Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 75 , Issue 12
Showing 1-23 articles out of 23 articles from the selected issue
  • Makoto Komiyama, Akinori Kuzuya, Ryo Mizoguchi
    Type: Accounts
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2547-2554
    Published: 2002
    Released: December 15, 2002
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    New types of RNA cutters for site-selective scission are prepared by combining metal ions with oligonucleotides bearing an acridine. Both lanthanide(III) ions and various divalent metal ions (e.g., Zn(II), Mn(II), and Mg(II)) are used without being bound to any sequence-recognizing moiety. The modified oligonucleotide forms a hetero-duplex with the RNA, and activates the phosphodiester linkages in front of the acridine. As a result, these linkages are preferentially hydrolyzed over the others, even though the metal ions are not fixed anywhere. The scission is efficient under physiological conditions, irrespective of the sequence at the target site. Site-selective RNA scission is also accomplished by combining an oligonucleotide bearing an acridine at its terminus, another unmodified oligonucleotide, and a metal ion. In the proposed mechanism, the acridine pushes the unpaired ribonucleotide out of the hetero-duplex and changes the conformation of RNA at the target site for the sequence-selective activation.
  • Hiroshi Yamataka, Misako Aida
    Type: Accounts
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2555-2569
    Published: 2002
    Released: December 15, 2002
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    Ab initio direct-MD simulations and combined QM/MM computations are the theoretical methods that are expected to play an important role in the study of organic reaction mechanisms in the near future. This account reviews recent achievements with these methods in mechanistic studies of organic reactions. In particular the focus is placed on proton transfer, SN1, SN2, and SN2/ET borderline reactions as illustrative examples. The direct-MD simulations revealed the importance of dynamics in controlling the reaction path, which can often be different from the minimum energy path on the potential energy surface. It was also demonstrated that the QM/MM computations could be a promising method to analyze reactions in solution.
  • Shinobu Tsutsui, Kenkichi Sakamoto, Keisuke Ebata, Chizuko Kabuto, Hid ...
    Type: Headline
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2571-2577
    Published: 2002
    Released: December 15, 2002
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    2,3,5,6-Tetrasilyl- and 2,3,5,6-tetragermyl-1,4-benzoquinones were obtained by oxidation of the corresponding 1,4-dimetaloxybenzene derivatives with pyridinium chlorochromate. X-ray crystallographic analysis revealed that the quinone ring of 2,3,5,6-tetrakis(trimethylsilyl)-1,4-benzoquinone (1a) was distorted into a chair form. The deformed quinone ring allowed a σ(Cquinone-Si)–π* electronic transition in 1a. Photolysis of 1a resulted in an isomerization, creating a ketene derivative, 4-carbonyl-2,3,5,5-tetrakis(trimethylsilyl)-2-cyclopenten-1-one.
  • Yasuo Kameda, Hisashi Naganuma, Kazuhide Mochiduki, Masahiro Imano, Ta ...
    Type: Article
    Subject area: TP
    2002 Volume 75 Issue 12 Pages 2579-2585
    Published: 2002
    Released: December 15, 2002
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    Neutron diffraction measurements with 14N/15N and H/D isotopic substitution methods have been carried out on aqueous 15 mol% urea solutions, in order to obtain information on the hydration structure of the amino group within the urea molecule in concentrated aqueous solutions. The observed first-order difference function, 0HΔN(Q), and the N–H partial structure factor, aNH(Q), were analyzed by the least squares fitting procedure. The nearest neighbor N···O and N···H distances were obtained to be 2.92(1) Å and 3.42(1) Å, respectively. The average hydration number per one amino group was determined to be 2.0(1). The tilt angle between the N–H···O axis and the molecular plane of the hydrogen bonded water molecule is estimated to be 51(5)°.
  • Thomas Koop
    Type: Short Articles
    Subject area: TP
    2002 Volume 75 Issue 12 Pages 2587-2588
    Published: 2002
    Released: December 15, 2002
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    A thermodynamic derivation is presented to show that the water activity of aqueous solutions in equilibrium with ice is independent of the nature of the solute. In addition, recent data of ice nucleation in MgCl2 solutions are compared to water-activity-based ice nucleation theory.
