bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and Rotational Isomerism of Ethylenediamine as Studied by Gas Electron Diffraction
Authors: Yokozeki Akimichi , Kuchitsu Kozo 
Published: July 2006

Abstract
The structure and the rotational isomerism of ethylenediamine have been investigated by means of gas electron diffraction. Evidence has been given for the presence of one conformer (gauche) in the vapor phase (at 50–120°C); the N–C–C–N dihedral angle measured from the cis position is 64·0±4°, and the fraction of any other isomer, if present, is estimated to be less than 5%. A theoretical prediction based on the SCF-CNDO/2 method has essentially accounted for this finding. The rg distances and the angles based on the ra structure determined by a least-squares analysis on molecular intensities, with estimated limits of error, are as follows: C–C=1.545±0.008 Å, C–N=1.469±0.004 Å, ∠C–C–N=110.2±0.7°, C–H=1.109±0.01 Å, ∠C–C–H=111·9±5°, and ∠H–C–H=112·7±8°.
The Crystal Structure of 1,4-Bis(p-bromophenoxy) butane
Authors: Ishikawa Toshihiko , Karino Seiichi , Nagai Susumu , Yasuoka Noritake , Kasai Nobutami , Kakudo Masao 
Published: July 2006

Abstract
The structure of 1,4-Bis(p-bromophenoxy) butane has been determined by means of a single-crystal X-ray analysis. The compound crystallizes in the monoclinic space group Cc, with four molecules per unit cell: a=13.426, b=15.249, c=7.650 Å, and β=89.39°. The structure has been solved by the heavy-atom method. The final discrepancy index is 0.068 for 970 non-zero reflections. The conformation of the methylene chain in the –O(CH2)4O– group is gauche-trans-gauche, with internal rotation angles of 61.0, 181.0, and 55.2° respectively.
Reactions of Aliphatic Amines with p-Benzoquinone and Its Chloro Derivatives
Authors: Yamaoka Tsuguo , Nagakura Saburo 
Published: July 2006

Abstract
The reactions of various aliphatic amines with p-benzoquinone and its chloro-derivatives were studied by detecting reaction intermediates by means of the rapid scan spectrophotometric method. A detailed kinetic study on the reaction intermediate and the final product was made for the system including n-butylamine and chloranil in ethanol; the result shows that the system produces 2,5-di-n-butylamino-3,6-dichloro-p-benzoquinone via the chloranil anion and the n-butylamine cation with the rate constant of 9.8×102 sec−1mol−1l at 275.2°K. On the basis of reaction mechanisms, the reactions of various aliphatic amines with p-benzoquinone and its chloroderivatives were classified into five types. Stabilization energies due to the amino-substitution of p-benzoquinone were calculated by the composite molecule method; the result shows that the 2,5-derivative is most stable among the disubstituted p-benzoquinones.
The Phase Equilibria in the FeO-Fe2O3-V2O3 System at 1500°K
Authors: Wakihara Masataka , Katsura Takashi 
Published: July 2006

Abstract
The phase equilibria in the FeO–Fe2O3–V2O3 system have been determined at 1500°K by varying the oxygen partial pressure. The following three oxide phases have been stable in equilibrium: a sesquioxide solid solution with a corundum-type structure (approximate composition Fe2O3–V2O3), a ternary solid solution with a spinel type structure (approximate composition FeO·Fe2O3–FeO·V2O3), and a ternary wüstite solid solution with a periclase-type structure which dissolves vanadium ions up to about 10 mol per cent. The extent of the solid solution areas and the location of the oxygen isobars have been determined. The spinel phase coexisted partly with metallic iron and partly with the wüstite solid solution, corresponding to lower and higher iron contents respectively. The standard free energies of the Fe+V2O3+\frac12O2=FeV2O4 and 0.05 Fe+V2O3+Fe0.95O=FeV2O4 reactions to produce FeV2O4 have been calculated to be −45500±200 cal and −5800±400 cal respectively at 1500°K on the basis of the equilibrium oxygen partial pressure.
SN2 Reactions in Dipolar Aprotic Solvents. Chlorine Isotopic Exchange Reactions of 2-Arylethyl Chlorides, Chloromethyl Aryl Ethers, and Chloromethyl Aryl Sulfides in Acetonitrile
Authors: Hayami Jun-ichi , Tanaka Nobuo , Kurabayashi Syuji , Kotani Yasuhiro , Kaji Aritsune 
Published: July 2006

