bluuebunny/crossref_metadata_2025 huggingface dataset:
Five- and Six-Coordinated Nitrosyl Iron(II) Complexes of Tetrakis (p-substituted phenyl)porphyrins. Substituent Effects on the EPR Parameters and the NO Stretching Frequencies
Authors: Yoshimura Tetsuhiko
Published: July 2006

Five- and six-coordinated nitrosyl iron(II) complexes of a series of tetrakis(p-substituted phenyl)porphyrins have been prepared. Their EPR and IR spectra have been measured and analyzed in order to elucidate the cis-effect of substituents on the axial nitrosyl ligand. As the first redox potentials of the free base porphyrins in the complexes became positive, the NO stretching frequencies increased in both five-coordinated and six-coordinated nitrosyl(porphyrinato)iron(II) complexes with a nitrogenous base at an axial site trans to the NO group. The positive shift of the redox potentials led to an increase in the EPR g values and hyperfine coupling constants at room temperature and at 77 K for the five-coordinated complexes, while it led to a decrease in g values and to a slight increase in hyperfine coupling constants for the six-coordinated complexes. These results are rationalized by invoking that, as the electron-withdrawing power of porphyrin peripheral substituents is enhanced, the iron-to-NO bond in both the five- and six-coordinated complexes is weakened and the iron-to-nitrogenous base bond in the six-coordinated complexes is strengthened. The difference in the cis- and trans-effects on the EPR parameters and NO stretching frequencies is also discussed.
Studies of Zone Melting. VII. Distribution Coefficients of the p-Nitrophenol–Naphthalene Eutectic System
Authors: Nojima Hidemoto
Published: July 2006

In a zone-melting experiment the effective and equilibrium distribution coefficients of p-nitrophenol in naphthalene have been determined by a method based on a determination of the solute concentration in the terminal one zone length after a single zone pass. The effective distribution coefficient (Ke) is determined by

K e=\frac2Z*+1\left{1−\frac1Z*−1(\fracCs*C0−1)\ight},

where C0 is the initial solute concentration; Cs* is the solute concentration described above and Z*=L⁄l−1⁄2; L and l denote the specimen and zone lengths, respectively. Further, the equilibrium distribution coefficient (Ko) is obtained as

K o=\frac2(Z*−B)Z*2−1

The constant (B) is related to the equation Cs*⁄C0=−AV+B, where V is the zone travel rate and A is also a constant. The obtained values of Ke and Ko agree with those determined by a method reported previously by the author.
Copper(II)-Rare Earth(III) (Ln=La, Gd, Lu) Binuclear Complexes of Bis[2-(3-carboxysalicylidene)aminoethyl]amine: Characterization and Specific Binding of Amino Alcohols
Authors: Sakamoto Masatomi , Hashimura Masayuki , Matsuki Kimihiro , Tajima Kunihiko , Ishizu Kazuhiko , Okawa Hisashi
Published: July 2006

Heterometal complexes, [CuLn(fsadien)(NO3)(H2O)n]·(H2O)5−n (Ln=La, Gd, or Lu), have been synthesized and characterized, where H4 fsadien denotes bis[2-(3-carboxysalicylidene)aminoethyl]amine. Based on electronic absorption and CD spectra, it was suggested that amino alcohols were specifically bound to the Cu(II)–Ln(III) heterometal center, through the nitrogen to the copper(II) ion and through the oxygen to the rare earth(III) ion.
A Pd(II)–Cu(II) Catalyst for the Kjeldahl Analysis of Nitrogen in Pyridines
Authors: Oishi Shigero , Komatsuzaki Hiroshi
Published: July 2006

A serious drawback of the Kjeldahl analysis of organic nitrogen, that pyridine derivatives were difficult to degrade to ammonia, was overcome by use of a Pd(II)–Cu(II) catalyst. Three hours of digestion at approximately 320°C using the catalyst were found to be sufficient for quantitative liberation of ammonia from pyridines.
17O NMR Study of Aqueous Electrolyte Solutions; Effect of KCl and NaCl on the 17O NMR Parameters of Water
Authors: Higashiyama Akira , Yamamoto Yasuhiko , Ch\={u}j\={o} Riichir\={o}
Published: July 2006

The aqueous solutions containing KCl or NaCl at various concentrations have been studied by 17O NMR. The line width of the signal increases and decreases with an addition of KCl above and below 55 °C, respectivly, and these results indicate that the effect of KCl on the water structure depends on temperature.
Conversion of (+)-8,11,13-Abietatriene into (15R)-16-Hydroxyferruginol and Its (15S)-Epimer
Authors: Matsumoto Takashi , Terao Hiromitsu , Imai Sachihiko
Published: July 2006

(+)-8,11,13-Abietatriene was converted into (15R)-16-hydroxyferruginol (1a) and its (15S)-epimer (1b) by the introduction of hydroxyl groups at the C-12 and C-16 positions.
Mercury(63P1)- and Cadmium(53P1)-Photosensitized Decompositions of Tetramethyltin
Authors: Yamamoto Shunzo , Inoue Satomi , Sueishi Yoshimi , Nishimura Norio
Published: July 2006

The mercury(63P1)-photosensitized decomposition of tetramethyltin (TMT) has been studied at 120 and 250°C and at pressures from 10 to 20000 Pa. The gaseous products detected were ethane, methane, and hydrogen. The yields of these products increased linearly with increasing reaction time and light intensity. From the effects of O2, NO, and H2 on the yield of ethane, the major primary reactions of the mercury-photosensitized decomposition of TMT were concluded to be processes with an Sn–C bond cleavage. The quantum yields of these products were independent of the TMT pressure at higher pressures than 200 Pa at 120°C. The quantum yield of ethane was also independent of the TMT pressure, while that of methane increased upon increasing the pressure at 250°C. The cadmium (53P1)-photosensitized decomposition of TMT has been studied at 280°C. The detected products were the same as those from the mercury-photosensitized decomposition, although the yield of hydrogen was very small. The pressure dependence of the yields of ethane and methane in the cadmium-photosensitized decomposition was very similar to those in the mercury-photosensitized decomposition of TMT at 250°C.
Hydration of Cyclic Oligo(oxyethylene) Compounds. Ultrasonic Velocities and Compressibilities of Binary Systems of Water with 12-Crown-4, 15-Crown-5, and 18-Crown-6
Authors: Miyazaki Yoshio , Matsuura Hiroatsu
Published: July 2006

