bluuebunny/crossref_metadata_2025_split huggingface dataset:
Imidazole Catalyses in Aqueous Systems. III. Formation of the Catalyst-Substrate Complex in the Hydrolysis of a Phenyl Ester Catalyzed by a Naphthylimidazole Derivative
Authors: Kunitake Toyoki , Shinkai Seiji , Aso Chuji 
Published: July 2006

Abstract
Catalytic hydrolysis of p-acetoxybenzoic acid by 1-[4(5)-imidazolyl]-4-aminomethylnaphthalene was carried out at 30°C in aqueous systems using a pH-stat. The catalytic rate leveled off at high substrate concentrations and increased remarkably at high pH. The data indicated that both the neutral catalytic species (AmIm) and the monoprotonated catalytic species (Am+Im) acted as enzyme-like catalysts, the catalytic rate conforming to the Michaelis-Menten kinetics, although their catalytic efficiencies were quite different: Km (dissociation constant of the catalyst-substrate complex)=0.011m and k3 (pseudo-intramolecular rate constant of the product-formation)=0.19 min−1 for AmIm, and Km=0.041m and k3=0.036 min−1 for Am+Im. The binding function was attributed to hydrophobic interaction, on the ground that Km was smaller for AmIm than for Am+Im and that an increase in the ionic strength of the medium caused rate enhancement. The hydrolysate showed an inhibitory action. The wide variation of the catalytic efficiency between AmIm and Am+Im may be related to the structural difference of the Michaelis complexes. 1-Aminomethylnaphthalene similarly catalyzed the hydrolysis and showed a substrate binding phenomenon, though the saturation phenomenon was much less pronounced as compared with the imidazole catalyst.
Formation of 4-Hydroxycarbostyrils in the Reaction of Carbon Suboxide with Aromatic Amines
Authors: Omori Akira , Sonoda Noboru , Tsutsumi Shigeru 
Published: July 2006

Abstract
The reactions of carbon suboxide with aromatic amines were found to give various 4-hydroxycarbostyril derivatives. The reaction between aniline and carbon suboxide usually gives malonanilide. However, it was found that the reaction of aniline with carbon suboxide in ether in the presence of aluminum chloride produced phenylcarbamoylacetic acid in a good yield and that cyclization to 4-hydroxycarbostyril occurred when the solvent was replaced by benzene before the decomposition of the reaction mixture with water. The solvent effect on the formation of 4-hydroxycarbostyrils and the possible reaction mechanism were discussed.
Oxidation by Transition Metal Complexes. I. Oxidation of Styrene and Triphenylphosphine Catalyzed by O2-Ir Complex
Authors: Takao Kiyotomi , Fujiwara Yuzo , Imanaka Toshinobu , Teranishi Shiichiro 
Published: July 2006

Abstract
In order to investigate the oxidation reaction which is catalyzed by transition metal complexes in a homogeneous system under mild conditions, the oxidation reactions of styrene and triphenylphosphine catalyzed by various iridium complexes have been studied. The Vaska complex (IrX(CO)(PPh3)2) and the biphosphine chelate complex have been found to be effective as oxidation catalyst. It was found that the SnCl3 ligand which has a strong trans effect promotes the oxidation of styrene. For the sake of comparison with the iridium compounds, oxidation with palladium salts was also studied.
The Preparation and Reaction of Disubstituted Aminophosphonium Bromide. Reaction of Triphenylphosphine Dibromide with Secondary Amines
Authors: Fukui Kiyoshi , Sudo Rokuro 
Published: July 2006

Abstract
Disubstituted aminotriphenylphosphonium bromides were obtained in excellent yields from the reaction of triphenylphosphine dibromide and the secondary amines using simple procedures. This method has an advantage in the preparation of cyclic aminophosphonium salts, such as those of morpholine or piperidine. The treatment of the disubstituted aminophosphonium salt with bases resulted in dehydrohalogenation, followed by a Hofmann-like decomposition, and gave imine and triphenylphosphine.
Studies of Peptide Antibiotics. XVI. Analogs of Gramicidin S Containing β-Alanine in Place of l-Proline
Authors: Matsuura Shuji , Waki Michinori , Makisumi Satoru , Izumiya Nobuo 
Published: July 2006

