Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 67 , Issue 9
Showing 1-50 articles out of 52 articles from the selected issue
  • Masaru Kimura, Ikuko Miyamoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2357-2360
    Published: 1994
    Released: July 28, 2006
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    The oxidation reaction of the cobalt(II) complex [Co(edta)]2− to [Co(edta)] (edta4− = ethylenediaminetetraacetate ion) occurred efficiently by hydrogen peroxide or peroxodisulfate with activated carbon (AC) in aqueous media of pH 4.7, where the AC acts as a catalyst of the electron-transfer mediator. The oxidation reaction constitutes a chain reaction comprising the AC/AC+ cycle, in which the oxidation reaction is initiated by an electron-transfer from AC to hydrogen peroxide or peroxodisulfate to make radicals of AC+ and OH, or SO4−•. These radicals could rapidly oxidize [Co(edta)]2− to [Co(edta)]. The rate of the oxidation reaction is of first-order with respect to the concentrations of hydrogen peroxide (or peroxodisulfate) and the AC amounts added, and of zero-order to [Co(edta)]2− under the conditions. Further, the rate was unrelated to the dissolved O2. In the case of hydrogen peroxide, it could be decomposed by the AC, even in the absence of [Co(edta)]2−, according to the first-order with respect to the hydrogen peroxide concentration; the rate constant was 2-fold of the rate constant in the presence of [Co(edta)]2−. However, in the case of peroxodisulfate, no appreciable decomposition of the S2O82− was found in the absence of [Co(edta)]2−, and the decomposition rate in the presence of [Co(edta)]2− was 104-fold faster than the rate of hydrogen peroxide decomposition under the same conditions. Consequently, it is concluded that the AC acts in a way similar to iron(II) ion in the Fenton-reagent.
  • Yôichi Iida
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2361-2367
    Published: 1994
    Released: July 28, 2006
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    The signals which direct excision of introns from mRNA precursors in mammalian genes have been studied. The consensus sequence for the 3′-splice site is (T or C)11N(C or T) AG/G, where N is A, G, C or T, and where the stroke (/) indicates the boundary between intron and exon. In the present research, the nucleotide sequence at the 3′-splice junction in rabbit β-globin gene was analyzed by a quantification method proposed previously. Using a sample score of 16-nucleotide sequence at the 3′-splice junction, we proposed the strength of the 3′-splice signal. This approach could explain not only the location of the authentic 3′-splice sites in rabbit β-globin pre-mRNA but also the experimental results of various point mutations introduced into the 3′-splice region of the second intron. Our analysis also explains a skipping mechanism of the second exon, in which the first exon is spliced directly to the third exon if the 5′-splice site of the second intron is destroyed.
  • Yohji Misaki, Hiroyuki Nishikawa, Tokio Yamabe, Takehiko Mori, Hiroo I ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2368-2372
    Published: 1994
    Released: July 28, 2006
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    The molecular and crystal structures of the title compounds, where TMEO-TTP is 2-[4,5-bis(methylthio)1,3-dithiol-2-ylidene]-5-[4,5-ethylenedioxy-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalene, have been investigated by X-ray crystal structure analysis. The BDT-TTP skeleton of neutral TMEO-TTP adopts a slightly flat chair conformation. The crystal has a columnar structure, in which the molecules dimerize in a head-to-tail manner. Several S···S contacts shorter than the sum of the van der Waals radii (3.70 Å) are observed along the transverse direction. (TMEO-TTP)[AuBr2]·THF also has a columnar structure in which the donor molecules dimerize. However, “side-by-side” interaction between the donors is prohibited because the AuBr2 anions and the THF molecules are located at the sides of the donor molecules.
  • Atsushi Kajiwara, Hiroyuki Sugimoto, Mikiharu Kamachi
    1994 Volume 67 Issue 9 Pages 2373-2377
    Published: 1994
    Released: July 28, 2006
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    Structures of 4-methacryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (MOTMP) and 4-acryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (AOTMP) which have one-dimensional ferromagnetic coupling and antiferromagnetic interactions, respectively, have been determined by X-ray crystallographic analysis. The crystals of both compounds are monoclinic and have space group P21 (No. 4) with Z = 2. The one-dimensional ordering of spins of NO radicals is explained by intermolecular superexchange interactions of NO radicals due to NO radical ···C=C–C=O···NO radical contacts shorter than the van der Waals radii sum (ca. 3.6 Å). The difference in magnetic behavior between MOTMP and AOTMP might be due to the difference in the torsion angle of the C=C–C=O moiety, as in the three-dimensional molecular arrangement in the crystals.
  • Fudeko Tanaka, Yuzo Harada, Norihiro Ikeda, Makoto Aratono, Kinsi Moto ...
    1994 Volume 67 Issue 9 Pages 2378-2382
    Published: 1994
    Released: July 28, 2006
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    The surface tension of the aqueous solution of sodium 4′-(butylamino)azobenzene-4-sulfonate (SBAS) and octyl methyl sulfoxide (OMS) mixture was measured as a function of the total molality at various compositions and at 298.15 K under atmospheric pressure. The experimental results were analyzed by applying the thermodynamic relations. The phase diagrams of adsorption and micelle formation were found to suggest that SBAS and OMS molecules interact attractively with each other to form a negative azeotropic mixture in the adsorbed film at a low surface tension and in the micelle. These findings were qualitatively similar to those of the system of SBAS and 2-(octylsulfinyl)ethanol (OSE) and confirmed our conclusion that the strong interaction of dye and nonionic surfactant molecules at the interface may be the one of reasons why a nonionic surfactant acts as the leveling agent in dyeing process.
