bluuebunny/crossref_metadata_2025 huggingface dataset:
127I NUCLEAR MAGNETIC RESONANCE STUDIES ON THE INTERACTION OF IODIDE ION WITH HORSERADISH PEROXIDASE
Authors: Sakurada Junji , Hosoya Toichiro , Shimizu Toru , Hatano Masahiro
Published: July 2006

The binding of I− to horseradish peroxidase was studied with 127I NMR technique. The broadened line width of I−/enzyme solution was further increased remarkably by decreasing pH. The change of 127I NMR line width of the I−/enzyme solution caused by decreasing pH bore resemblance to the change of iodide oxidation catalyzed by the enzyme at acidic pH.
A STATE ANALYSIS METHOD OF TRANSITION-METAL ELEMENTS BY AN ELECTRON PROBE MICROANALYZER
Authors: Fujimori Haruo , Iba Hajime , Komori Itaru
Published: July 2006

It was shown that the chemical state of nickel or cobalt could be identified by the state analysis method utilizing the 9th-order Kα1 line. Probable factors of the X-ray intensity variation with chemical state were the self-absorption, the L2L3M4,5 Coster–Kronig process, and the pseudo Lβ emission.
A MILD AND EFFICIENT DEBROMINATION OF VICINAL DIBROMOALKANES WITH SODIUM TELLURIDE PREPARED FROM TELLURIUM AND RONGALITE
Authors: Suzuki Hitomi , Inouye Masahiko
Published: July 2006

Vicinal dibromoalkanes are debrominated to alkenes with remarkable ease by treatment with sodium telluride prepared from tellurium and Rongalite in aqueous alkaline medium.
ATTEMPTED ISOLATION OF MONOMERIC IMINOPHOSPHINES. FORMATION OF A STERICALLY PROTECTED IMINOPHOSPHINE P-SULFIDE AND DETECTION OF IMINOPHOSPHINES
Authors: Yoshifuji Masaaki , Shibayama Katsuhiro , Toyota Kozo , Inamoto Naoki , Nagase Shigeru
Published: July 2006

A monomeric iminophosphine was observed by the desulfurization of the corresponding p-sulfide; the structure of the sulfide was discussed in terms of ab initio calculation; several attempts to isolate sterically protected iminophosphines were described.
BASICITY OF ROTAMERIC 9-(2-DIMETHYLAMINOMETHYL-6-METHYLPHENYL)FLUORENE
Authors: Nakamura Mikio , Oki Michinori
Published: July 2006

The pKa′ values of the conjugate acids of the title compound were determined as 5.85 and 6.45, respectively, for the sp and ap isomers by potentiometric titration in THF-water solutions. The difference was ascribed to the existence of N–H···π interactions in the ap rotamer on the basis of the equilibrium constants between and barriers to rotation in rotamers of the conjugate acids and the free bases.
EOSIN Y SENSITIZED REDUCTION OF QUINONES TO THEIR PERSISTENT RADICAL ANIONS
Authors: Misawa Hiroaki , Wakisaka Akihiro , Sakuragi Hirochika , Tokumaru Katsumi
Published: July 2006

Eosin Y sensitized efficiently the reduction of duroquinone and anthraquinone-2-sulfonate to their persistent radical anions in aqueous 2-propanol in the presence of triethanolamine.
GLUCOSYLATION USING GLUCOPYRANOSYL DIMETHYLPHOSPHINOTHIOATE
Authors: Inazu Toshiyuki , Hosokawa Hideaki , Satoh Yuzuru
Published: July 2006

Several glucosides were prepared in good yields from 2,3,4,6-tetra-o -benzyl-α-d-glucopyranosyl dimethylphosphinothioate and alcohols in the presence of silver perchlorate. By this method α-glucosides were predominantly obtained.
AN APPLICATION OF 1H NMR TO THE DETERMINATION OF THE STOICHIOMETRY OF CROWN ETHER COMPLEXES (MLn (n=1,2): M=Li, Na, K, Rb, Cs, Ca, Sr, AND Ba; L=12-CROWN-4, 15-CROWN-5, AND 18-CROWN-6)
Authors: Iwachido Tadashi , Shibuya Koichi , Tôei Kyoj
Published: July 2006

Alkali and alkaline earth metal salts with 2,2′,4,4′,6,6′-hexanitrodiphenylamine were titrated stepwise with the crown ethers in nitrobenzene-d5 in the presence of a small quantity of water. The 1H NMR spectra obtained for each step showed that the water and the ligand signals shift on complexation. The stoichiometries of the crown ether complexes were obtained through analysis of the shift. The water signal was found to be advantageous to the stoichiometry determination for its high sensitivity.
FORMATION OF 10b,10c-DIHYDRO-10b,10c-DIMETHYLPYRENES IN REACTION OF 8,16-DIMETHYL[2.2]METACYCLOPHAN-1-ENES WITH PROTONIC ACIDS
Authors: Tashiro Masashi , Kobayashi Kazumasa , Yamato Takehiko
Published: July 2006

Reaction of 8,16-dimethyl[2.2]metacyclophan-1-enes with protonic acids such as 57% hydroiodic acid and trifluoroacetic acid afforded the corresponding 10b,10c-dihydro-10b,10c-dimethylpyrenes. Similar reaction with 47% hydrobromic acid and 36% hydrochloric acid gave surprisingly halogenated 10b,10c-dihydro-10b,10c-dimethylpyrenes.
A NEW PHOSPHORYLATING AGENT, 2,6-DICHLOROPHENYL 5-CHLORO-8-QUINOLYL PHOSPHOROCHLORIDATE. ITS APPLICATION IN DEOXYRIBOOLIGO-NUCLEOTIDE SYNTHESIS BY THE PHOSPHOTRIESTER APPROACH
Authors: Tsuchiya Hiromichi , Ueda Souichi , Kobayashi Hitoshi , Takaku Hiroshi
Published: July 2006

The mononucleotide units (4) was prepared by the action of 2,6-dichlorophenyl 5-chloro-8-quinolyl phosphorochloridate on nucleosides. 2,6-Dichlorophenyl group in the mononucleotide units (4) have been employed as a protecting group for 3′-terminal phosphodiester functions; it is stable under standard operations required for the deoxyribooligonucleotide synthesis and readily removed by the action of t-BuNH2 in pyridine-H2O within 90 min at room temperature.
SYNTHESIS OF METHYL (−)-SHIKIMATE FROM d-LYXOSE
Authors: Suami Tetsuo , Tadano Kin-ichi , Ueno Yoshihide , Iimura Youichi
Published: July 2006

Natural methyl (−)-shikimate has been synthesized from d-lyxose, employing a double carbon–carbon bond formation of 2,3,4-tri-O-benzyl-5-O-mesyl-d-lyxose with a dianion of dimethyl malonate as a key reaction.
FIRM EVIDNCE FOR CIS-AMINOPALLADATION IN THE REACTION OF 1-AMINOHEXATRIENES WITH PALLADIUM DICHLORIDE
Authors: Isomura Kazuaki , Okada Noriyuki , Saruwatari Masumi , Yamasaki Hirotaka , Taniguchi Hiroshi
Published: July 2006

