bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Raman Spectra of Cobalt(III) Complexes. V. Differentiation between Two cis(a) Isomers of [Coa2(NH3)2(en)] Type Complexes (a=NO2− and CN−)
Authors: Kanamori Kan , Bansho Ikuko , Kawai Kiyoyasu , Akamatsu Keiji , Shimura Yoichi 
Published: July 2006

Abstract
Three geometrical isomers of [Co(NO2)2(NH3)2(en)]+ were newly prepared. Two cis(NO2) isomers (trans(NH3) and cis,cis) were clearly differentiated on the basis of the polarizabilities of the Raman bands due to Co–N(NH3 and en) stretching vibrations. The Raman polarization measurement was also applied successfully to the determination of the geometrical configurations of two [Co(CN)2(NH3)2(en)]+ isomers. The structural assignments were substantiated by optical resolution of the cis,cis isomers of [Coa2(NH3)2(en)]+ (a=NO2− and CN−).
Nonacarbonyldiiron-, Pentacarbonyliron-, or Hexacarbonylmolybdenum-induced Reactions of 4,5-Polymethylene-substituted 2-Isoxazolines
Authors: Nitta Makoto , Yi Akihiro , Kobayashi Tomoshige 
Published: July 2006

Abstract
The reaction of 4,5-polymethylene-substituted 2-isoxazolines, 3-phenyl-3a,5,6,7a-tetrahydro-4H-pyrano[3,2-d]isoxazole or 3-phenyl-3a,4,5,6a-tetrahydrofuro[3,2-d]isoxazole, with [Fe2(CO)9], [Fe(CO)5], or [Mo(CO)6] resulted in the formation of 5-hydroxy-1-phenyl-1-pentanone or 4-hydroxy-1-phenyl-1-butanone, via the N–O and C–C bond cleavage of the 2-isoxazoline ring and the subsequent hydrolysis. The similar reaction of 7a-morpholino- and 7a-(1-pyrrolidinyl)-3-phenyl-3a,4,5,6,7,7a-hexahydro-1,2-benzoisoxazoles undergoes the N–O bond cleavage and, the subsequent elimination of the amino group or the C-3a–C-7a bond fission. Although the reaction of 6a-morpholino- and 6a-(1-pyrrolidinyl)-3-phenyl-3a,4,5,6a-tetrahydro-4H-cyclopent[d]isoxazoles with [Mo(CO)6] undergoes the N–O bond cleavage, and the subsequent elimination of the amino group or the C-3a–C-6a bond fission, the reaction of those 2-isoxazolines with [Fe2(CO)9] proceeds very slowly. The mechanisms are proposed for these reactions.
The Cyclodextrin–Quinone Inclusion Compounds in an Aqueous Solution at 77 K. II. 9,10-Phenanthrenequinone and Acenaphthenequinone
Authors: Kuboyama Akira , Matsuzaki Sanae Y 
Published: July 2006

Abstract
A complex formation between cyclodextrins (CD’s) and the two o-quinones (9,10-phenanthrenequinone (PHQ) and acenaphthenequinone (ANQ)) in a water–ethylene glycol 1 : 1 mixture glassy solution at 77 K was investigated using the nπ* phosphorescence spectra of these quinones. It was considered on the basis of the observed results that PHQ forms a 1 : 1 complex with γ-CD and ANQ a 2 : 1 complex with β-CD. The structures of these complexes are discussed. It was found that complexes between γ-CD and the PHQ– and ANQ– naphthalene charge-transfer complexes are also formed.
The Crystal and Molecular Structure of Tetrakis(μ-1-hydroxy-2-naphthoato)-bis{aqua(ethanol)(1-hydroxy-2-naphthoato)neodymium(III)}-Water–Ethanol (1/2/2), [{Nd[C10H6(OH)(COO)]3(H2O)(C2H6O)}2]·2H2O·2C2H6O
Authors: Ohki Yoshiyuki , Suzuki Yasuo , Takeuchi Toshio , Shimoi Mamoru , Ouchi Akira 
Published: July 2006

