bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conductivity of N-Methylpyridinium Iodide and Its Methyl Substituted Derivatives in Water–Ethanol Mixture
Authors: Swain Ranjan Kumar , Behera B 
Published: July 2006

Abstract
The conductivity of N-methylpyridinium iodide (NMPI) and its methyl substituted derivatives at 2-, 3-, and 4-positions in water–ethanol solvent mixtures is reported at 25°C. The conductivity data are analyzed by the Shedlovsky method to get both Λ0 and KA, the association constant, simultaneously. The Λ0 values decrease or increase with increase or decrease of the viscosity of the solvent mixtures. The values of Λ0 and K are in the order of H&gt;3-&gt;4-&gt;2-. The Walden product Λ0η for these iodide salts behaves in a manner as is expected for highly hydrogen bonded water-alcohol mixtures. A mole fraction of 0.15 to 0.2 in ethanol indicates maximum interaction between water and ethanol. The values of Λ0 and KA indicate greater solvation and hence less ion-ion interaction in case of NMPI and 3-CH3 salts than 2- and 4-CH3 salts.
Thermospray Ionization Mass Spectrometry of Polydimethylsiloxane Antifoams
Authors: Nishimura Toshihide , Aoki Yukimi , Hiyama Yukio , Sonoda Akio 
Published: July 2006

Abstract
Mass Spectrometric characterization of several polydimethylsiloxane (PDSI) antifoams has been studied using a thermospray (TSP) ionization technique. The PDSI antifoams dissolved into an eluent were flow-injected to a TSP interface without column separation. A selective formation of PDSI ammonium adduct ions directly reflecting their molecular weight distributions was observed in the mass region up to 3500 daltons. Both cyclic PDSIs and fatty acid esters were detected for a water-dilutable antifoam and their relative abundances and species were characteristic to a particular formulation of antifoam emulsion. Thus TSP mass spectrometric technique seems suitable and useful for analysis of an aqueous antifoam sample to identify both its molecular weight distribution of PDSIs and a type of antifoam formulations used in various fields such as food and pharmaceutical industries.
Asymmetric Transformation of (RS)-1,2,3,4-Tetrahydro-3-isoquinolinecarboxylic Acid via Salt Formation with (1S)-10-Camphorsulfonic Acid
Authors: Shiraiwa Tadashi , Furukawa Tsuyoshi , Tsuchida Tamotsu , Sakata Shinji , Sunami Michio , Kurokawa Hidemoto 
Published: July 2006

Abstract
Asymmetric transformation of (RS)-1,2,3,4-tetrahydro-3-isoquinolinecarboxylic acid [(RS)-TIC] by use of (1S)-10-camphorsulfonic acid [(S)-CS] as a resolving agent gave a salt of (S)-TIC with (S)-CS with 90% optical purity in hexanoic acid. The TIC obtained from the salt was purified to give optically pure (S)-TIC in 80% yield based on the starting (RS)-TIC.
A Convenient Synthesis of Sulfones by the Oxone Oxidation of Sulfides in an Aprotic Solvent in the Presence of Clay Minerals
Authors: Hirano Masao , Tomaru Jun-ichirou , Morimoto Takashi 
Published: July 2006

Abstract
The title oxidation in dichloromethane in the presence of “wet”-montmorillonite and -kaolin afforded the corresponding sulfones in excellent to almost quantitative yield under neutral and mild conditions.
Absorption and Fluorescence Spectra of 1-Methyl-2(1H)-pyridinimines and 2-Methylaminopyridine–Acetic Acid Complex
Authors: Fujimoto Akira , Inuzuka Kozo 
Published: July 2006

Abstract
Upon the addition of acetic acid to 2-methylaminopyridine in isooctane, weak absorption and fluorescence bands appeared near 350 and 465 nm at the tail of the main bands, respectively. These new bands were attributed, on the basis of the spectral results of 1-methyl-, 1,3-dimethyl-, 1,4-dimethyl-, 1,5-dimethyl-, and 1,6-dimethyl-2(1H)-pyridinimines, and 1-methyl-2-methylimino-1,2-dihydropyridine, to have originated from 2(1H)-pyridinimine moiety (iminoform tautomer) in the 2-methylaminopyridine-acetic acid complex. In addition, the fluorescence quantum yields of the 1-methyl-2(1H)-pyridinimines in isooctane were shown to be very small.
Partial Oxidation of [Octakis(dodecyloxy)phthalocyaninato]zinc(II) with 2,3-Dichloro-5,6-dicyano-p-benzoquinone
Authors: Kasuga Kuninobu , Nakao Tadahiro , Mihara Takuya , Sogabe Kunihisa 
Published: July 2006

