bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Double Cycloaddition of Disulfene and Its Related Reactions
Authors: Hirai Koji , Tokura Niichiro 
Published: July 2006

Abstract
The reactions of methanedisulfonyl chloride (II) with ketene diethylacetal (III), 1 -morpholinocyclohexene (IV), and 1-piperidinopropene (V) in the presence of triethylamine were studied. The products obtained were the double cycloadduct, spiro bithietane tetroxide (VI), and the substitution products (X and XV). These findings suggest that triethylamine dehydrochlorinates methanedisulfonyl chloride to produce disulfene. However, as yet we cannot say whether the formation of disulfene is the one-step dechydrochlorination mechanism (ClSO2CH2SO2Cl → SO2=C=OS2) or the two-step one (ClSO2CH2SO2Cl → ClSO2CH=SO2 → SO2=C-SO2).
Addition of Tellurium Tetrachloride to Olefins and Pyrolysis of the Adduct
Authors: Ogawa Masao , Ishioka Ryoji 
Published: July 2006

Abstract
The tellurium tetrachloride-cyclohexene adduct, 2-chlorocyclohexyltellurium trichloride (I) and bis(2-chlorocyclohexyl) tellurium dichloride (II), both gave, on pyrolysis, chlorocyclohexane as the chlorinated compound. An intermolecular hydrogen transfer is required for the formation of chlorocyclohexane from I. Chloro-n-propyltellurium trichloride (III) and bis(chloro-n-propyl)-tellurium dichloride (IV) were formed by the addition of tellurium tetrachloride to propylene. The pyrolysis of III afforded allyl chloride, 1,2-dichloropropane, and hydrogen chloride, while tellurium was simultaneously reduced. Besides these products, isopropyl chloride was also obtained from IV. Some properties of the adduct and the effect of the temperature on the thermal decomposition were studied.
Aromatic Sulfonylation. II. Attacking Species under Various Conditions.
Authors: Kohara Yoshio , Kobayashi Michio , Minato Hiroshi 
Published: July 2006

Abstract
p-Toluenesulfonylation of toluene and anisole in the presence of AlCl3, SbCl5 or TiCl4 was investigated in methylene chloride, nitromethane and nitrobenzene. Substitution took place at 8.6–13.4% and 86.6–91.4% para positions for toluene in methylene chloride, but 42.0–45.7% ortho and 54.2–58.0% para isomers were obtained in nitromethane and nitrobenzene. Sulfonylation of toluene with p-CH3C6H4SO2+ ClO4− afforded 44.8–46.3% ortho and 53.7–55.2% para isomers. Partial rate factors for toluene were pf=52.5 in methylene chloride, of=12.6±0.9, pf=31.4±2.0 in nitromethane, and of=16.0±1.7, pf=38.3±4.2 with p-CH3C4H4SO2+ClO4−. A plausible mechanism is proposed, in which the attacking species is TsCl-MCln complex in methylene chloride, but it is an ion pair, ArSO2+MCl−n+1, in nitromethane and nitrobenzene.
Measurement of the Adsorption of Tritium Labelled Sodium Stearate at Air/Water Interface using Thin Windowed Geiger-Müller Counter Tube
Authors: Sekine Keiichi , Seimiya Tsutomu , Sasaki Tsunetaka 
Published: July 2006

Abstract
The adsorption of tritium labelled sodium stearate at various pH values and temperatures was directly measured by using a thin end-windowed Geiger-Müller counter. The disturbances due to the application of high electrical potential and the introduction of counting gas were avoided, which are inevitably encountered in an ordinary windowless 2π counter. Precautions were taken to avoid both surface evaporation effect and contamination of solution due to the absorption of carbon dioxide from the air. The results show that free stearic acid is considered to be the main surface active species in an aqueous sodium stearate.
Electronic Structures and Electronic Absorption Spectra of Cyclohexadienyl and Related Radicals Produced by γ-Irradiation
Authors: Shida Tadamasa , Hanazaki Ichiro 
Published: July 2006

