Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 60 , Issue 9
Showing 1-50 articles out of 70 articles from the selected issue
  • Koe Enmanji
    1987 Volume 60 Issue 9 Pages 3087-3092
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Bis[1-(4-dimethylaminophenyl)-2-phenylethanedithione]nickel(0) (BDN), a Q-switch dye for neodymium lasers, bleached in polymer matrix such as poly(butyl methacrylate). To elucidate the bleaching mechanism, the effect of water-soluble polymer added to dimethyl sulfoxide (DMSO) solution of BDN on the bleaching rate was investigated. BDN was reduced by a water-soluble polymer such as poly(vinyl alcohol) (PVA), starch, and cyclodextrin (CD) in DMSO. BDN bleached in DMSO solution with PVA and bleaching rate depended on the saponification number of PVA. BDN was also bleached by adding CD to DMSO solution. From the concentration dependence of CD on BDN bleaching rate, it was presumed that the vicinity of Ni of BDN is not included in β- and γ-CD, but is included in α-CD. For avoiding reduction of BDN by CD, 2,4,5-tri-O-methoxy-β-cyclodextrin (T-β-CD) was examined. BDN was not reduced by an inclusion complex of BDN with T-β-CD. The storage life of Q-switch with matrices of poly(butyl methacrylate) and polystyrene was determined. The Q-switch with polystyrene matrix having transmittance of 70.0% is expected to have transmittance of 70.4% after strage for 10 years at 25 °C.
  • Keisaku Kimura
    1987 Volume 60 Issue 9 Pages 3093-3097
    Published: 1987
    Released: June 27, 2006
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    Ultrafine metal particles with different sizes have been obtained by several preparation methods. The smallest Mg particles (the average diameter Dm of about 2 nm) were obtained by the matrix isolation method in He and the largest (Dm, 100 nm) by the conventional gas evaporation method in Ar. By changing the pressure and the kind of gas, particles with an intermediate diameter have been obtained. The size distribution of small In particles was discussed.
  • Takashi Kakiuchi, Mitsugi Senda
    1987 Volume 60 Issue 9 Pages 3099-3107
    Published: 1987
    Released: June 27, 2006
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    The liquid-junction potentials between two immiscible electrolyte solutions have been studied for the interface: R1+TPB(nitrobenzene)/R1+X(water) and R1+TPB (nitrobenzene)/Li+TPB(water), where R1+ is a tetraalkylammonium ion, TPB is tetraphenylborate ion, and X is a halide ion. These interfaces may be seen as a simplest form of either a liquid ion-exchange membrane ion-selective electrode sensing the activity of the ion in the aqueous phase or a reference electrode of a liquid membrane type reversible to the ion in the nonaqueous phase. The effects of the cationic species(R1+), the anionic species(X) and the concentration of the electrolytes on the electrical potential difference developed at the interface have been studied. These properties of the interfaces were compared with a simplified theoretical treatment of the liquid-junction potential between the two immiscible solutions. The theory can predict the basic features of the system by knowing the standard ion-transfer potentials and the diffusion coefficients of the relevant ions as well as its concentration. In the concentration range where a significant deviation from the Nernstian response of the liquid-junction potential occurred, the diffusion potential has been demonstrated to contribute significantly to the liquid-junction potential.
  • Takashi Kakiuchi, Miki Kobayashi, Mitsugi Senda
    1987 Volume 60 Issue 9 Pages 3109-3115
    Published: 1987
    Released: June 27, 2006
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    The adsorption of the hexadecyltrimethylammonium ion(HTMA+) at the polarized nitrobenzene–water interface has been studied using electrocapillary measurements. The adsorption of HTMA+ was found to be markedly dependent on the potential drop across the interface. HTMA+ exhibited no specific adsorption in the potential range where the aqueous phase is positive, whereas a strong adsorption occurred in the potential range where the electric potential in the aqueous phase is negative with respect to that in the nitrobenzene. The adsorption free energy depends linearly on the potential difference across the interface. The specific adsorption of HTMA+ significantly alters the double-layer structure. The outer Helmholtz potential in the nitrobenzene phase was inverted from negative to positive due to the adsorption of HTMA+ ions.
  • Tetsuya Osaka, Ichiro Koiwa, Keizo Yamada, Masao Nishikawa, Masahiko U ...
    1987 Volume 60 Issue 9 Pages 3117-3124
    Published: 1987
    Released: June 27, 2006
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    Electroless Ni–Mo–B alloy films from a bath using dimethylamine–borane(1/1) (DMAB) as a reducing agent were investigated. Only a small amount of Mo-complex addition to the bath decreased the boron content and increased the molybdenum content drastically. The maximum molybdenum content and maximum resistivity under as-plated conditions were obtained as 22.1 wt% and 322 μΩ cm respectively. Such a high resistivity is characteristic of Ni–Mo–B alloy films. Both crystallized and amorphous states of Ni–Mo–B alloy films, whose Mo contents were above 20 wt% with a small amount of boron, were prepared by controlling the Mo-complex concentration in the bath. The heat change properties of Ni–Mo–B alloy films were quite different from those of the electroless Ni alloy films reported previously. The resistivity of Ni–Mo–B alloy films after heat treatment at 500 or 600 °C became higher than that of those created under as-plated conditions. The structure transformation of Ni–Mo–B alloy films after heat treatment was quite different from that of ordinary electroless Ni alloy films. The Ni–Mo–B alloy film after heat treatment was confirmed by TEM observation to show a mosaic-like structure. Therefore, it was thought that such a high resistivity and such thermal properties of Ni–Mo–B alloy films are caused by such a mosaic-like structure.
  • Toshio Takayama, Isao Ando
    1987 Volume 60 Issue 9 Pages 3125-3129
    Published: 1987
    Released: June 27, 2006
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    The 29Si chemical shifts of silicon hydrides and fluorosilanes were calculated by means of the FPT method within the CNDO/2 framework. It was found that, by a small revision of the formula for the off-diagonal elements of the core Hamiltonian matrix in the CNDO/2 method, the calculated results agree well with the gross trend of the experimental values of the 29Si chemical shifts in the literature. Further, the relationship between the 29Si chemical shift and the electronic structure was discussed.
