bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steady-Light Irradiation and Flash Photolysis Studies of [2.2]Metacyclophane-Iodine Systems. Mechanistic Implications of Transannular Dehydrogenation Reaction
Authors: Hayashi Shigenari , Sato Takeo 
Published: July 2006

Abstract
Irradiation of cyclohexane solutions of [2.2]metacyclophane in the presence of iodine is shown to yield 4,5,-9,10-tetrahydropyrene as the initial product. In order to clarify the mechanism of the cyclodehydrogenation reaction, steady-light irradiation, and flash photolysis experiments have been carried out. The rate of formation of 4,5,9,10-tetrahydropyrene is followed by UV spectra measurements using a characteristic band maximum at 292 nm. The rate of appearance of 4,5,9,10-tetrahydropyrene is found to be proportional to the absorption of light. The reaction is a one photon process. The reaction rate is almost constant when the concentration of iodine is less than 7×10−4 mol/l, but decreases gradually with higher concentrations. A long-lived species, whether radical or excited triplet, can not be detected by flash techniques. It is most likely that the first step involves the excited singlet. Involvement of CT-complex is proposed.
The Primary Photochemical Process of 4-Nitropyridine N-Oxide II. Decay Kinetics of the Photochemical Intermediates
Authors: Hata Norisuke , Ono Isao , Tsuchiya Tamio 
Published: July 2006

Abstract
In order to clarify the primary photochemical process of 4–nitropyridine N–oxide in solution, kinetic flash spectrophotometric studies were carried out under various conditions. The flash excitation of 4–nitropyridine N–oxide in alcoholic solution resulted in three transient species in the spectral region between 360 nm and 580 nm; one of them was a weak absorption at about 530 nm (transient species A and A′), and the other, a stronger one around 380 nm (transient species B). The experiments on the decay kinetics of these transients revealed that the photochemical reaction of 4–nitropyridine N–oxide in an alcoholic solution proceeded through these intermediate species originating from the excited singlet state; Process I (the photochemical formation of 4-hydroxypyridine N-oxide nitrate) involved the bimolecular interaction between an intermediate A′ and unexcited molecule, while Process II (the photochemical formation of 4-hydroxylaminopyridine N-oxide) was initiated by a hydrogen-atom abstraction from a solvent molecule by an intermediate B which was produced from another intermediate A. The two intermediates A and A′ were reasonably assumed to be formed concurrently from the excited singlet state of 4-nitropyridine N-oxide.
Peptides Containing Aminophosphonic Acids. II. The Synthesis of Tripeptide Analogs
Authors: Yamauchi Kiyoshi , Kinoshita Masayoshi , Imoto Minoru 
Published: July 2006

Abstract
The synthesis of tripeptides containing aminophosphonic acid was attempted as follows. Diethyl phthalylimidomethyl phosphonate (I) was chlorinated with phosphorus pentachloride to the phosphonomonochloridate (II), which was then coupled with amino acid ethyl esters to give the corresponding dipeptides (IIIa—c). The phthalyl groups of III were removed with hydrazine, and the resulting free amines were subsequently combined with phthalyl-amino acids by means of dicyclohexylcarbodiimide to produce the tripeptide analogs (IVa—c) in good yields.
Decarboxylative Alkylation in the Photolysis of Benzhydryl Esters
Authors: Fujita Shinsaku , Ozaki Yoshimi , Nozaki Hitosi 
Published: July 2006

Abstract
The photolysis of benzhydryl esters (1a—1b) results in decarboxylation, thus affording 1,1-diphenylalkanes, diphenylmethane, and 1,1,2,2-tetraphenylethane. The photochemistry of trityl and benzyl esters is also examined. The photochemical solvent incorporation proceeds in both radical and ionic senses. Most characteristically, the irradiation of 1a in toluene gives 1,1,2-triphenylethane, whereas that of 1a in methanol produces benzhydryl methyl ether. Such a dual nature of the photolysis is explained in terms of the intimate ion-radical pair hypothesis proposed by Walling.
Study of Across-Space Intramolecular Charge-Transfer Interaction by Absorption and Fluorescence Spectroscopy
Authors: Mutai Kiyoshi 
Published: July 2006

