Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 82 , Issue 7
Showing 1-17 articles out of 17 articles from the selected issue
Award Accounts
The Chemical Society of Japan Award for Creative Work for 2007
  • Masahiko Takahashi
    2009 Volume 82 Issue 7 Pages 751-777
    Published: July 15, 2009
    Released: July 10, 2009
    JOURNALS FREE ACCESS
    Over the last four decades an experimental method has been developed for looking at electron orbitals in momentum space. The method, called electron momentum spectroscopy (EMS), is based on the electron-impact ionizing reaction near the Bethe ridge at incident electron energies of the order of 1 keV or higher. This account reviews frontiers of the field, involving the first approach to molecular frame EMS that enables one to look at molecular orbitals in three-dimensional form.
    A triple coincidence spectrometer has been developed, which can visualize molecular orbital patterns in three-dimensional form through measurements of vector correlations between the two outgoing electrons and the fragment ion produced in electron Compton scattering. Fullsize Image
The Chemical Society of Japan Award for Young Chemists for 2008
  • Hideki Yorimitsu, Koichiro Oshima
    2009 Volume 82 Issue 7 Pages 778-792
    Published: July 15, 2009
    Released: July 10, 2009
    JOURNALS FREE ACCESS
    Metal-mediated or -catalyzed retro-allylation of homoallyl alcohol that proceeds via a six-membered transition state has appeared as a new useful method to prepare allylmetals. A crotylzirconium reagent undergoes stereoselective allylation of aromatic aldehyde at −78 and 25 °C to provide threo- and erythro-homoallyl alcohols, respectively. Although the threo isomer is formed as usual via a six-membered chair transition state under kinetic control, the erythro selectivity is rationalized by considering isomerization of the threo adduct through a retro-allylation process. The retro-allylation of a bulky gallium homoallyloxide occurs to generate (Z)- and (E)-crotylgallium reagents stereospecifically, starting from erythro- and threo-homoallyl alcohols, respectively. The (Z)- and (E)-crotylgallium reagents react with aromatic aldehydes in situ to afford the corresponding erythro- and threo-homoallyl alcohols, respectively. Treatment of rationally designed tertiary homoallyl alcohols with aryl halides under palladium catalysis yielded the corresponding allylarenes stereo- and regioselectively, by replacing the conventional transmetalation step in the cross-coupling reaction with alkoxide–halide exchange followed by a retro-allylation reaction. The retro-allylation reaction is also applicable to nickel and rhodium at this stage, and may to any other metals in principle. Reversible additions of pentamethylcyclopentadienyl anion to carbonyl compounds are also described.
    Metal-mediated or -catalyzed retro-allylation of homoallyl alcohol that proceeds via a six-membered transition state has emerged as a new useful method to prepare allylmetals. Fullsize Image
BCSJ Award Article
  • Akihiro Yuasa, Takahiro Sasamori, Yoshinobu Hosoi, Yukio Furukawa, Nor ...
    2009 Volume 82 Issue 7 Pages 793-805
    Published: July 15, 2009
    Released: July 10, 2009
    JOURNALS FREE ACCESS
    Stable 1,2-bis(metallocenyl)disilenes were synthesized for the first time and were characterized by spectroscopic and X-ray crystallographic analyses. On the basis of cyclic voltammograms, (E)-1,2-bis(ferrocenyl)-1,2-bis(2,4,6-triisopropylphenyl)disilene (1a) was found to be a stable five-electron redox system with four steps, while (E)-1,2-bis(ruthenocenyl)-1,2-bis(2,4,6-triisopropylphenyl)disilene (1b) showed four-step redox couples with four electrons. The UV–vis spectra and theoretical calculations for these disilenes suggested that they should be novel d–π conjugated systems containing a disilene unit. In addition, chalcogenation reactions of 1a resulted in the formation of new heterocyclic compounds bearing ferrocenyl units. For example, the first stable 1,2,3,4-dithiadisiletane derivative was obtained by the sulfurization reaction of 1a.
