bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoreaction of Tetraphenylcyclopentadienone
Authors: Toshima Naoki , Moritani Ichiro
Published: July 2006

When tetraphenylcyclopentadienone in 2-propanol was irradiated with ultraviolet light under a slow steam of nitrogen, 2, 3-diphenyl-1H-cyclopenta[l]phenanthrene and 1-oxo-2, 3-diphenyl-2, 3-dihydro-1H-cyclopenta[l]phenanthrene were obtained in 10% and 45% yields respectively. That is, a cis-stilbene skeleton cyclized oxidatively to a phenanthrene, while the carbonyl group was reduced to methylene, or olefin, to paraffin. In this reaction, a protic solvent was observed to be favorable. In contrast to this, tetraphenylcyclopentadiene gave no similar cyclized products under the same conditions. The mechanism of this photoreaction is proposed.
Thallic Salt as the Catalyst for the Conversion of Acetylenes to Carbonyl Compounds
Authors: Uemura Sakae , Kitoh Ryohzoh , Fujita Koichi , Ichikawa Katsuhiko
Published: July 2006

It has been shown that the conversion of acetylenes to carbonyl compounds proceeds in various solvents containing thallic salts as the catalyst. Acetylene, methylacetylene, phenylacetylene, propargyl alcohol and its ester, and phenylpropiolic acid and its ester reacted to form acetaldehyde, acetone, acetophenone, acetoxyacetone and acetophenone respectively.
The Photochemical Oxidation Reaction of Benzylic Alcohols in Dimethyl Sulfoxide
Authors: Sato Takeo , Inoue Hiroshi , Hata Kazuo
Published: July 2006

A new photochemical oxidation reaction of benzylic alcohols has been developed by using DMSO as a solvent. The oxidation, which has been performed in an oxygen atmosphere, can be carried out under neutral conditions at room temperature. Detailed studies on the role of DMSO as the solvent were carried out by using benzyl alcohol; it has been established that, in the photo-oxidation in DMSO, the uptake of oxygen was much facilitated compared with the reactions using other solvents, and also that, the benzaldehyde formed was well protected from further oxidation by a complex formation. Three secondary benzylic alcohols gave moderate yields of the corresponding ketones. The same experiments on ten substituted benzyl alcohols have revealed that the presence of an electron-releasing group facilitates the oxidation affording benzaldehydes, whereas an electron-attracting group retards it.
Studies on Reactions of Polypropylene. VIII. The Thermal Degradation of Polypropylene Accelerated by Polyglycidyl Methacrylate
Authors: Mizutani Yukio , Yamamoto Keiichi , Matsuoka Seishiro , Hisano Shigeo
Published: July 2006

The thermal degradation of polypropylene was investigated in the presence of polyglycidyl methacrylate (PGMA) by the use of an extruder under a nitrogen atmosphere. PGMA was found to be effective as an accelerator for the thermal degradation of polypropylene. The accelerating effect of PGMA was attributed to the facts that PGMA was degraded thermally by the zipper-scission mechanism and that the active radical thus generated was effective in accelerating the thermal degradation of polypropylene by the random-scission mechanism. The surviving ratio of the epoxy group throughout the thermal degradation was not as large as had been expected.
Electron Spin Resonance of Anion Radicals of N-Alkyl Phthalimides and Aromatic Acid Anhydrides
Authors: Hirayama Masatoshi
Published: July 2006

The ESR spectra of anion radicals of N-methyl, N-ethyl, and N-n-butyl phthalimides, naphthalic acid anhydride, and pyromellitic acid anhydride were measured in acetonitrile. Both the electrolytic and alkali metal reduction methods were used for the radical generation. The spin densities of these anion radicals were then calculated by McLachlan’s method; the calculated results were partly in agreement with the experimental data. Satellite lines due to three kinds of 13C nuclei in the pyromellitic acid anhydride anion radical were observed; one of these splitting constants was assigned to the position 1.
NMR Spectra of Some Metal Acetylacetonates
Authors: Kawasaki Yoshikane , Tanaka Toshio , Okawara Rokuro
Published: July 2006

The NMR spectra of a series of complexes, XX′Sn(acac)2 (X, X′ =alkyl, aryl and halogen), (CH3)2Pb(acac)2, Cl2Ti(acac)2, Cl2Ge(acac)2, Cl4Sb(acac) and (C6H5)Cl3Sb(acac), have been studied in chloroform. A linear relationship has been found between the chemical shifts of the γ proton and those of the methyl protons of acetylacetone for various type of complexes. In XX′Sn-(acac)2, both τ values decrease with an increase in the electron-attracting power of the substituents, X and X′, and the chemical shifts of these protons are found to be correlated with the Sn–O and C=O stretching frequencies. This behavior can be explained in terms of the inductive effect of the substituents on the tin atom.
Solvent Effect on the Proton Magnetic Resonance Spectra of Dimethyltin Dichloride, Trimethyltin Chloride and Trimethyllead Chloride
Authors: Matsubayashi Gen-etsu , Kawasaki Yoshikane , Tanaka Toshio , Okawara Rokuro
Published: July 2006

The chemical shifts of methyl protons (τ(M–CH3) values) and the coupling constants between the methyl protons and the metal atom JM–CH3 values for dimethyltin dichloride, trimethyltin chloride, and trimethyllead chloride have been measured in thirty-two organic solvents. From the relation between the τ(M–CH3) and the JM–CH3 values, the solvents used here have been classified into four groups. Carbon tetrachloride is representative of the first groups. The second group consists of usual polar organic solvents which can coordinate to the metal atom. The third consists of nitrobenzene, benzonitrile, pyridine, and its derivatives among the solvents studied here. The fourth consists of alkyl- or halogen-substituted aromatic solvents. The configurations of trimethyltin chloride in these solvents have been discussed on the basis of the J119Sn−CH3 values and the intensity of the Sn–C symmetric stretching band relative to that of the asymmetric one. The effects of the temperature and the concentration of the solute on the τ(Sn–CH3) and the J119Sn−CH3 values of trimethyltin chloride have been examined in several solvents.
The Dipole Moments and Polarizabilities in the Excited States of Four Benzene Derivatives from Spectral Solvent Shifts
Authors: Abe Takehiro
Published: July 2006

