bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparations and Reactions of N-Benzoyl- and N-Ethoxycarbonylcarbodiimides
Authors: Mitsunobu Oyo , Tomari Masazumi , Morimoto Hiroo , Sato Toshio , Sudo Michio 
Published: July 2006

Abstract
The reaction of N-benzoyl-N-t-butylthiourea with either diethyl azodicarboxylate or azodibenzoyl resulted in the formation of benzoyl-t-butylcarbodiimide in 84% and 48% yields, respectively. Dehydrosulfurization of various thioureas was also effected with mercuribenzamide. Benzoyl- or ethoxycarbonylcarbodiimides were obtained in over 80% yields. The reaction of benzoyl-t-butylcarbodiimide with one equivalent each of N-benzoylglycine and glycine ethyl ester led to the formation of N1-benzoyl-N2-t-butyl-N3-(ethoxycarbonyl)methylguanidine in a good yield, no N-benzoylglycylglycine ethyl ester being isolated. When benzoyW-butylcarbodiimide was allowed to react with benzoic acid, dibenzimide and t-butyl isocyanate were formed. Similarly, N-ethoxycarbonylbenzamide and N-benzoylglycine(N′-ethoxycarbonyl)amide were prepared in good yields.
The Structural Elucidation of Sesquiterpene Lactones from Petasites japonicus Maxim
Authors: Naya Keizo , Hayashi Mitsuo , Takagi Ichiro , Nakamura Seisuke , Kobayashi Masakazu 
Published: July 2006

Abstract
The structures and absolute configurations of five new sesquiterpenic lactones—fukinolide (1), dihydrofukinolide (2), homofukinolide (3), S-fukinolide (4), and fukinanolide (5)—isolated from the flower stalks of Petasites japonicus Maxim. have been established by a combination of spectroscopic and chemical methods, and by correlation with the known fukinone (25).
The X-Ray Emission Spectra of the Compounds of Third-period Elements. II. The K Spectra of Phosphorus in Compounds
Authors: Takahashi Yoshihito 
Published: July 2006

Abstract
On sixteen compounds of phosphorus, the wavelength shifts of the Kα1,2 lines and the fine structures of the Kβ band of the phosphorus emission spectra were measured. For the oxygen compounds, the relationship between the intensity ratio of the Kβ′ line and the energy shift of the Kα1,2 lines was found to be expressed by a straight line similar to that found for sulfur and chlorine compounds. In the spectra of the oxyacids and their salts, the intensity ratio of the satellite line which is observed between the Kβ1 and Kβ′ lines is proportional to the number of the hydroxyl groups in a molecule. The appearance of this line seems to be attributable to the covalent bond between a third-period atom and a non-ionized atom. In the Kβ spectrum of triphenyl phosphite, the strong satellite line at the highest energy site seems to have a nature similar to those found in sulfite, chlorate, and phosphorus trichloride.
Spin Relaxation Effects on the ESR Spectrum of Gaseous Oxygen Atoms
Authors: Jinguji Mamoru , Mori Yuji , Tanaka Ikuzo 
Published: July 2006

Abstract
The linewidths of the single-quantum transitions of O(3P1) and O(3P2) in gaseous diluents, such as oxygen molecules and an inter gas, are measured with an ESR spectrometer of a usual type. The cross sections calculated from the pressure broadening are given. With regard to the multiple-quantum transitions in the Zeeman sub-levels of O(3P2) the dependence of the linewidths on the pressure is duscussed. The spin-lattice relaxation time, T1 for the single-quantum transitions of O(3P2) or O(3P2) is evaluated by employing the standard power saturation technique, and the effectiveness of an inert gas on T1 is studied. The spin-lattice relaxation between the Zeeman sublevels of the O atom is caused by the coupling between the orbital momentum and the electron-spin state upon collision. With regard to the multiple-quantum, the relaxation mechanism is also studied. Finally, we study the relationship between the spin-lattice relaxation time, T1, and the corresponding probabilities of ΔMJ=±1, ΔMJ=±2, ΔMJ=±3, and ΔMJ=±4 transition induced by collisions.
The Polymorphism and Physical Properties of the 1,6-Diaminopyrene-p-chloranil and Related Molecular Complexes
Authors: Koizumi Shigeo , Matsunaga Yoshio 
Published: July 2006

