bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Formation of Trapped Electrons upon the Thermal Dehydrationcondensation of Hydrated Hydrogenorthophosphates
Authors: Kawazoe Hiroshi , Nishino Masaru , Hosono Hideo , Isozaki Kei , Ametani Kazuo , Imai Masahiko , Kanazawa Takafumi 
Published: July 2006

Abstract
Radical formation was found in the thermal dehydration-condensation process of hydrated hydrogenorthophosphates (HHP). It was considered that the intermediate radical reacted with lattice defects, thus resulting in the generation of trapped electrons. The gray coloration and the ESR sensitivity of the heated HHP were assigned to the formation of the trapped electron.
Extraction of Lanthanoids from Hydrochloric and Nitric Acid Solutions by Di(2-ethylhexyl)phosphoric Acid
Authors: Hirashima Yoshiyuki , Yamamoto Yasuhiro , Takagi Shigeru , Amano Taisuke , Shiokawa Jiro 
Published: July 2006

Abstract
Di(2-ethylhexyl) phosphoric acid+ (D2EHPA or HX) extracts lanthanoids (Ln) from a moderately acidic solution by cation exchange reaction: Ln3++m(HX)n\ightleftarrowsLnX3·3HX+3H+. From the mode of extraction m is estimated to be 3 in benzene diluent, and smaller than 3 in heptane diluent. The change of the relative extractability with the atomic number of lanthanoids is in line with what is expected from the concept of the tetrad effect proposed by Peppard et al. When the hydrogen ion concentration is very high, the main reaction is solvation: Ln3++3A−+q(HX)n\ightleftarrowsLnA3·4HX. In benzene diluent q is 2 and n is 2, while q is 1.6–1.7 in heptane diluent. It can be attributed to the difference in the association degree of D2EHPA that m or q is smaller in heptane than in benzene.
Induced Circular Dichroism Spectra of Some Achiral and Racemic Cobalt(III)–Amine Complexes in Aqueous (R,R)-Tartrate and (R,R)-Tartratoantimonate(III) Solutions
Authors: Miyoshi Katsuhiko , Oh Chang Eon , Nakazawa Hiroshi , Yoneda Hayami 
Published: July 2006

Abstract
The induced circular dichroism (ICD) spectra were measured in the first d-d transition region for the following cobalt(III)–amine complexes in aqueous solutions of (R,R)-tartrate and (R,R)-tartratoantimonate(III) anions; [Co(en)n(NH3)6−2n]3+ (n=0–3) and cis-[Co(en)2(RNH2)2]3+ (R=methyl and ethyl). It was found that a single negative CD band was induced for all the complexes in (R,R)-tartrate solution, while a single positive one was induced for most of them in (R,R)-tartratoantimonate(III) solution; the ICD developed in it was composed of a single negative band for [Co(en)3]3+ and of two bands with opposite sign for trans-[Co(en)2(NH3)2]3+ and cis-[Co(en)2(EtNH2)2]3+. The ICD spectra obtained for racemic complexes were interpreted in terms of differential interactions of Λ- and Δ-enantiomers with (R,R)-tartrate or (R,R)-tartratoantimonate(III), and an attempt was made to correlate the sign of their ICD spectra with their chromatographic behavior on an SP-Sephadex ion-exchanger with these chiral anions as an eluent.
The Linearity of the Substituent-induced Carbon-13 Chemical Shifts of α-Carbons with Charge Densities in Aromatic Side Chains. Semi-empirical Calculations for 4-Substituted Derivatives of Styrenes, α-Methylstyrenes, and Biphenyls
Authors: Niwa Jun 
Published: July 2006

Abstract
The contributions to 13C shifts from the diamagnetic term of the neighboring carbon atom and from the “ring-current” have been estimated by means of the equations given in a previous paper (J. Niwa, Bull. Chem. Soc. Jpn., 48, 118 (1975)). A semi-empirical expression has been derived for the substituent-induced 13C chemical shift in an aromatic side chain by considering such contributions in addition to the local diamagnetic and paramagnetic terms of the carbon atom in question. The applicability of the expression has been examined for α-carbons of 4-substituted derivatives of styrenes and α-methylstyrenes, and for 1′-carbons of 4-substituted biphenyls.
Studies of the Isomerization of Unsaturated Carboxylic Acids. IV. Base-catalyzed Rearrangements of β,γ-Unsaturated Esters to α,β-Isomers
Authors: Sakai Mutsuji , Nishikawa Sh\={u}ji , Koike Haruo , Sakakibara Yasumasa , Uchino Norito 
Published: July 2006

