bluuebunny/crossref_metadata_2025 huggingface dataset:
Imine-Forming Radical Elimination Reactions of O-(1-Naphthoyl)-N,N-bis(p-substituted benzyl)hydroxylamines Activated by Triplet Benzophenone
Authors: Andoh Fumihiko , Kubo Kanji , Sakurai Tadamitsu
Published: May 2005

It was shown that despite the occurrence of a diffusion-limited triplet energy transfer between the title hydroxylamine 1 and benzophenone, triplet 1 decomposed inefficiently giving p-substituted N-(p-substituted benzylidene)benzylamine 2 and 1-naphthoic acid (3) as unimolecular radical elimination products. The logarithm of the kr/kd ratio (where kr is the rate constant for homolytic cleavage of the N–O bond in triplet 1 and kd is that for its deactivation) used as a measure of the triplet-state reactivities of 1, showed a negligible dependence on the substituent constant. This finding was explained in terms of a very small contribution of the ionic structure to the transition state for the N–O bond homolysis.
Decarbonylation Reaction of 1-Azulenecarbaldehydes under Mild Conditions. A Strategy for the Protection of 1- and/or 3-Position of Azulene Rings
Authors: Ito Shunji , Morita Noboru , Asao Toyonobu
Published: May 2005

The reaction of 1-azulenecarbaldehydes 9a and b with pyrrole (8) in acetic acid resulted in decarbonylation to afford azulenes even at room temperature in 49 and 78% yields, respectively. 1,3-Azulenedicarbaldehydes also reacted with 8 to give azulenes in 36 and 52% yields, respectively. This decarbonylation reaction was adopted to the selective synthesis of 3,3′-unsubstituted di(1-azulenyl)methane derivatives 7a—d. Acid-catalyzed condensation of 9a and b with paraformaldehyde or benzaldehyde afforded 3,3′-methylenedi(1-azulenecarbaldehyde)s, following this decarbonylation reaction gave the desired 7a—d as a sole product in 33—59% yields starting from 9a and b. Such decarbonylation is because of the ability of protonation of azulene ring in acidic condition and because of electron-donating properties of pyrrole ring. This reaction would serve as a new strategy for the protection of 1- and/or 3-positions of azulene ring.
The Reaction of Nitrile Oxide-Quinone Cycloadducts. III. Reinvestigation of the Base-Induced Isomerization of the 1 : 1 -C=C-Adducts of Aromatic Nitrile Oxides with 2,5- and 2,6-Dialkyl-Substituted p-Benzoquinones
Authors: Mukawa Takashi , Inoue Yukihiko , Shiraishi Shinsaku
Published: May 2005

The structure of the product obtained by the base-induced isomerization of the 1,3-dipolar cycloadduct of 2,5-di-t-butyl-p-benzoquinone with 2,6-dichlorobenzonitrile oxide was determined by X-ray analysis. The t-butyl group at the bridgehead position of the 1,3-dipolar cycloadduct migrated to the neighboring carbonyl carbon atom. This base-induced rearrangement took place with a bulky group, i. e., Et, i-Pr, t-Bu, and Bn at the bridgehead position of nitrile oxide-quinone cycloadducts in an alcoholic media. The driving force of this reaction is considered to be due to stabilization by aromatization from isoxazoline derivatives to isoxazole-fused p-quinol derivatives.
Processing and Performance of Electric Double-Layer Capacitors with Block-Type Carbon Nanotube Electrodes
Authors: Ma Renzhi , Liang Ji , Wei Bingqing , Zhang Bin , Xu Cailu , Wu Dehai
Published: May 2005

Two kinds of block-type porous materials of carbon nanotubes were fabricated. One was fabricated by hot-pressing without any binding materials, the other was synthesized through carbonization of a cured mixture of carbon nanotubes and phenol-formaldehyde resin. The specific surface area and total volume of the open pores were measured. Both are suitable for fabricating polarizable electrodes of electric double-layer capacitors (EDLCs). In addition, the block-type carbon nanotube electrodes enable one to fabricate a box-type cell. A cell with large capacitance, 150 F at 1.0 V, was developed by using sulfuric acid as the electrolyte.
Profiles of Carbon Dioxide Decomposition in a Dielectric-Barrier Discharge-Plasma System
Authors: Matsumoto Hiroshige , Tanabe Shuji , Okitsu Kenji , Hayashi Yuji , Suib Steven L
Published: May 2005

Decomposition of CO2 to CO and O2 in Ar stream has been investigated under atmospheric pressure by the use of a dielectric-barrier discharge plasma reactor. CO2 dissociation was found to proceed in accordance with the stoichiometry of 2 CO2 = 2 CO + O2 at considerable rates, which increased with increasing the input voltage, the CO2 concentration in Ar, and the heat of oxide formation of the corresponding metallic component used as the electrode. From kinetic and spectroscopic measurements, the major pathway of CO2 decomposition was speculated to be promoted by a synergetic effect between plasma excitations in the gas phase and catalytic actions of the electrode surface.
Metallo-Regulation of DNA Triple Helix Formation through Cooperative Dimerization of Two Oligonucleotides
Authors: Sueda Shinji , Ihara Toshihiro , Takagi Makoto
Published: May 2005

The DNA binding affinity of oligonucleotide carrying iminodiacetic acid (IDA) group is regulated by metal ion through cooperative dimerization mediated by formation of 2:1 complex of IDA with metal ion.
A Novel Organic Peroxyester as an Exclusive Source of tert-Butyl Radicals
Authors: Nakamura Tomoyuki , Watanabe Yasumasa , Tezuka Hiroshi , Busfield W Ken , Jenkins Ian D , Rizzardo Ezio , Thang San H , Suyama Shuji
Published: May 2005

A novel peroxyester, 1,1,2,2-tetramethylpropyl peroxypivalate 1b, has been synthesized and thermolyzed in cumene. The kinetic data show that the decomposition rate constant of 1b is about three times higher than that of tert-butyl peroxypivalate. The radical trapping technique employing 1,1,3,3-tetramethyl-2,3-dihydro-1H-isoindol-2-yloxyl has been used to study the decomposition mechanism of 1b. The results show that the thermolysis of 1b in cumene generates tert-butyl radicals exclusively.
Mössbauer Spectra of FePS3 and Its Intercalation Compounds
Authors: Sakai Hiroshi , Yamazaki Takashi , Shigematsu Toshihiko , Nakashima Satoru , Hinomura Tooru , Nasu Saburo
Published: May 2005

