bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxidation of Alcohols with t-Butyl Chromate. IV. The Course of the Formation of the Ester
Authors: Suga Takayuki , Matsuura Tamon
Published: July 2006

The results obtained in the preceding papers (Parts I–III) of this series showed that, on oxidation with t-butyl chromate, the primary alcohol without a π-electron system on the carbon α to the hydroxymethyl group yields the corresponding ester in a comparable yield, together with the aldehyde and the acid, and also that the cyclic α-glycol with two secondary hydroxyl groups affords the corresponding cyclic ester, along with the glycol fission product. Chemical examination and infrared spectroscopic study have now proved that the course of the formation of these esters does not follow the direct esterification of the alcohol with the acid formed from it by oxidation, but rather involves the formation of a hemiacetal intermediate between the original alcohol and the aldehyde produced from the alcohol, and the subsequent oxidation of the hemiacetal. The oxidation of alcohols with t-butyl chromate has also been discussed generally on the basis of the results of our previous papers and of the present work.
The Effect of the pH Value on the Crystallization of Strontium Sulfate in the Presence of Triphosphate
Authors: Miura Masaji , Naono Hiromitu , Hara Mitunori
Published: July 2006

The crystallization of strontium sulfate has been conductometrically investigated in the presence of triphosphate under various pH values of the solution. The amount of triphosphate adsorbed on the crystal surface of strontium sulfate has been estimated as a function of the pH of the solution. The action of triphosphate in stabilizing the supersaturated solution of strontium sulfate and the amount of triphosphate adsorbed on the crystal surface depend remarkably on the pH of the solution; further, the two are closely correlated with each other. It has been concluded from these facts that the adsorption of triphosphate plays an important role in the stabilization of the supersaturated solution of strontium sulfate.
The Effects of Polyamines on the Melting of Polyriboinosinic Acid Plus Polyribocytidylic Acid Complex in Solution
Authors: Matsuo Kimiko , Tsuboi Masamichi
Published: July 2006

The thermal transition profile (melting profile) of the double-helical complex of polyriboinosinic acid plus polyribocytidylic acid, poly(I+C), into random coils in solution has been examined by the observation of the ultraviolet absorbance at 248 mμ of the solution. The effects of Na+, Mg2+, NH4+, CH3NH3+(CH2)nNH3+ (where n=2, 3, 4, 5, 6, and 8), spermidine, spermine, actinomycin D, and poly-l-lysine upon the melting profile have been observed. Among the diamines examined, that with n=3 has been found to have the maximum effect. Poly-l-lysine has been found to form a complex with poly(I+C) in the solution with a stoichiometric mole ratio of NH2 : P=0.5 : 1.
Kinetic Studies of the Solution Polymerization of Trioxane Catalyzed by BF3·O(C2H5)2. IV. The Change in the Formaldehyde Concentration during Polymerization
Authors: Miki Tetsuro , Higashimura Toshinobu , Okamura Seizo
Published: July 2006

In the solution polymerization of trioxane catalyzed by BF3·O(C2H5)2 and boron fluoride, the dependence of the yield of CH2O produced in the induction period on the polymerization conditions has been studied at 30°C. In the case of the BF3·O(C2H5)2 catalyst, the formation of CH2O has been recognized in n-hexane just after the addition of the catalyst while no induction period of the polymerization was seen. In polar solvents, both the formation of CH2O and the polymerization were retarded as the water concentration increased. In these systems the concentration of the CH2O formed changed with time, and no equilibrium or stationary concentration was recognized. In the case of the boron fluoride catalyst, an increase in the water concentration remarkably increased the induction period, also. For either catalyst the induction period was not decreased by the addition of CH2O to the polymerization system in advance of the catalyst addition. Therefore, it has been deduced that, in the polymerization system catalyzed by BF3·O(C2H5)2, the polymerization and depolymerization reaction took place simultaneously and that the induction period was caused by water, which inhibits the formation of high polymers.
The Synthesis of Some Peptides Related to the Active Site of Enzymes
Authors: Hayakawa Tadao , Harada Kaoru , Fox Sidney W
Published: July 2006

The sequences, α-aspartyl-l-serylglycine and α-glutamyl-l-serylglycine, appear in the “active site” of many esteratic enzymes. The free tripeptides were synthesized in this study. In order to avoid difficulties encountered in more conventional synthetic routes, N-carbobenzoxy-l-aspartyl (β-benzyl ester)-O-benzyl-l-serylglycine dibenzyl ester and N-carbobenzoxy-l-glutamyl (γ-benzyl ester)-O-benzyl-l-serylglycine dibenzyl ester were synthesized. These protected peptides were converted to the free tripeptides upon hydrogenolysis, which removed all of the four protecting groups simultaneously. Several derivatives of these tripeptides were also synthesized.
The Spectrophotometric Determination of Iron(III) with Methylthymol Blue
Authors: Tonosaki Kôichi
Published: July 2006

The reaction between iron(III) and methylthymol blue has been studied spectrophotometrically in an attempt to establish the optimum conditions for determining small amounts of iron. Depending on the acidities of a solution, iron(III) reacts with methylthymol blue to form one of two complexes. The 1-to-1 complex, which has its maximum absorbance in the acidity range from 0.07 to 1.00 m with respect to perchloric acid, has an absorption maximum at about 580 mμ against a reagent blank. The 1-to-2 (metal-reagent ratio) complex, which has its maximum absorbance in the pH range from 4.5 to 5.5, has an absorption maximum at about 520 mμ against a reagent blank. With either complex, Beer’s law is obeyed over the range from 5 to 50 μg. of iron(III) in 25 ml. of complex. The apparent molar extinction coefficients of the two complexes at their absorption maxima were calculated to be 15000 and 14000 respectively (the former, at 0.08 m HClO; the latter, at pH 5). According to Sandell’s notation, the sensitivities of the reactions are 0.004 μg. of iron(III) per cm2 at 580 mμ and 0.005 μg. of iron(III) per cm2 at 520 mμ respectively. The effect of diverse ions was examined with a solution containing iron(III) and 25 cations.
The Liquid-Liquid Extraction of Alkali Metals as Their Poly-Iodides
Authors: Akaza Ikuko
Published: July 2006

