bluuebunny/crossref_metadata_2025 huggingface dataset:
Dielectric Relaxation in Substituted Benzaldehydes
Authors: Singh B , Vij J K
Published: July 2006

The measurements of the relative permittivity at frequencies of 1 MHz and 9.274 GHz and of the refractive index at sodium D-line have been carried out at 30°C for o-chlorobenzaldehyde (A), m-chlorobenzaldehyde (B), p-chlorobenzaldehyde (C), o-nitrobenzaldehyde (D), m-nitrobenzaldehyde (E), and P-nitrobenzaldehyde (F), in dilute solutions of benzene, cyclohexane, carbon tetrachloride, p-dioxane and Nujol. The dielectric relaxation times for the overall rotation and the electric dipole moments for these molecules have been calculated. These results have been used to calculate the dipole moment for the internal rotations, possibly of the CHO-group, in the molecule. The results are analyzed in terms of the solute-solvent interactions for these molecules. The bonding between the hydrogen atom of the aldehyde group and the oxygen atom of the dioxane molecule seems to be fairly weak. The comparative behavior of the chlorobenzaldehydes and the nitrobenzaldehydes has also been discussed.
The Crystal Structure of Monoaquobis(1,10-phenanthroline)copper(II) Nitrate, [Cu(H2O)(phen)2](NO3)2
Authors: Nakai Hisayoshi , Deguchi Yoshito
Published: July 2006

The crystal structure of the title compound has been determined from three-dimensional X-ray data collected on Weissenberg photographs, using CuKα radiation. The intensities were estimated visually with a standard scale. The structure was solved by the heavy-atom method and refined by the least-squares method. The final R value was 0.118 for 1835 observed reflections. The space group is C2/c, with a=22.58(2), b=7.23(1), c=16.58(2) Å, β=123.6(1)°, and Z=4. The crystal is composed of [Cu(H2O)(phen)2]2+ cations with C2-symmetry and NO3− anions. The copper atom is surrounded by four nitrogen atoms of the two phenanthroline ligands (average Cu–N=2.01 Å) and a water-oxygen atom (Cu–O=2.18 Å) in a distorted trigonal-bipyramidal arrangement. One oxygen atom and two nitrogen atoms of two different phenanthroline ligands are coplanar with the central copper atom, and lines linking the copper atom with each of the axial nitrogen atoms make angles of about 10°, with the normal to the basal N–N–O plane. The electronic reflectance spectrum of this complex shows a characteristic band at about 12.5×103 cm−1, which is analogous to that of [CuI(bipy)2]I.
Neutron-activation Analysis of Selenium, Osmium and Ruthenium in Rocks, Sediments and Biological Materials by Successive Distillations with Three Kinds of Strong Phosphoric Acid Reagents
Authors: Terada Kikuo , Matsumoto Ken , Kiba Toshiyasu
Published: July 2006

A new separation scheme is presented for the neutron-activation analysis of selenium, osmium and ruthenium in solid samples such as rocks, sediments and biological materials. A neutron-irradiated sample accompanying the carriers of the three elements was heated with the bromide-SPA reagent to 250°C, whereupon selenium came out as gaseous selenium tetrabromide. The second distillation was performed by heating the residual sample with Ce(IV)-SPA reagent till 285°C to separate osmium as osmium tetroxide gas. The last distillation of ruthenium as ruthenium tetroxide followed under heating the residue with the Cr(VI)-SPA reagent till 245°C. Each distillate was absorbed in an appropriate absorbing solution from which selenium metal, osmium thiourea chromithiocyanato complex, and ruthenium metal were respectively recovered and they were submitted to γ-counting by means of a Ge(Li) detector coupled with a multi-channel pulse height analyzer. The chemical recoveries of the added carriers were found to be about 80% for selenium and above 90% for osmium and ruthenium.
The Syntheses of R3Sn–Mn(CO)5−nLn(n=0 or 1) Compounds and Their 119Sn-Mössbauer and 1H-NMR Studies
Authors: Onaka Satoru , Sano Hirotoshi
Published: July 2006

Seven new compounds with the Sn-Mn bond have been prepared by carbonyl displacement with a weaker π-accepting ligand, L (L=P(C6H5)3, As(C6H5)3, Sb(C6H5)3 for R3Sn–Mn(CO)5) or by reaction of the anion [Mn(CO)5]− or [Mn(CO)4P(C6H5)3]− with R3SnX (R=C2H5, n-C3H7, n-C4H9). A trans configuration is deduced for the mono-substituted compounds, R3Sn–Mn(CO)4L, on the basis of the infrared spectra in the v(CO) region. The 119Sn-Mössbauer and IR spectra are measured for sixteen compounds of the R3Sn–Mn(CO)5−nLn type (R=CH3, C2H5, n-C3H7, n-C4H9, Cl, Br, I; L=P(C6H5)3, As(C6H5)3, Sb(C6H5)3; n=0 or 1). Both the Mössbauer isomer shift and the quadrupole splitting increase with an increase in the length of the alkyl chain attached to the tin atom. The replacement of CO on the manganese atom with the weaker π-accepting ligand, L, has a significant effect on the isomer shift and quadrupole splitting of the tin atom through the σ- and π-interaction between the tin and manganese atoms. An interpretation of the change in the chemical shift of the terminal methyl protons is also given for alkyl derivatives.
Degradation of Polyacrylamide Molecules in Aqueous Solutions by High-speed Stirring
Authors: Nagashiro Waichi , Tsunoda Teruo , Tanaka Makoto , Oikawa Mitsuru
Published: July 2006

The viscosity of polyacrylamide aqueous solutions decreases as a result of high-speed stirring, due possibly to the degradation of the molecules.
Investigation of the Concept of Free Volume by Means of a Correlation Function Method
Authors: Arakawa Kiyoshi , Kojima Kazumitsu
Published: July 2006

An investigation of the validity of the free volume theory of liquid has been undertaken on the basis of the theory of correlation functions. A formula for free volume without use of a geometrical model has been proposed and discussed. The magnitude of equivalent free volumes obtained from the formula has been found to be nearly equal to that calculated from the entropy of vaporization by means of the free volume theory. The results give support to the physical reality of the concept of free volumes. The communal entropy deduced agrees with that obtained by an expansion formula to the first order of density. A formula for compressibility has also been derived, which gives satisfactory results in comparison with observed data.
Studies of Surface Modification of Solids. III. Reaction of Silica with Trifluoroethanol
Authors: Tsutsumi Kazuo , Emori Haruo , Takahashi Hiroshi
Published: July 2006

