bluuebunny/crossref_metadata_2025 huggingface dataset:
Darstellung von Aromatischen Keteniminen aus Diphenylmethylenarylaminen
Authors: Ichimura Kunihiro , Ohta Masaki
Published: July 2006

A new route to aromatic ketenimines is described. The reaction of diphenylmethylenearylamines with chloroform/t-butoxide gave 1,3,3-triaryl-2,2-dichloroaziridines which could be pyrolytically converted to N-aryl-α-chlorodiphenylacetimidoyl chloride. When the 2,2-dichloroaziridines were treated with excess sodium iodide in acetone, aromatic ketenimines were obtained in excellent yields.
The Stereoselection Rule for Electrocyclic Interactions
Authors: Fukui Kenichi , Fujimoto Hiroshi
Published: July 2006

A general stereoselection rule governing the electrocyclic interactions has been proposed with a molecular orbital rationale. The reactions discussed from a unified point of view cover the ring-closure of polyenes, the Diels-Alder additions, 1,4-dipolar additions, the Cope and the Claisen rearrangements, the hydrogen and the proton migrations, 1,3-dipolar additions, the ring-opening of cyclic olefins, the deamination of cyclic unsaturated imines, 1,2-noncycloadditions, 1,2-eliminations, the nucleophilic displacement with allylic rearrangements, and other cyclic intermediate or complex formations. The relation to the molecular orbital symmetry has been also discussed.
A Spectrophotometric Study of the Thorium Complexes of o-, m-, and p-Nitrophenyl-azo-chromotropic Acids
Authors: Tôei Kyoji , Miyata Haruo , Kimura Hirosumi
Published: July 2006

o-, m-, and p-Nitrophenyl-azo-chromotropic acids were prepared as colorimetric reagents for thorium. The acid dissociation constants of the reagents have been determined spectrophotometrically, their pK1 values being 8.96, 8.60, and 8.77 for the and o-, m-, and p-compounds respectively at 25°C and when μ=0.1. The reagents form violet 1 : 1 complexes in an acidic solution. The apparent stability constants have been measured spectrophotometrically. The order of the apparent stability constants of the complexes agrees with that of the first acid dissociation constants of the reagents; m-nitro>p-nitro>o-nitro compounds.
Oxidation of Propylene over the Tin-Antimony Oxide Catalysts. I. Dependency of Acrolein Formation on the Composition of Catalyst and Calcination Conditions
Authors: Wakabayashi Katsuhiko , Kamiya Yoshio , Ohta Nobuto
Published: July 2006

For the purpose of elucidating the catalysis of the binary system consisting of Sn and Sb oxides, recommended in the patent for the oxidation of propylene to acrolein, the oxidation of propylene has been studied; in addition, the X-ray patterns of the system have been investigated. The mixtures of this binary system after sintering were different in color according to the catalyst composition and the calcination conditions. It was found that the color of the catalyst is closely connected with the formation of acrolein, and also that the blue-colored catalysts are effective in the selective production of acrolein. The pure tin oxide catalyst yielded mainly carbon dioxide and monoxide, while the pure antimony yielded scarcely any product. However, a selectivity to acrolein of more than 70% was obtained at 450°C over a catalyst with an optimal composition, for example, one with a Sn to Sb atomic ratio of 3 : 1 which had been calcined at 1000°C for 3 hr. The formation of acrolein was investigated as a function of the catalyst composition and the calcination conditions. According to the X-ray data, Sb oxide was soluble in Sn oxide, thus forming solid solutions, and the mixtures’ becoming colored was attributable to the formation of the solid solutions. It was concluded that the formation of acrolein over this binary system is closely connected with the solid solutions formed between Sn and Sb oxides.
Effects of Pressure on the Chemical Properties of the Solid Surface. IV. Dehydrogenation of Isopropanol on the Compressed CuO-Cr2O3 System
Authors: Ogino Yoshisada , Ono Takehiko
Published: July 2006

In order to examine the idea that the chemical properties of a solid surface would vary on compressions, the catalytic activities of CuO-Cr2O3 samples compressed at 340–5120 kg/cm2 were measured at 100–200°C and under 1 atm pressure. In addition, some experimental studies of the structure of the samples were carried out. The activity of the sample compressed before the reduction decreased monotonously with the compression. It was considered that the retardation of the reaction due to an intra-particle diffusion might be the cause of this activity change. On the other hand, in the case of the sample compressed after the reduction, an unexpected rise in the catalytic activity was found to result from the compression of 3000–4000 kg/cm2. The cause of this phenomenon was thought to be an increase in the surface area resulting from a disintegration of the sample particles. Further, the activation energy was found to decrease on compression. From the results of electron-diffraction studies, it seems that the decrease in the lattice distances of surface copper may be thought to be the cause of this activation-energy change.
Organic Reagents used in Inorganic Analysis. I. Acid Dissociation Constants of Hydroxamic Acids and N-Arylhydroxamic Acids
Authors: Dutt N K , Seshadri T
Published: July 2006

A number of derivatives of hydroxamic acids and N-arylhydroxamic acids have been prepared and their acid dissociation constants have been determined in aqueous solutions. The variation of pK has been discussed.
Theoretical Calculation of Fluorescent X-Ray Intensities of Nickel-Iron-Chromium Ternary Alloys
Authors: Shiraiwa Toshio , Fujino Nobukatsu
Published: July 2006

