bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Added Inorganic Salts on the Micelle Formation of Nonionic Surfactants in Aqueous Solutions
Authors: Nishikido Nagamune , Matuura Ryohei
Published: July 2006

In order to divide the inorganic salt effect on the micelle formation of nonionic surfactants into the effects on the hydrocarbon and on the hydrophilic moieties of the surfactant, the critical micelle concentrations(CMC) of nonionic surfactant homologs (8,10,12 methylene and 6 oxyethylene groups) were determined in aqueous salt solutions. The salt-effect parameters of methylene and hexa(oxyethylene) groups were calculated from the CMC data. The orders of both the parameters with respect to the anion obeyed the Hofmeister series. The variation in the extent of the parameters with respect to the cation was much less than that with respect to the anion. These phenomena were discussed in terms of the direct and indirect effects of ions on the water structure around the hydrocarbon and hydrophilic moieties of the surfactants. In addition, the salt effect on the cloud point (CP) and the amount of solubilization toward the Yellow OB dyestuff in aqueous solutions were discussed in connection with the salt effect on the hydrophilic moiety.
The Effective π-Electron Hamiltonian for the Excited State. The Effect of Σ-Π Interaction
Authors: Maki Izumi , Kitaura Kazuo , Nishimoto Kichisuke
Published: July 2006

The effective π-electron Hamiltonian for the excited molecule has been derived from the singly excited configuration interaction method (SECI) considering Σ-Π interaction. In this paper, the zero-differential overlap (ZDO) approximation has been employed. Then, in SECI scheme, π-π* and σ-σ* configurations interact through the exchange type MO-integrals over π- and σ-MO’s. As the result, only the excited singlet states are modified by Σ-Π interaction. So that the triplet states remain unchanged by this type of interaction.

When the ZDO approximation is employed, the effective electron interaction over AO’s, \ ildeγμν, can be derived. It is found that \ ildeγμν’s are represented approximately in terms of topological matrix, so named ‘bond index matrix’.
Studies of the Interaction of Excited Chloranil with Acrylonitrile, Methyl Methacrylate, and Styrene by Means of Laser Photolysis
Authors: Kobashi Harumichi , Gyoda Hitoshi , Morita Toshifumi
Published: July 2006

The behavior of electronically excited chloranil interacting with the titled vinyl compounds and solvents has been studied by means of the nanosecond laser photolysis technique. Semiquinone radicals and/or chloranil anions have been detected as transients except in the system containing styrene. Careful observation and analysis of the kinetic behavior of the transient absorptions reveal that these transients are brought about by the interaction of excited triplet state of chloranil with vinyl monomers and/or solvents. The logarithms of the quenching rate constants and rate constants of the formation of transients are linearly related to the ionization potentials of the vinyl monomers and solvents used. The mechanisms of the triplet quenching and transient formation can reasonably be interpreted by taking the relaxed triplet-state complex with a charge-transfer character into account as the precursor leading to the production of semiquinone radicals, chloranil anions, and other intermediate compounds.
The Structure of Ikarugamycin, an Acyltetramic Acid Antibiotic Possessing a Unique as-Hydrindacene Skeleton
Authors: Ito Shosuke , Hirata Yoshimasa
Published: July 2006

The structure and configuration of an antibiotic, ikarugamycin, have been established to be 1e on the basis of chemical reactions, especially of oxidative degradation. It is suggested that the as-hydrindacene skeleton arises biogenetically via an intramolecular Diels-Alder reaction.
New Method for the Preparation of Carboxylic Esters
Authors: Saigo Kazuhiko , Usui Masahiro , Kikuchi Kazunori , Shimada Eiichiro , Mukaiyama Teruaki
Published: July 2006

Various carboxylic esters including functionalized ones are prepared in good yields from equimolar amounts of free carboxylic acids and alcohols under mild conditions by the use of 2-chloro- or 2-bromopyridinium salt, a new and efficient coupling reagent.
The Effect of Water Vapor on Contamination of Metallic Oxide Surfaces
Authors: Tamai Yasukatsu , Matsunaga Toshiaki , Suzuki Kazutomi
Published: July 2006

The contamination rates of the clean surfaces of metallic oxides by liquid-paraffin vapor are largely reduced by the coexisting water vapor. They are related to the hydrophilicity of oxides evaluated as the water-solid interaction free energy by the two-liquid-contact-angle method.
Emission Spectra of CH(A2Δ) Produced from CH3CN in the Argon Flowing-Afterglow Reaction
Authors: Suzuki Kaoru , Kuchitsu Kozo
Published: July 2006

Emission spectra from CH(A2Δ) formed in the reaction of positive ionic species of argon with CH3CN were studied by the flowing-afterglow method. The rotational distributions for the v′=0, 1, and 2 of CH(A2Δ) are characterized by effective rotational temperatures of ca. 5000, 2000, and 1500 K, respectively, whereas the distributions in lower levels (N′\lesssim11), especially for v′=0, are characterized by that of ca. 700 K. The average vibrational and rotational energies distributed in the CH radicals produced initially are estimated to be 0.32±0.04 and 0.34±0.06 eV, respectively.
On the Phase Transition of Ammonium Hexafluoroferrate(III)
Authors: Moriya Keiichi , Matsuo Takasuke , Suga Hiroshi , Seki Syûzô
Published: July 2006

The heat capacities of (NH4)3[FeF6] crystal have been measured from 15 to 350 K with an adiabatic calorimeter. A heat capacity anomaly was observed at 267.02±0.05 K. The enthalpy and entropy changes of the transition are 6490±500 J mol−1 and 24.8±1.9 J K−1 mol−1, respectively. This value of entropy was discussed in terms of a model involving orientational disorder of the ammonium as well as hexafluoroferrate(III) ions. Based on the assumption of the average fcc symmetry of the crystal and internal rigidity of the ions, the proposed model predicts the transition entropy equal to R In 16=23.05 J K−1 mol−1 which is in close agreement with the experimental value. Temperature dependent splitting of the Raman band due to the internal vibration of the anion was found to be consistent with the model. The excess heat capacity follows the prediction of the Landau theory of phase transitions of the second kind. Properties of the present and the similar crystals including ammonium and alkali salts of hexafluoro-complex ions were discussed in terms of the ionic orientational disorder.
Deoxygenation of Nitrobenzene by Tributylphosphine in the Presence of Alcohols. Synthesis of 2-Alkoxy-3H-azepines
Authors: Masaki Mitsuo , Fukui Kiyoshi , Kita Junichiro
Published: July 2006