The esterification of silica was performed by reactions with 2,2,2-trifluoroethanol vapor and ethanol vapor with and without basic catalysts, such as ammonia and pyridine. The esterification with ethanol was referred to as the control. The extents of the esterifications were observed by means of infrared spectroscopy. The reactivity of the silica with trifluoroethanol was higher than that with ethanol. This is presumably because trifluoroethanol is more acidic than ethanol. The esterification was accelerated by the addition of ammonia as a base catalyst. For example, in the reaction of the silica with trifluoroethanol of 10.7 Torr at 30 °C for 3 hr, 35% of the surface silanols were esterified without any catalyst, while with the ammonia (0.2 Torr) catalyst, 98% of them was esterified. This suggests that the extraction of the proton from the hydroxyl groups of alcohol by NH3 contributes to the esterification. The addition of pyridine influenced the reaction rate as well, but the esterification itself was disturbed by the addition of excess pyridine, because pyridine was adsorbed strongly on the surface silanol and its heterocyclic ring prevented the alcohols from adsorption. It is supposed that the physical adsorption of trifluoroethanol on the surface silanol is necessary in the first stage of the esterification. The esterified silica became hydrophobic, and it was hydrolyzed in the presence of water.
The Ligation of Phosphine Derivatives and the Oxygen-binding Properties of the Cobalt Mesoporphyrin IX Dimethyl Ester in Toluene
Authors: Takayanagi Teruo , Yamamoto Haruhiko , Kwan Takao
Published: July 2006

The coordination of phosphine derivatives and some other bases to the cobalt mesoporphyrin IX dimethyl ester in toluene has been spectrophotometrically investigated. The coordination equilibrium constants were determined for each base, and found to be of this sequence (25 °C) : P(C4H9)3>>P(OCH3)3>P(C6H5)3>S(CH3)2>As(C6H5)3. The reversible oxygenation of the penta-coordinate complexes formed as above was investigated at lower temperatures (−20–−80 °C): the corresponding equilibrium constants were found to be in the following sequence (−80 °C): P(C4H9)3>P(OCH3)3>S(CH3)2>P(C6H5)3>As(C6H5)3. These relations were discussed in terms of the σ-donating ability of a ligand coordinated trans to oxygen.
The Gas Chromatographic Determination of Carbonyl Compounds as Their Thiosemicarbazone
Authors: Baba Yoshio
Published: July 2006

The gas chromatographic determination of carbonyl compounds in a contaminated air sample via their thiosemicarbazone was studied. As the method utilizes the selective detectability of the flame photometric detector for the sulfur compound, the isolation of the sulfur-containing derivatives of the carbonyl compounds is not required; this eliminates the inaccuracy stemming from the isolation of the derivatives from the sample solution. The isolation and subsequent regeneration of the carbonyl compound was carded out via the thiosemicarbazone metal complex; this affords a practical method of preparing the sample required for the identification of the individual carbonyl compound.
The Steric Effects of Alkyl Groups on the N–H Stretching Vibrations and the Rotational Isomerism of Alkylureas
Authors: Mido Yoshiyuki , Gohda Tamotsu
Published: July 2006

The free N–H stretching vibrations of various trialkylureas, R2UR′, in dilute solutions were studied in order to resolve our questions concerning the rotational isomerism of dialkylureas. In the infrared spectrum of R2UR′, where R is isopropyl or cyclohexyl, an additional N–H band appears on the higher-frequency side of the trans N–H band. It was also observed that the larger the effective size of the R′ group on R2UR′ is, the stronger the intensity of the additional band becomes. It was concluded, in connection with the rotational isomerism of dialkylureas, that the additional band arises from a form in which the N–H group is out of the skeletal plane.
The Formation and Collapse of Mixed Monolayers of 1-Hexadecanol and 1-Octadecanol with Interest in Evaporation Control of Water by Monolayers
Authors: Funasaki Noriaki , Nakagaki Masayuki
Published: July 2006

Collapse pressure, equilibrium spreading pressure, and melting points of binary mixtures of hexadecanol and octadecanol were measured in order to study the phase equilibrium among a monolayer, a solid, and a liquid and to apply the result to evaporation control of water by monolayers. Collapse pressure and equilibrium spreading pressure of solid mixtures have a maximum at a given composition, while the equilibrium spreading pressure of a liquid mixture has not a maximum. Melting points have a minimum at a given composition. From thermodynamic analysis of these phase equilibriums, it was concluded that the mixed monolayer and liquid mixture were ideal solutions, while the solid mixture was a lattice-distorted solid solution. That is, when the two components of different molecular volumes form a solid solution, the solid solution has high energy due to the distortion of the crystal lattice and consequently, it becomes easier to spread and the mixed monolayer becomes more stable against collapse. From these results, the relations between the composition of solid solution and the surface pressure, composition, and specific evaporation resistance of the mixed monolayer in equilibrium with the solid solution, were obtained.
The Raman Spectra and the Phase Transition of 1,2-Dibromoethane
Authors: Hiraishi Jiro , Shinoda Takako
Published: July 2006

The lattice vibrations of 1,2-C2H4Br2 and 1,2-C2D4Br2 were measured by means of Raman spectroscopy. The temperature dependence of the frequencies and the half widths of the lattice vibrations indicates that the phase transition of the crystal is associated with the rotation of the molecule around the Br–Br axis.
Photoelectron Spectroscopic Study of Skew Compounds. Methylhydrazine and Unsymmetrical Dimethylhydrazine
Authors: Kimura Katsumi , Katsumata Shunji , Osafune Kazuteru
Published: July 2006

