bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Isomerization of Silicon and Germanium Sesquichalcogenides, Thex4M4E6 (M = Si, Ge; E = S, Se)
Authors: Unno Masafumi , Ishii Daisuke , Matusmoto Hideyuki
Published: May 2005

The isomerization of the sesquichalcogenides Thex4M4E6 (Thex = 1,1,2-trimethylpropyl, 1: M = Si, E = S; 2: M = Si, E = Se; 3: M = Ge, E = S; 4: M = Ge, E = Se) with the “double-decker”-type structures (Thex2M2E2)2E2, (1dd—4dd) to the corresponding compounds with the adamantane-type structures Thex4M4E6 (1ad—4ad) was studied. The skeletal rearrangement has been observed to be reversible in the case of sesquichalcogenides 1, 2, and 4; for 1 and 4, the isomerization has reached an equilibrium with preference for adamantane-type structures 1ad and 4ad, respectively, while the equilibrium in 2 has lain more to “double-decker”-type 2dd. On the other hand, the isomerization of 3dd to 3ad has been observed to be irreversible under the condition employed. In the temperature ranges 433—453 K (1dd), 373—393 K (3dd), and 358—383 K (4dd), the equilibrium has followed reversible first-order kinetics. The thermodynamic parameters determined for the forward isomerization, the “double-decker”-type structures (dd) → adamantane-type structures (ad), are as follows: for 1dd → 1ad, Ea = 35.9 ± 0.1 kcal mol−1, ln A = 30.8 ± 0.2 s−1, ΔH‡ = 35.0 ± 0.1kcal mol−1, ΔS‡ = −0.044 cal mol−1 K−1; for 3dd → 3ad, Ea = 35.9 ± 0.1 kcal mol−1, ln A = 38.3 ± 0.2 s−1, ΔH‡ = 34.6 ± 0.1 kcal mol−1, ΔS‡ = 13.7 cal mol−1 K−1; for 4dd → 4ad, Ea = 32.3 ± 0.1 kcal mol−1, ln A = 35.7 ± 0.1 s−1, ΔH‡ = 31.7 ± 0.3 kcal mol−1, ΔS‡ = 10.4 cal mol−1 K−1. The X-ray structure of new sesquichalcogenide 2ad is also reported.
Ruthenium-Catalyzed Cyclopropanation of Norbornene with Propargyl Alcohol
Authors: Matsushima Yuji , Kikuchi Hidetoshi , Uno Mitsunari , Takahashi Shigetoshi
Published: May 2005

Norbornene as well as its 5,6-disubstituted derivatives and oxa-norbornene undergoes a novel cyclopropanation with propargyl alcohol in methanol containig cationic (η5-cyclopentadienyl)tris(acetonitrile)ruthenium complexes as catalysts to give exo-3-acetyltricyclooctane derivatives. Cyclopentadienylruthenium catalysts having an electron-withdrawing substituent on the Cp ligand exhibited the highest activity and the cyclopropanation proceeded even at −20 °C. On the basis of a deuterium labeling experiment, a reaction mechanism involving a ruthenacycle intermediate is proposed.
Total Synthesis of a Macrocyclic Antibiotic, Micrococcin P1
Authors: Okumura Kazuo , Suzuki Taishi , Nakamura Yutaka , Shin Chung-gi
Published: May 2005

The first total synthesis of a macrocyclic antibiotic, micrococcin P1 (1), was achieved. This antibiotic has a unique structure and is constructed of four components called Fragments A, B, C, and D. In particular, the structures of the central pyridine skeleton (Fragment A) and the exocyclic side-chain (Fragment D) of 1 are slightly different from those of a similar antibiotic, micrococcin P (2). By various chemical modifications of the synthetic method for 2, the synthesis of the central 2,3,6-tris(substituted thiazolyl)pyridine segment [Fragment A—C] 15 from ethyl 2-[6-dimethoxymethyl-2-(1-ethoxyvinyl)-3-pyridyl]thiazole-4-carboxylate (9), followed by coupling of 15 with the Fragments B and D moieties, synthesized independently, gave the protected Fragment A-B-C-D segment. Final intramolecular cyclization by using (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate as a condensing agent under high-dilution conditions and then deprotection of all the protecting groups with trifluoroacetic acid were effected successfully to give the expected synthetic 1.
Excimer Fluorescence of N-(1-Pyrenyl)iodoacetamide-Labeled Spectrin
Authors: Yamaguchi Takeo , Furukawa Yoichi , Terada Shigeyuki
Published: May 2005

The structure of spectrin in aqueous solutions or erythrocyte ghosts was characterized by using a fluorophore, N-(1-pyrenyl)iodoacetamide (NPIA). The excimer fluorescence of NPIA was clearly observed in isolated spectrin, but not in other proteins such as actin, bovine serum albumin, and lysozyme. The excimer disappeared upon addition of sodium dodecyl sulfate, but reappeared by dialysis. Further, the excimer appeared in spectrin extracts from ghosts labeled at 37 °C with NPIA. Interestingly, no such excimer in spectrin extracts appeared upon pretreatment of ghosts with diamide, and then N-ethylmaleimide. However, when such double-treated ghosts were exposed to dithiothreitol before NPIA labeling, the excimer fluorescence reappeared. Further, excimer fluorescence was observed in ghosts which were pretreated above 30 °C, especially at 50 °C, and then labeled at 0 °C with NPIA. The data of nondenaturing polyacrylamide gel electrophoresis and CD spectra showed marked changes in the structure of spectrin at 50 °C. We thus suggest that the excimer fluorescence of NPIA is useful to monitor the structural changes of spectrin.
1 : 2 Polycondensation of 3,3′,4,4′-Biphenyltetramine and 1,1′-Ferrocenedimethanol Catalyzed by [RuCl2(PPh3)3] to Give Polybenzimidazole Containing Ferrocenylene Groups
Authors: Yamaguchi Isao , Osakada Kohtaro , Yamamoto Takakazu , Katada Motomi
Published: May 2005

