bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereochemistry of Cobalt(III) Complexes with Thioethers. III. Vicinal Circular Dichroism due to the Chiral Sulfur Donor Atom
Authors: Yamanari Kazuaki , Hidaka Jinsai , Shimura Yoichi 
Published: July 2006

Abstract
Two kinds of mixed type cobalt(III) complexes, [(2-aminoethylthio)acetato](l-methioninato)cobalt(III) chloride and [3-(2-aminoethylthio)propionato](l-methioninato)cobalt(III) chloride, have been prepared and chromatographically separated into seven and eight isomers, respectively. The characterization of isomers based on their electronic absorption and 1H NMR spectra leads to the conclusion that there have been obtained four pairs of diastereomers due to the sulfur chirality of the coordinated l-methioninate. The circular dichroism spectra of isomers have been measured and discussed in relation to the absolute configurations. The vicinal CD contribution due to the chiral sulfur atom of l-methioninate has been estimated by applying an additivity rule for the three diastereomeric pairs.
ESR Study of the t-Pentyl Derivative of Yang’s Biradical
Authors: Mukai Kazuo , Yorimitsu Koichi , Mishina Tadashi 
Published: July 2006

Abstract
An asymmetrical t-pentyl derivative of Yang’s biradical was prepared, and the g- and D-tensor values of the biradical were determined from an analysis of an asymmetric ESR spectrum of a frozen solution containing the biradical. The result may be understood by assuming that the benzene ring onto which two pentyl groups are substituted is twisted more than the other two benzene rings. On the other hand, the fluid solution ESR spectrum shows seven hyperfine splittings due to six equivalent meta ring protons in the three benzene rings of the pentyl derivative.
Low-spin Cobalt(II) Complexes with 6,13-Diaryl-1,8-dihydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecene
Authors: Nishida Yuzo , Sumita Akira , Kida Sigeo 
Published: July 2006

Abstract
The ESR spectra of the title compounds were measured at 77 K. From the results, it was concluded that an unpaired electron is localized in the dyz orbital of the cobalt atom of the complexes.
Photochromism of 2,2,4,6-Tetraphenyl-1,2-dihydro-1,3,5-triazine
Authors: Hayashi Taro 
Published: July 2006

Abstract
2,2,4,6-Tetraphenyl-1,2-dihydro-1,3,5-tri-azine shows temperature dependent photochromism only in a solid state at temperatures above ca. −70 °C under UV(320–380 nm) irradiation, giving several absorption maxima in the visible region, but no change in the IR spectrum. N-Substituted derivatives show no photochromism.
Reaction of Dioxygen Complexes with Catechols
Authors: Muto Shigeaki , Tasaka Kazuaki , Kamiya Yoshio 
Published: July 2006

Abstract
The square planar dioxygen complexes MO2(PPh3)2(M=Pt, Pd) reacted with catechols at low temperature to give H2O2 and the corresponding catecholato complexes, characterized by their physical properties, in high yields. A similar treatment of PtO2(PPh3)2 with o-substituted anilines afforded the corresponding adducts and H2O2 in moderate yields.
Friedel-Crafts Reaction of Benzene with 2-Phenylbutanedioic Anhydride
Authors: Hashimoto Iwao , Takatsuka Ryozo 
Published: July 2006

Abstract
The AlCl3-catalyzed acylation of benzene with 2-phenylbutanedioic anhydride was found to give a mixture of 3-benzoyl-2-phenylpropanoic acid, isomeric 3-benzoyl-3-pehnylpropanoic acid, and 3-oxoindan-1-carboxylic acid. The distribution of the products was affected markedly by the amount of AlCl3 or solvents used.
An Efficient Synthesis of Bicyclo[3.1.0]hex-3-en-2-one
Authors: Oda Masaji , Kanao Yoshinori , Kasai Masaji , Kitahara Yoshio 
Published: July 2006

Abstract
Bicyclo[3.1.0]hex-3-en-2-one is synthesized in fair yield in five steps from 4-cyclopentene-1,3-dionefuran Diels-Alder adduct.
The Structure of Sendanolactone, a New Triterpenoid from Melia azedarach L. var. japonica Makino
Authors: Ochi Masamitsu , Kotsuki Hiyoshizo , Tokoroyama Takashi , Kubota Takashi 
Published: July 2006