Abstract
Across-space (through-space) intramolecular charge-transfer (CT) interaction has been observed in homologous series of p-O2NC6H4(CH2)nNHAr (I) and p-O2NC6H4(CH2)nNRAr (II). Introduction of an alkyl group to the amino nitrogen of I, thus producing II, generally increases the intensity of the CT absorption band. It also induces the red-shift of the band position in most cases owing to the increase of the basicity of the donor, while the blue-shift is observed in ortho substituted derivatives. The latter effect is explained by the steric inhibition of the delocalization of nitrogen lone-pair electrons. The CT fluorescence has been observed at room temperature in the lower homologs (n=1,2, and rarely 3) of I and II. Higher intensity of the fluorescence is generally observed in n=1. The increase of intensity is observed when a small amount of benzene is added to a cyclohexane solution. The excitation spectrum shows two peaks; one at the 1Lb transition wavelength of the amine moiety and the other at the CT absorption. The former suggests the possibility that an excited donor collides intramolecularly with a ground state acceptor part (p-nitrophenyl group) to form an excited CT state, and the latter presents a strong evidence for the origin of the fluorescence being the excited CT state.
Modified Clemmensen Reductions of Keto Groups to Methylene Groups
Authors: Toda Masaaki , Hayashi Mikio , Hirata Yoshimasa , Yamamura Shosuke 
Published: July 2006

Abstract
A modified Clemmensen reduction is described for the conversion of keto-groups into methylene groups by using active zinc powder in common organic solvents and acetic anhydride saturated with hydrogen chloride; the scope and limitations of these new reduction systems are also discussed.
Mechanism of Charge-transfer Polymerization. III. Flash Photolysis of N-Vinylcarbazole–Chloranil System
Authors: Shirota Yasuhiko , Kawai Kiyoshi , Yamamoto Naoto , Tada Kazuhiro , Shida Tadamasa , Mikawa Hiroshi , Tsubomura Hiroshi 
Published: July 2006

Abstract
Photochemical formation of transient N-vinylcarbazole cation and chloranil anion-radicals has been demonstrated by means of flash spectroscopy for the N-vinylcarbazole–chloranil–solvent systems. Identification and decay of the species formed by flash illumination are described.
Infrared Spectrum and Normal Vibrations of N,N-Dimethylthioacetamide
Authors: Ray Arabinda , Sathyanarayana D N 
Published: July 2006

Abstract
Infrared spectrum of N,N-dimethylthioacetamide (DMTA) has been recorded in the region 250–4000 cm−1. Normal vibration analysis has been carried out employing Urey-Bradley force field and assignments are made and supported by comparison with related molecules. The complexes of DMTA with cobalt (II), copper (I), and mercury(II) chlorides have been prepared and their infrared spectra recorded. The frequency shifts in metal complexes are in accord with the assignments of C=S and C–N frequencies.
Photolyses of Alkyl Sulfinates and Sulfites
Authors: Kobayashi Michio , Minato Hiroshi , Miyaji Yoshiko , Yoshioka Takuji , Tanaka Koji , Honda Koichi 
Published: July 2006

Abstract
Methyl, ethyl, n-butyl, n-octyl, benzyl, and allyl p-toluenesulfinates were photolyzed in n-hexane or without solvent. The products analyses indicate that the photolyses of these esters involve the fission of ArSO–OR bond, producing a sulfinyl radical and an alkoxy radical. In the case of the allyl ester, isomerization to the corresponding sulfone took place to some extent. When optically active l-menthyl l-p toluenesulfinate was irradiated, its optical activity decreased fairly quickly while very little photolysis was observed. This photo-racemization was ascribed to the reversible formation of sulfinyl radical and menthyloxy radical. When di-n-butyl sulfite was photolyzed, the products found were explained by assuming the initial formation of n-butoxysulfinyl radical and n-butoxy radical. When n-butyl chlorosulfite was photolyzed, the products found indicate the initial fission of the S–Cl bond instead of the S–O bond.
The Structure and Synthesis of Rishitinol. A Sesquiterpene Alcohol from Diseased Potato Tubers
Authors: Katsui Nobukatsu , Matsunaga Akira , Imaizumi Kenji , Masamune Tadashi , Tomiyama Kohei 
Published: July 2006

Abstract
The structure and configuration of rishitinol (2), isolated from tuber tissues of white potatoes (Solanum tuberlosum × S. demissum) infected by an incompatible race of Phytophtora infestans, were deduced from spectral and chemical data and confirmed by the synthesis of its recemate. 5,8-Dimethyl-1-tetralone-3-carboxylic acid (13) prepared from 2,5-dimethylbenzyl chloride was esterified, reduced, and then dehydrated to the dihydronaphthalene derivative (20), which was converted into the oxyisopropyl derivative (21). The hydroboration of 21 followed by hydrogen peroxide oxidation afforded a multi-component mixture, from which dl-rishitinol (25=dl-2) was isolated along with isomeric glycols (22–24).
Constituents and Properties of Ammoniated Slurry From Wet-process Phosphoric Acid
Authors: Akiyama Takashi , Ando Jumpei 
Published: July 2006