The 1 : 2 polycondensation of 3,3′,4,4′-biphenyltetramine and 1,1′-ferrocenedimethanol catalyzed by [RuCl2(PPh3)3] gives ferrocenylene-containing polybenzimidazole 1, (Im–Fc–CH2–O–CH2–Fc)n (Im = [5,5′-bi(benzimidazole)]-2,2′-diyl, Fc = 1,1′-ferrocenediyl). The reaction involves 1 : 2 condensation of 3,3′,4,4′-biphenyltetramine and 1,1′-ferrocenedimethanol to make two imidazole rings and subsequent intermolecular dehydrating coupling of two CH2OH groups to form the CH2–O–CH2 linkage. Polymer 1 is soluble in DMF and DMSO and has molecular weights, Mn = 2.1 × 104 and Mw = 4.5 × 104, determined by GPC (polystyrene standards). Extremely broad 1H NMR signals and results of SQUID measurements showing paramagnetism of 1 suggest the presence of Fe(III) centers in the polymer. The content of Fe(III) is estimated as approximately 20% based on the Mössbauer spectrum of 1. An equimolar reaction of 1,2-diaminobenzene and 1,1′-ferrocenedimethanol in the presence of the Ru(II) catalyst gives bis[1′-(benzimidazol-2-yl)ferrocen-1-ylmethyl] ether. The model compound shows reversible oxidation and reduction peaks assigned to the Fe(II)/Fe(III) redox, whereas the Polymer 1 undergoes oxidation and subsequent irreversible deprotonation to give the electrochemically inert polymer.
Calix[5]arene-Based Receptor for Dumb-Bell-Shaped C120
Authors: Haino Takeharu , Seyama Jun , Fukunaga Chigusa , Murata Yasujiro , Komatsu Koichi , Fukazawa Yoshimasa
Published: May 2005

We have developed calix[5]arene-based receptors for dumb-bell-shaped C120. The receptors encapsulate C120 with the high binding constants in o-dichlorobenzene.
Hydrophobic Vitamin B12. Part 20: Supernucleophilicity of Co(I) Heptamethyl Cobyrinate toward Various Organic Halides
Authors: Shimakoshi Hisashi , Maeyama Yasunori , Kaieda Takeshi , Matsuo Takashi , Matsui Eiki , Naruta Yoshinori , Hisaeda Yoshio
Published: May 2005

Heptamethyl cobyrinate, hydrophobic vitamin B12, was reduced to its Co(I) species by a reaction with sodium tetrahydroborate, which reacted with various organic halides, such as CH2Cl2, CHCl3, CCl4, CHBrCl2, CHBr3, CCl3CH3, CFCl3, and BrCH2CH2CH3, to form the corresponding alkylated complexes with dehalogenation. The alkylated complexes were characterized by elemental analyses and ESI-MS, and the photo-lability of the alkylated complexes was confirmed by the UV–vis absorption spectral change. The fashion for cleavage of the cobalt–carbon bond under irradiation with visible light was investigated by an ESR spin-trapping technique. The redox behavior of a series of alkylated complexes was investigated by cyclic voltammetry. The alkylated complexes showed an irreversible reduction peak at −1.21 to −1.29 V vs Ag–AgCl, which showed cleavage of the cobalt–carbon bond by electrolysis.
Arbutin Flow-Injection Analysis Using a Printed Circuit-Board Waste Modified Screen-Printed Electrode
Authors: Shih Ying , Zen Jyh-Myng , Senthil Kumar Annamalai , Huang Yu-Neng
Published: May 2005

A copper-metal enriched printed-circuit board waste modified screen-printed electrode has been demonstrated for the sensitive electroanalysis of a tyrosinase biosynthesis-inhibiting cosmetic agent, arbutin by flow-injection analysis.
Glycosyl Phosphonium Halide as a Reactive Intermediate in Highly α-Selective Glycosylation
Authors: Kobashi Yohei , Mukaiyama Teruaki
Published: May 2005

Highly α-selective glycosylations of several glycosyl acceptors with 2,3,4,6-tetra-O-benzyl-d-glucopyranosyl bromide (4) proceeded smoothly in the presence of tri(1-pyrrolidino)phosphine oxide in CH2Cl2 at room temperature or in refluxing CHCl3 via glycosyl phosphonium bromide intermediates and the corresponding disaccharides were afforded in good yields with high selectivities. Further, the one-pot glycosylation starting from glycosyl acetate using iodotrimethylsilane and phosphine oxide also proceeded efficiently in CH2Cl2 at room temperature to give the corresponding disaccharides, although this one-pot synthesis of α-glycoside via in situ anomerization procedure is considered difficult because glycosyl halide reacts with trimethylsilyl acetate easily to regenerate glycosyl acetate, a starting glycosyl donor.
Secondary Structural Studies of Biosynthetic Polypeptides with a Repeating Sequence of Glycine-Rich Sequence of Spider Dragling Silk
Authors: Fukushima Yasumasa , Nakajima Hiroshi
Published: May 2005

Polypeptides with a repeating sequence of glycine-rich sequence of spider dragline silk were synthesized in E. Coli. The polypeptide in the solid state formed a β-sheet structure which exists in crystalline region of spider silk.
Homogeneous Catalysis in Liquefied Gas. Complex-Catalyzed Selective and Direct Conversion of Propane to Butanal at Room Temperature
Authors: Sakakura Toshiyasu , Ishiguro Kouji , Okano Makoto , Sako Takeshi
Published: May 2005

Homogeneous catalysis in liquefied gas proves to be a promising approach to functionalize gaseous alkanes selectively; upon illumination, RhCl(CO)(PMe3)2 catalyzes carbonylation of liquefied propane at room temperature to produce butanal with high regioselectivity.
Synthesis and Properties of Bis(ethyleneseleno)tetrathiafulvalene (BES-TTF) and Diselenolotetrathiafulvalene (DS-TTF) as Novel Electron Donors
Authors: Jigami Tetsuya , Takimiya Kazuo , Aso Yoshio , Otsubo Tetsuo
Published: May 2005

The title selenocycle-fused tetrathiafulvalene derivatives, BES-TTF and DS-TTF have been synthesized as novel electron donors, and their conductive charge-transfer complexes have been studied. All complexes of the BES-TTF compound with TCNQ, ClO4, and PF6 showed very high conductivities of the order of 102 S cm−1 as well as metallic temperature-dependent behavior.
Synthesis of a New Pd(II) Complex with One hfac-O,O′ and One hfac-Monoxime-C,N as Ligands; Unexpected C–O Bond Formation between C3-Bonded hfac and N-Bonded Monoxime
Authors: Okeya Seichi , Taniguchi Kayo , Nishimura Jyunko , Kusuyama Yoshiaki , Nagasawa Isoroku , Kushi Yoshihiko
Published: May 2005

Reaction of [Pd(hfac)2] with monoximes gave new Pd complexes with one hfac-O,O′-chelate and one hfac-oxime-C,N-chelate, , in which a C–O bond was formed between the C3-bonded hfac and the N-bonded monoxime.
Direct Observation of Acid-Base Interaction by Means of Mass Spectrometry for Clusters
Authors: Mochizuki Shunsuke , Usui Yoshiharu , Wakisaka Akihiro
Published: May 2005