Ultrasonic velocities of binary systems of water with 12-crown-4, 15-crown-5, and 18-crown-6 were measured and the adiabatic compressibilities were evaluated therefrom. The results indicate that the most compacted hydration structure is formed at the mole ratio, approximately 2:1, of water to oxyethylene monomer unit and that the poly(oxyethylene) chain enhances structuring of the liquid water network.
Miscibility of 2-(Octylsulfinyl)ethanol and Decylammonium Chloride in the Adsorbed Film and Micelle
Authors: Abe Koji , Matsukiyo Hidetsugu , Ikeda Norihiro , Aratono Makoto , Motomura Kinsi
Published: July 2006

The surface tension of the aqueous solution of 2-(octylsulfinyl)ethanol (OSE) and decylammonium chloride (DeAC) mixture was measured as a function of total molality and composition of surfactants at 298.15 K under atmospheric pressure. The total surface density and compositions in the adsorbed film and micelle of the mixture were evaluated by applying thermodynamic relations to experimental results. It was found that the phase diagrams obtained for the adsorption and micelle formation of the mixture are different in shape from those of 2-(decylsulfinyl)ethanol (DeSE)–OSE and dodecylammonium chloride (DAC)–DeAC mixtures which are assumed to mix ideally in the adsorbed film and micelle. Such a nonideal behavior was attributed to the attractive interaction between OSE and DeAC molecules. Further, the interaction is concluded to be more attractive in the micelle than in the adsorbed film.
Investigation of Ion and Solvent Transport Accompanying Redox Reactions of Polyvmylferrocene Films Using an in situ Electrochemical Quartz Crystal Microbalance Technique
Authors: Mizunuma Masaya , Ohsaka Takeo , Miyamoto Hirohisa , Oyama Noboru
Published: July 2006

The in situ electrochemical quartz crystal microbalance (in situ EQCM) technique has been applied to study ion and solvent transport accompanying the redox reaction of polyvmylferrocene (PVF) film coated on quartz crystal electrodes in aqueous and acetonitrile media. The dependence of apparent formal potentials (Epolyf)app of the Fc°/Fc+ redox couple (Fc° and Fc+ represent the reduced and oxidized sites, respectively, in the PVF film) upon the concentration of supporting electrolyte has been also examined in comparison with those of solution-phase ferrocene derivatives. The PVF film is ideally permselective to ClO4− anion in both aqueous and acetonitrile media. The PVF oxidation (or reduction of polyvinylferricenium ion) in aqueous media is accompanied by the ingress (or egress) of one ClO4− ion per redox site and some solvent (ca. one H2O per redox site). In LiClO4 acetonitrile media, during the oxidation process ClO4− ion with some solvent inserts into the film and the reverse phenomenon occurs during the reduction process. The results demonstrate that a combination of the in situ EQCM measurement and the measurement of the dependence of (Epolyf)app on the concentration of supporting electrolyte makes possible to elucidate quantitatively the ion and/or solvent transport process across the polymer film/ solution interface during the redox reaction.
Synthesis and Characterization of Directly Linked Salen–Porphyrin System with Constrained Geometries
Authors: Maruyama Kazuhiro , Kobayashi Fumikazu , Osuka Atsuhiro
Published: July 2006

Novel heterobinucleating porphyrin complexes, in which porphyrin and salen [N, N′-disalicylidene-ethylenediamine] subunits were directly linked with restricted geometries, were synthesized. These complexes showed a small change in their UV-vis spectra and oxidation potentials, but the fluorescence of porphyrin was effectively quenched by the linked nickel–salen subunit.
Surface Active Properties of Heptyl β-d-Xyloside Synthesized by Utilizing the Transxylosyl Activity of β-Xylosidase
Authors: Shinoyama Hirofumi , Gama Yasuo , Nakahara Hisae , Ishigami Yutaka , Yasui Tsuneo
Published: July 2006

The surface-active properties of heptyl β-d-xyloside were investigated. The critical micelle concentration of this surfactant was determined to be 30 mM (M=mol dm−3). The corresponding molecular area at saturation adsorption, the micellar weight and the aggregation number were 43 Å, 20700 and 78, respectively. This surfactant was found to have a surface activity similar to that of octyl β-d-glucoside.
Preparation and Crystal Structure of a New Barium Niobium Sulfide, Ba9Nb4S21
Authors: Saeki Masanobu , Onoda Mitsuko
Published: July 2006

A new barium niobium sulfide, Ba9Nb4S21, was prepared by the reaction of CS2 with a mixture of BaCO3 and Nb2O5. Powder X-ray diffraction peaks and electron diffraction spots for the compound were indexable on the basis of a hexagonal cell with lattice parameters of a=6.9743(6) and c=21.599(2) Å. Refinement based on powder X-ray diffraction data suggested that the crystal structure belongs to the same series with those of Ba16.5Nb9S42 and Ba2NbS5 reported by Swinnea et al.
Ozone Fading of 2,2′-Dihydro Azo Copper Complex Dyes
Authors: Matsui Masaki , Tsubota Kenjiro , Shibata Katsuyoshi , Muramatsu Hiroshige
Published: July 2006

The reactivities of dyes with ozone were in the following order, Acid Blue 74>disodium 1-(2-hydroxyphenylazo)-2-naphthol-3,6-disulfonate>Direct Yellow 12>Acid Orange 7>disodium 1-phenylazonaphthalene-3,6-disulfonate-2,2′-diolatocopper(II)>Mordant Red 3>Basic Green 4. The reaction of disodium 1-phenyl-azonaphthalene-3,6-disulfonate-2,2′-diolatocopper(II) with ozone was retarded by the introduction of electron-withdrawing groups and 8-sulfonato group. The potassium sulfonate dye was less reactive than the sodium one. Ozonization of l-phenylazonaphthalene-2,2′-diolatocopper(II) gave phenol, 2-naphthol, and phthalic anhydride.
Preparation and Reactivities of (η3-1- and 2-Trimethylsiloxyallyl)Fe(CO)2NO Complexes. Intermediates Functioning as Equivalents of β- and α-Acyl Carbocations and Acyl Carbanions
Authors: Itoh Keiji , Nakanishi Saburo , Otsuji Yoshio
Published: July 2006