The fluorescent X-ray intensities of nickel-iron-chromium alloys which cover the entire range of the system are obtained by theoretical calculation. The calculated results show that the iron fluorescent X-ray intensity is much affected by the amount of the other elements, while the nickel and chromium fluorescent X-ray intensities are less affected. The calculated results agree with the experimental results; their difference is less than 1%. In the calculations, the intensities of the primary, the secondary, and the tertiary fluorescent X-rays are obtained, where the primary fluorescent X-rays are defined as being excited by incident X-rays only; the secondary fluorescent X-rays as excited by the primary, and the tertiary fluorescent X-rays, as excited by the secondary fluorescent X-rays. The calculated results show that the secondary fluorescent X-rays are significant, but the tertiary fluorescent X-rays form only a small percentage of the total fluorescent X-rays at most.
The Reaction between Mercury(II) and Organic Compounds. III. Separation and Quantitative Determination of Basic Amino Acids with Mercury(II)-Salt Precipitants
Authors: Kai Fumiaki
Published: July 2006

The particular reactivities between mercury(II) chloride and basic amino acids give such products as [Arg-Hg]Cl·HgCl2, [His-Hg]Cl·HgCl2, and [Lys-Hg]Cl·HgCl2. The possibility of the application of these reactivities to the separation and determination of basic amino acids has now been studied. The products were obtained preferentially from a mixture of various amino acids. The isolation of the mixture of the products could be carried out effectively by the utilization of the different solubilities of the products in aqueous sodium hydroxide. All basic amino acids except His usually do not show any absorption in the ultraviolet region. The above products, however, showed characteristic absorption curves which differed from those of the components. In these spectra, although there were no absorption maxima, calibration curves which were in a good linear relationship could be obtained at any proposed wavelength. By measuring the absorbances of aqueous hydrochloric acid (pH 1.2) or sodium hydroxide (pH 12.0) solutions of the products, quite a small amount of each basic amino acid could be determined spectrophotometrically in the ultraviolet region, within the detectable limits of 4×10−4−6×10−5  m. The accuracy obtained by the determination of the basic amino acid content in an ovalbumin makes it possible to recommend the present methods.
The Rearrangement of 1-Butene-1-14C over the Chromia-Alumina Catalyst
Authors: Okamoto Yoshiyuki , Happel John , K\={o}yama Hiroaki
Published: July 2006

An investigation of the radioactive carbon rearrangement in the dehydrogenation reaction to produce radioactive 1,3-butadiene from 1-butene-1-14C over the chromia-alumina catalyst was carried out under various conditions. The extent of the carbon-14 rearrangement from the 1-position in the 1-butene to the 2-position in the 1,3-butadiene produced in the reaction was large at higher temperatures. The existence of four-membered ring intermediates on the catalyst was suggested as a possible mechanism for the rearrangement.
The Effect of Sulfur Dioxide in the Radical Reactions of Anthracene
Authors: Takeuchi Hiroshi , Nagai Toshikazu , Tokura Niichiro
Published: July 2006

The reaction of anthracene with benzoyl peroxide (BPO) in benzene solution gives 9-benzoyloxyanthracene (I), without forming any 9,10-dibenzoyloxyanthracene (II). However, in the presence of sulfur dioxide (SO2), the above mentioned reaction produces II, 9,9′-dianthrone (III), and anthraquinone (IV), without any I. These reaction mechanisms could be interpreted as follows: It is considered that, in the addition reaction of anthracene with a benzoyloxy radical (PhCOO·), the 9,10-dihydro-9-benzoyloxyanthryl radical (V) is formed. In the absence of SO2, an intra-molecular aromatization of V occurs by a hydrogen abstraction and a delocalization of the radical. On the contrary, in the presence of SO2, the localization of the V radical is enhanced by the interaction with SO2, thus promoting the reactivity toward the benzoyloxy radical. Moreover, in the experiments using α, α′-azobis-isobutyronitrile (AIBN) in place of BPO, the addition products of 2-cyano-2-propyl radicals with anthracene were isolated. This phenomenon could be explained by the fact that the hydrogen abstractions of the addition products do not occur.
The Oxidations of Thiols and Their Lead Salts
Authors: Mukaiyama Teruaki , Endo Tadashi
Published: July 2006

Thiols (thiophenol, thiobenzoic acid and diethyldithiocarbamic acid) react with lead dioxide, chromium trioxide or lead tetraacetate to yield the corresponding metal salts and disulfides together with water or acetic acid. The oxidations of thiophenol by multivalent iodine compounds have been studied. In addition, the redox reaction between a lead salt of a thiol and a disulfide has been investigated and the following order of oxidizing power of the disulfides is indicated: tetra-ethylthiuram disulfide > bis(thiobenzoyl)disulfide > dibenzoyl disulfide > diphenyl disulfide.
Azetidines. II. Some Functional Derivatives of Azetidines
Authors: Chen Teng-yueh , Sanjiki Tetutaro , Kato Hiroshi , Ohta Masaki
Published: July 2006

The sodium methoxide-catalyzed cyclization of methyl α-tosylamino-γ-chlorobutyrate gave methyl 1-tosylazetidine-2-carboxylate, which was then converted to the corresponding carboxylic acid and carbinol. 1-Acetyl-2,2,4,4-tetramethylazetidine-3-carboxylic acid was prepared by the photolysis of 1-acetyl-4-diazo-2,2,5,5-tetramethylpyrrolidin-3-one. The formation of 1-acetyl-2,2,4,4-tetramethyl-3-azetidinone was confirmed.
Aminocyclitols. XIV. The Synthesis of Streptamine and Actinamine
Authors: Ogawa Seiichiro , Abe Tadashi , Sano Hiroshi , Kotera Keiji , Suami Tetsuo
Published: July 2006

Streptamine, actinamine and scyllo-inosatriamine-1,3,5 have been synthesized from 1,2,3,5-tetra-O-acetyl-4,6-diazido-4,6-dideoxy-myo-inositol. Hydrolysis of this compound gave 5-O-acetyl-4,6-diazido-4,6-dideoxy-myo-inositol, which was a key compound for the synthesis of streptamine and scyllo-inosatriamine-1,3,5, and 4,6-diazido-4,6-dideoxy-myo-inositol which was derived to actinamine. PMR spectra were mainly used to establish the configurations of the new compound obtained.
SCF MO Calculations of Uracil, Lumazine, and Alloxazine, and Their Tautomeric Isomers
Authors: Nishimoto Kichisuke
Published: July 2006

