bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Traces of Constituents with Schiff Bases. III. Extraction-Spectrophotometric Determination of Nickel with Salicylidene-o-aminophenol
Authors: Ishii Hajime , Einaga Hisahiko 
Published: July 2006

Abstract
A method was established for the spectrophotometric determination of microgram amounts of nickel after the extraction of nickel(II) as a salicylidene-o-aminophenol (SAP) complex from an alkaline aqueous solution into chloroform. Nickel(II) reacts with SAP to form a complex which can be extracted into organic solvents such as benzene, chloroform, methyl isobutyl ketone, etc., in the presence of ammonium ions. The extraction of nickel was almost quantitative, and a maximum and constant absorbance was obtained in the pH range from 8.5 to 9.8. The complex extracted was very stable and had an absorption maximum at 418 mμ. The composition of the complex was confirmed to be 1 to 1 (metal to ligand). A linear relationship was maintained between the concentration of nickel and the absorbance. The molar extinction coefficient and the sensitivity for log(I0⁄I)=0.001 at 418 mμ were 17000 and 3.5×10−3 μg Ni/cm2, respectively. Several ions such as cobalt(II), copper(I and II), chromium(III), lead(II), manganese-(II) and citrate interfered with the determination.
Spectrophotometric Study of Solution Equilibria between Ammonia and Copper(II) and Nickel(II) Chelates of Aminopolycarboxylic Acids
Authors: Kodama Mutsuo , Miyamoto Katsumi 
Published: July 2006

Abstract
The addition of ammonia produces a remarkable change in the visible absorption spectra of copper(II)- and nickel(II)-aminopolycarboxylate chelates. This can be ascribed to the formation of a mixed ligand chelate involving ammonia and the aminopolycarboxylate anion. On the basis of the change in the absorbance of copper(II)- and nickel(II)-aminopolycarboxylate chelates, the solution equilibria between ammonia and these aminopolycarboxylate chelates were investigated. Copper(II) and nickel(II) chelates of ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)-ethylenediamine-N,N′,N′-triacetic acid (EDTA-OH), ethylenediaminetetrapropionic acid (EDTP), cyclohexanediaminetetraacetic acid (CyDTA), and diethylenetriaminepentaacetic acid (DTPA) were found to form mixed ligand chelates with a composition of M(NH3)Z2−n. From the intercept of the linear relation between log(AY−A)⁄(A−AM) and log[NH3]f, the equilibrium constant, KNH3, defined as KNH3=[M(NH3)Z2−n]⁄[MZ2−n]·[NH3]f, was determined.
Epoxidation of Eight- and Twelve-Membered Cyclic Olefins with Hydrogen Peroxide in the Presence of Metal Oxide Catalysts
Authors: Itakura Jo , Tanaka Hisao , Ito Hiroo 
Published: July 2006

Abstract
The oxidation of eight- and twelve-membered cyclic olefins by H2O2 was carried out in various alcohols using some metal oxides as catalysts. In contrast to the case of cyclohexene and norbornene, which can be hydroxylated, the oxidation of 1,5,9-cyclododecatriene, cyclododecene, 1,3- and 1,5-cyclooctadiene and cyclooctene with H2O2 in the presence of selenium dioxide resulted in selective formation of the corresponding monoepoxides. The following rate equation was obtained with cyclooctene (COE) in isopropanol:
−d[H2O2]⁄dt=k3′[SeO2][H2O2]+k3″[SeO2][H2O2][COE].
A Study of the Solvent Effect in the Copolymerization of N-Phenylethylenimine with β-Propiolactone
Authors: Kagiya Tsutomu , Kondo Tomizo , Fukui Kenichi 
Published: July 2006