Abstract
The structure of the title complex was determined by the single-crystal X-ray-diffraction method. It is triclinic, with the space group P\bar1; the cell constants were a=12.529(2), b=15.044(4), c=10.063(1) Å, α=104.15(2), β=98.73(1), and γ=87.16(2)°; Z=1, and the final R value was 0.053. The central metal atom is in a tricapped trigonal-prism geometry and is ennea-coordinated with seven oxygen atoms of the carboxylate ligands and with each oxygen atom of one water and one ethanol molecule. The complex is dimeric and the metal atoms are bridged with four carboxylate ions; two of them act as bidentates, and the other two, as tridentates, where one oxygen atom is coordinated to both metal atoms. The other carboxylate ion makes a chelate ring with each metal atom. The dimer is connected through hydrogen bondings to the atoms on both sides along the c-axis.
Transformation of 3-(2,2-Dichloroethenyl)-2,2-dimethylcyclopropanecarboxylates to the Corresponding 2,2-Dibromoethenyl Analogs by Halogen Exchange Reaction
Authors: Matsui Kiyohide , Saito Akemi , Kondo Kiyosi 
Published: July 2006

Abstract
The title transformation is effected with aluminium tribromide or related reagents in over 80% yields without cis-trans isomerization or epimerization. Efficient removal of hydrogen bromide is essential for optimum yields of the desired products. Use of boron tribromide instead of aluminium tribromide results in opening of the cyclopropane ring with no halogen exchange.
Active Carbon-Supported Aluminium Copper(I) Chloride as Solid Carbon Monoxide Adsorbent
Authors: Hirai Hidefumi , Wada Keiichiro , Komiyama Makoto 
Published: July 2006

Abstract
Active carbon-supported aluminium copper(I) chloride (AlCuCl4) is prepared by mixing active carbon with toluene solution of AlCuCl4, followed by the removal of the liquid phase at 6 mmHg, 100 °C. The active carbon-supported AlCuCl4 rapidly adsorbs carbon monoxide (CO) at 20 °C under 1 atm from 9:1 CO–N2 mixture and the equilibrium molar ratio of adsorbed CO to AlCuCl4 is 1.03. Adsorbed CO is desorbed either by reducing pressure or by elevating temperature. In the second adsorption, which is carried out after the desorption at 6 mmHg, 20 °C for 10 min, the molar ratio of adsorbed CO to AlCuCl4 is 0.51. The molar ratios are constant at 0.51 in the third and later adsorptions. The CO adsorbing ability of the active carbon-supported AlCuCl4 remains virtually unchanged on repeated contacts with nitrogen gas containing 9000 ppm of water.
Polymer-Protected Metal Complex for Gas Separation. II. Cross-Linked Polystyrene-Supported Aluminium Copper(I) Halide as Solid Carbon Monoxide Adsorbent
Authors: Hirai Hidefumi , Hara Susumu , Komiyama Makoto 
Published: July 2006

Abstract
Macroreticular (MR) type cross-linked polystyrene-supported aluminium copper(I) chloride is prepared by refluxing MR type polystyrene (divinylbenzene content 20%), aluminium chloride, and copper(I) chloride in benzene, toluene, carbon disulfide, or dichloromethane, followed by evaporation of the liquid phase. All the polystyrene-supported aluminium copper(I) chloride exhibit rapid and reversible adsorptions of carbon monoxide (CO). For the adsorbent prepared by using toluene as solvent, the equilibrium molar ratio of adsorbed CO to the charged copper(I) chloride is 0.83 at 20 °C under 1 atm (initial partial pressure of CO: 0.90 atm). Desorption of CO is carried out at 7 mmHg, 20 °C for 10 min. The equilibrium molar ratio of adsorbed CO to the charged copper(I) chloride in the second adsorption is 0.56. In the following adsorptions, the equilibrium molar ratios are virtually constant at 0.56. Usage of either gel type cross-linked polystyrenes or a linear polystyrene in place of the MR type cross-linked polystyrene results in CO adsorbents having poor abilities with respect to both adsorption rates and capacities. The adsorbing capacities of the CO adsorbents prepared from aluminium halide, copper(I) halide, and the MR type cross-linked polystyrene decrease as follows: AlCl3–CuCl system&gt;AlBr3–CuBr system&gt;&gt;AlI3–CuI system≈AlCl3–CuI system≈AlI3–CuCl system≈0.
Electronic Properties of Black Phosphorus Single Crystals and Intercalation Compounds
Authors: Maruyama Yusei , Suzuki Setsuko , Osaki Tomoko , Yamaguchi Hizuru , Sakai Sumiko , Nagasato Kyoko , Shirotani Ichimin 
Published: July 2006