The reaction of PdCl2(PhCN)2 with ethyl α-N-acetyl-β-(4,6-dimethylbenzofuran-2-yl)acrylate, having a Z-propenyl group at 2-position of benzofuran ring, gave an azepine derivative, whereas its E-isomer afforded a Pd-σ-complex having azepine skeleton. Configurational assignment of the σ-complex, accomplished by methoxycarbonylation, clearly demonstrates that this intramolecular aminopalladation proceeds via cis-aminopalladation.
DEPTH RESOLVED THERMAL WAVE IMAGING OF LAYER-STRUCTURED SAMPLE BY CORRELATION PHOTOACOUSTICS
Authors: Sugitani Yoshinori , Uejima Akinori
Published: July 2006

A new photoacoustic method, correlation photoacoustic imaging, has been developed combining two independently developed techniques, thermal wave imaging and correlation photoacoustic spectroscopy. This method can be used for surface and/or depth analysis of solid samples and was demonstrated on a layer-structured model sample.
THE ELECTROCHEMICAL REDUCTION OF CO2 CATALYZED BY RUTHENIUM CARBONYL COMPLEXES
Authors: Ishida Hitoshi , Tanaka Koji , Tanaka Toshio
Published: July 2006

The catalytic reduction of CO2 has been succesfully performed under the controlled potential electrolysis of [Ru (bpy)2 (CO)2](PF6)2 (bpy=2,2′-bipyridine) in a CO2-saturated H2O/DMF solution. Formic acid and CO as well as H2 are formed in alkaline conditions, while only CO and H2 are evolved in acidic conditions.
ACYCLIC STEREOSELECTION USING RELATIVE 1,2-ASYMMETRIC INDUCTION. SELECTIVE SYNTHESIS OF (+)-BLASTMYCINONE
Authors: Uchiyama Hiroshi , Kobayashi Yuichi , Sato Fumie
Published: July 2006

(+)-Blastmycinone has been synthesized based on the stereoselective addition reaction of 1-trimethylsilylvinylmagnesium bromide with (−)-(R)-2-butyl-3-trimethylsilylbut-3-enal.
STEREOSELECTIVE SYNTHESIS OF NATURAL (4S,6S,7S)-SERRICORNIN STARTING WITH (3S,4S)-4-HYDROXY-3-METHYL-1-HEXENE
Authors: Takeda Yoshiyuki , Kobayashi Yuichi , Sato Fumie
Published: July 2006

(4S,6S,7S)-Serricornin has been synthesized in three steps starting with (3S,4S)-4-hydroxy-3-methyl-1-hexene.
A FACILE PREPARATION OF ECDYSONE SIDE CHAIN BY UTILIZING FURAN DERIVATIVE
Authors: Kametani Tetsuji , Katoh Tadashi , Tsubuki Masayoshi , Honda Toshio
Published: July 2006

Construction of the ecdysone side chain starting from pregnenolone was achieved via a furan derivative. Reduction of the olefinic-furan over palladium–carbon afforded the hydrogenated furan derivative with the desired stereochemistry at C-20, exclusively, whose subsequent reduction over rhodium–alumina, followed by ruthenium tetroxide oxidation, gave the lactones in a ratio of ca. 1:1. Grignard reaction of both lactones with methylmagnesium bromide led to the synthesis of the triols having ecdysone-type side chains, respectively.
FLUORESCENCE QUENCHING IN HOST–GUEST COMPLEXES OF MODIFIED γ-CYCLODEXTRIN
Authors: Ueno Akihiko , Moriwaki Fumio , Tomita Yoko , Osa Tetsuo
Published: July 2006

Fluorescence quenching by guest ketones occurs in the complexes of γ-cyclodextrin appended by a naphthyl moiety, demonstrating the multifunctional behavior of the appended moiety that the moiety acts as both spacer and antenna of photoenergy.
OXYGENATION OF 4-ALKYNYL-2,6-DI-t-BUTYLPHENOLS
Authors: Nishinaga Akira , Iwasaki Hitoshi , Kondo Toshiyuki , Matsuura Teruo
Published: July 2006

The oxygenation of 4-alkynyl-2,6-di-t-butylphenols (1) promoted by Co(Salpr) resulted in the dioxygen incorporation predominantly into the side chain, whereas in the oxygenation of 1 with t-BuOK in t-BuOH dioxygen was incorporated exclusively into the ortho position. The results are rationalized by a radical process in the former reaction and a nonradical process in the latter oxygenation.
PROTONIC CONDUCTIVITY OF ALKALINE-EARTH METAL 12-TUNGSTOPHOSPHATES IN RELATION TO THEIR CATALYTIC ACTIVITY AS SOLID ACIDS
Authors: Akimoto Masamichi , Okamoto Masahide , Niiyama Hiroo
Published: July 2006

The protonic conductivity of alkaline-earth metal 12-tungstophosphates at solid state correlated their catalytic activity as solid acids for vapor-phase dehydration of ethanol.
PREPARATIONS OF TiO2-ATTACHED Rh CATALYSTS AND THEIR CATALYSIS
Authors: Iwasawa Yasuhiro , Sato Hiroko
Published: July 2006

New TiO2-attached Rh catalysts with the surface structures, (Remark: Graphics omitted.) Rh-C3H5(νC-H=3050 cm−1, νC-C=1462 cm−1), (Remark: Graphics omitted.) Rh-H(νRH=2048 cm−1) and (Remark: Graphics omitted.) [Rh]n(\barDn=1.4 nm, Rh-Rh=0.262 nm), were prepared by the reaction between Rh(η3-C3H5)3 and surface OH groups of TiO2, followed by chemical treatments with H2 . These catalysts showed higher activities for ethane hydrogenolysis and ethene hydrogena-tion than a conventional impregnation Rh catalyst.
THE CINNAMYLOXYCARBONYL GROUP AS A NEW AMINO-PROTECTING GROUP
Authors: Kinoshita Hideki , Inomata Katsuhiko , Kameda Takuo , Kotake Hiroshi
Published: July 2006

A new urethane-type protecting group for amines, cinnamyloxycarbonyl (Coc) group, is described. The cleavage of the Coc group is effectively catalyzed by 5 mol% of [Pd(PPh3)4] in the presence of formic acid, pyridine, and N-hydroxysuccinimide in refluxing THF. The Z- and Boc-protecting groups are not affected under the same reaction conditions.
FACILE SYNTHESIS OF FOUR ISOMERS OF LINEAR TENTOXIN SEQUENCE BY USING N-CARBOXY DEHYDROPHENYLALANINE ANHYDRIDE
Authors: Shin Chung-gi , Yonezawa Yasuchika
Published: July 2006

Four isomers of protected dehydrotetrapeptides of linear tentoxin sequence, consisted of Gly, Ala, Leu, and ΔPhe residues, were readily synthesized by using N-carboxy dehydrophenylalanine anhydride.
NEW FLAVIN SEMIQUINONE RADICALS AS PRODUCED BY THE REACTION WITH NADH MODEL COMPOUNDS
Authors: Shinkai Seiji , Honda Noriaki , Ishikawa Yuichi , Müller Franz , Manabe Osamu
Published: July 2006

