bluuebunny/crossref_metadata_2025 huggingface dataset:
Stereoselectivity in Mixed Tris-type Complexes of Cobalt(III) with l-Proline and l- or d-Aspartic Acid
Authors: Matsuda Toshitsugu , Shibata Muraji
Published: July 2006

Mixed complexes with l-proline and l- or d-aspartic acid, [Co(l-pro)3−n(l-(or d-)asp)n]n− (n=1,2), have been prepared and separated into a number of stereoisomers by means of ion-exchange chromatography. The structures of the isomers have been characterized by various spectral data. As to the [Co(L-pro)(d-asp)2]2− and [Co(l-pro)2(d-asp)]− complexes, all of three possible mer-isomers have been isolated in their Δ-forms. The formation ratios among the isomeric species in the reaction system have been estimated spectrophotometrically. Marked differences in stereoselectivity have been found between the l-aspartato complexes and the corresponding d-aspartato complexes. These selectivities have been qualitatively explained in terms of the interaction between the dangling β-carboxylate group in a chelated aspartate ion and the adjacent ligand.
A-Substituted 5β-Steroids. V. Syntheses and Some Reactions of 1-Oxygenated 5β-Cholestanes
Authors: Satoh J Yasuo , Misawa Katsumi , Takahashi T Tomoyoshi , Hirose Masakatsu , Horiuchi C Akira , Tsujii Shin-ichiro , Hagitani Akira
Published: July 2006

1-Oxygenated 5β-cholestanes were synthesized in good yield from 3-oxygenated 5β-cholestane through 5β-cholest-1-en-3-one. The reaction of 1β,2β-epoxy-5β-cholestan-3-one with hydrogen halide occurs with a normal ring cleavage resulting in the formation of 2-halo-5β-cholest-1-en-3-one. The reaction of 1β-hydroxy-5β-cholest-2-ene with chromium trioxide gave the allylic rearrangement product, 5β-cholest-1-en-3-one. The oxidative acetylation and bromination of 5β-cholestan-1-one is described.
The Carbonylation of Alcohols Catalyzed by Cu(I) Carbonyl
Authors: Souma Yoshie , Sano Hiroshi
Published: July 2006

In conc. H2SO4 containing the Cu(I) compound, alcohols react with carbon monoxide at room temperature and atmospheric pressure to produce tert-carboxylic acids in high yields. Primary carboxylic acid is not formed. It is assumed that the unstable Cu(I) tricarbonyl ion, Cu(CO)3+, is transiently formed in conc. H2SO4. An amount of the Cu(I) compound as small as 0.2 mol/1 is sufficient. The catalyst is effective at H2SO4 concentrations above 80%. The reaction rate decreases with a decrease in the H2SO4 concentration. At H2SO4 concentrations of less than 80%, no carboxylic acids are obtained.
Charge-transfer and Proton-transfer in the Formation of Molecular Complexes. VII. Complex Isomerism in Several Anilinium Alkyl-substitiited Picrates
Authors: Inoue Nobuaki , Matsunaga Yoshio
Published: July 2006

o-Chloroanilinium and o-bromoanilinium methylpicrates are obtainable not only as yellow-colored salts, but also as unstable, monotropic reddish-orange forms. Spectroscopic studies have revealed that the latter are charge-transfer complexes composed of the aniline molecule acting as an electron-donor and the acid molecule acting as an acceptor. Similar monotropic forms have been found in combinations of dimethylpicric acid with o-iodo-aniline, o-bromoaniline, and N,N-dimethylamino-p-benzaldehyde.
Small-angle Electron Scattering by Gases. CS2 and CCl4
Authors: Nagashima Makoto , Konaka Shigehiro , Iijima Takao , Kimura Masao
Published: July 2006

The small-angle scattering intensity of 40 keV electrons by CS2 and CCl4 molecules has been measured by the use of a counting unit. The experimental intensities have been compared with the theoretical values for the independent-atom-model, and an analysis of the comparison has shown the consistency of the present results with Tavard’s energy relation. The difference intensity, Δσ(s), of CCl4 has shown oscillatory behavior resulting from the distortion of charge distribution due to chemical-bond formation.
Radiotracer Studies on Adsorption of Surface Active Substance at Aqueous Surface. V. Effects of Additives on the Adsorption of Tritiated Nonionic Surfactant
Authors: Tajima Kazuo , Iwahashi Makio
Published: July 2006

The effects of additives on the adsorption of tritiated hexaoxyethylene dodecyl monoether (TD(EO)6) at the air-solution interfaces have been determined at 30 °C. The salting-out effect has been found to follow the Hofmeister series for the sodium salts of various anions, whereas a constant amount has been found for the adsorption increase due to the addition of various chlorides varying with the type of cation. The salting-in effect is observed for denaturants such as urea, urea nitrate and guanidine nitrate, but not for di- and tri-ethylene glycols.
Electroluminescence in Pentacene Doped Anthracene Crystals
Authors: Wakayama Nobuko I , Wakayama Nobuyuki , Williams D F
Published: July 2006

The recombination radiation spectrum and its transient behavior were measured on a pentacene doped anthracene crystal. The recombination radiation spectrum was more sensitive to chemical or physical impurities than optically sensitized fluorescence spectrum. The intensity of both anthracene and pentacene emission was approximately proportional to the current. Anthracene or pentacene emission was found to consist of three components differing by their decay times; component 1 (decay time <10−5s), components 2,3 (decay times in the millisecond region, τ2<τ3). The component 1 was due to singlet excitons generated directly by carrier recombination. The component 2, the decay time of which was 2–3 ms, was due to triplet exciton annihilation, for its decay time was not affected by a reverse bias voltage and was equal to one half of the observed phosphorescence lifetime. The component 3, which was removed by a reverse bias voltage, was due to detrapped-trapped carrier recombination. Pentacene chemical impurity works as carrier traps or tirplet exciton traps. Anthracene lattice defects work as carrier traps. The SCLC measurement showed the existence of an electron discrete trap introduced by pentacene and electron and hole exponential traps. The present experimental results showed het importance of traps in the recombination process in a mixed crystal.
Vibrational Spectra and Molecular Conformations of Dialkyl Disulfides
Authors: Sugeta Hiromu , Go Akikatsu , Miyazawa Tatsuo
Published: July 2006