(η3-1- and 2-Trimethylsiloxyallyl)Fe(CO)2NO complexes were prepared by the reaction of the corresponding siloxyallylic halides with Bu4N[Fe(CO)3NO]. These complexes reacted with both of carbon nucleophiles and carbon electrophiles preferentially at the less hindered sites of the allylic ligands. In these reactions, (η3-1-trimethylsiloxyallyl)Fe(CO)2NO complexes served as synthetically equivalent synthons for both of β-acyl carbocations and j8-acyl carbanions and (η3-2-trimethylsiloxyallyl)Fe(CO)2NO complexes as both of α-acyl carbocations and α-acyl carbanions. The stereochemical courses of the reactions are described.
Synthesis and Reaction of trans-Dichlorobis(o-phenylenediamine)rhodium(III) Perchlorate with Some Oxidizing Agents
Authors: Furuhashi Akiko , Endo Kunihiko , Takagi Shiro , Yoshino Yukichi
Published: July 2006

A new rhodium(III) complex with o-phenylenediamine, trans-[RhCl2{C6H4(NH2)2}2]ClO4 was synthesized and the reaction with oxidizing agents studied. Due to coordination with the rhodium(III) ion the o-phenylenediamine (opd) was greatly stabilized against oxidation and the complex was oxidized slowly by periodate via intermediate radical complex to bis(o-benzoquinone diimine)dichlororhodium(III) complex which decomposed to the final products.
Michael Addition of Acyclic Lithium 1,3-Dien-2-olates with α,β-Unsaturated Esters, Ketones, and Diesters
Authors: Kanemasa Shuji , Kumegawa Masahiro , Wada Eiji , Nomura Masafumi
Published: July 2006

The Michael addition of lithium 1,3-dien-2-olates with α,β-unsaturated carbonyl compounds is described. With α,β-unsaturated esters the reaction was reversible even at −78°C, while kinetically controlled with α,β-unsaturated ketones or alkylidenemalonates. At room temperature, the initially formed Michael adducts undergo subsequent intramolecular Michael addition to give substituted cyclohexanone derivatives in a highly stereoselective manner. Mostly anti-selectivity has been observed for the initial Michael addition, and the intramolecular cyclization was cis-selective.
Preparation and Magnetic Properties of the Copper(II) Mixed Carboxylates with Haloacetate and Ammonioacetate
Authors: Emori Shuji , Yoshidzu Kayoko
Published: July 2006

Copper(II) mixed carboxylate compounds, CuX(X′CH2COO)(R3NCH2COO)·mH2O (X=C1, Br; X′=F, Cl; R=, CH3), were prepared, and then characterized by means of magnetic susceptibility and IR-spectroscopy. The mixed carboxylates with betaine have the copper(II) acetate-type dinuclear structures. The amount of spin-exchange coupling through betaine bridges was estimated.
Complex Formation of Poly(Acrylic Acid) with Lead(II) Ion
Authors: Hayashi Hiromichi , Komatsu Tsuyoshi
Published: July 2006

The equilibrium constants of Poly(acrylic acid)–Pb(II) complex formation reactions were evaluated from stoichiometric equations by means of pH titration with a Pb(II) ion selective electrode. The thermodynamic parameters were obtained from the temperature dependence of the equilibrium constants. The Poly(acrylic acid)–Pb(II) complexes seem to be stable due to an exothermic process.
Syntheses and Spectral Properties of New Nitrosyl-[poly(1-pyrazolyl)borato]ruthenium Complexes
Authors: Onishi Masayoshi
Published: July 2006

Trichloro(nitrosyl)ruthenium(III) was treated with alkali-metal or thallium poly(1-pyrazolyl)borates M(BRPz3) (Pz=1-pyrazolyl) to give new nitrosyl[poly(1-pyrazolyl)borato]ruthenium(III) complexes [RuCl2(BRPz3)(NO)] (1, R=Pz; 2, R=H). A similar reaction with thallium tris(3,5-dimethyl-1-pyrazolyl)hydroborate TlBH(3,5-Me2Pz)3 (3,5-Me2Pz=3,5-dimethyl-1-pyrazolyl) afforded the complex [RuCl2{BH(3,5-Me2Pz)3}(NO)] (3) as the minor product and the 3,5-dimethylpyrazole complex [RuCl3(NO)(3,5-Me2PzH)2] as the major one. The observation of ν(NO) bands over the range 1870 to 1900 cm−1 determined the NO+ linear coordination mode in these complexes, rather than NO− bent one. The ν(NO) values of 1–3 were larger than those of the corresponding known π-cyclopentadienyl analogues by ca. 90 cm−1, indicating a smaller degree of π-back donation of metal–NO bonds in the former complexes. 1H, 13C, and 1B NMR data of the new complexes are described. In 1H NOE measurements of 1, irradiation at a chemical shift of 5-H protons in the coordinated pyrazolyl groups induced a positive NOE on the 5-H proton in the uncoordinated group, and individual assignments of the pyrazolyl protons were carried out with the help of 1H–1H and 13C–H COSY.
Extraction-Spectrophotometric Determination of Osmium Using 4-(2-Pyridylazo)resorcinol
Authors: Dadfarnia Shayessteh , Shamsipur Mojtaba
Published: July 2006

An extraction-spectrophotometric method for the determination of trace amounts of osmium(VIII) is described. Osmium is quantitatively extracted from aqueous solutions at pH 3.0–3.5 into a 10 : 1 chloroform–methyl isobutyl ketone mixture with tetrabutylammonium bromide, followed by spectrophotometric determination, using 4-(2-pyridylazo)resorcinol as a metallochromic indicator. The orange-red mixed complex of osmium absorbs light at λmax=530 nm with a molar absorptivity of 2.5×104 dm3 mol−1 cm−1. Beer’s law is obeyed over the range 0.5–18 μg cm−3. The method has a wide range and is sensitive and free from interferences from many anions and cations, including some platinum metals.
Catalytic Oxidation of Naphthalene on Palladium in Cooperation with Copper(I)/(II) Redox Couple
Authors: Kuroda Yasushi , Kunai Atsutaka , Hamada Michiyuki , Kitano Tomoyuki , Ito Sotaro , Sasaki Kazuo
Published: July 2006

