Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 62 , Issue 1
Showing 1-50 articles out of 59 articles from the selected issue
  • Hisashi Uedaira, Mitsuhiko Ikura, Hatsuho Uedaira
    1989 Volume 62 Issue 1 Pages 1-4
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The spin-lattice relaxation times, T1, of H217O have been measured for aqueous solutions of several pentoses, hexoses, di-, and trisaccharides as a function of the concentration at 25 °C. The coordination numbers, nh, and the rotational correlation times, τch, of water molecules around the sugars were estimated and compared with that of pure water, τc°. The value of τch⁄τc°=4.10 for glucose is largest, while that of τch⁄τc°=2.82 for ribose is the smallest, among these sugars. The value of nhch⁄τc°−1) was defined as the dynamic hydration number. The dynamic hydration numbers showed a good correlation with the mean number of the equatorial OH groups and the limiting diffusion coefficients.
  • Tohru Terada, Takashi Nogami, Yasuhiko Shirota
    1989 Volume 62 Issue 1 Pages 5-10
    Published: 1989
    Released: June 27, 2006
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    The phase transitions of a series of title compounds were investigated by means of DSC, IR absorption spectra, and measurements of ionic conductivities. All of the compounds exhibited phase transitions in the range of 77–110 °C. The IR absorption spectra clarified that conformational change in the alkyl chain occurred above the transition temperature. The temperature dependences of the ionic conductivities of BF4 showed conductivity jumps by a factor of 9–120 around the transition temperatures. A comparison of the DSC results and the ionic conductivities of BF4-salts with those of the corresponding Br-salts showed that the former compounds have higher transition temperatures, smaller transition enthalpies (and, accordingly, smaller transition entropies), and smaller values of the conductivity jumps than the latter. These results show that BF4-salts are more rigid than Br-salts in the low temperature phase and that the motion of the alkyl group of the former salts is less vigorous than the latter in the high-temperature phase. By observing the crystal with a polarization microscope under crossed Nicols condition, it was found that optical anisotropy was diminished gradually with the elevation of the temperature and disappeared completely above Tc without changing the crystal shape.
  • Ken-ichi Maruya, Takeshi Fujisawa, Akihiro Takasawa, Kazunari Domen, T ...
    1989 Volume 62 Issue 1 Pages 11-16
    Published: 1989
    Released: June 27, 2006
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    The CO–H2 reaction over ZrO2 was carried out in the presence of various organic additives. The addition of dimethyl ether, methylal, acetaldehyde, and dimethyl acetal showed the marked enhancement effects on the hydrocarbon formation keeping the high selectivity for isobutene. Ethylene was little effective. The addition of acetone, propanal, and propylene resulted in the decrease in the formation of isobutene and the increase in that of n-butenes. The presence of CO and H2 was essential to the selective formation of isobutene. The formation pathways of isobutene and the other hydrocarbons are discussed.
  • Masaaki Baba, Misako Kimura, Toshiyuki Tsuboi, Hajime Kato, Saburo Nag ...
    1989 Volume 62 Issue 1 Pages 17-22
    Published: 1989
    Released: June 27, 2006
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    It is shown that the predissociation of I2 excited to the B3Π0+u state can occur through the coupling with the 24311Πu state by gyroscopic and Zeeman interactions. The interaction matrix elements between the B3Π0+u and 24311Πu states are shown to be nonzero, for the 24311Πu state is mixed significantly with the 24313Π1u state by the spin-orbit interaction. The v, J dependence of the magnetic-quenching ratios of the B3Π0+uX1Σ+g fluorescence intensity has been measured and analyzed. The rate constants of the magnetic predissociation in the B3Π0+u state have also been evaluated. The magnetic-field dependence of the hyperfine structure has been measured by means of the Doppler-free intermodulated fluorescence method.
  • Masakazu Kita, Kazuaki Yamanari, Yoichi Shimura
    1989 Volume 62 Issue 1 Pages 23-32
    Published: 1989
    Released: June 27, 2006
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    Dithiocarbamato complexes, [Co(dtc)3−n(diamine)n]n+ (n=1 and 2 and dtc=dimethyldithiocarbamate) were newly prepared and characterized by means of their absorption, CD, and MCD spectra. (+)500CD-[Co(dtc)(en)2][Sb2(R,R-C4H2O6)2]·5H2O crystallized in the monoclinic space group of P21 with a=14.630(3), b=9.300(1), c=12.023(5) Å, β=110.78(3)°, V=1529.4(8) Å3, and Z=2. The refinement of 3346 reflections (Mo Kα radiation) led to R=0.073. The dtc complex had a Λ configuration. The Co–N bond trans to the dtc sulfur atom was longer by 0.026 A than the cis one. A novel oxidation derivative, [Co{(dimethylamino)thioxomethanesulfinato-O,S}(en)2]2+, was prepared and characterized by means of its XPS spectrum.
  • Hiroshi Sakai, Yutaka Maeda
    1989 Volume 62 Issue 1 Pages 33-38
    Published: 1989
    Released: June 27, 2006
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    125Te and 129I Mössbauer spectra have been measured for the tetragonal (α) and orthorhombic (β) forms of TeO2. The Mössbauer data show that there are no significant differences between the two modifications in either the electronic structure or the chemical bonding of the tellurium atoms; this is consistent with the crystallographic data. From a comparison of the Mössbauer data for 125Te with those for 129I, we have concluded that the 129I daughter nucleus, produced by the nuclear β decay of 129Te, is present in the same lattice environment as the parent 129Te nucleus in TeO2. A Cu125I crystalline compound has been used as the Möossbauer source of 125Te, which emits a single line of resonance γ-ray. The values of the isomer shift and line width for the source are found to be −0.13 mm s−1 relative to the ZnTe standard absorber and 6.53 mm s−1 respectively.