Abstract
5,5′-β-alanine-gramicidin S having a larger ring size by two methylene groups than that of gramicidin S was synthesized to investigate the contribution of the ring size of gramicidin S to antibacterial activity. Cyclization of a protected linear decapeptide active ester in pyridine gave the protected 5,5′-β-alanine-gramicidin S in a good yield. The product obtained after the cyclization of a protected linear pentapeptide active ester consisted of the protected 5-β-alanine-cyclosemi and 5,5′-β-alanine-gramicidin S. Pure compounds were obtained by column chromatographic separation of Sephadex LH-20. Hydrogenolysis of these protected cyclic peptides in the presence of hydrogen chloride afforded crystalline hydrochlorides of cyclic deca- and pentapeptide. These hydrochlorides exhibited no antibacterial activity against any of the microorganisms tested. Optical rotatory dispersion measurements of these peptides were also carried out.
Studies of Peptide Antibiotics. XVII. Analogs of Gramicidin S Containing Glycine or Alanine in Place of Leucine
Authors: Abe Okitoshi , Izumiya Nobuo 
Published: July 2006

Abstract
In order to investigate the contribution to antibacterial activity of the leucine residues at 3- and 3′-position in gramicidin S, 3,3′-glycine- and 3,3′-l-alanine-gramicidin S (XII-G and XII-A) were prepared and tested for antibacterial properties. A crude product obtained after cyclization of a linear pentapeptide active ester consisted of a protected monomer and a dimer. The pure protected dimer was obtained by a Sephadex LH-20 column from the crude product. Hydrogenolysis of the pure protected dimer afforded the crystalline hydrochloride of XII-G or XII-A. It was found that XII-G showed no activity in any of the microorganisms tested, whereas XII-A exhibited substantial activity though weaker than that of gramicidin S.
Studies on the Formation of Deoxy Sugars by Detosyloxylation with Lithium Aluminum Hydride
Authors: Umezawa Sumio , Tsuchiya Tsutomu , Hineno Hirokuni 
Published: July 2006

Abstract
The reduction of a number of tosylated, mesylated, sometimes further-benzoylated derivatives of methyl 4,6-O-benzylidene-α-d-glucopyranoside (I) with lithium aluminum hydride in tetra-hydrofuran has been investigated; it has thus been found that methyl 4,6-O-benzylidene-2,3-di-O-tosyl-α-d-glucopyranoside (II) gave methyl 4,6-O-benzylidene-3-deoxy-α-d-ribo-hexopyranoside (III, major), methyl 4,6-O-benzylidene-2-deoxy-α-d-arabino-hexopyranoside (IV, minor), and methyl 4,6-O-benzylidene-2-deoxy-α-d-ribo-hexopyranoside (V, minor) as deoxy derivatives through two kinds of monotosyl derivatives (VIII and X), and that methyl 2-O-benzoyl-4,6-O-benzylidene-3-O-tosyl-ribo-d-glucopyranoside (VII) and methyl 3-O-benzoyl-4,6-O-benzylidene-2-O-tosyl-α-d-glucopyranoside (IX) gave VIII and X respectively, as intermediates. 2-O-Methyl-3-O-tosyl (XI) and 2-deoxy-3-O-tosyl derivatives (XIII) gave detosylated derivatives, (XII) and (IV) respectively. These and other results suggest, for detosyloxylation, a mechanism through the formation of an alkoxy-aluminum hydride.
Kinetics of Alkaline Hydrolysis of Esters. III. Acyl Acetals
Authors: Sharma R C , Sharma M M 
Published: July 2006