  • Tomoyuki Kohida, Masahiro Kotaka, Shin Sato, Toru Ishida, Keiji Yamamo ...
    1987 Volume 60 Issue 9 Pages 3131-3135
    Published: 1987
    Released: June 27, 2006
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    The reaction of hydrogen atoms with trifluoroethylene has been studied at room temperature by using the mercury photosensitized decomposition of hydrogen as the source of hydrogen atoms. Product analyses using gas chromatography and 1H and 19F NMR spectroscopy confirmed the 1,2-migration of a fluorine atom in the CH2F\dotCF2 radical produced by the addition of a hydrogen atom to trifluoroethylene. The rate constant of the migration was estimated to be 2×1010 s−1 from the pressure dependence of the five kinds of hexafluorobutanes produced. NMR parameters for these fluorinated compounds were determined.
  • Tsuyoshi Takiguchi, Tsutomu Nonaka
    1987 Volume 60 Issue 9 Pages 3137-3142
    Published: 1987
    Released: June 27, 2006
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    Current efficiency for the (Br)+(positive bromine species)-mediated indirect electrooxidation of alcohols to the corresponding carbonyl compounds decreased with increase in Br concentration in dichloromethane and aqueous acidic solutions, while no concentration dependence was observed in an aqueous neutral solution. These facts suggested a general and practical guideline for the indirect electrooxidation, i.e. low Br concentration is favorable in an electrolytic solution of low nucleophilicity. It was also found that the kind of (Br)+ species formed anodically in the absence of the alcohols in dichloromethane clearly depended on charge(Q) passed as follows: Br3 at Q≤2⁄3F mol−1 (1F=96480 C), Brn (n>3) at 2⁄3<Q<1F mol−1, and Br2 at Q=1F mol−1. Among these species, Br3 and Br2 seemed to be the weakest and strongest oxidizing agents, respectively. Lower efficiency for the indirect electrooxidation in higher Br concentration was rationalized as due to more predominant formation of Br3 and/or Brn with smaller n values.
  • Jun-ichi Aihara
    1987 Volume 60 Issue 9 Pages 3143-3147
    Published: 1987
    Released: June 27, 2006
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    The astronomical IR spectra of molecular origin have been attributed to compact polycyclic aromatic hydrocarbons. This interpretation can be rationalized in terms of the percent resonance energies of the excited-state species. In general, large compact polycyclic aromatic hydrocarbons are not only thermodynamically stable but also photochemically stable. These hydrocarbons have large percent resonance energies in the excited state, and are expected to survive the rough conditions in space. In contrast, relatively small aromatic hydrocarbons are greatly destabilized when they are excited electronically or deprived of two π electrons.
  • Masaki Yamada, Koji Araki, Shinsaku Shiraishi
    1987 Volume 60 Issue 9 Pages 3149-3155
    Published: 1987
    Released: June 27, 2006
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    A new type of N2O2 tetradentate ligands, 6,6′-bis(acylamino)-2,2′-bipyridines, was synthesized and their complex formations with copper(II) were investigated. They form two types of 1:1 complexes; one is the non-deprotonated type having external counter anions and the other is the deprotonated type having no external counter anions. They serve as square planar N2O2 tetradentate ligands in either case and the structures of the complexes are very similar to salen complexes. The structures and properties of these complexes were investigated and discussed.
  • Atsushi Muramatsu, Takashi Tatsumi, Hiro-o Tominaga
    1987 Volume 60 Issue 9 Pages 3157-3161
    Published: 1987
    Released: June 27, 2006
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    Highly active Mo catalysts for mixed alcohol synthesis were prepared using Fuji Davison ID silica gel as a carrier. KCl promoted the selectivity to alcohols but reduced CO conversions in particular to hydrocarbons. Productivity of alcohols was largely affected by the reaction conditions. High pressure and short contact time enhanced space-time yield of alcohols, i.e. 420 g (kg-catalyst)−1 h−1 at 5.0 MPa, 573 K, and W/F=1.4 g-catalyst h mol−1. The presence of K effectively prevented the complete reduction of Mo to metal, resulting in the increase in the production of alcohols. The study on addition of ethene and ethanol to synthesis gas revealed that the other roles of K are to retard dehydration of alcohols to alkenes and their hydrogenation to alkanes.
  • Kenichi Imaeda, Toshiaki Enoki, Zurong Shi, Peiji Wu, Naoko Okada, Hid ...
    1987 Volume 60 Issue 9 Pages 3163-3167
    Published: 1987
    Released: June 27, 2006
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    Electrical conductivities have been measured for TTCn–TTF and TTeCn–TTF. In the case of TTCn–TTF, the compounds with short alkyl chains (n=1–3) show the high resistivities above 1010 Ω cm, while the resistivities of the compounds with long alkyl chains (n≥4) decrease to 105–107 Ω cm. The relatively low resistivities of the compounds with long alkyl chains are attributed to the considerable reduction in intermolecular distance between adjacent TTF skeletons caused by intermolecular interactions through alkyl chain groups taking into account the results of their crystal structures, thermal properties and densities. As for TTeCn–TTF compounds, the carbon number dependence of resistivity is almost similar to that of TTCn–TTF in the range of large n (n≥8). Exceptionally, TTeC1–TTF exhibits noticeably low resistivity of 6.9×104 Ω cm. X-Ray diffraction study confirms that the high conductivity of TTeC1–TTF is caused by the formation of zigzag Te chains due to the presence of strong intermolecular Te–Te atomic contacts.