Abstract
The effect of the solvent on the copolymerization of N-phenylethylenimine with β-propiolactone has been studied quantitatively. The copolymerization rates for the various solvents used increase in the order: diethyl ether &gt; toluene &lt; carbon tetrachloride &lt; methyl acetate &lt; N,N-dimethylacetamide &lt; anisole &lt; dioxane &lt; acetone &lt; ethylene dichloride &lt; acetonitrile &lt; acetophenone &lt; nitrobenzene &lt; dimethyl sulfoxide &lt; nitroethane. The rates in solvents with high dielectric constants are much larger than those in solvents with low dielectric constants. However, in the case of solvents with similar dielectric constants, the rates decrease with an increase in the nucleophilicity of the solvent; moreover, the dependency of the copolymerization rate on the nucleophilicity of the solvents is much larger in the solvents with high dielectric constants than in those with low dielectric constants. The rate of the consumption of N-phenylethylenimine is markedly affected by the nucleophilicity of the solvents in solvents with high dielectric constants, but it is little affected in solvents with low dielectric constants. Although there is no effect of the nucleophilicity of the solvents on the consumption rate of β-propiolactone, the rate of the consumption of β-propiolactone varies with the electrophilicity of the solvent in solvents with high dielectric constants. On the other hand, the β-propiolactone content in the copolymer increases in proportion to the nucleophilicity of the solvents with high dielectric constants, whereas the β-propiolactone content in solvents with low dielectric constants is almost constant regardless of the electric nature of the solvents.
Effect of the Binary Solvent System on the Copolymerization of N-Phenylethylenimine with β-Propiolactone
Authors: Kagiya Tsutomu , Kondo Tomizo , Fukui Kenichi 
Published: July 2006

Abstract
The effect of the binary solvent system on the copolymerization of N-phenylethylenimine with β-propiolactone has been studied quantitatively. The copolymerization was carried out in three kinds of binary solvent systems, each consisting of components with similar dielectric constants (ε) and with very different nucleophilicities: (1) the nitrobenzene - N,N-dimethylacetamide system, ε\fallingdotseq36, (2) the ethylene dichlorice - tetrahydrofuran system, ε\fallingdotseq10, (3) the toluene-anisole system, ε\fallingdotseq3. In the binary solvent system with the highest dielectric constant, the copolymerization rate decreased with an increase in the content of the nucleophilic solvent. In the nitrobenzene -N,N-dimethylacetamide system, the copolymerization rate markedly decreased upon the addition of a small amount of N,N-dimethylacetamide in nitrobenzene. On the other hand, in the ethylene dichloride - tetrahydrofuran binary solvent system, with a lower dielectric constant than the nitrobenzene and N,N-dimethylacetamide system, the rates decreased in proportion to the tetrahydrofuran content. The β-propiolactone content in the copolymer increased with the amount of the larger nucleophilic solvents, and the dependency of the copolymer composition on the nucleophilicity of the solvents was much larger in the binary solvents with high dielectric constants than in the binary solvents with low dielectric constants. In the toluene - anisole system, which has a very low dielectric constant, the copolymerization rate and the composition of the copolymer were almost constant, independent of the composition of the solvents.
The Addition Reactions of Dialkyl Phosphites to Polyfluorocyclobutenes
Authors: Ueda Teruo , Inukai Kan , Muramatsu Hiroshige 
Published: July 2006

Abstract
The radiation-induced addition reactions of dialkyl phosphites to polyfluorocyclobutenes, such as perfluoro-, 1,2-dichlorotetrafluoro-, 1-chloro-2,3,3,4,4-pentafluoro-, 1,3,3,4,4-pentafluoro- and 1-chloro-3,3,4,4-tetrafluorocyclobutenes were carried out. In general, the corresponding dehydrohalogenated 1 : 1 adducts, polyfluorocyclobutenylphosphonates, were obtained as the main products instead of the expected 1 : 1 adducts. The direction of attack of the phosphonyl radical on the unsymmetrical double bond and reaction mechanism were discussed.
A New σ-Bonded Complex Formation between 2-Vinylpyridine and Palladium(II) or Platinum(II) Chloride
Authors: Kasahara Akira , Tanaka Keiko , Izumi Taeko 
Published: July 2006

