bluuebunny/crossref_metadata_2025 huggingface dataset:
The Reaction of Aromatic Nitrile N-Oxides with Tetrahalo-p-benzoquinones
Authors: Shiraishi Shinsaku , Ikeuchi Satoru , Sen\={o} Manabu , Asahara Teruzo
Published: July 2006

Cycloaddition reaction of aromatic nitrile N-oxides, such as benzonitrile N-oxide, 2,4,6-trimethylbenzonitrile N-oxide, and 2,3,5,6-tetramethylbenzonitrile N-oxide, with tetrahalo-p-benzoquinones was studied. The reaction gave 1:1- and/or 2:1-adducts of a nitrile N-oxide and a tetrahalobenzoquinone according to the conditions, especially the mole ratios of each reactant. The 2:1-adducts are formed via 1:1-adducts, each having two stereoisomers. The structures of these adducts were determined to be dioxazole derivatives formed by the addition of nitrile N-oxides to the carbonyl bonds of the tetrahalobenzoquinones.
Cyanamide Derivatives. Part 106. The Preparation of 15N-Labeled Cyanoguanidines
Authors: Omura Akira , Nonaka Tsutomu , Fuchigami Toshio , Ichikawa Eiichi , Odo Keijiro
Published: July 2006

Methods for labeling the chemically non-equivalent nitrogen atoms of cyanoguanidine with 15N were established. 1-Cyanoguanidine-1-15N and 1-cyano-15N-guanidine were prepared, and their labeled positions were also confirmed by mass spectroscopic analysis. 15N FT-NMR spectra of cyanoguanidine enriched with 15N were measured.
Synthesis and Spectral Characteristics of 4H-1-Benzothiopyran-4-ones
Authors: Nakazumi Hiroyuki , Kitao Teijiro
Published: July 2006

The physical properties of 4H-1-benzothiopyran-4-ones (thiochromones) and related compounds were characterized by means of mass, NMR, and UV spectra in order to distinguish thiochromones from 2H-1-benzothiopyran-2-ones (thiocoumarins). In the mass spectra, the fragmentation due to the retro-Diels-Alder reaction directly from the molecular ion is the most useful for differentiation. In the NMR spectra, thiochromones show the characteristic deshielding effect of benzenoid proton in 5-position and in the UV spectra a very strong absorption band in the region 250–270 nm. It was found that in the reaction of S-phenyl 3-oxobutanethioates with PPA, most of these compounds afford thiochromones through rearrangement giving an intermediate (IVa). The effect of the substituent of the S-phenyl 3-oxobutanethioate on the formation of the thiocoumarin was also discussed.
Far Infrared Reflection Spectra and Lattice Vibrations of CsNiCl3 Crystal
Authors: Akiyama Kenji , Morioka Yoshiyuki , Nakagawa Ichiro
Published: July 2006

The frequencies of the transverse (TO) and longitudinal (LO) modes of the infrared active vibrations of the crystal CsNiCl3 were obtained from the polarized far infrared reflection spectra. The polarized Raman spectra were also measured. The calculation of the TO and LO frequencies near the center of the Brillouin zone was made on the basis of a rigid ion model which includes effective ionic charges and interionic repulsive force constants. A set of potential constants and effective ionic charges were determined from the observed values of the TO and LO frequencies and Raman frequencies using the least-squares method. The short-range force constant associated with the nickel ion to the chlorine ion indicates that some amount of covalent character is included in this bond.
Preparation of Nickel(II) Complexes with 2,3-Butanediamines and Their Thermal Octahedral-Square Planar Transformation
Authors: Nishimoto Hideyuki , Yoshikuni Tadatsugu , Uehara Akira , Kyuno Eishin , Tsuchiya Ryokichi
Published: July 2006

The following nickel(II) complexes with meso- or dl-2,3-butanediamine (abbreviated to meso-bn and dl-hn, respectively) were prepared: [Ni(meso-bn)3]X2·2H2O, [Ni(meso-bn)2]X2 and [Ni(H2O)2(dl-bn)2]X2 (X=Cl, Br). It was found from the changes in the absorption spectra and magnetic susceptibilities that [Ni(meso-bn)3]X2·2H2O complexes, when heated to 188 (X=Cl) and to 233 °C (X=Br), respectively, undergo transformations from octahedral to square planar structures with the loss of two moles of lattice water and one mole of coordinated meso-bn. [Ni(H2O)2(dl-bn)2]X2 complexes were similarly found to transform from octahedral to square planar structures at 120 (X=Cl) and at 110 °C (X=Br), respectively with the evolution of two moles of coordinated water. After this transformation, the resulting complexes underwent the inverse transformation from square planar to octahedral structure at 170 °C, without any weight change. The effect of the configurational difference between meso- and dl-hn on the formation of tris and bis(2,3-butanediamine) complexes is also discussed.
Vibrational Spectra of Hydantoin and Its C- and N,N′-Deuterated Compounds
Authors: Saito Yutaka , Machida Katsunosuke
Published: July 2006

Infrared and Raman spectra of hydantoin and its C- and N,N′-deuterated derivatives in the solid state have been recorded. The fundamental frequencies were assigned by referring to isotopic frequency shifts and vibrational spectra of related compounds. Normal coordinate analysis was carried out by using a planar Cs molecular model. A simple Urey-Bradley force field was used for the stretching and the bending coordinates and a valence force field for the out-of-plane deformation and the torsional coordinates. The force constants were refined by the least squares method to reproduce the observed frequencies.
Photo-Induced Friedel-Crafts Acylation of Anthracene with Aroyl Chlorides
Authors: Tamaki Takashi
Published: July 2006

The photo-excitation of anthracene (1) in the presence of benzoyl chloride and its p- or m-substituted compounds (2) gave the corresponding 2- and 9-aroylanthracenes. No isomeric 1-aroylanthracenes (3) were detected. The aroyl chlorides (2) were found to quench the fluorescence of 1. The quenching constants obtained increased with increasing electron-withdrawing ability of the substituents and are in agreement with those independently obtained from the quantum yield determinations. The efficiency of the photoaroylation was dependent on the solvent polarity. The results suggest a plausible photochemical mechanism, which involves a CT complex formed from 1 in the excited singlet state and 2 in the ground state. This complex formation is supported by the positional selectivity exhibited in the product distribution.
Manganese Dioxide Oxidation of Thioureas
Authors: Sharma T C , Sahni N S , Lal Amba
Published: July 2006

