bluuebunny/crossref_metadata_2025_split huggingface dataset:
Episulfones. III. Reductive Cleavage of Episulfones by Complex Metal Hydrides
Authors: Matsumura Shoichi , Nagai Toshikazu , Tokura Niichiro 
Published: July 2006

Abstract
The reduction of cis-stilbene episulfone (I) by such a complex metal hydride as lithium borohydride, sodium borohydride, or lithium aluminum hydride gave dibenzylsulfone (V) selectively as a result of the unusual cleavage of the carbon-carbon single bond. Comparing the difference between lithium aluminum hydride and lithium borohydride or sodium borohydride in various solvent systems, we suggest that particular solvent effects are operating in the present reaction. The reduction of I with lithium aluminum hydride resulted in a low yield (0–10%) of V, while the reduction with lithium borohydride afforded V in a 45% yield. The reduction of styrene episulfone (II) gave no carbon-carbon cleavage product, but it did give a carbon-sulfur fission product, yielding sulfinic acid salt (VIII). The formation of VIII is interesting compared with the reduction of styrene oxide by lithium aluminum hydride. Tetraphenylethylene episulfone (III) produced a carbon-carbon cleavage product, 1, 1, 3, 3-tetraphenyl dimethyl sulfone (XI), in a 68% yield. A reaction mechanism for the reductive cleavage reaction has been proposed on the basis of the above-mentioned results. In addition, we observed that diborane was evolved by the reaction of sulfur dioxide with lithium- or sodium borohydrides.
The Autoxidation of Toluene Catalyzed with Cobalt Monobromide in Acetic Acid
Authors: Sakota Koichiro , Kamiya Yoshio , Ohta Nobuto 
Published: July 2006

Abstract
The kinetics of cobalt-catalyzed autoxidation of toluene have been studied in acetic acid in the presence of sodium bromide. The reaction is found to proceed of apparent zero-order in the concentration of toluene for a long duration and of first-order in its initial concentration and of second-order in cobalt ion concentration. In case of ethylbenzene or cumene the rate of oxidation is of first-order in its concentration. This zero-order dependence is explained as a result of the co-oxidation of toluene and its intermediate reaction product, benzaldehyde. A reaction scheme is proposed, which has been shown to be consistent with experimental data by solving out the rate equations simultaneously with a computer, co-oxidation of toluene and benzaldehyde being taken into consideration.
Concurrent Oxygen Exchange and Racemization Reactions of Diaryl Sulfoxides in Concentrated Sulfuric Acid
Authors: Oae Shigeru , Kunieda Norio 
Published: July 2006

Abstract
When diaryl sulfoxides are dissolved in concentrated sulfuric acid at 0°C, characteristic bluish colored solutions are obtained, from which the starting sulfoxides can be recovered quantitatively upon quenching with a large amount of water. When 18O-labeled and optically active sulfoxides are used, one observes the concurrent oxygen exchange and racemization reactions of the sulfoxides. The kinetic behaviors of these reactions have been studied in detail using various substituted diaryl sulfoxides. The rate of the oxygen exchange was found to be identical to that of the racemization while the rates of the racemization were nicely correlated with the Hammett acidity functions (H0) (Slope=1.07). Meanwhile the polar effect of subsituents on the rates of both oxygen exchange and racemization was found to be very small. From these results possible mechanisms for these reactions have been discussed.
The Structure-Stability Relationship of the Metal Ion Complexes of Unsaturated Compounds. III. The Effects of Polar Substituents on the Silver Ion - Olefin Complexation
Authors: Fueno Takayuki , Kajimoto Okitsugu , Furukawa Junji 
Published: July 2006