Abstract
Sodium tetrachloropalladate(II) reacts with 2-vinylpyridine in methanol, ethanol, or isopropyl alcohol, to give, respectively, di-μ-chloro-bis[2-methoxy-2-(α-pyridyl)ethyl]dipalladium(II), di-μ-chloro-bis[2-ethoxy-2-(α-pyridyl)-ethyl]dipalladium(II), and di-μ-chloro-bis[2-isopropoxy-2-(α-pyridyl)ethyl]-dipalladium(II). The reaction of potassium tetrachloroplatinate(II) with 2-vinylpyridine in methanol or ethanol affords, respectively, di-μ-chloro-bis[2-methoxy-2-(α-pyridyl)ethyl]diplatinum(II) and di-μ-chloro-bis[2-ethoxy-2-(α-pyridyl)ethyl]diplatinum(II). The structures of these complexes containing the covalent metal - carbon bonding have been confirmed by a study of their absorptions and of the NMR spectra.
The Synthesis of Cyclic α-Amino Acids. III. The Synthesis of Methyl (+)- and (−)-3-Amino-3-C-carboxy-3-deoxypentopyranosides
Authors: Yanagisawa Hiroaki , Kinoshita Mitsuhiro , Umezawa Sumio 
Published: July 2006

Abstract
Cyclization of D′-methoxy-diglycolaldehyde, prepared by periodate cleavage of methyl β-l-arabinopyranoside, with ethyl nitroacetate gave a mixture of stereoisomers of cyclic α-nitro ester, i.e. methyl (+)-3-deoxy-3-C-ethoxycarbonyl-3-nitropentopyranoside. Catalytic reduction of the cyclic α-nitro ester afforded an isomeric mixture of cyclic α-amino esters, from which, on column chromatography, there could be isolated four diastereoisomers of methyl (+)-3-amino-3-deoxy-3-C-ethoxycarbonylpentopyranoside. Hydrolysis of each diastereoisomer gave the corresponding cyclic (+)-α-amino acid having a skeleton of pentopyranoside. The stereochemistry of the isomeric amino acids was studied by NMR spectroscopy and chemical degradation. On the other hand, three enantiomeric cyclic (−)-α-amino acids were also obtained from methyl β-d-xylopyranoside by the analogous route as that from methyl β-l-arabinopyranoside.
The Alkaline Hydrolysis of Halophenols
Authors: Oae Shigeru , Furukawa Naomichi , Asari Takashi 
Published: July 2006

Abstract
The mechanism of both the alkaline fusion and the alkaline hydrolysis of halophenols has been investigated. In case of alkaline fusion, the product identified is resorcinol, the formation of which has been found to proceed through the benzyne intermediate. While the alkaline hydrolysis of halophenols gives different ratio of dihydroxyphenol and phenol by changing the mole ratio of halophenol to alkali, by utilizing 14C tracer experiment and substituted halophenol, the mechanism of the formation of both products has been revealed to proceed by way of the direct substitution of halide with hydroxide. Copper compounds are found to be effective in this reaction.
The Yield of Hydrogen Atoms in the Vapor Phase Radiolysis of Ammonia
Authors: Nishikawa Masaru , Kuroda Kazufumi , Matsuura Niro 
Published: July 2006

Abstract
γ-Radiolysis of NH3+C3H8 mixtures was investigated at 22±1°C and total pressure ∼50cmHg. From the observed yield of hydrogen, H atom yield of ammonia radiolysis of GH=5.1–5.8 was obtained after subtraction of contribution from the propane fraction. The value is significantly lower than that determined from the study of NH3+D2 and NH3+N2H4 systems, and also that from the study of NH3+C3H8 system reported previously. A variety of possibilities is discussed with respect to the cause of the disagreement. The effect of addition of N2O or SF6, which acts as an electron scavenger, was also studied. The yield of hydrogen from NH3+C3H8 mixtures decreased appreciably, and ΔG(H2) in the absence and presence of electron scavengers was related to the change in the neutralization process.
The Electronic Spectra and the Intermolecular Interaction of Würster’s Ions in Crystals
Authors: Tanaka Jiro , Mizuno Masagi 
Published: July 2006