It has been known that alkali metal ions can be extracted into nitrobenzene as their poly-iodides, but the extraction has not been attempted for various salts of alkali metals except in the case of their iodides. In this research ammonium iodide and elemental iodine were preferentially added to the extraction system in order to convert various alkali metal salts into poly-iodides. Ammonium iodide should be larger than the equivalent amount to an alkali metal present in an aqueous solution. The ratio of free iodine to ammonium iodide is an important factor; when the ratio is more than three, a higher distribution ratio is obtained. The ratio of iodine to iodide in the organic phase after the extraction is estimated to be six; therefore, the extracted species seems to be heptaiodide. The extractability of alkali metals increases in the order: Li–Na–K–Rb–Cs, and the distribution ratio decreases with the increase in the amount of metal ions taken in. Back extraction is achieved by shaking the organic phase with 10 m nitric acid. The separation factor between the metals is too low for them to be separated from one another.
A Geochemical Study of the Fumarolic Bismuthinite from Showashinzan
Authors: Mizutani Yoshihiko
Published: July 2006

In an active fumarole on the dome of the Showashinzan volcano, Hokkaido, Japan, a crystalline sublimate was found. It is lead grey, with a metallic luster, and forms loose clusters of aciculer crystals. X-Ray diffraction, spectrographic and micro-chemical analyses have been made of the sublimate. The results indicate that the sublimate consists of bismuthinite Bi2S3, with traces of lead, zinc, aluminum, copper, iron and titanium. A colorimetric determination has also been made of the bismuth in the fumarolic gases from Showashinzan. The variation in the bismuth content of the gases with the gas temperature suggests that, when the temperature falls to about 500°C, bismuth compounds lose their volatility in the gases and are precipitated to form a sublimate. On the assumption that the chemical equilibrium is established in the gases, the stability of bismuth minerals and a possible reaction for the formation of bismuthinite in the gases have been discussed, and it has been suggested that the bismuthinite is formed by the 2BiCl3+3H2S=Bi2S3+6HCl reaction in the gases.
Free Radical Reactions in Organic Electrode Processes. II. The Anodic Aroyloxylation of Anisole
Authors: Koyama Kikuhiko , Yoshida Kunihisa , Tsutsumi Shigeru
Published: July 2006

Electrolyses of an acetonitrile solution of benzoic acid containing triethylamine have been carried out in the presence of anisole by the use of a platinum anode in an undivided cylindrical glass cell under various conditions. The electrolysis with benzoic acid at 15–23°C gave o- and p-methoxyphenyl benzoates (60%) as the main products, but the m-isomer could not be detected. The ratio of the isomers was 2 (ortho) : 1 (para). The other products identified in this experiment were carbon dioxide and biphenyl. The yield of the benzoates decreased when the electrolysis temperature was raised. The peaks of carbon dioxide and biphenyl on the vapor phase chromatograms in the experiment at 84°C, on the contrary, were relatively large compared with that observed in the low temperature electrolysis. Analogous products were obtained from the electrolysis of both p-toluic and p-anisic acids. These results have been compared with those obtained from the thermal decomposition of diaroyl peroxide in anisole. The mechanism of this anodic aroyloxylation of anisole has also been discussed.
Further Study of Syntheses of dl-2,3-Dicarboxycyclopentylacetic Acids
Authors: Kurosawa Kazu , Obara Heitaro
Published: July 2006

The assignment of the configuration of racemic trans-trans and cis-cis-2,3-dicarboxycyclopentylacetic acid previously proposed has been confirmed by the syntheses of these compounds through other unambiguous reaction sequences. The trans-cis-isomer has been prepared by the epimerization of the 3-carboxyl group of the cis-cis-isomer, but the attempt to synthesize the fourth isomer (cis-trans) has been unsuccessful.
Silent Discharge Reactions in Aqueous Solutions. II. An Acidic Aqueous Solution of Ceric Sulfate in Atmospheres of Helium and Argon
Authors: Yokohata Akira , Tsuda Satoru
Published: July 2006

In an atmosphere of helium or argon, the silent discharge reaction of an acidic aqueous solution of ceric sulfate has been investigated from the point of view of radiation chemistry. The results show the reduction of ceric ions to cerous ions. The situation is very similar to that in the case of radiation chemistry. From the known mechanism of the radiolysis of a ceric sulfate solution, the yield of “hydrogen atoms minus hydroxyl radicals” has been determined. Also, combining this yield with that of “hydrogen atoms plus hydroxyl radicals” previously obtained gave the respective yields of hydrogen atoms and hydroxyl radicals. Moreover, on the basis of the value of the dose rate previously determined, the G values of the hydrogen atom, the hydroxyl radical and the cerous ion were determined to be as follows: in helium: G(H)=1.1,G(OH)=1.6,G(Ce3+)=1.6; in argon: G(H)=0.6,G(OH)=0.7,G(Ce3+)=2.9. On the basis of these results, it may be concluded that the silent discharge reactions in an aqueous solution in inert gas can well be interpreted in terms of the radiolysis caused by the ionizing radiation of high LET.
The Interaction of Cumulene Systems with Organometallic π-Complexes. IV. Novel π-Allyl Complexes Obtained from the Reactions of Allene with Iron and Cobalt Carbonyls
Authors: Nakamura Akira
Published: July 2006