  • Jun-ichi Anzai, Yasushi Hasebe, Akihiko Ueno, Tetsuo Osa
    1987 Volume 60 Issue 9 Pages 3169-3173
    Published: 1987
    Released: June 27, 2006
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    Poly(vinyl chloride)/spirobenzopyran membranes doped with valinomycin or nonactin were prepared to study the photoresponse of the membrane potential in the presence of K+ or NH4+ ion. Ultraviolet (UV) light irradiation induced more than 100 mV of potential change across the membrane doped with valinomycin in the presence of 10−8–10−6 M KCl, whereas the potential change was extremely suppressed in the presence of higher KCl concentration (>10−3 M). The photoresponse of the membrane potential depended upon the direction from which the membrane was irradiated. The nonactin-doped membranes showed a similar tendency in photoresponse in the presence of NH4Cl to that observed for the valinomycin-doped membrane in the presence of KCl. The results were explained in terms of surface potential changes at the irradiated surface of the membrane, associated with the photochemical reaction of spirobenzopyran and the specific adsorption of cations to the surface of the membrane.
  • Kozue Kaibara, Hiroyoshi Inoue, Hideo Kimizuka
    1987 Volume 60 Issue 9 Pages 3175-3181
    Published: 1987
    Released: June 27, 2006
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    Transport characteristics of Na+–Ca2+ bi-ionic system with a highly selective cation-exchange membrane were investigated on the basis of nonequilibrium thermodynamic theory. As a principal transport parameter, the membrane permeability matrix or membrane conductance matrix can be estimated from the membrane potential, conductance, and ion flux data. Significances of diffusional and electroconductive processes of ion transport across membrane were systematically discussed in terms of these matrix elements. Partial contributions of inter-cationic (Na+–Na+, Na+–Ca2+, and Ca2+–Ca2+) correlations to the membrane transport process of ions were examined by means of comparing the estimated values of corresponding matrix elements. It was suggested that Ca2+ ions, of which membrane concentrations are kept at high level independently of the Na+/Ca2+ concentration ratio of external aqueous solutions, play a critical role in the membrane transport phenomena. Participations of Cl transport in the cation-exchange processes were also discussed on the basis of membrane conductance matrix theory.
  • Manabu Igawa, Takeshi Yoshida, Chiaki Ohtake, Takashi Hayashita
    1987 Volume 60 Issue 9 Pages 3183-3188
    Published: 1987
    Released: June 27, 2006
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    Clogging and gel-layer formation during membrane filtration affect the concentration of ions in the filtrate as well as the concentration of suspended solids. The flow rate analysis and the observation of the filter surface with a scanning electron microscope show that a gel-layer is formed subsequently after the clogging. Humic acids, fulvic acids, metal hydroxides, and soft particles dispersed in natural waters cause the clogging and hence the gel-layer formation. Cross-flow filtration decreases the rate of the clogging and the gel-layer formation and gives little rise to the filtration effects on analytical results.
  • Kameo Asada, Keiko Ema, Takashi Iwai
    1987 Volume 60 Issue 9 Pages 3189-3193
    Published: 1987
    Released: June 27, 2006
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    Reaction of UO2F2 with UF5 at 400 °C under UF6-pressure of 3 atm followed by evaporation of excess UF5 has yielded a greenish white residue. Its X-ray diffraction pattern and infrared spectrum are sufficiently unique to establish that this material is a true compound. Its chemical formula has been shown to be U2O2F7, on the grounds of chemical analysis and thermal decomposition. The oxygen content was determined directly by means of 18O isotopic dilution method based on the combustion of the samples with BrF5.
  • Hirofumi Tsukada, Hiroshi Hara, Kiyoshi Iwashima, Noboru Yamagata
    1987 Volume 60 Issue 9 Pages 3195-3198
    Published: 1987
    Released: June 27, 2006
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    Atmospheric aerosols were collected onto a Fluoropore filter in order to determine the iodine by means of instrumental neutron activation analysis. The collection filter was found to be the best material among the nine filters examined, for it has the lowest blank values for iodine as well as for other halogens and sodium. The iodine concentrations in Tokyo were found to be 1.7–12.7 ng m−3. Of the soluble iodine, 10% or less was in the form of IO3.
  • Shinji Izumoto, Katsuhiko Miyoshi, Hayami Yoneda
    1987 Volume 60 Issue 9 Pages 3199-3205
    Published: 1987
    Released: June 27, 2006
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    Reversed-phase ion-pair chromatography (RPIPC) was applied to the optical resolution of amine complex cations of the type [Co(N)6]3+ using either bis(μ-d-tartrato)diantimonate(III) ion, [Sb2(d-tart)2]2− or its arsenic analog, [As2(d-tart)2]2− as an ion-pairing reagent. With either reagent, efficient optical resolution was attained for [Co(en)3]3+, [Co(tn)3]3+, [Co(sen)]3+, [Co(sep)]3+, and [Co(diNOsar)]3+ (en=ethylenediamine, tn=trimethylenediamine, sen=1,1,1-tris[[(2-aminoethyl)amino]methyl]ethane, sep=1,3,6,8,10,13,16,19-octaazabicyclo[6.6.6]icosane, and diNOsar=1,8-dinitro-3,6,10,13,16,19-hexaazabicyclo[6.6.6]icosane). Dependence of retention volumes and separation factors of these complexes on the concentration and the counterion of the ion-pairing reagents was examined with Na+, Me4N+, and Et4N+ employed as counterions. Experimental results were discussed with reference to those obtained by means of normal-phase ion-exchange chromatography (NPIEC) using the same eluents. It was concluded that [As2(d-tart)2]2− serves as a more effective eluent in both RPIPC and NPIEC than [Sb2(d-tart)2]2−, and that RPIPC is a much more useful tool for the optical resolution of the [Co(N)6]3+-type complex cations than NPIEC.
  • Akiko Furuhashi, Tomoko Inayoshi, Akira Ouchi
    1987 Volume 60 Issue 9 Pages 3207-3211
    Published: 1987
    Released: June 27, 2006
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    The title complex was newly synthesized and its crystal and molecular structure was determined by the single-crystal X-ray diffraction technique. The crystal is monoclinic, space group C2⁄c, a=16.005(4), b=10.520(2), c=15.338(4) Å, β=114.68(2)°, and Z=4. In the complex, the central metal atom is hexa-coordinated being in a deformed octahedral geometry: Two 2-(2-benzoxazolyl)phenolato ligands form six-membered chelate rings being coordinated with their oxazolyl nitrogen and phenolato oxygen atoms, while the nitrate ion acts as a bidentate with its two oxygen atoms. As the benzoxazolyl ring is parallel and overlapped with that of the neighboring complex along the c-axis, where the interplane distance is 3.557 Å, some interaction between the rings is expected. As this complex in solid state is deep violet, almost black, in color, some charge-transfer bands are expected to exist in its electronic spectra. The bis[2-(2-benzothiazolyl)phenolato]nitratoiron(III) was found to be isomorphous to the title complex.
