Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 85 , Issue 3
Showing 1-15 articles out of 15 articles from the selected issue
Award Accounts
The Chemical Society of Japan Award for 2010
  • Toshiaki Enoki, Kazuyuki Takai, Manabu Kiguchi
    2012 Volume 85 Issue 3 Pages 249-264
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: February 23, 2012
    JOURNALS FREE ACCESS
    Nanographene, nanosized fragments of graphene, has edge-shape-dependent electronic structures different from those of infinite size graphene. Around the zigzag-shaped edges of a nanographene sheet, a nonbonding edge state of π-electron origin is created, which is the origin of electronic and chemical activities of nanographene. In addition, the strongly spin-polarized edge state has localized spin, giving magnetic activity. We investigate the magnetic properties of nanoporous activated carbon fibers consisting of a three-dimensional disordered network of nanographite domains, each of which is a stack of 3–4 nanographene sheets, in relation to host–guest interaction. Chemically inert guest species such as water, organic solvent, or argon, physisorptively condensed into the nanopores mechanically compress the nanographite domains, resulting in high spin/low spin magnetic switching of the edge-state spins. The presence of an energy gap and the nanographene edges decorated by oxygen-containing functional groups make nanographene less amphoteric, modifying charge-transfer mechanisms in the host–guest interaction. HNO3 shows a two-step charge-transfer process. In Br adsorption, physisorbed Br species cooperate with charge-transfer Br species, giving an interesting interplay of charge transfer and magnetic switching phenomena. In the K adsorption, physisorbed K atoms form antiferromagnetic K clusters in the nanopores, while a portion of K species are responsible for charge transfer. The reaction with fluorine creates magnetic σ-dangling bond states, at the expense of the π-conjugated electron system. The interplay between the edge-state spins and the σ-dangling bond spins gives a variety of magnetism depending on the fluorine concentration.
    The edge of nanographene is electronically, magnetically, and chemically active due to the presence of nonbonding edge states. A variety of unconventional magnetic phenomena created upon host–guest interaction with nanographene and various guest molecules are reviewed. Fullsize Image
The Chemical Society of Japan Award for Young Chemists for 2010
  • Hiroshi Yabu
    2012 Volume 85 Issue 3 Pages 265-274
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: February 23, 2012
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    In this account, we review recent developments in the preparation of various functional and nanostructured polymer particles by precipitation-based methods. First, we present an overview of recent polymer particle preparation methods including methods for precipitation-based particle preparation. Next, we introduce the self-organized precipitation and its advantages. We discuss the morphological control of polymer particles based on the types of polymer materials used for particle preparation. We also introduce the preparation of organic–inorganic composite particles. Finally, we discuss the future outlook of nanostructured polymer particles.
    In this account, we review the recent developments in the precipitation-based polymer particle preparation methods and preparation of polymer particles by using self-organized precipitation (SORP), which is an emerging procedure in precipitation-based particle preparation methods. Fullsize Image
BCSJ Award Article
  • Jaya Tuteja, Shun Nishimura, Kohki Ebitani
    2012 Volume 85 Issue 3 Pages 275-281
    Published: March 15, 2012
    Released: March 15, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    One-pot synthesis of furans from various saccharides such as arabinose, rhamnose, and lactose were performed over solid acid and base catalysts. The combination of Amberlyst-15 and hydrotalcite catalysts showed successful activity for corresponding furans formation such as 2-furaldehyde (furfural), 5-hydroxymethyl-2-furaldehyde (HMF), and 5-methyl-2-furaldehyde (MF) via one-pot synthesis including isomerization and dehydration reactions. Moreover, the acid–base pair catalysts were also found to display excellent activity for the transformation from mixed-sources of sugars to furans. It was indicated that the isomerization of saccharides and successive dehydration in the one-pot synthesis of furans will be a great approach in a biorefinery.