  • Daisuke Hashizume, Yuji Ohashi, Koichi Tanaka, Fumio Toda
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2383-2387
    Published: 1994
    Released: July 28, 2006
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    The achiral molecules of N-(arylcarbonylmethyl)-2-piperidones form 1 : 1 host–guest complexes with the chiral host molecule derived from tartaric acid. The guest molecules in the clathrate crystals are converted into the chiral 7-aryl-7-hydroxy-1-azabicyclo[4.2.0]octan-2-one derivatives with high optical yields on exposure to a high pressure Hg lamp. The crystal structures and absolute configurations of the clathrate compound (5a), which consists of (−)-(2R,3R)-2,3-bis(hydroxydiphenylmethyl)-1,4-dioxaspiro[4.5]decane (4) and N-(p-bromophenylcarbonylmethyl)-2-piperidone (1a), and of the chiral product of (−)-(6S,7S)-7-hydroxy-1-azabicyclo[4.2.0]octan-2-one (2a) were determined by X-rays. (5a) C34H34O4·C13H14NO2Br, fw = 802.81, monoclinic C2, a = 24.186(3), b = 9.550(3), c = 19.711(3) Å, β=116.18(1)°,V = 4086(2) Å3, Z = 4, final R became 0.047. (2a) C13H14NO2Br, fw = 296.16, orthorhombic, P212121, a = 7.047(2), b = 31.151(3), c = 5.696(2) Å, V = 1250.3(5) Å3, Z = 4, final R became 0.039. The enantioselectivity of the photocyclization is clearly explained by the two structures if we assume that the reaction proceeds topochemically.
  • Omar Ahmed, Yoshimi Sueishi, Norio Nishimura, Shunzo Yamamoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2388-2392
    Published: 1994
    Released: July 28, 2006
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    The cadmium photosensitized luminescence of some compounds containing three donor atoms (N and/or O) has been investigated by the steady illumination method at temperatures between 453 and 553 K. Broad emission spectra in the visible region were observed with diethylenetriamine (DETA), dipropylenetriamine (DPTA), bis(2-methoxyethyl) ether (BMOEE), bis-2-methoxyethylamine (BMOEA), and bis-(dimethylaminoethyl) ether (BDAEE). By comparing each of these spectra with the spectra of the corresponding bifunctional compounds, we can resolved these spectra into three component bands for DETA, DPTA, BMOEE, and BMOEA, and into four component bands for BDAEE. The longest wavelength bands were observed for the first time. They can be assigned to different types of 1 : 1 exciplexes (acyclic, monocyclic, and bicyclic). The enthalpy changes of the chelations were evaluated from the temperature dependences of the intensities of the bands and were found to depend on the type of chelating atom.
  • Yoshikata Koga, Toshiaki Tanaka, Tooru Atake, Peter Westh, Aase Hvidt
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2393-2397
    Published: 1994
    Released: July 28, 2006
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    Liquid–solid phase diagram was determined in the water-rich region of aqueous 2-butoxyethanol. A solid addition compound was suggested with the composition = 0.0260, which melts incongruently at 269.5 K. The mixing scheme boundary separating two regions in the single liquid phase domain (Chem. Phys. Lett., 217, 245 (1994)) was found to cross the incongruent melting point of the above solid addition compound.
  • Shigeyoshi Miyagishi, Hirotaka Kurimoto, Yuuhichi Ishihara, Tsuyoshi A ...
    1994 Volume 67 Issue 9 Pages 2398-2402
    Published: 1994
    Released: July 28, 2006
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    A new method based on the fluorescence intensity of bis[4-(dimethylamino)phenyl]methanimine (auramine) was proposed in order to determine the critical micelle concentration (cmc). The cmc values of the following surfactants were determined by the present method, and were compared with those by a surface-tension method. The nonionic surfactants used were homogeneous polyethylene glycol monododecyl ether (C12E5, C12E6, C12E7, and C12E8) and N-acyl-N-methylglucamine (MEGA-7, -8, -9, -10, and -12). The cationic surfactants were dodecyltrimethylammonium chloride and bromide (DTAC, DTAB), tetradecyltrimethylammonium bromide (TTAB), hexadecyltrimethylammonium chloride and bromide (CTAC, CTAB). The potassium salt of N-acylalanines, the sodium salt of N-acylvalines, and sodium dodecyl sulfate were used as anionic surfactants. The cmcs measured by both methods were in good agreement with each other in all systems of surfactants used. The effects of added salt, temperature, and size of the acyl group on the microviscosity were also estimated.
  • Elaheh K. Goharshadi, Ali Boushehri
    1994 Volume 67 Issue 9 Pages 2403-2406
    Published: 1994
    Released: July 28, 2006
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    Intermolecular pair-potential energy functions are given for all the unlike interactions of Ar, Kr, and Xe. The potentials are determined by direct inversion of experimental reduced viscosity collision integrals obtained from the corresponding-states correlation. The results are in good agreement with the potentials proposed by Ron Aziz.
  • Takayuki Miyamae, Masaaki Shimizu, Jiro Tanaka
    1994 Volume 67 Issue 9 Pages 2407-2416
    Published: 1994
    Released: July 28, 2006
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    Polarized reflection spectra of a highly oriented new type polyacetylene doped with perchlorate are presented. From the reflection spectra, measured from far infrared to ultraviolet regions, the optical conductivity spectra are obtained by Kramers–Kronig analysis. Three stages of doping are recognized from a spectral analysis. (1) 0 < y < 0.02, where the charged soliton band is dominant; (2) 0.02 < y < 0.04, the spectra change completely and the polson band begins to grow; (3) 0.045 < y, the spectral characteristic of metallic phase appears. Three-dimensional interaction of the polson chain is found to be essential for appearance of metallic conductivity. The origin of metallic properties is discussed from the change of spectra at different dopant concentration. The effect of orientation of polyacetylene chain on the spectra is discussed.