Abstract
The 1,6-diaminopyrene-p-chloranil complex is dark blue when crystallized from chloroform and brown when crystallized from benzene. These two substances are distinctly different in X-ray diffraction, electronic spectrum, vibrational spectrum, and also electrical resistivity. The brown form, the resistivity of which is about 105 ohm cm, can be transformed into a third form, exhibiting only a few ohm cm, by compression in the presence of benzene or some other aromatic solvents. Dimorphic forms are also found with the complexes of trichloromonobromo-and dichlorodibromo-p-benzoquinones. One of these forms is of a similar nature to the dark blue-colored p-chloranil complex. The other form is brown. Only the brown form is obtainable for the complexes of mono-chlorotribromo-p-benzoquinone and p-bromanil. All the brown complexes except that of p-chloranil are similar and exhibit resistivities of the order of 103 ohm cm. In addition, black products exhibiting resistivities of several ohm cm can be prepared by using acetone as the solvent with 1,6-diaminopyrene and tetrahalo-p-benzoquinones. Contrary to the afore-mentioned complexes, no definite composition can be assigned to these low-resistivity products.
Re-absorption Effect of Charge-Transfer Fluorescence by the Excited Electron Donor-Acceptor Complex
Authors: Masuhara Hiroshi , Mataga Noboru 
Published: July 2006

Abstract
It has been shown that excited electron donor-acceptor (EDA) complexes of s-tetracyanobenzene (TCNB) with benzene or toluene can be produced quite densely when excited with a giant pulse laser and that there arises a remarkable re-absorption of the charge-transfer (CT) fluorescence by the excited EDA complexes. We have investigated in detail the re-absorption effect by examining the dependence of the CT fluorescence spectra on the direction of observation, the decay function of the fluorescence, the effect of the concentration of solution as well as the effect of the exciting light intensity on it. The excited singlet-singlet (Sn←S1) absorption spectra have been obtained by analyzing the re-absorption effect. Since the CT fluorescence spectra are broad and have no structure, the fluorescence can work as a good light source for the absorption spectral measurement.
Polarographic Investigation of Alkali Metal Ions in Hexamethylphosphoramide
Authors: Izutsu Kosuke , Sakura Sachiko , Fujinaga Taitiro 
Published: July 2006

Abstract
The polarographic behavior of alkali metal ions in hexamethylphosphoramide (HMPA) has been found to be greatly influenced by the cations of the supporting electrolytes. With 0.05 m Et4NClO4 as the supporting electrolyte, cesium and rubidium ions give diffusion-controlled, reversible waves at−2.32 and −2.35 V, respectively, vs. the Ag/0.1 m AgClO4 electrode, but sodium and lithium ions are not reduced until the reduction of the supporting electrolyte (−3.1 V). The potassium ion gives a wave at −2.37 V with a limiting current controlled by the rate of the preceding process. In 0.05 m Bu4NClO4 solutions, the reduction wave of the potassium ion is diffusion-controlled, but that of the sodium ion is kinetic and is very small. The lithium ion is not reduced until −3.1 V. In 0.05 m LiClO4, even the sodium ion is reduced reversibly with E1⁄2 at −2.47 V, while the reduction of the lithium ion starts from −2.65 V. In mixed supporting electrolytes, the presence of the tetraethylammonium ion is the determining factor of the electrode processes. From the measurements of the electrocapillary curves and of the conductivities, the effect has been attributed to the change in the double-layer properties with the cations of the supporting electrolytes.
Electronic Spectra and Electronic Structure of Iron(II) Tetraphenylporphins
Authors: Kobayashi Hiroshi , Yanagawa Yasuo 
Published: July 2006

Abstract
Tetraphenylporphiniron(II) was synthesized and isolated in a pure state. The iron(II) porphin was in the state of S=2. The spin state of iron(II) porphin varies with the axial ligand field. Oxygeneous axial ligands such as tetrahydrofuran and dioxane gave an intermediate spin state (S=1), while nitrogeneous ligands such as pyridine gave a diamagnetic state (S=0). The electronic spectra of tetraphenylporphin complexes of iron(II) were measured for the three types of the spin state.
Magnetic Moments and Electronic Spectra of Low-spin Cobalt(II) Complexes
Authors: Nishida Yuzo , Kida Sigeo 
Published: July 2006