Abstract
The SN2 reactions having a symmetrical transition state were studied in a dipolar aprotic solvent. A good Hammett correlation was found for the chlorine isotopic exchange reactions in acetonitrile between tetraethylammonium chloride and three types of substituted methyl chlorides, 2-arylethyl chlorides, chloromethyl aryl ethers, and chloromethyl aryl sulfides. The reaction constant was positive for 2-arylethyl chlorides and negative for the methyl chlorides possessing an α-heteroatom. The presence of oxygen and sulfur atom on the α-position to the reaction center resulted in a rate enhancement of about 105 times and 103 times, respectively. Features of the transition states of these SN2 reactions are discussed.
Polymerization of Methyl Methacrylate by the Bis(benzoylacetonato)Copper(II)-1,10-Phenanthroline System
Authors: Kaeriyama Kyoji , Yamazaki Yukio 
Published: July 2006

Abstract
The addition of 1,10-phenanthroline accelerates the polymerization of methyl methacrylate by a β-diketonato chelate of Cu(II), Mn(II), Mn(III), Co(II), Co(III), and Fe(III), but has no effect on the chelate of Ni(II). The effect of 1,10-phenanthroline, which is composed of two pyridine units, is much greater than that of pyridine. The polymerization rate of methyl methacrylate by the bis(benzoylacetonato)Cu(II)-1,10-phenanthroline system may be represented as follows:
R p∝ [MMA]{[Cu(II)][1,10-phenanthroline]}1⁄2
The initiation reaction is assumed to be by a ligand-exchange reaction of bis(benzoylacetonato)Cu(II) with 1,10-phenanthroline, where a benzoylacetonyl ligand is displaced by 1,10-phenanthroline and Cu(II) is simultaneously reduced to Cu(I).
The Properties and Assignment of Isomers of 2,4-Dinitrophenylhydrazones of Some Aliphatic α-Keto Acids
Authors: Katsuki Hirohiko , Yoshida Tsuya , Nagai Jun , Tanaka Shozo 
Published: July 2006

Abstract
Visible and infrared spectra and some other properties of cis and trans isomers of 2,4-dinitrophenylhydrazones of some aliphatic α-keto acids have been studied. It was observed that absorption maximum of the cis isomer in visible region occurred at a longer wavelength than that of the trans isomer in ethyl acetate as well as in bicarbonate solution and vice versa in sodium hydroxide solution. In infrared region, N–H and C=O stretching bands of the cis isomer were found at longer wavelengths than the corresponding bands of the trans isomer. It was concluded that a hydrogen bond is formed between C=O and N–H groups in the cis isomer. Further evidence which supports the above conclusion was given by the difference between both isomers in the nickel complex forming reaction, sodium carbonate reaction and in the properties of sodium salt. Instability of the trans isomer appeared to increase as the number of carbon atoms in the keto acid molecule increased. 2,4-Dinitrophenylhydrazones of some other α-keto acids were found to give polymorphs but not geometrical isomers.
The N–H Stretching Absorption Band Intensities in Secondary Amides, Secondary Thioamides, and Anilides
Authors: Bai P Usha , Ramiah K Venkata 
Published: July 2006

Abstract
The intensities of the N–H stretching absorption bands of a number of N-methylamides, N-methylthioamides and anilides have been measured in a solution of carbon tetrachloride. It was observed that the intensities of the N–H stretching absorption bands of N-methylacetamide and N-methylpropionamide are considerably higher than those of the same band in the corresponding anilides. On the other hand, the intensity of the N–H stretching absorption band of N-methylformamide is of the same order as that of formanilide. The pattern of variation of the intensity of the N–H streching absorption bands in these compounds is similar to that of the C=O stretching absorption bands of the same compounds, but the variation in their frequencies is different. It was also observed that the intensities of the N–H stretching bands of N-methylthioamides are considerably higher and their frequencies are lower than those of the corresponding secondary amides.
Aromatic Arylation with Aryl Radicals. III. Gomberg Reaction in Dimethyl Sulfoxide
Authors: Kamigata Nobumasa , Kurihara Teruyoshi , Minato Hiroshi , Kobayashi Michio 
Published: July 2006