  • Shin-ichi Ishiguro, Honoh Suzuki, Bojana G. Jeliazkova, Hitoshi Ohtaki
    1989 Volume 62 Issue 1 Pages 39-44
    Published: 1989
    Released: June 27, 2006
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    Complexation of copper(II) with chloride ions has been calorimetrically and spectrophotometrically studied in various acetonitrile (AN)–dimethyl sulfoxide (DMSO) mixtures at 25 °C. Complexation of copper(II) ion with DMSO as a ligand in AN has also been investigated calorimetrically. It is indicated that the solvent effect on the thermodynamic parameters of the complexation is dominated by two factors, (1) the preferential solvation of copper(II) ion with DMSO that mainly affects the enthalpies, and (2) the change in solvent–solvent interactions in the bulk that strongly affects the corresponding entropies.
  • Kazuo Miyamura, Keiki Satoh, Yohichi Gohshi
    1989 Volume 62 Issue 1 Pages 45-50
    Published: 1989
    Released: June 27, 2006
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    Nickel(II) complexes coordinated with N,N′-disalicylideneethylenediamine (salen) substituted by a series of n-alkyl side chains have been synthesized. Drastic improvement in the solubility towards chloroform brought about by the increase in alkyl side chain lengths realised an extremely high concentration of 0.5 mol·dm−3. Due to aggregation, their 1H NMR spectra in CDCl3 were strongly dependent on the concentration especially in the high concentration region. The alkyl chain length has very little influence on the dependency, indicating that the aggregation is caused by the complex–complex interaction rather than by the hydrophobic interaction between the alkyl side chains. Assuming a monomer–dimer equilibrium, the aggregation constant is determined from the concentration dependence. Further, the structure of the aggregate is estimated by combining the results of the concentration dependence, and the paramagnetic broadening caused by adding the corresponding copper(II) complex. The paramagnetic broadening investigation also indicated a close contact of copper(II) complex to nickel(II) complex.
  • Yutaka Fukuda, Masako Cho, Kozo Sone
    1989 Volume 62 Issue 1 Pages 51-55
    Published: 1989
    Released: June 27, 2006
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    1,2-Dipiperidinoethane (dipe) forms mixed chelates of the type [Cu(dike)(dipe)]ClO4 with Cu(ClO4)2 and various β-diketonate ions (dike); however, hexafluoroacetylacetonate (hfac) forms [Cu(hfac)2(dipe)] instead. The strong solvatochromism of the former, and the high solubility and volatility of the latter, were compared with those of similar chelates studied so far.
  • Yoichi Abe, Hiroshi Ogino
    1989 Volume 62 Issue 1 Pages 56-60
    Published: 1989
    Released: June 27, 2006
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    The crystal and molecular structures of alkylchromium(III) complexes, trans-[Cr(CH2Cl)(acac)2(H2O)]·EtOH and trans-[Cr(CH2Cl)(acac)2(MeOH)] (acac=2,4-pentanedionate anion, EtOH=ethanol, MeOH=methanol), have been determined by X-ray structure analyses. Both crystals are triclinic and the space group P\bar1; Z=2 with a=9.935(2), b=10.606(2), c=9.399(2) Å, α=90.39(2), β=92.44(2), γ=115.54(1)° for the aqua complex, and Z=4 with a=11.402(6), b=16.780(7), c=8.543(3) Å, α=98.83(3), β=102.00(4), γ=83.03(4)° for the methanol complex. Each complex has trans configuration. The carbon-bonded CH2CI group elongates specifically the Cr–O bond trans to the Cr–C bond in the aqua complex (Cr–O(H2O)=2.134(6) Å) and methanol complex (Cr–O(MeOH)=2.156(6), 2.136(6) Å).
  • Tetsuaki Nishida, Hiroshi Ide, Yonezo Maeda, Hiroyuki Nasu, Toshirou Y ...
    1989 Volume 62 Issue 1 Pages 61-67
    Published: 1989
    Released: June 27, 2006
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    Mössbauer spectra of YBa2(Cu1−xFex)3O7−δ ceramics (x=0.003, 0.008, and 0.017) measured at room temperature show a superposition of three quadrupole doublets. An outermost doublet (δ=0–0.04 mm s−1, Δ=1.94–1.98 mm s−1) is ascribed to high-spin Fe4+ ions present at substitutional sites of Cu2+ ions (Cu(2) site). An intermediate doublet (δ=−0.03–0.02 mm s−1, Δ=1.12–1.17 mm s−1) is ascribed to intermediate-spin Fe3+ ions present at substitutional sites of Cu3+ ions (Cu(1) site). An innermost doublet is ascribed to Fe3+ ions (high spin) with tetrahedral symmetry, present along the b-axis. A decrease in Tc from 72 to 60 K, observed when iron content (x) is increased from 0.008 to 0.017, is explained by a lowered layer structure composed of “dimpled” CuCO4 planes, owing to a displacement of O(4) oxygen atoms sharing CuO5 tetragonal pyramids and CuO4 square planars. One-dimensional chains composed of CuO4 square planars proved to be primarily affected by γ-ray irradiation, whereas no change of Tc was observed. Low-temperature Mössbauer measurements revealed that “partial Debye temperatures” are 330 and 740 K for the chains and layer structure, respectively.
  • Masahiro Minabe, Hidehiro Mochizuki, Masaaki Yoshida, Takashi Toda
    1989 Volume 62 Issue 1 Pages 68-72
    Published: 1989
    Released: June 27, 2006
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    The reaction of 1-bromopyrene with acetic anhydride in the presence of aluminium chloride afforded an ipso-substituted compound, 1-acetylpyrene, in addition to the expected compounds, 6-acetyl- and 8-acetyl-1-bromopyrene. 7-Acetyl-1-bromopyrene was prepared via the acetylation of 2-acetylamino-1-bromo-4,5,9,10-tetrahydropyrene. The structures of the acetylbromopyrenes were assigned according to the two-dimensional NMR spectra.
