Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 89 , Issue 9
Showing 1-16 articles out of 16 articles from the selected issue
Award Accounts
The Chemical Society of Japan Award for Creative Work for 2014
  • Takehiko Mori
    2016 Volume 89 Issue 9 Pages 973-986
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: May 12, 2016
    JOURNALS RESTRICTED ACCESS

    Energy bands of organic conductors are calculated on the basis of the estimation of intermolecular overlap integrals and the tight-binding approximation. The resulting Fermi surface has been investigated by the measurements of low-temperature magnetoresistance in detail. However, we have to take electron correlation into account to explain the variation of the metal-insulator transition temperatures and the universal phase diagram. In particular, intermolecular Coulomb repulsion gives a variety of charge-order patterns, in which non-stripe charge order is important in a triangular network of organic conductors. Non-stripe charge order is an origin of flat resistivity, nonlinear conductivity, and potentially Dirac fermions. The estimation of intermolecular interaction is extended to the πd-systems, where the magnetic interactions J between the π-electrons and metal spins make a network. To discuss the charge transport in organic transistors, energy levels of the molecules are important. However, since the energy levels are considerably modified at the metal/organic interface, it is useful to use chemical doping and organic charge-transfer salts in the conducting parts of organic transistors. Temperature dependence of an organic transistor comes from the midgap trap states, but eliminating the traps in a single-crystal transistor, we can achieve band-like transport maintained down to low temperatures.

    Energy band calculation of organic conductors is extended by considering electron correlation to explain the systematic variation of the metal-insulator transitions, πd-interactions, charge order, nonlinear conductivity, and Dirac fermions. Similar analysis is applied to organic transistors. Fullsize Image
     
Accounts
  • Shinsaku Fujita
    2016 Volume 89 Issue 9 Pages 987-1017
    Published: September 15, 2016
    Released: February 17, 2017
    JOURNALS RESTRICTED ACCESS

    Chirality under point-group symmetry and RS-stereogenicity under RS-permutation-group symmetry are discussed from a viewpoint of two kinds of handedness, which are proposed on the basis of whether or not ligand reflections are taken into consideration. After the additional formulation of sclerality under ligand-reflection-group symmetry, the three groups are integrated to generate RS-stereoisomeric groups, which are represented by stereoisograms as diagrammatic expressions. The vertical direction of a stereoisogram is concerned with (self-)enantiomeric relationships or chirality/achirality for supporting Le Bel’s way, while the horizontal direction is concerned with (self-)RS-diastereomeric relationships or RS-stereogenicity/RS-astereogenicity for supporting van’t Hoff’s way. By taking account of the diagonal direction for characterizing (self-)holantimeric relationships or sclerality/asclerality, the two kinds of handedness (chirality and RS-stereogenicity) are integrated to develop the concept of RS-stereoisomerism, which is an intermediate concept for mediating between enantiomerism and stereoisomerism. The creation of RS-stereoisomerism as an intermediate concept means the Aufheben of van’t Hoff’s way and Le Bel’s way. Thereby, Fujita’s stereoisogram approach has brought about a paradigm shift, so that modern stereochemistry has been restructured substantially on the basis of mathematical formulations, where true remedies for the misleading terminology of modern stereochemistry have been developed in a rational fashion. In particular, the hierarchy of isomers and stereoisomers has been thoroughly revised by adding RS-stereoisomerism, so as to develop a new flowchart based on equivalence relationships and equivalence classes, as exemplified by using various skeletons as probes.

    Fujita’s stereoisogram approach integrates two kinds of handedness, i.e., chirality and RS-stereogenicity. Thereby, it brings about the Aufheben of van’t Hoff’s way and Le Bel’s way, so that it provides us with a rational flowchart for classifying isomers and stereoisomers. Fullsize Image
     
 
  • Naoya Sagawa, Shunzo Takabatake, Toshiyuki Shikata
    2016 Volume 89 Issue 9 Pages 1018-1025
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: May 27, 2016
    JOURNALS RESTRICTED ACCESS