Abstract
The electronic absorption spectrum for the cyclohexadienyl radical produced upon γ-irradiation of pure benzene and benzene-alcohol solutions both at 77°K was investigated. In addition to the absorption band at 3.9 eV, a weak band with a prominent vibrational structure was observed at 2.2 eV. An SCF-CI molecular orbital calculation was carried out for the radical taking into account explicitly the hyper conjugation effect of methylene group. The theory predicts the two observed bands with satisfactory accuracy. The calculated spin densities are also in good agreement with the existing ESR data of the radical. Vibrational analysis was carried out for the band system at about 2 eV as well as for the corresponding bands of isotopically mixed radicals, C6H6D, C6D6H, and C6D7. Parallel calculations for hydronaphthyl radicals are also in harmony with the available experimental data of optical and ESR measurements.
The Photochemical Rearrangements of N-Acetyl Diphenylamine and N-Acetyl Carbazole
Authors: Shizuka Haruo , Kato Motonobu , Ochiai Toshio , Matsui Kohji , Morita Toshifumi 
Published: July 2006

Abstract
The photochemical reactions of N-acetyl diphenylamine and N-acetyl carbazole in solution have been studied. N-Acetyl diphenylamine and N-acetyl carbazole undergo the photo-Fries-rearrangement by means of 2537Å irradiation. The reaction products consist of the ortho- and para-isomers, plus corresponding amines transformed through the deacetylation of the original compounds. The quantum yields in the early stages of the rearrangement were measured under various conditions by spectrophotometry. The reaction mechanism has been discussed on the basis of the relation between the rate constants of the rearrangement and the odd π electron densities obtained from simple Hückel MO calculations.
Kinetics of the Ligand Substitution Reaction of the Copper(II)-4-(2-Pyridylazo)resorcinol Complex with (Ethylene glycol)-bis(2-aminoethyl ether)-N,N,N′,N′-tetraacetic Acid
Authors: Funahashi Shigenobu , Yamada Shinkichi , Tanaka Motoharu 
Published: July 2006

Abstract
The kinetics of the ligand substitution reaction of the copper(II)-4-(2-pyridylazo)resorcinol complex (Cu(II)-PAR) with (ethylene glycol)bis(2-aminoethyl ether)-N,N,N′,N′-tetraacetic acid (EGTA) has been studied spectrophotometrically at pH 9–10 at μ=0.10 (NaClO4) and at 25.0°C. The reaction proceeds through the 1:1 Cu(II)-PAR complex resulting from the predissociation equilibrium of the 1:2 Cu(II)-PAR complex:
-d[CuR_2^2-]/dt=10^6.15[CuR_2^2-][H^+][Y’]/[HR^-]=10^2.9[CuR][Y’]
where R2- refers to the divalent anion of PAR (H2R) and Y′ the free EGTA not combined with any metal. The release of PAR from the mixed ligand intermediate RCuY is the rate-determining step. The substitution reaction for the copper(II)-PAR complex proceeds in the same mechanism with that for the zinc(II)-PAR complex. The difference in reactivity of these complexes is discussed. Cu-PAR bond is weakened in a distorted octahedron of the intermediate RCuY before the release of PAR.
Photochemical Studies of the Esters of Aroylphosphonic Acids
Authors: Terauchi Ken-ichi , Sakurai Hiroshi 
Published: July 2006

