bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Arylethylenesulfonamides and Intramolecular Rearrangement of N-(Arylethylenesulfonyl)thioureas
Authors: Hasegawa Kiyoshi , Hirooka Syuzi , Sasaki Tadashi 
Published: July 2006

Abstract
The reactions of p- and p′- substituted N-(2,2-diarylethylenesulfonyl)- (8), N-[2-phenyl-2-(α-naphthyl)ethylenesulfonyl]- (9), and N-(p-nitrostyrene-1-sulfonyty)-N′-alkylthioureas (12) with bases afforded new intramolecularly rearranged N-alkyl-S-(2,2-diarylvinyl)- (13), N-alkyl-S-[2-phenyl-2-(α-naphthyl)vinyl]- (14), and N-alkyl-S-(p-nitrostyryl)isothioureas (15), respectively, p- and p′-Substituted 2,2-diarylethylene-N-methylsulfonamides (6) were treated with carbon disulfide and alkyl halides in the presence of a base to give alkyl 2,2-diarylvinyl trithiocarbonates (17). The order of reactivity of the sulfonylthioureas and -amides indicates that the rearrangement is retarded by electron-releasing p-substituents on benzene rings (Cl&gt;H&gt;CH3&gt;OCH3).
Electron-transfer Kinetics of Transition-metal Complexes in Lower Oxidation States. Part III. Electrochemical Rate Constants for the Fe(II)/Fe(I) Redox Systems
Authors: Saji Tetsuo , Yamada Tamaki , Aoyagui Shigeru 
Published: July 2006

Abstract
The standard rate constants for the redox systems Fe(II)/Fe(I) are measured. They are about one tenth of those for the systems Fe(III)/Fe(II) and Cr(I)/Cr(0). The difference in the kind of molecular orbital occupied by the excess electron of the reductant species can account for the difference in the rate constant.
The Cycloaddition Reaction of Isobenzofuran with Fulvenes: The Formation of an endo-(6+4)π Adduct
Authors: Takeshita Hitoshi , Mori Akira , Sano Sansei , Fujise Yutaka 
Published: July 2006

Abstract
Isobenzofuran (I) was shown to react at 160 °C with 6,6-diphenylfulvene to give two endo-(2+4)π cycloadducts, an endo-1: 1-adduct and an endo-anti-endo-1: 2-adduct. On the other hand, I and 6,6-dimethylfulvene gave an endo-(6+4)π cycloadduct at room temperature.
The Reflection Spectra of Complex Salts of the Tetracyanoquinodimethane Anion Radical
Authors: Oohashi Yukako , Sakata Tadayoshi 
Published: July 2006

Abstract
Reflection measurements of the pressed pellets of two 2 : 3 complex salts and six 1 : 2 complex salts of the tetracyanoquinodimethane (TCNQ) anion radical were carried out over the 5000–43000 cm−1 range by the use of Avery’s method. The polarized normal-incidence reflection was measured for the Ph3PCH3(TCNQ)2single crystal. The observed results were examined on the basis of the composite-system method. For 2 : 3 salts, the transition energy and the oscillator strength are interpreted by the use of the N-A-A model (N: TCNQo and A-A: TCNQ anion dimer); it is concluded that the interaction between the two components, N and A-A, is weak. In the solid-state spectra of 1 : 2 salts, the assignments were made by the use of the polarization results of the normal-incidence reflection of the Ph3PCH3(TCNQ)2 crystal. Besides the four transitions corresponding to those of 2 : 3 salts, two new CT bands with weak intensities were observed and assigned. Except for quinolinium(TCNQ)2, a spectral change correlative to the electrical conductivity was found in the 1 : 2 salts and discussed in relation to the extent of the delocalization of the negative charge of (TCNQ)2−. The spectrum of quinolinium(TCNQ)2 exhibits a remarkable intensity decrease compared with those of the other 1 : 2 salts.
Effects of Electrolytes on Properties on Black Films and Foam Stability of Aqueous Nonionic Surfactant Solutions
Authors: Yamanaka Teruko 
Published: July 2006