Abstract
Dimethyl methylenesuccinate, dimethyl citraconate, and dimethyl mesaconate mutually rearranged in the presence of triethylamine at room temperature. The rearrangement was found dependent on the polarity of the solvent and the basicity of the amine, and the rate was found to be first-order in both ester and amine. A mechanism has been proposed from a kinetic study.
An 1H and 13C NMR Spectroscopic Study of Ethyl 3-(2-PyrimidyI-amino)crotonate, Ethyl 3-(5-Bromo-3-pyridylamino)crotonate, N-(2-Pyrimidyl)-3-(methylamino)crotonamide, and N-(4-Methyl-2-pyridyl)-3-(methylamino)crotonamide
Authors: Kondo Michio 
Published: July 2006

Abstract
It has been found, from the 1H NMR spectra that two esters exist in an intramolecularly hydrogen bonded form (Z) in CDCl3 and DMSO solutions. Two amides, on the other hand, have been found to exist as a mixture of the Z and E isomers in DMSO solutions. H/D exchange at the olefinic site has been found to occur by the addition of D2O to the DMSO solutions of the amides, but not in the cases of the esters. The amide configurations are discussed. An interpretation of the 13C NMR spectra of these compounds is also given.
The Decomposition of N,N-Dichlorourethane by Copper: A Comparison with the Photolysis of Ethyl Azidoformate
Authors: Torimoto Noboru , Shingaki Tadao , Nagai Toshikazu 
Published: July 2006

Abstract
The reactions of N,N-dichlorourethane (1) with substrates, such as hydrocarbons and ethers, gave N-substituted urethanes (3) and urethane (4) in the presence of copper or copper(I) chloride. The reactions with aromatic hydrocarbons and cyclic ethers possessing an alkyl group at the α-position, however, gave no azepine and no alkoxyurethane respectively, in contrast to those of ethoxycarbonylnitrene generated from the azide. The reactions with the tertiary C–H bonds of cis- and trans-1,4-dimethylcyclohexanes proceeded non-stereospecifically, contrary to those of the nitrene. The reactions with alcohols led to high yields of 4, accompanied by the corresponding aldehydes, but afforded no O–H insertion product. The addition of a radical inhibitor, nitrobenzene, reduced the yield of 3, while it had no appreciable effect on the yield of 4. Furthermore, the reactions of N-chlorourethane with hydrocarbons also gave 3 and 4. These results suggest that the reaction of 1 with substrates proceeds not by a nitrene mechanism, but by a metal-radical mechanism.
Synthesis of [2-Serine, 8-VaIine]-Human Calcitonin
Authors: Nozaki Sukekatsu 
Published: July 2006

Abstract
The [2-serine, 8-valine]-analog of human calcitonin (1) was synthesized by the liquid phase method. Analog 1 was built up from five fragments with minimized protection for the side functional groups. These fragments were linked step wise to the C-terminal fragments by the azide method. A gel filtration was effectively applied for the purification of the resulting pep tide in each fragment condensation. Analog 1 had about the same hypocalcemic activity as that of human calcitonin. The result showed that the high activity of eel or salmon calcitonin 1 or 2 is not ascribable only to the amino acid sequence of their N-terminal decapeptide.
Cycloaddition Reactions of Thioacylketene Thioacetals and N-Thioacyldithioimidocarbonates
Authors: O-oka Masaharu , Kitamura Akihide , Okazaki Renji , Inamoto Naoki 
Published: July 2006

Abstract
Thioacylketene thioacetals (7) and N-Thioacyldithioimidocarbonates (8) undergo 1,4-cycloaddition reactions with active acetylenes and olefins to give six-membered heterocycles. Tetracyanoethylene behaves in a different way to afford conjugated dienes. In the reactions with diphenylketene and diazo compounds, 7 and 8 undergo different types of reactions; 7 gave products derived from 1,2-cycloaddition to the C=S bond, while 8 afforded 1,4-cycloadducts. Compound 7 was found to be more reactive than 8. The reactivity difference between 7 and 8 is discussed.
Fluorescence Spectra of 2-Pyridylbenzimidazoles. A Specific Interation of 2-(2-Pyridyl)benzimidazole with Ethanol
Authors: Kondo Michio 
Published: July 2006