The electronic structures of uracil, lumazine, and alloxazine, and all their possible tautomeric isomers have been calculated by the LCAO MO SCF method based on variable beta approximation. The calculated singlet transition energies for diketo forms agree quite well with the experimental results. The present theory suggests that some tautomeric forms of lumazine and alloxazine will behave as both electron donors and electron acceptors. In biological systems, uracil, lumazine, alloxazine, and isoalloxazine will act as both oxidizers and reducers through hydrogen bonds with some molecules, such as protein and DNA.
Complexes of Europium(III) with Nitrate and Chloride Ions in 4 m H(ClO4) and Na(ClO4)
Authors: Sekine Tatsuya , Sakamoto Ichiro , Sato Tatsuo , Taira Tomoe , Hasegawa Yuko
Published: July 2006

The complex formation of europium(III) with nitrate and chloride ions in 4 m H(ClO4) and 4 m Na(ClO4) was studied at 25 °C, using radioactive tracers at very low concentrations and in conjunction with cation exchange resin. The stability constants were determined graphically by a “curve-fitting” method. The stability constants obtained were as follows:

(Remark: Graphics omitted.)

It was concluded that the stability of the nitrate complexes is nearly comparable with that of the chloride complexes.
Electron Spin Resonance Studies of Diphenyl Nitric Oxide Derivatives
Authors: Yamauchi Jun , Nishiguchi Hiroaki , Mukai Kazuo , Deguchi Yasuo , Takaki Hideo
Published: July 2006

A series of diaryl nitric oxide radicals have been studied by the use of the electron spin resonance (ESR) technique. Several methyl derivatives of diphenyl nitric oxide were synthesized and their ESR spectra investigated. It has been shown that the hyperfine coupling constants of 14N, especially those of protons, are much affected in the case of the ortho-methylated compounds as a result of steric hindrance, which is discussed using the Hückel molecular-orbital theory and the valence-bond theory. In conclusion, two benzene rings of diphenyl nitric oxide derivatives are equivalently distorted for the symmetrically-substituted compounds and unequiv-alently for the unsymmetrically-substituted compounds. Furthermore, this tendency is strengthened by ortho-substitution.
Formation Constants of Chromium(III) Complexes with Phthalic Acid and the Jumping Property of the Solid Complex
Authors: Higashi Kunishige , Hori Kuniko , Tsuchiya Ryokichi
Published: July 2006

Applying the continuous variation method to a mixed solution of the hexaaquochromium(III) perchlorate and phthalic acid, the complex formed in the aqueous solution was found to have mole ratios of chromium and ligand material of 1 : 1 and 1 : 3 at pH 1–2 and 3–4 respectively. The formation constants of the chromium(III) complexes with phthalic acid were determined by the pH method. The step-by-step formation constants were found to be log k1=5.52, log k2=4.48, and log k3=2.48 respectively. The solid chromium(III) complex with phthalic acid was also prepared. Though it was found to be an amorphous solid by X-ray diffraction measurement, the composition was close to K3[Cr3(ph)3(OH)6(H2O)6] (ph=C8H4O42−). A curious phenomenon was observed in the moist air; the substance in the dried state jumped, probably due to the absorption of water vapor.
Cobalt(IV) Amminecomplexes with 5-Nitrosalicylato Ligands. I
Authors: Yamamoto Yoshihisa , Ito Kazuo , Yoneda Hayami , Mori Masayasu
Published: July 2006

Co(IV) compounds of the formulae:

(Remark: Graphics omitted.)

have been isolated from the reaction product of salicylatotetraamminecobalt(III) chloride and 60% nitric acid. Valency four was ascertained by magnetic measurements (μeff=1.98 B.M. (A), 1.71 B.M. (B)) and iodometry.
Absorption Spectra and Circular Dichroisms of Metal Complexes. I. Platinum(II)-, Palladium(II)- and Gold(III)-Complexes Containing Optically Active Diamines
Authors: Ito Haruko , Fujita Junnosuke , Saito Kazuo
Published: July 2006

In order to study the nature of absorption bands in square-planar metal complexes of d8 type, a number of platinum (II), palladium (II) and gold(III) complexes containing l-propylenediamine and l-cyclohexanediamine were prepared and their circular dichroism (CD) and rotatory dispersion (RD) as well as absorption spectra (AB) were measured. Three or four absorption bands corresponding to d–d transitions were observed for each platinum(II) and palladium(II) complex. All the complexes, except for [Au(l-pn)2]Cl3, [Au(l-chxn)2]Cl3 and [PdCl2(l-pn)], give two possitive CD bands in the wavelength region from visible to 210 mμ, which are assigned to the spin-forbidden and spin-allowed A1→E transition. Both [Au(l-pn)2]Cl3and [Au(l-chxn)2]Cl3 exhibit only one strong positive CD band corresponding to the ligand field transition probably mixed with charge transfer transition. [PdCl2(l-pn)] gives a weak negative and a strong positive band corresponding to the transitions, A1→A2 and A1→E, respectively. The CD strength of the bis-l-diamine complexes is almost twice those of the mono-l-diamine complexes. The vicinal effect of l-cyclohexanediamine was about twice as strong as that of l-propylenediamine. Absorption spectra of the [MX4]n− (M=Pt2+, Pd2+ and Au3+, X=Cl− and Br−) show a shoulder and two bands in the ultraviolet region adjacent to the ligand field bands. The shoulder band was assigned to the symmetry forbidden, and the two strong bands to the symmetry allowed pπ→dx2−y2 and pσ→dx2−y2 charge transfer transitions. In the [MBr4]n−, the pπ→dx2−y2 band splits into two components, corresponding to A1g→A1u and the other A1g→Eu transition.
Studies of Heteroaromaticity. VIII. Reactivity of Some Nitrile Oxides Conjugated with a Double Bond
Authors: Sasaki Tadashi , Yoshioka Toshiyuki
Published: July 2006