Abstract
The kinetics of the alkaline hydrolysis of some acyl acetals (liquid and solid) was studied in 90 parts (wt/wt) aqueous ethanol medium. Steric and inductive effects were found to play an important role. A straight line relationship was observed between the rate constants for the alkaline hydrolysis of benzylidene-, and m- and p-nitrobenzylidene diacetates and Hammett’s substitution constant, σ. In the case of n-butylidene and benzylidene diacetates the theory of mass transfer accompanied by fast pseudo first-order reaction was employed for the determination of rate constants in an aqueous medium.
Studies of the Chemiluminescence of Several Xanthene Dyes. V. Blue Emission from an Excited State of a Reaction Product
Authors: Kamiya Isao , Kato Sadao 
Published: July 2006

Abstract
We have found that the chemiluminescence emission of several xanthene dyes with hydrogen peroxide is comprised of two emission components; one is a greenish-yellow emission whose spectral distribution is similar to that of the fluorescence of the dye, and the other is a blue emission similar to the fluorescence band which appears during the course of the reaction. Summarizing the results, we can conclude that the chemical formation of an excited species from the oxidation of a dye, and an energy-transfer process from the species to an unoxidized dye, are likely to be the mechanism for the luminescent reaction. Certain dyes, uranin, eosin Y, eosin R, erythrosin B, 2′,7′-dichlorofluorescein, mercurochrome, rhodamine B, rhodamine 6G, and rhodamine S, showed similar characteristic chemiluminescence emissions, whereas phloxine, rose bengale, 4-nitrofluorescein, 4,5,6,7-tetrachlorofluorescein, sulfonfluorescein, and pyronine G did not chemiluminesce under comparable conditions.
The Anodic Oxidation of a Propionate-Propionic Acid Solution in the Presence of Several Organic Compounds
Authors: Kunugi Akira , Shimizu Toshiyuki , Nagaura Shigeo 
Published: July 2006

Abstract
The anodic oxidation of the propionate anion in aqueous solutions of propionic acid at a platinum electrode has been studied in the presence of several organic compounds in order to demonstrate the formation of both propionoxy and ethyl radicals as the reaction intermediates. One of the following organic compounds was added to each solution: two vinyl monomers (acrylic acid and acrylamide), two alkylbenzenes (toluene and cumene), and two aliphatic alcohols (methanol and isopropanol). The electrooxidation of sodium propionate in the presence of acrylamide resulted in polymerization, which was confirmed to be initiated by the ethyl radical. Acrylic acid, unlike acrylamide, gave no polymers. In this case, both the current efficiency for the formation of carbon dioxide and the yield ratio of ethylene to carbon dioxide were always less than those observed in the absence of acrylic acid. While the addition of alcohols gave no definite results, the addition of toluene or cumene resulted in an appreciable decrease in the yield ratio of ethylene to carbon dioxide, but affecting neither the ratio of ethane to carbon dioxide nor the current efficiency for the carbon-dioxide evolution. These results indicate that the anodic oxidation of the propionate anion proceeds through the consecutive formation of propionoxy and ethyl radicals as the reaction intermediates.
The Crystal Structure of 1-Ethyl-2-methylquinolinium Iodide, [(C12H14N)+·I−]
Authors: Sakanoue Seiki , Kai Yasushi , Yasuoka Noritake , Kasai Nobutami , Kakudo Masao 
Published: July 2006

Abstract
The crystal structure of an organic charge-transfer complex, 1-ethyl-2-methylquinolinium iodide, [(C12H14N)+·I−], has been determined by means of three-dimensional X-ray data (MoKα). The crystals are monoclinic, space group P21/c, and have four formula units in a unit cell with the dimensions of a=7.187±0.002, b=15.914±0.002, c=10.331±0.002 Å, and β=94.67±0.01°. The structure is built up from an iodide anion and a planar 1-ethyl-2-methylquinolinium cation, which lie roughly on a plane. The cations are stacked approximately parallel to the a-plane, forming an endless column along the a axis; the interplanar spacings of these cations are alternately 3.4 and 3.6 Å. The iodide anions are located in the spaces between these columns and the ethyl groups of the cations. The closest distance between an iodide anion and the carbon atoms of a 1-ethyl-2-methylquinolinium ring is 3.93 Å.
Lattice Vibrations of Potassium Oxalate Monohydrate and the Bound State of Water of Crystallization
Authors: Fukushima Kunio 
Published: July 2006

