Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 88 , Issue 12
Showing 1-18 articles out of 18 articles from the selected issue
Award Accounts
The Chemical Society of Japan Award for Young Chemists for 2014
  • Shintaro Ida
    2015 Volume 88 Issue 12 Pages 1619-1628
    Published: December 15, 2015
    Released: December 15, 2015
    JOURNALS FREE ACCESS
    Nanosheets can be obtained by the exfoliation of layered compounds in a process where the three-dimensional structure of a bulk layered compound is converted into a two-dimensional structure. The change in the structural dimension is expected to result in new physical and/or chemical functions. This paper describes 1) light energy conversion properties, such as photocatalytic activity and emission for nanosheets obtained by exfoliation of the layered compounds, and 2) charge separation of photoexcited electrons and holes by the potential gradient formed in the ultrathin pn-junction prepared using nanosheets.
    This paper describes light energy conversion properties such as photocatalytic activity and emission for nanosheets, and charge separation of photoexcited electrons and holes by the potential gradient formed in the ultrathin pn-junction prepared using nanosheets. Fullsize Image
     
BCSJ Award Article
  • Shohei Yamashita, Yusaku Yamamoto, Misaki Katayama, Yasuhiro Inada
    2015 Volume 88 Issue 12 Pages 1629-1635
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 04, 2015
    JOURNALS FREE ACCESS
    The X-ray absorption fine structure (XAFS) spectroscopy was used to analyze the chemical state conversion of the Ni species in SiO2-supported Ni catalysts which were prepared by the impregnation method with various Ni loadings. The in situ XAFS measurements revealed that the calcined NiO species was quantitatively reduced by H2 to Ni(0) at around 580 K, and the formed Ni(0) species was reversibly and gradually oxidized by O2 up to 873 K. The transmission electron microscopy observation clarified that the Ni(0) particle size was dependent on the Ni loading. The dynamic observations using the time-resolved dispersive XAFS technique showed that the reduction process could be described by the first-order kinetics on the Ni species, which was different from the reduction kinetics of supported PdO species, which is a divalent metal oxide for the same family element. The different reduction kinetics is ascribed by the different atomic arrangement in the crystal structure between NiO and PdO.
    In situ XAFS measurements revealed the chemical state of SiO2-supported Ni species during the temperature-programmed reduction and oxidation. The kinetic investigation clarified the rate-determining oxygen migration after the fast surface reduction. Fullsize Image
     
 
  • Daeheum Cho, Yasuhiro Ikabata, Takeshi Yoshikawa, Jin Yong Lee, Hiromi ...
    2015 Volume 88 Issue 12 Pages 1636-1641
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 07, 2015
    JOURNALS RESTRICTED ACCESS
    The origin of the stability of diamondoid dimers containing very long carbon–carbon bonds was examined using density functional theory (DFT) calculations with local response dispersion correction. It has been suggested that noncovalent CH···HC contacts are the probable source of their extraordinary stability as evidenced by dispersion-corrected DFT calculations. In this work, we numerically proved that the small radical stabilization energy, which was achieved through the geometric relaxation of cleaved radicals, led to the high stability of diamondoid dimers compared to other hydrocarbons. The bond energy density analysis showed that the CH···HC contacts are repulsive though the dispersion force somewhat stabilizes the dimer. We further decomposed CH···HC interaction energies to discover strong attractive interaction between Cδ−···Hδ+ intermonomer contacts.
  • Takahide Yamaguchi, Junko Yano, Vittal K. Yachandra, Yuko Nihei, Hirom ...