We succeeded in preparing FePS3 intercalated with pyridine and allylamine. In the XRD patterns of the intercalates the diffraction peaks corresponding to FePS3 were completely missing. The Mössbauer spectra are changed significantly by the intercalation, suggesting the charge transfer from guest molecules to the host matrix.
Direct Measurements of Stretching Force-Chain Ends Elongation Relationships of a Single Polystyrene Chain in Dilute Solution
Authors: Kikuchi Hirotsugu , Yokoyama Noritaka , Kajiyama Tisato
Published: May 2005

Mechanical stretching characteristics of a single polystyrene chain in a dilute solution was investigated with atomic force microscope. An entropic elasticity expressed by the extended Langevin function was observed in a force range below 200 pN and an extension range below 60 nm.
Extremely Efficient Catalysis of Immobilized Lipase in Ring-opening Polymerization of Lactones
Authors: Uyama Hiroshi , Suda Sakae , Kikuchi Hirofumi , Kobayashi Shiro
Published: May 2005

An immobilized lipase derived from Candida antarctica was used as catalyst for the ring opening polymerization of lactones. A small amount of the immobilized enzyme showed the extremely efficient catalysis in the lactone polymerization. The polymerization in the presence of 1-octanol enhanced the rate of reaction.
Thermally Responded Self-Aggregation of Ultrafine Particles Prepared by Modification of Monodisperse Colloidal Silica with Iron(II)-Bipyridyl Branched Polymer
Authors: Yoshinaga Kohji , Sasao Yoshiro
Published: May 2005

Monodisperse colloidal silica particles modified by Fe(II)-bipyridyl complex-branched, N-isopropylacrylamide-contained polymer showed self-aggregation via the ligand exchange among the particles in response to temperature elevation from 15 °C to 35 °C.
A Stepwise Selective Chlorination-Chemical Vapor Transport Reaction for Rare Earth Separation
Authors: Wang Zhi-Chang , Sun Yan-Hui
Published: May 2005

A stepwise selective chlorination-chemical vapor transport reaction results in the efficient separation of neighboring rare earth elements La, Ce, Pr, and Nd from their binary oxide mixtures.
Preparation of Thick Inorganic-organic Composite Films by Electrophoretic Sol-gel Deposition Using Organically Modified Silica Particles and Polyethylene Maleate
Authors: Hasegawa Koichi , Kunugi Shunsuke , Tatsumisago Masahiro , Minami Tsutomu
Published: May 2005

Thick inorganic-organic composite films composed of organically modified silica particles and polyethylene maleate were prepared by electrophoretic sol-gel deposition. The optimum amount of polyethylene maleate added was 1 mass% and that of ammonia water was 1 mass% to obtain thick films of ca. 20 μm in thickness with no open spaces among the particles.
Signal Transduction against the Terpenoid-Stimulation in the Liverwort Cells
Authors: Izumi Shunsuke , Hirata Toshifumi
Published: May 2005

Addition of bornyl acetate to the cultured cells of Marchantia polymorpha caused a rapid increase of H2O2 and cAMP in the intracellular level. cAMP agonist (Sp-cAMPS) activated the H2O2 formation, while cAMP antagonist (Rp-cAMPS), protein kinase A inhibitor H-89, and Ca2+ ions inhibited the H2O2 formation.
Beneficial Effect of Carbon Dioxide in Dehydrogenation of Ethylbenzene to Styrene over Zeolite-Supported Iron Oxide Catalyst
Authors: Chang Jong-San , Park Sang-Eon , Park Min Seok
Published: May 2005

In dehydrogenation of ethylbenzene with carbon dioxide over zeolite-supported iron oxide catalyst, ethylbenzene was predominantly converted into styrene by an oxidative manner. Carbon dioxide in this reaction played a role as an oxidant to greatly improve catalytic activity as well as coke resistance of catalyst.
Real Time Observation of Decomposition of Methanol on Ru(001)-p(2 × 2)-O by a Temperature Programmed ESDIAD/TOF System
Authors: Sasaki Takehiko , Itai Yuichiro , Iwasawa Yasuhiro
Published: May 2005

For the purpose of utilizing ESDIAD (Electron Stimulated Desorption Ion Angular Distribution) as a real time probe for surface chemical processes, we have developed a new instrument which can measure ESDIAD images and time of flight (TOF) spectra of desorbed ions in temperature programmed surface processes. TOF measurements are carried out to identify the mass of desorbed ions and to determine their kinetic energy distribution. This temperature-programmed (TP)-ESDIAD/TOF system was used to observe the decomposition processes of methanol on Ru(001)-p(2 × 2)-O. A halo pattern from the methyl group of methoxy species was observed at 100-200 K by the use of CH3OD, followed by a broad pattern from the methyl group at 230-250 K, and by a near-center pattern from the oxygen atom of CO above 300 K.
Extraction Behavior of Gallium(III) with 2-Methyl-5-hexyloxymethyl-8-quinolinol and 5-Hexyloxymethyl-8-quinolinol from Weakly Acidic Solution into Supercritical CO2 and Selective Separation of Gallium(III) from Aluminum(III)
Authors: Ohashi Kousaburo , Tatenuma Katuyoshi
Published: May 2005

The extraction behavior of gallium(III) with 2-methyl-5-hexyloxymethyl-8-quinolinol (HMO6Q) and 5-hexyloxymethyl-8-quinolinol (HO6Q) (Figure 1) into supercritical CO2 from weakly acidic solution was investigated. The extractability of gallium(III) is appreciably dependent on the temperature and pressure of supercritical CO2. Gallium(III) was separated fairly selectively from aluminum(III) with HMO6Q into supercritical CO2.
Stereocontrolled Synthesis of the BC Ring System of Taxol
Authors: Shiina Isamu , Iwadare Hayato , Sakoh Hiroki , Tani Yu-ichirou , Hasegawa Masatoshi , Saitoh Katsuyuki , Mukaiyama Teruaki
Published: May 2005

Optically active 2α,10β-dibenzyloxy-11β-(t-butyldimethylsiloxy)-7β-hydroxy-1α-(4-methoxybenzyloxy)–8β,15,15-trimethyl-4-methylene-trans-bicyclo[6.4.0]dodecan-9-one 2 that corresponds to BC ring system of Taxol was prepared from 8-membered ring enone 3 in high yield via stereoselctive Michael addition and successive intramolecular aldol cyclization. The above 8-membered ring enone 3 was synthesized from the linear optically active polyoxy-compound 4 by SmI2-mediated intramolecular aldol cyclization.
Imaging Antibody Molecules at Room Temperature by Contact Mode Atomic Force Microscope
Authors: Harada Akira , Yamaguchi Hiroyasu , Kamachi Mikiharu
Published: May 2005