Abstract
The electronic spectra and the intermolecular interaction of Würster’s radical have been studied for the dimer state and for the crystalline states. The polarization properties of the excited states have been investigated in detail, and the longest wavelength absorption band of the dimer has been established as having a charge-transfer character. The strength of the charge-transfer band and the shift of the monomer band in the dimer or in the crystalline states are shown to be intimately correlated with the strength of the intermolecular interactions between the stacked radicals. A theoretical analysis of the excited state of the dimer and the crystals is presented; the results are in good agreement with the experimental findings.
Solution Properties of Poly-m-chlorostyrene
Authors: Matsumura Kimiyoshi 
Published: July 2006

Abstract
The solution properties of poly-m-chlorostyrene in toluene and butanone were measured by the light-scattering and viscosity methods. The dependencies of the second virial coefficients, the end-to-end distances, and the intrinsic viscosities on the molecular weights were not very different from those of the other polystyrene derivatives. It was made clear that the unperturbed dimension of poly-m-chlorostyrene was larger than that of poly-p-chlorostyrene, and similar to that of poly-o-chlorostyrene. The relationships between poly-m-chlorostyrene and solvents (toluene and butanone) were similar to those between polystyrene and poly-o-chlorostyrene and the solvents, but the reverse of that between poly-p-chlorostyrene and the latter; that is, compared with butanone, toluene was a “good” solvent for poly-m-chlorostyrene.
Synthetic Hydrogen-containing Ultramarine Phases
Authors: Kubo Yasushi , Yamaguchi Goro 
Published: July 2006

Abstract
Hydrogen was analyzed on synthetic sulfur-containing sodalite-type sodium aluminosilicates. Specimens synthesized from the NaAlSiO4-Na2S system in a H2 or N2 atomsphere or in a N2-S2 atmosphere contained hydrogens which were introduced by ion-exchange during water-washing. Specimens synthesized from the same system in H2S-containing atmospheres also contained hydrogens introduced from the synthetic atmosphere. The latter specimens had the formula: Na8Al6-Si6O24S·xH2S·yS, which was characterized by a constant number of sodium ions (eight per unit cell), whereas the former contained variable numbers of sodium ions according to the duration of water-washing. A difference in correlation between the sulfur content and the lattice constant was observed between these two series of specimens, indicating different manners of existence of the hydrogen.
Polarographic Reduction of Cobalt(II) in Acetonitrile in the Presence of Acetate Ions
Authors: Itabashi Eiki , Ikeda Shigero 
Published: July 2006

Abstract
The effect of the nature and the concentration of the supporting electrolyte on the polarographic reduction of cobalt(II) acetate in acetonitrile has been investigated. An acetonitrile solution of cobalt(II) acetate yields a two-step and a three-step reduction wave in 0.05m LiClO4 and in 0.05m NaClO4 solution, respectively. The same solution gives ill-defined reduction waves in the presence of quaternary ammonium perchlorates, such as (CH3)4NClO4, (C2H5)4NClO4, or (n-C4H9)4NClO4. The Co(CH3CN)n2+, Co(OAc)+, and Co(OAc)3−species are present in a solution containing alkali metal perchlorate electrolyte. Co(OAc)+ and Co(OAc)3− are the predominant species in a quaternary ammonium perchlorate solution. The reduction potential becomes more negative with increase in the number of acetate ions coordinated to cobalt(II). The reduction potential of cobalt(II) acetate becomes less negative upon the addition of alkali metal perchlorate to the quaternary ammonium perchlorate supporting electrolyte. This effect is caused by the dissociation reaction of cobalt(II) acetate, in which an acetate ligand is transferred to the alkali metal ion.
The Kinetic Studies of the Acid-catalyzed Etherification of the Tautomers of p-Nitrosophenol and p-Benzoquinoneoxime with Ethanol in Dioxane
Authors: Furuya Yoshiaki , Urasaki Iwao , Itoho Kazuo , Takashima Akiyoshi 
Published: July 2006