According to Abe’s expressions for the spectral solvent shifts (Bull. Chem. Soc. Japan, 39, 936 (1966)), the dipole moments, polarizabilities, and solvation energies in the excited states of nitrobenzene, anisole, acetophenone, and p-chloroacetophenone have been estimated. The large dipole moments of 6.78 and 4.23 D for the excited states of nitrobenzene and acetophenone respectively have supported Nagakura and Tanaka’s theory of the intramolecular charge-transfer band.
Heat Measurement by Differential Thermal Analysis
Authors: Ozawa Takeo , Momota Michihiko , Isozaki Hiroshi
Published: July 2006

A new method of measuring the heat of transformation is described; the apparatus used in quantitative differential thermal analysis is calibrated by using an electrical heater inserted in the sample cell. The heats of transformation obtained by using the proportionality coefficient thus calibrated are then compared with the reported values. Good agreements are obtained between them.
The Isomerization Polymerization of 2-Butene
Authors: Iwamoto Masao , Yuguchi Sadao
Published: July 2006

The crystalline polymer has been obtained by polymerizing 2-butene using a Ziegler-type catalyst containing titanium trichloride. 2-Butene was transformed into an equilibrium mixture of 1-butene and cis- and trans-2-butene by the catalytic action of titanium trichloride. When alkylaluminum was present in the system, isotactic poly-1-butene was obtained. These results can be explained by the concept of isomerization polymerization.
The Electronic Spectra of Nitrile N-Oxides and the Solvent Effect on Them
Authors: Yamakawa Masumi , Kubota Tanekazu , Akazawa Hideko
Published: July 2006

The electronic spectra of several substituted benzonitrile N-oxides and 9-anthronitrile N-oxide were recorded in various solvents and compared with those of the corresponding nitriles. The following results were thus obtained. (1) Substituted benzonitrile N-oxides showed a characteristic strong π–π* band at wavelengths much longer than those of the 1La band of the corresponding nitriles. (2) The π–π* band showed a blue shift with an increase in the polarity of the solvents. Quantitative analyses of the solvent effect led to the result of the decreasing dipole moment at π–π* state. (3) The hydrogen-bonding ability of the nitrile N-oxides was found to be weak from experiments on three-component systems and from analyses of the above solvent effect. (4) The electronic structures of the nitrile N-oxides were discussed on the basis of the above-mentioned findings and the measurements of the infrared spectra. It was suggested that the interaction of oxygen 2pπ electrons with the rest of the π electron system should be taken into consideration.
Kinetic Study of Pyrolysis of Toluene-d5
Authors: Takenaka Jumpei , Endo Harumi , Mikuni Hitoshi , Takahasi Makoto
Published: July 2006

Reaction mechanism of pyrolysis of toluene was studied with toluene-d5 of high isotopic purity. The rate constant of pyrolysis of toluene-d5 in gas phase was determined to be k=1011.5±0.3×exp(−70±1 kcal/mol) (sec−1) and compared with that of toluene. Hydrogen isotope mixtures produced in the pyrolysis of toluene-d5 were collected and analyzed by mass spectrometer. Formation of some amount of D2 is confirmed, and it is concluded that the fission of ring C–D bond is involved to some extent in the pyrolytic reaction of toluene-d5 at high reaction temperatures. The ratio of rate constants of abstraction type (kD–H⁄kH–H) is also determined, and the difference of the activation energies between kD–H and kH–H is found to be approximately 14 kcal/mol.
The Polarographic Behavior of the Condensation Products of o-Phenylenediamine with Biacetyl and with Methylglyoxal, and Its Application to the Determination of Biacetyl and Methylglyoxal
Authors: Wasa Tamotsu , Musha Sôichirô
Published: July 2006

Both the condensation product of o-phenylenediamine (OPD) with methylglyoxal and that with biacetyl produce two diffusion-controlled reduction waves, each corresponding to a one-electron transfer, at pH values below 3 (E1⁄2:−0.220 V and −0.332 V vs. SCE for the methylglyoxal product, and −0.270 V and −0.447 V for the biacetyl product respectively, at pH=1.5), or a single well-defined reduction wave corresponding to a two-electron transfer at pH values above 3 (E1⁄2:−0.831 V and −0.902 V respectively, at pH=9.0). At pH values below 8, it has also been observed that the reduction product with the two-electron wave shows an ill-defined reduction wave (E1⁄2:−1.15 V and −1.07 V respectively, at pH=5.0) at a little more positive potential than that of the hydrogen ion discharge. During the course of the controlled-potential electrolysis at −1.0 V vs. SCE at a pH value of about 9, it has been observed that the anodic wave of the reduction product with the same half-wave potential as the above reduction wave grows at the expense of the reduction wave (probably because of the quinoxaline formed by the condensation), while, though the reduction wave decreases with the electrolysis at −0.7 V, no anodic wave due to the oxidation of the electrolytic reduction product is obtained at pH values lower than 6. A linear relationship between the limiting current of the condensation product and the concentration (0.5–20×10−4m) of methylglyoxal or biacetyl has been obtained under the following conditions, which are recommended for the practical determination: 3–10 for pH, (1–2)×10−2m for the concentration of OPD, 25°C for the temperature, and 20–60 min for the condensation time. The method was also used to determine the purity of a methylglyoxal prepared in the laboratory and that of a commercial biacetyl.
The Polarographic Behavior of the Condensation Products of o-Phenylenediamine with Glycolaldehyde and with Glyceraldehyde, and Its Application to the Determination of Glycolaldehyde and Glyceraldehyde
Authors: Wasa Tamotsu , Musha Sôichirô
Published: July 2006

