bluuebunny/crossref_metadata_2025 huggingface dataset:
Cathodic Electrodeposition of TiO2 Thin Films for Dye-Sensitized Photoelectrochemical Applications
Authors: Karuppuchamy Subbian , Amalnerkar Dinesh P , Yamaguchi Koichi , Yoshida Tsukasa , Sugiura Takashi , Minoura Hideki
Published: September 2002

A convenient – and quick to realize – approach for cathodic electrodeposition of TiO2 films is suggested. Scanning electron microscopic examination of the resultant films reveals the formation of mesoporous TiO2. Since dye-sensitized photoelectrochemical investigations on cathodically electrodeposited TiO2 films are hitherto unreported, we performed such investigations by sensitizing our mesoporous TiO2 films with cis-bis(4,4′-dicarboxy-2,2′-bipyridine)bis(thiocyanato)ruthenium(II). The preliminary studies exhibit incident photon-to-current conversion efficiency (IPCE) above 35% in the first attempt.
Unusual Fluorescent Properties of 3,4,6-Triphenyl-α-pyrones
Authors: Hirano Keisuke , Minakata Satoshi , Komatsu Mitsuo
Published: September 2002

Novel fluorophores, 3,4,6-triphenyl-α-pyrone derivatives, were synthesized and their spectroscopic properties have been investigated. In the solid state they show intense greenish-yellow fluorescence, but not in solution. It is concluded that the 6-phenyl group is fixed at an angle of about 26° to the pyrone plane in the solid state by molecular packing and this fixation is required for this unique fluorescent property.
Orthorhombic LiMnO2 as a High Capacity Cathode for Lithium-Ion Battery Synthesized by Hydrothermal Route at 170 °C
Authors: Myung Seung-Taek , Komaba Shinichi , Kumagai Naoaki
Published: September 2002

An orthorhombic LiMnO2 having a high capacity was hydrothermally synthesized at 170 °C from Mn3O4 obtained through autoxidation route. The LiMnO2/Li cell demonstrated the initial reversible capacities of about 210 mAh (g-oxide)−1 at 30 °C. After several initial cycling, the cell showed stabilized cycling behavior (175 mAh g−1 at the 30th cycle). We believe that orthorhombic LiMnO2 prepared by a new hydrothermal condition is an excellent candidate for the cathode of coming generation of high capacity material to be applied for lithium-ion secondary battery.
Generation and Behavior of 9-Anthroyloxyl Radicals in Photocleavage of N-(9-Anthroyloxy)-9-fluorenylideneamine
Authors: Saitoh Yasuo , Kaneko Makoto , Segawa Katsunori , Itoh Hiroki , Sakuragi Hirochika
Published: September 2002

9-Anthroyloxyl radicals are generated from photocleavage of the N-O bond of N-(9-anthroyloxy)-9-fluorenylideneamine and 1-(9-anthroyloxy)-2-pyridone in acetonitrile. They are much less reactive in decarboxylation, addition to olefins, and hydrogen-atom abstraction than benzoyloxyl and 1-naphthoyloxyl radicals, and supposedly undergo intramolecular addition to the ipso position to give α-lactonic spiroanthracenyl radicals.
Di-tert-butylphosphate Complexes of Mn(II) and Cu(II) as Single-Source Precursors for Metal Phosphate Materials
Authors: Murugavel Ramaswamy , Sathiyendiran Malaichamy
Published: September 2002

Octahedral Mn(II) and Cu(II) di-tert-butylphosphate (L) complexes [ML2(imz)4] have been synthesized and characterized using IR, UV-vis, luminescence, and EPR spectroscopy and single crystal X-ray diffraction studies. Thermal decomposition of both the complexes (probed by TGA, DTA, and DSC) indicate stepwise elimination of iso-butene, imidazole and water to finally yield the respective ceramic materials Mn(PO3)2 or Cu(PO3)2.
Dichalcogenane Derivatives of Methylenedithio(ethylenedithio)tetrathiafulvalene (MET) and a Derived Metallic Cation-Radical Salt with Screwed Donor Stacks
Authors: Yamada Jun-ichi , Mangetsu Takashi , Akutsu Hiroki , Nakatsuji Shin’ichi , Nishikawa Hiroyuki , Ikemoto Isao , Kikuchi Koichi
Published: September 2002

The synthesis of the dichalcogenane derivatives of MET, (1,3-dioxan-2-yl)methylenedithio(ethylenedithio)tetrathiafulvalene (DOA-MET) and (1,3-dithian-2-yl)methylenedithio(ethylenedithio)tetrathiafulvalene (DTA-MET), and the preparation of their charge-transfer (CT) materials are investigated to explore new organic metals. The resulting (DOA-MET)3AuI2 salt exhibits weak metallic conducting behavior, and has screwed donor stacks.
Partial Oxidation of Methane over Ni Catalysts Supported on Ce-ZrO2 Mixed Oxide
Authors: Roh Hyun-Seog , Dong Wen-Sheng , Jun Ki-Won , Park Sang-Eon
Published: September 2002

A novel catalyst, Ni/Ce-ZrO2 exhibits very high catalytic activity and stability in partial oxidation of methane to synthesis gas. It gives 99.6% CH4 conversion at 850 °C and the activity was maintained for 100 h.
Composition Control of Mixed 2-Aminoethanethiol/Octadecanethiol Monolayers by Underpotentially Deposited Lead on Gold
Authors: Kawaguchi Toshikazu , Shimazu Katsuaki
Published: September 2002

The mixed aminoethanethiol/octadecanethiol monolayers, the surface composition of which was predetermined by the initial coverage of Pb underpotentially deposited on a bare gold electrode during the first step of the preparation, were constructed.
Synthesis and Properties of Perfluoroalkylalkoxy Substituted Benzoic Acid Derivatives
Authors: Nishikawa Etsushi , Yamamoto Jun , Yokoyama Hiroshi
Published: September 2002

Several benzoic acid derivatives having long perfluoroalkyl substituents are synthesized, which form dimers through hydrogen bonding or complexes with bases. These materials are expected to organize nano-phase separated liquid crystalline structure, for instance, a cubic phase, due to the incompatibility between perfluoroalkyl groups and hydrocarbon moieties.
Electrochemical Influence of Tridentate Polypyrazolylborate Ligands: Syntheses and Electrochemistry of Bis(η3-polypyrazolylborato)ruthenium(II) Complexes
Authors: Onishi Masayoshi , Kumagae Siho , Asai Keiko , Kawano Hiroyuki , Shigemitsu Yasuhiro
Published: September 2002