  • Mohamed A. El-Gahami
    1994 Volume 67 Issue 9 Pages 2417-2419
    Published: 1994
    Released: July 28, 2006
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    Coordination polymers of [(8-hydroxy-5-quinolyl)imino]mercaptoacetic acid have been prepared with the metal ions, Cu2+, Ni2+, Co2+, Cd2+, and Hg2+. The polymeric complexes have been characterized by elemental analyses, TGA, molar conductance as well as electronic and IR spectral measurements. It was found that the ligand behaves as a triprotic tetradentate one. The coordination takes place through the oxygen and nitrogen atoms of the quinolinol moiety as well as through the mercapto and carboxyl groups of the mercaptoacetic acid. The analytical data depict the formation of complex compounds with the stoichiometry 3 : 2 (metal : ligand). Tetrahedral stereochemical configuration is suggested for these polymeric complexes.
  • Anjali Pal
    1994 Volume 67 Issue 9 Pages 2420-2423
    Published: 1994
    Released: July 28, 2006
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    A method for the determination of trichloroacetic acid (TCA) in a simple spectrophotometric way has been described. It is based on the photochemical reaction of TCA with diphenylamine (DPA) which forms a green colored product (λmax: 652 nm). The relative standard deviation for all measurements is <7%. A linear calibration graph is obtained in the concentration range of 610 to 2875 ppm with a correlation coefficient 0.990. The method is simple, rapid and does not require any costly and hazardous chemical. The effect of solvent, reagent concentration, time of irradiation etc. have been discussed. Extraction of TCA from contaminated water or urine with upto 10 fold increase in concentration followed by photochemical reaction and absorption measurement showed good correlation with the theoretical value. The interference by chloroacetic acid (MCA), dichloroacetic acid (DCA), chloroform (CHCl3), carbon tetrachloride (CCl4), trichloroethylene (TCE), and perchloroethylene (PCE) have also been studied.
  • Naing Kyaw, Masayuki Takahashi, Masahiro Taniguchi, Akihiko Yamagishi
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2424-2429
    Published: 1994
    Released: July 28, 2006
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    The interactions of the enantiomers of [Ru(bpy)2(phi)]Cl2 and [Ru(phen)2(phi)]Cl2 (bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, and phi = 9,10-phenanthrenequinone diimine) with calf thymus DNA were studied by spectroscopic titrations, circular dichroism, and electric linear dichroism methods. These complexes bound to DNA with binding constants greater than 104 M−1. From the CD and LD spectra, the phi ligands of both complexes are concluded to be intercalated between the basepairs of DNA.
  • Koichi Tanaka, Masafumi Ata, Hitoshi Kimura, Hiroshi Imoto
    1994 Volume 67 Issue 9 Pages 2430-2434
    Published: 1994
    Released: July 28, 2006
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    The electronic characteristics of electrochemically doped lithium in non-graphitizable carbon, which was obtained by heat-treating polyfurfuryl alcohol (PFA-C) and was used as the negative electrode of lithium ion rechargeable batteries, were examined with the aid of 7Li solid-state nuclear magnetic resonance (NMR) and electron spin resonance (ESR). In order to clarify how lithium is incorporated in the carbon electrode, discrete variational-Xα (DV-Xα) molecular-orbital calculations were also performed on a model system. These experimental and theoretical results suggest that the lithium doped in the carbon exists in a non-metallic state with low electron density as compared to the ionic crystal, and that the unpaired electrons in the lithium doped carbon are delocalized at the peripheral carbon domains of the system. This was theoretically supported by the fact that the singly occupied molecular orbital (SOMO) of the lithium doped carbon is lower by 5.388 eV than the orbital localized predominantly on lithium 2s, and that the system is stabilized by electron donation from lithium to the carbon.
  • Kazuteru Shinozaki, Youkoh Kaizu
    1994 Volume 67 Issue 9 Pages 2435-2439
    Published: 1994
    Released: July 28, 2006
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    Excited [CuI(dmphen)2]+ (dmphen = 2,9-dimethyl-1,10-phenanthroline) was studied in terms of its molecular structure. The MLCT (metal-to-ligand charge-transfer) transition energy and phosphorescence lifetime of the copper(I) complex in the solid state were reduced with diminishing the dihedral angle between two dmphen ligands. The results of a DV-Xα molecular orbital calculation were in good agreement with the spectroscopic results. In solution, the non-luminous character of [CuI(phen)2]+ (phen = 1,10-phenanthroline), which had no steric-hindered methyl groups retarding the flattening motion, was explained from lowering the lowest excited MLCT state due to a drastic distortion by the photoexcitation.
  • Satoru Onaka, Masa-aki Haga, Shigeru Takagi, Mayumi Otsuka, Katuya Miz ...
    1994 Volume 67 Issue 9 Pages 2440-2446
    Published: 1994
    Released: July 28, 2006
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    Synthesis and X-ray structure analyses were carried out for fac-cis-[MnCl(CO)3dppfe] and fac-cis-[MnH(CO)3dppfe], and a cyclic voltammetric study was made for a series of manganese carbonyl derivatives with 1,1′-bis(diphenylphosphino)ferrocene (dppfe), including these new compounds. Unusually a low oxidation potential for the Mn site is revealed for [Mn(MeCp)(CO)dppfe]. A good correlation between ν(CO) and the oxidation potential for the Mn atom has been clarified.