The oxidation activity of a flavin (PyFl) with a fused pyridine moiety as a metal-chelation site was enhanced in the presence of certain metal ions. The reaction of PyFl and 1-benzyl-1,4-dihydronicotinamide in the presence of Mg(II), Zn(II), and Cd(II) in acetonitrile gave a transient absorption band at around 500 nm and an ESR spectrum attributable to the semiquinone radical. This is the first example for the flavin semiquinone radical produced by the reaction with an NADH model compound.
PREPARATION OF TRIS(3-SUBSTITUTED ACETYLACETONATO)RUTHENIUM(III) COMPLEXES AND THEIR ELECTROCHEMICAL BEHAVIOR IN ACETONITRILE
Authors: Endo Akira , Shimizu Kunio , Satô Gen P
Published: July 2006

Four tris(3-substituted acetylacetonato)ruthenium(III) complexes were newly synthesized and their electrochemical oxidation and reduction were investigated in acetonitrile. The oxidation and reduction potentials of [RuIII(R′-CO-CR-CO-R″)-] can be expressed as a linear function of the sum of the Hammett constants, if one uses the para-position value for R and the meta-position values for R′ and R″.
SYNTHESIS OF α-AMINO KETONES FROM α,β-EPOXY SULFOXIDES
Authors: Satoh Tsuyoshi , Kaneko Youhei , Sakata Kiichi , Yamakawa Koji
Published: July 2006

Various kinds of α-amino ketones and α-arylamino ketones are synthesized in good yields by aminolysis of α,β-epoxy sulfoxides which are easily prepared from alkylated chloromethyl phenyl sulfoxide and carbonyl compounds.
ALCOHOL SYNTHESIS FROM CO2/H2 ON SILICA-SUPPORTED MOLYBDENUM CATALYSTS
Authors: Tatsumi Takashi , Muramats Atsushi , Tominaga Hiro-o
Published: July 2006

In the hydrogenation of CO2 over alkali-promoted Mo/SiO2 catalysts, C1–C5 alcohols were selectively obtained at 16 kg/cm2 and 250 °C.
PHOTOCHEMICAL REACTION OF 2-ALKENOYL-1,4-QUINONES. FORMATION OF CHROMONE DERIVATIVES
Authors: Maruyama Kazuhiro , Iwamoto Hidetoshi , Soga Osamu , Takuwa Akio , Osuka Atsuhiro
Published: July 2006

Irradiation of 5-methyl-2-(α-methylalkenoyl)-1,4-benzoquinones in alcohol under anaerobic conditions gave the two isomers of chromone derivatives being isomerization products of the quinones. Besides them other two adducts were produced. The mechanism of formation of these products is discussed.
MANGANESE-MEDIATED ALLYL ADDITION TO ENOLIZABLE ALDEHYDE AND KETONES. AN APPROACH FOR INTRODUCTION OF ACETONYL SIDE CHAIN AT C(9) OF ANTHRACYCLINE ANTIBIOTICS
Authors: Hiyama Tamejiro , Sawahara Miwa , Kusano Yukari
Published: July 2006

Allyl addition to enolizable aldehyde and ketones is achieved efficiently with manganese reagents generated by the reaction of allyl bromide with MnCl2–LiAlH4 or Mn powder. The Wacker oxidation of the β-tetralone adducts gives an acetonyl moiety typical to an anti-tumor antibiotic, feudomycin.
ACID CATALYZED REDUCTION OF NITROSOBENZENE IN WATER BY 1-BENZYL-3,5-DIPYRROLIDINOCARBAMOYL-1,4-DIHYDROPYRIDINE AS A NADH ANALOG
Authors: Awano Hiroshi , Tagaki Waichiro
Published: July 2006

Acid catalysis has been observed for the reduction of substituted nitrosobenzenes in water by an acid stable NADH analog, 1-benzyl-3,5-dipyrrolidinocarbamoyl-1,4-dihydropyridine.
CARBON-SULFUR BOND CLEAVAGE BY BENZYNE GENERATED FROM 2-CARBOXYBENZENEDIAZONIUM CHLORIDE
Authors: Nakayama Juzo , Hoshino Keiichi , Hoshino Masamatsu
Published: July 2006

The reaction of cyclic sulfides with benzyne generated from 2-carboxybenzenediazonium chloride affords ω-chloroalkyl phenyl sulfides in good yields. A similar type of reaction was also observed with acyclic sulfides.
PREPARATION OF 7,7,8,8-TETRACYANOQUINODIMETHANE AND ITS DERIVATIVES
Authors: Yamaguchi Shunro , Hanafusa Terukiyo
Published: July 2006

The reaction of terephthaloyl chloride with cyanotrimethylsilane in the presence of pyridine gave 1,4-bis(dicyanotrimethylsiloxymethyl)benzene, which was treated with POCl3-pyridine to afford tetracyanoquinodimethane (TCNQ) along with its dichloride. Similarly, 2,5-dimethyl-TCNQ and 2-bromo-TCNQ were prepared from the corresponding terephthaloyl chlorides.
14N NUCLEAR QUADRUPOLE SPLITTINGS OF PHOSPHATIDYLCHOLINE IN BILAYERS. THE INFLUENCE OF NEGATIVE CHARGE IN THE HEAD GROUPS
Authors: Kanazawa Yoko , Takano Ritsuko , Nishizono Isao , Koga Keiko , Ishikawa Makoto , Higuchi Wakako , Yamada Toru
Published: July 2006

The 14N nuclear quadrupole splitting of phosphatidylcholine was measured in the presence of acidic lipids in multibilayers. The splitting was found to increase with negative charge in mixed lipid systems.
SYNTHESIS OF SWEET TASTING PSEUDO-β-FRUCTOPYRANOSE
Authors: Suami Tetsuo , Ogawa Seiichiro , Takata Makoto , Yasuda Kuninobu , Suga Atsuo , Takei Kiyoshi , Uematsu Yasushi
Published: July 2006

Pseudo-β-Dl-fructopyranose has been synthesized from Dl-1,2-di-O-acetyl-(1,3/2)-3-bromomethyl-5-cyclohexene-1,2-diol by two reaction routes. The pseudosugar was found to be sweet and this fact provides a strong support for Shallenberger’s sweetness-structure hypothesis.
INTERMEDIACY OF CHARGED SPECIES IN PHOTODECOMPOSITION OF DIAROYL PEROXIDES SENSITIZED WITH AROMATIC HYDROCARBONS IN POLAR SOLVENTS
Authors: Urano Toshiyuki , Sakuragi Hirochika , Tokumaru Katsumi
Published: July 2006

Electron transfer upon photosensitization of dibenzoyl and bis (2-thiophenecarbonyl) peroxides with singlet sensitizers in acetonitrile was revealed by trapping of sensitizer (naphthalene) cation radicals with acetic acid and by their direct detection (pyrene cation radicals) by means of laser flash photolysis.
ECKOLS, NOVEL PHLOROTANNINS WITH A DIBENZO-p-DIOXIN SKELETON POSSESSING INHIBITORY EFFECTS ON α2-MACROGLOBULIN FROM THE BROWN ALGA ECKLONIA KUROME OKAMURA
Authors: Fukuyama Yoshiyasu , Miura Iwao , Kinzyo Ziunei , Mori Hideo , Kido Masaru , Nakayama Yasuo , Takahashi Masayuki , Ochi Masamitsu
Published: July 2006