Monoclonal antibodies (IgG and IgM) have been observed by atomic force microscopy (AFM) at room temperature depositing from solution onto a freshly cleaved highly oriented pyrolitic graphite (HOPG) surface.
Cooperation of Hydrogen Bonds for Mesophase Stabilization in Supramolecular Assemblies
Authors: Kato Takashi , Kondo Gohta , Kihara Hideyuki
Published: May 2005

The supramolecular complexes of 2,6-bis(acylamino)pyridines and mesoganic compounds containing carboxylterminated alkyl chains exhibit thermally stable mesomorphic behavior due to the cooperation of two different types of hydrogen bonds.
Controlled Assembly of Patterned Gold Thin Films Using Photolithographed Self-assembled Monolayers as Templates
Authors: Liu Junfu , Zhang Lingang , Mao Pansong , Chen Deying , Gu Ning , Ren Jiyun , Wu Yanpeng , Lu Zuhong
Published: May 2005

Patterned colloidal Au films were assembled from aqueous solution onto photolithographed self-assembled monolayers of (3-mercaptopropyl) trimethoxysilane films on silica. The colloidal Au closely replicated the mask patterns. The self-assembly were through Au-S covalent bounding. The present approach may be applicable to assembly of microelectronic circuits and microbiosensors.
Regioselective Ring-opening of Cyclopropyl Ketones with Organometallic Reagents
Authors: Ichiyanagi Tsuyoshi , Kuniyama Satoru , Shimizu Makoto , Fujisawa Tamotsu
Published: May 2005

Regioselective ring-opening reaction of cyclopropyl ketones was conducted successfully, in which the reaction of cyclopropyl phenyl ketone with trimethylaluminum catalyzed by nickel acetylacetonate gave the ring-opening product in up to 76% yield.
Synthesis of Optically Active Diols Bearing a Long Chain via Enzymatic Hydrolysis of Cyclic Carbonates
Authors: Matsumoto Kazutsugu , Shimojo Megumi , Hatanaka Minoru
Published: May 2005

PPL catalyzes the hydrolysis of racemic five-membered cyclic carbonates bearing a long chain with high enantioselectivity. Optically pure (S)-(+)-8-hydroxyhexadecanoic acid is effectively synthesized starting from (R)-4-(7-benzyloxy)heptyl-1,3-dioxolan-2-one and (S)-9-benzyloxynonane-1,2-diol, which are prepared via an enzymatic reaction.
Asymmetric Energy Exchange Observed in Two-beam Coupling Experiment on Immobilized Films of Bilayer Amphiphiles Possessing Carbazole and Nonlinear Optical Chromophores
Authors: Sasaki Takeo , Yoshimi Takeshi , Saga Miki , Ishikawa Yuichi
Published: May 2005

Amphiphilic compounds containing carbazole and a nonlinear optical (NLO) chromophore were synthesized and a two-beam coupling experiment was performed on a mutilayered film of a mixture of these amphiphiles. Asymmetric energy exchange was observed in a mutilayered film while no exchange was observed in an amorphous one.
Condensation of Cys(Acm)-Containing Peptide Segments with Silver Chloride as an Activator of Peptide Thioesters
Authors: Kawakami Toru , Aimoto Saburo
Published: May 2005

The undesirable removal of an acetamidomethyl (Acm) group in a Cys(Acm) residue is suppressed during the segment condensation of peptides, when silver chloride is used as an activator of the thioester moiety in a partially protected peptide thioester. The rate of segment condensation is sufficiently hifgh enough for its application to practical peptide synthesis.
Novel σ-π Alternating Polymers Having 2,2′-Bipyridyl in the Polymer Backbone and Their Ruthenium Complexes
Authors: Tokura Satoshi , Yashuda Takashi , Segawa Yusaburo , Kira Mitsuo
Published: May 2005

Novel σ-π alternating copolymers, poly(disilanylene-2-2′-bipyridine-5-5′-diyl) and poly(silylene-2-2′-bipyridine-5-5′-diyl) and their ruthenium complexes, were synthesized. The ruthenium complexes showed photoconductivity caused by metal-to-ligand charge-transfer excitation.
Photocoloration of Spironaphthoxazine Microcrystalline Powder by Femtosecond Laser Pulse Excitation
Authors: Asahi Tsuyoshi , Masuhara Hiroshi
Published: May 2005

Photocoloration of microcrystalline powder of a spirooxazine compound by femtosecond laser pulse excitation, depending on its intensity, is reported with transient absorption spectral measurements of the powder. The mechanism is discussed in terms of light induced local heating and succeeding cooling of a small volume in the microcrystal.
Pulse Radiolysis-Laser Flash Photolysis Study of Xanthene in 1,2-Dichloroethane/Carbon Tetrachloride
Authors: Sumiyoshi Takashi , Wu Feng , Shindo Toshihiko , Ueta Syohei , Sawamura Sadashi
Published: May 2005

The photochemistry of 9-xanthenyl radicals produced by pulse radiolysis of xanthene in 1,2-dichloroethane (1,2-DCE) and CCl4 was studied by means of successive laser flash photolysis. Photobleaching due to chlorine atom transfer from solvents to the excited 9-xanthenyl radical was observed with quantum yields of 0.04 and 0.29 in 1,2-DCE and CCl4, respectively.
Synthesis and Structure of [Cp*3(Ph2C2S2)Fe4S5(BF4)·Me2CO: Implication of the Flexible Fe4S5 Framework
Authors: Inomata Shinji , Hitomi Keiichi , Ogino hiroshi
Published: May 2005

A mixed ligand cluster, [Cp*3(Ph2C2S2)Fe4S5](BF4)·Me2CO, was synthesized and its X-ray crystal structure was determined. From the comparison of this structure with those of Cp*3(Ph2C2S2)Fe4S5·THF, [Cp*3(Ph2C2S2)Fe4S5](PF6)·2Me2CO, and [Cp*3(Ph2C2S2)Fe4S5](PF6)2·Me2CO which have been reported previously, it is concluded that the Fe4S5 core of the clusters is flexible and easily undergoes deformation.
Crystal Size Dependence of Emission from Perylene Microcrystals
Authors: Kasai Hitoshi , Kamatani Hirokazu , Yoshikawa Yuko , Okada Shuji , Oikawa Hidetoshi , Watanabe Akira , Itoh Osamu , Nakanishi Hachiro
Published: May 2005