  • Kohichi Yamashita, Shûta Kajiwara, Katsutoshi Ohkubo
    1989 Volume 62 Issue 1 Pages 73-78
    Published: 1989
    Released: June 27, 2006
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    The photoreduction of tris(acetylacetonato)cobalt(III) (Co(acac)3) by 1-benzyl-1,4-dihydronicotinamide (BNAH) was examined with or without methylviologen in the wavelength range of 340–410 nm. The reaction rate of electron transfer from BNAH to Co(acac)3 was considerably enhanced by methylviologen, especially, in lower polar environments; The weaker the hydrophobic interaction between BNAH and the substrate become, the more effectively methylviologen acts as an electron mediator for the above photoreaction. The reaction mechanism is also discussed with particular reference to the participation of the electron mediator in the elementary steps of the present photoinduced reaction.
  • Satoshi Inagaki, Takeo Imai, Yoshio Mori
    1989 Volume 62 Issue 1 Pages 79-82
    Published: 1989
    Released: June 27, 2006
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    The site selectivities of the metalation reactions of dimethylnaphthalenes and dimethylanthracenes followed by MeOD quenching were investigated experimentally and theoretically. The 2(3)-methyl groups were found to be more effectively metalated than expected from the LUMO amplitudes of the aromatic rings. The MNDO calculations suggested that the naphthylmethyl and anthrylmethyl anions are not the aromatic rings perturbed by the carbanions, but the significantly different conjugated rings doubly bonded to the exocyclic carbon atoms. The unexpectedly strong interactions of the carbanion centers with the aromatic rings can account for the discrepancies between the selectivities and the LUMO amplitudes.
  • Koichiro Naemura, Rink\={o} Fukunaga, Masanori Komatsu, Masatoshi Yama ...
    1989 Volume 62 Issue 1 Pages 83-88
    Published: 1989
    Released: June 27, 2006
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    Five new optically active crown ethers and six optically active dipodands are reported. The crown ethers were synthesized by using (+)-(1S,4R,5S,8R)-2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene-4,8-diol and (+)-(1S,4R,5S,8R)-4,8-bis(hydroxymethyl)-2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene as a chiral subunit and the dipodands contained the 2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene residue as a chiral anchor group. The enantiomer recognition behaviour of these compounds was evaluated by the enantiomer differential transport of methyl (±)-phenylglycinate and (±)-1,2-diphenylethylamine hydrochloride through bulk liquid membrane.
  • Takashi Keumi, Toshiaki Umeda, Yoshinori Inoue, Hidehiko Kitajima
    1989 Volume 62 Issue 1 Pages 89-95
    Published: 1989
    Released: June 27, 2006
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    The reaction of arenediazonium tetrafluoroborates with chlorotrimethylsilane in a tetrahydrofuran/N,N-dimethylformamide (DMF) (5v/3v) solution afforded the protodediazotization products in high yields. The reactions of the diazonium salts with halotrimethylsilanes in DMF were found to give the corresponding haloarenes. Among the halodediazotization reactions, the iododediazotization with iodotrimethylsilane proceeded smoothly at room temperature to give the iodoarenes in excellent yields. In a similar manner, a variety of azidoarenes were obtained in consistently high yields by the treatment of arenediazonium tetrafluoroborates with azidotrimethylsilane in a DMF solution.
  • Kenichi Nakabayashi, Jun-ichi Kojima, Kimiko Tanabe, Masahide Yasuda, ...
    1989 Volume 62 Issue 1 Pages 96-101
    Published: 1989
    Released: June 27, 2006
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    Photosensitized reactions of 2,2-diaryloxetanes by 1,4-dicyanonaphthalene, 1-cyanonaphthalene, and 9,10-dicyanoanthracene, which give such ring-cleavage products as substituted benzophenones and alkenes, have been investigated. Quantum yields for the ring cleavage vary with the substituents on both the aryl group and oxetane ring. The quantum yield increases with increase in electron-donating ability of the oxetane. The limiting quantum yields in the case of 1,4-dicyanonaphthalene-photosensitized reaction of 2,2-di-p-tolyl- or 2,2-bis(p-mechoxyphenyl)-3,3,4-uimethyloxetane exceed unity. The mechanism is discussed in terms of electron transfer from oxetanes to the excited singlet state of the sensitizer as well as the regeneration process of the oxetane cation radical involving the hole transfer from substituted benzophenone cation radicals to oxetanes in the chain process.
  • Shinji Takeoka, Hidetaka Iwai, Hiroyuki Ohno, Eishun Tsuchida
    1989 Volume 62 Issue 1 Pages 102-108
    Published: 1989
    Released: June 27, 2006
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    The absorption maximum (λmax) of 1,2-bis(2,4-octadecadienoyl)-sn-glycero-3-phosphorylcholine (DODPC), dispersed in an aqueous medium as liposomes, showed blue shift from 256.8 nm to 241.8 nm when these liposomes were cooled down from liquid crystalline state to gel state. The blue shift is explained to be due to stronger interaction between diene groups at gel state. This diene-containing lipid is examined to be an excellent membrane probe because it is typical phospholipid and miscible with several lipids. Furthermore, the dienoyl groups are known to be settled in the definite positions in bilayer membrane by suitable chemical modification. Phase transition behaviors of various 2,4-octadecadienoyl-containing phosphorylcholines as analogs for DODPC have also been investigated. Although they had similar spectral shifts at gel-to-liquid crystalline phase-transition temperature, their phase-transition temperatures and magnitude of λmax shifts were revealed to be related directly and therefore be governed by the different packing of the diene groups in bilayer membrane. DODPC was mixed with 1,2-dipalmitoyl-sn-glycero-3-phosphorylcholine, or cholesterol, and phase behaviors of these mixed liposomes were also examined. Phase-transition of the mixed liposomes was detected easily by the shift of its λmax with high sensitivity. Results were quite comparable to those obtained from other measurements, such as DSC, NMR, and so on.