Abstract
Actual procedures for the preparation of black phosphorus single crystals by a bismuth flux method have been explored and the details are described. The anisotropy and the temperature dependence of the electrical conductivity and the Raman scattering spectra of the crystals obtained by the above-method have been measured. The reflection spectra of crystals which were prepared by a high pressure technique have also been observed and compared with the calculated data. Several preliminary attempts for synthesizing black phosphorus intercalation compounds have been carried out for the first time. Evidence for the intercalation by an X-ray analysis is presented.
ESR and Mössbauer Studies of Crystallization Process of Iron Phosphate Glass
Authors: Tanaka Katsuhisa , Soga Naohiro , Ota Rikuo , Hirao Kazuyuki 
Published: July 2006

Abstract
0.7Fe2O3–0.3P2O5 glass was prepared by using a twin-roller method and the crystallization process of this glass was followed by means of ESR and Mössbauer spectroscopy in order to understand the state and the behavior of iron ions in the glass. The ESR line shape of the quenched 0.7Fe2O3–0.3P2O5 glass was much broader than that of the crystallized glass heat-treated at 710 °C for 5 h. Moreover, the linewidth of Mössbauer spectra decreased monotonously through the crystallization process. These facts indicated that there existed a distribution of ligand fields around iron ions in the glass. The Mössbauer parameters, that is the isomer shift and the quadrupole splitting, of the 0.7Fe2O3–0.3P2O5 glass showed that Fe3+ ions in this glass were laid on distorted octahedral ligand fields. The magnetic interaction working in the 0.7Fe2O3–0.3P2O5 glass at room temperature was dipole–dipole interaction. Besides, the Mössbauer spectrum of the glass exhibited no internal field line at room temperature. Hence, the glass is considered paramagnetic at room temperature. At the first stage of crystallization process, the α-Fe2O3 particles precipitated were sufficiently small and so the specimen was superparamagnetic, as revealed from the ESR and Mössbauer spectra of heat-treated specimens.
Synthesis of Stable 1,2-Diazocines, 4,7-Disubstituted 3,8-Diaryl-1,2-diazacycloocta-2,4,6,8-tetraenes, and Their Thermolysis
Authors: Yogi Seiichi , Hokama Kozo , Ueno Kazunori , Tsuge Otohiko 
Published: July 2006

Abstract
Stable 1,2-diazocines, 3,8-diaryl-4,6-dichloro-1,2-diazacycloocta-2,4,6,8-tetraenes, were prepared via a chlorination–dehydrochlorination sequence starting from readily-available 3,8-diaryl-1,2-diazacycloocta-2,8-dienes. When reacted with metal carboxylates in benzene under reflux, the dichloro-1,2-diazocines were converted into stable 4-acyloxy- and/or 4,7-bis(acyloxy)-1,2-diazocines. On the thermolysis in toluene under reflux, all the diazocines gave only pyridine derivatives with extrusion of the corresponding benzonitriles. The thermal behavior of the diazocines are also discussed.
Anthracene Derivatives as Acceptors of the Reaction Intermediate Generated by the Decomposition of Tropone Tosylhydrazone Sodium Salt. Regioselective Cycloaddition Reactions of Cycloheptatrienylidene or 1,2,4,6-Cycloheptatetraene with 9-Substituted Anthracene Derivatives
Authors: Saito Katsuhiro , Ishihara Hiraku 
Published: July 2006