Manganese dioxide oxidation of thioureas in chloroform at room temperature gave the corresponding ureas.
TEA CO2 Laser Induced Photoreactions of Ethylene, Chloroethylenes and Chloroethanes
Authors: Nagai Keiichi , Katayama Mikio
Published: July 2006

TEA CO2 laser induced chemical reactions of ethylene, chloroethylenes and chloroethanes have been investigated. Since these compounds have absorptions at wavelengths of 10.6 or 9.6 μm band of the CO2 laser, strong excitation of the molecular vibration gives rise to an infrared photochemical reaction. In chlorine derivatives, the cleavage of the C–Cl bond by the laser irradiation appears to initiate decompositions of these materials. The final products were mainly brought about by molecular elimination of HCl, H2, or Cl2. The present results demonstrate that the CO2 laser induced reactions differ form their thermal reactions.
N,N-Disubstituted 1,3-Dithiolan-2-iminium–TCNQ\ewdot Salts: Effect of the Substituents on the Nitrogen Atom on the Composition and the Electrical Conductivity
Authors: Araki Shingo , Tanaka Toshio
Published: July 2006

Following 10 simple and complex salts of TCNQ\ewdot with N,N-disubstituted 1,3-dithiolan-2-iminium cations; (Remark: Graphics omitted.) (n=1 when R1=R2=n-Pr, n-C6H13, n-C8H17, Ph, and R1=Me and R2=Ph; n=2 when R1= R2=n-Pr, n-Bu, Ph, and R1=Me and R2=Ph), and (Remark: Graphics omitted.) were prepared. Of these, simple salt (Remark: Graphics omitted.) was obtained in two different crystalline forms; unstable violet needles and green plates. All the salts as compacted samples displayed semi-conducting behaviors in the 20–90 °C range. Electrical resistivities of the 1:2 complex salts fell in the range of 5–90 ohm cm at 25 °C, while the simple and 2:3 complex salts showed much large resistivities (the order of 103–109 ohm cm). The measurements of electronic absorption spectra and magnetic susceptibilities indicated that the simple salts in the solid state involve dimeric (TCNQ)22−, except for the green salt of (Remark: Graphics omitted.) which consists of the iminium cation and discrete TCNQ\ewdot radical anion. Electronic spectra of the 1 : 2 and 2 : 3 complex salts also are discussed in comparison with analogous TCNQ\ewdot salts reported so far.
The Formation of Manganese and Cobalt Ferrites by the Air Oxidation of Aqueous Suspensions and Their Properties
Authors: Kiyama Masao
Published: July 2006

Manganese and cobalt ferrites were prepared by the air oxidation of aqueous suspension of Fe(OH)2 and either Mn(OH)2 or Co(OH)2 at 50–80 °C. In alkaline suspensions, all the metal ions are transformed into spinel ferrites, MxFe3−xO4 (M=Mn or Co), by a suitable combination of the oxidation temperature and the concentration of the excess NaOH. Both manganese and cobalt ferrites consist of ferromagnetic particles (ferrite(A)) when x is smaller than 1.3, nonferromagnetic particles (ferrite(B)) when x is larger than 2, and mixtures of the two in the intervening range. The contents of Mn or Co, both in a solid solution of hydroxides, Mx⁄3Fe1−x⁄3(OH)2, and in ferrite, increase with the progress of the formation of the ferrite(A) caused by oxidation. The formation of the ferrite(B) begins when x in the solid solution reaches 2. Each particle in the ferrite(A) is less homogeneous in comparison with that in the ferrite prepared by a solid-state reaction, although with the same composition. The difference in the homogeneity causes the essential difference in magnetic properties.
Ground States of the Square Planar Low-Spin Cobalt(II) Complexes
Authors: Nishida Yuzo , Kida Sigeo
Published: July 2006

In order to investigate the ground state configuration of some square planar cobalt(II) complexes such as Schiff base complexes of the cis-[CoN2O2] type, whose ESR spectra are quite different from those of cobalt(II) phthalocyanine and porphyrins, the spin-orbit matrix based on the four zero-order wave functions, (yz)1, (xz)1,(z2)1, and (xy) were diagonalized on assuming reasonable values for necessary parameters. The result has clearly shown that an unpaired electron is localized in dyz orbital in the ground state for these complexes. ESR spectra of a series of cobalt(II) complexes with N4-macrocyclic ligands were measured and interpreted in terms of the conclusion obtained here.
Structure-taste Relationship of Novel α-l-Aspartyl Dipeptide Sweetners
Authors: Miyoshi Muneji , Nunami Ken-ichi , Sugano Hiroshi , Fujii Toshiyuki
Published: July 2006

A sweetness potency was found in novel α-l-aspartyl dipeptide analogs which were quite stable on heating in an aqueous solution. The insertion of a methylene group into the peptide chain of α-l-aspartyl dipeptide esters mostly decreased the potency of the sweetness. However, the further exchange of the carbonyl and oxygen functions with each other on the ester group of a C-terminal β-alkyl-β-aminopropionic acid was found to increase the sweetness. Thus, N-(α-l-aspartyl)-O-pivaroyl-d-alaninol, N-(α-l-aspartyl)-O-cyclobutylcarbonyl-d-alaninol and N-(α-l-aspartyl)-O-cyclopropylcarbonyl-d-alaninol were all more than 200 times as sucrose.
A Comparative Study of the Photo-induced Berson-Willcott Rearrangement of Methyl 3-Isopropyl-1a,7b-dihydro-1H-cyclopropa[a]naphthalene-1-exo- and 1-endo-acetate
Authors: Kato Masahiko , Tsuji Masakazu , Miwa Toshio
Published: July 2006

The effect of 1-exo- and 1-endo-methoxycarbonylmethyl groups on the course of the photo-induced BersonWillcott rearrangement of methyl 1a,7b-dihydro-1H-cyclopropa[a]naphthalene-1-acetate have been studied. Different reaction rates with the same final products have been observed and are discussed from the view of the stereochemical course of the reaction, which strongly supports the 60°-mechanism, i.e., a slither motion of C-1 with inversion of configuration.
Vinyl Polymerization. 368. Polymerization of Methyl Methacrylate with the System of RNA, Water and Cu(II) Ion
Authors: Imoto Minoru , Nishida Yoshiyuki , Yoshikawa Toshiyuki , Ouchi Tatsuro
Published: July 2006