The acid-base interaction could be visualized in the mass spectra of clusters isolated from solutions. The butyric acid-pyridine acid-base system in acetonitrile afforded clusters in which (butyric acid)1(pyridine)1 complex behaves like an unit species; on the contrary, the butyric acid-pyrazine system afforded clusters in which butyric acid clusters, (butyric acid)n, hold main structure. This clear difference is reasonably related with the relatively strong and weak acid-base interactions.
Observation of Intramolecular Hydrogen Bonds of o-Fluorophenol Ions by Using Autoionization Detected Infrared Spectroscopy
Authors: Fujii Asuka , Iwasaki Atsushi , Mikami Naohiko
Published: May 2005

Intramolecular hydrogen-bonded OH stretching vibration for o-fluorophenol ion is observed by using a newly developed technique for infrared spectroscopy of isolated molecular ions.
Palladium-Catalyzed Oxidative Cross-Coupling of 2-Phenylphenols with Alkenes
Authors: Miura Masahiro , Tsuda Takatoshi , Satoh Tetsuya , Nomura Masakatsu
Published: May 2005

2-Phenylphenols react with alkenes such as acrylate esters in the presence of a palladium-copper catalyst system under air to give the corresponding 6-substituted 6H-dibenzo[b,d]pyran derivatives.
Synthesis of Polydiacetylene-Based Ladder Polymer
Authors: Matsuzawa Hiroshi , Okada Shuji , Matsuda Hiro , Nakanishi Hachiro
Published: May 2005

A novel polydiacetylene (PDA) was prepared from the monomer having two butadiyne parts linked by a chain of methylene units. Polymerization is solid state was performed by UV or γ-ray irradiation. From 13C NMR spectra measured using CP/MAS technique, the structure of the ladder polymer composed of two PDAs linked by methylene chains was confirmed. By X-ray diffraction experiment, crystallinity was found to be preserved even for the ladder polymer.
Removal of As(III) and As(V) by a Porous Spherical Resin Loaded with Monoclinic Hydrous Zirconium Oxide
Authors: Suzuki Toshishige M , Bomani John O , Matsunaga Hideyuki , Yokoyama Toshiro
Published: May 2005

A porous spherical resin loaded with monoclinic hydrous zirconium oxide was prepared and the physico-chemical properties were examined. The zirconium loaded resin showed a strong retainment of As(III) and As(V). The removal of low concentration of arsenic to meet the demand of industrial effluent standard (0.1ppm, ppm = mg dm−3) was achieved by the column process with the present resin.
Anionic Ring Opening Polymerization of Octamethyltetrasilacyclopentane
Authors: Sanji Takanobu , Hanao Hiroyuki , Sakurai Hideki
Published: May 2005

Poly(1,1,2,2,3,3,4,4-octamethyltetrasilanylenemethylene) of a highly regulated structure was synthesized by anionic ring opening polymerization of octamethyltetrasilacyclopentane. In this polymerization process, α-silyl carbanions play an important role. In this polymer, delocalization in the ground state is much important in the σ-conjugation between the tetrasilanylene units via the methylene units.
Photoluminescence Properties of the Vanadium Silicalite-1 Catalyst and Its Photocatalytic Reactivity for the Reduction of NO with Propane
Authors: Higashimoto Shinya , Zhang Shu Guo , Yamashita Hiromi , Matsumura Yasuyuki , Souma Yoshie , Anpo Masakazu
Published: May 2005

The vanadium silicalite-1 catalyst (VS-1) has been found to include highly dispersed V-O moieties having a tetrahedral coordination in C3v symmetry, which exhibits a photoluminescence spectrum attributed to the radiative decay from the charge transfer excited state. Also, the photocatalytic reduction of NO into N2 was found to proceed much more efficiently in the presence of propane than with the direct photocatalytic decomposition of NO without propane. The dynamic quenching of the photoluminescence spectrum by the addition of NO and propane indicate that the excited state of the V-O moieties plays a significant role in this photocatalytic reaction.
Analytical Applications and Catalytic Activities of Electrodeposited Thallic Oxide Films
Authors: Liu Junfu , Zhang Lingang , Yang Kongzhang , Lu Zuhong
Published: May 2005

Thallic oxide (Tl2O3) were electrodeposited onto indium tin oxide (ITO) conducting glass substrates in alkaline solutions. It has a high catalytic activity for the anodic oxidation of sulfite (SO32−) and thiosulfate (S2O32−) anions. Also it can be used for electroanalysis of nitrite ions (NO2−) with an excellent stability and a detection limit of 4.0 × 10−6 mol/dm3.
Enantio-differentiating Hydrogenation of Methyl Acetoacetate over Asymmetrically Modified Supported Nickel Catalyst Prepared from Nickel Acetylacetonate
Authors: Osawa Tsutomu , Mita Shinya , Iwai Akiko , Miyazaki Takafumi , Takayasu Osamu , Harada Tadao , Matsuura Ikuya
Published: May 2005

Various supported nickel catalysts were prepared from nickel acetylacetonate in a solvent-free condition, and then these catalysts were modified in the solution containing tartaric acid and NaBr. Enantio-differentiating hydrogenation of methyl acetoacetate was carried out over the resulting tartaric acid-NaBr-modified supported Ni catalysts. Maximal optical yield 86% was attained when zeolite was used as a support.
Reductive Dehalogenation of Carbon Tetrachloride by Sodium Dithionite
Authors: Rodríguez Juan Carlos , Rivera Mario
Published: May 2005

Addition of Sodium dithionite (Na2S2O4) to aqueous carbon tetrachloride solutions (∼650 mg/L) resulted in CCl4 concentrations lower than 2.5 mg/L after 2.5 h and in undetectable concentrations after 4-5 h of reaction. The main product of the reductive dehalogenation of CCl4 by Na2S2O4 was found to be the trichloromethanesulfinate (CCl3SO2−) anion.
Preparation and Assembled Structure of Dipolar Dendrons Based Electron Donor/Acceptor Azobenzene Branching
Authors: Yokoyama Shiyoshi , Nakahama Tatsuo , Otomo Akira , Mashiko Shinro
Published: May 2005

Dipolar dendrons constructed of electron donor/acceptor azobenzene branches and aliphatic exteriors have been synthesized. They formed the polar assemblies in a matrix of fatty acid and showed a significant increase in second-order nonlinear optical activity with an increse in branching.
Vapour-Phase Selective Oxidation of 4-Methylanisole to Anisaldehyde over V2O5/Ga2O3-TiO2 Catalyst
Authors: Reddy Benjaram M , Ganesh Ibram , Chowdhury Biswajit
Published: May 2005

The vapour phase partial oxidation of 4-methylanisole to p-anisaldehyde was investigated over binary oxide supported vanadium oxide catalysts at 623-748 K under normal atmospheric pressure. Among various catalysts the V2O5/Ga2O3-TiO2 effectively performed this reaction with high activity and selectivity.
Oxo-single-bridged and Oxo-carboxylato-double-bridged Diruthenium(III) Complexes of Tris(2-pyridylmethyl)amine
Authors: Koshi Chikako , Umakoshi Keisuke , Sasaki Yoichi
Published: May 2005