Abstract
Benzenediazonium tetrafluoroborate in dimethyl sulfoxide decomposed instantaneously with evolution of nitrogen upon addition of a dimethyl sulfoxide solution of choline or tetramethylammonium hydroxide. Orientations and partial rate factors for the phenylation of substituted benzenes indicated that the phenylating agent is not phenyl cation but phenyl radical. Hammett’s plots of partial rate factors for meta and para substitutions were good straight lines with ρm=0.34, ρp=1.63 (in choline) and ρm=0.48, ρp=1.69 (in tetramethylammonium hydroxide solutions). Decomposition of benzenediazonium tetrafluoroborate by tetramethylammonium hydroxide in aqueous solution was also studied, and the orientation and partial rate factors for the phenylation of substituted benzenes were determined.
Infrared Spectra and Normal Vibrations of N,N-Dimethylformamide and N,N-Dimethylthioformamide
Authors: Durgaprasad G , Sathyanarayana D N , Patel C C 
Published: July 2006

Abstract
The infrared spectra of N,N-dimethylformamide (DMF) and N,N-dimethylthioformamide (DMTF) have been investigated in the range 4000–250 cm−1. Assignment of the frequencies of DMF has been made on the basis of normal coordinate analysis for DMF, DMF-15N, and DMF-d7 using Urey-Bradly, modified Urey-Bradley, and symmetrized valence force fields. Calculations have been extended to N,N-dimethylthioformamide and N,N-dimethylselenoformamide, using the Urey-Bradley and symmetrized valence force fields. The assignments for DMF from the modified Urey-Bradley field are found to be more satisfactory. The frequency shifts on isotopic substitution and on complexation have been explained. The results of the calculations are discussed in comparison with other related molecules.
The Hydrogenation of Aniline over Supported Rhodium-Palladium Alloy Catalysts
Authors: Ikedate Kazue , Suzuki Sadao 
Published: July 2006

Abstract
The hydrogenation of aniline was investigated in the temperature range from 30° to 50°C over Rh-Pd alloy catalysts supported on activated carbon. The reactions were mainly carried out in acetic acid at an atmospheric pressure of hydrogen. The activity per unit weight of the catalysts was measured and plotted for the alloy composition. It showed a maximum at 75–85 wt% Rh. However, the activity per unit of surface area showed a maximum at about 25 wt% Rh, and the minimum activation energy of this reaction was observed at the same composition. The relationship between the selectivity and the alloy composition was also studied. The maximum selectivity to dicyclohexylamine was observed at 20–30% Rh, while the maximum formation of N-phenylcyclohexylamine appeared at 50–60% Rh. However, the selectivity to cyclohexylamine showed a minimum at about 25% Rh. The initial rates of the formation of cyclohexylamine and N-phenylcyclohexylamine were measured and plotted for the catalyst composition. The maximum activity was observed at about 85 wt% Rh for the formation of cyclohexylamine and at 50–60% Rh for the formation of N-phenylcyclohexylamine. Then the ratios of the two simple reaction rates were calculated. At a higher Rh content, (above about 25% Rh), the selectivity increased as the ratio increased. The reaction over the catalysts prepared by different methods and the hydrogenation of aniline in cyclohexane were also investigated.
The Electrolytic Conductances of Bis(halogenoacetato)bis(ethylenediamine)cobalt(III) Ions in Water
Authors: Yokoi Masatoki , Kuroda Kashiro 
Published: July 2006