    Stable 1,2-bis(metallocenyl)disilenes were synthesized for the first time and characterized by spectroscopic and X-ray crystallographic analyses. They are novel d–π conjugated systems containing a disilene unit. Fullsize Image
  • Keiko Nishikawa, Shaolan Wang, Takatsugu Endo, Ken-ichi Tozaki
    2009 Volume 82 Issue 7 Pages 806-812
    Published: July 15, 2009
    Released: July 10, 2009
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    We studied the melting and crystallization behaviors of 1-isopropyl-3-methylimidazolium bromide ([i-C3mim]Br) using a laboratory-made differential scanning calorimeter (DSC) with nanowatt stability and sensitivity. In addition to common behaviors for many ionic liquids such as premelting over a wide temperature range and excessive supercooling, we observed unique thermal phenomena: reversible phase transitions of domains in the premelting region, rhythmic crystallization and melting, and intermittent crystallization. The latter two phenomena were observed in the returning experiments from the premelting region at a cooling rate as slow as 0.05 mK s−1. It is considered that these phenomena occurred because an [i-C3mim]+ ion is capable of taking plural stable conformations and the conformational changes occurred linking with melting and crystallization. We interpret these curious phenomena as the phase changes of the locally melted domains composed of different conformers, which significantly hindered the overall phase changes.
  • K. K. Upadhyay, Ajit Kumar, Rakesh K. Mishra, Rajendra Prasad
    2009 Volume 82 Issue 7 Pages 813-815
    Published: July 15, 2009
    Released: July 10, 2009
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    We report hereby use of p-nitrophenyltriazenopurine, (PNTP) as a colorimetric receptor for recognition of d10 metal ions in DMSO through visible color changes. All the chosen metal ions showed 1:1 stoichiometry with PNTP. Among the chosen metal ions HgII was most preferred by PNTP.
  • Ryuta Ishikawa, Hitoshi Miyasaka, Masahiro Yamashita
    2009 Volume 82 Issue 7 Pages 816-818
    Published: July 15, 2009
    Released: July 10, 2009
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    The use of a low-spin FeIII complex bearing three imidazolate groups in a reaction with MnIII salen-type complexes provided two different imidazolate-bridged MnIII–FeIII assemblies, a dinuclear complex and a one-dimensional chain, dependent on the salen ligand and counter ion used. Both compounds exhibit a ferromagnetic exchange between MnIII and FeIII centers via the imidazolate linkage.
  • Yosuke Uchiyama, Jun Sugimoto, Munenori Shibata, Gaku Yamamoto, Yasuhi ...
    2009 Volume 82 Issue 7 Pages 819-828
    Published: July 15, 2009
    Released: July 10, 2009
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    2,3,6,7,14,15-Hexamethyl-9,10-diphosphatriptycene (1), 2,3,6,7,14,15-hexamethyl-9-phospha-10-stibatriptycene (2), and 2,3,6,7,14,15-hexamethyl-9,10-distibatriptycene (3) were synthesized and their molecular structures were determined by X-ray crystallography. Reactions of 2 and 3 with bromine gave the corresponding adducts 8 and 9 with the compositions 2·2Br2 and 3·2Br2, respectively. Both of the adducts 8 and 9 have a zwitterionic structure composed of a hexacoordinate stiborate anion, (R3SbBr3) and a tetracoordinate phosphonium/stibonium cation (R3MBr+: M = P or Sb) in the crystalline state. 1H and 31P NMR spectra of the adduct 8 indicated that the structure is static in solution at room temperature. On the other hand, 1H NMR spectra of the adduct 9 suggested fast topomerization at 27 °C, which becomes slow on the NMR time scale at −90 °C. Recrystallization of the adduct 9 from THF–mesitylene gave crystals with the composition of 3·2Br2·2THF, in which each antimony atom bonds to two bromine atoms and one THF oxygen to give an octahedral geometry.
  • Vincent Gembus, Nathalie Sala-Jung, Daniel Uguen
    2009 Volume 82 Issue 7 Pages 829-842
    Published: July 15, 2009
    Released: July 10, 2009
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    Refluxing trimethylhydroquinone 2 in 10:1 dodecane/CH2Cl2 with linalool 3b (two-fold excess) and camphorsulfonic acid, then treating the crude condensation product (consisting of a mixture of the chromanols 1b and 1c, alongside the tricyclic compounds 9 and 10) sequentially with Ac2O and m-CPBA afforded, after removal by column chromatography of the 9/10 acetates, a mixture of the regioisomeric epoxides 1jOAc and 1kOAc (ratio 9:1, total 60%). Treatment of this mixture with Al(O-i-Pr)3 followed by CuI-catalysed Wurtz coupling of the acetates of the resulting allylic alcohols with citronellylmagnesium chloride 12a, and finally hydrogenation then provided the title acetate (overall 46% from 2).
