bluuebunny/crossref_metadata_2025 huggingface dataset:
Water-Ethanol Clusters at the Liquid Surface under Atmospheric Pressure Observed by Liquid Ionization Mass Spectrometry
Authors: Tsuchiya Masahiko , Li Yaming , Shirasaka Jingo , Kaneko Takeo
Published: March 2006

By controlling the flow rate of a sample solution, information about clusters existing at the liquid surface were obtained by liquid ionization (LI) mass spectrometry. The relative abundances of binary cluster ions, (C2H5OH)m(H2O)nH+, with large m and n increased with the flow rate, while the abundances of ethanol cluster ions, (C2H5OH)mH+, increased by decreasing the flow rate. Molar ratios of water to ethanol observed were much higher than those observed by other methods.
DEAE-Dextran Enhanced Firefly Bioluminescent Assay of ATP
Authors: Kamidate Tamio , Kinkou Toshikazu , Watanabe Hiroto
Published: March 2006

Diethylaminoethyl (DEAE) - Dextran (Dx) enhanced the intensity of bioluminescence from firefly luciferase-luciferin reaction with adenosine-5′-triphosphate (ATP). The detection limit for ATP was 5 × 10−12 M in the presence of DEAE-Dx, and was improved a factor of three times compared to that in the absence of DEAE-Dx.
Catalytic Degradation of Polypropylene into Liquid Hydrocarbons Using Silica-Alumina Catalyst
Authors: Sakata Yusaku , Uddin Md Azhar , Koizumi Kazuo , Murata Katsuhide
Published: March 2006

The degradation of polypropylene (PP) was carried out at 380 °C by batch operation using silica-alumina catalyst in 1) liquid phase contact and 2) vapor phase contact. For liquid phase contact, the liquid hydrocarbon products with a yield of 69 wt% had a boiling points (BP) range of 36 to 270 °C, equivalent to the BP of normal paraffins n-C6 to n-C15. For vapor phase contact, the yield of liquid products was much lower (54 wt%) and the rate of liquid recovery was much slower.
An Efficient General Synthesis of 1-Amino-2-naphthalenecarboxylic Acid Derivatives Based on a Tandem Conjugate Addtion-Enolate Nitrile Coupling Sequence
Authors: Kobayashi Kazuhiro , Takada Keiichiro , Tanaka Hiroto , Uneda Tomokazu , Kitamura Tomohide , Morikawa Osamu , Konishi Hisatoshi
Published: March 2006

Reaction of o-(α-lithioalkyl)benzonitriles with α,β-unsaturated carboxylic acid derivatives produced 1-amino-3,4-dihydro-2-naphthalenecarboxylic acid derivatives through the tandem conjugate addition-enolate nitrile coupling sequence, which in turn were converted into 1-amino-2-naphthalenecarboxylic acid derivatives on dehydrogenation with palladium on activated carbon.
Thermal Stabilization of Polypyrrole by Incorporation of Aromatic Sulfonate Derivatives as Dopants
Authors: Takeoka Shinji , Hara Tomitarô , Yamamoto Kimihisa , Tsuchida Eishun
Published: March 2006

Thermal stability of electric conductivity of polypyrrole (PPy) was improved using aromatic sulfonate derivatives as dopants having mobile hydrogen in the form of acid groups such as sulfonic acid, carboxylic acid, or hydroxide groups. Particularly, when m-sulfobenzoic acid or 5-sulfosalicylic acid were used as dopants, the PPy showed high thermal stability of electric conductivity and kept 95% electric conductivity even after heating for 8 h at 150 °C in air.
New Cytotoxic Macrolides from the Sponge Fasciospongia rimosa
Authors: Tanaka Jun-ichi , Higa Tatsuo , Bernardinelli Gérald , Jefford Charles W
Published: March 2006

Two new cytotoxic macrolides, latrunculin S and neolaulimalide, have been isolated from the sponge Fasciospongia rimosa, and their structures determined by NMR and chemical correlation with known congeners.
A New Method for the Synthesis of Stannylenes: Exhaustive Desulfurization of Tetrathiastannolanes
Authors: Saito Masaichi , Tokitoh Norihiro , Okazaki Renji
Published: March 2006

Exhaustive desulfurization of overcrowded diaryl-substituted 1,2,3,4,5-tetrathiastannolanes having a 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (Tbt) group on the tin atom resulted in the formation of the corresponding kinetically stabilized diarylstannylenes, the formation of which was confirmed by the characteristic electronic absorptions attributable to the n-p transitions of stannylene, and by the chemical trapping by 2,3-dimethyl-1,3-butadiene.
Crystal Structure of [Ru(bpy)2(CO)(η1-C(O)OH)]+ (bpy = 2,2′-bipyridine) as a Key Intermediate in CO2/CO Conversion
Authors: Toyohara Kiyotsuna , Nagao Hirotaka , Adachi Tomohiro , Yoshida Toshikatsu , Tanaka Koji
Published: March 2006

Molecular structure of [Ru(bpy)2(CO)(η1-C(O)OH)](CF3SO3)(H2O) (bpy = 2,2′-bipyridine) has revealed that protonation of [Ru(η1-CO2)(bpy)2(CO)] as a key step in CO2/CO conversion shortens the Ru-C(O)OH bond distance compared with the Ru-CO2 one due to enhancement of dπ-pπ* interaction in the former.
A Significant Effect of a Lithium Salt in the Stereocontrolled Synthesis of α-d-Ribofuranosides
Authors: Uchiro Hiromi , Mukaiyama Teruaki
Published: March 2006

Lithium bis[(trifluoromethyl)sulfonyl]imide was found to be a new and effective additive in the stereocontrolled synthesis of α-d-ribofuranosides from 2,3,5-tri-O-benzyl-d-ribofuranose and several alcohols while β-anomers were formed in the absence of the lithium salt. A hypothetical mechanism of this reverse stereocontrol to yield α-d-ribofuranosides by the influence of the lithium salt is discussed.
Application of Molecular Simulation to Prediction of Solubility Parameter
Authors: Suga Yoshinori , Takahama Tomohiko
Published: March 2006

Molecular dynamics simulations are performed for six types of solvents to predict the solubility parameters. Investigation of the deciding factor in determining these values is also reported.
Evidence for the Coordination Number Change of Rare Earth Ions in Rare Earth Phosphate Glasses
Authors: Kanno Hitoshi , Akama Yoshifumi
Published: March 2006