    2015 Volume 88 Issue 12 Pages 1642-1652
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 04, 2015
    JOURNALS OPEN ACCESS
    The co-existence of “axial” and “rhombic” coordination environments has been demonstrated in a “Type 1” copper site of Pseudoazurin. This observation opens up previously not considered interpretations for the relationship between geometry and electronic structure of the four coordinate copper site. The Met16 variants of pseudoazurin were considered as model systems for investigating the effect of weak interactions from the second coordination sphere. The correlation between geometric and electronic structures of “Type 1” copper site was evaluated by the multi-edge (Cu K-edge and S K-edge) X-ray absorption spectroscopy (XAS) of Met16 variants of pseudoazurin. The co-existing axial and rhombic sites in pseudoazurin were characterized by Cu–ligand distances, effective nuclear charge, and Cu–S(Cys) covalency from XAS. The XAS results were correlated with DFT calculations for investigating the effect of protein environment from the inner-sphere and beyond around the Cu site. The combined experimental and theoretical results support the presence of a close correlation between outer sphere environment and inner sphere coordination environment. This is achieved in pseudoazurin by a previously undisclosed allosteric effect that involves a rearrangement of the protein tertiary structure.
  • Shinsaku Fujita
    2015 Volume 88 Issue 12 Pages 1653-1679
    Published: December 15, 2015
    Released: December 15, 2015
    JOURNALS RESTRICTED ACCESS
    For the purpose of characterizing cubane derivatives, the RS-stereoisomeric group and the corresponding stereoisograms are formulated by the extension of the point group Oh, where RS-permutations and ligand-reflections are defined on the basis of the rotations and reflections of Oh. According to the hierarchy concerning stereoisomers (i.e., pairs of enantiomers ⊆ quadruplets of RS-stereoisomers ⊆ multiplets of stereoisomers), respective enumerations under the point group Oh, under the RS-stereoisomeric group , and under the corresponding stereoisomeric group are conducted. The results of these enumerations are discussed by categorizing cubane derivatives into those with achiral proligands only and those with achiral and chiral proligands. The importance of the intermediate concept of RS-stereoisomers is emphasized by proposing a flowchart for classifying isomers and stereoisomers. C/A-Descriptors are proposed as a stereochemical notation for specifying global symmetries of cubane derivatives. The assignability of C/A-descriptors to type-I, type-III, and type-V stereoisograms is discussed in comparison with the unassignability of C/A-descriptors to type-II and type-IV stereoisograms. R/S-Descriptors are applied to the specification of local symmetries of cubane derivatives and compared with C/A-descriptors.
  • Maki Minakawa, Masataka Okubo, Motoi Kawatsura
    2015 Volume 88 Issue 12 Pages 1680-1682
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 04, 2015
    JOURNALS RESTRICTED ACCESS
    Direct N-alkylation of amines with alcohols in the presence of iron(III) phthalocyanine chloride as a catalyst in solvent-free conditions under microwave irradiation afforded the corresponding N-alkylamines in moderate to high yield with excellent selectivity.
  • Mehdi D. Esrafili, Nasibeh Saeidi, Mohammad Mehdi Baneshi
    2015 Volume 88 Issue 12 Pages 1683-1692
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 08, 2015
    JOURNALS RESTRICTED ACCESS
    In this work, ab initio calculations are performed to study chalcogen–chalcogen interactions in binary furan-YHX and thiophene-YHX (X = F, Cl, Br; Y = S, Se) complexes. Interaction energies of these complexes vary between −13.65 and −23.96 kJ mol−1 at MP2/aug-cc-pVTZ level. For a given X, complexes of SeHX have shorter chalcogen–chalcogen distances than SHX counterparts. The strength of the furan-YHX and thiophene-YHX complexes for a given Y decreases as follows: X = F > Cl > Br. Even though chalcogen–chalcogen interactions are mainly dominated by electrostatic effects, interaction energy decomposition analysis shows that polarization and dispersion effects also make important contributions to the stability of these complexes. In addition, charge-transfer from the O(S) lone pair to the σ*YX orbital leads to stabilization of these complexes. To further characterize the nature of chalcogen–chalcogen interactions, molecular electrostatic potential and quantum theory of atoms in molecules analyses are performed. Cooperative effects are observed when hydrogen bond and chalcogen–chalcogen interactions coexist in furan-YHF-HCN and thiophene-YHF-HCN.