Phenyl-, furyl-, and 5-nitro-2-furylacrylonitrile oxides were prepared in situ from the corresponding hydroxamoyl chlorides and a base. They reacted with styrene or aery 1 amide as a dipolarophile to give the corresponding 3, 5-disubstituted isoxazolines in very low yields. These results show that the reactivity of such nitrile oxides was reduced by the presence of a conjugated double bond. Phenyl- and 5-nitro-2-furylacrylonitrile oxides were treated with α-morpholinostyrene to afford 3-styryl-5-morpholino-5-phenyl- and 3-(5-nitro-2-furylvinyl)-5-morpholino-5-phenylisoxazole respectively. The former product was further treated with hydrochloric acid to give 3-styryl-5-phenylisoxazole in a good yield. Phenylacrylonitrile oxide was heated in ethanol with cyanoguanidine, leading to 3-styryl-5-guanidino-1, 2, 4-oxadiazole. 5-Nitro-2-furylacrylhydroxamoyl chloride was treated with sodium azide to give the azido-aldoxime.
The Preparation of cis-3,4-Ureylenethiophane
Authors: Takaya Takao , Yoshimoto Hataaki , Imoto Eiji
Published: July 2006

The preparation of cis-3,4-ureylenethiophane (23) was attempted through three different routes. cis-3-Carbomethoxyamino-4-carbomethoxythiophane (20A), which had been obtained by the Lossen rearrangement of N-phenylsulfonyloxythiophane-cis-3, 4-dicarboximide (19), was selectively hydrolyzed to cis-3-carbomethoxyamino-4-carboxythiophane (21A), the modified Curtius rearrangement of which gave N-carbomethoxy-cis-3, 4-ureylenethiophane (22A). The alkaline hydrolysis of 22A afforded 23. However, an attempt to prepare 23 through two sulfone derivatives, (6) and (14), was unsuccessful.
Synthetic Studies of Bacitracin. III. Synthesis of (S)-2-(2-Methylbutyryl)-thiazole-4-carboxylic Acid and Its Peptide Derivative
Authors: Ariyoshi Yasuo , Shiba Tetsuo , Kaneko Takeo
Published: July 2006

An optical active 2-(2-methylbutyryl)thiazole-4-carboxylic acid obtained from bacitracin F by an acid hydrolysis was synthesized starting from l-isoleucine. Applying the usual methods for the peptide synthesis, 2-(2-methylbutyryl)thiazole-4-carbonyl-l-leucyl-d-glutamic acid α-methyl-γ-t-butyl ester corresponding to the N-terminal tetrapeptide of bacitracin F, was then synthesized from the thiazole carboxylic acid. UV spectrum of the synthetic tetrapeptide was very similar to that of bacitracin F.
The Ionic Telomerization of Conjugated Diene Compounds. III. The Effects of the Addition of Lewis Bases on the Cationic Telomerization of Butadiene with Its Hydrochlorides
Authors: Asahara Teruzo , Kise Hideo
Published: July 2006

The effects of the addition of several oxygen- and nitrogen-containing compounds on the cationic telomerizations of butadiene with its hydrochloride were investigated. The addition of both acetonitrile and ethyl ether to an ethyl bromide solution of ferric chloride or a methylene chloride solution of titanium tetrachloride resulted in large decreases in the catalytic activities of the solutions at low temperatures. On the other hand, the addition of nitroethane to an ethyl bromide solution of aluminum chloride increased the activity of the catalyst, although the addition of nitrobenzene decreased it. The addition of ethyl ether to ferric chloride or titanium tetrachloride led to the formation of telomers with lower molecular weights and larger degrees of unsaturation, whereas a nitroethane - aluminum chloride catalyst gave telomers with higher molecular weights. The monomolecular addition complexes of several Lewis acids and Lewis bases were isolated, and the catalytic abilities of the complexes in halogenated hydrocarbons were investigated. The structures of the higher telomers were analyzed and will be discussed.
ESR Studies of the Alkali Metal-Acenaphthene Ion Pairs
Authors: Iwaizumi Masamoto , Suzuki Masayasu , Isobe Taro , Azumi Hiroshi
Published: July 2006

Ion pairs formed by alkali metals with acenaphthene in ether-type solvents have been investigated by means of electron spin resonance (ESR). The ESR spectra of the ion pairs were found to show phenomena quite analogous to those found by de Boer et al. in the pyracene-alkali ion system; similar two-line-width alternation effects were also observed in the present work. These observations were contrary to the expectations formed by a consideration of the pyracenealkali metal ion pair, where the phenomena have been explained on the basis of the assumption that a potential well exists near the two ethylene bridges. This paper shows that, in the acenaphthene-alkali metal ion pairs, the alkali ion may be situated above the naphthalene skeleton rather than near the ethylene bridge. One of the line-width alternation effects is explained in terms of the exchange reaction between two ion-pair conformations in which the alkali ion is situated above and under the molecular plane respectively, while the other is ascribed to the oscillation of the cation in the potential well above either side of the molecular plane.
The Radiation Chemistry of Cyclic Dienes. III. The Effects of Electric Fields and Additives in the Radiolysis of 1,4-Cyclohexadiene Vapor
Authors: Nakagawa Tsunehiko , Takamuku Setsuo , Sakurai Hiroshi
Published: July 2006