Eckol, 2-phloroeckol and dieckol, novel phlorotannins with a dibenzo-p-dioxin skeleton have been isolated from the brown alga Ecklonia kurome Okamura as plasma α2-macroglobulin inhibitors and their structures have been determined on the basis of spectral data, in particular, by means of negative NOEs.
DRASTIC EFFECT OF CROWN-COMPLEXING CATION IN REVERSED-PHASE LIQUID CHROMATOGRAPHY USING POLY(CROWN ETHER)-IMMOBILIZED SILICA
Authors: Kimura Keiichi , Harino Hiroya , Nakajima Masaki , Shono Toshiyuki
Published: July 2006

A poly(crown ether)-immobilized silica behaves as a stationary phase for reversed-phase liquid chromatography as well as ion chromatography. The retention of several polar organic solutes in the reversed-phase liquid chromatography can be controlled easily by addition of alkali metal salts to the mobile phase, owing to electrostatic interaction between the solutes and the metal ion complexed by the crown ether moiety on the stationary phase.
ON THE DIFFERENCE IN REACTION PATHWAYS OF STEAM REFORMING OF METHANOL OVER COPPER-SILICA AND PLATINUM-SILICA CATALYSTS
Authors: Takahashi Kazunari , Kobayashi Haruo , Takezawa Nobutsune
Published: July 2006

Steam reforming of methanol CH3OH + H2O\ightharpoonupCO2 + 3H2 proceeded through different pathways over copper-silica and platinum-silica catalysts. This was ascribed to the difference in the reactivities of formaldehyde intermediates formed in the reaction over these catalysts.
PHOTOISOMERIZATION OF 1-METHOXYPHENAZINE-N,N-DIOXIDE IN PROTIC AND APROTIC SOLVENTS
Authors: Kawata Hiroki , Niizuma Shigeya , Kumagai Tsutomu , Kokubun Hiroshi
Published: July 2006

Photoisomerization of 1-methoxyphenazine-N,N-dioxide was investigated in protic and aprotic solvents. It showed photochromism in aprotic solvents. In protic solvents, irreversible photoisomerization occurred and the photoproduct was identified to be the methoxyl derivatives of oxepinoquinoxaline N-oxide.
DIRECT SYNTHESIS OF ISOPARAFFINS FROM SYNTHESIS GAS
Authors: Fujimoto Kaoru , Adachi Michiaki , Tominaga Hiro-o
Published: July 2006

The product distribution of Fischer–Tropsch synthesis was drastically improved by utilizing hybrid catalysts prepared by combining F-T catalysts such as cobalt, iron and ruthenium catalysts with metal supported Y zeolite while keeping high activities. About 80% of the product was C4-11 hydrocarbons, most of which were isoparaffins.
HYDROGENATION OF OLEFINS WITH CATIONIC RHODIUM COMPLEX INTERCALATED IN FLUORO TETRASILICI\'{C} MICA
Authors: Miyazaki Takayuki , Tsuboi Akio , Urata Hisao , Suzuki Hiroharu , Morikawa Yutaka , Moro-Oka Yoshihiko , Ikawa Tsuneo
Published: July 2006

The hydrogenation of olefins was studied with a Rh complex catalyst intercalated in a synthetic mica. Steric influence due to the interlayers on the hydrogenation rate is observed not with aliphatic olefins but with cycloolefins. The intercalated catalyst shows enhanced selectivity relative to the homogeneous catalyst in the hydrogenation of 4-vinylcyclohexene.
STEREOSELECTIVE SYNTHESIS OF CIS-α,β-EPOXYESTERS AND ALDEHYDES VIA DIVALENT TIN ENOLATE. A SYNTHESIS OF 2-AMINO-2-DEOXY-d-ARABINITOL
Authors: Mukaiyama Teruaki , Yura Takeshi , Iwasawa Nobuharu
Published: July 2006

A convenient method for the stereoselective synthesis of cis-α,β-epoxyesters and aldehydes is established according to the Sn(OTf)2 mediated cross aldol reaction between α-bromo-α′-silyloxyketone and aldehyde. The reaction is applied to the stereoselective synthesis of 2-amino-2-deoxy-d-arabinitol.
ASYMMETRIC REDUCTION OF PROCHIRAL KETO ESTERS WITH A CHIRAL REDUCING AGENT PREPARED FROM TIN(II) CHLORIDE, CHIRAL DIAMINE, AND DIISOBUTYLALUMINUM HYDRIDE
Authors: Mukaiyama Teruaki , Tomimori Koji , Oriyama Takeshi
Published: July 2006

Asymmetric reduction of prochiral keto esters with a reagent, generated by treatment of a mixture of tin(II) chloride and a chiral diamine derived from (S)-proline with diisobutylaluminum hydride, afforded the corresponding optically active hydroxy esters.
CONFORMATIONAL CHARACTERIZATION OF BIOLOGICALLY ACTIVE PEPTIDES, PRO-LEU-GLY-NH2 AND GRAMICIDIN S, IN THE SOLID AND SOLUTION AS REVEALED BY CONFORMATION-DEPENDENT 13C CHEMICAL SHIFTS
Authors: Saitô Hazime , Tabeta Ryoko
Published: July 2006

13C NMR spectra of biologically active peptides, Pro-Leu-Gly-NH2 and gramicidin S, in the solid state were compared with those in solution, to gain insight of stability of the β-turn structure in the former in solution and of conformational feature of the latter in the solid state.
PHOTOELECTROCHEMICAL CELL USING SiC FOR WATER SPLITTING
Authors: Inoue Tooru , Yamase Toshihiro
Published: July 2006

Photoelectrochemical cell using silicon carbide and Pt electrodes can split water into H2 and O2 without any external bias. Maximum photovoltage was ca. 0.45 V for a
 photocell and 2.2V for a
 photocell. Energy conversion efficiency to H2 was ca. 0.4% for irradiation with a 500 W Xe lamp.
SELECTIVE SYNTHESIS OF ETHANOL OVER Rh–Ti–Fe–Ir/SiO2 CATALYST AT HIGH PRESSURE SYNGAS CONVERSION
Authors: Arakawa Hironori , Fukushima Takakazu , Ichikawa Masaru , Natsushita Shoshiro , Takeuchi Kazuhiko , Matsuzaki Takehiko , Sugi Yoshihiro
Published: July 2006

A high performance catalyst for ethanol production -has been developed. Ethanol was produced with more than 50% selectivity from syngas over Rh–Ti–Fe–Ir/SiO2 under the condition of 50 atm and 260 °C. The roles of additives were discussed from the point of the reaction behavior and physical property of this catalyst.
OPTICAL RESOLUTION OF KEY COMPOUNDS OF PROSTAGLANDIN SYNTHESIS AND RELATED COMPOUNDS
Authors: Toda Fumio , Tanaka Koichi
Published: July 2006