Abstract
Comprehensive elucidation of optical and magnetic properties of low-spin cobalt(II) complexes of various types has been attempted. The g-values and magnetic susceptibilities of the complexes have been calculated, the necessary numerical data being obtained from the spectral data and reasonable assumptions. Fairly good agreement has been obtained between the calculated and experimental values.
Reactions of Alkylidenetriphenylphosphoranes with Sulfur
Authors: Tokunaga Hirokazu , Akiba Kin-ya , Inamoto Naoki 
Published: July 2006

Abstract
Reaction of diarylmethylenetriphenylphosphoranes with sulfur gave thiobenzophenones and triphenylphosphine sulfide in good yields. Reaction of benzylidenetriphenylphosphoranes with sulfur gave triphenylphosphine sulfide and 5,7-diphenyl-l,2,3,4,6-pentathiepane. More active alkylidenetriphenylphosphoranes such as isopropylidene- or sec-butylidenetriphenylphosphorane gave the corresponding phosphonium betaine containing sulfur atoms or phosphonium salt produced through air oxidation and hydrolysis of the betaine. α-Benzoylbenzylidenetriphenylphosphorane did not react with sulfur. Reactivity of alkylidenephosphoranes toward sulfur was briefly discussed.
The Synthesis of the New 1,4,2-Dithiazine Ring
Authors: Hasegawa Kiyoshi , Hirooka Syuzi 
Published: July 2006

Abstract
Some derivatives of N-(2-phenylethene-l-sulfonyl)-N′-alkylthioureas of the R1C6H4CH=CHSO2NHCSNHR2 2 type were synthesized by a reaction between 2-phenylethene-l-sulfonamides 1 and isothiocyanates in acetone in the presence of K2CO3. A new heterocyclic system, 3-alkylamino-5-phenyl-1,1-dioxo-5,6-dihydro-l,4,2-dithiazine 3, was obtained by the intramolecular Michael cycloaddition of 2 in weakly basic media, and also by the thermal cyclization of 2. The carbon-sulfur bond in 3 could be cleaved to give 2 again in strongly basic media.
The Reduction of Chlorodeoxy Sugars by Tributyltin Hydride
Authors: Arita Hitoshi , Ueda Nobuhiko , Matsushima Yoshio 
Published: July 2006

Abstract
Acetylated chlorodeoxy sugars were prepared by the use of sulfuryl chloride. These chlorodeoxy sugars were then successfully reduced to deoxy sugars by the use of tri-n-butyltin hydride. α,α-Azobis-isobutyronitrile, which has been known to be an effective radical initiator, was found to be indispensable for the reaction.
The Synthesis of 2,3-Dimethyl-3-(5-bromo-2-methoxy-4-methylphenyl)-cyclohexene, a Potentially Useful Intermediate for the Syntheses of Aplysin and Related Sesquiterpenes
Authors: Yamada Kiyoyuki , Yazawa Hisatoyo , Hirata Yoshimasa 
Published: July 2006

Abstract
As a key intermediate for the syntheses of aplysin, 1, a bromine-containing sesquiterpene isolated from Aplysia kurodai, and related sesquiterpenes, 2,3-dimethyl-3-(5′-bromo-2′-methoxy-4′-methylphenyl)cyclohexene, 2, was synthesized, starting from an anisole derivative, 6. The reactivity of the double bond in 2 towards oxidizing reagents was examined: the cyclohexene, 2, reacted with ozone to give an epoxide, 12, and a cyclohexanone, 13; an isomerization product of 12; 2 could be converted to the diol, 15, with osmium tetroxide in the presence of pyridine.
Photoemission of Ion Radical Salts. Benzonitrile- and Triphenylene-Alkali Metal Complexes
Authors: Kawamura Haruki , Inokuchi Hiroo 
Published: July 2006

