bluuebunny/crossref_metadata_2025 huggingface dataset:
Photochemical Reaction of 1,2-Naphthoquinone and Its Derivatives with Xanthene
Authors: Maruyama Kazuhiro , Takuwa Akio
Published: July 2006

In contrast to other o-quinones, photochemical reaction of 1,2-naphthoquinone with xanthene gave a 1 : 1 adduct in which xanthene moiety is attached to position C4, i.e., 1,4-dihydro-2-hydroxy-4-xanthyl-1-ketonaphthalene (2a). The analogous photo-adducts, 2b, 2c, and 2d, were obtained by the photochemical reaction of 3-chloro-1,2-naphthoquinone, 3-bromo- 1,2-naphthoquinone, and 6-bromo-1,2-naphthoquinone with xanthene, respectively. The dynamic aspect of these reactions was also examined using the CIDNP technique and the reaction mechanism was discussed.
The Viscosities of Aqueous Solutions Containing Metal Complexes. III. Iminodiacetato and Methyliminodiacetato Complexes
Authors: Mizutani Kiyoshi , Yasuda Motoo
Published: July 2006

The viscosities of aqueous solutions containing a metal chelate formed with iminodiacetic acid (H2ida) or N-methyliminodiacetic acid (H2mida) were measured with Cannon-Fenske capillary viscometers. Measurements were made in a Shibata viscosity bath maintained at 25±0.01°C. The Jones-Dole viscosity B-coefficient of each bis-ida chelate is lower than that of the corresponding bis-mida chelate, as may be expected. The B-coefficients for the mono-ida and mono-mida chelates were not determined accurately and will not be reported here. The B-value of cisN-[Co(ida)2]− is higher than that of the trans-isomer. This is probably associated with the fact that the cis-isomer interacts with the solvent more strongly than the trans-isomer.
Apparent Molal Volumes of Some Organic Electrolytes in a Dilute Aqueous Solution at 5, 25, and 45°C
Authors: Sakurai Masao
Published: July 2006

The apparent molal volumes, φv, of five series of homologous organic salts of the H(CH2)nCOONa (n=0–6), (CH2)n(COONa)2 (n=0,2,3,4,6,8), H(CH2)nNH3Cl (n=0,2,6), (CH2)n(NH3Cl)2 (n=2,3,6), and H(CH2)n-SO3Na (n=1,2) types in a dilute aqueous solution have been measured by means of a float method as a function of the concentration and the temperature. The coefficients of the deviation of φv from the Debye-Hückel limiting law, bv, are negative for most organic electrolytes. The large positive bv values observed for the sodium oxalate and sodium succinate solutions at 5°C have been attributed to ion-pair formation. The partial molal expansibility of organic ions has been evaluated and interpreted on the basis of the multilayer hydration model proposed by Frank and Wen. The estimation of volume increments per CH2 group suggests that the influences of ammonium ions on the hydrophobic hydration around CH2 groups differ significantly from those of carboxylate ions. The volume change accompanying the substitution of a terminal hydrogen atom with an ionic group has been calculated, and discussed in connection with the overlapping effect of electrostriction in bolaform electrolytes.
The Atomic Absorption Spectrophotometric Determination of Arsenic and Selenium in Premixed Inert Gas(Entrained Air)-Hydrogen Flames with a “Multi-flame” Burner
Authors: Nakahara Taketoshi , Nishino Hirohito , Munemori Makoto , Musha Sôichirô
Published: July 2006

The determination of arsenic and selenium by atomic absorption spectropho tome try was established in premixed inert gas (entrained air)-hydrogen flames using a “multi-flame” burner. Arsenic and selenium electrodeless discharge lamps were used as the sources of radiation. The optimum operating conditions for the atomic absorption measurements for arsenic and selenium at 193.7 and 196.1 nm respectively were investigated. Under the optimum conditions, the sensitivities for 1% absorption were 0.17 and 0.15 ppm for arsenic and selenium respectively. Many other elements and acids interfered with the determination of arsenic and selenium in these low-temperature flames. Most of the interferences were found to be completely eliminated, in appearance, by adding a large amount (2000 ppm) of tin(II) chloride to the sample solutions. Furthermore, a gas-sampling technique for arsenic was studied in order to improve the arsenic sensitivity and in order to eliminate the interferences from other elements. The present method was applied to the determination of arsenic in sulfide ores and steels with satisfactory results.
Peroxo-, Oxo-, and catena-Oxo-Manganese Complexes with N,N′-Ethylenebis(salicylideneimine) Analogues
Authors: Matsushita Takayuki , Yarino Tatsuo , Masuda Isao , Shono Toshiyuki , Shinra Koichiro
Published: July 2006

By the reaction of MnII(salen) (salen=N,N′-ethylenebis(salicylideneiminato) dianion) and its analogues with molecular oxygen in organic solvents, three types of complexes including as structural units the MnIII–O2–MnIII,–(–MnIV–O–)–n, and MnIV=O bonds respectively, have been obtained, and characterized by means of their electronic and infrared spectra, by thermogravimetric analysis, and in terms of their magnetic properties. The lower magnetic moments for [MnIII(salen)]2O2 and –[–MnIV(salen)–O–]–n than those expected have been interpreted in terms of antiferromagnetic interactions. The oxo complex was found to give the catena-oxo complex quantitatively in a DMF, DMSO, or Py solution. The effects of the oxygen partial pressure and the nature of the substituent in the organic part on the complex formation were investigated. A lower partial pressure of oxygen has the advantage of yielding the μ-peroxo complex in a higher yield. A discussion of the reaction mechanism is also included.
The Hydrolysis of Y3+, La3+, Gd3+, and Er3+ Ions in an Aqueous Solution Containing 3 M (Li)ClO4 as an Ionic Medium
Authors: Amaya Toshihiko , Kakihana Hidetake , Maeda Masunobu
Published: July 2006