Catalytic oxidation of naphthalene in moist acetic acid solutions has been studied. The catalyst used was a silica-supported palladium which works in cooperation with the Cu+/Cu2+ redox couple. Products were 1-naphthol, 1,4-naphthoquinone and (E)-2-formylcinnamaldehyde with a total yield of more than 78% in which naphthoquinone shared 40%. Reaction mechanism has been discussed in comparison with that of benzene.
Synthesis of 5′-[1-(Methoxycarbonyl)-2-(p-methoxyphenyl)ethyl]-and 5′-[2-(methoxyphenyl)-1-(p-methoxyphenyl)ethyl]-2′,3′,4,4′,6′-pentamethoxychalcone
Authors: Obara Heitaro , Onodera Jun-ichi , Tsuchiya Mitsuhiro , Matsueda Hiroyuki , Sato Shingo , Matsuba Shigeru
Published: July 2006

5′-[1-(Methoxycarbonyl)-2-(p-methoxyphenyl)ethyl]- and 5′-[2-(methoxycarbonyl)-1-(p-methoxypheny)ethyl]-2′,3′,4,4′,6′-pentamethoxychalcone were synthesized.

The latter compound was completely identical with the methylated derivative of aglycone of safflomin C, a constituent of safflower (Carthamus tinctorius L).
Cationic Self-Diffusion in Ionic Plastic Phases of Thallium Nitrite and Nitrate and in Thallium Thiocyanate
Authors: Furukawa Yoshihiro , Nagase Hirokazu , Ikeda Ryuichi , Nakamura Daiyu
Published: July 2006

Cationic self-diffusion in the ionic plastic phases of TlNO2 and TlNO3 was investigated by measuring temperature dependences of the 203,205Tl NMR spin-lattice relaxation time and the electrical conductivity. The NMR results snowed that the Tl+ ions in these phases undergo rapid translational diffusion with the activation energy (Ea) of 48 and 77 kJ mol−1 for nitrite and nitrate, respectively. The Ea values agreed well with those obtained from the electrical conductivity, indicating that the cation is the electric carrier. The diffusion constants (D) estimated from the relaxation time and conductivity data were ca. 10−12 m2 s−1 at the respective melting point (Tm) of plastic phase. The tendency that D at Tm has the characteristic value given above is recognized for other ionic plastic phases so far reported. The Tl+ ionic conductivity in TlSCN, which makes no plastic phase, was reported in comparison.
Theoretical Study of Phenalenium Systems
Authors: Ghosh Biswanath , Ghosh Debranjan , Das Gupta Archana , Das Gupta Nanda K
Published: July 2006

Phenalenium systems have been studied using PPP method modified by Dewar et al. Ground state properties and other properties such as π*←π spectra, ionization potential, electron affinity, half-wave reduction potential, pi-dipole moment have been predicted and correlated with experimental ones where available. Stability and resonance energy have also been discussed.
Solvatochromism and Prototropism in 2-(Aminophenyl)benzothiazoles
Authors: Dey Joy Krishna , Dogra Sneh K
Published: July 2006

The absorption and fluorescence spectra of 2-(2-aminophenyl)-, 2-(3-aminophenyl)-, and 2-(4-aminophenyl)benzothiazoles (o-APBT, m-APBT, and p-APBT, respectively) have been studied in different solvents and at various acid/base concentrations. The ultraviolet and fluorescence spectra and the low pKa value for the monocation–neutral equilibrium have indicated the presence of an intramolecular hydrogen bond (IHB) in o-APBT in the S0 state. Excited state intra-molecular proton transfer (ESIPT) in o-APBT, gives rise to a non-fluorescent phototautomer. Large solvatochromic shifts in polar solvents have indicated the increase in the dipolemoment of m-APBT in S1 state. It has been observed that in protic solvents, m-APBT forms a complex with solvent molecule in the S1 state. The equilibrium constants for different prototropic equilibria of the molecules have been determined in both S0 and S1 states. The absorption and fluorescence spectra of the prototropic species have been explained and compared with those of 2-phenylbenzothiazole (2-PBT). The monocation (2) of p-APBT, formed by protonation at the –NH2 group is found to undergo structural reorganization leading to a quinonoid structure (2′). The absorption and fluorescence excitation spectra (recorded at 390 nm and 460 nm fluorescence bands) indicate the simultaneous presence of species (2) and (2′), the former being more favorable in protic and the latter in nonpolar solvents. The molecular orbital calculation (PPP) has been used to calculate the absorption spectra and the charge densities at the basic centers of the neutral molecules.
Viscometry of Isothermal Urethane Polymerization
Authors: Reji John , Ravindran P , Neelakantan N R , Subramanian N
Published: July 2006

The viscosity values of Indian Space Research Organization’s (ISRO) hydroxyl terminated polybutadiene (HTPB) at various temperatures, the isothermal viscosity changes during the curing reaction of ISRO–HTPB with dlisocyanatotoluene (TDI) with and without catalyst and with a filler, calcium carbonate have been studied. The effect of temperature on this curing reaction is determined. The viscosity–time profile has shown an anomalous behavior and an explanation is put forward on the basis of polyurethane–HTPB, TDI mixture interaction. The viscosity–time profiles are drawn using normalized coordinates, which is helpful to compare the relative viscosity build up over relative periods.
Interaction of Urea with p-Nitrophenol
Authors: Das Gupta Prabhat K , Moulik S P , Das A R
Published: July 2006

Urea(U) can abstract H+ ion from p-nitrophenol (PNP) forming a hydrogen bonded ion pair (proton-transfer complex PNP− ···H+U) of 1 : 1 stoichiometry with a formation constant 0.42 at 303 K. Infrared spectral measurements of the uronium phenolate and uronium nitrate have supported that the proton transferred from PNP is attached to the oxygen center of the amide. The needle shaped light yellow urea–PNP adduct is fairly stable under ordinary conditions decomposing at 398 K. The standard free energy, enthalpy, and entropy of formation determined from spectrophotometric and calorimetric methods have been found to be 3.62 kJ mol−1, −13.30 kJ mol−1, and −57.5 J mol−1 K−1, respectively at 303 K.
High-Performance Liquid Chromatographic Determination of Components in Eye Lotion Using Methoxy(3-morpholinopropyl)silanediyl Modified Silica Gel Column
Authors: Akiyama Shuzo , Nakashima Kenichiro , Yamada Kyoko , Shirakawa Nanako
Published: July 2006