Abstract
While an organic oxidant such as 2,3-dichloro-5,6-dicyano-p-benzoquinone oxidized [Zn{Pc(OC12H25)8}] in a chloroform solution, it did not oxidize H2Pc(OC12H25)8 and [Cu{Pc(OC12H25)8}]. Oxidation was confirmed by the electronic and ESR spectra, as well as cyclic voltammograms. The electrical conductivity of the zinc(II) complex increased 105 times in partial oxidation.
Anisochrony in Rotatable Ligands and Symmetry Non-Equivalence Characterized by Subduction of Coset Representations
Authors: Fujita Shinsaku 
Published: July 2006

Abstract
A general method of characterizing symmetry equivalence and non-equivalence in a molecule is developed on the basis of the one-one correspondence between an orbit and a coset representation. This method provides us with a theoretical foundation to understand anisochrony in rotatable ligands. A given molecule is regarded as a combination of a three-dimensional skeleton and ligands. The ligand is referred to as a segment or a fragment according to its environment. Thus, the fragment is defined as a ligand-in-isolation; and the segment denotes a ligand built into a molecule. The symmetry of the ligand as a fragment is restricted to the local symmetry. This restriction is examined by using methyl and methylene ligands as examples. A methyl fragment has a homospheric C3v(/Cs) orbit that consists of three hydrogen atoms. On the other hand, a methylene fragment has an enantiospheric Cs(/C1) orbit that contains two hydrogen atoms. Such an orbit is incorporated into various molecules to afford restricted orbits, which are characterized by subduction of coset representations. The restricted orbits are discussed in terms of global and local orbits. This discussion provides a general approach to rationalize various types of anisochronies.
Extraordinary Coordination of Acetonitrile to Square-Planar, 1,4,8,11-Tetraazacyclotetradecanenickel(II) and (1R,4R,8S,11S)-1,4,8,11-Tetramethyl-l,4,8,11-tetraazacyclotetradecanenickel(II) Cations
Authors: Yokoyama Takashi , Iwamoto Etsuro , Kumamaru Takahiro 
Published: July 2006

Abstract
Coordination of dipolar aprotic solvents to the square-planar complexes of nickel(II) was investigated in nitrobenzene (NB) spectrophotometrically. Compared with N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), it was observed that acetonitrile (AN) was strongly coordinated to [NiL]2+ (L=1,4,8,11-tetramethyl-1,4,8,ll-tetraazacyclotetradecane). The stepwise coordination constants KNiS1 and KNiS2 (mol−1 dm3) for (1R,4R,8S,11S)-[NiL]2+ were found to be (1.6, 0.5), (1.0, 0.1), (3.4, 6.7), and (0.4, 1.9) for DMSO, DMF, AN, and benzonitrile, respectively. The KNiS2 values for nitriles are larger than the KNiS1 values, showing that nitriles are coordinated to the metal ion through π-back donation.
Silica-Supported Boron Phosphate Catalyst Prepared by Chemical Vapor Deposition
Authors: Sato Satoshi , Hasegawa Mitsuharu , Sodesawa Toshiaki , Nozaki Fumio 
Published: July 2006

Abstract
A silica-supported boron phosphate (BPO4) catalyst was prepared by chemical vapor deposition (CVD) using mixtures of boron triethoxide and phosphoryl trimethoxide. Both the amount and the P/B ratio of deposited BPO4 were changed with the CVD temperature and time. At the optimum CVD temperature of 300°C, the amount of deposited BPO4 was linearly increased with the CVD time. When alkoxide mixtures with the desired P/B ratio were used as CVD sources at 300°C, the expected P/B ratios were available. At CVD temperatures below 300°C, neither a sufficient amount nor a desired P/B ratio was given. On the other hand, above 325°C, the deposition was suppressed by blocking the micropore of silica, especially for long-time CVD operation, owing to the too fast deposition. Although the resulting surface compound was amorphous, it was revealed to have microstructures of BPO4 by means of a 31P NMR measurement. The amorphous BPO4 dispersed highly on silica exhibited a high catalytic efficiency for the isomerization of 1-butene and a simultaneous oligomerization of 1-butane in comparison with a catalyst prepared by the conventional impregnation method.
Application of the SPE Method to Organic Electrochemistry. XI Influence of the Solvent on the Electrooxidation of Cinnamyl Alcohol on Mn, Pt–Nafion
Authors: Chen Zhen , Mizoe Toshiyuki , Ogumi Zempachi , Takehara Zen-ichiro 
Published: July 2006