The hydrolysis equilibria of Y3+, La3+, Gd3+, and Er3+ ions have been studied at 25°C in 3 M (Li)ClO4 by measuring the hydrogen-ion concentration with a glass electrode. All the test solutions containing hydrolyzed species prepared by the addition of alkali were acidified by means of constant-current coulometry. The data, which indicate a slight hydrolysis of the relevant ions, can be explained by assuming the formation of the following complexes: Y(OH)2+, logβ2,1=−17.0±0.1; Y2(OH)24+, logβ2,2=−14.04±0.01; LaOH2+, logβ1,1=−10.04±0.01; GdOH2+, logβ1,1=−8.20±0.01; Er(OH)2+, logβ2,1=−17.4±0.1; Er2(OH)24+, logβ2,2=−13.72±0.01.
Studies on Nitrogen-Phosphorus Compounds. XXII. The Synthesis and Properties of Phosphoric Aniline Diamide
Authors: Kobayashi Etsuro
Published: July 2006

In order to develop fireproof materials, a new compound, phosphoric aniline diamide, was prepared by employing phosphorus oxychloride, aniline, and ammonia as the starting materials. The conditions for the synthesis and the characteristics of the product have been investigated. Phosphoric aniline diamide can be prepared in the following way: 2 moles of aniline are added to 1 mole of phosphorus oxychloride diluted with chloroform, and the precipitate of aniline hydrochloride, a by-product, is separated from the solvent by filtration. A mixture of phosphoric amide and ammonium chloride is formed by the reaction between an excess of gaseous ammonia and the above filtrate at −10–20°C, and is then separated from the mother liquor. Crude phosphoric amide is extracted from the mixture with ethanol, and subsequent re-extraction with acetone yields the pure product with the formula PONHC6H5(NH2)2. The product thus obtained is composed of a white crystalline powder, soluble in water, ethanol and acetone but insoluble in various organic solvents. The compound shows its own characteristic X-ray diffraction pattern and IR absorption bands. Upon heating, the product melts at about 140°C; condensation occurs by de-ammoniation above 170°C, and conversion into insoluble condensed amidophosphates takes place.
The Estimation of the Electronic Effects of Cyclopropyl and 2,2-Dichlorocyclopropyl Groups
Authors: Kusuyama Yoshiaki , Ikeda Yoshitsugu
Published: July 2006

The normal substituent constant, σ0, and the resonance substituent constant, Δ\barσR+, in the Yukawa and Tsuno treatment of cyclopropyl and 2,2-dichlorocyclopropyl were determined by the ionization of m-, p-substituted phenylacetic acids in 50% aqueous ethanol and by the solvolysis of α-(m-, p-substituted phenyl) ethyl chlorides in 80% aqueous acetone. For cyclopropyl, the obtained σ0 value indicates an inductive electron-attracting behavior, while the Δ\barσR+ value indicates a marked enhancement of the electron-releasing resonance effect on the electron deficient reaction center compared with alkyl groups. A minor resonance contribution was observed for the 2,2-dichlorocyclopropyl group.
Magnetic Susceptibilities of Solid Oxygen-Argon Mixtures
Authors: Mori Yoshihiro , Sakakibara Akira , Inokuchi Hiroo
Published: July 2006

The magnetic susceptibility in solid oxygen-argon mixtures has been obtained as a function of the temperature from 12 K to the melting point. In case of the 95% O2–5% Ar system, the behavior of the magnetic susceptibility was similar to that of pure oxygen except for some dynamical effects caused by the addition of argon to the oxygen lattices. In the composition range between 92% and 66% O2, the appearance of a novel phase, δ, was observed from the magnetic susceptibility measurements; its temperature and concentration dependence was discussed qualitatively on the basis of the crystal structure.
Synthesis and Biological Activity of Peptides Related to Eledoisin. II. Hexapeptide Amides Containing N-Methylamino Acids
Authors: Sugano Hiroshi , Higaki Ko , Miyoshi Muneji
Published: July 2006

Eledoisin-like hexapeptides were synthesized in order to obtain longer-lasting hypotensive analogs. A part of the amino acid of the standard pep tide, H–Lys–Phe–Ile–Gly–Leu–Met–NH2 (1), was replaced by N-methylamino acid. It was found, in these syntheses, that when the C-terminal amino acid of a carboxy component was an N-methylamino acid, a system of dicyclohexylcarbodiimide plus 1-hydroxybenzotriazole was a useful coupling agent. With regard to the hypotensive effect in rabbits, H–Lys–Phe–Melle–Gly–Leu–Met–NH2 (2) and H–Lys–Phe–Ile–Gly–Melle–Met–NH2 (6) show much less activity; H–Lys–MePhe–Ile–Gly–Leu–Met–NH2 (3) and H–Lys–MePhe–Ile–Gly–MeLeu–Met–NH2 (7) show a substantial activity, though weaker than the standard one. On the other hand, H–Lys–Phe–Ile–Gly–MeLeu–Met–NH2 (5) and H–Lys–Phe–Ile–Sar–Leu–Met–NH2(4) show a higher activity than 1. These results indicate that, in some cases, the replacement of an amide bond by an N-methylamide bond without any change in the side chain of amino acid would have an important influence on the activity. The duration of the action of N-methypeptildes synthesized was unexpectedly of the same order of magnitude as that of 1.
Binuclear Metal Complexes. VII. Preparation and Properties of Binuclear Copper(II) and Nickel(II) Complexes of Hydrogen-bridged Macrocycles
Authors: Okawa Hisashi , Tokii Tadashi , Muto Yoneichiro , Kida Sigeo
Published: July 2006

Two types of binuclear copper(II) and nickel(II) complexes, OK-3(H), 3(H)-M2 and [OK-m, 3(H)-M2]ClO4 (m=2 or 3), have been synthesized, where OK-3(H),3(H) is a macrocycle composed of two 2,6-diformyl-4-methylphenol and four hydroxylamine, and OK-m,3(H) is a macrocycle composed of two 2,6-diformyl-4-methylphenol, one diamine (ethylene diamine (m=2) or 1,3-diaminopropane (m=3)), and two hydroxylamine. It was found that a very strong antiferromagnetic exchange interaction is operating between two copper(II) ions for OK-3(H), 3(H)-Cu2 and [OK-2,3(H)-Cu2]ClO4. The complex [OK-2,3(H)-Ni2]ClO4. DMF was found to be a novel-type binuclear nickel(II) complex, in which one nickel (II) ion is diamagnetic and the other is paramagnetic.
Syntheses of Isomaltose, Isomaltotetraose, and Isomaltooctaose
Authors: Koto Shinkiti , Uchida Tetsuo , Zen Shonosuke
Published: July 2006