Glycolaldehyde and glyceraldehyde condense with o-phenylenediamine (OPD) in a buffered solution (pH 2–10) containing an excess of the latter to produce the corresponding condensation products. Both condensation products give a single diffusion-controlled oxidation wave E1⁄2:−0.08 V vs. SCE for both aldehydes at pH 6.0) at the dropping mercury electrode, and their electrode reactions are irreversible over all the pH range studied (pH 2—10). The limiting currents of both waves show their maximum values at pH values of about 6 and decrease either with an increase or a decrease in the pH from about 6. From the results of the present polarographic investigations, it has been deduced that the condensation products of OPD with glycolaldehyde and with glyceraldehyde are probably benzimidazoline derivatives. The equilibrium constants for the condensation reaction of glycolaldehyde and glyceraldehyde with OPD were calculated to be 551 and 294 l/mol respectively at 25°C. A linear relationship between the limiting current of the condensation product and the concentration [(0.5–30)×10−4m] of glycolaldehyde or glyceraldehyde was obtained under the following conditions, which are recommended for the practical determination: 5.5–6.5 for pH, 2×10−2m for the concentration of OPD, 25°C for the temperature, and 5–60 min for the condensation time. The present method was applied to the determination of the glycolaldehyde present as an impurity in a commercially-available ethylene glycol.
Cholestanol Esters of Amino Acids
Authors: Matsumoto Yoshio , Shirai Michiko , Minagawa Michio
Published: July 2006

The cholestanol (5α-cholestan-3β-ol) esters of amino acids were synthesized with an interest for their possible biochemical activities. The cholestanol esters of glycine, l-alanine, β-alanine, l-leucine and l-aspartic acid were synthesized by a direct fusion of the two components under the passing of hydrogen chloride through the reactants. That of glutamic acid was prepared by using quinoline hydrochloride as a solvent. From the condensation product of aspartic acid and cholestanol, mono- and di-ester were isolated. The monocholestanol ester of aspartic acid was also synthesized by the Gabriel process.
Studies on Hydrogenation Reactions with Metal Sulfide Catalysts. III. Hydrogenation and Isomerization of Cyclohexene
Authors: Hai Chang King
Published: July 2006

The catalytic liquid phase hydrogenation and/or isomerization of cyclohexene are investigated at 160–350°C under 50–90 kg/cm2 of hydrogen or atmospheric nitrogen using molybdenum trisulfide and various other metal sulfides or oxides, with or without additives, as catalysts. The activity of catalysts is found to be in the order of MoS3≥MoS2>WS3>CoS3>NiS2. The hydrogenation product is almost entirely cyclohexane, except when molybdenum trisulfide is used as a catalyst, in which case the reaction at 310°C accompanies isomerization to a considerable extent, yielding up to 24% of methylcyclopentane. The molybdenum disulfide catalyst with the addition of sulfur or hydrogen sulfide is similar to the molybdenum trisulfide in its selectivity for the course of reaction. The reason for these results is discussed. The main isomerization reaction path is found to be cyclohexene → methylcyclopentene-(1) → methylcyclopentane.
γ-Ray Induced Telomerization Reactions between Allylic Compounds and Carbon Tetrachloride. IV. Reactions of Acetates of Methyl-substituted Allylic Alcohols
Authors: Okubo Masao
Published: July 2006

The γ-ray induced telomerization of allyl, α-methallyl, α,α-dimethylallyl, and β-methallyl acetates with carbon tetrachloride was carried out in order to compare the effects of methyl substituents. In the cases of the former three acetates, the effect of successive methyl substitution on the allylic α-position was found to show exactly the same regularity as to the effects on the velocities of C=C consumption, the telomer production ratios, and their change with the initial concentration of esters. In contrast with the case of α-substitution, while the β-methyl substituent retards the velocity of the C=C consumption to the utmost extent, it retards the telomer production ratio only a little; moreover, it depresses the effect of the ester concentration upon the former to some extent, but it minimizes that upon the latter. Together with these observations, the amounts of hydrogen chloride generated during irradiation was discussed in relation to the degradative chain transfer mechanism.
Studies of Peptide Antibiotics. IX. Synthesis of cyclo-(l-Valyl-l-ornithyl-l-leucyl-d-phenylalanyl-glycyl)
Authors: Aoyagi Haruhiko , Kondo Michio , Kato Tetsuo , Makisumi Satoru , Izumiya Nobuo
Published: July 2006

It was previously observed that the cyclization reaction of l-valyl-δ-benzyloxycarbonyl-l-ornithyl-l-leucyl-d-phenylalanyl-glycine p-nitrophenyl ester in pyridine yields a large amount of the pyridine-insoluble product (IV), besides a small amount of the protected cyclic decapeptide by the dimerization. By the molecular weight determination of IV with a osmometer, it was proved that the product IV is the protected cyclic pentapeptide. Hydrogenolysis of IV in a mixture of acetic acid and dimethylformamide gave cyclo-(valyl-ornithyl-leucyl-d-phenylalanyl-glycyl) acetate which showed no antibacterial activity in relation to any of the microorganisms tested.

(Remark: Graphics omitted.)
The Spectra of the Chemiluminescence, Fluorescence and Absorption of Lucigenin and Its Electron Spin Resonance
Authors: Maeda Koko , Hayashi Taro
Published: July 2006

In order to study the mechanism of the chemiluminescence of lucigenin which was emitted with hydrogen peroxide in an alkaline solution, the color and the spectrum of the chemiluminescence and fluorescence, the spectrum of absorption, and the electron spin resonance were investigated. The color of the chemiluminescence was found to vary from green to blue with a decrease in the concentration of lucigenin. The spectrum of the blue chemiluminescence spread over only a visible region of 420—650 m/μ, with a peak at 485 mμ. With an increase in the concentration of lucigenin, the peak shifted to 510 m/μ or longer, corresponding to the green color of the chemiluminescence. This shift is due to self-absorption by lucigenin. The fluorescence spectrum of lucigenin in aqueous sodium hydroxide showed a peak at 508 mμ. The peak gradually disappeared, and the spectrum eventually showed new peaks at 435 and 450 m/μ which almost agreed with the peaks of the fluorescence spectrum of 10-methylacridone. Lucigenin exhibited an electron spin resonance of a single peak (g-value 2.004) in a solid state. These results show that the chemiluminescence of lucigenin is neither of the fluorescence of lucigenin nor that of 10-methylacridone yielded in the chemiluminescent solution of lucigenin and that the mechanism of the chemiluminescence is likely to involve a free radical intermediate.
Some 4(1H)-Pyridylidene Compounds. Synthesis and Structure
Authors: Omote Yoshimori , Kuo Kung-Tu , Sugiyama Noboru
Published: July 2006