The radical polymerization of methyl methacrylate (MMA) was carried out with the system of ribonucleic acid (RNA), Cu(II) ion and water. The generation of free radical was found to take place in the water layer where RNA and Cu(II) ion exist. Urea shows a promoting activity. The effects of pH of water medium and temperature on the conversion of MMA were investigated. A reaction mechanism was proposed.
1,3-Dipolar Cycloadditions to Bicyclic Olefins. IV. The Influence of Non-neighboring Double Bonds on the Stereoselectivity in 1,3-Dipolar Cycloadditions to Bicyclo[n.2.2]alkadienes
Authors: Taniguchi Hisaji , Ikeda Toshikazu , Imoto Eiji
Published: July 2006

1,3-Dipoles, such as phenylglyoxylonitrile oxide (1), benzonitrile oxide, and phenyl azide, undergo cycloadditions to the more electron-rich double bond of 2,3-bis(methoxycarbonyl)bicyclo[2.2.2]octa-2,5-diene (5) to afford only endo adducts. The cycloadditions of these 1,3-dipoles to the more electron-rich double bond of 6,7-bis(methoxycarbonyl)bicyclo[3.2.2]nona-6,8-diene (6) give only exo adducts. Benzonitrile-N-phenylimine (4) undergoes cycloadditions to both the more electron-rich and the more electron-poor double bonds of 5 or 6. The reaction of 4 with 5 yields two endo adducts, and the reaction of 4 with 6 gives two exo adducts. However, the cycloaddition of 1 to 5,6-endo,endo-bis(methoxycarbonyl)bicyclo[2.2.2]oct-2-ene affords both the exo- and endo adducts. The reason for the predominant endo cycloadditions toward 5 and exo cycloadditions toward 6 is discussed.
The Study of Thermochemical Hydrogen Preparation. VI. A Hydrogenevolving Step through the H2S–CO Cycle
Authors: Dokiya Masayuki , Fukuda Kenzo , Yokokawa Harumi , Kameyama Tetsuya
Published: July 2006

A two-step decomposition process of hydrogen sulfide was studied. The process is constituted from a hydrogen-evolution step (CO+H2S\oversetca.200°C→H2+COS) and a carbonyl sulfide-decomposition step (COS\oversetca.830°C→CO+1⁄x·Sx. Almost an equilibrium amount of hydrogen could be produced in the first reaction (ca. 40%, 200 °C, 1 atm, CO/H2S=2.2) with a cobalt sulfide or nickel sulfide catalyst. In the second reaction, an almost equilibrium amount of carbonyl sulfide (45%) could also be decomposed into carbon monoxide and elementary sulfur at 830 °C under 1 atm with a sufficient reaction rate and selectivity without using any catalysts. Carbon dioxide was formed as a by-product in the second reaction: however, its yield was only 5% of the carbon monoxide produced. From these results, it may be concluded that this two-step decomposition process of hydrogen sulfide can produce more hydrogen than that produced by the direct decomposition of hydrogen sulfide. In the second reaction, however, the recombination of carbon monoxide with elementary sulfur can not be neglected. Thus, a rapid separation of sulfur from carbon monoxide is required.
Conductance Behavior of Manganese Soap Solutions in 1-Butanol and 3-Methyl-1-butanol
Authors: Varma R P , Singh K , Singh H
Published: July 2006

The specific conductance of manganese soap solutions in 1-butanol and 3-methyl-1-butanol has been measured at temperatures in the range 35–50 °C. Manganese soaps form micellar aggregates and the CMC, which decreases with increase in chain length of the soaps of saturated fatty acids, was found to be independent of the nature of the solvent. Conductance behavior of soaps is given by the equation logλM=A+BlogC where A and B are constants and C is the concentration in mol/dm3. Constant A increases with increase in temperature and chain length of the soap. Constant B is independent of temperature but varies with soap chain. Molecular conductance at infinite dilution, λ∞, dissociation constant, K, activation energy of conductance, ΔEλ, and heat of dissociation, ΔH°, have been evaluated.
The Verification of Three-Dimensional Aromaticity: Tricarbonyliron Complexes of Olefins
Authors: Aihara Jun-ichi
Published: July 2006

Using Mingos’s Hiickel molecular-orbital model, polyolefins were found to be markedly aromatized by the coordination of tricarbonyliron. The Dewar-type resonance energies calculated for the title compounds are consistent with their chemistry.
An Infrared Study of Acid Sites on Silica-Alumina Catalysts Poisoned with Sodium Hydroxide
Authors: Take Jun-ichiro , Ueda Toshiaki , Yoneda Yukio
Published: July 2006

We investigated the effect of NaOH impregnation on the acidic properties (the type, strength, and amount of acid sites) of silica-alumina by means of IR spectroscopy of chemisorbed pyridine. Most acid sites on the unpoisoned catalyst were of the Lewis type. Some Lewis-bound pyridine was retained on the surface even at 400 °C, but the pyridinium ion was eliminated at 300 °C, indicating that the strong acid sites were also of the Lewis type. Impregnated NaOH affected both Lewis and Brønsted sites. An increase in the amount of NaOH resulted in the elimination of the Brønsted acid sites of medium strength, and also in a significant reduction in the number of Lewis acid sites over the whole range of acid strength. Weak Brønsted acid sites showed no marked change in number. When the NaOH-impregnated catalysts were exposed to pyridine, a new IR band appeared at about 1445 cm−1; this band is attributable to pyridine associated with the Na ions on the surface.
Studies of the Metal Complexes of Cyclohexane Derivatives. IV. Copper(II) and Nickel(II) Complexes of 1,2-Cyclohexanediamine Isomers
Authors: Saito Reiko , Kidani Yoshinori
Published: July 2006