Abstract
A large amount of gel-like substance is formed during the ammoniation of wet-process phosphoric acid and affects the production of phosphate fertilizers. The authors have found that the main constituent of the gel-like substance is a compound “S” whose composition has been determined to be (Al,Fe)NH4HF2PO4. Several other compounds, Fe3NH4H8(PO4)6·6H2O, (Fe,Al)NH4H2(PO4)2·1/2H2O, Fe(NH4)2H2F(PO4)2·xH2O, (NH4)3AlF6, gelatinous silica, etc., are also formed during the ammoniation and curing of the ammoniated slurry, depending upon pH, atomic ratio of F/(Al+Fe) and temperature. Tests also were made on the properties of the ammoniated slurry; solubility, viscosity, filterability, and the rate of sedimentation. It has been found that the properties vary with the formation of the above compounds. A high-temperature modification of (NH4)2HPO4 which is stable above 155°C has been newly found during the tests.
Vibronic Bands of Phosphorescence Spectra of Quinoxaline in Host Crystals
Authors: Ikegami Kasumi , Ito Mitsuo 
Published: July 2006

Abstract
The polarized phosphorescence spectra of quinoxaline in durene and p-dimethoxybenzene host crystals were observed at 4.2°K, and the vibronic bands of the phosphorescence spectrum were assigned. It was found that the intensity of vibronic bands polarized along long molecular axis arises from the vibronic spin-orbit coupling routes
(Remark: Graphics omitted.)
and the intensity of vibronic bands polarized along short molecular axis from the routes
(Remark: Graphics omitted.)
It was concluded that all the vibronic phosphorescence bands of quinoxaline originate from the Tz zero-field sublevel. This is in line with the results of El-Sayed and Brewer deduced from the magnetic field effect on the phosphorescence spectrum.
Absorption Band Shapes and Molecular Reorientation of Liquid Methyl Cyanide
Authors: Kakimoto Masao , Fujiyama Tsunetake 
Published: July 2006

Abstract
The shapes and intensities of the fundamental bands of liquid methyl cyanide were observed by conventional transmittance method. Using the refractive indices observed by the ATR method, the observed absorption indices were corrected for the dielectric-field effect. The band shapes were analyzed from the point of view of moment analysis or correlation-function analysis. The results indicate that the shapes of a1-type vibrations are good Lorentzian shapes, while those of the e-type can be explained as superpositions of Lorentzian and Gaussian functions. It is also found that the band-widths of the e-type vibrations were quite different from each other. Taking into account the effect of vibration-rotation interaction on the band-widths, the disagreement could be explained well. From the analyses of the band shapes of ν7 and nu8, the life-time function, ψ(t), was obtained; it represents the decay of the fraction of freely-rotating molecules.
CNDO Calculations on the Electronic Spectra of Several Saturated Compounds
Authors: Ohmichi Naoto , Tajiri Akio , Nakajima Takeshi 
Published: July 2006

Abstract
CNDO calculations of the excited states were performed on the first three members of paraffinic hydrocarbons—methane, ethane, and propane, and on three compounds of saturated three-membered rings—cyclopropane, ethylenimine, and ethylene oxide. The method gives a reasonable interpretation of the electronic spectra of both kinds of compounds.
The Isomerization of Propylene Oxide on Zeolite Catalysts
Authors: Imanaka Toshinobu , Okamoto Yasuaki , Teranishi Shiichiro 
Published: July 2006

Abstract
The selectivity and activity of propylene oxide isomerization have been investigated over zeolite catalysts at 100°C. It has been found that the acid strength of a catalyst is a dominant factor in the selectivity and activity. The stronger the acid strength, the larger the ratio of acetone to propionaldehyde. The reaction intermediates are deduced to be a propylene oxide protonated or that adsorbed on a Lewis-acid site. It has also been found that, in the cases of HY, Silnex (SiO2), and HY treated with pyridine, the selectivity and activity correlate with the strength of the interaction between the propylene oxide and the surface hydroxyl group. Moreover, it has been clarified that the H0 value of the surface hydroxyl group observed at 3660 cm−1 on HY is −8.2–−5.6, while that found at 3540 cm−1 is +4.0–+4.8.
Studies of the Sodium Salts of Homologues of Alkyl Sulfates in Aqueous Solutions in Relation to the Water Structure
Authors: Endo Harumi 
Published: July 2006