  • Kazuo Kojima, Jiro Matsuda, Norimichi Kojima, Toshiro Ban, Ikuji Tsuji ...
    1987 Volume 60 Issue 9 Pages 3213-3217
    Published: 1987
    Released: June 27, 2006
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    The ligand-field spectra for the cobalt complexes in the single crystals of K3H2[CoIIIW12O40]·16H2O and K4H2[(COII, ZnII)W12O40nH2O have been observed at several temperatures above 1.4 K and assigned under D2 site symmetry. In the spectrum of the elongated CoIIIO4 complex, two absorption bands of 8250 and 8953 cm−1 strengthen with increasing temperature by vibronic mechanism. The X-band ESR spectra of both complexes have also been measured at 77 K. The signal from the Co(III) complex is not observed. The signal of the high-spin Co(II) complex of tetrahedral symmetry is unequivocally observed even at relatively high temperature of 77 K. From the analysis of the ESR spectrum, it is concluded that the CoIIO4 tetrahedron of D2 symmetry is flattened and deviated slightly from axial symmetry.
  • Kenichiro Nakashima, Yukari Nagaoka, Shin’ichi Nakatsuji, Takahi ...
    1987 Volume 60 Issue 9 Pages 3219-3223
    Published: 1987
    Released: June 27, 2006
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    The fluorescence behavior by a complexation of “crowned” benzothiazolylphenols (CBTP and CBBTP) with alkali and alkaline earth metal ions in the presence of triethylamine was examined in various organic solvents. The fluorescence spectra of these CBTP– and CBBTP–metal ion complexes were measured in order to compare mutually both their excitation and emission maxima together with the relative fluorescence intensities (RFI). Both the Li–CBTP and Li–CBBTP complexes showed considerably higher RFI than the other metal complexes. The stability of the fluorescence intensity and various conditions for the determination of Li+ or Ca2+ were fully examined. On the basis of these experiments, fluorometric methods were developed for a sensitive determination of trace amounts of Li or Ca by using the crown compounds (CBTP and/or CBBTP). Moreover, a thin-layer chromatographic method for the separation of Li from other metal ions was examined in order to selectively determine Li by using CBBTP.
  • Tsugikatsu Odashima, Minoru Yamada, Naoki Yonemori, Hajime Ishii
    1987 Volume 60 Issue 9 Pages 3225-3231
    Published: 1987
    Released: June 27, 2006
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    Four kinds of 1-phthalazinylhydrazones have been synthesized and their chromogenic properties and reactivities with metal ions investigated. Of the synthesized hydrazones, di-2-pyridylmethanone 1-phthalazinylhydrazone (DPPhH) proved to be the best chromogenic reagent for nickel. It reacts with nickel(II) at pH above 2.5 to form a 1:2 (nickel–ligand) complex extractable into various organic solvents. The extracted species into benzene has an absorption maximum at 500 nm and gives a maximum and constant absorbance in the pH range 4.3–10.7. Beer’s law is obeyed over the range 0.1–1.0 μg cm−3 of nickel. The molar absorptivity (ε) and the sensitivity for an absorbance of 0.001 are 5.4×104 dm3 mol−1 cm−1 and 1.08 ng cm−2 at 500 nm, respectively. A sensitive and selective extraction-spectrophotometric method for the determination of nickel at μg cm−3 levels is proposed and has been applied successfully to the analysis of iron and steel samples. The proposed method can be made more sensitive by the introduction of an analogue-derivative spectrophotometric technique.
  • Masunobu Maeda, Osamu Hisada, Yoshiaki Kinjo, Kaname Ito
    1987 Volume 60 Issue 9 Pages 3233-3239
    Published: 1987
    Released: June 27, 2006
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    The ion product of water at 298.15 K was evaluated according to the Pitzer ionic interaction theory in LiCl, NaCl, KCl, KNO3, LiClO4, and NaClO4 media of different concentrations (0.1–5 mol kg−1) and in artificial seawaters at different salinities (20–44%). The Pitzer approach was also applied to the estimation of the ion products of water in NaCl media at temperatures (288–373 K) different from 298.15 K. The theoretically evaluated values showed reasonable agreement with experimental ones.
  • Yonezo Maeda, Masaaki Aramaki, Yoshimasa Takashima, Michiharu Oogai, T ...
    1987 Volume 60 Issue 9 Pages 3241-3246
    Published: 1987
    Released: June 27, 2006
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    Mössbauer studies of iron oxides formed on the surface of fine iron particles (acicular type about 15 nm in diameter and 100 nm long) and of an oxidation process in air have been done in the temperature range from 4.2 to 298 K. The Mössbauer spectra indicate that the main component of the oxide layers 2.1–5.6 nm thick, except for a few oxide layers from the iron surface, is composed of fine particles of γ-Fe2O3, and that fine iron oxide particles are produced freshly during the oxidation process at 110 °C in air with the growth of iron oxide particles. It is concluded that an oxide layer 2.1 nm thick is formed on the iron surface if a fresh iron surface is exposed to air at room temperature.
  • Hirotaka Nagao, Kimitake Aoyagi, Yasuhiko Yukawa, F. Scott Howell, Mas ...
    1987 Volume 60 Issue 9 Pages 3247-3254
    Published: 1987
    Released: June 27, 2006
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    Under mild conditions, trans-[RuCl(O)(py)4]+ in alcohols changes to an alkoxo complex, trans-[RuCl(OR)(py)4]+, The hydroxo complex, trans-[RuCl(OH)(py)4]+, which retains the reactive oxygen of the oxo complex, was found to exist as a precursor in the formation of the alkoxo complex. The reaction progress was traced by spectrometrical and 18O-labelling experiments.