  • Takahiro Yoshikawa, Tomoyuki Nakamura, Kazuyuki Kuroda, Makoto Ogawa
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2589-2594
    Published: 2002
    Released: December 15, 2002
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    The adsorption of methylene blue onto aluminum-containing mesoporous silica films was investigated. The mesoporous silica films were synthesized by rapid solvent evaporation method using tetramethoxysilane, aluminum tri(s-butoxide), and trimethyloctadecylammonium chloride as a silica source, alumina source and supramolecular template, respectively. Methylene blue was adsorbed effectively on the mesoporous silica films from solutions. The adsorbed amount increased with the increase in the aluminum content of the films, indicating that the added aluminum generated the adsorption sites (probably acidic sites) for methylene blue adsorption. The mesopore surface is not strongly acidic because the protonation of methylene blue did not occur. Adsorbed methylene blue exists as monomers in the mesopore. The dehydration of the films resulted in the aggregation of methylene blue, as evidenced by the visible absorption spectra.
  • Masahiro Mikuriya, Kenichi Minowa, Ryoji Nukada
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2595-2607
    Published: 2002
    Released: December 15, 2002
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    Alkoxo-bridged copper(II) complexes with N,N′-bis(1-methyl-3-hydroxy-3-phenyl-2-propen-1-ylidene)-1,3-diamino-2-propanol (H3bzacpro), N,N′-bis(1-methyl-3-hydroxy-3-phenyl-2-propen-1-ylidene)-1,4-diamino-2-butanol (H3bzacbu), and N,N′-bis(1-methyl-3-hydroxy-3-phenyl-2-propen-1-ylidene)-1,5-diamino-3-pentanol (H3bzacpen), [Cu2(bzacpro)(CH3CO2)] (1), [Cu4(bzacpro)2(C2H5O)2] (2), [Cu2(bzacbu)(CH3CO2)] (3), [Cu4(bzacbu)2(CH3O)2] (4), [Cu4(bzacpen)2(CH3CO2)2] (5), and [Cu4(bzacpen)2O]·H2O (6) have been synthesized and characterized by measurements of the infrared and electronic spectra, and the magnetic susceptibilities. Single-crystal X-ray analyses revealed that 1 and 3 are dinuclear copper(II) complexes having a dinuclear core bridged by an alkoxo-oxygen atom of bzacpro or bzacbu and acetato-oxygen atoms, whereas 2, 4, 5, and 6 are tetranuclear copper(II) complexes composed of μ-alkoxo(bzacpro)-μ-ethoxo-, μ-alkoxo(bzacbu)-μ-methoxo-, μ-alkoxo(bzacpen)-μ-acetato-, and μ-alkoxo(bzacpen)-μ-oxo-bridged units, respectively. Magnetic-susceptibility data show that an antiferromagnetic interaction is operative within the dinuclear or tetranuclear core in 13, 5 and 6, whereas a ferromagnetic coupling is operative in 4. The crystal structures of the three Schiff-base ligands have also been elucidated.
  • Wenguo Wang, Chengbing Ma, Xiaofeng Zhang, Changneng Chen, Qiutian Liu ...
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2609-2614
    Published: 2002
    Released: December 15, 2002
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    Two catena manganese carboxylato complexes [{Mn[m-C6H4(COO)2](C5H5N)2}n] (1) and [{Mn(3-C5H4NCO-O)2}n] (2) were synthesized and structurally characterized. Isophthalate together with pyridine as a capping ligand leads to a 1-D alternating chain structure of complex 1, while 3-pyridinecarboxylate (also known as nicotinate) results in a 3-D network of complex 2, implying an effect of the ligand on the dimensionality of the extended structure. Stretching vibration differences, Δ(νasνs) < 200 cm−1, for the COO groups of both complexes were observed to be consistent with the bridging and chelating coordination modes. The variable-temperature conductance of 1 displays a semiconductor feature. Magnetic exchange interactions were analyzed using models composed of Mn2(μ-COO)2 and Mn2(μ-acidate)2 moieties, exhibiting an antiferromagnetic coupling behavior for each complex through Mn2(μ-COO)2 moieties. The magnetic interaction in the Mn2(μ-acidate)2 moieties is negligible.