Rare earth phosphate glasses of the composition Ln(PO3)3·KPO3 (Ln : rare earth ion) were prepared and their glass transition temperatures (Tg′s) were measured. From the Tg variation across the series, it is shown that the coordination number of rare earth ions changes, probably from nine to eight, in the middle of the series.
New Type of Photochromism in Thioxanthene-10,10-dioxide Derivatives Based on Their Photoresponsive Acidity Change
Authors: Miki Sadao , Ikeyama Yasuyuki , Fukunishi Koushi
Published: March 2006

3-Methoxycarbonyl-9-methyl-6-trans-phenylazo- and 3-cyano-9-methyl-6-trans-phenylazothioxanthene-10,10-dioxide were synthesized. They reveal a property as a carbon acid based on the proton dissociation at C(9)-H, and the dissociation constants are much larger in their trans-azo form than the cis form. Their conjugate bases possess absorption band at around 670 nm. Developing and bleaching of the color are linked with the trans-cis photoisomerization of the phenylazo group.
Potential of Mean Forces of Solutes in Water by Modified Solvent-accessible Surface Method
Authors: Fukunishi Yoshifumi , Suzuki Makoto
Published: March 2006

We propose an empirical method for evaluating the potential of mean force (p.m.f.) of solutes in water by modifying the solvent-accessible-surface (SAS) method described by Eisenberg et al. In addition to the SAS energy, the energy required to generate an excluded volume between adjacent solute molecules and the energy contribution due to coulomb interactions are accounted for in the proposed method. The proposed method was examined on the p.m.fs of methane-methane in water and successfully reproduced the p.m.fs. This method basically applicable to general molecular interactions, such as protein-protein interactions in water.
Efficient Lanthanide Catalysis in Aminoacyl-Transfer from the Bipyridine-Functionalized Amide-Substrate to Alcohols at Ambient Temperature
Authors: Araki Koji , Kajikawa Takeshi , Kawaguchi Satoshi
Published: March 2006

Lanthanide cations showed high catalytic activities in aminoacylation of alcohols by the amide-substrates having bipyridine as a metal chelation site at 30 °C (first-order rate constants were 10−4 s−1 range at Ce3+/substrate = 0.2), yielding corresponding amino acid esters almost quantitatively.
Ruthenium Catalyst Supported on CeO2 for Ammonia Synthesis
Authors: Niwa Yusuke , Aika Ken-ichi
Published: March 2006

Lanthanide oxides (Sm2O3, La2O3, especially CeO2) were more effective for ammonia synthesis when used as the support of ruthenium catalysts rather than when used as the dopant. The activity of Ru/lanthana was superior to other metal oxide-supported ones such as Ru/MgO. The activity, Ru dispersion, BET surface area, and the amount of hydrogen consumption of Ru/CeO2 were influenced remarkably by hydrogen treatment, suggesting the SMSI phenomena. Partially reduced CeO2 donates electrons to Ru atoms, forming the active sites.
Saccharide Control of Energy-transfer Luminescence of Lanthanide Ions Encapsulated in Calix[4]arenes: A Novel Discrimination Method for the Energy-transfer Route
Authors: Matsumoto Hitoshi , Ori Aiichiro , Inokuchi Fumiaki , Shinkai Seiji
Published: March 2006

A calix[4]arene bearing three amide groups (composing a lanthanide binding site) and one sensitizer (phenacyl group) bearing an (o-boronylphenyl)methylaminomethyl group (acting as a sugar-binding site) was synthesized. The energy-transfer to Eu3+ was significantly enhanced whereas that to Tb3+ was only slightly enhanced, indicating that in the Eu3+ complex the energy is mainly transferred from the sensitizer whereas in the Tb3+ complex it is mainly transferred from the calix[4]arene aromatic rings. This is a novel method for discriminating the energy-transfer path.
NO Decomposition in the Presence of Excess O2 Using the Electrochemical Cells with Pd Electrodes Treated at High Temperature and Coated with La1−x Srx CoO3
Authors: Nakatani Jiro , Ozeki Yuji , Sakamoto Kousuke , Iwayama Kazuyoshi
Published: March 2006

Decomposition of NO in the presence of oxygen was promoted by using an electrochemical cell composed of YSZ and non-porous Pd electrodes. The NO conversion into N2 was successfully improved by coating the Pd electrodes with a perovskite oxide (La1−xSrxCoO3).
Photochemical Switching of Ferroelectric Liquid Crystals Using a Photoswitchable Chiral Dopant
Authors: Negishi Makoto , Tsutsumi Osamu , Ikeda Tomiki , Hiyama Tamejiro , Kawamura Joji , Aizawa Masao , Takehara Sadao
Published: March 2006

Fast optical switching (response time 90 μs) was achieved of ferroelectric liquid crystals doped with a photoresponsive chiral dopant having an azobenzene moiety.
Voltammetry with an Electrode Surface Successively Renewed by Laser-Ablation
Authors: Hinoue Teruo , Watanabe Iwao , Watarai Hitoshi
Published: March 2006

Voltammetric measurement was performed with a solid electrode surface which was renewed every several seconds by laser-ablation. The voltammograms obtained were, in appearance, quite similar to polarograms obtained with a dropping mercury electrode (DME). Oxidation waves of [Fe(CN)6]4− and l-ascorbic acid were examined by this voltammetry.
Formation of Silicone Coated Vesicle by Sol-Gel Method. TEM Observation
Authors: Ishiwatari Tsutomu , Shimizu Ikuo , Mitsuishi Masaru
Published: March 2006

The silane entrapped by a vesicle was polymerized by a base catalyst. A silicone membrane was formed around the vesicle. Most of the vesicular structure was maintained in the process. The vesicles coated by silicone were apt to aggregate with each other via the adhesion character of silicone.
Solvent-Free Benzylations of 2-Pyridone. Regiospecific N- or C-Alkylation
Authors: Almena Inés , Díaz-Ortiz Angel , Díez-Barra Enrique , Hoz Antonio de la , Loupy André
Published: March 2006

Regiospecific N- or C-benzylations of 2-pyridone are observed in solvent-free conditions in the absence of base. The regioselectivity is controlled by the heating technique (microwave irradiation or conventional heating) or, using microwaves, by the emitted power or the leaving group of benzyl halides.
A New Non-enzymatic Route to Chenodeoxycholic Acid
Authors: Bortolini Olga , Cova Umberto , Fantin Giancarlo , Medici Alessandro
Published: March 2006

A novel route for the production of the chenodeoxycholic acid is described, based on the selective non-enzymatic reduction of dehydrocholic acid The relative reactivity scale was established to be in the order: 12-keto (1), 7-keto (2), 3-keto (17.5).
Asymmetric Hydroesterification of Norbornene by Chiral Non-chelate Biphosphine Palladium Complexes
Authors: Zhou Hongying , Lu Shijie , Hou Jingguo , Chen Jing , Fu Hongxiang , Wang Hanqing
Published: March 2006