  • Mitsuaki Narita, Masamitsu Doi, Takao Nakai
    1987 Volume 60 Issue 9 Pages 3255-3259
    Published: 1987
    Released: June 27, 2006
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    In connection with the relationship between the conformation and solubility of peptide intermediates having polar side chains, IR spectroscopic conformational analysis of peptide fragments of human hemoglobin α-chain (123–136) was performed in dichloromethane. In dichloromethane, the conformational behavior of the peptide fragments was, in essence, dependent on their amino acid sequences, and Boc–Ser(Bzl)–Thr(Bzl)–Val–Leu–OPac through Boc–Ala–Ser(Bzl)–Val–Ser(Bzl)–Thr(Bzl)–Val–Leu–OPac had predominantly unordered structures including some intramolecular hydrogen bonds, while Boc–Ala–Ser(Bzl)–Leu–Asp(OBzl)–Lys(Z)–Phe–Leu–OPac had successive intramolecular hydrogen bonds, probably corresponding to an α-helical structure. On the other hand, in carbon tetrachloride, the conformation of Boc–Val–Ser(Bzl)–Thr(Bzl)–Val–Leu–OPac and Boc–Ser(Bzl)–Val–Ser(Bzl)–Thr(Bzl)–Val–Leu–OPac had a typical β-sheet structure. These results are discussed on the basis of the amino acid sequences of the peptide fragments.
  • Michihiko Noguchi, Manabu Yoshioka, Shinji Kakimoto, Shoji Kajigaeshi
    1987 Volume 60 Issue 9 Pages 3261-3267
    Published: 1987
    Released: June 27, 2006
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    The oxidation of 3a,4-dihydro-1-isoindolinone derivatives with MCPBA was carried out regio- and stereoselectively to afford the 5,6-epoxide products 2. The ring opening reaction of 2 with amines, alcohols, and sodium azide gave homoallyl alcohol type of products, derived from the ring opening at C-5 of 2. Lithium (cyano-C)methylcuprate reacted with 2 to give homoallyl and/or allyl alcohol, which is due to the conjugate addition to the C-7a position. This approach for selective introduction of functional groups into the heterocycles was extended for 3,4,4a,5-tetrahydro-1(2H)-isoquinolone system.
  • Kazuya Ohga, Yoshiaki Kurauchi
    1987 Volume 60 Issue 9 Pages 3269-3275
    Published: 1987
    Released: June 27, 2006
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    Zn(II) complexes of pyridoxal–α-amino acid Schiff bases showed photochromic behavior in methanol. Spectral studies revealed that intramolecular nucleophilic attack of 5′-hydroxyl group on imine linkage forms cyclic α-amino ether intermediates which thermally return to the original complexes. The photochromism was characteristic of complexes having a 1:1 ligand–metal ratio. Analogous photochromism was also observed with the Cd(II) complex of N-pyridoxylidenevaline having a fully occupied d-orbital like the Zn(II) complexes, whereas no photochromism was observed with other transition metal complexes such as Ni(II), Cu(II), Mn(II), and Co(II) complexes.
  • Tadashi Shiraiwa, Yujin Sado, Masamitsu Komure, Hidemoto Kurokawa
    1987 Volume 60 Issue 9 Pages 3277-3283
    Published: 1987
    Released: June 27, 2006
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    Infrared spectrum, solubility, and ternary solubility diagram indicated that DL-thiazolidine-4-carboxylic acid (DL-THC) is a conglomerate at room temperature. The free energy of critical nucleation in supersaturated solutions for the crystallization of D- and L-THC was examined to resolve DL-THC efficiently by preferential crystallization. Successive preferential crystallization of DL-THC was experimented at 20 °C for an aqueous racemic solution with a supersaturation of 150%, and D- and L-THC with optical purity of 96–100% were obtained in the range of resolution of 58–76%. The optical resolution was more successfully done in 1 mol dm−3 aqueous glycine to give D- and L-THC with optical purity of 93–99% in the degree of resolution of 77–87%. Recrystallization of D- and L-THC obtained with a succeeding treatment with hydroxylamine hydrochloride gave D- and L-cysteine with 100% optical purity.
  • Shun-Ichi Murahashi, Yo Mitsue, Tatsuo Tsumiyama
    1987 Volume 60 Issue 9 Pages 3285-3290
    Published: 1987
    Released: June 27, 2006
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    The reaction of β-amino ketones with bis(acetonitrile)dichloropalladium(II) in the presence of triethylamine gives the corresponding enaminones regioselectively. The cyclic β-amino ketones can be converted into the corresponding exocyclic enaminones. The enaminones thus obtained are versatile synthetic intermediates. The reaction of (E)-enaminones with organocuprates gave the corresponding (E)-α,β-unsaturated ketones.
  • Norihiro Tokitoh, Renji Okazaki
    1987 Volume 60 Issue 9 Pages 3291-3297
    Published: 1987
    Released: June 27, 2006
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    A new and versatile synthetic intermediate, α-siloxy amine was prepared in situ by the base-promoted rearrangement of a siloxyammonium salt obtained by treatment of a tertiary amine N-oxide with trialkylsilyl trifluoromethanesulfonate. The best combination of the base and silylating reagent was found to be methyllithium and t-butyldimethylsilyl trifluoromethanesulfonate. The reactions of α-siloxy amines with acyl halides and haloformates gave the corresponding amides and carbamates in moderate to good yields, respectively. Treatment of α-siloxy amines with acetic acid resulted in a direct dealkylation to free secondary amines. Fluoride induced alkylation of α-siloxy amines using alkyl halides as electrophiles leading to tertiary amines was also examined and demonstrated to be a new transalkylation method of amines.