    The formation of anti-parallel dimers ((EC)2) of ethylene carbonate (EC) in solution is discussed via dielectric data determined over a frequency range up to 3 THz. Two major dielectric processes have been identified in both benzene (Bz) and dimethyl carbonate (DMC) solutions. The relaxation times were ca. 8 and ca. 20 ps in Bz, and ca. 20 and ca. 40 ps in DMC solution for the two relaxation processes, respectively. The population of monomeric EC was evaluated from the strength of the faster relaxation mode assigned to the rotational mode of monomeric EC. Equilibrium constants (Kd) for the (EC)2 formation in the two solvents were determined as functions of the concentration at room temperature assuming a process, 2EC ⇌ (EC)2. The libration of EC molecules was observed as a sharper resonance signal at ca. 1.5 × 1013 s−1 when they existed as monomeric EC rather than in the form of (EC)2 in Bz, whereas the signal was not so sharp in DMC. The fact that the determined Kd values depended on the solvent: 3–7 M−1 in Bz and 0.05–0.1 M−1 in DMC, reveals that the choice of solvent governs the efficiency of (EC)2 formation. The Kd showed reasonable agreement with the previously determined equilibrium constants using Raman scattering techniques.

  • Yoshiaki Hirano, Yuka Kasai, Kunimasa Sagata, Yuichi Kita
    2016 Volume 89 Issue 9 Pages 1026-1033
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 08, 2016
    JOURNALS RESTRICTED ACCESS

    In the utilization of biomass for fuels and chemicals, the key reactions involved are hydrogenolysis and deoxygenation using hydrogen. Unfortunately, the industrial use of molecular hydrogen is limited because of various drawbacks, such as high cost and considerable hazards associated with high-pressure operation. In this study, a unique chemical manufacturing process was proposed for inducing the hydrogenolysis and deoxygenation of biomass carbohydrates using hydrogen generated in situ from the reaction between metallic iron and water. From the results obtained, hydrogen generated in situ by metallic iron particles (hydrogen-generating agent) combined with a carbon-supported palladium catalyst (hydrogenation catalyst) transforms glucose to C3 platform chemicals, such as propylene glycol, hydroxyacetone, and lactic acid. Moreover, reaction conditions and mechanism were also evaluated. With the use of the proposed system, value-added chemicals were produced from biomass carbohydrates by using renewable sources of energy (such as hydrogen generated from the reaction between iron and water) without the complete dependence on fossil resources.

  • Minh Anh Truong, Koji Nakano
    2016 Volume 89 Issue 9 Pages 1034-1040
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: May 30, 2016
    JOURNALS RESTRICTED ACCESS

    Two kinds of ladder-type thiophene-fused π-conjugated compounds, benzo[2,1-b:3,4-b′]bis[1]benzothiophene (syn-BBBT) and dinaphtho[2,3-d:2′,3′-d′]benzo[2,1-b:3,4-b′]dithio-phene (syn-DNBDT), were successfully synthesized. Photophysical and electrochemical properties were evaluated by UV–vis and photoluminescence spectroscopies and cyclic voltammetry as well as theoretical calculations. These properties were compared with those of structural isomers and oxygen analogs to reveal the effect of the fused position of thiophene rings and the fused heteroaromatic rings on π-conjugation. Field-effect transistors with the thin films of syn-BBBT and syn-DNBDT demonstrated typical p-type semiconductor characteristics with relatively high mobilities of <1.3 × 10−1 cm2 V−1 s−1.

  • Keishiro Tahara, Shogo Akehi, Tomoya Kadowaki, Jun-ichi Kikuchi
    2016 Volume 89 Issue 9 Pages 1041-1047
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 02, 2016
    JOURNALS RESTRICTED ACCESS