In the γ-radiolysis of 1,4-cyclohexadiene vapor at room temperature, the contribution of neutral and ionic intermediates to the main products has been investigated by the application of electric fields and by the addition of nitrous oxide and ammonia as an electron and an ion scavenger respectively. It was suggested that the precursors of hydrogen, acetylene and 1,3-butadiene are exclusively the neutral excited molecules of 1,4-cyclohexadiene directly produced by the γ-irradiation, while those of the C6 products and polymer are mostly the ionic species. It was further derived that the contribution of neutralization reaction has little importance in the formation of hydrogen, acetylene and 1, 3-butadiene.
Hot Atom Chemistry of Phenylphosphorus Compounds
Authors: Kiso Yoshiyuki , Kobayashi Mitsue , Kitaoka Yoshinori , Kawamoto Keizo , Takada Jitsuya
Published: July 2006

A series of phenylphosphorus compounds, such as triphenylphosphine, triphenylphosphine oxide, triphenylphosphite, diphenylphosphite, tricresylphosphite, monophenylphosphate, triphenylphosphate, phenylphosphonic acid and phenylphosphonous acid, were irradiated in a nuclear reactor for 15–2100 min with a thermal neutron flux of 5×1012 n/cm2/sec. The relative amounts of the 32P-labeled gaseous products and the products soluble in an aqueous solution in the irradiated samples were then estimated. It was found that the compounds containing an oxygen atom bonded as P=O in a molecule had a tendency to yield the higher percentages of the products which were nonvolatile and soluble in an aqueous solution. The recoil products were separated into components by paper chromatography, and the chemical form of each component was identified. It was shown that the number of recoil products separated and the distribution of the chemical forms were greatly influenced by the chemical forms of the target compounds. The chemical reactions of the recoil 32P atom are also discussed, and a mechanism of the reactions which fits the experimental results is proposed.
Some Remarks on the Extended Hückel Approximation in the Independent-Electron MO Theory
Authors: Fukui Kenichi , Fujimoto Hiroshi
Published: July 2006

The sum of one-electron energies in the extended Hückel MO theory has been related to the total energy in the LCAO SCF MO theory including electron repulsion and nuclear repulsion terms. The sum of one-electron energies in the extended Hückel MO theory can be divided into the two parts; one almost independent of nuclear configuration and one highly sensitive to the configurational change. Of these the latter is found to be responsible for the stabilization energy due to the bond formation. The role of the highest occupied MO and the lowest unoccupied MO toward chemical reaction has been also discussed in the framework of the extended Hückel calculations. The partial AO population in these particular MO’s is shown to be almost valence-inactive one, being ready to be mobilized in case of chemical interaction with other systems.
A Simple Hückel Treatment of the Energy of Excimer Luminescence
Authors: Azumi Tohru , Azumi Hiroshi
Published: July 2006

The energy of the excimer luminescence is interpreted in terms of a simple Hückel-type dimer orbitals, which are constructed by treating the excimer as one species. The present model of the excimer yields results quite similar to those of the complicated ASMO CI treatment as developed earlier; further, it is capable of explaining various characteristics of the excimer, including the 6000 cm−1 rule.
The Synergistic Effect in Solvent Extraction—The Correlation of the Ionic Radius of Rare Earth Elements with the Stability Constants of Rare Earth Benzoyltrifluoroacetonate Adducts with n-Hexyl Alcohol, TBP and TOPO
Authors: Shigematsu Tsunenobu , Tabushi Masayuki , Matsui Masakazu , Honjyo Takaharu
Published: July 2006

The synergistic effects of n-hexyl alcohol, TBP and TOPO on the extraction of rare earth ions with benzoyltrifluoroacetone in benzene have been studied. The stability constants of the adducts were determined by means of the curve-fitting method. The equation based on the shift of pH1⁄2 (−ΔpH1⁄2) was also employed to analyse the data. The results were discussed in relation to the ionic radius of rare earth elements and summarized as follows: (1) The stability of rare earth benzoyltrifluoroacetonate decreases but that of the adducts increases, as the ionic radius increases. (2) The maximum number of base molecules bonding to one molecule of the metal chelate is 2, except that in the case of lutetium adduct with TOPO, where the formation of secondary adducts is not observed. (3) Although the overall stability constant of the adduct increases in the following order; lutetium < terbium < europium < lanthanum, as mentioned above, the first stability constant does not show such a distinct sequence. Therefore the contribution of the second stability constant seems to be an important factor. (4) Organic bases studied form stable adducts with rare earth benzoyltrifluoroacetonates in the following order; n-hexyl alcohol<TBP<TOPO. This order corresponds to the donating power of lone pair electrons of the oxygen atoms in these compounds.
Soluble Collagen of Chicken Leg Tendon; Its Denaturation Temperature and Hydrodynamic Properties
Authors: Sakai Rume , Ikeda Shoichi , Isemura Toshizo
Published: July 2006

The soluble collagen was extracted from chicken leg tendon with a 0.15 m citrate buffer at pH 3.8. The denaturation temperature was estimated to be 38°C by measuring the intrinsic viscosity and also by measuring the optical rotation at 589 mμ. The optical rotatory dispersion constants (λc) of collagen and gelatin were found to be 210±10 and 220±10mμ respectively. The intrinsic viscosity of collagen was 12.5±1.0 dl/g. The rotational diffusion coefficient at 20°C in water was 795±75 sec−1. The sedimentation constant at 20°C in water was 3.0S. From these data, the size and molecular weight of collagen were discussed. The collagen of chicken leg tendon is 2900 to 3000 Å in length and 12 to 16 Å in diameter, and has a molecular weight of 34×104.
Studies on Polymers from Cyclic Dienes. VI. Radiation Polymerization of the Thiourea Complex of Cyclopentadiene
Authors: Aso Chuji , Kunitake Toyoki , Ishimoto Yoshikazu
Published: July 2006

Cyclopentadiene was found to polymerize as its thiourea complex when irradiated with γ-rays from 60Co. The conditions of preparing the complex were an important factor in increasing the conversion, the use of 50 vol% aqueous acetone giving the best results. The polymer yield increased with dose and with temperature. The apparent activation energy of the polymerization was 2.7 kcal/mol. The poly cyclopentadiene thus obtained was concluded from its NMR and IR spectral data to have mainly the 1,4-structure.
Rheological Properties of Hydrogels of Agar-agar. II. Stress Relaxation of Concentrated Hydrogels
Authors: Watase Mineo , Arakawa Kiyoshi
Published: July 2006