Abstract
The rearrangement of the carbene, cycloheptatrienylidene, to the allene, 1,2,4,6-cycloheptatetraene, was investigated. Tropone tosylhydrazone sodium salt, the precursor of cycloheptatrienylidene was decomposed in the presence of various kinds of 9-substituted anthracene derivatives to afford cycloaddition products, whose structures show that the carbenic carbon atom or the allenic carbon atom of the carbene or the allene attacks the carbon atoms at the 10-position of the anthracenes. It is obvious that the electronic natures of the substituents on the anthracenes have no effect on the regioselectivity of the addition reaction, suggesting that the reaction proceeds via 1,2,4,6-cycloheptatetraene, which is derived from the cycloheptatrienylidene initially generated from the tosylhydrazone.
NMR Study on Inclusion Complexes of l-Phenylalanine and Aspartame with Cyclodextrins in Aqueous Solution
Authors: Takahashi Shin-ichiro , Suzuki Ei-ichiro , Nagashima Nobuya 
Published: July 2006

Abstract
The interactions of Phenylalanine and Aspartame (N-l-α-Aspartyl-l-phenylalaninel-methyl ester, APM) with α- and β-cyclodextrins (CD) in aqueous solutions were investigated by 1H and 15N NMR techniques. The changes in chemical shift of CD protons on going from free CD to the mixture with phenylalanine and APM indicate that the phenyl ring is included in the cavity of CD in the complex states. The changes in the chemical shift of the β-protons of phenylalanine and APM following the binding to α- and β-CD indicate that the simple association constants (Ka) are not applicable to these systems except for the case of APM/β-CD (Ka=90), and that the large changes of the rotamer fractional population of APM side-chain occur for APM/β-CD system. The analysis with Asp–Phe(15N)–OMe suggests that the torsional angles of the main chain of APM are unchanged on the formation of the inclusion complex. The low-field shifts of amide proton and its nitrogen resonances of Asp–Phe(15N)–OMe in the complex formation suggest that the amide part of APM is hydrogen-bonded to the C2 or C3 hydroxyl group of β-CD.
Voltammetric Determination of Dialkylammonium Ion in the Presence of Monoalkylammonium Ion by Addition of 18-Crown-6
Authors: Matsue Tomokazu , Akiba Uichi , Osa Tetsuo 
Published: July 2006

Abstract
The addition of 18-crown-6 to the electrolyte solution discriminated the reduction current peak for dialkylammonium ions from that for monoalkylammonium homologues, which made it possible to determine voltammetrically the dialkylammonium ions in the presence of the monoalkylammonium ions.
Solution Properties of Phycoerythrin. I. Characterization of Phycoerythrin
Authors: Mizuno Haruo , Iso Naomichi , Saito Takahide , Ohzeki Fumiaki , Ogawa Hiroo , Wang Zao 
Published: July 2006

Abstract
Phycoerythrin, one of the chromoproteins, from the red alga Porphyra yezoensis has been characterized by physicochemical measurement. The value of the sedimentation constant was 12s and it did not change with the change in pH from 5.4 to 6.8. This was assumed from the fact that the phycoerythrin did not undergo reversible dissociation-association reaction under these conditions. The weight average molecular weight of phycoerythrin was determined to be 2.2×105, and the intrinsic viscosity of phycoerythrin was determined to be 2.29×10−2 (10−1 dm3/g). From these values, the molecular shape of phycoerythrin was inferred to be globular based on the Scheraga-Mandelkern equation. The SDS-polyacrylamide gel electrophoresis of phycoerythrin showed that the phycoerythrin consisted of two subunits with molecular weights of 3.8×104 and 2.3×104. The sedimentation behavior of phycoerythrin suggested that the phycoerythrin solution was multicomponent. The phycoerythrin dissociated into two molecular species on treatment with sodium dodecyl sulfate. Their sedimentation constants were 12s and 2s. The 2s species was supposed to be phycoerythrin monomer.
The Effect of the Pressure on Proton Jumps in Ethanol–Water Mixtures at 25 °C
Authors: Ueno Masakatsu , Ito Kazunori , Tsuchihashi Noriaki , Shimizu Kiyoshi 
Published: July 2006