    A new Pd complex Pd(tBu2bpy)(FcC) 2Fc (FcC = 4-ferrocenylcatecholato, tBu2bpy = 4,4′-di-tert-butyl-2,2′-dipyridyl) was synthesized and characterized using 1H and 13C NMR spectroscopy, and ESI-MS. Electrochemical analysis of 2Fc using cyclic voltammetry in CH2Cl2/nBu4NPF6 revealed two well-defined, quasi-reversible waves assigned to the sequential oxidation of the Pd(tBu2bpy)(C) and ferrocene (Fc) moieties. The potential splitting between the waves (519 mV) indicated that there was an electronic interaction between both moieties. The one-electron-oxidized species of 2Fc was investigated using DFT calculations and UV–vis–NIR spectroscopy, and its charge-transfer property was compared with that of Pt(tBu2bpy)(FcC) 1Fc, FcV (4-ferrocenylveratrole), and FcA (4-ferrocenylcatechol bis(acetate)). 2Fc+ was Fc+-centered, rather than semiquinone-ligand centered, and exhibited an ICT transition band from to the catecholate to the Fc+ moiety in the NIR region. The electronic coupling (HAB) value of 2Fc+ (790 cm−1) was placed between FcV+ (660 cm−1) and 1Fc+ (1050 cm−1). Electronic interactions between the organometallic center and the non-innocent moiety were modulated by substitution of the metal ion (M2+ = Pt2+, Pd2+) in this series.

  • Yasutomo Tanihara, Ai Nozaki, Yasutaka Kuwahara, Kohsuke Mori, Hiromi ...
    2016 Volume 89 Issue 9 Pages 1048-1053
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 13, 2016
    JOURNALS RESTRICTED ACCESS

    An alternative approach to fabricate thin layers of metal organic frameworks (MOFs) on metal substrates without any needs of specific apparatuses was developed. Cu substrates were immersed into acid solution containing 1,3,5-benzenetricarboxylic acid (H3BTC) organic linker for the MOFs synthesis, where in-situ dissolved Cu2+ ions were assembled to form [Cu3(BTC)2] (HKUST-1; BTC: 1,3,5-benzenetricarboxylate) crystals on the Cu substrates. The optimization of the choice of acids, solvents and preparation conditions were carried out to fabricate densely packed MOFs thin layers on Cu substrates. Use of a low-polarity solvent, benzyl alcohol (ε = 13), afforded a best balance between a dissolution rate of Cu and a coordination rate of the ligands, which led to the formation of a homogeneous thin layer composed of densely deposited small HKUST-1 crystals with a thickness of up to ca. 5 µm on the Cu substrates. The thus synthesized MOFs thin layers exhibited a gas-adsorption property for H2 and CO2 with an excellent mechanical stability, making this method a promising approach to functionalize metal substrates.

  • Ikumi Akita, Yohei Ishida, Tetsu Yonezawa
    2016 Volume 89 Issue 9 Pages 1054-1056
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 14, 2016
    JOURNALS RESTRICTED ACCESS

    Sputtering deposition of gold over a liquid matrix containing different ligands with thiolate, amine, or carboxy groups resulted in the formation of spherical gold nanoparticles (Au NPs) in the range of 2.1 to 6.7 nm, and the diameters gradually decreased as the affinity of the ligands for Au increases.

  • Makoto Ishidoshiro, Hiroaki Imoto, Kensuke Naka
    2016 Volume 89 Issue 9 Pages 1057-1062
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 16, 2016
    JOURNALS RESTRICTED ACCESS

    A metal-organic framework (MOF) was constructed based on a 1,4-dihydro-1,4-diarsinine (DHDA) tetracarboxylic acid ligand, which was newly synthesized via hydrolysis of DHDA tetramethyl tetracarboxylate. The lone pairs of the arsenic atoms were not involved in the construction of the MOF. Notably, the preparation procedure of the MOF was performed under ambient atmosphere without any protecting groups, while inert atmosphere is required for incorporating trivalent phosphorus atoms.

  • Kazuhiro Nakabayashi, Yuhei Takeuchi, Hideharu Mori
    2016 Volume 89 Issue 9 Pages 1063-1068
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 15, 2016
    JOURNALS RESTRICTED ACCESS

    We developed a series of perylene bisimide (PBI)-based small molecules with donor–acceptor (D–A) architecture (PBI1, PBI2, and PBI3). By tuning the D–A architecture, intramolecular charge transfer (ICT) could be controlled; as a result, optical band gaps and HOMO levels of PBI13 were widely tunable from 1.83 to 1.44 eV and from −5.85 to −5.55 eV, respectively. Furthermore, extremely wide light absorption over 900 nm was observed in the thermal annealed PBI13 blend film. The grazing incidence wide angle X-ray scattering (GIWAXS) analysis demonstrated that the as-spun PBI2 thin film had the highest ordered nanostructure among PBI13, in which diffraction corresponding to π–π stacking was clearly observed in isotropic orientations.