An oxo single-bridged and a series of oxo-carboxylato di-bridged diruthenium(III) complexes, [Ru2(μ-O)Cl2(tpa)2]3+ and [Ru2(μ-O)(μ-RCOO)(tpa)2]3+ (tpa = tris(2-pyridylmethyl)amine; R = CH3, C2H5, C3H7, and C6H5), show comparative structural, redox, magnetic and spectroscopic properties.
Iterative Amination Strategy in the Synthesis of Peptidomimetics
Authors: Frost Christopher G , Mendonça Paul
Published: May 2005

An iterative palladium catalysed cross-coupling reaction of aryl bromides with amines has been employed in the preparation of novel peptidomimetics. This is a versatile strategy with which we can demonstrate the principle of library synthesis by using a diverse range of coupling partners.
Characterization of Active Center of a Non-Heme Chloroperoxidase by X-Ray Absorption Fine Structure
Authors: Shen Run-nan , Kou Yuan , Zhang Fen , Niu Jian-zhong , Li Shu-ben
Published: May 2005

XAFS studies on this non-heme chloroperoxidase reveal that its Fe core is in a saturated six-coordinate, octahedral environment with four planer N atoms and two axial S atoms. The active site is very similar to Fe porphyrine center in P450 oxidase, but the coordinated N atoms come from amino acids of polypeptides or other molecules, but not porphyrin.
Photochemical C–C Bond Formation from Chlorobenzene Mediated by [Pd(PPh3)4]
Authors: Tsubomura Taro , Ishikura Akira , Hoshino Kenta , Narita Hiroki , Sakai Ken
Published: May 2005

Photo-irradiation upon the chlorobenzene solution of [Pd(PPh3)4] affords trans-[PdCl2(PPh3)2] and a mixture of chlorobiphenyls. In the presence of zinc and organic amines, the catalytic production of chlorobiphenyls mediated by the palladium complex was observed with irradiation of light.
Homopyrimidine Oligonucleotides Modified by a Pyrenylmethyl Group at the Terminal Position: Enhanced Fluorescence upon Binding to Double Helical DNA
Authors: Yamana Kazushige , Kumamoto Satoshi , Nakano Hidehiko
Published: May 2005

Oligopyrimidines labeled by a pyrenylmethyl group at the terminal position exhibit high affinity for double helical DNA and enhanced fluorescence upon hybridization.
Remote Oxygen Migration Reaction between Sulfur Atoms in 1,4-Bis(methylthio)benzene Derivatives: Possible Formation of Bis(dithia dication) Dimer as an Intermediate
Authors: Kobayashi Kenji , Obinata Takanobu , Furukawa Naomichi
Published: May 2005

The oxygen migration reaction between sulfur atoms in the monooxide of 1,4-bis(methylthio)benzene preceeds in the presence of CF3CO2H. The reaction of 1,4-bis(methylthio)benzene with its bis-sulfoxide also gives the corresponding monooxide at room temperature. A two-point bis(dithia dication) dimer is proposed as an intermediate.
DNA Cleaving Activity and Cytotoxic Activity of Ferricenium Cations
Authors: Tamura Hiroshi , Miwa Masahiro
Published: May 2005

Ferricenium cations showed excellent DNA cleaving activity and cytotoxic activity. Such activities depend on the acyl group introduced into the cyclopentadienyl ring.
Reaction of Hydrosilanes with Lithium. Formation of Silole Anions from 1-Methylsilole via Carbodianion
Authors: Wakahara Takatsugu , Ando Wataru
Published: May 2005

Three different types of silacyclopentadienyl anions have been obtained in the reduction of 1-methylsilole 1 with excess lithium. Treatment of lithiated solution with dimethylchlorosilane gave 2,5-bis(dimethylsilyl)silole derivatives 3a and 3b, and with trimethylchlorosilane gave 1-trimethylsilyl-1-methylsilole derivative 4 at an early stage, and 1,1-bis(trimethylsilyl)silole derivative 8 at a late stage. Silole 1,1-dianion 7 has been formed via silole 2,5-dianion 2 and silole 1-anion 5.
Photorefractive Effect of Liquid Crystal Polymer Poly 4-methacryloyloxyhexyloxy(4′-nitrobenzylidene)aniline
Authors: Sasaki Takeo , Hamada Shyuichi , Ishikawa Yuichi , Yoshimi Takeshi
Published: May 2005

The photorefractive effect of the liquid crystal polymer, poly 4-methacryloyloxyhexyloxy(4′-nitrobenzylidene)aniline doped with (diethylamino)benzaldehyde diphenylhydrazone (DEH) and 2,4,7-trinitro-9-fluorenone (TNF), was investigated using a two-beam coupling experiment. A diffraction efficiency of ∼5% was obtained under an applied electric field of 20∼30 V/μm.
Stereoselective Synthesis of the C1-C7 Segment of (+)-Discodermolide
Authors: Miyazawa Masahiro , Oonuma Satoshi , Maruyama Kimiyuki , Miyashita Masaaki
Published: May 2005

A new and highly stereoselective synthesis of the C1-C7 segment of (+)-discodermolide, the marine natural product having the potent immunosuppressive activity, is described in which the stereospecific methylation of γ,δ-epoxy acrylate with trimethylaluminum and the intramolecular conjugate addition of an acetal alkoxide anion are involved as key steps.
ESR Study of Iron(III) in N-Terminal Lobe of Hen Ovotransferrin
Authors: Kawabata Teruyuki , Ma Yuxiang , Okada Shigeru
Published: May 2005

Hen ovotransferrin was digested by trypsin and the N-terminal lobe fragment was prepared by gel filtration and ion-exchange chromatography. Fe(III) complex of the N-terminal fragment had a LMCT absorption at 462 nm in UV/Vis spectrum. ESR spectrum of the iron(III) complex showed a g = 4.2 signal with doubly split ones in the lower magnetic field and a weak g = 8.9 signal. The iron was similar high-spin ferric iron with near rhombicity to the whole ovotransferrin, using a S = 5/2 spin Hamiltonian.
Synthesis of 9-Deoxycotylenol Derivatives and Their Seed Germination-Stimulating Activity
Authors: Li Feng , Kato Nobuo , Mori Akira , Takeshita Hitoshi , Sassa Takeshi
Published: May 2005