Ethyl 2,3,4-tri-O-benzyl-6-O-p-nitrobenzoyl-1-thio-α-d-glucopyranoside (I–1) was brominated and subsequently condensed with a deacylated derivative of I–1 in nitromethane in the presence of 2,6-lutidine to give ethyl 2,2′,3,3′,4,4′-hexa-O-benzyl-6′-O-p-nitrobenzoyl-1-thio-α-isomaltoside (I–2) in a 92% yield. These processes were repeated on I–2 to give the blocked tetrasaccharide (I–4) in a 49% yield. Finally, the octasaccharide (I–8) was synthesized in an 11% yield by one more repetition of this reaction cycle. The blocked glycosides, I–2, I–4, and I–8, gave isomaltose, isomaltotetraose, and isomaltooctaose respectively after the sequence of unblocking processes: bromolysis, hydrolysis, methanolysis, and hydrogenolysis.
Hetera-p-carbophanes. I. Hetera-p-carbophanes Containing Two Amide Groups
Authors: Sakamoto Kazuhiko , \={O}ki Michinori
Published: July 2006

Several hetera-p-carbophanes containing two amide groups in the ansa chain were synthesized by the highdilution method. Those which have shorter ansa chains than 15 atoms show no sign of the internal rotation of the benzene ring, even at higher temperatures, whereas that which has the ansa chain of 16 atoms shows no sign of the freezing of the motion, even at lower temperatures. The infrared spectra of these compounds suggest that the amide groups in these compounds exist as the s-cis conformation.
ESR Studies of the Cation Radicals Produced by SbCl5 Oxidation of Some Biphenyls with ortho- and para-Dialkyl Substituents
Authors: Ishizu Kazuhiko , Ohuchi Muneki , Nemoto Fujito , Suga Masao
Published: July 2006

The cation radicals of some alkylbiphenyls such as 4,4′-bitolyl, 4,4′-di-t-butylbiphenyl, and 2,2′, 4,4′, 6,6′-bimesityl, were generated by SbCl5 oxidation in CH2Cl2. The ESR observation was carried out, and the Q, values of the methyl and t-butyl were estimated based on either the theoretical spin density or the experimentally-determined spin density from the 13C-hyperfine splitting. The Q, value of the methyl in the cation radical was found to be 1.5 times that for the anion radical. The t-butyl groups of the cation radical also showed a much larger Q value than that for the anion radical. The perturbation of the spin density due to the steric hindrance was investigated with reference to the prediction of the McLachlan’s MO calculations carried out for the hindered biphenyl. The experimentally-determined spin density derived from the Q value established for the para-derivative can be adequately interpreted on the assumption that the planar character of the biphenyl would be much reduced, contrary to the tendency found for the anion radicals. This effect suggests that a different delocalization of the unpaired electron may be expected between the cation and the anion radical: that is, the unpaired electron brings about a fair bonding on the central 1–1′ bond in the anion radical, but an antibonding for the cation radical, because the odd π-orbital of the cation has its node between the central 1–1′ bond.
The Electronic States of p-Bromanil and Its Anion Radical as Studied by Means of Their Infrared Spectra
Authors: Iida Yôichi
Published: July 2006

The infrared spectra (400–4000 cm−1) were measured with neutral p-bromanil and its anion radical. Appreciable frequency differences between their corresponding bands were observed. The fundamental frequencies were assigned, and the simple Urey-Bradley force fields were determined for both the neutral p-bromanil and its anion radical. The differences in the molecular and electronic structures between these two molecules were discussed on the basis of these results. The half-occupied molecular orbital of the p-bromanil anion radical was found to belong to the b3g irreducible representation.
The Crystal Structure of Trimellitic Acid for the Pseudo-cell
Authors: Takusagawa Fusao , Hirotsu Ken , Shimada Akira
Published: July 2006

The crystal structure of trimellitic acid(benzene-1,2,4-tricarboxylic acid) for the pseudo-cell was determined by the method of X-ray diffraction. The crystal is monoclinic, with the space group of I2/c and with a=15.91, b=61.35, c=8.99 Å, and β=95.4°. The appearence of diffraction patterns strongly indicated the existence of the pseudo-cell with b⁄5 and with the space group of I2/c. The structure of the pseudo-cell was determined by the symbolic addition method. The final R value is 13.6%. There is no intramolecular hydrogen bond between the adjacent carboxyl groups, and one of these carboxyl groups twists greatly out of the plane of a benzene ring so that the repulsion between the oxygen atoms is reduced. Each molecule is joined, through three kinds of hydrogen bonds, with three neighboring molecules. These hydrogen bonds are formed between the carboxyl groups related by the center of symmetry and the two-fold axis. The molecular dimensions and packing obtained by the refinement for the pseudo-cell do not seem to contain unacceptable results.
The Effect of the Temperature on the Mass Spectra of Aliphatic Primary Alcohols and 1-Alkenes. I.
Authors: Hoshino Hiroko , Tajima Susumu , Tsuchiya Toshikazu
Published: July 2006

The decomposition of the (M–18)\underset.+ ion of aliphatic alcohols and that of the M\underset.+ ion of 1-alkenes are studied. The temperature effect of the ion source of a mass spectrometer on the ratios of the intensities of these ions, those of the ions produced from them by C2H4 elimination, and those of the metastable ions for the corresponding fragmentation was measured and was compared with the results to be expected from a simple QET consideration. A discrepancy between the result expected and the experimental result was found for 1-alkenes. In order to clarify the cause of the discrepancy, the photoelectron spectrum was measured for 1-hexanol and for 1-hexene and was assumed to represent the internal energy distribution function, P(E), for each of these substances. Taking the shape of the P(E) into account, the result for 1-alkenes was explained.
Molecular Association and Electronic Spectra of Naphthoic Acids: Formation of an Excimer-like Complex in 1-Naphthoic Acid in Rigid-Glass Matrix
Authors: Kitamura Michio , Baba Hiroaki
Published: July 2006

