bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactivities of Stable Rotamers. XXXIII. Addition of Positive Bromine Compounds to the Olefinic Moiety of 1-(9-Fluorenyl)-2-(1-methylethenyl)naphthalene Rotamers and Facile Benzene Ring Cleavage in One of the Intermediates from the sp-Form
Authors: Oki Michinori , Maeda Kiyoka , Akinaga Tadashi , Kataoka Yasukazu , Toyota Shinji 
Published: August 2006

Abstract
Addition of positive bromine compounds to the title olefins was carried out with use of N-bromosuccinimide–water and t-butyl hypobromite and the results are compared with the case of bromine addition. In the case of the ap-isomer, the reactions reported here all produce bromo-olefins in addition to an addition product, in contrast to the case of bromine which gives only an addition product. The sp-isomer afforded the same products as was observed for the bromine-addition but with different proportions of the products. The anionic species of more proton affinity and consequently of less affinity toward carbocations caused a decrease in formation of the addition product and an increase in formation of bromo-olefins in the case of the ap-isomer. The ratios of products, bromo-olefins to a cyclized compound, were affected by the anionic species in the case of sp-isomer: Both N-bromosuccinimide–water and t-butyl hypobromite yielded about the same amounts of the two olefins, but the yields of the cyclized compound varied significantly. The results are not explained in a straightforward manner. Probably solvent effects are important. In addition, the reaction of the sp-form with N-bromosuccinimide in tetrahydrofuran-water afforded (7R*,7aS*,12bS*)-7-bromomethyl-8-[(E)-bromomethylene]-7-methyl-7a-[(Z)-3-oxo-1-propenyl]-7,7a,8,12b-tetrahydrobenzo[5,6]pentaleno[1,2-a]naphthalene, a compound which is derived by cleavage of a benzene ring. The structural features of the last compound are also discussed.
Gas Phase Oxidation of Benzene to Phenol under the Simultaneous Feeding of Hydrogen and Oxygen. III. Catalyst Prepared from Cu(II) Phosphate
Authors: Kitano Tomoyuki , Nakai Toshihiro , Nitta Masahiro , Mori Miki , Ito Sotaro , Sasaki Kazuo 
Published: August 2006

Abstract
The performance of silica supported Pd–Cu composite catalyst developed previously for direct oxidation of benzene to phenol has been improved by changing the copper ion source from Cu(II) sulfate to Cu(II) phosphate and by additional impregnation of phosphoric acid. The reaction proceeds under the simultaneous feeding of benzene, hydrogen and oxygen at 200 °C with a rate of phenol production ca. 0.4 mmol h−1 (g-cat)−1, which is ten times greater than that we have reported previously with a catalyst prepared from Cu(II) sulfate. With this catalyst, complete oxidation to carbon dioxide is also retarded to increase the selectivity of phenol. The improvement of catalytic activity arises apparently from the diminution of the yield of water and is ascribed to the presence of a thin liquid film over the silica surface.
A Novel Synthesis of Alkyl Chloroformate in the Gas Phase by Palladium-Catalyzed Reaction Using XCl (X = H or NO), CO, and Alkyl Nitrite
Authors: Manada Noriaki , Murakami Masato 
Published: August 2006

Abstract
A novel synthesis of chloroformate was developed by palladium-catalyzed reaction of XCl (X = H or NO), CO, and alkyl nitrite in the gas phase. When PdCl2/γ-Al2O3 or PdCl2/SiO2 was used as a catalyst, chloroformate was produced in good yield and with high selectivity. The reaction temperature had a strong influence on the formation rate of chloroformate, and its selectivity drastically depended on the nitrite/chloride ratio. When the nitrite/chloride ratio was less than 2, the selectivity of chloroformate was almost 100%. Dependence of the formation rate on the concentrations of CO and methyl nitrite was also examined.
A Conductometric Glucose Sensor Based on a Twin-Microband Electrode Coated with a Polyaniline Thin Film
Authors: Miwa Yukiharu , Nishizawa Matsuhiko , Matsue Tomokazu , Uchida Isamu 
Published: August 2006