  • Tadashi Shiraiwa, Kazuo Kataoka, Shinji Sakata, Hidemoto Kurokawa
    1989 Volume 62 Issue 1 Pages 109-113
    Published: 1989
    Released: June 27, 2006
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    Either (R)- or (S)-cysteine ((R)- or (S)-Cys) was efficiently obtained from (RS)-Cys by the asymmetric transformation via formation of (RS)-4-thiazolidinecarboxylic acid ((RS)-THC) or (RS)-2,2-dimethyl-4-thiazolidinecarboxylic acid ((RS)-DMT) and by using (2R,3R)- or (2S,3S)-tartaric acid ((R)- or (S)-TA), as a resolving agent, in acetic acid. The asymmetric transformation was carried out by combination of crystallization of less soluble salt of (S)-THC or -DMT with (R)-TA (or salt of (R)-THC or -DMT with (S)-TA) and epimerization of soluble diastereomeric salt. The (R)- and (S)-THCs from the less soluble salts gave approximately optically pure (R)- and (S)-Cys’s, respectively, in 64% yield. The asymmetric transformation via formation of (RS)-DMT was more successfully achieved by adding 0.1 molar equivalent of salicylaldehyde; that is, hydrolysis of the obtained less soluble salt gave optically pure (R)- and (S)-Cys’s, respectively, in 80% yield based on the (RS)-Cys used as the starting material.
  • Yutaka Okada, Noriyuki Yamamoto, Takatoshi Hayashi
    1989 Volume 62 Issue 1 Pages 114-118
    Published: 1989
    Released: June 27, 2006
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    The oxidation reactivity of (o-substituted phenyl)ferrocenes with air was measured in acidic solution. The reactivity of o-acetyl, o-methoxycarbonyl, and o-methoxy derivatives was higher than that of the corresponding p-isomers. On the other hand, for o-hydroxy and omethyl derivatives, the reactivity was lower than that of p-isomers. It was considered that the reactivity of o-isomers is influenced by the coordination ability of proton to iron atom. The coordination ability is governed by both the I-effect and steric effect of substituent.
  • Akikazu Kakehi, Suketaka Ito, Tuneo Fujii, Yuichiro Morimoto, Shin-ich ...
    1989 Volume 62 Issue 1 Pages 119-127
    Published: 1989
    Released: June 27, 2006
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    The reactions of 2-(ethoxycarbonylmethylthio)indolizines having an acyl and/or a cyano group at the 1- and 3-positions under several alkaline conditions were examined, and title compounds, thieno[3,2-a]- and thieno[2,3-b]indolizine derivatives were obtained in fairly good yields. The cyclization modes observed in these transformation reactions were in accord with those expected by the molecular orbital calculations using some model compounds and by the stereochemical consideration of starting indolizines. The alkylations of 3-hydroxythieno[3,2-a]- and 3-hydroxythieno[2,3-b]indolizines were also investigated and the corresponding O- and C-alkylated heterocycles were formed in good yields.
  • Tetsuo Nozoe, Kahei Takase, Masafumi Yasunami, Masayoshi Ando, Hiroaki ...
    1989 Volume 62 Issue 1 Pages 128-142
    Published: 1989
    Released: June 27, 2006
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    Treatment of a wide variety of 2-(2-arylhydrazino)tropones with ethanolic acid at 50–80°C readily gave the benzidine type rearrangement products, 2-amino-5-(4-aminoaryl)tropones, besides minor amounts of byproducts of various type. The main products were conveniently led to the corresponding 5-aryltropolones. Similarly, 2-(2-arylhydrazino)tropones bearing an isopropyl and isopropenyl group at the 4-position afforded 4-substituted 2-amino-5-(4-aminoaryl)tropones as the main products, which were also led to 4-substituted 5-(4-acetamidoaryl)- and 5-(4-methoxyaryl)tropolones. Structural assignments of these products were made on the basis of 1H NMR and other spectral data as well as of chemical transformations to known 5-phenyltropolone and also to 2-acetamido-8-hydroxy-10,10-dimethylcyclohept[a]inden-7(10H)-one. This synthetic scheme may possibly be utilized for a convenient synthesis of B-ring-open analogues of colchicine.
  • Katsukiyo Miura, Yoshifumi Ichinose, Kyoko Nozaki, Keigo Fugami, Koich ...
    1989 Volume 62 Issue 1 Pages 143-147
    Published: 1989
    Released: June 27, 2006
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    The reduction of organic halides with tributyltin hydride in the presence of a catalytic amount of triethylborane has been studied. (1) Alkyl iodides and alkyl bromides reacted easily with tin hydride at −78°C to give the corresponding hydrocarbons, while alkyl chlorides were sluggish to react and recovered unchanged. (2) The reduction of alkenyl halides such as 1-deuterio-1-iodo-1-dodecene and 1-iodo-1-triethylsilyl-1-dodecene proceeded nonstereospecifically. (3) The reduction of aryl halides with n-Bu3SnH–Et3B system was not so effective as the reduction of alkyl halides and alkenyl halides. Whereas aryl iodides were reduced at room temperature with n-Bu3SnH, aryl bromides hardly reacted with n-Bu3SnH even at 80 °C.