Absorption and fluorescence spectra of 1- and 2-naphthoic acid (1- and 2-NA) have been studied in a hydrocarbon rigid-glass matrix at 77 K and in the crystal. Each of these acids is associated to form a hydrogen-bonded dimer. On increasing the concentration of 1- or 2-NA, the dimer is further associated to give a higher-order complex that may be assumed to be a tetramer. The fluorescence spectra of the monomer and dimer are in mirror-image relation to their respective absorption spectra in both 1- and 2-NA. When the tetramer of 1-NA is photo-excited, a broad structureless fluorescence emission appears, with the maximum at ca. 7000 cm−1 to the red from the 0–0 band of the dimer fluorescence. The structureless fluorescence spectrum, which has no mirror-image relation to the absorption spectrum of the tetramer, is supposed to originate from an “excimer-like tetramer” of 1-NA. Photo-excitation of the 2-NA tetramer results in a structured fluorescence emission which is considered to come from the simple excited state of the tetramer. The fluorescence lifetimes, quantum yields, and fluorescence-polarization spectra were measured for various molecular species of 1- and 2-NA. The natural fluorescence lifetime of the excimer-like tetramer of 1-NA is evaluated to be 320 nsec, which is 51 times as long as that of the dimer, and the fluorescence from the excimer-like tetramer is polarized mainly along the short molecular axis of the naphthalene nucleus. It is concluded from these observations that the excimer-like tetramer has a symmetrical configuration, with the planes of the constituent dimer molecules parallel to each other, and its fluorescence process is essentially symmetry forbidden.
Circular Dichroism and Absolute Configuration of Triammine(sarcosinate-N-monopropionato)cobalt(III) Chloride and Several Analogues
Authors: Okamoto Ken-ichi , Hidaka Jinsai , Shimura Yoichi
Published: July 2006

cis(O)- and trans(O)-Trianimine(sarcosinate-N-nionopropionato)cobalt(III) salts, which have an asymmetrically coordinated nitrogen atom, were prepared and the cis(O) isomer was optically resolved through its diastereomeric salt with (+)546-(ethylenediaminetetraacetato)cobaltate(III) anion. The less soluble diastereomeric salt produced (+)546-cis(O) isomer of the triammine cation, and its absolute configuration (R) was established from circular dichroism spectrum, referring to the stereochemistry of the several analogous triammine complexes stereo-specifically formed, which contain l-alaninate- and l-prolinate-N-monocarboxylate ligands, where the carboxylate stands for acetate or propionate. Two diastereomeric isomers, R(N)–l(C) and S(N)–l(C), were synthesized for the cis(O)-(l-alaninate-N-monopropionato)triamminecobalt(III) perchlorate salt.
The Synthesis and the Absolute Configurations of Lilac Alcohols, New Naturally Occurring Odorous Ingredients of Lilac Flower
Authors: Wakayama Seiji , Namba Satoshi , Hosoi Kazuo , Ohno Masaji
Published: July 2006

The conversion of racemic linalyl acetate to racemic lilac alcohols has been completed in 5 steps and four diastereoisomers of β,5-dimethyl-5-vinyl-2-tetrahydrofuranethanol were obtained. d-Lilac alcohols were also synthesized from d-linalyl acetate and confirmed to be identical with natural ones. The absolute configurations of lilac alcohol-a, -b, -c, and -d were respectively shown to be (βS, 2S, 5S), (βR, 2S, 5S), (βR, 2R, 5S), and (βS, 2R, 5S) by the chemical and physical evidences.
Branched-chain Sugars. III. Addition of Vinylmagnesium Bromide to 5,6-Dideoxy-1,2-O-isopropylidene-6-C-nitro-3-O-substituted-α-d-xylo-hex-5-enof uranoses
Authors: Iida Takao , Funabashi Masuo , Yoshimura Juji
Published: July 2006

Addition of vinylmagnesium bromide to 3-O-acetyl (1) and 3-O-benzyl (3) derivatives of 5,6-dideoxy-1,2-O-isopropylidene-6-C-nitro-α-d-xylo-hex-5-enofuranose gave the corresponding 5-deoxy-5-C-vinyl derivatives of l-ido-type, of which the configurations were proved by intramolecular cyclization into the corresponding nitrocyclitojs. Conformations of 1 and 3 and that of the transition state in the addition reaction were discussed on the basis of their NMR parameters.
Studies on Aminosugars. XXXVI. Syntheses of 3′,4′-Dideoxy-and 3′,4′,5″-Trideoxyribostamycin
Authors: Ikeda Daishiro , Suzuki Toshihisa , Tsuchiya Tsutomu , Umezawa Sumio , Umezawa Hamao
Published: July 2006

3′,4′-Dideoxyribostamycin and 3′,4′,5″-trideoxyribostamycin have been prepared from ribostamycin via 3′,4′-unsaturation and 5″-iodo-3′,4′-unsaturation intermediates, respectively.
The Reaction of Arylthallium(III) Compounds with Copper(II) and (I) Thiocyanates
Authors: Uemura Sakae , Uchida Satoru , Okano Masaya , Ichikawa Katsuhiko
Published: July 2006

Arylthallium(III) acetate perchlorates reacted with copper(II) thiocyanate to afford aryl thiocyanates in various solvents. The Cu(I) salt was found to be less effective for the thiocyanation. The choice of solvent and the addition of potassium thiocyanate had a significant effect on the yield of aryl thiocyanates. The reaction with the mixture of copper(II) and potassium thiocyanates (1: 1) in dioxane showed the best result. Electron-releasing groups in the aromatic ring accelerated hydrodethallation, yielding aromatic hydrocarbons with a depression of the thiocyanate formation.
Improved Solid-Phase Synthesis of Tryptophan-Containing Peptides. II. Use of Nα-t-Butyloxycarbonyl-Ni-formyltryptophan
Authors: Ohno Motonori , Tsukamoto Sadaji , Sato Shin-ichi , Izumiya Nobuo
Published: July 2006