The reaction of methyl 4-chloro-pyridine-2,6-dicarboxylate with a sodium compound of t-butyl cyanoacetate, ethyl cyanoacetate, or malononitrile, followed by acidification, gives the corresponding 4(1H)-pyridylidene compound, t-butyl cyano-4(1H)-(2,6-bismethoxy-carbonyl-pyridylidene)-acetate (IVa), ethyl cyano-4(1H)-2,6-bismethoxycarbonyl-pyridylidene) acetate (Va), or 4(1H)-(2,6-bismethoxy-carbonyl-pyridylidene)malononitrile (Via). The structures assigned to these compounds are based on the UV, IR and NMR spectra. In an alkaline solution, IVa, Va and Via change into the anion forms. The elimination reaction of IVa and Va is also examined.
Studies on Amino-hexoses. XIII. The Synthesis of Methyl 4′,6′-O-Ethylidene-β-pseudocellobiouronoside Methyl Ester, and Its Degradation with Hydrazine
Authors: Fujinaga Mamoru , Matsushima Yoshio
Published: July 2006

A derivative of pseudocellobiouronic acid, methyl 4′,6′-O-ethylidene-β-pseudocellobiouronoside methyl ester was prepared and subjected to the treatment with hydrated or anhydrous hydrazine. Both of hydrated and anhydrous hydrazine have been found to cause the glycosidic cleavage, the extent of which has been estimated by measuring the amount of 4′,6′-O-ethylidene-d-glucose formed by a gas-liquid partition chromatography. The results obtained suggest that the polysaccharides which contain 1→4 glycosidic bonds to the uronic acids are degraded by the hydrazine treatment, conceivably due to β-elimination reaction.
Verification of Bhattacharya’s Equation for Slow Coagulation by Spectrophotometric Measurements in Copper Ferrocyanide and Zinc Ferrocyanide Sols
Authors: Chaturvedi D N , Bansal O P
Published: July 2006

The copper ferrocyanide and zinc ferrocyanide sols have been prepared, and their precipitation values have been studied by using KCl, BaCl2 and AlCl3 and by employing the spectrophotometric method in the light of the equation:

C=a+\fracm·1⁄tn+1⁄t

It has been found that the values of a and m remain the same at all stages of coagulation, while the value of n depends to a great extent on the coagulation stage.
The Photochemistry of Aqueous Hexacyanoferrate(II) Solutions. II. Photo-oxidation Reaction at 2537Å
Authors: Ohno Shin-ichi
Published: July 2006

The effects of 2537 Å radiation upon solutions of hexacyanoferrate(II) were investigated at 25°C, using specific scavengers for hydrated electrons (N2O, H3O + , and NO3−) and for hydrogen atoms (CH3OH and C2H5OH). In the presence of N2O or NO3−, a photo-oxidation reaction giving hexacyanoferrate(III) was found to take place, the primary process being:

[Fe(CN)6]4−\xrightarrowhν[Fe(CN)6]3−+e−aq

The quantum yield of this photochemical process was determined to be 0.35 at 25°C. The e−aq thus formed reacted with N2O, NO3−, and H3O+ , just like the hydrated electron produced in water irradiated with fast electrons or γ-rays.
The Photochemistry of Aqueous Hexacyanoferrate(II) Solutions. III. The Effect of Acetone on the Photo-oxidation Reaction at 2537 Å
Authors: Ohno Shin-ichi
Published: July 2006

The photochemistry of the hexacyanoferrate(II) ion was investigated at 2537Å in the presence of acetone and of N2O or NO3−. Acetone was found to act as a scavenger for the photo-chemically-produced electron, thus giving an acetone radical which can reduce the hexacyanoferrate(III) ion to the -(II) ion. The relative reaction rates of the electron, k(e−aq+acetone)/ k(e−aq+N2O) and k(e−aq+ acetone)/k(e−aq+NO3−), were found to be 1.5 and 0.45 respectively. These rate ratios were found to vary with the ionic strength value in a way which indicates that e−eq has a unit negative charge and survives long enough for the establishment of its ionic atmosphere.
The Photochemistry of Aqueous Hexacyanoferrate(II) Solutions. IV. A Study of the Mechanism of the Photoelectron Detachment
Authors: Ohno Shin-ichi
Published: July 2006

The effects of environmental changes, such as temperature changes, the addition of salts, and the use of D2O as a solvent, upon the absorption spectrum of the hexacyanoferrate(II) ion, as well as upon the photochemical yield of hydrated electrons, have been investigated. The results observed have then been tentatively interpreted in terms of a proposed mechanism: (1) the absorption of light quanta results in an “internal” metal-(d)→ CN-(π*) excited state; (2) the rate of the detachment of an electron from this excited state to the solvent is dependent on the size of the cavity occupied by the complex ion surrounded by the hydration layers of the water, and (3) environmental changes affect the size of the cavity, thus influencing the magnitude of the quantum yields of e−ap.
The Crystal Structure of the 1 : 1 Complex N, N, N′ N′-Tetramethyl-p-phenylenediamine and 1,2,4,5-Tetracyanobenzene
Authors: Ohashi Yuji , Iwasaki Hitoshi , Saito Yoshihiko
Published: July 2006