Abstract
The limiting molar conductances of hydrochloric acid in 0, 5, 10, 20, 30, and 80 mol% ethanol–water mixtures, and those of potassium chloride in 80 mol% of ethanol, were determined at 25 °C as a function of the pressure up to 2000 kgf cm−2 (1 kgf cm−2=0.9807×105 Pa) from the conductances measured in a dilute concentration range. In each solvent except for 80 mol% of ethanol, the limiting molar conductances of the proton, λ°(H+), are about four to six times larger than those of the potassium ion, λ°(K+), at all the pressures studied; in 80 mol% of ethanol, the value of λ°(H+) is very close to that of λ°(K+) at atmospheric pressure. The results suggest that the proton-jump mechanism acts in the water-rich region, but not in the ethanol-rich region. The excess proton conductances at an infinite dilution, λ°E, as estimated by [λ°E=λ°(H+)−λ°(K+)], were found to increase with an increase in the pressure. The pressure dependence of the excess proton conductances normalized to their values at 1 atm, λ°E(P)⁄λ°E(1), is most prominent in 5 mol% of ethanol; its magnitude decreases in this order; 5&gt;0&gt;10&gt;&gt;20&gt;&gt;30 mol% of ethanol. These results are discussed in relation to the effect of ethanol molecules on the water structure in the mixtures; a small addition of ethanol to water stabilizes the three-dimensional networks of water, while a further addition of ethanol makes it difficult to form them.
The Solvent Effects on the Optical Rotatory Properties of 1,7-Diaryl-5-hydroxy-3-heptanones and Related Compounds
Authors: Ohta Shinji 
Published: July 2006

Abstract
The ORD and CD curves of (S)-1,7-diphenyl-5-hydroxy-3-heptanone, (S)-1,7-bis(3,4-dimethoxyphenyl)-5-hydroxy-3-heptanone, and the related model compounds were obtained in selected solvents with different polarity. Causing the 1,7-diaryl-5-hydroxy-3-heptanones dextro-rotatory in chloroform was attributed to the formation of the intramolecular hydrogen bond between the C-3 carbonyl and C-5 hydroxyl groups, regardless of the presence of the phenyl groups. On the other hand, causing the compounds levo-rotatory in methanol was proved to necessitate simultaneously the breaking of the intramolecular hydrogen bond followed by solvation to the carbonyl and/or hydroxyl groups, as well as the presence of the phenyl groups. The ca. 30% of the solvent effect on the optical rotation was based on the change in the rotational strength associated with the n→π∗ transition of the carbonyl group as changing a solvent. The residual 70% was based on the change in the rotational strength associated with the electronic transitions at around 200 nm of the carbonyl and/or hydroxyl groups.
Synthesis of 2-(Alkyl and Aryl)thiazolo[4,5-b]quinoxaline Derivatives and Study of Their Fluorescent Properties
Authors: Phadke Ravindra Chintaman , Rangnekar Dinesh Wamanrao 
Published: July 2006

Abstract
Synthesis of 2-(alkyl and aryl)thiazolo[4,5-b]quinoxaline derivatives has been achieved by reacting 2, 3-dichloroquinoxaline derivatives with various thiocarboxylic acid amides. The resulting compounds have been studied for their fluorescent properties. Some of these compounds have been applied as fluorescent dyes on polyester fiber having fair dyeing properties.
Ab Initio MO Theoretical Studies on Direct Fragmentation of Organic Ions Produced by Electron-Bombardment
Authors: Ichikawa Hiroshi , Shigihara Atsushi 
Published: July 2006

Abstract
The possibility of bond-scission within a single vibration (direct fragmentation) in a molecular ion produced by electron-bombardment has been studied. MP2/6-31G* calculations have shown that a direct fragmentation in the ground-state ion is possible for the C–H bonds of hydrocarbons.
Synthesis and Properties of Manganese(III) Complex of Salen-Analog Containing Phenolic Pendant Group
Authors: Kanda Wakako 
Published: July 2006

Abstract
A manganese(III) complex, [Mn(sal-pen)], with N,N′-disalicylidene-2-methyl-4-(2-hydroxy-5-methylphenyl)-1,2-butanediaminate trianion (sal-pen3−) has been synthesized and characterized. The complex was shown to have a square-pyramidal structure with a pendant phenolate group at the apex. The electronic spectral and electrochemical properties of the complex are discussed in terms of an axial coordination of the phenolate group.
Simulation of Absorption Spectra of Polyenes Produced in PVA Film by Heating and Kinetics of Polyenes Formation
Authors: Maruyama Kazunori , Také Michio , Fujii Nobuyuki , Tanizaki Yoshié 
Published: July 2006