2,2′-Bi-π-allylene(hexacarbonyl)di-iron, [(OC)3Fe]·(Remark: Graphics omitted.)·[Fe(CO)3], was found to be a product of the reaction of allene with Fe3(CO)12. A study of the NMR spectrum, however, showed that a rapid valence tautomerisation takes place, even at −10°C between the 2,2′-bi-π-allylene structure and the related butadiene-type structure. In the presence of an excess of Co2(CO)8, allene yielded the [(C3H4)Co(CO)3]2 complex. The structure of this complex in which a (Remark: Graphics omitted.) skeleton was bound to two Co(CO)2 groups via π-allyl and acyl groups, was suggested.
Studies of C-Substituted Tartaric Acid. I. The Preparation of Optically Active 2-Methyltartaric and 2, 3-Dimethyltartaric Acid
Authors: Tatsumi Susumu , Izumi Yoshiharu , Imaida Masami , Fukuda Yoshio , Akabori Shiro
Published: July 2006

Two racemic forms of 2-methyltartaric acid were prepared, and their optical resolutions were performed. Four optically active isomers were obtained. 2, 3-Dimethyltartaric acid was also prepared and separated into two isomeric optically inactive forms. The isomer with the higher melting point could be resolved into two optically active isomers, but the other, with the lower melting point, could not. The former was, therefore, assigned to the racemic configuration, and the latter, to the meso configuration.
Polyesters Containing Carbazole Rings in the Main Chain. III. Syntheses of New Polyesters from Carbazole-dibasic Acids
Authors: Nagai Yoshio , Huang Chin-Chuan
Published: July 2006

Several new polyesters were synthesized by the reaction of ethylene glycol with such carbazoledi-carboxylic acids as carbazole-3, 6-dicarboxylic, 9-ethylcarbazole-3, 6-dicarboxylic, carbazole-3, 6-dibutanoic and 9-methylcarbazole-3, 6-dibutanoic acid in the presence of various catalysts.
The Heats of Mixing for Binary Mixtures. III. The Intermolecular Energy of Hydrogen Bonding between Alcohol and Several Other Polar Molecules
Authors: Murakami Sachio , Fujishiro Ryoichi
Published: July 2006

Calorimetric measurements of the heat of mixing have been made at 25.0±0.01°C for binary mixtures of n-butanol with polar liquids (acetonitrile, acetone, n-butyl ether, and n-butyl amine), and for binary mixtures of polar liquids with n-hexane. The calorimeter for measuring the heats of mixing was of twin type, and a thermomodule, HTM 0516 type (Sharp Electric Co., Ltd., Osaka) was used as the temperature-sensing device. By plotting the values of the heat of mixing, ΔHx1m, against the mole fraction of component 1, x1, and by extrapolating the curve to an infinite dilution (x1→0) for each system, the heats of mixing per mole of component 1 at an infinite dilution (\undersetx1→0limΔHx1m) were obtained graphically. By using the values of \undersetx1→0limΔHx1m obtained for these systems and by using the same treatment as that described in a previous paper [S. Murakami, K. Amaya and R. Fujishiro, This Bulltein, 37, 1776(1964)], the intermolecular hydrogen bond energies between alcohol and polar molecules were estimated; it was found that the strength of the hydrogen bond was in the following order: n-butyl amine>n-butyl ether>acetone>acetonitrile. This agrees with the results obtained from the spectroscopic study.
Copolymerization Characteristics of Methyl Acrylate and Methyl Methacrylate. II. Analysis of Methyl Acrylate-Methyl Methacrylate Copolymers by Infrared Spectroscopy
Authors: Kotera Akira , Shima Mikiko , Akiyama Katsuo , Kume Masako , Miyakawa Machiko
Published: July 2006

The infrared absorption spectra of polymers and copolymers of methyl acrylate and methyl methacrylate have been measured, and then used as the basis of a spectrophotometric method for the analysis of the copolymers. The 6.73 μ band, which may be due to methyl (–C–CH3) vibration, was selected as the key band for measuring the methyl methacrylate component, while the 6.89 μ band was used as the standard. The monomer reactivity ratios for copolymerization of methyl acrylate-methyl methacrylate system have been determined to be r1=0.5±0.1, and r2=2.3±0.4 (M1 methyl acrylate, M2; methyl methacrylate) at 130°C. These values are in good agreement with those previously obtained by the deuterium tracer method. It has also been shown that the procedure used in this study is appropriate for the analyses of methyl acrylate-methyl methacrylate copolymers.
The Electronic Structures and Electronic Spectra of Some Aliphatic Nitroso Compounds
Authors: Tanaka Masashi , Tanaka Jiro , Nagakura Saburo
Published: July 2006

The electronic structures and electronic spectra of 1-chloro-1-nitrosocyclohexane, nitrosyl chloride, methyl nitrite and dimethylnitrosoamine were studied by making molecular orbital calculations and by measuring the electronic absorption spectra. Concerning 1-chloro-1-nitrosocyclohexane, the n→π* and π→π* bands were observed at 650 and 160 mμ respectively. The conjugation effect of electron donors such as Cl, OCH3 and N(CH3)2 upon the electronic spectrum of the nitroso group was studied. The intramolecular charge-transfer bands characteristic of the donor-acceptor interaction were found at 190, 210 and 230 mμ for nitrosyl chloride, methyl nitrite and N,N-dimethylnitrosoamine respectively. This shows that the intramolecular charge-transfer bands appear at longer wavelengths in the order of the increasing ability of the electron donors, Cl<OCH3<N(CH3)2. On the other hand, the n→π* bands shift to shorter wavelengths in the same order.
The Intramolecular Interaction between the N–H Group and π-Electrons. IV. The Energetics of the Interaction
Authors: Oki Michinori , Mutai Kiyoshi
Published: July 2006

