bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidative Dimerization of Pyrrole Derivatives. III. Studies on the 3-Carbonyl Substituted Pyrryl Radicals.
Authors: Tomita Kuniyuki , Yoshida Norio 
Published: July 2006

Abstract
The thermochromic properties of the dimers in solution, obtained by oxidation of 3-carbonyl substituted pyrroles, was determined as being due to the reversible dissociation into pyrryl radicals. The structure and character of the pyrryl radicals are discussed on the basis of substituent effect on thermochromism and ESR studies.
Self-Diffusion of Chloride Ions in Manganese Bichloride Crystallites
Authors: Sensui Yoshihiro 
Published: July 2006

Abstract
The self-diffusion of chloride ions in the powdery crystals of manganese dichloride was studied in the temperature range of 200–420°C by the use of the isotopic-exchange method. The activation energies for self-diffusion were determined to be 0.95 and 1.6eV in a lower and a higher temperature region respectively. From these, the activation energy for the migration of chloride ions and the formation energy of an anion vacancy or a pair of an anion and a cation vacancy were deduced.
Synthetic Reactions by Complex Catalysts XXVIII. Reaction of β-Propiolactone with Alkyl Halide Caused by Cu2O-Isonitrile Complex
Authors: Saegusa Takeo , Murase Ichiki , Nakai Michio , Ito Yoshihiko 
Published: July 2006

Abstract
Oligomerization of β-propiolactone (BPL) caused by the Cu2O-isonitrile complex in the presence of alkyl halide was studied, and an oligomeric mixture of acrylate derivatives 3 (n=1, 2 and 3 in Eq. (3)) was isolated in fairly high yields. The complex catalyst showed a distinguished catalytic activity for the oligomerization of BPL. The reaction mechanism involving an intermediate of organocopper(I) isonitrile 4, which is converted into copper (I) acrylate isonitrile complex 5 was presented.
The Photo-decomposition of 1-Azidopyrene in the Benzene Solution
Authors: Yamaoka Tsuguo , Kashiwagi Hiroshi , Nagakura Saburo 
Published: July 2006

Abstract
1-Nitrenopyrene (Py-N) was produced by the photo-decomposition of 1-azidopyrene (Py-N3) in the benzene solution at 77°K and at room temperature. At 77°K, Py-N was found to be stable, and its electronic absorption and ESR spectra were measured. The result shows that its ground state is triplet and the fine structure constant, D, is equal to 0.73 cm−1. At room temperature, 1-nitrenopyrene was found to be converted easily into 1,1′-trans-azopyrene (trans-Py-N=N–Py) in the oxygen-free benzene solution and into 1-nitropyrene (Py-NO2) in addition to Py-N=N-Py in the oxygen-containing benzene solution. The decay process of Py-N as a reaction intermediate and the formation processes of the reaction products were studied by the flash-photolysis technique, and from an analysis of the results, the rate constants at 23°C were determined to be 2.1×109lmol−1 sec−1 and 1.4×103sec−1 for 2Py–N→trans-Py-N=N–Py and for Py–N+O2→Py-NO2, respectively.
Studies on Aminosugars. XXXI. Synthesis of 3,4-Dideoxy-3-enosides and the Corresponding 3,4-Dideoxysugars
Authors: Umezawa Sumio , Okazaki Yasushi , Tsuchiya Tsutomu 
Published: July 2006

Abstract
As model experiments to prepare unsaturated and deoxy variants of complex aminoglycosidic antibiotics, methyl 3,4-dideoxy-α-d-erythro-hexopyranoside (8) and methyl 2,6-diamino-2,3,4,6-tetradeoxy-α-d-erythro-hexopyranoside (15) have been synthesized through the corresponding 3,4-unsaturated glycosides (6, 12), which were prepared from the corresponding 3,4-di-O-mesyl derivatives (5, 11) by treatment with sodium iodide and zinc dust in high yields. These are rare examples of 3,4-dideoxy and 3,4-unsaturated sugars.
Crystal and Molecular Structure of ω-Amino Acids, ω-Amino Sulfonic Acids and Their Derivatives. II. The Crystal and Molecular Structure of α-Form of 3-Aminopropane Sulfonic Acid, Homotaurine
Authors: Ueoka Sumiko , Fujiwara Takaji , Tomita Ken-ichi 
Published: July 2006

