Phe or D-Phe)] related to gramicidin S were allowed to cyclize in pyridine. The peptides with a L-Phe residue preceding Pro tend to form various cyclic polymers, while ones with a D-Phe residue exclusively yielded a cyclic monomer or cyclic dimer. Peptides with a D-Val residue at the N-terminal produced monomerization products. The observed tendencies were similar for cyclization of four hexapeptide N-hydroxysuccinimide esters [X–Val–Orn(Z)–Leu–Y–Pro–ONSu (X=Tyr(Bzl) or D-Tyr(BzlCl2), and Y= Phe or D-Phe)] related to gratisin.
  • Takashi Iizawa, Akira Goto, Tadatomi Nishikubo
    1989 Volume 62 Issue 2 Pages 597-598
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Regioselective addition reactions of 2-substituted oxiranes with S-phenyl thioesters gave 2-aceyloxy-1-phenylthio derivatives in high yield using some 18-crown-6–metal complexes as well as tetrabutylammonium salts as a catalyst under relatively mild conditions.
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