The He I photoelectron spectra of unsymmetric hydrazines CH3HNNH2 and (CH3)2NNH2 have been measured and CNDO/2calculations have been carried out, in which gauche (outer- and inner-skew) forms and trans form were taken into account for CH3HNNH2. It has been found that nonbonding splittings in the photoelectron spectra are well reproduced by CNDO/2 calculations with gauch forms. The present result of conformation are supported by available conformational studies. The following conclusions have been obtained on orbital assignments of the photoelectron spectra: 1) The first and second bands are due to the methylated and unmethylated nitrogen lone pairs, respectively. 2) The third bands are attributed to the N–N bonding orbitals. 3) The rest of the photoelectron spectra up to 18 eV can be explained in terms of other p-type orbitals (C–N bonding, CH3 pseudo π, and NH2 pseudo π).
The Franck-Condon Factor of a Polyatomic Molecule. Its Method and Application to Acetylene and Dideuteroacetylene
Authors: Kanesaka Isao , Kawai Kiyoyasu
Published: July 2006

An advanced method for the calculation of the Franck-Gondon factor is reported. It is realized on the assumption of the neglect of the zero-point motions except for the three normal coordinates whose vectors are three-dimensionally orthogonal to each other. The overlap integral is given by the Cartesian displacement coordinate system in order to consider precisely the molecular structures of the ground and excited states. This coordinate system does not cause any conflicts with the above assumption. Thus, the overlap integral is defined every nucleus with one- to three-dimensional formulae to satisfy sufficiently the Franck principle, which has been considered precisely only in the case of the diatomic molecule. The method is applied to acetylene and dideuteroacetylene with very good results. The intensity factors obtained are discussed, along with the effects of the force constants and anharmonicity.
Activity Measurement and Colloid Chemical Studies of Aqueous Sodium Tetradecyl Sulfate Solutions
Authors: Koshinuma Masakatsu , Sasaki Tsunetaka
Published: July 2006

A concentration cell using an ion-exchange semipermeable membrane as a septum for the measurement of the activities of ionic surfactants has been constructed, the method of measurement is here in described. The membranes used proved each to be exclusively permeable to one ion. The activities of both the tetradecyl sulfate ion (TS−) and the counterion (Na+) were determined. In the concentration region from 4.0×10−4 mol/1 to CMC, logf±=−(0.070logC+0.283) held for the mean activity coefficient, f±. The f± value at the CMC was found to be 0.81, considerably smaller than the value, 0.978, calculated by the Debye-Hückel equation taking account of the ionic size, 5.5 Å. Above the CMC the activity of the TS− ion decreased, that of the Na+ ion increased, and the mean activity slightly increased with the NaTS concentration. The Gibbs adsorption isotherm was applied for the adsorption of NaTS, using exclusively the observed data of the amount of adsorption, the surface tension, and the activities. A satisfactory agreement was obtained between the amount of adsorption observed and that calculated. The observed decrease in the surface tension above the CMC was confirmed by calculations using the Gibbs adsorption iostherm, the observed data of activity, and the amount of adsorption. The charged-phase separation model was verified as the mechanism of the micelle formation, and the degree of counterion attachment was calculated to be 0.81.
Semi-empirical Localized MO Calculations of Saturated Carbocyclic and Heterocyclic Compounds
Authors: Frenking Gernot , Kato Hiroshi , Hirao Kimihiko , Fukui Kenichi
Published: July 2006

Localized MO calculations have been carried out by the “energy localization” method of Edmiston and Ruedenberg, based upon the INDO MO’s, for 3-, 4-, and 5-membered cycloalkanes and their heterocycles containing one oxygen or nitrogen atom. Furthermore, LMO calculations were performed for the protonated three-membered heterocyclic compounds. The s-nature of the LMO’s is discussed and correlated with the bond angle, the bond moment, the bond energy, and the bond polarity. Some LMO density maps are shown.
Benzoyl Peroxide- and Photo-induced Reactions of Diethyl Mesoxalate in Cyclohexane and Toluene
Authors: Pac Chyongjin , Sakurai Hiroshi , Shima Kensuke , Ogata Youichi
Published: July 2006

Benzoyl peroxide-catalyzed reactions of diethyl mesoxalate in cyclohexane gave ethyl cyclohexylglyoxylate (I) as the main product, accompanied by smaller amounts of diethyl cyclohexylhydroxymalonate (II), ethyl 2-oxobutyrate (III), and diethyl ethylhydroxymalonate (IV), while similar reactions in toluene gave no ethyl phenyl-2-oxopropionate. The a-ketoesters (I) and (III) and the hydroxymalonates (II) and (IV) were considered to arise from β-cleavage and hydrogen atom-abstraction, respectively, of alkoxy radicals A, which take place with addition of cyclohexyl and ethyl radicals to ketonic carbon of diethyl mesoxalate. Irradiation of cyclohexane and toluene solutions of diethyl mesoxalate gave II and diethyl benzylhydroxymalonate (V), respectively, as main products.
Dielectric Relaxation Studies of Trihalogenated Esters in Different Solvents at Microwave Frequency
Authors: Purohit H D , Sharma H S , Vyas A D
Published: July 2006

The dielectric permittivity ε′ and dielectric loss ε″ have been measured at 9.83 GHz for the solutions of four trihalogenated esters in six non-polar solvents having wide range of viscosities at 35 °C. The static permittivity ε0 at 1 MHz and high frequency limiting permittivity ε∞=nD2 have also been measured at 35 °C. The normalized plots of logτ vs. logη for these esters are linear for non-interacting solvents only. The anomalous behaviour of these solutes in other solvents has been explained in terms of solute-solvent interactions. The distribution parameter α, the free energies of activation ΔFτ, ΔFη and the dipole moment μ of these esters have also been reported.
Derivatographic Studies on Transition Metal Complexes. XVI. Thermal Chelation of Na[CoX(Hedta or Hpdta)] and [CoX(Hgly)en2]X2 (X=Cl− or Br−) Type Complexes in Solid Phase
Authors: Tsuchiya Ryokichi , Manzaki Katsuhide , Sekiya Shigeru , Uehara Akira , Kyuno Eishin
Published: July 2006