Hundred per cent optically pure bicyclic lactones and bicyclic ketones were easily obtained By complexation method with optically active 1,6-bis(2-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol.
MECHANISTIC INVESTIGATION OF DISTANNOXANE-CATALYZED URETHANE FORMATION STUDIED By 119Sn NMR SPECTRA
Authors: Otera Junzo , Yano Toru , Okawara Rokuro
Published: July 2006

The mechanism of urethane formation catalyzed By tetraorganodistannoxanes was investigated. The 119Sn NMR spectra and the model reaction between methanol and phenyl isocyanate revealed that the formation of the alkoxy distannoxanes is the initial step.
OXYGENATION OF COBALT(II) SCHIFF BASE COMPLEXES IN ALCOHOLS
Authors: Nishinaga Akira , Kondo Toshiyuki , Matsuura Teruo
Published: July 2006

The oxygenation of cobalt(II) Schiff base complexes in alcohols resulted in irreversible oxidation to give the corresponding alcoholatocobalt(III) complexes, which were converted to hydroxocobalt(III) species By treatment with water. Kinetic studies on the oxidation suggest a mechanism involving rate determining proton transfer from alcohols to cobalt-dioxygen adducts.
ENHANCEMENT OF HUMIDITY SENSITIVITY FOR PEROVSKITE-TYPE OXIDES HAVING SEMICONDUCTIVITY
Authors: Shimizu Yasuhiro , Shimabukuro Muneharu , Arai Hiromichi , Seiyama Tetsuro
Published: July 2006

The humidity sensitivities of SrSnO3 and BaSnO3 were enhanced slightly By means of calcining their hydroxides, which were prepared by a coprecipitation method. The partial substitution of the A site element of the perovskite-type oxides with lanthanum was more useful for the enhancement of the sensitivity. The highest sensitivity was found in Sr0.95La0.05SnO3 among the specimens studied.
ELECTROPHILIC REACTION OF ALLYLTRIMETHYLSILANE WITH NITRILES IN THE PRESENCE OF BORON TRICHLORIDE
Authors: Hamana Hiroshi , Sugasawa Tsutomu
Published: July 2006

Allyltrimethylsilane reacted with various nitriles in the presence of boron trichloride, giving after hydrolysis β,γ-unsaturated ketones in high yields. The reactions of substituted allyltrimethylsilanes and intramolecular reaction of allylic trimethylsilane with nitrile were also studied.
THE EFFECT OF SOLVENT ON THERMAL CRACKING OF BIBENZYL AS A COAL MODEL
Authors: Chiba Koji , Tagaya Hideyuki , Yamauchi Taku , Thukahara Yoshitaro
Published: July 2006

The effect of solvent on bibenzyl conversion depends on the nature of solvent. Triphenylmethane, diphenylmethane, and diphenylamine are poor hydrogen donor solvents. But, when these compounds were used as solvent, bibenzyl conversion was markedly enhanced, and toluene, stilbene and adducts were formed. Moreover, when a proper amount of tetralin was mixed with the above solvent, toluene was solely obtained in reasonable yield.
A CONVENIENT PROCEDURE FOR THE PREPARATION OF DINUCLEOSIDE PHOSPHATES By THE USE OF A BIFUNCTIONAL PHOSPHORYLATING REAGENTS, 2-CHLOROPHENYLPHOSPHOROBIS(NITROBENZOTRIAZOLIDE)
Authors: Mitsunobu Oyo , Takahashi Miyako , Seki Hiroshi , Arai Makoto , Yasumoto Fumiko , Iwami Hideaki , Kawakami Naoto , Kamishiro Junko
Published: July 2006

The reagent formed By the reaction of 2-chlorophenyl phosphorodichloridate with 2 molar amounts of 5-nitrobenzotriazole was allowed to react successively with nucleosides having free 3′-hydroxyl groups and nucleosides having free 5′-hydroxyl groups affording the corresponding dinucleoside phosphates in 63–97% yields.
THE TRITYL PERCHLORATE CATALYZED MICHAEL REACTION
Authors: Kobayashi Shu , Murakami Masahiro , Mukaiyama Teruaki
Published: July 2006

In the presence of a catalytic amount of trityl perchlorate, 1,5-dicarbonyl compounds, the Michael adducts, are obtained in high yields by the reaction of silyl enol ethers with α,β-unsaturated ketones. The intermediate adducts, the synthetically valuable silyl enol ethers, are also isolated in high yields.
CRYSTAL STRUCTURE AND PROPERTIES OF THE DBTTF SALT WITH A NOVEL CHLORIDE-BRIDGED TRIMERIZED DIMETHYLTIN(IV) DIANION. [DBTTF]3[Sn3(CH3)6Cl8]·C6H5CN
Authors: Matsubayashi Gen-etsu , Shimizu Ryuichi , Tanaka Toshio
Published: July 2006

The title salt has been obtained By electrolysis of dibenzotetrathiafulvalene in a benzonitrile solution containing dichlorodimethyltin(IV) and benzyltriphenylphosphonium chloride. The X-ray crystal analysis has revealed the presence of a DBTTF columnar structure and a novel trimerized tin(IV) anion [Sn3(CH3)6Cl8]2−. Electrical and spectroscopic properties also are described.
A FACILE SYNTHESIS OF HOMOALLYL ETHERS. THE REACTION OF ACETALS WITH ALLYLTRIMETHYLSILANES PROMOTED BY TRITYL PERCHLORATE OR DIPHENYLBORYL TRIFLATE
Authors: Mukaiyama Teruaki , Nagaoka Hitoshi , Murakami Masahiro , Ohshima Masahiro
Published: July 2006

In the presence of a catalytic amount of trityl perchlorate or diphenylboryl triflate, acetals react smoothly with allyltrimethylsilanes to give the corresponding homoallyl ethers in good yields with good regio- and stereoselectivities.
DETERMINATION OF RARE EARTH ELEMENTS IN GEOLOGICAL STANDARD ROCK SAMPLES BY INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROMETRY
Authors: Toyoda Kazuhiro , Haraguchi Hiroki
Published: July 2006

Rare earth elements in the standard rock samples such as GSJ JG-1, GSJ JB-1, and USGS AGV-1 have been determined simultaneously by inductively coupled plasma atomic emission spectrometry. It has been found that heavy rare earth elements in JG-1 provide lower values when it is dissolved by the acid digestion method.
REVERSIBLE TRANSPHOSPHORYLATION AMONG ATP, ADP, AND AMP IN THE PRESENCE OF METHYLATED CYCLODEXTRIN
Authors: Hattori Kenjiro , Takahashi Keiko
Published: July 2006

A transphosphorylation among AMP, ADP, and ATP in a neutral aqueous solution with MgCl2 was examined in the presence of heptakis-(2,6-dimethyl)-β-cyclodextrin or heptakis-(2,3,6-trimethyl)-β-cyclodextrin. Adding methylated cyclodextrins was found to facilitate both forward and reversed reaction according to Eq.2 with an equilibrium constant of approximate unity.
LIQUID HOLDUP OF FOAM AS AN INDEX FOR MECHANICAL FOAM-CONTROL IN GAS-LIQUID CONTACTOR
Authors: Ohkawa Akira , Ueda Yasuyuki , Sakai Nobuyuki
Published: July 2006