Abstract
A normal coordinate treatment of the potassium oxalate monohydrate crystal as a whole was carried out. On the basis of the results of the calculation, the nature of the lattice vibrations and the bound state of the water of crystallization were discussed.
The Radiolysis and Photolysis of Methanolic Solutions of Eosin. II. The Photo-Debromination of Eosin in an Alkaline Solution
Authors: Kimura Kazuie , Miwa Takuji , Imamura Masashi 
Published: July 2006

Abstract
Semireduced eosin was found to undergo photo-debromination and was identified with a precursor in the photo-debromination of eosin in alkaline methanolic solutions. Semireduced eosin was prepared by the γ-irradiation of an eosin solution. The photolysis of semireduced eosin was investigated by the use of continuous and flash light. From the absorption spectral change and a study of the decay, the mechanism of the photo-debromination was proposed. The debromination process of the photo-excited semireduced eosin was explained satisfactorily by assuming the transient formation of the debrominated-eosin σ-radical as an intermediate. In addition, we found an electron-transfer reaction from semireduced debrominated eosin to eosin, which results in the formation of semireduced eosin and debrominated eosin in the dark. A general conclusion as to the photo-dehalogenation of xanthene dyes is also given.
The Chemical Behavior of Low Valence Sulfur Compounds. II. Thin-layer Chromatographic Separation and Photometric Determination of Low Valence Sulfur Compounds
Authors: Naito Kunishige , Takei Shinsuke , Okabe Taijiro 
Published: July 2006

Abstract
The quantitative determination of some low valence sulfur compounds, especially low polythionates, which appeared as intermediate products in the oxidation of elemental sulfur with compressed oxygen in aqueous ammonia was investigated by means of thin-layer chromatography and colorimetry with methylene blue to establish the mechanism of the oxidation of elemental sulfur. Thiosulfate and some low polythionates could be resolved clearly by thin-layer chromatography using silica gel as an absorbent. A suitable solvent for the development was a mixed solution of ethyl alcohol, n-butyl alcohol, aqueous ammonia, ammonium acetate and distilled water. The amount of sulfur in the developed spot of the thin-layer chromatogram was determined photometrically with precision of 10 to 20% using methylene blue as a color reagent. Sulfate, sulfite and thiosulfate could not be developed effectively by this method.
Activity Measurements in Orthosilicate and Metasilicate Solid Solutions. II. MgSiO3-FeSiO3 at 1154, 1204, and 1250°C
Authors: Kitayama Kenzo 
Published: July 2006

Abstract
The activity-composition relation in the pyroxene solid solution, MgSiO3–FeSiO3, is determined by the quenching method in the atmosphere of a gas mixture of CO2 and H2 at 1154, 1204, and 1250°C. A non-ideality is found in the solution at these temperatures, and it increases with a decrease in the temperature. The standard free energy values of the formation of ferrosilite, FeSiO3, from metallic iron, silica, and oxygen are −42.5±0.3, −41.7±0.2, and −41.3±0.2 kcal per mole of FeSiO3 at 1154, 1204, and 1250°C respectively. Using the data by Darken and Gurry, the standard free energies of the formation of ferrosilite from wüstite and silica are obtained as −1.8±0.3, −1.5±0.2, and −1.8±0.2 kcal per mole of FeSiO3 at 1154, 1204, 1250°C respectively.
The Kinetics of the Aminolysis of Phenyl Phenoxyacetates with Benzylamine in Dioxane
Authors: Furuya Yoshiaki , Itoho Kazuo 
Published: July 2006