Thermal chelation of the following two types of complexes in solid phase was investigated by means of derivatography: Na[CoX(Hedta or Hpdta)] and [CoX(Hgly)en2]X2 (X=Cl− or Br−), where Hedta or Hpdta and Hgly designate quinquedentate ethylenediaminehydrogentetraacetate or propylenediaminehydrogentetraacetate ion and unidentate glycine molecule, respectively. The results show that all the complexes undergo characteristic thermal chelation through the dehydrohalogenation, giving an increase in ligand denticity from five to six in Na[CoX(Hedta or Hpdta)] and one to two in Na[CoX(Hgly)en2]X2. The reaction mechanism in the thermal chelation of each complex in solid phase was discussed in terms of the thermochemical data.
The Polarographic Reduction of [Pd(oxine)2] and [Pd(acac)2] in a N,N-Dimethylformamide Solution
Authors: Hirota Michio , Fujiwara Shizuo
Published: July 2006

Palladium(I) species were produced by the polarographic reduction of palladium(II)–oxinate and –acetylacetonate complexes in a N,N-dimethylformamide solution. These species were unstable and decomposed into electro-inactive species through an irreversible following chemical reaction. The rate constants were obtained from the fundamental and second harmonic AC polarograms, which were obtained at two different frequencies of the AC potential, 55.8 and 173.6 Hz, at 22.5 °C as 5.5±1.0 s−1 for the oxinate complex and as 50±10 s−1 for the acetylacetonate complex.
Reaction of Nickel Ion Fixed on the Ion Exchange Resin with 2-Thenoyltrifluoroacetone
Authors: Ohzeki Kunio , Tamura Tooru , Kambara Tomihito
Published: July 2006

The reaction of nickel ions fixed on the ion exchange resin with 2-thenoyltrifluoroacetone was investigated in various organic solvents. In the presence of pyridine, nickel ions were quantitatively extracted from the resin into the organic phase in the form of the adducts of nickel(II) chelate with pyridine. The synergistic effect of a series of pyridine bases on the removal of the metal ions from the resin decreased in the order : pyridine >γ-picoline>β-picoline>α-picoline.
An Electron Spin Resonance Study of Some Quadridentate Schiff Base Complexes of Copper(II)
Authors: Cookson David J , Smith Thomas D , Pilbrow John R
Published: July 2006

The X-band ESR spectra of a series of quadridentate Schiff base complexes of copper(II) have been examined in frozen xylene and chloroform solutions. Well resolved triplet state spectra were observed both at g ca. 2 and g ca. 4 due to dimeric forms of these complexes which exist in frozen solution. Magnetic and structural parameters have been determined by computer simulation of the triplet state spectra based on a lower than axial symmetry model for the copper(II) pair system.
The Nucleophilic Photo-substitution Reaction of Anthraquinone Derivatives. II. The Mechanism of the Photoamination of Sodium 1-Amino-4-bromoanthraquinone-2-sulfonate
Authors: Inoue Haruo , Nakamura Kenichi , Katô Seijiro , Hida Mitsuhiko
Published: July 2006

The photoamination of sodium 1-amino-4-bromoanthraquinone-2-sulfonate (I) by ammonia or alkylamines in aerated 4 : 1 2-propanol-water was investigated. No effect on the reaction was observed by the addition of Rose Bengal as the addition of the triplet quenchers. The reciprocal of the quantum yield was proportional to the reciprocals of both the partial pressure of oxygen and the concentration of the amine. The peroxide was produced as the photoamination proceeded, and the simultaneous photodecomposition took place in a constant ratio to the photoamination. This reaction scheme for the photoamination of (I) was proposed: the exciplex was formed by the excited (I) (1CT) and the ground-state oxygen, followed by the nucleophilic attack of the amine.
Synthesis of [4-5,4′-5′-Bis(δ-Aminovaleric Acid)]-Gramicidin S
Authors: S\={o}fuku Sh\={o}suke , Muramatsu Ichiro , Okada Kazuki , Hagitani Akira
Published: July 2006

An analog of gramicidin S, [4-5,4′-5′’-bis(δ-aminovaleric acid)]-gramicidin S, was synthesized, in which both of the two residues of d-Phe-l-Pro of gramicidin S (GS) were replaced with δ-aminovaleric acid residues (δAva). The spectra of optical rotatory dispersion (ORD) and circular dichroism (CD) of this analog suggest that its conformation in solution at room temperature is a random structure by comparison with that of GS. This analog has no antimicrobial activity. The linear peptide H-(Val-Orn-Leu-δAva-)2-OH also has no activity and its ORD and CD are nearly the same as those exhibited by the random structure of the polypeptide. These results indicate the importance of the presence of d-Phe-l-Pro in GS for the maintenance of the specific conformation.
α-Thiocarbonyl-stabilized Triphenylphosphonium Ylides: Preparation, Structure, and Alkylation Reactions
Authors: Yoshida Hiroshi , Matsuura Hironori , Ogata Tsuyoshi , Inokawa Saburo
Published: July 2006

A number of α-thiocarbonyl-stabilized ylides II were prepared in moderate yields, and their alkylation reactions were studied. II(H, MeO), II(H, EtO), II(H, i-PrO), and II(H,H) were mixtures of cis and trans isomers, and the IIcis⁄IIItrans ratios were solvent-dependent. II(H, Ph), II(H, Me2N), II(H, MeS), and II(H, EtS) were composed of only cis isomers. All these ylides II with alkyl iodide gave S-alkylation products in good yields.
Determination of Amino Acid Sequence of Peptides by the Combination of Mass Spectrometry and Edman Degradation. Alternate Use of p-Chloro- and p-Bromophenylisothiocyanate Followed by Modification of Shortened Peptide
Authors: Murai Asao , Takeuchi Yoko
Published: July 2006

It was shown that the alternate use of p-chloro- and p-bromophenylisothiocyanate for Edman degradation makes it possible to determine the amino acid sequence of peptides more unambigously by mass spectrometry, i.e., by the doublet molecular ions of phenylthiohydantoin derivatives of amino acids with the intensity ratio inherent to the natural abundance of each halogen atom. The amino acid sequence of the shortened peptide could also be surely determined by the deuterium labeled mixed acylation by shifting the “sequence determining peaks” to higher mass region where no interfering peaks for the interpretation of the mass spectra would appear as well as labeling them as doublets with equal intensities by the distance of 2 mass units. Two examples, a dodecapeptide H–(Pro–Pro–Gly)4–OH, and an octapeptide angiotensin II, were presented.
Stereoselective Synthesis of 1,4,4a,9a-Tetrahydro-9-fluorenone Bearing trans Angular Substituents
Authors: Kusumi Takenori , Imaye Kiyoto , Kakisawa Hiroshi
Published: July 2006