Abstract
The rates of the acid-catalyzed reversible etherification of the allelotrope of p-nitrosophenol and p-benzoquinoneoxime with ethanol in dioxane-forming p-nitrosophenetole have been measured by ultraviolet spectrophotometry. The rate of the forward reaction was expressed as the sum of the second- and the third-orders over a fairly large concentration region of the allelotrope and of ethanol. The plots of the logarithm of the apparent forward second-order rate constant against −log(CBH+⁄CB) gave a straight line with a slope of −0.95. A probable mechanism involving the rate-determining formation of a σ-complex by the nucleophilic attack of the hydroxyl O-atom of ethanol on the α-carbon of the hydroxyl group of protonated p-nitrosophenol, and also the rate-determining deprotonation from the oxime group of the σ-complex by the allelotrope of p-nitrosophenol, was postulated.
Macro Chelate Rings. I. Synthesis of 2,7-Dimethyl-4,5-bis-(salicylideneaminomethyl)acridone as a Quadridentate Chelating Agent and Its Metal Complexes
Authors: Okawa Hisashi , Yoshino Tamotsu 
Published: July 2006

Abstract
2,7-Dimethyl-4,5-bis(salicylideneaminomethyl)acridone, which may form a quadridentate metal complex involving a ten-membered chelate ring, was synthesized by a sequence of steps and characterized. A monomeric cobalt(II) complex of the ligand was isolated and examined.
The Basicities of Substituted Diphenyl Sulfoxides
Authors: Oae Shigeru , Sakai Kazuo , Kunieda Norio 
Published: July 2006

Abstract
The basicities of nine meta- and para-substituted diphenyl sulfoxides have been determined spectrophotometrically in sulfuric acid media. The pKBH+ values thus obtained indicate that these sulfoxides possess rather weak basicities (pKBH+; −3.67–−5.74). and these pKBH+ values gave a good correlation with Brown-Okamoto’s σ+ values, (ρ=−2.00), instead of σ-values. These observations seem to suggest a considerable conjugative interaction between phenyl groups and sulfoxide group of these diphenyl sulfoxides.
Synthetic Studies of Sesamol Derivatives. XI. Synthesis of 5,6-Methylenedioxy-2-isopropenylbenzo[b]furan
Authors: Fukui Kenji , Nakayama Mitsuru , Tanaka Sachihiko 
Published: July 2006

Abstract
5,6-Methylenedioxy-2-isopropenylbenzo[b]furan, an analogue of the naturally-occurring 5,6-dimethoxy compound, has been synthesized by the dehydration of the corresponding 2-(1’-hydroxy)isopropyl derivative, which was obtained from 2-hydroxy-4,5-methylenedioxybenz-aldehyde. By the catalytic hydrogenation of the benzofuran, its 2-isopropyl derivative and its 2-isopropyl-2,3-dihydrofurano-compound were prepared. The NMR spectra of these compounds have been compared.
A New Synthesis of Tephrosic Acid
Authors: Fukui Kenji , Nakayama Mitsuru , Harano Teruo 
Published: July 2006

Abstract
2′-Carboethoxymethoxy-4′,5′-dimethoxy-7-hydroxyisoflavone was prepared from 7-benzyloxy-4′,5′-dimethoxy-2′-hydroxyisoflavone via the corresponding 2′-carboethoxymethoxyisoflavone. The hydrolysis of the 7-hydroxyisoflavone with dilute alkali gave tephrosic acid (2,4-dihydroxyphenyl 2-carboxymethoxy-4,5-dimethoxybenzyl ketone) in a good yield.
Ring Expansion of Bicyclic gem-Dihalo- and Monohalocyclopropanes
Authors: Ando Teiichi , Hosaka Hirokazu , Yamanaka Hiroki , Funasaka Wataru 
Published: July 2006