Abstract
The photochemical behavior of several dialkyl benzoylphosphonates and para-substituted benzoylphosphonates in various solvents has been studied using product isolation, ultravioletspectral change, the electron spin resonance (ESR) technique, and quantum yield measurements. Upon irradiation to a degassed solution of these benzoylphosphonates through a Pyrex filter, the photo-pinacolization reaction was observed, except in the case of diethyl benzoylphosphonate; it was effectively quenched by 1,3-pentadiene or oxygen. On the other hand, the ESR spectra of photo-irradiated aroylphosphonates at 77°K have a large anisotropic doublet of 53–128 gauss separation; this separation is thought to be due to the interaction between an unpaired electron and the phosphorus nucleus. The structure of these radicals is also discussed. From these observations, it can be considered that the photochemical reaction proceeds via the ketyl radical formed by the hydrogen abstraction of the lowest excited triplet state of these aroylphosphonates. Irradiation to the diethyl benzoylphosphonate solutions in various solvents gave, not the pinacolized product, but 2,4,6-triphenyl-2,4,6-tris[diethylphosphoryl]-1,3,5-trioxane almost quantitatively. The quantum yields (Φ) of the disappearance of several para-substituted derivatives are highly sensitive to the electron-inductive abilities of the substituents; that is, Φ drops from 2.10 in the p-methoxybenzoylphosphonate derivative to 1.79 in the p-chloro derivative at room temperature. Such a substituent effect can be considered to result in the difference in the conformation between the carbonyl and phosphoryl groups. On the basis of these studies, the mechanism of the photochemical reaction of aroylphosphonates is described and discussed.
Studies of Peptide Antibiotics. XV. The Synthesis of cyclo-(l-Valyl-l-ornithyl-l-leueyl-d-phenylalanyl-l-prolyl-glycyl-glycyl)
Authors: Abe Okitoshi , Kuromizu Kenji , Kondo Michio , Izumiya Nobuo 
Published: July 2006

Abstract
A cyclic heptapeptide, cyclo-(l-Val-l-Orn-l-Leu-d-Phe-l-Pro-Gly-Gly-), was synthesized in order to investigate a contribution for an antibacterial activity of a ring size of a cyclic peptide. A linear heptapeptide p-nitrophenyl ester, in which an δ-amino function of ornithine residue was protected with benzyloxycarbonyl group, was transformed to the cyclic benzyloxycarbonyl-substituted heptapeptide which was hydrogenated to afford the desired cyclic heptapeptide as hydrochloride. The cyclic peptide thus obtained showed no activity against any of microorganisms tested.
The Emission Spectra of Hydrogen Atoms Produced from Methanol by Electron Impact
Authors: Fujita Iwao , Hatada Motoyoshi , Ogawa Teiichiro , Hirota Kozo 
Published: July 2006

Abstract
The emission spectra of several fragmental species, especially of hydrogen atoms, produced by the electron impact (energy:240 eV) of gaseous methanol and deuteromethanols have been investigated. The intensity ratios of the Balmer-β lines of the H and D atoms are ca. 2.9:1 for CH3OD and ca. 1:1.8 for CD3OH, indicating that the excited hydrogen atoms result from the O–H bond scission, as well as from the C–H bond scission, of the parent methanol molecules. The ratio of the scission probability of a C–H bond to that of the O–H bond is calculated to be 0.8, taking into account the correction of the isotope effect. It was concluded that the excited hydrogen atoms are produced by the primary process of fragmentation via a superexcited species.
Electron-Transfer Reactions of Multidentate Ligand Cobalt(III) Complexes. II. The Effect of Nonbridging Ligands
Authors: Kurimura Yoshimi , Ohashi Kousaburo 
Published: July 2006

Abstract
The specific rates for the Fe2+ reductions of cis-Co(en)2ACl2+ (A=methyl-, ethyl-, propyl-, butyl-, ethanol-, and propanolamine), Co(dien)(en)Cl2+ and Co(tetren)Cl2+ have been determined. The observed rates are relatively insensitive to the cis-ligand of the A. The rate constant for the cis-Co(en)2ACl2+ decreases with an increase in the size of the A ligand. In such cases as that of the aminoalcohol ligand, the rate is greater than that of the corresponding alkylamine ligand complex. The effect of chelation by nonbridging ligands has been discussed by comparing the relative effectiveness for Fe2+ reductions of CoN5Cl2+ (N5=(NH3)5, (en)2NH3, (dien)(en), and tetren) with that for Cr2+ reductions of some Co(III) complexes.
The Preparation and Reactions of Benzoylnitrile Oxide from Dimethylphenacylsulfonium Bromide
Authors: Otsuji Yoshio , Tsujii Yasuhiro , Yoshida Akihiko , Imoto Eiji 
Published: July 2006