  • Dariush Khalili, Ali Reza Banazadeh
    2015 Volume 88 Issue 12 Pages 1693-1706
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 10, 2015
    JOURNALS RESTRICTED ACCESS
    An efficient chemical method for the synthesis of benzimidazoles, benzothiazoles, and benzoxazoles has been developed through the condensation of various aldehydes with o-phenylenediamine, o-aminothiophenol, and o-aminophenol using graphene oxide (GO) as an oxidant in water. These benzazoles are also prepared through a one-pot oxidation/condensation tandem process by reacting alcohols with 2-amino(thio)phenol/aniline in the presence of GO in poly(ethylene glycol) as a safe media. Moreover, this carbonaceous material could be readily separated using a simple filtration.
  • Makoto Tadokoro, Takahiro Suda, Taishi Shouji, Kazuhiro Ohno, Kohei Ho ...
    2015 Volume 88 Issue 12 Pages 1707-1715
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 10, 2015
    JOURNALS OPEN ACCESS
    Synthetic molecular crystals with one-dimensional nanoporous channels containing H2O molecules act as model systems for pores such as aquaporin-1 in cell membranes. The structural characteristics of water molecular clusters (WMCs) were investigated using X-ray crystal analysis of {[NiII(cyclam)]3(TMA)2·35–34 H2O}n (2) (TMA: trimesate, cyclam: 1,4,8,11-tetraazacyclotetradecane) in a closed glass capillary to adjust the saturated humidity. The structural phase transition of WMCs with temperature depends only on the H2O structures around the centre, not on those in the primary hydrate layer nearest to the outer wall. The centre of a WMC was filled with H2O molecules under saturated humidity conditions; however, in air, the WMC had a nanotube-like structure with a vacant space. Thus, the centre portion of a WMC probably contains volatile and mobile H2O molecules. Therefore, we investigated the rapid proton conductivity using alternating current impedance and microwave spectroscopy and also carried out a transpiration experiment for transferring the mobile H2O molecules. The microwave spectroscopy results for 2 indicated no isotope effect, which would be observed by the rapid motion of H2O molecules without the breaking of hydrogen bonds between two site-disordering positions above the phase transition temperature. The results indicated reasonable water transpiration ability of the single crystal through its nanochannels; this property can be useful as a working principle to understand applications such as the desalination of seawater.
  • Kimika Matsuura, Hitoshi Watarai
    2015 Volume 88 Issue 12 Pages 1716-1718
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 10, 2015
    JOURNALS RESTRICTED ACCESS
    Chiral interaction between bilirubin (BR) and poly-L-lysine (PLL) was investigated by a centrifugal liquid membrane-circular dichroism method. The interfacial self-aggregation of BR in pH 6 and the preferential interaction between the P form of BR and α-helix form of PLL at the interface under pH 10–12 were observed.
  • Frederic Delbecq, Itsuki Yamano, Takeshi Kawai
    2015 Volume 88 Issue 12 Pages 1719-1725
    Published: December 15, 2015
    Released: December 15, 2015
    JOURNALS RESTRICTED ACCESS
    The synthesis of a long alkylaminoamide dicarboxylic acid amphoteric species has been achieved. Employed as capping agent, the reduction of ionic silver in water led to the formation of small (10–100 nm) and hydrophobic diacid bilayer coated silver nanoparticles (AgNPs). In a biphasic system (e.g. H2O–CHCl3), a pH-controlled and reversible phase transfer phenomenon was observed. At different stages, the formation of these nanoparticles was studied by UV–vis spectroscopy, their stability was controlled by zeta-potential measurement and both shape and morphology were observed by transmission electron microscopy (TEM). The ionic strength of the AgNPs was tested by the addition of inorganic salt electrolyte (NaCl, CaCl2). A NaCl concentration dependant size fractionation of the AgNPs between the same above biphasic system was also studied by means of analytical techniques such as dynamic light scattering (DLS), TEM, and UV–vis spectroscopy.