The infrared and Raman spectra of several dialkyl disulfides were measured and their conformations were discussed in relation with the characteristic S–S and C–S stretching vibrations. The infrared spectra in the solid state and the temperature dependence of Raman spectra were measured for ethyl methyl disulfide and diethyl disulfide. For ethyl methyl disulfide, the gauche-gauche isomer was more stable than the trans-gauche isomer by about 0.9 kcal/mol while for diethyl disulfide the gauche-gauche-gauche isomer was more stable than the trans-gauche-gauche isomer by about 0.6 kcal/mol in the liquid state. Only the gauche-gauche form for ethyl methyl disulfide and only the gauche-gauche-gauche form for diethyl disulfide were observed in the solid state.
The Isomerism of Metal Complexes Containing Multidentate Ligands. IV. The Cobalt(III) Complex of Linear Pentaethylenehexamine
Authors: Yoshikawa Yuzo , Yamasaki Kazuo
Published: July 2006

The cobalt(III) complex incorporating sexidentate linear pentaethylenehexamine(1,14-diamino-3,6,9,12-tetraazatetradecane) as the ligand was prepared by the reaction of the ligand with [CoBr(NH3)5]Br2 at room temperature in the presence of active charcoal. The resulting solution was subjected to column chromatography on SP-Sephadex, geometrical and optical isomers with four different configurations were then separated and characterized by their electronic and infrared absorption, circular dichroism, and PMR spectra. They have the chemical composition of [Co(C10H28N6)]Cl3·nH2O, n being 1.5–3.
The Photolysis of 3,3-Pentamethyleneoxaziridine
Authors: Kobayashi Yoshinari
Published: July 2006

The ultraviolet irradiation of 3,3-pentamethyleneoxaziridine (1) gave two classes of photo-products: (a) cyclohexanol and n-capronamide, the formation of which proceeds preferentially through the excited triplet state of 1, and (b) ε-caprolactam, dicyclohexylideneazine, and cyclohexanone, which are mainly furnished via the singlet state of 1. The correlation of the selectivity of (a)-class products with the triplet-state energy of the quenchers used made it possible to estimate that the lowest triplet energy of 1 was approximately 60 kcal/mol. The sensitized photolysis of 1 using sensitizers, the triplet-state energy of which was more than nearly 60 kcal/mol, gave n-capronamide predominantly. The photolytic decomposition rate of 1 was compared with those of 2-methyl-3,3-tetramethyleneoxaziridine (2), 2-methyl-3,3-pentamethyleneoxaziridine (3), and cyclohexanone oxime. The mechanism of the photolysis of 1, including homolytic N–O bond rupture, was also discussed.
The Viscosities of Aqueous Sodium Alkylsulfate and Alkyltrimethylammonium Bromide Solutions
Authors: Tanaka Mitsuru , Kaneshina Shoji , Nishimoto Wataru , Takabatake Hiroyuki
Published: July 2006

The viscosities of aqueous solutions of sodium alkylsulfate and alkyltrimethylammonium bromide have been measured at various temperatures from 5 to 55°C. The viscosity data have been interpreted in terms of the Jones-Dole equation, and the viscosity B coefficients for the alkylsulfate and alkyltrimethylammonium ions at various temperatures have been calculated. The B values for these ions are all positive; they decrease with an increase in the temperature and increase linearly with an increase in the alkyl-chain length. The increment of B is found to be 0.076/–CH2– at 25°C. The energy and the entropy of activation for the viscous flow at 25°C have been calculated for these ions; they increase with an increase in the alkyl-chain length. This behavior of the B coefficient, and the energy and the entropy of activation for the viscous flow may be interpreted by saying that the longer-chain ions promote the hydrogen-bond structure of water around the hydrocarbon chain of these ions, while shorter-chain ions, e.g., ethylsulfate and ethyltrimethylammonium ions, behave instead as structure breakers because of the predominance of the disordering effect on the water around the ionic head. The viscosities of micellar solutions have also been measured. The volume of micelles as a hydrodynamic moving unit in solution has been estimated.
The Primary Photochemical Process of Isoquinoline N-Oxide in Hydroxylic Solvents
Authors: Ono Isao , Hata Norisuke
Published: July 2006

In order to deduce the nature of the reactive state of the photochemical isomerization of isoquinoline N-oxide in methanol or water, investigations by means of steady-light irradiation and flash spectroscopy were carried out under various conditions. Transient absorptions were observed in the spectral region between 360 nm and 600 nm; they were identified as being due to a T–T transition of isoquinoline N-oxide. Experiments on both the measurements of the quantum yields and the decay kinetics of the transient species under different conditions revealed that the excited singlet state of isoquinoline N-oxide was responsible for the isomerization. The photochemical behavior in aqueous solutions at various pH values was also examined; consequently, the photochemical isomerization was found to be independent of the hydrogen ions, although it did not occur in a strongly acidic solution (pH<3.0) because of the formation of the protonated N-oxide. The biacetyl-photosensitization for isoquinoline N-oxide led to the dissociation of the N–O bond instead of to isomerization.
Polarographic Studies of the Anodic Oxidation of Mercury. II. The Anodic Adsorption Wave of Ethylamine in N,N-Dimethylformamide
Authors: Matsui Yoshihisa , Date Yoshio
Published: July 2006

Ethylamine at concentrations lower than 0.5 him in N,N-dimethylformamide gives a diffusion-controlled anodic wave due to the reversible oxidation of the mercury to a 1:2 complex of mercury(II) with the amine. At higher concentrations, another anodic wave appears at a potential less positive than the main wave; this has been attributed to the adsorption of the oxidation product on the mercury electrode. The adsorption prewave was analyzed on the basis of Brdicka’s theory, in which the Langmurian adsorption was assumed. It was shown that the nature of the prewave can be well interpreted on the additional assumption that the adsorption coefficient of the adsorbed complex decreases exponentially as the electrode potential becomes more positive.
Mechanisms and Kinetics of the Decomposition of Trioxalatocobaltate(III) in Aqueous Sulfuric Acid
Authors: Kimura Masaru , Sato Toshiro
Published: July 2006