Abstract
A conductometric glucose sensor was fabricated by coating a twin-microband electrode with a bilayer of a membrane composed of polyaniline and glucose oxidase/gluconolactonase films. The enzyme-catalyzed hydrolysis of glucose induces a change in the conductivity of the pH-sensitive polyaniline film. The conductivity change was detected by the current flowing between the two-band electrode. The sensor demonstrates clear responses to glucose up to 1 mM.
Palladium-Catalyzed Double-Bond Migration in the Homoisoflavone System
Authors: Hoshino Yukio , Takeno Noboru 
Published: August 2006

Abstract
3-Benzylidene-4-chromanones were converted to 3-benzylchromones in HMPA at 200 °C in excellent yields. The reaction was irreversible and efficiently promoted by palladium catalysts in a remarkably shortened reaction time (3 h), compared with the existing procedure (24 h).
Positional Assignments of a Substituent Group of 3-Substituted Juglones by the Off-Resonance 13C NMR Spectra
Authors: Tanoue Yasuhiro , Terada Akira , Sakata Kazunori , Hashimoto Mamoru , Morishita Shin-ichi , Hamada Moritsugu , Kai Norihisa , Nagai Takeshi 
Published: August 2006

Abstract
Taking into account the fact that the long-range 13C–1H coupling constant 3JCH is greater than 2JCH, positional assignments of a substituent group of 3-substituted juglones were easily accomplished by off-resonance 13C NMR spectra using a 60-MHz instrument for 1H. This method was applicable to a structural determination of naphthazarin derivatives.
Facile Preparation of a Phenyl 1-Thioglycoside of Allopyranosylallopyranose from Allyl N,N′-Diacetylchitobioside
Authors: Takahashi Shunya , Terayama Hiroyuki , Sakairi Nobuo , Kuzuhara Hiroyoshi 
Published: August 2006

Abstract
An allopyranosyl analog of allyl N,N′-diacetylchitobioside was converted to the corresponding N,N′-diphthaloylated glycosyl acetate in good yield. A thioglycosidation reaction of the glycosyl acetate gave phenyl 3,6-di-O-acetyl-4-O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-d-allopyranosyl)-2-deoxy-2-phthalimido-1-thio-β-d-allopyranoside, the key intermediate employed in the total synthesis of an insect chitinase inhibitor, allosamidin.
Synthesis of 9-Oxa-5-azatricyclo[4.3.0.03,7]nonan-4-ones from 4,4,5-Trihydroxy-2-oxabicyclo[3.2.0]heptane-exo-6-carbonitriles by Their Ring Transformation
Authors: Shimo Tetsuro , Ohshima Kazuhiro , Somekawa Kenichi , Kawaminami Masaru 
Published: August 2006

Abstract
The hydrolysis of [2+2]cycloadducts 4 or their hydrates 5, which were obtained from the regioselective photoreactions of 4-hydroxy-2,5-dimethyl-3(2H)-furanone (1) with cyanoethylenes, afforded the tittle γ-lactams 7 via an interesting ring transformation.
Spectroscopic Properties of Several Molecular Species of [N,N′-(o-Phenylene)bis(salicylideneaminato)]cobalt(II) in N,N-Dimethylformamide and CH2Cl2 Solutions
Authors: Ohashi Yukako , Nakamura Mikio 
Published: August 2006

Abstract
Based on the temperature and concentration dependencies of the UV-vis and 1H NMR spectra of [N,N′-(o-phenylene)bis(salicylideneaminato)] cobalt(II) ([Co(saloph)]), the existence of several species ([Co(saloph)], [Co(saloph)(dmf)], [Co(saloph)(dmf)2], and a dimer [Co(saloph)(dmf)]2) is discussed in N,N-dimethylformamide (dmf) and CH2Cl2. The values of ΔH° and ΔS° were determined to be −3.7 kJ mol−1 and −17 J K mol−1, −30 kJ mol−1 and −145 J K mol−1, and −39 kJ mol−1 and −110 J K−1 mol−1 for the formation of [Co(saloph)(dmf)], [Co(saloph)(dmf)2] and [Co(saloph)(dmf)]2, respectively. Transient absorptions with lifetimes of 10−3 s and 4 × 10−6 s were observed in dmf solution by 337 nm irradiation.
Study of the Pyridine 1-Oxide-Catalyzed Two-Phase Reversible Exchange Reaction of Benzoyl Chloride and Butanoate Ion
Authors: Wang Maw-Ling , Ou Chin-Chou , Jwo Jing-Jer 
Published: August 2006

