bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystal and Molecular Structure of ω-Amino Acids, ω-Amino Sulfonic Acids and Their Derivatives. IV. The Crystal and Molecular Structure of γ-Aminobutyric Acid (GABA), a Nervous Inhibitory Transmitter
Authors: Tomita Ken-ichi , Higashi Hideko , Fujiwara Takaji 
Published: July 2006

Abstract
The structure of γ-aminobutyric acid (GABA), C4H9NO2, was determined by single-crystal X-ray diffraction analysis using the data collected on a four-circle diffractometer. The compound was crystallized from an aqueous ethanol solution as needles of the monoclinic space group P21/c with four molecules in the following unit cell; a=7.193, b=10.120, c=8.260 Å and β=111.05°. The structure was solved directly by a symbolic addition method and refined by a least-squares procedure. The final R is 9.3%. The molecular geometry is not a planar trans-zigzag configuration as found in γ-guanidinobutyric acid hydrochloride or homotaurine, but a gauche configuration with respect to Cα–Cβ bond. The expected zwitterionic structure is evident from the locations of the hydrogen atoms in a difference Fourier map, each molecule being connected with three N–H···O hydrogen bonds to form a three-dimensional network.
Studies of Enamines. III. The Reaction of 4-(1-Piperidyl)- and 4-(1-Pyrrolidinyl)-3-penten-2-ones with Aryl Isothiocyanates
Authors: Tsuge Otohiko , Inaba Akitaka 
Published: July 2006

Abstract
The reaction of enamino ketones, derived from acetylacetone and piperidine or pyrrolidine, with aryl isothiocyanates has been investigated. In contrast with phenyl isocyanates, phenyl isothiocyanates react with the enamino ketones to yield the corresponding 3-phenylthiocarbamoyl derivatives (1 : 1 adducts). The reaction with 1-naphthyl isothiocyanate forms 3-naphthylthiocarbamoyl and/or 2-thiopyridone derivatives, depending on the reaction conditions.
Molecular Structure of Ethane. Comparison of the Structure Parameters of CH3CD3 in the Torsionally Excited State and in the Ground State
Authors: Iijima Takao 
Published: July 2006

Abstract
The structure parameters of ethane have been re-examined by the use of the spectroscopic moments of inertia and the electron diffraction results, on the basis of the large amplitude theory for the torsional motion. The results have been applied to the CH3CD3-species in order to see whether or not the change of the moment of inertia in the torsionally excited state observed by Hirota and Matsumura is consistent with the theoretical prediction on the deformation of the molecular frame upon torsion proposed by Veillard. The conclusion has been affirmative. The elongation of the C–C distance by 0.0028 Å and the decrease of the HCH angle by 0.05° in the torsionally excited state as expected from the theoretical calculation have been found to be consistent with the experimental result of microwave spectroscopy.
Kinetic Studies of the Solvent Extraction of Metal Complexes. II. The Rate of the Extraction of Iron(III) with Thenoyltrifluoroacetone into Carbon Tetrachloride
Authors: Sekine Tatsuya , Yumikura Jun-ichi , Komatsu Yu 
Published: July 2006

Abstract
The rate of the solvent extraction of iron(III) in 4.0 M perchlorate ionic media with 2-thenoyltrifluoroacetone (TTA) into carbon tetrachloride has been measured under various conditions. The rate was found to be first order with respect to the concentration of iron(III) in the aqueous phase, first-order with respect to TTA in the organic phase, but independent and inversely first-order with respect to the hydrogen-ion concentration. From these results, it was concluded that the rate-determining step in this extraction is the formation of the first complex between the undissociated form, TTA(HA), and Fe3+ in the higher acid concentration range, but that the reaction between the anionic form, TTA(A−), and Fe3+ also becomes a rate-determining step as the acid concentration decreases. It was also found that chloride ions accelerate the extraction; this was interpreted by more rapid reactions between TTA (in the both forms, HA and A−) and an iron(III) chloride complex. From these results, the rate constants for the rate-determining reactions were calculated to be KHA=100.57 M−1 min−1 and KA=106.84 M−1 min−1 in 4.0 M(H, Na)ClO4 at 25 °C by means of these equations: −d[Fe3+]⁄dt=KHA[Fe3+][HA] (where [HA] is the total concentration of both enol and keto forms of uncharged TTA in the aqueous phase) and −d[Fe3+]⁄dt=KA[Fe3+]·[A−]. The FeCl2+ species reacts with both HA and A− more rapidly than does the Fe3+ species, and the rate constants of the reactions of the former are in both cases higher than those of the latter by a factor of 28.
Emission Processes in Cadmium Photosensitization
Authors: Tsunashima Shigeru , Toyono Tsutomu , Sato Shin 
Published: July 2006

