bluuebunny/crossref_metadata_2025 huggingface dataset:
The Microwave Spectrum, the rs Structure and the Dipole Moment of the TT Isomer of Diethyl Ether
Authors: Hayashi Michiro , Kuwada Kazunori
Published: July 2006

The microwave spectra of six isotopic species of diethyl ether were measured in relation to the molecular form and dipole moment. Transitions of the TT(trans-trans) isomer could be assigned and the rs structure of this isomer was obtained by the substitution method. The structural parameters of the TT isomer of diethyl ether are; r(CO) 1.408 Å, r(CC) 1.516 Å; α(COC) 112°25′, α(OCC) 108°37′ for the skeleton; r(CH) 1.093 Å, α(CCH) 110°11′, α(OCH) 110°10′, α(HCH) 107°29′ for the CH2 group and r(CH) 1.090 Å, α(CCHs) 110°35′, α(CCHa) 110°15′, α(HsCHa) 108°48′, α(HaCHa) 108°4′ for the CH3 group. The dipole moment was determined to be 1.061±0.018 D from the Stark effect measurement for the TT isomer. A discussion was made on the structure and the dipole moment of the TT isomer of diethyl ether in comparison with those of the similar molecules.
Transition-metal Complexes of Pyrrole Pigments. X. Divalent and Trivalent Manganese Chelates of Dipyrromethenes
Authors: Murakami Yukito , Sakata Kazunori , Harada Kenji , Matsuda Yoshihisa
Published: July 2006

The solution spectra of two tris(dipyrromethenato)manganese(III) complexes and of one bis(dipyrromethenato) manganese (II) as well as the diffuse reflectance spectrum for the latter were examined. The high spin state was confirmed for all the manganese complexes by magnetic susceptibility measurements. For the tris-complexes, one broad low energy band (∼9500 cm−1) is assigned to the 5A1g←5B1g transition and one pair of higher energy bands (∼14000 cm−1) are attributed to the 5B2g←5B1g and 5Eg←5B1g transitions for a D4h symmetry as a consequence of Jahn-Teller effect. In the bis-complex, manganese(II) is placed in a tetrahedral ligand field and one group of ligand-field bands lying below 16000 cm−1 are assigned to: 4T1(4G)←6A1(6S), 4T2(4G)←6A1(6S), and 4E, 4A1(4G)←6A1(6S) in an increasing order of energy. The exceedingly high intensity of these bands is ascribed to the covalent nature of coordinate bonds. A strong IR band due to the skeletal stretching mode of the dipyrromethene moiety was observed in the 1600 cm−1 range and shifted slightly toward lower energy upon metalcoordination.
Nitrosylrhenium(14NO and 15NO) Complexes
Authors: Miki Eiichi , Mizumachi Kunihiko , Ishimori Tatsujiro
Published: July 2006

The 15NO-complexes for M2[ReX5(NO)] (M=Rb, Cs, and pyH; X=Cl and Br) were prepared. The 15N-isotopic shift for their N–O stretching vibrations, ca. 40 cm−1, supports the view that the oxidation state of the NO group is I, while that of the rhenium atom is II. The Re–(NO) stretching and the Re–(NO) bending vibrations were observed in the 610–620 cm−1 region. A new compound, cis-(pyH)[ReCl4(NO)2], was prepared, the oxidation state of its rhenium atom being considered to be I, and that of the NO group, I.
The Synthesis of Coenzyme Q
Authors: Inoue Seiichi , Yamaguchi Ryohei , Saito Kenji , Sato Kikumasa
Published: July 2006

A new, efficient synthesis of coenzyme Q is described. The bromination of 2,3-dimethoxy-5-methyl-p-benzoquinone gives 6-bromo-2,3-dimethoxy-5-methyl-p-benzoquinone, which is then converted to the corresponding hydroquinone diacetate by the action of zinc dust in acetic anhydride. 6-Bromo-2,3-dimethoxy-5-methylhydroquinone diacetate is reacted with 1,1-dimethyl-π-allylnickel bromide in hexamethylphosphoramide at 60 °C to afford a 70% yield of 2,3-dimethoxy-5-methyl-6-prenylhydroquinone diacetate, which is hydrogenolyzed with lithium aluminum hydride in ether and then oxidized with aqueous ferric chloride to give coenzyme Q1 in 76% yield. Similarly, coenzyme Q2, Q9, and Q10, and 6′, 10′, 14′-hexahydrocoenzyme Q4 are synthesized by the reaction of the aryl bromide with π-geranyl-, π-solanesyl-, π-decaprenyl-, and π-phytylnickel bromide respectively and by subsequent treatment with LiAlH4 and FeCl3. The stereochemistry of the products is also described.
Molybdenum(V) Chloride as a Reagent for cis Chlorination of Olefins
Authors: Uemura Sakae , Onoe Akira , Okano Masaya
Published: July 2006

Treatment of nonconjugated olefins such as cis- and trans-2-butenes, cis-2-octene, and cyclohexene with MoCl5 in CCl4 gave vic-dichloroalkanes whose cis-isomer was formed predominantly, the ratio of cis- to trans-addition being 4.9–12.1, together with monochloroalkanes. Preferential formation of exo-cis-dichloride was observed in the case of norbornene and norbornadiene. Bromochlorination and chloroiodination of olefins, and aromatic bromination and iodination were carried out with mixtures of MoCl5 and halogens. The reaction scheme for chlorination is discussed.
Studies on the Synthesis of Histidine Peptides. I. Nim-Tosylhistidine Derivatives as Starting Materials
Authors: Fujii Toshiyuki , Sakakibara Shumpei
Published: July 2006

N α-Nps-, Z(OMe)-, Z-, Boc-, and Aoc-derivatives of Nim-tosylhistidine were synthesized as materials for the syntheses of histidine-containing peptides, and the reactivity of the Nim-tosyl group was examined under several conditions commonly used for peptide syntheses. Although the Nim-tosyl group was somewhat more unstable than Nim-benzyl group, the use of the tosyl derivative was found to be advantageous in several points: the enhancement of the solubility of its peptide derivatives, the suppressive effect of racemization during its coupling reactions, and the high removability of the tosyl group under mild conditions.
On the Additivity of π-Bond Energies in Linear Polyenes
Authors: Aihara Jun-ichi
Published: July 2006