Abstract
The equilibrium constants for the formation of silver ion complexes of various vinyl compounds in water were determined at 25°C by the distribution method. It has been found that the equilibrium constants obtained are closely related to the Hammett sigma meta values of the relevant substituents, the reaction constant being ρ=−5.07 with the correlation coefficient r=0.974. The results have been interpreted in terms of the inductive effect of the substituents as the most dominant contribution to the stabilities of these complexes.
The Structure-Stability Relationship of the Metal Ion Complexes of Unsaturated Compounds. IV. Argentation Equilibria of Alkenyl Alkyl Ethers
Authors: Fueno Takayuki , Kajimoto Okitsugu , Okuyama Tadashi , Furukawa Junji 
Published: July 2006

Abstract
The equilibrium constants, K, for the formation of 1 : 1 Ag+ - alkenyl alkyl ether complexes were measured in the temperature range 10 to 30°C by the gas chromatographic method. It has been found (1) that cis isomers have the values of K several times greater than those of the corresponding trans isomers, (2) that the K-value tends to diminish with the increasing degree of β-substitutions, (3) that, in a series of cis ethers, K increases as the β-alkyl substituent becomes bulkier, and (4) that the variation of the alkoxy groups causes little change in the K-value. The difference in the K-values between the cis and trans complexes is found to be ascribable mainly to their difference in the enthalpy changes, ΔH, accompanying the complexation. These trends have been discussed on a thermodynamic ground in comparison with those already noted for olefins.
Low Frequency Bands and Barrier to Internal Rotation in Pentafluoroethane
Authors: Kinumaki Susumu , Kozuka Muneteru 
Published: July 2006

Abstract
The infrared absorption spectra of gaseous and liquid CF3CHF2 were examined in the region from 500 to 60 cm−1. The Raman spectrum of the liquid at room temperature was also photographed. In the gas-phase spectrum, bands were observed at 414, 363, 306, 246, 216 and 82 cm−1. The contour of the medium-intensity band at 82 cm−1 was consistent with that to be expected for torsional oscillation. This frequency would correspond to a triple cosine barrier of 4.4 kcal/mol.
The Polarized Absorption Spectra of Solid Molecular Compounds of Chloranil and Aromatic Amines
Authors: Amano Takako , Kuroda Haruo , Akamatu Hideo 
Published: July 2006

Abstract
The polarized absorption spectra of the single crystal were observed for six molecular compounds which involve chloranil as the electron acceptor and aromatic amines as the electron donor. The molecular compounds of N,N-dimethylaniline, 1-naphthylamine, and N,N-dimethyl-2-naphthylamine have a non-ionic ground state. In these cases, the locations of the charge-transfer bands in the crystal spectra are similar to those of the corresponding bands of the 1 : 1 molecular complexes formed in the solution. The solid molecular compounds of p-phenylenediamine, N,N,N′,N′-tetramethyl-p-phenylenediamine, and diaminodurene can be regarded as ionic crystals composed of the positive ion of the donor and the negative ion of the acceptor. In these cases, the absorption bands associated with the component ions are observed in the crystal spectra, but they are broadened and appreciably shifted to a higher energy as compared with the case of the solution spectra of the ions. The absorption band associated with the charge transfer between ions is observed in the near-infrared region of the crystal spectra of these molecular compounds.
The Reaction between Mercury(II) and Organic Compounds. IV. A Photometric Method for the Determination of Basic Amino Acids Precipitated with a Mercury(II) Perchlorate Precipitant and Some Properties of Their Products
Authors: Kai Fumiaki 
Published: July 2006