  • Seizo Tamagaki, Kenji Suzuki, Waichiro Tagaki
    1989 Volume 62 Issue 1 Pages 148-152
    Published: 1989
    Released: June 27, 2006
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    The role of catechol in benzene hydroxylation with Fe3+/catechol/H2O2 system, the so-called Hamilton system, has been mechanistically investigated by using tiron as a substitute for pyrocatechol. The yield of phenol progresses linearly with reaction time. The phenol yield is dependent on the mole ratio of Fe3+ relative to tiron, and the ratio of more than unity is particularly important for the effective functioning of the catalyst system. The o-, m-, and p-product isomer distributions for a few aromatic hydrocarbons are nearly identical with those of the Fenton reaction. These and the separate experimental results are consistent with the mechanism involving the rate-limiting redox reaction between tiron and Fe3+ and then the follow-up radical chain sequence as in the Fenton reaction.
  • Seizo Tamagaki, Masaaki Sasaki, Waichiro Tagaki
    1989 Volume 62 Issue 1 Pages 153-158
    Published: 1989
    Released: June 27, 2006
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    Electron-transfer agents such as N,N,N′,N′-tetramethylphenylenediamine (TMPD), ferrocenes, and phenothiazines have been found to mediate the hydroxylation of benzene with H2O2 in the presence of Fe3+. Of these, TMPD catalyst is the most effective to provide phenol in 80% or better yield based on added H2O2 under the optimized conditions. A general mechanism, involving the rate-determining reduction of Fe3+ to Fe2+ with such mediators, is suggested.
  • Seizo Tamagaki, Masaaki Sasaki, Waichiro Tagaki
    1989 Volume 62 Issue 1 Pages 159-163
    Published: 1989
    Released: June 27, 2006
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    A new combination of the Udenfriend reagent and a flavin analogue was found to hydroxylate benzene to phenol. Effects of temperature and concentrations of reaction components, i.e., iron(II), flavin, and ascorbate, on the phenol yield were examined. In particular, decreasing ascorbate concentration increased the yield of phenol. Thus, 68% of the yield was obtained under better conditions. The mechanism of action of ascorbic acid and the flavin was discussed.
  • Tetsuo Otsubo, Yoshio Aso, Fumio Ogura, Soichi Misumi, Atsushi Kawamot ...
    1989 Volume 62 Issue 1 Pages 164-170
    Published: 1989
    Released: June 27, 2006
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    The title compound was synthesized in a similar manner to a simple access to triple-layered [2.2][2.2]paracyclophane. Its structure was elucidated by X-ray crystallographic analysis. The outer naphthalene rings are bent into a boat form and the inner naphthalene ring is bent into a twist form. These naphthalenes are stacked in layers within van der Waals contact. Therefore, there is a strong transannular π-electronic interaction between them, which brings about characteristic bathochromism, hyperchromism, and broadening in the electronic spectrum. These effects are more prominent than those of the double-layered homologue.
  • Shuji Kanemasa, Norihiko Nakagawa, Hiroyuki Suga, Otohiko Tsuge
    1989 Volume 62 Issue 1 Pages 171-179
    Published: 1989
    Released: June 27, 2006
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    A sequence of cycloadditions of (diethoxyphosphinyl)acetonitrile oxide with α,β-unsaturated esters, the Raney Ni reduction of the resulting cycloadducts, the Horner–Emmons olefination, and the carbonyl reduction with sodium borohydride leads to 5-[(E)-1-alkenyl]-3-hydroxy-4,5-dihydro-2(3H)-furanones which can be converted into (Z)-5-alkylidene-2(5H)-furanones in two steps.
  • Shuji Kanemasa, Norihiko Nakagawa, Hiroyuki Suga, Otohiko Tsuge
    1989 Volume 62 Issue 1 Pages 180-184
    Published: 1989
    Released: June 27, 2006
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    Under acid catalysis, α-hydroxy-γ-oxo acetals which are readily available from the nitrile oxide cycloaddition route are smoothly converted into γ-oxo esters. This unusual and high-yield transformation involves rare acid-catalyzed deconjugation of the intermediary 4-oxo-2-alkenal acetals and is influenced by a substituent at the 5-position.
  • Hiroyuki Takahashi, Takao Hiraide, Yohji Hashida, Shizen Sekiguchi
    1989 Volume 62 Issue 1 Pages 185-188
    Published: 1989
    Released: June 27, 2006
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    The formation of 2,4-disubstituted anionic σ complex, followed by the formation of 4,4-disubstituted one was confirmed by means of absorption and NMR spectra in the reaction of 4-piperidino-1,3-dinitrophenanthrene with potassium methoxide in DMSO–CH3OH. The rates and activation parameters were determined by kinetic studies using stopped-flow and conventional spectrophotometers. It was found, compared with the previous results on the naphthalene system that the presence of H5 of the title compound affects the rates differently.
  • Hiroyoshi Kamogawa, Tomoo Kitamura
    1989 Volume 62 Issue 1 Pages 189-192
    Published: 1989
    Released: June 27, 2006
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    N-Methyl-N-nitroso-p-styrenesulfonamide (1) was synthesized starting with sodium p-styrenesulfonate (3). Monomer 1 and sodium p-styrenesulfinate (2), also synthesized starting with 3, were polymerized and polymer of 2 was converted to corresponding free acid (9). The function of polymer of 1 as the reagent attaching the CH2 group to the carbonyl carbon by insertion and that of polymer 9 as the catalyst for cis→trans isomerization were investigated for various compounds, including cyclohexanone and benzaldehyde and ethyl oleate. The effects of these polymer reagents as compared with those of the corresponding model compounds were discussed.