A stress-relaxation experiment on hydrogels of agar-agar has been made over the range of concentration of about 3—11% by weight. A chainomatic balance relaxometer was used for the measurement of the relaxation Young’s modulus, and the temperature was varied over the range of about 20—70°C. The obtained relaxation curves have been analyzed using a mechanical model composed of three parallel Maxwell models. The relaxation times obtained for the gels of different concentrations at the same temperature have been found to be independent of the concentration. The elastic Young’s modulus, which may be attributed to the main network structure in the gels, has been found to be proportional to the 1.8 power of concentration. From the temperature dependence of the longest relaxation time, the activation energy for the relaxation process attributed to the destruction of junctions in the main network structure has been determined to be about 5 kcal/mol, irrespective of the concentration, over the whole range; this is of the order of the activation energy for the hydrogen bonds.
Effect of Molecular Vibrations on Gas Electron Diffraction. I. Probability Distribution Function and Molecular Intensity for Diatomic Molecules
Authors: Kuchitsu Kozo
Published: July 2006

General expressions and their practical approximations are presented for the molecular intensity of gas electron diffraction and the radial distribution function for an atom pair in the molecule which exerts moderately anharmonic intramolecular motion in thermal equilibrium. The calculations are based on a polynomial expansion of the probability distribution function of the internuclear distance around a Gaussian function representing harmonic vibration. The coefficients of the expansion for a diatomic system are calculated by the second-order perturbation method in terms of the coefficients of the potential energy expanded to the fourth order of the displacement in the internuclear distance. The structural parameters under various definitions (the mean internuclear distances, the mean square amplitudes, and the phase parameters) of a number of diatomic molecules are tabulated by the use of the spectroscopic values ωe, αe, and χe taken from the literature. The temperature dependence of the structural parameters is discussed.
The Crystal Structure of Bis(pyridine-2-carboxamido)nickel(II) Dihydrate
Authors: Nawata Yoshiharu , Iwasaki Hitoshi , Saito Yoshihiko
Published: July 2006

The orange-red, diamagnetic crystals of [Ni(pia)2]·2H2O (piaH: pyridine-2-carboxamide) have been subjected to X-ray crystallographic analysis. They are orthorhombic, space group Pm21b-C2v2, with two formula units in a cell of dimensions: a=7.61, b=20.19 and c=4.46 Å. The crystals consist of planar molecules in which Ni(II) exhibits a square planar coordination and the two ligands are coordinated to the central nickel atom with four nitrogen atoms in trans-configuration. The molecules are tilted about 40° with respect to the plane (001), and are piled up above one another along the c-axis to form columns. These columns are linked with each other by intermolecular hydrogen bonds of N–H···O type, thus forming layers parallel to the plane (010). The layers are piled up along the b-axis by way of two water molecules which are hydrogen-bonded to the oxygen atoms of the amide groups. There exist stacking faults along this direction.
Semi-Empirical SCF Molecular Orbital Treatment for Valence Electron Systems. I. Small Molecules
Authors: Yonezawa Teijiro , Yamaguchi Kaichiro , Kato Hiroshi
Published: July 2006

A semi-empirical SCF method for valence electron systems is presented. In the present method, the one-center integrals are estimated by means of the empirical values, while the two-center Coulomb integrals are calculated by the Ohno approximation. The other electronic repulsion integrals are evaluated by the Mulliken approximation. All overlap integrals in the secular equation are taken into account. By the present method, the electronic structures of several small polyatomic molecules are then studied. The calculated results are compared with the full SCF calculations and with the experimental values. The agreements between them are almost entirely satisfactory. The limitations of this method and the values of the parameters used are also discussed briefly.
Tracer Study of the Reactivity of Hydrogen Adsorbed on Nickel in the Hydrogenation Reaction
Authors: Takeuchi Toyosaburo , Miyatani Daisaku
Published: July 2006

The correlation between the bond strength of adsorbed hydrogen and the reactivity of the hydrogen toward ethylene has been investigated by using tritium as a tracer. Hydrogen (or tritium) was adsorbed first on powdered nickel at −78°C; tritium (or hydrogen) was subsequently adsorbed, and then ethylene was added. The total coverage of hydrogen in every experiment was 0.16 or 0.4 for the nickel reduced at 200°C, and 0.06 or 0.4 for the nickel reduced at 400°C. After a certain time, the hydrogen and the mixture of ethane and ethylene were drawn off successively from the reaction vessel and separated. An assay of the tritium in each fraction of the gas was then made. The results on the nickel reduced at 200°C indicate that neither the very-strongly-adsorbed hydrogen nor the weakly-adsorbed hydrogen reacts with ethylene. The results on the nickel reduced at 400°C indicate that the weakly-adsorbed hydrogen does not react with ethylene either. These findings suggest that the very strong sites for the adsorption of hydrogen, which are inactive in the hydrogenation, are diminished by the elevation of the reduction temperature.
The Oxidation of α-Methylstyrene in the Presence of Benzaldehyde
Authors: Niki Etsuo , Kamiya Yoshio
Published: July 2006