Abstract
Sendanolactone, a new tetracyclic triterpenoid from the bark of M. azedarach L. var. japonica Makino, was determined as 3,6-dioxo-13α,14β,17α-lanosta-7,24-dien21,16β-olide on the basis of chemical and spectroscopic evidence.
A Convenient and General Preparation of Diphenyl Tellurium Dicarboxylates
Authors: Tamagaki Seizo , Hatanaka Isao , Kozuka Seizi 
Published: July 2006

Abstract
A number of diphenyl tellurium dicarboxylates were readily prepared from diphenyl telluroxide and carboxylic acids or anhydrides. Some of them were also derived through the carboxylate exchange from readily available tellurium carboxylates.
Alicyclic Terpenoids from Cyclocitryl Phenyl Sulfides. V. A Synthesis of Ferruginol
Authors: Torii Sigeru , Uneyama Kenji , Hamada Kazuhide 
Published: July 2006

Abstract
Ferruginol a precursor for taxodionesynthesis, was prepared by the coupling of C(10) units between 2-(phenylsulfonylmethyl)-1,3,3-trimethylcyclohexane and 3-isopropyl-4-methoxybenzyl bromide followed by desulfonation and acid-catalyzed cyclization.
Exciplex and EDA Complex Fluorescence in 1,4-Dicyanonaphthalene with Alkylbenzenes and Alkylnaphthalenes
Authors: Itoh Michiya , Furuya Shu-ichi , Okamoto Toshihiko 
Published: July 2006

Abstract
The exciplex (at room temperature) and EDA complex (at low temperature) fluorescence was observed in 3-methylpentane solution of 1,4-dicyanonaphthalene with several alkylbenzenes and alkylnaphthalenes. The fluorescence behavior provides evidence for an identical fluorescent state of the exciplex and EDA complex.
NMR Studies of Picolyl-type Carbanions. IV. Anions Produced by Reactions of 2-Substituted Pyridines with Butyllithium
Authors: Konishi Kazuyori , Takahashi Kensuke 
Published: July 2006

Abstract
The 13C and 1H NMR spectra of 2-pyridylmethyl (α-picolyl), 2-pyridylamino, 2-pyridyloxy, and 2-pyridylthio anions were observed in polar solvents with lithium as a counter ion. The chemical shifts are compared with the electron densities calculated using the PPP and CNDO/2 MO methods. A linear relationship was obtained between the 13C chemical shifts and π-electron densities. The charge distributions on the anions are discussed, and it is found that the 2-pyridylamino anion and its methyl derivatives can be regarded as delocalized anions with the same significance as a series of picolyl anions.
Application of Infrared ATR Spectroscopy to Liquid Crystals. I. Surface-Induced Orientation in Thin Films of Nematic MBBA
Authors: Hatta Aritada 
Published: July 2006

Abstract
Infrared dichroism of nematic liquid N-(p-methoxybenzylidene)-p-butylaniline (MBBA) was measured using a conventional transmission method and an ATR method. In the former, KBr windows were used as substrates. The degree of orientation order of the homogeneous structure, which was achieved by a rubbing procedure, was obtained to be S=0.40. Using the measured dichroic ratios, the angles between the transition moments and the long axis of the molecule were calculated. The calculated values are in satisfactory agreement with the molecular conformation already suggested. In the ATR method, In2O3-coated glass plates were used as substrates. Rubbing of the In2O3 surface gave a uniform homogeneous orientation with an S value of 0.57. An In2O3 surface treated with dimethyldichlorosilane gave a homeotropic texture with an S value of 0.53. The directions of the transition moments relative to the long axis of the molecule closely agreed with those obtained from transmission spectra.
Synthesis of Alanyl-1-aminoethanesulfonic Acid
Authors: Shiba Tetsuo , Miyoshi Kenichi , Kusumoto Shoichi 
Published: July 2006