Abstract
The nitrosation of dimethylphenacylsulfonium bromide (I) with sodium nitrite and hydrochloric acid in water gave 3,4-dibenzoyl-1,2,5-oxadiazole 2-oxide (II) in a 76% yield. The nitrosation of I in a similar manner in 1 : 1 dioxane-water afforded ω-chloro-ω-isonitrosoacetophenone (III) in an 80% yield. The treatment of III with triethylamine produced II through benzoylnitrile oxide (IX). 1,3-Dipolar cycloadditions of IX generated from III were conducted, using methyl methacrylate, styrene, acrylonitrile, and ethyl chloroformate as dipolarophiles, to yield the expected cycloadducts. The mechanisms of these reactions are discussed.
A General Matrix Method for Treating Elastic Constants of Molecular Crystals; Application to Orthorhombic Polyethylene
Authors: Shiro Yuji , Miyazawa Tatsuo 
Published: July 2006

Abstract
A general method is developed for treating elastic constants of molecular crystals, with the B matrices as commonly used in normal-coordinate treatments. Equations are written in matrix forms, convenient for calculating elastic constants from intramolecular and intermolecular force field and are readily programed for electronic computations. Partial derivatives of elastic constants with respect to force constants are also derived, for least-square adjustments of force fields with reference to experimental elastic constants as well as vibrational frequencies. Matrix treatments of elastic constants are much simplified by the use of crystal symmetry, just as are treatments of normal vibrations. The matrix methods are explained for the example of orthorhombic polyethylene.
The Mechanism of Vinyl Polymerization by Dialkylbis(dipyridyl)iron(II)
Authors: Yamamoto Takakazu , Yamamoto Akio , Ikeda Sakuji 
Published: July 2006

Abstract
Kinetics of polymerization of vinyl compounds (acrylonitrile, methacrylonitrile, acrolein, methyl vinyl ketone, methyl acrylate, alkyl methacrylates, and 2-vinylpyridine) with dialkylbis(dipyridyl)iron(II), FeR2(dipy)2 1 (R=CH3, C2H5, n-C3H7), was studied. By comparison with previous kinetic results in which the decomposition of 1 was followed spectroscopically, a polymerization mechanism including a slow initiation process followed by rapid propagation and unimolecular termination processes was proposed. The effects of the concentration of monomer, the addition of dipyridyl and the coordinating ability of solvent on the molecular weight of the polymer were explained by competitive coordination to the iron complex having a growing polymer chain. Results of copoly-merization experiments were explained in terms of competitive coordination and insertion reactions between the monomers involved. A linear relationship was found between log(1⁄r1) values and the logarithms of stability constants of nickel-olefin π-complexes with methacrylonitrile as the reference (M1). From the formation of C2-H5D in the polymerization of β-cis-d1-methyl methacrylate with Fe(C2H5)2(dipy)2 a unimolecular termination process involving abstraction of β-hydrogens of the growing chain by the alkyl group or the iron complex was proposed.
Nitrate as an Oxidant in the Reaction of Silver(I) Salts with Grignard Reagents
Authors: Tamura Masuhiko , Kochi Jay K 
Published: July 2006

Abstract
The reaction between various Grignard reagents and silver(I) salts in the presence of nitrogen-containing oxidants such as lithium nitrate, nitrogen dioxide, and methyl nitrate has been examined in tetrahydrofuran solutions. Coupling dimer is formed in high yields almost independently of the structure of the Grignard reagent. From the stoichiometry, it is concluded that these oxidants oxidize two equivalents of metallic silver formed in situ to silver(I) species under proper reaction conditions. Other transition metal halides are also oxidized by these oxidants in a similar manner. Soluble forms of reduced silver complexes formed in the reaction of silver(I) nitrate and Grignard reagent are also described.
The Substituent Effect. III. The Basicities of Polynuclear Aryl Methyl Ketones
Authors: Yukawa Yasuhide , Tsuno Yuho , Sawada Masami 
Published: July 2006