Asymmetric induction up to 92.2% has been obtained in the hydroesterification of norbornene with carbon monoxide and alcohols in the presence of Pd(OAc)2, 1,4:3,6-dianhydro-2,5-dideoxy-2,5-bis(diphenylphosphino)-l-iditol and p-toluenesulfonic acid.
Enantioselective Addition of Diethylzinc to Aldehydes Using 1,1′-Bi-2-naphthol-3,3′-dicarboxamide as a Chiral Auxiliary
Authors: Kitajima Hiroshi , Ito Katsuji , Katsuki Tsutomu
Published: March 2006

A highly enantioselective addition of diethylzinc to a wide range of aldehydes was achieved by using N,N,N′,N′-tetraalkyl-1,1′-bi-2-naphthol-3,3′-dicarboxamides as chiral auxiliaries.
Observation of a Novel Fluorescent Dimer of Zinc Tetrasulphonatophthalocyanine
Authors: Kaneko Yuji , Arai Tatsuo , Tokumaru Katsumi , Matsunaga Daisaku , Sakuragi Hirochika
Published: March 2006

Zinc(II) tetrasulphonatophthalocyanine (ZnPcS4−) exhibited a new absorption band (λmax 699 nm) at the longer wavelength side of the monomer absorption band in 1:49 aqueous acetonitrile. Irradiation of the new band exerted an emission (690–730 nm, λmax 710 nm) different from the monomer fluorescence.The new absorption and emission were ascribed to a novel type of ZnPcS4− dimer.
Relaxation of pBR322 Form I DNA by Copper(II) Complex and Hydrogen Peroxide
Authors: Kobayashi Teruyuki , Ito Sayo , Hamazaki Hiroshi , Ohba Shigeru , Nishida Yuzo
Published: March 2006

Relaxation of pBR322 form I DNA by copper(II) complex and hydrogen peroxide systems was found to be highly dependent on the chelate structure of copper(II) complex used. This is suggesting that an active species for nicking DNA may be a copper(II)-hydroperoxide adduct.
Solvatochromic Properties of an Ammonium Containing Polysilane in Water-Ethanol Binary Mixtures
Authors: Seki Takahiro , Tohnai Atsushi , Tamaki Takashi , Kaito Akira
Published: March 2006

A water-soluble polysilane having a trimethylammonium group has been synthesized and its spectroscopic properties in water, ethanol and their binary mixtures are investigated. In water-ethanol binary mixtures, variations in the UV absorption and fluorescence properties attributed to the delocalized σ electron in the Si backbone exhibit a maximum at intermediate mixing ratios.
Conformational Polymorphism of Mechanochromic 5,6-Di(p-chlorobenzoyl)-1,3,4,7-tetraphenylbenzo[c]thiophene
Authors: Mataka Shuntaro , Moriyama Hideki , Sawada Tsuyoshi , Takahashi Kazufumi , Sakashita Hirofumi , Tashiro Masashi
Published: March 2006

X-Ray crystallographic analyses show that mechanochromic polymorphs of 5,6-di(p-chlorobenzoyl)-1,3,4,7-tetraphenylbenzo[c]thiophene originate from different syn- and anti-arrangements of two vicinal carbonyl groups.
Emission Spectrum of NeAr2+ Cluster Ion Produced in the Flowing Afterglow
Authors: Tsuji Masaharu , Tanaka Makoto , Nakamura Masafumi , Nishimura Yukio
Published: March 2006

NeAr+ emission systems resulting from the three-body Ne+/2Ar and Ne+/Ar/He reactions were observed in the He flowing afterglow. At high Ar stagnation pressures above ∼1 atm, a new broad band appeared in the 210-275 nm region. It was ascribed to the bound-free C2-X, B-X, C1-A1, C2-A2, and B-A2 transitions of the NeAr2+ cluster ion.
Selective Permeation of Cadmium(II) Chloride Complex through Cellulose Triacetate Plasticizer Membrane Containing Trioctylmethylammonium Chloride Carrier
Authors: Hayashita Takashi , Kumazawa Mitsuaki , Yamamoto Megumi
Published: March 2006

A novel polymeric plasticizer membrane which is composed of cellulose triacetate as a membrane support, o-nitrophenyloctyl ether as a membrane plasticizer, and trioctylmethylammonium chloride as an anion-exchange carrier has been developed. Highly selective permeation of Cd(II) chloride complex through the plasticizer membrane was found to be obtained by the addition of EDTA in the receiving phase.
A Convenient Synthesis of Alkynylsilanes by Silylation of Copper(I) Alkynides
Authors: Sugita Hikaru , Hatanaka Yasuo , Hiyama Tamejiro
Published: March 2006

Alkynylation of chlorosilanes with copper(I) alkynides takes place smoothly in the presence of triphenylphosphine, N, N, N′, N′-tetramethylethylenediamine, or zinc powder to give a variety of alkynylsilanes in good yields.
Optical Resolution of Chiral Ethylenebis(4,5,6,7-tetrahydro-1-indenyl)zirconium Derivatives by High-Performance Liquid Chromatography
Authors: Habaue Shigeki , Sakamoto Hiroshi , Okamoto Yoshio
Published: March 2006

Optical resolution of racemic C2-symmetric ethylenebis(4,5,6,7-tetrahydro-1-indenyl)zirconium derivatives was accomplished by high-performance liquid chromatography using cellulose tris(3,5-dimethylphenylcarbamate) as a chiral stationary phase.
Exploitation of Na+-Selective Electrodes for Protein Solutions from Crown-Bridged Calix[4]quinones
Authors: Yamamoto Hiromasa , Ueda Keiko , Suenaga Hikaru , Sakaki Toru , Shinkai Seiji
Published: March 2006

Crown-bridged calix[4]quinones (5 and 6) were synthesized from calix[4]crown (2). The ion-selective electrodes prepared from 5 or 6 still retained high selectivity for Na+ against K+ (>103). For protein solution samples the electrode prepared from 2 showed a large phase divergence whereas those prepared from 5 or 6 were much more stable in protein solution. The difference is attributed to the less hydrophobic nature of 5 and 6 which strongly influences the protein adsorption onto the membrane surface.
A Monomeric Zinc Complex Ligated by an Unsymmetric Hydrotris(pyrazolyl)borate Containing an OH Group
Authors: Osawa Masahisa , Tanaka Masako , Fujisawa Kiyoshi , Kitajima Nobumasa , Moro-oka Yoshihiko
Published: March 2006