Abstract
The possibility of the cadmium-photosensitized luminescence of NH3, CO2, CO, and CH4 was examined at 250 °C. In the case of NH3, a very strong band emission was observed at 432 nm, with a band width of about 100 nm. The sensitized luminescence of NH3 was attributed to the emission from an excited complex between triplet cadmium and NH3. In the case of CH4, a weak emission was observed at about 420 nm. In the cases of CO2, CO, and N2, however, no positive evidence of the sensitized luminescence was obtained. From the pressure dependence of the quenching of the 326.1 nm resonance line, the efficiencies of CO2, CO, NH3, and N2 for quenching the triplet cadmium atoms were estimated to be 0.16, 0.03, 3.3×10−4, and 4.9×10−5, respectively, the efficiencies of cis-2-butene being assumed to be unity.
Solubilization Behavior of the Surfactant–Polyethylene Glycol Complex in Relation to the Degree of Polymerization
Authors: Tokiwa Fumikatsu , Tsujii Kaoru 
Published: July 2006

Abstract
The solubilization behavior of the complexes composed of a surfactant and polyethylene glycol (PEG) toward an oil-soluble dye, Yellow OB, has been studied in relation to the degree of polymerization, n, of PEG. The solubilizing powers of the anionic surfactants, sodium dodecyl sulfate and sodium p-octylbenzene sulfonate, become greater on the addition of PEG, the extent depending on n. They increase as n increases. It is proposed that there are at least two different types of complexes, i.e., “oligomeric” and “polymeric” PEG–surfactant complexes. The boundary between the oligomeric and polymeric PEG’s is estimated to be around an n value of 10–15. With an oligomeric PEG–surfactant complex, the solubilization of Yellow OB would occur mainly in the hydrocarbon part of the surfactant micelle. With a polymeric PEG–surfactant complex, on the other hand, the solubilization would take place in the region of a complex rich in PEG. Electrical-conductivity and absorption-spectral data on the complexes are also included in this paper.
The Contact-term Contributions to Lanthanide-induced 13C Paramagnetic Shifts in Acridine, Quinoline, and Isoquinoline
Authors: Hirayama Masatoshi , Hanyu Yoshiaki 
Published: July 2006

Abstract
1H and 13C paramagnetic shifts induced by Eu(DPM)3 and Pr(DPM)3 in acridine, quinoline, and isoquinoline in CCl4 are observed. It has been found that, while the 1H shifts can be interpreted solely in terms of a pseudo-contact interaction, there is a much larger contact-term contribution to 13C shifts induced by Eu(DPM)3 than by Pr(DPM)3 in these compounds; this contribution to the 13C shifts cannot be explained by a simple combination of σ- and π-contact terms.
The Microwave Spectrum and Quadrupole Coupling Constant Tensor of Bromomethylsilane
Authors: Hayashi Michiro , Kuwada Kazunori 
Published: July 2006