In this study, we found that, in perylene microcrystals, luminescence peak position from free-exciton state was gradually shifted to high energy side with reducing the crystal size, even if the microcrystals were fabricated by different kinds of preparation techniques. The life time of luminescence from self-trapped exciton state became shorter when the crystal size reduced. The main reason was estimated to be based on the change of lattice state.
Preparation of Poly(imino-1,3-phenylene) and Its Related Polymer by Palladium-catalyzed Polycondensation
Authors: Kanbara Taraki , Izumi Kiyoaki , Nakadani Yoshiko , Narise Tomoko , Hasegawa Kiyoshi
Published: May 2005

Palladium-catalyzed polycondensation reactions of 1,3-dibromobenzene with 1,3-phenylenediamine and 3-bromoaniline afforded soluble poly(imino-1,3-phenylene) in mederate to good yields. Poly(imino-2,6-pyridinediylimino-1,3-phenylene) was also prapared in an analogous way.
Living Coordination Polymerization of Alkylallenes by π-Allylnickel Catalyst: Observation of an Extremely High Polymerizability of 1,2-Cyclononadiene
Authors: Takagi Koji , Tomita Ikuyoshi , Endo Takeshi
Published: May 2005

The coordination polymerization of cyclic allenes by [(π-allyl)NiOCOCF3]2 was investigated to produce polymers with narrow molecular weight distributions in high yields. The polymerization proceeded in a living mechanism, and the molecular weight of the resulting polymer had a linear relationship with the monomer feed ratio. Especially, the polymerization of 1,2-cyclononadiene (i.e., a monomer with substantial ring strain) proceeded dramatically fast compared with acyclic monomers.
Tetranuclear Cobalt(III) Complex Having the Cubane Co4O4 Core: Synthesis and Structural Analysis of the Complex Containing (2-Pyridylmethyl)glycine
Authors: Ama Tomoharu , Okamoto Ken-ichi , Yonemura Toshiaki , Kawaguchi Hiroshi , Takeuchi Akiyoshi , Yasui Takaji
Published: May 2005

A tetranuclear cobalt(III) complex with the cubane Co4O4 core, [Co4(pg)4(μ3-O)4] (Hpg: N-(2-pyridylmethyl)glycine), was prepared and the structure was determined by the X-ray diffraction method. This complex has the four N–H···O intramolecular hydrogen-bonds between the amino group on one of the four cobalt atoms and the carboxyl group on another cobalt atom. Its neutral aqueous solution showed no spectral change for at least 3 days.
Synthesis of the C8-C15 Segment of (+)-Discodermolide
Authors: Miyazawa Masahiro , Oonuma Satoshi , Maruyama Kimiyuki , Miyashita Masaaki
Published: May 2005

Succeeding to the preceding paper, stereoselective synthesis of the C8-C15 segment of (+)-discodermolide (1), the marine natural product having the potent immunosuppressive activity, is described in which the contiguous asymmetric centers at C11 and C12 positions were stereospecifically constructed via the methylation of an epoxy alcohol with lithium dimethylcuprate.
A Novel Tetrathiafulvalenoquinodimethane Derivative Exhibiting Strong Electronic Absorption in a Near-Infrared Region
Authors: Ueda Kazumasa , Iwamatsu Masaki , Sugimoto Toyonari , Fujita Hideo
Published: May 2005

A novel donor (dihydrotetrathiafulvalene)/acceptor (ethanediylidene-2,2′-bis(indane-1,3-dione) compound was synthesized, which very interestingly exhibited its longest wavelength absorption till a near-infrared region (> 800 nm) without significant absorptions in the visible region.
The Effects of Imidazolato-bridge and Zinc on a Model Complex for the Active Site of Cu-Zn SOD
Authors: Kawabata Satoshi , Soma Tatunori , Ichikawa Kazuhiko
Published: May 2005

The SOD-like activity of model dicopper complexes was described. The role of imidazolato-bridged zinc was revealed by biochemical and electrochemical methods.
Efficient Perparation of Racemic Isomers of ansa-Zirconocene Complexes with a Vinyl Substituted Silylene Bridge
Authors: Huhn Thomas , Suzuki Noriyuki , Yamaguchi Yoshitaka , Mise Takaya , Chihara Teiji , Wakatsuki Yasuo
Published: May 2005

The reaction of dilithiated silylene-bridged Cp-ligands, whose silylene had one or two vinyl substituents, with ZrCl4 gave racemo-rich mixtures of the complex RR′Si(C5H2-2,4-Me2)2ZrCl2 (1: R = vinyl, R′ = Me, rac/meso = 77/23, 4: R = R′ = vinyl, rac/meso = 77/23). The pure racemic complex 1-rac was isolated after several recrystallization processes in a satisfactory yield (31%, rac/meso >99⁄1) and was structurally characterized. Polymerization of propylene with 1-racMAO gave highly isotactic polypropylene.
Synthesis of the Central Heterocyclic Skeleton of an Antibiotic, A10255
Authors: Umemura Kazuyuki , Ikeda Shin , Yoshimura Juji , Okumura Kazuo , Saito Hiroyuki , Shin Chung-gi
Published: May 2005

The central heterocylic skeleton (13) of an antibiotic, A10255, was synthesized by stepwise introduction of two groups into the 2,6-positions of 3-{(4-ethoxycarbonyl)-2-thiazolyl} pyridine, via 17 steps in 4.8% total yield.
A Novel Method of Real-time Size Control of Nanoaggregates by AFM
Authors: Su Ming , Bai Chunli , Tian Fang , Ma Jin , Liu Maozi , Wang Chen
Published: May 2005

AFM enables the direct size control of nan-aggregate when the growth process is real-time observed. The method requires the optimal adsorption of desired molecule on the tip of AFM.
Laser Flash Photolysis Study on Photochemical and Photophysical Properties of C60 Fine Particle
Authors: Fujitsuka Mamoru , Kasai Hitoshi , Masuhara Akito , Okada Shuji , Oikawa Hidetoshi , Nakanishi Hachiro , Watanabe Akira , Ito Osamu
Published: May 2005

Photophysical and photochemical properties of C60 fine particle which was prepared by the reprecipitation method were examined by nanosecond laser flash photolysis. Triplet-triplet annihilation due to migration of triplet state within the fine particle was observed. Photoexcitation of the fine particle under the presence of electron donor resulted in photoinduced electron transfer. The reaction rate was one order smaller than that in solution suggesting interfacial electron transfer.
Cleavage of C–H Bond of Methane on Intermediate Q of Methane Monooxygenase
Authors: Yoshizawa Kazunari , Ohta Takehiro , Shiota Yoshihito , Yamabe Tokio
Published: May 2005