Abstract
The reaction of benzoyl chloride (PhCOCl) and butanoate ion (PrCOO−) catalyzed by pyridine 1-oxide (PNO) in the medium H2O/CH2Cl2 leads to equilibrium with butanoyl chloride (PrCOCl) and benzoate ion (PhCOO−) and vice versa. The rate-determining step takes place in the organic phase and PrCOCl is much more reactive than PhCOCl. The effects of chloride ion, hydroxide ion, pyridine 1-oxide, reactants and temperature on the reaction rate and the equilibrium conversion of acyl chloride (RCOCl) were investigated. Satisfactory detailed mechanistic interpretations of the kinetic results are given.
Application of a Steady-State Flow Analysis to a Long-Period Reaction in a Continuous-Flow System
Authors: Zhang Chong-Liang , Narusawa Yoshio 
Published: August 2006

Abstract
A steady-state flow analysis (SSFA) has been developed and applied to the determination of trace amounts of manganese in an unsegmented flow system. Because this method is no longer characterized by the sample zone dispersion and/or the sequentiality, sharp decreases in the analytical speed and sensitivity for long-period reactions can be avoided. This method has been demonstrated to be useful, especially for long-period reactions in continuous-flow systems. Optimizations of a steady-state flow manifold are described in detail, and determinations of sub-nanogram manganese have been carried out in a long-period reaction of manganese-catalyzed malachite green with periodate. As a result, several improvements were made in comparison with an ordinary flow-injection method: The detection limit decreased to ca. one-thirtieth, the analytical speed was ca. 2.5 times, the coil length was one-twelfth, the dispersion coefficient was ca. one-eighteenth, while the reaction time was ca. 2.3 times. Determinations of manganese in reference materials of NIES of Japan were performed, and the results were obtained as follows: Manganese in μg g−1 in sargasso, tea leaves, and rice flour (containing high cadmium content) were 22.0 ± 2.6, 686 ± 19, and 35.7 ± 1.7, respectively. These results correspond well with their reference values.
Optical Resolution, Characterization, and X-Ray Crystal Structures of Diastereomeric Salts of Chiral Amino Acids with (S)-(−)-1-Phenylethanesulfonic Acid
Authors: Yoshioka Ryuzo , Ohtsuki Osamu , Da-te Tadamasa , Okamura Kimio , Senuma Masaru 
Published: August 2006

Abstract
Ten Dl-Amino acids (AA), including neutral, and basic amino acids, and an imino acid, were optically resolved, without derivatization into their covalent compounds, by means of fractional crystallization of their diastereomeric salts with (−)-1-phenylethanesulfonic acid (PES) in various solvents. Several pairs of the diastereomeric crystalline salts formed during the resolutions were analyzed by DSC and spectroscopy, which showed that the successful resolutions were attributable to differences in various physicochemical properties between the more-soluble d-AA·(−)-PES and less-soluble l-AA·(−)-PES. Chiral recognition of the most successfully resolved species, Dl-p-hydroxyphenylglycine (HPG) salt, was explored by comparing the X-ray crystal structures of d- and l-HPG·(−)-PES. The two crystal structures differed obviously in their hydrogen-bonding networks: the less-soluble l-HPG·(−)-PES only had strong hydrogen-bonded infinite chains of HPG in a “head-to-tail” arrangement through the p-hydroxyl group, the structure of which was more geometrically stable than that of the more-soluble d-HPG·(−)-PES. The differences in the two crystal structures related to striking differences in their solubilities and thermal properties.
The Ene and the Diels–Alder Reactions of CF3CHO with Dienes Using ZnX2 (X: Cl, OTf)
Authors: Hayashi Eiji , Takahashi Yukio , Itoh Hironori , Yoneda Norihiko 
Published: August 2006