Abstract
The microwave spectra of four isotopic species of bromomethylsilane have been measured, viz., the 79Br and 81Br species of BrCH2SiH3 and BrCH2SiD3. The observed rotational constants have been well explained by a model of which the structural parameters have been transferred from the corresponding parameters determined for ethylbromide and chloromethylsilane. The principal quadrupole coupling constants have been determined through the analysis of the first- and second-order effects of quadrupole coupling on the hyperfine structure of the observed spectra. It was concluded, within the experimental error, that the quadrupole coupling constants tensor of this molecule has the cylindrical symmetry around the largest principal axis, the direction of which coincides approximately with the C–Br internuclear line.
Charge Transfer Interaction between the Cation Radicals of Some Aromatic Diamines and Triethylamine
Authors: Sakata Tadayoshi , Okai Toshihiro , Sugimoto Hiroaki , Tsubomura Hiroshi 
Published: July 2006

Abstract
Electronic spectra of the cation radicals of some aromatic diamines in triethylamine were found to differ remarkably from those in other solvents such as ether or alcohol as regards (1) swelling of the absorption at around 25000 cm−1, (2) broadening of the first band system and (3) red shift of the same system. It was concluded that these phenomena are due to the charge transfer interaction between cation radicals and triethylamine.
A Study of Complex Formation by the Cation Exchange Method. Bivalent Metal Complexes with Univalent Anions
Authors: Ohyoshi Emiko 
Published: July 2006

Abstract
An attempt was made to estimate the amount of the cationic complex MA+ adsorbed on a cation exchanger. This method is based on the fact that the ratio of the distribution coefficients of M2+ and MA+ should vary with the ionic strength of the medium. The Ni(II) acetate system studied by Fronaeus has been reexamined. The results show that the distribution coefficient of NiAc+ (Ac=acetate) is negligible compared with that of Ni2+ upon the variation of the ionic strength from 0.2 to 1.0. It was found that Fronaeus overestimated the distribution coefficient of NiAc+ and that this caused the value of β2 to be much greater. In conclusion, the two functions, \varphi1 and f, introduced by Fronaeus could not be determined with high accuracy; for the stability constants obtained by Fronaeus’s method, they must be confirmed by conducting the experiment at a different ionic strength.
Photochemistry of Heterocyclic Compounds. VII. The Photochemical Behavior of Phthalazine and Quinoxaline in Acidified Alcohols
Authors: Wake Shigeo , Takayama Yuichi , Otsuji Yoshio , Imoto Eiji 
Published: July 2006

Abstract
Irradiation of phthalazine (1) and quinoxaline (2) in acidified methanol yielded 1-methylphthalazine (3a) and 2-methylquinoxaline (4), respectively. The quantum yields for the formation of 1-alkylphthalazines, which were obtained upon irradiation of 1 in acidified alcohols, varied with the sort of alcohols used and decreased in the order of methanol&gt;ethanol&gt;&gt;2-propanol. When a mixture of 1 and 2,6-di-t-butylphenol (6) was irradiated in benzene containing trifluoroacetic acid under evacuated conditions, the oxidation of 6 occurred to form 3,5,3′,5′-tetra-t-butyldiphenoquinone (7) without destruction of 1. Detailed mechanistic studies suggest that the photoalkylations of 1 and 2 in acidified alcohols proceed through an electron-transfer from solvents to an excited state of the protonated diazines.
Substituent Effects in the Benzofuran System. II. Electrophilic Bromination
Authors: Okuyama Tadashi , Kunugiza Kiyomitsu , Fueno Takayuki 
Published: July 2006

Abstract
Bromination of benzofuran (BF) and its derivatives (5-CH3, 6-CH3, 5-CH3O, and 5-Cl) has been studied kinetically in acetic acid and by product analysis under various conditions. Product analysis revealed that bromine adds to BF in trans fashion, electrophilic bromine attacking at the 2-position. Analysis of substituent effects on the rate of bromination showed that the electronic effects are transmitted through both the bond 8–3 and the bonds 9–1–2 by a comparable magnitude. The transition state of the reaction was concluded to closely resemble a cyclic bromonium ion intermediate.
Charge-transfer and Proton-transfer in the Formation of Molecular Complexes. IX. Polynitrobenzoic Acid Complexes with Aromatic Monoamines
Authors: Matsunaga Yoshio , Osawa Ryuzo 
Published: July 2006