  • Noriharu Nagao, Masao Mukaida, Eiichi Miki, Kunihiko Mizumachi, Tatuji ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2447-2453
    Published: 1994
    Released: July 28, 2006
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    The emission lifetime (τobs) and quantum yield of photoracemization (φrac) for a series of complexes, [Ru(bpy)n(Hdpa)3−n]2+ (n = 0—3), were studied in aqueous solution at temperatures of between 20 and 60 °C. The values of τobs of [Ru(bpy)2(Hdpa)]2+ were found to vary around 80—200 ns, depending upon temperature, while [Ru(bpy)(Hdpa)2]2+ and [Ru(Hdpa)3]2+ did not emit at the temperature studied. The photoracemization reactions of [Ru(bpy)3]2+, [Ru(bpy)2(Hdpa)]2+, [Ru(bpy)(Hdpa)2]2+, and [Ru(Hdpa)3]2+ were thermally activated with φrac of (0.1—1.6) × 10−3, (0.5—6) × 10−3, (0.04—0.22) × 10−3, and (0.1—0.25) × 10−3, respectively, depending upon the conditions. The photochemical behavior of [Ru(bpy)2(Hdpa)]2+ was explained by a set of excited states, which was assumed to include the 3d–π*bpy, 3d–d*, and 3n–π*bpy states. The reactive state, the 3d–d* state, was thermally yielded from the 3d–π*bpy state. The displacement of a bpy ligand by an Hdpa ligand made the quantum yield of the formation of the 3d–d* state from the 3d–π*bpy state (φd–d) smaller, and the intrinsic quantum yield of photoracemization (φrac(d–d)) larger. The fact that φrac for [Ru(bpy)(Hdpa)2]2+ and [Ru(Hdpa)3]2+ was smaller than that for [Ru(bpy)3]2+ and [Ru(bpy)2(Hdpa)]2+ could be interpreted by assuming that the displacement of the bpy ligand by the Hdpa ligand diminished the quantum yield of the formation of the 3d–d* state from the 3d–π*bpy or 3d–π*Hdpa states considerably, due to the bypath from the 3d–π*bpy or 3d–π*Hdpa states through the 3nHdpa–π*bpy or 3nHdpa–π*Hdpa states to the ground state.
  • Harumitsu Nishikawa, Hideki Monma
    1994 Volume 67 Issue 9 Pages 2454-2456
    Published: 1994
    Released: July 28, 2006
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    Gaseous chlorobenzene was decomposed into CO and CO2 by the oxidative reaction at 400—450 °C over calcium-deficient hydroxyapatite (DAp) prepared by an aqueous precipitation procedure. Phenol and benzene were not detected after the reaction. Most of the Cl in chlorobenzene was captured as Cl- in DAp by the reaction. On the other hand, the DAp prepared by the hydrolysis of α-tricalcium phosphate was inactive for the decomposition of chlorobenzene. The difference in the activity between the two DAp materials was attributed to the difference of their crystallinities.
  • Masakazu Kita, Kazuo Kashiwabara, Junnosuke Fujita, Hitoshi Tanaka, Sh ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2457-2462
    Published: 1994
    Released: July 28, 2006
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    The crystal structures of trans-[CoCl2(dmpe)2]ClO4 (dmpe = 1,2-bis(dimethylphosphino)ethane) (1), trans(Cl,Cl)cis(P,P)-[CoCl2(edmp)2]PF6·0.5CH3OH (edmp = (2-aminoethyl)dimethylphosphine) (2) and trans-[CoCl2(en)2]NO3 (en = 1,2-ethanediamine) (3) were determined by the single-crystal X-ray diffraction method. Crystal data and final R values are: for 1, orthorhombic, Ccca, a = 15.192(3), b = 16.221(4), c = 18.129(3) Å, V = 4468(1) Å3, Dx = 1.58, Dm = 1.60 g cm−3, and Z = 8, and R = 0.041 for 2360 reflections; for 2, orthorhombic, C2221, a = 15.295(4), b = 18.583(5), c = 14.680(4) Å, V = 4172(2) Å3, Dx = 1.59, Dm = 1.63 g cm−3, and Z = 8, and R = 0.099 for 4626 reflections; for 3, monoclinic, P21/n, a = 6.348(1), b = 9.304(1), c = 9.853(1) Å, β = 101.79(1)°, V = 569.6(1) Å3, Dx = 1.82, Dm = 1.85 g cm−3, and Z = 2, and R = 0.043 for 1024 reflections. The Co–P bond distances (av 2.196(3) Å) in 2 is shorter by 0.063 Å than that (av 2.259(1) Å) in 1, while the Co–N bond distance (av 2.039(7) Å) in 2 is longer by 0.079 Å than that (av 1.960(3) Å) in 3, indicating the trans influence of the phosphino group. The metal-ligand bond distances were compared with those of the corresponding trans-dichloro complexes of Fe(II), Fe(III), Cr(III), and Rh(III).
  • Noriyuki Takahashi, Masanori Tanaka, Teiji Satoh, Tadashi Endo
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2463-2467
    Published: 1994
    Released: July 28, 2006
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    “Two dimensional” talc was prepared by the hydrothermal reaction of various silicas with magnesium hydroxide. The precipitated and activated silicas were especially available as starting materials. The powder X-ray diffraction data indicated that the resulting talc consisted of no-stratified and random layered structure. According to the IR spectrum, no solid acidity, i.e. Brønsted and Lewis acid sites were found. The specific surface area was over 500 m2 g−1. A large amount of water was adsorbed and partially combined with the surface of lamellar talc. As a result, the artificial talc would receive applications such as emulsifying agents to the mixture of liquid paraffin and water.