Abstract
The fluorescence spectra of 2-(2-pyridyl)- (1a), 2-(3-hydroxy-2-pyridyl)- (1b), 1-methyl-2-(2-pyridyl)-, 2-(3-pyridyl)-, and 2-(4-pyridyl)-benzimidazole have been studied, and it has been found that their intensities are very strong, except for an ethanolic solution of 1a. It is likely, therefore, that a specific interaction, probably a bridge-type complexation of 1a with an ethanol molecule where imidazolic proton is explicitly involved, is responsible for the observed reduction in the fluorescence intensity for ethanol solutions. The fluorescence emission with a large Stokes’ shift of 1b is very strong, in ethanol as well as in other organic solvents tested, indicating a faster intramolecular proton transfer in the excited singlet state than intermolecular deactivation relaxation with ethanol molecules.
Charge-transfer Model in Considering the Reactivity of Heteroaromatic Nitriles with the Enolate Anion
Authors: Yamakawa Masumi , Kubota Tanekazu , Terui Yoshihiro , Honma Tsunetoshi , Tada Yukio 
Published: July 2006

Abstract
The reactivity of heteroaromatic nitriles with the enolate anion to give the enamino ketones was discussed on the basis of a reaction index calculated by the chargetransfer model and also using the total electron densities. The results were reasonable in interpreting the reaction mechanism.
The Raman Spectra of Diazines Adsorbed on Silicas
Authors: Yamamoto Yoichiro , Yamada Haruka 
Published: July 2006

Abstract
The Raman spectra of three diazines adsorbed on silicas have been measured. Spectra changes upon adsorption are interpreted as the result of hydrogen-bond formation between the surface OH group and the N atom of diazine. The order of the shifts of the Raman bands between three diazines is: 1,3-diazine&gt;1,4-diazine&gt;1,2-diazine.
Homoconjugation in BicycIo[3.2.1]octa-3,6-dien-2-yl and 6,9-Dihydro-5,9-methano-5H-benzocyclohepten-6-yl Radicals as Studied by Electron Spin Resonance
Authors: Kawamura Takashi , Takeichi Yoh’ichiro , Hayashida Shigeru , Sakamoto Masaaki , Yonezawa Teijiro 
Published: July 2006

Abstract
The radicals in the title and the bicyclo[3.2.1]oct-3-en-2-yl radical are examined with ESR. The extent of the odd electron delocalization due to π-π homo-conjugation in the bicyclo[3.2.1]octa-3,6-dien-2-yl radical is estimated to be in the order of a few per cent.
Complex Isomerism in 7-Methylbenzo[a]phenazinium Tetracyano-p-quinodimethanide
Authors: Matsunaga Yoshio 
Published: July 2006

Abstract
7-Methylbenzo[a]phenazinium tetracyano-p-quinodimethanide is dark green when it is prepared in boiling ethanol and violet when it is prepared in acetonitrile. Examination of the electronic, vibrational, and ESR spectra revealed that the former form is essentially non-ionic, and the latter, ionic.
Gas-chromatographic Measurements of Nitrous Oxide(N2O) in Air Using a Molecular Sieve Trap
Authors: Hirota Michio 
Published: July 2006

Abstract
The atmospheric mixing ratio of N2O was measured at the MRI, Koenji (Tokyo), between May and September, 1977, by a gas-chromatographic method. The mean value was 0.327 ppm. Judging from the measurements over the last 10 years, the atmospheric N2O seems to have increased about 20%.
(Hydroxyalkyl)pyridines as Bifunctional Catalysts. Dehydrobromination of 7-Bromocholesterol
Authors: Tachibana Yoji 
Published: July 2006