A recently developed column packing material, methoxy(3-morpholinopropyl)silanediyl modified silica gel, was successfully applied to the separation and determination of components (pyridoxine, flavin adenine dinucleotide, cyanocobalamin, chlorpheniramine, naphazoline, and neostigmine) in an eye lotion, in a single analysis by a single buffer elution with UV detection.
Preparation of Optically Active Sulfoxides Bearing Heterocycles and Stereoselective Methylation Using Their α-Sulfinyl Carbanions
Authors: Sagae Takahiro , Ogawa Satoshi , Furukawa Naomichi
Published: July 2006

Optically active sulfoxides bearing heterocycles i.e., (1-methyl-2-imidazolyl)methyl and 2-thienylmethyl groups were prepared and their stereoselective methylations were conducted.
O-Ethoxycarbonyl Hydroximoyl Chloride as Nitrile Oxide Precursor
Authors: Shimizu Tomio , Hayashi Yoshiyuki , Furukawa Nobuhiro , Teramura Kazuhiro
Published: July 2006

O-Ethoxycarbonyl hydroximoyl chloride serves as a stable precursor for nitrile oxide and is converted into the 1,3-dipole when heated under reflux in pyridine.
Nickel-Catalyzed Epoxidation of Olefins with NaOCl
Authors: Yamazaki Shigekazu , Yamazaki Yasuyuki
Published: July 2006

Nickel complexes of bidentate heterocyclic amines such as 2,2′-bipyridine and 1,10-phenanthroline have been found to be active catalysts for the epoxidation of olefins with hypochlorite as terminal oxidant. Nickel complex of 1-methylimidazole which is monodentate ligand also indicated epoxidation ability.
Chemical Oxidation of Tetra-t-butylphthalocyanine and Its Complexes with Cobalt(II), Nickel(II), Copper(II), and Zinc(II)
Authors: Mu Ping , Nakao Tadahiro , Handa Makoto , Kasuga Kuninobu , Sogabe Kunihisa
Published: July 2006

While the title compounds were oxidized by NOBF4, DDQ only oxidized the cobalt(II) and zinc(II) complexes in dichloromethane. To confirm their chemical oxidation, a cyclic voltammetry was measured.
Effect of Solvents and Acridine on Dibenzothiophene Hydrodesulfurization
Authors: Nagai Masatoshi
Published: July 2006

A selective poisoning pattern was observed for the hydrodesulfurization of dibenzothiophene on the sulfided Mo/Al2O3 catalyst in the presence of acridine and the solvents xylene and tetralin, using a microreactor at 270–340°C and 10.1 MPa total pressure.
Addition Effect of NaF on the Deodorant Efficiency of an Iron Phthalocyanine Derivative
Authors: Enmanj Koe , Nishiyama Itsuo , Takahashi Kenzo , Sanoh Muneharu
Published: July 2006

A low temperature ESR spectrum shows that Fe(III) of an iron phthalocyanine derivative treated with NaF takes a high spin state. The deodorant efficiency of the derivative treated with NaF is three times higher than that without NaF treatment.
Femtosecond–Picosecond Laser Photolysis Studies on Reduction Process of Excited Benzophenone with Tertiary Aromatic Amines in Acetonitrile Solution
Authors: Miyasaka Hiroshi , Morita Kazuhiro , Kamada Kenji , Nagata Toshihisa , Kiri Manabu , Mataga Noboru
Published: July 2006

Photoreduction processes of benzophenone (BP)-N,N-diethylaniline (DEA) system in acetonitrile solution were studied by means of femtosecond–pecosecond laser photolysis and time resolved transient absorption spectroscopy. The reaction processes including the formation of geminate ion pairs (IP) by electron transfer (ET) between BP* and DEA at encounter followed by intra-IP proton transfer giving the ketyl radical (BPH·) were clearly observed in both triplet and singlet excited state, while the IP produced by excitation of the CT complex between BP and amine formed easily in more or less concentrated solutions did not give BPH·. In addition to the detailed investigations on the BP-DEA system, we made comparative studies on BP–tertiary aromatic amine systems including N,N-diethyl-p-toluidine, N,N-dimethylaniline, and N-methyldiphenylamine. We observed clearly the characteristic tendency that the proton transfer rate in the 3IP decreased with decrease of the oxidation potential of the amine. This result was interpreted as due to the increase of the inter-ionic distance in the 3IP with increase of the free energy gap for the charge separation at encounter.
Synthesis of 2,6-Dihydronaphth[1,2,3-cd]indol-6-ones
Authors: Arai Sadao , Yamauchi Sigeaki , Yamagishi Takamichi , Hida Mitsuhiko
Published: July 2006

The reaction of 1-aminoanthraquinone with benzyl chloride in KOH-DMSO system afforded 3,11b-dibenzyl-2-phenyl-2,3,7,11b-tetrahydroanthra[1,9-de][1,3]oxazin-7-one (5; 78% yield), whose structure was determined by single-crystal X-ray diffraction. The reaction of compound 5 with aluminium chloride gave 1-phenyl-2,6-di-hydronaphth[1,2,3-cd]indol-6-one (52% yield) having strong fluorescence.
Asymmetric Dipolar Cycloaddition of Nitrile Oxides to the α,β-Unsaturated Esters Bearing an Imidazolidine Chiral Controller at the β-Position
Authors: Kanemasa Shuji , Hayashi Takashi , Yamamoto Hidetoshi , Wada Eiji , Sakurai Tosio
Published: July 2006

Some α,β-unsaturated esters bearing an imidazolidine chiral controller at the β-position were employed in the asymmetric cycloaddition to nitrile oxides. Regio- and diastereoselectivities were both poor when the chiral controller was a perhydropyrrolo[1,2-c]imidazol-3-yl auxiliary, while the reaction of the esters bearing a C2-symmetric imidazolidine chiral controller was exclusively regioselective or diastereoselective depending upon the nature of N-substituent. The transition state was briefly discussed.
Silicon Effects. III. Rates and Products for Solvolysis of α-(Penta-methyldisilanyl)benzyl Halides and 1,1,2,2-Tetramethyl-1,2-disilaindan-3-yl Chloride. Structure and Stability of α-(Pentamethyldisilanyl)benzyl Cation in Solution
Authors: Shimizu Nobujiro , Kinoshita Chieko , Osajima Erika , Hayakawa Fumie , Tsuno Yuho
Published: July 2006