  • Vincent Gembus, Nathalie Sala-Jung, Daniel Uguen
    2009 Volume 82 Issue 7 Pages 843-854
    Published: July 15, 2009
    Released: July 10, 2009
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    In contrast to reports in the literature, the pyridine-catalysed condensation of phenolic compounds and conjugated aldehydes to chromenes was found to be applicable to trimethylhydroquinone 2a with the result of complementary convergent approaches to the title acetate using citral 3a and dihydromyrcene 9 as precursors of the phytyl residue.
  • Toshiyuki Shigetomi, Kentaro Okuma, Noriyoshi Nagahora, Yoshinobu Yoko ...
    2009 Volume 82 Issue 7 Pages 855-859
    Published: July 15, 2009
    Released: July 10, 2009
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    The reaction of 4,4-di-tert-butyl-1,2-dithietan-3-one with triphenylphosphine afforded 1,1-di-tert-butylthiiran-2-one (86%). The reaction of 4,4-di-tert-butyl-1,2-dithietan-3-one with phenylmagnesium bromide gave S-phenyl 2-tert-butyl-2-mercapto-3,3-dimethylbutanethioate in 83% yield. The reaction of 4,4-di-tert-butyl-1,2-dithietan-3-one with tetrakis(triphenylphosphine)palladium(0) gave square-planar complex in 84% yield, whose structure was determined by X-ray crystallographic analysis.
  • Hideyuki Shimizu, Yasuhiko Kakinoya, Kazuyuki Takehira, Toshitada Yosh ...
    2009 Volume 82 Issue 7 Pages 860-869
    Published: July 15, 2009
    Released: July 10, 2009
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    Two carbazolophanes bearing benzene or naphthalene rings on the nitrogen atoms of carbazole were successfully synthesized by the intramolecular etherification of the precursor tetraols, and their photophysical properties were investigated in detail based on the absorption spectra, fluorescence spectra, fluorescence lifetimes, quantum yields, phosphorescence spectra, and transient absorption spectra. It was concluded that the carbazolophane bearing benzene rings forms carbazole excimer in both excited singlet and triplet states, while the carbazolophane bearing naphthalene rings forms carbazole excimer only in the excited singlet state and has a locally excited state of naphthalene in the excited triplet state. These results are reasonably explained by the relationship of excitation energies between carbazole and benzene (or naphthalene) and their arrangement such as the extent of overlap. The introduction of aromatic rings on the carbazole nitrogen atoms was found to affect the electronic and photophysical properties of carbazolophanes sensitively.
  • Arthit Makarasen, Masaki Kuse, Toshio Nishikawa, Minoru Isobe
    2009 Volume 82 Issue 7 Pages 870-878
    Published: July 15, 2009
    Released: July 10, 2009
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    Amino(aryl)pyrazines, a key intermediate in the synthesis of coelenterazine and its analogs, can be prepared in excellent yields by utilizing imino-O-tosylates in the Suzuki–Miyaura reaction. These imino-O-tosylates serve as a substitute for the corresponding imino-O-triflates, which are sometimes too unstable to be stored during the optimization of the reaction conditions. Aryltrifluoroborates, a coupling partner, worked well when arylboronic acids or arylboronate esters were less reactive. Aryltrifluoroborates also worked well when containing an electron-donating group attached to the aromatic ring. The study of the substituent effect of imino-O-arenesulfonates demonstrated a major difference in the rate of the reactions when changing from electron-donating groups to electron-withdrawing groups at the para position of arenesulfonates. Imino-O-arenesulfonate containing a para-bromo substituent only gave the desired coupling product leaving the para substituent of arenesulfonate untouched.
  • Shin-ichi Takekuma, Kenji Fukuda, Yasuko Kawase, Toshie Minematsu, Hid ...
    2009 Volume 82 Issue 7 Pages 879-890
    Published: July 15, 2009
    Released: July 10, 2009
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    Reaction of guaiazulene (=7-isopropyl-1,4-dimethylazulene) with 4′-hydroxyazobenzene-4-carbaldehyde in methanol in the presence of hexafluorophosphoric acid at 25 °C for 2 h gives as high as 94% yield of a new monocarbenium ion compound (3-guaiazulenyl)[4-(4-hydroxyphenylazo)phenyl]methylium hexafluorophosphate. Similarly, reactions of guaiazulene with 4′-methoxyazobenzene-4-carbaldehyde and 4′-(dimethylamino)azobenzene-4-carbaldehyde under the same reaction conditions as the above afford the corresponding new (3-guaiazulenyl)[4-(4-methoxyphenylazo)phenyl]methylium and {4-[4-(dimethylamino)phenylazo]phenyl}(3-guaiazulenyl)methylium hexafluorophosphates in 97 and 95% yields. Along with an efficient preparation of the target monocarbenium ion compounds, comparative studies on spectroscopic, chemical, and electrochemical properties of the unique products, indicating different delocalized π-electron systems, are reported. Moreover, crystal structure of {4-[4-(dimethylamino)phenylazo]phenyl}(3-guaiazulenyl)methylium tetrafluoroborate with an equiv of HBF4 molecule is documented.