Abstract
The electrolytic conductances of bis(halogenoacetato)bis(ethylenediamine)cobalt(III) perchlorate, [Co(halac)2(en)2]ClO4 where Hhalac=CH3CO2H, CH2ClCO2H, CHCl2CO2H, CCl3CO2H, and CF3CO2H were measured in water at 25°C. The equivalent conductances of the solutions (c=10−3–10−4 mol/l) were obtained from the conductance kinetic runs by extrapolating conductances to time zero. The ionic equivalent conductances of the complex ions were 21.5–17.2 ohm−1cm2eq.-−1. and decreased with the increase of the chlorine content in the chloroacetato ligands. Little differences in the ionic equivalent conductances were observed between a pair of cis and trans isomers. The rate constants of the first order aquation of the complexes were estimated.
Two Types of Complexes of o-Phenylenediamine with Tetracyanoquinodimethane
Authors: Ohmasa Masatake , Kinoshita Minoru , Akamatu Hideo 
Published: July 2006

Abstract
o-Phenylenediamine and tetracyano-p-quinodimethane (TCNQ) were shown to form two types of solid complexes with compositions of 1 : 1 and 2 : 1. The 2 : 1 complex is essentially of ionic type, while the 1 : 1 complex is characterized as of non-bonding type from the analysis of its infrared absorption spectrum. It was shown that the difference in type is reflected on the magnetic and electrical properties of these complexes. The ESR absorption or the spin concentration of the 1 : 1 complex changed irreversibly with grinding or heat-treatment (70°C), while no appreciable change was observed in the 2 : 1 complex with these treatments. The electrical resistivity is lower for the 1 : 1 complex than the 2 : 1 complex by a factor of 102. From these observations, it is considered that the ground state electronic structure of the 1 : 1 complex is in a similar situation to those of diaminopyrene-chloranil and benzidine-TCNQ complexes.
The Flow Properties of Hydrophilic Latexes Thickened with Alkali
Authors: Ito Yoshio , Shishido Shunsuke 
Published: July 2006

Abstract
This paper has aimed at the revelation of the thickening mechanism of a latex on the addition of alkali. Experiments have been made on two kinds of latexes dialyzed thoroughly, i.e., the butadiene–methyl methacrylate copolymer latex and the butadiene-methyl methacrylate–methacrylic acid copolymer latex. The degree of the swelling of the latex particles on the addition of alkali has been correctly obtained and has been connected with the thickenability of the latex. The results provide a more rigorous description than Wesslau’s suggestion that the thickening of a latex on the addition of alkali is ascribed to the swelling of the latex particles alone. The reason why NH4OH is a proper thickener is presented, and the most suitable amount of alkali for the thickening of a latex is discussed.
Studies on Aminosugars. XXIX. Syntheses of Nucleosides of 3-Amino-3-deoxy-3-C-hydroxymethyl-β-d-ribofuranose
Authors: Yanagisawa Hiroaki , Kinoshita Mitsuhiro , Umezawa Sumio 
Published: July 2006

Abstract
Reduction of 3-acetamido-3-C-carboxy-3-deoxy-1,2-O-isopropylidene-α-d-ribofuranose-y-lactone (1) with lithium aluminum hydride or sodium borohydride followed by acetylation gave 3-acetamido-3-C-acetoxymethyl-5-O-acetyl-3-deoxy-1,2-O-isopropylidene-α-d-ribofuranose (2). Hyrdolysis of 2 followed by N-phthaloylation and O-acetylation gave 3-C-acetoxymethyl-5-O-acetyl-3-deoxy-1,2-O-isopropylidene-3-phthalimido-α-d-ribo-furanose (7), which was acetolyzed and chlorinated to give acylglycosyl chloride (9). Condensation of 9 with 6-benzamidopurine followed by aminolysis afforded 9-(3′-amino-3′-deoxy-3′-C-hydroxymethyl-β-d-ribofuranosyl) adenine (11). 6-dimethylaminopurine, guanine, cytosine and uracil derivatives were similarly synthesized.
Studies on Hetero-Cage Compounds. II. pKa Studies on the 3,10-Diazabicyclo[4.3.1]decane System
Authors: Sasaki Tadashi , Egughi Shoji , Kiriyama Tsutomu 
Published: July 2006