Abstract
From ethanol aqueous solution, two forms of crystals of 3-aminopropane sulfonic acid (homotaurine) have been obtained in different crystal systems. The α-form is orthorhombic, space group Pmn21, with two molecules in a unit cell of the dimensions; a=7.059, b=5.492 and c=7.428 Å. The X-ray structure analysis was carried out by the application of usual heavy atom method and refined by three dimensional least-squares procedure. The final R-value is 0.059. In the crystalline state, homotaurine molecule has the zwitterionic structure, NH3+–CH2–CH2–CH2–SO3−, with trans-zigzag skeletal configuration, and non-hydrogen atoms except two oxygen atoms lie exactly on a mirror plane. Each molecule in the crystal is connected by three dimensional network of three NH···O hydrogen bonds.
Studies of Acenaphthene Derivatives. XXVI. The Thermal Cycloaddition of 2-Diazoacenaphthenone to Isocyanates
Authors: Tsuge Otohiko , Shinaki Ichiro , Koga Masahiro 
Published: July 2006

Abstract
Although 2-diazoacenaphthenone did not react with phenyl isocyanate or phenyl isothiocyanate on prolonged reflux in toluene, it reacted with strongly electrophilic benzoyl and p-chlorobenzoyl isocyanates and thiobenzoyl isocyanate to give the corresponding spiro[acenaphthenone-2,5′-oxazolin-4′-one] and the spiro-thiazolin-4′-one in good yields. On the other hand, the reaction of the α-diazoketone with benzoyl isothiocyanate gave 8-benzoylacenaphtho[1,2-d]isoxazolin-9-thione, which on catalytic hydrogenolysis over PtO2 gave the dihydro compound corresponding to reductive cleavage of N–O bond of the isoxazoline ring. Furthermore, the reaction of the α-diazoketone with benzenesulfonyl isocyanate gave two stereoisomeric bis-spiro-azetidinones. The mechanisms of these reactions are proposed.
The Exchange Reaction of Deuterium with the Hydroxyl Groups of Zeolite Catalysts
Authors: Imanaka Toshinobu , Okamoto Yasuaki , Takahata Kazunori , Teranishi Shiichiro 
Published: July 2006

Abstract
In order to estimate the reactivity of each hydroxyl group, the exchange reaction of deuterium with the hydroxyl groups on the surfaces of the HX, HY, and CaHX zeolites and aerosil was investigated kinetically by an infrared method. The hydroxyl groups appearing at 3660 cm−1 on the HX and HY zeolites were more readily exchanged with deuterium than were the other hydroxyl groups on the two zeolites. However, in the case of the CaHX, the order of activities of each hydroxyl group changed with the pressure of deuterium. The rate equation for the reaction is expressed by a Langmuir-type equation. This fact indicates the homogeneity of each hydroxyl group on zeolite. It was found that adsorbed water and carbon dioxide catalyzed the exchange reaction. Furthermore, a compensation effect between the apparent activation energies and the frequency factors occurs in this reaction.
Chemical Studies on Tuberactinomycin. IV. The Chemical Structure of γ-Hydroxy-β-lysine, A New Amino Acid Isolated from Tuberactinomycin A and N
Authors: Wakamiya Tateaki , Shiba Tetsuo , Kaneko Takeo 
Published: July 2006

Abstract
γ-Hydroxy-β-lysine is a new basic amino acid isolated from the hydrolyzates of antitubercular peptides, tuberactinomycin A and N as one of the composite amino acids. The chemical structure and stereochemistry of the amino acid were established on the basis of chemical reactions and physical measurements, i.e., IR, NMR, and ORD. One stereoisomer obtained in hydrochloric acid hydrolysis was determined as threo-γ-hydroxy-l-β-lysine (Ia), while the other one obtained in concentrated sulfuric acid hydrolysis as an erythro isomer (Ib).
Reduction of 7-Methylenebicyclo[3.3.1]nonan-3-one and Related Compounds: Structural Investigation of the Products
Authors: Kimoto Koichi , Imagawa Takeshi , Kawanisi Mituyosi 
Published: July 2006