A novel zinc complex having an unsymmetric tris(pyrazolyl)borate, Zn(OAc)[HB(3-Me2C(OH)-5-iPrpz)(3,5-iPr2pz)2], was synthesized by the transmetalation of an oxygenated product formed a dimanganese(II, II) complex {Mn[HB(3,5-iPr2pz)3]}2(OH)2 with molecular oxygen.
Diffusionless Electrochemistry of Cytochrome b5 Adsorbed on a Multilayer Film Electrode
Authors: Glenn Julie D H , Bowden Edmond F
Published: March 2006

A multilayer film electrode has been developed that is well-suited for diffusionless electron transfer studies of acidic proteins. The multilayer electrode is comprised of trypsin-solubilized cytochrome b5 adsorbed electrostatically to a self-assembled HO2C(CH2)7SH/gold substrate via an intervening bridging layer of cationic poly-l-lysine.
Two-dimensional Molecular Patterning through Molecular Recognition
Authors: Oishi Yushi , Torii Yuzuru , Kuramori Miyuki , Suehiro Kazuaki , Ariga Katsuhiko , Taguchi Kazuhiro , Kamino Ayumi , Kunitake Toyoki
Published: March 2006

Molecular images for the mixed monolayers composed of guanidinium (G) and orotate (O) amphiphiles on pure water and on aqueous flavin adenine dinucleotide (FAD) solution were taken with an atomic force microscope (AFM). The AFM image of G/O mixed monolayer on FAD showed a periodic pattern composed of two kinds of peaks with different heights, whereas that on pure water showed a periodic peak. The molecular pattern is apparently induced by rearrangement of monolayer components based on specific recognition by FAD template molecule.
The Influence of the Chirality of Synthetic Iron Chelators Bearing N-Hydroxy-2(1H)-pyrazinones and Amino Acid Residues upon Iron Removal from Human Transferrin
Authors: Ohkanda Junko , Katoh Akira
Published: March 2006

New chiral iron chelators bearing N-hydroxy-2(1H)-pyrazinone, d-amino acid residues, and tris(2-aminoethyl)amine were synthesized, and their kinetic behavior of iron removal from human transferrin was investigated. The rate of iron removal by the chelator bearing d-alanine residue was suppressed to only one fourth that of l-alanine derivative.
Effects of Substituents on the Indoline Ring on the Negative Photochromic Properties of Spirobenzopyran Derivatives
Authors: Minami Masato , Taguchi Nobuyoshi
Published: March 2006

Novel substituted -6,8-dinitro-l′,3′,3′-trimethylspiro[2H-1-benzopyran-2,2′-indoline] derivatives have been synthesized in high yields, and their properties are investigated. The absorption maxima of the ring-open forms and the negative photochromic properties of spirobenzopyrans significantly depend on the substituents in the indoline ring and on the nature of the solvent used.
Crystal Structure of Dl-12-Hydroxystearic Acid
Authors: Kuwahara Tetsuro , Nagase Hiromasa , Endo Tomohiro , Ueda Haruhisa , Nakagaki Masayuki
Published: March 2006

12-Hydroxystearic acid was stacked to give a lamellar structure. 12-Hydroxy groups formed hydrogen bond sequences along the a-axis. The hydrocarbon chains took approximately an all-trans conformation, but might be slightly bent because of the 12-hydroxy group.
NMR Study of Pressure Effect on the Hindered Rotation in cis-1,12-Disubstituted[12]paracyclophanes
Authors: Yamada Hiroaki , Mukuno Kuniko , Umeda Mami , Maeda Takayasu , Sera Akira
Published: March 2006

Effect of hydrostatic pressure on the rate of internal rotation of title compounds has been examined by DNMR method. A quartz high–pressure NMR cell was used to realize the high–pressure experiment up to 300 MPa. The rate of internal rotation, lnk was found to increase linearly up to 300 MPa.
Crystal and Molecular Structure of 1,2-Dimethoxyethane Crystallized on a New Diffractometer
Authors: Yokoyama Yoshihiro , Uekusa Hidehiro , Ohashi Yuji
Published: March 2006

Crystal and molecular structure of 1,2-dimethoxyethane (DME) with low melting point (−58 °C) was investigated by crystallization on a new imaging plate-Weissenberg type diffractometer with a new low temperature equipment. The crystal belongs to the monoclinic system and the space group is C2/c. There are four molecules in a unit cell. The DME molecule lies on a two-fold axis and has a TGT conformation in the crystalline state.
Synthesis of Symmetric Oligo-DNA Dimers and Their Formation of Polymeric Supramolecular Assembly
Authors: Ohya Yuichi , Noro Hiroshi , Komatsu Mamoru , Ouchi Tatsuro
Published: March 2006

p-Hydroxybenzene was coupled with tetrathymidine or tetraadenosine through phosphodiester bonds to give symmetric oligo-DNA dimers, (T4)2Bz and (A4)2Bz, as components for a polymeric supramolecular assembly. The equivalent mixture of them formed a high-molecular-weight aggregate in aqueous media via complemental hydrogen bonds.
Ceric Ammonium Nitrate Mediated Cycloaddition of Hydroxyquinones with Alkenes for the One-Step Construction of Furoquinone Derivatives
Authors: Kobayashi Kazuhiro , Mori Masako , Uneda Tomokazu , Morikawa Osamu , Konishi Hisatoshi
Published: March 2006

A one-step formation of furoquinones, such as naphtho[2,3-b]furan-4,9-dione, naphtho[1,2-b]furan-4,5-dione, benzofuran-4,7-dione, and benzofuran-4,5-dione derivatives, by the ceric ammonium nitrate mediated [3+2] type cycloaddition of 2-hydroxy-1,4-naphthoquinones and 2-hydroxy-1,4-benzoquinones with alkenes or phenylacetylene is described.
Extractions of Ca@C60 and Sr@C60 with Aniline
Authors: Kubozono Yoshihiro , Noto Takako , Ohta Takayoshi , Maeda Hironobu , Kashino Setsuo , Emura Shuichi , Ukita Shigeyuki , Sogabe Toshiaki
Published: March 2006

Endohedral metallofullerenes, Ca@C60 and Sr@C60, prepared by the arc-heating of the graphite rods containing CaO and SrO, respectively, have been extracted with aniline under the air atmosphere. The laser desorption time-of-flight (LD-TOF) mass spectra for the extracted solutions exhibit intense peaks due to M@C60+ (M: Ca and Sr) and C60+ with weak peaks due to the other hallow fullerenes and metallofullerenes.
Temperature Dependence of Chiral Recognition in the Oxidation of Tris(ethylene-diamine)cobalt(II) Complex by Optically Active Anionic Cobalt(III) Complexes
Authors: Tatehata Akira , Muraida Akira
Published: March 2006

