bluuebunny/crossref_metadata_2025 huggingface dataset:
The Synthesis of Cyclic α-Amino Acids. II
Authors: Kinoshita Mitsuhiro , Yanagisawa Hiroaki , Doi Shuhei , Kaji Eisuke , Umezawa Sumio
Published: July 2006

The reaction of substituted derivatives of α-nitrocinnamates bearing a nitro group or a chlorine atom at the p- or m-position with cyclopentadiene produced corresponding cyclic α-nitro esters(adducts) in a good yields. The reaction of ethyl α-nitrocrotonate with cyclohexadiene gave ethyl 3-methyl-2-nitrobicyclo[2.2.2]-5-octene-2-carboxylate. In the case of an adduct, ethyl 2-nitro-3-(p-nitrophenyl)bicyclo[2.2.1]-5-heptene-2-carboxylate, there could be isolated four diastereoisomers as crystalline forms by column chromatography and fractional recrystallization. The stereochemistry of the four isomeric adducts were established by NMR spectroscopy. The readily available three of those isomers were converted to corresponding pure isomers of amino acids by reduction followed by hydrolysis. From the other adducts the major amino acid isomers or the amino acid mixtures were obtained in an analogous route.
Intramolecular Interaction between the Hydroxyl Group and the Cyclopropane Ring
Authors: Oki Michinori , Iwamura Hiizu , Murayama Tetsuo , Oka Isao
Published: July 2006

Cyclopropylcarbinol shows two absorption maxima due to the O–H stretching, the lowerfrequency band being stronger than the higher. The results are interpreted on the basis of intramolecular interaction between the hydroxyl group and the cyclopropane ring. This kind of interaction is not clearly detected with 2-cyclopropylethanol, but 2,2-dicyclopropylethanol and 2-(1-methylcyclopropyl)ethanol give results which are best interpreted by assuming the presence of the interaction. It is concluded, from the findings on rigid molecules, that O–H···cyclopropane interaction is possible when the hydroxyl group approaches the edge within the plane of the ring. The steric effect of the methyl group is also discussed.
Photolysis of Nitrosobenzene
Authors: Tanikaga Rikuhei
Published: July 2006

The mechanism of the photochemical reaction of nitrosobenzene (I) has been investigated. The irradiation of I leads to the formation of a phenyl radical and nitric oxide. The reaction of the phenyl radical with I yields diphenylnitroxide, which is then easily reduced to diphenylamine. The reaction of diphenylamine with the nitric oxide gives C-nitrosodiphenylamines, which are then photochemically oxidized to C-nitrodiphenylamines. On the other hand, I is oxidized to nitrobenzene and is, at the same time, reduced to azoxybenzene and azobenzene. Azoxybenzene is photochemically rearranged to 2-hydroxyazobenzene.
Ignition Delay Time Studies of Hydrogen and Oxygen Reactions through Silent Electric Discharge
Authors: Morinaga Kihei
Published: July 2006

The ignition of hydrogen and oxygen could be induced by the so-called silent electric discharge, and the ignition delay time after the termination of the discharge was found to be proportional to a logarithm of the discharge intensity (pulse current). The proportionality constants in different diluents, argon and helium, were analyzed to yield the net effect of chain breaking in the reaction:

H+O2+M\xrightarrowk4HO2+M

and the rate coefficient, k1, for the reaction:

H+O2\xrightarrowk1OH+O

assuming a third-body efficiency of the diluent gases. It was inferred from the results that the radical reproducing from HO2 significantly lessened the effect of the above chain breaking reaction, the accumulation of radicals seemed to be persistent even in the low-temperature region, where the k1 value was observed not to be above the assumed value of k1[M]/2.
Some Observations on Photolysis of Fused Cyclopentyl Nitrites
Authors: Suginome Hiroshi , Sato Norio , Masamune Tadashi
Published: July 2006

The results of photolysis of three fused cyclopentyl nitrites, Ib, VIIIb, XIV, all of which have 22,27-imino-17,23-oxidojervane framework, are described. In all three cases, competition among the reactions of 11-alkoxyl radical, which led to a variety of products, has been observed. However, the cleavage of α,β carbon-carbon bond to the nitrosoxyl group in these compounds is not the major course of the reaction. It has been found that whenever sterically possible (e. g., Ib), 11-alkoxyl radical in these nitrites is capable of achieving the Barton reaction and the reaction leads to relatively few products. In two cases of these photolyses, the reaction is accompanied by epimerization of the relevant alkoxyl radicals. Some aspects of these transformations are considered in the light of other available data.
Orbital Electronegativities in Molecules and Ionic Character in Molecular Complexes
Authors: Matsunaga Yoshio
Published: July 2006

The orbital electronegativities in the nine aromatic hydrocarbons were estimated on the basis of the ionization potentials and the appearance potentials of the doubly-charged ions. Then, by applying the principle of electronegativity equalization to molecular complexes, the orbital electronegativities in typical electron acceptors were evaluated. The ionic character in single and crystal complexes were discussed in terms of the electronegativities of the component molecules. Consideration of neither the ionization potential of the donor molecule, the electron affinity of the acceptor molecule, nor the orbital electronegativities appeared to be enough to define the ionic character in a complex.
Heat of Immersion of Titanium Dioxide in Water. II. The Effect of the Crystallinity of Anatase
Authors: Omori Teiji , Imai Junichiro , Nagao Mahiko , Morimoto Tetsuo
Published: July 2006