Abstract
The particular reactivity of basic amino acids in presence of mercury(II) perchlorate gives white amorphous products (by X-ray powder diffraction). The structures of the products may be considered to be [Arg-Hg]ClO4·Hg(ClO4)2, [His-Hg]ClO4·Hg(ClO4)2 and [Lys-Hg]ClO4·Hg-(C1O4)2 on the bases of elemental analytical data and of infrared patterns showing the absorption bands of νas(Hg–O), ν(Hg–N) and perchlorate ions. The applicability of this peculiar reactivity to the separation and photometric determination of basic amino acids has been studied. The above mentioned products were obtained selectively as a mixture from a mixture of about twenty kinds of amino acids. The isolation of the mixture into each product could be performed satisfactorily by utilizing the different solubilities of the products in 10 n acetic acid containing sodium or potassium chloride (3.3 W/V %), and in an aqueous sodium hydroxide solution. Although the products showed characteristic ultraviolet absorption curves differing from those of the components, there were no absorption maxima in any case. The calibration curves, which followed Beer’s law, could be obtained at any proposed wavelength. By using the calibration curves thus obtained, a very small amount of each basic amino acid could be determined spec-trophotometrically in the 220–250 m/μ region, within detection limits of about 10−5–10−4m. Constant absorbancies could be attained in the pH range of 1.5–10.7 of the sample solutions.
Catalytic Dehydrogenation of Secondary Alcohols with Reduced Copper. VI. The Dehydrogenation of Isopropyl Alcohol (Part III)
Authors: Kawamoto Kazuaki , Nishimura Yoshiharu , Hiraki Teruo 
Published: July 2006

Abstract
In order to determine whether the condensing activity of reduced copper is affected by the mode of preparation of the catalyst, the condensation of isopropyl alcohol to isobutyl methyl ketone, diisobutyl ketone, and isobutylmethylcarbinol was studied with catalysts prepared in different ways. It was found that the copper catalyst obtained by the hydrogen treatment of the oxide prepared from copper nitrate and an excess of sodium hydroxide was the most suitable catalyst for the condensation of isopropyl alcohol to isobutyl methyl ketone and diisobutyl ketone, and that the copper catalyst prepared with potassium carbonate was the most suitable catalyst for the dehydrogenation of isopropyl alcohol to acetone with no side reaction.
Asymmetric Hydrogenation with Modified Raney Nickel. IX
Authors: Izumi Yoshiharu , Tanabe Tadashi , Yajima Shinichi , Imaida Masami 
Published: July 2006

Abstract
The asymmetric hydrogenation catalysts were prepared from the Raney nickel catalyst by modifying it with ls-3,3-dimethyl-2-hydroxybutyric acid and the corresponding amino acid, l-t-leucine, which have most methyl groups at the β-position. The asymmetric activities of the catalysts were measured by the hydrogenation of the methyl acetoacetate to methyl 3-hydroxybutyrate. The asymmetric activity of the catalyst modified with an aqueous solution of ls-3,3-dimethyl-2-hydroxybutyric acid was very low, and the direction of asymmetric activity at pH 5.0 was inverted by the temperature of the modifying solution. However, there was a high asymmetric activity in the catalyst modified with l-t-leucine, and this activity was not so influenced by the temperature of the modifying solution. The aysmmetric activities of catalysts modified with α-hydroxy acids and the corresponding amino acids reported in this paper and the previous papers are compared, and the effect of the bulk of the α-alkyl substituent of the modifying reagent upon the asymmetric activity of the catalyst is discussed.
Stereochemical Studies of Monoterpene Compounds. III. Stereochemistry and Intramolecular Hydrogen Bonding of 1-Hydroxy-p-menth-3-en-2-one and Its Reduction Products
Authors: Suga Takayuki , Shishibori Tsuyoshi , Matsuura Tamon 
Published: July 2006

Abstract
1-Hydroxy-p-menth-3-en-2-one (1) was prepared from α-terpinene by the t-butyl chromate oxidation, trans- and cis-p-Menth-3-ene-1,2-diols (4 and 5), 1-hydroxyisocarvomenthone (2), and 1-hydroxycarvomenthone (3) were also prepared from the compound 1 by lithium aluminum hydride reduction or by hydrogenation. The configurations of these compounds, 1–5, were identified on the basis of chemical evidence, and then the preferred conformation was determined by infrared spectroscopy on the basis of the conception of intramolecular hydrogen bonding. 1 and 2 were found to exist predominantly in the hydrogen-bonded conformations, 1a and 2a, respectively. With respect to 3, the existence of the conformational equilibrium, 3a\ightleftharpoons3b, was demonstrated by the presence of the free and bonded hydroxyl bands. Moreover, 4 and 5 were proved to take the preferred conformations of 4a and 5a respectively.
Studies on Isothiazoles. III. A Novel Ring Closure to Isothiazoles by the Reaction of α-Amino Ketones with Thionyl Chloride or Sulfur Monochloride
Authors: Naito Takayuki , Nakagawa Susumu , Okumura Jun , Takahashi Kiyoshi , Kasai Ken-ichi 
Published: July 2006