Abstract
The properties of black film, the surface tension of solution and the foam stability in the aqueous solutions of polyoxyethylene-type nonionic surfactants containing various electrolytes were studied. The additional tension \barΔ of black films showed a maximum and a minimum in the concentration range of electrolytes of 1×10−5–1 N. The concentration at this minimum shifted in accordance with the lyotropic series of anions. The surface tension was unaffected by the electrolyte of the concentration less than about 1×10−2 N, whereas \barΔ exhibited a maximum in this range. The overall rate of growth of the black film was found to be proportional to \barΔ over a wide range of electrolyte concentration. The effects of electrolytes on the foam stability were discussed being based upon the properties of the black films.
The Fluorometric Determination of Gallium in Aluminum Metal with 8-Quinolinethiol
Authors: Watanabe Kunihiro , Kawagaki Ky\={o}z\={o} 
Published: July 2006

Abstract
A method for the fluorometric determination of gallium in aluminum metal is presented which involves extraction with the methyl isobutyl ketone (MIBK) of the gallium 8-quinolinethiolate complex. The extracted complex has a greenish-yellow fluorescence, with an emission maximum at 505 nm. The maximum fluorescence intensity is obtained at a pH of the initial aqueous phase of around 3.3; the fluorescence remains stable for at least 2 hr. When 50 ml of a sample aqueous solution containing gallium and 0.2 ml of a 0.2% 8-quinolinethiol solution is subjected to extraction with 10 ml of MIBK, the quantity of gallium which can be present for determination in the sample solution amounts to 1 to 30 μg. For the removal of the interfering effects of zinc, cadmium, copper, and nickel on the fluorometric determination, gallium was extracted with isopropyl ether from a 7 M HCl solution. The relative error of this method was 5% for 0.019% gallium in aluminum metal.
Studies on the Hexagonal Hydrate of Molybdenum Trioxide. The Physical Properties of the Hydrate and Its Changes on Heat Treatments in Air, in Hydrogen, and in a Hydrogen–thiophene Mixture
Authors: Sotani Noriyuki 
Published: July 2006

Abstract
The hexagonal hydrate (I) of molybdenum trioxide, which has been newly found and reported, was studied by X-ray diffraction analysis, IR and NMR spectroscopies, and by other methods. Also studied was the change in (I) on heat treatments in air, in hydrogen, and in a hydrogen–thiophene mixture. The crystal was found to belong to a hexagonal system. The air-dried sample has about 0.46 mol of water. This water is included as a water molecule, not as hydroxyl. By the dehydration of (I), anhydrous molybdenum trioxide (I′), which has the same crystal structure as (I), is obtained. Another new form of (I′) is the hexagonal trioxide, which is hygroscopic and which easily absorbs water when standing in air. This (I′) is metastable and is irreversibly transformed to rhombic molybdenum trioxide(II) at 420–430 °C. In hydrogen and in a hydrogen-thiophene mixture, reduction and sulfurization occur in addition to transformation, which can be shown schematically as: (Remark: Graphics omitted.). Transformation in hydrogen and in the hydrogen–thiophene mixture proceeds faster than in air. Reduction occurs more quickly in the hydrogen–thiophene mixture than in hydrogen.
Studies of the Preparation and Physical Properties of Multivalent Metal Condensed Phosphates. Part XI. The Preparation of Various Aluminum Phosphates and Their Thermal Transformation
Authors: Tsuhako Mitsutomo , Hasegawa Kazuko , Matsuo Tsuneo , Motooka Itaru , Kobayashi Masamitsu 
Published: July 2006

Abstract
In the reaction of Al2O3 or Al(OH)3 with phosphoric acid, the conditions of the formation of the I and II types of aluminum dihydrogen tripolyphosphate, AlH2P3O10, and the A and B types of aluminum tetrametaphosphate, Al4(P4O12)3, were established. The I and II types of AlH2P3O10 were chiefly obtained at 300 °C; the formation of the I type predominated when the water content of the primary product was 15–30%, while the II type was more readily formed at a water content of 10–15%. Also, the I and II types were easily formed at vapor pressures of 1–5 atm. Al4(P4O12)3 was produced when the water content was less than 10% or more than 30%. On the other hand, the A and B types of Al4(P4O12)3 were easily formed at 500 °C; the A type was chiefly formed when the water content was below 10% or above 25%, while the B type was produced at the water content of 10–25%. The water content of the primary product is presumably due to the dehydration caused by the condensation of the P–OH. Thus water, effective for the formation of aluminum phosphates, is the structural water (P–OH). Further, the B type was liable to be formed on rapid dehydration, while the A type was more readily produced on slow dehydration. Accordingly, the formation of aluminum phosphate has been confirmed to be greatly dependent on the water content of the primary product and on the vapor pressure in the secondary heat treatment.
The Reaction of Aroyl Alkyl Carbonates with Isocyanates
Authors: Uchida Yuzuru , Kozuka Seizi 
Published: July 2006