Two types of copper(II) complexes, Cu(c-chxn)2X2·nH2O and Cu(t-chxn)2X2·nH2O (X=Cl−, Br−, NO3−, and ClO4−, n=0–2), and three types of nickel(II) complexes, [Ni(c-chxn)2]X2, [Ni(c-chxn)3]X2·nH2O (X=Cl−, Br−, NO3−, and ClO4−, n=0.5–1.5) and [Ni(t-chxn)2(H2O)2]X2 (X=Br− and ClO4−), were synthesized. Here, c-chxn and t-chxn stand for cis- and trans-1,2-cyclohexanediamine respectively. Based upon the analyses of the electronic spectra and magnetic moments, the structures of the copper(II) complexes synthesized were found to be distorted octahedrons. The influence of the steric configurations of the diamine isomers on the structures of the copper(II) complexes is small. The three types of nickel(II) complexes were found to have square planar, octahedral, and distorted octahedral structures respectively. The steric influence of the ligands on the properties of the nickel(II) complexes was also considered.
Diffusion Coefficients of Argon in Aqueous Ethanol and 1,4-Dioxane Solutions and of Methane in Aqueous Ethanol Solutions
Authors: Taira Y\={u}k\={o} , Matsuda Kunio , Nakanishi Koichiro
Published: July 2006

The diffusion coefficients of argon in water-rich regions of aqueous solutions of ethanol and of 1,4-dioxane and those of methane in aqueous solutions of ethanol have been measured by using a diaphragm cell apparatus, designed after Hildebrand et al., for dissolved gases in liquid. The diffusivity of gases was found to show much anomaly which might be ascribed to the structural change of water due to the addition of another solvent. The viscosity reduced diffusion coefficient Dη (D: diffusion coefficient, η: viscosity coefficient) has a maximum value in dilute aqueous solution of both ethanol and 1,4-dioxane.
Electrical and Spectroscopic Investigations of Molecular Layers of Fatty Acids Including Carotene
Authors: Ohnishi Toshihiro , Hatakeyama Masahiro , Yamamoto Naoto , Tsubomura Hiroshi
Published: July 2006

Spectroscopic and electrical studies have been made for the mono- and multi-molecular layers of barium stearate mixed with carotene. The results of the electronic spectra have indicated that the carotene molecules lie parallel to the monolayer plane and are aggregated. The capacitances measured are expressed well as those of parallel plate capacitors. From these results, the structure of the layers containing carotene has been deduced.
Fluorescence Lifetime Measurements of Morin–Metal Ion Complexes
Authors: Sawada Tsuguo , Shibamoto Takeshi , Kamada Hitoshi
Published: July 2006

Fluorescence lifetimes of morin complexes of Be(II), Zn(II), Al(III), Ga(III), In(III), Th(IV), Zr(IV), and Sn(IV) extracted into isopentyl alcohol from the acid solution at various pH values were investigated. The result indicates that the Al(III), Ga(III), and In(III) complexes change their compositions according to the change of pH. More detailed investigations by the use of mole ratio method suggest that Al(III), Ga(III), and In(III) form complexes having two different mole ratios of 1 to 1 and 1 to 2 (metal ion: morin). Fluorescence lifetimes were changed according to the changes of the composition of the complex and the differences of the metal ion.
Five-coordinate Bis(8-aminoquinoline) Nitrosylcobalt Complexes
Authors: Miki Eiichi , Okamura Hiromichi , Mizumachi Kunihiko , Ishimori Tatsujiro
Published: July 2006

[Co(C9H8N2)2NO]X2·nH2O (C9H8N2=8-aminoquinoline; X=Cl, Br, I, NO3, ClO4, and SO4/2; n=0, 1, 1.5, and 2) was isolated by the reaction of nitrogen oxide with a mixture of the corresponding cobalt(II) salt and 8-aminoquinoline in methanol. The IR, UV, and molar conductivity measurements suggest that the geometry of the cation is a tetragonal pyramid with an apical NO−.
Studies of Peptide Antibiotics. XXXVIII. Synthesis of S,S′-Bi([1-l-hemicystine]-gramicidin S), a Dimerized Analog of Gramicidin S
Authors: Sato Kazuki , Ueda Kazuo , Kondo Michio , Aoyagi Haruhiko , Izumiya Nobuo
Published: July 2006

To investigate the importance of the orientation of side chains of amino acid residues in gramicidin S (GS) for the antibacterial activity, a dimerized analog of GS, namely S,S′-bi([1-l-hemicystine]-GS) (13) was synthesized via removal of p-methoxybenzyl group of [1-S-p-methoxybenzyl-l-cysteine]-GS (12) and subsequent oxidation. Compound 12 showed the same antibacterial activity as GS, whereas 13 was inactive. The resemblance of ORD curves of the two analogs to that of GS suggested the similarity of peptide-backbone structure of these three compounds. Strong activity of 12 was explained by similar conformation of 12 to that of GS. To explain the inactivity of 13, a molecular model was proposed; four hydrophilic side chains are located on surface of the molecule, whereas six hydrophobic are burried.
Preparation of Organic Copper(I) Complexes by the Reactions of Methylbis(triphenylphosphine)copper(I) with Nitroalkanes, β-Diketones, and Cyanoalkanes
Authors: Yamamoto Takakazu , Kubota Minoru , Miyashita Akira , Yamamoto Akio
Published: July 2006

Reactions of a methylcopper complex CH3Cu(PPh3)2(diethyl ether)0.5 (PPh3=triphenylphosphine) with three types of active hydrogen compounds HA give the corresponding copper derivatives of active hydrogen compounds formulated as ACu(PPh3)2. Nitroalkanes (nitromethane, nitroethane and 2-nitropropane) form copper complexes bonded through aci-nitro groups. β-Diketone and its analogs such as acetylacetone, diethyl malonate and ethyl acetoacetate react in their enol form to give six-membered O,O′-bonded chelates, whereas cyanoalkanes including acetonitrile, propionitrile, and malononitrile afford organocopper complexes having a direct Cu–C bond.
1,3-Dipolar Cycloadditions of N-(p-Substituted benzylidene) p-Substituted Benzylamine N-Oxides with trans-Bis(p-substituted benzoyl)ethylenes and the Substituent Effects on the Reaction Rates
Authors: Tada Keishi , Yamada Tomoharu , Toda Fujio
Published: July 2006