Abstract
New compounds, 4-hydroxyisothiazoles, have been prepared by the reaction of α-amino ketones with thionyl chloride or sulfur monochloride, which is a novel procedure for cyclization to an isothiazole ring. Polar solvents, especially dimethylformamide (DMF), were preferable for this cyclization. The reaction hardly proceeded in a nonpolar solvent such as benzene, but was accelerated by an addition of a small amount of DMF.
The Structures and the Reactions of Acetyl- and Benzoylacrylic Acids and Their Esters
Authors: Sugiyama Noboru , Gasha Taketoshi , Kataoka Hiroshi , Kashima Choji 
Published: July 2006

Abstract
The Structures and properties of α,β-unsaturated γ-oxo acid, acetyl- and benzoylacrylic acid, and their esters are studied.
Selective Cleavage of Serine Peptides
Authors: Kaneko Takeo , Takeuchi Ikuko , Inui Toshishige 
Published: July 2006

Abstract
The treatment of N-benzyloxycarbonyl-l-alanyl-l-serine methyl ester (I) with phosgene afforded the corresponding O-chlorocarbonyl derivative (II), which was then cyclized to methyl l-3-(N-benzyloxycarbonyl-l-alanyl)-2-oxo-oxazolidine-4-carboxylate (III) accompanied with N-benzyloxycarbonyl-l-alanyl-3-chloro-l-alanine methyl ester (IV) by refluxing in xylene. By the mild alkaline hydrolysis of III, N-benzyloxycarbonyl-l-alanine and l-2-oxo-oxazolidine-4-carboxylic acid (V) were isolated as a result of the selective cleavage of the peptide bond in which an amino group of the serine residue participated. This method was also applied to three other serine peptides; the same results were obtained.
The Acid-catalyzed Bromination of Aromatic Compounds with Potassium Bromate in Aqueous Acetic Acid
Authors: Furuya Yoshiaki , Morita Atsushi , Urasaki Iwao 
Published: July 2006

Abstract
Bromobenzene is obtained in a 64% yield when an aqueous acetic acid solution containing a catalytic amount of sulfuric acid is slowly added to an aqueous acetic acid solution of benzene and potassium bromate at 60°C. It seems, according to the synthetic data, that the formation of bromobenzene is accelerated by an electron-releasing group. The rate of the consumption of active oxygen has been expressed as follows:
v=k_2[BrO_3^-][C_6H_6]+k_3[BrO_3^-][C_6H_6]^2
Here, both k2 and k3 gave a straight line against −log(CBH+⁄CB), with a slope of ca. −2. The reaction is accelerated by sulfuric acid and does not occur at all in the absence of the acid. The evolution of oxygen gas was not observed during the reaction, but the presence of peroxyacetic acid and/or acetyl peroxide in the reaction mixture was indicated by paper chromatography. A mechanism which involves the rate-determining attack of protonated hypobromous acid and/ or protonated acetyl hypobromite on benzene has been suggested.
On the Viscosity of Liquid Selenium
Authors: Hamada Shuichi , Yoshida Naosato , Shirai Toshiaki 
Published: July 2006