The crystal structure of the 1 : 1 complex formed between N, N, N′ N′-tetramethyl-P-phenylenediamine and 1,2,4,5-tetracyanobenzene has been determined by X-rays at room temperature. The crystals are triclinic with one formula unit of the complex in a cell of dimensions: a=7.654 Å, b=8.041 Å, c=7.462 Å, α=96.7°, β=85.9° and γ=101.3°. The space group is P\bar1. The structure has been solved by three-dimensional Fourier and least-squares methods. The component molecules are stacked alternately in infinite columns along the c-axis. The structure does not seem to show the usual π–π interaction between the two aromatic rings, but indicates the n–π interaction localized between the nitrogen atoms of the donor and the cyano groups of the acceptor. From the direct integration of the electron density, the quantity of the charge transfer from the donor to the acceptor has been estimated to be 0.24 in electron units.
Radiation Chemistry of Dicarboxylic Acids in the Solid State. I. Radiolysis of Malonic Acid in the Solid State
Authors: Hosaka Akio , Sugimori Akira , Genka Tsuguo , Tsuchihashi Gen-ichi
Published: July 2006

The radiolysis of solid malonic acid by 60Co γ-rays has been studied in vacuo at −196°C, − 78°C, and room temperature. All the products were measured after dissolving the irradiated malonic acid in water. The main products were carbon dioxide with G=4.4 and acetic acid with (G=4.5, as was determined by the reverse isotope dilution analysis. The yields of the other products (hydrogen, carbon monoxide, methane, ethane and carbonyl compounds) were very low. These facts revealed that the following reaction takes place selectively:

(Remark: Graphics omitted.)

The mechanism of the reaction is discussed with reference to the results of product analyses and ESR.
Nickel(II) Complexes of Schiff Bases Derived from Alkanolamines and Salicylaldehyde and 3-Methoxysalicylaldehyde
Authors: Yamada Shoichiro , Kuge Yoshio , Yamanouchi Kuniko
Published: July 2006

Nickel(II) complexes of Schiff bases derived from salicylaldehyde and amines have so far been studied. In the present work, the nickel(II) complexes of N-hydroxyalkyl-salicylideneimines and related compounds are taken up, and the behavior of the hydroxyl group as to its coordination with the nickel(II) ion is examined. Bis(N-hydroxyalky 1-3-methoxysalicylideneiminato)-and bis(N-hydroxyalkyl-salicylideneiminato)-nickel(II) complexes have been prepared in the present work, where R=CH2CH2OH, CH2CH(CH3)OH, C(CH3)2CH2OH and CH2CH2CH2·OCH3. These complexes, except for the complexes with R=CH2CH2CH2OCH3, in the solid state are hexa-coordinated and show paramagnetism corresponding to two unpaired electrons. They are hexa-coordinated in non-donor solvents, except for the nickel(II) complexes with R=C(CH3)2CH2OH, which take a hexa-coordinated configuration in ethanol or methanol, a square-planar configuration in chloroform, and a different configuration in pyridine.
Study of Dielectric Relaxation Mechanism in Some Substituted Pyridines
Authors: Mehrotra N K , Saxena M C
Published: July 2006

The relaxation times of 2-chloro-, 2-bromo-, 3-bromo-, 2-methyl-, 2-acetyl- and 2-hydroxy-pyridines have been determined in the 3 cm microwave region at 20°C using benzene as solvent. It has been concluded from the relaxation times of 2-chloro-, 2-bromo-, 3-bromo- and 2-methylpyridines that these rigid molecules relax predominantly by the process of over-all molecular rotation. The comparatively small relaxation times of 2-acetyl- and 2-hydroxypyridines suggest that these non-rigid molecules relax by both molecular as well as intramolecular rotations. The free energies of activation for dipole orientation for the compounds investigated are always found to be smaller than those for viscous flow, because the process of dipole orientation involves only rotation, while the process of viscous flow involves both rotation and translation.
Kinetic Studies of Bimolecular Nucleophilic Substitution. III. Rates of SN2 and E2 Reactions of ω-Chloroalkylbenzenes with Sodium Acetate in 50 vol% Aqueous Acetone—Alternation Effects in Saturated Carbon Chains
Authors: Okamoto Kunio , Kita Teruo , Shingu Haruo
Published: July 2006

The rate of the bimolecular reactions of a series of ω-chloroalkylbenzenes, C6H5(CH2)nCl(n=1–4), with sodium acetate have been measured in 50 vol% aqueous acetone in the range from 100 to 130°C. The second-order rate constants, k2, have been obtained by measuring the rate of chloride-ion liberation. From the k2 values, i. e., kSN2+kE2, and the olefin percentage in the products, which was determined by measuring the rate of acetic acid formation, the SN2 rate constant, kSN2, and the E2 rate constant, kE2, for each chloride have been calculated. For purposes of comparison, the kSN2 and kE2 values for n-alkyl chlorides, CnH2n+1Cl (n=1–4), in the same solvent at 120°C have been calculated by a similar treatment of the rate in the bimolecular reactions of titled chlorides with sodium acetate. There is an alternation effect on the SN2-rate sequence of the ω-chloroalkylbenzenes, whereas no alternation effect has been observed for the E2 reactions of ω-chloroalkylbenzenes or for the SN2 and the E2 reactions of n-alkyl chlorides. From an examination of these data, together with the results previously reported in the literature, the zigzagging of the rate sequence in the SN2 reactions of ω-substituted alkyl halides has been thought most probably to originate from steric effects. In contrast to the previous observation in the E2 reactions of alkyl bromides with sodium ethoxide, the rate sequence for alkyl chlorides with sodium acetate has been found to be governed by the Hofmann rule.
Kinetic Studies of Bimolecular Nucleophilic Substitution. V. Rates of SN2 and E2 Reactions of 1,2-Dichloroethane with Various Nucleophiles in Aqueous Solutions
Authors: Okamoto Kunio , Matsuda Hisayuki , Kawasaki Hiroshi , Shingu Haruo
Published: July 2006