9-Deoxy-15-methoxymethoxycotylenol and 9-deoxy-19-methoxymethoxycotylenol were synthesized to clarify a role of the 9α-hydroxyl of cotylenol, a common aglycon of cotylenins possessing potent plant growth-regulating activities. Both of the 9-deoxycotylenol derivatives stimulated germination of lettuce seeds and therefore it has been clarified that the 9α-hydroxyl of cotylenol is not essential for the biological activities.
Vanadium-containing Silsesquioxane-catalyzed Photo-assisted Oxidation of Hydrocarbons
Authors: Wada Kenji , Nakashita Masashi , Yamanoto Akihiro , Wada Hiroshi , Mitsudo Take-aki
Published: May 2005

The activity of a vanadium-containing oligosilsesquioxane towards the photo-assisted catalytic oxidation of benzene and cyclohexane was investigated for the first time in order to examine its ability as an organic solvent-soluble analogue of silica-supported oxide catalysts. An oligosilsesquioxane, 1b, showed excellent activity toward the selective photooxidation of cyclohexane into cyclohexanone and cyclohexanol (TON ∼ 20, at 305 K, 6 h).
Preparation, Properties, and Structures of [IrCl(diphosphine)]2 (diphosphine = (R)-BINAP and BPBP)
Authors: Yamagata Tsuneaki , Iseki Aika , Tani Kazuhide
Published: May 2005

[IrCl(diphosphine)]2 {diphosphine = BINAP (1a) and BPBP (1b)} were obtained as extremely air- and moisture-sensitive crystals. The structure of 1a has been determined by X-ray analysis. Complex 1a reacted easily with two equivalents of triphenylphosphine to give IrCl(binap)(PPh3) 2a quantitatively. Complexes 1a and 1b can activate RO–H groups easily and catalyze transfer hydrogenation of alkynes in methanol. On the contrary 2a does not react with methanol even at 55 °C.
Chemical Tools for Detection of Intracellular pH-Change in Halobacteria
Authors: Urano Hikaru , Mizukami Taku , Tsujimoto Kazuo
Published: May 2005

Time-dependent pH-change in halobacteria was observed with fluorescent dye. Mechanical improvement of a cell holder in a fluorescence spectrometer enabled us to measure the intracellular pH-change that proved different from the extracellular change. Upon irradiation, the extracellular pH of the strain initially changed into higher value and subsequently reverted to lower value until irradiation ceased, whereas the intracellular pH monotonously increased for freshly prepared cells. Nevertheless, the pH-changes in liposome with bacteriorhodopsin were complementary each other.
A Mechanistic Study for 4A1 Antibody-Catalyzed Hydrolysis : Detection of Acyl Intermediate
Authors: Wada Yumiko , Sudo Yukio , Ono Mitsunori
Published: May 2005

Recent study identified a hydrolytic abzyme 4A1, that has a significant rate enhancement in hydrolysis of carbonate substrates differing from the inducing hapten in structure around the scissile bond. Kinetic investigation suggested the existence of other affinity elements for potential substrate side chains. This paper presents further study of 4A1-catalyzed hydrolysis based on detection of an acyl intermediate in the hydrolytic reaction.
Preparation of Soluble AlN Precursors in a LiAlH4-CH3NH2·HCl-(CH3)2NH·HCl System
Authors: Koyama Seiichi , Saito Yasuo , Sugahara Yoshiyuki , Kuroda Kazuyuki
Published: May 2005

Novel AlN precursors have been prepared by reactions in a LiAlH4-CH3NH2·HCl-(CH3)2NH·HCl system with several nominal CH3NH2·HCl : (CH3)2NH·HCl (M : D) ratios (M : D = 4 : 1, 6 : 1 and 8 : 1). Considerable amounts of precursors were soluble in both tetrahydrofuran and benzene. Soluble precursors consist of polymeric/oligomeric species possessing both [H2AlNMe2] and [HAlNMe] units, and ring-type (H2AlNMe2)3 was also present only if M : D = 4 : 1. The precursors were converted into single-phase AlN with relatively high ceramic yields (up to 58 %) by pyrolysis at 1600 °C under Ar.
Air Oxidation of Sulfides to Sulfoxides Using BiBr3-Bi(NO3)3 as a Binary Catalyst
Authors: Komatsu Naoki , Uda Masato , Suzuki Hitomi
Published: May 2005

Selective air oxidation of sulfides to sulfoxides was accomplished with a binary catalytic system, BiBr3-Bi(NO3)3, in high yields under aerial ambient conditions. This oxygenation requires neither an aldehyde nor a transition metal complex.
Solid Phase Synthesis of Oligonucleotides Bearing Phosphate and Thiophosphate at Their 3′-Termini
Authors: Kumar P , Gupta K C , Rösch R , Seliger H
Published: May 2005

Controlled pore glass (CPG) containing mercaptoalkyl groups allows the synthesis of oligonucleotides bearing 3′-phosphate or thiophosphate function during final deprotection.
PbBr-Based Layered Perovskite Containing Chromophore-Linked Ammonium Molecule as an Organic Layer
Authors: Era Masanao , Maeda Koji , Tsutsui Tetsuo
Published: May 2005

Oriented thin films of new organic-inorganic layered perovskites having a quantum-well structure combined with PbBr-based semiconductor layer and a chromophore-linked ammonium molecule layer were formed in a self-organizing manner by a simple spin-coating from the solutions of stoichiometric amounts of lead bromide PbBr2 and an ammonium bromide linked with a chromophore such as naphthalene and azobenzene.
The Structural Change Caused by Temperature-Induced Metal-to-Ligand Charge Transfer in [Pd(HBQD)2]TCNQ(HBQD = 1,2-Benzoquinonedioxime)
Authors: Sakai Ken-ichi , Kitagawa Hiroshi , Mitani Tadaoki , Yamashita Masahiro
Published: May 2005

The crystal structure of a charge-transfer complex, [Pd(HBQD)2]TCNQ (TCNQ = tetracyanoquinodimethane, HBQD = 1,2-benzoquinonedioxime) has been studied at 295 K and 110 K by X-ray diffraction. The bond-length change in the ligand π-conjugated system of Pd(HBQD)2 was consistent with the nodal property of the lowest unoccupied molecular orbital. This supports the temperature-induced charge transfer from the Pd ion to the π* antibonding orbital of ligand HBQD.
High-performance Liquid Chromatographic Separation of Monosaccharides and Disaccharides on Stationary Phases Prepared from Polystyrene-based Resins and Tertiary Diamines
Authors: Masuda Takako , Nishimura Yukihiro , Tonegawa Masami , Kitahara Keiichi , Arai Sadao , Yamashita Junzo , Takai Nobuharu
Published: May 2005