Abstract
Aroyl alkyl carbonates were treated with isocyanates with or without addition of sodium methoxide and alkyl N-aroylcarbanilates were obtained as the major products. Based on 18O tracer study and catalytic effect of alkoxide ion, a base catalyzed ionic reaction process was confirmed for the mechanism of the carbanilate formation.
The Mannich Reaction of Alicyclic α-Diketones. A Novel Synthesis of 2-Hydroxy-3-methyl-2-cyclohexen-1-one
Authors: Ohashi Masao , Takahashi Tadashi , Inoue Seiichi , Sato Kikumasa 
Published: July 2006

Abstract
A new synthesis of 2-hydroxy-3-methyl-2-cyclohexen-1-one (1) is described. The Mannich reaction of cyclohexane-1,2-dione (2) or 2-morpholino-2-cyclohexen-1-one (3) with morpholine and formalin gave a Mannich base (4), which was then hydrogenolized to afford 1. However, the Mannich reaction of 1 merely gave a bis-Mannich base (22), which was then similarly hydrogenolized to afford 3,6-dimethyl-2-hydroxy-2-cyclohexen-1-one (7) along with 3,6-dimethyl-2-hydroxy-6-morpholinomethyl-2-cyclohexen-1-one (26); 2-hydroxy-3,6,6-trimethyl-2-cyclohexen-1-one could not be obtained under these conditions. The Mannich reaction of other alicyclic α-diketones and the hydrogenolysis of their Mannich bases are also described.
Coenzyme Models. II. Effect of Micellar Environments on the Acid-Catalyzed Hydration of 1,4-Dihydropyridine Derivatives
Authors: Shinkai Seiji , Ando Reiko , Kunitake Toyoki 
Published: July 2006

Abstract
An effect of micelles on the acid-catalyzed modification reaction of two dihydropyridines is reported in connection with the NADH function bound to alcohol dehydrogenase, and the hydration equilibrium of dihydronicotinamides was found to be quite susceptible to the ionic environment. The absorption maximum at 357 nm of 1-benzyl-1,4-dihydronicotinamide(NBzNH) was not affected by the presence of cationic micelles, while that of 1-lauryl-1,4-dihydronicotinamide(NLaNH) shifted by 5–6 nm to shorter wavelengths, probably due to the neighboring cationic charge. The hydration rates for dihydronicotinamides were prompted by NaLS micelle and retarded by CTAB micelle. The rate augmentation in the NaLS micelle, compared with the non-micellar system, was 1.7-fold for NBzNH and 33-fold for NLaNH. On the other hand, CTAB micelle pronouncedly depressed the hydration rate of NLaNH, which is 414-fold slower than in NaLS. The micelle of 1-lauryl-3-carbamoylpyridinium(NLaN), which forms the charge transfer complex with NLaNH, was found to inhibit the acid-catalyzed hydration more efficiently (1400-fold slower). Thus, it is suggested that the ammonium ion adjacent to the dihydronicotinamide group in alcohol dehydrogenase–NADH complex performs some biological functions.
Reaction of Group IV Organometallic Compounds. XXXII Modified Synthesis of Imidazolidines with N,N′-Bis(trimethylsilyl)-1,2-diamines
Authors: Suzuki Hiroharu , Ohashi Masayasu , Itoh Kenji , Matsuda Isamu , Ishii Yoshio 
Published: July 2006

Abstract
N,N′-Bis(trimethylsilyl)-1,2-diamines gave imidazolidine derivatives accompanied with the elimination of hexamethyldisiloxane in excellent yields by condensation reactions with carbonyl compounds under mild conditions. These reactions are regarded as the typical addition-elimination reaction of group IV organometallics.
The Photovoltaic Effect in Naphthacene–Gold Layers
Authors: Matsumura Michio , Uohashi Hiromichi , Furusawa Masaki , Yamamoto Naoto , Tsubomura Hiroshi 
Published: July 2006