    An efficient one-pot synthesis of furans from mono- and disaccharides, a major component of inedible, inexpensive lignocellulosic biomass was demostrated via solid acid and base catalysts under mild conditions. High yield of furans was obtained from their corresponding sugars and comparable yield of mixture of furans were achieved from mixed-sugars. The procedure in one-pot synthesis of furans involves isomerization and successive dehydration using solid acid and base catalysts will be a great approach for biorefinery. Fullsize Image
 
  • Shinsaku Fujita
    2012 Volume 85 Issue 3 Pages 282-304
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 08, 2012
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    The restricted-subduced-cycle-index (RSCI) method for symmetry-itemized enumeration of Kekulé structures has been developed as an extension of the unit-subduced-cycle-index (USCI) approach (S. Fujita, “Symmetry and Combinatorial Enumeration in Chemistry,” Springer-Verlag, 1991). In the RSCI method, such Kekulé structures are considered to be generated by edge substitution of a skeleton under a restricted condition that no selected edges have a common vertex. The restricted condition is formulated by means of the concept of territory indicators and territory discriminants, by which subduced cycle indices (SCIs) derived from unit subduced cycle indices (USCIs) are converted into restricted subduced cycle indices (RSCIs). The resulting RSCIs are used to evaluate marks (numbers of fixed points) in place of the SCIs used in the USCI approach, so that the numbers of Kekulé structures are calculated in a symmetry-itemized fashion. Moreover, the resulting data of enumeration are used to draw respective Kekulé structures by means of orbit indicators and edge indicators. The application of the RSCI method to fullerene C60 of Ih-symmetry is discussed in detail.
  • Daigoro Endo, Tomoyuki Akutagawa, Kazuya Kubo, Shin-ichiro Noro, Leroy ...
    2012 Volume 85 Issue 3 Pages 305-315
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    Supplementary material
    Single crystals formed from hydrogen-bonding supramolecular cations of o-aminoanilinium (HOPD+)–crown ethers, (HOPD+)([12]crown-4), (HOPD+)([15]crown-5), and (HOPD+)([18]crown-6), and one-electron-reduced [PMo12O40]4− Keggin-type clusters were synthesized. The crystal structures and dielectric responses of the three new compounds (HOPD+)4([12]crown-4)4[PMo12O40]4−·4CH3CN (1), (HOPD+)4([15]crown-5)4[PMo12O40]4− (2), and (HOPD+)4([18]crown-6)4[PMo12O40]4−·8CH3CN (3) were examined. The CH3CN molecules in salts 1 and 3 were included in zero-dimensional pores and one-dimensional channels, respectively; higher thermal stability was observed in the former lattice because of its extended hydrogen-bonding network. Large frequency- and temperature-dependent dielectric responses were confirmed in salts 2 and 3, whereas the dielectric response of salt 1 was quite small. The fixed orientation of HOPD+ because of the hydrogen-bonding network was consistent with the dielectric property of salt 1. In contrast, large magnitudes of dielectric responses in the temperature range above 280 K were observed for salt 3. Thermal motions of CH3CN molecules in the channel were the origin of such dielectric responses. In salt 2, the thermally activated coupled motion of the orthogonally arranged HOPD+ pair along the C–NH3+-axis with the potential energy barrier of ca. 80 kJ mol−1 resulted in large dielectric responses.
  • Yasuharu Hasegawa, Ilya D. Gridnev, Takao Ikariya
    2012 Volume 85 Issue 3 Pages 316-334
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: February 23, 2012
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    Supplementary material
    The mechanism of two enantioselective reactions, direct amination of α-cyanoacetates 3 with azodicarboxylates 4 and C–C bond formation reaction of α-cyanoacetates with acetylenic esters 6, catalyzed by chiral bifunctional Ir and Ru complexes, Cp*Ir[(S,S)-N-sulfonated dpen] 1 and Ru[(S,S)-N-sulfonated dpen](η6-arene) 2 (DPEN: 1,2-diphenylethylenediamine) was studied by NMR spectroscopic analysis combined with DFT analysis. Notably, these two reactions using the same chiral amide catalysts 1, 2 and pronucleophile, α-cyanoacetates 3 gave quantitatively the conjugate adducts bearing quaternary chiral carbon centers in excellent enantiomeric excess albeit with the opposite absolute configuration depending on the acceptor molecules 4 and 6. NMR investigation of the reactions between Ir complexes 1a1c with α-cyanoacetates 3 showed that a stereoselective deprotonation reaction takes place to give an equilibrium mixture of N-bound amine complexes 8 and 9, the former with intramolecular hydrogen bonding and the latter without it, respectively. Computational study revealed the full details of the mechanism of the asymmetric C–N and C–C bond forming reactions catalyzed by the chiral Ir catalyst 1b. In the C–N bond forming reaction, the dimethyl azodicarboxylate 4a undergoes productive bifunctional activation by a non-hydrogen-bonded N-bound complex 9b(re) resulting in the formation of the R-product through the energetically favorable transition state. On the other hand, the linear geometry of the acetylenic ester molecule 6 allows its bifunctional activation with both types of the N-bound complexes: 8b and 9b with and without the intramolecular hydrogen bond respectively. The hydrogen-bond stabilized transition state for the C–C bond formation leading to the S-enantiomer is significantly lower in energy than the corresponding non-hydrogen-bonded transition state leading to the R-enantiomer. Thus, chiral induction of these two reactions is determined by the structures of the acceptor molecules.