High-performance liquid chromatographic separation of monosaccharides and disaccharides was successfully carried out with novel anion-exchange stationary phases prepared from (CH3)2N-(CH2)n-N(CH3)2 and porous particles of chloromethylated styrene-divinylbenzene copolymer coupled with a pulsed amperometric detector.
Intramolecular Cyclization of 1,2-Distyrylbenzene via Cation Radical Generated by Photoinduced Electron Transfer
Authors: Kojima Ryuji , Shiragami Tsutomu , Shima Kensuke , Yasuda Masahide , Majima Tetsuro
Published: May 2005

Photoamination of 1,2-distyrylbenzene (1a) with NH3 in the presence of p-dicyanobenzene has been investigated. 1-Benzyl-3-phenyl-1,2,3,4-tetrahydroisoquinoline (2a) and 1-amino-3-benzyl-2-phenylindan (3a) were formed as a consequence of the nucluophilic additions of NH3 to 1a+· and indan-type cation radical (4+·) generated by transformation of 1a+·.
Zirconocene Catalyzed Dehalogenation of Aromatic Halides by Alkylmagnesium Reagents
Authors: Hara Ryuichiro , Sun Wen-Hua , Nishihara Yasushi , Takahashi Tamotsu
Published: May 2005

When aromatic halides were treated with alkylmagnesium reagents (which have β-hydrogens) and a catalytic amount of zirconocene dichloride, dehalogenation proceeded smoothly in high yields. The stoichiometric dehalogenation using dialkylzirconocenes also proceeded with high selectivities.
Preparation of Hydrodesulfurization Catalysts by Impregnation of Alumina with New Heteropolycompounds
Authors: Griboval Anne , Blanchard Pascal , Payen Edmond , Fournier Michel , Dubois Jean-Luc
Published: May 2005

A novel preparation method of hydrodesulfurization catalysts with Keggin type heteropolyanions as starting material has been developed. This preparation involves a reduction step of the heteropolyanions within the impregnating solution, in order to achieve high Co/Mo ratio. Catalysts prepared from such solutions were proved to be superior to conventional catalysts, in terms of thiophene HDS activity.
Dehydration of 2-Propanol over Molybdenum Oxide Treated with Hydrogen
Authors: Matsuda Takeshi , Hirata Yasuyoshi , Sakagami Hirotoshi , Takahashi Nobuo
Published: May 2005

Dehydration of 2-propanol was carried out at 398 K using molybdenum oxides as a catalyst. The parent MoO3 exhibited a low activity. H2 reduction at 623 K increased the dehydration activity. After the reduction for 4 h, the MoO3 became more active than USY zeolites, although the catalytic activity of MoO3 declined with time on stream. We suggest that the acidity of MoO3 was enhanced by H2 reduction at 623 K.
Ion and Radical Pair Generation in Tribromoacetophenone
Authors: Morlet-Savary F , Fouassier J P , Tomioka Hideo , Sumiyoshi Iwao , Takimoto Yasuyuki
Published: May 2005

Investigation of the excited state processes in a bromo acetophenone has been carried out by using time resolved laser spectroscopy techniques. The generation of Br2•− is reported for the first time and supports the primary formation of an ionic and a radical pair.
Paired Electrosynthesis of a Nitrone
Authors: Li Wei , Nonaka Tsutomu
Published: May 2005

Dibutyl N-hydroxylamine was oxidized by WO42−/WO52−/ and BR−/Br2 redox mediators at cathode and anode, respectively. The corresponding nitrone, N-butylidenebutylamine N-oxide, was prepared at the both electrodes in divided and undivided cells. The paired electrosynthesis of the nitrone could be realized with current efficiencies higher than 180%.
Synthesis of 1-Nonene from Decanoic Acid by Polymer-Bound Palladium Complexes
Authors: Tanaka Satoshi , Shimizu Kenji , Yamamoto Iwao
Published: May 2005

(phCN)2PdCl2 or Pd(OAc)2 was immobilized on polyorganosiloxane bearing phosphine group as the support. The catalytic activity of polymer-bound palladium complex revealed higher activity and selectivity than the homogeneous catalyst for the synthesis of 1-nonene from decanoic acid.
Ion Concentration at the Membrane Surface Obtained from the Membrane Potential and Transition of Ion Cluster Structure in Perfluorocarboxylate Ion Exchange Membrane System
Authors: Nomura Kazuo , Koga Tsutomu
Published: May 2005

The fast step and the subsequent slow step have been observed in the time course of the membrane potential in response to pH jump in the perfluoro carboxylate ion-exchange membrane-aqueous NaCl system. Using the Donnan potential obtained by separation of the two steps, the ion concentration at the membrane surface has been estimated. A change in the ion-cluster structure in the membrane has caused the plot of the surface concentration vs. pH in the external solution to break.
First Total Synthesis of (+)-Chrysanthemol
Authors: Chen Yonggang , Xiong Zhaoming , Zhou Gang , Yang Jiong , Li Yulin
Published: May 2005

The first total synthesis of (+)-chrysanthemol (1) has been described starting from (+)-dihydrocarvone (4). The features of our synthesis are the high yield introduction of C3-C4 double bond into eudesmane skeleton and rearrangement of epoxide to allylic alcohol promoted by BF3·OEt2-Bu4NI reagent. In our synthesis, (+)-α-eudesmol (5) has been used as a key intermediate.
Enhancing the Selectivity of Molecularly Imprinted Polymers
Authors: McNiven Scott , Yokobayashi Yohei , Cheong Soo Hwan , Karube Isao
Published: May 2005

The selectivity of a molecularly inprinted polymer (MIP) was substantially enhanced by inactivating the non-specific binding sites distributed within the polymer. Treatment of the polymer with varying amounts of methyl iodide in the presence of the template molecule resulted in stronger binding of the template and more effective separation from similar steroids.
Self-Assembly of Alkyl Substituted Schiff Base and Its Cu(II) Complex Observed on Solution–Graphite Interface by Scanning Tunneling Microscopy
Authors: Qian Pu , Nanjo Hiroshi , Sanada Norio , Yokoyama Toshiro , Suzuki Toshishige M
Published: May 2005

Self-assembled monolayer of Schiff base ligand, N-octadecylsalicylaldimine (C18Sal) has been observed by scanning tunneling microscope on the solution–graphite interface and the molecular geometry has been assigned. The molecular pattern of the Schiff base immediately changed upon addition of Cu(II) associated with in situ complexation and formation of a new molecular framework.
Fluorescence Measurement of 3,5-Dimethoxyphenol Radical Cation Generated by Pulse Radiolysis in 1,2-Dichloroethane
Authors: Ichinose Nobuyuki , Tojo Sachiko , Majima Tetsuro
Published: May 2005