Abstract
Hydrogenation of 7-methylenebicyclo[3.3.1]nonan-3-one (1) over platinum oxide in acetic acid yielded 7α-methylbicyclo[3.3.1]nonan-3α-ol (2) as the sole product. Hydrogenation of (1) in ethyl acetate afforded 7α-methylbicyclo[3.3.1]nonan-3-one (3) as a reduced product and 7-methylbicyclo[3.3.1]non-6-en-3-one (4) as an isomerized product. Hydrogenation of 1 over palladium on carbon gave no reduced product but 4 in 100% conversion. Hydrogenation of 7-methylenebicyclo[3.3.1]nonan-3α-ol (7) and -3β-ol (8) over platinum oxide in acetic acid gave 2 and 7α-methylbicyclo[3.3.1]nonan-3β-ol (5), respectively. From studies based on NMR spectroscopy with use of a shift-reagent, it is concluded that the major conformer of 2 and 5 is of chair-boat form. By the equilibration experiment between 2 and 5 using aluminum isopropoxide in isopropyl alcohol at 110°C, the ΔG° value was found to be −2.2 kcal/mol.
Studies on Oxosulfonium Salts. I. Preparation and Physical Properties.
Authors: Kobayashi Michio , Kamiyama Kenji , Minato Hiroshi , Oishi Yukio , Takada Yoko , Hattori Yoshitaka 
Published: July 2006

Abstract
Methods for preparation and physical properties of oxosulfonium salts have been discussed. Optically active ethylmethylphenyloxosulfonium salts have been prepared and their absolute configurations have been determined.
Some Physico-chemical Properties of Vanadium Oxide Supported on Silica or γ-Alumina
Authors: Yoshida Satohiro , Iguchi Toshikatsu , Ishida Shingo , Tarama Kimio 
Published: July 2006

Abstract
The interactions between vanadium(V) oxide and carriers were investigated in the vanadium oxide catalysts supported on silica and γ-alumina by measuring X-ray diffraction patterns, ESR spectra, solubilities into 0.3 n ammoniacal solutions and reduction rates by benzene. A part of vanadium oxide on the carriers was insoluble in an ammoniacal solution, while unsupported vanadium oxide was easily soluble, and the reduction rates of the catalysts were remarkably affected by the carriers and the vanadium oxide contents. ESR spectra revealed that the vanadium oxide was stabilized by interaction with carriers as a square pyramidal one (VO5) and a tetrahedral one (VO4) on the surfaces of γ-alumina and silica, respectively. Massive vanadium(V) oxide crystals grew on these interacted layers with the increase of the oxide contents.
The Chemical Behavior of 64Cu Recoil Atoms in the Mixed System of Copper Phthalocyanine and Metal-free Phthalocyanine
Authors: Kudo Hiroshi 
Published: July 2006

Abstract
In order to elucidate the effect of the crystal structure on the chemical behavior of 64Cu recoil atoms in copper phthalocyanine, the author studied the mixed system of copper and metal-free phthalocyanine. It was found that the initial retention increased both in the mixed crystal and in the mixed-disk target. The addition of metalfree phthalocyanine sensitized the target to the thermal annealing reaction, and the rate of the reaction in the mixed crystal was faster than that in the unmixed crystal. The electron acceptor in the target was also found to increase the initial retention. The results were discussed in terms of the electrical properties of the target, which were changed by the change in the spatial arrangement of the molecules.
Kinetics and Mechanisms of the Reaction of Tl(III) with Variamine Blue, [N-(p-Methoxyphenyl)phenylenediamine] in Aqueous Perchlorate Media
Authors: Imamura Taira , Fujimoto Masatoshi 
Published: July 2006