Abstract
The pKa values of pseudopelletierine (1), 10-methyl-3,10-diazabicyclo[4.3.1]decan-4-one (2), 10-methyl-3, 10-diazabicyclo[4.3.1]decane (3), 6,8-exo-ethanopseudopelloetierine (4), 7,9-exo-ethano derivatives 5 and 6 of 2 and 3 were measured potentiometrically in water-methyl cellosolve (20 : 80 v/v) at 20°C. The conformational problems in the 3,10-diazabicyclo[4.3.1]decane system were discussed based on the observed pKa′ (pKmcs) values. The characteristic conformational behavior of the monocation (7) of 3 was suggested by the higher value of its pKmcs than of 6.
The Synthesis and Photo Reaction of 7,11-Dimethyl-1,6,10-dodecatrien-3-one
Authors: Kato Tadahiro , Maeda Hideo , Tsunakawa Mitsuaki , Kitahara Yoshio 
Published: July 2006

Abstract
For the purpose of constructing a pinene skeleton (I), a promising intermediate for the synthesis of bergamotenes (III), the vinyl ketone (II), was synthesized from geranyl bromide (IV) by the application of Meyer’s method, followed by a Grignard reaction with vinylmagnesium bromide and subsequent oxidation. The irradiation of II in absolute ether afforded an unexpected keto ether (X) in a low yield; it was characterized by means of a deuterium-exchange reaction and physical methods. No other product except X was isolated from the photoreaction mixture of II.
Studies on the Electronic Spectra of the Semiquinones of Anthracene and Its Related Heterocycles. II
Authors: Masuhara Hiroshi , Okuda Michio , Koizumi Masao 
Published: July 2006

Abstract
The electronic structures of semiquinones of anthracene and its related heterocycles were calculated, using the open shell SCF procedure combined with configuration interaction calculations. A general classification and some peculiarities of the observed absorption spectra of these semiquinones can be readily explained by the present theoretical results. The effects of resonance integral and configuration interactions were examined in detail. The results obtained by considering the effect of hyperconjugation were added.
The Formation of κ and κ′-Al2O3 from the Dehydration of Tohdite 5Al2O3·H2O
Authors: Okumiya Masataro , Yamaguchi Goro , Yamada Osamu , Ono Shuichiro 
Published: July 2006

Abstract
The dehydration of tohdite 5Al2O3·H2O is well followed by means of the single-crystal electron-diffraction patterns, the X-ray powder patterns, differential thermal analysis, and the measurement of the density. Thermogravimetric measurements were also performed, both under a normal atmosphere and in a high vacuum. Just after the dehydration, an unstable intermediate phase was obtained; it was denoted as κ′-Al2O3(from tohdite). The mechanism of the transformation series:
tohdite→κ′-Al2O3→κ-Al2O3→α-Al2O3
was discussed, and some basic data to serve as clues to elucidate the crystal structure of κ′- and κ-Al2O3 were obtained.
Study of Acidity Constants of 3-, 4-, 5-, and 6-Chloro-o-toluidinium Ions in Aqueous Solution and Related Thermodynamic Quantities. I
Authors: Gandhi A H , Patel S R 
Published: July 2006

Abstract
The acidity constants of anilinium, simple and 3-, 4-, 5-, and 6-chloro-o-toluidinium ions have been studied at seven different temperatures by pH metry in aqueous solution and correlated using the relation lnK=A+BT+CT2. The values of ΔG, ΔH, ΔS, and ΔCp have been calculated at different temperatures. The possibility of the additivity in the thermodynamic quantities of these disubstituted anilinium ions has been examined. Hammett type equation has been developed to correlate the acidity constant of these ions at 25°C. Attempt has been made to explain the trends in the thermodynamic quantities of these ions in terms of polar, steric, and solvent effects.
Thermal and Photolytic Decompositions of Azobis(2-phenylthio)-2-propane
Authors: Ohno Atsuyoshi , Kito Noboru , Ohnishi Yutaka 
Published: July 2006