Detailed kinetic and product studies have been made on solvolysis of α-(pentamethyldisilanyl)benzyl halides (1a-X; X=Cl and Br) and 1,1,2,2-tetramethyl-1,2-disilaindan-3-yl chloride (2-Cl) in various solvents. The solvolysis of 1a-X at 25°C is characterized by (1) a complete 1,2-SiMe3 rearrangement in the products, (2) m (sensitivity to the solvent ionizing power Yx) values of 0.98 (X=Cl) and 0.91 (X=Br) for the solvolyses in aq acetone, (3) α-deuterium isotope effects of 1.167 and 1.163 for 1a-Cl in 97% aq 2,2,2-trifluoroethanol (TFE) and 40% aq ethanol respectively, and (4) substituent effect expressed by a Yukawa–Tsuno LArSR equation: logk⁄kH=−3.71 (σ°+1.16 Δ\barσR+) for the solvolysis of 1a-Cl and the p-Me, m-Me, p-Cl, and m-Cl derivatives in 40% aq ethanol. These findings are consistent with kc mechanism. The relative rates for 1a-Br, α-(trimethylsilyl)benzyl bromide, and α-(t-butyldimethylsilyl)benzyl bromide are 1.07×105 : 0.54 : 1.0 in 97% aq TFE at 25°C indicating solvolytic generation of α-(pentamethyldisilanyl)benzyl cation to be ca. 7 kcal mol−1 energetically more favorable than that of the corresponding α-(trialkylsilyl)benzyl cations. In contrast, 2-Cl solvolyzes 0.209 times less rapidly than does 2,2-dimethyl-2-silaindan-l-yl chloride in 97% aq TFE indicating that a β-Si-Si σ bond orthogonal to the leaving group does not enhance the rate of ionization at all.
Preparation of New Nitrogen-Bridged Heterocycles. 27. First Syntheses of 1,3-Thiazino[6,5-b]indolizine Derivatives
Authors: Kakehi Akikazu , Ito Suketaka , Sakurai Tosio , Urushido Kunio , Isawa Hidetoshi , Enomoto Manabu
Published: July 2006

Potassium 2-indolizinethiolates, generated in situ from the treatment of dialkyl 2-[(2-ethoxycarbonylethyl)thio]indolizine-1,3-dicarboxylates with potassium t-butoxide in N,N-dimethylformamide, reacted smoothly with various isothiocyanates and isocyanates with the elimination of alkoxide ions to give new heterocyclic compounds, alkyl 4(3H)-oxo-2-thioxo- and 2,4(3H)-dioxo-2H-1,3-thiazino[6,5-b]indolizine-10-carboxylates, in moderate to good yields. The structures of these l,3-thiazino[6,5-b]indolizine derivatives were determined mainly by elemental analyses and spectral inspections, and the structural assignment was finally confirmed by the single crystal X-ray analyses of two compounds.
Neighboring Effect of a Carbonyl Group in Base-Induced Wittig-Type Rearrangements of Poly(4-nitrobenzyloxy)tropones to Bis- and Mono(α-hydroxy-4-nitrobenzyl)tropones
Authors: Yin Bing Zhu , Mori Akira , Takeshita Hitoshi
Published: July 2006

The base-catalyzed rearrangement of bis- and tris(4-nitrobenzyloxy)tropones gave (α-hydroxy-4-nitrobenzyl)tropones through a Wittig-type mechanism. Only the 4-nitrobenzyloxy group adjacent to the carbonyl group migrated. The carbonyl group played a role in facilitating the rearrangement by chelation with the sodium on the adjacent carbanion.
Preparation of Ultrafine Particles of Copper by Reduction in a W/O Emulsion System
Authors: Itoh Hiroyuki , Miura Moto-o , Okamoto Reoki , Kikuchi Eiichi
Published: July 2006

Ultrafine particles (UFP) of Cu were prepared by reduction in a w/o emulsion system, in which Cu(II) ions dissolved in aqueous droplets were reduced by a reducing agent. This method gave a very narrow particle size distribution. Moreover, the average size of UFP could be controlled by choosing the concentration of Cu ions.
Cadmium (53P1)-Photosensitized Luminescence of Some Aliphatic Diamines
Authors: Yamamoto Shunzo , Sueishi Yoshimi , Nishimura Norio
Published: July 2006

The cadmium(53P1)-photosensitized luminescence of some aliphatic diamines was studied by a steady-illumination method at temperatures between 230 and 330°C. It was found that 1,2-ethylenediamine, N,N,N′,N′-tetramethyl-1,2-ethylenediamine, 1,3-propanediamine, and N,N,N′,N′-tetramethyl-1,3-propanediamine have two emission bands (wavelengths at the peaks of these bands are about 450 and 550 nm), while N,N,N′,N′-tetramethylmethanediamine, N,N′-dimethylpiperazine, and triethylenediamine have only a short-wavelength band. From the temperature and pressure dependences of the emission intensities of the two bands, it had been concluded previously that these bands could be assigned to two kinds of 1 : 1 exciplexes between an excited cadmium atom and a diamine molecule. From the temperature dependence of the equilibrium constants between the two exciplexes which had been obtained from the ratio of the emission intensities of the two bands, the enthalpy and entropy changes of the equilibrium were evaluated. The cyclic exciplexes assigned to the long-wavelength band have smaller enthalpies and entropies than do the noncyclic exciplexes assigned to the short-wavelength band.
Acid-Promoted Oxidations of an NAD(P)H Model with Hydrogen Peroxide and Molecular Oxygen
Authors: Tamagaki Seizo , Mimura Takashi , Tagaki Waichiro
Published: July 2006