  • Takayuki Horiuchi, Nobuhiko Iki, Hiromi Oka, Sotaro Miyano
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2615-2619
    Published: 2002
    Released: December 15, 2002
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    The energy-transfer luminescence of complexes of Tb3+ with calix- (CAS), thiacalix- (TCAS), and sulfonylcalix[4]arene-p-tetrasulfonates (SO2CAS), in which four p-phenolsulfonates are jointed by –CH2–, –S–, and –SO2–, respectively, was applied to an ultratrace determination of the Tb3+ ion. Based on the complexation behavior of each calix ligand, a determination procedure was established. A time-resolved measurement was conveniently employed to separate the background fluorescence from the luminescence of the calix-Tb3+ complexes. An improved sensitivity was attained by sulfur-bridged calixes, TCAS and SO2CAS, as compared to CAS, owing to the photophysical properties of the Tb3+-complexes. The detection limits for Tb3+ ion by CAS, TCAS, and SO2CAS ligands were estimated to be 8.2×10−10 mol dm−3 (131 ppt), 2.0 × 10−10 mol dm−3 (32 ppt), and 2.3 × 10−10 mol dm−3 (37 ppt) at S/N = 3, respectively. In terms of the selectivity, the effect of diverse coexisting ions on the luminescence intensity of the Tb3+ complexes was studied. The luminescence of the TCAS complex was interfered by the presence of a 5-fold amount of other lanthanide ions, while that of the SO2CAS complex was more tolerant for those metal ions, allowing the presence of as much as 50 to 100-fold amounts. Also, 10 to 1500-fold amounts of other common ions were tolerated by using SO2CAS. Thus, SO2CAS was proved to be a practical reagent for determining the Tb3+ ion at the sub-ppb level.
  • Tenpei Akasaka, Motohiro Nakano, Hatsue Tamura, Gen-etsu Matsubayashi
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2621-2628
    Published: 2002
    Released: December 15, 2002
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    [NMe4]2[Sn(C3S5)3], [NBun4]2[Sn(C3S5)3], [NBun4]2[Sn(C8H4S8)3], [NEt4][Sn(Bun)(C8H4S8)2] and [NBun4][Sn(Ph)(C8H4S8)2] [C3S52− = 4,5-disulfanyl-1,3-dithiole-2-thionate(2−) ; C8H4S82− = 2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-ditholate(2−)] were prepared by reactions of Na2[C3S5] or Na2[C8H4S8] with SnCl4·5H2O, Sn(Bun)Cl3 and Sn(Ph)Cl3 in EtOH. [NBun4]2[Sn(C8H4S8)3] was oxidized by iodine or TCNQ in DMF/CH2Cl2 to give [Sn(C8H4S8)3], which exhibited an electrical conductivity of 3.2 × 10−2 S cm−1 (compacted pellet at room temperature). [NBun4]2[Sn(C3S5)3], [NEt4][Sn(Bun)(C8H4S8)2] and [NBun4][Sn(Ph)(C8H4S8)2] were oxidized by iodine or TCNQ in acetone or in DMF to afford (C3S5)2 and (C8H4S8)n. Crystal structures of [NMe4]2[Sn(C3S5)3], [NBun4]2[Sn(C3S5)3], [NBun4][Sn(Ph)(C8H4S8)2] and (C3S5)2 were determined by X-ray crystallography.