  • Ruo Chun Huang, Hiroaki Okamura, Tetsuo Iwagawa, Munehiro Nakatani
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2468-2472
    Published: 1994
    Released: July 28, 2006
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    Three azedarachins, insect antifeedant limonoids, have been isolated from the root bark of Chinese Melia azedarach Linn (Meliaceae), along with six trichilins. Their structures show a 14,15-epoxide and a 19/29 acyl acetal bridge system, as elucidated by spectroscopic studies. They are antifeedants active against the larvae of Spodoptera exigua Hübner (Boisduval).
  • Akira Tai, Tadashi Kikukawa, Takashi Sugimura, Yoshihisa Inoue, Satosh ...
    1994 Volume 67 Issue 9 Pages 2473-2477
    Published: 1994
    Released: July 28, 2006
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    The ultrasonic irradiation of Raney nickel catalyst in water followed by the removal of the resulting turbid supernatant gave an excellent nickel catalyst (RNi-U) which generated an asymmetrically-modified nickel catalyst. An EPMA (SEM-EDX) study indicated that RNi-U consisted of a fairly pure nickel surface of homogeneous size. Tartaric acid–NaBr-modified RNi-U (TA–NaBr–MRNi-U) showed a high enantio-differentiating ability as well as reactivity in the hydrogenation of prochiral ketones such as 1,3-diones and 3-oxoalkanoic acid esters.
  • Hitoshi Tamiaki, Ayumu Kiyomori, Kazuhiro Maruyama
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2478-2486
    Published: 1994
    Released: July 28, 2006
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    Oligopeptide-linked zinc-porphyrins were prepared (oligopeptide = –Phem–Alan–OMe and porphyrin = 5,15-diaryl-2,3,7,8,12,13,17,18-octaethylporphyrin). 1H NMR, IR, visible, and CD spectra of the synthetic molecule in a chlorinated methane (CDCl3 or CH2Cl2) showed that the carbonyl oxygen of the N-terminal amino acid of the linked peptide should ligate the central zinc metal in the molecule as the axial ligand to form a pentacoordinated zinc-porphyrin. The coordination of the zinc with the peptide framework changed the optical and electrical properties, indicating that such ligation might control the reactivity in biological metallotetrapyrrole–protein systems as well as the coordination to the peptide residue.
  • Noritaka Abe, Akikazu Kakehi
    1994 Volume 67 Issue 9 Pages 2487-2493
    Published: 1994
    Released: July 28, 2006
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    The reaction of ethyl 2-hydrazino-1-azaazulene-3-carboxylate with diphenylcyclopropenone (DPP) gave ethyl (Z)-2-[N′-(3-amino-2,3-diphenylpropenoyl)hydrazino]-1-azaazulene-3-carboxylate, ethyl 8,9-diphenyl-1,2,9b-triazaindeno[1,7,6-bcd]azulene-3-carboxylate, ethyl (E)-3-(1,2-diphenylethyl)-1,2,3a-triazacyclopent[a]azulene-9-carboxylate, and ethyl 2-amino-1-azaazulene-3-carboxylate (8a), together with the products of 8a with DPP. However, the reaction of 2-hydrazino-1-azaazulene with DPP gave 4H-2,3-diphenyl-1,4a-diazabenz[a]azulen-4-one, (Z)-3-[(1-azaazulen-2-yl)amino]-2,3-diphenylpropenamide, 3,4-diphenyl-3,4-dihydro-2H-1,4a-diazabenz[a]azulen-2-one and 2-amino-1-azaazulene. The structures of the obtained products were determined by inspections of their physical and spectral data, as well as single-crystal X-ray structure analyses of some of these compounds. The reaction mechanisms are discussed.
  • Minokazu Takahashi, Yasumasa Sakakibara
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2494-2499
    Published: 1994
    Released: July 28, 2006
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    (1S,6R)-1-Acetoxy-6-(1,3-benzodithiol-2-yloxy)-3,5-cyclovitamin D2 (7) was synthesized from vitamin D2 by five steps. The new compound 7 was ozonized regioselectively and subsequently reduced, leading to (7E)-(1S,3S,5R,6R)-1-acetoxy-6-(1,3-benzodithiol-2-yloxy)-3,5-cyclo-9,10-seco-23,24-dinor-7,10(19)-choladien-22-ol (11). The alcohol 11 obtained as a key intermediate was tosylated, iodinated, and coupled with 2-methyl-4-phenylsulfonyl-2-(tetrahydropyranyloxy)butane to give (1S,6R)-1-hydroxy-6-(1,3-benzodithiol-2-yloxy)-23-phenylsulfonyl-25-tetrahydropyranyloxy-3,5-cyclovitamin D3 (16). By desulfonylation and hydrolysis of the compound 16 1α,25-dihydoxyvitamin D3 was obtained selectively.
  • Hiroshi Imahori, Hiroyuki Higuchi, Yoshihiko Matsuda, Ayano Itagaki, Y ...
    1994 Volume 67 Issue 9 Pages 2500-2506
    Published: 1994
    Released: July 28, 2006
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    A series of (porphyrin)–(C≡C)2–C6H4–R1 (R1 = NO2, H, Me, and OMe) were synthesized by the oxidative coupling of ethynyl porphyrins and phenylacetylenes in the presence of copper(II) acetate in pyridine. Electronic and electrochemical spectra of the compounds with R1 = H, Me, and OMe are quite similar, while pronounced change was observed for the compound with R1 = NO2, especially for the meso-substituted one, indicating that intramolecular charge transfer is responsible for the difference.