  • Kunio Mochida
    1987 Volume 60 Issue 9 Pages 3299-3306
    Published: 1987
    Released: June 27, 2006
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    The reactions of trialkylstannane anions R3Sn with arylstannanes ArSnR3′ have been investigated; trialkylstannane anions with arylstannanes at 50 °C gave substitution products ArSnR3 in good yields. Most of these substitution products are diverted to reduction products ArH when t-butylamine for trapping free anionoids is present in the reaction mixture. These results are consistent with an initial tin–alkali metal exchange or an electron-transfer forming aryl anions and distannanes which subsequently react to the substitution products. Aryl radical intermediates by an electron-transfer process are also important in the reactions of trialkylstannane anions with electron-withdrawing groups-substituted arylstannanes, 1-naphthylstannanes, diphenylstannanes, and triphenylmethylstannane as good electron acceptor substrates.
  • Teruo Umemoto, Yoshihiko Gotoh
    1987 Volume 60 Issue 9 Pages 3307-3313
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    (1H,1H-Perfluoroalkyl)phenyl- and -(p-fluorophenyl)iodoniurn triflates, fluorosulfate, sulfate (3)–(7) were synthesized in good yields by the oxidation of 1-iodo-1H,1H-perfluoroalkanes (RfCH2I) with trifluoroperacetic acid followed by treatment with triflic acid and benzene or fluorobenzene. (1H,1H,5H,5H-Perfluoropentane-1,5-diyl)bisphenylbisiodonium triflate was synthesized similarly. (trans-1H-Perfluoro-1-alkenyl)phenyliodonium triflates (11) were synthesized by dehydrofluorination of 3 with a base in good yields. Thermolysis of 3 produced 1H,1H-perfluoroalkyl triflate and iodobenzene, while 11 gave (Z)-1-iodo-1H-perfluoro-1-alkene and phenyl triflate. The thermolysis experiment, including (perfluoroalkyl)phenyliodonium triflate (17), demonstrated that the C–I bond strength of the trivalent iodine compounds increased in the order of RfCH2–I, Rf–I<Ph–I<RfCF=CH–I. The ionic mechanism containing RfCH2+, Ph+, and Rf+ for the thermal decomposition of 3, 11, and 17, respectively, was proposed. The reactivities of 3 and 11 to such nucleophiles as phenoxide, alkoxide, and alkanethiolate anions were studied and compared with that of 17. Remarkable changes in the reactivity were found depending on the nature of the fluoro-alkyl and -alkenyl groups. The reaction of 11 with the oxide anions yielded (2-phenoxy- and -alkoxy-1H-perfluoro-1-alkenyl)phenyliodonium triflates.
  • Tetsuo Komori, Tsutomu Nonaka, Toshio Fuchigami, Kunmao Zhang
    1987 Volume 60 Issue 9 Pages 3315-3320
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    When amino acid N-carboxy anhydrides (NCA’s) were polymerized with various electrogenerated base (EGB) catalysts, the yield of poly(amino acid)s remarkably increased and the reaction time was extremely shortened compared with the conventional method using triethylamine catalyst. This novel polymerization method was successfully applied to the copolymerization of different kinds of NCA’s and to the preparation of poly(amino acid)–urethane copolymers. NCA’s were also polymerized with the EGB’s in the matrix of polypyrrole simultaneously formed by the anodic polymerization of pyrrole to provide electroconductive poly(amino acid)–polypyrrole complex films which were stable in the air and flexible.
  • Tadashi Suehiro, Seiichi Masuda, Ryuichi Nakausa, Masamichi Taguchi, A ...
    1987 Volume 60 Issue 9 Pages 3321-3330
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The decay processes of aryldiazenyl radicals were studied by using a time-resolved ESR method. The first order rate constants of decomposition were determined at −117–−48 °C in cyclopropane solutions in the presence or absence of olefins. Aryldiazenyl radicals were relatively persistent and the k1 of phenyldiazenyl-d5 at −96 °C in cyclopropane was 34 s−1. The k1 of 20 aryldiazenyl radicals at −96 °C afforded a ρ value of +1.53 (r=0.91) in a Hammett plot. Activation energies ranged from 46.2 to 25.2 kJ mol−1 and the frequency factors, log A, from 13.2 to 8.2 s−1. The second-order decay rates were measured at the initial period of the decay process at lower temperatures, in a batch system (cyclopropane) and in a flow system (isohexane). The rate constant of phenyldiazenyl-d5 in cyclopropane was 9.2·10−5 M−1 s−1 at −93 °C and the Arrhenius parameters were Ea=23.5 kJ mol−1 and logA=12.77 M−1 s−1, respectively.
  • Masanobu Kojima, Hirochika Sakuragi, Katsumi Tokumaru
    1987 Volume 60 Issue 9 Pages 3331-3336
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Photoexcitation of contact charge-transfer (CCT) pairs of 1-arylcyclohexenes 1 (aryl: phenyl, 4-methylphenyl, and 4-methoxyphenyl) and oxygen in acetonitrile and benzene gave 1,2-epoxy-1-arylcyclohexanes 2 as major products together with 2-aryl-2-cyclohexen-1-ols and acetophenones 4. Similar irradiation of the CCT pairs in methanol/acetonitrile afforded mainly 2-aryl-2-methoxycyclohexanols instead of 2 and small amounts of 1-aryl-1-methoxycyclohexanes, 2-aryl-2-cyclohexen-1-ones, and 4. The formation of these products can be explained by photoinduced electron transfer in the excited CCT pairs generating radical cations of 1 and superoxide anions.
  • Yoshio Ito, Yoshikazu Kimura, Shiro Terashima
    1987 Volume 60 Issue 9 Pages 3337-3340
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The 1β-methylcarbapenem key intermediate, (3S,4S)-3-[(R)-1-(t-butyldimethylsilyloxy)ethyl]-4-[(R)-1-carboxyethyl]-2-azetidinone, was prepared from (S)-methyl 3-hydroxy-2-methylpropionate by employing 1,3-dipolar cycloaddition of the chiral nitrone with benzyl crotonate as a key reaction.
  • Yun Chen, Kazuhiko Saigo, Noriyuki Yonezawa, Kouzou Tachibana, Masaki ...