Abstract
In the dehydrobromination of 7-bromocholesterol, the reactions catalyzed by 2- and 3-(hydroxyalkyl)pyridines afforded 5,7-diene and 4,6-diene as the main product, respectively. The relative isomer ratio has been related to the position of the hydroxyalkyl group of the (hydroxyalkyl)pyridines. The results have been interpreted in terms of a concerted mechanism through a cyclic intermediate.
Reversible Oxygen Transfer Reactions between Sulfoxides and Sulfides. Relative Stabilities of Acyloxysulfonium Ions
Authors: Tanikaga Rikuhei , Nakayama Koji , Tanaka Kazuhiko , Kaji Aritsune 
Published: July 2006

Abstract
Sulfides and acyloxysulfonium ions generated from sulfoxides and trifluoroacetic anhydride undergo a reversible reaction at −80 °C. The acyloxysulfonium ions with electron-donating groups or less bulky groups were found to be more stable than those having electronwithdrawing or bulky substituents.
Preparation of Fluorinated Imidazole Derivatives Using Hexafluoro-1,2-epoxypropane
Authors: Hammoudat Hamdy A , Ishikawa Nobuo 
Published: July 2006

Abstract
Utilizing the reactivity of hexafluoro-1,2-epoxypropane, several new fluorine-containing imidazole derivatives were prepared. The reactions involve 2-mercaptobenzimidazole, 2-mercapto-4,5-diphenylimidazole, 2-imidazolidinethione, and 2-aminobenzamide.
The Nucleophilic Substitution Reaction of 1-Halogeno-2-methylsulfonylphenazine 5-Oxides
Authors: Tada Masao 
Published: July 2006

Abstract
The halogen atom in 1-halogeno-2-methylsulfonylphenazine 5-oxide is reactive toward the anionoid reagents through the activating effects of both the sulfone group and the N-oxide group. By the nucleophilic substitutions, some 1-substituted 2-methylsulfonylphenazine derivatives have been prepared in high yields.
The Bimolecular Reduction of Acridine and 9-Substituted Acridines by Sodium 1-Benzyl-1,4-dihydronicotinamide-4-sulfinate
Authors: Inoue Hiroo , Sonoda Ichiro , Inoguchi Nobuaki , Imoto Eiji 
Published: July 2006

Abstract
Sodium 1-benzyl-1,4-dihydronicotinamide-4-sulfinate is found to undergo the bimolecular reduction of acridine or 9-substituted acridines to the corresponding 9,9′-biacridans.
Structures of Copper(II) Complexes Which Deposit Copper in Chemical Copper-plating Bath
Authors: Ohno Seigo 
Published: July 2006

Abstract
The deposition of copper from alkaline solutions containing various copper(II) complexes and formaldehyde was studied. It was found that one-to-one copper(II) complexes of hepta-, hexa-, and quadridentate ligands deposit copper on reduced platinum by means of autocatalytic reduction, and that, under particular conditions, copper(I) oxide is deposited on oxidized platinum from the solutions containing quadridentate ligands.
Correlation of Solvation Free Energy of Electron with Empirical Parameters of Solvents. A Criterion for Electrophilic Effects of Solvents
Authors: Imai Hideo , Yamashita Kazuo 
Published: July 2006

Abstract
The solvation free energy of electrons in N,N-dimethylformamide, methanol, and water was estimated by means of electron photoemission into solution, and the data were compared with empirical parameters such as thermodynamic quantities, structural and kinetic parameters of solvents. It was confirmed that the interaction of an electron with solvent molecules is purely electrostatic and that the solvation free energy can be used as a tentative criterion of electrophilic properties of solvents.
Metal-ion Complexation of Noncyclic Poly(oxyethylene) Derivatives. Complexation in Aprotic Solvent and Isolation of Their Solid Complexes
Authors: Yanagida Shozo , Takahashi Kazutomo , Okahara Mitsuo 
Published: July 2006