  • Toshihide Hatsui, Jin-Jun Wang, Hitoshi Takeshita
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2507-2513
    Published: 1994
    Released: July 28, 2006
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    In the photoaddition reaction of terpinolene with methyl 2,4-dioxopentanoate, the products derived from the tetrasubstituted C=C were four proto-[2+2] photocycloadducts, together with ene reaction products. When these proto-cycloadducts were treated with aqueous sodium carbonate, a facile retro-benzilic acid rearrangement to form substituted cyclopentenone derivatives occurred. The product from the other trisubstituted C=C was an ordinary retro-aldol product of the [2+2] cycloadduct and an ene reaction product. One of the proto-photocycloadducts was transformed into α-chamigren-3-one and further to α-chamigrene.
  • Masahiko Taniguchi, Hideaki Fujii, Koichiro Oshima, Kiitiro Utimoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2514-2521
    Published: 1994
    Released: July 28, 2006
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    Treatment of α-formyl amides with RAlCl2 or PhAlCl2 provided threo-α-alkyl-substituted β-hydroxy amides under high stereocontrol. The method was successfully applied to the selective addition of alkyl group to α-methyl-substituted β-keto amides or esters. Treatment of α-methyl-β-keto amides or α-methyl-β-keto esters with trialkylaluminium or alkylmanganese halide afforded the corresponding erythro (or threo) α-methyl-substituted β-hydroxy amides or α-methyl-substituted β-hydroxy esters with high stereoselectivity.
  • Hideo Togo, Ken Hayashi, Masataka Yokoyama
    1994 Volume 67 Issue 9 Pages 2522-2527
    Published: 1994
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    Alkyl halides were treated with protonated heteroaromatic bases in the presence of 1,1,1,3,3,3-hexamethyl-2,2-bis(trimethylsilyl)trisilane under photochemical conditions to give the corresponding alkylated heteroaromatic bases easily. The alkylation of protonated heteroaromatic bases with 1,1,1,3,3,3-hexamethyl-2-(trimethylsilyl)trisilane proceeded effectively under photochemical conditions or thermal conditions. The present method is the first report on the alkylation of heteroaromatic bases under non-oxidative conditions.
  • Leonard Y. Jayasinghe, Devika Kodituwakku, Andrew J. Smallridge, Mauri ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2528-2531
    Published: 1994
    Released: July 28, 2006
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    The reduction of ethyl acetoacetate to ethyl (S)-3-hydroxybutyrate, mediated by freeze-dried yeast, proceeds in good yield (53—58%) and with high enantioselectivity (>96%ee) in a number of organic solvents; petroleum ether, diethyl ether, toluene, and carbon tetrachloride. A small amount of water (0.8 ml (g-yeast)−1) is required for the reaction to proceed. The water/yeast/substrate ratio and the solvent polarity have been found to significantly influence the reactivity of the system. The enantiomeric excess was determined by gas chromatography employing a chiral column.
  • Naoyuki Shimomura, Teruaki Mukaiyama
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2532-2541
    Published: 1994
    Released: July 28, 2006
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    α-D-Ribofuranosides are stereoselectively synthesized in high yields from 2,3,5-tri-O-benzyl-1-O-iodoacetyl-D-ribofuranose (1) and trimethylsilylated nucleophiles by the use of silver salts in the coexistence of 3 molar amounts of lithium perchlorate, while β-D-ribofuranosides are prepared predominantly in high yields by the reaction of 1 and trimethylsilylated nucleophiles or 2,3,5-tri-O-benzyl-D-ribofuranose and free alcohols by using [diphenyltin sulfide/silver salt] or [Lawesson’s reagent/silver salt] combined catalyst system.
  • Yoichi Kodera,, Shoji Watanabe, Yasushi Imada, Shun-Ichi Murahashi
    1994 Volume 67 Issue 9 Pages 2542-2549
    Published: 1994
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    N,N-Disubstituted and cyclic hydroxylamines can be converted into the corresponding imines efficiently upon treatment with anhydrous titanium trichloride in THF at room temperature. Similar treatment of N-allylhydroxylamines with anhydrous titanium trichloride gives 1-azadienes, which are versatile synthetic intermediates for aza-Diels–Alder reactions. On the other hand, the same hydroxylamines can be converted into the corresponding secondary amines upon treatment with aqueous titanium trichloride in methanol. It is noteworthy that optically active hydroxylamines, which have chirality at the α-position to nitrogen, can be converted into optically active secondary amines without loss of chirality. Dihydro-2(1H)-quinolinones can be prepared upon treatment of 1-hydroxy-3,4-dihydro-2(1H)-quinolinones with aqueous titanium trichloride. The substrates of N,N-disubstituted and cyclic hydroxylamines can be prepared readily upon treatment of nitrones with nucleophiles. Since nitrones can be prepared by metal-catalyzed oxidations of secondary amines with hydrogen peroxide, the present titanium(III)-promoted reaction of hydroxylamines will provide a convenient method for the synthesis of either α-substituted imines or amines from secondary amines.
  • Kazuhiko Tamai, Takashi Kaneko, Makoto Shiomi, Hitoshi Takeda, Mitsuhi ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2550-2553
    Published: 1994
    Released: July 28, 2006
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    Achiral liquid crystal mixtures for the τVmin mode of ferroelectric liquid crystals (FLC) were developed by using laterally fluorinated achiral compounds with an acetylene linkage. The achiral mixtures showed large negative dielectric anisotropy (Δε), low viscosity and an INAC phase sequence. FLC mixtures were prepared by doping chiral compounds into the developed achiral mixtures. The developed FLC mixtures showed low Vmin and fast τmin, giving a low driving voltage and fast line address time.