Deoxygenative reduction of nitrobenzene by tributylphosphine in the presence of primary or secondary alcohols gave 2-alkoxy-3H-azepines in good yields. The use of acidic hydroxylic compounds, such as phenol or acetylacetone, in place of the alcohols did not lead to ring enlargement. Triphenylphosphine could be used as a reducing agent, but the yields of the azepines were relatively low. 2-Alkoxy-3H-azepines were converted into 2-amino-3H-azepine in good yields by the reaction with ammonium carbonate. 2,3-Dihydro-1H-azepin-2-one was prepared by the hydrolysis of 2-butoxy-3H-azepine or 2-amino-3H-azepine.
Photochemical Reaction of Diphenylcyclobutenedione Derivatives. Formation and Reaction of Conjugated Bisketene and Its N-Analog
Authors: Obata Naruyoshi , Takizawa Takeo
Published: July 2006

The photolysis of diphenylcyclobutenedione derivatives (Va, b) under N2 and that in the presence of substrate, O2 or isocyanide, have been studied. The former resulted in the recovery of a large amount of V and the fragmentation; the latter gave the insertion products into V, diphenylmaleic anhydrides and iminocyclopentenones in good yield. The intermediates, bisketene and ketene-ketenimine as primary photo products were confirmed by the photolysis of Va in methanol to give succinates and by low-temperature IR-technique. Structural aspects of bisketene intermediate were discussed.
Determination of Micropore Volumes of Active Carbon Using Dubinin-Radushkevich Plots
Authors: Tsunoda Ryoichi
Published: July 2006

The adsorption of methanol on active carbons at 30 °C was carried out and a new method for determining the micropore volume in the Dubinin-Radushkevich plot is presented. From this method, it was found that the adsorption volume (V) corresponding to the adsorption potential (A=RTlnP0⁄P), at which the plot of dV⁄d(−A) vs. A has its minimum value, is the value of the micropore volume in cases where extrapolation of the Dubinin-Radushkevich plot cannot be applied because of non-linearity of the Dubinin-Radushkevich plot.
The Reaction of Copper(I) Methyltrialkylborates with Allylic Halides or 2-Propynylic Halides
Authors: Miyaura Norio , Itoh Mitsuomi , Suzuki Akira
Published: July 2006

The reactions between copper(I) methyltrialkylborates (readily obtainable from organoboranes) and allylic halides or 2-propynylic halides were found to give corresponding alkylation products. These reactions provide novel synthetic routes to 1-alkenes or 1,2-alkadienes from organoboranes.
Synthesis of 4′-Vinylbenzo-15-crown-5 from Benzo-15-crown-5
Authors: Kikukawa Kiyoshi , Nagira Kazuhiko , Matsuda Tsutomu
Published: July 2006

4′-Vinylbenzo-15-crown-5 was conveniently synthesized in 30% yield by the reaction of diazotized 4′-aminobenzo-15-crown-5 with ethylene (6–10 kg/cm2) in the presence of zerovalent palladium at room temperature.
Electronic Structures and Spectra of the Keto and Enol Forms of Acetylacetone
Authors: Nakanishi Hiroshi , Morita Hiroshi , Nagakura Saburo
Published: July 2006

Near and vacuum UV absorption spectra of acetylacetone were measured in the vapor phase and in several organic solvents at various temperatures. From the temperature dependence of the spectra, the equilibrium constant and enthalpy change between the keto and enol forms of acetylacetone were determined to be 25 at 20 °C and −4.3 kcal/mol, respectively, in the vapor phase. Rydberg excitation bands were observed at 47170 and 53300 cm−1 for the enol form, and ≈52000 cm−1 for the keto form. The estimated values of the quantum defect indicate that the Rydberg orbitals are 3s and 3p. A modified CNDO-CI method was applied to the valence-shell transitions. A weak band observed at ≈34000 cm−1 for the keto form was assigned to the first n-π* transition, and relatively strong bands observed at 38020 and 56800 cm−1 for the enol form, to the first and second π-π* transitions, respectively. Special attention was paid to the charge-transfer (CT) character pertinent to the intramolecular hydrogen bond in the excited states of the enol form. Configuration analysis of the wave functions revealed us that the first π-π* band observed at 38020 cm−1 has the CT character.
Transition-metal Complexes of Pyrrole Pigments. XIV. An Electron Spin Resonance Study of Bis(3,3′,5,5′-tetramethyldipyrromethenato)manganese(II)
Authors: Matsuda Yoshihisa , Murakami Yukito
Published: July 2006

Bis(3,3′,5,5′-tetramethyldipyrromethenato)manganese(II) in single crystalline and powdered sample states was investigated by means of K-band ESR spectroscopy. The spectral shape for the single crystal depends highly on the angle between the external magnetic field and the crystal axes. Anisotropic parameters D and E evaluated by the simulation method are 0.12±0.01 and 0.032±0.004 cm−1, respectively. These values are considerably larger than those expected for the distorted tetrahedral manganese(II) complexes formed with four equivalent donor atoms. An origin of these large anisotropic parameters has been discussed.
Preparation and Resolution of a Complete Series of [Co(en)x(tn)y(tmd)z]3+ Complexes
Authors: Kojima Masaaki , Yamada Hiroyuki , Ogino Hiroshi , Fujita Junnosuke
Published: July 2006

A complete series often complexes, [Co(en)x(tn)y(tmd)z]3+ (en=ethylenediamine; tn=trimethylenediamine; tmd=tetramethylenediamine) was obtained by preparing four new complexes, [Co(en)(tmd)2]3+, [Co(tn)2(tmd)]3+, [Co(tn) (tmd)2]3+, and [Go(en) (tn) (tmd)]3+. The new complexes were resolved into optical isomers by SP-Sephadex column chromatography. The absorption and circular dichroism spectra of all the complexes were recorded and discussed.
5-Fluorouracil Derivatives. I. The Synthesis of 1-Carbamoyl-5-fluorouracils
Authors: Ozaki Shoichiro , Ike Yoshimasa , Mizuno Haruo , Ishikawa Katsutoshi , Mori Haruki
Published: July 2006