Abstract
The basicities of nine polynuclear aryl methyl ketones have been determined spectrophotometrically in various aqueous sulfuric acid solutions. The electronic effects of unhindered polynuclear aryls on pKBH+ can be successfully correlated with our LArSR equation,
logk⁄k0=ρ(σ0+rΔ\barσ\overset+R),
using ρ and r values established from meta- and para-substituted acetophenones. The applicability of this equation to polynuclear aryls is also shown for some other electrophilic reactivities. The Δ\barσ\overset+R parameters for polynuclear aryls are derived empirically from the solvolysis of α-arylethyl chlorides; these show a good linearity with the theoretical reactivity indices of the localization energies.
Aminosugars. XIX. On the Structure of 2-Deoxy-2-guanidino-d-glucose
Authors: Yoshimura Juji , Sekiya Tetsuo , Iida Takao 
Published: July 2006

Abstract
It was found that 2-deoxy-2-guanidino-d-glucose prepared by guanidination of 2-amino-2-deoxy-d-glucose with cyanamide exists mainly as α-d-glucofurano[1′,2′;4,5]-2-imino-imidazolidine (5) which is easily converted into 2-imino-4-(d)-arabino-tetrahydroxybutyl)imidazoline-4 (6) under alkaline conditions. Acetylation of 5 and 6 gave the corresponding hexa- and heptaacetate (7 and 8), respectively. Warming of 7 in alcohols gave addition compounds of alcohols to the imino double bond, and deacetylation with sodium alcoholate at a room temperature yielded 2-acetamido-4-(d-arabino-tetrahydroxybutyl)imidazole (10). Similar treatment of 8 in ethanol at elevated temperature gave an unknown addition compound in which two N-acetyl groups were eliminated, and deacetylation with a small amount of sodium methylate yielded a mixture of (2R,S)-2-acetamido-2-methoxy-4-(d-arabino-tetraacetoxybutyl)imidazoline-4 and tetra-O-acetyl derivative of 10 which was also obtained by acetylation of 10.
The Isomerization of Propylene Oxide on Metal Phosphate Catalysts
Authors: Imanaka Toshinobu , Okamoto Yasuaki , Teranishi Shiichiro 
Published: July 2006

Abstract
The isomerization of propylene oxide was carried out on metal phosphate catalysts. The main products were allyl alcohol, propionaldehyde, acetone, and 1-propanol. It was found that allyl alcohol is produced by acid-base bifunctional catalysts, acetone, by basic-site catalysts only, and propionaldehyde, by acid-site catalysts. 1-Propanol may be produced by the hydrogen-transfer reaction of allyl alcohol. The conversion to propionaldehyde is proportional to the acidity of the catalyst, the strength of which is stronger than H0=+4.8. The sum of the conversions to allyl alcohol, acetone, and 1-propanol correlate linearly with the observed basicity (H0≥+7.2) of the catalyst. The selectivity and activity are determined by the basic and acidic properties of the catalyst. The mechanisms of the propylene oxide isomerization are also discussed.
The Crystal and Molecular Structure of Bis(l-prolinamidato)-nickel(II) Dihydrate
Authors: Tsukihara Tomitake , Katsube Yukiteru , Fujimori Kumiko , Ishimura Yoshihisa 
Published: July 2006

Abstract
The crystal structure of bis(l-prolinamidato)nickel(II) dihydrate has been determined by three dimensional X-ray analysis. The crystals are vermilion needles and belong to the space group P21. The unit cell has dimensions a=10.915, b=7.319, c=9.445 Å, β=112.6° and contains two structure units. The structure has been solved using Patterson synthesis, minimum function and Fourier synthesis and refined by diagonal and blockdiagonal least-squares methods on 1115 independent reflections. The final R value was 0.054. The nickel atom exhibits square planar coordination. Two proline-amide molecules are approximately related to each other by a two fold axis and these two ligand molecules coordinate to the central nickel atom in trans form. The oxygen atom of water does not coordinate to the nickel atom.
The Nitration of Nickel(II)-, and Copper(II)-complexes of Bis(salicylaldehyde)ethylenediimine
Authors: Tamaki Motonori , Masuda Isao , Shinra Koichiro 
Published: July 2006