Abstract
The adiabatic compressibility (β) and the partial molar volume at an infinite dilution (\barV0) were obtained for aqueous solutions of the sodium alkylsulfates (SAS) of homologues. The sound velocity (U) and the density (ρ) were determined by the use of an ultrasonic interferometer and the float-balance method respectively. The results indicate that the slope at an infinite dilution (dβ⁄dC)0 of β vs. the concentration (C) diagram is in a linear relation with the carbon number (φ) of SAS. A similar relation was obtained between \barV0 and φ. We have derived these two relations by a statistical thermodynamical treatment based on the interstitial model of water, consisting of two species, one constituting the framework of an extended ice-1 structure with many cavities, and the other species, non-hydrogen-bonded water, occupying part of these cavities. The occupancy of the cavity with alkyl radical leads to a decrease in the structural compressibility, while the hydration of the ionic parts of the solute leads to a decrease in the compressibility due to the electrostriction. According to the calculations, the theoretical dependency of (dβ⁄dC)0 on φ is about three times larger than the experimental value. The theoretical dependency of \barV0 on φ is nearly in agreement with the experimental value, while the constant-addivite term is different.
Electrical Conduction in TCNQ Anion Radical Salts
Authors: Sakai Nobuko , Shirotani Ichimin , Minomura Shigeru 
Published: July 2006

Abstract
The temperature dependence of the electrical resistivity of single crystals of TCNQ anion radical salts with alkali metal, quinolinium, and triethylammonium cations has been investigated at temperatures between 300 and 540°K. It has been observed in these salts that the activation energy increases in the region of higher temperatures. In the cases of Na- and K(TCNQ) crystals, the reversal of the sign of the thermo-e.m.f. from the p-type to the n-type has been observed around the temperatures at which the activation energy increases. An interpretation of the experimental results is presented.
Phase Transition of Alkali Metal Cation-TCNQ Anion Radical Simple Salts
Authors: Sakai Nobuko , Shirotani Ichimin , Minomura Shigeru 
Published: July 2006

Abstract
The phase transition at 1 bar has been observed in alkali metal cation-TCNQ anion radical simple salts by means of measurements of the electrical resistivity of their single crystals. The temperature dependence of the resistivity under high hydrostatic pressures has been studied in order to investigate the effect of the pressure on this phase transition. The nature of this phase transition has been discussed. The pressure-induced new phase has also been found in these TCNQ salts at room temperature; thus, more than three phases (α, β, γ···) are considered to exist in the solid phase of these TCNQ, salts.
The Estimation of the Surface Properties of Metal Oxides by the Use of TCNQ Adsorption. II. The Electron-donor Property of Silica-Alumina, Silica-Titania, and Alumina-Titania System Surfaces
Authors: Hosaka Hiroshi , Kawashima Norimichi , Meguro Kenjiro 
Published: July 2006

Abstract
The electron-donor property of silica-alumina, silica-titania, and alumina-titania system surfaces was investigated by means of TCNQ adsorption. When TCNQ was adsorbed on the surfaces of the metal oxide systems from its acetonitrile solution, the surfaces of the metal oxides acquired the coloration characteristic of each oxide. The coloration was caused by the formation of TCNQ anion radicals on the metal oxide surfaces. The presence of the TCNQ anion radicals was confirmed by studying the ESR absorption and the electronic spectrum. The silica-alumina, silica-titania, and alumina-titania systems showed lower radical-ion-forming activity (electrondonating power) than the parent oxides-silica, alumina, and titania. The change in the activity with the composition was characteristic of each metal oxide system.
The Preparation and Some Reactions of Platinum(II) and Palladium(II) Complexes of Vinyl Ethers
Authors: Wakatsuki Yasuo , Nozakura Shun-ichi , Murahashi Shunsuke 
Published: July 2006

Abstract
Stable complexes with the general formula [Cl2ML]2 (M=Pt, Pd; L=vinyl ethers, propenyl ethers, 1,2-dimethoxyethylene) have been prepared. The IR spectra of [Cl2Pt(trans-CH3CH=CHOCH3)]2 showed a change which was attributed to the trans—cis isomerization of the coordinated olefin. A similar cis—trans isomerization was also suggested for the other propenyl ether and 1,2-dimethoxyethylene complexes. The palladium complex of vinyl t-butyl ether was found to react with aqueous NaOH in a way similar to the Wacker process.
Strain Gauge Electromicrobalance for Surface Tension Measurement
Authors: Koshinuma Masakatsu , Nakamura Akio , Seimiya Tsutomu , Sasaki Tsunetaka 
Published: July 2006