  • Hirotaka Endo, Yuji Suzaki, Motonori Komura, Kohtaro Osakada
    2016 Volume 89 Issue 9 Pages 1069-1071
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 08, 2016
    JOURNALS RESTRICTED ACCESS

    Alternating transition metal-organic bi- and multilayers composed of dicationic (ethylenediamine)palladium(II) and platinum(II) complexes and N-alkyl-4,4′-bipyridinium, [(η3–C3H5)Pd{4,4′-bpy-N-(CH2)12OC6H3-3,5-(OMe)2}(OAc)]NO3 and [M{4,4′-bpy-N-(CH2)12OC6H3-3,5-(OMe)2}2(en)](NO3)4 (M = Pd, Pt, en = 1,2-ethylenediamine), were synthesized on mica surface by simple casting method from aqueous solution.

  • Kunihiro Ichimura
    2016 Volume 89 Issue 9 Pages 1072-1080
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 21, 2016
    JOURNALS RESTRICTED ACCESS

    E-to-Z photoisomerization of 4-dimethylaminoazo-benzene (DMAz) in solution and in aqueous dispersion of fine crystals was analyzed by means of higher-order derivatives. UV-induced changes in derivative spectra of DMAz in hexane led to the identification of vibration level transitions (VLTs) of both E- and Z-isomers and to the estimation of conversions of photoisomerization by tracing extrema of VLT sub-peaks of E-isomer. An aqueous dispersion of DMAz crystals prepared by bead-milling exhibits an extraordinarily broad n,π*-band, which is quite different from that in solution. The irradiation of the dispersion with 365 nm light resulted in the decrement of the absorption band due to the solid-state photoisomerization. The corresponding eighth-derivatives showed the distinctive decline of VLT bands assignable to E-isomer to confirm the photoisomerization. The UV-induced decrement of VLT bands was followed by plotting extremum values of the eighth-order derivatives as a function of exposure time. It was proposed that the solid-state photoisomerization of DMAz is comprised of the fast process at the surface layers and the subsequent slow one in the bulk, taking the observation into account that the melting depression of melting transition occurs by the nanodownsizing of the crystals.

  • Kazuki Fujii, Koichi Mitsudo, Hiroki Mandai, Seiji Suga
    2016 Volume 89 Issue 9 Pages 1081-1092
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: May 30, 2016
    JOURNALS RESTRICTED ACCESS

    We developed an acylative kinetic resolution of secondary carbinols using a binaphthyl-based N,N-4-dimethylaminopyridine (DMAP) derivative 1d with tert-alcohol substituents. The reaction proceeded with a wide range of carbinols with moderate to high selectivity (s) (up to s = 79.5). Kinetic studies revealed that catalyst 1d was more catalytically active than the corresponding bis-methyl ether 1d′ or DMAP. Hydrogen bonding between tert-alcohols of the catalyst and secondary carbinols was responsible for the enhanced reaction rate and high enantioselectivity.

BCSJ Award Article
  • Karakkadparambil Sankaran Sandhya, Nobuaki Koga, Masataka Nagaoka
    2016 Volume 89 Issue 9 Pages 1093-1105
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 01, 2016
    JOURNALS RESTRICTED ACCESS