  • Masato Murakami, Noriaki Manada
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2554-2559
    Published: 1994
    Released: July 28, 2006
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    A novel synthesis of chloroformate was developed by a palladium-catalyzed reaction of Cl2, CO, and alkyl nitrite in the gas phase. When PdCl2/γ-Al2O3 or PdCl2/SiO2 was employed as a catalyst, chloroformate was formed in good yield and with high selectivity. It was confirmed that the reaction did not proceed via phosgene. Cl2 is directly converted to methyl chloroformate. No HCl was formed. The reaction temperature greatly influenced the formation rate of chloroformate, and its selectivity depended on the nitrite/Cl molar ratio very drastically. The dependence of the formation rate on the concentrations of CO and methyl nitrite was also examined.
  • Kazuhiko Matsuzaki, Tadashige Hata, Tatsuo Sone, Junzo Masamoto
    1994 Volume 67 Issue 9 Pages 2560-2566
    Published: 1994
    Released: July 28, 2006
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    A new polyacetal process from formaldehyde polymerization in the presence of a chain-transfer agent was developed. For the acetal homopolymer, highly purified formaldehyde is polymerized in the presence of acetic anhydride. Thus, an end-capped polymer can be obtained during polymerization. This concept gave us a very simple process for manufacturing the acetal homopolymer, compared to the conventional process. If trifunctional or tetrafunctional alcoholic compounds are used as chain-transfer agents, branched poly(oxymethylene) is obtained; the melt viscosity of this branched poly(oxymethylene) shows a higher pressure dependence than the linear poly(oxymethylene). If a functional polymer is used as the chain-transfer agent, which has an active hydrogen, the acetal block copolymer, which shows characteristic properties, can be obtained.
  • Kimio Kunimori, Hisakazu Shindo, Daisuke Nishio, Takeshi Sugiyama, Tos ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2567-2570
    Published: 1994
    Released: July 28, 2006
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    The effect of H2 reduction treatments on H2 chemisorption, ethane hydrogenolysis, and CO hydrogenation over Nb2O5-supported and Nb2O5-modified Ru catalysts has been studied to elucidate the nature of the metal-oxide interaction, and the results are compared with those of a SiO2-supported Ru catalyst. The Ru/Nb2O5 and Nb2O5–Ru/SiO2 catalysts after high-temperature reduction at 500 °C showed a typical SMSI behavior, while a specific Ru–niobia interaction, which resulted in a higher ethane hydrogenolysis activity, was induced even after low-temperature reduction at 200 °C.
  • Yukio Sasaki, Ichiro Komiya, Minoru Handa
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2571-2573
    Published: 1994
    Released: July 28, 2006
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    The physical properties of 3-s-butylsydnone at various temperatures were investigated by dielectric constant, refractive index, density, and viscosity measurements. These physical constants were compared with those of other 3-alkylsydnones. Although the differences in the dielectric constant, refractive index and density between 3-butylsydnone and 3-s-butylsydnone were relatively small, the viscosity of 3-s-butylsydnone became particularly larger than that of 3-butylsydnone at lower temperatures.
  • Ho-Hi Lee, Hitoshi Senda, Kaoru Oyama, Akio Kuwae, Kazuhiko Hanai
    1994 Volume 67 Issue 9 Pages 2574-2576
    Published: 1994
    Released: July 28, 2006
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    Crystals of a polymorph of allocinnamic acid having a melting point of 58 °C are monoclinic, space group P21/c with a = 6.2508(8), b = 15.524(2), c = 8.5067(5) Å, β = 109.295(7)°, and Z = 4. The structure was solved by direct methods and refined to a final R value of 0.042 for 1321 reflections [I > 3σ(I)]. The molecules form centrosymmetric dimers with two O–H···O bonds of carboxylic acid groups [O···O distance, 2.666(1) Å, O···H–O angle, 160.79°]. The plane formed by the olefin group is twisted with respect to the phenyl ring at an angle of 37.8(2)°. The high-resolution solid-state 13C NMR spectra were also measured and may be useful for distinguishing polymorphs of allocinnamic acid.
  • Yoshihisa Fujiwara, Tomohiro Tanaka, Hokuto Ohtani, Yoshifumi Tanimoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2577-2579
    Published: 1994
    Released: July 28, 2006
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    The effect of a magnetic field on optical activity of a product was reinvestigated in photochemical reaction of 4-methyl-2-quinolinecarbonitrile with optically active (S)-(+)-2-phenylpropionic acid. The spectroscopic data show that the product, 4-methyl-2-(1-phenylethyl)quinoline, becomes racemic both in the presence and absence of a magnetic field (45 mT), indicating no induction of the optical activity by the magnetic field.
  • Masaharu Tsuji, Hiroaki Ishimi, Nobuo Kaneko, Yukio Nishimura
    1994 Volume 67 Issue 9 Pages 2580-2582
    Published: 1994
    Released: July 28, 2006
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    There are a number of unclassified XeII lines in the spectral table reported by Striganov and Sventitskii. Among them, electronic transitions of 52 XeII lines can be assigned with reference to the Moore’s atomic energy diagram. The table presented here complements the spectral table of Striganov and Sventitskii.