  • Kenichiro Kamae, Yasushi Obora, Yasutaka Ishii
    2009 Volume 82 Issue 7 Pages 891-895
    Published: July 15, 2009
    Released: July 10, 2009
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    One-pot Baeyer–Villiger oxidation of cycloalkanones was successfully achieved by allowing them to react with hydrogen peroxide generated in situ from benzhydrol and molecular oxygen assisted by N-hydroxyphthalimide (NHPI) and 2,2′-azobisisobutyronitrile (AIBN). This method provides an alternative synthetic route to lactones from cycloalkanones using sec-alcohols and molecular oxygen assisted by NHPI.
  • Takakazu Yamamoto, Takao Sato, Takayuki Iijima, Masahiro Abe, Hiroki F ...
    2009 Volume 82 Issue 7 Pages 896-909
    Published: July 15, 2009
    Released: July 10, 2009
    JOURNALS OPEN ACCESS
    Self-assembly of polythiophenes with –C≡CR (R = alkyl, phenyl, etc.) side chains has been investigated. Seven new polymers consisting of head-to-head and tail-to-tail 2,2′-bithiophenes with –C≡CR side chains were synthesized. The new polymers include alternating copolymers between bithiophenes with –C≡C–alkyl side chains and thiophene and those between bithiophenes with –C≡C–alkyl side chains and 2,2′-bithiophene. The polythiophene main chain is considered to be coplanar because of the absence of steric repulsion between the main chain and the –C≡CR side chain. Single-crystal X-ray crystallography and DFT calculations indicated that the head-to-head- and tail-to-tail-2,2′-bithiophenes with –C≡CR side chains were coplanar. The polythiophenes with –C≡CR side chains showed a strong tendency to self-assemble, and assumed edge-on alignment and side-on alignment on the surface of substrates. Self-assembly caused a decrease in the π–π* transition energy of the polymers by 0.3–0.4 eV. A copolymer of thiophene and dialkoxy-p-phenylene showed analogous self-assembly. The polythiophenes with –C≡CR side chains showed piezochromism, with a decrease in the π–π* transition energy by about 0.2 eV at 10 GPa. Head-to-head-P3(C≡C–Dec)Th with a –C≡C–decyl side chain gave a larger optical third-order nonlinear susceptibility χ(3) than regio-regular poly(3-hexylthiophene)s.
  • Yosuke Sakamoto, Akihiro Yabushita, Masahiro Kawasaki, Tomoki Nakayama ...
    2009 Volume 82 Issue 7 Pages 910-913
    Published: July 15, 2009
    Released: July 10, 2009
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    Optical properties of iodine-containing aerosols that were produced by ultraviolet photoirradiation of a mixture gas of CH2I2 and O3 with dry air diluent have been measured using a nephelometer, a particle soot absorption photometer and a cavity ring-down spectrometer. Single scattering albedo of iodine aerosols was determined to be 0.96 ± 0.01 at around 530 nm. Chemical compositions of the aerosols associated with particle size in the range of 0.2–1 µm was measured using a laser-ionization single-particle aerosol mass spectrometer. Positive and negative ion signals of iodine and iodine oxides, IOn (n = 0–4), I2On (n = 0–6), and I3On (n = 0–1), carbon-containing compounds and HOI were detected.
  • Tatsuto Yui, Takako Tsuchino, Hiroyuki Mino, Tsutomu Kajino, Shigeru I ...
    2009 Volume 82 Issue 7 Pages 914-916
    Published: July 15, 2009
    Released: July 10, 2009
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    A remarkably stable and continuous photoinduced charge separation with a half lifetime longer than 2.5 h in ambient atmosphere was observed at the interface of mesoporous silica and titania nanosheets involving porphyrins and viologen in their nanospaces, respectively.
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