Ni-Formyltryptophan has proved to be more resistant than tryptophan against oxidation mediated by hydrogen chloride in acetic acid. Nα-t-Butyloxycarbonyl-Ni-formyltryptophan has been synthesized via nonaqueous acylation reaction and used for the solid-phase synthesis of tryptophan-containing peptides, in combination with hydrogen chloride in formic acid as the reagent for cleavage of the t-butyloxycarbonyl group. The validity of the method has been demonstrated, on the basis of several criteria, in the synthesis of the tryptophan-containing octapeptide, Lys–Gly–Val–Leu–Ala–Gly–Trp–Leu.
Molar Volume of Ions
Authors: Hirata Fumio , Arakawa Kiyoshi
Published: July 2006

A formula based on the scaled particle theory of fluids has been derived for the intrinsic volume of ions. Validity ranges of earlier semiempirical formulas are discussed in the light of the formula. Using the theoretical values of the intrinsic volumes of ions, values of volume contraction caused by ion-water interactions are estimated.
X-Ray Photoelectron Spectroscopic Study for the Reaction of Evaporated Iron with O2 and H2O
Authors: Kishi Kosaku , Ikeda Shigero
Published: July 2006

Reactions of evaporated iron with O2 and H2O have been investigated by X-ray photoelectron spectroscopy. Binding energies of Fe2p3⁄2 and Ols electrons were measured during the course of reactions and their variation was discussed in terms of the positive and negative charges of the iron and oxygen of the surface oxide formed, respectively, assuming a simple charge-chemical shift relation. They are compared with the binding energies of the Ols in SiO2 Al2O3, Fe2O3, Cd(OH)2, KOH, and Ni(OH)2 and those of Fe2p3⁄2 in various iron compounds High reactivity of the surface oxide with H2O and the resulting hydroxyl group formation were observed. A rough estimation of the Fe to O atomic ratio of the surface oxide was also carried out from the ratio of the Fe and O peak areas.
The Dissolution of CaMg(SiO3)2 in Acid Solutions
Authors: Sanemasa Isao , Katsura Takashi
Published: July 2006

The dissolution phenomena of synthesized diopside, CaMg(SiO3)2, and a glassy material of the same composition in an acid solution were studied. The results observed in the dissolution of the glass were as follows; the molar concentrations of Ca dissolved in the solution are equal to those of Mg throughout the dissolution of the glass. The rate at which the cations go into solutions are proportional to the surface area up to about a 60% dissolution. The dissolution behavior of silica is similar to that of cations. A residual layer rich in silica is formed, one which is no longer dissolved after the removal of the cations. The results observed in the dissolution of the crystalline diopside were as follows; there is an initial rapid dissolution of the components, followed by another process. The molar ratios of the Ca ions to the Mg ions, and of each cation to silica in the solutions, are larger than those in the solid during the course of the reaction; they are especially large in the initial dissolution stage. An essential feature of diopside dissolution is that the Ca ions are more readily removed from the crystal than are the Mg ions. This fact is also confirmed in the natural diopside crystal. While the rates of the dissolution of the cations are not affected by the concentrations of HCl and HClO4, the concentration of H2SO4 does have an influence. Diopside cannot be dealt with as a single species participating in the heterogeneous reaction because its various components show selective dissolution. The mechanism of the dissolution of diopside will be discussed in connection with its structure.
The Nucleophilic Ring-opening Reactions of α,α′-Dinitrocycloalkanones
Authors: Kobayashi Yoshinari
Published: July 2006

The keto and enolic characters of 2,6-dinitrocyclohexanone (1), 2,6-dinitro-4-methylcyclohexanone (2), and 2,7-dinitrocycloheptanone (3) were spectroscopically investigated and discussed. It was found that the reactions of 1 and 2 with nucleophiles can take either of two courses, depending upon the nucleophiles used: (a) the addition to the enol carbon or carbonyl carbon of the keto form, followed by ring-opening giving 2,6-dinitro- and 2,6-dinitro-4-methyl-hexanoates respectively; (b) the abstraction of the 2- and 6-protons, followed by the formation of the corresponding di-aci-nitronates. Primary alkoxide ions belong to the (a) group, whereas secondary and tertiary alkoxide ions, NH−2, RHN−, and AcO−, belong to the (b) group. The IR and UV spectra of the resultant α,ω-dinitrocarboxylic acid esters were also discussed.
Effect of Pressure on the Rate of Solvolysis. Hydrolysis of 1-Aryl-1-methylethyl Chlorides
Authors: Sera Akira , Miyazawa Toshifumi , Matsuda Tadashi , Togawa Yoichi , Maruyama Kazuhiro
Published: July 2006

The effect of pressure on the hydrolysis rates of 1-aryl-1-methylethyl chlorides were investigated, and the activation volumes, ΔV0\eweq, were calculated. Electron-donating substituents in an aryl group gave less negative ΔV0\eweq values and electron-withdrawing substituents gave more negative ΔV0\eweq values. The observed values of ΔV0\eweq were found to correlate with σ+. These observations are interpreted in terms of the dependence of the degree of solvation at the transition state of the reaction. The temperature dependence of ΔV0\eweq is also discussed.
The Biosynthesis of Geraniol and Citronellol in Pelargonium roseum Bourbon
Authors: Suga Takayuki , Shishibori Tsuyoshi
Published: July 2006

Geraniol and citronellol were biosynthesized from [2-14C]mevalonic acid by the leaves of Pelargonium roseum Bourbon, The degradation of the radioactive specimens revealed that the major radioactivity (70–80%) was located at C-4 in the skeleton derived presumably from isopentenyl pyrophosphate and the rest of the activity at C-8 (and/or C-10) in the moiety from 3,3-dimethylallyl pyrophosphate. The unbalance of labeling was distinct from the result observed for the monoterpenes biosynthesized from the same labeled precursor by the flowers of the rose. A discussion is given on factors causing such a discrepancy in the labeling pattern owing to the difference of the plant and/or the organ. Time-course experiments with the use of [2-14C]mevalonic acid indicated the formation of geraniol prior to citronellol both in the intact plant and in the cell-free extract.
Kinetics of Oxygen Exchange between Arsenate Ions and Water. II. Catalysis by Arsenious Acid
Authors: Okumura Akiko , Yamamoto Noriko , Okazaki Nobukazu
Published: July 2006