Concerning electrochemically reversible [Ru(III)]/[Ru(II)] redox couples of the substituted bis(η3-polypyrazolylborato)ruthenium(II) complexes [Ru(L1)(L2)], two polypyrazolylborate ligands, L1 and L2, were independently exerted on the oxidation half-wave potentials (E1/2) of the couples. Relative contributions δE(L) of the respective polypyrazolylborates to the E1/2 values were evaluated.
Diphenylamino-Substituted 2,5-Diarylsiloles for Single-Layer Organic Electroluminescent Devices
Authors: Yamaguchi Shigehiro , Endo Tomonori , Uchida Manabu , Izumizawa Takenori , Furukawa Kenji , Tamao Kohei
Published: September 2002

A series of diphenylamino-substituted 2,5-diarylsiloles has been prepared and their photophysical and electrochemical properties have been determined. The single layer EL devices with the ITO/silole/Mg:Ag configuration emitted a greenish-yellow light with a high luminous efficiency.
Dehydration Reactions in Water. Surfactant-type Brønsted Acid-catalyzed Dehydrative Etherification, Thioetherification, and Dithioacetalization in Water
Authors: Kobayashi Shu , Iimura Shinya , Manabe Kei
Published: September 2002

Dehydration reactions such as etherification, thioetherification, and dithioacetalization are efficiently catalyzed by a surfactant-type Brønsted acid in water.
Synthesis, Crystal Structures and Mesomorphic Properties of Liquid Crystals with a N,N′-Bis(tropon-2-yl)piperazine Skeleton
Authors: Yamamoto Emi , Kubo Kanji , Mori Akira , Ujiie Seiji
Published: September 2002

New troponoid liquid crystals with a N,N′-bis(tropon-2-yl)piperazine core were prepared. N,N′-Bis(tropon-2-yl)piperazine derivatives (1) had a smectic C phase with lower thermal stabilities than the corresponding benzenoid derivatives (2), which had a smectic B phase. A single crystal of 1d had distinct layer structures observed in a smectic C phase.
Lewis Acid-Mediated Carboxylation of Fused Aromatic Compounds with Carbon Dioxide
Authors: Suzuki Yutaka , Hattori Tetsutaro , Okuzawa Tomohiro , Miyano Sotaro
Published: September 2002

Direct and regioselective carboxylation of fused aromatic compounds with carbon dioxide is achieved with the aid of a Lewis acid. Thus, treatment of naphthalene, anthracene, and phenanthrene with carbon dioxide (3.0 MPa) in benzene at 40 °C in the presence of AlBr3 gave 1-naphthoic acid, 9-anthracenecarboxylic acid, and 9-phenanthrenecarboxylic acid as the sole acid product in 43, 20, and 34% yields, respectively.
Imprinting and Selective Binding of Di- and Tri-Peptides in Ultrathin TiO2-Gel Films in Aqueous Solutions
Authors: Ichinose Izumi , Kikuchi Takashi , Lee Seung-Woo , Kunitake Toyoki
Published: September 2002

Di- and tri-peptides dissolved in water were alternately assembled with titanium n-butoxide to produce ultrathin nanocomposite films. Upon removal of the peptide templates, the titanium oxide film showed selective binding of peptides from dilute aqueous solution.
The Insertion of Dimethyl Acetylenedicarboxylate into an S-Pd Bond
Authors: Sugoh Kunihiko , Kuniyasu Hitoshi , Kurosawa Hideo
Published: September 2002

The first definitive evidence of insertion of an alkyne into an S-Pd bond has been presented. The reaction of Pd(SAr)2(DPPE) with dimethyl acetylenedicarboxylate (DMAD) gave the cis-insertion product (Z)-Pd-[C(CO2Me)=C(SAr)(CO2Me)](SAr)(DPPE), whose structure was unambiguously determined by X-ray crystallographic analysis.
Preparation and Characterization of Tris(trimethylsilyl)germylzinc Chloride and Bis[tris(trimethylsilyl)germyl]zinc
Authors: Nanjo Masato , Oda Takashi , Mochida Kunio
Published: September 2002

The molecular structure of (Me3Si)3GeZnCl (1) has been determined by single-crystal X-ray diffraction. The germylzinc chloride 1 has a dimeric structure consisting of two μ-Cl atoms. The compound 1 reacted with (Me3Si)3GeLi in diethyl ether to give [(Me3Si)3Ge]2Zn (2), quantitatively. The structure of bis(germyl)zinc 2 has been also elucidated by X-ray diffraction.
Microporous Structure of Alumina Prepared by a Salt Catalytic Sol-Gel Process
Authors: Tanaka Kazuhiko , Imai Tomohito , Murakami Yasushi , Matsumoto Taki , Sugimoto Wataru , Takasu Yoshio
Published: September 2002

A microporous structure of alumina with a narrow distribution of the pore size (∼0.4 nm in diameter) was synthesized by a salt catalytic sol-gel process of dilute Al(OCH(CH3)2)3 and H2O solution without any template molecule. The specific surface area of alumina after the calcination at 300 °C was 960 m2g-1 while it was 170 m2g-1 even after the calcination at 900 °C.
A Novel B-C-N Compound Derived from Melamine Diborate
Authors: Aoki Kaoru , Tanaka Susumu , Tomitani Yukiko , Yuda Masahiro , Shimada Mio , Oda Kohei
Published: September 2002

A new B-C-N compound has been synthesized by thermal decomposition of melamine diborate mixed metal Mg powder in Ar at 1273 K. XRD revealed that the product had turbostratic structure and approximate composition of that was B1.1C1.1N1.0. Properties of the B-C-N compound obtained are discussed.
An Extremely High Insulin-Mimetic Activity of Bis(1,4-dihydro-2-methyl-1-phenyl- 4-thioxo-3-pyridinolato)zinc(II) Complex
Authors: Katoh Akira , Tsukahara Takeshi , Saito Ryota , Ghosh Kallol K , Yoshikawa Yutaka , Kojima Yoshitane , Tamura Asuka , Sakurai Hiromu
Published: September 2002

Vanadyl and zinc(II) complexes with VO(O2S2) and Zn(O2S2) coordination mode, respectively, were synthesized. Among them, bis(1,4-dihydro-2-methyl-1-phenyl-4-thioxo-3-pyridinolato)zinc(II) complex exhibited an extremely high insulin-mimetic activity (IC50=0.04 mM when IC50 value of a positive control, VOSO4 was estimated to be 1.0 mM) compared to vanadyl and zinc(II) complexes reported previously.
Steric Effect is an Additional Possible Cause of Blue-shifting Hydrogen Bonds
Authors: Fang Ying , Fan Jian-Miao , Liu Lei , Li Xiao-Song , Guo Qing-Xiang
Published: September 2002