Liquid holdup of foam generated in a gas-liquid contactor was measured under mechanical foam control with a rotating disk foam-breaker(MFRD), The results showed that liquid holdup of foam not only is an index of dynamic foaming state of the contactor but also provides a good measure for effective operation of MFRD.
NOVEL HYDROXYMETHYLATION OF ARYL BROMIDES BY MEANS OF ORGANOTIN REAGENTS
Authors: Kosugi Masanori , Sumiya Takashi , Ohhashi Kenji , Sano Hiroshi , Migita Toshihiko
Published: July 2006

Direct transformation of aryl bromides to benzylic alcohols by means of hydroxymethyltributyltin in the presence of palladium complex was attained in moderate yields, although the catalytic efficiencies were rather low, and the reaction could not be applied to aryl bromides having strong electron-withdrawing group. These problems were solved by using the trimethylsilyl-protected tin compound.
CRYSTAL AND BAND STRUCTURES OF AN ORGANIC CONDUCTOR β″-(BEDT-TTF)2AuBr2
Authors: Mori Takehiko , Sakai Fumiko , Saito Gunzi , Inokuchi Hiroo
Published: July 2006

A novel organic conductor β″-(BEDT-TTF)2AuBr2 (BEDT-TTF: bis(ethylenedithio)tetrathiafulvalene, C10H8S8) crystallizes in the triclinic space group p\bar1, with cell constants: a=9.027(1), b=16.372(2), c=5.712(1) Å, α=97.60(1), β=102.94(1), γ=92.09(1) °, V=813.7(2) Å3, and Z=1. A band structure calculation indicates that its intermolecular interaction is largest along the transverse molecular array.
Electrochemical Preparation of a Chelating Polymer-modified Electrode for Selective Incorporation of Ag(I)
Authors: Egashira Naoyoshi , Kudo Masanao , Hori Fumiaki
Published: July 2006

The electrode modified with styrene-divinylbenzene copolymer containing–N(CH2CO2H) has been prepared electrochemically on a glassy carbon rod, and applied to the selective incorporation of Ag(I) from aqueous solutions.
Synthesis of 2-Acetamido-1,5-imino-1,2,5-trideoxy-d-mannitol and of 2-Acetamido-1,5-imino-1,2,5-trideoxy-d-glucitol, a Potent and Specific Inhibitor of a Number of β-N-Acetylglucosaminidases
Authors: Fleet George W J , Smith Paul W , Nash Robert J , Fellows Linda E , Parekh Raj B , Rademacher Thomas W
Published: July 2006

The stereochemical outcome of the azide displacement of triflates derived from a piperidin-3-ol depends on the protecting group on the ring nitrogen and allows the synthesis of 2-acetamido-1,5-imino-1,2,5-trideoxy-d-glucitol (a potent and specific inhibitor of a number of β-N-acetylglucosaminidases) and of 2-acetamido-1,5-imino-1,2,5-trideoxy-d-mannitol.
INTERACTION OF ORGANOTRANSITION METALS WITH NUCLEOSIDES. PREPARATION AND PROPERTIES OF METHYL(1,5-CYCLOOCTADIENE)(NUCLEOSIDE)PLATINUM(II)+
Authors: Komiya Sanshiro , Mizuno Yuuko , Shibuya Tomohiro
Published: July 2006

Organoplatinum(II) complexes having nucleoside(Nuc) as a ligand, [PtMe(COD)(Nuc)]+ (Nuc=Guo, Cyd, Ado) have been prepared by the reaction of PtMeCl(COD) with nucleoside in the presence of AgNO3. The 1H-NMR study of the competitive equilibrium of various nucleosides reveals the high selective binding of Guo and Cyd to the organoplatinum(II) center.
Direct Observation of Aromatic Anion Radicals as Intermediates in the Reactions of Aromatic Compound Vapors with Calcium Atom
Authors: Mochida Kunio , Mizuno Yasuhisa
Published: July 2006

Aromatic anion radicals as intermediates in the reactions of aromatic compound vapors with calcium atom were directly observed by ESR.
Crystal and Solution Structures of Nickel(II)-13-Membered Macrocyclic Tetramine [1,4,7,10-Tetraazacyclotridecanenickel(II)] Effected by a Pendent Phenol
Authors: Kimura Eiichi , Uenishi Keiji , Koike Tohru , Iitaka Yoichi
Published: July 2006

In crystal structure of NiII-phenol-pendent[13]aneN4 complex 3 the pendent phenolate coordinates to high-spin NiII in a folded[13]aneN4: in aqueous solution, the equilibrium of phenol\ightleftarrowsphenolate directly determines low-spin, square-planar or high-spin, folded macrocyclic structure.
Alkaline Hydrolysis Products of Ammonium Nitridotris(sulfate)
Authors: Masuda Etsuro
Published: July 2006

The products of the alkaline hydrolysis reaction of ammonium nitridotris(sulfate) were first identified as imidobis(sulfate) and sulfate by ion-exchange separation and infrared spectroscopy.
A Stereocontrolled Synthesis of 2,3,5-Trisubstituted Tetrahydrofurans from Aldolized γ-Diketones via Cyclization-reduction Process
Authors: Mukaiyama Teruaki , Hayashi Masaji , Ichikawa Junji
Published: July 2006

2,3,5-Trisubstituted tetrahydrofurans with cis-2,5 relationship are obtained in good yields by cyclization of the silyl ethers of aldolized γ-diketones followed by successive stereocontrolled reduction with triethylsilane in the presence of trityl perchlorate as a catalyst.
Synthesis and Crystal Structure of a Highly Conducting (Phthalocyaninato)nickel Hexafluoroantimonate, (NiPc)2SbF6
Authors: Yakushi Kyuya , Sakuda Makoto , Kuroda Haruo , Kawamoto Atsushi , Tanaka Jiro
Published: July 2006

Sigle crystals of a metallic (phthalocyaninato)nickel hexafluoro antimonate, (NiPc)2SbF6, were newly prepared by the use of an electrochemical technique. NiPc is stacked one-dimensionally in a slight zigzag way, which quite resembles the structure of highly conducting NiPcI.
Effects of Calcination and Reduction Temperatures upon Particle Size of Ni in Ni/SiO2 Catalyst Prepared by Alkoxide Technique
Authors: Tamagawa Hiroyuki , Oyama Kyuichi , Yamaguchi Tsuyoshi , Tsuiki Hideyasu , Ueno Akifumi
Published: July 2006

The particle size of Ni in Ni/SiO2 catalyst prepared by alkoxide technique was proved to be well controlled by setting proper calcination and reduction temperatures even for the constant nickel metal concentration in the catalyst.
Enantioselective Synthesis of the Functionalized Bicyclo[2.2.1]heptane Derivatives, Key Intermediates for the Chiral Synthesis of Santalenes and Santalols
Authors: Arai Yoshitsugu , Yamamoto Masatoshi , Koizumi Toru
Published: July 2006