Abstract
The reaction of CF3CHO with dienes using ZnX2 (X: Cl, OTf) in organic solvents (CH2Cl2 or CH3NO2) gave fairly good results in depressing unfavorable reactions and affording the preferential formation of the ene reaction products, 1-trifluoromethyl-3-buten-1-ols, together with the Diels–Alder reaction products. Particularly, Zn(OTf)2, which is insoluble in CH2Cl2, had some predominance for the formation of ene-type products in preference to ZnCl2, and could be recycled without any deterioration in its catalytic activity.
Production and Immunochemical Feature for Syngeneic Monoclonal Anti-Idiotypic Antibodies to Morphine
Authors: Usagawa Takashi , Hifumi Emi , Uda Taizo 
Published: August 2006

Abstract
Three syngeneic monoclonal anti-idiotypic antibodies for morphine were produced by using a murine morphine-specific monoclonal antibody (MO-3) as an idiotype. The resulting anti-idiotypic antibodies and morphine were competitively reacted with MO-3 in a dose-dependent manner. The reactivity of one molecule of the anti-idiotypic antibody was found to correspond with two molecules of morphine based on a competitive idiotype–anti-idiotype immunoassay.
Hydrolysis of Acetonitrile, Catalyzed by Octaacetatotetraplatinum(II). — High Reactivity of Coordination Sites Trans to the Pt–Pt Bond —
Authors: Yamaguchi Tadashi , Adachi Hisako , Ito Tasuku , Sasaki Yoichi 
Published: August 2006

Abstract
The platinum(II) cluster, [Pt4(CH3COO)8], catalyzes the hydrolysis of acetonitrile to acetamide in acetonitrile–water mixtures. Typical turnover number was 104 mol h−1 at 80 °C. The catalyst was slowly deactivated by the accumulation of the less active acetamide-substituted species, as well as by its decomposition.
Chain Compound of Molybdenum(II) Pivalate Bridged by 4,4′-Bipyridine
Authors: Handa Makoto , Mikuriya Masahiro , Nukada Ryoji , Matsumoto Hiroki , Kasuga Kuninobu 
Published: August 2006

Abstract
A chain complex, [Mo2{O2CC(CH3)3}4 bpy]n (bpy = 4,4′-bipyridine), was prepared by the reaction of molybdenum(II) pivalate (Mo2{O2CC(CH3)3}4) and bpy. An X-ray crystal analysis showed that the chain structure is formed by alternating Mo2{O2CC(CH3)3}4 and bpy.
Novel Synthesis of Highly Functionalized Unsymmetrical Biphenyls
Authors: Kuroda Tooru , Yoshida Shin-ichi , Ogiku Tsuyoshi , Kondo Kazuhiko , Ohmizu Hiroshi , Iwasaki Tameo 
Published: August 2006

Abstract
Unsymmetrical biphenyls bearing methoxycarbonyl, formyl, and hydroxyl groups have been synthesized via aromatization of the aryltetrahydrobenzofuranone, followed by oxidative cleavage of the furan ring.
Syntheses and Electronic Properties of 6-Methylene- and 6-Iminocyclohepta[a]phenalen-12(6H)-one Derivatives
Authors: Kuroda Shigeyasu , Oda Mitsunori , Hirooka Syuzi , Takeda Hideya , Murotani Masahiro , Takahashi Yoshiyuki , Izawa Mayumi , Hirano Yukimoto , Kajioka Takanori , Yamada Masaki , Shimao Ichiro 
Published: August 2006

Abstract
Some new polyfused nonbenzenoid quinone derivatives, 6-(disubstituted methylene)- and 6-iminocyclohepta[a]phenalen-12(6H)-ones, were synthesized. The effects of substituents on electronic states were studied.
Surface Effects in the Born Solvation Model
Authors: Kumar Anil 
Published: August 2006

Abstract
The Born model is frequently used for calculating the work of solvation or free energy of ion–solvent interactions. The original Born equation does not reproduce the experimental data on solvation free energy, possibly due to the fact that the model does not take in account the changes in the structure of solvent in presence of an ion. The model also fails to account certain other experimental observations. A new derivation of the model is presented assuming the changes in the structure of solvent being analogous to surface phenomena. In addition to the successful checking its validity against experimental data, the revised expression can also yield the generalized Dupre rule for surface effects. Significance of new terms and their impact in accounting observed trends are discussed.
Preparation and Characterization of Cadmium(II) Halide Complexes with N-Substituted Glycines, and the Crystal Structures of Dichloro(N-methylglycine)cadmium(II) and Diaquadichloro(N,N-dimethylglycine)cadmium(II)
Authors: Yamada Junichi , Hashimoto Haruki , Inomata Yoshie , Takeuchi Toshio 
Published: August 2006