Abstract
The rates of the reactions of p- and m-substituted phenyl phenoxyacetates with benzylamine in dioxane, thus forming N-benzylphenoxyacetamide and the corresponding phenols, were followed by the non-aqueous titration of benzylamine. The reaction satisfied the following general equation:
ν={k_2’+k_3’[Amine]}[Amine][Ester]+{k_3”+k_4[Amine]}[Amine][Ester]^2.
The reaction was a neucleophilic substitution, and the Hammett plots gave straight lines with positive ρ values. A marked enhancement in the conductivity of the reaction mixtures in 50% dioxane was observed, it increasing with the reaction time. A probable mechanism was presented which involves an ion pair of the quaternary ammonium salt type somewhat similar to that discussed in a previous paper (Y. Furuya, S. Goto, K. Itoho, I. Urasaki and A. Morita, Tetrahedron, 24, 2367 (1968)).
Studies on Interactions of Isocyanides with Transition Metal Complexes. IV. Dicarbonyl(isocyanide)-π-cyclopentadienylacylmolybdenum
Authors: Yamamoto Yasuhiro , Yamazaki Hiroshi 
Published: July 2006

Abstract
Isocyanides were treated with π-C5H5Mo(CO)3R (R=CH3, CH2Ph) in benzene at room temperature to give π-C5H5Mo (CO)2 (isocyanide)COR (A), which exist as a trans-isomer in the solid state and as a mixture of trans- and cis-isomers in solutions, based on the NMR spectra. The structures of the compounds (A) are discussed on the basis of the spectroscopic studies. Studies on trans to cis isomerization were also carried out kinetically.
Umwandlung von Aldehyden in 2-monosubstituierte Aziridine. Reduktion von α-Chlor, Brom- und Sulfonyloxynitilen mit Lithiumaluminiumhydrid
Authors: Ichimura Kunihiro , Ohta Masaki 
Published: July 2006

Abstract
The reductive cyclization of α-chloro, bromo- and sulfonyloxycarbonitriles are described. α-Chlorocarbonitriles were reduced by lithium aluminum hydride to afford aziridines in sufficient yields. The Walden inversion was found to take place in the cource of the reductive cyclization of S-α-chloroisocapronitrile. We have found the two-step conversion of aldehydes to 2-mono-substituted aziridines which consists of treating aldehydes with benzenesulfonyl chloride and alkali cyanide to form α-benzenesulfonyloxycarbonitriles which are reduced by lithium aluminum hydride to the corresponding aziridines. The reduction of α-bromocarbonitriles with the hydride yielded prim. amines together with the aziridines.
Laser-induced Chemical Reactions. III. The Decomposition of Metal Salts of Carboxylic Acid and Selective Decomposition
Authors: Taki Ko , Kim Pil Hyon , Namba Susumu 
Published: July 2006

Abstract
Various copper metal salts of organic acid were decomposed by laser heating and conventional heating methods. The product distributions were reasonably explained in terms of the expected reaction of the decarboxylated intermediates. Generally the yield percentage of products is higher in laser decomposition than in thermal decomposition. However, in maleate and fumarate the product distribution is quite different in thermal and laser decompositions. The main product is ethylene in the thermal decomposition, but acetylene in the laser decomposition. This difference may be the result of the heating rate. Since rapid heating and quenching are characteristic of laser heating, the formation of acetylene may be brought about by the simultaneous decarboxylation of two carboxyl groups, while the formation of ethylene may be brought about by successive decarboxylation. Selective decomposition by laser heating will also be discussed in binary systems, such as maleate and ethylene.
Substituent Effects on the NMR Chemical Shifts of Aromatic Side Chain Protons. I. The Effects of meta-Substituents
Authors: Yamada Hiroaki , Tsuno Yuho , Yukawa Yasuhide 
Published: July 2006

Abstract
The Hammett type treatment of the chemical shift of substituted aromatic side chain protons has not always been successful. The failure might be ascribed to the neglect of magnetic longrange effects. When the corrections were made both for the ring current diminution due to the contribution of polar resonance structure of the introduced substituent and for the substituent magnetic anisotropy effect, an excellent equation was obtained to relate, the chemical shifts of meta-substituted aromatic side chain protons to the Hammett’s constants.
The Insertion Reactions of Olefins into Metal-Ethyl Bonds in the Vanadium Compounds-Ethyl Aluminum Ziegler Catalyst System. A Proposed Mechanism for the Syndiotactic Polymerization of α-Olefin
Authors: Suzuki Toshimitsu , Takegami Yoshinobu 
Published: July 2006