1,3-Dipolar cycloadditions of N-(p-substituted benzylidene) p-substituted benzylamine N-oxides with trans-bis(p-substituted benzoyl)ethylenes gave the trans- and the cis-2,3-bis(p-substituted phenyl)-4,5-bis(p-substituted benzoyl)isoxazolidines. The configurations of the resulting isoxazolidines were determined by NMR spectra. The formation ratios of the trans- to cis-adducts were determined by liquid chromatography. The second-order rate constants in xylene at 60 °C were obtained by high speed liquid chromatographic analysis. The rates varied with the σ values of the substituents R1 on the N-benzylidene benzylamine N-oxides and R3 on the dibenzoylethylenes, and linear relationships between logk and σ have been established. These results indicate that the HOMO(N-oxide)–LUMO(dibenzoylethylene) interaction predominates. The ρ-values for R1 and R3 were respectively; ρ=−0.41±0.01, ρ=+0.60±0.02.
Study on Solubilization by Electrophoresis and Diffusion
Authors: Ogino Keizo , Abe Masahiko , Takeshita Nobuo
Published: July 2006

The difference in solubilization phenomena exhibited when polar and nonpolar oily materials are solubilized by Sodium dodecyl sulfate (SDS) has been investigated by measuring the electrophoresis, the diffusion, and the viscosity. Based on the assumption that the micelle is spherical the effective specific volume, the effective radius, the ζ-potential and the number of effective charges have been calculated. At the limit of solubilization all four quantities were larger for octanoic acid than for octane. The electrophoretic mobility of the micelle, |UM|, increased when octanoic acid was solubilized, in contrast to a decrease observed in the solubilization of octane.
The Fries Rearrangement of bz-Benzoyloxybenzofuran Derivatives and the Synthesis of the Furo Derivatives of 4-Phenyl-2H-chromen-2-one
Authors: Kawase Yoshiyuki , Yamaguchi Seiji , Aoyama Kumiko , Matsuda Michiyo
Published: July 2006

The Fries rearrangement of 4-, 5-, 6-, and 7-benzoyloxy-2,3-dimethylbenzofurans gave exclusively or mainly the corresponding o-hydroxy ketones, which were converted to the dimethylfuro derivatives of 4-phenyl-2H-chromen-2-one.
The Effect of the Vibrational and Translational Energies of Ionic Reactant on the Reaction C3H4++NH3→C3H3+NH4+
Authors: Honma Kenji , Koyano Inosuke , Tanaka Ikuzo
Published: July 2006

The effect of the internal and translational energies of ionic reactant on the rates of the reactions C3H4++NH3→C3H3+NH4+ has been examined by producing the reactant ions from propyne, allene, and cyclopropene by photoionization at various wavelengths. The translational energy was varied by changing the repeller voltage in the ionization chamber. The cross sections for all the reactions decreased with an increase in the internal energy at all the translational energies studied. The results have been explained in terms of the complex mechanism.
Pressure-Induced Metal-to-Ligand Electron Transfer and the Electrical Conductivity of Some PtIIj-Glyoximes
Authors: Hara Yoji , Nicol Malcolm F
Published: July 2006

Mid-infrared (900–1600 cm−1), visible absorption spectra and electrical resistance of bis(benzil dioximato)platinum(II) [abbreviated as Pt(bz)2], bis(dimethylglyoximato)platinum(II) [Pt(dmg)2], bis(1,2-cyclohexanedione dioximato)platinum(II) [Pt(cd)2], and bis(pyruvaldehyde dioximato)platinum(II) [Pt(pa)2] have been measured at high pressures. A decrease of the C=N frequency by −40.0 cm−1, with reduction of the dπ→π* optical transition intensity by \simeq14%, show that [Pt(bz)2] enhances thermally its dπ→π* electron transfer at high pressures up to 35 kbar. No such changes are observed for [Pt(dmg)2], [Pt(cd)2], and [Pt(pa)2]. This backbonding causes [Pt(bz)2] to release the instability, due to increasing overlapping of the electron clouds around Pt(II) at high pressures, that is the cause of the resistance minimum.
Regeneration to the Native Form of Hen Egg-White Lysozyme from Its Protected Derivatives
Authors: Aimoto Saburo , Shimonishi Yasutsugu
Published: July 2006

The following derivatives of hen egg-white lysozyme were prepared from native hen egg-white lysozyme, 2-chlorobenzyloxycarbonyl-lysozyme, S-(4-methylbenzyl)-reduced-lysozyme, and 2-chlorobenzyloxycarbonyl-S-(4-methylbenzyl)-reduced-lysozyme. Treatment of these derivatives with anhydrous liquid hydrogen fluoride for 90 min at 0 °C yielded fully active lysozyme with recoveries, in order, of 23, 12, and 7.4%. The properties of the lysozyme recovered were identical with those of native hen egg-white lysozyme, and crystals of this material were indistinguishable from those of native enzyme.
A Novel Type of Polycondensation Utilizing Transition Metal-Catalyzed C–C Coupling. I. Preparation of Thermostable Polyphenylene Type Polymers
Authors: Yamamoto Takakazu , Hayashi Yasuhiro , Yamamoto Akio
Published: July 2006

Transition metal compounds including NiCl2(bpy) (bpy=2,2′-bipyridine), NiBr2(PPh3)2 (PPh3=triphenylphosphine), PdCl2(bpy), NiCl2, CoCl2, FeCl2, and FeCl3 catalyze polycondensation of di- and polyhalogenated organic aromatic compounds by dehalogenation with magnesium under mild conditions. Poly(p-phenylene), poly(m-phenylene), poly(oxybiphenylene), and poly(phenylenemethylene) were prepared from p-dihalobenzene, m-dichlorobenzene, bis(p-bromophenyl) ether, and α,p-dichlorotoluene. They have a high degree of polymerization and high thermal stability. Poly(p-phenylene), poly(oxybiphenylene), and poly(phenylenemethylene) have regularly repeated structures as proved by IR spectroscopy and X-ray powder diffraction. Polymerization of polyhalogenated aromatic compounds (1,3,5-trichlorobenzene and hexachlorobiphenyl) in tetrahydrofuran (THF) gave copolymers having aromatic nuclei and THF units. Polymerization of the haloaromatic compounds is considered to proceed through a mechanism in which consecutive cycles of oxidative addition of haloaromatic compounds (R–X) to the transition metal catalyst take place so as to cause alkylation (arylation) by the Grignard reagent formed in the system (R′MgX) and elimination of R–R′ from an active transition metal compound having R and R′ groups.
The Synthesis of Tetrakisdehydrotetraazaannulenes. Tetramethyl[32]-,[40]-, and Tetrabenzo[32]annulene
Authors: Ojima J\={u}ro , Shiroishi Y\={u}ji , Fujiyoshi Masamitsu
Published: July 2006