The temperature dependence of the stereoselectivity in the oxidation of tris(ethylenediamine)cobalt(II) complex by some chiral anionic cobalt(III) complexes has been studied over the temperature range of 5-45°C in aqueous solution. The activation enthalpy difference, ΔΔH‡, and the entropy difference, ΔΔS‡, between Δ-Λ and Δ-Δ pairs show two kinds of ΔΔH‡/ΔΔS‡ compensation behavior, indicating that the electron-transfer proceeds by two different types of reaction mechanisms. The relative importance of ΔΔH‡ and ΔΔS‡ is interpreted in terms of the difference in the stereoselective interactions upon formation of the precursor complex.
Synchronous Current Oscillations in Electrochemical Reduction Reactions on Two Platinum Electrodes in Sulfuric Acid Solution Containing Hydrogen Peroxide
Authors: Mukouyama Yoshiharu , Hommura Hayato , Matsuda Toshihiko , Yae Shinji , Nakato Yoshihiro
Published: March 2006

Synchronous oscillations are found for reduction currents on two independently potential–controlled Pt electrodes in 0.7 M H2O2–0.3 M H2SO4. It is shown that electrical interaction between the two oscillating electrochemical systems through the electrolyte solution is responsible for the synchronization.
Structure Disordering during Surface Pressure Relaxation of Langmuir Films of Stearic Acid as Studied by Infrared External Reflection Spectroscopy
Authors: Sakai Hiroshi , Umemura Junzo
Published: March 2006

In situ FT-IR external reflection spectra of Langmuir films of stearic acid on the water surface were recorded duing the surface pressure relaxation at two surface areas, corresponding to the liquid condensed (L2) and super-liquid (LS) phases. In the L2 phase, the surface pressure relaxation was minimal and so was the spectral change. In the LS phase, however, the structural change from the trans to gauche conformation was detected.
Complexation Kinetics of 5-Octyloxymethyl-8-quinolinol with Ni(II) at the Heptane-Water Interface
Authors: Shioya Takeshi , Tsukahara Satoshi , Teramae Norio
Published: March 2006

Complexation kinetics of 5-octyloxymethyl-8-quinolinol (Hocqn) with Ni(II) at the heptane-water interface was studied by measuring the dynamic interfacial tension. Decrease in the interfacial tension was caused by the adsorption of 1:1 complex formed at the interface. It was found that the complexation rate at the interface was 43 times faster than that in the bulk, and that the rate also depended on the counter-anion in the aqueous phase.
syn-trans Fused Bicyclic Ether Formation via Acetylene-biscobalthexacarbonyl Complex
Authors: Isobe Minoru , Hosokawa Seijiro , Kira Kazunobu
Published: March 2006

Medium size bicyclic ethers of 7-, 8-, and 9-membered rings were synthesized by connection between a hydroxy group on dihydropyranyl ring and a propargylic cation that was stabilized as an acetylene biscobalthexacarbonyl complex under acidic conditions. This cyclization selectively afforded the syn-trans bicyclic ring system often seen in marine toxins such as ciguatoxin.
Direct Observation of Solutes Trapping on a Surface-inert Reversed Phase Column
Authors: Tamura Atsushi , Khademizadeh Maasoomeh , Razee Saeid , Masujima Tsutomu
Published: March 2006

The solute trapping process onto the surface-inert reversed phase packing was dirctly investigated with chromato-videoscope. The Fluorescence intensity of separating dansyl (DNS) amino acids in the column was detected by video camera and densitogarm of solutes along the column length was obtained with computer-processing of the video images. Band widths of trapped DNS amino acids were narrow in the absence of BSA in sample solution. However, in the presence of BSA, band shapes turned broad according to increase of the concentration of BSA or injected volume of the sample.
Cyclic Voltammetry of Cucumber Ascorbate Oxidase
Authors: Sakurai Takeshi
Published: March 2006

Direct electrochemistry of cucumber ascorbate oxidase at Au electrodes modified with various promoters gave redox waves originating from the type 1 copper.
An Asymmetric Synthesis of the BC Ring System of 8-Epitaxoids by Way of Intramolecular Aldol and Successive Stereoselective Methylation Reactions
Authors: Mukaiyama Teruaki , Shiina Isamu , Iwadare Hayato , Saitoh Masahiro , Nishimura Koji , Nishimura Toshihiro , Ohkawa Naoto , Sakoh Hiroki , Saitoh Katsuyuki
Published: March 2006

Optically active 1α-allyl-1β,11β-benzylidenedioxy-2α,10β-bis(benzyloxy)-7β,9β-isopropylidenedioxy-8α,12,12-trimethyl-4-methylenebicyclo[6.4.0]dodecane (2)1 which corresponds to BC ring system of 8-epitaxoids was prepared in high yield form ketoaldehyde 8  via intramolecular aldol cyclization and succesive stereoselective methylation reactions. The ketoaldehyde 8 was synthesized from 8-membered ring compound 3 by stereoselective Michael addition using higher-order cuprate.
Stereoselective Synthesis of ABC-Ring System of Hemibrevetoxin B
Authors: Matsukura Hiroko , Morimoto Masamichi , Nakata Tadashi
Published: March 2006

The 6, 6, 7-membered tricyclic ether ring system (ABC-ring) of hemibrevetoxin B was stereoselectively synthesized. The curcial steps in the present synthesis involve the ring expansion of tetrahydropyran to oxepane, 6-endo cyclization of epoxy alcohol, and insertion of a C-4 unit to the A-ring.
Crystal Structure of a Tris(dithiolene) Vanadium(IV) Complex Having Unprecedented D3h Symmetry
Authors: Kondo Mitsuru , Minakoshi Seika , Iwata Kazuko , Shimizu Toshio , Matsuzaka Hiroyuki , Kamigata Nobumasa , Kitagawa Susumu
Published: March 2006

The crystal structure of a tris(dithiolene)vanadium(IV) complex, [V(S2C2H2)3] (1), was determined. This complex shows the first instance of the nearly perfect D3h geometry in tris(dithiolene) vanadium(IV) complexes. In comparison with 1, the crystal structures of (NEt4)2[V(bdt)3] (bdt2− = 1,2-benzenedithiolate) (2) and (NEt4)2[V(tdt)3] (tdt2− = 3,4-toluenedithiolate) (3) having distorted Oh geometries were also determined by X-ray crystallography.
Solubilization of Meso-Carbon Materials by Butylation with Dibutylzinc and Butyl Iodide
Authors: Zhang Yan , Kidena Koh , Murata Satoru , Nomura Masakatsu , Yoneyama Yoshiharu , Kato Tsutomu
Published: March 2006