An intramolecular Friedel-Crafts reaction of 2-methyl-1-phenyl-1,2,3,6-tetrahydrophthalic anhydride 6 followed by methylation afforded new types of fluorenones bearing trans angular substituents, 4a-carbomethoxy-trans-9a-methyl-1,4,4a,9a-tetrahydro-9-fluorenone 7 and 3-hydroxy-trans-9a-methyl-9-oxo-1,2,3,4,4a,9a-hexahydrofluoren-cis-4a-carboxylic anhydride 10.
Electric Dipole Moment of Pyrrole and Molecular Interaction in Solution
Authors: Srivastava A N , Joshi V K
Published: July 2006

Literature reports two values for μs/μv namely 1.06 and 0.9 for pyrrole in benzene solution. Our orientation polarisation data on pyrrole discussed in terms of Higasi’s theory favours the former. Further we observe that in benzene the solute forms donor-acceptor complexes, while in carbon tetrachloride it undergoes association through hydrogen bonding.
The Electronic Absorption Spectra of UV Irradiated Anilines Adsorbed on Porous Vycor Glass
Authors: Sakata Tadayoshi , Okai Toshihiro , Sugimoto Hiroaki , Tsubomura Hiroshi
Published: July 2006

Cation radicals of aniline and its derivatives were formed on porous Vycor glass plates by UV-irradiation. One of the absorption bands appearing in the visible region is assigned to the transition to the first excited state of the cation radical by comparison with the reported photoelectron spectrum. The charge resonance band of the dimer cation was also observed in the near infrared region in most cases.
Micellar Effect of Alkylammonium Propionates on Reaction Rate of Keto-Enol Tautomerism in Cyclohexane
Authors: Kon-no Kijiro , Miyazawa Kiyoshi- , Kitahara Ayao
Published: July 2006

The rate of keto-enol transformation of acetylacetone or acetoethyl acetate was spectroscopically measured in the cyclohexane solutions in the presence of primary, secondary or tertiary alkylammonium propionate. The rate was enhanced by micelle formed. The order of effectiveness of the surfactants was that primary>>secondary> tertiary. The order coincides with the number of protons in the ammonium ion of the surfactants and the aggregation number of micelle.
The Solubilities and the Solubility Parameter of Heptasulfur Imide
Authors: Hamada Shuichi , Kudo Yoshiyuki , Kawano Masako
Published: July 2006

The solubilities of heptasulfur imide in eleven organic solvents were measured. The solubility parameter of heptasulfur imide was estimated to be 12.7 at 25 °C from the solubilities and the activity deduded from the enthalpy of the fusion; we assumed the solutions to be regular.
Nitrosylrhodium (14NO and 15NO) Compounds Containing Triphenylphosphine
Authors: Miki Eiichi , Mizumachi Kunihiko , Ishimori Tatsujiro
Published: July 2006

The oxidation states of the NO group and the geometries for the nitrosylrhodium compounds were investigated on the basis of the 15N-isotopic shifts of the N–O stretching vibrations and the frequencies of the Rh–NO stretching ones. RhCl(NO2)(NO)(PPh3)2 was found to react with NO to give RhCl(NO2)2(PPh3)2.
A Theoretical Model for the Hydrogen Migration of Butyl Alcohol
Authors: Takagi Tsutomu , Oiwa Masayoshi
Published: July 2006

The hydrogen-migration mechanism of the fragmentation of n-butyl alcohol in a mass spectrometer is discussed from the standpoint of the bonding interaction energy, as estimated by an all-valence electron semi-empirical SCF-MO treatment (CNDO/2-UHF), assuming the following models I and II:

(Remark: Graphics omitted.)

Finally, Model I is suggested to be energetically favorable.
The Total Synthesis of (±)-Royleanone
Authors: Tachibana Yakudo
Published: July 2006

The total synthesis of (±)-royleanone (I) has been achieved. 5,7,8-Trimethoxy-1-tetralone (III) was converted into (±)-5,7,8-trimethoxy-1-methyl-2-tetralone (VII) via a dihydronaphthalene derivative (IV). The annelation of VII with methyl vinyl ketone gave a (±)-hexahydro-2-oxophenanthrene derivative (VIII), which was then further converted into (±)-11,12,14-trimethoxy-3-oxopodocarpa-5,8,11,13-tetraene (IX). The hydro-genation of IX over platinum oxide gave two dihydro derivatives, (X) and (XI), in a ratio of ca. 1 : 7, these configurations in the A/B ring juncture were identified as trans and cis respectively. Therefore, IX was subjected to thioketalization, followed by desulfurization, to give (±)-11,12,14-trimethoxypodocarpa-5,8,11,13-tetraene (XV). The hydrogenation of XV over 10% palladium on carbon gave (±)-11,12,14-trimethoxypodocarpa-8,11,13-triene (XII), along with a small amount of its cis isomer (XIII). Finally, XII was converted into a hydroxy-1,4-quinone derivative (XIX), which was then treated with isobutyryl peroxide to give (±)-I, whose IR, UV, and NMR spectra were identical in every respect with those of natural royleanone.
The Reaction of N-Phenylsulfonyl Thione S-Imide with Acyl Halides
Authors: Tamagaki Seizo , Sakaki Keishi , Oae Shigeru
Published: July 2006

Thiocarbonyl S-imide of 1,2-dithiole-3-thione reacted with various acyl halides producing the corresponding N-phenylsulfonyl-1,2-benzodithiole-3-imine and elemental sulfur. The reaction was found to proceed via initial acylation on the nitrogen of the imide and was essentially acyl halide-catalyzed with regard to rearrangement.
Cryptate Chemistry. I. The Reaction of Potassium Alkanoates with Alkyl Halides in the Presence of 4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane
Authors: Akabori Sadatoshi , Ohtomi Michiko
Published: July 2006