Abstract
A stopped-flow apparatus was used to study the kinetics of the redox reaction of Tl(III) with Variamine Blue under nitrogen atmosphere in acid (0.2–0.6 m) perchlorate media of ionic strength μ=1.0 m. The observed second-order rate constant increases inversely with hydrogen ion concentration. The proposed mechanism involves the overall rate-determining steps
Tl3++(V.B.)\oversetk1\ightleftharpoonsTl++(V.B.)ox+2H+
TlOH2++(V.B.)\oversetk2\ightleftharpoonsTl++(V.B.)ox+H2O+H+
where (V.B.) and (V.B.)ox are a reduced form and an oxidized form of Variamine Blue respectively. The rate constants are evaluated to be k1≤102 m−1 sec−1, and k2=3.6×104 m−1 sec−1 at 25°C. The activation energy E2 for k2 is 11±0.8 kcal·mol−1.
The Reaction of Tris(acetylacetonato)cobalt(III) with Bromine in Dichloromethane
Authors: Nakamura Yukio , Gotani Mitsuru , Kawaguchi Shinichi 
Published: July 2006

Abstract
Dibromo(acetylacetone)cobalt(II), a new complex containing an acetylacetone molecule as the bidentate ligand, was formed by the reaction of tris(acetylacetonato)cobalt(III) with bromine in dichloromethane, and characterized by elemental and thermogravimetric analyses and electronic and infrared spectra. The same compound was also prepared by direct addition of acetylacetone to anhydrous cobalt(II) bromide. The radical nature of the redox step involved in the reaction pathway from the starting cobalt(III) chelate to the product cobalt(II) complex of acetylacetone was demonstrated by polymerization of methyl methacrylate and styrene remarkably enhanced by the reaction system.
Acidic Property and Catalytic Activity of TiO2·ZnO
Authors: Tanabe Kozo , Ishiya Chijiko , Matsuzaki Isao , Ichikawa Ichiro , Hattori Hideshi 
Published: July 2006

Abstract
A new type of mixed metal oxide TiO2·ZnO was prepared by either heterogeneous or homogeneous co-precipitation and the acidic property was measured by n-butylamine titration and by observation of infrared spectra of adsorbed pyridine. It was found that TiO2·ZnO containing about 7 or 57% of ZnO shows a very large acid amount of 0.5–0.9 mmol/g and a fairly high acid strength of H0≤−3, the acid sites being both Brönsted and Lewis type and the acid sites of high strength created by heterogeneous precipitation. The catalytic activity and selectivity of TiO2·ZnO were found very high for the hydration reaction of ethylene. The catalyst was active also for the alkylation of phenol by methanol and gave only monoalkylated products.
The Reaction of Bis(acetylacetonato)cobalt(II) with Bromine in Dichloromethane
Authors: Nakamura Yukio , Kanehisa Nobuko , Kawaguchi Shinichi 
Published: July 2006

Abstract
When bis (acetylacetonato)cobalt(II) is allowed to react with twice molar quantity of bromine in dichloromethane, cobalt(II) bromide and γ-bromoacetylacetone are produced ultimately. From a deep blue solution of an equimolar reaction mixture at 0°C an intermediary product was isolated and characterized to be dimeric bromo(acetylacetonato)cobalt(II) by means of elemental analysis and molecular weight determination. The structure of this compound was inferred to be tetrahedral from absorption spectra and magnetic data. Acetylacetonate groups were supposed to act as bridging ligands on the basis of IR data in the lower frequency region. Dibromobis(acetylacetonato)dicobalt(II) was also derived from dibromo(acetylacetone)cobalt(II) by the reaction with sodium acetylacetonate in acetylacetone at 0°C.
Reactions of Dibromoalkanes with Dimethyltin Bis(N,N-dimethylthioseleno and diselenocarbamates) and Related Compounds
Authors: Tanaka Koji , Tanaka Toshio 
Published: July 2006

Abstract
Dimethyltin-bis(N,N-dimethylthioselenocarbamate), (CH3)2Sn[SSeCN(CH3)2]2, dimethyltin-bis(N,N-dimethyldiselenocarbamate), (CH3)2Sn[Se2CN(CH3)2]2, and dimethyltin-bis(N-methyl-N-phenyldiselenocarbamate), (CH3)2Sn[Se2CN(CH3)(C6H5)]2, react with dibromoalkanes to give bis(1-thia-3-selenacycloalkyl-2-dimethylimminium)dimethyltin tetrabromide, (Remark: Graphics omitted.) (m=2, 3), 1,3-diselenacycloalkyl-2-dimethylimminium dimethyltin bromides, (Remark: Graphics omitted.) (n=1, m=2 and n=2, m=3), and 1,3-diselenacyclopentyl-2-methylphenylimminium bromide, (Remark: Graphics omitted.), respectively. The infrared and PMR spectra indicate that the positive charges of 1-thia-3-selena- and 1,3-diselenacycloalkylimminium ions are more delocalized in the higher homologs than in the lower ones.
Kinetics of the γ-Ray Induced Polymerization of Ethylene in 1,2-Dichlorotetrafluoroethane
Authors: Suganuma Fujio , Hagiwara Miyuki , Mitsui Hiroshi , Kagiya Tsutomu 
Published: July 2006