Two kinds of anatase samples which have very large specific surface areas and low crystallinities were prepared, and the interaction between the solid surface and the water molecule was investigated by measuring the water content, the heat of immersion in water, and the infrared spectrum of each sample. Two characteristic features were found in these samples: first, the plot of the heat of immersion vs. the pretreatment temperature did not reveal such a maximum as had been found previously with the crystalline anatase, and second, the heat of surface hydration as calculated from the plot of the heat of immersion vs. the water content was found to be remarkably smaller than with the crystalline anatase. These facts have led us to conclude that, with the anatase samples of a low crystallinity, not only does the rehydration reaction of a surface oxide structure produced at an elevated temperature proceed more easily on immersion in water, but also the heat of rehydration is smaller, than in a sample of a high crystallinity. Moreover, it was found from an infrared spectroscopic investigation that the water molecules physisorbed on the surfaces of large-area samples could be desorbed more gradually than those on small-area samples and remained small in quantity up to near 300°C in  vacuo.
A Study of the Low-temperature Oxidation of Cumene in the Presence of Triphenylsulfonium Chloride. Propagation and Termination Steps
Authors: Ohkubo Katsutoshi , Yamabe Tokio , Fukui Kenichi
Published: July 2006

The low-temperature liquid-phase oxidation of cumene using triphenylsulfonium chloride was-studied in order to establish the nature of the activity of sulfonium catalysts and the oxidation mechanism. The oxidation occurs in an autocatalytic fashion below 70°C, while it proceeds in an-auto-retarding fashion above 85°C. This is a characteristic feature of this oxidation. The cause of the deactivation at higher temperatures is mainly the deoxygenation of the assumed complex (Cat.···O2). The decomposition of cumene hydroperoxide and the subsequent formation of α-cumyl alcohol, acetophenone, and dicumyl peroxide were seriously affected by the presence of sulfonium salts. The formation of acetophenone was accelerated thermally, while that of a-cumyl alcohol was not accelerated much, though it was accelerated by the catalyst-oxygen complex. Dicumyl peroxide, once formed in an appreciable amount, was gradually decomposed, both thermally and catalytically. The catalyst was deactivated by the product formed. This phenomenon was attributed to the masking action of oxygen-containing products. The mechanism oxidation was discussed on the basis of these observations.
The Reaction between Mercury(II) and Organic Compounds. VII. The Formation Constant and Analytical Application of the o-(2-Thiazolylazo)-4-chlorophenol-Mercury(II) Complex
Authors: Kai Fumiaki
Published: July 2006

The formation constants of the complex formed between o-(2-thiazolylazo)-4-chlorophenol TACL, and mercury(II) in 2% v/v dioxane-water were logKHgR+=6.21 and logKHgR2=6.10 at μ=0.1 and at room temperature. TACL was suggested as a suitable metallochromic indicator for the direct titrimetric determination of mercury(II) ions at pH 6.7–8.7 with an EDTA titrant. This optimum pH range was rather wide compared with that of the other metallochromic indicators, such as Cu-PAN, XO, and MTB. There were marked colour changes from deep blue to reddish-yellow or to violet at equivalence points. The mercury(II) ions up to 210 mg in 100 ml can be determined within an error of ±0.3% by this method.
Oligomerization of Isoprene by Zirconium Catalysts
Authors: Misono Akira , Uchida Yasuzo , Furuhata Ken-ichi , Yoshida Shohei
Published: July 2006

The oligomerization of isoprene by catalyst systems consisting of a zirconium compound and an organoaluminum compound was studied. Isoprene was dimerized to 2,6-dimethyl-1,trans-3,6-octatriene by a catalyst system consisting of zirconium(IV) n-butoxide and diethylaluminum chloride. The selectivity for this dimer was increased to more than 90% by adding triphenylphosphine or tetrahydrofuran to this catalyst system. The effects of the molar ratio of the catalyst components and those of catalyst species were studied.
Synthetic Studies of 4-Oxo- and 4-Imino-3,4-dihydro-1,3-oxazoles
Authors: Chinone Akiko , Sato Shigeru , Mase Toshiyasu , Ohta Masaki
Published: July 2006

For the purpose of synthesizing new mesoionic compounds of oxazole ring system having oxo group at 4 position, reaction of N-phenylbenzimidoyl chloride with glycolic acid was examined. Only an unexpected rearranged product was obtained. The reaction of N-phenylbenzimidoyl chloride with glycolonitrile successfully afforded the intermediate, which was treated with hydrogen chloride or with picric acid or with acetyl perchlorate to give 4-imino-3,4-dihydro-1,3-oxazole derivatives. Condensation of N-phenylbenzimidoyl chloride with mandelonitrile followed by treatment with acetyl perchlorate gave 4-imino-3,4-dihydro-1,3-oxazole derivative.
Photochemical Reactions of Some Thioparabanates
Authors: Yonezawa Teijiro , Matsumoto Masakatsu , Matsumura Yoichi , Kato Hiroshi
Published: July 2006

1,3-Disubstituted thioparabanates (I) were reduced with ethanol under the action of light to yield 2-mercaptoimidazolidine-4,5-diones (II) with or without 2-(1-hydroxyethyl)-2-mercapto-imidazolidine-4,5-dione (III). It seems that these reactions may be initiated by the n–π* transition of the lone pair in the 2-thiocarbonyl group. When dimethylthioparabanate (Ic) was irradiated with a high-pressure mercury arc in a chloroform solution of amylene, a photocycloaddition product, a trimethylene sulfide (IVa), was obtained.
Studies of the Transient Intermediates of a Thiopyronine Aqueous Solution under Flash Excitation
Authors: Morita Masaharu , Kato Shunji
Published: July 2006

Flash photolytic studies of the transient intermediates produced in the flash excitation of an aqueous buffered solution of the photosensitizing dye “thiopyronine” were undertaken in order to obtain direct insight into the reaction mechanism of the photosensitizing action of the dye. As had been expected from the structural similarity to a well-known photosensitizer, methylene blue, previously reported on, the flash excitation of thiopyronine, in a deaerated buffered solution at pH 7.4 without any substrate, produced three transient intermediates: a triplet-state (Dt), a half-oxidized form (Oxd), and a half-reduced form or semiquinone (Red) of the dye. Red and Oxd were generated simultaneously through electron tansfer reactions, i.e., Dt+Dt→Red+Oxd and Dt+D→Red+Oxd, where D is the dye in the ground state. Thiopyronine solutions containing some reducing and oxidizing agents were studied in order to identify the intermediates. The absorption spectra of these intermediates were identified, and their reaction mechanism studied. The rate constants of some elementary processes obtained are:

Dt→k1=2.36×103sec−1

Dt+Dt→k′=7.69×108m−1sec−1

Dt+D→k″=7.69×108m−1sec−1

Red+Red→k6=(1–2)×109m−1sec−1

Oxd→k7=(1–3)×103sec−1

Dt+EDTA→k8=1.6×107m−1sec−1

Dt+ATU→k9≈small

Oxd+ATU→k10(2–5)×106m−1small

The high efficieny of thiopyrinine in its Photodynamic effect was discussed in connection with the high quantum yield of triplet-state production and the high reversibility of the high reversibility of the photochemical redox reaction of the dye.
Catalytic Vapor-Phase Ammoxidation of Substituted Toluenes over Chromium Oxide
Authors: Sakanishi Katsumasa , Ogata Yoshiro
Published: July 2006

Ammoxidation of substituted toluenes over a chromium oxide catalyst has been studied in a flow system at atmospheric pressure. The reactions give satisfactory yields (ca.70%) of corresponding nitriles at high conversion of toluenes. The rate constant for the reaction of substrate adsorbed on the catalyst surface, kT0, is independent of the substituent of substrate, while the adsorption equilibrium constant of gaseous substrate, KT depends on the substituent, affording Hammett’s ρ of −0.9 for σ+. These results support our mechanism reported previously for the analogous oxidation of toluene and ethylbenzene over Cr2O3, which involves an electron transfer from adsorbed hydrocarbons to dissociated oxygen.
The Bond Character of the Sn–Cl Bonds in the Hydrates of Tin (IV) Chloride
Authors: Negita Hisao , Okuda Tsutomu , Mishima Mitsuo
Published: July 2006

Several hydrates of tin(IV) chloride, e.g., SnCl4·xH2O (x=2, 3, 4 and 5) and SnCl4·yD2O (y=3, 4 and 5), were investigated by means of the nuclear quadrupole resonance (NQR) due to 35Cl and the Mössbauer effect due to 119Sn. The NQR-frequencies were observed at the temperature of liquid nitrogen and room temperature; they were found to range from 17.656 to 21.439 MHz. The Mössbauer effect was investigated only at the temperature of liquid nitrogen; it resulted in isomer shifts ranging from 0.275 to 0.350 mm/sec. The NQR-frequency and the isomer shift decreased with an increase in the number of water molecules in the hydrates, and the relationship between the NQR-frequency and the isomer shift was nearly linear. This relation was interpreted in terms of the transfer of the s-electrons of the tin atom to the chlorine atoms. Furthermore, it was revealed that there was a significant difference between the Sn-Cl bond of the hydrates and that of ammonium chlorostannate.
Palladium (II) Complexes of N-Substituted Salicylideneimines
Authors: Yamada Shoichiro , Yamanouchi Kuniko
Published: July 2006

Many new palladium(II) complexes (abbreviated as M(X-SAL·R)2) of Schiff bases obtained from substituted salicylaldehydes and alkyl and aryl amines were prepared as yellow-orange or red crystals, where X denotes H, 3-CH3O and 5,6-benzo. For R=n-alkyl and aryl groups, the complexes Pd(X-SAL·R)2 in non-donor solvents consist of square-planar molecules. The complexes of the type Pd(X-SAL·t-C4H9)2 show electronic spectra which are different from those of the complexes of the type Pd(X-SAL·n-alkyl)2, but all these complexes are diamagnetic. This difference between the two kinds of complexes is discussed in connection with the bonding in, and the structure of, the complexes on the basis of the spectral and magnetic properties. The results for the palladium(II) complexes are compared with those for the corresponding nickel(II) complexes.
The Syntheses and the Structure of Triethanolamine Complexes with Cobalt (II) and Nickel (II)
Authors: Kuge Yoshio , Yamada Shoichiro
Published: July 2006

Triethanolamine complexes with cobalt(II) and nickel(II) have been synthesized as crystals and examined on the basis of analytical data, electronic absorption spectra, and magnetic moments. A complex, Ni{N(CH2CH2OH)3}(ClO4)2, which is formed with Ni(ClO4)2, is concluded to have a six-coordinated configuration, similar to that previously reported for the corresponding chloride, bromide, and nitrate complexes. In cobalt(II) complexes, Co{N(CH2CH2OH)2(CH2CH2O)}X, which are formed with CoX2 (X=Cl−, Br−, or NCS−), the cobalt(II) ion is concluded to take a five-coordinated configuration.
The Cobalt Carbonyl-catalyzed Hydroesterification of 3-(β-Cyano-ethoxy)propene with Carbon Monoxide and Methanol
Authors: Matsuda Akio
Published: July 2006

The cobalt carbonyl-catalyzed hydroesterification of 3-(β-cyanoethoxy)propene with carbon monoxide and methanol occurred in the presence of a small amount of hydrogen at a moderate temperature, methyl 4-(β-cyanoethoxy)butyrate being produced in a much larger amount than methyl 2-methyl-3-(β-cyanoethoxy)propionate. The double-bond isomerization leading to the formation of propionaldehyde dimethylacetal and ethylene cyanohydrin occurred simultaneously. The selectivity to the double-bond isomerization was very large at a low pressure; it decreased as the pressure was increased, with a corresponding increase in selectivity to the hydroesterification. The reaction rate was not increased by the addition of pyridine, but it was increased about tenfold by the addition of palladium chloride. Thus, the reaction could be carried out at a lower temperature in the presence of palladium chloride. The selectivity to the hydroesterification, however, did not increase upon the addition of palladium chloride, as the double-bond isomerization was also accelerated by its addition.
Structure Proof of Diarylmethanes Formed in the Jacobsen Reaction of Monochlorotetramethylbenzenes
Authors: Suzuki Hitomi
Published: July 2006