The additivity of π-bond energies in linear polyenes was confirmed by taking nonaromatic [infinity]-annulene and -polyene as reference compounds. The π-bond energies determined by Hess and Schaad were found to be oriented to polyenes of a medium size.
Photocycloaddition of Thiocarbonyl Compounds to Multiple Bonds. X. Photocycloaddition of O-Alkyl Thiobenzoates to Olefins
Authors: Ohno Atsuyoshi , Koizumi Tamotsu , Akasaki Yutaka
Published: July 2006

Photochemical reactions of O-ethyl and O-methyl thiobenzoates with various olefins have been studied. Some olefins afford ketones, others yield thietanes, and in some cases both products are obtained. Thiobenzoate O-esters in the n,π* triplet state are the reacting species. The mechanism of the reaction has been elucidated: photocycloaddition of a thioester to an olefin results in the formation of a thietane. Photosensitized decomposition of the thietane yields an α,β-unsaturated ether, which is converted to a ketone by general acid-catalyzed hydrolysis.
The Structure-Taste Relationships of the Dipeptide Esters Composed of l-Aspartic Acid and β-Hydroxy Amino Acids
Authors: Ariyoshi Yasuo , Yasuda Naohiko , Yamatani Tetsuo
Published: July 2006

In order to evaluate the contribution of a hydroxyl group to the degree of sweetness of aspartyl dipeptides, we have synthesized a number of α-l-aspartyl dipeptides, such as the esters of α-l-aspartyl-l-hydroxynorleucine (16 and 17), -O-acyl-l-serine (18–21), -d-serine (22–28), -d-threonine (30–36), and -d-allothreonine (37–43); their sweetness potencies were compared with those of the corresponding dipeptides without a hydroxyl group. It has been found that a hydroxyl group makes a major contribution to the sweetness of the α-l-aspartyl dipeptide esters. Trie introduction of a hydroxyl group into the l-l peptides gave compounds with reduced potency. However, no such regularity was observed in the l–d peptides; the esters of α-l-aspartyl-d-serine (22–28) and -d-threonine (30–36) were sweeter than the corresponding esters of α-l-aspartyl-d-alanine and -d-α-amino-n-butyric acid respectively, while the esters of α-l-aspartyl-d-allothreonine (37–43) were less sweet than the corresponding esters of α-l-aspartyl-d-α-amino-n-butyric acid. The enzymatic resolution of N-acetyl-erythro- and -threo-β-hydroxy-Dl-norleucine is also described.
The Oxidation of 1,3-Butadienes with Nitric Acid into 2,5-Dihydrofurans
Authors: Toda Fumio , Todo Eishiro
Published: July 2006

The oxidation of 3,4-bis(diphenylmethylene)-succinic anhydride (I), -1-benzylsuccinimide (VI), and -γ-butyrolactone (VIII) with nitric acid afforded the corresponding 2,5-dihydrofuran derivatives, III, VII, and IX respectively. The same oxidation of 3,4-bis(diphenylmethylene)cyclobutane-1,2-dione (XI) afforded 3,4-bis(diphenylhydroxymethyl)cyclobut-3-ene-1,2-dione (XIII), probably via the bicyclic cyclobutenedione intermediate (XII).
An ENDOR Study of the Relaxation Behavior of the Nuclei in Several Semiquinone Anion Radicals
Authors: Kotake Yashige , Kuwata Keiji
Published: July 2006

The ENDOR intensities of several semiquinone anion radicals were measured at various temperatures. The optimum temperature for the ENDOR intensity of protons in a radical was interpreted on the basis of their characteristic ways of relaxation. The electron nuclear dipolar (END) mechanism could be applied very well in most cases. However, in the case of protons whose END terms are very small this interaction might not explain the optimum temperature. Possible substitute mechanisms were discussed.
Dielectric Relaxation and Molecular Structure. IX. Dielectric Behavior of 1-Propanol and 1-Butanol in a Variety of Solvents
Authors: Koshii Taro , Arie Eiji , Nakamura Masahiko , Takahashi Hiroaki , Higasi Keniti
Published: July 2006

The dielectric constants and losses of 1-propanol and its mixtures with benzene, chlorobenzene, 1,4-dioxane or pyridine, and 1-butanol and its mixtures with benzene or pyridine have been measured in the frequency range of 0.35–2.1 GHz at 25.0 °C. Concentrations of alcohols are 1–0.6 mol fraction of the mixtures. Densities and refractive indices have also been determined. The dielectric data were used to calculate the relaxation times of the alcohols. The Cole-Cole plots for these systems showed Debye-type semicircles in lower frequencies where the principal relaxation of alcohols dominates. Deviations from the semicircle, however, have been observed in the region of upper frequencies, where the second dispersion of alcohol, the dispersion of solvent itself and of hydrogen-bonded species between alcohol and solvent may occur. The principal relaxation times of alcohols calculated from the data of lower frequencies change with concentration in two different manners by solvents, and this difference is due to whether the solvent has hydrogen-bonding capacity or not, and does not depend upon the dielectric constant and/or the polarity of the solvent.
The Reaction of Bis (2-pyridinecarbonitrile) copper(II) Chloride with Methanol and Various Amines
Authors: Suzuki Shinnichiro , Nakahara Masayoshi , Watanabe Ken-ichi
Published: July 2006

On treatment of bis(2-pyridinecarbonitrile)copper(II) chloride with various amines in methanol, the alkoxylation of the nitrile group in the complex took place; in some cases, the alkoxylation and the ligand substitution of the complex occurred at the same time. The reaction products were classified into three types depending on the amines used; two of the types consisted of new complexes. The complexes of CuCl2(MeOpy)(Amine) (MeOpy: O-methylpyridine-2-carboximidate), were obtained on the addition of ammonia, methylamine, dimethylamine, ethylamine, benzylamine, or piperidine to a methanol solution of bis(2-pyridinecarbonitrile)copper(II) chloride. On the other hand, the addition of trimethylamine, diethylamine, or triethylamine afforded the complex of CuCl2(MeOpy)2. These types of complexes were not obtained by the use of aniline or pyridine; but the previously known complex, CuCl2(MeOpy), was obatined in this case. It has been assumed that the formation of the three types of complexes is essentially the result of both the basicities and the steric factors of the amines.
Infrared Spectra of Nitrosylplatinum (14NO and 15NO) Complexes
Authors: Miki Eiichi , Mizumachi Kunihiko , Ishimori Tatsujiro , Okuno Hisateru
Published: July 2006