Abstract
The photoelectric emission of the benzonitrile-alkali metal salts were measured and compared with those of the hydrogen-chemisorbed samples. The adsorption of hydrogen onto the salt caused a decrease in the quantum yield of the photoemission at a higher energy region and also a decrease in the threshold energy. The threshold energies were 5.05± 0.02 eV for the benzonitrile-rubidium ion radical salt and 4.95± 0.02 eV for its hydrogenchemisorbed sample. Further, the spectral response of the quantum yield of the photoemission for the triphenylenecesium complex was measured. The threshold energies of the mono- and dinegative ions were 2.40 eV and 2.43 eV respectively, and the quantum yield of the mononegative salt was ten times than that of the dinegative one.
The Microwave Spectrum of trans-Ethylmethylsilane
Authors: Hayashi Michiro , Matsumura Chi 
Published: July 2006

Abstract
The microwave spectra of CH3CH2SiH2CH3 and CH3CH2SiD2CH3 in the trans form were studied. The rotational constants calculated from the spectra can be explained satisfactorily with a model which has structural parameters transferred with only a slight modification, from the values reported for dimethylsilane and ethylsilane. From the observed splittings of the spectra, the barrier to the internal rotation of the SiCH3 group was calculated to be 1520 ± 30 cal/mol, assuming that the coupling effect of the torsional motions of the other groups can be ignored. From the Stark shifts, the dipole moment was determined to be μa=0.036±0.030, μb=0.757±0.003, and μtotal=0.758±0.005 D, making an angle of 2°44′ with the b axis for the parent species, while it was determined to be μa=0.024±0.030, μb=0.758±0.003, and μtotal=0.758±0.005 D, making an angle of 1°49′ with the b axis for the deuterated species. From these results, the orientation of the dipole moment in the molecule was concluded to be along the direction slightly inclined from the bisector of the CSiC angle toward the ethyl group in the molecule.
The Diffuse Reflection Spectra of Bentonites Colored with Various Aromatic Compounds and Related Ion-radical Salts
Authors: Matsunaga Yoshio 
Published: July 2006

Abstract
Bentonites colored with each of the following aromatic compounds were examined by the method of diffuse reflection in the range from 4 to 30 kK: benzidine, 4,4′-dihydroxybiphenyl, 4,4′-dimethoxybiphenyl, perylene, tetrathiotetracene, and phenothiazine. By comparison with the spectra of the related ion-radical salts, the oxidation of the aromatic compounds to the mono- and/or di-valent cations could be proven in all of them. Except in the case of phenothiazine, the species in the colored clays was found to be drastically modified by moisture. In addition, the spectra of the copper-arene complexes recently reported by Mortland et al. were measured. The oxidation of perylene, tetrathiotetracene, and phenothiazine was found to proceed to a greater extent in the copperexchanged clays.
The Characterization of the Electronic Spectra of Heterocyclic Amine N-Oxides by Means of the Non-Aqueous Oxidation and Reduction Potentials and the Substituent Effects on Them
Authors: Miyazaki Hiroshi , Kubota Tanekazu , Yamakawa Masumi 
Published: July 2006

Abstract
The half-wave potentials of the voltammetric oxidation and the reduction of various heterocyclic amine N-oxides have been measured in CH3CN by the technique of a rotating platinum electrode. The reversibility of the electrode process was particularly examined for the oxidation reaction by analyzing the oxidation wave and by recording the ESR spectra. Then, the mutual relationship between the electronic spectra of these N-oxides and the values of the oxidation-reduction potentials was discussed in detail; we found that this kind of treatment is very useful in assigning the spectra. Finally, a good linear relation between the oxidation potentials of substituted pyridine N-oxides and the Hammett σ+ (Brown-Okamoto) constants was demonstrated and discussed.
Dipole Moment and Force Constants of NSCl from Microwave Spectrum
Authors: Mizumoto Setsuko , Izumi Jun , Beppu Tatsuro , Hirota Eizi 
Published: July 2006