Abstract
For the purpose of the verification of an expectation that the structural analogs of d-alanyl-d-alanine which participates in the biosynthesis of cell wall peptides might inhibit the growth of microorganisms, alanyl-1-aminoethanesulfonic acid was synthesized by the mixed anhydride method. Four diastereomers were separated and their absolute configurations were deduced on the basis of X-ray analysis. None of these dipeptide analogs and their benzyloxycarbonyl or t-butoxycarbonyl derivatives showed appreciable activity against E. coli.
The Behavior of Aqueous Solution of Sodium Deoxycholate in Capillary Flow
Authors: Sugihara Gohsuke , Tanaka Mitsuru , Matuura Ryohei 
Published: July 2006

Abstract
Primary micelles form secondary, polymer-like aggregates in a capillary flow of aqueous solution of sodium deoxycholate (SDC). The formation of the polymer-like aggregate is promoted by mechanical action, degradation being simultaneously caused by shearing stress. The viscosity of the SDC solution in the capillary flow attains equilibrium value between polymerization and degradation. The viscosity changes a great deal with the time of observation and pH. Under given conditions the SDC solution behaves as a non-Newtonian fluid obeying a power-law.
Comparison of Experimental and Calculated Oscillator Strengths for Condensed Ring Compounds
Authors: Yoshinaga Tetsutaro , Hiratsuka Hiroshi , Tanizaki Yoshie 
Published: July 2006

Abstract
The electronic absorption spectra of eighteen aromatic condensed ring compounds (C2v or D2h) were studied by means of comparison between the calculated and experimental results in terms of three fundamental factors: the electronic transition energy, the direction of the electronic transition moment, and the oscillator strength. The three experimental factors were obtained from the component spectra polarized to the long and short axes of the molecule, which were determined by means of the dichroism analysis technique. The calculated oscillator strengths were obtained by the dipole-length, dipole-velocity, and mixed-dipole methods. From the comparison between experimental and calculated results, it was found that the mixed-dipole method gives the best fit of the values to the experimental ones.
ESR Studies of the Photoreduction of Quinones. II. The Reinter-pretation of Semiquinone Intermediates from Halogenated p-Benzoquinones in Ethanol
Authors: Kambara Yoshihiko , Yoshida Hiroshi , Rånby Bengt 
Published: July 2006

Abstract
A reinterpretation was made of the electron spin resonance spectrum of semiquinone intermediates during the photolysis of a flowing solution of tetrachloro-p-benzoquinone (chloranil) in ethanol. The photoinduced spectrum with a width of 0.06 mT with an unresolved hyperfine structure was found to be identical with the spectrum of the semiquinone anion generated by reducing chloranil in an alkaline ethanol solution. This and other observations indicated that the photoinduced spectrum was due to the chloranil semiquinone anion formed primarily by the one-electron transfer to chloranil from the solvent ethanol, rather than to the semiquinone radical. The photoinduced one-electron transfer reaction was found, though qualitatively, to proceed more efficiently for chloranil and fluoranil, with a larger electron affinity, than for p-benzoquinone and dichloro-p-benzoquinones.
Molecular Structure of 2-Chloropropane, as Determined by a Combined Use of the Electron Diffraction Data and the Spectroscopic Moments of Inertia
Authors: Iijima Takao , Seki Schigenori , Kimura Masao 
Published: July 2006

Abstract
The gas-phase molecular structure of 2-chloropropane, (CH3)2CHCl, has been investigated by means of electron diffraction and by a joint analysis of the diffraction results and the spectroscopic moments of inertia. The structure parameters, distances in rg and angles in \varphiav, were determined (with parenthesized limits of error) to be as follows; C–Cl 1.812(1) Å, C–C 1.527(1) Å, C···Cl 2.720(2) Å, C–H 1.104(4) Å, ∠CCC 112.7(4)° and ∠HCH 108.5(8)°. The CCHsec angle was assumed to be 109.8(20)°. The present results, together with the data for other molecules, confirmed a systematic elongation of the C–Cl rg-distance in the series of methyl, ethyl, isopropyl, and t-butyl chlorides.
Deacylations and Syntheses of Some 9-Acylfluorenes
Authors: Kimura Takao , Minabe Masahiro , Tsubota Motohiro , Suzuki Kazuo 
Published: July 2006