The thermodynamic parameters for the intramolecular interaction between the N–H group and the π-electrons in N-benzylanilines were determined from the temperature dependence of the N-H stretching absorptions. A comparison of the −ΔH’s with those for the O–H···π interaction indicates that there is no appreciable difference between the interactions involving the N–H and the O–H groups. The −ΔH’s are less than 2 kcal./mol., this figure being considered to be a borderline differentiating the X–H···π interaction from the ordinary hydrogen bond. The wave number shift accompanying the interaction cannot be a measure of the −ΔH in the N–H group, nor be indicative of the difference between two groups. The −ΔH was found to be closely related with the equilibrium constant in these derivatives.
Intramolecular Interaction between Hydroxyl Group and π-Electrons. XX. Conformationally-fixed o-Vinylphenols
Authors: Oki Michinori , Iwamura Hiizu , Onoda Takeru , Nishida Michiko
Published: July 2006

1, 2-Dihydro-5-hydroxy-8-methoxy-3-methylnaphthalene (III) was prepared, starting from 5,8-dimethoxy-α-tetralone, via 8-hydroxy-5-methoxy-2-methyl-1-keto-1,2,3,4-tetrahydronaphthalene. The O–H stretching absorptions (νo−h) and the ultraviolet absorptions of III, 1, 17 β-dihydroxy-4-methylestra-1,3,5(10), 9(11)-tetraene (IV), and the related naphthols were measured and compared with those of o-isobutenylphenol. IV showed a νo−h at 3532cm−1 which is assigned to the hydroxyl group taking part in the strong interaction with the π-electrons on the ethylenic group; it corresponds well in its location to the lowest frequency band of o-isobutenylphenol. The previous assignment of this band to the conformer II with the double bond syn to the hydroxyl was thus confirmed. III showed only a symmetric band at 3618cm−1, which was assigned to the free νo−h and could not be a model for the conformer with a νo−h at 3576cm−1, presumably because of the more planar structure for the overlap between the orbitals of the hydroxyl group and the ethylenic group.
Kinetic Studies of the Oxidation of Aldopentoses: l-Arabinose and d-Xylose Oxidized by Hexacyanoferrate(III) in an Alkaline Medium
Authors: Srivastava Rajendra Kumar , Nath Narendra , Singh M P
Published: July 2006

The kinetic studies of the oxidation of l-arabinose and d-xylose have been carried out using potassium ferricyanide in the presence of sodium hydroxide and sodium carbonate. The order of the reaction has been found to be zero with respect to ferricyanide and first with respect to the reducing sugar. The reaction rate is also directly proportional to the hydroxide ion concentration. The reaction also has a very small induction period.
Effects of Pressure on the Chemical Properties of the Solid Surface. III. The Catalytic Activity and the Structure of the Compressed Tungstic Acid
Authors: Ogino Yoshisada , Kawakami Takeshi , Matsuoka Toru
Published: July 2006

In order to investigate the surface properties of tungstic acid samples which had been compressed at pressures of 640–3840 kg./cm2, experimental studies concerning the catalytic activity for the vapor-phase hydration of propylene, the specific surface area, the pore structures, the surface acidities and the crystal structures were carried out. According to the experimental results, both the catalytic activity and the surface acidity became higher as the compressing pressure of the sample was increased, whereas the specific surface area remained practically constant. Further, a relation between the surface acidity and the crystal structure was deduced from X-ray diffraction studies. Namely, the crystal structure of the reduced sample approached the structure of H0.1WO3 from a WO3-like structure as the compressing pressure was increased. In other words, samples with higher compressing pressures had crystal structures of a higher proton content. In addition to the above results, the total pore volume, the mean pore radius, the apparent activation energy, and the frequency factor became smaller as the compressing pressure was increased. On the basis of these experimental results, it was deduced that the catalytic activities of the compressed samples are affected by intra-particle diffusion.
CHEMISTRY OF THIO-CHOLINE HALIDE (TRIMETHYLTHIO-ETHYL AMMONIUM HALIDE). NEW THIO-CHOLINE BROMIDE AND ITS DERIVATIVES. I
Authors: Harada Taichi
Published: July 2006

1. Thio-choline bromide was prepared by heating bromocholine bromide with 2-thio-uracil or 4-methyl-2-thio-uracil with water in a closed tube or pressure bottle at 150°C and 170°C. for two and five hours respectively. The compound is hygroscopic in nature, and is very soluble in both alcohol and water. It decomposes at 243°C. on heating. Its isoelectric point was found to be 7.00.

2. By heating with hydrobromic acid the compound is easily oxidized to its disulphide, which is a syrupy and less pronounced ionizable substance, in aqueous solution.

3. On treating an aqueous solution of this compound, with an excess of silver oxide, and neutrallizing with hydrobromic acid and heating on the steam bath, an insoluble white asbestos-like crystalline substance was formed. It appears to be the following formula:

(Remark: Graphics omitted.)

The compound is slightly soluble in alkaline solution. It decomposes at 214°C.
ON THE PROMOTER ACTION IN THE CATALYTIC OXIDATION OF METHANE WITH STEAM
Authors: Kubota Bennosuke , Yamanaka Tatsuo
Published: July 2006

In the catalytic oxidation of methane with steam in the presence of nickel, the promoter action of several metallic oxides were investigated.

It was found that the largest quantity of CO2 was obtained by employing the catalyst promoted with Al2O3, whilst when water vapour was regulated the catalyst promoted with MgO gave the largest yield of CO.

These results might possively lead one to suppose that the reaction may be looked upon as taking place successively in the manner:

(Remark: Graphics omitted.)

and as the beneficial effect of promoters in these reactions may be to transfer water molecules to the reaction centers of the catalyst where the action of water on methane is carried out, the products may be determined according to the adsorbing intensity of water molecules and the size of the promoter. Thus it seems to us that the results we obtained are quite in good agreement with Balandin’s “ Multipletthypothese.”
ELECTRONIC CONCEPTION IN ORGANIC CHEMISTRY. III. DISSOCIATION AND SEMIHYDROBENZOIN REARRANGEMENT OF αα-DIMETHYL-β-ACETYL GLYCOL
Authors: Migita Masao
Published: July 2006

In order to see the effect of the carbonyl group, action of hot dilute and cold concentrated sulphuric acid on αα-dimethyl-β-acetyl glycol was studied.