Solubilization of meso-carbon microbeads (MCMB) with dibutylzinc-butyl iodide reagents was investigated, this reaction giving tetrahydrofuran-soluble materials in 94-97% yeild. This is the first example, to our knowledge, for effective solubilization of these meso-carbon materials. The Mode of introduction of butyl groups was also clarified by using 13C-NMR of butylated samples.
Preparation of a Polymer with Limited π-Conjugation Length: A Polymer Containing Quaterthiophene Units
Authors: Sato Masa-aki , Hiroi Masao
Published: March 2006

A polymer containing quaterthiophene units in the main chain was prepared by electrochemical polymerization of 1,2-bis(3′-hexyl-2,2′-bithiophene-5-yl)ethane. The obtained green film had a conductivity of 2 × 10−2 S cm−1 in oxidized states and was neutralized by immersing in methanol. The cyclic voltammograms of the neutral film showed only an oxidation process in the first cycle.
A Facile Preparation and Polymerization of 1,1-Difunctionalized Disiloxanes
Authors: Mori Atsunori , Sato Hiroyoshi , Mizuno Katsuya , Hiyama Tamejiro , Shintani Koji , Kawakami Yusuke
Published: March 2006

Novel 1,1-difunctionalized disiloxanes are synthesized by the alkylative cleavage of cyclic siloxane using several alkyllithiums followed by quenching with chlorosilanes. The prepared difunctionalized siloxanes are subjected to polyaddition through platinum catalyzed hydrosilylation.
Thermal Study of a Silylmethylated Fullerene Leading to Preparation of Its Vacuum Deposited Thin Films
Authors: Nagashima Hideo , Kato Yoshiyuki , Satoh Hirohisa , Kamegashima Naoki , Itoh Kenji , Oi Kazuhiro , Saito Yahachi
Published: March 2006

Thermal study of a C60 derivative containing a siloxane structure revealed that it was unstable above 350 °C. A major decomposition pathway was formation of C60 and (Me3Si)2O presumably via homolysis of bonds between the α-carbon of the silyl group and the cage carbon. By careful control of the crucible temperature below 350 °C, amorphous vapor-deposited thin films on NaCl or mica were successfully prepared.
Decorative Coatings of Plating with Antibacterial Activity
Authors: Zhi-hong Zhao , Eguchi Seiichiro , Okada Yoshio , Osaka Tetsuya
Published: March 2006

Electroplated coatings of cobalt, zinc, copper and cobalt-containing alloys of nickel, zinc and chromium were found to have bactericidal action. The electroless plated coating of silver also hindered against proliferate of bacteria. Especially, they have bactericide properties to methicillin-resistant strains of Staphylococcus aureus (MRSA) in all. In addition, we discussed the relationship between rest potentials of various electroplated coatings and bactercidal action.
Molecular Structure of Inclusion Complex with Chloride Anion Eccentrically Bound into the Cavity of a Tetraazamacrotricyclic Receptor Having Asymmetrically Charged Nitrogen Centers
Authors: Hossain Md Alamgir , Ichikawa Kazuhiko
Published: March 2006

The crystal structure of [ClL]2+·2Cl−·3CH3OH, where L = (C6H5CH2)3N4((CH2)6)6, shows the complete encapsulation of a chloride anion into the intramolecular cavity of the macrotricyclic cage L3+. The included anion is held eccentrically into the cavity with a distance of about 4.1 Å from the three charged nitrogen cations and 5.7 Å from the uncharged nitrogen atom.
Synthesis, Structure, and Electrochemistry of a Dodecanuclear Chromium Cluster Complex [Cr12S16(PEt3)10]
Authors: Kamiguchi Satoshi , Imoto Hideo , Saito Taro
Published: March 2006

A dodecanuclear chromium sulfide cluster complex [Cr12S16(PEt3)10] has been synthesized by the reaction of a hexanuclear cluster complex [Cr6S8(PEt3)6] with sulfur. This complex has two octahedral Cr6S8 cores that are linked by two Cr-S bonds. The intercluster bonding mode is similar to that in the Chevrel phases. Cyclic voltammetry shows the existence of the intercluster electronic interaction between the two Cr6S8 cluster units.
Dynamic Photochemical Response of Ruthenium (II)/(III) Redox Chemical Waves in Belousov-Zhabotinsky Reaction
Authors: Akagi Toshimasa , Matsumura-Inoue Takeko
Published: March 2006

The dynamic photochemical response of Ru(bpy)32+-catalyzed Belousov-Zhabotinsky (B-Z) reaction was studied in a thin layer solution system with a mask. It was found that stable chemical waves are generated from a masked area and their features are dependent on the chemical components. A high [MA]0 greatly contributes to the photosensitivity of the system. (MA = CH2(COOH)2)
Electrochemical Behavior Hetero-Deposited Redox Polymer Langmuir-Blodgett Films with Ferrocene and Tris(bipyridine)ruthenium Derivatives
Authors: Aoki Atsushi , Miyashita Tokuji
Published: March 2006

Stable redox polymer monolayer and Langmuir-Blodgett (LB) films can be prepared from amphiphilic copolymers of N-dodecylacrylamide (DDA) with ferrocene derivative (Fc) and with ruthenium complex (Ru). Electrochemical properties of the LB films fabricated from the hetero-deposition of Ru and Fc copolymer monolayers onto ITO electrodes were investigated using cyclic voltammetry. The results demonstrate that the hetero-deposited redox polymer LB films show rectifying property and charge storage.
Enhancing Effect of Titanium(II) for the Oxidation of Methane with O2 by an EuCl3-Zn-CF3CO2H-Catalytic System at 40 °C
Authors: Yamanaka Ichiro , Soma Masanori , Otsuka Kiyoshi
Published: March 2006

Bis(2,4,-pentanedionate)TiO and TiO2 enhanced markedly the activity of the EuCl3-Zn0-CF3CO2H-catalytic system for the CH4 oxidation to MeOH with O2 at 40 °C. It is suggested that Ti(II) species generated from Ti(IV) by the reduction with Zn0 and CF3CO2H is responsible for this enhancement.
A Novel Preparation of Thiogallate-based Rare-earth Phosphors
Authors: Kobayashi Takeshi , Uheda Kyota , Naruke Haruo , Yamase Toshihiro
Published: March 2006

EuGa2S4 and CaGa2S4:Ce were prepared by a method of the decomposition of metal dimethyldithiocarbamates which provides a simple and safe technique desired for the phosphor production. UV-irradiation of such EuGa2S4 and CaGa2S4:Ce (in the Ce / Ca = 1 / 20 ratio) polycrystallines gave green and blue emission with high yield, as exemplified by relative yields of 0.17 and 0.84 against a commercially available Y2SiO5:Ce blue phosphor at room temperature respectively.
Synthesis and Characterization of a Binuclear Porphyrin Complex as a Model for Heme a3-CuB Site of Cytochrome c Oxidase
Authors: Fujii Hiroshi , Yoshimura Tetsuhiko , Kamada Hitoshi
Published: March 2006