Abstract
The influence of organic solvents on the electrooxidation of cinnamyl alcohol on Mn, Pt–Nafion has been investigated. Though tetrahydrofuran (THF) gave a high current efficiency (90%), carbon tetrachloride gave a low current efficiency (&lt;20%). The importance of a co-solvent for the SPE electrolyzer was proposed and substrate transport to the active site located at the interface platinum/ionic cluster region was enhanced by solvents miscible with water. Though THF behaved as a good co-solvent, carbon tetrachloride did not. A composite electrode deposited with platinum on both surfaces of Nafion was applied to oxidation. The cell voltage was as low as 2 V.
Photocatalysis on Native and Platinum-Loaded TiO2 and ZnO Catalysts —Origin of Different Reactivities on Wet and Dry Metal Oxides—
Authors: Anpo Masakazu , Chiba Katsuichi , Tomonari Masanori , Coluccia Salvatore , Che Michel , Fox Marye Anne 
Published: July 2006

Abstract
Substantial differences in photocatalytic reactivity were observed on powdered TiO2 and ZnO, both Pt-loaded and unloaded, in the photocatalytic hydrogenation of CH3C≡CH and C3H6 in the presence of H2O. Similar reactivity was observed, however, in the photocatalytic oxidation of i-C4H8 and C3H6 by O2 on these same catalysts. Photoluminescence of TiO2 and ZnO in the presence and the absence of H2O and/or O2 indicate that H2O causes a downward band bending to increase the efficiency of recombination of photogenerated electrons and holes, with a greater effect being observed on ZnO than on TiO2. These results, together with the direct detection of reaction intermediates by ESR, are rationalized by differences in the yields of the photogenerated intermediates, i. e., H (formed from trapped electrons) and OH (formed from trapped holes). The steady state concentrations of these intermediates depend on the degree of the positively-charged adducts on the surfaces of these oxides. The addition of O2 causes an upward band bending of the oxide and suppresses recombination of photo-generated electrons and holes, by formation of negatively-charged surface adducts. With similar degrees of band bending, TiO2 and ZnO produce almost the same photocatalytic reactivities as are observed for these oxides as dry systems.
Conversion of Hydroxyl Groups in Alcohols to Other Functional Groups with N-Hydroxy-2-thiopyridone, and Its Application to Dialkylamines and Thiols
Authors: Togo Hideo , Fujii Misa , Yokoyama Masataka 
Published: July 2006

Abstract
The radical decarboxylation reaction of N-alkoxyoxalyloxy-2-thiopyridone which was prepared by the reaction of alcohol, oxalyl chloride, and N-hydroxy-2-thiopyridone was studied both in the absence and presence of olefinic compounds. The same reactions with olefinic and acetylenic alcohols gave the corresponding lactone derivatives. On the other hand the unsymmetrical alkyl 2-pyridyl disulfides were obtained by the same reaction with aliphatic thiols.
Selective Deoxygenation of Various N–O Bonds Catalyzed by Rhodium Carbonyl Clusters in the Presence of H2O and CO and Their Heterogenization Using Amino-Substituted Polystyrenes
Authors: Kaneda Kiyotomi , Fujita Kazuo , Takemoto Tetsuya , Imanaka Toshinobu 
Published: July 2006