Abstract
The M(Salen) complexes (where M=NiII, CuII, CoII-NO, and VIVO, and where Salen=bis(salicylaldehyde)-ethylenediiminato dianio) were reacted with nitric oxide in organic solvents in the air. The free ligand can only form a compound with the formula of SalenH2·2HNO3, while the complexes with M=Ni or Cu gave NO2-substituted complexes, M(5,5′-dinitro-Salen), in almost quantitative yields. In the cases of Co(Salen)NO and VO-(Salen), no substitution reaction on the phenyl ring took place, but they formed a nitric acid adduct, Co(Salen)NO·nHNO3·nH2O(n=1 and 2) and VO(Salen)·HNO3·H2O. The reactions are thought to proceed by means of a process involving a nitric acid. The reactivity of the Ni- and Cu-Salen complexes is explained in terms of a π-electron localization at the 5- and 5′-positions of the phenyl rings resulting from dπ→pπ back bonding. A lack of a similar substitution reaction in Co(NO)- and VO-Salen complexes is explained as being due to the lower stability in the metal-Salen bonding.
Trace Analysis of Metals by ESR. III. Determination of Silver by Solvent Extraction with Tetraethylthiuram disulfide Silver(II) Complex
Authors: Yamamoto Daijiro , Ozeki Fumiaki 
Published: July 2006

Abstract
A new method was worked out for the determination of silver using ESR. Bivalent complex of silver with tetraethylthiuram disulfide extracted with carbon disulfide, benzene, carbon tetrachloride, xylene, ethylbenzene, toluene, chloroform, and organic solvents was stable. The complex in carbon disulfide gave a very strong ESR signal, the sensitivity being 0.1 ppb. The amount of solution required was 1 ml. Colorimetric method can also be applied. However, the sensitivity was lower than that of ESR method. Silver was determined photometrically at 620 nm as a complex with tetraethylthiuram disulfide. The absorption followed Beer’s law in the range 10–100 ppm of silver concentration at 620 nm. Bivalent silver complex could be selectively extracted in the presence of several ions, except copper(II) and mercury(II). Results of the continuous variation method indicate that the silver(II)-tetraethylthiuram disulfide ratio in the complex is 1 : 1.
The n-π* Absorption and Phosphorescnce of Terephthalaldehyde
Authors: Murakami Yoshio , Shimada Ryoichi , Kanda Yoshiya 
Published: July 2006

Abstract
The n→π* absorption spectrum of terephthalaldehyde (TPA) has been studied. The fn→π*-value observed in cyclohexane at room temperature was 1.3×10−3, which was 2.4 times that of benzaldehyde (BA). Vibrational analyses of the absorption and phosphorescence spectra of TPA indicate that the CHO-torsional, CHO-wagging, aldehyde H-wagging, and out-of-plane ring deformation vibrations are important in the vibronic perturbation between (n,π*) and (π,π*) states. The spectral structures and the results of CNDO computations of the fn→π*-values of the n→π* absorptions of TPA and BA suggest that the intensity enhancement in the TPA absorption is due to an increase in the vibronic perturbation between (n,π*) and (π,π*) states as well as to an increase in the electronically-allowed character in TPA in comparison with that in BA.
Mass Spectrometric Analysis of Water-insoluble Yellow Monoazo Pigments
Authors: Kobayashi Kousuke , Hirose Kazutoyo 
Published: July 2006

Abstract
Water-insoluble Yellow Monoazo Pigments were examined in order to establish a new analytical system using mass spectrometry. The characteristic ions observed were as follows: molecular ions, amine-component ions which are formed by the scission of the amide bond with hydrogen transfer and which are the most intense ones, ions at m⁄e: 43, and, in some cases, further-decomposed ions from the amine-component ions. A new analytical system was established on the basis of the analysis of the mass fragmentations of 27 samples, and applied to three unknown samples. The structure of these pigments can be deduced from the low-resolution mass spectra for those derived from substituted anilines, and from the high-resolution spectra for those derived from other amines.