A novel simple example was found that at least sometimes the steric effect could cause a blue-shifting hydrogen bond, which indicates that Hobza’s recent theory about the origin of the blue-shifting hydrogen bond is not complete.
A Novel High-Pressure NMR Cell Consisting of Double Tube Structure for the Convenient On-Line Measurements
Authors: Umecky Tatsuya , Kanakubo Mitsuhiro , Ikushima Yutaka , Saito Norio , Yoshimura Junko , Yamazaki Hiromi , Yana Junzo
Published: September 2002

We have newly developed a high-pressure polymer NMR cell, which has a versatile use for both batchwise and on-line operations. The high-pressure cell withstands temperatures and pressures, at least, up to 373 K and 35 MPa, respectively. It was demonstrated that the sample solutions of not only viscous carbon tetrachloride but also non-viscous subcritical carbon dioxide smoothly flow in and out at moderate flow rates by measuring the flow rate dependence of the longitudinal relaxation times.
Mercuric Triflate-TMU Catalyzed Hydration of Terminal Alkyne to give Methyl Ketone under Mild Conditions
Authors: Nishizawa Mugio , Skwarczynski Mariusz , Imagawa Hiroshi , Sugihara Takumichi
Published: September 2002

Herein developed mercuric triflate-TMU catalyzed hydration of terminal alkyne is a mild procedure to give methyl ketone in excellent yield with high chemoselectivity. By using 0.05 eq of Hg(OTf)2·(TMU)2 and 3 eq of water, hydration takes place at a reasonable rate in acetonitrile.
A Novel Oxidative Transformation of α-Aminonitriles to Amides
Authors: Yokoshima Satoshi , Kubo Tetsuji , Tokuyama Hidetoshi , Fukuyama Tohru
Published: September 2002

A novel oxidative transformation of α-aminonitriles to amides is reported. Oxidation of α-aminonitriles with peracid, followed by basic treatment affords, amides in good yields. A mechanistic aspect of this transformation is also discussed.
Tandem Cyclizations of Benzopyranylidenetungsten(0) Complexes with Electron-Rich Dienes for the Stereoselective Synthesis of Polycyclic Carbon Skeletons
Authors: Kusama Hiroyuki , Shiozawa Fumiyasu , Shido Masahide , Iwasawa Nobuharu
Published: September 2002

o-Quinodimethanes, generated by the Diels-Alder reactions of benzopyranylidenetungsten(0) complexes with electron-rich dienes, further undergo intramolecular cyclizations to afford novel polycyclic compounds.
Phosphine/Lewis Acid Mediated Reformatsky-type Reaction of α-Bromoketone or -Thioester Derivatives
Authors: Hashimoto Yukihiko , Kikuchi Satoshi
Published: September 2002

The combination of (o-tolyl)3P/TiCl4 effectively promoted the Reformatsky-type reaction of α–bromoketone or -thioester derivatives with various aldehydes, and the corresponding β–hydroxy carbonyl compounds were obtained in good yield with high diastereoselectivity.
A Facile Synthetic Method for Indolic Enamides
Authors: Kuramochi Kouji , Osada Yuko , Kitahara Takeshi
Published: September 2002

We report a facile method for preparing enamides, based on the Curtius rearrangement and acylation of alkenylcarbamate. Using this approach, a total synthesis of coscinamide B, a bis indolic enamide, was achieved.
An Efficient Synthesis of the Piperazinone Fragment of Pseudotheonamide A1 via a Stereoselective Intramolecular Michael Ring Closure
Authors: Shioiri Takayuki , Irako Naoko
Published: September 2002

The stereoselective intramolecular Michael ring closure of the dipeptide efficiently gives the piperazinone fragment of pseudotheonamide A1, a serine protease inhibitor from the marine sponge Theonella swinhoei.
Kinetics of Hydroxyl Radical Reaction with CF2ClOCHO: A Theoretical Investigation
Authors: K. Chandra Asit , Uchimaru Tadafumi , Sugie Masaaki , Sekiya Akira
Published: September 2002

The rate constant for the hydrogen abstraction reaction between CF2ClOCHO and OH radical has been calculated for the first time by using the modified ab initio G2(MP2) and standard transition state theories. The Arrhenius equation for the rate constant, ktotal, within the temperature range of 250 K to 450 K is estimated to be 7.1×10-13exp(-845/T) cm3 molecule-1 s-1.
A Novel Reaction Promoted by Hydrogen Polyiodides (HI2n+1): Cyclization of 1-(1H-3-Indolyl)-4-(methylthio)-2-(p-tolylsulfonyl)-1,3-butadienes Accompanied with 1,2-Sulfonyl Migration
Authors: Matsumoto Shoji , Kishimoto Takuya , Ogura Katsuyuki
Published: September 2002

Reaction of 1-(1H-3-indolyl)-4-(methylthio)-2-(p-tolylsulfonyl)-1,3-butadienes (1) with iodine was accompanied with an unusual 1,2-migration of the sulfonyl group to give an abnormal cyclization product (3). This 1,2-migration reaction was brought about by the action of hydrogen polyiodides that are produced from excess I2 and EtSH. It is noteworthy that the reaction of 1 with HI resulted in formation of a normal product (2).
Novel π-Conjugated Cyclophanes: Magazine Rack Molecules
Authors: Orita Akihiro , Jiang Lasheng , Tsuruta Madoka , Otera Junzo
Published: September 2002

Synthesis of cyclophanes having alternating arylene-ethynylene as well as-ethenylene arrays is described. It is disclosed that these compounds are chiral on the basis of X-ray analysis and fluxional in solution on the basis of NMR spectra.
Alkenyldimethyl(2-thienyl)silanes, Excellent Coupling Partner for the Palladium-Catalyzed Cross-Coupling Reaction
Authors: Hosoi Kazushi , Nozaki Kyoko , Hiyama Tamejiro
Published: September 2002

Introduction of a 2-thienyl group to the silicon atom of alkenylsilanes promoted the cross-coupling reaction with aryl halides mediated by tetrabutylammonium fluoride and a palladium catalyst. The reaction proceeded under extremely mild conditions to afford arylalkenes in high yields.
The First Total Synthesis of (±)-Napyradiomycin A1
Authors: Tatsuta Kuniaki , Tanaka Yoshiki , Kojima Masazumi , Ikegami Hiroshi
Published: September 2002

(±)-Napyradiomycin A1 has been stereoselectively synthesized through a tandem Michael-Dieckmann type reaction and the introduction of a side chain and two chlorine atoms onto the pyranonaphthoquinone core.
Palladium-Catalyzed Asymmetric Alkylation of 2,3-Alkadienyl Phosphates. Synthesis of Optically Active 2-(2,3-Alkadienyl)malonates
Authors: Imada Yasushi , Ueno Katsuya , Kutsuwa Koji , Murahashi Shun-Ichi
Published: September 2002