Abstract
Deacylations of substituted 9-acetyl-, 9-propionyl-, 9-benzoyl-fluorene, and 9-fluorenyl 9-methyl-9-fluorenyl ketones were studied; the reactivity of deacylation was enhanced by the substitution of the 9-hydrogen atom on 9-acetylfluorene. The reaction of 9-acetylfluorene with ethyl nitrate afforded 9-aci-nitrofluorene.
A Study of the Transport of Tetraalkylammonium Ions through Ion-exchange Membranes
Authors: Inenaga Kiyotoshi , Yamauchi Akira , Kimizuka Hideo 
Published: July 2006

Abstract
The membrane potential and conductance of the cation-exchange membrane-aqueous quaternary tetraalkylammonium chloride systems have been measured by using NH4+, tetramethyl-(Me4N+), tetraethyl-(Et4N+), tetrapropyl-(Pr4N+), and tetrabutylammonium ions (Bu4N+). The potential change in the concentration cell with these salts was about 58 mV for a tenfold change of concentration. The membrane conductance in the concentration cell increased with the concentration. The membrane permeability, as estimated from the potential and conductance data, was in the order of NH4+&gt;Me4N+&gt;Et4N+&gt;Pr4N+&gt;Bu4N+; it is proportional to the geometric mean of the activities of exterior solutions. The effective pore size of the membrane was deduced from the conductance data and found to be ca. 10 Å. The selective permeation coefficient has been determined from the potential data of the two- and multi-ionic systems. The selectivity data obtained with the two-ionic system were in agreement with those obtained with the multi-ionic system. The selectivity increased with the chain length of the cation, in contrast to the reversed order of the membrane permeability in the concentration cell. This was attributed to the decreasing mobility with the increasing chain length.
Ultraviolet Spectral Study of o- and p-(Halomercurio)phenols
Authors: Yadav P L , Jha N K , Ramakrishna V 
Published: July 2006

Abstract
The ultraviolet spectra of o- and p-(halomercurio)phenols, o- and p-OHC6H4HgX(X=F, Cl, Br, or I) have been recorded in ethanolic solution and λmax and logεmax have been recorded. The spectra of these compounds have been interpreted in terms of the correlation with the spectra of benzene. HgX group is shown to be having electron-withdrawing effect on the benzene ring. Variation in the values of λmax and logεmax on changing from o- to p-derivative for a particular (halomercurio)phenol and on changing the halogen attached to mercury has been explained.
Studies on the Mechanism and Kinetics of Propylene Oligomerization and Hydrooligomerization on Zeolites
Authors: Hassan Shawky M , Panchenkov G M , Kuznetsov O I 
Published: July 2006

Abstract
The propylene conversion process has been studied in the presence of synthetic zeolites of different types and metal ions. The NiX zeolite is selective for the oligomerization of propylene. On the zeolites of different other metal ions, the hydro-oligomerization process took place. It has been found that the obtained 3-methylpentenes are primary products of the propylene oligomerization. A scheme mechanism has been proposed assuming an intermediate of a cyclobutane derivative. The mechanism explains the formation of all the obtained products of propylene conversion on the synthetic zeolites.
Multiple Relaxation Processes in Long Chain Molecules at Microwave Frequencies
Authors: Purohit H D , Sharma H S 
Published: July 2006

Abstract
The permittivity ε′ and dielectric loss ε″ of octanoyl, undecanoyl, and lauroyl chlorides have been measured in benzene for five different concentrations varying from 0.02 to 0.10 wt fraction at three different microwave frequencies, viz. 3.31, 9.83, and 26.90 GHz at 35 °C. The static permittivity ε0 at 100 kHz and the high frequency limiting permittivity ε∞ have also been measured at the same temperature. The permittivity and dielectric loss at different frequencies have been plotted against concentration and their slopes have been used to draw normalised complex plane plots between (a′–a∞)/(a0–a∞) and a″/(a0–a∞) for these compounds. Such plots show a skewed arc dielectric behaviour. The values of distribution parameter β, characteristic relaxation time τ0, average relaxation time τav, and dipole moment μ have been reported for the first time. The relaxation mechanism in these three molecules has been explained on the basis of multiple relaxation processes.
Preparation and Properties of the Uni- and Binuclear [Co(III)N2O4] Type Complexes Containing (S)-2-Amino-1-propanol
Authors: Nishide Toshikazu , Saito Kazuo 
Published: July 2006