Abstract
Dipole moment of 15N32S35Cl has been determined to be μa=0.5645±0.0085, μb=1.74±0.035, μtotal=1.836±0.036D by analyzing the Stark effect of the 11,1←00,0 transition.
Twenty-eight rotational transitions of 14N32S35Cl in the ground state have been analyzed to determine four centrifugal distortion constants: τaaaa=−6.99±0.30, τbbbb=−0.0110±0.0013, τaabb=0.176±0.014, and τabab=−0.0334±0.0068 MHz. These constants are combined with the vibrational frequencies and inertia defects to recalculate force constants: F11=10.032 md/Å, F22=1.444 md/Å, F33=0.749 mdÅ, and F23=−0.086 md.
Spectra of Anions in Pure Iodine Melt and Iodine Solution Containing Tellurium
Authors: Ichikawa Kazuhiko , Shimoji Mitsuo 
Published: July 2006

Abstract
The absorption spectra in the ultraviolet and visible region were measured as a function of the temperature for pure molten I2 and for I2+Te solutions. The two peaks found at about 305 and 370 mμ can be attributed to the I3− ion. These peaks increase with the addition of Te indicating an increase in the concentration of the I3− ion. This result is consistent with the previous interpretation of the conductivity of molten I2 containing Te. The ionization potential of I3− can be estimated to be about 3.1 eV on the basis of a cyclic analysis using the model of Stein and Treinin which was developed for anion spectra in aqueous solutions. The temperature shift of the absorption energy can also be interpreted in terms of the same model. The heat change for the I2(g)+I(g)=I3(g) reaction is estimated as −48.0 kcal·mol−1.
Reactions Leading to 1,2-Dibenzoylethanes: The Dehalogenation of Phenacyl Bromide and the Photolysis of Methyl Phenacyl Sulfoxide
Authors: Nozaki Hitosi , Shirafuji Tamio , Kuno Kiyosi , Yamamoto Yasusi 
Published: July 2006

Abstract
The dehalogenation of phenacyl bromide by means of lower-oxidation-state metallic ions complexed by DMSO gives 1,2-dibenzoylethane. The by-products are 2,4-diphenylfuran and phenacyl chloride in the presence of Cu(I) chloride, whereas acetophenone and ω-acetoxyacetophenone are produced in the reaction with Cr(II) acetate. Treatment with K3Co(CN)5/DMSO gives 1,2-dibenzoylethane and acetophenone. The second title reaction consists of the photolysis of methyl phenacyl sulfoxides, the isolated by-products being acetophenones and methyl methanethiolsulfonate. The product distribution is strongly affected by the pH of the reaction mixture and also by the benzene-ring substituents.
Molecular Orbital Treatment of Para Orientation in the Diels-Alder Reactions of 2-Substituted Butadienes with Methyl Acrylate
Authors: Inukai Takashi , Sato Hideo , Kojima Takeshi 
Published: July 2006

Abstract
The intermolecular orbital method was applied to the orientation phenomena in the Diels-Alder reactions of 2-R-butadienes (R=Me, Ph, Cl, and CN) with methyl acrylate assuming the parallel biplanar transition state geometries. Although qualitatively correct predictions of para orientation (major isomer) were obtained with the calculated overlap energies, it is suggested that the non-bonding interactions are overestimated. The simple perturbational molecular orbital method, which takes only the interactions at the terminal positions into account, was also unsatisfactory. However, frontier orbital interactions provided qualitatively correct prediction of the major isomeric product in every case.
Far Infrared Spectra and Internal-Rotation Potential of Ethyl Methyl Ether
Authors: Kitagawa Teizo , Ohno Keiichi , Sugeta Hiromu , Miyazawa Tatsuo 
Published: July 2006

Abstract
Far infrared spectra (700∼40 cm−1) of ethyl methyl ether and deuterated species (CH3CH2OCD3, CD3CH2OCH3, CH3CD2OCH3, and CD3CD2OCH3) were measured in the crystalline, liquid and gaseous states and carbon tetrachloride solution. A low temperature cell was constructed for measuring far infrared absorption of highly volatile samples in the liquid and crystalline states. Far infrared bands due to skeletal bending vibrations of the trans and gauche isomers and lattice vibrations were assigned. From analyses of isotope effects on infrared frequencies, internal-rotation vibrations of the CH3-CH2, CH2-O, and O-CH3 bonds of the trans isomer of ethyl methyl ether were found at 248, 115, and 202 cm−1, respectively, in the gaseous state. Normal vibrations were treated with the local-symmetry force field and force constants were adjusted by the method of least squares. By the use of Mathieu equation, the threefold potential barriers of the methyl groups of the trans isomer were estimated as V3(CH3-C)=3.3±0.1 and V3(O-CH3)=2.5±0.1 kcal/mol.
Exact Classical-Mechanical Calculation of the Translational-Vibrational Energy Transfer of Energized Anharmonic Diatomic Molecules
Authors: Kajimoto Okitsugu , Fueno Takayuki 
Published: July 2006