  • Masashi Hojo, Tadaharu Ueda, Akihiko Inoue
    Type: Article
    Subject area: AI
    2002 Volume 75 Issue 12 Pages 2629-2636
    Published: 2002
    Released: December 15, 2002
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    In acetonitrile, chelate formation between alkaline earth metal ions and 1-(2-pyridylazo)-2-naphthol (PAN = Hpan) in both the absence and presence of CH3SO3H and 1,1,3,3-tetramethylguanidine (1,1,3,3-TMG) was examined by means of UV-visible absorption and 1H NMR spectroscopy at room temperature. Upon the addition of 0.01 mol dm−3 or more of Mg(ClO4)2 to a 5.0 × 10−4 mol dm−3 PAN–MeCN solution, the solution color turned from yellow to red. The appearance of a new absorption band with two peaks at 500 and 535 nm indicated 1 : 1 chelate formation between Mg2+ and PAN; the equilibrium constant was evaluated to be 2.5 × 10−3 for the following reaction: Hpan + Mg2+ Mg(pan)+ + H+. The presence of an equivalent amount of the base, 1,1,3,3-TMG, enhanced the chelate formation reaction, while that of the acid (CH3SO3H) depressed the reaction remarkably. The 1H NMR results verified the above reaction scheme for Mg2+ and PAN. The interaction between the metal ions and PAN in acetonitrile decreased as Mg2+ > Ca2+ ≅ Sr2+ >> Ba2+. In the absence of the base, strange to say, direct chelate formation between Mg2+ and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) was much less than that for PAN; however, conversely, it was greater in the presence of a ten-fold amount of the base. The additional interaction between the second Mg2+ and the N-atom of the diethylamino group in 5-Br-PADAP was concluded to depress the chelate formation of the first Mg2+. The enhancement of the acidity of CH3SO3H (considerably weak acid in MeCN) by the addition of Mg(ClO4)2 inhibited not only the chelation, but also another interaction between Mg2+ and 5-Br-PADAP.
  • Yuefa Gong, Katsuya Kato, Hiroshi Kimoto
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2637-2645
    Published: 2002
    Released: December 15, 2002
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    The aromatic substitution of three representative N-alkyl trifluoromethyl imines 1ac (R: a, benzyl; b, benzhydryl; c, methyl), obtained from primary alkyl amines and trifluoroacetaldehyde ethyl hemiacetal, was used to investigate the preparation of 1-aryl-2,2,2-trifluoroethylamines. In the presence of BF3·OEt2, the reaction of imine 1 with various aromatic compounds proceeded smoothly at room temperature, giving N-alkyl-1-aryl-2,2,2-trifluoroethylamines in moderate-to-high yields. Moreover, successful regioselective removal of N-benzyl and N-benzhydryl groups was achieved by hydrolysis in hydrochloric acid or by palladium-catalyzed hydrogenolysis.
  • Takeshi Kimura, Susumu Mizusawa, Akira Yoneshima, Shinya Ito, Kazuhiko ...
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2647-2653
    Published: 2002
    Released: December 15, 2002
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    6,9-Diethyl-1,2,3,4,5-benzopentathiepin (1) and 4,7-diethyl-1,2,3-benzotrithiole (2) were photolyzed by a 100 W high-pressure mercury lamp in dichloromethane under an argon atmosphere. These reactions produced 1,4,6,9-tetraethylthianthrene (3) by way of desulfurization, dimerization, and ring contraction reactions. Application of the photolysis was possible to 4,8-diethylbenzo[1,2-d : 4,5-d′]di[1,2,3]trithiole (6) and 4,7-diethyl-5,6-ethylenedithio-1,2,3-benzotrithiole (7). These reactions provided 1,4,6,9-tetraethyl[4,5-b : 4′,5′-i]di[1,2,3]trithiolothianthrene (8) with two trithiole rings and 1,4,6,9-tetraethyl-2,3 : 7,8-bis(ethylenedithio)thianthrene (10) with two ethylenedithio groups on both sides of thianthrene, respectively. The photolysis of 1,4,6,9-tetraethyl-7,8-bis(octylthio)[1,2,3]trithiolo[4,5-b]thianthrene (12) and 1,4,6,9-tetraethyl-7,8-ethylenedithio[1,2,3]trithiolo[4,5-b]thianthrene (15) gave higher related derivatives of thianthrene, 1,4,6,8,10,13,15,17-octaethyl-2,3,11,12-tetrakis(octylthio)-5,7,9,14,16,18-hexathiaheptacene (14) and 1,4,6,8,10,13,15,17-octaethyl-2,3 : 11,12-bis(ethylenedithio)-5,7,9,14,16,18-hexathiaheptacene (16), respectively. The electrochemical property of each thianthrene derivative was verified by cyclic voltammetry using silver nitrate as a reference electrode.