Radical cation of 3,5-dimethoxyphenol in the excited state generated in 1,2-dichloroethane solution by the tandem irradiation of 28-MeV electron and 532-nm laser pulses emitted fluorescence around 600–750 nm with a quantum yield of 2.0 × 10−3.
Novel Polydiacetylenes Containing Crown Ether Groups
Authors: Shimada Satoru , Masaki Atsushi , Hayamizu Kikuko , Matsuda Hiro , Okada Shuji , Nakanishi Hachiro
Published: May 2005

Polydiacetylenes containing crown ethers in the substituent were synthesized by the solid-state polymerization of the corresponding diacetylenes derived from 1,10-pentacosadiynoic acid in the manner of 1,4-addition.
Facile Formation and Dissociation Behaviour of C–C Bond Resulted from the Nucleophilic Attack of Carbanions on a Carbonyl Carbon in [Pt(hfac)2]
Authors: Okeya Seichi , Hashimoto Masato , Nakamura Fumiko , Kusuyama Yoshiaki , Kobayashi Mako , Arakawa Ryuichi
Published: May 2005

[Pt(hfac)2] (hfac: hexafluoroacetylacetonate) reacts with MeNH2 in CH2Cl2/MeOH to give an –NHMe adduct complex on one of the carbonyl carbons, (MeNH3)[Pt(hfac)(hfac–NHMe)] 1 which is a tetrahedral intermediate of a Schiff base complex, [Pt(CF3COCHC(Nme)CF3)2] 2. Complex 1 activates H2O, MeOH, MeNO2 or acetone in solution to form the corresponding conjugate base adducts. The C–C bond in –CH2NO2 adduct 6, easily cleaves and generates nitromethane in solution.
Bis(μ-oxo)(μ-hydroxo)triiron(III) and (μ-oxo)(μ-hydroxo)diiron(III) Core Complexes with Tripodal Ligands Having a Terminal Carboxylate Group
Authors: Furutachi Hideki , Ohyama Yuya , Tsuchiya Yasutaka , Hashimoto Koji , Fujinami Shuhei , Uehara Akira , Suzuki Masatatsu , Maeda Yonezo
Published: May 2005

The tripodal ligands (6Me2-BPG and BPG) containing the carboxylate donor afford two types of Fe2(O)(OH) and Fe3(O)2(OH) core complexes, depending upon the methyl-substituent effect on the 6-position of the pyridyl ring.
Use of 2-Cyano-1-t-butylethyl or 2-Cyano-1-(1,1-diethyl-3-butenyl)ethyl as a Phosphorus Protecting Group in Oligonucleotide Synthesis via in situ Phosphoramidite Methods
Authors: Kitamura Akinori , Horie Yoji , Yoshida Tadao
Published: May 2005

2-Cyano-1-t-butylethyl or 2-cyano-1-(1,1-diethyl-3-butenyl)ethyl 3′-O-phosphorimidazolidite of 5′-O-protected nucleoside was prepared in situ by the use of 2-cyano-1-t-butylethyl or 2-cyano-1-(1,1-diethyl-3-butenyl)ethyl phosphorobisimidazolidite as a new phosphitylating reagent. The phosphorimidazolidites were found to be key intermediates for preparing 5′-O-protected nucleoside 3′-O-monoalkylphosphoramidites in situ useful in the solid-phase oligonucleotide synthesis, and for synthesizing conveniently 3′-OH free dinucleoside phosphates and phosphorothioates in solution.
A Mixed-Valence Mn(II,III) Complex with a 2D Structure: Crystal Structure and Magnetic Property of K[Mn2(µ-CrO4)2(µ-OH)2]
Authors: Oshio Hiroki , Kikuchi Kazuhiro , Ito Tasuku
Published: May 2005

Reaction of MnSO4·4H2O with K2CrO4 in water yielded highly crystalline black solids, which was chracterized to a 2D mixed valent Mn(II,III) complex, potassium di-μ-chromato-di-μ-hydroxo-dimanganate (1-) K[Mn2(µ-CrO4)2(µ-OH)2] (1).
A Novel Cis–Trans Photoisomerization of Vinylidenecyclopropanes via Excited Singlet and Triplet States
Authors: Mizuno Kazuhiko , Sugita Hikaru , Hirai Takayoshi , Maeda Hajime
Published: May 2005

Photoisomerization of cis- and trans-1-diarylvinylidene-2,3-dimethylcyclopropanes is described. The formation of different photostationary state mixtures of cis and trans isomers generated by direct and triplet-sensitized photoreactions clearly shows that the photoisomerization proceeds via their excited singlet and triplet states, respectively.
Low-Temperature Magnets M[N(CN)2]2(pyrimidine) (M = Fe and Co) with a 3-D Network
Authors: Kusaka Takaharu , Ishida Takayuki , Hashizume Daisuke , Iwasaki Fujiko , Nogami Takashi
Published: May 2005

X-Ray crystal structure analyses reveal that the title complexes have a 3-D network, in which N(CN)2− and pyrimidine contribute µ-1,5-bridged 2-D and µ-1,3-bridged 1-D structures, respectively. Magnetic measurements indicate that the Fe and Co complexes have spontaneous magnetizations below the transition temperatures of 3.2 and 1.8 K, respectively.
Sugar-Integrated “Supergelators” Which Can Form Organogels with 0.03–0.05% [g mL−1]
Authors: Luboradzki Roman , Gronwald Oliver , Ikeda Atsushi , Shinkai Seiji
Published: May 2005

It was found that methyl-4,6-O-p-nitrobenzylidene-α-d-galactopyranoside (1) and methyl-4,6-O-benzylidene-α-d-mannopyranoside (2), which are scarcely soluble in apolar solvents, act as “supergelators” when they are enforcedly dissolved above their bp’s in a sealed tube. The minimum gelator concentrations (Cmin) were 0.03–0.07% [g mL−1] which are one of the lowest concentrations achieved so far. The coupled study of TEM observation with partial solvent exchange established that the organogel stability is related to the superstructure in the fibril network constructed in specific solvents.
Characterization of Fe-Oxide Species Prepared onto ZSM-5 Zeolites and Their Role in the Photocatalytic Decomposition of N2O into N2 and O2
Authors: Higashimoto Shinya , Nishimoto Kazuhiko , Ono Takehiko , Anpo Masakazu
Published: May 2005

Investigations on the effect of the local structures on Fe-ZSM-5 zeolites by means of ESR, UV–Vis absorption and XRD measurements have shown that Fe-ZSM-5 with low Si/Al ratios includes highly dispersed Fe-oxides with tetrahedral and distorted tetrahedral coordinations, while the latter species could not be observed in Fe-ZSM-5 with high Si/Al ratios. Moreover, the photocatalytic decomposition of N2O into N2 and O2 was found to proceed on Fe-ZSM-5 having low Si/Al ratios with a good linearity against the UV-irradiation time and a good stoichiometry. It was also observed that the photocatalytic efficiency decreased when the Si/Al ratio was increased. These results clearly suggest that a highly dispersed distorted tetrahedrally coordinated Fe-oxide species plays a significant role in the photocatalytic decomposition of N2O into N2 and O2.
Ammonia Production Characteristics of Ru/Al2O3 Catalysts Using Hydrogen Permeable Membrane
Authors: Itoh Masahiro , Machida Ken-ich , Adachi Gin-ya
Published: May 2005