The Jacobsen reaction of monochlorotetramethylbenzenes was found to yield dichloroheptamethyldiphenylmethanes as by-product. Their indefinite structure proof was made on spectroscopy and synthesis. 1H NMR spectra for a variety of polymethyldiphenylmethanes and their chlorine derivatives were determined.
Aminocyclitols. XX. Bromination of Dl-epi-Inositol
Authors: Suami Tetsuo , Suzuki Akira , Uchida Masaru , Yanagida Shin-ichi
Published: July 2006

Bromination of Dl-epi-inositol yielded two hitherto unknown dibromo-dideoxyinositols, along with two known bromo-deoxyinositols (Dl-5-bromo-5-deoxy-allo-inositol and Dl-1-bromo-l-deoxy-neo-inositol). The proton magnetic resonance spectroscopic studies of the dibromo-dideoxyinositols with the aid of spin decoupling technique established their configurations to be Dl-2,4-dibromo-2,4-didoxy-chiro-inositol and Dl-1,4-dibromo-1,4-dideoxy-chiro-inositol.
Preparation and Properties of the Mixed Dinitro Complexes of Cobalt(III) with the Carbonato or Oxalato Ligand
Authors: Ichikawa Hiroyasu , Shibata Muraji
Published: July 2006

Three new tervalent dinitro complexes of cobalt(III) have been prepared by the use of a tricarbonatocobaltate(III) solution or a similar solution as the starting material. These complexes, [Co(NO2)2(CO3)3]3−, [Co(NO2)2(OX)2]3− and [Co(NO2)2CO3OX]3− are characterized by their absorption spectra in solution. The geometrical structures of these complexes have been determined as of the cis-form on the basis of their IR spectra. The compounds were not stable against decomposition in aqueous solutions: the bis(oxalato) compound was most unstable against the decomposition to the Co(II) state. The stability has been discussed in connection with the specific absorption band of the coordinated NO2− ligand.
Reaction of p-Nitrophenyl Benzenesulfonates with Thiophenoxides
Authors: Tagaki Waichiro , Kurusu Takehiko , Oae Shigeru
Published: July 2006

The reaction of p-nitrophenyl benzenesulfonates has been investigated in dioxane-water solvent. The overall rate constant, kA, was separated into two composite rate constants, kAr, and kSO2, corresponding to the cleavage of C–O and S–O bonds respectively. The reactivities of hydroxide and thiophenoxide in this reaction were compared. The overall rate constant was found to be several times larger with OH− than with PhS−. The reactivity of OH− was largely due to its higher reactivity toward sulfur, while its reactivity toward carbon atom was comparable to that of PhS−. Substituent effect of the nucleophile, thiophenoxide and of the substrate shed some light on the mechanism of this reaction.
Reactive Species in the Explosion of Silver Acetylide. I. Reaction with Saturated Hydrocarbon
Authors: Taki Ko
Published: July 2006

The reactive species produced by the explosion of silver acetylide were found to react with hydrocarbon and to give acetylene and ethylene as the main products. The reactive species must be carbon oligomers. Since, in the reactions with higher hydrocarbons, acetylene and ethylene are also produced, their formation process may be the decomposition of the adduct of the reactive species. From the product distributions, the phase dependence of the ratio of ethylene to acetylene, and the effect of such moderator as carbon dioxide and inert gas, the reactive species are considered to be not only the monoatomic carbon (C1) but also the diatomic carbon (C2). The effect of a NO radical scavenger in the reactions of both ethane and propane is also described.
A Structural Study of the Catalytic Activity in Formaldehyde Polymerization in Liquid Carbon Dioxide
Authors: Kagiya Tsutomu , Narita K\={o}z\={o}
Published: July 2006

The catalytic activities of various acids, bases, and salts in formaldehyde polymerization in a liquid carbon dioxide solution were studied in connection with the structures of the catalysts. The activity of the catalysts increased with decreases in the pKa of Brönsted acids and in the ion-dissociation energy of alkyl acetates, and with increases in the pKa′ of organic compounds containing a nitrogen or oxygen atom, such as triethylamine or diethyl ether, and in the pKa of the conjugated acids of sodium salts. The activity of the salts obtained from a strong acid with various bases increased with a decrease in the pKa′ of the bases, while that of the salts from weak acids with weak bases decreased with an increase in the summation of the pKa values of acids and the pKa′ values of bases, reaching a minimum point and then increasing. The activity of various salts decreased with an increase in the pH in an aqueous solution, reached a minimum point at pH 6, then increased.
Photoinduced Reactions. XXXIV. Photosensitized Oxygenation of 2,4,5-Triphenylthiazole
Authors: Matsuura Teruo , Saito Isao
Published: July 2006

In connection with the photodynamic action of the biological systems, photosensitized oxygenation of a thiazole was investigated. Photooxidation of 2,4,5-triphenylthiazole in methanol in the presence of rose bengal resulted in the formation of benzil and benzamide. On the other hand, photooxidation of 2,4,5-triphenylthiazole in chloroform containing methylene blue as a sensitizer gave N,N-dibenzoylthiobenzamide in good yield. Possible mechanisms for these reactions, involving an endo-peroxide or a zwitterionic peroxide, are discussed.
Reactions of Diarylphosphines, Their Oxides and Sulfides with Isothiocyanates and Thiocyanic Acid
Authors: Ojima Iwao , Akiba Kin-ya , Inamoto Naoki
Published: July 2006