The 15NO-complexes for trans-[PtCl(NH3)4(NO)]Cl2, trans-K2[PtCl(NO2)4(NO)] and M2[PtX5(NO)] (M=K and Cs, X=Cl and Br) were prepared. The effect of 15N-substitution on infrared spectra indicated that the weak absorption band at ca. 290 cm−1 is assigned to the Pt-(NO) stretching vibration and the absorptoin band in the region 530–570 cm−1 to the Pt-(NO) bending vibration.
Proton Magnetic Resonance Spectra of Metal Ammine Complexes. I. Cobalt(III) Pentammine Series
Authors: Yoneda Hayami , Nakashima Yoshiaki
Published: July 2006

The proton magnetic resonance spectra have been measured in dimethylsulfoxide on some cobalt(III) complexes of the type [CoX(NH3)5]. Ammine protons show two peaks, except in a complex with X=NO2−. The major peak, due to cis NH3, appears downfields and the minor one, due to trans NH3, upfields as compared with the shift in [Co(NH3)6]3+. In the case of X=CN−, the shift pattern is reversed. For [Co(NO2)(NH3)5]2+, the spectrum is a single peak. This chemical shift behavior is explained by a simple model based on Ramsay’s theory for chemical shift. It is concluded that the behavior arises primarily from paramagnetic anisotropy of the central cobalt (III) ion. The model used in this work is shown to be applicable also to the assignment of the PMR spectra for complexes of the types cis-[CoX2(NH3)4] and cis-[CoX2(en)2].
Implication of Diazonium Cations as Intermediates in the Photorearrangement of Azoxybenzenes
Authors: Bunce Nigel James
Published: July 2006

Photolysis of azoxybenzene and 2,2′-azoxytoluene in the presence of 2-naphthol gives, in addition to o-hydroxyazocompounds, 1-arylazo-2-naphthols, sometimes as the major products. This implies that cleavage into diazonium ions may sometimes be a major pathway in the irradiation of aromatic azoxycompounds. A mechanism is proposed to account for the formation of azonaphthols as well as the various side products that have previously been obtained from these reactions.
Estimation of the Structures and Electronic States of Radicals Using the INDO–SCF MO Method. I. Alkoxyl Radicals
Authors: Ohkubo Katsutoshi , Kitagawa Futoshi
Published: July 2006

The most energetically stable alkoxyl radicals take the following configuration: r(C–O)=1.36 Å, r(C–H)=1.12 Å, and ∠OCH=109°28′ for CH3O·, and r(C–O)=1.36 Å, r(C–C)=1.47 Å, and ∠OCC=108° for C2H5O·. The pseudo π orbital is observed in the C–O bond.
Benzo[h]quinolin-10-yl-N Iridium(III) Complexes
Authors: Nonoyama Matsuo
Published: July 2006

Benzo[h]quinoline(bhqH) is metallated with iridium(III) to give [Ir(bhq)2Cl]2 in which bhq is coordinated at 1-N and 10-C atoms. This complex reacts with a ligand(L) such as tri-n-butylphosphine and diethylsulfide to yield [Ir(bhq)2ClL].
The Reaction of Substituted Tropones with Diphenylketene
Authors: Asao Toyonobu , Morita Noboru , Iwagame Nobuo
Published: July 2006

The reaction of 2-methoxytropone and diphenylketene afforded (2+8)cycloadduct and 1-methoxy-8,8-diphenylheptafulvene which must be formed by the decarboxylation of the initially-formed (2+2)cycloadduct. 2-Dimethylaminotropone also gave the heptafulvene derivative. However, 2-chloro-, 2-cyano-, and 2,5-dimethoxytropone yielded only (2+8)cycloadducts.
The Reaction of Isocyanates with Carboxylic Acids and Thiocarboxylic Acids
Authors: Motoki Shinichi , Saito Takao , Kagami Hiroaki
Published: July 2006

Thiocarboxylic acids reacted with isocyanates or acyl isocyanates to give the stable addition products. However, similar products obtained from benzoic acid and acyl isocyanates dissociated into their components in solution.
Association Involving Optically Active Ions. III. Pfeiffer Effect in Tris(phenanthroline)-zinc(II) or –nickel(II) –Alkaloid Systems
Authors: Ogino Kazuko , Kumagai Tokue
Published: July 2006

Pfeiffer effect was studied in aqueous solutions containing tris(phenanthroline)metal(II) (metal=zinc or nickel) complexes and various alkaloids. The results were interpreted quantitatively from the viewpoint of stereoselective association and the resulting equilibrium shift. The contribution of π-π interaction between the complex and the alkaloid conjugate systems to the stereoselective association is suggested. NMR data were found to be consistent with the π-π interaction. Relation between the sign of the Pfeiffer rotation and the absolute configuration of the complex is presumed.
2,3,5,6-Tetra-aryl-1,2,4,5-tetra-azapentalenes. A New Heteroaromatic System
Authors: Matsumoto Akira , Lee Joung Hee , Yoshida Masayuki , Simamura Osamu
Published: July 2006

2,3,5,6-Tetra-aryl-1,2,4,5-tetra-azapentalenes (II) have been prepared by the dimerization of arylazoethynylarenes (I). The properties of the new ring system are discussed on the basis of their reactivities.
Mechanistic Studies on the Photooxidation of Chlorpromazine in Water and Ethanol
Authors: Iwaoka Teiki , Kondo Michio
Published: July 2006

It has been established that chlorpromazine undergoes photooxidation via its cation radical, yielding chlorpromazine 5-sulfoxide as an ultimate photoproduct. Molecular oxygen has been found indispensable not only for the formation of chlorpromazine cation radical but also for the formation of the sulfoxide from the radical. Oxygen atom in the sulfoxide originates from the atmospheric oxygen and not from water, which was ascertained by both tracer experiment and kinetic analysis. It was concluded that phenazathionium ion is not involved in the reaction. The possibility of singlet oxygen participation in the photooxidation was also ruled out. An intermediate, which is formed from the cation radical, was found as a precursor of the sulfoxide and was tentatively assigned as a peroxyl type radical.
Reaction of Ethyl α,α-Dichloroacetoacetate with Aldehydes
Authors: Takeda Akira , Tsuboi Sadao , Nakashima Isao
Published: July 2006