The kinetics of the thermal decomposition of the trioxalatocobaltate(III) complex were studied in a sulfuric acid solution in the absence and in the presence of oxygen from 25 to 40°C. The decomposition of trioxalatocobaltate(III) was described by the equation: -d[Co(C2O4)33−]/dt=(k1+k2[H+])[Co(C2O4)33−]. The values of k1 and k2 were 6×10−6 sec−1 and 1.8×10−5 M−1 sec−1 respectively at 25°C. The values of the activation enthalpy change, ΔH1\eweq and ΔH2\eweq, were 29.7 and 30.0 kcal mol−1 respectively. The values of the activation entropy change, ΔS1\eweq and ΔS2\eweq, were 17.4 and 20.9 eu respectively at 40°C. Although hydrogen peroxide was formed in the presence of oxygen, and although a white precipitate of the polymerized products of acrylonitrile was found in the presence of acrylonitrile, neither oxygen nor acrylonitrile affected the kinetics of the decomposition of trioxalatocobaltate(III). The decomposition of peroxodisulfate was induced by the decompossition of trioxalatocobaltate(III). However, the rate of the decomposition of trioxalatocobaltate(III) was not affected by peroxodisulfate. On the other hand, both copper(II) and iron(III) ions were accelerators of the decompsition of trioxalatocobaltate(III). An anion radical of CO2− was predicted as an intermediate. The reaction mechanisms will be presented to account for these facts.
Preparation and Characterization of Cobalt(III) Complexes with N-Carboxylate Derivatives of l-Prolinate
Authors: Okamoto Ken-ichi , Hidaka Jinsai , Shimura Yoichi
Published: July 2006

Four cobalt(III) complex anions, bis(l-prolinate-N-monopropionato)-, (l-prolinate-N-monoacetato)(imino-diacetato)-, (l-prolinate-N-monopropionato)(iminodiacetato)- and (l-prolinate-N-monoacetato)(l-prolinate-N-monopropionato)cobaltate(III) were synthesized. They were isolated as sodium or potassium salts by ion-exchange column chromatography. These complexes were characterized on the basis of their absorption and circular dichroism spectra in the visible and near ultraviolet regions. All the complexes obtained in solid state have trans(N)-RR or trans(N)-R. configuration. Two geometrical isomers were obtained for (l-prolinate-N-monopropionato)triamminecobalt(III) complexes.
Kinetics and Mechanism of Formation of Monothiocyanato and Mononitrilotriacetato Complexes of Iron(III)
Authors: Funahashi Shigenobu , Adachi Shoji , Tanaka Motoharu
Published: July 2006

Kinetics of the formation of monothiocyanato and mononitrilotriacetato complexes of iron(III) in aqueous solution have been studed by using a stopped-flow technique:

Fe3++SGN−\oversetk1\undersetk−1\ightleftharpoonsFeNCS2+

FeOH2++SCN−\oversetk2\undersetk−2\ightleftharpoonsFeNCS2++OH−

FeOH2++H2nta−\oversetk→Fe(nta)+H+

Rate constants at 25°C and μ=0.5 (NaClO4) are as follows: k=90 M−1 sec−1, k−1=1.6 sec−1, k2=5.1×103M−1sec−1, k−2=10×1013 M−1 sec−1, k=1.0×105 M−1 sec−1. Some discussions are made on the effect of hydroxide ion on the complex formation reactions.
The Cobalt Carbonyl-catalyzed Hydroesterification of Butadiene with Carbon Monoxide and Methanol
Authors: Matsuda Akio
Published: July 2006

The cobalt carbonyl-catalyzed hydromethoxycarbonylation of butadiene is studied. The reaction proceeds in the presence of a pyridine base to give methyl 3-pentenoate. Isoquinoline is found to be a better solvent for the production of methyl 3-pentenoate than pyridine, not only because the yield of the ester is somewhat higher in the presence of isoquinoline than in the presence of pyridine, but also because it is far less volatile than pyridine, so that the product can be easily separated from the solvent and the catalyst by distillation. Also, the hydromethoxycarbonylation of methyl 3-pentenoate under somewhat different conditions is found to give a good yield of dimethyl adipate. The hydroformylation of methyl 3-pentenoate is studied as well. The effect of such a solvent as THF, benzene, and acetonitrile in increasing the selectivity to methyl 5-formylpentanoate is found to increase in this order: acetonitrile<benzene<THF.
The Reaction of β-Amino α,β-Unsaturated Esters with Amines
Authors: Yokoyama Yasukazu , Tai Akira
Published: July 2006

The reactions between amines and 1,4-bis(ethoxycarbonyl)-2,5-bis(alkyl- or arylamino)-1-4-cyclohexadiene(I) and its analogs are studied. The main products are N,N′-disubstituted urea(II) and 1,4-bis(alkyl- or arylamino)-1,4-cyclohexadiene(V) instead of the expected carboxamide. The presence of small amounts of ethyl N-substituted carbamate (III) in the products leads to the conclusion that the reaction proceeds through two successive steps: the nucleophilic attack by an amine upon a carbonyl carbon atom of the ethoxycarbonyl group, with a cleavage of a carbon-carbon bond to give III and V, and the amidation of III in situ, giving II. The rate of the second step is much faster than that of the first step. The formation of II occurs in the compounds with a β-amino α,β-unsaturated carbonyl group.
Solvent Effect on the Free Radical Phenylation with Phenylazotriphenylmethane
Authors: Kobayashi Michio , Minato Hiroshi , Watanabe Nobuko
Published: July 2006

The effect of solvent on free radical phenylation of arenes was studied by using phenylazotriphenylmethane as the source of phenyl radical. Mixtures of two arenes were phenylated in a solvent (CCl4, CH3CN, DMSO, or cyclohexane), and isomer distributions of diaryls produced were determined. The effect of salts (NaNO2, KNO2, NaClO4) was also studied in DMSO. Both the solvent effect and salt effect suggest the contribution of polar structure in the transition states for the formation of phenylcyclohexadienyl radicals.
Dimerization of Isoprene by Palladium-Diphosphine Complex Catalyst
Authors: Takahashi Kuniyuki , Hata Go , Miyake Akihisa
Published: July 2006