The oxidation of α-methylstyrene in the presence of benzaldehyde was studied at 40°C, with and without added metal salt catalysts, from the viewpoint of the products obtained. The products were α-methylstyrene oxide, acetophenone, formaldehyde, α-methylstyrene polyperoxide, perbenzoic acid, and benzoic acid; few side reactions between these products were observed under the reaction conditions employed here. Emphasis was laid on the effect of metal salt catalysts and of the initial composition of the oxidants on the cleavage products from α-methylstyrene. Manganese and copper salts were found to have little effect, while cobalt salt showed a characteristic effect on the formation of the cleavage products. In the presence of cobalt salt, the formation of acetophenone was accelerated. The increase in the formation of α-methylstyrene oxide in this system compared with the oxidation of α-methylstyrene alone may well be attributed to the polar reaction of α-methylstyrene with perbenzoic acid formed from benzaldehyde. The consumption of perbenzoic acid in various systems was also examined. The increase in the initial concentration of benzaldehyde increased the yield of α-methylstyrene oxide and decreased that of acetophenone.
Asymmetric Synthesis with Sugar Derivatives. II. Asymmetric Syntheses by Methoxy-Mercuration of Cinnamic Esters of Sugar Derivatives
Authors: Kawana Masajiro , Emoto Sakae
Published: July 2006

The methoxy-mercurations of cinnamic esters of 1, 2; 5, 6-di-O-isopropylidene- and -cyclohexylidene-d-glucose, 5-deoxy-1, 2-O-isopropylidene-d-xylose, (−)-menthol, and (+)-borneol with mercuric acetate in methanol, followed by the reductive demercuration of the 3-acetoxymercuri-2-methoxyhydrocinnamic esters with sodium borohydride, gave, after the hydrolysis of the demercurated esters, IV, with alkali, 3-methoxy-3-phenylpropionic acid (V) in 1—27% optical yields, depending on the methoxy-mercuration time. When the methoxy-mercuration time was extended, the specific rotation of V decreased, but there was no corresponding decrease in the synthetic yield in the presence of nitric acid as a catalyst. This shows that an equilibrium in the methoxy-mercuration has been completed. The demercurated esters, IV, were reduced with lithium aluminum hydride to afford 3-methoxy-3-phenylpropan-1-ol (IX) in 6—22% optical yields. The absolute configurations of both V and IX were established to be (S)(−)-configurations. In the methoxy-mercuration, it seems likely that no oxygen atoms of sugar derivatives act as a co-ordinating group to keep the acetoxymercuri-group onto one side of the carbon-carbon double bond of cinnamate.
The Effect of Substituents in Radical Reactions: Reactivities of Substituted Cumenes to Attack by the Polystyryl Radical
Authors: Yamamoto Tadahiro
Published: July 2006

The polymerizations of styrene in a series of nuclear-substituted cumenes, using α, α′-azobisisobutyronitrile as an initiator, have been carried out at 60°C, and the chain transfer constants, Cs, for the substituted cumenes have been determined. It has been found that the Cs values for cumenes with electron-repelling groups are smaller than that for an unsubstituted cumene, while those for cumenes with electron-attracting groups are greater. The plot of log (k⁄k0) against the corresponding Hammett’s σ-constants failed to give a linear relationship. The modified Hammett’s equation including the resonance effect for radical reactions, the equation which was proposed by the author and Azumi, i.e.,: log(k⁄k0)=ρσ+γER, could be adopted to the transfer with the usual precision, giving γ=1 and ρ=0.7. It is considered that the effects of substituents on the transfer reactivities of cumenes to the attack of the polystyryl radical depend on the contributions of polar and resonance factors.
The Synthesis and the Thermal Decomposition of 1, 3, 4-Dioxazole Derivatives
Authors: Nohira Hiroyuki , Inoue Kenji , Hattori Hirotoki , Okawa Toji , Mukaiyama Teruaki
Published: July 2006

2, 2, 5-Tri-substituted-1, 3, 4-dioxazoles have been prepared by the reactions of benzhydroxamic acids with the diethylketals of such ketones as acetone, cyclohexanone, acetophenone and benzophenone. These dioxazoles decompose at elevated temperatures (above 150°C) into phenylisocyanates and ketones. A kinetic study of the decomposition reaction in nitrobenzene has been attempted, and the first-order rate constants have been obtained.
Kinetische Untersuchung über die durch Triphenylmethyl induzierte Zersetzung von Benzoylperoxyden
Authors: Suehiro Tadashi , Kanoya Akio , Hara Humihiro , Nakahama Tetsuro , Omori Muneki , Komori Tsuneo
Published: July 2006

Die Geschwindigkeiten der Umsetzung von m, m′- und p, p′-symmetrisch substituierten Benzoylperoxyden mit Triphenylmethyl in aromatischen Lösungsmitteln wurden durch Messung der Abnahme der Absorption vom Triphenylmethyl bei 15–35°C bestimmt. Die Umsetzung von Peroxyd in Benzol wird durch die Elektron Acceptor Substituenten beschleunigt (rho=+1.45, r=0.975) und die isokinetische Temperatur ist ca. 180°K. Die Reaktionsgeschwindigkeit von Peroxyd mit Triphenylmethyl wird wieder durch die Polarität der aromatischen Lösungsmitteln beschleunigt und bei dem nicht substituierten Benzoylperoxyd erhält man die isokinetische Temperatur von ca. 390°K. Daraus. wird geschlossen, dass im Übergangszustand polaren Strukturen eine grosse Rolle spielen.
An X-ray Study on the Phase Transition of Phenanthrene Crystal
Authors: Matsumoto Shoichi , Fukuda Tsuguo
Published: July 2006

The presence of a higher-order phase transition at around 60–70°C in phenanthrene crystal, previously suggested by the anomalies in electrical conductivity and in thermal expansion, and by the endothermic phenomenon, has been confirmed through an X-ray powder diffraction study. The results disclose the following facts: (1) the phenomena of the transition begin about 45°C and gradually become remarkable with a rise in the temperature, until the phenomena practically cease to occur at 68–69°C; (2) the lattice constants for the monoclinic cell increase conspicuously in the temperature range from about 50°C to 68°C, while both the crystal system, which is monoclinic, and the space group, P21, remain unaltered on passing through the transition temperature, and (3) the unit cell dimensions of the high-temperature modification determined at 80°C are: a=8.54, b=6.25, c=9.55 Å and β=99.0°.
Oxidative Polymerization of Polybutadiene and Its Derivatives
Authors: Chen Leo-Wang , Nemoto Tsuguo , Kumanotani Ju
Published: July 2006