Ethyl α,α-dichloroacetoacetate reacted with aldehydes in the presence of sodium ethoxide to give α-chloropyruvate and/or α-chloroglycidate. 2,5-Bis(1′-chloroalkylidene)-1,4-cyclohcxanedione (4) was obtained as a by-product in a low yield.
The Cyclic Trimerization of Isocyanates by Organic Tin(II) Compounds Containing Sn–O–C Bonds
Authors: Wakeshima Ikuko , Suzuki Hiroshi , Kijima Ichiro
Published: July 2006

Organic tin(II) compounds containing Sn–O–C bonds were found to be effective catalysts for the cyclic trimerization of phenyl and ethyl isocyanate. The cyclic trimerization mechanism is discussed.
Selenium Catalyzed Synthesis of of Carbonates. The Reaction of Alkoxide with Carbon Monoxide and Oxygen in the Presence of Selenium
Authors: Kondo Kiyoshi , Sonoda Noboru , Sakurai Hiroshi
Published: July 2006

A novel selenium catalyzed synthetic reaction of carbonates was investigated. The reaction of alkoxides with carbon monoxide in the presence of stoichiometric amount of selenium gave carbonates in high yields under atmospheric pressure at 20°C in THF. When the resultant reaction solution was made to react continuously with the mixture gas of carbon monoxide and oxygen, catalytic formation of carbonates was achieved. Isolation of Se-alkyl monoselenocarbonate from the reaction mixture by addition of alkyl halide indicated that carboalkoxy sodium selenide might be formed as an intermediate in the course of present reaction. In connection with these reactions, the reaction of carbonyl selenide with sodium alkoxide in alcohol was also studied.
On the Stable Molecular-shapes of CmHm−4 Cata-condensed Nonalternant Hydrocarbons
Authors: Toyota Azumao
Published: July 2006

The energetically most favorable molecular-symmetry groups and geometrical structures of CmHm−4 catacondensed nonalternant hydrocarbons were examined systematically on the basis of the symmetry rule and the semiempirical SCF MO method. The first excitation energies in the fully-symmetrical nuclear arrangements were found to decrease with increasing the number of carbon atoms, showing a tendency to converge to a certain limiting value, ca. 0.8 eV. Molecules larger than a certain critical size (m∼10) were predicted to suffer the second-order Jahn-Teller distortion, exhibiting a double-bond fixation in the peripheral carbon skeleton. Using the most stable geometrical structures obtained, the electronic spectra of these molecules were calculated. Furthermore, the predictions of the stable molecular-shapes in the lowest excited singlet states were briefly mentioned.
Metal Complexes Containing Six-membered Chelate Rings. IV. The Preparation and Structure of Dichlorocobalt(III) Complexes with Tetramines Derived from 2,4-Pentanediamine
Authors: Mizukami Fujio
Published: July 2006

The tetramine ligands, 4,6-dimethyl-3,7-diaza-1,9-nonanediamine (2,3″, 2-tet), 6,8-dimethyl-2,5,9,12-tetraazatridecane (N,N′-Me2-2,3″, 2-tet), and 4,9-dimethyl-5,8-diaza-2,11-dodecanediamine (3″,2,3″-tet), were prepared by using RR- and RS-2,4-pentanediamine as the starting material. Six kinds of trans-dichloro cobalt(III) complexes with these ligands were prepared and characterized. Among these complexes, three kinds of optically active complexes were obtained. The RR-2,4-pentanediamine and RS-2,4-pentanediamine parts in these complexes were considered to take a λ-skew-boat and a chair conformation respectively on the basis of molecular models, PMR, and the absorption and CD spectra.
Valence States of Arsenic and Antimony in Sea Water
Authors: Gohda Shiro
Published: July 2006

A simple and convenient chemical procedure for the determination of As(III), As(V), Sb(III) and Sb(V) by thermal neutron activation analysis is proposed and applied to the study of the valence state of As and Sb in sea water. Immediately after sampling, As(III) and Sb(III) were separated from As(V) and Sb(V) by extracting their diethyldithiocarbamates with chloroform, and then back-extracted into diluted nitric acid. As(V) and Sb(V) in the aqueous phase were collected by thionalide cocrystallization. They were then irradiated for 30 min at a neutron flux of 2×1013 n/(cm2·s), and treated in the same manner as described in the previous report. The As and Sb were determined by gamma-ray spectrometry. Sea water has been found to contain 1.56–2.45 μg As/l and 0.37–0.60 μg Sb/l. 80–97% of arsenic and 70–94% of antimony existed as the pentavelent species, only 5–20% as the trivalent species, and the remainder was probably included in suspended matter.
Analysis of a Magnesium-containing: β-Eucryptite Solid Solution by the Lattice Constant Method and Its Application
Authors: Iwatsuki Masaaki , Tsukada Norio , Fukasawa Tsutomu
Published: July 2006

An X-ray diffraction method has been developed for the determination of the composition of a magnesium-containing β-eucryptite solid solution which consists of a pseudo-ternary system, SiO2–Mg1⁄2AlO2–LiAlO2. Standard samples of the solid solution within the range of 60–75 mol% SiO2 and 0–15 mol% Mg1⁄2AlO2 were prepared from high-purity materials by the “glass-crystallization” technique. The diffraction angles of the (206) and (212) planes were measured from the center of gravity of the profile recorded on a chart by a counter diffractometer. After having been corrected for various systematic errors, both angles were used for the calculation of the lattice constants. It was found that Mg1⁄2AlO2 and LiAlO2 contributed similarly to a0, but in a different way to c0. The composition of the solid solution in a commercial glass-ceramic could be determined from the correlation between the composition and the lattice constants. The standard deviation of the determination from one measurement was about 0.2–0.4 mol%, and the time required for analysis was about 30 min.
Pyridoxal Catalysis in the α,β-Elimination of S-(p-Substituted phenyl)cysteines
Authors: Murakami Yukito , Kondo Hiroki
Published: July 2006