The rates of the reactions of 1, 2-dichloroethane with sodium hydroxide, sodium phenoxide, trimethylamine, pyridine, and sodium acetate have been measured in aqueous solutions at 110 and 120°C. On the assumption that the substitution reaction of 1, 2-dichloroethane produces two equivalents of the chloride ion because of the greater reactivity of the mono-substitution products (β-substituted ethyl chlorides) than that of the starting substrate, while the elimination product from 1, 2-dichloroethane, i. e., vinyl chloride, does not react with the bases under the reaction conditions employed, the kSN2 and kE2 have been calculated from the rate of the chloride-ion liberation and from the number of moles of the base required to react with one mole of the substrate. For a series of kSN2 values there is no linear relation between the rates and the pKa’s of the conjugate acids, whereas a parallelism exists between the kE2 and the pKa. The stronger the base, the more the elimination is promoted.
Aminocyclitols. XIII. Studies on the Synthesis of Streptamine
Authors: Suami Tetsuo , Ogawa Seiichiro
Published: July 2006

Starting from epi-inositol, two new inosamines: epi-l and epi-6, and two inosadiamines: myo-4, 6 and streptamine, have been prepared by a replacement of sulfonate group by an azide ion. The nuclear magnetic resonance spectroscopy has established the configurations of the products.
The Activity of a Catalyst from Nickel Chloride and Methyl-hydropolysiloxane in the Hydrogenation of Olefins
Authors: Takegami Yoshinobu , Ueno Toru , Masunaga Kunihiko
Published: July 2006

The reaction of anhydrous nickel(II) chloride with methylhydropolysiloxane has been found to give an active catalyst for the hydrogenation of olefins. These two reagents react readily at 120–170°C, with the evolution of hydrogen, to form a black-colored substance which has been used as the catalyst. The catalytic activity has been found to depend on the amount of hydrogen evolved during the reaction and on the methylhydropolysiloxane : nickel chloride ratio. The most active catalyst has been obtained by using the reagents in the Si : Ni ratio of 25 : 1 and by intercepting the reaction as soon as the hydrogen evolution amounted to 1.0 mol per mole of nickel chloride. Cyclohexane has been successfully used as a solvent. However, the presence of diethyl ether or tetrahydrofuran has considerably deactivated the catalyst. The catalyst deactivated by ether has, though, been highly activated by adding a large excess of water.
The Ionic Telomerization of Conjugated Diene Compounds. II. The Solvent Effects on the Cationic Telomerization of Butadiene with Its Hydrochloride
Authors: Asahara Teruzo , Kise Hideo
Published: July 2006

The telomerizations of butadiene with its hydrochlorides (1-chlorobutene-2 and 3-chlorobutene-1) in several sorts of solvents in the presence of Lewis acids were investigated. Titanium tetrachloride in ethyl bromide has a considerable catalytic ability at low temperatures and gives telomers with higher average molecular weights than ferric chloride and aluminum chloride at almost the same conversions of reaction. On the other hand, antimony pentachloride gives only a small amount of product with lower average molecular weights. The telomerizations in methylene dichloride and chloroform give almost the same amounts of telomers with molecular weights higher somewhat in the former solvent than the latter. The telomerization in toluene gives primarily the products of Friedel-Crafts reaction, and a small amount of telomers of butadiene with crotyl chloride is obtained. The use of ethyl ether, acetonitrile and acetic anhydride as solvents at low temperatures in the presence of ferric chloride affords poor yields of the telomers in contrast to the cases of halogenated hydrocarbons. In ethyl ether, an appreciable amount of telomers is obtained only at the temperatures above 0°C. The telomers thus obtained have a lower average molecular weight and a larger degree of residual unsaturation than the telomers obtained in halogenated hydrocarbons. The use of nitromethane and nitrobenzene as solvents leads to the formation of an amount of telomers smaller a little than halogenated hydrocarbons. There are scarcely observed differences in the compositions of fractions in 1 : 1 adducts of butadiene and its hydrochloride obtained in the various solvents. The infrared spectra of the higher telomers are almost the same each other and it was concluded that the reactions proceed on the same mechanism irrespective of the variation of solvents.
Amide Mercaptole. II. The Reactions of N, N-Dimethylbenzamide Diethylmercaptole with Some Heavy Metal Compounds
Authors: Yamaguchi Tatsuaki , Mukaiyama Teruaki
Published: July 2006

The reactions of N, N -dimethylbenzamide diethylmercaptole with mercuric compounds (mercuric oxide, mercuric acetate and mercuric cyanide) or lead(IV) compounds (lead dioxide and lead tetraacetate) have been investigated. Mercuric acetate was found to react easily with the amide mercaptole giving N, N-dimethylbenzamide and acetic anhydride with the elimination of mercury ethylmercaptide. In a similar way, mercuric cyanide gave α-dimethylamino phenylmalononitrile in a good yield. Further, it was shown that the amide mercaptole was oxidized by lead dioxide or lead tetraacetate to N, N-dimethylbenzamide and diethyl disulfide. The high reactivity of the amide mercaptole toward heavy metal compounds was discussed in comparison with common mercaptals.
Studies of Peptide Antibiotics. XL Analogs of Gramicidin S and Cyclosemigramicidin S Containing Glycine or Alanine in Place of Valine
Authors: Kondo Michio , Izumiya Nobuo
Published: July 2006

To investigate the contribution for the antibacterial activity of the valine residues in a gramicidin S molecule, two analogs of gramicidin S, 1, 1′-glycine- and 1, 1′-l-alanine-gramicidin S, were prepared through the cyclization reaction of linear decapeptide active esters in pyridine. 1-Glycine- and 1-l-alanine-cyclosemigramicidin S were also prepared through the cyclization of linear pentapeptide active esters. The effects of the four cyclic peptides thus obtained on bacterial growth were tested; only 1, 1′-alanine-gramicidin S was as active as natural gramicidin S, while the other three analogs showed no activity in relation to any of the microorganisms tested. The results indicate that the side chains of the valines in gramicidin S can be replaced by smaller aliphatic side chains, the methyls, without the influence for the activity.
The Crystal Structure of the Perylene-Tetracyanoethylene Complex
Authors: Ikemoto Isao , Kuroda Haruo
Published: July 2006