Oligomerization of isoprene catalyzed by the PdBr2(Ph2PCH2CH2PPh2)2-PhONa catalyst was studied. The catalyst activity was greatly enhanced by the addition of phenol. Five linear dimers were identified. Distribution of the isomeric dimers was remarkably affected by the molar ratio of phenol to isoprene. The reaction in the presence of a small amount of phenol (phenol/isoprene=1/30) gave 2,7-dimethyl-1,trans-3,7-octatriene derived from a tail-to-tail dimerization almost selectively, while the addition of a large amount of phenol (phenol/isoprene=1/1.5) afforded head-to-head dimers (2-vinyl-5-methyl-1,6-heptadiene and 3,6-dimethyl-1,cis-3,7-octatriene) as main dimers (more than 40% of all the dimers). In a 1:3 ratio of phenol to isoprene the dimers consisted of mainly 2,6-dimethyl-1,trans-3,7-octatriene derived from a head-to-tail dimerization.
Charge-transfer and Proton-transfer in the Formation of Molecular Complexes. IV. Picric Acid Complexes with Benzidine and Its Derivatives
Authors: Saito Gunzi , Matsunaga Yoshio
Published: July 2006

The preparation of picric acid complexes with benzidine, o-tolidine, 3,3′-dichloro-o-tolidine, 3,3′-dibromo-o-tolidine, o-dianisidine, and N,N,N′,N′-tetramethylbenzidine was attempted in the following three solvents: benzene, chloroform, and ethanol. From benzene and chloroform, 3,3′-dibromo-o-tolidine forms a 1 : 1 complex of the charge-transfer type, but the other five diamines give yellow salts formed by means of proton-transfer. Some complexes prepared in ethanol are of an unfamiliar nature. The spectroscopic examination of the 1 : 1 complexes with o-tolidine, o-dianisidine, and tetramethylbenzidine revealed that a half of the diamine molecule acts as a proton-acceptor, while the other half has a charge-transfer interaction with the picrate ion. The simultaneous operation of charge-transfer and proton-transfer interactions was also demonstrated in the black-colored complex with benzidine of a 2 : 1 composition.
Electronic Structures and Spectra of Pyridinyl Hetero Diradicals. Charge-transfer Interaction between Two Different Radicals
Authors: Itoh Michiya
Published: July 2006

Pyridinyl hetero diradicals, Py(Ac)·(CH2)n Py(Car)·, (in which Py(Ac)· and Py(Car)· are 4-CH3OCC5H4N· and 4-CH3OOCC5H4N·, respectively, and n=3, 4, and 5) were obtained. Equilibrium between the open and closed forms in the hetero diradical n=3 was directly observed by temperature dependence of absorption spectra (−ΔH=5.6 kcal and ΔS=10.5 e.u.). Electronic absorption spectroscopy and SCF–CI molecular orbital calculation reveal that the closed form shows a strong charge-transfer band from Py(Car)· to Py(Ac)· moieties. The electronic structure of the hetero diradical was discussed in relation to the electronic interaction between two different radicals.
Spin Trapping by Use of Nitroso-Compounds. VII. β-Fluorine Splitting Constants in Nitroxides
Authors: Terabe Shigeru , Konaka Ryusei
Published: July 2006

Hyperfine splitting constants of β-fluorine atoms in aryl perfluoroalkyl nitroxides, ArN(Rf)O·, where Ar= 2,4,6-tri-t-butylphenyl, phenyl, pentafluorophenyl, and 2,3,5,6-tetramethylphenyl and Rf=trifluoromethyl, pentafluoroethyl, and heptafluoroisopropyl were explored. The temperature dependence of hyperfine splitting constants was studied in the cases of 2,4,6-tri-t-butylphenyl and pentafluorophenyl nitroxides. In the former nitroxides the conformation of β-fluorine atoms are rigid and dihedral angles between the Cβ–F bonds and pz orbitals are 30 and 0° when perfluoroalkyl groups are ethyl and isopropyl, respectively. The conformational dependence of β-fluorine splitting constants are discussed, and it is concluded that the cos2θ law, aβF=(B0+Bcos2θ)ρπ, is also applicable to β-fluorine splitting constants in a series of nitroxides. The values of B0 and B seem significantly dependent on the compound.
The Synthesis of 3-Amino-3-deoxy-d-allose and Related Substances
Authors: Koto Shinkiti , Kawakatsu Noboru , Zen Shonosuke
Published: July 2006

Starting from methyl 2,4,6-tri-O-benzyl-α-d-glucopyranoside, a facile synthesis of 3-amino-3-deoxy-d-allose was carried out; some new O-benzyl derivatives of 3-amino-3-deoxy-d-allopyranose are also described.
Stereochemical Studies on the Halogenation of Sulfoxides. I. The Chlorination of Cyclic Sulfoxides
Authors: Iriuchijima Shinobu , Ishibashi Mariko , Tsuchihashi Gen-ichi
Published: July 2006

The cyclic sulfoxides, thiane 1-oxide, cis- or trans-4-chlorothiane 1-oxide, and cis- or trans-4-phenylthiane 1-oxide, were chlorinated with t-butyl hypochlorite, sulfuryl chloride, and chlorine in the presence of potassium acetate or pyridine. The stereoformulas of the products, together with those of the isomers having an inverted sulfoxide configuration, were determined by means of the IR and NMR spectral data and the Rf-values in the tlc. Consequently, it has been found that chlorination occurs when the sulfinyl oxygen is equatorial and that chlorine is always introduced at a trans-position to the sulfinyl lone pair to give rise to the cis-products. A mechanism accommodating these results is proposed. The conformation of the substituted thiane 1-oxide rings is also discussed.
The Preparation of 5,8-Quinolinediol and 1,4-Acridinediol Derivatives
Authors: Oguchi Sh\={o}shichi
Published: July 2006

Compounds of 6,7-di X substituted 5,8-quinolinediol (X=COOC2H5; CN; COCH3) have been prepared from diethyl pyridine-2,3-dicarboxylate and the respective active methylene compounds. Similarly, 2,3-di X substituted 1,4-acridinediol (X=COOC2H5) has been prepared.
Lilac Aldehydes
Authors: Wakayama Seiji , Namba Satoshi
Published: July 2006

New odorous aldehydes, diastereomers, have been found in lilac flower oil and named lilac aldehydes. The structure was established to be 2-(1′-formyl)ethyl-5-methyl-5-vinyl tetrahydrofuran. Absolute configurations have also been inferred.
Pyrolysis of Tris (2,3-dibromopropyl) Phosphate and Its Related Compounds
Authors: Okamoto Yoshiki , Kimura Norio , Sakurai Hiroshi
Published: July 2006

The main product obtained by the pyrolysis of halogenated alkyl phosphate was found to be alkyl halide. The phosphoryl group was substituted for the halogen atom, olefins being minor products.
The Crystal Structure of Acridinium Bis(7,7,8,8-Tetracyanoquinodimethanide), ARD+(TCNQ)2− and Some Remarks on the Possibility of a Peierls Distortion of a Linear Chain of TCNQ
Authors: Kobayashi Hayao
Published: July 2006