The pyridoxal-catalyzed α,β-elimination of S-(p-substituted phenyl)cysteines was studied at 50°C and μ=0.10 (KNO3) in 79% (v/v) aqueous acetonitrile in the presence of organic bases of different strength. The rate increased with an increase in basicity. The kinetic solvent isotope effect (kH2O⁄kD2O) of 1.15 is consistent with the reaction mechanism in which the α-proton abstraction occurs by the direct attack of a base on the proton. The elimination rate was insensitive to a change in the electronic nature of a leaving thiophenol, indicating that the α-proton abstraction can be referred to the rate-determining step. The rate showed a considerable dependence on the water content, as reflected on the activation parameters for reactions in 79% (v/v) aqueous acetonitrile as well as in water. The larger destabilization due to water-solvation at the transition state in the aqueous reaction system seems to cause a lower reactivity relative to the organic solvent system. The catalysis of benzene analogs demonstrated that the hydroxyl group adjacent to the aldehyde in pyridoxal plays a major role in the nonenzymatic α,β-elimination reactions.
The Preparation of Aryl Heptafluoroisopropyl Ketones from Aroyl Chlorides and Hexafluoropropene in the Presence of Fluoride Ions
Authors: Ishikawa Nobuo , Shin-ya Seiji
Published: July 2006

Aroyl chlorides and hexafluoropropene in the KF/DMF system gave aryl heptafluoroisopropyl ketones. The substituent effect on the yield was discussed.
The Chemistry of Americium. III. The Coprecipitation of Am(III), Am(V), and Am(VI) by Some Fluorides and Phosphates
Authors: Hara Mitsuo , Suzuki Shin
Published: July 2006

The radiochemical behavior of americium in the coprecipitation process involving a precipitate such as lanthanum, thorium, and ceric fluorides, zirconium, and bismuth phosphates was investigated at the tracer concentrations of americium. All the precipitates except zirconium phosphate completely carried the Am(III), leaving the Am(VI) in the supernatant. The lanthanum and thorium fluorides carried portions of the Am(V) in proportion to the amounts of the metal ion of the carrier added under any given conditions. Then, the analytical conditions were established for determining the distributions of the oxidation states of americium.
The Complexing of the Lithium Ion in Acetonitrile with Other Solvents. Investigation by the Use of a Cation-sensitive Glass Electrode
Authors: Nakamura Toshio
Published: July 2006

The complexing of the lithium ion with other popular solvents has been studied in acetonitrile (AN) using a monovalent cation-sensitive glass electrode. A method similar to that developed to study the complexing of the sodium ion was employed. Mono- and di-solvated species were formed for methanol, pyridine, formamide, methylfomamide, and HMPA. Tri-solvated species were also formed for DMF, DMA, and DMSO. In general, the complexing of the lithium ion with these solvents was more pronounced than that of the sodium ion. The formation constants for the mono-solvated lithium ion were 4.5 for methanol, 5.2 for pyridine, 16 for DMF, 20 for formamide, 25 for methylformamide, 49 for DMSO, 62 for DMA, and 2.1×103 for HMPA. When water was the complexing solvent, the equilibrium potential could not be obtained, probably because of the hydrolysis of the hydrated lithium ion. Prior to these experiments, the cation-sensitive glass electrode was confirmed to respond to the lithium-ion activity in different solvents by comparing its behavior with that of a lithium-amalgam electrode.
Viscosity Behavior of Coacervates of Magnesium and Calcium Highpolyphosphates
Authors: Umegaki Takao , Kanazawa Takafumi
Published: July 2006

The viscosities of magnesium and calcium highpolyphosphate coacervates were measured in the temperature range of 20 to 90 °C. The Andrade’s Equation was an approximate representation for the temperature dependence of viscosities of the coacervates. The activation energies of flow for the highpolyphosphate coacervates of magnesium and calcium were calculated to be about 7 kcal/mol and about 15 kcal/mol, respectively. The extension of the phosphate chains in coacervates was considered to be restricted, and the spinnability of the coacervates was probably originated, not by an elastic network structure, but by high viscosity of the coacervates. The viscosities of the magnesium coacervates decreased with an increase in water content and no remarkable effect of ethyl alcohol on the preparation of the coacervates was found.
Photo-addition Reaction of 1,4-Naphthoquinone with Olefins. Formation of 2:1 Addition Compounds
Authors: Maruyama Kazuhiro , Naruta Yoshinori , Otsuki Tetsuo
Published: July 2006

A novel type of the photo-addition compound, 5,8,13,14-tetraoxo-5,5a,6, 7,7a,8,13,13a,13b,14-decahydropentaphene derivatives (3), consisting of two molecules of 1,4-naphthoquinone and one molecule of an olefin was obtained in the photochemical reaction of 1,4-naphthoquinone with olefins. Its structure was determined from spectral data as well as results obtained from the chemical reactions. Olefins which give this type of photo-addition compound are characterized by their bicyclo-ring systems containing considerable ring strains. The reaction mechanism for formation of the compound was discussed in terms of the ring strains of olefins and the nature of the photo-excited 1,4-naphthoquinone.
Studies of the Crystallization Processes of N-Methylquinolinium TCNQ Ion-radical Salts
Authors: Murakami Mutsuaki , Yoshimura Susumu
Published: July 2006

We studied the crystallization processes of the complex ion-radical salt of 7,7,8,8-tetracyanoquinodimethan (TCNQJ and the N-methylquinolinium cation. A variety of solvents, rates of crystallization, and concentrations of the solution gave three groups of crystals. The crystals in the first group, which were crystallized as black rods, occluded the solvent molecules in the crystals, and their resistivities were in the range of 2.8–26 Ωcm. Those in the second group were crystallized into the form of fine needles or fine powders. Although the TCNQ-to-cation ratios in the salts varied from 1.6 to 2.2, their electrical resistivities were almost all the same (about 1.00 Ωcm), and these crystals were thought to have a metastable crystal structure. The crystals in the third group were crystallized in the form of triclinic prisms, which belonged to a stable crystal of a high resistivity (1100 Ωcm). The appearance of multiple forms is interpreted on the basis of Ostwald’s “Law of Stages” of crystallization and also on the basis of information on the structures of the one-dimensional TCNQ, columns of the other complex ion-radical salts of TCNQ.
Transfer Hydrogenation and Transfer Hydrogenolysis VII. The Mechanism of Hydrogen Transfer from 2-Propanol to Olefins Catalyzed by Dihydridotetrakis(triphenylphosphine)ruthenium(II)
Authors: Imai Hideaki , Nishiguchi Takeshi , Kobayashi Masaki , Fukuzumi Kazuo
Published: July 2006