Potassium alkanoates reactes with organic halides in the presence of bicyclopolyether (III) in benzene to give esters in high yields.
Diels-Alder Reaction of 2-Methyl-2-cyclohexenone and Substituted Butadienes
Authors: Nagakura Isao , Ogata Haremi , Ueno Masako , Kitahara Yoshio
Published: July 2006

Diels-Alder adducts of 2-methyl-2-cyclohexenone and substituted butadienes were obtained in a high yield in the presence of catalytic aluminum chloride.
Surface Dilational Properties of Adsorbed Monolayers of Aqueous Sodium Dodecyl Sulfate Solutions
Authors: Nakamura Masao
Published: July 2006

The surface pressure relaxation of a freshly formed surface and the surface area creep at a constant surface pressure have been studied for aqueous surface of sodium dodecyl sulfate solutions. It was found that the area stress after the formation of a fresh surface undergoes relaxation according to the generalized Maxwell model, and that the surface area viscosity is not constant during the process but increases with the surface area. The concept of two-dimensional open system rheology was introduced and the observed phenomena were discussed. A surface equation of state applicable under such dynamic conditions has been derived.
Heat Capacity Changes of Alkyl-substituted Ammonium Chlorides in Aqueous Solutions
Authors: Tamaki Kunio , Yoshikawa Satoru , Kushida Mitsuyoshi
Published: July 2006

The changes in the heat capacity for the dissolution in water, ΔCP°, of n-alkylammonium chlorides (methyl to hexyl), di-n-alkylammonium chlorides (methyl to butyl), and tri-n-alkylammonium chlorides (methyl to propyl) at the room temperature were determined from measurements of the relation between the heats of solution of these salts in water and the temperature, and the results were compared with the ΔCP° values for tetraalkylammo-nium salts in the literature. It was found that the effect of the coordination of the charge-bearing nitrogen atom by alkyl groups was definitely reflected in the ΔCP° values. In the cases of MeNH3Cl, EtNH3Cl, Me2NH2Cl, and Me3NHCl, the ΔCP° values are negative, while in the cases of other higher homologues, the ΔCP° values are positive; the increments in the ΔCP° values per methylene group are discussed in terms of the hydrophobic hydra-tion and the steric effect of alkyl chains.
The Determination of the Activity Coefficients of Pb(II), Cd(II), and Zn(II) Chlorides in N,N′-Dimethylformamide by Means of Electromotive-force Measurements of the M(Hg)/MCl2(DMF)/AgCl; Cells
Authors: Saito Makoto , Kanamori Akemi
Published: July 2006

Electromotive-forces have been measured for the cells of the M(Hg)/MCl2(DMF)/AgCl;Ag type at 25.00±0.01 °C, where M are Pb, Cd, and Zn metals and were M(Hg) are amalgams saturated with these metals. The standard potentials of the corresponding metals relative to the silver-silver chloride have been determined, and the mean activity coefficients and the standard free-energies of formation have been calculated for the solvated salts of PbCl2, CdCl2, and ZnCl2 from the electromotive-foce data. Experimental works were carried out by using an H-shaped Pyrex glass cell which was coated externally with silicon grease to eliminate electrical leakage from the water bath. The electromotive-force measurements were made with a digital voltmeter, the voltage sensitivity and the input impedance of which were 10 μV and 100 megohms respectively. The standard potentials for the cells of the M/MCl2(DMF)/AgCl;Ag type were 0.3271 for PbCl2, 0.5762 V for CdCl2 and 0.8986 V for ZnCl2.
The Application of Molecular-flame-absorption Spectroscopy to the Elucidation of Chemical Interferences in Indium Atomic Absorption Spectrometry
Authors: Haraguchi Hiroki , Fuwa Keiichiro
Published: July 2006

The atomic absorption spectrometry of indium was investigated in air-acetylene and nitrous oxide-acetylene flames. The atomic absorptions of indium were significantly interfered by HCl, HClO4, and HBr in both the flames. The chemical interferences can be explained by the formation of diatomic molecules, such as InCl and InBr, the molecular absorption spectra of which were really observed in flames.
N-Halogen Compounds of Cyanamide Derivatives. V. The Preparation and Reaction of Δ4-1,2,4-Thiadiazolines
Authors: Fuchigami Toshio , Odo Keijiro
Published: July 2006

Five new Δ4-1,2,4-thiadiazolines (TDZ), IIa,b, IIIa,b, and IV, were easily prepared by the reaction of potassium methyl cyanoiminodithiocarbonate (I) with N-chloro compounds of O-alkylisoureas, guanidines, and guanylurethane. 2-Methoxyimidoyl-3-imino-5-methylthio-TDZ (IIa), with a reactive imidoether group, was converted into the 2-carbamoyl-TDZ derivative (V) by treatment with excess dry hydrogen chloride. The reaction of IIa with aliphatic amines gave 2-amidino-TDZ derivatives (IIIc–e) in good yields in the presence of both free amines and amine hydrochlorides (molar ratio, 2:1). The mechanism of this amidination was discussed.
The Additions of Acetic Acid to Limonene Catalyzed by Sulfuric Acid
Authors: Yamanaka Tohr
Published: July 2006

The additions of acetic acid (AcOH) to limonene (IV) catalyzed by H2SO4 ((0.367–8.39)×10−2 mol/l), without a solvent, were studied. The mole ratio of IV to AcOH was less than 1: 19, and the reaction temperature was 28.5–92.5 °C. The products were α- and β-terpinyl acetates (I and II), and a mixture of p-menthadienes (III) as isomers of IV. The selectivity for I and II against III was not affected by the amount of H2SO4. The rate constants for I, II, and III were proportional to the amount of H2SO4. The apparent activation energy was 10.9 kcal/mol for I and II, and 13.7 kcal/mol for III. Both the proton concentration and the acidity function (h0) in the reaction medium were regarded as proportional to the H2SO4 concentration. It was concluded that the formations of I and II were related to the A-2-type solvolytic mechanism, while that of III was related to the A-1-type specific hydrogen-ion mechanism.
The Synthesis and Ion-exchange Properties of TiH2(PO4)2·1/2H2O
Authors: Kobayashi Etsuro
Published: July 2006