A possible reaction pathway for the C–H bond cleavage of methane on intermediate Q of methane monooxygenase is studied theoretically. We propose that the activation of methane C–H bond by Q, suggested to involve a high valent Fe2(μ-O)2 diamond core, should occur through the formation on the Q(CH4) complex with an Fe–C bond and Fe–H bonds, followed by a concerted H atom abstraction via a four-centered transition state.
Synthesis of New Adsorbent Copper(II) Terephthalate
Authors: Mori Wasuke , Inoue Fumie , Yoshida Keiko , Nakayama Hirokazu , Takamizawa Satoshi , Kishita Michihiko
Published: May 2005

Copper(II) terephthalate absorbs a large amount of gases such as N2, Ar, O2, and Xe. The maximum amounts of absorption of gases were 1.8, 1.9, 2.2, and 0.9 mole per one mole of the copper(II) salt for N2, Ar, O2, and Xe, respectively, indicating that the gases were not adsorbed on the surface but occluded within the solid. The porous structure of copper(II) terephthalate, in which the gas is occluded, is deduced from the temperature dependence of magnetic susceptibilities and the linear structure of terephthalate.
Conversion of Cephem into Penam/Penem through Sequential Ring-opening/Recyclization in an Al/BiCl3/AlCl3 System
Authors: Tanaka Hideo , Tokumaru Yoshihisa , Kameyama Yutaka , Torii Sigeru
Published: May 2005

A sequential reductive ring-opening/recyclization reaction of 3-substituted Δ3-cephems into 2-exo-methylenepenams and/or 2-methylpenems was successfully performed by treatment with Al/BiCl3/AlCl3 in NMP (N-methyl-2-pyrrolidinone). When the reaction was carried out in methanol, 3-norcephalosporin was formed as a major product.
A Kinetic Investigation for Substrate Specificity of a Hydrolytic Abzyme
Authors: Wada Yumiko , Yamamoto Masayoshi , Itoh Isamu , Ono Mitsunori
Published: May 2005

Catalytic antibody 4A1 showed a significant rate acceleration against substrates which are different from the structure of the inducing hapten in the carrier-proximal region. Kinetic analysis of Km and kcat values as well as the KD values of the corresponding transition-state analogues indicated that the rate enhancement resulted from stabilization of the transition-state in the cleavage reaction.
Cu(I)/Pd(0)-Catalyzed Cross-Coupling Reaction of Alkynylsilanes with Aryl or Alkenyl Triflates: “Sila”-Sonogashira-Hagihara Coupling
Authors: Nishihara Yasushi , Ikegashira Kazutaka , Mori Atsunori , Hiyama Tamejiro
Published: May 2005

Alkynylsilanes reacted with aryl or alkenyl triflates in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuCl in DMF to give the corresponding cross-coupling, namely “sila”-Sonogashira-Hagihara coupling, products in good to excellent yields. The present reaction is highly effective for one-pot synthesis of unsymmetrical diarylacetylenes.
New Types of Coupling Reactions of Some Nitriles on Ruthenium Complexes
Authors: Hiraki Katsuma , Kinoshita Yuji , Ushiroda Hiroyo , Koyama Shuji , Kawano Hiroyuki
Published: May 2005

A hydridoruthenium(II) complex [RuClH(CO)(PPh3)3] reacts with o-toluonitrile and water at 120 °C to give a novel five-membered cyclometallated complex, [Ru(C6H3MECH=NCH2C6H4Me-o)Cl(CO)(PPh3)2]. The hydrido complex reacts with benzoylacetonitrile at 80 °C to form a six-membered chelate complex, [RuCl{O=C(Ph)C(CN)=C(CH2COPh)NH}(CO)(PPh3)2].
Preparation of Hyperbranched Polymethacrylates by Self-Condensing Group Transfer Polymerization
Authors: Sakamoto Kenkichi , Aimiya Takuji , Kira Mitsuo
Published: May 2005

Hyperbranched polymethacrylates were synthesized by group transfer self-condensation polymerization of 2-(2-methyl-1-triethylsiloxy-1-propenyloxy)ethyl methacrylate. The hyper-branched structure of the polymer was characterized by 13C NMR spectroscopy. The extent of the branching depended on the nucleophilic catalysts used for activation of the monomer.
Remarkable Enhancement of Lipase Catalytic Activity: Combined Effects of Acyl Donor and Thiacrown Ether Additive during Trans-esterification of 5-Phenyl-1-penten-3-ol
Authors: Takagi Yumiko , Ino Rieko , Kihara Hiroshi , Itoh Toshiyuki , Tsukube Hiroshi
Published: May 2005

The Pseudomonas cepacia lipase-catalyzed trans-esterification of 5-phenyl-1-penten-3-ol was drastically accelerated by 5 mol% of a thiacrown ether additive. The reaction profile was strongly dependent on the nature of the vinyl esters as the acyl donor; the highest acceleration rate was recorded with vinyl chloroacetate, while the highest enantioselectivity was obtained using vinyl acetate.
Photoinduced Formation of [fac-Re(bpy)(CO)3CN] from [fac-Re(bpy)(CO)3(4-CNpy)]+ (bpy = 2,2′-bipyridine, py = pyridine): CN Group Rearrangement of a Cyanopyridine Ligand onto Central Metal
Authors: Hori Hisao , Ishihara Jun , Koike Kazuhide , Takeuchi Koji , Ibusuki Takashi , Ishitani Osamu
Published: May 2005

[fac-Re(bpy)(CO)3CN] was photochemically formed from [fac-Re(bpy)(CO)3(4-CNpy)]+ with a 53% yield using 365 nm irradiation in the presence of triethanolamine (TEOA). This rearrangement proceeds via formation of solvent complexes [fac-Re(bpy)(CO)3(DMF)]+ and [fac-Re(bpy)(CO)3(TEOA)]+.
Investigation on the Conformational Behavior of Kemp’s Triacid and Its Isomer Using Tb3+ as a Fluorescent Probe
Authors: Luján-Upton Hannia A , Okamoto Yoshiyuki
Published: May 2005

Complexes of terbium ion, Tb3+, and two cyclic acids, Kemp’s triacid and its configurational isomer, ((1α,3α,5β)-1,3,5-trimethyl-1,3,5-cyclohexanetricarboxylic acid) were made. Differences in complexation were investigated by fluorescence intensity and lifetime measurements. Intensity measurements showed the Kemp’s / Tb3+ complex to be five times more fluorescent than the isomeric complex. Lifetime measurements supported the intensity data showing an average of 2.7 water molecules bound to Tb3+ in the Kemp’s / Tb3+ complex. Four waters were retained in the isomeric complex.
Synthesis and Properties of Di-μ-superoxo Dinuclear Cobalt(II, III) Complex
Authors: Hayashi Yoshihito , Obata Masahiro , Suzuki Masatatsu , Uehara Akira
Published: May 2005