The dihydride complex, RuH2(PPh3)4, has been found to be an excellent catalyst for the hydrogen transfer from 2-propanol to olefins. For cyclohexene in toluene solution, the rate law at 80°C was:

Rate=\frac0.04[C]_o[D]1+24[P]

where [C]0, [D] and [P] are the concentration of the catalyst, 2-propanol and triphenylphosphine, respectively. It is pressumed that active intermediates of the reaction are not Ru(IV)-species but Ru(0)-species. The rate determining step of the reaction is inferred to be the dehydrogenation of 2-propanol, that is, the hydrogen transfer from the alcohol to Ru(0)-complex to form a hydride complex by oxidative addition.
Sum Rule Consideration of Molecular Photoelectron Spectra. Substituted Ethylenes
Authors: Yamazaki Tomoko , Kimura Katsumi
Published: July 2006

The ionization-energy sum rule previously proposed has been applied to photoelectron spectra of three series of chloro-, bromo-, and methyl-substituted ethylenes C2H4−mXm (m=1 and 2; X=Cl, Br, and CH3) in the He(I) region. The total sums of ionization energies were obtained in the p-type region and the partial sums of ionization energies were interpreted in terms of in-plane and out-of-plane molecular orbitals. The following conclusions have been deduced: (1) The experimental total and partial sums are almost constant in the cis-, trans-, and iso-di-substituted ethylenes. (2) The experimental total and partial sums linearly increase with increasing number of the substituents, the slopes leading to useful informations about orbital energies. (3) Such linear relationships are supported by CNDO/2 and MINDO/2 calculations. (4) The experimental total and partial sums are approximately reproduced in terms of several appropriate Iocalized-molecular-orbital energies based on the photoelectron data of simplest molecules.
Effect of Inorganic Electrolytes on the Cloud Point of Polyoxyethylene Dodecyl Ether
Authors: Tokiwa Fumikatsu , Matsumoto Tadao
Published: July 2006

The cloud points of polyoxyethylene dodecyl ether in the presence of different types of inorganic electrolytes have been determined. The cloud points can be expressed by the empirical equation: (C.P.)s⁄(C.P.)0=1+A\sqrtCs+BCs where (C.P.)0 and are the cloud Points with and without an electrolyte, respectively, Cs is the electrolyte concentration, and A and B are constants.
Photochemistry of N-(4-Dimethylaminobenzylidene)aniline
Authors: Ohta Hiroyuki , Tokumaru Katsumi
Published: July 2006

Irradiation of N-(4-dimethylaminobenzylidene) aniline, contrary to an earlier report, does not give cis-4,4′-bis(dimethylamino)stilbene and azobenzene, however, its triplet state has, exceptionally as an acyclic imine, enogh lifetime at 77 K to exhibit phosphorescence.
Electrical Behavior of Alkali Metal Cation–TCNQ Anion Radical Simple Salts under Very High Pressures.
Authors: Shirotani Ichimin , Onodera Akifumi , Sakai Nobuko
Published: July 2006

The electrical resistance of alkali metal cation–TCNQ anion radical simple salts was measured over the wide pressure range from 0 to 500 kbar at room temperature. The least resistivities for Group A (Li–, Na–, K–, and Rb(I)–TCNQ) are about 0.2–3 Ωcm, while those for Group B (Rb(II)– and Cs–TCNQ) are about 0.06–0.1 Ωcm. The possibility of insulator-metal transition at high pressures is discussed. Above 140–175 kbar the electrical resistance of simple TCNQ salts increases with an increase in the pressure and drifts upward with the time. The solid-phase reaction is observed under very high pressures.
General Anharmonic Force Constants of Carbon Disulfide
Authors: Suzuki Isao
Published: July 2006

Twelve force constants in the general quartic force field of carbon disulfide have been determined by a least-squares method from the available spectroscopic data on four isotopic species of carbon disulfide: 12C32S2, 13C32S2, 12C32S34S, and 13C32S34S. A reasonable set of force constants is obtained together with a set of the third-order parameters λ1, λ2, λ3, and δ which appear in Fermi coupling off-diagonal matrix elements. From the converged set of force constants, l-type doubling constants for a few π-vibrational states are calculated through a direct numerical diagonalization method of vibrational Hamiltonian matrix. They agree well with the observed l-type doubling constants.
Molecular Structure of Trimethylene Sulfide as Studied by Gas Electron Diffraction with Joint Use of Rotational Constants
Authors: Karakida Ken-ichi , Kuchitsu Kozo
Published: July 2006

The molecular structure of trimethylene sulfide (thietane) has been determined by an analysis of electron diffraction intensities combined with the rotational constants determined by microwave spectroscopy by Harris et al.: rg(C–S)=1.847±0.002 Å, rg(C–C)=1.549±0.003 Å, rg(Cα–H)=1.09±0.02 Å, rg(Cβ–H)=1.12±0.04 Å, ∠C–S–C(rav)=76.8±0.3°, ∠H–Cα–H(rav)=112±4°, ∠H–Cβ–H(rav)=114±5° and the dihedral angle, ∠C2SC4–C2C3C4(rav)=26±2°. The uncertainties represent estimated limits of error. The definitions of the geometrical parameters have the usual physical significance except that the normal coordinate representing the large-amplitude ring-puckering motion is extrapolated to its equilibrium position. The conventional formula used in the joint analysis has been modified to account for the large-amplitude vibration.
The Crystal and Molecular Structure of trans-Bis(trimethylphosphine)propynyl-1-(4′-dicyanomethylene-cyclohexa-2′-5′-dien-1-ylidenl-3,3-dicyano-2-methyl-prop-2-en-1-ylplatinum, a Reaction Product of trans-Bis(trimethylphosphine)bis(propynyl)platinum and 7,7,8,8-Tetracyanoquinodimethane
Authors: Onuma Ken-ichi , Kai Yasushi , Yasuoka Noritake , Kasai Nobutami
Published: July 2006