Abstract
The viscosities of liquid selenium and partially-chlorinated liquid selenium were measured in the temperature range from 235°C to 305°C using an Ubbelohde-type tilting viscometer. The “intrinsic” viscosities, η0, were estimated by extrapolating the values of the viscosities, ηθ, of various rates of shear to a zero rate of shear. The “intrinsic” viscosities of the liquid selenium were estimated to be 20.18, 13.46, 9.11, 6.32, 3.67 and 2.30 poise at 235, 245, 255, 265, 285, and 305°C respectively. The viscosities of the chlorinated liquid selenium decreased with an increase in the chlorine content, but they varied discontinuously at a chlorine content of 0.0125% and then decreased linearly. The apparent activation energy for the viscous flow of the liquid selenium was estimated to be 17.9 kcal/mol. The apparent activation energies for the viscous flow of the chlorinated selenium varied discontinuously at a chlorine content of about 0.0125%, as in the case of the viscosity. The average-chain length of the selenium molecules was considered not to be changed, but the radicals at both ends of the linear chain vanish in forming the bonds with chlorine atoms with an increase in the chlorination below a chlorine content of 0.0125%. Therefore, it is concluded that the presence of radicals at the molecular ends would have an influence upon the viscosity and the apparent activation energy for the viscous flow of selenium. The notable large value of the apparent activation energy of such a non-branched polymer as selenium was attributed to the large amount of energy needed to transport the segments into the holes.
Bipolar Ion-Exchange Membranes Prepared from Blends of Graft Copolymers
Authors: Kawabe Hiroshi , Yanagita Masaya 
Published: July 2006

Abstract
Bipolar ion-exchange membranes were prepared from graft copolymers of polyethylene (PE). Powders of styrene-grafted PE (I) and 4-vinylpyridine-grafted PE (II), or powders of ethyl acrylate-grafted PE (III) and II were blended in various proportions and melt-pressed to films. Ion-exchange groups were then introduced by the sulfonation (100%), alkaline hydrolysis (100%), or N-methylation (80–90%) of the blend polymer films. Although, in the titration curves of bipolar membranes, pH regions which apparently resemble the isoelectric point of polyampholytes appeared, no behavior based on the interaction between acidic and basic groups was indicated in the survey of their physico-chemical properties. The dependency of the concentration potential of the membranes (Em), containing one kind of ionized group, on the mole fraction of the group (Fi) is not remarkable. On the other hand, the Em of the membranes containing both positively- and negatively-charged groups is strongly dependent on Fi, because of the additive contribution of the oppositely-charged groups to the potential. The bi-ionic potential of the membrane, EK–Li, was found to be a function of Em⁄|E0|(|E0| is the absolute value of the concentration potential for ideal permselective membranes) in the cases of both I-II and II-III.
The Anodic Reaction of Acetic Acid in the Presence of Enanthaldehyde, Enanthaldehyde Diethyl Acetal, and 2-Octanone
Authors: Takeda Akira , Wada Satosi , Torii Sigeru , Matsui Yuji 
Published: July 2006

Abstract
The anodic methylation of enanthaldehyde, enanthaldehyde diethyl acetal, and 2-octanone was attempted by electrolyzing a mixture of acetic acid, ethanol (or tetrahydrofuran and/or acetone), water, and potassium hydroxide. The major products from the electrolysis of enanthaldehyde consisted of 2-octanone, 1-heptanol, 3-methyl-2-octanone, and enanthaldehyde diethyl acetal. Similar products were isolated from the reaction mixture of enanthaldehyde diethyl acetal. The anodic methylation of 2-octanone gave 3-methyl-2-octanone as a major product. Possible mechanisms of the formation of these ketones were discussed.
The Rotatory Dispersion and Stereochemistry of Organic Compounds. XV. Nitrophenyl Glycosides
Authors: Tsuzuki Yojiro , Koyama Motoo , Aoki Kazuyuki , Kato Tatsuo , Tanabe Koko 
Published: July 2006