A novel di-μ-superoxo mixed-valence dicobalt(II, III) complex, [(Me3tacn)2CoIICoIII(μ-OH)(μ-O2)2]2+ has been prepared from a μ-peroxo complex, [(Me3tacn)2(acac)2CoIII2(μ-O2)]2+.Electrochemical studies demonstrated the reversible redox behavior among the oxidation states of Co(III, III), Co(III, II), and Co(II, II).
A Novel Bimacrocyclic Ni(II) Complex Comprised of Both Trans-I and Trans-III Configurations
Authors: Mochizuki Katsura
Published: May 2005

A new configurational isomer of the Ni(II) complex with a C–C bridged bimacrocycle, where one 14-membered N4 macrocycle adopts a trans-I (RSRS) configuration and the other a trans-III (RRSS) configuration, was isolated and its structure was confirmed by X-ray structural analysis.
Inclusion Compounds of Hyodeoxycholic Acid and the Crystal Structure of a 1:1 Complex between the Acid and Pyridine
Authors: Miyake Yasuhito , Matsuura Yoshiaki , Sada Kazuki , Miyata Mikiji
Published: May 2005

Hyodeoxycholic acid forms inclusion crystals with aromatic amines such as pyridine, aniline and toluidines. The crystal structure of a 1:1 inclusion compound of hyodeoxycholic acid with pyridine was determined.
New Methoxy-Substituted Tritylamine Linkers for the Solid Phase Synthesis of Protected Peptide Amides
Authors: Meisenbach Mark , Voelter Wolfgang
Published: May 2005

Syntheses of new methoxy-substituted tritylamine linkers in only four steps for the solid phase synthesis of peptide amides via the Fmoc/tBu strategy are described and their properties compared. Peptide amides can be cleaved under mild acidic conditions in high purity in their protected of deprotected form.
Solid-state Synthesis of Novel 3,9-Diazatetraasteranes
Authors: Hilgeroth Andreas
Published: May 2005

A novel solid-state synthesis of 3,9-diazatetraasteranes is reported, giving polyfunctionalized derivates in a single-step reaction with nearly quantitative yields by photochemically induced [2+2]cycloaddition reactions.
A New Ruthenium-catalyzed Reaction with Propargyl Alcohol: Cyclopropanation of Norbornene
Authors: Kikuchi Hidetoshi , Uno Mitsunari , Takahashi Shigetoshi
Published: May 2005

Cationic (η5-cyclopentadienyl)tris(acetonitrile)ruthenium complexes catalyze a new reaction of propargyl alcohol with norbornene in methanol to give a cyclopropanation product, acetyltricyclooctane, in a quantitative yield.
A New Ni(dmise)2 Complex N,N-dimethylpiperidinium[Ni(dmise)2]2, with Stable Metallic State
Authors: Sato Akane , Kobayashi Hayao , Kobayashi Akiko
Published: May 2005

A new Ni(dmise)2 conductor, N,N-dimethylpiperidinium[Ni(dmise)2]2 (dmise = 2-selenoxo-1,3-dithiole-4,5-dithiolate) is metallic down to 2 K. In contrast to the normal metallic nature of this complex, the magnetic susceptibility was unexpectedly large and temperature dependent (χRT = 8.4 × 10−4 emu mol−1). Ni(dmise)2 molecules are arranged in the so-called “spanning overlap mode”.
Migration of Copper Ions in Cu-MFI without Destruction of Zeolite Lattice of Dealumination upon Hydrothermal Treatment at 923 K
Authors: Iwamoto Masakazu , Wang Jie , Sperati Karla M , Sajiki Toshiya , Misono Makoto
Published: May 2005

The hydrothermal treatment of Cu-MFI at 923 K resulted in great change in the IR and ESR spectra, whereas yielded a little change in the XRD, surface area, and 27Al MASNMR measurements. It has been suggested that Cu ions migrated to 5-membered oxygen ring sites due to the thermal treatment, which causes the deactivation of the catalyst.
Highly Selective Reduction of NO in Excess Oxygen through the Intermediate Addition of Reductant (IAR) between Pt- and Zn-MFI Zeolites
Authors: Iwamoto Masakazu , Zengyo Tetsu
Published: May 2005

Ethene has been added as reductant of NO in excess oxygen between an oxidation (Pt-MFI) and a reduction catalysts (Zn-MFI). The efficiency of ethene, namely the ratio of the amount of NO reduced to that of ethene consumed, reached about 2 and was much higher than that of conventional reduction on Cu-MFI.
Carbon Monoxide Oxidation Characteristics Over the Al2O3-supported CeO2-ZrO2 Catalysts Prepared by the Microemulsion Method
Authors: Masui Toshiyuki , Fujiwara Kazuyasu , Peng Yumin , Machida Ken-ichi , Adachi Gin-ya
Published: May 2005

Ceria-zirconia ultrafine particles supported on Al2O3 powders by the microemulsion method, CeO2-ZrO2/Al2O3, provided the high CO oxidation activity than that of the same catalyst prepared by the conventional co-precipitation method.
Conversion of the Valence States of 57Fe Atoms Produced in 57Co-labelled [Co(pyridine)2Ni(CN)4]
Authors: Sato Takuma , Ambe Fumitoshi , Kitazawa Takafumi , Sano Hirotoshi , Takeda Masuo
Published: May 2005

Emission Mössbauer spectra of the title compound measured below 80 K consist of three components ascribed to two Fe(II) high-spin states and one Fe(III) low-spin state. It was concluded that a part of the Fe(II) high-spin species converts to an Fe(III) high-spin species above 210 K, based on the comparison of the results with temperature-depending spin-crossover transition of the isomorphous compound, [Fe(py)2Ni(CN)4].
Hydroformylation of ω-Functionalized 1,1-Disubstituted Alkenes and Its Use Toward the Synthesis of (±)Muscone
Authors: Takahashi Takashi , Machida Kazuhiro , Kido Yoichi , Nagashima Kensuke , Ebata Satoshi , Doi Takayuki
Published: May 2005

The rhodium-catalyzed hydroformylation of ω-functionalized 1,1-disubstituted alkenes and the synthesis of (±)-muscone using this hydroformylation and cyanohydrin alkylation are described.
Resonance Raman Characterization of Antimony(III) Hyperporphyrin
Authors: Teraoka Junji , Ishimaru Hirohito
Published: May 2005