Optically active functionalized bicyclo[2.2.1] heptane derivatives obtained by the asymmetric Diels–Alder cycloaddition of ethyl p-tolylsulfinylmethylenepropionate with cyclopentadiene provide the potentially useful intermediates for synthesis of bicyclic sesquiterpenes such as (+)-epi-β-santalene.
α-Diethoxyphosphinyl-γ-butenolide, a Versatile Reagent for the Synthesis of α,β-Difunctionalized γ-Lactones
Authors: Minami Toru , Kitajima Yoshiyuki , Chikugo Tsuguhiko
Published: July 2006

α-Diethoxyphosphinyl-γ-butenolide (2) was synthesized in good yield by phenylselenenylation of an α-diethoxyphosphinyl-γ-butyrolactone carbanion and subsequent oxidative elimination of the phenylseleno residue. The butenolide 2 underwent the Michael addition of various nucleophiles to generate the phosphoryl-stabilized carbanions, which reacted with carbonyl compounds to give α,β-difunctionalized γ-butyrolactones, lignans, and a γ-butyrolactohe annelated compound.
Electrochemical Behavior of Polypyrrole Deposited on Nafion-coated Electrodes
Authors: Yoneyama Hiroshi , Hirai Takayuki , Kuwabata Susumu , Ikeda Osamu
Published: July 2006

Anodic polymerization of pyrrole at Nafion-coated ITO or Au electrodes gives a polypyrrole-Nafion co-polymer film at the Nafion/electrode substrate interface. Sulfonate groups of Nafion and not the electrolyte anions are involved in the polymerization process. The redox reaction of the resulting polymer film occurs more easily than that of polypyrrole films prepared on the naked electrode substrate.
A New Polymorph of Hydroxyaluminum Phthalocyanine. Characterization and Photoactivity
Authors: Dao Lê H , Perrier Gérard
Published: July 2006

Sublimed films of α-form hydroxyaluminum phthalocyanine (α-PcAlOH) can be transformed into a novel polymorph by a treatment with aqueous acid solutions. The spectroscopic characterization of the new polymorph, showing its particular visible and IR spectra and X-ray diffraction pattern was achieved by comparing with other polymorphs. The dimorphic transformation of PcAlOH is also associated with a dramatic enhancement in photoactivity as shown in the performance of a photoelectrochemical cell based upon a PcAlOH/redox junction.
Stable Configuration of Ester-Stabilized Azomethine Ylides. Stabilization of anti-Form by 1,5-Dipolar Interaction and of syn-Form by Hydrogen Bonding
Authors: Tsuge Otohiko , Kanemasa Shuji , Ohe Masayuki , Yorozu Kiyotaka , Takenaka Shigeori , Ueno Kazunori
Published: July 2006

Stable configuration of ester-stabilized azomethine ylides is found to depend upon the substituent on the ylide nitrogen. Thus, N-substituted azomethine ylides derived from N-substituted 2-aminoacetates and carbonyl compounds undergo cycloaddition with olefinic dipolarophiles predominantly in anti forms, while N-protonated (or N-unsubstituted) azomethine ylides generated from 2-iminoacetates exclusively in syn forms.
Synthesis and Properties of Dicyanotrideca-, -pentadeca-, and -heptadecafulvene Derivatives
Authors: Ojima Juro , Ishizaka Shuichi , Shiraiwa Yasunao , Ejiri Emiko , Kato Tadahito , Kuroda Shigeyasu , Takeda Hideya
Published: July 2006

Title fulvenes were synthesized through the reaction of the large-membered annulenones with malononitrile, and their 1H NMR spectra were examined proving that the dicyanotrideca- and -heptadecafulvenes are paratropic while the dicyanopentadecafulvene is diatropic.
High-pressure Cycloaddition Reaction of Tropone with Furans
Authors: Sugiyama Shigeru , Tsuda Tohru , Mori Akira , Takeshita Hitoshi , Kodama Mitsuaki
Published: July 2006

Thermal reactions of tropone with furan and 2-methoxyfuran gave mainly the endo-[4+2] cycloadducts at 3000 bar. In the latter case, the products further reacted with tropone to yield 2:1-adducts. The NMR spectral data defined their stereochemistry; predominant formation of endo-adduct is rare in the Diels–Alder reaction of furans. This must be due to the conditions employed, under which the cycloreversion is prevented.
Oxidation of Thymines and Uracils with Sodium Peroxodisulfate
Authors: Itahara Toshio , Ebihara Reiko , Fujii Yukiko , Tada Miki
Published: July 2006

Reaction of thymines with Na2S2O8 in water resulted in selective oxidation of the methyl group at 5-position of thymines. Oxidation of thymines with Na2S2O8 in hydrochloric acid gave 5-chloro-6-hydroxy-5,6-dihydrothymines and in acetic acid containing NaCl gave 6-acetoxy-5-chloro-5,6-dihydrothymines which were converted to 6-alkoxy-5-chloro-5,6-dihydrothymines with alcohols. The reaction of uracils also gave similar products together with 5-chlorouracils.
Nickel-catalyzed Ring-opening Reactions of Epoxides and Their Regioselectivities
Authors: Miyashita Akira , Shimada Takeshi , Sugawara Atsushi , Nohira Hiroyuki
Published: July 2006

NiBr2(PPh3)2 catalyzed ring-opening isomerization of epoxides to yield the corresponding aldehydes exclusively, while Ni(PPh3)3 and NiBr2L2 (L= PMe2Ph, PEt3 and PCy3) were found to afford ketones, alcohols and olefins. Regioselectivity for a C–O bond cleavage of epoxides is determined by the nature of the ligand coordinated to the metal center.
Regioselective Ring-opening Reactions of 2,3-Epoxy Alcohols with Sodium Azide Supported on Zeolite CaY
Authors: Onaka Makoto , Sugita Keisuke , Izumi Yusuke
Published: July 2006

Sodium azide supported on zeolite CaY induces C-3 ring-opening of 2,3-epoxy alcohols to afford 3-azido-1,2-diols in much higher regioselectivity than a conventional reagent system of Na3–NH4Cl in MeOH–H2O. The cation in zeolite greatly influences the regioselectivity of the reaction.
Stereochemistry of Merolimonol by 1H NMR and CD Spectral Studies
Authors: Nakatani Munehiro , Iwashita Takashi , Naoki Hideo , Hase Tsunao
Published: July 2006

The stereochemistry of merolimonol was investigated by 1H NMR study including COSY and NOESY, and CD application to the benzoates confirmed the ring conformation.
Electrical Conductivity of HMTTeF Radical Salts
Authors: Matsuzaki Susumu , Li Zhu Shi , Sano Mizuka
Published: July 2006

Single crystals of HMTTeF·Xn ( X=Cl, Br, I, PF6, AsF6, and ClO4) were prepared by the electrochemical method. The in-plane conductivities of the plate-like chloride, bromide, and iodide crystals were found to show metallic temperature dependence in the range from 300 to ca. 100 K, and to maintain fairly high values even at 5 K. In these metallic salts, HMTTeF was found to be in the state of mixed-valency by Raman spectroscopy.
CONJUGATED HETEROCUMULENES. SYNTHESIS OF C=C-CONJUGATED CARBODIIMIDES BY A WITTIG-TYPE REACTION OF IMINOPHOSPHORANES WITH ISOCYANATES AND THEIR CYCLOADDITIONS
Authors: Saito Takao , Nakane Michio , Endo Masanobu , Yamashita Hiromi , Oyamada Yoko , Motoki Shinichi
Published: July 2006

