Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 83 , Issue 3
Showing 1-12 articles out of 12 articles from the selected issue
Award Accounts
The Chemical Society of Japan Award for Young Chemists for 2007
  • Hiroto Yoshida, Joji Ohshita, Atsutaka Kunai
    2010 Volume 83 Issue 3 Pages 199-219
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 18, 2010
    JOURNALS FREE ACCESS
    A useful synthetic method for building up multisubstituted arenes of structural complexity and diversity by use of aromatic reactive intermediates is described. Regardless of the transient character arising from a highly strained carbon–carbon triple bond, arynes have been found to undergo facile insertion into an element–element σ-bond and three-component coupling reactions. In addition, ortho-quinone methides and ortho-quinodimethanes have also been demonstrated to be convertible into multisubstituted arenes by utilizing their exo-dienyl moieties.
    Direct synthesis of diverse multisubstituted arenes and benzo-annulated heterocycles based upon new transformations using such aromatic reactive intermediates as arynes, ortho-quinone methides, and ortho-quinodimethanes is described in this account. Fullsize Image
BCSJ Award Article
  • Takeharu Ishikawa, Toshiaki Shimasaki, Haruo Akashi, Tetsuo Iwanaga, S ...
    2010 Volume 83 Issue 3 Pages 220-232
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
    JOURNALS FREE ACCESS
    A cyclic arylene–ethynylene tetramer with a 1,5-anthrylene unit and a cramp moiety consisting of three anthrylene units and its derivatives with a 1,4-phenylene, 1,5-naphthylene, or 2,6-di-t-butyl-1,5-naphthylene unit were synthesized by macrocyclization with Sonogashira coupling. Except for the 1,4-phenylene compound, these cyclic compounds take the chiral C2 structure with parallel orientation of the two arylene units, as revealed by X-ray analysis and DFT calculation at the M05/3-21G level. The enantiomers of 1,5-anthrylene and 2,6-di-t-butyl-1,5-naphthylene compounds were resolved by chiral HPLC and their rotational barriers were determined to be 114 and >146 kJ mol−1, respectively, by classical kinetics. These high barriers are in contrast to the facile racemization or topomerization in the other compounds. These kinetic data of the rotation of arylene units about the acetylene axes are discussed in terms of steric hindrance based on molecular structures. The electronic spectra of the cyclic compounds and the chiroptical properties of the resolved samples were also measured.
    The rotation of the crank anthrylene group about acetylene linkers was so restricted that the enantiomers of the following cyclic tetramer were resolved by chiral HPLC. The structural and spectroscopic features of this compound are compared with another three derivatives having different crank moieties. Fullsize Image
  • Mohammad Hossein Fatemi, Hanieh Malekzadeh
    2010 Volume 83 Issue 3 Pages 233-245
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    The purpose of this study was to develop the structure–toxicity relationships for a large group of organic compounds including 392 substituted benzenes to the ciliate Tetrahymena pyriformis (Log(IGC50)−1) using interpretable molecular descriptors. These descriptors were calculated using DRAGON and CODESSA software. Multiple linear regression and artificial neural network methods were used as linear and nonlinear feature-mapping techniques. The best obtained model was derived by MLR with seven descriptors which are: the molecular weight, the radial distribution function, the Kier shape index, the 26th component of atom-centered descriptors type of R–CX–R, the topographic electronic index, the H atoms attached to CO groups, the 24th component of atom-centered descriptors of R–CH–R. These descriptors can encode different features of molecules which are responsible for their steric, electronic, and lipophilicity interactions. The best obtained model had statistics of R2 = 0.822, F = 1386.806, and SE = 0.312 for training and R2 = 0.815, F = 361.384, and SE = 0.337 for prediction. The presented model shows better statistical parameters in comparison with a previous model. The reliability of the model was evaluated by using the leave-many-out cross-validation method (Q2 = 0.819 and SPRESS = 0.32) as well as by y-scrambling.