Abstract
The photovoltaic effect in gold–naphthacene thin layers has been studied. By excitation in the region of the visible absorption band of naphthacene (2.4–3.0 eV), it was found that the photovoltage consists of two components; one with a short response time, caused by the electron transfer across the boundary between gold and naphthacene, and the other with a long response time, attributable to a diffusion process in the naphthacene film. The lifetime of carriers produced by the former process was estimated to be 0.08 s at least, decaying by the recombination of trapped holes in naphthacene with electrons in gold. Photovoltage was also observed in a region of wavelengths greater than the visible absorption band of naphthacene.
ESR Studies of the Structures and Spin-exchange Interactions of the Dimers of Nitro-substituted Salicylaldehyde Schiff-base Complexes of Copper(II) in Frozen Solutions
Authors: Chikira Makoto , Isobe Taro 
Published: July 2006

Abstract
The computer simulations of the ESR spectra for the triplet-state dimers of the title complexes in frozen solutions revealed that the dimeric structures change markedly upon nitro-substitutions at the positions of 3 or 5 in the phenyl-rings of the Schiff bases. It was also found that some of these nitro-substituted copper(II) complexes form 1: 1 molecular complexes with bis(N-salicylideneisopropylaminato)copper(II) in toluene. The dependence of the ESR spectral intensities for the ΔM=2 transitions upon the temperature in the range of 1.57–4.2 K indicated that the intra-dimer spin-exchange interactions are weakly anti-ferromagnetic (0.7–2.2 cm−1).
Photochemistry of peri-Substituted Naphthalenes. I. Photochemistry of Dimethyl 1,8-Naphthalenediacrylate
Authors: Honda Koichi , Yabe Akira , Tanaka Hideaki 
Published: July 2006

Abstract
The photochemical reactions of dimethyl 1,8-naphthalene diacrylate (I) in solution are found to be cis,trans isomerization and concomitant intramolecular cycloaddition through a triplet state (ET is ca. 40 kcal/mol). Cyclization reaction gives naphtho[1′,8′]bicyclo[3.1.1]hept-2-ene-6-exo,7-endo-dimethyl dicarboxylate (VI), its 6-endo, 7-endo substituted isomer (VII) and cis-anti-naphtho[1′,8′]bicyclo[3.2.0]hept-2-ene-6,7-dimethyl carboxylate (II) in a ratio of ca. 85: 10: 5. Predominant formation of crossed adducts is discussed, taking into consideration the ground-state conformations of (I). Biradical mechanism is proposed for the cyclization to explain the stereochemistry of the crossed products.
The Formation and Structure of Copper(II) Complexes with Cyclodextrins in an Alkaline Solution
Authors: Matsui Yoshihisa , Kurita Toyoaki , Yagi Masao , Okayama Tetsuo , Mochida Kazuo , Date Yoshio 
Published: July 2006

Abstract
Copper(II) forms a 2: 1 complex with cyclodextrin in an alkaline solution. The complexes with α- and β-cyclodextrins were isolated from solutions by the addition of ethanol. They are labile, and, upon heating, the Cu(II) is reduced to Cu(0). The role of the hydroxide ion was examined by means of potentiometrie and conductometric titrations; it was found that the reaction of 1 mol of α-cyclodextrin with 2 mol of Cu(OH)2consumes 2 mol of the hydroxide ion, whereas 3 mol of the hydroxide ion are consumed for the reaction of β-cyclodextrin. Polarimetric measurements showed that the optical rotation of cyclodextrin changes from dextrorotatory to levorotatory upon the formation of the Cu(II)-cyclodextrin complex. It was suggested, with a molecular model, that the two pairs of C2 and C3′ secondary hydroxyl groups of contiguous glucose units are cross-linked by the Cu(OH−)2Cu ion bridge in the α-cyclodextrin complex and by Cu(OH−)(O2−)Cu ion bridge in the β-cyclodextrin complex. Furthermore, the circular ring of cyclodextrin may be distorted to the ellipsoidal form by the complex formation, causing a pronounced change in the optical rotation.
Normal Vibrations of Benzenesulfonate and Benzene-d5-sulfonate Ions
Authors: Uno Toyozo , Kuwae Akio , Saito Yutaka , Machida Katsunosuke 
Published: July 2006