This keto-glycol was found to undergo semihydrobenzoin rearrangement and dissociation into acetone and acetol simultaneously. The primary product of the semihydrobenzoin rearrangement of this glycol being decomposed during the subsequent treatments, only the secondary products, methyl-isopropyl ketone, could be isolated. The dissociation of dimethylacetyl-glycol was started not only by acid, but also by alkali. These results can be easily deduced from the electronic interpretation given in previous papers.

That the dissociation of dimethyl-acetyl glycol takes place merely by distillation was directly proved by identifying acetol by a new method.

Methods to identify acetone, methyl-ethyl ketone, methyl-isopropyl ketone, acetol and dimethyl-acetyl glycol with limited quantity of the sample in presence of one another, were carefully studied and established.
The Thermal Decomposition of Hexamminenickel(II) Complexes
Authors: Tanaka Nobuyuki , Kagawa Masahiro , Kamada Minoru
Published: July 2006

From the thermogravimetric analysis, hexamminenickel(II) complexes were confirmed to decompose in two or three steps through lower ammine intermediates NiXm·nNH3: n=2, 1 and m=2 for X=Cl; n=2 and m=2 for X=I, Br; n=4 and m=2 for X=NO3 and n=2, 1/2 and m=1 for X=SO4. The diffuse reflectance spectra of these intermediates have been measured in a range between 5000 to 27000 cm−1, and they suggested that these intermediates may be polymers in which nickel ions were octahedrally coordinated with ammonia molecules and bridging halogen atoms. The infrared absorption spectra of these intermediates obtained in a range between 5000 and 60 cm−1 are also reported.
The Selective Reduction of Aromatic Compounds by Electrolysis. I. Reduction of Naphthalene by Electrolysis
Authors: Misono Akira , Osa Tetsuo , Yamagishi Takamichi
Published: July 2006

The direct electro-reduction of naphthalene was investigated in various solvents, mainly in an acetonitrile-water solution using supporting electrolytes containing tetraethylammonium and tetra-n-butylammonium cations. The main reduction product was 1,4-dihydronaphthalene, though small amounts of 1,2-dihydronaphthalene and tetralin were also detected. Under optimum conditions, the selectivity and the current efficiency of the formation of 1,4-dihydronaphthalene were 98% and 86.4% respectively. It was found that the water concentration and the solvent had a significant influence on the reduction products and the current efficiency. 1,4-Dihydronaphthalene is mainly formed through the step-by-step addition of two electrons and protons. In addition, 1,4-dihydronaphthalene may be formed by the protonation of the dianion formed by the disproportionation of the anion radical. Further, it was proposed that the formation of the tetraethylammonium radical might partly occur by means of the electron transfer from the anion radical of naphthalene to the tetraethylammonium cation, besides the direct electron transfer to the cation from the electrode.
A New Synthesis of Substituted 8-Aminopurine Derivatives
Authors: Yoneda Fumio , Higuchi Masatsugu , Matsumura Takafumi , Senga Keitaro
Published: July 2006

The treatment of 6-amino-5-nitrosopyrimidines with Vilsmeier-type reagents (substituted formamides and phosphorus oxychloride) afforded substituted 8-aminopurines; the treatment of 6-amino-4-hydroxy-2-methyl-5-nitrosopyrimidine gave 2-chloromethyl-8-dimethylamino-6-hydroxypurine.
Synthesis of Alanosine
Authors: Isowa Yoshikazu , Kurita Hideaki , Ohmori Muneki , Sato Masanari , Mori Kaoru
Published: July 2006

Dl-2-Ammo-3-(N-tosyl-N-benzyloxyamino)propionic acid (Dl-V) was synthesized starting from ethyl 2,3-dibromopropionate and N-tosyl-O-benzylhydroxylamine. l-2-Benzoylamino-3-(N-benzoyl-N-hydroxyamino)propionic acid anilide (l XIV) obtained via the enzymatic resolution of Dl-2-benzoylamino-3-benzyloxyaminopropionic acid (Dl-IX) was converted by acid hydrolysis to l-2-amino-3-hydroxyaminopropionic acid (l-II). The nitrosation product of the amino-hydroxyamino acid (l-II) was identical with alanosine (l-I).
Reaction of Mo5+ Formed on Supported Molybdena Catalysts with Oxygen or Water
Authors: Akimoto Masamichi , Echigoya Etsuro
Published: July 2006

Reactivity of Mo5+ formed on supported molybdena catalysts with oxygen or water was investigated by means of ESR spectroscopy. Mo5+ formed on the alumina carrier could not be oxidized with gaseous oxygen even at 450 °C and was poisoned by water at 200 °C losing its ESR signal. The Mo5+ formed on the titania carrier disappeared by reaction with either oxygen or water. The mechanism for the reactions was investigated and the different reactivities of Mo5+ with oxygen as regards carrier effect on the structure were discussed.
Effect of Additives on Thermal Decomposition of Basic Magnesium Carbonate
Authors: Amita Kayoko , Hashizume Genzo
Published: July 2006

The effect of eleven halides on the thermal decomposition of basic magnesium carbonate (4MgCO3·Mg(OH)2·4H2O) has been studied by means of thermogravimetry (TG), differential thermal analysis (DTA) and gas chromatography. The size of crystallite of magnesium oxide prepared by heating the carbonate containing halide was determined by X-ray diffractometry, the oxides being studied by transmission electron microscopy. The thermal decomposition of basic magnesium carbonate was influenced by the addition of beryllium chloride tetrahydrate, magnesium chloride hexahydrate, calcium chloride hexahydrate and magnesium bromide hexahydrate. The DTA curve was changed with the amount of additive, i.e., three endothermic peaks (at about 300, 430, and 530 °C) and an exothermic peak (at 490 °C) turned to only two endo-thermic peaks in the case where the molar ratio of an additive to the carbonate exceeded 0.005, the peak at higher temperature becoming sharp with shift toward lower temperature. The results of TG of basic magnesium carbonate corresponded to those of DTA. Gas chromatographic data showed that the composition of evolved gas varied with temperature. The activation energies of decarbonation and dehydration were obtained by gas chromatography by use of Freeman-Carroll’s technique. Increase in the amount of additive caused a decrease in the activation energy of decarbonation, but not in that of dehydration except for magnesium bromide hexahydrate. The size of crystallite of magnesium oxide prepared by calcination at 600 °C for 2 hr, increased with the increase in the amount of additive.
A Study of Solute–Solvent Interaction in Solvents of Medium Dielectric Constant from the Apparent Molal Volume Data. I
Authors: Gopal Ram , Agarwal D K , Kumar Rajendra
Published: July 2006