Ammonia production characteristics were performed on Ru–Al2O3 catalyst loaded on a Ag–Pd hydrogen permeable membrane in the temperature range from room temperature to 523 K under atmospheric pressure, by which the activation energy observed (33.1 kJ mol−1) was lower than the sole Ru–Al2O3 catalyst (66.8 kJ mol−1). Ammonia was formed over the membrane reactor even at room temperature due to the high reactivity of atomic hydrogen supplied from the membrane.
Surface Organometallic Chemistry of Tin: Grafting Reaction of Sn(CH3)4 in HY Zeolite Supercage
Authors: Wang Xuxu , Zhao Huixia , Lefebvre Frédéric , Basset Jean-Marie
Published: May 2005

Tetramethyltin reacts rapidly, even at low temperature, with the hydroxy groups in the supercages of HY zeolite, resulting in the formation of well-defined –Sn(CH3)3 fragments in the supercages. This reaction is very selective as there is no reaction with the hydroxy groups in the sodalite cages and prisms.
Low Molecular Weight Gelator Containing β-Diketonato Ligands: Stabilization of Gels by Metal Coordination
Authors: Hanabusa Kenji , Maesaka Yukinobu , Suzuki Masahiro , Kimura Mutsumi , Shirai Hirofusa
Published: May 2005

A low molecular weight gelator containing β-diketonato ligands was prepared from a derivative based on trans-(1R,2R)-diaminocyclohexane. Gels were converted to mechanically-robust and thermally-stable gels by complexation between β-diketonato ligands and divalent metal ions.
Novel Gelators of Bile Acid–Alkylamine Salt Prepared through a Combinatorial Library Approach
Authors: Nakano Kazunori , Hishikawa Yukio , Sada Kazuki , Miyata Mikiji , Hanabusa Kenji
Published: May 2005

A combinatorial library approach enables us to find new low molecular-weight organogelators composed of a bile acid–alkylamine salt; the gel phenomena are investigated by FT-IR spectroscopy, SEM, and X-ray crystallography.
J-aggregate Formation in Single-Layer Amphiphilic Spiropyran Langmuir–Blodgett Films
Authors: Tachibana Hiroaki , Yamanaka Yasushi , Sakai Hideki , Abe Masahiko , Matsumoto Mutsuyoshi
Published: May 2005

J-aggregate formation was observed in single-layer Langmuir–Blodgett films of an amphiphilic spiropyran when they were irradiated with UV light at room temperature. We have revealed that tree-like structures with many branches are formed, accompanying the J-aggregate formation, which consist of a number of crystalline J-aggregates.
Highly Soluble Fluorenyl-Substituted Poly(1,4-phenylenevinylene) for Bright and Efficient Blue–Green Light-Emitting Diode
Authors: Lee Sang Ho , Jang Bo-Bin , Tsutsui Tetsuo
Published: May 2005

Poly[2-(9′,9′-bishexylfluorenyl)-1,4-phenylenevinylene] (BHF-PPV), which contains 9,9-bishexylfluorene as a pendant group, was synthesized by the modified Gilch polymerization of the corresponding bischloromethyl-substituted benzene monomer. Light emitting device fabricated with BHF-PPV showed high electroluminescence efficiency with low turn-on voltage.
Synthesis of Amorphous Diarylethenes Having Diphenylethenyl Substituents
Authors: Kim Myeong-Suk , Kawai Tsuyoshi , Irie Masahiro
Published: May 2005

1,2-Bis(2-methyl-1-benzothiophen-3-yl)perfluorocyclopentene derivatives having diphenylethenyl substituents at 6- and 6′-positions of the benzothiophene rings were synthesized. The mono and disubstituted derivatives formed an amorphous state and the glass transition temperatures were observed at 67 °C and 92 °C, respectively. Reversible photocyclization reactions were observed in the amorphous state.
A Simple Synthesis and the Crystal Structure of a Novel Tetranuclear Diorganotin Compound
Authors: Dey Dilip Kumar , Saha Manas Kumar , Mitra Samiran , Bansal Raj Kumar , Dahlenburg Lutz
Published: May 2005

The tetranuclear dimethyltin(IV) complex (L)SnMe2(µ3-O)(SnMe2)2(µ3-O)SnCl2Me2, which was obtained from Me2SnCl2 and the tetradentate Schiff base ligand N-2-[3′-(methoxysalicylideneimino)benzyl]-3′-methoxysalicylideneimine (H2L) avoiding strictly moisture-free conditions, displays one seven and three five-coordinate dimethyltin moieties bridged by two µ3-oxo groups as the basic structural features. Retention of solid state structure in solution is indicated by NMR spectra.
Lithium Magnesium Manganese Oxides Prepared from Mg-Birnessite or Mg-Todorokite by a LiNO3 Flux Method
Authors: Yang Xiaojing , Kanoh Hirofumi , Tang Weiping , Liu Zong-huai , Ooi Kenta
Published: May 2005

Layered and fibrous crystals of spinel-type lithium magnesium manganese oxide have been synthesized from Mg-containing birnessite and todorokite precursors respectively by a topotactic reaction in a LiNO3 flux at 400 °C.
Reaction of Vinyltitanium(IV) Species Prepared by the Alkylation of Titanium–Vinylcarbene Complexes
Authors: Takeda Takeshi , Saeki Naoko , Takagi Yasuhiro , Fujiwara Tooru
Published: May 2005

Vinyltitanium(IV) species prepared by the alkylation of titanium–vinylcarbene complexes with tert-butyl chloride reacted with aldehydes to give allylic alcohols. The reaction of vinyltitanium species with terminal alkynes produced conjugated dienes, in which a vinyl group regioselectively bonded to the unsubstituted side of carbon–carbon triple bond.
Phthalocyanines Obtained from Phthalonitriles with Phenyl Derivatives: A New Method for the Synthesis of the Phthalonitriles by Use of Suzuki-Coupling Reaction
Authors: Sugimori Tamotsu , Okamoto Satoru , Kotoh Naoko , Handa Makoto , Kasuga Kuninobu
Published: May 2005

Phthalocyanines peripherally introduced with four phenyl derivatives have been prepared from the corresponding phthalonitriles, which were obtained in high yields with Suzuki-Miyaura coupling. It was found that the substituent groups on the pc ring significantly affect the spectral properties and solubilities in chloroform.