The toxicity and tumor affinity of 5-fluorouracil (1) have been modified by the introduction of a carbamoyl group. Carbamoylation by three general methods were studied extensively: (i) The reaction of 1 with isocyanate, (ii) the reaction of 1-chloroformyl-5-fluorouracil with amine, and (iii) the reaction of 1 with carbamoyl chloride. These three methods usually give 1 -carbamoyl-5-fluorouracils (2). 3-Carbamoyl-5-fluorouracils were not obtained by any method. The 2 substances take a hydrogen-bonded structure in chloroform, a non hydrogen-bonded structure in DMSO at 80 °C, and mixed structures in DMSO at 25 °C. Thirty-six homologues shown by 2 were prepared all of these compounds showed antitumor activity. Of them, 1-hexylcarbamoyl-5-fluorouracil (HCFU) appeared to be the most promising antitumor agent when administered orally in that HCFU retains well balanced lipo- and hydro-philicity, is stable in acid in the stomach, and moreover, decomposed moderately in a tumor. Isocyanate was obtained from the reaction of amine with trichloromethyl chloroformate (TCF) by simply heating these two reagents in toluene; this offers a convenient new method for synthesizing isocyanate from amine. Several new isocyanate were obtained from amino acids.
Indirect Chemiluminescence from the Air Oxidation of Ketones and Carboxylic Acids in Alkaline Aprotic Solvents Containing 9,10-Diphenylanthracene and 9,10-Dibromoanthracene
Authors: Kamiya Isao , Sugimoto Takashi
Published: July 2006

A number of ketones and carboxylic acids have been examined for direct and indirect chemiluminescence with 9,10-diphenylanthracene and 9,10-dibromoanthracene by air oxidation. From the finding that the efficiency of the chemiluminescence was dramatically influenced by the class of the C–H bond adjacent to the carbonyl group, it was concluded that the molecules with a –COCH– group surely give an excited product during air oxidation in alkaline aprotic solvents. The reaction scheme was consistent with the evidence that most simple carboxylic acids exhibited no chemiluminescence, probably because the C–H bond adjacent to the carboxyl group is no more acidic, but keto acids exhibited emission. In several compounds, however, the chemiluminescent reaction was retarded by other functional groups.
The Formation and Structure of Bi1.34CrNbO6
Authors: Torii Yasuyoshi , Hasegawa Kanemitsu
Published: July 2006

A new ternary oxide Bi1.34CrNbO6 was prepared and characterized. The unit cell is face-centered cubic with a=10.455 Å. The structure is assumed to be of the pyrochlore type based on the space group Fd3m and was refined by trial and error to a reliability factor R of 0.0564. This pyrochlore phase was confirmed to have vacancies at the A sites and also at the special oxygen sites, and may be considered to be a rare case in this respect. The Cr3+ and Nb5+ ions are bonded octahedrally to six oxygen atoms at 2.03 Å, while the Bi3+ ions are bonded to six oxygen atoms at 2.56 Å. The structure consists of bismuth tetrahedra, the centers of which are vacant. The highly polarizable Bi3+ ion plays an important role in the formation of the defect pyrochlore structure. Related pyrochlores were also prepared.
Stereochemistry of Cobalt(III) Complexes with Thioethers. II. Geometrical Isomers, Absorption, and Circular Dichroism Spectra of Bis(terdentate-N,S,O) Complexes
Authors: Yamanari Kazuaki , Hidaka Jinsai , Shimura Yoichi
Published: July 2006

Two cobalt(III) complexes containing terdentate thioethers, bis[(2-aminoethylthio)acetato]cobalt(III)(1+), and bis[3-(2-aminoethylthio)propionato]cobalt(III)(1+) were prepared and separated into five and six geometrical isomers, respectively, by ion-exchange column chromatography. The isomers were identified on the basis of their electronic absorption and NMR spectra. The circular dichroism spectra of optically resolved isomers were measured and discussed in relation to the absolute configurations.
Syntheses of d-Arabinofuranosyl and 2′-Deoxy-d-ribofuranosyl 1,2,3-Triazolecarboxamides
Authors: Makabe Osamu , Suzuki Hiroshi , Umezawa Sumio
Published: July 2006

Several d-arabino- and 2′-deoxy-d-ribonucleosides of 1,2,3-triazolecarboxamides were synthesized by two methods, one involving acid-catalyzed fusion reactions of 1-O-acetyl derivatives (3, 5) of the corresponding sugars and 1,2,3-triazole-4-carboxylate (1), and the other by glycosylation of the trimethylsilyl derivative (2) of 1 with glycosyl halides (4, 6). Evidence for the N-glycosylation sites and anomeric configurations of the resulting nucleosides is presented.
Metal-catalyzed Organic Photoreactions. Photoreactions of Compounds Containing a Carbon-oxygen or Carbon-nitrogen Multiple Bond with Alcohols in the Presence of Titanium(IV) Chloride or Uranyl Chloride
Authors: Sato Tadashi , Yoshiie Shigeo , Imamura Takashi , Hasegawa Kazumi , Miyahara Masayuki , Yamamura Shigeo , Ito Osamu
Published: July 2006

α,β-Unsaturated carbonyl compounds and esters, cyclopropyl ketones, β-diketones, Schiff’s bases, and nitriles were irradiated in several alcohols in the presence of titanium(IV) chloride or uranyl chloride. In the titanium(IV) chloride-catalyzed reactions, the α-carbon atom of the primary alcohols underwent a bond formation, generally with the C=X (or C≡N) carbon atom of the substrates, while the bond formation occurred on a C=C carbon atom of the substrates in the uranyl chloride-catalyzed reactions. The reactions were examined under several conditions, and a possible scheme for the reactions was suggested.
Studies on the Nitration of m-Cresol. A New Selective Method for the Preparation of 3-Methyl-6-nitrophenol
Authors: Sasaki Mitsuru , Nodera Katsuji , Mukai Kunio , Yoshioka Hirosuke
Published: July 2006

A new selective method for the nitration of m-cresol has been established. 3-Methyl-6-nitrophenol was most efficiently prepared by nitration of 3-methyl-4-sulfophenyl carbonate or phosphate and subsequent hydrolysis and desulfonation. Steric effects on the attacks of sulfonium or nitronium ion to the phosphate are discussed.
Efficient Methods for Oxidation of Alcohols
Authors: Narasaka Koichi , Morikawa Anri , Saigo Kazuhiko , Mukaiyama Teruaki
Published: July 2006