Oxygen exchange between arsenate ions and water is catalyzed by arsenious acid. The catalytic effect has been studied at 14.5 °C and 30.0 °C over the pH region of 7.5–10.2. The increase in the exchange rate due to the addition of arsenious acid, Rc may be expressed as: Rc≈k[H+][As(III)][As(V)]. The results are interpreted in terms of the rapid reversible condensation of the As(III) with the As(V) species to form the arsenitoarsenate ions.
Circular Dichroism and Optical Rotatory Dispersion Spectra of Poly[γ-(1-naphthylmethyl)-l-gIutamate] and Its Charge-transfer Complex
Authors: Hatano Masahiro , Enomoto Takamichi , Ito Ichi , Yoneyama Michio
Published: July 2006

Poly-γ-(1-naphthylmethyl)-l-glutamate was synthesized and its structure analyzed by the measurements of circular dichroism and absorption spectra. When the circular dichroism band at 219 nm in the circular dichroism spectrum of the polymer can be assigned to the band due to n–π* transition in the peptide main chain of the polymer, the calculated content of the right hand helix in the polymer is about 54% in ethylene chlorohydrin solution. It was also found that the polypeptide can form a charge-transfer complex with an organic electron acceptor in ethylene chlorohydrin solution. In the charge-transfer complex, a circular dichroism band could be observed at the wavelength corresponding to that of the charge-transfer band in the absorption spectrum of the complex. From the results, it was confirmed that the charge-transfer complex contains α-helix structure of this polypeptide. The temperature dependence of the charge-transfer complex formation was discussed in terms of the formation constant and thermodynamic parameters. The polypeptides having various portions of the 1-naphthylmethyl-d-glutamate residue were synthesized from poly-γ-methyl-d-glutamate by a polymer reaction using p-toluenesulfonic acid. The values of b0 for the polypeptides derived from poly-γ-methyl-d-glutamate were estimated by means of Moffitt-Yang’s equation, and the correlation between the b0 values and the contents of 1-naphthylmethyl residue in the polypeptides was discussed.
Determination of Electrochemical Kinetic Parameters of Porphyrins and Metalloporphyrins in N,N′-Dimethylformamide by Radio Frequency Polarographic Method
Authors: Kakutani Tadaaki , Senda Mitsugi
Published: July 2006

Electrochemical kinetic parameters were determined for the first two reduction steps of some porphyrins and divalent metalloporphyrins in DMF containing 0.5 M TEAP at 25 °C by use of radio frequency polarographic method. The results were discussed in view of their molecular structures and the diffuse double layer effect on the kinetic parameters.
A Study on Spontaneous Resolution of Cobalt(III) Complex Salts
Authors: Yamanari Kazuaki , Hidaka Jinsai , Shimura Yoichi
Published: July 2006

Solubility of the racemic and optically active isomers of [Co(ox)en2]X, [CoCO3en2]X, cis-[Co(NO2)2en2]X and M[Co(edta)] in water was determined at 5–60 °C (X=Cl, Br, and I; M=NH4 and K). The correlation between solubility of the spontaneously resolved racemic complex and of the corresponding optically active isomer is discussed. Spontaneous resolutions were observed for [Co(ox)en2]X (X=Cl, Cl·H2O, and Br·H2O), cis-[Co(NO2)2-en2]X (X=Cl and Br) and M[Co(edta)]·2H2O (M=NH4 and K).
The Chemical Behavior of Low Valence Sulfur Compounds. VIII. The Oxidation of Sodium Thiosulfate with Ozone
Authors: Takizawa Masahiro , Okuwaki Akitsugu , Okabe Taijiro
Published: July 2006

The oxidation of sodium thiosulfate with ozone in an aqueous solution was investigated as a part of a series of studies on the chemical behavior of such low-valence sulfur compounds as thiosulfate and sulfite. The ozone oxidation was carried out by blowing a mixed gas of ozone and oxygen continuously into a 0.3–0.6 mol/l solution of sodium thiosulfate at 10–80°C. In a neutral solution, thiosulfate is converted to sulfate, sulfite, tri- and tetrathionates, hydrogen sulfide and sulfur dioxide, and finally to sulfate, tri- and tetrathionates. The yield of the sulfate is only 40% of the total sulfur. In an alkaline solution, however, thiosulfate is oxidized to sulfite as an intermediate, and finally to sulfate.

The oxidation of sodium sulfite, and potassium salts of tri- and tetrathionate with ozone was also studied in order to elucidate its mechanism.
Studies on Reactions of the N-Phosphonium Salts of Pyridines. III. A New Method for the Activation of Amines via the N-Phosphonium Salts by Means of Oxidation of Phosphorous Acid and Its Esters in the Presence of Tertiary Amines
Authors: Yamazaki Noboru , Higashi Fukuji
Published: July 2006

Amines were treated with the N-phosphonium salts of pyridine prepared by the oxidation of the phosphorous acid and its esters with mercuric chloride in pyridine; they yielded the corresponding amides in good yields upon acidolysis with carboxylic acids, together with metallic mercury in a nearly quantitative yield. The reaction was studied using phosphorous acid and its several esters, and was presumed to proceed via the activation of amines by the N-phosphonium salts of pyridine which were characterized by IR spectroscopy. This process for the activation of amino groups was successfully extended to peptide synthesis in pyridine at low temperature using diphenyl phosphite.
Mechanism of Transylidation of Stable Sulfonium Ylids with Alkyl Sulfides in the Presence of Catalytic Disulfides
Authors: Matsuyama Haruo , Minato Hiroshi , Kobayashi Michio
Published: July 2006