Abstract
Eight cadmium(II) halide complexes with N-methylglycine (sarcosine, Hsar), N,N-dimethylglycine (Hdmgly), and N,N,N-trimethylglycine (betaine, Hbet) have been prepared and characterized by using their infrared absorption spectra and thermal analyses. In addition, the crystal and molecular structures of [CdCl2(Hsar)] (1) and [CdCl2(Hdmgly)(H2O)2] (2) were determined by a single-crystal X-ray diffraction method. The crystal data for these two complexes are as follows: Complex (1): monoclinic, space group P21/n, a = 7.960(2), b = 13.844(1), c = 6.917(1) Å, β = 92.42(2)°, Z = 4. Complex (2): monoclinic, space group P21/a, a = 7.696(2), b = 21.854(4), c = 6.253(2) Å, β = 103.69(2)°, Z = 4. These structures were solved by the heavy-atom method and refined by full-matrix least-square methods to final R values of 0.043 for 2533 reflections about 1 and 0.068 for 3615 reflections about 2, respectively. For 1 the structure consists of a one-dimensional polymer bridged by two chlorine atoms. The cadmium atom is hexa-coordinated, being ligated with two oxygen atoms of a carboxyl group and four chlorine atoms. For 2 the cadmium atom is in a distorted octahedral geometry, ligated by a carboxylato oxygen atom, two water molecules, and three chlorine atoms, in which one is terminal and the other two are bridging cadmium atoms to make a polymer.
Adsorption Equilibria of Copper(II) Ion on Octadecyl-Bonded Silica Gel in the Presence of β-Diketones
Authors: Kato Masanao , Nakano Terunori , Hattori Toshiaki 
Published: August 2006

Abstract
Adsorptions of twelve β-diketones and their copper(II) complexes onto an octadecyl-bonded silica gel from an aqueous solution were measured by a batch technique. Several equilibrium constants for the adsorption reaction were measured and compared with those for solvent extraction. Using these constants, the abundance of each chemical species containing copper(II) ion in the presence of 2,4-pentanedione was calculated with respect to both the aqueous and the ODS gel phase.
Voltammetric Studies of the Redox Polymer Poly[4,4′-bipyridinium-1,1′-diylcarbonyl-2,5-thiophenediyl Dichloride] in Dimethyl Sulfoxide
Authors: Prasad Bhim Bali , Singh Sandhya 
Published: August 2006

Abstract
The electrochemical behavior of a redox polyelectrolyte, poly[4,4′-bipyridinium-1,1′-diylcarbonyl-2,5-thiophenediyl dichloride] at mercury electrode has been examined in dimethyl sulfoxide containing different concentrations of tetrabutylammonium iodide. The techniques of sampled DC polarography, pulse polarography (normal and differential), and cyclic voltammetry have been used. All polarograms revealed three one-electron reduction waves which are found either quasi-reversible or irreversible and usually adsorption-controlled by cyclic voltammetric experiments. The results were discussed by taking into account the implications of different concentrations of supporting electrolytes and polycation conformations on the adsorption processes consisting of preceding and following chemical reactions coupled with charge transfer reactions occurring at the electrode.
X-Ray Structural Characterization of the Protonation Sites in the Dihydrogenhexaniobate Anion
Authors: Ozeki Tomoji , Yamase Toshihiro , Naruke Haruo , Sasaki Yoshinori 
Published: August 2006

Abstract
Direct evidence for the locations of the hydrogen atoms in the dihydrogenhexaniobate anion has been obtained by a single-crystal X-ray diffraction method. Hexasodium dihydrogenhexaniobate icosahydrate (1), Na6[H2Nb6O19]·20H2O, crystallizes in triclinic form, space group , a = 10.364(2), b = 12.205(2), c = 9.026(2) Å, α = 103.21(2), β = 111.10(2), γ = 109.27(2)°, V = 924.0(5) Å3, Z = 1. The hexaniobate anion in 1 is protonated at two bridging oxygen atoms with the O–H distance of 0.69(6) Å. Due to the protonation and interactions with the Na+ counter-cations, the point symmetry of the hexaniobate anion is reduced to C2h from its possible highest symmetry of Oh.
Light and Shade Effect on the Synergistic Extraction of Iron(II) with 4,4,4-Trifluoro-1-(2-thienyl)-1,3-butanedione and Pyridine Base
Authors: Kawamoto Hiroshi , Itabashi Hideyuki , Urano Kiyomi 
Published: August 2006