The crystal structure of the perylene-tetracyanoethylene (TCNE) complex has been determined by the two-dimensional Fourier synthesis and by difference synthesis. The monoclinic unit cell dimensions are: a=15.79, b=8.28, c=7.31 Å, and β=96.1°. Two perylene and two TCNE molecules are in a unit cell. The space group is P21⁄a. Perylene and TCNE molecules are stacked alternately along the b-axis, making their molecular planes parallel to each other. The center of a TCNE molecule is not directly above that of the neighboring perylene molecule. The mean separation of the molecular planes is 3.23 Å.
Generation of Free Radicals at Subzero Temperatures. I. Methanolyses of Thionyl Chloride and Methyl Chlorosulfite
Authors: Minato Hiroshi , Fujii Atsushi
Published: July 2006

Rates of methanolysis of thionyl chloride and methyl chlorosulfite were measured conductimetrically at +1.0–−91.6°C, and were compared with the rates of other acid chlorides. Activation enthalpies and entropies were obtained.
Proton Magnetic Resonance Study of Solid Hexamethylethane
Authors: Koide Tsutomu
Published: July 2006

The molecular motion of solid hexamethylethane was studied by the proton magnetic resonance method from the liquid nitrogen temperature to 20°C. In the temperature range between about −160°C and −120°C, the methyl group rotates about its own axis, and also the molecule rotates about the molecular axis as a whole. Above −120°C, the molecule rotates almost freely. On the other hand, the molecular motion of hexamethyldisilane in the high temperature phase has been explained in terms of the facts that the molecule rotates freely and also has a degree of translational freedom. The difference in the molecular motion between hexamethylethane and hexamethyldisilane is caused mainly by the difference in the molecular interaction.
Studies of the Solvent Effects on the Chemical Shifts in NMR Spectroscopy. III. The Benzene Solutions of Cyclic Ketones and Lactones
Authors: Ichikawa Yukihiko , Matsuo Taku
Published: July 2006

The high-field shifts of the proton signals of cyclic ketones and lactones in the benzene solutions have been investigated. The solvent effects on the chemical shifts for the β-methylene protons of these compounds are always larger than those for the α-methylene protons. The data may be explained by the use of a model in which benzene molecules are assumed to cluster around the carbonyl group of the solute. The affinity between the solute and the solvent molecules has been mainly ascribed to the fact that both the permanent electric dipole moment and the instantaneous dipole moment of the carbonyl (or carboxyl) group induce electric dipole moments in the near-by benzene molecules. The configuration and the number of the solvent molecules clustering around the solute have been suggested to be determined by the geometrical restriction around the carbonyl group.
The Reactions of the OH Radical Arising from Nitrous Oxide in an Aqueous Hexacyanoferrate(II) Solution Illuminated at 2537Å
Authors: Ohno Shin-ichi
Published: July 2006

A method for the determination of the relative rate constants for reactions of the OH radical is described. The OH radical is generated from the reaction between N2O and the photochemically-produced electron in a solution of 10−3  m hexacyanoferrate(II) irradiated at 2537 Å. The method has been applied to the determination of the rate constants for the reactions of OH with methanol, ethanol, 2-propanol, formate, bromide, glycine, and boric acid relative to that with [Fe(CN)6]4−. The values found are compared with those obtained by other methods, and their significance is discussed.
Ribonuclease T1 Peptides. I. Synthesis of a Protected N-Terminal Undecapeptide Containing Asparagine Residue in Third Position
Authors: Ohno Motonori , Kato Tetsuo , Mitsuyasu Nobuo , Waki Michinori , Makisumi Satoru , Izumiya Nobuo
Published: July 2006

A protected undecapeptide containing the possible N-terminal sequence of ribonuclease T1, namely benzyloxycarbonyl-l-alanyl-S-benzyl-l-cysteinyl-l-asparaginyl-l-tyrosyl-l-threonyl-S-benzyl-l-cysteinyl-glycyl-l-seryl-l-asparaginyl-S-benzyl-l-cysteinyl-l-tyrosine ethyl ester (XXI), was synthesized by coupling of benzyloxycarbonyl-alanyl-S-benzylcysteinyl-asparaginyl-tyrosine azide with heptapeptide ester, threonyl-S-benzylcysteinyl-glycyl-seryl-asparaginyl-S-benzylcysteinyl-tyrosine ester, which is derived from p-methoxybenzyloxycarbonyl-heptapeptide ester by the action of trifluoroacetic acid. The optical homogeneity of the protected undecapeptide (XXI) was established by deblocking of XXI and subsequently digesting the resulting free undecapeptide with leucine aminopeptidase.
Radiolysis of CoIII-EDTA in Aqueous Solution; the Yields of Hydrogen and Hydrogen Peroxide in 0.8 n Sulfuric Acid
Authors: Matsuura Niro , Shinohara Nobuyoshi , Nishikawa Masaru , Takizawa Masao
Published: July 2006

The hydrogen and hydrogen peroxide produced in the radiolysis of CoIII-EDTA (CoIIIY−) in 0.8 n sulfuric acid have been measured. The yields of hydrogen and hydrogen peroxide were found to be G∞(H2)=0.4 and G∞(H2O2)=2.5 for the aerated system, G∞(H2)=3.2 and G∞(H2O2)=0 for the deaerated system where G∞ denotes the yield at the infinite solute concentration. The decomposition mechanism proposed previously was discussed in detail on the basis of the observed G∞(H2) and G∞(H2O2) and of the effect of chloride ion on the decomposition yield G∞(–CoIIIY−). A similar experiment was carried out for EDTA alone and the decomposition mechanism was discussed.
The Radiation Chemistry of Cyclic Dienes. II. The Radiolysis of 1,4-Cyclohexadiene in the Gas Phase
Authors: Nakagawa Tsunehiko , Takamuku Setsuo , Sakurai Hiroshi
Published: July 2006