Abstract
When 2,4,6-trinitrobenzoic acid is combined with aromatic monoamines, true benzoates are mostly formed. However, not only a white true benzoate, but also a red 2 : 1 complex of the CPT type, in which charge-transfer and proton-transfer interactions operate simultaneously between the component molecules, were obtained with aniline. In addition, the brown 2,4,5-trimethylaniline complex reported by Noelting and Sommerhoff was found to be of a similar nature. The phenomenon of complex isomerism was observed upon combination with o-chloroaniline; that is, the colorless salt isomerizes into an orange-colored charge-transfer complex at about 133 °C. Only the complexes with p-dimethylaminobenzaldehyde and o-nitroaniline, which have the lowest pKa values among the amines examined, and those with the halogenated 2-naphthylamines are of the charge-transfer type. The 3,5-dinitrobenzoic acid complexes were also examined. Complexes of the CPT type with a 3: 2 composition were isolated with aniline and p-toluidine.
The Reaction of Alcohols with Hexamethylphosphoric Triamide
Authors: Arimatsu Seiji , Yamaguchi Ryohei , Kawanisi Mituyosi 
Published: July 2006

Abstract
The thermal treatment of 4-homoadamantanol and bicyclo[3.3.1]nonanols with hexamethylphosphoric triamide (HMPT) gave the corresponding olefins in moderate yields. The application of this dehydration method to a system in which olefin formation was regarded as difficult or impossible stereochemically led to various types of reactions, i.e., reduction, substitution, and phosphorodiamidation. Upon being heated in HMPT, 2-adamantanol afforded 2-adamantyl tetramethylphosphorodiamidate, whereas 1-adamantanol was transformed into adamantane via 1-adamantyl tetramethylphosphorodiamidate. In the case of allylic or benzylic alcohols, dimethylamino-substituted compounds were obtained. The reduction of the amount of HMPT promoted the formation of an ether, while dibenzhydryl ether was produced exclusively from benzhydrol. The mechanism of these reaction is discussed.
Chemiluminescence of Succinylfluorescein and Related Compounds. I. Emitting Species Produced by the Reaction of Succinylfluorescein with Oxygen in Aprotic Solvents
Authors: Kamiya Isao , Aoki Keizo 
Published: July 2006

Abstract
In the course of our studies of the chemiluminescence of xanthene dyes, we found the violet chemiluminescence emission (CL-emission) resulting from the reaction of succinylfluorescein with oxygen in an aerated alkaline aqueous system of a high concentration of an aprotic solvent (DMSO or DMF), an especially intense emission occurring in aerated dry DMSO or DMF with tert-BuOK as base. The CL-emission comprised two emission components: an intense violet emission (a peak, at 410 nm) whose spectral distribution was similar to that of the fluorescence band which appeared during the course of the reaction, and a weak greenish-yellow emission similar to the fluorescence of the dye. By isolating and identifying the violet-fluorescent reaction product with an authentic sample, and by comparing the CL-emission with the fluorescence emission of the isolated product, it was concluded that the violet CL-emission may be attributed to the formation of an excited dianion of 3,6-dihydroxyxanthone. The reaction path leading to the dioxetane intermediate which will be produced by the elimination of a proton from the C atom at the β-position of the dye, followed by the oxygenation via the caged radical pair, was discussed as a likely mechanism for the formation of the excited dianion.
Proton Magnetic Resonance in Organic Free Radicals, BDPA–Bz and p-Cl-BDPA
Authors: Uchino Kazuhiro , Yamauchi Jun , Ohya-Nishiguchi Hiroaki , Deguchi Yasuo 
Published: July 2006