Abstract
Reactions of (S)-2-amino-1-propanol (S-praH) with the tricarbonatocobaltate(III) solution gave binuclear complexes bridged by carbonates, or carbonate and hydroxide. The carbonate was replaced by oxalate (ox2−) to give binuclear complexes [(S-praH)2Co(ox)2Co(S-praH)2]2+ and uninuclear trans(N)cis(O)-[Co(ox)(S-pra)(S-praH)]. Another uninuclear complex [Co(ox)(S-praH)2]+ was obtained by direct synthesis from S-praH and cobalt(II) acetate by oxidation with lead dioxide. Column chromatography with SP-Sephadex C-25 was useful for separating the geometrical isomers, which were identified by PMR, IR, visible, and UV absorption spectra. Their circular dichroism (CD) spectra changed depending on pH of the aqueous solution. All the S-pra− chelates have δ-conformation, which is characterized by an intensive plus CD component in the 25000 cm−1 region, regardless of the skeletal structure of the complexes.
Synthesis of Taxodione, Royleanone, Cryptojaponol, and Methyl 11-Hydroxy-12-methoxy-7-oxoabieta-8,11)13-trien-18-oate
Authors: Matsumoto Takashi , Ohsuga Yasuo , Harada Shogo , Fukui Kenji 
Published: July 2006

Abstract
Oxidation at the C-11 position of methyl 12-hydroxyabieta-8,11,13-trien-18-oate (II) and ferruginol (XXXII) were successfully carried out using benzoyl peroxide, and the resulting phenols (VII and XXXVII) were further converted into taxodione (III), royleanone (IV), cryptojaponol (V), and methyl 11-hydroxy-12-methoxy-7-oxoabieta-8,11,13-trien-18-oate (VI).
Complex Formation of Silver(I) Ion with Some Aliphatic Diamines
Authors: Ohtaki Hitoshi , Cho Kenji 
Published: July 2006

Abstract
Complex formation of silver(I) ion with 1,3-propanediamine and 1,4-butanediamine has been studied poten-tiometrically at 25 °C in 3 mol dm−3 LiClO4 aqueous solution. Some additional experiments have been carried out in the system of silver-1,2-ethanediamine of large diamine/Ag ratios, the system having been examined in a previous work at small diamine/Ag ratios. Over the pH range of 6—10.4, the emf data obtained in the silver-diamine solutions could be explained in terms of the formation of the following complexes (L denotes the free diamine molecule): In a solution of low pH (pH=6—8), the AgHL2+ and AgH2L23+ complexes are formed. In an alkaline solution, the AgL+, Ag2L22+, and AgL2+ complexes are formed, and the relative amounts of the complexes depend on the concentrations of the metal and ligand (L) and also the ratio of these concentrations. The Ag(OH)L complex becomes a main species at the highest pH examined. In some cases the formation of the AgHL22+, Ag2HL23+, and Ag2L2+ complexes is suggested from the graphical or computer analysis of the data, but the formation constants of the complexes are rather uncertain. Over the whole pH range examined, the AgHL2+, AgH2L23+, AgL+, and Ag2L22+ complexes are predominant in all the systems.
Phthalimides. I. Base-catalyzed Lossen Rearrangement and Acid-catalyzed Beckmann Rearrangement with N-(Arylsulfonyloxy)phthalimides
Authors: Fahmy A F M , Aly N F , Nada A , Aly N Y 
Published: July 2006

Abstract
N-(Arylsulfonyloxy)phthalimides undergo base-catalyzed Lossen rearrangement with amines, and amino acids to give N,N′-diaryl ureas and amine salts. They behave similarly with phenylhydrazine in alcohol to give a mixture of N-hydroxyphthalimide and phenylhydrazine salts. However, N-(arylsulfonyloxy)phthalimides undergo isomerization followed by Beckmann rearrangement to give a mixture of 4-aryl-1H-2,3-benzoxazin-1-ones and diarylsulfones.
Thermally Dissociative Degradation of Polymers Containing Dicyclopentadiene Ring in Main Chains
Authors: Miura Masatoshi , Akutsu Fumihiko , Hirose Shigeo , Ikeno Yoshiyuki , Nagakubo Kuniharu 
Published: July 2006