Abstract
Catalytic deoxygenation of various N–O bonds using rhodium carbonyl compounds under a water gas shift reaction was studied. A catalyst system of Rh6(CO)16 and N,N,N′,N′-tetramethyl-1,3-propanediamine was found to have high activities for the following deoxygenations: 1) conversion of nitrobenzenes to anilines, 2) aliphatic nitro compounds to nitriles, 3) oximes to nitriles, 4) hydroxylamines to amines, and 5) amine oxides to amines. The above-mentioned rhodium catalyst system was heterogenized by using amino-substituted polystyrenes. Rh6 and Rh14 carbonyl clusters of [Rh6(CO)15H]−, [Rh6(CO)15]2−, and [Rh14(CO)25]4−, were formed on the polymer surface. The characteristic features of the catalysis of the polymer-bound rhodium cluster complexes are described in relation to the corresponding homogeneous ones.
Synthesis of α,ω-Diamino Acids via Amidocarbonylation Reaction: Novel Synthesis of Lysine, Ornithine, and Their Analogs
Authors: Amino Yusuke , Izawa Kunisuke 
Published: July 2006

Abstract
α,ω-Diamino acid derivatives, such as lysine and ornithine, were synthesized via amidocarbonylation (cobalt-catalyzed formation of N-acyl α-amino acid from aldehyde, amide and carbon monoxide) of ω-(phthalimido)alkanals in good yield. The phthalimido group was proved to be intact under the conditions of amidocarbonylation. The hydroformylation-amidocarbonylation of N-phthaloyl-β,γ- and N-phthaloyl-γ,δ-unsaturated amines proceeds very nicely to give α,ω-diamino acid derivatives with good selectivity. Selective deprotection of α-N-acyl-ω-N-phthaloyl α,ω-diamino acids was achieved using hydrazine for the N-phthaloyl group and aminoacylase for the N-acetyl group to afford the optically active α,ω-diamino acid, respectively.
A Study of the Reduction of Chelated Palladium on Mercury Electrode
Authors: Lai C K , Wang Y Y , Wan C C 
Published: July 2006

Abstract
This paper investigates the reduction kinetics and mechanism of Pd(II)–ethylenediamine with cyclic voltammetry and normal pulse polarography techniques. The results indicate that the reduction is an irreversible process. The major kinetic parameters and diffusion coefficients of Pd(II)–ethylenediamine and other Pd(II)–aliphatic diamine complexes are reported. The influences of concentrations, pH values, and ligand structures on the reduction of Pd(II) complex are also discussed. The electrochemical reaction orders with respect to ethylenediamine and Pd(II)–ethylenediamine are found to be 0 and 1, respectively and these reaction orders demonstrate an undissociated complex reduction mechanism. Finally the iodide effect on normal pulse polarography is studied. The increase in current when iodide is added implies that the reduction is via the outer sphere path way.
Chemical Shift Standards in High-Resolution Solid-State NMR (1) 13C, 29Si, and 1H Nuclei
Authors: Hayashi Shigenobu , Hayamizu Kikuko 
Published: July 2006

Abstract
The resonance frequencies of 13C, 29Si, and 1H nuclei in pure tetramethylsilane have been measured accurately by spinning the liquid sample at the magic angle, which are free from the effects of the bulk magnetic susceptibility and the solvent. Using the above resonance positions, the chemical shifts of several second shift-standard materials have been determined with much improved accuracy and precision.
The Reaction of Diphenyl(trimethylsilylmethyl)phosphine with Carbonyl Compounds in the Presence of Fluorides
Authors: Kawashima Takayuki , Mitsuda Noriaki , Inamoto Naoki 
Published: July 2006

Abstract
Diphenyl(trimethylsilylmethyl)phosphine (1) was allowed to react with benzophenone in the presence of CsF in N,N-dimethylformamide to give a mixture of methyldiphenylphosphine (2), (2,2-diphenyl-2-trimethylsiloxyethyl)diphenylphosphine (3) and (2-hydroxy-2,2-diphenylethyl)diphenylphosphine (4) in good yield. The use of about 10 mol% of CsF gave 3 with fairly good selectivity. The reaction with benzaldehyde gave a similar result, but only protodesilylation occurred in the reaction with enolizable carbonyl compounds.
Synthesis of Lateral Root-Inducing Compounds Using an Efficient Coupling Reaction of Chiral Triflates
Authors: Kotsuki Hiyoshizo , Miyazaki Aya , Ochi Masamitsu , Sims James J 
Published: July 2006