    1987 Volume 60 Issue 9 Pages 3341-3345
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Optically active polyamides (3a–f) and O-methylated polyamides (5a,d,e), derived from (−)-anti head-to-head coumarin dimer [(−)-1], were absorbed on macroporous silica gel particles and used as chiral stationary phases for direct resolution of racemates (6–13) having aromatic moiety by high-performance liquid chromatography. Polyamide 3a and 3e could resolve 6–10 and 9–13, respectively (separation factor α>1.03), and 3d showed especially high selective recognition ability to 7 (α=1.63). However, 3c,f and 5a showed no resolution ability to all of the racemates. The high recognition ability of 3a is attributed mainly to the difference in stability between the diastereomeric complexes formed by the simultaneous interaction of 3a with the racemates. The recognition ability of polyamides derived from piperazine (3d, 5d) and 1,4-phenyl-enediamine (3e, 5e) seems to be attributed not only to the simultaneous interaction but also to their ordered conformations in the film state.
  • Otohiko Tsuge, Kazunori Ueno, Shuji Kanemasa, Kiyotaka Yorozu
    1987 Volume 60 Issue 9 Pages 3347-3358
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The 2-azaallyl anions derived from N-(1-cyanoalkyl)imines and DBU undergo Michael addition or alkylation to produce N-(1-alkylated 1-cyanoalkyl)imines. The Michael addition of some aryl-substituted imines are highly diastereoselective. The alkylated Michael adducts are converted into lactams through a hydrolysis and recyclization sequence. Base-induced cyclization furnishes 1-pyrrolines through a cyclization and HCN elimination sequence. In the latter reaction, 4,5-cis-1-pyrrolines are selectively produced when the adducts are treated with LDA in the presence of lithium iodide.
  • Otohiko Tsuge, Shuji Kanemasa, Kiyotaka Yorozu, Kazunori Ueno
    1987 Volume 60 Issue 9 Pages 3359-3366
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Lithiation of N-(1-cyanoalkyl)imines with LDA generates new N-lithiated azomethine ylide 1,3-dipoles which show enhanced reactivity toward dipolarophiles. They undergo exclusively regio- and stereoselective 3+2 cycloaddition reaction with α,β-unsaturated esters to give 1-pyrrolines after the elimination of LiCN. Metallic bases other than LDA can be also effective. Such high regio- and stereoselectivity is explained by the involvement of N-metalated azomethine ylides.
  • Tooru Inoue, Toshihiro Yamase
    1987 Volume 60 Issue 9 Pages 3367-3372
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Ternary compounds (Chevrel phase compounds) of molybdenum CuxMo6S8 were prepared by sintering mixed powders of MoS2, Mo, and CuS and employed as electrodes in aqueous solutions. Electrochemical polarization of the electrodes gives rise to intercalation and deintercalation processes of Cu+, resulting in deformative change in crystal structure of the compounds. The lattice constants of rhombohedral unit cells of the compounds are ar=6.66 Å, αr=96°, and Vr=290 Å3 for the intercalated compound Cu4Mo6S7.8, and ar=6.43 Å, αr=91.2°, and Vr=267 Å3 for the fully deintercalated Mo6S7.8. Both the copper(I) composition and the crystal structure of CuxMo6S7.8 can be controlled by the electric quantity in electrochemical redox treatment. Structure deformation results from change in electronic distribution of crystal, as well as in charge density of a Mo octahedral cluster, due to electrolysis.
  • Yoshiharu Usui, Hiroshi Koike, Yoshimi Kurimura
    1987 Volume 60 Issue 9 Pages 3373-3378
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The maximum quantum yield of 4.5 was evaluated from the kinetic analysis for the Methylene Blue-sensitized oxygenation of 2,5-diphenylfuran, and the contribution of a chain process to produce the furan endoperoxide was suggested. After the photoreaction, the thermolysis of the endoperoxide occurred to regenerate 2,5-diphenylfuran and singlet oxygen and to produce cis-1,2-dibenzoylethylene simultaneously. The activation energy of singlet oxygen recovery was estimated to be 18.5 kcal mol−1. The reversible conversion of singlet oxygen took place efficiently with thiazine and xanthene dyes. A concerted dissociation of singlet oxygen from the endoperoxide was supposed from the negative value of activation enthropy (−9.8 e.u.) for the reaction.
  • Kazufumi Kato, Kouichiro Kanda, Harumi Kondo, Kunio Esumi, Kenjiro Meg ...
    1987 Volume 60 Issue 9 Pages 3379-3383
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    An emulsion polymerization of styrene in the presence of an amino-acid type amphoteric emulsifier (Nε-lauroyl-Nα,Nα-dimethyllysine (DMLL)) was carried out at pH 7.0. The stability of mixed dispersions containing the latex particles prepared with DMLL and titanium dioxide (TiO2) was then discussed as a function of the pH in a mixed dispersed solution. The zeta-potential of the synthesized latex particles was significantly dependent on the pH and showed the existence of an isoelectric point (IEP) at pH 4.5. On the other hand, TiO2 particles had their IEP at pH 8.5. Below pH 4.5 and above pH 8.5, the mixed dispersions of the synthesized latex particles and TiO2 particles were well-dispersed because of their electric repulsion. In the range of pH 4.5–8.5, where the latices were negatively charged, while the TiO2 were positively charged, at low concentrations of the latex particles the mixed suspension was dispersed, but with an increase in the number of latex they heterocoagulated and were then redispersed at high concentrations of the latex particles. The mechanisms of these processes are discussed.