  • Ikuko Wakeshima, Sazuku Watanabe, Ichiro Kijima
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2583-2585
    Published: 1994
    Released: July 28, 2006
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    The reaction between metallic indium and bis(β-diketonato)copper(II) in non-aqueous solution produced the corresponding indium chelate compounds of the type [In(dik)3], where Hdik denotes CH3COCH2COCH3 (Hacac), CH3COCH2COC6H5 (Hbzac), C6H5COCH2COC6H5(Hdbzm), or (CH3)3CCOCH2COC(CH3)3 (Hdpm). The [In(acac)3] was formed in high yield by the reactions using o-dichlorobenzene, decaline, or DMSO as solvent. The other indium chelate compounds were synthesized by reactions using DMSO as solvent.
  • Yasuo Nakao, Makoto Oonishi, Tomoko Uzu, Hiroko Kashihara, Shinnichiro ...
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2586-2589
    Published: 1994
    Released: July 28, 2006
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    Dinuclear copper(II) complexes, [Cu2(nR)X2] (ClO4)2 (X = N3, NCS, and OAc) have been synthesized and characterized, where nR = N,N,N′,N′-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-1,3-diaminopropane (3Me), N,N,N′,N′-tetrakis[(1-ethyl-2-benzimidazolyl)methyl]-1,3-diaminopropane (3Et), N,N,N′,N′-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-1,4-diaminobutane (4Me), and N,N,N′,N′-tetrakis[(1-ethyl-2-benzimidazolyl)methyl]-1,4-diaminobutane (4Et). Although a weak antiferromagnetic interactions were found for [Cu2(3Me)(NCS)2](ClO4)2·3H2O (coupling constant J = −2.1 cm−1, H = −2JS1·S2) and [Cu2(3Me)(OAc)2](ClO4)2·H2O (J = −2.0 cm−1), no exchange interaction has been observed to 4.2 K for [Cu2(3Me)(N3)2](ClO4)2·H2O. The Electrochemistry of these complexes in N,N-dimethylformamide showed two electron reductions at +210 — −30 mV vs. Ag–AgCl (Cu2+–Cu2+ → Cu+–Cu+).
  • Shuichi Ikenoue, Masahiro Mikuriya, Osamu Miyauchi, Ryoji Nukada, Atsu ...
    1994 Volume 67 Issue 9 Pages 2590-2592
    Published: 1994
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    A series of tungstates soluble in nonaqueous solvents were synthesized and characterized by elemental analyses and IR spectra. The heptameric compound [(t-C4H9)NH3]6[W7O24] was structurally characterized by X-ray diffraction methods.
  • Yasuhiro Tanoue, Kazunori Sakata, Mamoru Hashimoto, Shin-ichi Morishit ...
    1994 Volume 67 Issue 9 Pages 2593-2595
    Published: 1994
    Released: July 28, 2006
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    The oxidative demethylation of polymethoxynaphthalenes such as 1,4-di, 1,4,5-tri, 1,4,5,8-tetra, and 1,2,4,5,8-pentamethoxynaphthalenes with silver-catalyzed ammonium peroxodisulfate gave the corresponding 1,4-naphthoquinones in good yield under mild reaction conditions.
  • Tadashi Hanaya, Yasushi Fujii, Hiroshi Yamamoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2596-2599
    Published: 1994
    Released: July 28, 2006
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    The title sugar analogue (9) was conveniently synthesized from known 3-O-acetyl-5,6-dideoxy-5-dimethoxyphosphinyl-1,2-O-isopropylidene-6-nitro-α-D-glucofuranose in 4 steps via the 6-t-butoxycarbonylamino derivative. The structure of 9 was established by spectroscopy after conversion into the 6-acetamido-1,2,3,4-tetra-O-acetyl-5-methoxyphosphinyl derivatives.
  • Shunsuke Izumi, Hiroyuki Moriyoshi, Toshifumi Hirata
    1994 Volume 67 Issue 9 Pages 2600-2602
    Published: 1994
    Released: July 28, 2006
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    Mosher's method for identification of the absolute configurations of secondary alcohols could be extended to that of tertiary alcohols, such as (1S,2S,5R)- and (1S,2R,5R)-pinan-2-ol, on the basis of its conformational analysis.
  • Takayuki Kawashima, Satoshi Kojima, Naoki Inamoto
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2603-2606
    Published: 1994
    Released: July 28, 2006
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    Sequential treatment of S-methyl (t-butyl)phenyl- or (1-naphthyl)phenylphosphinothioates with lithium dialkylamides at −78 °C and then with alkyl halides at 0 °C—r.t. gave the corresponding (alkylthiomethyl)phosphine oxides, the Wittig rearrangement products, in moderate to good yields along with small amount of their overreacted α-alkylated products. The corresponding alkylphosphine oxide was obtained only in the reaction of naphthyl derivative. Optically active Wittig rearrangement products were given in 82 and 78% optical yields, respectively.
  • Masaya Nakata, Minoru Yasuda, Jin Kawakita
    1994 Volume 67 Issue 9 Pages 2607-2610
    Published: 1994
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    Substitutive cyclization of allylic acetates by an internal secondary hydroxyl group under acidic conditions to yield 2,6-disubstituted tetrahydropyrans has been investigated. The reaction is influenced by the substitution type of the double bond.
  • Kiyotaka Onitsuka, Xin-Qung Tao, Kenkichi Sonogashira
    Type: Accounts
    Subject area: AI
    1994 Volume 67 Issue 9 Pages 2611-2613
    Published: 1994
    Released: July 28, 2006
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    Square planar ferrocenylethynyl transition metal complexes M(C≡CFc)2(PR3)2 (M = Pt, Pd, Ni; Fc = (C5H4)Fe(C5H5)) were prepared by the reaction of MCl2(PR3)2 with ethynylferrocene in the presence of a CuI catalyst in diethylamine, and characterized by spectral analyses. An interaction between transition metals and an iron atom was studied by using electronic spectroscopy.
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