  • Keishi Ohara, Takashi Origuchi, Shin-ichi Nagaoka
    2010 Volume 83 Issue 3 Pages 246-253
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    The singlet oxygen (1O2) behavior in emulsions dispersing natural vitamin E (VE) (α-, β-, γ-, and δ-tocopherols) was investigated by measuring time-profiles of 1O2 phosphorescence. The 1O2 rise and decay dynamics noticeably reflected the existence of VE oil-droplets. The decay rate constant (kd) in the α-tocopherol emulsion decreased with increase of VE concentration ([VE]), and became roughly constant in [VE] ≥ 5 × 10−4 M. This kd behavior correlated to the oil-droplet diameter measured by dynamic light scattering. The droplet diameter increased rapidly from 270 to 430 nm with increase of [VE], and reached the limit for dispersing in [VE] ≥ 5 × 10−4 M. This result means that the 1O2 surroundings became more hydrophobic with increase of droplet size. On the other hand, in the emulsions dispersing tocopherols other than α-tocopherol, the kd values were roughly constant, indicating that the oil-droplets did not contribute to 1O2 quenching. The droplet diameter in the δ-tocopherol emulsion was around 212–243 nm and was much smaller than that in the α-tocopherol emulsion. The peculiar results observed in the α-tocopherol emulsion should be due to the large hydrophobicity of α-tocopherol which has two methyl-groups neighboring the OH group.
  • Paul H. Kasai
    2010 Volume 83 Issue 3 Pages 254-260
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    While examining PFPE (perfluoropolyether)-based disk lubricants, extra lability was suspected for a hydrogen-bonded pair of hydroxy end-groups in the presence of a nucleophile (electron donor). Plausible reaction sequences upon electron capture of hydrogen-bonded methanol dimer, hydrogen-bonded ethanol dimer, and 1,2-propanediol were first examined by a molecular dynamics method based on the potential given by a semiempirical SCF molecular orbital calculation, and subsequently by matrix isolation ESR spectroscopy. In the latter experimental study, alcohol dimer anions were generated by co-trapping Na atoms and alcohol molecules in argon matrices and inducing electron transfer by photo-irradiation. In the cases of methanol and ethanol dimers, the molecular dynamics study predicted that on capture of an electron, the hydroxy hydrogen of the acceptor side would cleave as an atom, and then abstract a hydrogen atom from the nearest carbon of the proton donating alcohol. For 1,2-propanediol anion, the molecular dynamics study predicted C1–C2 bond scission followed by abstraction of the C2 hydroxy hydrogen by the C1 radical fragment. The matrix isolation ESR study revealed generation of radicals upon photo-irradiation when the alcohol concentration was sufficiently high to warrant the presence of dimers. The spectral patterns thus observed were totally consistent with the radical products predicted by the molecular dynamics calculations.
  • Satoaki Ikeuchi, Yasuhisa Yamamura, Yuji Yoshida, Minoru Mitsumi, Kosh ...
    2010 Volume 83 Issue 3 Pages 261-266
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    Heat capacity of a mixed-valence complex having a one-dimensional chain structure, [{Ni2(n-BuCS2)4}I] (n-Bu = butyl group), was measured between 10 and 325 K by adiabatic calorimetry. Anomalies due to phase transitions were detected around 135 and 260 K. The anomaly around 260 K was of multiple-peaks. The excess entropy acquired below the phase transition around 260 K is much smaller than the simple estimate based on the structural disorder found in the crystal structure, implying the presence of motional correlation in dynamics of n-BuCS2 ligands. Through the comparison with the corresponding Pt complex, [{Pt2(n-BuCS2)4}I], the phase transition around 135 K is also discussed in relation to the absence in the present complex of a spin-Peierls transition observed in other members of Ni complexes with similar chain structures.
  • Haruto Fujioka, Sayuri Kishida, Takashi Ishizu, Motoo Shiro, Eiji Kino ...