Abstract
The proton NMR absorption spectra from 1.3 to 77 K in two organic free radicals, BDPA–Bz and p-Cl-BDPA, have been measured on powder samples which undergo a magnetic phase transition from a paramagnetic to an antiferromagnetic state at the temperatures of 1.695 and 3.25 K respectively. The behavior of the NMR absorption spectra associated with the magnetic phase transition has been studied for the first time in the organic free radicals and interpreted in terms of the hyperfine interaction. These results are then compared with those of the TANOL radical, which is a linear antiferromagnet with no magnetic phase transition down to 1.3 K.
Asymmetric Reactions. IX. On the Catalytic Hydrogenation of Olefinic Compounds with Bis(dimethylglyoximato)cobalt(II)-base Complex
Authors: Takeughi Seiji , Ohgo Yoshiaki , Yoshimura Juji 
Published: July 2006

Abstract
Examination of the catalytic hydrogenation of twenty-one olefinic compounds with bis(dimethylglyoximato)cobalt(II)-pyridine complex indicates that all (Remark: Graphics omitted.) type olefinic compounds having an electron-withdrawing and a weakly electron-donating substituent are reducible. Isolation and further hydrogenation of the alkyl complexes in the case of (Remark: Graphics omitted.) type olefinic compounds, and deuterogenation of α-phenylacrylophenone support the view that α-alkyl complexes are the intermediates in hydrogenation. It is concluded that the electron-withdrawing effect accelerates both the first (alkyl complex formation) and the second (reductive-cleavage of alkyl moiety) steps, while steric compression prevents the first step and accelerates the second step. The reaction mechanism is discussed.
The Relation between the Electronic Spectra and the Oxidation and Reduction Potentials of Benzenoid Hydrocarbons
Authors: Kubota Tanekazu , Miyazaki Hiroshi , Ezumi Kiyoshi , Yamakawa Masumi 
Published: July 2006

Abstract
It was shown that the 1La band of benzenoid hydrocarbons is in a linear relation to (E1⁄2red–E1⁄2oxd) value led from the half-wave reduction and oxidation potentials. The theoretical background and the binding conditions of the application of this relation were clearly given.
The ESR Spectra of Bis(t-butyl and ethyl acetoacetato)copper(II) Complexes in Various Hydrocarbon Solvents
Authors: Yokoi Hiroshi 
Published: July 2006

Abstract
The X-band ESR spectra of bis(t-butyl acetoacetato)copper(II) and bis(ethyl acetoacetato)copper(II) in several non-coordinating solvents of hydrocarbon were measured at 77 K. Remarkable solvent effects on dimer formation were revealed for the complexes.
The Thermal Behavior of Silanol Groups of Silica Gel as Studied by Infrared Spectroscopy. I
Authors: Kondo Seiichi , Muroya Masa-aki , Fujii Kenzo 
Published: July 2006

Abstract
The thermal behavior of the silanol of silica gel has been studied by quantitative infrared spectroscopy. Transparent and glass-like plates of silica gel of high purity, after they had been heat-treated at various temperatures below 680 °C, were used for the measurement of OH stretching vibrations ranging from 3100 to 3800 cm−1. These absorption bands were analysed into the several component bands by the simulation method using a Dupont Co. Curve Resolver. The intensity of these bands in area were proportional to the OH concentrations as measured by the thermal method. Each component band disappeared at a temperature which was roughly equal to that obtained from the dielectric and conductivity measurements. From these results, assignment was attempted on the basis of these bands.
ON THE DISSOLUTION VELOCITY OF OXYGEN INTO WATER. PART I
Authors: Miyamoto Susumu , Kaya Tetsuo 
Published: July 2006

Abstract
(1) The oxidation velocity of sodium sulphite solution was observed when air is passed at various velocities.
(2) It was found that the oxidation velocities are independent of the concentration of sodium sulphite and the velocity constant was expressed as a linear function of the velocity of air passed.
(3) The dissolution velocity of oxygen into water when the concentration of oxygen in the surface layer is kept zero, was calculated from the obserbed reaction velocity, and it was found to be expressed as a linear function of the velocity of air passed.
(4) An interpretation of the mechanism of this reaction under the observed conditions was given.
(5) The maximum value of the ratio of the total number of molecules of oxygen which enter into water to the total number of molecules of oxygen which collide with the unit boundary surface per unit of time at 25°C. was calculated from the observed results.
RESEARCHES ON CHEMICAL CHANGES UNDER A STRONG ELECTRIC FIELD
Authors: Aono Takeo 
Published: July 2006