N-Substituted thiocarbamoyldiarylphosphine oxides and sulfides were prepared by the addition reaction of diarylphosphine oxides and diphenylphosphine sulfide with isothiocyanates. Diarylphosphine oxides and diphenylphosphine reacted with ammonium thiocyanate under hydrogen chloride stream to produce diarylphosphinyl- and diarylthiophosphinyl-substituted bis(iminomethyl) sulfides, which are a new type of sulfide. Diphenylphosphine also reacted with thiocyanic acid in ether to give thiocarbamoyldiphenylphosphine and bis(diphenylphosphinyliminomethyl) sulfide. Mechanisms for formation of these bis(iminomethyl) sulfides have been discussed.
The Structure Theory of Water. I. Two State Theory
Authors: Arakawa Kiyoshi , Sasaki Katsutaka
Published: July 2006

A statistical thermodynamic theory was successfully applied to liquid water, based on the two state model which consists of an ice-like structure (class I) and unbonded monomers (class II). The resulting partition function was formulated and calculated using the two quantities, the energy difference between class I and class II, ε, and the free volume per molecule, vf, as the adjustable parameters which were varied within the physically-reasonable range. The magnitudes of ε and vf were estimated to be 3 kcal/mol and 4.0×10−25 cm3 respectively to give the best fit of calculated values to the experimental data. From the partition function obtained, the Helmholtz energy, the internal energy, the entropy, and the specific heat were calculated. The agreement between the calculated values and the experimental data was found to be satisfactory. From the obtained result it may be concluded that the simple two state model is adequate to explain the thermodynamical data for liquid water.
Measurement of Negative Ions Formed by Electron Impact. V. Negative Ion Mass Spectra and Ionization Efficiency Curves of Negative Ions of m⁄e 16, 25 and 41 from Tetrahydrofuran
Authors: Tsuda Satoru , Yokohata Akira , Kawai Michihiro
Published: July 2006

The negative ion mass spectra of tetrahydrofuran, with an emphasis on their relative abundances to the positive ions under 80 eV and 40 eV electron energies, and the ionization efficiency (IE) curves of m⁄e 16(O−),m⁄e 25(C2H−) and m⁄e 41(C2HO−) ions to the extent of 40 eV electron energies were measured. The electron impacts of 80 eV and 40 eV gave almost the same distribution of m⁄e for negative ion mass spectra. The relatively strong peaks were observed at m⁄e 24(C2−) ions for 80 eV and m⁄e 14(CH2−) ions for 40 eV, besides the commonly strong peaks of m⁄e 25(C2H−), m⁄e 16(O−) and m⁄e 41(C2HO−) ions. The comparison of the yield of C2H− ions with that of C3H6+ gave the values 9.4×103 and 2.7×104 for C3H6+/C2H− at 80 eV and 40 eV electron energies, respectively. The reaction schemes expected to occur at each onset observed in the IE curves were also discussed. It is of interest to note that C2H− ions are not obtained in the range of low energy of electrons, but become observable at ∼23.5 eV.
The Catalytic Activity of Onium Compounds in the Homogeneous Liquid Phase Oxidation of Cumene and α-Pinene
Authors: Fukui Kenichi , Ohkubo Katsutoshi , Yamabe Tokio
Published: July 2006

The catalytic activity of onium compounds was studied in the homogeneous liquid phase oxidation of cumene and α-pinene. The onium salts, particularly sulfonium, phosphonium, selenonium, arsonium and telluronium were found effective. This result is connected to the fact that the central atom in these onium has vacant d orbitals. Among the anions of the onium salts tested, phosphate and sulfate were most effective. The aryl substituents in the central sulfur in sulfonium lessened the activity, while alkyl substituents made it greater. These facts were attributed to charge migration from the substituents and the anionic part to the central atom.
On the Viscosity of Liquid Oligotrifluorochloroethylene
Authors: Yoshida Naosato , Hamada Shuichi , Shirai Toshiaki
Published: July 2006

The viscosities and densities of liquid oligotrifluorochloroethylene were measured over a molecular-weight range from 820 to 1090 at temperatures from 40°C to 100°C. The temperature dependences of the viscosities did not show an Arrhenius-type variation, but were extremely adaptable in the WLF equation; i. e., a viscoelastic behavior was shown under the present experimental conditions. The apparent activation energies, ΔHa, for the viscous flow of the liquid samples were comparatively large and increased with an increase in the number-average molecular weight. The logarithm of the viscosity, logη, varied linearly with the logarithm of the number-average molecular weight, logη=AlogMn+B. The slopes, A, of the linear relationships were estimated to be 11.0, 10.4, 9.3, and 8.4 at 50, 60, 70, and 80°C respectively. The values of the slopes, A, were very much larger than unity in the case of usual organic polymers below the critical values of the molecular weight, and they decreased with an increase in the temperature.
Infrared Study of Rotational Isomers of meso- and racemic-2,3-Dibromobutane
Authors: Iimura Kazuyoshi
Published: July 2006

The infrared spectra of meso- and racemic-2,3-dibromobutanes in solution and in gaseous states were obtained in the study of the rotational isomers. The occurrence of three rotational isomers was confirmed for both meso- and racemic-isomers. The quantitative estimation of the equilibrium concentrations of the rotational isomers was also made in various solvents. The energy difference between the rotational isomers was determined by measuring the temperature-dependence of the absorption intensities of v(C–Br) vibrations.
Polarographic Study of Metal Complexes. VIII. Dicyanobis-(ethylenediamine) cobalt(III) Complex with a cis-Configuration
Authors: Maki Nobufumi , Yamamoto Kouei , Sunahara Hiroshi , Sakuraba Shukichi
Published: July 2006