Abstract
The γ-ray induced polymerization of ethylene in bulk or in solution in the presence of 26.9–67.3 g of 1,2-dichlorotetrafluoroethane (R-114) was carried out in a 100-ml reactor under a pressure of 210–400 kg/cm2 and at 30°C, with a dose rate of 1×104–9×104 rad/hr. The rate of the polymerization and the molecular weight of the polymer formed increased with the reaction time and the pressure. The rate also increased upon the addition of an appropriate amount of R-114. On the other hand, the molecular weight decreased with an increase in the amount of R-114. The dose-rate exponents of the rate and the molecular weight were found to be 0.8 and −0.2 respectively. These results were analyzed kinetically, and the rates and the rate constants of the initiation, propagation, transfer, and termination reactions were evaluated. Further, the roles of R-114 in the polymerization were discussed.
Syntheses of All Isomers of Naphthalenetricarboxylic Acids
Authors: Dozen Yasuhiko 
Published: July 2006

Abstract
All the fourteen isomers of naphthalenetricarboxylic acids have been synthesized by the oxidation of trimethylnaphthalenes, dimethylacetonaphthones, dimethylnaphthoic acids, methylnaphthalenedicarboxylic acids, β-(dimethylnaphthoyl)propionic acid, or β-(acenaphthoyl)propionic acids with aqueous sodium bichromate or potassium ferricyanide. Most of these naphthalenetricarboxylic acids, acid anhydrides, and trimethyl esters are new compounds.
The Constituents of Arthraxon hispidus Makino, Miscanthus tinctorius Hackel, Miscanthus sinensis Anderss, and Phragmites communis Trinius
Authors: Kaneta Makoto , Sugiyama Noboru 
Published: July 2006

Abstract
From the leaves and stems of Arthraxon hispidus Makino, aconitic acid, luteolin, luteolin-7-glucoside, and a new flavone, arthraxin, have been isolated. Luteolin, luteolin-7-glucoside, and arthraxin were also isolated from Miscanthus tinctorius Hackel, and tricin was isolated from Miscanthus sinensis Anderss and Phragmites communis Trinius.
The Reactions of Metal Acetylacetonates and Related Compounds with 2,2-Diphenyl-1-picrylhydrazyl
Authors: Uehara Kaku , Kamei Kiyohiro , Tanaka Makoto , Murata Niro 
Published: July 2006

Abstract
Some metal acetylacetonates (M(acac)n) were observed to react with the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in organic solvents. For the reaction of cupric 3-α-butenylacetylacetonate with DPPH in benzene and cyclohexane, the following rate equation was obtained: R=k[cupric chelate][DPPH]. The activation parameters of the reaction were remarkably dependent upon the nature of the substituent and the metal atom in M(acac)n, and upon the solvent. The results of the kinetic studies and the analytical work suggested that M(acac)n reacted with DPPH to yield 2,2-diphenyl-1-picrylhydrazine (DPPH-H) via the reduction of the central metal of the M(acac)n.
Stereochemical Studies of Monoterpene Compounds. XIV. The Rotational Conformation of the Acetyl and the Formyl Groups of Monoterpene α,β-Unsaturated Carbonyl Compounds
Authors: Suga Takayuki , Imamura Kiyoshi , Shishibori Tsuyoshi 
Published: July 2006