  • Masaru Kimura, Hirofumi Mitekura, Tomoko No, Kazuyoshi Suzuki
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2655-2660
    Published: 2002
    Released: December 15, 2002
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    In order to evaluate the role of a substituent in sensitivity enhancement of meso-substituted trimethine cyanine dyes as sensitizers for photo-polymerization, we prepared a series of cyanine dyes, 3-ethyl-2-{3-(3-ethyl-3H-2-benzothiazolylidene)-2-[2-(4 or 3-X-phenyl)ethenyl]-1-propenyl} benzothiazolium iodide, 1ak (a: X = p-NMe2, b: X = p-OMe, c: X = p-CH3, d: X = H, e: X = p-Cl, f: X = p-CF3, g: X = p-CN, h: X = p-NO2, i: X = m-OMe, j: X = m-CH3, k: X = m-Cl). The sensitivity for the photo-polymerization tends to be greater for substituents with greater electron-donating ability. In the series, the sensitivity of dye 1a was 2.1 mJ/cm2 higher than the other sensitivities. The sensitivities of dye 2 having a 2-(9-julolidinyl)ethenyl group was high: 1.5 mJ/cm2 and that of dye 3 having a 2-(9-julolidinyl)-1-methylethenyl group was the highest: 0.7 mJ/cm2, among all dyes tested here.
  • Shinobu Tsutsui, Kenkichi Sakamoto, Keisuke Ebata, Chizuko Kabuto, Hid ...
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2661-2665
    Published: 2002
    Released: December 15, 2002
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    We synthesized 5-chloro- and 5-bromo-substituted 2-(pentamethyldisilanyl)-1,4-benzoquinones 1a and 1b, respectively. Their electronic absorption spectra showed significant intramolecular charge-transfer interaction between disilane and 1,4-benzoquinone moieties. The intramolecular σ(SiSi)–π* transition energies of 1a and 1b were lower than that of 2-(pentamethyldisilanyl)-5-t-butyl-1,4-benzoquinone (1c). X-ray crystallographic analysis of chloro-substituted derivative 1a revealed that the angle between the Si–Si bond and the quinone ring was 74° and also that the structure of 1a in the solid state was also advantageous for CT interaction. Photoreaction of 1a and 1b gave α-sila-m-quinonemethide derivatives 3a and 3b, respectively, which were trapped by acetone. Matrix isolation of 3a, 3b, and their 2-methyltetrahydrofuran-complexes were accomplished in glass matrixes.
  • Shinji Toyota, Mitsuhiro Asakura, Tatsuya Sakaue
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2667-2671
    Published: 2002
    Released: December 15, 2002
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    The title carbonyl compounds bearing a 4,4-diphenyl-1,3,2-dioxaborolan-2-yl group at the ortho position were prepared to compare the Lewis basicity of carbonyl-oxygen atoms. In the benzoyl and formyl compounds, the intramolecular C=O···B interactions are so weak that no significant changes were observed in the 13C and 11B NMR and IR spectra compared with the reference compounds. For the acetyl compound, the C=O stretching absorption was shifted to lower wavenumber by 18 cm−1 in the IR spectrum because of the coordination. The interaction energy could be estimated to be ca. 27 kJ mol−1 by the variable temperature 1H NMR measurement. These substituent effects are discussed from the viewpoints of Lewis basicity and the conformational stability of the carbonyl moieties with the assistance of the DFT calculations.
  • Kensuke Naka, Takashi Uemura, Yoshiki Chujo
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2673-2679
    Published: 2002
    Released: December 15, 2002
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    New polymers containing an intramolecular charge-transfer (ICT) structure (pyridinium–dithiafulvene–pyridinium) in the main chain were prepared. UV–vis measurements of the polymers suggested that conjugative effects occur through saturated polymethylene chains, and that such effects are enhanced as the length of the spacer polymethylene chain decreases. Polyviologens showed small but similar conjugations in their UV–vis measurements. A PM3 calculation of 1,1′-(1,2-ethanediyl)bis(pyridinium) suggested that low-lying LUMO resulting from an interaction between the σ* of the ethylene unit and π* of the pyridinium moiety affords the conjugative effect. The PM3 calculations and the UV–vis results show that the incorporation of the ICT moiety in the polymeric framework increases the conjugative effect through the polymethylene chains. The redox and conducting properties of the ICT polymers were also investigated. Both studies gave some implications of the conjugative effects of the polymers.