The γ-radiolysis of 1,4-cyclohexadiene vapor has been investigated at room temperature. The gaseous products are hydrogen, acetylene, and 1,3-butadiene. Benzene, cyclohexene, 1,3-cyclohexadiene, and 1,3,5-hexatriene are identified as the low volatile liquid products. The yield of each product is almost independent of the dose (0.87–9.11)×1019 eV, while it is remarkably dependent on the gas pressure (8–56 mmHg). The G values of hydrogen, the C2+C4 gas fraction, benzene, and cyclohexene are 1.95, 1.25, 28.5, and 14.0 respectively at 42 mmHg. The large yields of benzene and cyclohexene may be explained in terms of a chain mechanism. The pressure dependence of these products is very similar in both the Hg-sensitized photolysis and the γ-radiolysis of this diene vapor. The presence of the long-lifetime intermediates is as expected. The experiments with nitric oxide added as a radical scavenger suggest that the main path of hydrogen formation is the radical process.
Cyanoethyl Complexes of Cobalt—Their Preparation and Their Reactions with Acrylonitrile
Authors: Misono Akira , Uchida Yasuzo , Hidai Masanobu , Kanai Hideo
Published: July 2006

By the addition reaction of acrylonitrile to hydridobis (dimethyl- or diphenylglyoximato)-pyridinecobalt, only 1-cyanoethyl complexes were obtained. The 2-cyanoethyl complex was not formed from that reaction, but from the reaction of 3-bromopropionitrile with the hydride complex. NMR spectroscopy was used to confirm the structure of the complexes. The isomerization of the 2-cyanoethyl complex to the 1-cyanoethyl complex at 70°C was not observed by NMR measurements. The reaction of these complexes with acrylonitrile was carried out under a hydrogen atmosphere. It was observed that 2-methylglutaronitrile was formed from the reaction of the 1-cyanoethyl complex with acrylonitrile. The thermal decomposition and the reaction of the complexes with hydrochloric acid were also investigated.
The Liquid Phase Oxidation of Acrolein. V. Effects of Water on the Oxidation of Acrolein
Authors: Ohkatsu Yasukazu , Osa Tetsuo , Misono Akira
Published: July 2006

Some water was added as a model to a reaction solution containing Co(acac)2 before the beginning of the reaction by two methods in order to examine the effects of water formed during the reaction. These two methods gave different phenomema in the induction periods and different oxygen absorption rates. From these results and those with Co(acac)2·2H2O, the water added is considered to act in two ways, increasing the reaction rate by the coordination with the catalyst and decreasing the reaction rate when not bonded with the catalyst. The latter effect is considered in detail on the basis of the oxygen absorption rate: −dO2/dt=k(acrolein)0.88. (catalyst)0.39(H2O)r, wherein r is −0.1 or −0.21. This rate equation accorded well with the derived rate equation considering the reaction phenomena and the interaction among the catalyst, acrolein, and water in the initiation reaction.
Photoreactions of Cyclopentenone Derivatives
Authors: Moritani Ichiro , Toshima Naoki , Nakagawa Shiro , Yakushiji Masatoshi
Published: July 2006

Photoreactions of conjugated or non-conjugated, five-membered, cyclic ketones were investigated. Irradiation of 2,3,4,5-tetraphenyl-2-cyclopenten-1-one in 2-propanol with ultraviolet light under a slow stream of nitrogen or oxygen gave 1-oxo-2,3-diphenyl-2,3-dihydro-1H-cyclopenta[l]phenanthrene (55%) and 1-oxo-3-hydroxy-2,3-diphenyl-2,3-dihydro-1H-cyclopenta[l]phenanthrene (about 20%). Similar irradiation of 3,4-diphenyl-3-cyclopenten-1-one under a nitrogen stream gave 2-oxo- and 2-hydroxy-2,3-dihydro-1H-cyclopenta[l]phenanthrene in 33% and 11% yields respectively. In both cases, there was observed photocyclization of a cis-stilbene skeleton to a phenanthrene. However, on irradiation of 2,2-dimethyl-3,4-diphenyl-3-cyclopenten-1-one, there was obtained a decarbonylation product, 1,1-dimethyl-1,2-dihydrocyclobuta[l] phenanthrene. The reaction courses of these photoreactions are proposed.
Über die Umsetzung eines Ketenimins mit Cyanessigester und Malonester
Authors: Ichimura Kunihiro , Ohta Masaki
Published: July 2006

The reaction of either N-(p-chlorophenyl)diphenylketenimine or N-(p-chlorophenyl)diphenylacetimidoyl chloride with ethyl cyanoacetate gave the identical α, β-unsaturated ester. Whilst the reaction of the ketenimine with diethyl malonate yielded β, γ-unsaturated diester, the isomeric α, β-unsaturated diester was obtained by the reaction of the imidoyl chloride with the malonate. These remarkable different phenomena could be ascribed to the difference in bulk between cyano and carbethoxy groups. The structures of these products were discussed on the basis of the infrared and ultraviolet spectroscopic data and the reaction mechanisms were proposed. Additionally, the pyrolysis of the products was studied and the β, γ-unsaturated diester was found to give quinolin-4-one together with an α-naphthol derivative under elimination of ethanol, whilst only quinolin-4-one was isolated on the pyrolysis of the isomeric α, β-unsaturated diester.
A Structural Study of Di-O-isopropyridene-pentitols by Conversion to the Corresponding Mono-O-benzyl Derivatives
Authors: Nakagawa Toshio , Tokuoka Hisao , Shinoto Kazuhiko , Yoshimura Juji , Sato Tetsuo
Published: July 2006

d-Arabinitol and xylitol were acetonated, benzylated and then hydrolyzed with a mineral acid to afford in good yields the corresponding 1-O-benzyl derivatives, which were identified by a periodate oxidation and a chemical identification. A preferential acetonation of the pentitols is discussed in a view of stereochemistry. Synthesis of 2-O-benzyl-d-arabinitol and 3-O-benzylxylitol are also described.