Crystals of acridinium-TCNQ(ARD(TCNQ)2) are triclinic, space group P\bar1 with a=3.841(2), b=13.018(6), c=18.370(12)Å, α=114.32(5), β=119.31(4), γ=90.57(7)° and Z=1. ARD and TCNQ, are separately stacked to form columns along the a axis. Each ARD column is surrounded by six TCNQ, columns. The orientation of ARD is disordered. Intermolecular distance between adjacent TCNQs is 3.246 Å and that between adjacent ARDs is 3.418 Å. The possibility of a Peierls distortion of TCNQ columns was discussed on the basis of the model of one-dimensional distorted lattice. Calculations of free energy show that alternation of intermolecular spacing disappears at Peierls transition temperature, Tp of about 200 K. For T>Tp, the one-dimensional band is not split (metallic), while it is split below Tp(semiconductive). The specific heat curve shows a peak at about 180 K and the heat of transition is calculated to be about 130 cal/mol.
Some Environmental Effects on the shf Lines in the ESR Spectra of Vanadyl Tetraphenylporphin
Authors: Sato Mitsuo , Kwan Takao
Published: July 2006

The ESR spectra of vanadyl tetraphenylporphin (VOTPP) have been studied in a number of organic matrices, with special attention paid to the resolution of the nitrogen shf lines. The matrices were classified into three groups according to their effects on the resolutions of the vanadium hf lines and of the nitrogen shf lines. In the A-group matrices, the spectra of VOTPP displayed well-resolved hf lines, accompanied by shf splittings; in the B-group matrices, the spectra gave rise to well-resolved hf lines, but without shf splittings, and in the C-group matrices, the hf lines were resolved only poorly. It is suggested that a high dispersion of VOTPP molecules is required for the higher resolution of spectra.
The ESR of the Fast-rotating –CH2 of the Radical Formed by the Photolysis of CH2I2 on Silica Gel
Authors: Shimokoshi Kazuo
Published: July 2006

The electron spin resonance spectra have been measured for the radical formed by the photolysis of methylene iodide adsorbed on silica gel. The spectra were anisotropic and were attributed to the radical of the ≡Si–O–CH2form by an analysis of the hyperfine splittings due to two protons, taking into consideration the photochemical processes on the silica gel surface. From a line-shape analysis of the observed spectrum, the following anisotropic hyperfine interaction parameters for the protons and g-value have been obtained:

A_//=28.5±0.5G, A_⊥=18.8 ±0.5G, g=2.0030±0.0005.

It has been concluded from the analysis of the spectra that the hyperfine structure observed with axially-symmetric tensors is a result of the fast internal rotation of the methylene group of the radical.
The Diazotization of 2-Aminoazulene Derivatives. The Formation of 2-Diazo-2,6-azulenoquinone Derivatives
Authors: Nozoe Tetsuo , Asao Toyonobu , Susumago Hiroshi , Ando Masayoshi
Published: July 2006

The Diazotization of 2-amino-6-bromo (or alkoxy)-azulene, with alkoxycarbonyl or cyano groups at the 1 and 3-positions, by sodium nitrite in dioxane–sulfuric acid afforded mainly the corresponding 2-diazo-2,6-azulenoquinone derivatives (2a, 2b, 16). The catalytic hydrogenation of these compounds gave 1,3-disubstituted 6-hydroxyazulenes (4a, 4b, 18), from which 1,3-disubstituted 6-alkoxy- or 6-acetoxy-azulenes were obtained. The diazotization of diethyl 2-amino-6-bromoazulene-1,3-dicarboxylate (1a) in dry benzene with isoamyl nitrite in the presence of hydrogen chloride afforded the 2,6-dichloroazulene derivative (20) and the 5-bromo-2-diazo-2,6-azulenoquinone derivative (21); the latter, accompanied by a bromine addition product (22), was also obtained by the bromination of 2a. The diazotization of diethyl 2-aminoazulene-1,3-dicarboxylate (25) afforded 2a and a deamination product (26). The structure and mechanism of the formation of these diazoazulenoquinones are discussed.
The Effect of Ion Exchange on the 1,2-Epoxybutane-Isomerization Activity
Authors: Matsumoto Shigemi , Nitta Masahiro , Aomura Kazuo
Published: July 2006

The isomerization of 1,2-epoxybutane was studied over NaA-type zeolite and its zinc-exchanged forms in a flow system. The catalytic activity increased from 31 to 92% upon the replacement of Na+ by Zn2+. This increase may be the consequence of the enlargement of the zeolite pore size and the increase in the surface acidity.
Polarized Raman Spectra of (NH4)2SO4 Single Crystals
Authors: Uchida Katsuo , Takahashi Hiroaki , Higasi Keniti
Published: July 2006

Polarized Raman spectra of (NH4)2SO4 single crystals were measured at room temperature. The symmetry species of the observed Raman bands due to the internal vibrations of SO42− as well as the lattice modes were determined.
A Polarographic Study of the Complex Formation Equilibria of Lead(II) Ions with Glutamate and Ethylenediamine-N,N′-diacetate Anions
Authors: Kodama Mutsuo
Published: July 2006

In this experiment, the complex formation equilibria of the lead(II) ions with glutamic and ethylenediamine-N,N′-diacetic acids were studied by using the polarographic method. The lead(II) ion forms 1 : 1- and 1 : 2-ratio complexes with glutamic acid, while, with ethylenediamine-N,N′-diacetic acid, it forms only a 1 : 1-ratio complex, PbX0.
Kinetics of the Oxidation of Acrolein Initiated by Di-t-Butyl Diperoxyoxalate
Authors: Hara Takao , Ohkatsu Yasukazu , Osa Tetsuo
Published: July 2006

The kinetics of the liquid-phase autoxidation of acrolein were studied using di-t-butyl diperoxyoxalate as an initiator. The ratios of the rate constants for the propagation vs the termination steps (k3k6−1⁄2 and k2k4−1⁄2) in the autoxidation mechanism were determined from the empirical rate equation thus obtained. The lower reactivity of acrolein was explained by comparing the ratios with those of saturated aldehydes.
ENDOR Studies of 1,3,5-Triphenylverdazyl Radical and Its Methyl Derivatives. V.
Authors: Mukai Kazuo , Yamamoto Takamitsu , Kohno Masahiro , Azuma Nagao , Ishizu Kazuhiko
Published: July 2006