In an aqueous solution containing an excess of ethylenediamine, i. e., under the conditions where the aquation is prevented, the dicyano-cobalt(III) complex, cis-[Co(CN)2en2]NO3, has been found to be reduced in three steps at the dropping mercury electrode (DME). The first step, corresponding to the acceptance of one electron, represents the reduction from the cobalt(III) to the cobalt(II) state, while the second and the third step were interpreted as being due to the reduction of two kinds of the cobalt(II) species formed by the overall rearrangement of ligands in solution. One such kind of cobalt species is the binuclear tetracyanocobaltate(II) complex, [Co(CN)4-en-Co(CN)4]4−, which is reduced to the metal through the cobaltate(I) complex, while the other is the cobalt(II) complexes with ethylenediamines in an equilibrium state, which are reduced directly to the metal at the DME. Namely, the second step represents the reduction from the cobalt(II) complex of the former to the cobalt(I) state, while the third step, denoting the reduction to the metal, was observed only on the dE⁄dt-E curve of the oscillopolarogram, but not on the current-potential curve due to the maximum wave. In the non-aqueous solution of dimethyl sulfoxide, the dicyano-cobalt(III) complex, cis-[Co(CN)2en2]ClO4, undergoes the step-by-step reduction of Co(III)→Co(II)→Co(I)→Co(0), as it were, at the DME. Neither aquation nor rearrangements of ligands take place throughout reductions under these experimental conditions, that is, even in lower oxidation states of the cobalt.
On the Oxidation of Guaiazulene
Authors: Kohara Kazuko
Published: July 2006

Guaiazulene was oxidized with potassium permanganate and with selenium dioxide according to the Treibs procedure. An acidic and a neutral crystalline compounds obtained from the permanganate oxidation in acetone were identified by means of UV, IR, and NMR spectrum measurements as 4-methyl-7-isopropylazulene-1-carboxylic acid and 1-formyl-4-methyl-7-isopropylazulene respectively. It was also confirmed that the selenium dioxide oxidation of guaiazulene in acetone gave 3-formylguaiazulene and 3,3′-diguaiazulenylacetone, the chemical structure of which had already been established by Treibs.
Homolytic Chlorination of Aliphatic Compounds. II. Photochlorination of Aliphatic Nitriles
Authors: Kosugi Masanori , Takeuchi Kohji , Migita Toshihiko
Published: July 2006

Acetonitrile, propionitrile, n-butyronitrile and pivalonitrile were photochlorinated competitively at 40°C in the presence of an appropriate chlorinated ethane, and relative amounts of the chlorinated products were determined by v.p.c. From the results the relative reactivities of C-H bonds toward hydrogen abstraction by chlorine atom were estimated. A linear free energy relationship was observed between σ* value of X and the reactivity of CH3–X toward chlorination (X: –CN, –CH2CN, –CH2CH2CN, –CMe2CN). This indicates that cyano group will affect the reactivities of these C-H bond through its inductive effect.
Energy Transfer from the Triplet Excited States of Aromatic Molecules to Chromium(III) Complexes
Authors: Ohno Takeshi , Kato Shunji
Published: July 2006

The quenching efficiencies of five tervalent chromium complexes on the phosphorescence of erythrosin and benzil have been compared at the temperatures of dry ice and liquid nitrogen. The results were well explained in terms of the collisional energy transfer. It was observed that aromatic ligands enhanced the rate of the energy transfer even if the triplet energy of the donor was lower than that of the ligands.
Effect of γ-Preirradiation on Catalytic Activity of Nickel Oxide for the Oxidation of Carbon Monoxide
Authors: Tezuka Yoshisato , Takeuchi Toyosaburo
Published: July 2006

The change in NiO catalytic activity upon the variation in the irradiation of γ-rays in the presence of O2 gas was studied. Activities were determined for the reaction of CO with NiO and for the oxidation reaction of CO on NiO. The results showed a decrease in the CO-NiO reaction rate with an increase in the irradiation of NiO, particularly in the absence of oxygen; if the irradiation was more than 7×107R, the reaction rate increased as both the irradiation in the presence of oxygen and the oxygen partial pressure increased. The activity change in NiO was explained by assuming the migration of the specially-active oxygen into the oxide bulk by means of the irradiation of γ-rays.
Oxidation Reactions of 2,4,6-Tri-t-butylaniline
Authors: Okazaki Renji , Hosogai Takeo , Hashimoto Masayoshi , Inamoto Naoki
Published: July 2006

Oxidation reactions of 2,4,6-tri-t-butylaniline with lead tetraacetate (LTA), lead tetrabenzoate (LTB), peroxybenzoic acid (PBA) and benzoyl peroxide (BPO) were studied and mechanisms of these reactions were briefly discussed. In the reaction with LTA, 4-acetoxy-1-imino-2,4,6-tri-t-butyl-2,5-cyclohexadiene (I), 2-acetamido-3,5-di-t-butylphenol (II) and 2-acetylimino-3,5-di-t-butyl-3,5-cyclohexadienone(III) were produced. Oxidation with LTB gave 4-benzoyloxy-1-imino-2,4,6-tri-t-butyl-2,5-cyclohexadiene (VI, major product) and 2-benzamido-3,5-di-t-butylphenol (VII). The reaction products with PBA were 2,4,6-tri-t-butylnitrosobenzene (VIII) and VII. In addition to the last two compounds, VI and 2,2′,4,4′,6,6′-hexa-t-butylazobenzene (XI) were obtained in the case of BPO.
Triazene Rearrangement. III. A Kinetic Study of the Rearrangement of N-Methyldiaryltriazenes
Authors: Yamada Takashi
Published: July 2006

The rate constants of the hydrochloric acid-catalyzed rearrangement of N-methyldiaryltriazenes were determined in 95% aqueous ethanol in the presence of N-methylaniline. Electrondonating substituents on the diazo-part in triazene promoted the rearrangement. A Hammett plot of the rate constants gave a good straight line. The negative ρ-value (−3.63 at 30.0°C) and the large positive values of the entropy of activation suggested that the rate-determining step in this rearrangement is the dissociation of protonated triazene; this is in contrast with the case of the Friswell-Green mechanism. This theory was suppoted by such a solvent effect as that the rate decreased a little as the polarity of the solvent increased. The kinetic behavior of triazenes in the absence of N-methylaniline, and the incorporation of N-methyl-o-toluidine into the product in the rearrangement of 1-p-chlorophenyl-3-methyl-3-phenyltriazene (Id), were also discussed in connection with the above mechanism.
Structure of Vinylacetylene Determined by Electron Diffraction and Spectroscopy
Authors: Fukuyama Tsutomu , Kuchitsu Kozo , Morino Yonezo
Published: July 2006