  • Hiroshi Suginome, J. B. Wang
    1989 Volume 62 Issue 1 Pages 193-197
    Published: 1989
    Released: June 27, 2006
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    We describe the transformation of commercially available 3α-hydroxy-5β-pregnane-11,20-dione acetate (1) into 11-oxaprogesterone (15) in 11 steps including the regioselective β-scission of an alkoxyl radical as a key step.
  • Masaaki Iwata, Hiroyoshi Kuzuhara
    1989 Volume 62 Issue 1 Pages 198-210
    Published: 1989
    Released: June 27, 2006
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    A general synthetic method applicable to acyclic and cyclic polyamines was developed. The methodology was exemplified by systematical synthesis of twelve macromonocyclic polyamines, 1 ([17]N4) through 12 ([35]N8), composed of the combination of four natural polyamine segments, spermidine, spermine, thermine, and thermospermine. These twelve designed macrocycles are exhausted numbers of possible structures defined by three arbitrarily chosen criteria concerning with methylene chain arrays and nitrogen content (four to eight). The common elements of the structural characteristics were analyzed and were found to be reduced to readily available three classes of simple N,N′-ditosylalkanediamines derived from diamines and triamine. Nitrogen content was increased systematically through the reaction of N,N′-ditosylalkanediamine with one of three ω-phthalimidated electrophiles followed by regeneration of the same functionality at symmetrical both terminals as the starting materials via a series of transformation reaction, in excellent yields. Tractable formamide intermediate profits the facile synthesis of acyclic polyamines with long chains. Cyclization was achieved, under high dilution conditions, through the reaction of α,ω-bis(tosylamide) with α,ω-ditosylates in DMF in the presence of cesium carbonate. The cyclization occurred in practical synthetic yields even in the formation of multi-membered ring when the shorter electrophile and the longest α,ω-bis(tosylamide) reacted.
  • Yohsuke Yamamoto, Tohru Tsuchiya, Masahide Ochiumi, Shin-ichi Arai, Na ...
    1989 Volume 62 Issue 1 Pages 211-218
    Published: 1989
    Released: June 27, 2006
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    The reaction of 3-aryl-5-benzoyl-2-imino-2,3-dihydro-1,3,4-thiadiazoles (6) with dimethyl acetylenedicarboxylate (4b) gave the corresponding thiazole (8) and benzoyl cyanide through sulfurane (B) by 1,3-dipolar cycloaddition and cis- (9) and trans-vinyl (10) compounds through zwitterion (C) by simple addition. Two types of addition reactions competed each other and the ratio of the two [R=B/C] depended solely on the solvent polarity (ET). Dibenzoylacetylene behaved similarly. Several iminothiazolines and iminothiadiazolines reacted with activated acetylenes and the selectivity for the two types of addition reactions for each system was shown to be affected by quite subtle balance of electron-withdrawing ability of each heterocycle.
  • Toshio Koizumi, Toshio Fuchigami, Tsutomu Nonaka
    1989 Volume 62 Issue 1 Pages 219-225
    Published: 1989
    Released: June 27, 2006
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    It was found that oxidation potentials of methanes with π-electron substituents were decreased by introduction of a trimethylsilyl group. The anodic oxidation of benzyl-, allyl-, aryl(or alkyl)thiomethyl-, and aryloxymethyl-substituted trimethylsilanes smoothly proceeded in the presence of nucleophiles, e.g. alcohols and carboxylic acids, to eliminate the trimethylsilyl groups giving the corresponding alkoxylated and carboxylated products in moderate or high yields without full optimization of electrolytic conditions, while aminomethylsilanes did not undergo such a kind of anodic oxidation.
  • Jun Niwa
    1989 Volume 62 Issue 1 Pages 226-233
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Substituent effects have been modeled using both substituted hydrogens and substituted benzenes perturbed with point charges in order to separate the inductive (field) effect from the mesomeric effect with the use of ab initio techniques. Several pure dipole ‘substituents’ have been introduced to derive the scale of inductive effects common to both aliphatic and aromatic systems. In the above systems the interaction energies have been estimated by dividing into electrostatic interaction and polarization. Calculations with the use of 4-31G basis set show satisfactory correlations with the experimentally determined substituent constants. The propriety of the present approach has also been examined for the gas-phase acidities of phenols.
  • Akira Ohtani, Takeo Shimidzu
    1989 Volume 62 Issue 1 Pages 234-238
    Published: 1989
    Released: June 27, 2006
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    Polypyrroles were prepared by the chemical polymerization of pyrrole using various combinations of Fe3+ oxidants and electrolytes. The morphology and yield of the resulting polymers were affected by the property of the electrolyte anion in the oxidative solution. The size of the particles of the resulting polymers was decreased by using a high-molecular-weight polymer anion as the electrolyte anion. Both the polymer anion and Cl were incorporated as a dopant into the polypyrrole matrix during the chemical polymerization of pyrrole, using an aqueous solution containing both FeCl3 and the polymer anion. On the contrary, the polymer anion was effectively incorporated as a dopant into the polypyrrole matrix during the chemical polymerization of pyrrole, using an aqueous solution containing both Fe(OH)3 and the polymer acid. A novel type of chemical preparation of the polypyrrole-polymer anion composite using the Fe(OH)3 oxidant and the polymer acid was developed.
  • Osamu Suzuki, Seiichi Inoue, Kikumasa Sato
    1989 Volume 62 Issue 1 Pages 239-243
    Published: 1989
    Released: June 27, 2006
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    In the presence of a catalytic amount of Pd(0), active methylene compounds were allylated by allyl imidates under neutral conditions. In allylation with 3,3-disubstituted allyl imidates, e.g., geranyl and neryl imidate the effect of solvent and ligand to the E/Z ratio are investigated. The reaction in dimethyl sulfoxide by addition of diphosphine, e.g., 1,2-bis(diphenylphosphino)ethane, or large excess of triphenylphosphine as additive ligand gave best results. In these conditions, various active methylene compounds were allylated stereoselectively, especially complete retention of starting olefin geometry was achieved with neryl imidate.