The conjugate aldehydes, containing terminal acetylenes, were converted to the corresponding conjugated azines 6a–c and 8a–c, respectively. Oxidative couplings of these azines were attempted. The azines 6b, 6c, and 8b afforded the corresponding cyclic dimers 9, 10, and 11, respectively. Examination of 1H NMR spectra indicates that the tetraazaannulenes are atropic.
Structures of Lanthanoid Complexes of Glyceric Acid, Gluconic Acid, and Lactobionic Acid from the Lanthanoid-Induced 1H NMR Shifts: pH Dependence of the Lanthanoid-Substrate Equilibria
Authors: Taga Tooru , Kuroda Yoshihiro , Ohashi Makoto
Published: July 2006

Lanthanoid-induced 1H NMR shifts of glyceric acid, gluconic acid, and lactobionic acid were observed in D2O. Stoichiometric analysis using the shift data at various pH values indicated that the concentration of a 1 : 1 complex between substrates and lanthanoid ions was higher than that of a 2 : 1 complex at a low pH. The structure of an axially symmetric 1 : 1 complex was obtained on the assumption of a predominant pseudo-contact interaction between a europium ion and the ligand nuclei. All the title glycosidic acids were found to chelate the cation with α-carboxy, α-hydroxy, and β-hydroxy oxygens. The relative position of β-hydroxy oxygen is particularly important for the complex formation between β-hydroxy carboxylic acids and metal ions.
Electron Configuration Analysis for Many-System Interactions. Electron Delocalization in Pyracylene, Acepleiadylene, and Dipleiadiene
Authors: Inagaki Satoshi , Hirabayashi Yoshio
Published: July 2006

The method of electron configuration analysis for many-system interactions (ECAMSI) has been developed and applied to the π electronic structures of polycyclic molecules. The HMO-ECAMSI calculations have been carried out on acenaphthylene, pleiadiene, pyracylene, acepleiadylene, and dipleiadiene. Electron delocalization in the naphthalene core predominates in these molecules and remains unchanged from acenaphthylene to dipleiadiene; the central cross-linked π bond is not a small perturbation. There are four electron-delocalizing modes for the cyclic peripheral conjugation in acepleiadylene which give rise to an additional but appreciable delocalization, while the peripheral delocalization in pyracylene and dipleiadiene is almost completely depressed. The substituent effects on the delocalization have been predicted on the basis of the ECAMSI results and on the concept of the continuity-discontinuity of cyclic conjugation which has recently been developed.
Isomerization of Carvomenthene Oxide over Solid Acids and Bases
Authors: Arata Kazushi , Akutagawa Susumu , Tanabe Kozo
Published: July 2006

The reaction of carvomethene oxide (a mixture of cis- and trans-forms) over solid acids and bases gives trans-and cis-1-methyl-3-isopropyl-1-cyclopentanecarbaldehyde (III), carvomenthone (IV), 1(7)-p-menthen-2-ol of trans-(V) and cis-form and carvotanacetol of trans-(VI) and cis-form. A large amount of III was formed together with IV over SiO2–Al2O3, SiO2–TiO2 and zeolite H-F9. LiClO4, H2SO4/SiO2, FeSO4, and solid H3PO4 gave preferentially IV, while TiO2-ZrO2 formed mainly V and VI. With respect to aluminas, carbonyl compounds (III and IV) were predominantly formed over Al2O3D, while allylic alcohols (V and VI) were preferentially given by Al2O3 A and B.
The Oxidative Animation of Tropone and Tropolone
Authors: Kikuchi Katsuo , Maki Yuji , Sato Kazuo
Published: July 2006

The reaction of tropone with aniline, p-toluidine, p-anisidine, and p-chloroaniline in the presence of copper(II) acetate gave 2-arylaminotropones and 2-arylamino-N-aryltroponeimines. However, when o-toluidine and o-anisidine were used, only the corresponding 2-arylaminotropones were obtained. The reaction of tropolone with methylamine, ethylamine, and isopropylamine afforded 3-aminotropolone derivatives, while the reaction with dimethylamine, pyrrolidine, and morpholine gave 3- and 5-aminotropolone derivatives, the latter being minor products.
Catalysis by Phosphine Complexes of Silylruthenium Hydrides of the Addition of Carbon Tetrachloride to 1-Octene
Authors: Matsumoto Hideyuki , Nakano Taichi , Nagai Yoichiro , Kono Hiromichi
Published: July 2006

Phosphine complexes of silylrutheniumhydrides of types [RuH3(SiR3)(PPh3)3] (where R3Si=Et3Si, Me2PhSi, and (MeO)3Si) and [RuH(SiR3)(PPh3)2] (where R3Si=Cl2MeSi and (MeO)3Si) were found to be much more effective catalysts for the addition of carbon tetrachloride to 1-octene than RuCl2(PPh3)3 or RuH2(PPh3)4.
Studies on 5–8 Fused Ring Compounds. III. Hydrogenolysis of 4,4-Dimethyltricyclo[6.3.0.01,7]undecane-2,6-dione
Authors: Umehara Misao , Hishida Shinzaburo , Fujieda Kunimi , Ogura Haruo , Takayanagi Hiroaki
Published: July 2006

Hydrogenolysis of 4,4-dimethyltricyclo[6.3.0.01,7]undecane-2,6-dione with a Pd-C catalyst gave cis-4,4-dimethylbicyclo[6.3.0]undecane-2,6-dione and 8,8-dimethylspiro[4.6]undecane-6,10-dione. The cis isomer has been shown to isomerize almost completely to the trans isomer under acidic and basic conditions.
The Crystal Structure of the B-form of Stearic Acid
Authors: Goto Midori , Asada Eiichi
Published: July 2006

The crystal structure of the B-form of stearic acid has been studied by X-ray diffraction. The structural parameters were refined by the block-diagonal least-squares method, and the final R value was 0.084. In this structure, the bond between the second and third carbon atoms was found to be the gauche conformation, although the other bonds were in the trans conformation usually seen in normal fatty acids.
Infrared Study of Surface Hydroxyl Groups on Zirconium Oxide
Authors: Yamaguchi Tsutomu , Nakano Yasuko , Tanabe Kozo
Published: July 2006