The average structure of vinylacetylene has been determined by making combined use of the electron-diffraction intensities obtained in the present study and the rotational constants supplied by microwave spectroscopy. The two sorts of data have been found consistent to the uncertainties given below. With the molecular symmetry assumed to be Cs, the following parameters have been obtained in regard to the zero-point average structure: r(C–C)=1.4310±0.0034, r(C=C)=1.3416±0.0042, r(C≡C)=1.2086±0.0028, r(C–H)vinyl=1.087±0.010, r(C–H)ethynyl=1.062±0.018Å, ∠(C=C–C)=123.1±0.5°, ∠(C–C≡C)=177.9±1.2°, ∠(H–C=C)=120.6±1.5°, ∠(C≡C–H)=182.3±3.8°. There seems to be a significant difference between the C–C length of vinylacetylene and that of propynal. The result has been discussed in terms of the bond-order bondlength correlation.
π-Allylie Coordination of Ethyl Acetoacetate to Palladium(II)
Authors: Tezuka Yoshisato , Ogura Tetsuya , Kawaguchi Shinichi
Published: July 2006

The ethanolysis of diketene is accelerated by the addition of sodium tetrachloropalladate(II). Yellow crystals separated in the end of this reaction were identified as di-μ-chlorobis(π-1-ethoxycarbonyl-2-hydroxyallyl)dipalladium(II) on the ground of analytical data, molecular weight and infrared spectrum. The same complex was also prepared directly by the reaction of palladium(II) chloride with ethyl acetoacetate in water.
The Stability of Fused Rings in Metal Chelates. IV. Preparation and Relative Stability of Copper(II) Complexes with Tetradentate Schiff Base Ligands
Authors: Nakao Yasuo , Nonagase Naoki , Nakahara Akitsugu
Published: July 2006

Relative stability of sixteen aldehyde- and the corresponding ketone-Schiff base chelates has been investigated in terms of their decomposing temperature and half-wave potential against the reduction of copper(II) at the dropping mercury electrode. The previous conclusion, established for copper(II) tridentate Schiff base complexes, that Schiff base chelates of aldehydes are generally less stable than those of corresponding ketones has been proved to be valid also for copper(II) tetradentate Schiff base complexes if there is no serious steric hindrance in the Schiff base ligand. As a result of this investigation, six new copper(II) chelates were synthesized and characterized.
Synthesis of 1- and 2-Morpholinophenazine Derivatives
Authors: Endo Hideo , Tada Masao , Katagiri Ken
Published: July 2006

A number of new morpholinophenazines have been prepared by the reactions of various halogenophenazine derivatives with morpholine. It has been found that the replacement of the halogen atom of halogenophenazine-N-oxides with morpholine is accompanied by the removal of the oxide group and that no morpholinophenazine-N-oxides are formed in these reactions.
Studies of Aminosugars. XXI. The Total Synthesis of Kanamycin C
Authors: Umezawa Sumio , Koto Shinkiti , Tatsuta Kuniaki , Tsumura Takayuki
Published: July 2006

4-O-(3-O-Benzyl-2-carbobenzoxyamino-4,6-O-isopropylidene-2-deoxy-α-d-glucopyranosyl)-N,N′-dicarbobenzoxy-2-deoxystreptamine has been prepared from paromamine and condensed with 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-d-glucopyranosyl chloride by a modified Koenigs-Knorr reaction. The identity of the synthetic α,α-diglycoside with a substance of the same structure derived from natural kanamycin C was shown. Removal of the masking groups gave the product identical with natural kanamycin C.
Photochemistry of Acetanilide. III. The Secondary Processes in the Photochemical Reaction
Authors: Shizuka Haruo
Published: July 2006

The photochemical secondary processes of acetanilide have been studied. The photochemical reaction of p-methylacetanilide at 2537 Å did not produce the p-rearrangement product, but the o-rearrangement one. The quantum yields of the o-rearrangement and of the disappearance of p-methylacetanilide were 0.092 and 0.12 respectively. Comparing the quantum yields of acetanilide with those of p-methylacetanilide, the values of the quantum yields for the predissociation of the N–C bond, the back reaction, and the recombination ratio were estimated to be 0.25, 0.10, and 0.9 respectively. These results indicate that the recombination reaction between the pair radicals formed by the predissociation of the N–C bond occur efficiently in a solvent cage. The rate constants of the back reaction, the o-rearrangement, and the p-rearrangement were proportional to the odd π electron densities of the anilino radical. No intermediate was observed by the flash photolysis. The small dependence of the quantum yields of acetanilide on the temperature supports the predissociation mechanism previously described. On the basis of these studies, the mechanism of the photochemical reaction of acetanilide in the liquid phase has been proposed.
Infrared Spectra of Acylureas and NN′-Deuterated Acylureas
Authors: Uno Toyozo , Machida Katsunosuke , Hanai Kazuhiko , Saito Yutaka
Published: July 2006

The infrared spectra of seven monoacylureas and their NN′-deuterated compounds have been measured in the region between 3600 and 450 cm−1. A number of characteristic absorption bands of the –CONHCONH2 and –CONDCOND2 groups have been found and assigned by referring to the infrared spectra of related compounds and the isotopic frequency shifts. Partial deuteration by mixtures of water and heavy water has been made to distinguish the absorptions due to the NH and NH2 groups from each other. The features of infrared spectra of monoacylureas can be explained by regarding them as composite spectra of aliphatic imides and urea. From the effect of the alkyl frame-work vibrations for the imide III frequency, it is suggested that the RCONH– group of monoacylureas takes the trans conformation.
Polymerization of N-Vinylcarbazole in the Presence of β-Cyanoacrolein
Authors: Sumitomo Hiroshi , Takemura Ichiro
Published: July 2006