The ENDOR spectra of 1,3,5-triphenylverdazyl radical and its methyl derivatives were observed in toluene, and the effects of methyl substitution on the proton hyperfine coupling constants were investigated.
The Reaction of Dicarboximides with Benzonitrile in Liquid Ammonia
Authors: Kashima Choji , Yamamoto Makoto , Kobayashi Susumu , Sugiyama Noboru
Published: July 2006

Acyclic dicarboximides were treated with benzonitrile in the presence of sodium amide to give 4-hydroxypyrimidines. However, the reaction of succinimide with benzonitrile gave 5-hydroxy-2-phenyl-2-pyrroline-3-carboxamide. Also, glutarimide gave a similar product.
A Platinum Complex Bound to Iodinated Polystyrene by a Platinum-Carbon σ-Bond
Authors: Kawata Noboru , Mizoroki Tsutomu , Ozaki Atsumu
Published: July 2006

A platinum complex bound to iodinated polystyrene was prepared by the reaction of Pt(Pφ3)4 with iodinated polystyrene. The reaction of the synthesis was confirmed by means of direct oxidative addition of aryl iodide to Pt(Pφ3)4.
Base Catalyzed Oxygenation of 3,5-Di-t-butylpyrocatechol and Its Related Compounds
Authors: Nishinaga Akira , Itahara Toshio , Matsuura Teruo
Published: July 2006

The oxygenation of 3,5-di-t-butylcatechol (1) and its related compounds 3,5-di-t-butyl-o-benzoquinone (2), 4,6-di-t-butylpyrogallol (3), 2,4-di-t-butyl-5-oxo-2-hexenedioic acid (4), 2,4-di-t-butyl-4-(carboxyhydroxymethyl)-2-buten-4-olide (5), and 3,5-di-t-butyl-6-carboxy-2-pyrone (6) in DMF–ButOK gave 2,4-di-t-butyl-4-hydroxy-2-buten-4-olide (7b). A possible mechanism and the relation between 4, 5, and 6, the products in aqueous alkaline autoxidation of 1 and 3, are discussed.
Film Rupture of Polyvinyl Alcohol in the Presence of Surfactants
Authors: Nagashiro Waichi , Tanaka Makoto , Okabe Tadao , Oikawa Mitsuru
Published: July 2006

It was observed that polymer film coated over a mask hole broke down on drying. The phenomenon is related to the surface chemical properties of the coating solution.
The Reaction of β-Hydroxyalkylmercuric Perchlorate with Sodium Formate in an Aqueous Solution
Authors: Shinoda Sumio , Saito Yasukazu
Published: July 2006

The reaction of 2-hydroxy-1-propylmercuric perchlorate with sodium formate in an aqueous solution was found to be a redox-type reaction: CH3CH(OH)CH2HgClO4+HCOONa=CH3CH=CH2+Hg(0)+CO2+H2O+NaClO4. The concentration of the mercurial coordinated by the formate ion was determined in situ by analyzing the geminal 199Hg-1H spin-coupling constant. By changing the ratio of [CH3CH(OH)CH2HgClO4]/[HCOONa], the initial reaction rate was confirmed to be first-order with respect to the formato-mercurial: v=k[CH3CH(OH)-CH2HgOCOH]. From the variation in k with the temperature, the values of Ea=17.5 kcal mol−1 and A=4.0×108 s−1 were obtained. On the grounds of the kinetic isotope effect for DCOONa and the stereochemical study with threo- and erythro-CH3CH(OH)CHCH3HgClO4, a mechanism is proposed in which the reaction proceeds solely through the unimolecular redox-decomposition of the formato-mercurial, involving an anti-elimination of olefin coupled with a two-electron transfer from the formate ligand to the mercurial.
The Addition of Arylpalladium Chloride to 1,5-Cyclooctadiene and endo-Dicyclopentadiene
Authors: Kasahara Akira , Izumi Taeko , Endo Kazuyoshi , Takeda Toru , Ookita Motomu
Published: July 2006

1,5-Cyclooctdiene reacted with phenylpalladium chloride to give di-μ-chloro-bis-(1-phenylcyclooct-4-ene-8σ,4π)-dipalladium(II). Similarly, the reaction of endo-dicyclo-pentadiene with phenylpalladium chloride led to di-μ-chloro-bis-[endo-6-phenyl-3a,4,5,6,7,7a-hexahydro-endo-4,7-methanoindene-endo-5σ,(2–3)π]-dipalladium (II). The σ-bonded structures of these complexes have been confirmed by studies of the IR and NMR spectra.
New Benzofuranosesquiterpenes from Farfugium japonicum. Farfugin A and Farfugin B
Authors: Nagano Hajime , Moriyama Yoshihiko , Tanahashi Yoshiaki , Takahashi Takeyoshi
Published: July 2006

Two new benzofuranosesquiterpenes, farfugin A and farfugin B, have been isolated from Farfugium japonicum (L.) Kitamura, and their structures have been determined as 1 and 2, respectively.
Porous Structure Formed by the Decomposition of the Surface Product on ZnO Preserved in the Atmosphere
Authors: Nagao Mahiko , Morishige Kunimitsu , Takeshita Toshie , Morimoto Tetsuo
Published: July 2006

The slow reaction of ZnO with CO2 and water in the atmosphere is investigated by following the changes in both the surface area of the structure formed and the amounts of CO2 and water evolved, by heating the product in vacuo at increasingly elevated temperatures. The results obtained show that ZnO reacts extremely gradually with CO2 and water cooperatively in the atmosphere to produce an amorphous surface product with a composition approximate to Zn5(OH)6(CO3)2, and that this product is decomposed by heating in vacuo to release the CO2 and water, leaving a porous structure on the ZnO. The surface area of the product was found to change upon heating: first it increases, passes a prominent maximum value at 200 °C, recovers the original value at 500 °C, and further decreases at higher temperatures; this reflects the initial growth and subsequent destruction of the porous structure. Furthermore, it was confirmed that the destruction of such a honeycomb-like structure is promoted by the adsorption of water.
Magnetic Property and Electronic Structure of Tris(2,2′-bipyridine) Complexes of Manganese in Low Oxidation States
Authors: Inoue Motomichi , Hara Ken-ichi , Horiba Tatsuo , Kubo Masaji
Published: July 2006