A study of the apparent molal volume (φv) of some common salts and the tetraalkylammonium iodides in DMSO has been reported in this communication. All the salts studied here, including those containing the larger R4N+ ions, have a positive slope in the φv  vs. \sqrtC curves, indicating a strong ionic interaction, apparently due to the medium dielectric constant of the solvent. This dielectric constant also promotes ion-association at higher concentrations and thus mutual penetration of the R4N+ ions is prevented. As a result, no negative slope in the φv  vs. \sqrtC curves of the larger R4N-iodides is observed in this solvent. The effect of temperature on the limiting apparent molal volume, φ°, reveals that the ion-solvent interaction is comparatively stronger in the non-hydrogen bonded solvents like DMSO and DMF than that in strongly hydrogen-bonded solvents like NMA and NMP. Addition of a CH2-group to each of the four R-chains of the R4N+ ion increases its volume by about 70 ml per mole in DMSO, DMF, and NMA.
The Bromination of p-Nitrophenol in Acetic Acid
Authors: Sridhar N , Rajaram J , Kuriacose J C
Published: July 2006

Bromination of aromatic substrates like p-bromophenol, anisole, etc. by molecular bromine in acetic acid follows the rate expression, Rate=k[ArH][Br2]+k′[ArH][Br2]2. For the bromination of p-nitrophenol in acetic acid, variable orders in bromine and p-nitrophenol have been observed on varying the concentrations of reactants. A rate expression of the type, Rate=k[ArH][Br2]+k′[ArH][Br2]2+k″[ArH]2[Br2] has been proposed. The observations conform to a general mechanism for bromination provided a bromine molecule, a substrate molecule or solvent molecules can be the electrophile in the rate determining step, depending upon the conditions employed for the reaction.
The Simultaneous Detection of Gas Phase Atoms and Free Radicals Produced in a Microwave Discharge by ESR Spin Trapping Methods
Authors: Janzen Edward G , Kasai Toshio , Kuwata Keiji
Published: July 2006

The simultaneous detection of gas phase atoms and free radicals produced in a 2450 MHz discharge is demonstrated by use of a previously described technique called spin trapping. The atoms or radicals are allowed to react with phenyl N-t-butyl nitrone to give relatively stable nitroxide radicals. The ESR spectra of these nitroxides provide the analytical data for identification of the atoms or radicals trapped.
Photovoltaic Effect of Aromatic Diamine in Solution
Authors: Imura Takeshi , Takagi Seishi , Kawabe Kazuo
Published: July 2006

Photovoltaic behaviors are described of N,N,N′,N′-tetramethyl-p-phenylenediamine dissolved in various polar solvents. Positive photovoltage is observed on the illuminated electrode in highly polar solvents such as methanol and acetonitrile, and none in moderately polar ones such as ethanol and acetone. The influence of a few electrode metals on photovoltage has been examined. The electromotive force increases with the work function of metals from tantalum to platinum. Conditions for the appearance of photovoltage are discussed and the photo-ionization process of the aromatic diamine is considered.
Reductions of Cobalt(III) Complexes by Iron(II) Chelates. I. The Kinetics and Mechanisms of the Reductions of Acidopentaamminecobalt(III) Complex Ions by Iron(II) Chelates of Nitrilopolycarboxylic Acids
Authors: Kurimura Yoshimi
Published: July 2006

Kinetic studies have been made of the reactions of FeEDTA2− with complex ions of the Co(NH3)5X2+ (X=F−, Cl−, Br−, I−, NO3−, NCS−, and N3−) type. The pattern of reactivity suggests that FeEDTA2− reacts with Co(NH3)5X2+ mainly through an innersphere mechanism. The variation in the rate of the reactions of FeIIZm− (Z=EDTA, CyDTA, EDTA-OH, and DTPA), in which the Z ligand is varied, with Co(NH3)5Cl2+ can be explained in terms of the steric effect, the charge effect, and the stabilization effect.
Thermal and Spectrophotometric Studies of 8-Mercaptoquinoline-5-sulfonic Acid and Its Sodium Salt
Authors: Sekido Eiichi , Tanaka Junichi , Masuda Yoshitaka
Published: July 2006

Thermal and spectrophotometric studies of 8-mercaptoquinoline-5-sulfonic acid and its sodium salt synthesized by an improved method are reported. In order to determine the best formula for the weighing of organic reagent, the thermal stabilities of 8-mercaptoquinoline-5-sulfonic acid and its sodium salt and the amount of water of crystallization were examined with a thermal balance. It was found that the disodium dihydrate was of the best form. The ultraviolet and visible absorption spectra in aqueous-ethanol solution were measured, the tauto-meric constant Kt between neutral and zwitterion forms being estimated and acid dissociation constants obtained spectrophotometrically. The absorption spectra and the equilibrium constants of the reagents were compared with those of 8-mercaptoquinoline, 8-hydroxyquinoline and 8-hydroxyquinoline-5-sulfonic acid.
Stability of Fused Rings in Metal Chelates. X. Structures and Stability Constants of the Copper (II) Complexes of Tripeptides Composed of Glycine and/or β-Alanine
Authors: Yamauchi Osamu , Nakao Yasuo , Nakahara Akitsugu
Published: July 2006