Zirconium oxide has two absorption bands, at 3780 and 3680 cm−1, after several hours’ evacuation at 500 °C. The exchange of deuterium with the surface hydroxyl groups was studied by using D2O, acetone-d6, 2-propanol-d8, and chloroform-d. D2O, acetone-d6, and 2-propanol-d8 could completely exchange the hydrogens of the surface hydroxyl groups at room temperature, while chloroform-d could not exchange them even under saturated vapor pressure at room temperature. Hydroxyls showing 3780 cm−1 band were selectively and irreversibly chlorinated by chloroform-d. After deuteration, two deuteroxyl bands were observed, at 2780 and 2705 cm−1; these were exchanged rapidly with ammonia and slowly with propylene. At room temperature propylene exchanged the hydrogen with the hydroxyls with a 2780 cm−1 band more rapidly than with the hydroxyls with a 2705 cm−1 band. In the adsorption and desorption of 2-propanol, the behavior of the 2780 cm−1 band was also found to be different from that of the 2705 cm−1 band. It was concluded that the 3780 and 3680 cm−1 bands could be assigned to surface hydroxyl groups, the nearest neighbors of which have different configurations, and the hydroxyl group of 3780 cm−1 is more reactive than the hydroxyl group of 3680 cm−1.
Reaction Mechanism of the Photooxidation of the Toluene–NO2–O2–N2 System in the Gas Phase
Authors: Akimoto Hajime , Hoshino Mikio , Inoue Gen , Okuda Michio , Washida Nobuaki
Published: July 2006

Photooxidation of the toluene (34 ppm)–NO2(8–207 ppm)–N2 and/or O2(1 atm) system has been studied in a 67 dm3 reaction chamber. The reaction was initiated by O(3P) atoms formed in the photolysis of NO2. The main products were benzaldehyde, cresols, benzyl nitrate, m-nitrotoluene, 6-nitro-o-cresol, and 2-nitro-p-cresol. Their relative yields were studied as functions of reactant concentrations. The formation mechanisms of the products were proposed on the basis of the reactions of O(3P) and OH radicals with toluene in the presence of NO2 and O2.
Transient Absorption in the Sensitized Photoisomerization of Stilbene
Authors: Sumitani Minoru , Yoshihara Keitaro , Nagakura Saburo
Published: July 2006

The sensitized photoisomerization of stilbene was studied with nanosecond time-resolved absorption spectroscopy at room temperature. In non-viscous solvents (heptane, benzene, and ethanol), the transient spectrum does not depend upon a starting material being either cis- or trans-stilbene. The kinetic analysis of the transient spectrum due to stilbene shows that the observed spectrum consists of the Tn-T1 absorption spectrum of trans-stilbene and that of twisted triplet (phantom triplet) stilbene. The lifetime of the twisted triplet stilbene is determined to be approximately 120 ns. In a viscous solvent (t-butyl alcohol), the transient behavior of triplet stilbene is dependent upon the starting materials being either cis- or trans-stilbene. The contribution of the twisted triplet stilbene to the transient spectrum is larger for the case starting from cis-stilbene than for the case starting from trans-stilbene.
The Enantioface-differentiating (Asymmetric) Hydrogenation of the C=O Double Bond with Modified Raney Nickel. XXX. The Temperature Dependency of the Optical Yield
Authors: Ozaki Hiroshi
Published: July 2006

The effect of the reaction temperature upon the optical yield was studied in the liquid-phase enantioface-differentiating hydrogenation of methyl acetoacetate with various modified Raney nickel catalysts (MRNi) under an atmospheric pressure of hydrogen. The results obtained are as follows: 1) the enantiomer produced in excess in the reactions with (S)-alanine-, (S)-2-aminobutyric acid-, and (S)-valine-MRNi, changed from (S)-(+) to (R)-(−) with the elevation in the reaction temperature (The temperature, T0, at which the direction of the differentiation changed decreased in the order of alanine-, 2-aminobutyric acid-, and valine-MRNi. The origin of T0 is expected to be steric and polar effects that act in opposite directions for the differentiation of the enantioface.), and 2) the temperature dependence of the optical yield with (R,R)-tartaric acid- and (S) -lactic acid-MRNi differed from that with other catalysts. The OH group of the modifying reagent is expected to play an important role in enantioface-differentiation by making a hydrogen bond with the substrate.
Studies of the Yields of 57Fe(II)-species Produced after the EC-decay and of 60Co(II)-species Produced in the (n, γ) Reaction in Cobalt(III) Coordination Compounds
Authors: Sano Hirotoshi , Harada Masayuki , Endo Kazutoyo
Published: July 2006

The yields of 57Fe(II)-species produced after EC-decay were compared with those of 60Co(II)-species produced in the 59Co(n,γ)60Co reaction for twelve cobalt(III) coordination compounds. The results indicate that the radiochemical yield of 60Co(II)-species correlates with the yield of 57Fe(II)-species except in the case of [Co(NH3)6]2(CrO4)3. The anomalously low yield of 57Fe(II)-species in [Co(NH3)6]2(CrO4)3 is ascribed to the reaction of chromate anions with ammine ligands initiated by the nuclear transformation in a solid.
Photo-induced Oxidation of Diethylene Glycol Dimethyl Ether and Analogues with Aqueous Hydrogen Peroxide
Authors: Ogata Yoshiro , Tomizawa Kohtaro , Fujii Kohzo
Published: July 2006

Photo-oxidation of diethylene glycol dimethyl ether (DEDE), ethylene glycol dimethyl ether(EDE) and ethylene glycol monomethyl ether(EME) in the presence of aqueous H2O2 has been studied. DEDE and EDE give photo-oxidation products containing methanol, EME, methoxyacetaldehyde, methoxyacetic acid and methyl formate. EME gives products containing methanol, methoxyacetaldehyde and methyl formate. The oxidation is started by hydrogen atom abstraction by HO. radicals formed by the photolysis of H2O2. A reaction mechanism leading to the products (derived by initial C–O and C–C fissions) is postulated.
Preparation and Properties of Nickel–Phosphine Complexes Coordinated with α,β-Unsaturated Ester
Authors: Ishizu Junichi , Yamamoto Takakazu , Yamamoto Akio
Published: July 2006