Abstract
In order to clarify the mechanism of the syndiotactic polymerization of olefin, the insertion reaction of several olefins into metal-ethyl bonds in VCl4-AlEtnCl3−n, VOCl3-AlEtnCl3−n, and V(AA)3-AlEtnCl3−n systems were studied. Cyclohexene was easily inserted into metal-ethyl bonds in these catalysts to give a metal-ethylcyclohexyl bond at −70°C. Pentene-1 and 4-methylpentene-1 gave (Remark: Graphics omitted.) (I) and (Remark: Graphics omitted.) (II). At −70°C with VCl4-AlEt2Cl, where the syndiotactic polymerization of propylene proceeds, four times as much (II) as (I) was obtained. However, at 0°C or in the VCl4-AlEt3 catalyst system, the amount of (I) exceeded the amount of (II). With the VOCl3-AlEtnCl3−n or the V(AA)3-AlEt3Cl3−n system, the selectivity for the formation of metal-alkyl (II) was decreased. The above results lead to the conclusion that, in the course of syndiotactic polymerization, the secondary metal-alkyl bond (II) was an intermediate of the polymerization. By means of this mechanism every experimental result reported can be explained without difficulty.
Oxidative Ring-contraction of Several 1,5-Benzodiazepines with Light
Authors: Matsumoto Masakatsu , Matsumura Yoichi , Iio Akira , Yonezawa Teijiro 
Published: July 2006

Abstract
2,4-dimethyl- (I-a), 2-methyl-4-phenyl- (I-b), and 2,4-diphenyl-1,5-benzodiazepine (I-c) were irradiated with a high-pressure mercury arc under an oxygen atmosphere in benzene and in acetic acid. In all cases oxidative ring-contraction products, 2-acylquinoxalines (II), were obtained. It was found that there was a solvent effect in these reactions ; e.g., in benzene the diazepine (II-d) leads to 2-benzoyl-3-methylquinoxaline (II-d), while in acetic acid it leads to 2-acetyl-3-phenyl-quinoxaline (II-b).
Reactions of Diazoketones in the Presence of Metal Chelates. III. Reactions with Carbonyl Compounds
Authors: Takebayashi Matsuji , Ibata Toshikazu , Ueda Kozaburo 
Published: July 2006

Abstract
The reaction of α-diazoacetophenone with carbonyl compounds such as benzaldehyde, acetophenone and p-phenylacetophenone, has been studied in the presence of bis(acetylacetonato) copper (II). The reaction gave the corresponding tetrahydrofurans and dioxolanes accompanied by some by-products derived from benzoylcarbene. The mechanism of the reaction has been discussed in terms of an intermediate with a structure of betaine type, produced by the reaction of a ketocarbene-metal chelate complex with carbonyl compounds.
Studies of Diazosulfides. II. The Dissociation of trans- and cis-Diazosulfides and the Isolation of cis-Diaryldiazosulfides
Authors: Yamada Takashi 
Published: July 2006

Abstract
The reaction of trans- and cis-N-aryl-S-triphenylmethyldiazosulfides (I) with β-naphthol in alkaline ethanol was investigated. It was found that the dissociation of I occurs not only with the cis isomers, but also with the trans isomers, even in the dark. The kinetic study suggested that the trans-diazosulfides can dissociate not only through the cis form, but also directly, contrary to Zwet and Kooyman’s suggestion. The dissociation of the trans isomer of diaryldiazosulfides (II) was also discussed analogously. Further, by a preparation at −78°C several cis-diaryldiazosulfldes were isolated which had never before been isolated. The rate constant of the isomerization of cis-N-(p-cyanophenyl)-S-(p-toly)diazosulfide (IIf) was 2.55×10−3 sec−1 (at 0°C, in ethanol) ; this value is much larger than that for cis-I.