Treatment of alkoxymagnesium bromides, prepared in situ from alcohols and Grignard reagent, with N-chlorosuccinimide, m-chloroperbenzoic acid, or (diacetoxyiodo)benzene in the presence of t-butoxymagnesium bromide afforded the corresponding carbonyl compounds in good yields. A wide variety of alcohols, after being converted into their bromomagnesium salts by treatment with propylmagnesium bromide, were also selectively oxidized with 1,1′-(azodicarbonyl)dipiperidine to afford the corresponding ketones or aldehydes in excellent yields.
The Thallium(I) Salt-catalyzed Formation of Isothiocyanates from Isocyanides and Disulfides
Authors: Tanaka Sakuya , Uemura Sakae , Okano Masaya
Published: July 2006

The reactions of various isocyanides with diacyl disulfides or tetraethylthiuram disulfide occur smoothly in the presence of thallium(I) acetate and thiocarboxylates in various organic solvents to give the corresponding isothiocyanates in good yields. Lead(II) acetate has an activity almost identical with that of thallium(I), while cadmium(II) and silver(I) acetates and copper(I) oxide show a slightly lower activity than the above thallium and lead salts. An ionic scheme involving a complex formation between the metal salt and one S atom of the disulfide, followed by a nucleophilic attack of isocyanide on the adjacent S atom, is proposed for this reaction. It is revealed that the reaction of isocyanide with one equivalent of thallium(III) thiobenzoate in refluxing chloroform similarly affords a good yield of the isothiocyanate through the above mechanism after the decomposition of the thallium(III) salt to thallium(I) thiobenzoate and dibenzoyl disulfide, rather than through a pathway involving thiothallation (α-addition).
The Studies of the Activated Compound. III. A Synthesis of Muscalure: (Z)-9-Tricosene
Authors: Abe Kyo , Yamasaki Tomio , Nakamura Nobuo , Sakan Takeo
Published: July 2006

A synthesis of muscalure, (Z)-9-tricosene, was carried out as an application of metal-induced acylation.
Synthesis of a Peptide Lactone, N-(3-Hydroxypicolinyl)-threonyl-d-leucyl-prolylsarcosyl-leucyl-alanyl-alanine Threonine Lactone
Authors: Kinoshita Hideki , Kotake Hiroshi
Published: July 2006

The synthesis of a peptide lactone, N-(3-hydroxypicolinyl)-threonyl-d-leucyl-prolylsarcosyl-leucyl-alanyl-alanine Threonine Lactone (21) is described. The t-butoxycarbonyl group of t-butyl O-(t-butoxycarbonyl-alanyl)-N-benzyloxycarbonyl-threonyl-d-leucyl-prolylsarcosinate (12) was deblocked selectively with formic acid in good yield. The coupling of 12 with the azide derived from t-butoxycarbonyl-leucyl-alanine hydrazide (15) with isopentyl nitrite gave a heptapeptide ester 17. Deblocking, cyclization, and hydrogenation gave a heptapeptide lactone 20 which was coupled with 3-hydroxypicolinic acid yielding 21.
Carbon-13 NMR Spectra of Methyl-1,3-dioxolanes
Authors: Senda Yasuhisa , Ishiyama Jun-ichi , Imaizumi Shin
Published: July 2006

The 13C NMR spectra of thirteen methyl substituted 1,3-dioxolanes were measured. The carbon chemical shifts of the methyl groups imply that the 1,3-transannular nonbonded interaction of the methyl groups is negligible, except in the cases of 2,2,4-trimethyl- and 2,2,4,5-tetramethyl-1,3-dioxolanes.
Cyclopropanes from Allylic Halides. I. Synthesis of Dimethyl 3-(2-Methyl-1-propenyl)-2,2-dimethylcyclopropane-1,1-dicarboxylate and Pyrocin as Precursors of Chrysanthemic Acid
Authors: Torii Sigeru , Tanaka Hideo , Nagai Yosio
Published: July 2006

Dimethyl 3-(2-methyl-1-propenyl)-2,2-dimethyl-cyclopropane-1,1-dicarboxylate and pyrocin as precursors of chrysanthemic acid were synthesized by the reaction of (2-halo-2-methylpropylidene)malonate with 2-methyl-1-propenylmagnesium bromide.
Reactions of Benzyne with Substituted Benzenes
Authors: Tabushi Iwao , Yamada Hidenori , Yoshida Zenichi , Oda Ryohei
Published: July 2006

The reactions of benzyne with substituted benzenes (anisole, chlorobenzene, methyl benzoate, benzylidyne trifluoride and toluene) giving the Diels-Alder adducts were investigated, where two positionally isomeric adducts were possible, i.e., a geminal-para adduct (1,4-adduct with respect to the substituent) and an ortho-meta adduct (2,5-adduct). From the competition reactions, relative reactivities of benzyne to substituted benzenes were estimated for the 1,4-addition and 2,5-addition. Markedly different substituent effects were observed. For the 1,4-addition, large negative ρ value (−1.79) was observed, but for the 2,5-addition, substituent effect was small. From benzyne and toluene, o-benzylbiphenyl (13) and 2-benzyl-3-phenylbenzo[5,6]bicyclo[2.2.2]octatriene (14) were obtained as the successive “ene” products together with the normal Diels-Alder adducts.
Violet Emission Spectra of CN(B2Σ) Produced in the Photodissociation of HCN and DCN
Authors: Tatematsu Setsuko , Kuchitsu Kozo
Published: July 2006

Emission spectra of the CN violet band system (B2Σ-X2Σ, Δυ=0) produced in the photodissociation of HCN and DCN by Lyman-α radiation (121.6 nm) were observed with resolution of about 0.2 nm and with sample pressures of 0.01–1.5 Torr. The spectral features of the two were similar, but the main peaks (υ′=0–4) from DCN appeared more sharply than the corresponding peaks from HCN. The relative vibrational populations and the effective rotational temperatures were estimated by a band-envelope analysis. No indication of vibrational population inversion was observed. The CN(B2Σ) radical produced from DCN is likely to have slightly higher vibrational (0.31±0.08 eV) measured from the zero-point energy) and rotational energies (0.15±0.02 eV) than that from HCN (0.23±0.08 and 0.11±0.02 eV, respectively).
Processes in the Reaction of Y2O3 with WO3
Authors: Kuribayashi Kiyoshi , Sata Toshiyuki
Published: July 2006