Asymmetric alkylation of 2,3-alkadienyl phosphates with soft carbon nucleophiles proceeds efficiently in the presence of palladium complex catalyst bearing MeOBIPHEP or BINAP ligand to give optically active functionalized allenes up to 90% ee.
Homoaldol and Aldol Reactions from Common Enolates and Oxiranes: Reaction of Reductively Generated Chromium Enolates through Cationic Rearrangement
Authors: Hojo Makoto , Sakata Kyosuke , Maimaiti Xiamuxikamaer , Ueno Junya , Nishikori Hisashi , Hosomi Akira
Published: September 2002

Enolates generated from α-bromo esters by the reduction with “Bu6CrLi3” react with oxiranes to afford γ-hydroxy esters and β-hydroxy esters, depending on the Lewis acid used as a promoter.
Synthesis of 3,4-Dihydro-2H-pyrroles from γ,δ-Unsaturated Ketone O-Acetyloximes
Authors: Yoshida Masayuki , Kitamura Mitsuru , Narasaka Koichi
Published: September 2002

3,4-Dihydro-2H-pyrroles were synthesized from γ,δ-unsaturated ketone O-acetyloximes by treatment with acetic acid and 1,4-cyclohexadiene in the presence of a catalytic amount of 1,5-naphthalenediol. During the cyclization, syn-anti isomerization of the O-acetyloximes easily occured and so, both stereoisomers of oximes could be employed.
Carbozincation of Dipolar Trimethylenemethane. A New Route to Functionalized Organozinc Reagents
Authors: Nakamura Masaharu , Yoshikai Naohiko , Nakamura Eiichi
Published: September 2002

Dipolar trimethylenemethane species, thermally generated from 2,2-dialkoxy-1-methylenecyclopropane, reacts with a dialkylzinc reagent to generate an allylic zinc reagent, which then reacts in situ with a carbonyl compound to give a hydroxy acetal product as the result of coupling of the three reactants.
Stereoselective Synthesis of Cyclic Ethers by SmI2-Induced Reductive Intramolecular Cyclization
Authors: Matsuo Goh , Kadohama Hitomi , Nakata Tadashi
Published: September 2002

The highly stereoselective syntheses of 2,3-trans-3-hydroxy-tetrahydropyran and oxepane were achieved by the SmI2-induced reductive intramolecular cyclizations from acyclic compounds having an aldehyde and a β-alkoxyacrylate. The syntheses of tetrahydrofuran, oxocane, and oxocene were also accomplished.
A Facile Method for Synthesis of 1,2-Oxazoline Derivative of N-Acetylglucosamine Promoted by Potassium Fluoride
Authors: Shoda Shin-ichiro , Izumi Ryuko , Suenaga Masako , Saito Kenji , Fujita Masaya
Published: September 2002

A potassium fluoride-promoted intramolecular cyclization reaction of 2-acetamido-2-deoxy-α-D-glucopyranosyl chloride took place smoothly, giving the corresponding 1,2-oxazoline derivative in good yield. Potassium fluoride behaves as a nucleophile for anomerization of the glycosyl chloride as well as an acid captor to scavenge the protonic acid liberated. This is an extremely practical method for preparation of sugar oxazoline derivatives with simple experimental procedures.
A New Method for the Synthesis of Stannyl Ethers by Acid-Catalyzed Reaction of Alcohols with Allyltributylstannane
Authors: Yamago Shigeru , Yamada Takeshi , Nishimura Ryuji , Ito Hiroki , Mino Yosuke , Yoshida Jun-ichi
Published: September 2002

Stannyl ethers are prepared by triflic acid-catalyzed reaction of alcohols with tributylstannane or allyltributylstannane at room temperature. The stannyl ethers thus prepared can be successfully used for the β-bromogycoside-mediated glycosylation reactions.
Efficient Lipase-catalyzed Enantioselective Acylation under Reduced Pressure Conditions in an Ionic Liquid Solvent System
Authors: Itoh Toshiyuki , Akasaki Eri , Nishimura Yoshihito
Published: September 2002

Lipase-catalyzed transesterification was demonstrated using methyl esters as acyl donors under reduced pressure in an ionic liquid ([bmim]PF6) solvent system. The transesterification of 5-phenyl-1-penten-3-ol took place smoothly under reduced pressure at 27 hPa at 40 °C when methyl phenylthioacetate was used as acyl donor in [bmim]PF6, and we succeeded in obtaining the corresponding acylated compound in optically pure form; this makes it possible to use lipase repeatedly because there was no drop in the reaction rate despite three repetitions of the process.
Anionic Ring-Opening Polymerization of Cyclic Thiocarbonates Containing Norbornene and Norbornane Groups Undergoing Volume Expansion on Polymerization
Authors: Kakimoto Keiichiro , Nemoto Nobukatsu , Sanda Fumio , Endo Takeshi
Published: September 2002

Six-membered cyclic thiocarbonate derivatives, 5,5-(bicyclo[2.2.1]hept-2-en-5,5-ylidene)-1,3-dioxane-2-thione (1) and 5,5-(bicyclo[2.2.1]heptan-5,5-ylidene)-1,3-dioxane-2-thione (2) underwent anionic ring-opening polymerization initiated by 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) to afford polythiocarbonates accompanying 12.3 and 12.6% volume expansion, respectively.
Nucleophilic Allylation-Heterocyclization via Bis-π-allylpalladium Complexes: Synthesis of Five- and Six-Membered Heterocycles
Authors: Bao Ming , Nakamura Hiroyuki , Inoue Akihiko , Yamamoto Yoshinori
Published: September 2002

The reaction of the allylic halides 5–9 having an aldehyde or an imine moiety in the molecule with allyltributylstannane proceeded smoothly in the presence of Pd2•dba3•CHCl3 (5 mol%) in DMF or THF, giving the corresponding heterocycles 10–14 in good to high yields. The Stille coupling product was not obtained under these reaction conditions.
A New Silyl Ether-Type Linker Useful for the Automated Synthesis of Oligonucleotides Having Base-Labile Protective Groups
Authors: Kobori Akio , Miyata Kenichi , Ushioda Masatoshi , Seio Kohji , Sekine Mitsuo
Published: September 2002

A new silyl-type linker for the automated solid-phase synthesis of oligodeoxynucleotides was developed. A hydrosilane-type reagent for introduction of the silyl linker was synthesized in an overall yield of 50% from 1,4-dibromobenzene. By using this linker, an oligonucleotide having base-labile protecting groups could be isolated from the controlled pore glass under neutral conditions.
An Intriguing Effect of Polymer-Bound Lithium Amides in Catalytic Enantioselective Rearrangement of meso-Epoxides Mediated by Chiral Lithium Amides
Authors: Asami Masatoshi , Seki Atsushi
Published: September 2002