Abstract
Temperature-dependent circular dichroism measurements in the n−π* transition enabled us to predict the preferred rotational conformation of the acetyl and the formyl groups of such monoterpene α,β-unsaturated carbonyl compounds as (+)-1-acetyl-4-methylcyclohexene (1), (−)-perillaldehyde (2), (+)-1-acetyl-2,4-dimethyl-cyclohexene (3), and(−)-myrtenal (4).
Stereochemical Studies of Monoterpene Compounds. XV. A Conformational Study of Carvomenthone Derivatives by Means of Temperature-dependent Circular Dichroism
Authors: Suga Takayuki , Watanabe Satoru 
Published: July 2006

Abstract
The conformations of (1R:4R)-(−)-p-menth-8-en-2-one (1) and of diastereoisomeric pairs of (+)-1-hydroxy-p-menth-8-en-2-one, (2) and (3), (+)-1-hydroxy-p-menthan-2-one, (6) and (7), and (+)-1-hydroxy-8-bromo-p-menthan-2-one, (10) and (11), were examined by a combination of infrared spectra and temperature-dependent circular-dichroism (CD). Explanations are given mainly with regard to the epimeric pair, (2) and (3). It is demonstrated that α-hydroxyketone (2) exists in a conformational equilibrium among 2a, 2b, and 2c. The 2a conformer predominantly exists in a polar medium and at low temperatures, whereas the 2b conformer is more stable than 2a in a nonpolar medium. On the other hand, the epimer (3) exists preferentially in the 3a conformation in both polar and nonpolar media and at low temperatures. The CD curves of compounds 6 and 7 exhibited the exactly same behavior as those in compounds (2) and (3) respectively. These results are interpreted in terms of the competition of the steric factor and the intramolecular hydrogen bonding.
A New Steroid with an Unnatural Configuration: 8α,14β-Progesterone
Authors: Mukawa Fumikazu , Nagata Wataru 
Published: July 2006

Abstract
A modified Wolf-Kishner reduction of certain 5α,8α,14β-11-oxo steroids gave the corresponding 11-deoxy steroids with the same stereochemistry, and the introduction of a double bond at C4–C5 leads to 8α,14β-progesterone. The structure and configuration of this compound are discussed on the basis of its physical properties. Its unnatural backbone stereochemistry was established by transformations from the 8α,14β-1,4-diene derivative to the known 8α,14β-estrone.
Studies on Geometrical Isomerism by Nulear Magnetic Resonance. V. Stereochemistry of 5-Substituted 4-Alkoxycarbonyl-2-carbamoylimino-1,3-oxathiolanes
Authors: Hayashi Toshio , Akano Makiko , Yokono Tetsuro , Uzawa Jun , Kambe Satoshi , Midorikawa Hiroshi 
Published: July 2006

Abstract
An equimolar reaction of thiocyanoacetic esters with aldehydes in the presence of potassium fluoride or carbonate leads to a stereoisomeric mixture of cis and trans isomers of 5-substituted 4-alkoxycarbonyl-2-carbamoylimino1,3-oxathiolanes. Several of them were separated into two isomeric forms, whose geometrical configurations were determined by means of nuclear magnetic resonance technique. The vicinal coupling constant between the 4-and 5-protons is consistently larger for the cis forms than for the trans. In the case of the 5-aryl derivatives, the signals of the alkoxycarbonyl group appear at higher field for the cis isomers than for the trans. The composition ratios of cis and trans isomers of the oxathiolanes prepared are determined. Infrared data of the cis and trans oxathiolanes are also reported.
Reactions of 5N-(1,2,3-Triazol-1-yl)tropolones
Authors: Horino Hiroshi , Toda Takashi 
Published: July 2006

Abstract
The chemical properties of 5N-(l,2,3-triazol-1-yl)tropolones are investigated. The reactions of 5N-(4′-ethoxycarbonyl-5′-methyl-1,2,3-triazol-1-yl)tropolone methyl ether (I) with malononitrile and ethyl cyanoacetate gave the corresponding azulene derivatives, but with ethyl acetoacetate the reaction afforded a 1-oxaazulan-2-one derivative. The methoxyl group of I is replaced by aliphatic amines to form 2-aminotropone derivatives. Also, the reaction of I with guanidine and o-phenylenediamine gave a 1,3-diazaazulene derivative and a quinoxaline derivative respectively. The brominations of triazolyltropolones afforded the corresponding 3,7-dibromotropolone derivatives, while reactions with thionyl chloride gave 2-chlorotropone derivatives.