The processes of the solid state reaction of Y2O3 with WO3 were studied for samples mixed in the molar ratios of Y2O3 : WO3=1 : 3, 1 : 1, 7 : 4, 5 : 2, and 3 : 1. It was found that all the reactions except Y2O3 : WO3= 5 : 2 from the powders of both Y2O3 and WO3 in air proceeded according to the following order step reactions: Y2O3·3WO3→Y2O3·WO3→7Y2O3·4WO3→5Y2O3·2WO3 and 5Y2O3·2WO3→3Y2O3·WO3, with temperatures rising from 600 to 1300 °C and with an unknown compound, X, always first formed below 700 °C. In a reaction couple in contact with both Y2O3 and WO3 pellets, WO3 components preferentially diffused to the Y2O3 side to form Y2O3·3WO3 (orthorhombic form) on the boundary between them at 1000 °C.
Ion-Pair Effect on the Rate of the Base Hydrolysis of the Pentaamminechlorocobalt(III) Complex
Authors: Iida Masayasu , Yamatera Hideo
Published: July 2006

The rate of the base hydrolysis of pentaamminechlorocobalt(III) ions was measured in the presence of multivalent anions at a constant ionic strength. The results were analyzed in view of the SN1 C.B. mechanism considering the formation of ion-pairs. The ion-pairing has the effect of suppressing the acid dissociation of the complex or the formation of its conjugate base, which acts as the intermediate of the reaction. This effect out-weighs the adverse effect of the probable acceleration of the rate-determining step of the base hydrolysis. The association constants obtained for [CoCl(NH3)5]2+·SO42− and [CoCl(NH3)5]2+·P3O93− were 40±5, and 82±5, respectively (I=0.1, 25°C).
The Sensitized Photooxygenation of 2-Vinylbenzofurans
Authors: Matsumoto Masakatsu , Dobashi Satoshi , Kondo Kiyosi
Published: July 2006

The sensitized photooxygenation of benzofuran, 2-methylbenzofuran, and six 2-vinylbenzofurans was investigated. Benzofuran and 2-methylbenzofuran were stable toward singlet oxygen. On the other hand, the vinylbenzofurans were easily photooxygenated to give the 1,4-endoperoxides. The 1,4-cycloaddition of singlet oxygen to the 2-benzofurans was confirmed to proceed with stereospecificity.
Photo-acylamination on Anthracene with Use of Acyl Azides
Authors: Ichimura Kunihiro
Published: July 2006

Irradiation of anthracene in the presence of acyl azide gives isocyanate and 9-acylaminoanthracene. The photolysis of aromatic hydrocarbon-acyl azide was followed by UV spectrophotometry and analyzed by the EDQ (quotients of extinction differences) diagram method.
The Aromatic Thiocyanation of 1-Alkoxynaphthalene by the Copper(II) Thiocyanate Method
Authors: Fujiki Kiyoko
Published: July 2006

A facile thiocyanation of 1-alkoxynaphthalene using copper(II) thiocyanate afforded 4-thiocyanato compound. The reaction proceeded at a moderate temperature (80–90 °C) even for 1-alkoxynaphthalene with higher alkyl groups (C6, C8, and C12).
Quantitative Analysis of Polybutadiene by Means of Pulse FT Carbon-13 NMR
Authors: Shibata Chizuko , Yamazaki Mitsuru , Takeuchi Tsugio
Published: July 2006

13C NMR was applied to the determination of the vinyl content in polybutadiene by means of the internal standard method. Under optimum experimental conditions, it was found that 13C NMR is applicable to the quantitative analysis of polymer by use of acetonitrile as an internal standard.
Conformational Study of Glutathione by NMR
Authors: Fujiwara Shizuo , Formicka-Kozlowska Grazyna , Kozlowski Henryk
Published: July 2006

Proton NMR spectra of glutathione have been analyzed over the whole pH region. The spectra of the glutamic acid residue are of the ABCDX type at pHs below 2.5, of the AA′BB′X types in the pH region 2.5–9, and of the ABCC′X type at pHs higher than 9. For the cysteine part, spectra of the ABC type have been observed at pHs higher than 8, which change to spectra of the A2B type at pHs lower than 7. On the basis of these results the conformation of the glutathione molecule in solution has been discussed in detail.
The Crystal and Molecular Structure of Dimethyl m-Phenylenediacrylate
Authors: Nakanishi Hachiro , Sasada Yoshio
Published: July 2006

Photooligomerizable crystals of dimethyl m-phenylenediacrylate are orthorhombic, Pmn21, with a=26.419(8), b=3.960(1), c=5.935(2) Å, and Z=2. The structure was solved by the direct method and refined by the block-diagonal least-squares calculation to the R value of 0.042 for 617 observed reflections. The molecule is nearly planar and V-shaped with a mirror symmetry. A parallel plane-to-plane stack is found along the short b-axis. The molecules in the stack overlap completely, in contrast with the half-molecule overlap in the photopolymerizable crystals of this kind. The length of the b-axis is just the shortest intermolecular distance between reactive double bonds, indicating that the double bonds related by the b-translation would react to form a cyclobutane ring with a mirror symmetry.
Nucleophilic Behavior of the Phenyl Radical in the Hydrogen Abstraction Reaction from Substituted Toluenes, A Contribution to the Study of the Phenyldiazenyl Radical
Authors: Suehiro Tadashi , Suzuki Akira , Tsuchida Yasuyoshi , Yamazaki Junji
Published: July 2006

Phenyl radicals derived from benzoyl peroxide (BPO) showed nucleophilic behavior, rho=+0.18 (metaseries) for the hydrogen abstraction reaction from substituted toluenes at 80 °C, and a kinetic deuterium isotope effect, kH⁄kD=3.73±0.2, was found for toluene. Comparison of these results with those for the phenyl radicals from phenylazotriphenylmethane (PAT) leads to the suggestion that the phenyldiazenyl radicals derived from PAT abstract hydrogen from toluene to yield benzene, which should amount to about 50% of the total benzene formed.
The Mechanism of NAD(P)H Reduction Reactions
Authors: Inagaki Satoshi , Hirabayashi Yoshio
Published: July 2006