Polymer-bound lithium dialkylamides were prepared from the corresponding polymer-bound amines and butyllithium. The reagent was successfully employed as an in situ regenerating agent of a chiral lithium amide in a catalytic enantioselective rearrangement of meso-epoxides, and chiral allylic alcohols were obtained in up to 95% ee.
Highly Terminal-Selective Epoxidation of Linolenic Acid with an Amphiphilic Iron Porphyrin Catalyst Casted in Bilayer Membranes
Authors: Naruta Yoshinori , Goto Masa-oki , Tawara Toshifumi , Tani Fumito
Published: September 2002

An amphiphilic iron porphyrin having four hexadecanoic acid chains on each face of the porphyrin was prepared and the catalytic epoxidation of linolenic acid with the heme-casted bilayer membranes was achieved in high regioselectivity at the terminal double bond of the substrate. The orientation of the porphyrin ring in the membrane was determined to be parallel to the aqueous-bilayer interface by means of ESR.
Enantioselective Alkylation of Aldehydes with Diethylzinc Using a New Catalyst System, ((R)-Thiolan-2-yl)diphenylmethanol and Metal Alkoxides
Authors: Shiina Isamu , Konishi Katsuhiko , Kuramoto Yu-suke
Published: September 2002

Various optically active secondary alcohols are obtained by asymmetric alkylation of aldehydes with diethylzinc by way of a new catalyst system, ((R)-thiolan-2-yl)diphenylmethanol and several metal alkoxides. The transition states are also discussed in terms of experimental results and theoretical calculation.
Nanoporous Solid Acid Catalyst for the Diels-Alder Reaction of 1,3-Dienes with Acrylates
Authors: Onaka Makoto , Hashimoto Naoki , Yamasaki Ryota , Kitabata Yasuyoshi
Published: September 2002

Nanoporous aluminosilicate, Al-HMS with a high aluminum content, strong acidity, and nanoporosity was found to catalyze the Diels-Alder reaction of 1,3-dienes with methacrylate and acrylate, and turned out to be a green alternative to homogeneous acid catalysts.
Asymmetric Autocatalysis of Pyrimidyl Alkanol Induced by Optically Active 1,1′-Binaphthyl, an Atropisomeric Hydrocarbon, Generated from Spontaneous Resolution on Crystallization
Authors: Sato Itaru , Osanai Shunji , Kadowaki Kousuke , Sugiyama Tadashi , Shibata Takanori , Soai Kenso
Published: September 2002

An atropisomeric hydrocarbon, (R)-1,1′-binaphthyl, acts as a chiral initiator of asymmetric autocatalysis of pyrimidyl alkanol in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde to afford (S)-5-pyrimidyl alkanol 2 with 96% ee. On the other hand, in the presence of (S)-1,1′-binaphthyl, the reaction affords (R)-2 with 94% ee.
Highly Z-Selective Synthesis of Disubstituted α,β-Unsaturated Cyanides and Amides Using 10-P-5 Wittig Type Reagents
Authors: Kojima Satoshi , Kawaguchi Kazuhiro , Matsukawa Shiro , Uchida Keiichiro , Akiba Kin-ya
Published: September 2002

Phosphoranes (10-P-5) bearing cyanomethyl, acetamide, and N,N-dimethylacetamide groups were examined for Wittig type reactions. All three reacted to give the corresponding olefins. The reaction of the cyanomethyl reagent with aldehydes gave α,β-unsaturated cyanides with high Z-selectivity in the case of aliphatic aldehydes (Z:E=94:6 to 99:1). On the other hand, the reactions of the two amide reagents with aldehydes yielded α,β-unsaturated amides with high Z-selectivity for both aromatic and aliphatic aldehydes (Z:E=99:1 to >99:<1).
Tertiary Amine-Accelerated Allylgallation of Terminal Alkynes
Authors: Takai Kazuhiko , Ikawa Yoshito , Ishii Keijiro , Kumanda Makoto
Published: September 2002

Allylic gallium sesquibromides prepared by reduction of allylic bromides with gallium metal in the presence of a catalytic amount of indium, add to terminal alkynes with the aid of a tertiary amine to give 1,4-dienes.
Preparation of Porphyrin-stoppered Rotaxane Aiming at Immobilization on Substrate
Authors: Asakawa Masumi , Ikeda Taichi , Yui Nobuhiko , Shimizu Toshimi
Published: September 2002

The porphyrin-stoppered rotaxane was prepared from dibenzo-24-crown-8 (DB24C8) and the secondary ammonium ion derivative end-capped by the axial coordination of rhodium(III) tetra-(3,5-di-tert-butylphenyl) porphyrin [TBPP Rh(III) Cl]. This rotaxane molecule was designed aiming at the immobilization on a substrate and the analysis of the physicochemical properties as a single molecule.
Synthesis, Characterization of a Novel Compound SnEr2O4
Authors: Zhang Yong , Zhang Ke Li , Jia Man Ke , Tang Hao , Sun Ju Tang , Yuan Liang Jie
Published: September 2002

A novel compound, a rare earth complex oxide SnEr2O4 was synthesized by the thermal decomposition of its oxalate precursor prepared by Rheological Phase Reaction Method. TG, IR, XRD and XPS were used to prove the formation of the compound SnEr2O4. The structure of SnEr2O4 was defined by Rietveld analysis. SnEr2O4 is cubic, Pm3m, a=7.3735 Å, V=400.88 Å3, Z=4, Dx=8.573 g/cm3, Dm=8.2 g/cm3.
Acceleration of Hydrolysis of Acetylsalicylic Acid in AOT/Supercritical Ethane Reverse Micelles
Authors: Shervani Zameer , Ikushima Yutaka
Published: September 2002

In situ UV-vis spectroscopy has been applied to study the hydrolysis of acetylsalicylic acid, as a model reaction, in sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/supercritical ethane reverse micelles in the presence of imidazole as a catalyst. A 55-fold increase in the rate constant was observed in AOT/supercritical ethane micelles compared to the reaction carried out in aqueous buffer medium. The promotion of hydrolysis in the micelles as compared to aqueous solution has originated from compartmentalization of water-soluble reactant and the catalyst in the aqueous core of micelles.
Ni(0)-Catalyzed Bismetallative Cyclization of 1,3-Diene and a Tethered Aldehyde in the Presence of Bu3SnSiMe3
Authors: Sato Yoshihiro , Saito Nozomi , Mori Miwako
Published: September 2002