  • Hiromi Minemawari, Judy Fe F. Jose, Yukihiro Takahashi, Toshio Naito, ...
    2012 Volume 85 Issue 3 Pages 335-340
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: February 23, 2012
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    Supplementary material
    Electrolysis of ET in a mixed solvent of methanol/CHCl3 with bromide yielded (ET)3(Br3)5, in which an unusually high formal charge of ET5/3+ is achieved. ET forms a two-dimensional conducting sheet incorporating Br3. Despite the high formal charge of the ET cations, the strong electrostatic attractions between the ET cations and Br3 support aggregation of the ET cations, allowing sufficient π–π overlap for delocalization of the π-electrons. The crystal shows stable metallic behavior down to low temperatures, being consistent with the metallic band structure with two-dimensional Fermi surfaces and Pauli-like paramagnetism down to low temperatures. The lack of any indication of instability in the metallic phase due to correlation effects is considered to result from an ionic-crystal-like structure, in which the lattice is more resistant toward lattice deformation and/or shrinkage than in typical partially oxidized salts with low formal charges.
  • Keiichi Mitsuta
    2012 Volume 85 Issue 3 Pages 341-353
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    The rate constant, kS, for the reaction of scavengers, obtained from a competitive reaction system in which KO2 was used as a superoxide source, with superoxide has been reevaluated in electron spin resonance (ESR) spin-trapping studies. In consequence, it has been found that the local pH in a reaction field of our KO2 system was 12. As a result, the rate constants for the reaction of xanthine oxidase (XOD) with superoxide at pH 7.8 and 12 were established to be 2.1 × 106 and 8.0 × 105 M−1 s−1, respectively. On the basis of these values, discrepancies between reports in the literature have been examined, and it has been found that systematic errors appearing in values of the rate constant, kT, for the reaction of spin-trapping agents with superoxide due to variations in determination method had originated from omission of the superoxide-scavenging activity of XOD and that the errors could be explained almost completely quantitatively. For this reason, the kT values latterly reported by Allouch et al. are inferior to those formerly reported by Finkelstein et al. as reference values when the kS values are determined by the kinetic competition using these kT values.
  • Shinichi Mochizuki, Yumi Kamikawa, Koichi Nishina, Shota Fujii, Emi Ha ...
    2012 Volume 85 Issue 3 Pages 354-359
    Published: March 15, 2012
    Released: March 15, 2012
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    Gene therapy by introducing a foreign DNA into a cell with defective gene has been expected to treat various incurable diseases such as cancers, inherited diseases, and cardiovascular disease. Cationic lipids have been used as a carrier of therapeutic DNAs because they can form a complex with DNA and such a complex can be incorporated into cells and transport the bound DNA to cytosol. This complex is called lipoplex and categorized as a nonviral vector. We synthesized various kinds of cationic lipids with aromatic ring attached different hydrophilic groups, alkyl chain length and position of alkyl chains and evaluated their transfection efficiency. The lipids with primary amine and ethylenediamine-attached C12 at meta–meta position showed the highest transfection efficiencies, which reaches the same level as commercially available transfection reagent. The order of transfection efficiency in terms of alkyl chain length is follows: C12 ≫ C9 ≈ C18. The lipids with a primary amine showed better transfection efficiency than that with a quaternary ammonium salt. These results show that these cationic lipids with amine group attached aromatic structure can be used for novel transfection reagents.
  • Maaroof Zarei
    2012 Volume 85 Issue 3 Pages 360-368
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: February 23, 2012
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    An efficient one-pot synthesis of β-lactams by the reaction of imines with acetic acid derivatives in the presence of DMF and benzoyl chloride adduct, a cheap reagent, has been described. Optimization of solvents, temperature, and molar ratio of reagent was also performed. Several types of β-lactams including monocyclic, spirocyclic, N-alkyl, 3-butadienyl, and 3-electron-withdrawing group have been synthesized by this method in good to excellent yields. All steps of the reaction proceed at room temperature.