The mechanism of reduction reactions by 1,4-dihydronicotinamides is investigated from the theoretical point of view of the electron configuration and orbital interactions for many systems. The following conclusions are drawn: (1) The reactions are situated near the one-electron-transfer region in the mechanistic spectra dependent on the donor-acceptor property of the reactants; (2) the hydride-equivalent transfers involved, whether concerted or not, proceed more or less in accordance with the nature of the sequential electron-proton-electron shift rather than via direct hydride-ion transfer; (3) the paradoxical frontier orbital interaction between the σ-LUMO of C4-H of 1,4-dihydronicotinamides and the LUMO of substrates is significantly involved in the transfer of the protonic entity. Pseudoexcitation is classified into Type I, where the normal HOMO-LUMO interaction remains important in addition to the LUMO-LUMO and HOMO-HOMO interactions, and Type II, where the HOMO-LUMO interaction contributes little. The NAD(P)H reduction reactions are predicted to belong to Type II.
The Hydrocracking of a Heavy Anthracene Oil over Molten Salt Catalysts
Authors: Nakatsuji Yohji , Fujioka Shigeyuki , Nomura Masakatsu , Kikkawa Sh\={o}ichi
Published: July 2006

The hydrocracking of a heavy anthracene oil over molten salt catalysts (zinc chloride or a binary mixture of zinc chloride and another metal chloride) at 400 °C for 3 h in a batch autoclave system was carried out, and the products were mainly identified by means of GC-MS. The effects of the hydrogen pressure (60 or 100 kg/cm2), the quantity of the catalyst, and the addition of metal chloride (potassium chloride or copper(I) chloride) to zinc chloride on the product distribution were examined and discussed. Based on the detailed product analysis, it was found that cata-condensed polycyclic aromatic compounds were hydrocracked more efficiently than peri-condensed polycyclic aromatic compounds. The CuCl/ZnCl2 molten salt displayed an excellent catalytic activity for the hydrocracking of the heavy anthracene oil.
The Photochemical Synthesis of 2-Chloro-3-(2-furyl)-1,4-naphthoquinones
Authors: Maruyama Kazuhiro , Otsuki Tetsuo
Published: July 2006

Upon the irradiation of a benzene solution of 2,3-dichloro-1,4-naphthoquinone, 1, and furan derivatives, 2, 2-chloro-3-(2-furyl)-1,4-naphthoquinones, 3, were obtained, accompanyed by a liberation of hydrogen chloride. The formation of a CT-complex between 1 and 2 was essential for the progress of the reaction. The 1H-CIDNP signals which were observed during irradiation suggest an intervention of a radical pair in the reaction.
Vibrational Spectra of Ethyleneurea and Its C,C′- and N,N′-Deuterated Derivatives
Authors: Saito Yutaka , Machida Katsunosuke
Published: July 2006

Infrared and Raman spectra of ethyleneurea and its C,C′- and N,N′-deuterated compounds have been measured. The fundamental frequencies have been assigned by referring to isotopic frequency shifts and Raman depolarization ratios. A normal coordinate analysis has been carried out for the infrared active vibrations of a planar C2V molecular model. A Urey-Bradley potential function supplemented by valence type constants for the outof-plane deformation and the torsional coordinates has been used. The calculated frequencies based on a refined set of force constants agree well with the observed.
Vibration Spectra and Rotational Isomerism of Chain Molecules. IV. Diethyl Sulfide, Ethyl Propyl Sulfide, and Butyl Methyl Sulfide
Authors: Ohta Masahiro , Ogawa Yoshiki , Matsuura Hiroatsu , Harada Issei , Shimanouchi Takehiko
Published: July 2006

The Raman and infrared spectra of diethyl sulfide, ethyl propyl sulfide and butyl methyl sulfide were measured for the gaseous, liquid, glassy and crystalline states. The normal vibration frequencies were calculated, a consistent set of force constants explaining the frequencies of basic aliphatic sulfides being assumed. The rotational isomerism was studied and the following conclusions were obtained. (1) Only the all-trans form exists in the crystalline state. (2) Many forms coexist in the liquid state and most of them persist in the glassy state even at the liquid nitrogen temperature. (3) In the liquid state, the gauche conformation about the S–C axis is more stable than the trans conformation, and the gauche conformation about the C–C axis directly adjoining the S–C axis is as stable as the trans conformation. These results confirm that the repulsive force between nonbonded hydrogen atoms is one of the important factors influencing the stability of molecualr conformations. The stable conformations of the sulfide molecules were correlated with those of polythioether chains.
The Backbone Rearrangement of 3β,4β-Epoxyfriedelane and the Synthesis of Dendropanoxide
Authors: Tori Motoo , Torii Takahiro , Tachibana Kazuo , Yamada Sachiko , Tsuyuki Takahiko , Takahashi Takeyoshi
Published: July 2006

Dendropanoxide (1) was synthesized by the reaction of 3β,4β-epoxyfriedelane (19) with boron trifluoride etherate in ether at −10 °C. In the rearrangement reaction, 4α-fluorofriedelan-3β-ol (20), D : B-friedo-olean-5(10)-en-3β-ol (21), β-amyrin (22), and D : B-friedo-olean-5-en-3β-ol (23) were also produced.
The Detemination of the Formation Constants of the Triiodide Ion in Water–Alcohol Mixed Solvents at Various Temperatures
Authors: Hayakawa Katumitu , Nakamura Sumio
Published: July 2006

The formation constants of the triiodide ion were determined in water-alcohol mixed solvents by a spectro-photometric method at various temperatures. The formation reaction of the triiodide ion from an iodide ion and an iodine molecule is accompanied by a negative enthalpy change and a positive entropy change at various alcohol contents: ΔH°/kJ mol−1, −15.4 (in water) to −14.3 (in methanol) in the water–methanol system, −15.4 (in water) to −21.4 (in ethanol) in the water–ethanol system; ΔSx°/J K−1 mol−1, 36 (in water) to 57 (in methanol) in the water–methanol system, and about 36 at various ethanol contents in the water-ethanol system. The enthalpy term is the dominant factor in the water–ethanol mixtures, whereas the entropy term is the dominant factor in the water–methanol mixtures. In order to explain the thermodynamic behavior, the changes in the solvation properties as well as the activity coefficients of solutes must be considered in both the mixture systems.
Infrared Studies on Water Adsorption Systems with the Use of HDO. I. Molecular Sieves 13X and 4A
Authors: Hino Masao
Published: July 2006