Reactions of bis(1,5-cyclooctadiene)nickel, Ni(cod)2, with α,β-unsaturated esters in the presence of tertiary phosphine give a series of nickel-phosphine complexes formulated as Ni(tertiary phosphine)nL(L=alkyl methacrylates, methyl acrylate, or methyl cinnamate; n=2 for P(C6H5)3, P(C2H5)(C6H5)2, P(CH3)2(C6H5), P(C2H5)3, n=1 for P(cyclo-C6H11)3). Elemental analyses, IR and NMR spectra, and chemical properties of the complexes confirm the molecular formula. The olefinic proton signals of methyl acrylate and alkyl methacrylates coordinated to nickel shift to upfield by 2.6–4.9 ppm from those of free olefins in the 1H-NMR spectra, indicating that the α,β-unsaturated esters coordinate to nickel through the double bond. The IR spectra show only small low frequency shifts of the ν(C=O) bands of the α,β-unsaturated esters on complex formation. The reactions of Ni(P-(C6H5)3)2 (ethyl methacrylate) and Ni(P(cyclo-C6H11)3) (ethyl methacrylate) with vinyl acetate at room temperature cause the scission of the C–O bond in vinyl acetate to yield ethylene and nickel acetate.
Molecular Conformations of γ-Aminobutyric Acid and γ-Amino-β-hydroxybutyric Acid in Aqueous Solution
Authors: Tanaka Kaori , Akutsu Hideo , Ozaki Yukihiro , Kyogoku Yoshimasa , Tomita Ken-ichi
Published: July 2006

Proton magnetic resonance and Raman spectra indicate that the backbone of γ-aminobutyric acid is fairly flexible and rotational isomers are almost equally populated in aqueous solution. The population is not much affected by change of pH. On the other hand, in γ-amino-β-Hydroxybutyric acid the trans-trans and gauche-trans conformations of the backbone are equally populated in neutral solution, trans-trans conformation being predominant in non-zwitterionic forms. The conformation in solution is discussed in relation to the structure of these molecules in crystal.
Layered Compounds. LIII. Unique Skeletal Rearrangement of Multilayered [2.2]Paracyclophanes
Authors: Horita Hisanori , Koizumi Yosuke , Otsubo Tetsuo , Sakata Yoshiteru , Misumi Soichi
Published: July 2006

Skeletal rearrangements of multilayered [2.2]paracyclophanes to [2.2]metaparacyclophanes with several Friedel-Crafts acids have been studied. Two types of rearrangements depending on the catalyst were observed. Treatment of triple-layered paracyclophane(8) with AlCl3–HCl gave mainly triple-layered metaparacyclophane(9), which was derived by migration of one of the ethylene bridges attached to the outer benzene rings. Treatment of 8 with mild protonic acids such as SnCl4–HCl, TiCl4–HCl, etc. afforded two kinds of metaparacyclophanes 10 and 11 in high yields, which arose from double migration of the two ethylene bridges attached to the inner benzene ring. Such a double migration of substitutents was also observed in the case of tertamethyl[2.2]paracyclophane and quadruple-layered one. The structures of products were determined by means of NMR spectra, alternative syntheses, and X-ray analyses. The mechanism of the rearrangements is discussed in view of protonation experiment.
Macrocyclic Enzyme Model Systems. Catalytic Activity of Cyclic Peptides Involving Hydrophobic Segments
Authors: Murakami Yukito , Nakano Akio , Matsumoto Kiyoshi , Iwamoto Kiyoshi
Published: July 2006

In order to develop an effective hydrolase model, BCP-1 was synthesized and its kinetic behavior investigated. The corresponding linear hexapeptide was prepared by the solid phase method and subjected to cyclization by the azide method. BCP-1 enhanced the hydrolysis of p-nitrophenyl carboxylates bearing a long alkyl chain. The pH-rate profile for the hydrolysis of p-nitrophenyl hexadecanoate (PNPP) as effected by BCP-1 was not of a bell-shaped type but a sigmoid, from which the kinetic pKa value was estimated as 12.3. The initial reaction rate was found to level off beyond a certain range of substrate concentration (saturation-type kinetics), the kinetic data being analyzed on the basis of Michaelis-Menten scheme. The large hydrophobic binding ability of BCP-1 toward PNPP (Km(app) \simeq10−6M) was attributed to its double-layered bicyclic structure. The Hammett plot for the hydrolysis of substituted phenyl hexadecanoates gave a satisfactory linear correlation. Consequently, the acyl transfer from the bound substrate to the imidazole anion of the histidyl residue of BCP-1 was referred to the rate-determining step. The large negative entropy change for the acyl transfer step seems to indicate that the Michaelis complex does not have a conformation favorable for such acyl transfer process. The catalytic effectiveness (kcat⁄Km(app)) for the BCP-1 catalysis in PNPP hydrolysis is comparable to that for enzymatic hydrolysis.
Topological Properties of Benzenoid Systems. IV. On Aihara’s Resonance Energy
Authors: Gutman Ivan
Published: July 2006

Different mathematical properties of a resonance energy, recently defined by Aihara (This Bulletin, 50, 2010 (1977)), are presented.
Kinetics and Mechanism of the Oxidation of Alcohols by Pyridinium Chlorochromate
Authors: Banerji Kalyan K
Published: July 2006

The kinetics of the oxidation of ten primary alcohols by pyridinium chlorochromate has been studied. The main product of the oxidation is the corresponding aldehyde. The reaction is of first order with respect to the concentration of the alcohol and oxidant. The reaction is catalysed by acid, the catalysed reaction being nearly first order in acidity. The kinetic isotope effect, kH⁄kD is 5.71 at 303 K for ethanol. The reaction does not induce polymerisation of acrylonitrile. The reaction constant ρ* for the uncatalysed and acid-catalysed oxidations have the values −1.93 and −1.75 at 303 K respectively. Probable mechanisms are discussed.
Polarization Dispersion in the Resonance Raman Spectra of EDA Complexes with TCNE and TCNB
Authors: Tahara Masao , Matsuzaki Susumu , Maeda Shiro
Published: July 2006

Synopsis. Polarization dispersion of the νC≡N Raman line of the N,N-dimethylaniline-TCNB complex indicated that the two CT absorption bands are assignable to different acceptor orbitals, in contrast with those of TCNE complexes.