Ni(0)-Catalyzed bismetallative cyclization of 1,3-diene and a tethered aldehyde in the presence of Me3SiSnBu3 gave the corresponding cyclized product, having an allylstannyl group in the side chain, which could be used as an allylstannane in a coupling reaction with benzaldehyde.
Electrochemical Change of the Photonic Stop Band of the Ordered Macroporous WO3 Films
Authors: Sumida Takayuki , Wada Yuji , Kitamura Takayuki , Yanagida Shozo
Published: September 2002

Three-dimensional macroporous tungsten trioxide (WO3) was electrochemically prepared by using the polystyrene opal as a template. The photonic stop band of the porous WO3 film could be changed when the WO3 was intercalated with lithium cation by the electrochemical method. The change of the stop band was attributed to the change of the refractive indices accompanied with the electrochromism of WO3.
A Catalytic Aldol Reaction between Ketene Silyl Acetals and Aldehydes Promoted by Lithium Amide under Non-acidic Conditions
Authors: Fujisawa Hidehiko , Mukaiyama Teruaki
Published: September 2002

A catalytic aldol reaction between trimethylsilyl enol ethers and aldehydes by using lithium diphenylamide, a Lewis base catalyst, in DMF or pyridine solvent proceeded smoothly to afford the corresponding aldols under mild conditions.
Reversible Formation of Nanoparticles by Thermoresponsive Dehydroalanine Polymer: Poly(N-isobutyryldehydroalanine methyl ester)
Authors: Tezuka Yoshihiko , Bando Yoshitaka , Tanaka Hitoshi
Published: September 2002

Two kinds of dehydroalanine monomers, N-isobutyryl dehydroalanine (iBDHA) and its methyl ester (iBDHAM), were synthesized and their homopolymers were prepared by free radical polymerization. While poly(iBDHA) did not show any phase transition in water, poly(iBDHAM) exhibited the lower critical solution temperature (LCST) at 19 °C to form colloidal dispersion of nanoparticles with 60 nm diameter above the LCST. This nanoparticle formation was thermoreversible.
Mesomorphic Properties of Bis(5-alkoxy-2-aminotroponato)coppers and Their N, N-Dimethyl Derivatives
Authors: Mori Akira , Yamamoto Shin-ichi , Takemoto Manabu , Ujiie Seiji
Published: September 2002

Unsymmetrical bis(5-alkoxy-2-aminotroponato)coppers showed tilted smectic C and G/J phases due to the alignment of the outboard dipole moment. Furthermore, their N,N-dimethyl derivatives had nematic and smectic A phases with low transition temperatures due to the reduction of the lateral overlapping and the steric repulsion of the methyl groups.
Synthesis and X-ray Structures of Rhodium Complexes of N21, N22-Bridged Porphyrin
Authors: Setsune Jun-ichiro , Yamauchi Takashi , Tanikawa Sachiko
Published: September 2002

(η4-1,5-Cyclooctadienyl)rhodium(I) complex with a bidentate N21, N22-bridged porphyrin ligand was prepared. The η4-1,5-cyclooctadiene ligand was easily replaced by carbon monoxide to give the corresponding (dicarbonyl)rhodium(I) porphyrin. The structures of these two complexes were proven by X-ray crystallography.
Enhancement of Surface Plasmon Resonance Sensing for DNA Hybridization Using Colloidal Au Attached Probe DNA
Authors: Yamaguchi Akira , Juodkazis Saulius , Matsuo Shigeki , Misawa Hiroaki
Published: September 2002

In this study, we demonstrate that the Au particle modified probe DNA monolayer can enhance the surface plasmon resonance (SPR) signal for measuring hybridization of unlabeled DNA molecules. The Au particles adsorbed on single stranded (ss)- and double stranded (ds)-DNA monolayers have different optical interaction with surface of Au thin film, and this difference induces the enhancement of the SPR signal.
Highly Stereoselective Radical Reduction of α-Bromo-α-fluoro-β-hydroxy Esters with Tributyltin Hydride Leading to threo-α-Fluoro-β-hydroxy Esters
Authors: Mima Kazuhide , Ishihara Takashi , Kuwahata Saki , Konno Tsutomu , Yamanaka Hiroki
Published: September 2002

α-Bromo-α-fluoro-β-hydroxy esters, prepared as isomeric mixtures by the zinc-mediated coupling reaction of dibromo-fluoroacetate with aldehydes at -20 °C, were successively treated with trimethylaluminium at -15 °C for 0.5 h and with tributyltin hydride in the presence of a catalytic amount of triethylborane at -15 °C for 4 h or at -78 °C for 6 h to give preferentially the threo-isomers of the corresponding α-fluoro-β-hydroxy esters in good yields.
Synthesis of Novel Alternating π-Conjugated Copolymers Having [2.2]Paracyclophane and Fluorene Units in the Main Chain Leading to the Blue Light-Emitting Materials
Authors: Morisaki Yasuhiro , Chujo Yoshiki
Published: September 2002

Novel through-space π-conjugated polymers having [2.2]paracyclophane and fluorene units were synthesized by Heck-Sonogashira coupling reaction. The polymers exhibited strong blue fluorescence in solution and in the solid state.
Effect of Electric Field on the Morphology of Silver Nanocrystals Prepared by γ-Irradiation
Authors: Wang Feng , Ni Yonghong , Ge Xuewu , Zhang Zhicheng
Published: September 2002

The flake-like silver nanocrystals were prepared by γ-irradiation in the presence of an electric field. However, only spherical silver nanoparticles were obtained without the electric field.
Self-Assembly of A Novel Sulphonate Silver(I) Complex
Authors: Sun Daofeng , Cao Rong , Liang Yucang , Hong Maochun
Published: September 2002

Self-assembly of dipotassium salt of piperazine-1,4-bis(2-ethanesulfonic acid) (K2pesp) with AgNO3 in H2O/DMF gave rise to a novel three-dimensional sulphonate silver(I) complex, [Ag2(μ2-OH2)(pesp)]n (1). Each silver(I) ion is coordinated by one nitrogen and two oxygen atoms from three pesp ligands and one oxygen atom from coordinated water molecule in a distorted tetrahedral geometry.
Allylation of Carbonyl Compounds with Allylic Gallium Reagents
Authors: Tsuji Takashi , Usugi Shin-ichi , Yorimitsu Hideki , Shinokubo Hiroshi , Matsubara Seijiro , Oshima Koichiro
Published: September 2002

Allylic gallium reagents, prepared from gallium trichloride and the corresponding allylic Grignard reagents, allylated carbonyl compounds in good yields in an aqueous medium as well as in organic solvent.
Direct Synthesis of β-Alkenylpyrroles by Pd(II)-Catalyzed Addition of Pyrroles to Alkynoates
Authors: Oyamada Juzo , Lu Wenjun , Jia Chengguo , Kitamura Tsugio , Fujiwara Yuzo
Published: September 2002