A Wittig-type reaction of N-(1,2-diarylethenyl)iminophosphoranes with isocyanates gave C=C-conjugated carbodiimides, which were utilized in the synthesis of heterocycles.
[3,3]Claisen vs. [2,3]Wittig Shift in Thermal and Fluolide Ion-Promoted Rearrangements of the O- and C-Silylated Forms of α-Allyloxy Esters
Authors: Takahashi Osamu , Maeda Toshihiko , Mikami Koichi , Nakai Takeshi
Published: July 2006

Thermolysis of the O-silylated forms of α-allyloxy esters is shown to afford exclusively the [3,3]Claisen products with high stereocontrol. In direct contrast, the fluoride ion-promoted rearrangement of the α-silylated esters gives exclusively the [2,3]Wittig products with moderate stereocontrol.
A Facile Synthesis of Sulfides Using S-Aryl-isothiuronium Intermediates
Authors: Takagi Kentaro
Published: July 2006

A variety of sulfides were conveniently prepared by a treatment of aryl iodides with thiourea in the presence of a nickel(0) catalyst, then with CaO, and finally with a variety of electrophiles such as alkyl, acyl, silyl, aryl, or alkenyl halides.
Trifunctional Chiral Synthons via Stereocontrolled Yeast Reduction. Preparation of Chiral Pentane-1,3,5-triol Derivatives
Authors: Hirama Masahiro , Nakamine Takeshi , Itô Shô
Published: July 2006

Easy access to pentane-1,3,5-triol derivatives of high optical purity, trifunctional chiral synthons of fundamental importance in the synthesis of various natural products is described, as well as the stereocontrol of baker’s yeast reduction of 5-substituted 3-oxopentanoates.
Automerization of [4.2.2]Propella-2,4,7,9-tetraene. Intermediacy of a Cyclobutadiene Derivative and Its Trapping by Methanol
Authors: Tsuji Takashi , Nishida Shinya
Published: July 2006

Automerization of (4.2.2)propella-2,4,7,9-tetraene system proceeds via a cyclobutadiene intermediate, which is trapped by methanol.
New Approach to the Synthesis of Deoxyribonucleoside Phosphoramidite Derivatives
Authors: Hamamoto Shoji , Takaku Hiroshi
Published: July 2006

The deoxyribonucleoside phosphoramidites with various protecting groups at phosphorus have been prepared rapidly in good yields in one-pot reaction from bis(diisopropylamino)chlorophosphine as a new phosphitylating agent without isolation of bis(diisopropylamino)alkoxyphosphines.
Hydrogen Adsorption on N-Modified Ni(755) Surface. Evidence of a Molecular “Precursor” State
Authors: Nozoye Hisakazu
Published: July 2006

Hydrogen adsorption experiments were performed on N-modified Ni(755) surfaces. Sticking probabilities for hydrogen on the surfaces were determined by the analysis of temperature programmed desorption spectra. It is found that the adsorption of hydrogen proceeds through a molecular “precursor” state.
In Situ X-Ray Diffraction Study of Palladium Hydride Electrode during Cathodic Hydrogen Charging or Anodic HCHO Oxidation
Authors: Machida Ken-ichi , Enyo Michio
Published: July 2006

The hydride formation in Pd foils during cathodic hydrogen charging and its reverse process was studied by an in situ X-ray diffraction technique. The α-β phase transformation in the Pd-H system was shown to be accompanied with the formation of PdHx domain in the electrode. The technique was then applied to demonstrate the occurrence of partial hydride formation during the anodic HCHO oxidation on Pd in alkaline media.
New Inorganic Oxide-attached Nb Catalysts Active for Propene Metathesis
Authors: Nishimura Madoka , Asakura Kiyotaka , Iwasawa Yasuhiro
Published: July 2006

SiO2−, Al2O3−, and TiO2-attached Nb-monomer catalysts were prepared by the reactions between Nb(η3-C3H5)4 and surface OH groups of SiO2, Al2O3, or TiO2, followed by the treatments with H2 in the temperature range 323–673 K. These catalysts showed high activities for propene metathesis at the low temperatures 273–310 K, in contrast to the known fact that traditional supported Nb catalysts show almost no activities.
EPR STUDIES OF THE CHARGING PROCESS OF POLYANILINE ELECTRODES
Authors: Kaya Masanori , Kitani Akira , Sasaki Kazuo
Published: July 2006

EPR measurements have been done with a polyaniline coated platinum electrode at various stages of oxidation. The measurements were carried out in situ conditions in both aqueous and non-aqueous solutions. At the initial stage of anodic oxidation, electron spins accumulate in the polymer film upto 1×1020 spins/gram and then decrease gradually with increasing charge of electrolysis.
Stereoselective Synthesis of D-Erythrose and D-Threose Derivatives from d-Glyceraldehyde Acetonide and Their Reactions with 1-(Trimethylsilyl)vinyl Cuprate Reagent. Synthesis of Allitol Hexaacetate
Authors: Kusakabe Masato , Sato Fumie
Published: July 2006

A new and efficient route to the synthesis of trialkoxy derivatives of D-erythrose (1) and D-threose from readily available d-glyceraldehyde acetonide was developed. The addition reaction of 1 with 1-(trimethylsilyl)vinyl cuprate reagent proceeded highly stereoselectively to afford anti addition product, which was then readily converted into allitol hexaacetate.
Regioselective Ring-Cleavage Reaction of Tetrahydrofurans and Tetrahydropyrans Accompanied by Carbon–Carbon Bond Formation
Authors: Oku Akira , Homoto Yukio , Harada Toshiro
Published: July 2006

Various 2-substituted tetrahydrofurans and tetrahydropyrans were cleaved regioselectively accompanied by a simultaneous carbon–carbon bond formation at the highly substituted α carbon atom by using the reagent system of titanium tetrachloride and ally- (or alkynyl-)silanes.
Reduction of the Dodecamolybdophosphate Anion with Triphenylphosphine in a Homogeneous System
Authors: Kawafune Isao
Published: July 2006

The reaction of [n-Bu4N]3PMo12O40 with PPh3 in MeCN was investigated on the basis of FT-IR and electronic absorption spectra. It was found that two-electron reduction occurred on [PMo12O40]3−, accompanied by the transfer of one bridging oxygen in Mo–O–Mo bonds to PPh3.
EFFECT OF ADDITIVES ON THE SURFACE AREA OF OXIDE SUPPORTS FOR CATALYTIC COMBUSTION
Authors: Machida Masato , Eguchi Koichi , Arai Hiromichi
Published: July 2006

Effect of additives on the surface area of oxide supports was investigated to use them for combustion catalysts above 1000 °C. An addition of BaO to Al2O3 was found to suppress the decrease of its surface area at elevated temperatures. The maximum surface area, 6.0 m2/g, was obtained for (BaO)0.14(Al2O3)0.86 after calcination at 1450 °C. The effect of BaO on the surface area of alumina is attributed to the formation of BaO·6Al2O3.