A binuclear complex, 1, involving copper and heme complexes is synthesized and characterized by paramagnetic 1H-NMR, FAB mass, and ESR spectroscopies. These measurements indicate a fairly weak magnetic interaction between iron and copper ions when a bridege ligand is absent.
Electrocatalytic Hydrogenation of Acetylenes on Palladium Incorporating Poly [N-(5-Hydroxypentyl) Pyrrole] Film-Coated Electrode
Authors: Takano Nobuhiro , Kawakami Yutaka , Takeno Noboru
Published: March 2006

The catalytic polymer film electrode which was coated with poly[N-(5-hydroxypentyl) pyrrole] film on carbon materials and incorporated palladium metal microparticles in film was prepared. By use of the electrode the electrocatalytic hydrogenation of acetylenes in organic solvent-HCl buffer solution led to the efficient formation of ethanes in high current efficiencies.
Al3+-Exchanged Montmorillonite as an Effective Solid Catalyst for Selective Synthesis of Alkylphenols and Bisphenols
Authors: Tateiwa Jun-ichi , Hayama Ei , Nishimura Takahiro , Uemura Sakae
Published: March 2006

Al3+-Exchanged montmorillonite-catalyzed aromatic alkylation of phenol with aldehydes produces the corresponding bisphenols mainly or almost solely in good yields, while that with ketones affords selectively the corresponding alkylphenols in moderate to good yields, the alkylation always occurring at the carbonyl carbon.
Strong Magnetocrystalline Anisotropy in MnTPP-TCNE Charge Transfer Complex
Authors: Nagai Keiji , Iyoda Tomokazu , Fujishima Akira , Hashimoto Kazuhito
Published: March 2006

Magnetic properties of one-dimensional charge transfer complex between manganese meso-tetraphenylporphyrin (MnTPP) and tetracyanoethylene (TCNE) were investigated as its plate crystals. Strong magnetocrystalline anisotropy was observed in the field and the temperature dependences of magnetization. Magnetic phase transition was observed as 24 K and 27 K under 0.5 T of magnetic field along a- and b-axes, and c-axis, respectively. Either temperature was higher than that (18 K) of powder sample reported previously.
Mono-, Di-, and Trimetallic Palladium(II) Porphyrin Trimers with Etheno-bridges
Authors: Higuchi Hiroyuki , Takeuchi Makoto , Ojima Juro
Published: March 2006

Mono-, di-, and trimetallic Pd(II) complexes of the etheno-bridge porphyrin trimer 1 were prepared. It was found that the metalation of 1 first occurred in the inner porphyrin ring. The trimetallic Pd(II) trimer 6 exibited splitting of the Soret band and complete disappearance of the weak bands ranging from 600 to 1000 nm unlike the corresponding free-base and Ni(II) porphyrin trimers.
Reaction and Stereochemistry of C-Glycosidation in 2-Deoxy-4-Thioribofuranoside
Authors: Uenishi Jun’ichi , Sohma Atsushi , Yonemitsu Osamu
Published: March 2006

SnCl4 mediated C-glycosidation reactions of ethyl 2-deoxy-4-thioribofuranoside with silylated nucleophiles were described. α-Anomer was the major product formed in the reactions. The stereochemical course was found to be similar to that of ethyl 2-deoxyribofuranoside.
Two Kinds of Intermolecular π-π Interactions Controlling the Crystalline State Structure of 12,13,25,26-Tetraaza-2,15-dithia[3.3]phenanthrolinophane
Authors: Wang Zhen-He , Hirose Takuji , Hiratani Kazuhisa , Yang Yanyan , Kasuga Kazuyuki
Published: March 2006

The structural characterization of a dithiaphenanthrolinophane was performed. The stable structure in the crystalline state was found to be different from that in solution. The intermolecular face-to-face and edge-to-face π-π interactions of the aromatic rings play important roles in stabilization of the crystalline state conformation.
All-Solid State Electric Double Layer Capacitor Using Polymer Electrolyte and Isotropic High Density Graphite Electrodes
Authors: Liu Xingjiang , Momma Toshiyuki , Osaka Tetsuya
Published: March 2006

Isotropic high density graphite (HDG) was used as the polarizable electrode of electric double layer capacitors (EDLC) with a solid electrolyte consisting of PEO/LiClO4([EO]/[Li+] = 8:1) at 80 °C or with a gel electrolyte consisting of PEO/PC/LiClO4([EO]/[PC]/[Li+] = 8:8:1) at room temperature. The all-solid state capacitor with HDG electrodes works satisfactorily as a EDLC with a relatively high capacitance, as well as the EDLC with gel electrolyte PEO/PC/LiClO4. These EDLCs with solid polymer electrolyte PEO/LiClO4 and gel electrolyte PEO/PC/LiClO4 show good charge/discharge behavior when charged to 1.5 V at 80 °C and 20 °C, respectively.
Reduction of α-Halo Carbonyl Compounds with NaBH4-SbBr3
Authors: Sayama Shinsei , Inamura Yutaka
Published: March 2006

The reagent NaBH4-SbBr3 was found to be chemoselective for the reductive debromination of aromatic α-bromo carbonyl compounds and 2,3-dibromo-1,4-butanediones.
Conformational Stability of 1,2-Dimethoxyethane in the Gas Phase Studied by Infrared Spectroscopy: Importance of an Intramolecular 1,5-CH···O Interaction
Authors: Yoshida Hiroshi , Tanaka Takeshi , Matsuura Hiroatsu
Published: March 2006

The gas-phase infrared spectra of 1,2-dimethoxyethane measured at various temperatures gave a value of 0.31 ± 0.04 kcal mol−1 for the energy difference between the trans–gauche–gauche′ and trans–trans–trans conformers, the latter being more stable. This value is in good agreement with the results of high-level ab initio calculations. The present experimental finding gives definitive evidence for the importance of an intramolecular 1,5-CH···O interaction in the stabilization of the trans–gauche–gauche′ conformer in the gas phase.
Aggregation of Synthetic Zinc Complexes of Cyclotetrapyrroles
Authors: Tamiaki Hitoshi , Kubota Takayuki , Tanikaga Rikuhei
Published: March 2006