    2010 Volume 83 Issue 3 Pages 267-272
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    A dinuclear zinc(II) complex, m,m-bis(Zn2+–cyclen) was synthesized as a novel host molecule for a malonate dianion. The dizinc(II) complex has two zinc(II)–cyclen moieties (cyclen = 1,4,7,10-tetraazacyclododecane) connected through two m-xylene bridges. The 1:1 association constant of log K (K = {[malonate-bound m,m-bis(Zn2+–cyclen)]/[m,m-bis(Zn2+–cyclen)][malonate]}/M−1) was determined to be 3.6 by potentiometric pH titration at 25 °C with I = 0.10 M (NaNO3) in aqueous solution. The H/D exchange reaction of methylene hydrogen atoms of malonate dianion was accelerated by m,m-bis(Zn2+–cyclen) in D2O. The half-life was determined to be 80 min for a 1:1 mixture (2 mM) of malonate and m,m-bis(Zn2+–cyclen) at 25 °C and pD 7. From an aqueous solution of equimolar malonate and m,m-bis(Zn2+–cyclen) however, a cyclic 2:2 malonate/m,m-bis(Zn2+–cyclen) complex was isolated. The structure was confirmed by X-ray crystallography.
  • Koji Nakano, Yosuke Katsumi, Nobuaki Soh, Toshihiko Imato
    2010 Volume 83 Issue 3 Pages 273-275
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 18, 2010
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    A single-molecule strategy using atomic force microscopy has simply yet robustly probed an intercalation binding related specific structural relaxation of covalently closed circular pBR322 DNA as well as double-strand elongation in its linear form by taking advantage of a new psoralen derivative, N,N,N-trimethyl-1-(2,5,9-trimethyl-7-oxo-7H-furo[3,2-g]chromen-3-yl)methanaminium chloride, that covalently binds to DNA through a photo-crosslinking reaction.
  • Keiko Komori-Orisaku, Kazuma Hoshino, Shinya Yamashita, Yoshihiro Koid ...
    2010 Volume 83 Issue 3 Pages 276-278
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    Solvent-mediated structural transformation of {[Cu(4,4′-bpy)2(OTf)2]·2CH3CN}n coordination polymer (CP) was crystallographically characterized and confirmed the formation of infinite linear water networks that bind metal centers through the interplay of coordination and hydrogen bonding of water molecules.
  • Shoji Akai, Hidehito Seki, Naoki Sugita, Tomokazu Kogure, Naoki Nishiz ...
    2010 Volume 83 Issue 3 Pages 279-287
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    Total synthesis of (−)-tetrodotoxin (TTX) from D-glucose is described. As a critical transformation step for synthesizing TTX, a key multi-functionalized cyclitol was prepared from D-glucose employing the Ferrier(II) reaction. Stereospecific introduction of three functionalized branched chains were achieved via Peterson olefination and spiro α-chloroepoxidation of the corresponding carbonyl derivatives.
  • Choorikkat Ranjith, G. V. Srinivasan, K. K. Vijayan
    2010 Volume 83 Issue 3 Pages 288-290
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 26, 2010
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    Exploitation of a new boron-based catalyst, tributyl borate, for the formation of dihydropyrimidinones under solvent-free microwave-assisted conditions is described. The method is a simple, easy, fast, cost effective, and potentially green protocol for the formation of multi-functionalized pharmacologically active dihydropyrimidinones.
  • Keita Ikeue, Kyosuke Murakami, Satoshi Hinokuma, Kosuke Uemura, Dongji ...
    2010 Volume 83 Issue 3 Pages 291-297
    Published: March 15, 2010
    Released: March 15, 2010
    [Advance publication] Released: February 18, 2010
    JOURNALS RESTRICTED ACCESS
    The catalytic activity and thermostability of Rh catalysts (0.4% loading) have been studied using various metal phosphates (B, Al, Ga, Y, La, Pr, Zr, and Ce) as support materials. Temperature-programmed reactions of mixtures of NO, CO, C3H6, and O2 with the stoichiometric A/F ratio (14.6) exhibited a steep rise in conversion efficiency as a common feature of Rh supported on metal phosphates. The activity of Rh/AlPO4 was found to be the highest even after aging at 900 °C for 25 h in a stream of 10% H2O/air. Among four types of AlPO4 polymorphs having different BET surface area, i.e, berlinite (5 m2 g−1), cristobalite (1 m2 g−1), tridymite (82 m2 g−1), and microporous AlPO4-5 (330 m2 g−1), tridymite AlPO4 achieved the lowest light-off temperature. The slow grain growth of tridymite AlPO4 at ≤1000 °C is a possible reason for the stability against sintering, whereas one-dimensional micropores of AlPO4-5 are unstable in the high-temperature steam.
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