It was found that N-vinylcarbazole (VCZ) initiated the polymerization in the presence of β-cyanoacrolein (CAL) even in air at room temperature. The polymerization of VCZ induced by CAL was investigated in benzene at 60°C. Polymer formed was found to be VCZ homopolymer. The rate of polymerization attains to a maximum at the mole fraction of CAL of about 0.65 in the monomer mixture. The products obtained from the terpolymerization in the system of CAL-VCZ-Styrene in benzene at 60°C contain no CAL unit and exclusively consist of the VCZ component. The composition curve of the copolymer is contrasted with that of a radical initiated copolymer. In view of these results, as well as the Q-e values of both CAL and VCZ, it seems possible that the cationic polymerization of VCZ is induced by some donor-acceptor type interaction between VCZ and CAL.
Solvated Electron Formed in Water by the Silent Electric Discharge in Argon Atmosphere
Authors: Yokohata Akira
Published: July 2006

Based on radiation chemistry of water a study on the chemical changes resulting from the silent electric discharge of aqueous solution under argon atmosphere was made for the purpose of elucidating the nature of the reducing species formed. In the neutral aqueous ClCH2COOH system the effects of such additives as CH3OH and NO3− on the yield of Cl− and in the system containing NO3− the yield of NO2− were investigated. Moreover, in the alkaline aqueous K3Fe-(CN)6 system emphasis was placed on the yield of aquocomplex. In view of the non-dependence of the yield of Cl− on the concentration of additive NO3− and of the low yields of NO2− and Fe(CN)5OH23− produced, it was concluded that in the silent electric discharge the yield of solvated electrons which react with solutes in the bulk of water is very small (G\lesssim0.06). Reasons for the low yield of solvated electrons are briefly described.
Spectroscopy and Magnetic Properties of Nitrosylpentaamminechromium Salts
Authors: Kobayashi Hanako , Tsujikawa Ikuji , Mori Masayasu , Yamamoto Yoshihisa
Published: July 2006

Nitrosylpentaamminechromium chloride (brown), perchlorate (green) and other salts of different colors were studied by visible, IR and ESR spectroscopy and by magnetic susceptibility measurements. The easy shift of visible absorption bands caused by the replacement of outer anions which are responsible for the color difference, ripples observed in one of the absorption bands, g-values from ESR and a spin state 1/2 suggested by the susceptibility measurements are interpreted on the basis of a qualitative MO theory for metal nitrosyl complexes.
Geochemical Fractionation of Induced Radionuclides in Fresh Nuclear Debris through the Atmosphere—Np-239 and Co-60
Authors: Sotobayashi Takeshi , Suzuki Toshio , Koyama Seitaro
Published: July 2006

The atmospheric fractionation of induced radionuclides is discussed in some detail on the basis of results obtained by making a radiochemical analysis of fresh nuclear debris originating from recent Chinese nuclear test explosions. Among fresh nuclear debris particles collected at Niigata about 4000km downwind from the Chinese test site, the trend for the enrichment of 239Np was somewhat modified as compared with that derived from an averaged sample collected by a large-scale and high-altitude sampling procedure; more 239Np was present in smaller-size fallout particles. Furthermore, it was found, in rain-water samples collected after the third Chinese nuclear explosion, that the atomic ratio at time-zero of 60Co/95Zr increased with a decrease in the 95Zr-concentration in rain and vice versa. This suggests that the atmospheric fractionation of 60Co-rich particles from 95Zr-rich ones takes place during the travel of atomic clouds around the world.
Asymmetric Reactions. II. Anomalous Stereoselectivity of the Grignard Reaction with N-Benzyl-2,3-O-isopropylidene-d-glyceraldimine
Authors: Ohgo Yoshiaki , Yoshimura Juji , Sato Tetsuo
Published: July 2006

Stereoselectivity of the organomagnesium reaction with N-benzyl-2,3-O-isopropylidene-d-glyceraldimine was examined under various conditions (change of molarity, solvent, and composition ratio of reagents). The selectivity was not effected by the molarity of the reagents but by the solvent. When the substrate was treated with a mixture of various ratio of magnesium bromide and diphenylmagnesium, a remarkable effect of the ratio on the stereoselectivity was observed. Maximum ratio of erythro/threo was obtained at the point of equimolar mixture of magnesium bromide and diphenylmagnesium in ether. The structure of the transition intermediate was discussed.
Organic Syntheses by Means of Metal Complexes. III. Cobalt Carbonyl-catalyzed Carbonylation of β-Propiolactone
Authors: Mori Yoichi , Tsuji Jiro
Published: July 2006

It was found that the carbonylation of β-propiolactone can be carried out in the presence of dicobalt octacarbonyl. Butyrolactone and succinic acid were obtained by the reaction of β-propiolactone with carbon monoxide and hydrogen. Succinic anhydride was obtained by the reaction with carbon monoxide.
Nitroalkenylferrocene. II. The Condensation Reaction of Nitroolefins with Aromatic Carbonyl Compounds
Authors: Shiga Mikio , Kono Hiromichi , Motoyama Izumi , Hata Kazuo
Published: July 2006

The condensation reactions of β-ferrocenylnitroethylene (1), with various aromatic aldehydes in the presence of an excess of sodium methoxide were investigated. The main products of these reactions were ferrocenylnitroalkenols (2), which were obtained from precursory sodium salts by the acidification of the reaction mixture. Sodium nitroalkanolate (4) was postulated as an intermediate in these reactions. On the other hand, the reaction of 1 with acetophenone resulted in a different condensation, one giving 1-benzoyl-2-ferrocenyl-3-nitropropane (11) and 1-benzoyl-2-ferrocenylethylene (12).