The resonance Raman spectra of a hyperporphyrin, (octaethylporphyrinato) antimony (III) chloride [Sb(OEP)]Cl, have been measured using excitations within a split Soret band in the near-UV and visible regions. No evidence could be found for a possibility that either of the Soret bands had a charge transfer character.
Structure and Stereodynamics of N-Ethyl-N-9-triptycylacetamide: Co-existence of Z- and E-Isomers in a Single Crystal and Pyramidal Amide Nitrogen Both in Crystal and in Solution
Authors: Yamamoto Gaku , Tsubai Natsuko , Murakami Hiroaki , Mazaki Yasuhiro
Published: May 2005

A single crystal of N-ethyl-N-9-triptycylacetamide contains the Z- and E-isomers in a ratio of 1 : 1. The amide nitrogen atom in either isomer is significantly pyramidalized. Either of the isomers in solution is shown to adopt a similar conformation with the pyramidal nitrogen as in the crystalline state.
Fabrication of Ordered Diamond/metal Nanocomposite Structures
Authors: Masuda Hideki , Yasui Kenji , Watanabe Mitsuo , Nishio Kazuyuki , Rao Tata N , Fujishima Akira
Published: May 2005

Highly ordered diamond/Au nanocomposite structures were fabricated by preparing a honeycomb structured diamond film and subsequent Au deposition into holes by vacuum deposition. The cross-sectional SEM image of the composite film showed Au nanodots at the bottom of the holes. The optical absorption spectrum of the composite film showed a characteristic absorption due to the surface plasmon resonance at the wavelength of ~520 nm, indicating the possible application of honeycomb diamond in optoelectronics.
Synthesis and Characterization of Bis(iminopyrrolyl)zirconium Complexes
Authors: Matsuo Yutaka , Mashima Kazushi , Tani Kazuhide
Published: May 2005

Diamido and dichloro zirconium complexes having two iminopyrrolyl ligands, Zr(Net2)2(pyr)2 (2a–e) (pyr = 2-(N-aryliminomethyl)pyrrolyl) and ZrCl2(pyr)2 (3a–e), were prepared. The cis-configuration of diamido and dichloro moieties was elucidated on the basis of NMR spectroscopy as well as by a crystallographic study for complex 3a. We demonstrated that these zirconium complexes became catalyst precursors for the polymerization of ethylene in the presence of excess amounts of methylaluminoxane.
Generation of Hydrogen from Methanol in a Dielectric-Barrier Discharge-Plasma System
Authors: Tanabe Shuji , Matsuguma Hiroshi , Okitsu Kenji , Matsumoto Hiroshige
Published: May 2005

The decomposition of CH3OH was investigated in a dielectric-barrier discharge-plasma induced by low power from 0.27 to 6.40 Wh(Ncm3)−1. The maximum CH3OH conversion of 80% into H2 was achieved with CO or CO2 being the other major product, respectively, in the absence or presence of water.
Effect of Preparation Conditions of Titanium Oxide on Dinitrogen Fixation to Ammonium Salt
Authors: Hoshino Katsuyoshi , Kitamura Takashi
Published: May 2005

Dinitrogen fixation to solid needles of ammonium perchlorate was found to occur upon white light irradiation to composite systems of poly(3-methylthiophene) and titanium oxides (native, thermally-grown, and sputtered oxides) under ambient conditions of temperature and pressure.
Synthesis and Curing of Crosslinkable Polyphenols from Urushiol Analogues
Authors: Tsujimoto Takashi , Ikeda Ryohei , Uyama Hiroshi , Kobayashi Shiro
Published: May 2005

New crosslinkable polyphenols were designed on the basis of model “urushi” and synthesized by oxidative polymerization of urushiol analogues, phenol derivatives bearing an unsaturated group. The polyphenols were readily cured to give crosslinked polymeric films with high gloss surface.
Sonochemical Reactions of Lead Tetraacetate with 4-Substituted Styrenes
Authors: Ando Takashi , Kimura Takahide , Levêque Jean-Marc , Fujita Mitsue , Luche Jean-Louis
Published: May 2005

A good linear free energy relationship was observed between the radical reactivity of the sonochemical reactions of 4-substituted styrenes with lead tetraacetate and the vapor pressure of the styrenes, indicating a probable control of the process by an intra-bubble activation.
New Treatment Methods for Waste Water Containing Chloride Ion Using Magnesium–Aluminum Oxide
Authors: Kameda Tomohito , Miyano Yoshinori , Yoshioka Toshiaki , Uchida Miho , Okuwaki Akitsugu
Published: May 2005

The removal of hydrochloric acid utilizing magnesium-aluminum oxide (Mg–Al oxide), as prepared by the thermal decomposition of hydrotalcite (HT), was investigated. Cl− in hydrochloric acid can be removed almost 100% by adding 1.75 times the stoichiometric quantity of Mg0.70Al0.20O at 60 °C for 1 h. Mg2+ and Al3+ in solution after the reaction were not recognized, because the solution was weakly alkaline.
Nonlinear Optical Response of Colloidal Gold Nanoparticles Studied by Hyper-Rayleigh Scattering Technique
Authors: Shen Yao-chun , Tang Zuming , Gui Minzhi , Cheng Jiqi , Wang Xing , Lu Zuhong
Published: May 2005

Hyper-Rayleigh scattering (HRS) technique is used to study the nonlinear optical response of nanocrystalline gold particle suspensions. The signal intensity measured at 400 nm has a cubic dependence on the pump laser energy at 1064 nm, indicating that the measured signal is due to a third-order nonlinear optical process, namely three-photon excited fluorescence (3PF). To the best of our knowledge, this is the first experimental observation of 3PF for colloidal gold nanoparticle suspensions.
Intercalation of Spirooxazine Induced by Zinc Cation Chelation in Montmorillonite and Its Photochromic Behavior
Authors: Nishikiori Hiromasa , Sasai Ryo , Arai Norio , Takagi Katsuhiko
Published: May 2005

Spirooxazine (SPO) was introduced into hydrophobically modified montmorillonite dispersed in acetone under UV illumination in the presence of zinc ions. The fluorescence spectra of the samples exhibited photochromic behavior arising from the photo-induced interconversion between the original species of SPO and the Zn-chelated complex of the SPO-derived merocyanine.
Synthesis of Microporous Silica in the Presence of Dodecyldimethylbenzylammonium Chloride Surfactant
Authors: Yuan Zhong-Yong , Zhou Wuzong , Peng Lian-Mao
Published: May 2005

Microporous silicas with pore sizes in the range intermediate between traditional microporous and mesoporous materials have been synthesized by using dodecyldimethylbenzylammonium chloride as a template. These microporous silicas can be synthesized by either acidic S+X−I+ or basic S+I− assembly pathways and consist of disordered channels with almost identical pore sizes of 12.2 Å in both cases. Their BET surface areas are larger than 1000 m2/g after being calcined in air.
A Novel Molecular System for Nitric Oxide Detection with High Sensitivity
Authors: Katayama Yoshiki , Soh Nobuaki , Koide Kazuhiro , Maeda Mizuo
Published: May 2005