Abstract
A synergistic extraction of iron(II) with 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione (TTA) and pyridine base was studied in order to clarify the effect of light and shade on the extraction. The extraction constant obtained at a shady place was larger than that obtained at a light place when pyridine or 4-methylpyridine was used as an additive. The stability constants for synergistic adducts at both places were almost the same, and hence it was concluded that the light and shade effect occurs in bonds between the central iron(II) and TTA anions.
Generation, ESR Spectra, and Isolation of N-(Arylthio)-2,4,6-triarylphenylaminyl Radicals. Influence of the Substituents on the 2,4,6-Triphenyl Groups on the Stabilities of Radicals
Authors: Miura Yozo , Kitagishi Yuichi , Ueno Sadaharu 
Published: August 2006

Abstract
Three N-(Arylthio)-2,4,6-tris(4-methylphenyl)-, three N-(arylthio)-2,4,6-tris(3-chlorophenyl)-, and five N-(arylthio)-2,4,6-tris(4-chlorophenyl)phenylaminyl radicals have been generated by PbO2 oxidation of the corresponding N-(arylthio)-2,4,6-triarylanilines and their isolation has been carried out. When electron-donating methyl groups were substituted at the p-positions of the 2,4,6-triphenyl groups, the aminyls were less stable, and only one could be isolated as radical crystals. On the other hand, when chloro atoms were substituted at the m- or p-positions of the 2,4,6-triphenyl groups, the aminyls were more stable and most were isolated. The isolated radical crystals were stable for a long period without any decomposition. The spin density distributions in the radicals are discussed on the basis of the ESR parameters.
Effects of Steric Bulkiness of Substituents on Quantum Yields of Photochromic Reactions of Furylfulgides
Authors: Yokoyama Yasushi , Inoue Tetsushi , Yokoyama Masato , Goto Takakazu , Iwai Takeshi , Kera Naohiko , Hitomi Isamu , Kurita Yukio 
Published: August 2006

Abstract
Furylfulgides with different sizes of alkyl substituents were synthesized and their photochromic properties were examined. While the quantum yield of coloring reaction increased and the quantum yield of the E-to-Z isomerization decreased as the steric bulkiness of the alkyl substitutent on the 2,5-dimethyl-3-furylmethylidene moiety increased, the bleaching quantum yield increased as the isopropylidene group was replaced by an adamantylidene group. Both effects worked independently, and a furylfulgide with an isopropyl group on the furylmethylidene moiety and an adamantylidene group in one molecule showed the coloring quantum yield of 0.51 (366 nm) and the bleaching quantum yield of 0.26 (492 nm) in toluene.
HLADH-Catalyzed Reduction of Cyclohexanone with NADH Regeneration by Alcohols: Effects of Reaction Conditions
Authors: Itozawa Toshiaki , Kise Hideo 
Published: August 2006

Abstract
The effects of alcohol structure and reaction conditions on the horse liver alcohol dehydrogenase-catalyzed reduction of cyclohexanone were investigated with in situ regeneration of NADH by alcohols. The rate of coupled reduction of cyclohexanone was much more strongly affected by the structure of alcohols than the reduction rate of NAD measured in the absence of cyclohexanone. Diols such as 1,4-butanediol or 1,5-pentanediol were the reductants of choice in terms of reaction rate and the yield of cyclohexanol. The effects of pH and buffer concentration on coupled reduction of cyclohexanone were parallel to the effects on NAD reduction. However, the dependency of coupled reduction of cyclohexanone on reaction temperature reflected the temperature-dependency of cyclohexanone reduction by NADH in the absence of alcohols. These results were discussed in terms of the difference of sensitivity to the reaction conditions of each oxidoreduction and of coupled oxidoreductions.