Abstract
Some bicyclic gem-dichlorocyclopropanes (Ia through Id) and gem-chlorofluorocyclopropanes (IIa through IId) were prepared by the addition of dichloro- and chlorofluorocarbene, respectively, to the appropriate cyclic olefins. The reduction of these dihalocyclopropanes with tri-n-butyltin hydride gave the corresponding monochloro- (IIIa through IIId) or monofluorocyclopropanes (IVa through IVd) in fairly good yields. When treated with an excess of hot quinoline, the endo-chloro isomers of IIa, IIb, IId, IIIa, IIIb, and IIId were converted to their ring expansion products, whereas their exo-chloro isomers were recovered unchanged. In contrast, the exo-chloro isomers of IIe and IIIc decomposed more readily than their endo-chloro isomers under similar conditions. These results were discussed on the concept of a concerted disrotatory process.
1,3-O-Benzylidene-l-sorbose
Authors: Maeda Takashi , Kimoto Mitsuru , Wakahara Shigeru , Tokuyama Kanji 
Published: July 2006

Abstract
It has been proposed that 1,3-O-benzylidene-l-sorbose (III) exists as an equilibrium mixture of a pyranose form (IIIp), a keto-form (IIIk) and a furanose form (IIIf) in solutions. The acetylation of III in pyridine afforded the acetates of IIIf; one of them (IV) is in a keto-form (IVk) in a crystalline state, and at a low temperature, while the acetates of IIIf and IIIp at higher temperatures. When a pyridine solution of III was allowed to stand for some time before acetylation, the yield of the acetate of IIIp increased. The recrystallization of III usually gave crystals of IIIf, however, while the addition of petroleum ether to the concentrated pyridine solution of III afforded a powder which was consisted mainly of IIIp. These results suggest that III exists as IIIf in a crystalline state and as an equilibrium mixture of IIIf, IIIk, and IIIp in solution; the existence of this equilibrium was also confirmed by proton magnetic resonance spectroscopy.
The Nucleophilic Substitution Reactions of 2-Aminotropone Derivatives
Authors: Toda Takashi , Ryu Shôji , Nozoe Tetsuo 
Published: July 2006

Abstract
The nucleophilic substitution reactions of 2-aminotropone (I), 2-methylaminotropone (II), 2-dimethylaminotropone (III), and 2-troponyl trimethylammonium iodide (IV), and their alkyl derivatives were investigated. It was found that the properties of I and II are similar to those of tropolones. On the other hand, those of III are analogous to those of tropolone methyl ethers, while those of IV are, rather, comparable to those of 2-halotropones or tropolone tosylates.
The Mechanism of ESR Relaxation in Peroxylamine Disulfonate Ion ·ON(SO3)22−
Authors: Fujiwara Shizuo , Sakioka Kayoko 
Published: July 2006

Abstract
The mechanism of ESR relaxation in ·ON(SO3)22− is discussed. As the line width in an aqueous solution is plotted against the concentration, it is almost concentration independent in the range lower than 7×10−3 mol/l, but the dependence increases in the higher range. Powles and Moseley showed that the anisotropy of the g-value contributes to the line width in the lower concentration range, but the line width in the higher-concentration range, which is investigated in the present investigation, can not be accounted for by the g-tensor anisotropy. Hence, it is supposed that electron spin exchange or nuclear quadrupole interaction contributes in the higher-concentration range. The latter can, however, be eliminated by the line width measurement in a deuterium measurement in a deuterium oxide solution, and so it may be concluded that electron spin exchange is the main contribution to the line width in the higher-concentration range. This is in accordance with the proposal of Jones. Furthermore, we could show that, by calculation of the line shape for Bloch’s equation, including exchange interactions, the exchange frequency of 5.4×107 sec−1 can give a line fitting the observed line shape for the 7.8×10−2 mol/l solution. This result can be taken as another evidence showing that the electron spin exchange is the main source of the line width in the higher-concentration range.