The magnetic susceptibilities of tris(2,2′-bipyridine)manganese complexes, [Mn(bpy)3]·2THF and Li[Mn(bpy)3]·4THF (THF: tetrahydrofuran), have been determined over a temperature range of 1.6–320 K. The susceptibility of Li[Mn(bpy)3]·4THF can be explained with a radical ion model, in which three 2,2′-bipyridine radical ions are coordinated to a manganese(II) ion. A similar model is applicable to [Mn(bpy)3]·2THF as well. The presence of antiferromagnetic interaction indicates the formation of a weak covalent bond between manganese and bipyridine. This can be elucidated consistently by the molecular orbital theory.
Total Synthesis of Ferrichrome
Authors: Isowa Yoshikazu , Ohmori Muneki , Kurita Hideaki
Published: July 2006

Two different sequence hexapeptides for the synthesis of ferrichrome were prepared using Nδ-tosyl-Nδ-benzyloxy-l-ornithine by means of N-hydroxysuccinimide plus N,N-dicyclohexylcarbodiimide or Woodward reagent K method. The linear hexapeptides (XII·HCl and XIX·HCl) were cyclized by excess N,N-dicyclohexylcarbodiimide to give cyclo-triglycyltri-Nδ-tosyl-Nδ-benzyloxy-l-ornithyl (XX). Detosylation, acetylation and successive reductive debenzylation of XX afforded deferri-ferrichrome (XXIV). Addition of ferric iron to XXIV gave ferrichrome, which had the same crystalline form, superimposable infrared and well-agreeing visible spectra and the same value in optical rotation compared with the data in the literature of natural product.
A Shock-tube Investigation of Ignition in Ethylene–Oxygen–Argon Mixtures
Authors: Hidaka Yoshiaki , Kataoka Tsuyoshi , Suga Masao
Published: July 2006

The ignition of ethylene-oxygen mixtures highly diluted with argon was studied in a shock tube by monitoring the emission from CH* and C2* or OH*. The measurements covered the temperature range of 1400–2100 K at the C2H4/O2 ratios of 0.33–1.00. From the observation of the CH*, C2*, and OH* emissions, a mechanism for the production of chemiluminescent species upon ethylene oxidation was briefly discussed, and from the observation of the induction period of the CH* emission, the following equation was found:

logτ_CH[O_2]=-11.45+27.5×10^3/4.58T

in units of s mol l−1, the rate-determining step being C2H3+O2→C2H3O+O.
Linear Free Energy Relationships in Heterogeneous Catalysis. XII. Interpretation of the Catalytic Activity of Decomposition of Hydrogen Peroxide over Nickel Oxide on the Basis of Oxidation Power Distribution
Authors: Uchijima Toshio , Yoneda Yukio
Published: July 2006

Kinetic studies have been carried out on the heterogeneous decomposition of hydrogen peroxide over several nickel oxide catalysts calcined at different temperatures. Kinetic parameters such as reaction order and apparent activation energy depend somewhat on the reaction conditions, but show practically no change with catalyst. The catalytic activity changes with calcination temperature, becoming minimum at 550 °C and maximum at 600 °C. The trend does not change with pretreatment of the catalyst, resembling the behavior of surface excess oxygen having a relatively higher oxidation power. Thus the distribution of oxidation power is closely related to catalytic activity for the decomposition of hydrogen peroxide. We therefore applied the regional analysis assuming that the surface excess oxygen represents active sites for catalysis, and a specific regional activity corresponds to each regional oxygen. It was found that the fifth region (the range of free energy change of adsorption of oxygen being from −11.1 to −12.6 kcal/mol) markedly contributes to the reaction rate, and the calculated rates agree with the observed ones. The nature of the active site was discussed as regards pretreatment of the catalyst.
Kinetics of Multidentate Ligand Substitution Reactions. XVII. Substitution Reactions of Diethylenetriaminepentaacetate (DTPA) with Aminopolycarboxylate Complexes of Nickel(II) and Cobalt(II)
Authors: Kodama Mutsuo
Published: July 2006

The kinetics of the substitution reactions of DTPA with N-(2-hydroxyethyl)iminodiacetate (HIDA) and N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetate (EDTA-OH) complexes of nickel(II) and EDTA-OH and 2,2′-ethylenedioxydi(ethylamine)-N,N,N′,N′-tetraacetate (GEDTA) complexes of cobalt(II) were studied systematically by employing the polarographic technique. The reaction of ethylenediaminetetraacetate (EDTA) with the nitrilotriacetate (NTA) complex of nickel(II) in an alkaline medium was also studied. All the substitution reactions were found to have a common reaction mechanism. They were first-order with respect to DTPA or EDTA and also first-order with respect to the 1:1 ratio metal (II) complex of HIDA, NTA, EDTA-OH, or GEDTA. From a comparison of the observed rate constants with those estimated on the basis of the proposed reaction intermediate, the detailed reaction mechanism and the steric effect of the DTPA anion on the reaction rates were studied. The DTPA anion had practically no effect on the rates of the substitution reactions of the aminopolycarboxylate complexes of metal (II) ions.
The Chemistry of Protactinium. XI. A Study of the Solvent Extraction of Protactinium(IV) Reduced with Europium(II) from a Perchloric Acid Solution, Using Thenoyltrifluoroacetone as the Extractant
Authors: Kawasuji Isamu , Sato Akiko , Suzuki Shin
Published: July 2006

Europium (II) was found to be an excellent reductant for reducing protactinium in microquantities to the tetravalent state. The behavior of Pa(IV) in the perchloric acid solution was investigated by the TTA-benzene extraction method. It was found that the PaOH3+ ion existed predominantly in a 0.03–3 M perchloric acid solution at the ionic strength of 3. The reaction of TTA extraction may proceed as:

&PaOH^3++4HA=PaA_4+H_2O+3H^+

\intertextor

&PaOH^3++4HA=Pa(OH)A_3(HA)+3H^+

The distribution ratio of Pa(IV) in the system using Eu(II) as the reductant is about ten times as large as that in the system using Cr(II) as the reductant. It was considered that a non-extractable complex may be formed between Pa(IV) and Cr(III), while such a complex may not be formed when Eu(II) is used as the reductant.
The Ionic Reaction in the Chlorophosphonation of Alkylbenzenes
Authors: Okada Toshihiro , Okamoto Yoshiki , Sakurai Hiroshi
Published: July 2006