Abstract
It has been reported that some ortho-nitrophenyl glycosides exhibit anomalous optical rotation (Montgomery et al., J. Am. Chem. Soc., 64, 690 (1942)). To investigate this anomalous effect of the ortho-nitro group the authors have observed the RD spectra on twenty-five derivatives of o-nitrophenyl, p-nitrophenyl and phenyl glycosides. Every o-nitrophenyl derivative (I, IV, VII, XI, XIV, XVII and XX) exhibited a positive Cotton effect near 340 mμ. Furthermore, in order to inquire into this anomaly the authors have observed the CD and UV spectra of these compounds. It follows that the o-nitro group is twisted from the benzene ring plane, and that the o-nitrophenyl group itself becomes an optical active chromophore, so that the Cotton effects near 340 mμ are caused by the n→π* transition of the nitro group. Therefore, the anomaly of o-nitrophenyl glycosides in the [α]D values is concluded to be affected by the strong Cotton effect near 340 mμ.
The Synthesis of Methylacetylene by the Pyrolysis of Propylene. IV. The Pyrolysis of Allyl Chloride
Authors: Kunichika Sango , Sakakibara Yasumasa , Taniuchi Mamoru 
Published: July 2006

Abstract
Allyl chloride has been pyrolyzed in a flow system over a wide range of conditions (temperature, 800–1200°C; contact time, 0.665×10−3–78.9×10−3 sec; concentration, 4.0–13.5 mol%; pressure, atmospheric pressure) to find suitable conditions for producing methylacetylene and allene. In addition, a study on the mechanism of pyrolysis of allyl chloride at high temperatures (800–1200°C) has been made. A total yield of allene and methylacetylene of 14 mol per 100 mol of allyl chloride pyrolyzed was obtained under suitable conditions. By means of the zero conversion method, hydrogen, propylene, allene, diallyl, 1,3-cyclohexadiene, and benzene have been found to be the main reaction products in the early stage of the pyrolysis, while methane, acetylene, ethylene, methylacetylene, butene-1, and butadiene have been found to be the side reaction products. The over-all activation energy of decomposition was 39.4 kcal/mol for an A factor of 108.7 sec−1. On the basis of the observed results, a free-radical mechanism has been proposed for the main reactions and the principal side reactions. It was further concluded that the pyrolysis was a radical decomposition initiated by the reaction C3H5Cl→C3H5·+Cl and that the over-all mechanism in the early stage of the pyrolysis was represented essentially by the reaction 2C3H5Cl→C3H5·+\dotC3H4Cl+HCl.
Alkoxysilanes. II. Preparation of Tributoxysiloxychlorosilanes, Silanols, and Their Polymeric Substances
Authors: Abe Yoshimoto , Kijima Ichiro 
Published: July 2006

Abstract
Tributoxysiloxychlorosilanes [(BuO)3SiO]xSiCl4−x(Bu=t: x=1,2; Bu=s: x=1,2,3 or 4) were prepared by the reaction of silicon tetrachloride with tributoxysilanol in the presence of pyridine. The hydrolysis of these compounds led to the formation of tributoxysiloxysilanols [(BuO)3SiO]xSi(OH)4−x (Bu=t: x=2; Bu=s: x=2 or 3). Tri-t-butoxysiloxysilanetriol was obtained from the corresponding trichlorosilane under mild hydrolytic conditions by using aniline as an hydrogen-chloride acceptor. On the other hand, the hydrolysis of the trichlorosilane with excess water in the presence of pyridine gave a resinous product. The fractional precipitation of this product gave a white powder soluble in such organic solvents as benzene, n-hexane, ether, and carbon tetrachloride; the powder had a molecular weight between 2500 and 4300. This resin turned into glassy solids upon being heated at 200 or 300°C under reduced pressure; these solids had molecular weights between 5500 and 12500. The possible structures for these polymeric substances were discussed on the basis of the results of the elemental analysis, the IR spectra, and the gas chromatography of volatile substances produced in the course of polymerization.