On the basis of comparative studies of the equilibria involving copper(II) and triglycine (G·G·G), glycylglycyl-β-alanine (G·G·β-A), glycyl-β-alanylglycine (G·β-A·G), or β-alanylglycylglycine (β-A·G·G), the structures of the complexes formed at various pH values and the structure-stability relationship between the fusedring chelates have been discussed in reference to the equilibrium constants determined by potentiometric titration at 25°(μ=0.1 (KNO3)) and the properties of the copper(II) chelates isolated. For each tripeptide, the stability constant K1 for the 1: 1 complex and the constants for the deprotonation reactions Kc1 and Kc2 were calculated by the method of non-linear least-squares. For G·G·G, G·G·β–A, and G·β–A·G, the equilibrium indicating the formation of a protonated complex was detected at pH 3.5–4.5. The relatively small difference in the logK1 values (5.25–5.60) and the logKc1 values (5.23–5.36) and the larger difference in the −logKc2 values (5.54–6.73) have been interpreted in terms of the steric requirements around copper(II) in the fused-ring chelates. Relative stabilities of the fused-ring systems in the deprotonated chelates have been inferred from the K1Kc1Kc2 values to be in the order 5-6-5(G.β-A·G-Cu(II))\simeq6-5-5(β-A·G·G-Cu(II))>5-5-6(G·G·β-A-Cu(II))>5-5-5(G·G·G–Cu(II)).
Studies of Ruthenium Complexes. IV. The Solvent Effect on the Isotopic Ligand-exchange Reaction of the cis- Dibromotetraammineruthenium(III) Complex
Authors: Ohyoshi Akira , Shinohara Tetsuo , Hosoyamada Yoshihiro , Yamada Takato , Hiroshima Yutaka
Published: July 2006

The isotopic ligand-exchange reactions of cis-dibromotetraammineruthenium(III) were studied in aqueous and methanol-water solutions in order to distinguish them from those in the case of the monobromocomplex and in order to ascertain the role of the water molecule with respect to the reaction mechanism. In an aqueous solution, the reaction proceeds through the rate-determining aquation step with the SN2 mechanism: Ru(NH3)4Br2++H2O→Ru(NH3)4(H2O)Br2++Br−, Ru(NH3)4(H2O)Br2++*Br−→Ru(NH3)4Br*Br++H2O. This result is similar to that for the monobromocomplex. In the methanol solution (H2O∼1.5%), the exchange reaction proceeds through the SN1 mechanism: Ru(NH3)4Br2+→Ru(NH3)4Br2++Br−, Ru(NH3)4Br2++*Br−→Ru(NH3)4Br*Br+. When the concentration of water becomes very low, the number of solvated water molecules decreases; therefore, the coordinated bromide ion may easily be liberated. When the concentration of water is higher than 10%, the rate constant increases with the increase in the water concentration. Since the electronic spectra did not change during the exchange reaction, it would seem that the water molecule attacks a cis-position as a nucleophile. These results can be interpreted by postulating a hydrogen-bond between the proton of the water molecule and the coordinated bromide ion.
The Synthesis of Some N,N-Dialkylselenocarbamate Complexes of Tin(IV), and Their Infrared and PMR Spectra
Authors: Tanaka Koji , Araki Shigeo , Tanaka Toshio
Published: July 2006

Several N,N-dialkylselenocarbamate complexes of tin(IV), (CH3)2Sn[OSeCNR2]2 (1), (CH3)2ClSn[OSeCNR2] (2) (R=CH3 and C2H5) and (CH3)3Sn[OSeCN(CH3)2] (3), have been prepared, and their infrared and proton magnetic resonance spectra have been examined. The results indicate that in 1 and 2 the selenocarbamate ligands are coordinated to the tin atom in a bidentate manner, although the coordination of the oxygen atom is weak. On the other hand, 3 has a tetra-coordinate tin with a free carbonyl bond. The configurations of these complexes are discussed and compared with those of the corresponding thio-, dithio-, diseleno-, and thioselenocarbamate complexes of tin(IV).
Add nets of Neodymium(III) and Lanthanum(III) Acetylacetonate with some Bidentate Organic Bases
Authors: Yoshida Isao , Kobayashi Hiroshi , Ueno Keihei
Published: July 2006

Several bidentate uncharged organic base adducts of neodymium(III) and lanthanum(III) acetylacetonate were prepared by the reaction of the free bases with tris(acetylacetonato)neodymium(III) monohydrate and tris-(acetylacetonato) lanthanum(III) dihydrate in ethyl acetate, respectively. Elemental analyses, molecular weight determinations, NMR, IR, and visible absorption spectra indicate that the adducts are of the general formula Ln(AA)3(BB), where AA, BB, and Ln denote acetylacetonate ion, bidentate uncharged base and lanthanide ion, respectively. Thermal stability of the base adducts as well as the hydrates was studied by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). Coordination of the additional ligand having reactive hydrogen atoms resulted in poor thermal stability of the addition complexes. This might be explained by assuming that the coordinated acetylacetonate ion reacts readily with the reactive hydrogen atom of the neighboring ligand to liberate acetylacetone molecule, though the nature of the resulting pyrolyzed products is unknown.
Hexaammine, Tris(ethylenediamine), Glycinato, and l-Alaninato Complexes of a Triperiodatotetracobaltate(III) Condensed Anion
Authors: Ama Tomoharu , Hidaka Jinsai , Shimura Yoichi
Published: July 2006