Abstract
Infrared and Raman spectra of sodium benzenesulfonate and its fully C-deuterated derivative have been recorded in the solid state and in the aqueous solution. The normal coordinate analysis has been made for C6H5SO3− and C6D5SO3− ions based on the C2V symmetry. A valence force field was assumed and the force constants were refined by the least squares method. It was found that the diagonal force constants for the CH out-of-plane bending vibrations at the ortho and the para positions are greater than the corresponding constant for the meta position. This result reflects well the effect of the electron attractive substituent in monosubstituted benzene derivatives. The force constants obtained were transferred to p-toluenesulfonate ion successfully.
The Proof of a Triplet Ground State in the N,N′-Di-t-butyl-m-phenylenebinitroxide Biradical
Authors: Mukai Kazuo , Nagai Hiroshi , Ishizu Kazuhiko 
Published: July 2006

Abstract
The magnetic susceptibility of the N,N′-di-t-butyl-m-phenylenebinitroxide biradical has been measured in the temperature range from 60 to 300 K. The susceptibility follows the Curie-Weiss law, with a paramagnetic Curie constant of 0.90±0.04 K·-emu/mol and a Weiss constant of −19±2 K. This susceptibility suggests that the ground state of the biradical is a triplet and that an intramolecular pure triplet approximation, 2J&gt;&gt;kT, is reliable in the temperature region below 300 K. The negative Weiss constant is due to the negative exchange interaction, J′&lt;0, between the triplets.
Studies of Bivalent Metal Chelates of 2-Aminomethylpyridine
Authors: Noji Masahide , Kidani Yoshinori , Koike Hisashi 
Published: July 2006

Abstract
Bivalent metal chelates of 2-aminomethylpyridine (abbreviated as 2AMP), M(2AMP)2X2 (M=Cu, Ni, Co, and Zn ion; X=Cl−, Br−, I−), were synthesized in ethanol. The magnetic moments and the diffuse reflectance spectra were measured. The Cu(2AMP)2X2 complexes (X=Cl− and Br−) were considered to have a monomeric distorted octahedral structure. The Ni(2AMP)2X2 complexes (X=Cl−, Br−, I−) were also suggested to have an octahedral structure. However, for Co(2AMP)2Br2 and Co(2AMP)2I2 a tetrahedral and a square planar structure were proposed on the basis of their magnetic moments of 4.20 and 2.78 B.M. respectively. The infrared spectra of the chelates were analysed in relation to their structures; a good relationship was found between the structures and the far-infrared spectra.
Induced Circular Dichroism of Benzyl Chromophores Bound to Helical Polypeptides
Authors: Nomori Hiroyuki , Tsuchihashi Nobuaki , Takagi Shoji , Hatano Masahiro 
Published: July 2006

Abstract
Extrinsic optical activity was observed for symmetric side chain chromophores in helical polypeptides. Poly-β-benzyl-l-aspartate, poly-β-p-nitrobenzyl-l-aspartate and poly-γ-p-nitrobenzyl-l-glutamate gave induced circular dichroism in the wavelength regions corresponding to the absorption bands of the benzyl and the p-nitrobenzyl chromophores of the side chains in their dilute solutions. Moreover, poly-γ-benzyl-d-glutamate gave induced circular dichroism due to the benzyl chromophore in its concentrated solutions which formed a liquid crystalline phase. The extrinsic optical activity thus observed was explained as the consequence of the loss of the rotational freedom of the chromophores relative to the α-helical structure and to the cholesteric helical structure of the polypeptides.
The Reaction of 1,2,4,5-Tetrazines with 2-Phenyl-1-azirine. The Synthesis of 2H-1,2,4-Triazepine Derivatives
Authors: Takahashi Masahiko , Suzuki Norimoto , Igari Yoshihiko 
Published: July 2006

Abstract
The Reaction of 3,6-disubstituted 1,2,4,5-tetrazines (1a–c) with 2-phenyl-1-azirine (2) afforded 3,7-disubstituted 6-phenyl-2H-1,2,4-triazepines (5a–c) in good yields.
ESR and ENDOR Studies of Hindered Internal Rotation of Higher Alkyl Groups in 4,4′-Dialkylbiphenyl Anion Radicals
Authors: Nemoto Fujito , Shimoda Fumio , Ishizu Kazuhiko 
Published: July 2006