  • Shinji Tanaka, Yusuke Suzuki, Masaharu Matsushita, Masato Kitamura
    2015 Volume 88 Issue 12 Pages 1726-1734
    Published: December 15, 2015
    Released: December 15, 2015
    JOURNALS RESTRICTED ACCESS
    An axially chiral naphthyl-substituted picolinic acid (R-Naph-PyCOOH) or its allyl ester (R-Naph-PyCOOAll) acts as an excellent ligand for catalytic asymmetric dehydrative intramolecular allylation. Towards the future development of a high performance catalysis using R-Naph-PyCOOH or its carba-analogue (R-Naph-PhCOOH), the stereochemical stability of R-Naph-PyCOOAll and R-Naph-PhCOOAll has been investigated by a systematic change in the ortho-substituent R on the naphthalene ring from CH3 to C6H5 and CH3O to provide a range of effective radius (ER) and Hammett standard σ constant (σp). Enantiomerically pure R-Naph-PyCOOAll and R-Naph-PhCOOAll were prepared, and the rotational energy barriers ΔG(sp2N) and ΔG(sp2CH) as well as the racemization half-life (t1/2) were determined by time-interval chiral HPLC analysis of the enantiomer ratio (er). These experiments revealed have been i) that replacement of sp2CH with sp2N lowers ΔG at least by 14 kJ mol−1 (3.3 kcal mol−1), and ii) that the degree of the ΔG lowering (ΔΔG) is not proportional to ER, but has a high linear correlation to σp with a negative ρ value. In this particular system, a synergistic effect of the steric and electronic factors stabilizes TSφ180 with a 180° dihedral angle of CH3OC(2′)=C(1′)–C(6)=N(1) over TSφ0, decreasing the t1/2 of CH3O-Naph-PyCOOAll to 7 days from 1600 years of CH3-Naph-PyCOOAll.
  • Satoru Hirakawa, Yuka Kotani, Tomoyuki Hayasaki, Hisashi Honda
    2015 Volume 88 Issue 12 Pages 1735-1745
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 17, 2015
    JOURNALS RESTRICTED ACCESS
    Spherical-type cations of 1-alkyl-4-aza-1-azoniabicyclo[2,2,2]octane (N-R DABCO, R = Me, Et) form ionic plastic crystals with BEt3Me and BEt4. Differential scanning calorimetry (DSC) analysis of [N-R DABCO][BEt3Me] and [N-R DABCO][BEt4] shows entropy changes of 49–73 J K−1 mol−1 at transition temperatures for the highest-temperature solid phase. X-ray diffraction (XRD) spectra show these salts form CsCl-type cubic structures. 1H and 13C nuclear magnetic resonance (NMR) shows that the cation and anion undergo isotropic reorientation in the highest-temperature solid phase. NMR spin-lattice relaxation times (T1) reveal that activation energies for this motion are smaller than reported for [NEtxMe(4−x)][BEt3Me] (x = 0–4), in contrast, electrical conductivity measurements show activation energies of ion transfer for these salts are similar to those of [NEtxMe(4−x)][BEt3Me]. In contrast to [N-R DABCO][BEt3Me, BEt4] salts, [N-R DABCO][BBu4] (R = Me, Et, Pr, Bu) show large entropy changes at their melting points. Complex XRD powder patterns and broad NMR spectra were also obtained. Based on these results, it can be concluded that the [N-R DABCO][BBu4] compounds show no plasticity under ambient conditions.
  • Koichiro Takao, Kohei Arakawa, Takahiro Mori, Masayuki Harada, Yasuhis ...