It was shown that the use of HDO molecules in IR studies on water adsorption system is advantageous for obtaining information as to whether 1) a band arises from the surface structural hydroxyl groups or from adsorbed water molecules, 2) a band arises from an overtone bending vibration, and 3) water molecules are adsorbed in a state of its two hydroxyl bonds being equivalent. The bands in the spectra of Molecular sieves–H2O systems were assigned as follows. I) 13X–H2O system. Bands at 3752, 3685, and 3647 cm−1 correspond to surface structural OH, bands at 3697, 3360, and 1650 cm−1 to asymmetrically adsorbed water molecules, band at 3230 cm−1 to overtone bending vibration of the same molecules. The band at 3590 cm−1 was found to arise from some other type of adsorbed water molecules. II) 4A–H2O system. Bands at 3500, 3400, and 1660 cm−1 correspond to symmetrically adsorbed water molecules, band at 3280 cm−1 to overtone bending vibration of the same molecules. Another type of adsorbed water was suggested to be present.
Vibration Spectra and Rotational Isomerism of Chain Molecules. V. 2,5-Dioxahexane, 2,5-Dithiahexane, and 2-Oxa-5-thiahexane
Authors: Ogawa Yoshiki , Ohta Masahiro , Sakakibara Masaaki , Matsuura Hiroatsu , Harada Issei , Shimanouchi Takehiko
Published: July 2006

The Raman and infrared spectra of 2,5-dioxahexane CH3OCH2CH2OCH3, 2,5-dithiahexane CH3SCH2CH2SCH3 and 2-oxa-5-thiahexane CH3OCH2CH2SCH3 were measured for the gaseous, liquid, glassy and crystalline states and were correlated with the normal-vibration calculations. The rotational isomerism was studied and the following conclusions were obtained. (1) The molecular form existing in the crystalline state is a non-extended form, in contrast with the cases of the unbranched ethers or sulfides containing one oxygen or sulfur atom which take the extended all-trans form. (2) Many forms coexist in the gaseous, liquid and glassy states. (3) The form existing in the crystalline state is the most stable in the liquid state. It was found that the repulsive force between non-bonded hydrogen atoms is one of the important factors influencing the conformational stabilities and for 2,5-dioxahexane the dipole-dipole interaction is another important factor. The stable conformations of these molecules were correlated with those of the polyether and polythioether chains. The stable isomers of 2-oxa-5-thiahexane could be explained on the basis of the knowledge of the conformational stabilities of the unbranched ethers and sulfides. The force constants of the ethers and sulfides were satisfactorily transferred to 2-oxa-5-thiahexane.
The Liquid-phase Oxidation of Aldehydes with Fe,Cu-Poly-phthalocyanine and Cobalt Tetra-p-tolylporphyrin
Authors: Ohkatsu Yasukazu , Sekiguchi Osamu , Osa Tetsuo
Published: July 2006

The effect of chemical species in a reaction system on the oxidation reaction of aldehydes was studied using Fe,Cu-polyphthalocyanine and cobalt tetra-p-tolylporphyrin as catalysts. Both catalysts activated the oxygen molecule on their central metals and then abstracted the hydrogen atom from aldehydes to initiate autoxidation. In this initiation step, every chemical species present in the reaction system, such as the solvent, the aldehyde, the oxygen molecule and the catalyst, is found to have an effect, one after another, either to accelerate or to retard the rate of initiation. The correlation of the nature of chemical species with such mutual interaction was discussed in detail.
Thermochemistry of Bis(tropolonato)copper(II)
Authors: Ribeiro da Silva Manuel A V , Irving Roger J
Published: July 2006

The standard enthalpy of formation of crystalline bis(tropolonato)copper(II) has been determined at 298.15 K by solution calorimetry: ΔHf°[Cu(trop)2] (c)=−102.47±0.42 kcal mol−1. Enthalpy changes at 298.15 K for the following hypothetical gaseous reactions have been subsequently derived:

2& Cu(g)+2 trop^.(g)=[Cu(trop)_2](c) & & ΔH=-150.4±14.1 kcal mol^-1

& Cu^2+(g)+2 trop^-(g)=[Cu(trop)_2](c) & & ΔH=-731.4±11.4 kcal mol^-1

The corresponding homolytic (E) and heterolytic(E′) copper(II)-oxygen bond energy parameters were calculated as

E_Cu–o=38±4 kcal mol^-1 and E’_Cu–o=183±3 kcal mol^-1

respectively.
Flux Growth of Rare-earth Niobates with Fergusonite Structure
Authors: Sugitani Yoshinori
Published: July 2006

Single crystals of rare-earth niobates RNbO4 (R denotes a rare-earth element) were grown from a melt of PbF2–PbO flux. They are monoclinic and isostructural with natural and synthetic fergusonites. These crystals, except those containing Pr, Nd, Sm, and Ho were found to emit luminescent colors under UV irradiation.
Improved Syntheses of 3′-Deoxybutirosin A and B
Authors: Watanabe Isamu , Tsuchiya Tsutomu , Umezawa Sumio
Published: July 2006

3′-Deoxybutirosin B and A (16, 17) were synthesized via condensation of 3,2′-bis-N-benzyloxycarbonyl-4′,6′-O-cyclohexylidene-3′-deoxyparomamine 1,6-carbamate (2) with tris-O-(p-nitrobenzoyl)-d-ribofuranosyl and -d-xylofuranosyl bromide, respectively, followed by 6′-O-tosylation of the decyclohexylidene derivative (8 and 9), cyclic 1,6-carbamate opening and amidation with (S)-4-benzyloxycarbonylamino-2-hydroxybutyric acid at the free C-1 amino group.
Pure Nuclear Quadrupole Resonance of Ionic Halides. I. 79Br-NQR Investigation of the Hydrogen Bonding, the 1H-2D Isotope Effect, and the “Order-Disorder” Transition in the Anilinium Bromides C6H5NH3⊕Br\ominus, C6H5ND3⊕Br\ominus, and C6D5NH3⊕Br\ominus
Authors: Pies Wolfgang , Weiss Alarich
Published: July 2006