  • Makoto Ando, Hiroyoshi Kuzuhara
    1989 Volume 62 Issue 1 Pages 244-250
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A pyridoxamine analogue-like chiral pyridinophane with two sulfonyl groups in the bridging chain, (S)-15-aminomethyl-14-hydroxy-2,8-dithia[9](2,5)pyridinophane S,S,S′,S′-tetraoxide ((S)-7), was prepared by oxidation of the sulfide precursor, (S)-2. The amino group was successfully transferred from (S)-7 to several 2-oxo carboxylic acids in methanol at room temperature in the presence of one-half equimolecular zinc(II) ion, giving (R)-amino acids in excess. The reaction rates of this nonenzymatic transamination using chiral (S)-7 were much smaller than those of the corresponding reaction using chiral (S)-2. The enantiomeric excess of the amino acids obtained through the reactions of (S)-7 was compared with those of (S)-2, showing that (S)-7 was more efficient than (S)-2 for the preparation of (R)-alanine, but was less than that of (S)-2 for the preparations of (R)-valine, (R)-leucine, and (R)-phenylalanine. These results aroused some doubt about the previous explanation of the stereochemical features of such nonenzymatic transamination reactions.
  • Kiwamu Yamaoka, Yasumori Hino
    1989 Volume 62 Issue 1 Pages 251-256
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The pulsed electric birefringence at 633 nm and dichroism at 462 nm of the title cationic compound (DAES) were measured at 20 °C over a wide electric field strength range (0.1–24 kV cm−1) in the presence of poly(p-styrenesulfonate) (NaPSS) and poly(L-α-glutamate) (PGA) in aqueous solutions at various mixing ratios (P/D) of the polymer to the ligand. The steady-state electric birefringence δ of NaPSS–DAES complexes was positive, while that of NaPSS was negative. The optical anisotropy factor of bound DAES was responsible for the sign reversal. The reduced electric dichroism of NaPSS–DAES at a P/D of 1.9 was +0.38 at infinitely high fields. A value of ±50° was found for the average angle between the orientation axis of the complex and the direction of the optical transition moment at 462 nm of bound DEAS chromophores. No appreciable permanent dipole moment was present in any of the NaPSS–DAES systems. The field orientation was due mostly to counterion-induced moments. The rotational relaxation time was determined from the decay signals. For PAG–DAES and PGA at pH 6.4 and 4.1, the sign of δ was always positive, the magnitude differing from each other by only 10–20%.
  • Akira Shibata, Sinsuke Yamashita, Satoru Ueno, Takuya Yamashita
    1989 Volume 62 Issue 1 Pages 257-261
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Incorporation of polypeptides with hydrophobic side groups into lipid bilayers was achieved by the polymerization of N-carboxy anhydrides of γ-dodecyl L-glutamate and of γ-benzyl D-glutamate in DMPC liposomal membrane under reduced pressure and normal pressure. The effects of polypeptide conformations on the barrier properties of liposomal membrane incorporating polypeptide were examined. There was little difference in the trapping volume when liposomes prepared under reduced pressure and normal pressure were compared. The incorporation of polypeptides into the membrane bilayer had a tendency to decrease the volume trapping efficiencies. It was found that in the membrane-free aqueous phase, polymerization of N-carboxy amino acid anhydrides promoted formation of β-structure and in the membrane bilayer formation of α-helix structure was enhanced. The content of α-helical polypeptide was maximum for liposomes prepared under reduced pressure. The activation energies for water permeation across the liposomal membrane were lowered by the incorporation of polypeptdes into the membrane bilayer. The incorporation of α-helical polypeptide was more ceffective than that of β-structured one for the lowering of activation energies. The permeability barrier properties of liposomal membrane were larger for liposome incorporating poly(γ-dodecyl L-glutamate) (PDOLG) than for liposome incorporating poly(γ-benzyl D-glutamate)(PBDG). This seems to be due to a difference in miscibilities with lipid in the membrane bilayer.
  • Yasushi Inoue, Hiromichi Yamazaki, Mitsuji Ikeda
    1989 Volume 62 Issue 1 Pages 262-266
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The effect of a heat treatment was studied on the sodium isotopic exchange rate between the hydrous niobium(V) oxide in the Na+ form and aqueous solutions. The rate was controlled by the particle diffusion of sodium ions and increased with the heat-treatment temperature. The increase in the rate for the exchanger heat-treated at 200 °C was due to a decrease in the effective particle radius brought about by cracks which developed in the particles. A further increase in the rate at temperatures higher than 200 °C could be explained in terms of an increase in the Na+-diffusion coefficient, which was produced by an increase in the pore size responsinble for the movement of sodium ions.
  • Shoji Sato, Takao Takayanagi, Makoto Watanabe
    1989 Volume 62 Issue 1 Pages 267-274
    Published: 1989
    Released: June 27, 2006
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    Magnesium bis(phosphorodiamidate) hexahydrate and calcium bis(phosphorodiamidate) dihydrate were made by adding an aqueous solution of magnesium chloride or calcium chloride to a sodium phosphorodiamidate solution. These phosphorodiamidates reacted with the water of crystallization and/or adsorbed water to produce phosphoramidate and orthophosphate. They also reacted with HCl gas, acetic acid, and oxalic acid to make polyphosphates and phosphates with amino and/or imino groups. Several typical reactions are as follows:
    (Remark: Graphics omitted.)
    where M and HA stand for alkaline earth metal and acid respectively.