In order to develop an ion-exchanger for industrial use, a new compound, titanium dihydrogen bis (phosphate) hemihydrate, was prepared by means of a reflux between titanium phosphate and concentrated phosphoric acid; then the conditions of synthesis and the ion-exchange properties of the products were investigated. The amorphous titanium phosphate used as the starting material was formed by the reaction of titanium tetrachloride with phosphoric acid in diluted hydrochloric acid. The phase equilibrium of the TiO2–P2O5–H2O system has been studied at the refluxing temperatures of the mother liquors. The solid phase in equilibrium with the mother liquor containing 13–64% P2O5 had the components of TiO2 (29–32%), P2O5 (53–54%), and H2O (15–16%); its composition was TiH2(PO4)2·H2O, which had already been known, but the solid phase in equilibrium with the mother liquor containing more than 64% P2O5 had as components TiO2 (31–32%), P2O5 (57–58%), and H2O (10–11%); therefore, its composition corresponded to TiH2(PO4)2·1/2H2O. The X-ray diffraction pattern of this compound was entirely different from that of monohydrate, and some large d-values were recognized. From the DTA and TGA, the processes of the dehydration of monohydrate and hemihydrate were also different from each other; however, both compounds were converted to titanium pyrophosphate (TiP2O7) at 800 °C. TiH2(PO4)2·H2O can adsorb sodium ions, but the ions of a large radius, such as potassium and cecium, are not adsorbed. In contrast to this, TiH2(PO4)2·1/2H2O had an excellent ion-exchange property; its ion-exchange capacities were 4.0 meq/g to K+ and 2.0 meq/g to Cs+ at pH 4. These capacities were about eight times those of monohydrate. The solubilities of the phosphate used as an ion-exchanger were remarkably low. Therefore, the titanium dihydrogen bis (phosphate) hemihydrate thus obtained may be utilized as a useful inorganic ionexchanger for potassium and cesium ions.
The Thermal Changes in Gels of the SiO2–Al2O3–Sc2O3–H2O System
Authors: Kasai Mitsuhiro , Hamada Shuichi
Published: July 2006

The DTA patterns of synthesized coprecipitated gels, the SiO2–Al2O3–Sc2O3–H2O system, resembled that of allophane as well as those of coprecipitated gels, the SiO2–Al2O3–M2O3–H2O system (M: Fe, Ga, or In). The exothermic reaction around 980 °C in the DTA was confirmed to arise from the formation of mullite. The scandium-rich coprecipitated gels showed a new small exothermic peak at about 1000 °C, based on the formation of thortveitite in the DTA. The apparent activation energy for the mullite formation on the coprecipitated gels decreased with an increase in the scandium content. A large portion of the scandium in the coprecipitated gels was deposited as the thortveitite by heating, while that in the mixed gels was deposited as the scandium oxide. The behavior of such trivalent cations as gallium, iron(III), indium, and scandium in the silicoalumina gels was discussed.
The Polarography of trans-Cobalt(III) Complexes of Tetradentate Schiff Bases and α-Methylbenzylamine in N,N-Dimethylformamide and Methanol Solutions
Authors: Kodama Mutsuo
Published: July 2006

The polarographic behavior of mixed-ligand cobalt(III) complexes of tetradentate Schiff bases and α-methylbenzylamine (pheNH2) of the general formula of [CoZ(pheNH2)2]+ in methanol and N,N-dimethylformamide solutions was studied. At the dropping mercury electrode, these metal complexes give well-defined, two-step waves corresponding to the reduction of cobalt (III) to cobalt(II) and that of cobalt(II) to cobalt(I). A careful and systematic study of their polarographic behavior revealed that the reaction mechanism in the presence of uncomplexed pheNH2 can be formulated as:

& [CoZ(pheNH_2)_2]^++e^-\ightleftarrows[CoZ(pheNH_2)_2]^0

& [CoZ(pheNH_2)_2]^0+e^-\ightleftarrows[CoZ(pheNH_2)_2]^-

while, in the absence of pheNH2, the reaction mechanism for the second step of the N,N′-ethylenebis(acetylacetoneiminato) and N,N′-ethylenebis(benzoyIacetoiminate) systems is given by:

[CoZ(pheNH_2)_2]^0+e^-\ightleftarrows[CoZ(pheNH_2)]^-+pheNH_2

This can be ascribed to the labile nature of the axial ligand, pheNH2, in these two complexes. The introduction of halogen atoms on the methyl or methylene carbon of N,N′-ethylenebis(acetylacetoneiminato) and that of the benzene ring on the framework of the equatorial ligand remarkably shifted the half-wave potential towards more positive potentials. This fact suggests the electron withdrawal from the cobalt atom by these groups. Furthermore, by examining the nature of the half-wave potentials the redox orbitals of N,N′-ethylenebis(salicylideneaminato) and o-phenylenebis(salicylideneaminato) systems were concluded to be essentially different from those of other Schiff-base systems.
The Crystal Structure of β-K4SiW12O40·9H2O Containing an Isomer of the Keggin Ion
Authors: Matsumoto Kazuko Y , Kobayashi Akiko , Sasaki Yukiyoshi
Published: July 2006

β-K4SiW12O40·9H2O is orthorhombic, with the space group Pnma and a=20.62(1), b=15.57(1), c=12.95(1) Å, Dm=4.88 g cm−3 and Dx=5.04 g cm−3 for Z=4. The crystal contains a discrete β-SiW12O404− polyanion, a geometrical isomer of the α-SiW12O404− with the well known Keggin structure. The idealized Keggin ion has a Td symmetry, but the β-isomer has only a Cs symmetry. Mutual transformation between the α- and β-structures is possible through a 60° rotation of one of the four W3O13 units, which make a cage around a SiO4 tetrahedron in both structures. The other possible geometrical isomers of the Keggin structure are discussed.
Metal Complexes of Amino Acids. VIII. Carbon-13 Nuclear Magnetic Resonances of Cobalt(III) Complexes Containing l-Aspartic and l-glutamic Acids
Authors: Yasui Takaji , Ama Tomoharu
Published: July 2006