Abstract
The interaction of homogeneous polyethylene glycol(PEG) (EOn, n=1–8) with the alkali and magnesium metal cations and the ammonium cation was investigated on the basis of 1H NMR(PMR) downfield shifts in acetone-d6 or in acetonitrile-d3 The specific complexations of EO4 with Mg2+, EO6 with Na+ and Ca2+, and EO7 with K+ were demonstrated by PMR studies, and their solid complexes were isolated. No specific interaction was detected for Rb+ and Cs+ in PMR studies. The magnesium ion interacts strongly with 15-crown-5, 18-crown-6, and PEG in acetone, and the Mg(SCN)2-EO4 and the Mg(SCN)2-above crown ether complexes were isolated. The terminal hydroxyl groups of PEG play an important role in the complexation with Li+ and Mg2+ in acetone. The formation of the 1 : 1 complex with Ca(SCN)2 was observed both for EO6 and for EO7. Strontium and barium thiocyanates formed solid complexes with PEG(EOn, n=2–8) and with glymes(tri- to octaglyme). Some novel complexes of 12-crown-4 and 15-crown-5 with NaSCN and Ca(SCN)2 were also isolated . The mechanism of metal-ion complexation of poly(oxyethylene) derivatives is discussed in terms of the coordination geometry.
Environment Effect on the Symmetry of Yang’s Biradical
Authors: Mukai Kazuo 
Published: July 2006

Abstract
The ESR spectrum of Yang’s biradical, which has a structural three-fold symmetry and degenerate, partially filled levels, has been measured in several solvents at 77 K. The results of the analyses of the ESR spectra have shown that Yang’s biradical must lack a three-fold symmetry in frozen solutions. The notable solvent effects observed for the zero-field splitting parameters (D and E) suggest that the asymmetric environment due to frozensolvent molecules contributes to the molecular distortion found for Yang’s biradical.
Monolayer Properties of Mixtures of Poly(octadecyl methacrylate) and Poly(butyl methacrylate) and Their Corresponding Copolymers
Authors: Yoshikawa Satoshi , Ueno Minoru , Meguro Kenjiro 
Published: July 2006

Abstract
The monolayer properties of mixtures of poly(octadecyl methacrylate) and poly(butyl methacrylate) have been compared with those of their corresponding copolymers of octadecyl methacrylate and butyl methacrylate, using the measurements of their surface pressure-area isotherms at the air/water interface at 20 °C. The results showed that the isotherms of the mixed monolayers had three break points, and the surface pressures of the lower two break points agreed with those of poly(butyl methacrylate). This suggests that at lower surface pressures, the mixtures of the two homopolymers are compatible in a bidimensional state when each phase contains a small amount of the other homopolymer, and otherwise these are incompatible, while at higher surface pressures, up to 70 segment mol% of poly(octadecyl methacrylate) they are incompatible and above 80%, they are compatible. The copolymers showed characteristic isotherms different from those of the mixtures. The properties of the copolymers in the bidimensional state are affected by variations in the vitrified, liquid, or crystalline states with an increase in the mean lengths of the side chains in the three-dimensional state.
The Study of Solutions of Alkali Halides in Acetone by Means of Vapor-pressure Osmometry and Conductometry
Authors: Lee Ha Chung , Miyahara Yutaka 
Published: July 2006

Abstract
Vapor-pressure depressions and electric conductivities at 40.3 °C have been measured for LiCl, LiBr, NaI, KI, and RbI in acetone. The greatest care has been taken to minimize the contact of salts and their solutions with air. In order to account for the data of vapor-pressure osmometry (VPO) for lithium salts in acetone, the dissociation-association equilibria of the salts, MX, expressed as
M++X−\ightleftharpoonsMX\ightleftharpoons1⁄2(MX)2
are proposed. The analysis of the conductance data of LiCl and LiBr, without considering the dimerization of the salts, leads to irrationally large values of the ionic association constants. For LiCl, NaI, and KI, VPO and conductometry give similar values of the dissociation constants, while for LiBr and RbI the agreement is not so satisfactory, though still within a factor of ten.
Crystal Structures of Dichlorobis(azocyclohexane)palladium(II) and Dichlorobis(azoisopropane)palladium(II)
Authors: Yamane Takashi , Ashida Tamaichi , Suzuki Hiroharu , Itoh Kenji , Ismi Yoshio 
Published: July 2006

Abstract
The structures of dichlorobis(azocyclohexane)Pd(II) and dichlorobis(azoisopropane)Pd(II) have been determined. The crystallographic data are: dichlorobis(azocyclohexane)Pd(II), Im3, a=16.538(2)Å, Z=6, R=8.9% for 667 reflections; dichlorobis(azoisopropane)Pd(II), Pbca, a=7.461(1), b=17.096(1), c=14.784(1)Å, Z=4, R=6.8% for 1451 reflections. In dichlorobis(azocyclohexane)Pd(II), a disorder occurs at the azo group, and the coordination mode of the ligand is not clear. The structure of dichlorobis(azoisopropane)Pd(II) agrees with that of dichlorobis(azobenzene)Pd(II).
The Gas Chromatographic Analysis of Bis(chloromethyl) Ether in Air
Authors: Baba Yoshio , Tanaka Toshiyuki 
Published: July 2006