    2015 Volume 88 Issue 12 Pages 1746-1751
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 14, 2015
    JOURNALS RESTRICTED ACCESS
    Extraction behavior of U(VI) from an HNO3 aqueous solution to 1-butyl-3-methylimidazolium nonafluorobutanesulfonate ([BMI][NfO]) ionic liquid and recovery of the extracted U(VI) by using H2O2 were investigated. With increasing [HNO3], the distribution ratio of U(VI) tends to decrease (e.g., 4.08 at [HNO3] = 0.01 M, 0.15 at [HNO3] = 1.00 M). Such extraction behavior is mainly governed by [H+], while coordination of NO3 to UO22+ also offers minor contribution to prevent partitioning of U(VI) to [BMI][NfO]. The U(VI) extraction in the current system is exclusively driven by NfO to form an outer-sphere complex like {[UO2(OH2)5](NfO)4}2−. Addition of 30 wt % H2O2 to [BMI][NfO] containing U(VI) resulted in pale yellow precipitate of [(UO2)(O2)(H2O)2]·2H2O. The recovery efficiency increases with increasing pH of the aqueous layer, and reaches >90% at pH >1.5. This is in line with deprotonation from H2O2 through the precipitation of [(UO2)(O2)(H2O)2]·2H2O, i.e., UO22+ + H2O2 + 4H2O = [(UO2)(O2)(H2O)2]·2H2O (s) + 2H+.
  • Koji Nemoto, Ken-ichi Tominaga, Kazuhiko Sato
    2015 Volume 88 Issue 12 Pages 1752-1754
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 17, 2015
    JOURNALS RESTRICTED ACCESS
    Combination use of AlCl3·6H2O with H3PO4 has led to the development of an efficient water-tolerant catalyst system, acting cooperatively in aqueous media to produce levulinic acid from microcrystalline cellulose. This catalyst system was extended to the direct transformation of various raw biomass resources to levulinic acid in good yields.
  • Masaki Matsubara, Tetsu Yonezawa, Hiroki Tsukamoto
    2015 Volume 88 Issue 12 Pages 1755-1759
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 17, 2015
    JOURNALS RESTRICTED ACCESS
    It has been found in this study that the glass transition temperatures can be considered as the lowest temperature for sintering metal fine particles to obtain electro-conductive metallic layers from the differential scanning calorimetry measurement of the fine particles. Gelatin-stabilized copper fine particles could be sintered to form an electrically conductive copper layer with a resistivity of 1.9 × 10−5 Ω cm at as low as 150 °C using oxidation–reduction two-step sintering.
  • Tsunehisa Hirashita, Masaki Ogawa, Reina Hattori, Sota Okochi, Shuki A ...
    2015 Volume 88 Issue 12 Pages 1760-1764
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 25, 2015
    JOURNALS RESTRICTED ACCESS
    A series of 3,3′-diindolylmethanes were prepared in high yields from indoles and aldehydes under subcritical water conditions without the addition of catalysts. 3-Alkenylindoles were also obtained in good yields from aldehydes bearing benzylic hydrogen atoms.
  • Yoshiyuki Kuroda, Kazuya Yamaguchi, Kazuyuki Kuroda, Noritaka Mizuno
    2015 Volume 88 Issue 12 Pages 1765-1772
    Published: December 15, 2015
    Released: December 15, 2015
    [Advance publication] Released: September 30, 2015
    JOURNALS RESTRICTED ACCESS
    Layered double hydroxides (LDHs) are anion-exchanging materials applicable to removal of harmful anionic species from water. Here, we report novel highly dispersible LDH nanoparticles (LDHNPs) which can remove methylorange (MO), a model anionic pollutant, quite rapidly. The LDHNPs are prepared by using tris(hydroxymethyl)aminomethane. The LDHNPs aggregate into sheet-like structure by face-to-face association or house-of-cards structure by edge-to-face association. The removal of MO by the LDHNPs with the house-of-cards structure reaches 95% of equilibrium level within only 5 s, which is much faster than the sheet-like aggregates and conventional large LDHs by at least two orders of magnitude. Therefore, it is found that the structural control of aggregates is critical to the dispersibility of LDHNPs and the ultrafast removal of anionic dye.
feedback
Top