The chlorophosphonation of toluene, p-xylene, ethylbenzene, and diphenylmethane gave methyldiphenylmethanes; 2,4′,5-trimethyldiphenylmethane and ethyl-1,1-diphenylethanes; and p-benzyltriphenylmethane respectively as the main products. Isopropylbenzene gave α-methylstyrene, 4-methyl-2,4-diphenylpentene-1, 4-methyl-2,4-diphenyIpentene-2, and 1,1,3-trimethyl-3-phenylindane, in addition to the ordinary chlorophosphonated products. Those diphenylmethane derivatives may be formed by the electrophilic attack of the benzylic cations, presumably resulting from electron transfer from the benzylic radicals to phosphorus trichloride with the participation of the oxygen or oxy radical, upon toluene, p-xylene, ethylbenzene, or diphenylmethane. α-Methylstyrene may be formed by the elimination of a proton from the intermediate 1,1-dimethylbenzyl cation, resulting from isopropylbenzene in a manner similar to that above. Diphenylpentene and phenylindane derivatives may be formed by the acid-catalyzed dimerization of α-methylstyrene.
Aromatic Nucleophilic Substitution. III. Meisenheimer Complexes in the Reactions of 1-(N,N-Dialkylamino)-2,4-dinitronaphthalenes with Sodium Methoxide
Authors: Sekiguchi Shizen , Shinozaki Katsuo , Hirose Tetsuo , Matsui Kohji , Sekine Kiyoshi
Published: July 2006

The intermediates in the reaction of 1-(N,N-dimethylamino)-2,4-dinitronaphthalene (9) with sodium methoxide have been studied in the mixtures of DMSO and CH3OH. The NMR spectra of the equimolar mixture of 9 and sodium methoxide indicate that 9 and a 1,1-disubstituted Meisenheimer complex coexist immediately after mixing, and that nearly all 9 changed into the Meisenheimer complex 15 min after mixing. The addition of 2 mol of sodium methoxide to 1 mol of 9 gave no 1,1,3,3-tetrasubstituted 2,4-dinitronaphthalene Meisenheimer complex. 1-Piperidino- or 1-(N-methyl-N-n-butylamino)-2,4-dinitronaphthalene reacted with sodium methoxide to give a similar Meisenheimer complex.
Base-induced Reactions of 2-Substituted 2-Bromodimedones
Authors: Wakui Tadahiro , Otsuji Yoshio , Imoto Eiji
Published: July 2006

The reactions of 2-substituted 2-bromodimedones with various bases were studied. The behavior of the dimedones changed with the base and substituent attached to the dimedones. Treatment of 2-alkyl-2-bromodimedones (1a and 1b) with a weak nucleophilic base such as sodium acetate afforded 2-alkyl-4,4-dimethyl-2-cyclopenten-1-ones (2a and 2b), 2-alkyl-5,5-dimethyl-3-oxo-1-cyclopentene-1-carboxylic acids (3a and 3b), 2-alkyl-5,5-dimethylcyclohexane-1,3-diones (4a and 4b) and carbon monoxide. A similar treatment of 2,2-dibromodimedone (7) with the weak nucleophilic base gave 2,3-dibromo-4,4-dimethyl-2-cyclopenten-1-one (8), 2-bromo-5,5-dimethylcyclohexane-1,3,4-trione (9) and 2-bromodimedone (10). However, the reactions of 1a and 7 with a strong nucleophilic base such as sodium ethoxide gave mainly the open-chain products, ethyl 3,3-dimethyl-5-oxoheptanoate (5a) and diethyl 3,3-dimethylglutarate (11). On treatment of 1a with silver acetate, a debrominative dimerization occurred to produce the dimer 6. The mechanisms of these reactions were discussed.
A Photochemical Reaction of Lupan-3-one
Authors: Hirota Hiroshi , Tsuyuki Takahiko , Tanahashi Yoshiaki , Takahashi Takeyoshi
Published: July 2006

Lupan-3-one (5) was irradiated in n-hexane under an argon atmosphere using a high pressure mercury lamp. Besides three seco compounds, namely 10α-(2-formylethyl)-5β-isopropenyl-des-A-lupane (6), 10α-(2-carboxyethyl)-5β-isopropyl-des-A-lupane (8), and 10α-(2-carboxyethyl)-5β-isopropenyl-des-A-lupane (9), two seco-nor compounds, 10α-(carboxymethyl)-5β-isopropyl-des-A-lupane (7) and lactone of 10α-(carboxymethyl)-5α-hydroxy-5β-isopropyl-des-A-lupane (10), have been isolated and their structures have been determined. NMR signals of 10 were examined using Eu(fod)3-d27 as a shift reagent.
Dielectric Studies of ortho- and paro-Bromoanisoles and β-Bromophenetole in the Liquid State
Authors: Ghatak Alpana , Das Arati , Roy Subir Kr
Published: July 2006

Complex dielectric permittivities in ortho- and para-bromoanisoles and β-bromophenetole in the liquid state have been measured in 1.6, 3.17, and 3.49 cm microwave regions at different temperatures. The dielectric data were analysed in terms of molecular and intramolecular relaxation times. The values of methoxy group relaxation times and its contribution to total polarization obtained in the liquid bromoanisoles have been compared to the corresponding values in dilute solutions reported in literatures. Activation energy for dielectric relaxation and viscous flow in all the cases have also been obtained in all the liquids.
The Mechanism of the Reduction of Tosylhydrazones with B2H6 and with NaBH4 in Aprotic Solvents
Authors: Cacchi S , Caglioti L , Paolucci G
Published: July 2006

Cyclohexanone tosylhydrazone was reduced with NaBH4 and B2H6 in aprotic solvents; results indicate that the reduction affords cyclohexyl-tosylhydrazine or an equivalent organometallic adduct confirming the mechanism previously proposed by us in the case of NaBH4 in protic solvents.
Simple Mechanical Model Calculations of the Elastic Constants and Normal Frequencies of the NaNO2 Crystal
Authors: Yamamoto Akio , Shiro Yuji , Murata Hiromu
Published: July 2006

The optically-active vibration was analyzed for the NaNO2 crystal on the basis of a simple mechanical model. Force constants which interpret fairly well both the observed elastic constants and the vibrational frequencies of the optically-active modes were determined.