  • Kiyofumi Murakami, Yasuo Fujisaki, Takayuki Sano
    1987 Volume 60 Issue 9 Pages 3385-3390
    Published: 1987
    Released: June 27, 2006
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    The mechanism of the binding of phenylbutazone(4-butyl-1,2-diphenyl-3,5-pyrazolidinedione) to human serum albumin has been investigated by kinetic experiments using both optical absorption and circular dichroism (CD) stopped-flow methods. Three distinct processes were found to exist by the absorption technique; one of these was within the dead time of the apparatus and other two slow processes were at around 10−2 and 1 s, of which the relaxation times were determined. On the other hand, only two processes, which correspond in time range to the first and third processes seen by optical absorption, were found using CD technique. By examining the concentration dependence of the reciprocal relaxation time of each process and by taking account of the binding isotherm, a binding mechanism has been proposed. According to the elucidated reaction scheme, successive binding of two molecules of phenylbutazone is followed by a conformational change which destabilizes one of the bound species. The detailed nature is discussed in the light of the circular dichroism change of each process.
  • Chakrapani P. Patnaik, Surendra Nath Mohapatro, Akhil Krishna Panigrah ...
    1987 Volume 60 Issue 9 Pages 3391-3395
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The kinetics of oxidation of acetylacetone by peroxomonophosphoric acid and hydrogen peroxide have been investigated in the pH range 8–13.7. The oxidations by peroxomonophosphoric acid at 308 K and I=0.6 mol dm−3 follow the rate expressions,
    (i) −\fracd[PMPA]Tdt={k1[A]+k2[A]}[HPO52−]
    in the pH range 8–10.63, where k1=1.96 dm3 mol−1 s−1 and k2=0.177 dm3 mol−1 s−1, and
    (ii) −\fracd[PMPA]Tdt={k3[A]+k4[A]}[HPO52−]+{k5[A]+k6[A]}[PO53−]
    in the pH range 11.5–13.7, where k3=30.4 dm3 mol−1 s−1 and k6≈0. The rate law for hydrogen peroxide oxidations in the pH range 9.2–13 at 308 K and I=0.1 mol dm−3 is given by,
     −\fracd[Hydrogen peroxide]Tdt={k7[A]+k8[A]}[H2O2]+{k9[A]+k10[A]}[HO2]
    the k7 and k10 values being 0.393 dm3 mol−1 s−1 and 0.143×10−2 dm3 mol−1 s−1 respectively. A and A represent the diketo and enol form of acetylacetone respectively. The kinetic data and activation parameters are consistent with nucleophilic attack by peroxo species on both diketo and enol form of acetylacetone followed by oxygen–oxygen bond fission.
  • M. Shanmugam Ramachandran, T. Subburamiyer Vivekanandam
    1987 Volume 60 Issue 9 Pages 3397-3404
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The kinetics of oxidation of amino acids in aqueous medium were reinvestigated. The rate of oxidation follows second order with respect to chloramine-T (CAT) and an inverse dependence on [p-toluene-sulfonamide] (RNH2). At constant [RNH2] the rate of the reaction can be represented as (in the absence of chloride ion)
    \frac−d[CAT]dt=ka[CAT]2+kb\frac[Amino Acid][CAT]2[H+]+kc\frac[Amino Acid]2[CAT]2[H+]2.
    A linear relationship exists between pK1 and the rate constants. This shows the electrophilic attack of the oxidant at the carboxylato group of the amino acid. The effect of chloride ion on kobsd is catalytic. The mechanisms of the reactions are discussed in terms of the kinetic results.
  • Elsayed S. H. El Ashry, Mahmoud A. Nassr, Yeldez El Kilany, Ahmed Mous ...
    1987 Volume 60 Issue 9 Pages 3405-3409
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The synthesis of some acyclic C-nucleoside analogs possessing thiadiazole rings was achieved by the heterocyclization of the 4-arylthiosemicarbazones of D-galactose, D-glucose, D-mannose, D-arabinose, and lactose, Acetylation of the thiadiazoles afforded the corresponding 2-(N-acetylarylamino)-5-polyacetoxyalkyl-1,3,4-thiadiazoles and periodate oxidation gave the corresponding 5-(arylamino)-1,3,4-thiadiazole-2-carbaldehyde.
  • Shafiullah , Ansari M. Rafiuddin, Shakir Husain
    1987 Volume 60 Issue 9 Pages 3411-3414
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Reaction of nitrosyl chloride gas at 0 °C with 3,5-cholestadiene (1) provided 3,6β-dinitro-5-chloro-5α-cholest-3-ene (4) and with 3α,5-cyclo-5α-cholestan-6-one (2) afforded 3β-chloro-5-nitro-5α-cholestan-6-one (7) and 3β-chloro-6-nitrato-5-cholestene (8). Similar reaction with 6-hydroxylimino 3α,5-cyclo-5α-cholestane (3) gave 3β,6-dichloro-5-cholestene (10), 3β-chloro-6-nitratoimino-5α-cholestane (11) and 3β,5-dichloro-6-nitroimino-5β-cholestane (12). Compound 12 upon hydrolysis furnished 3β,5-dichloro-5β-cholestan-6-one (14). The structures of these compounds were established on the basis of their spectral properties, and some pertinent chemical transformations. Mechanisms for the formation of some unusual products are discussed.
  • M. Angeles Aramendía Lopidana, Victoriano Borau Bolos, Cesar Ji ...
    1987 Volume 60 Issue 9 Pages 3415-3419
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    In this work we have carried out the reduction of aromatic nitro compounds bearing different substituents with gaseous hydrogen, over a Pt catalyst (3% by weight) supported on a SiO2–AlPO4 system. The catalyst was obtained by impregnation, the impregnating metal salt being reduced with α-phellandrene. The kinetic data found allow us to describe the reduction of nitrobenzene as a Langmuir–Hinslwood kinetic. The sequence of reaction rates for the different nitro compounds assayed conforms to the Hammett–Taft equation, which allows relating the electron density of the aromatic ring to the reduction rate of the nitro group. Finally, we propose mechanism for the process, characterized by the absence of intermediates with net charges.
  • Takashi Sakai, Kazuyoshi Miyata, Kazuomi Hondo, Masanori Utaka, Akira ...
    1987 Volume 60 Issue 9 Pages 3421-3422
    Published: 1987
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    β-Phenyl α,β-unsaturated carbonyl compounds were conveniently reduced to the corresponding saturated aromatic compounds by heating with t-BuCl–Nal in acetonitrile.
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