The HClO4-catalyzed H2O2- and O2-oxidations of a dihyropyridine in acetonitrile were mechanistically investigated; the H2O2-oxidation under nitrogen followed a heterolytic course to yield the corresponding pyridinium salt along with a monooxygenated product, while the O2-oxidation produced the pyridinium salt and H2O2 via a radical-chain pathway in which H2O2 is not only merely the product but also an initiator.
Synthesis of Naphth[1,2,3-cd]indol-6(2H)-one Derivatives and Their Fluorescence Properties
Authors: Arai Sadao , Yamauchi Shigeaki , Moriya Yuriko , Tanaka Tei-ichi , Yamazaki Yoko , Inoue Haruo , Yamagishi Takamichi , Hida Mitsuhiko
Published: July 2006

Highly fluorescent 1-phenylnaphth[1,2,3-cd]indol-6(2H)-one (3b) and its 7-chloro and 7-amino derivatives were synthesized by reaction of 1-aminoanthraquinones with benzyl chloride in KOH–DMSO system, followed by treatment with aluminium chloride. The compound 3b was easily N-alkylated with various alkyl halides in KOH–DMSO system. The fluorescence quantum yields (Qf) of naphth[1,2,3-cd]indol-6(2H)-one derivatives 3 were high (0.5–0.7), except for 7-amino derivatives which did not fluoresce. The Qf of 7-chloro derivative (3d) was strongly dependent on solvent: 0.37 in ethanol; 0.02 in acetonitrile; 0 in benzene. The compounds 3 were demonstrated to be efficient laser dyes for 500–550 nm region.
Mechanistic Study of the Hydrogenation of Carbon Dioxide to Methanol over Supported Rhenium and Copper–Zinc Catalysts
Authors: Xu Zheng , Qian Zaihu , Hattori Hideshi
Published: July 2006

The reaction of a mixture containing 13CO, CO2, and H2 was carried out in order to elucidate the reaction mechanisms of carbon dioxide hydrogenation to methanol over supported Re catalysts as well as Cu–Zn oxide catalysts. The reactions of formic acid and formaldehyde with hydrogen were also examined. From the incorporation of 13C in the product methanol, it could be distinguised whether the carbon dioxide hydrogenation to methanol proceeds through formation and successive hydrogenation of CO or by direct hydrogenation of CO2. Methanol is formed almost exclusively by direct hydrogenation of CO2 over CuO–ZnO based catalysts. However, the two reaction routes operate over Re/ZrO2 and Re/CeC2, the contribution of route via CO being higher over Re/ZrO2 than over Re/CeO2. The reactions of formic acid and formaldehyde with hydrogen suggest that the surface formate and the adsorbed formaldehyde are involved in the methanol formation, and that the conversion of the formate to the adsorbed formaldehyde is a key step.
Spin-Lattice Relaxation Time Measurements of Ions and Water Molecules Containing Spin 1 Nuclei in Lyotropic Liquid Crystalline Systems
Authors: Iida Masayasu , Tracey Alan S
Published: July 2006

The Jeener–Broekaert pulse sequence was applied to the 14N and 2H NMR measurement for studying the dynamic behavior of ions (ammonium and nitrate ions) and water molecules, respectively in lyotropic nematic liquid crystal solutions. The results showed that, in all cases except for the ammonium ion in alkaline solutions, the water molecules and the ions measured gave NMR spectra with properties characteristic of extreme narrowing conditions.
The Magnetic Properties of the 2-Pyridone Adducts of Copper(II) Benzoates and Related Copper(II) Compounds
Authors: Emori Shuji , Suenaga Hiroyuki , Goto Naomi
Published: July 2006

The 2-pyridone adducts of copper(II) benzoate, copper(II) 2-pyridinolate, and bis(adenme)copper(II) sulfate were prepared, and then characterized by means of magnetic susceptibility and IR spectroscopy. Their magnetic properties were correlated with the basicities and coordinate-bond lengths of the bridging ligands.
A Facile Reduction of Certain Schiff Bases with Di- and Trichlorosilanes
Authors: Okamoto Hidenori , Kato Shozo
Published: July 2006

The reduction of N-[(3-methoxy-2-thienyl)methylene]-2,6-dimethylaniline (2) by use of trichlorosilane proceeded smoothly in the presence of a catalytic amount of BF3·Et2O. The trichlorosilane/BF3·Et2O combination was applicable to the reduction of various Schiff bases. In the case of dichlorosilane, the reduction of 2 proceeded with a 90% yield without any catalysts.
Preparation of Stable 5,15-Dihydroporphyrin
Authors: Ono Noboru , Kaziro Hiroshi , Maruyama Kazuhiro
Published: July 2006

Very stable 5,15-dihydroporphyrin was perpared by the acid catalyzed reaction of dipyrromethane with two benzaldehyde molecules which were linked by an appropriate linkage.
Asymmetric Reduction of Carbon–Carbon Double Bonds of Conjugated Enones with Fermenting Bakers’ Yeast
Authors: Sakai Takashi , Matsumoto Syuji , Hidaka Syukou , Imajo Norihisa , Tsuboi Sadao , Utaka Masanori
Published: July 2006

Bakers’ yeast reduction of α-substituted or β,β-disubstituted α,β-unsaturated ketones gave saturated chiral ketones with excellent optical purity, while the β,β-disubstituted derivative remained intact.
SH2′ Type Reactions of Arenesulfonyl Chlorides with Allylic Compounds Catalyzed by a Ruthenium(II) Complex
Authors: Kamigata Nobumasa , Ishii Kimiko , Ohtsuka Takeshi , Matsuyama Haruo
Published: July 2006

In the presence of a catalytic amount of dichlorotris(triphenylphosphine)ruthenium(II), the reactions of arenesulfonyl chlorides with allyl phenyl sulfide and allyl phenyl selenide proceeded smoothly to give allyl phenyl sulfone in high yield as well as the corresponding diphenyl disulfide or diphenyl diselenide. An SH2′-type mechanism involving the arenesulfonyl radical is proposed.
Reactivity of Alkaneselenenyl Bromide: Conversion of Alcohols into the Corresponding Alkyl Bromides with Dialkylselenium Dibromide
Authors: Akabori Sadatoshi , Takanohashi Yoshinori
Published: July 2006

The reaction of alcohols with dialkylselenium dibromide gave the corresponding bromides in moderate to high yields. Alkaneselenyl bromide, produced by the thermal decomposition from dialkylselenium dibromide, acts as a brominating agent. The reaction of alcohols with dialkylselenium dichloride also afforded the corresponding chlorides, although the yields were relatively low compared with those of the bromide.
Photochemistry of Substituted 2-Benzoylcyclohexanones
Authors: Hasegawa Tadashi , Yang Yiming , Yoshioka Michikazu
Published: July 2006