β-Alkenylpyrroles were prepared directly by Pd(II)-catalyzed addition of pyrroles to alkynoates at room temperature. This procedure was applied to direct synthesis of a β-alkenylpyrrole, the pyrrole fragment of haemin.
Duplex Stabilizing Effect and Nuclease Resistant Property of Novel Oligonucleotides Containing C-2 Branched Polyamine-Bearing Deoxyinosine Derivative
Authors: Shinozuka Kazuo , Onodera Masaaki , Ikeda Hiroshi , Sawai Hiroaki
Published: September 2002

Novel oligodeoxyribonucleotides containing a C-2 branched polyamine-bearing deoxyinosine moiety at either inside-region or the 5′-terminus of the sequence exhibited enhanced nuclease resistant property. Among them, only the oligomers having the modified deoxyinosine residue at inside-region brought about duplex stabilizing effect upon mixing with the complements.
Solid-Liquid Separation of Lanthanide/Lanthanide and Lanthanide/Actinide Using Ionic Imprinted Polymer Based on a DTPA Derivative
Authors: Vigneau Olivier , Pinel Catherine , Lemaire Marc
Published: September 2002

Competitive extraction of Gd/La, Gd/Nd, Gd/Eu, Gd/Lu and Am/Eu with a gadolinium-imprinted polymer leads to improvement of the selectivity compare to the corresponding blank material.
Electrochemical Reduction of Nitrate Ions on Tin-Modified Platinum and Palladium Electrodes
Authors: Shimazu Katsuaki , Goto Ryo , Tada Keijiro
Published: September 2002

The tin-modified platinum and palladium-deposited gold (Sn/Pt and Sn/Pd/Au) electrodes have exhibited a higher electrocatalytic activity for the reduction of nitrate than any electrode so far reported in the literature. Ammonium ions were predominantly formed on Sn/Pt, while N2O and/or N2 were the most likely main products on Sn/Pd/Au.
Metal Ions Affect on the Photodynamic Actions of Cyclodextrin-Modified Hypocrellin
Authors: Ou Zhi-Ze , Chen Jing-Rong , Wang Xue-Song , Zhang Bao-Wen , Cao Yi
Published: September 2002

Cu2+, Fe2+ and Fe3+ could chelate with cyclodextrin-modified hypocrellin (HBCD) efficiently and the UV-visible spectra of the resultant metal complexes red shifted by more than 40 nm. ESR study revealed that the hydroxyl radical was the main product during irradiation of these metal complexes because Cu2+, Fe2+ and Fe3+ initiated the Fenton reaction. Also, these metal complexes photodamaged the calf thymus DNA in the liposome system 20 folds faster than that in the buffer solution due to the initiation of lipid peroxidation.
Formation of Organic Monolayer on a Hydrogen Terminated Si(111) Surface via Silicon-Carbon Bond Monitored by ATR FT-IR and SFG Spectroscopy: Effect of Orientational Order on the Reaction Rate
Authors: Quayum M Emran , Kondo Toshihiro , Nihonyanagi Satoshi , Miyamoto Dai , Uosaki Kohei
Published: September 2002

The formation of an octadecyl monolayer on a hydrogen terminated Si(111) surface in neat octadecene at 200 °C was followed by attenuated total reflectance Fourier transform infrared (ATR FT-IR) and sum frequency generation (SFG) spectroscopy and ellipsometry. Until ca. 60% of the monolayer was formed, the monolayer formation proceeded with simple first-order reaction kinetics and the monolayer was disordered. As the coverage steadily increased, the order of the monolayer became very high and the rate of the monolayer formation became significantly slower.
A Useful and Convenient Synthetic Procedure for Hydrolysis of Thioglycosides
Authors: Mondal Ejabul , Barua Pankaj M Bujar , Bose Gopal , Khan Abu T
Published: September 2002

Various thioglycosides 1 are smoothly hydrolyzed chemoselectively to the corresponding 1-hydroxy sugars 2 in good yields at 0–5 °C by employing (NH4)6Mo7O24·4H2O-H2O2 or H2MoO4·H2O-H2O2 to promote oxidation of ammonium bromide in the presence of perchloric acid in CH2Cl2-H2O solvent system. Mild conditions, good yields, no side reactions such as bromination either at the anomeric position or double bond, and even oxidation at the sulfur are some of the major advantages.
Cobalt Catalyst Heterogenized on SBA-15 for p-Xylene Oxidation
Authors: Burri David Raju , Jun Ki-Won , Kim Young-Ho , Kim Ji Man , Park Sang-Eon , Yoo Jin S
Published: September 2002

Cobalt(III) complex has been heterogenized onto a mesoporous material SBA-15 and successfully applied to the liquid phase oxidation of p-xylene in spite of not using either a solvent or bromide ion.
Synthesis and Morphology Control of SBA-1 Mesoporous Silica with Surfactant of Cetyltrimethylammonium Bromide (CTMABr)
Authors: Che Shunai , Sakamoto Yasuhiro , Terasaki Osamu , Tatsumi Takashi
Published: September 2002

The 3d-cubic Pm3-n SBA-1 mesoporous silica synthesized under highly acidic conditions using cetyltrimethylammonium bromide exhibited a distinct octadecahedron crystal shape in contrast to the material synthesized in the presence of cetyltriethylammonium bromide under less acidic conditions, which showed a highly isotropic morphology with fifty-four or more crystal faces.
The Internal Structure and Tribology of Calcium Lauroyl Taurate
Authors: Nonomura Yoshimune , Kurita Kenkou , Kashimoto Akio , Hotta Hajime , Kaneko Yohei , Iitaka Kazuhiro
Published: September 2002

Calcium lauroyl taurate (C11H23CONH(CH2)2SO3·0.5Ca, CaLT) was synthesized, and the internal structure and tribology were studied. The powder of CaLT is a plate type crystal whose structure is lamellar at room temperature. When the powder is applied to an artificial skin, the frictional coefficient is lower than that for other solid lubricants. Such a high lubricity is caused by disintegration of the powder aggregates, cleavage of the lamellar layers, and deformation of the powder particles.
Photoinduced Hydrogen Production from Sucrose with the Combination System of Water-soluble Zinc Porphyrin and Enzymes
Authors: Saiki Yoshinobu , Ishikawa Yuichi , Amao Yutaka
Published: September 2002

Photoinduced hydrogen production from sucrose as an electron-donating reagent has been investigated. When the sample solution containing sucrose, invertase, glucose dehydrogenase, nicotinamide adenine dinucreotide (NAD+), zinc tetraphenylporphyrin tetrasulfonate (ZnTPPS), methylviologen and colloidal platinum was irradiated, continuous hydrogen production was observed.
Intramolecular Dimerization of Silylenes Leading to Novel Cyclic Disilenes
Authors: Sakurai Hideki , Iimura Tomohiro , Matsumoto Shigeki , Sanji Takanobu
Published: September 2002