The 13C NMR spectra of cobalt(III) complexes containing l-aspartic acid or l-glutamic acid as unidentate, bidentate, or bridged ligand were measured, and the relationship between the coordination types and the changes in chemical shift of carboxyl carbons in these amino acid complexes was discussed. Two structural isomers were newly separated for the trans (O)-[Co en2(l-aspH2 or l-gluH2)2]X3 complex by a column chromatographic method. The structures of the earlier eluted isomers for the trans(O)-[Co en2(l-aspH2)2]X3 and -[Go en2(l-gluH2)2]X3 complexes were assigned to trans(O0) Oγ) and trans(O0, Oδ) (O0, Oγ and Oδ indicate the coordinated oxygen atoms of C0OO, CγOO, and CδOO), respectively, and the structures of the later eluted isomers for the both complexes to trans(O0, O0), on the basis of the shift patterns of carboxyl carbons.
Adducts of Bis(hexafluoroacetylacetonato)metal(II) with Uni-and Bidentate Nitrogenous Bases
Authors: Izumi Fujio , Kurosawa Ryoko , Kawamoto Hiroshi , Akaiwa Hideo
Published: July 2006

Base adducts of the types: M(hfa)2(py)2, M(hfa)2phen, and M(hfa)2bpy [M=Co(II), Ni(II), Cu(II), and Zn(II); Hhfa=hexafluoroacetylacetone; py=pyridine; phen=1,10-phenanthroline; bpy=2,2′-bipyridine] were prepared, and their infrared spectra were examined in detail. These adducts have a cis-octahedral configuration except for Ni(hfa)2(py)2. The metal-oxygen stretching frequencies of the adducts in the 405–370 cm−1 region decrease along the series: nickel(II)>cobalt(II)>copper(II)>zinc(II). Adduct formation leads to the marked weakening of Cu–O bonds in the copper(II) adducts, which is ascribable to the equatorial ligation of the neutral bases. The mass spectral studies of M(hfa)2phen and M(hfa)2bpy revealed that the addition of a neutral ligand affects the fragmentation of the complex remarkably. The exceptional behavior of Cu(hfa)2phen under electron impact is explained in terms of the tendency of copper(II) ion to undergo valency change.
The Crystal Structure of Trichlorotin–pentacarbonylmanganese, Cl3Sn–Mn(CO)5
Authors: Onaka Satoru
Published: July 2006

The crystal structure of trichlorotin–pentacarbonylmanganese, Cl3Sn–Mn(CO)5, has been determined by means of X-ray diffraction. The crystal is monoclinic; a=14.10(1), b=13.38(5), c=13.27(2) Å, and β=97.39(21)° with the P21/c space group and with Z=8. The structure, established by the heavy-atom method, has been refined by a least-squares method based on 2581 reflections collected by diffractometry to give an R value of 10%. The asymmetric unit contains two quite similar molecules. The geometry around the tin atom is distorted tetra-hedrally, while the manganese atom exhibits a distorted octahedral coordination. The four equatorial carbonyl groups are displaced from the equatorial plane toward the tin atom. There is an approximate mirror plane through the Sn–Mn–CO(axial) axis. The Sn–Mn bond distance, 2.590(5) Å, is shorter by about 0.08 Å than that of the triphenyl and trimethyl analogues. The mean Mn–C distance of 1.87 Å is longer than that of the trimethyl analogue. These changes in bond distances may be interpreted in terms of the π-interaction between the two metal atoms, which is more pronounced in the chloro-derivative than in the methyl derivative.
An X-Ray Diffraction Study of the Structures of the Hexachloro-and Hexabromoplatinate(IV) Ions in Aqueous Solution
Authors: Maeda Masunobu , Akaishi Takeshi , Ohtaki Hitoshi
Published: July 2006

The structures of the PtCl62− and PtBr62− complexes in aqueous solution were determined by means of X-ray diffraction measurements of concentrated solutions of hexachloro- and hexabromoplatinic acids. Analysis of X-ray scattering data showed that the PtCl62− and PtBr62− complexes have a regular octahedral symmetry. The interatomic distances within the complexes are: Pt–Cl, 2.33 Å; cis-Cl–Cl, 3.30 Å; trans-Cl–Cl, 4.66 Å; Pt–Br, 2.47 Å; cis-Br–Br, 3.50 Å; trans-Bv–Br, 4.94 Å. These distances are in good agreement with those reported in crystals of hexahalogenoplatinate(IV) compounds.
Photolysis of Methyl Benzenesulfonate in Methanol
Authors: Izawa Yasuji , Kuromiya Naoki
Published: July 2006

The irradiation of methyl benzenesulfonate (1) in methanol undergoes a photolysis (Φdisapp=0.07±0.005) leading to benzene (5–34%), biphenyl (9–15%), and anisole (trace), in place of a photo-addition of methanol to give bicyclohexene derivatives. The rate of desulfonation of 1 is only slightly affected by triethylamine. Stern-Volmer quenching by piperylene occurs and the results suggest a significant singlet participation in this photolysis.
The Photosensitized Oxygenation of Furanoeremophilanes. I. The Isomeric Hydroperoxides from Petasalbin and Their Transformations to Lactones
Authors: Naya Keizo , Kanazawa Reizo , Sawada Michikazu
Published: July 2006

The photosensitized oxygenation of petasalbin I gave almost quantitatively a crystalline mixture of two isomeric hydroperoxides, V-a and V-b, both of which were then transformed to the corresponding lactones, VI-a and VI-b, respectively, in good yields. The stereochemistry of these hydroperoxides and lactones has been established by spectral and chemical methods. Furthermore, two natural lactones, III and IV, were prepared by the reduction of the hydroperoxides.
Favorable Conformations of 2-Amino-2-deoxy-d-hexopyranose Derivatives
Authors: Taga Tooru , Osaki Kenji
Published: July 2006

The conformational free energies of 2-amino-2-deoxy (hydrochloride) and 2-acetamido-d-deoxy derivatives of d-glucose, d-galactose, and d-mannose were calculated by using the empirical potential functions. The most stable conformations of these amino sugars were obtained for α- and β-anomers in the Cl and 1C chair forms through the procedure of searching for the energy minimum. The results of the energy calculations indicate that the increased anomeric effect in the protonated and N-acetylated amino derivatives in an aqueous solution is mainly due to the electrostatic interaction between the positive-charged amino group on C(2) and the hydroxyl group on the anomeric carbon atom, C(1).