The photoreactivities of substituted 2-benzoylcyclohexanones were distinguished as three different types; 1) the exclusive Norrish Type II cleavage when there were no alkyl groups on the 2- nor on the ortho-position, 2) the benzoyl group shift from the 2- to the 4-position when an alkyl group was present on the 2- and not on the ortho-position, and 3) 1,2,3,4,4a,9a-hexahydro-9(10H)-anthracenone derivative formation when an ortho-methyl group was present.
Comparison of the Temperature and Location Dependence of 1H and 13C NMR Shifts between Saturated 1,3- and 1,2-Diamines Coordinated to Low-Spin Tetracyanoferrate(III)
Authors: Kuroda Yoshitaka , Goto Masafumi , Sakai Tomoya
Published: July 2006

The temperature dependence of the 1H NMR for low-spin iron(III) complexes, [FeIII(CN)4(1,3-diamine)]−, with 1,3-propanediamine, (2R,4S)-2,4-pentanediamine, and (2R,4S)-2,4-pentanediamine were measured at 323–183 K. The coordinated amine segment, Fe–N(HN)2-C(Hα)2–C(Hβ)2, resonated in the following magnetic field regions at 323–183 K: Hαax, 7.2–20.5; Hβax, 10.8–35.0; Hβeq, 23.9–65.7; Hβmethyl, 1.8–9.9 ppm. All of the 1H signals moved in the downfield direction with a decrease in the temperature, and exhibited a non-Curie behavior. The HN shifts at 300 K were 110–279 ppm. The temperature and location dependence of the isotropic shift (δiso) for the 1H and 13C nuclei were accounted for by the combination of Fermi contact and dipolar contributions. The Fermi constants and spin populations were estimated for the 1H and 13C nuclei. Not only the spin polarization mechanism, but also a direct mechanism, were suggested for spin propagation from the FeIII to the respective atoms.
Kinetic Study of Casein Micelle Formation Observed by a Stopped-Flow Apparatus
Authors: Nishikawa Sadakatsu , Tatsusue Misa , Inoue Tadaomi , Yasunaga Tatsuya
Published: July 2006

The time dependent optical density changes were observed when aqueous solutions (Tris buffer) of sodium casein from milk were mixed with those of calcium chloride by a newly constructed stopped-flow apparatus which was controlled by an 8-bit microcomputer. Two approaches for single exponential decay curve analysis were used, i.e. the Guggenheim analysis and an analysis according to a linear relation between the time and the logarithm of the corresponding absorbance change, at a concentration range between 0.02–0.05 wt% of the casein and in that between 10–30 mmol dm−3 of calcium chloride at 25°C. The same time constants and reaction amplitudes were obtained from both analyses of the decay curves. The obtained rate parameters were found to be concentration dependent. The result was interpreted by a stepwise reaction mechanism for the formation of a casein aggregate. The rate-determining step was speculated to be the first step of the larger molecular aggregate of the casein according to the concentration dependence of the apparent rate constant and the reaction amplitude. The rate constant for the casein micellization could be approximately estimated as being of the order of 104 mol−1 dm3 s−1 at 25°C. The effects of NaCl, MgCl2, and CaBr2 on casein micelle formation were also examined; it was kinetically confirmed that only calcium cations played an important role in the formation of the casein micelle.
Photoelectron Emission Study of Iron(II) and Cobalt(II) Complexes in Aqueous Solution. Reorganization Energies
Authors: Watanabe Iwao , Ono Kaori , Ikeda Shigero
Published: July 2006

The photoelectron emission threshold energies of FeII and CoII complexes in aqueous solutions have been determined. The values could be successfully used for obtaining the reorganization energies in the one-electron oxidation reaction of these complexes. The obtained reorganization energies were found to be correlated with the rate constants of the electron-self-exchange reactions of FeII/FeIII and CoII/CoIII.
Conformational Stability of V-Amyloses and Their Hydration-Induced Conversion to B-Type Form as Studied by High-Resolution Solid-State 13C NMR Spectroscopy
Authors: Saitô Hazime , Yamada Junko , Yukumoto Tohru , Yajima Hirofumi , Endo Ryuichi
Published: July 2006

We have recorded 13C NMR spectra of several preparations of amorphous samples, V-amyloses and their hydrates to gain insight into their relative stability and subsequent hydration-induced conformational change. It was found that the 13C NMR line width of the iodine complex prepared as a precipitate in aqueous solution was the narrowest among these preparations, including the iodine complex formed from cast film. It is noteworthy that these V-amyloses are not always stable when they are equilibrated in an atmosphere of 96% R. H. in a desiccator and converted to B-type form, consistent with previous observation by Senti and Witnauer (J. Am. Chem. Soc., 70, 1438 (1948)). 2H NMR line shape and spin-lattice relaxation times were measured for partially deuterated V and B-type amylose samples containing DMSO-d6 and deuterium oxide, respectively, to explore the dynamics of the DMSO and water molecules bound to the polymer chains. It is unlikely that any drastic conformational change such as unfolding followed by refolding and plausible change of handedness is caused by such mild physical treatment as humidification. Therefore, it appears that the resulting B-type form should be ascribed to a left-handed single helix as a consequence of a slight modification of V-amylose, in contrast to the previous interpretation based on the data of X-ray diffraction and NMR studies. Gelation mechanism of amylose gel based on this view is also discussed.
Ring Transformation of 1-Substituted 3,5-Dinitro-4-pyridones to 4-Nitro-5(2H)-isoxazolone by Hydroxylamine
Authors: Ariga Masahiro , Tohda Yasuo , Nakashima Hiroko , Tani Keita , Mori Yutaka , Matsumura Eizo
Published: July 2006

New ring transformations of 3,5-dinitro-1-(4-nitrophenyl)-4-pyridone and its homologues with hydroxylamine were found to give 4-nitro-5(2H)-isoxazolone. These results were rationalized by double ring transformations in sequence. The fact that the 4-position of the 4-pyridone behaved as an electrophlic site was the first example in this series of ring transfomations, and was caused by the alpha-effect of the reagent. Some reactions of the isoxazolone were carried out.