A novel molecular switching system was developed for the direct detection of endogenous nitric oxide. The system is comprised from an Fe(II)–dithiocarbamate complex in which TEMPOL molecule coordinates to the centered iron through a redox interaction. Nitric oxide binds to the iron to liberate the TEMPOL. The system will be potentially useful for the monitoring of endogenous nitric oxide.
Electrochemical Behavior of Graphite Electrode for Lithium Ion Batteries in Mn and Co Additive Electrolytes
Authors: Kumagai Naoaki , Komaba Shinichi , Kataoka Yoichi , Koyanagi Makoto
Published: May 2005

Dissolution of Mn into an electrolyte from LiMn2O4 in Li ion cell is researched recently. To study an influence of the dissolved manganese species on performance of negative electrode, electrochemical behavior of graphite was investigated in LiClO4 solution containing Mn2+ by dissolving Mn(ClO4)2. During charging, manganese ions were firstly electroreduced on the electrode, followed by Li intercalation into graphite. Mn deposition was confirmed after charge-discharge test, furthermore, the reversible capacity of lithium intercalation was decreased. The results were compared to those in a cobalt additive electrolyte.
Polymeric and Monomeric Forms of a Schiff Base–Nitridomanganese(V) Complex. Synthesis and Crystal Structure
Authors: Tsuchimoto Masanobu , Iwamoto Hirofumi , Kojima Masaaki , Ohba Shigeru
Published: May 2005

A novel polymeric nitridomanganese(V) complex with a Schiff base ligand [MnN(salpn)] (H2(salpn): N,N′-disalicylidene-1,3-propanediamine) (1) was prepared by photolysis of the azidomanganese(III) complex, [MnN3(salpn)] in acetonitrile. The monomeric complex (2) was obtained by recrystallization of 1 from methanol. X-Ray crystal structure analyses of 1 and 2 were carried out. The brown complex 1 has a linear ···Mn≡N···Mn≡N··· chain structure.
Cherenkov Counting Efficiencies for β−-Emitters in Dry State in Glass Vials
Authors: Morita-Murase Yuko , Murakami Isao , Homma Yoshio
Published: May 2005

Cherenkov counting efficiencies for standardized β−-emitters in the dry state at the centre of air-filled glass vials were measured with a liquid scintillation spectrometer. Cherenkov counting efficiencies, which are plotted as a function of the average energy of β−-particles and the internal conversion electrons, give a straight line on log–log scale.
Selective Hydrogen Production from Cellulose at Low Temperature Catalyzed by Supported Group 10 Metal
Authors: Usui Yoko , Minowa Tomoaki , Inoue Seiichi , Ogi Tomoko
Published: May 2005

Cellulose, a major component of woody biomass, reacts in hot-compressed water at 350 °C and 160–200 atm in the presence of a supported group 10 metal catalyst (2 wt%) for 10 min to give gas, consisting of hydrogen, carbon dioxide, and methane. Hydrogen was produced in high yield (8.1 mmol/g cellulose) and high selectivity (H2/CH4 = ca. 6) catalyzed by a supported Ni, Pd, or Pt. Among them, Pd supported on Al2O3 particularly had highest catalytic activity for this gasification.
Tetrahedral Distortion in Copper(II) Complexes of (−)-Sparteine and Its Effect on the Oxygen Adduct Formation
Authors: Funahashi Yasuhiro , Nakaya Kaori , Hirota Shun , Yamauchi Osamu
Published: May 2005

The Cu(II) complexes of (−)-sparteine (Sp) have been revealed to have tetrahedrally distorted structures in both monomeric and hydroxo-bridged dimmeric forms due to the steric requirements of Sp. Resonance Raman and UV absorption spectra indicated that the Cu(I) complex of Sp reacted with O2 at −80 °C to form a distorted CuIII2(µ–O)2 structure.
First Asymmetric Photochemistry with Nucleosides and DNA: Enantiodifferentiating Z–E Photoisomerization of Cyclooctene
Authors: Wada Takehiko , Sugahara Norimitsu , Kawano Mahito , Inoue Yoshihisa
Published: May 2005

Thymidine and uridine, as well as calf thymus DNA (ctDNA), have been shown for the first time to function as chiral photosensitizers in aqueous solution, to effect the enantiodifferentiating photoisomerization of (Z)-cyclooctene, giving the chiral (E)-isomer in enantiomeric excesses of up to 15%.
Extremely High Enantiomer Recognition in HPLC Separation of Racemic 2-(Benzylsulfinyl)benzamide Using Cellulose Tris(3,5-dichlorophenylcarbamate) as a Chiral Stationary Phase
Authors: Chankvetadze Bezhan , Yamamoto Chiyo , Okamoto Yoshio
Published: May 2005

An extremely high enantioselectivity of cellulose tris(3,5-dichlorophenylcarbamate) was found when it was used as a chiral stationary phase (CSP) in high-performance liquid chromatography (HPLC). The enantioseparation factor (α = 112) reported in this system for 2-(benzylsulfinyl)benzamide seems to be the highest among many enantiomer-differentiating separations using polysaccharide derivatives as CSPs.
Effective Activation of ‘Armed’ Thioglycoside with a New Combination of Trityl Tetrakis(pentafluorophenyl)borate [TrB(C6F5)4] and N-(Ethylthio)phthalimide (PhthNSEt)
Authors: Jona Hideki , Takeuchi Kazuya , Saitoh Terunobu , Mukaiyama Teruaki
Published: May 2005

Glycosylation of the ‘armed’ thioglycoside with various glycosyl acceptors is promoted by using a combination of stoichiometoric amount of N-(ethylthio)phthalimide (PhthNSEt) and catalytic amount of trityl tetrakis(pentafluorophenyl)borate [TrB(C6F5)4], and is successfully applied to one-pot ‘armed–disarmed’ sequential synthesis of trisaccharides.
Facile Synthesis of Optically Active Tertiary Alcohol Building Blocks by Stereospecific C–H Insertion Reaction of Dichlorocarbene with Secondary Alcohol Derivatives
Authors: Masaki Yukio , Arasaki Hideki , Shiro Motoo
Published: May 2005

Stereospecific C–H insertion of dichlorocarbene generated from a system CHCl3/50%NaOH/cetyltrimethylammonium chloride (as a PTC) proceeded at the carbinol carbon in the reaction of chiral secondary alcohol derivatives to provide α-dichloromethylated tertiary alcohol derivatives with complete retention of configuration.