Abstract
Thermal and photolytic decompositions of azobis(2-phenylthio)-2-propane have been studied. The reaction mechanisms have been discussed on the basis of products. Almost all reactions of 2-phenylthioprop-2-yl radicals produced from the azo compound photolytically proceed with in-cage processes. The ratio, disproportionation/dimerization, predicts qualitatively that the radical center of the free radical is more electronegative than that of the corresponding oxygen analog.
The Reaction of α-Oxo Acids with N-Phenyltriphenylphosphinimine
Authors: Shin Chung-gi , Ando Hiroki , Yoshimura Juji 
Published: July 2006

Abstract
The reaction between ethyl α-oxocarboxylate and N-phenyltriphenylphosphinimine gave a mixture of ethyl α-phenyliminocarboxylate (IVa–f) and the tautomeric isomers (Va–f) in good yield. IVa and Va derived from ethyl pyruvate was converted gradually into 3-anilino-5-ethoxycarbonyl-5-methyl-1-phenyl-Δ3-pyrrolin-2-one (VIIa) on standing at room temperature. The free acid of IVa and Va prepared by the same method could not be purified, but a small amount of 3-anilino-5-methyl-l-phenyl-Δ3-pyrrolin-2-one (IX) was obtained from the reaction mixtures. In the reaction of aniline and pyruvic acid, α,γ-dianilino-γ-carboxy-α-methyl-γ-butyrolactone (XII) was obtained in the neutral reaction condition and 4-anilino-2-phenyliminopentanoic acid (XIV) in basic condition. The structure of the products was proved by NMR and IR spectrum, and the reaction courses were discussed.
Solvent Effects on the Spin-Lattice Relaxation Times and Chemical Shifts of N-Methylacetamide and N,N-Dimethylacetamide
Authors: Sato Kazuo , Nishioka Atsuo 
Published: July 2006

Abstract
The spin-lattice relaxation time T1 and chemical shift of N-methylacetamide (NMA) and N,N-dimethylacetamide (DMA) were measured in D2O and CCl4 solutions. In D2O solution, it has been found that the weak interamide hydrogen bonding of NMA does not affect the spin-lattice relaxation entirely, and the molecular motion of NMA and DMA is almost identical. However, quite different results were obtained for CCl4 solution. The molecular association of NMA in CCl4 solution is strong enough to exhibit appreciable effects on spin-lattice relaxation. The life time of the associated molecules has been estimated to be longer than 10−10–10−11 sec. The association of DMA at high concentration region in CCl4 could be verified from the concentration dependence of the spin-lattice relaxation rate as well as chemical shift.
Reaction of Aromatics with Thallic Salts—Preparation of Arylthallic Compounds
Authors: Ichikawa Katsuhiko , Uemura Sakae , Nakano Takeshi , Uegaki Eizo 
Published: July 2006

Abstract
Arylthallic acetate perchlorate monohydrates, Ar-Tl(OAc)(ClO4)·H2O, were obtained as the major products of the reaction between thallic acetate and aromatics in acetic acid containing perchloric acid. As the minor products, various types of oxidation products including oxidative coupling were obtained. Reactivity order of the aromatics and the isomer distributions in the products were the same as those in the usual electrophilic aromatic substitution. With thallic nitrate, sulfate, and chloride, no arylthallic compounds could be obtained.
Studies on Cobaloxime Compounds. I. Synthesis of Various Cobaloximes and Investigation on Their Infrared and Far-Infrared Spectra
Authors: Yamazaki Noboru , Hohokabe Yorikatsu 
Published: July 2006

Abstract
Cobaloximes with the general formula: [CoX(DH)2B] or [RCo(DH)2B] (X: Cl, CN. R: Alkyl groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, benzyl, or hydroxypropyl. DH: Dimethylglyoximato monoanion. B: Bases such as water, nicotinamide, p-toluidine, pyridine, γ-picoline, imidazole, or 4-vinylpyridine), and polymeric cobaloximes with the general formula: [Co(OH)(DH)2(Copoly–AM-VPy)] (Copoly–AM-VPy: a low molecular weight copolymer of acrylamide and 4-vinylpyridine), were synthesized and their infrared and far-infrared spectra were examined. The frequency shifts by changing the axial ligands were discussed.