Abstract
Characteristics of absorption spectra of heated PVA film could be simulated as combinations of absorption spectra of free polyenes corresponding to the type –(CH=CH)n– (n=1–13). The change in concentrations of polyenes produced in PVA films was calculated by means of simulation. Each polyene –(CH=CH)n– was assumed to be produced by a first order reaction with rate constant kn with respect to the concentration of –(CH=CH)n−1–. kn values (n=1–13) at several temperatures were obtained. Arrhenius plots of kn from straight lines, giving activation energies 57–63 kJ mol−1 for the reaction catalyzed by H3PO4 and 94–100 kJ mol−1 for that by H2SO4. The activation entropies are negative in both cases.
Liquid Crystal Materials with Sulfur Atoms Incorporated in the Principal Structure. V. New Liquid Crystal Compounds; 2,5-Diaryl-1,3-Oxathianes
Authors: Haramoto Yuichiro , Sano Makoto , Kamogawa Hiroyoshi 
Published: July 2006

Abstract
2,5-Bis(p-substituted phenyl)-1,3-oxathianes (5), new liquid crystal compounds, and some corresponding 1,3-dioxanes were synthesized by the acetal formation reaction. The mesomorphic behaviors of compounds 5 were compared with those of the corresponding 1,3-dioxanes and 1,3-dithianes. Compounds 5 exhibited the lowest transition temperatures between nematic and isotropic phases. This seems to originate in the bend at the 1,3-oxathiane ring containing two heteroatoms, oxygen and sulfur, different in size. Compounds 5 also tend to exhibit supercooling states in nematic phase.
The Effect of the Substrate on the Epitaxial Growth of the Hexatriacontane Crystal
Authors: Ashida Michio , Ueda Yasukiyo , Yanagi Hisao 
Published: July 2006

Abstract
The epitaxial crystallization of hexatriacontane vacuum-evaporated onto a gold-covered KCl (001) surface was investigated as a function of the gold coverage. The hexatriacontane film on the KCl surface was composed of rod-like crystals taking the orientation of (110)H//(001)KCl and [001]H//[110]KCl. The film on evaporated gold film was composed of lamellar crystals taking the orientation of (001)H parallel to the substrate and a random orientation in the azimuthal direction. The hexatriacontane film evaporated on the substrate which was partly covered with gold particles was composed of both rod-like and lamellar crystals. When the coverage ratio of the gold particles was low, the lamellar crystals in the hexatriacontane film took the orientation of (001)H//(001)KCl and [110]H//[110]KCl. The numbers of lamellar crystals increased, and their orientation in the azimuth became more random, with and increase in the gold coverage.
The Unreactive Nature of N(24S) to Unsaturated Hydrocarbons
Authors: Umemoto Hironobu , Nakagawa Seiko , Tsunashima Shigeru , Sato Shin 
Published: July 2006

Abstract
The decay rates of ground-state atomic nitrogen in the presence of C2H4(ethene), Δ1,3-C4H6(1,3-butadiene), and C2H2(ethyne) were measured by using a pulse radiolysis-resonance absorption technique. It was found that the decay rates decrease drastically upon the addition of a small amount of I2, an efficient radical scavenger. This suggests that the decay of N(4S) in the absence of I2 is due to the reactions between the N(4S) and the free radicals. The rate constants for the reactions of N(4S)+C2H4, Δ1,3-C4H6, and C2H2 were estimated to be much less than 103 m3 mol−1 s−1. The rate constant for the N+I2→NI+I reaction was measured to be 2.4×104 m3 mol−1 s−1.
Total Synthesis of Neomethynolide
Authors: Inanaga Junji , Kawanami Yasuhiro , Yamaguchi Masaru 
Published: July 2006

Abstract
Neomethynolide (1), the aglycone of a twelve-membered ring macrolide, neomethymycin, was totally synthesized in its optically active form via 8,9-didehydro-1. The construction of the skeleton was carried out by condensing a stereoselectively synthesized fragment, 4-t-butyldimethylsiloxy-5-(2-methoxyethoxymethoxy)3-methyl-1-hexyne, with Prelog-Djerassi lactonic ester, and mixed anhydride method was used for the lactonization of an intermediary hydroxy acid. The full stereochemistry of 1 was established by this synthesis.