The molecular structure of the title complex has been determined from three-dimensional X-ray diffraction data. The crystal belongs to the monoclinic system, space group P21/c, a=14.934(2), b=8.997(1), c=20.221(3)Å, β=97.44(2)°, Z=4. The molecular structure showed that the tetracyanoquinodimethane (TCNQ) molecule has reacted with one of the propynyl groups of trans-{(PMe3)2Pt(C≡CMe)2} : part of the TCNQ is bonded to the α-carbon atom and the other part to the β-carbon of the propynyl ligand. The platinum atom has a squareplanar geometry; Pt–P=2.302(5) and 2.290(5), Pt–C(C≡CMe3)=2.009(15) and Pt–C(reacted)=2.057(15) Å.
Thermochemical Properties of Lanthanoid-Iron-Perovskite at High Temperatures
Authors: Katsura Takashi , Kitayama Kenzo , Sugihara Tadashi , Kimizuka Noboru
Published: July 2006

The standard Gibbs energy of formation of \barCFeO3(\barC=La, Nd, Sm, Eu, Gd, Tb, and Dy) from metallic iron, \barC2O3, and oxygen has been determined at temperatures from 1473 to 1673 K. Based on the free-energy data, the heat of reaction and the entropy change resulting from the reaction have been calculated. The values of the heat of reaction of LaFeO3, NdFeO3, SmFeO3, EuFeO3, and GdFeO3 (the first group) were identical, −107 kcal/mol, at the present temperature interval. However, the values of the heat of reaction of TbFeO3 and DyFeO3 (the second group) decreased with an increase in the temperature. The entropy change of each reaction in the first group was constant, independent of the temperature, and each value decreased in the sequence from LaFeO3 to GdFeO3. The entropy change of the second group decreased with an increase in the temperature. The change of the standard Gibbs energy was intimately related to the ionic radii of \barC-ions, and the relationship between the Gibbs energy and the tolerance factor has been clarified.
Cobalt(III) Complexes Containing Large Chelate Rings. I. Syntheses and Properties of Bis(ethylenediamine)-1,ω-diaminoalkanecobalt(III) Complexes
Authors: Ogino Hiroshi , Fujita Junnosuke
Published: July 2006

New cobalt (III) complexes, [Co(en)2(H2N(CH2)nNH2)]X3 (n=4, 10, 12 and 14), [Co2(en)4(H2N(CH2)nNH2)2]X6 (n=4, 5, 6, 8, 10 and 12), [Co(en)2(H2N(CH2)4NH3)2]X5 and [CoCl(en)2(H2N(CH2)12NH3)]X3 were isolated from the products of reactions between [CoCl2(en)2]Cl and 1,ω-diaminoalkane in dimethylsulfoxide, with the aid of SP-Sephadex column chromatography. For n=5, 6 and 8, no monomeric [Co(en)2(H2N(CH2)nNH2)]3+ was observed. This result is compatible with instability of the medium size rings in organic compounds. The elution behaviors on Sephadex column and the visible and ultraviolet absorption spectra of the new complexes were also described.
Dry Grinding on a Pigment Mixture. I. The Effect of α-Copper Phthalocyanine as a Lubricant on the Mechanochemical Transformation of Calcium Carbonate
Authors: Kawashima Norimichi , Meguro Kenjiro
Published: July 2006

α-Copper phthalocyanine and calcium carbonate were mixed and ground with a grinder, and then the surface properties of the mixtures were investigated in comparison with the grinding time by means of X-ray diffraction analysis, electron-micrograph observation, and the specific surface area as obtained by the B.E.T. method. In the grinding process, the crystal decays of both α-copper phthalocyanine and calcium carbonate were observed. Particularly, the calcite-aragonite transformation occurred in the case of calcium carbonate. However, the addition of some α-copper phthalocyanine to calcium carbonate interfered with the transformation of calcium carbonate. As a conclusion, it was evident that the surface of calcium carbonate was covered with α-copper phthalocyanine and that the grinding of calcium carbonate was interfered with by the lubricating action of α-copper phthalocyanine.
The Reaction of N-Substituted Carbonimidic Dihalides with Grignard Reagents. The Generation of Alkyl or Aryl Halides from Grignard Reagents
Authors: Tanaka Sakuya , Okano Masaya , Tanimoto Shigeo
Published: July 2006

The reaction of N-alkyl- or N-aryl-carbonimidic dihalides with Grignard reagents afforded α-elimination products, isocyanides, rather than substitution ones. Two kinds of alkyl or aryl halides were produced concomitantly in this reaction: one kind consisted of halides generated from the Grignard reagents used, and the other, of halides the halogens of which had been derived from the dihalides. The ease of formation of these halides was found to decrease in the order: iodide>bromide>chloride, regardless of which substrate served as the source of a halogen atom. A probable reaction mechanism is proposed.
Studies on the Catalytic Properties of Synthetic Zeolite A. V. Site Selectivity of Silver Ion in (Agex, Caex)-A
Authors: Nitta Masahiro , Ogawa Kiyoshi , Aomura Kazuo
Published: July 2006

The X-ray diffraction pattern and the propane-adsorption capacity of (Agex, Caex)-A zeolites were determined as a function of the degree of ion exchange. From the change in diffraction intensity and the molecular sieving effect, it was deduced that Ag+ ion prefers site I to site II.
The C–O Bond Cleavage of Allyl Ethers by Rhodium Compounds
Authors: Wayaku Masami , Kaneda Kiyotomi , Imanaka Toshinobu , Teranishi Shiichiro
Published: July 2006

Allyl ethers were cleaved by rhodium compounds under mild conditions to give aldehydes and hydrocarbons. This reaction can be extended to allyl esters.
Ligand-Ligand Interaction in Tris(2,2′-bipyridyl) and Tris (1,10-phenanthroline) Complexes of Nickel(II)
Authors: Ohno Takeshi , Kato Shunji
Published: July 2006