Malaprade’s triperiodatotetracobaltate(III) heteropoly condensed acid, H3[Co4I3O18(OH2)6]·nH2O, was characterized by examination of its coordination derivatives with ammonia, ethylenediamine, glycinato, or l-alaninato ligands. It was concluded that the ion of parent acid and its derivatives, [Co4I3O18X6]n− (X6=(OH2)6, (NH3)6, en3, (OH2)4(gly), or (OH2)4(l-ala)), commonly have a hexol-like arrangement of four cobalt(III) octahedra so that the whole skeletons are based on the Anderson structure. The hexol-like configuration is chiral, this being demonstrated by the separation of two diastereomers of [Co4I3O18(OH2)4(l-ala)]4− ion.
Selective Formations of Several Carboxylic Acids by Carbonylation in the SbCl5–Liquid Sulfur Dioxide System
Authors: Yoshimura Masakatsu , Nojima Masatomo , Tokura Niichiro
Published: July 2006

The carbonylations of cis- and trans-4-t-butyl-1-methylcyclohexanols, exo- and endo-2-methyl-2-norbornanols and exo- and endo-2-norbornanols were carried out in SbCl5–liq.SO2 at −70°. From both the cis- and trans-4-t-butyl-1-methyl-cyclohexanols, cis-4-t-butyl-1-methylcyclohexanecarboxylic acid was formed exclusively in an excellent yield (over 90%). Both exo- and endo-2-methyl-2-norbornanols gave only endo-2-methyl-exo-2-norbornylcarboxylic acid in a high yield. The reason for the stereoselectivity of the reactions was discussed.
Peptides. IV. Racemization Suppression by the Use of Ethyl 2-Hydroximino-2-cyanoacetate and Its Amide
Authors: Itoh Masumi
Published: July 2006

Racemization suppression by the addition of ethyl 2-hydroximino-2-cyanoacetate (IIIa) or 2-hydroximino-2-cyanoacetamide (IIIb), during coupling stages in peptide synthesis, was studied. The effectiveness of IIIa was compared with these of known additives by the help of Bodanszky’s test, which is a simple and accurate method for racemization detection.
Microwave Spectrum of Arsenic Trifluoride in the Excited Vibrational State
Authors: Chikaraishi Toshio , Hirota Eizi
Published: July 2006

The microwave spectrum of arsenic trifluoride was observed in the excited states of all the normal vibrations. The rotational constant at the equilibrium state was determined, and the equilibrium As–F distance was calculated to be 1.7044 Å assuming the FAsF angle to be 95°58′. The l-type doubling constant, q4, and the asymmetry parameter, η, of the As nuclear quadrupole coupling constant were determined in the v4=1 to be 10.24±0.02 MHz and −0.005±0.01, respectively.
The pH-dependent Variation of the Absorption and Circular Dichroism Spectra in Some Ternary Mixed Complexes of Copper(II) Containing Diethylenetriamine and Optically Active Amino Acids
Authors: Murakami Tasuku , Nozawa Tsunenori , Hatano Masahiro
Published: July 2006

The absorption and circular dichroism(CD) spectra of some ternary mixed complexes of copper(II) with diethylenetriamine(dien) and various optically active α-amino acids have been measured in an aqueous solution at various pH values. The amino acid may coordinate to one of the planar positions, with its carboxylate or amino group as a unidentate ligand, in a neutral or a very high pH region. On the other hand, from the red shift of the d–d absorption band and the augmentation of the visible CD magnitude, it seems reasonable to expect that a large portion of the amino acid will form a chelate ring with an axial ligation in the pertinent pH region.
Palladium-Catalyzed Coupling Reaction of Aromatic Compounds
Authors: Yoshimoto Hataaki , Itatani Hiroshi
Published: July 2006

The oxidative coupling reaction of aromatic compounds proceeds catalytically with palladium salt under oxygen pressure. Yields and isomer distributions are attributed to the reaction variables such as temperature, additives, and the nature of the substituent on a benzene ring. Naphthalene was converted mainly into 1-substituted products and o-xylene into 4-substituted products. The coupling of diphenyl ether afforded diphenylene oxide with coupling dimers. An intramolecular two stage dehydrogenation process is proposed.
Studies on Carbamoylation Reactions of Polyethylenimine and Its Low Molecular Weight Analogues with Cyanate Ions
Authors: Okubo Tsuneo , Ise Norio
Published: July 2006

Garbamoylation reaction of ions of polyethylenimine and its low molecular weight analogues, i.e., ethyl-enediamine, triethylenetetramine, and tetraethylenepentamine, with cyanate ions are investigated in the presence of simple-, micelle-, and poly-electrolytes and in their absence. The rate constants are practically independent of the valency of the cations and are much larger than that previously found for the ammonium cyanate reaction. Both of the activation enthalpy and entropy decrease with increasing valency of the cations. Added electrolytes are found to decelerate the reactions. The reactions of poly cations are retarded more strongly by simple cations than by catalyst polycations, whereas those of simple cations are decelerated more effectively by polycations than by simple cations. The kinetic data are discussed thermodynamically in terms of the Bronsted theory and the activity coefficients of the reactant ions. The interaction parameters between reactant electrolyte and added electrolyte are also derived thermodynamically and discussed.
A Theoretical Consideration of the Electron-scavenging Process in Liquid Hydrocarbons. IV. Integral Transforms in the Prescribed Diffusion Approximation
Authors: Yamazaki Hideo , Shinsaka Kyoji
Published: July 2006

The relations of the integral transforms and the integral form between various distribution functions have been discussed in the prescribed diffusion approximation for the Smoluchowski equation. The initial electron distribution from the central-ion cluster in a spur or a track, ω(r, 0); the time dependence of the central value of the electron distribution, ω(0, t); the time dependence of the space-averaged electron concentration, N(t), after pulse irradiation, and the scavenger-concentration dependence of the relative G-value of electron scavenging, Gs(ksCs), as a function of the scavenger concentration, Cs, and the rate constant, ks, are shown to be connected by this diagram of the Laplace transforms and the integral form:

(Remark: Graphics omitted.)

By the use of this relation, the various distribution functions are evaluated from the generalized Gaussian initial distribution. The square-root relationship of the Gs(ksCs) to the scavenger concentration is discussed.