Abstract
Two types of apparatus using an unbonded strain gauge of a cantilever type for the measurement of surface tension were constructed. One is a sensitive electromicrobalance equipped with an extended arm attached to the cantilever of the strain gauge. The apparatus proved suitable as a surface balance in a completely closed system. By this apparatus, the measurement of surface tension ranging from 0 to 74 dyn/cm is possible with the accuracy of ±0.10 dyn/cm. The other type was constructed by connecting the sensing lever of strain gauge to the arm of a torsion balance with a strip of phosphor bronze. This device together with a counterbalance on the opposite side of the arm also proved to be useful as a tensiometer. Accuracy of this apparatus was a little better than that of the extended arm type balance, although a larger space is required. Both apparatus are inexpensive, easy to construct and simple to operate, and are suitable for the self-recording of time dependence of surface tension or weight change in general with sufficient accuracy. Equations proposed for the time dependence of surface tension of surfactant solution were checked by using the strain gauge tensiometer of the extended arm type.
A Consideration of Orbital Interaction in the Reaction of 1Δg Molecular Oxygen with Ethylene Derivatives
Authors: Inagaki Satoshi , Yamabe Shinichi , Fujimoto Hiroshi , Fukui Kenichi 
Published: July 2006

Abstract
The stereochemical path of the reaction between the 1Δg oxygen molecule and ethylene was examined in terms of orbital interaction. The results here obtained suggest that a path via the perepoxide intermediate or via a perepoxide-like transition state should be carefully examined in discussing not only the steric path to dioxetane, but also the mechanism of hydroperoxide formation.
Zero-point Average Structure of a Molecule Containing Two Symmetric Internal Rotors. Acetone
Authors: Iijima Takao 
Published: July 2006

Abstract
The theory of vibrational correction to the observed moments of inertia of a molecule which contains an internal rotor has been extended to the case of two symmetric internal rotors, and applied to the analysis of the structure of acetone. The zero-point average structure has been determined by using the moments of inertia obtained by microwave spectroscopy and the bond distances from gas electron diffraction. The zero-point average parameters have been determined as follows: C–C 1.517±0.003 Å; C=O 1.210±0.004 Å; C–H 1.091±0.003 Å; ∠HGH 108° 30′±30′; ∠CCC 116° O′±15′. The isotope effects in the structure parameters have also been observed in terms of the increase caused by deuteration to be δ(DCD)+10′±12′; δ(CCC)−17′±2′. The tilt angle of the methyl top was determined to be 2° 1′±30′.
Nuclear Quadrupole Resonance Study of Chloral Hydrate
Authors: Chihara Hideaki , Nakamura Nobuo 
Published: July 2006

Abstract
Three nuclear quadrupole resonance lines were observed in chloral hydrate at temperatures 20–300K, the frequencies being 38.2863±0.0004 MHz(ν1), 39.5415±0.0002(ν2), and 39.6252±0.0002(ν3) at 20.3K. Their temperature dependence was measured below 77K, showing monotonous decrease with increasing temperature. The difference in frequency between ν1 and ν2(or ν3) is probably due to a crystal field effect rather than OH···Cl hydrogen bonding as has been suggested. The spin-lattice relaxation time for all the lines, determined by pulse techniques, coincides with each other and tends to decrease rapidly above 250K. The decrease was interpreted as arising from hindered internal rotation of the CCl3 group with the activation energy of 8.8 kcal mol−1.
Photolyses of Ethoxalyl Azide in Alcohols and in Hydrocarbons Reactions of Ethoxalylnitrene
Authors: Shingaki Tadao , Inagaki Masao , Takebayashi Matsuji , Lwowski Walter 
Published: July 2006

Abstract
The photolysis of ethoxalyl azide gives ethoxalylnitrene and ethoxycarbonyl isocyanate. The nitrene adds to C=C double bonds and is inserted into O–H and C–H bonds. At high ethanol concentrations, where the singlet nitrene predominates, the O–H insertion product is formed dominantly. At low ethanol concentrations, where much of the nitrene changes to the triplet state, the hydrogen-abstraction product is preferred. The reactivity of the nitrene toward the C–H bonds of 2-methylbutane is more selective than that of ethoxycarbonylnitrene.
Sulfilimine. XVII. Syntheses and Reactions of N-Carbamoylsulfilimines
Authors: Oae Shigeru , Masuda Toshiaki , Tsujihara Kenji , Furukawa Naomichi 
Published: July 2006

Abstract
The physical and chemical properties of several new sulfilimines, N-carbamoylsulfilimines, and their syntheses were studied. The sulfilimines were prepared by the action of N-chlorourea on appropriate sulfides in acetonitrile, and their IR and NMR spectra were obtained. Thermolysis, hydrolysis and reactions with thiophenol and sodium nitrite were carried out and the results were discussed.