In the presence of bis(trifluoromethyl) disulfide, methylphenylsulfonium bis(methoxycarbonyl)methylid is readily attacked by a nucleophile (an alkyl sulfide or a pyridine) and the corresponding new ylid is produced. In the NMR spectrum of a mixture of an ylid, an alkyl sulfide, and a catalytic disulfide, a remarkable broadening in the signals of the α-hydrogen of the sulfide was observed. A mechanism is suggested, which involves a complex from the two reactants and the catalyst.
α,β-Unsaturated Carboxylic Acid Derivatives. IV. General Synthesis of Unsaturated Unsymmetric 3,6-Disubstituted-2,5-piperazinediones
Authors: Shin Chung-gi , Sato Ken-ichi , Ohtsuka Akira , Mikami Kazutoshi , Yoshimura Juji
Published: July 2006

A general synthetic route to unsymmetric 3,6-dialkylidene and 3-alkylidene-6-arylidene-2,5-piperazinediones is described. The condensation reaction of ethyl 2-oxocarboxylates with chloroacetamide in the presence of several acidic catalysts afforded N-chloroacetyldehydroamino acid esters. These compounds were cyclized in saturated ethanolic ammonia to give 3-monoalkylidene and benzylidene-2,5-piperazinediones (2). Compound 2 and 1-monoacetyl- or 1,4-diacetyl-3-alkylidene and benzylidene-2,5-piperazinediones, derived from a reaction of 2 with acetic anhydride, were condensed with alkyl and arylaldehyde in the presence of bases to afford 5.
The Molecular Structure of Antimony Trichloride as Determined by Gas-electron Diffraction
Authors: Konaka Shigehiro , Kimura Masao
Published: July 2006

The molecular structure and mean amplitudes of SbCl3 have been determined, by the sector-microphotometer method of gas-phase electron diffraction, to be as follows: rg(Sb–Cl)=2.333±0.003 Å, rg(Cl–Cl)=3.50±0.02 Å, θα=97.2°±0.9°, l(Sb–C1)=0.063±0.004 Å, and l(Cl–Cl)=0.147±0.014 Å. The zero-point average structure derived from the diffraction results by the use of the estimated potential constants is consistent with the rotational constants, Bz, derived from the Bo of microwave measurements. The joint use of the ED and MW data has given a value of 2.326±0.001 Å for rz(Sb–Cl).
Electron Diffraction Study of Dimethylmercury
Authors: Kashiwabara Kuniaki , Konaka Shigehiro , Iijima Takao , Kimura Masao
Published: July 2006

Electron scattering by dimethylmercury has been studied for 42 keV electrons. The theoretical scattering factors currently used have shown satisfactory conformity to the observed scattering intensity, with the following distance parameters: rg(Hg–C)=2.083±0.005 Å, rg(Hg…H)=2.71±0.02 Å, and rg(C–H)=1.106 Å (assumed). A comparison of the background functions has revealed that the scattering factors based on the relativistic Hartree-Fock-Slater potential are better than those based on the Thomas-Fermi-Dirac and Thomas-Fermi potentials. The zero-point average distance determined from the spectroscopic data has shown significant inconsistency with the diffraction result. The diffraction value is shorter than the spectroscopic one by 0.015 Å.
Electron Diffraction Investigation of Gaseous Mercury(II) Chloride
Authors: Kashiwabara Kuniaki , Konaka Shigehiro , Kimura Masao
Published: July 2006

The molecular structure of mercury (II) chloride has been determined by the sector-microphotometer method of gas-phase electron diffraction at accelerating voltages of 29 and 42 kV. The parameter values obtained are: rg(Hg–Cl), 2.252±0.005 Å; l(Hg–Cl), 0.052±0.005 Å; rg(Cl–Cl), 4.48±0.04 Å; and l(Cl–Cl), 0.09±0.04 Å. A linear structure has been confirmed within an error of 16°. The experimental mean amplitudes are consistent with the estimated values based on the spectroscopic data. No appreciable differences in the structure parameters have been found between the results of analysis carried out on the basis of the Thomas-Fermi-Dirac and the relativistic Hartree-Fock-Slater scattering factors.
The Molecular Structure and Force Constants of Antimony Tribromide as Determined by Gas-phase Electron Diffraction
Authors: Konaka Shigehiro , Kimura Masao
Published: July 2006

The molecular structure and mean amplitudes of SbBr3 at 102°C have been determined by the sector-microphotometer method of gas-phase electron diffraction to be as follows: rg(Sb-Br)=2.490±0.003 Å, rg(Br-Br)=3.76±0.01 Å, θα=98.2°±0.6°, l(Sb–Br)=0.060±0.003 Å and l(Br–Br)=0.15±0.01 Å. General quadratic force constants have been determined from the observed mean amplitudes and vibrational frequencies. The molecular structure supports the validity of the empirical rules between a bond length and the covalent radii and electronegativities of its constituent atoms. An empirical equation, θ(YXY)=92+8xX−3xY(+xZ), has been proposed for the bond angles of Vb-group halides, (Z)XY3, and the electronegativities, x.
Polarographic Reductions of Alkaline Earth Metal Ions in Hexamethylphosphoramide. Effect of Cation of the Supporting Electrolyte
Authors: Izutsu Kosuke , Sakura Sachiko , Fujinaga Taitiro
Published: July 2006

Polarographic reductions of barium, strontium and calcium ions in hexamethylphosphoramide (HMPA) have been investigated in the supporting electrolytes of various perchlorates. The reduction of these alkaline earth metal ions are strongly influenced by the cation of the supporting electrolyte. When the size of the cation of the supporting electrolyte is small and easily adsorbed on the negatively charged electrode surface as in the cases of Me4N+ and Et4N+ ions, the reduction of the metal ions does not occur until that of the supporting electrolyte. The reduction becomes easier with the increase of cationic size. Thus, in Hex4NClO4 or LiClO4, these metal ions are reduced almost reversibly. These effects of the cation of the supporting electrolyte can be explained as electrode surface phenomena as in the reduction of alkali metal ions.
Study on Oxazolopyrimidines. VI. Formation of 3-Substituted Xanthines via 7(6H)-Iminooxazolopyrimidines
Authors: Ohtsuka Yozo
Published: July 2006