Abstract
Lateral root-inducing compounds, isolated from the bacterium Erwinia quercina, have been synthesized by using a coupling reaction of chiral triflates derived from l- or d- tartrates and their biological activities examined.
Photoinduced Intramolecular Cyclization Reaction of 2-(2-Alkenoyl)-3-isopropylthio-1,4-benzoquinones to Heterocyclic Compounds
Authors: Iwamoto Hidetoshi , Takuwa Akio 
Published: July 2006

Abstract
Irradiation of 2-acryloyl- and 2-(1-cycloalkenylcarbonyl)-3-isopropylthio-1,4-benzoquinones in benzene gave tricyclic and tetracyclic compounds in good yields, respectively.
Indium-Induced Reaction of Phenacyl Iodide. Deiodinative Dimerization to β,γ-Epoxy Ketone and Aldol Condensation with Aldehydes
Authors: Araki Shuki , Butsugan Yasuo 
Published: July 2006

Abstract
The reaction of phenacyl iodide with indium metal gave 3,4-epoxy-1,3-diphenyl-1-butanone which, on treatment with silica gel, gave 2,4-diphenylfuran and 2,4-diphenyl-4-oxobutanal. Metallic indium as well as indium(I) iodide were found to mediate the aldol condensation between α-halo ketone and aldehyde.
Organophosphorus Chemistry. XV. The Reaction of 10-Dicyanomethylene-9(10H)-phenanthrenone with Alkyl Phosphites
Authors: Abdou Wafaa M , Ganoub Neven A F , Mahran Mohamed R 
Published: July 2006

Abstract
The titled compound 5a reacts with trialkyl phosphites and dialkyl phosphonates to give, in each case, two conformers (A+B) of the corresponding phosphonate 8 and 9. The yields of the two isomers were estimated on the basis of 31P NMR data. Besides, structures 8 and 9 were supported by analytical and spectroscopic measurements of the major isomer 8A and 9A. The rotational isomers were assigned in terms of the Newman projection and NMR data. Relative ratios were studied in the light of dynamic NMR spectroscopy.
Electrical Conductivity of Black Phosphorus-Germanium Compound
Authors: Maruyama Yusei , Inabe Tamotsu , He Lin , Terui Toshifumi , Oshima Kokichi 
Published: July 2006

Abstract
Single crystals of a new material, black phosphorus doped with germanium, have been prepared by a bismuth-flux method. Germanium atoms are incorporated into the black phosphorus in 2 to 4 atomic percent. The resistivity is reduced by two to three orders (ρ=6×10−3 Ω cm) compared with the pure black phosphorus, and its temperature dependence is metallic at low temperatures. There is no magnetoresistance up to 12 T at 0.6 K in striking contrast to the pure black phosphorus which shows negative magnetoresistance in this region. The crystal lattice constants decrease with germanium doping, especially in the interlayer direction. These facts indicate the enhanced three dimensionality with germanium doping.
Cobalt(III)-tren Complexes of 3-Formylcamphor
Authors: Nakano Yoshiharu , Yoshikawa Yuzo , Masuhara Shigeo , Sato Shoichi 
Published: July 2006

Abstract
3-Formylcamphor Co(III) complexes of a tripod-like ligand, tren, were prepared and the two possible geometrical isomers were separated successfully. The crystal structure of one of them was determined by X-ray diffraction. A red plate-like crystal was monoclinic, space group P21, a=12.401 (2), b=9.9400 (7), c=10.932 (1) Å, β=108.44 (1)°, and Z=2. The structure was refined to R=0.047 on 2818 reflections. The geometrical isomers were compared sepectroscopically.
Preparations, Properties, and Crystal Structures of trans-[Rh(CN)2(NH3)4]Cl·H2O and trans-[Rh(CN)2(en)2]Cl
Authors: Yoshida Kiyohiko , Kitada Takayuki , Odano Naomi , Kashiwagi Mayumi , Harada Kazumasa , Urushiyama Akio , Nakahara Masayoshi 
Published: July 2006