Zinc complexes of cyclotetrapyrroles possessing 31-hydroxyl and 131-keto carbonyl groups were prepared. The electronic and circular dichroism absorption spectra showed that these compounds self-aggregated in less polar organic solvents to form oligomers, which are good models for natural aggregates of bacteriochlorophyll-d in photosynthetic antennae.
Dinuclear Nickel(II) Complexes Containing a Dinucleating Ligand N,N,N′,N′-Tetrakis-[(1-ethyl-2-benzimidazolyl)methyl]-2-hydroxy-1,3-diaminopropane and an Acetate Ion
Authors: Nakao Yasuo , Mori Chikako , Mori Wasuke , Sakurai Takeshi , Matsumoto Keiji , Kimoto Hiroshi
Published: March 2006

The dinuclear nickel(II) complexes [Ni2(L1)(OAc)(MeOH)2](ClO4)2·H2O·MeOH 1 and [Ni2(L1)(OAc)(H2O)2](ClO4)2  2 (HL1 = N,N,N′,N′-tetrakis[(1-ethyl-2-benzimidazolyl)methyl]-2-hydroxy-1,3-diaminopropane) were prepared. The complex 1 turns to 2 upon exposure to the air. The crystal structure of 1 and the magnetic and spectroscopic properties of 2 were determined.
Preparation, Structure and Properties of Mixed-Metal Trinuclear Complex: (Pr4N)2[MoO(WS4)2]
Authors: Takai Kyoko , Umakoshi Keisuke , Sasaki Yoichi
Published: March 2006

A mixed-metal trinuclear complex, (Pr4N)2[MoO(WS4)2], has been prepared for the first time in pure form and characterized by several physical methods, including X-ray crystallography.
FT-IR Spectra of the Azide-Type 3 Copper in Laccase and Ascorbate Oxidase
Authors: Sakurai Takeshi , Takahashi Junya , Huang Hong-wei
Published: March 2006

The azide-treated laccase and ascorbate oxidase gave the asymmetric stretching bands (va) at 2056 and 2054 cm−1 in the FT-IR spectra, respectively.
Monolayers of Poly(ethylene oxide)-Bearing Lipids at Air-Water Interface
Authors: Rosilio Véronique , Albrecht Geneviéve , Baszkin Adam , Okumura Yukihisa , Sunamoto Junzo
Published: March 2006

Monolayers of poly(ethylene oxide)-bearing lipids and their mixed monolayers with dimyristoylphosphatidylcholine at the air-water interface was investigated using surface pressure measurements. The surface pressure-area relationship revealed that the poly(ethylene oxide) moiety length significantly affected the interaction among the lipid molecules. This study provided a precise picture of the lipid membrane-water interface.
Syntheses and Structure of New Dinuclear Palladium(II) Complexes with 1,1,2,2-Tetraacetylethanate and β-Diketonate
Authors: Kobayashi Yumiko , Nagao Noriharu , Okeya Seichi , Fukuda Yutaka
Published: March 2006

[Pd2(hfac)2(μ-MeO)2] (1) (hfac− = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate) reacts with 1,1,2,2-tetraacetylethanediide (H2taet) to give a dinuclear mixed ligand complex [Pd2(taet)(hfac)2] (2) having bridging taet2− ligand. The terminal hfac− ligands in the dinuclear complex [Pd2(taet)(hfac)2] (2) are replaced easily by acac− to obtain [Pd2(taet)(acac)2] (3) (acac− = 2,4-pentanedionate). The structures of the two complexes obtained were determined by X-ray analysis.
Preparation of a Stable Sulfonato-Cobalt(III) Complex by Oxidation of a Sulfinato-O Complex
Authors: Murata Mayumi , Kojima Masaaki , Kita Masakazu , Kashino Setsuo , Yoshikawa Yuzo
Published: March 2006

A stable sulfonato complex, [Co{OS(O)2CH2CH2NH2-O,N}(en)2]2+, was prepared upon oxidation of [Co{OS(O)CH2CH2NH2-O,N}(en)2]2+ in acid media. This sulfonato complex was resolved by SP-Sephadex column chromatography (eluent: 0.1 mol dm−3 Na2[Sb2{(+)-tartrate}2]). The absolute configuration of the slower eluted (−)589-isomer was determined to be Δ by the X-ray method.
Synthesis of Chiral Calix[4]resorcinarenes via Mono-O-henzylation. Complexation Behavior with a Chiral Trimethylammonium Compound
Authors: Konishi Hisatoshi , Tamura Takashi , Ohkubo Hiromichi , Kobayashi Kazuhiro , Morikawa Osamu
Published: March 2006

Chiral calix[4]resorcinarenes were prepared via mono-O-benzylation, and their conformational properties in solution were described. The complexation behavior of the heptahydroxy derivative with a chiral trimethylammonium compound in methanol was investigated by 1H NMR spectroscopy.
Cl2 Gas Detection at Low Temperature Using the 0.97PbCl2-0.03KCl Solid Electrolyte Prepared by the Melting Method
Authors: Aono Hiromichi , Yamabayashi Ayako , Sugimoto Eisuke , Mori Yoshiaki , Sadaoka Yashihiko
Published: March 2006

A Cl2 gas sensor with a 0.97PbCl2-0.03KCl solid electrolyte and a Pb reference electrode was prepared by a melting mehtod using an evacuated closed tube. The electromotive force (EMF) measured at 573 K agreed with the calculated value for Cl2 gas concentrations from 10 ppm to 1000 ppm. The response time was long when the operating temperature is lower than 473 K.
Selective Synthesis of Tungsten(VI) Mono(catecholato) Complexes Using 1,2-Bis(trimethylsiloxy)benzenes: Molecular Structure of WCl4(O2C6H4)
Authors: Nakayama Yuushou , Saito Hideo , Nakamura Akira
Published: March 2006

Reaction of tungsten hexachloride with 1,2-bis(trimethylsiloxy)benzenes (1) selectively gives mono(catecholato)tetrachlorotungsten(VI) complexes, WCl4(O2-1,2-C6H3R-4) (2a: R = H; 2b: R = Me; 2c: R = But). 1H NMR spectra of these complexes show significant upfield shifts of signals of aromatic protons. The distorted octahedral geometry of 2a was revealed by X-ray crystallography.
Oxidation and Thermolysis of a Stable Germaketenedithioacetal Derivative
Authors: Kishikawa Kuniyuki , Tokitoh Norihiro , Okazaki Renji
Published: March 2006

The reaction of germaketenedithioacetal 2 with oxygen gave 1,3,2-dithiagermetan-4-one 4 and dihydroxygermane 6, suggesting the initial formation of a 1,2,3-dioxagermetane intermediate 3 followed by its dissociation into 4 and germanone 5. Compound 2 underwent ready thermal dissociation into carbon disulfide and the corresponding germylene 1, the efficient formation of which was evidenced by a trapping experiment with 2,3,-dimethyl-1,3,-butadiene.