Abstract
Bis(chloromethyl) ether was converted into bis(ethylthiomethyl) ether by a reaction with sodium ethanethiolate in a hexane solution; the latter sulfur-containing compound was then analyzed by means of a gas chromatograph equipped with a flame photometric detector.
The Micellar Acceleration of the Reduction of Nitroblue Tetrazolium by Superoxide Anion Radicals during the Autoxidation of Polyphenols
Authors: Takabe Teruhiro , Miyakawa Masako , Nikai Sueki 
Published: July 2006

Abstract
The rates of the reduction of Nitroblue Tetrazolium by O2− during the autoxidation of pyrogallol, epinephrine, and catechol were increased 110, 55, and 37-fold respectively in the presence of hexadecyltrimethylammonium bromide. A nonionic micelle of polyoxyethylene dodecyl ether also accelerated these reactions. The microenvironment effects on the electron-transfer from O2− to Nitroblue Tetrazolium were discussed.
Mixed Ligand Complexes Derived from the Reactions of Diaquabis-(3-hydroxy-2-methyl-4-pyronato)-cobalt(II), -nickel(II), and -zinc(II) with Pyridine and 4-Substituted Pyridines
Authors: Morita Hideyoshi , Shimomura Shigeru , Kawagughi Shinichi 
Published: July 2006

Abstract
The pyridine(py), 4-methylpyridine(4-Me-py) and 4-cyanopyridine(4-CN-py) adducts of bis(3-hydroxy-2-methyl-4-pyronato) complexes (ML2) of cobalt(II), nickel(II), and zinc(II) have been synthesized: CoL2(py)n (where n=2 or 3), NiL2(py)3, ZnL2(py), ML2(4-Me-py)2 (where M=Co(II), Ni(II), and Zn(II)), ML2(4-CN-py) (where M=Co(II) and Zn(II)), and NiL2(4-CN-py)2. Based on the magnetic, spectral, and thermogravimetric data, three of these complexes, ZnL2(py) and ML2(4-CN-py) (where M=Co(II) and Zn(II)), are presumed to have a five-coordinate structure, while the other complexes are presumed to be octahedral. In the case of the 4-cyanopyridine complexes, the infrared spectra show that the pyridine-ring nitrogen is linked to the metal ion and that the nitrogen atom of the nitrile group is not coordinated.
The Computer-assisted Characterization of Terpenes and Related Compounds by the Use of Combined Spectrometric Data
Authors: Sasaki Shin-ichi , Abe Hidetsugu , Saito Keiji , Ishida Yoshiaki 
Published: July 2006

Abstract
Basic research to prepare a combined retrieval system based on three different sets of spectrometric data, infrared, mass, and 1H NMR, for terpenes and related compounds is described. The system may be used either for searching all three types of spectra, for two, or for one only. The results of 112 test searches are presented. The combined method is proved to be a good tool for the identification of such compounds, especially those in a structurally close relationship.
The Partition Mechanism of Thenoylacetone and Thenoyltrifluoroacetone in Water/Alcohol Systems
Authors: Suzuki Nobuo , Shibuya Hidenori , Watarai Hitoshi 
Published: July 2006

Abstract
The apparent partition coefficients of thenoylacetone (TA) in ten alcohol/water systems and the enol fractions of TA in both phases were determined. Comparing the results with those of thenoyltrifluoroacetone (TTA), the substituent effect of methyl and trifluoromethyl groups on the partition behavior of the β-diketones in the alcoholic partition systems was examined. The experimental results showed that the apparent partition coefficient of TA is larger than that of TTA, while the partition coefficient of the enol form of TA is smaller than that of TTA. This was related to the differences in the partitioning species of TA and TTA; that is, TA is in keto and enol forms, while TTA is in enol, hydrate, and hemiacetal forms. The partition coefficient of each species was discussed in terms of the solubility parameter of alcohol.