Abstract
ESR and ENDOR spectra were obtained for the anion radicals of 4,4′-diisopropylbiphenyl, 4,4′-dicyclohexylbiphenyl and 4,4′-dicyclopentylbiphenyl. Both the β- and γ-proton coupling constants of the alkyl groups were precisely determined. The temperature dependence of the β-proton splittings of the alkyl groups were investigated. According to the Heller-McConnell relationship for hyperconjugation, a4β=(B0+B2cos2θ)ρ4π, the positive temperature dependence of the alkyl β-proton splitting was adequately interpreted utilizing a revised model with restricted rotation. The rotational potential barrier and the energy difference of the two equilibrium states obtained were 1.2 and 0.5, 1.2 and 0.6, and 1.2 and 0.6 kcal/mol for the 4,4′-diisopropyl-, 4,4′-dicyclohexyl-, and 4,4′-dicyclopentylbiphenyl anions, respectively. The energy difference of the non-bonding interatomic interaction was calculated in terms of the Lennard-Jones 6–12 potential. Excellent agreement is found between the experimentally-determined value of the potential barrier and that calculated theoretically. ENDOR observations carried out for 4,4′-dicyclohexyl- and 4,4′-dicyclopentylbiphenyl anion radicals in solution demonstrated that γ-protons revealed two different hyperfine coupling constants. These hyperfine coupling constants were assigned to the stereochemically different γ-protons. The ratio of these γ-protons splittings suggest that hyperconjugation plays an important role in producing a spin density of the γ-protons as has been proposed for explanations of the β-proton splittings.
The Photochemical Decomposition of Benzenediazonium o-Carboxylate in Several Solvents
Authors: Kato Masahiko , Tamano Taizo , Miwa Toshio 
Published: July 2006

Abstract
The photochemical decompositions of benzenediazonium o-carboxylate (1) in water, ethanol, acetone, and dichloromethane were studied. In every case, the initial loss of molecular nitrogen to give a zwitterion (3) and/or a diradical (4) was the primary process. In the solvents which are susceptible to hydrogen abstraction by a radical (ethanol and acetone), reduction takes place to give benzoic acid, through 4, in a good yield. In water, from which a hydrogen atom is less easily abstracted homolytically, salicylic acid was the main product (24%), while benzoic acid was the minor one (9%). In CH2Cl2, the reduction product (benzoic acid, 20%) and biphenylene (10%) were formed. The formation of the latter compound prompted us to study the photochemical decomposition of 1 in CH2Cl2 in the presence of tropone. This reaction gave cycloaddition products, (11) and (12), in 3.2 and 0.7% yields respectively.
Stereospecific [2π+2π+2π] Cycloaddition Reaction of Norbornadiene
Authors: Tabushi Iwao , Yamamura Kazuo , Yoshida Zen-ichi , Togashi Atsushi 
Published: July 2006

Abstract
[2π+2π+2π] cycloaddition reaction of cis- or trans-disubstituted olefinic dienophiles (4a–4e) to bicyclo[2.2.1]hepta-2,5-diene (1, norbornadiene) was found to be stereospecific. The cycloadducts obtained, 4,5-disubstituted tetracyclo[4.2.1.0.2,903,7]nonane (5,6) conserved the original stereochemistry in the dienophiles, strongly suggesting the presence of homo-conjugation in 1. A striking contrast between cycloaddition reaction of quadricyclane (a valence bond isomer of 1) and that of norbornadiene was understood by application of the principle of orbital symmetry conservation to these cycloadditions.
Kinetic Studies of the Thiol-catalyzed Rearrangement of N-Phenylsulfonyl Thione S-Imide
Authors: Tamagaki Seizo , Sakaki Keishi , Oae Shigeru 
Published: July 2006

Abstract
The N-phenylsulfonyl thione S-imide(I) of 1,2-dithiole-3-thione reacted catalytically with various thiols to afford the corresponding rearranged N-phenylsulfonyl-1,2-benzodithiole-3-imine(II) with the extrusion of the elemental sulfur together with a minor amount of reduced benzotrithione. A kinetic study of the rearrangement of I with thiobenzoic acid was performed, and a plausible mechanism is discussed.