  • Akiko Tsuchida, Teruaki Hasegawa, Kazukiyo Kobayashi, Chiyo Yamamoto, ...
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2681-2685
    Published: 2002
    Released: December 15, 2002
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    3,5-Dimethylphenylcarbamate derivatives of α-/β-glucose and α-/β-galactose-carrying helical poly(phenyl isocyanide)s were used as chiral stationary phases (CSPs) for HPLC to estimate their chiral recognition abilities. CD spectroscopy suggested that the helix sense in these rigid helical polymers may be regulated by the chirality of the α- or β-anomeric center of the sugar moieties. Some 10 different types of racemates with functional groups were completely or partially resolved depending on the stereostructure of the pendant sugars. The enhanced chiral recognition ability is attributable to the three-dimensionally regulated sugar arrays along the helical backbone; that is, the CSP of the α-glucose-carrying helical poly(phenyl isocyanide) exhibited more effective enantioseparation than that of the corresponding flexible poly(N-phenylacrylamide). The CSPs of the galactose-carrying poly(phenyl isocyanide)s showed the resolving ability for broader racemates than those of the glucose-type poly(phenyl isocyanide)s. Especially, the CSP of the α-galactose-carrying poly(phenyl isocyanide) separated the largest number of racemates.
  • Shin-ichi Usugi, Hideki Yorimitsu, Hiroshi Shinokubo, Koichiro Oshima
    Type: Article
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2687-2690
    Published: 2002
    Released: December 15, 2002
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    Treatment of terminal acetylenes with butyllithium, followed by an addition of gallium trichloride, afforded the corresponding alkynylgallium reagents. The reaction of the resulting alkynylgallium with α-halo carbonyl compounds in the presence of triethylborane as a radical initiator provided β,γ-acetylenic carbonyl compounds in good yields.
  • Giorgos Athanasellis, Efstathios Gavrielatos, Olga Igglessi-Markopoulo ...
    Type: Short Articles
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2691-2692
    Published: 2002
    Released: December 15, 2002
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    A novel one-pot synthetic route to 4-acetylamino-2-cyano-3-hydroxybut-2-enoates in good yields (63–71%) is reported. An HPLC analysis of these compounds showed very good enantiomeric excesses (90–94%), justifying the success of our methodology to maintain the stereochemical integrity of the starting materials used.
  • Naoki Kise, Ryosuke Mimura, Nasuo Ueda
    Type: Short Articles
    Subject area: OB
    2002 Volume 75 Issue 12 Pages 2693-2694
    Published: 2002
    Released: December 15, 2002
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    The constant-current electroreduction of 1,2-bis(bromomethyl)benzenes with dienophiles in NH4NO3–MeOH gave Diels–Alder cycloadducts in moderate-to-good yields.
  • Tsutomu Osawa, Nobuyo Ozaki, Tadao Harada, Osamu Takayasu
    Type: Short Articles
    Subject area: AM
    2002 Volume 75 Issue 12 Pages 2695-2696
    Published: 2002
    Released: December 15, 2002
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    The enantio-differentiating hydrogenation of 2-octanone was carried out over a tartaric acid-modified reduced nickel catalyst. It was shown that the in situ modification of the Ni surface was available for the hydrogenation of 2-octanone in the presence of a large amount of pivalic acid in the reaction media. An optical yield of 74% was attained with the in situ modified reduced Ni catalyst.
  • Yuki Fujiwara, Yutaka Amao
    Type: Short Articles
    Subject area: AM
    2002 Volume 75 Issue 12 Pages 2697-2698
    Published: 2002
    Released: December 15, 2002
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    Controlling the oxygen-sensitivity of optical sensor using layers of 1-pyrenedecanoic acid and myristic acid co-chemisorbed onto anodic oxidized aluminium plate was attempted. The oxygen-sensitivity was controlled by varying the molar ratio of myristic acid to 1-pyrenedecanoic acid.
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