The oxidative polymerization or peroxide curing for such prepolymers as polybutadiene consisting mainly of 1, 2-structure, or esters containing the butadiene units was studied by means of infrared spectral analysis and dynamic mechanical measurements. Films of the cross-linked polybutadiene formed by the oxidative polymerization reaction show a high glass transition temperature and a high degree of crosslinking. This is considered to be the result of the larger amount of double bonds that are involved in the prepolymers and which suffer cross-linking, and the result of the presence of such polar groups as those of carboxyl, carbonyl and hydroxyl groups in the dried film, which are formed in the course of oxidative polymerization. When t-butylperbenzoate was used as a catalyst for cross-linking polybutadiene, some cyclization of vinyl groups was observed, leading to a less effective cross-linking. A greater reactivity was observed for trans-ethylenic double bonds than for vinyl groups in these reactions. Polybutadiene, being of larger molecular weight, gave a film of a higher (Tg)d value.
Dielectric Constants of Solid 1, 1, 1, 2-Tetrachloro-2-methylpropane and Solid 2-Bromo-1, 1, 1-trichloro-2-methylpropane
Authors: Koide Tsutomu , Oda Tsutomu , Masuda Hisashi , Uchihashi Hiroshi
Published: July 2006

A newly-devised electrode cell for the measurement of the dielectric constant of plastic crystals was described. By the new electrode cell, the dielectric constants of Cl3C–C(CH3)2Cl and Cl3C–C(CH3)2Br were measured for the temperature range from −170°C to 80°C. The values of the dielectric constant changed sharply at the phase transition points. The changes in the dielectric constants at the phase transition points indicate that the transition is a rotational one.
Comparative Measurements of Combined Residual Chlorine around the Break Point
Authors: Isomura Yutaka
Published: July 2006

Recent development of analytical method for the combined residual chlorine enables us to identify individual content of mono-, di-, and tri-chloramine together with that of free available residual chlorine in ppm order. Applying both amperometric titration method and Palin method, comparative measurements of these chloramines gave us some insight into the mechanisms of the break point where residual chlorine decreases remarkably despite of the increasing addition of chlorine to the treating water in which ammoniacal nitrogen or albuminoid nitrogen is contained in a few ppm. Basic study of the break point became necessary to carry out faultless operation of a full automatic controlled chlorination plant by the break point chlorination process by making residual chlorine recorders and Venturi-tubes as the transmitters of control signals. The system maintains constant amount of free residual chlorine at the effluent irrespective of the amount of ammoniacal nitrogen and the amount of water to be treated by the plant should change at random. Suggestions are given to the mechanisms of the break point and the reaction mechanisms are discussed for the appearance and disappearance of chloramines from the measured results.
The Kinetics of Substitution Reactions Involving Metal Complexes. X. Reactions of Zinc(II) with Ethylenediaminetetraacetatocobaltate(II) and Trimethylenediaminetetraacetatocobaltate(II)
Authors: Ogino Hiroshi , Tanaka Nobuyuki
Published: July 2006

Kinetics of the substitution reactions of zinc(II) with ethylenediaminetetraacetatocobaltate(II) and with trimethylenediaminetetraacetatocobaltate(II) have been studied. These reactions proceed predominantly through three simultaneous reaction paths, of which two involve electrophilic substitution reactions and the rest does the dissociation reaction of the complex. The rates of the reactions involving trimethylenediaminetetraacetatocobaltate(II) are larger than those involving ethylenediaminetetraacetatocobaltate(II) for all of the three simultaneous reaction paths. These results are discussed on the basis of the nature of the ligands and the stability of reaction intermediates.
Kinetics of Selenium Spherulite Growth
Authors: Hamada Shuichi , Sato Tadao , Shirai Toshiaki
Published: July 2006

The growth rates of spherulites of selenium were estimated by the photomicrographic method in the temperature range from 80°C to 120°C. The selenium was used in the pure and the chlorinated states. At a constant temperature, the spherulite radius increased at a constant rate. The growth rate for pure selenium, logG, varied linearly with 1/T, and the apparent activation energy for growth, EA was estimated to be 24.9 kcal/mol. The apparent activation energy for growth is much larger than that for the transport of the chain molecule, which was estimated from the activation energy for the viscous flow. The linear variation in the growth rate, logG, with 1/T appeared at temperatures well below the melting point of crystalline selenium, and the apparent activation energy for growth was nearly equal to the enthalpy change for the thermal equilibrium of the opening reaction of the Se8 ring molecule. These facts indicate that the selenium spherulite growth is not a diffusion-controlled process, but a breaking process of the Se-Se bond in the chain molecule. Moreover, the mechanism of growth at the amorphous-crystalline interface was considered with regard to the variation in the growth rate, in the apparent activation energy for growth, and in the activation entropy change against the chlorine content.
Synthesis and Properties of Surface Active Organotitanium Compounds. I
Authors: Ochi Miyoko , Yoshino Takeshi , Meguro Kenjiro
Published: July 2006

An entirely new series of surface-active polyethenoxy titanium esters which can be prepared by reactions with tetraalkoxy titanium and various polyoxyethylene higher alkyl ethers have been developed. The new series of the titanium compounds are nonionic surface-active agents and have the following general formula: Ti[O(CH2CH2O)nR′]4 (the R′ value is higher alkyl radicals). The compounds are viscous liquids or waxy solids; they are soluble in various organic solvents, and some of them are soluble in water. These compounds have dispersing power on titanium oxide in aqueous and non-aqueous media. In this paper, the preparation and properties of these compounds will be described in comparison with the usual nonionic surface-active agents.