  • Shin-ichi Hirano, Pan-chae Kim
    1989 Volume 62 Issue 1 Pages 275-278
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Synthesis and crystal growth of GaPO4 have been carried out in order to elucidate the properties of gallium orthophosphate. Single crystals were hydrothermally grown in the low temperature range from 150 to 180 °C. Solubility of GaPO4 was measured under hydrothermal conditions, and the temperature coefficient of solubility was found to be negative in H3PO4 solution. Single crystals have morphologies bounded by the major rhombohedral (10\bar1 1) faces under lower temperature and pressure conditions. Polymorphs of GaPO4 exist corresponding to low quartz type, low and high cristobalite types.
  • Walid Ahmad Badawi
    1989 Volume 62 Issue 1 Pages 279-284
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Calorimetric studies on the behavior of the enthalpy of formation at 573 K in the system tin–antimony have been carried out at the compositions 44, 50, 57 at-% Sb using a presently constructed calorimeter. The enthalpy of mixing at 943 K has been determined in the whole range of composition. The relation of the behavior of mixing to that of formation is found as predicted earlier. The enthalpy of formation displays a pronounced temperature dependence above 623 K. The thermodynamic properties of the alloy SnSb at the three compositions exclude a transformation from β to β′ phase around 600 K. Also estimated entropy terms indicate the absence of such a transformation. Earlier reported additional β phase in the system Sn–Sb seemed therefore not to be present.
  • Walid Ahmad Badawi
    1989 Volume 62 Issue 1 Pages 285-289
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The paper presents results of calorimetric studies on the enthalpies of mixing and formation in the system lead–indium. The enthalpy of formation is negative and becomes more negative at higher composition. The partial enthalpy of formation of lead is negative but increases at higher composition. The partial enthalpy of formation of indium is also negative and decreases with increasing the composition. The enthalpy of formation displays a considerable temperature dependence which seems to be smaller than that observed for the enthalpy of formation in other systems.
  • Biswajit Choudhury, T. K. Chandrashekar
    1989 Volume 62 Issue 1 Pages 290-294
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The interaction of metallo derivatives of tetraphenylchlorin (TPC) and octaethylporphyrin (OEP) with 2,4,7-trinitrofluorenone (TNF) is described in terms of 1 : 1 molecular complexes. The binding constants vary as CuOEP>ZnOEP>CuTPC>ZnTPC and this variation is accounted in terms of the structure of the macrocycle and the substituents presen on it. ESR studies of the complexes reveal that the π-complexation results in changes in the electronic structure of the central metal ion. The magnitude of different proton shifts of the acceptor in 1H NMR spectra of the complexes are used to arrive at the possible solution structure of the complexes.
  • Meenakshi Maruthamuthu, E. Subramanian
    1989 Volume 62 Issue 1 Pages 295-303
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The binding of Evans Blue (EB) to poly(N-vinyl-2-pyrrolidone) (PVP) was studied at two pH’s 7.2 and 11.2 spectrophotometrically by absorbance change method. At pH 7.2, the absorption spectrum of EB changed unusually on adding PVP and this indicated the formation of two types of spectroscopically distinguishable PVP–EB complexes. At very low [PVP], a weak complex was formed which got converted into a strong complex at high [PVP]. Positive cooperativity was found to be operative in this conversion and in the strong complex at higher [PVP]. Scatchard, Hill, and Schwarz methods were employed to analyze this cooperativity and to determine the binding parameters. The analysis revealed: (i) the binding constants for the weak and strong complexes were of the order of 104 and 105 dm3 mol−1 respectively; (ii) positive cooperativity at higher [PVP] was due to the interaction of neighboring binding sites on different polymer chains. At pH 11.2, only one type of complex was formed with higher affinity. But the binding behavior remained the same as at pH 7.2.
  • Walid Ahmad Badawi, Ahmed M. Oun
    1989 Volume 62 Issue 1 Pages 304-308
    Published: 1989
    Released: June 27, 2006
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    The enthalpy of dissolution in the system Ag–In has been measured at 1100 K in the whole range of composition. The behavior of the enthalpy of dissolution points out the existence of the compound Ag3In in the liquid state. The enthalpy of formation in the range of the γ phase has also been determined at 623 and 773 K. The enthalpy of formation is negative. The partial molar enthalpy of formation of silver is negative but increase with the increase of the composition, and that of indium is negative and decreases with increasing composition. The enthalpy of formation depends insignificantly on the temperature. A pronounced temperature dependence of the enthalpy of formation seemed not to be a general property of all metallic alloys as reported earlier.
  • Nurul Islam, S. B. A. Zaidi, Aijaz Ahmad Ansari
    1989 Volume 62 Issue 1 Pages 309-316
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The molar conductivities of Et4NBr, n-Pr4NBr, n-Bu4NBr, and n-Bu4NBPh4 have been measured in N,N-dimethylformamide–methyl ethyl ketone (DMF–MEK) mixtures (34.5≥D≥20.10) over the maximum concentration range (2×D3×10−7 mol dm−3) along with the densities and viscosities of the solvent mixtures at 25 °C. The conductance data have been analyzed by using the Fuoss-1978 (F78) conductance equation and the results compared with those obtained from the Justice (J) and the Fuoss-Onsager-Skinner (FOS) equations. The molar conductivities at infinite dilution (Λ0), the thermodynamic association constant (KA) and the distance or the ion-size parameter (R or a°) are evaluated from these data. A better fit of the parameters was provided by the F78 equation which yielded KA and R values. The Λ0 and the KA values are found to increase with decrease in the dielectric constant of the medium and in a given solvent mixture they follow the order Et4NBr>n-Pr4NBr>n-Bu4NBr>n-Bu4NBPh4.
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