UV spectra of [Ni(2,2′-bipyridyl)3]Cl2 and [Ni(2,2′-bipyridyl)(H2O)4]Cl2 in the mixed solvent of methanol and water (4:1) were measured at 4.2 K. No difference between the spectra indicates a small splitting (<90 cm−1) between the exciton states extending through the three 2,2′-bipyridyls. Since the UV spectrum of [Ni(1,10-phenanthroline)3]Cl2 has a band with the progression as that of [Ni(1,10-phenanthroline)(H2O)4]SO4, a molecular exciton interaction between the three 1,10-phenanthrolines is not strong.
Photosensitized Oxygenation of Unconjugated Cyclic Dienes
Authors: Horinaka Akio , Nakashima Ruka , Yoshikawa Masaharu , Matsuura Teruo
Published: July 2006

The present investigation was undertaken in order to see whether singlet oxygen-oxidation of unconjugated cyclic dienes having spatially close double bonds causes a particular transannular reaction as previously observed with 1,5-cyclooctadiene which gave 4-hydroxy-5-cyclooctenone. Most cyclic dienes tested underwent normal “ene” reaction to give allylic hydroperoxides. Thus, on dye-sensitized photooxygenation followed by reduction with sulfite, dicyclopentadiene, cis,trans-1,5-cyclodecadiene, trans,trans,trans1,5,9-cyclooctadiene, 1,4-cyclooctadiene, 1,3-cyclooctadiene and germacrone yielded a stereoisomeric mixture of tricyclo[5.2.1.02,6]decan-4,8-diene-3-ols, cis,cis-2,7-cyclodecadienol, a stereoisomeric mixture of two 2,5,9-cyclododecatrienols, 2,4-cyclooctadienol, endo-3,8-peroxide of cyclooctene, and germacra-3,7(11),10(14)-trien-9-ol-6-one(E), respectively. Under similar conditions, norbornadiene, and cis,cis-1,6-cyclodecadiene remained virtually unchanged.
Potentiometric Analysis and Fundamental Technique
Authors: Shigemasa Yoshihiro , Shimao Masayuki , Sakazawa Chikahiro , Matsuura Teruo
Published: July 2006

The formose reaction, the calcium hydroxide-catalyzed condensation of formaldehyde to monosaccharides, was potentiometrically analyzed. The oxidation-reduction potential varied in a characteristic way and gave information of considerable importance. Some appreciable transition points in the oxidation-reduction potential curve showed satisfactorily the occurrence of a phase change such as an induction period and saccharide-forming and saccharide-decomposing stages. With regard to the fundamental operating conditions, vigorous stirring and an increase in the dissolved oxygen elongated the induction period. Furthermore, the latter diminished the yield of saccharide under the lower limit of the critical range of the calcium hydroxide concentration.
Restricted Rotation Involving the Tetrahedral Carbon. XV. Restricted Rotation about a Csp8–Csp2 Bond in 9-Aryltriptycene Derivatives
Authors: Nakamura Mikio , Oki Michinori
Published: July 2006

A series of 9-aryltriptycene derivatives have been prepared and their internal rotation about the CAr–C9 bond has been examined by DNMR technique. The PMR behavior of these compounds is best interpreted by assuming a back and forth rotation rather than a full rotation. The barriers to rotation of compounds with one substituted benzo group have been found to be in the range 13–15 kcal/mol, whereas those with two substituted benzo bridges are lower than 9 kcal/mol. The low barrier of these compounds relative to 9-alkyltriptycenes is attributed to the rise in energy of the ground state. The stable conformation of the 9-aryltriptycenes is also discussed.
The Effect of the pH on the Adsorption of an Ampholytic Surfactant, N-Dodecyl-β-alanine, at the Aqueous Surface
Authors: Nakamura Akio , Tajima Kazuo , Sasaki Tsunetaka
Published: July 2006

The effect of the pH on the adsorption of an ampholytic surfactant, N-dodecyl-β-alanine (NDA), at the nitrogen/solution interface was studied by the radiotracer method, using a tritiated compound. The saturated amount of NDA adsorption was found to depend on the pH of the bulk solution; it shows a flat maximum in the isoelectric region from pH 4 to 10, and decreases distinctly on the both acid and alkaline sides. The Gibbs adsorption isotherm for an aqueous solution of the ampholytic surfactant was derived. Using this relation, the amount of adsorption in the pH range from 2 to 6 was calculated from the surface tension vs. concentration and the surface tension vs. pH relations observed for the NDA solution. The calculated values were in good agreement with those obtained by the radiotracer method. The degree of dissociation of the adsorbed monolayer was estimated from the pH dependence of NDA and the chloride ion adsorption.
The Intramolecular Hydrogen Bonding in o-Hydroxybenzyl Alcohol
Authors: Mori Nobuo , Morioka Kenzo
Published: July 2006

IR and PMR spectral investigations showed that o-hydroxybenzyl alcohol in a dilute solution in CCl4 existed predominantly in two internally bonded forms, A and B, and probably also in C.
A Convenient Synthesis of Substituted Pyrocatechols
Authors: Nishizawa Kyoko , Satoh J Yasuo
Published: July 2006

It was found that substituted pyrocatechol derivatives were formed by the reaction of polychlorinated cyclohexane-1,2-diones with lithium carbonate in DMF.
A Convenient Synthesis of α-Bromophenylacetic Acid from Benzaldehyde Using Methyl (Methylthio) methyl Sulfoxide
Authors: Ogura Katsuyuki , Furukawa Shigeko , Tsuchihashi Gen-ichi
Published: July 2006

1-Methylsulfmyl-1-(methylthio)-2-phenylethylene (2a) and 1-methylsulfinyl-1-(methylthio)-2-(p-chlorophenyl)ethylene (2b) reacted with bromine in various solvents to give α-bromophenylacetic acid derivatives. It should be noted that α-bromophenylacetic acid and α-bromo(p-chlorophenyl) acetic acid were mainly obtained by the reaction of bromine with 2a and 2b, respectively, in acetic acid.
Lifetimes of Electrons in Irradiated Liquid Alkanes
Authors: Fueki Kenji
Published: July 2006

A calculation has been made of lifetimes of electrons in irradiated liquid alkanes on the basis of the lifetime distribution function for the geminate electrons derived from the exponential distribution function for electron ranges. The results show that the intrinsic electron lifetimes correlate with the electron mobilities and most of the geminate electrons recombine within 1 ns in the alkanes at room temperature. A consideration is given to the effect of pulse duration time on the apparent electron lifetime and the observable yield of electrons in n-hexane.