Abstract
1. A new method was devised to apply extremely strong electric force to gases and dielectric liquids, and accelerate their reactions.
2. Using this method, many reactions between gases and liquids under the action of strong electric force were studied. Thereby the effect of temperature elevation and presence of metallic powders (catalyser) were also studied.
3. In connecting with the electric discharge some interesting phenomena were observed.
ON THE DISSOLUTION VOLOCITY OF OXYGEN INTO WATER. PART II
Authors: Miyamoto Susumu , Kaya Tetsuo , Nakata Akira 
Published: July 2006

Abstract
(1) The oxidation velocity of sodium sulphite was observed when the mixture of oxygen and air was passed at uniform velocity under certain conditions.
(2) The observed oxidation velocities were independent of the concentration of sodium sulphite under the present conditions, and the velocity constant was found to be expressed as a linear function of the partial pressure of oxygen passed, as was expected.
(3) The theoretical interpretation on the observed result was given.
Metal Complexes with Amino Acid Amides. IV. Relationship between the CD Spectra of Palladium, Nickel, and Copper Complexes with cis-Bis(amino carboxamidato) metal(II) Type
Authors: Komorita Takashi , Shimura Yoichi 
Published: July 2006

Abstract
Square planar complexes of [ML] type, where M=Pd2+, Ni2+, and Cu2+ for L=N,N′-bis(l-alanyl)-1,3-propanediaminate anion and M=Ni2+ and Cu2+ for L=N,N′-bis(l-alanyl)-1,2-ethanediaminate anion, were synthesized. Their absorption and CD spectra were measured in aqueous, ethanol, and DMF solutions. The results are discussed in comparison with those of cis- and trans-bis(amino carboxamidato)complexes. Definite correspondence is found between the component d-d bands of N,N′-bis(l-alanyl)-1,3-propanediaminatopalladium(II) and those of its nickel analog, in line with a similar correspondence for the corresponding trans-bis(l-amino carboxamidato) complexes. Assignment of the component d-d bands has been reexamined for the copper complexes of bis (amino carboxamidato) type by comparing their CD data with those for the palladium and nickel analogs.
Steric Effect in 3,7-Disubstituted Tropolone. Chemical and Physical Properties of 3-Phenyl- and 3-Isopropyl-7-(2,4,6-cycloheptatrienyl)tropolones
Authors: Tezuka Takahiro , Nozoe Tetsuo 
Published: July 2006

Abstract
The preparation and chemical and spectroscopic properties of 3-phenyl-7-(2,4,6-cycloheptatrienyl)tropolone (1) and 3-isopropyl-7-(2,4,6-cycloheptatrienyl)-tropolone (2) are described. The somewhat unusual properties of 1 and 2 have been discussed in terms of the steric effect of the two substituent groups at positions 3 and 7 in the tropolone ring.
Substituent Effect in the Ionization of cis-2-Substituted 1-Cyclopropanecarboxylic Acids
Authors: Kusuyama Yoshiaki 
Published: July 2006

Abstract
Ten cis-2-substituted 1-cyclopropanecarboxylic acids (substituents: H, CH3, C6H5, CH3O, C2H5O, Cl, Br, CH3CO, CH3OCO, and C2H5OCO) were prepared, and their pKa values were determined in water at 25 °C, along with those of the trans-2-chloro and 2-methoxy derivatives. The pKa values for cis isomers are somewhat larger than those for the corresponding trans isomers, except for the chloro and bromo derivatives. The substituent effects obtained were in the usual order in the sense of the electronic effects, except for the phenyl group, which produced a decrease in acidity relative to the unsubstituted acid. It was shown that the carbon-13 chemical shifts for the methylene carbon of the ethyl group in the ethyl cis-2-substituted 1-cyclopropanecarboxylate obtained in deuteriochloroform gave a reasonable linear relation with the pKa(cis) values.