Abstract
Polymers containing dicyclopentadiene units in their main chain were prepared by the polycondensation of dicyclopentadienedicarbonyl dichloride with bis(p-hydroxyphenyl) ether or 2,2-bis(p-Khydroxyphenyl)propane. Thermal analysis showed that the dicyclopentadiene units dissociate reversibly. The results of thermal degradation in a nitrobenzene solution indicate that a reversible degradation occurs at 10% concentration of the polymer, and an irreversible one at concentration below 1%. The activation energy of the dissociation of dicyclopentadiene units in the main chain of the polymer was estimated to be 30 kcal/mol.
Kinetic Study of the Reactions of Phenacyl Benzoates with Trialkyl Phosphites
Authors: Hashimoto Shizunobu , Furukawa Isao , Tatsumi Takao 
Published: July 2006

Abstract
The reactions of phenacyl benzoates, X–C6H4COCH2OCOC6H4–Y (1a–i), with trialkyl phosphites (2a–c) giving dialkyl 1-arylvinyl phosphates (3a–d) in high yields were studied kinetically using the GLC technique. The overall reactions are second order, and exhibit a moderate solvent effect and catalysis upon the addition of certain organic acids. The activation energy, Ea=16.5 kcal/mol, and entropy, ΔS\eweq=−38.5 e.u., were obtained from the reaction of 1a with 2b, and the ρ value obtained using σ for reactions of the two series of 1a with 2b was ρx=3.4 and ρY=1.0, respectively. The reactivity of 2 in this reaction is markedly increased in the order, Me&lt;Et&lt;i-Pr. These and other data accumulated support a mechanism for this reaction involving a ratedetermining addition of phosphorus atoms in 2 to the carbonyl carbon of the phenacyl group followed by rearrangement of the phosphorus moiety to the carbonyl oxygen of the phenacyl group.
Steric Effects of Alkyl Substituents on the N–H Stretching Absorptions and Rotational Isomerism of N,N′-Dialkylthioureas
Authors: Mido Yoshiyuki , Yamanaka Takashi , Awata Ryoichi 
Published: July 2006

Abstract
The fundamental N–H stretching absorptions of twenty nine N,N′-dialkylthioureas were observed in dilute solutions. The observed frequencies were classified into five groups assignable to the out, three different types of the trans, and the cis forms. The steric hindrance between the bulky t-butyl group and the thiocarbonyl sulfur, which is larger than for N,N′-dialkylureas, was suggested to cause the out form. Dialkylthioureas of RTUtB type seem to exist to a great extent in the trans-out conformation in solutions. It is suggested that it is not the N–H group with the bulky t-butyl group but the N–H group in the opposite part which is out of the skeletal plane. The energy difference between the out and the trans forms was found to be ΔH=430±100 cal mol−1.
The Glow-discharge Reactions of Pyrrole, Pyrrolidine, and Butylamine
Authors: Kikkawa Sh\={o}ichi , Nomura Masakatsu , Hosokawa Noritaka 
Published: July 2006

Abstract
The glow-discharge reactions of pyrrole, pyrrolidine, and butylamine were carried out. Pyrrolidine produces a complex mixture of products, the most prevalent of which is (Remark: Graphics omitted.) (R: H, CH3, and C2H5), and butylamine yielded primarily CH3(CH2)3N=CHR (R: CH3, C2H5, and C3H7) along with CH3(CH2)3NHCH2CN, whereas pyrrole afforded a mixture of acrylonitrile, crotononitrile, benzene, α-methylpyrrole and β-methylpyrrole, together with large amounts of HCN. The formation of characteristic products, α-(1-pyrrolidinyl) nitrile derivatives with pyrrolidine, and the yield of butylaminoacetonitrile with butylamine can be explained by considering the formation of a resonance-stabilized α-cyanoalkyl radical as the most probable intermediate which attacks a nitrogen atom of pyrrolidine and that of butylamine or which recombines with pyrrolidine-N-radical and butylamine-N-radical.