Photochemically generated 1,6-diphenyl-1,6-disilahexane-1,1,6,6-tetrayl (1,6-bissilylene) undergoes intramolecular dimerization to give 1,2-diphenyl-1,2-disilacyclohex-1-ene.
Reaction-Controlled Phase-Transfer Catalytic Oxidative Cleavage of Cyclopentene to Glutaraldehyde over Peroxy-niobic Acid
Authors: Chen Hao , Dai Wei-Lin , Jiang An-Ren , Deng Jing-Fa
Published: September 2002

The oxidative cleavage of cyclopentene to glutaraldehyde with aqueous H2O2 was performed over a peroxy-niobic acid catalyst with high yield (72%) and complete conversion of cyclopentene under mild reaction conditions. Peroxy-niobic acid has been shown as a “reaction-controlled phase-transfer” catalyst, which has the advantages of both homogeneous and heterogeneous catalysts.
Synthesis and Base-Pairing of Self-Complementary Mesomeric Betaines of Guanine
Authors: Schmidt Andreas , Kobakhidze Nikoloz
Published: September 2002

Substitution of 8-H of guanine-N-oxide was accomplished by pyridine, 4-dimethylaminopyridine and acetyl chloride, respectively, to give a cationic purine base after hydrolysis. Deprotonation formed mesomeric betaines of guanine. ESI mass spectrometry and 1H NMR revealed their self-complementarity. Base-pairing to cytosine was observed with a fully protected DNA model compound.
Highly Selective Formation of Cyclopentanol through Liquid-Phase Cyclopentene Hydration over MCM-22 Catalysts
Authors: Nuntasri Duangamol , Wu Peng , Tatsumi Takashi
Published: September 2002

MCM-22 catalyst exhibits an extremely high shape selectivity not observed on other zeolites of MFI, MOR and BEA structures, in that it effectively catalyzes the liquid-phase hydration of cyclopentene at a conversion up to 10% and a cyclopentanol selectivity as high as 99%.
Preparation of Long TiO2 Nanotubes from Ultrafine Rutile Nanocrystals
Authors: Zhang Qinghong , Gao Lian , Sun Jing , Zheng Shan
Published: September 2002

The morphological dependence of TiO2 nanotubes on the particle size and crystalline phase of raw materials was observed, and long and uniform TiO2 nanotubes with lengths up to 500 nm were prepared from rutile TiO2 nanoparticles (7.2 nm).
Mg-Promoted Regioselective Carbon-Silylation of α-Phosphorylacrylate Derivatives
Authors: Kyoda Makoto , Yokoyama Takamichi , Kuwahara Takeshi , Maekawa Hirofumi , Nishiguchi Ikuzo
Published: September 2002

Treatment of aromatic α-phosphorylacrylate derivatives 1a-h with Mg turnings in the presence of trimethylsilyl chloride brought about facile and regioselective C-silylation to give the corresponding β-silylated phosphonates 2a-h in excellent yields. The reaction took place smoothly for activated olefins possessing appropriate reduction potentials and may be initiated by electron transfer from Mg to 1a-h.
Spontaneous Reduction of Gold(III) to Gold(I) That Leads to the Formation of S-Bridged CoIII2AuI2 Tetranuclear Structure Composed of Unprecedented C
1-cis(S)-[Co(aet)2(en)]+ Units: Synthesis and Characterization of C
2
C
2- and C
1
C
1-[Au2{Co(aet)2(en)}2]4+
Authors: Konno Takumi , Hattori Masashi , Yoshimura Takashi , Hirotsu Masakazu
Published: September 2002

The 1:2 reactions of C2C2-[Ni{Co(aet)2(en)}2]4+ (C2C2-[1]4+; aet=2-aminoethanethiolate, en=ethylenediamine) with AuI or AuIII in water gave an S-bridged CoIII2AuI2 tetranuclear complex, C2C2-[AuI2{Co(aet)2(en)}2]4+ (C2C2-[2]4+). On the other hand, the corresponding 1:1 reaction with AuIII led to the geometrical isomerization of C2-cis(S)- to C1-cis(S)-[Co(aet)2(en)]+ unit to produce C1C1-[2]4+.
Arylaldehydes-pentafluorophenyl Hydrazones as Second-order Nonlinear Optical Chromophores: A Novel Approach for Remarkably Defeating the Nonlinearity-transparency Trade-off
Authors: Hua Jianli , Zhang Wei , Li Zhen , Qin Jingui , Shen Yaochun , Zhang Yu , Lu Zuhong
Published: September 2002

A series of new arylhydrazone chromophores containing pentafluorophenyl as electronic acceptor are synthesized and found to exhibit significantly blue-shifted absorption in comparison with the corresponding 4-nitrophenyl analogues while keeping β value in the same order, and this may provide a new opportunity for defeating nonlinearity-transparency trade-off in designing second-order nonlinear optical chromophores.
A Novel One Step Photocatalytic Synthesis of 2-Methyl Quinoxaline from o-Phenylenediamine and Propyleneglycol over TiO2/zeolite Mediated System
Authors: Subba Rao K V , Subrahmanyam M
Published: September 2002

Molecular oxygen, Light, TiO2/zeolite composite promoted 2-methyl quinoxaline (2-MQ) and quinoxaline (Q) synthesis from o-phenylenediamine and propyleneglycol. The oxidation of propyleneglycol and its further cyclization with o-phenylenediamine formed 2-MQ and subsequent oxidative demethylation of 2-MQ via the corresponding acid, formed quinoxaline (Q).
A Novel One Step Synthesis of trans-1,4,6,9-tetraazabicyclo[4.4.0]decane over TiO2/Zeolite Composite Photocatalysts
Authors: Subba Rao K V , Srinivas B , Prasad A R , Subrahmanyam M
Published: September 2002

A novel one step intermolecular cyclization of ethanol and ethylenediamine towards the formation of trans-1,4,6,9-tetraazabicyclo[4.4.0]decane (TAD) 3 has been achieved for the first time over TiO2/zeolite composite photocatalysts using solar/artificial light at ambient temperature.
Measurement of Carbon Amount in Carbon-coated Graphite by Thermal Analysis
Authors: Wang Hongyu , Fukuda Kenji , Yoshio Masaki , Abe Takeshi , Ogumi Zempachi
Published: September 2002

Carbon-coated natural graphite is a promising candidate for lithium-ion battery anode material. The amount of carbon-coating plays a very significant role in the electrochemical performance of this type of anode material. A simple and believable method based on the thermal analysis of air oxidation for carbon-coated natural graphite has been introduced to measure carbon-coating weight portions in the composite material.