The 79Br-NQR spectra of anilinium bromide, C6H5NH3⊕Br\ominus, of anilinium-d3 bromide, C6H5ND3⊕Br\ominus, and of aniliniunw-d5 bromide, C6D5NH3⊕Br\ominus, have been investigated in the temperature range 77≤T⁄K≤350. The three compounds show an order-disorder phase transition near room temperature. The respective transition temperatures have been determined as 296.9 K (C6H5NH3⊕Br\ominus), 291.5 K (C6H5ND3⊕Br\ominus), and 297.6 K (C6D5-NH3⊕Br\ominus). The large value of the 79Br-NQR frequency (v=17.780 MHz at 77 K for C6H5NH3⊕Br\ominus) and the large 1H–2D isotopic shift of this frequency (≈400 kHz at 77 K by deuteration of the NH3⊕-group) have been interpreted in terms of hydrogen bonding N-H…Br\ominus. The state of order in the high temperature modification is discussed in the light of the 79Br-NQR spectrum. The 79Br-NQR frequency of the Br\ominus ion in the low temperature modification is related to the change in the monoclinic angle β and to the temperature dependence of the order parameter s∝{(Tc–T)⁄Tc}1⁄3.
Application of a Coagulated Mixture Prepared from Finely Divided Cation and Anion Exchange Resins to the Enrichment of Copper (II)
Authors: Abe Masutaro , Ohzeki Kunio , Kambara Tomihito
Published: July 2006

Mutual coagulation takes place, when a suspension of finely divided cation exchanger is added to that of anion exchanger. The resulting mixed resin is bulky and easily separated from the solution by filtration. A rapid and selective collection of a trace amount of copper(II) ion was carried out by the combined use of mixed resin and 8-quinolinol-5-sulfonic acid (H2qs). The copper(II) collected on the mixed resin in the form of [Cu(qs)2]2− was brought into solution from the resin with ethylenediaminetetraacetate, converted into copper(II)–diethyldithiocarbamate, extracted into methyl isobutyl ketone, and determined by atomic absorption spectrometry. The method was satisfactorily applied to the determination of a trace amount of copper(II) in well water.
The Electronic Structure and Homolytic Dissociation of Dibenzoyl Peroxide
Authors: Kikuchi Osamu , Hiyama Akihisa , Yoshida Hiroshi , Suzuki Keizo
Published: July 2006

The conformations and electronic structures of dibenzoyl peroxide (BPO) and the benzoyloxyl radical (PhCOO) were elucidated by means of closed-shell and restricted open-shell SCF MINDO/3 calculations. The dihedral angle of BPO between the two PhCOO planes was predicted to be 115°, and the barrier to the trans form of BPO was estimated to be very small. The ground state of the PhCOO radical was predicted to be of the ∑-type. The non-planar conformation of PhCOO was more stable (2 kcal/mol) than the planar one. The variation in the radical-pair property of the lowest state of acetyl peroxide during the homolytic dissociation process was estimated by the analysis of the two-configuration wavefunctions. The substituent effect on the rate of the homolytic dissociation of BPO was discussed in terms of the electronic structures of substituted BPO.
Pyrolytic Sulfurization Gas Chromatography. II. Simple Determination of the Correction Factors Using Five Standard Compounds
Authors: Hara Tadashi , Fujinaga Kaoru , Tsuji Katsuya
Published: July 2006

An improvement has been made in the pyrolytic sulfurization gas chromatographic method, by which the atomic ratio between C, H, O, and N in a sample can be simultaneously determined. Analysis was carried out by use of the correction factors instead of calibration curves. Correction factors were obtained by use of five standard compounds, naphthalene, thiourea, cyanoguanidine, sucrose, and amidosulfuric acid. The method is simple, accurate, and applicable to various compounds.
Metal-Assisted Terpenoid Synthesis. V. The Catalytic Trimerization of Isoprene to trans-β-Farnesene and Its Synthetic Applications for Terpenoids
Authors: Akutagawa Susumu , Taketomi Takanao , Kumobayashi Hidenori , Takayama Kiyoshi , Someya Taichi , Otsuka Sei
Published: July 2006

Isoprene oligomerization was effected with a catalyst system Ni(OR)(η3-C3H5)PPh(NEt2)2 (R=n-C11H23, n-C15H31) to give a linear trimer fraction above 70% yield. The major component of the trimer fraction is (E)-7,11-dimethyl-3-methylene-1,6,10-dodecatriene (trans-β-farnesene) (1). The minor constituents of the fraction are (E)-2,6-dimethyl-10-methylene-1,6,11-dodecatriene. As slightly higher boiling point fractions, two cyclic trimers 1,5,9-trimethyl-1,5,9-cyclododecatriene and 1,5,10-trimethyl-1,5,9-cyclododecatriene were detected. Factors that influence the reaction path leading to 1 were discussed. Sesqui- and diterpenoids, including farnesyl acetate, farnesylacetone and isophytol were synthesised starting from 1. A regioselective tail to tail coupling of 1 was achieved with a palladium catalyst to give the dimer C30H48 which, upon catalytic hydrogenation, gave perhydrosqualene in 85% yield.
The Codimerization of Styrene and Butadiene with Three-Component Catalysts Consisting of Palladium Salt, Lewis Acid, and Tertiary Phosphine
Authors: Ito Takehiko , Takami Yasuo
Published: July 2006

The reaction of styrene and butadiene in the presence of a three-component catalyst consisting of a palladium salt, a Lewis acid, and a tertiary phosphine was investigated. As the three-component catalyst, combinations of such palladium(II) salts as (π-C3H5PdCl)2, (PdCl2·C6H5CH=CH2)2 and Pd(acac)2, such Lewis acids as BF3 and AlCl3, and such tertiary phosphines as Ph3P and Bu3P were adopted. From the reaction, 1-phenyl-1,4-hexadiene (a straight-chain codimer) was obtained as the main product, together with small amounts of branched-chain codimers. The ratio of the 1-phenyl-1,4-hexadiene to the branched-chain codimers was varied to some extent by changing the molar ratio of styrene to butadiene. With an increase in the molar ratio the ratio of 1-phenyl-1,4-hexadiene to the branched-chain codimers decreased. A reaction mechanism for the selective formation of 1-phenyl-1,4-hexadiene which involves the addition of butadiene, in preference to styrene, to a palladium hydride is proposed.