Abstract
Syntheses of the title new complex compounds of Rh(III) were successful. Single, sharp IR peaks of ν (C≡N) were observed at 2130 cm−1 (trans-[Rh(CH)2(NH3)4]Cl·H2O) and 2170 cm−1 (trans-[RH(CN)2(en)2]Cl), respectively. The values of the ligand field tetragonal parameter Dt were estimated to be −366 and −377 cm−1, respectively, based on the 1Ega (D4h)←1A1g Aig transition (37100 cm−1: trans-[Rh(CN)2(NH3)4]+; 37000 cm−1: trans-[Rh(CN)2(en)2]+). The X-ray crystal data are: for trans-[Rh(CN)2(NH3)4]Cl·H2O, orthorhombic, Cmcm, a=7.961(3), b=17.295(2), c=7.436(3) Å, Dc=1.79, Dm=1.79 g cm−3, Z=4; for trans-[Rh(CN)2(en)2]Cl, monoclinic, P21⁄n, a=9.665(4), b=9.107(3), c=6.779(3) Å, β=109.68(2)°, Dc=1.85, Dm=1.83 g cm−3, Z=2. The N≡C–Rh–C≡N sequence of trans[Rh(CN)2(NH3)4]+ lies in a line of m2m Symmetry in the crystal. The central Rh atom of trans-[Rh(CN)2(en)2]+ occupies the special position of inversion symmetry. The important geometrical data of the complexes are Rh–N=2.07(1), Rh–C=2.02(3) Å, N–Rh–N=88.0(5)° (trans-[Rh(CN)2(NH3)4]+) and Rh–N=2.080(3), 2.072(3), Rh–C=2.047(4) Å, N–Rh–N (within chelate ring)=82.7(1)° (trans-[Rh(CN)2(en)2]+).
Effect of Chloride Ion on Lead Signal Appearance in the Co-Existence of Iron in Electrothermal Graphite Furnace Atomic Absorption Spectrometry
Authors: Imai Shoji , Ichinoseki Masayoshi , Nishiyama Yasuko , Hayashi Yasuhisa 
Published: July 2006

Abstract
The atomic absorption signals for lead were measured in various chloride matrices at a charring temperature of 700 K. A typical double-peak signal was observed with iron(III) chloride, while a single peak was observed with iron(III) nitrate. At a charring temperature of 1440 K, the first peak disappeared and only the second peak remained; the atomization temperature of the latter was in agreement with that in the iron matrix. The larger content of the chloride ion increased the first peak absorption and decreased the second peak absorption without any shift of the peak temperatures, showing that one species for the second peak was converted to the same species for the first peak by the addition of a chloride ion. The appearance temperature of the first peak signal in the X−–Fe3+ matrix system increased in the order Cl−&lt;Br−&lt;I−. It was concluded that the appearance of the first peak is caused by the dissociation of lead halide.
Electronic Properties of One-Dimensional Iodine Complex. Benzo[b]phenothiazine–I2.5
Authors: Someno Taro , Hoshizaki Taketoshi , Kozawa Kozo , Uchida Tokiko , Hayashi Hakuro , Sugano Tadashi , Kinoshita Minoru 
Published: July 2006

Abstract
One-dimensional metallic conductance was observed along the c axis of a single crystal of benzo[b]phenothiazine–iodine complex, (B[b]PT)2(I3−)(I)2, the crystal structure of which was preliminarily determined by X-ray analysis. Its metal-insulator transition was observed around 235 K, and the sign of the carriers seemed to be positive above 250 K. From the reflection spectra, with polarized light parallel to the c axis, a plasma-edge-like dispersion was observed in near IR region. Several parameters were evaluated by assuming a tight binding band model. The EPR spectra of this complex consist of only one broad signal (peak-to-peak width at room temperature 250×10−4 T) in the temperature range from 4 K to 296 K (g=1.998±0.002).
Photoreduction and Emission of Solid Europium(III) Chloride in KBr by Laser Irradiation at 308 nm
Authors: Yamada Yasuhiro , Ohno Shin-ichi 
Published: July 2006

Abstract
The emission and transient absorption spectra of solid europium irradiated with laser light at 308 nm were measured. EuCl3·6H2O in a KBr disk was photoreduced to form excited Eu2+, and the emission from excited Eu2+ was observed directly after a reduction of Eu3+. Since Eu2+ was not stabilized in the KBr disk sample, it oxidized rapidly to form Eu3+. From a discussion concerning the temperature dependence of the rate constants of the reduction and deexcitation, it is shown that the reduction rate increases at higher temperature.