    The [SiH2(Ind)2ZrCH3]+ (Ind = indenyl) catalyzed stereoregularity of propylene polymerization mechanism has been investigated at M06 level of theory. Four different approaches of propylene to the reactive catalyst lead to four isomeric products due to the C2 symmetry of bridged Ind ligand of the catalyst. Consequently, various possibilities of propylene attack as well as orientation of polymer chain yield numerous stereoisomers. The calculations of the first and second insertions with various conformers clarified the most favorable reaction pathway and showed that isotactic propagation is more favorable (3.5 kcal mol−1) than syndiotactic propagation. The structures of resting state catalysts displayed various agostic interactions of the CH bond with the Zr center which stabilize the catalytic systems and play important roles in determining the favorable reaction pathway. The influence of counter anion [CH3B(C6F5)3] on the reactivity of the catalyst was also studied. The results also confirm that the trans orientation of the counter anion with respect to propylene is more favorable than its cis orientation and clarify the most favorable reaction pathway in the first and second insertion. Because agostic interactions are involved in various aspects, AIM analysis has been used to find the bonding nature of agostic interactions as well as ion-pair bonds. The overall results suggest that rigidity of ansa-zirconocene, unique structure of C2 symmetric ansa ligand, influence of [CH3B(C6F5)3] and β agostic interaction may restrict the attack of propylene only to isotactic polymerization and not to syndiotactic polymerization.

    All possible pathways of first and second insertion of propylene in [SiH2(Ind)2ZrCH3]+[CH3B(C6F5)3] provide a new insight into the effect of counter anion in the polymerization reaction mechanism. Fullsize Image
     
 
  • Hideaki Shirota, Shohei Kakinuma, Kotaro Takahashi, Akito Tago, Hocheo ...
    2016 Volume 89 Issue 9 Pages 1106-1128
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 13, 2016
    JOURNALS RESTRICTED ACCESS

    We studied the ultrafast dynamics of 40 aromatic cation based ionic liquids (ILs) by means of femtosecond Raman-induced Kerr effect spectroscopy. The low-frequency Kerr spectra (ca. 0.3–700 cm−1) of the ILs were obtained from the Kerr transients by Fourier-transform deconvolution analysis. The low-frequency Kerr spectra in the frequency range less than 200 cm−1 coming mainly from the intermolecular vibrations for the ILs were discussed in terms of (i) anion dependence, (ii) imidazolium cations vs. pyridinium cations, (iii) alkyl group dependence, and (iv) effect of methylation in aromatic cations. Several liquid properties, such as density, viscosity, electrical conductivity, and surface tension, of the present sample ILs at 293 K were also estimated in this study. We clarified that the aromatic cation based ILs show a different relation of the first moment of the low-frequency spectral band to the bulk liquid parameter, which is the square root of surface tension divided by liquid density, from aprotic molecular liquids. The slope of the first moment to the bulk parameter for the aromatic cation based ILs is gentler than that for aprotic molecular liquids.

  • Akiyuki Harada, Sayako Koge, Joji Ohshita, Yoshiro Kaneko
    2016 Volume 89 Issue 9 Pages 1129-1135
    Published: September 15, 2016
    Released: February 17, 2017
    [Advance publication] Released: June 20, 2016
    JOURNALS RESTRICTED ACCESS

    A thermally stable room temperature ionic liquid containing cage-like oligosilsesquioxane (POSS) with two types of side-chain groups (Amim-Cage-SQ-IL) was successfully prepared by the hydrolytic condensation of a mixture of two organotrialkoxysilanes from which one contained a quaternary ammonium group trimethyl[3-(triethoxysilyl)propyl]ammonium chloride (TTACl) and the other an imidazolium group 1-methyl-3-[3-(triethoxysilyl)propyl]imidazolium chloride (MTICl). Moreover, superacid bis(trifluoromethanesulfonyl)imide (HNTf2) was used as a catalyst in water/methanol mixed solvent. Amim-Cage-SQ-IL exhibited a glass-transition temperature (Tg) of −8 °C as indicated by a baseline shift in the differential scanning calorimetry (DSC) curve. In addition, fluidity was visually observed at ca. 30 °C, i.e., Amim-Cage-SQ-IL is a room temperature ionic liquid. Because of the low molecular symmetry of the resulting POSS compound containing two different randomly distributed side-chain groups, its crystallization was suppressed, leading to the disappearance of the melting temperature (Tm). Consequently, Amim-Cage-SQ-IL exhibited low flow temperature. Moreover, the pyrolysis temperatures of Amim-Cage-SQ-IL were extremely high (its pyrolysis temperature of the 5% weight loss was 420 °C).

feedback
Top