  • Koji Nemoto, Satoru Onozawa, Megumi Konno, Naoya Morohashi, Tetsutaro ...
    2012 Volume 85 Issue 3 Pages 369-371
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    Thiophenes and benzothiophenes bearing alkyl or aryl substituents at the 2- or 3-positions are successfully carboxylated with CO2 with aid of EtAlCl2 to give the corresponding 2- or 3-carboxylic acids in up to 90% yield.
  • Moriaki Hatakeyama, Takayoshi Hara, Nobuyuki Ichikuni, Shogo Shimazu
    2012 Volume 85 Issue 3 Pages 372-375
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    The structure of allophane heat-treated at 623, 773, and 973 K was characterized by 27Al cross-polarization magic-angle-spinning (CP-MAS) and 27Al multiple-quantum magic-angle-spinning (MQMAS) NMR. From these spectra, the structural change of allophane was observed over 623 K, i.e., the formation of five-coordinated Al from the original six-coordinated Al in allophane was confirmed after heat treatment. We concluded that Al atoms in the five-coordinated species have been formed by the OH elimination from six-coordinated Al in allophane. In addition, aluminosilicate layer deformation also took place to form silica and alumina thin layers separately. The results of 31P MAS NMR studies indicate the Lewis acid sites rather than Brønsted acid sites increased with a rise in the treatment temperature.
  • Si-Jia Hao, Kazuyuki Takai, V. L. Joseph Joly, Kazumichi Yokota, Manab ...
    2012 Volume 85 Issue 3 Pages 376-388
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    Magnetic properties of nanoporous carbon consisting of a 3D disordered network of nanographite domains are investigated in relation to the host–guest interaction with guest nitric acid molecules possessing significant oxidizability. An individual nanographite domain consists of a stack of 3–4 nanographene sheets, the edges of which have the localized spins of nonbonding edge states. The adsorption of HNO3 induces a two-step reduction in the edge-state spin concentration due to the charge-transfer interaction and is accompanied with the decomposition of HNO3 into the magnetic NO molecules, which are dimerized to form nonmagnetic (NO)2 with an enthalpy of ≈35 kJ mol−1 at low temperatures. The electronic activities of the edge state play an important role in the decomposition effect, and the NO spins are coupled to the edge-state spins through exchange interaction. The NO molecules can be removed by vacuum heat-treatment above 200 °C, however the nitrogen-containing functional groups strongly incorporated on the nanographene sheets cannot be removed even at such high temperature.
  • Takayuki Hoshi, Byungchan Bae, Masahiro Watanabe, Kenji Miyatake
    2012 Volume 85 Issue 3 Pages 389-396
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    A new series of poly(arylene ether sulfone) multiblock copolymers were synthesized by polycondensation of linear and rigid hydrophobic and densely sulfonated hydrophilic oligomers. Thin membranes were prepared therefrom by solution casting and their properties were compared with those of Nafion and other poly(arylene ether sulfone) multiblock copolymers containing perfluorinated biphenylene moieties. The membranes showed good water affinity, high proton conductivity, low hydrogen and oxygen permeability, high mechanical strength, and reasonable oxidative stability. These properties are attractive as an electrolyte for polymer electrolyte membrane fuel cells. It was found that the perfluorinated biphenylene moieties as connecting groups for hydrophilic and hydrophobic blocks affected only slightly the properties of poly(arylene ether sulfone) multiblock copolymer membranes.
  • Tetsuhiro Katsumata, Mamoru Nakashima, Yoshiyuki Inaguma, Takao Tsurui
    2012 Volume 85 Issue 3 Pages 397-399
    Published: March 15, 2012
    Released: March 15, 2012
    [Advance publication] Released: March 03, 2012
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    New perovskite-type oxyfluoride, PbMnO2F was synthesized under 4–7 GPa at 1000 °C. As a result of X-ray and electron diffractions, the compound was determined to have tetragonal perovskite structure with a × a × 4c super structure where a and c are the lattice parameters of the perovskite subcell. The tetragonality, c/a, attained maximum, c/a = 1.100, for PbMnO2F synthesized under 4 GPa.
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