Abstract
The exact classical-mechanical calculation of the translational-vibrational energy transfer of diatomic molecules was extended to collisions between inert gas and anharmonic oscillator of varying initial vibrational energy. The systems investigated were H2–He, N2–Ar, and I2–Ar. It was found that, at lower vibrational levels, the transitions in both upward and downward directions become more efficient with an increase in the initial vibrational energy of molecules. In a high vibrational energy region, however, vibrational deactivation reaches a maximum and then diminishes as the initial vibrational energy approaches the dissociation threshold. The results illuminate the essence of a “bottleneck” to vibrational energy flow involved in the activation process of bimolecular dissociation of diatomic molecules.
The Crystal and Molecular Structure of 5-Chloro-7-iodo-8-quinolinol, Chinoform
Authors: Kashino Setsuo , Haisa Masao 
Published: July 2006

Abstract
Isomorphous crystals of 5-chloro-7-iodo- and 5,7-dibromo-8-quinolinols have been examined by X-ray analysis. Both compounds crystallize in the monoclinic space group P2⁄a with four formula units in the unit cell. The cell dimensions are: a=16.98; b=4.16; c=14.84 Å, and β=112.0° for 5-chloro-7-iodo-8-quinolinol, and a=16.34, b=4.02, c=15.52 Å, and β=115.6° for 5,7-dibromo-8-quinolinol. The structure of the former, chinoform, has been determined by the Patterson methods from data collected with MoKα radiation on Weissenberg photographs, and refined by the block-diagonal least-squares method, with anisotropic temperature factors. The final R value is 0.081 for 836 observed reflections. The quinolinol molecule is nearly planar. In the crystals, the molecules related by two-fold axis are held together by hydrogen bonds to form bent dimers, which are stacked closely by van der Waals forces along the b axis.
Structure of Ethylene Oxide Oligomer Complexes. I. A 1:1 Complex of Tetraethylene Glycol Dimethyl Ether with Mercuric Chloride
Authors: Iwamoto Reikichi 
Published: July 2006

Abstract
Molecular and crystal structure of a 1 : 1 molecular complex of tetraethylene glycol dimethyl ether CH3O-(CH2CH2O)4CH3 (TGM) with mercuric chloride has been determined by means of X-ray diffraction. The complex has a monoclinic unit cell with a=14.29, b=15.10, c=7.84 Å, and β=97.0°. The space group is P21/n. Four molecules of both TGM and mercuric chloride are contained in the unit cell. The structure was determined by the ordinary heavy atom method. The molecular conformation of TGM in the complex is approximately
CH3–O\undersetT–CH2\undersetG–CH2\undersetT–O\undersetT–CH2\underset\barG–CH2\undersetT–O\undersetT–CH2\undersetG–CH2\undersetT–O\undersetT–CH2\underset\barG–CH2\undersetT–O\undersetT–CH2\undersetG–CH2\undersetT–O–CH3,
where T, G, and \barG indicate trans, gauche, and minus gauche forms, respectively. All the CH2–O bonds are trans, while the CH2–CH2 bonds are gauche and minus gauche in the adjacent chemical units. The conforma-tional unit of
O\undersetT–CH2\undersetG–CH2\undersetT–O\undersetT–CH2\underset\barG–CH2\undersetT–
was found to be very important and favorable for coordination between the O and Hg atoms. The molecule is circular but not closed, and the five oxygen atoms, which are nearly coplanar and located at the inner side of the circular molecule, enclose one HgCl2 molecule with close interatomic distances (2.78–2.96 Å) between the O and Hg atoms.