The condensation of several primary amines with 4-cyano-5-dialkoxymethylenaminooxazole gave 6-substituted 5-alkoxy-7(6H)-immooxazolo[5,4-d]pyrimidines. These compounds were converted into 3-substituted xanthines by treatment with aqueous alkali or by heating in formamide. The present reaction was compared with an analogous reaction, formation of 9-substituted hypoxantines via 7-aminooxazolo[5,4-d]pyridimine derivatives, and the difference in the reaction course was discussed in terms of the effect of substituents on the stability of oxazolopyrimidine intermediates.
The Jacobsen Reaction of Iodopseudocumenes and Related Compounds. Orientation in the Iodination of Halopseudocumenes
Authors: Suzuki Hitomi , Sugiyama Takashi
Published: July 2006

The Jacobsen reaction of iodopseudocumenes and related compounds was investigated. Both 3- and 5-iodopseudocumenes gave essentially the same product which consisted of 3,5-diiodopseudocumene (VI, 53%), 3,6-diiodopseudocumene (VII, 44%) and 5,6-diiodopseudocumene (VIII, 3%). The unexpected result was interpreted in terms of a mechanism involving a prior interconversion of the 3- and 5-iodo isomers followed by the ordinary process of aromatic disproportionation. 6-Iodopseudocumene gave VII as the major product. By prolonged contact with concentrated sulfuric acid, VI and VIII were found to undergo partial isomerization to give VII. Early structural assignment by Smith and Moyle for two diiodopseudocumenes was revised. Reactions of 4- and 5-iodohemimellitenes with sulfuric acid gave 4,6-diiodohemimellitene (XII) as the major product. A diiodohemimellitene melting at 114°C was found to be a mixture of XII and 4,5-diiodohemimellitene (XI), the former being predominant. Isomeric chloro-, bromo-, and iodopseudocumenes were iodinated with iodine-periodic acid dihydrate and the orientation in the products was determined.
Syntheses of Diiodo and Triiodo Derivatives of 1,2,3-Trimethylbenzene (Hemimellitene) and 1,2,4-Trimethylbenzene (Pseudocumene). A Convenient Use of Polyiodo Derivatives for the Characterization of Polyalkylbenzenes and Their Derivatives
Authors: Suzuki Hitomi , Haruta Yasuhiro
Published: July 2006

A complete set of diiodo and triiodo derivatives of 1,2,3-trimethylbenzene and 1,2,4-trimethylbenzene has been prepared and their physical properties are recorded. Use of polyiodo derivatives as a means for characterizing polyalkylbenzenes and their derivatives has been proposed.
Optically Active Triptycenes, V. Synthesis, Optical Resolution and Absolute Configuration of 2,7-Disubstituted Triptycenes.
Authors: Kuritani Masaaki , Sakata Yoshiteru , Ogura Fumio , Nakagawa Masazumi
Published: July 2006

2,7-Dicarboxytriptycene retaining C2-axis of symmetry was synthesized from 1,5-dichloroanthraquinone. Optical resolution of the triptycene afforded (+)- and (−)-enantiomers. The absolute configuration of (+)-2,7-dicarboxytriptycene was determined as 1R,6R by chemical correlation with (+)-2-methoxy-7-methoxycarbonyltriptycene which has 1R,6S configuration as confirmed by chemical transformation and X-ray structure analysis using the Bijvoet method. Starting from (+)-2,7-dicarboxytriptycene, a series of 2,7-disubstituted triptycenes having 1R,6R configuration has been prepared.
Optically Active Triptycenes. IV. Synthesis of Optically Active 2- or 5-Substituted 7-Carboxytriptycenes
Authors: Sakata Yoshiteru , Ogura Fumio , Nakagawa Masazumi
Published: July 2006

Starting from anthraquinone-1-carboxylic acid (I), 2-methoxy- and 5-methoxy-7-carboxytriptycenes (VIIa and VIIb) have been synthesized. Optical resolution of the triptycenecarboxylic acids with brucine afforded (+)-VIIa and (+)-VIIb. The absolute configuration of (+)-VIIa was determined to be 1R,6R by the chemical correlation with (+)-2,5-dimethoxy-7-methoxycarbonyltriptycene. From a comparison of the CD spectrum of (+)-5-methoxy-7-carboxytriptycene (VIIb) with that of (+)-2-acetoxy-5-methoxy-7-methoxycarbonyltriptycene (XIIIb), 1R,6R absolute configuration was assigned to (+)-VIIb. (+)-2-Hydroxy-5-phenylazo-7-carboxytriptycene (XIIa) was derived from (+)-VIIa. (+)-2-Chloro- and (+)-5-chloro-7-carboxy triptycenes (XVIIIa and XVIIIb) have been prepared from 5-chloro- and 8-chloro-1-carboxyanthraquinones (XIVa and XIVb). The absolute configuration of (+)-XVIIIa was determined to be 1R,6R by the chemical correlation with (−)-VIIa via (+)-2-chloro-5-methoxytriptycene (XIX).
The Ion-exchange Behavior of the Ammonium Ion on Crystalline Zirconium Phosphate
Authors: Hasegawa Yoshitsugu , Aoki Hisashi
Published: July 2006

The ion-exchange behavior of the ammonium ion on crystalline zirconium phosphate (c-ZrP) was studied by pH titration and X-ray powder diffraction. The ion-exchange capacity of c-ZrP was 4.4 meq/g in an acidic solution and 6.6 meq/g in an alkaline solution. At an exchange of 66% the Zr(NH4PO4)1.33(HPO4)0.67·H2O phase was present and at an exchange of 100% Zr(NH4PO4)2·H2O phase was present. The forward and backward titration curves exhibited a hysteresis loop. This results from the presence of the different phases in the titration of each direction. Through the ion-exchange cycle, the crystallinity of c-ZrP was maintained.
The Photochemistry of 2-Quinolinecarbonitriles. I. The Photochemical Reactions of 2-Quinolinecarbonitriles with Alcohols, Ethers, or Carboxylic Acids
Authors: Hata Norisuke , Ono Isao , Matono Satoru , Hirose Harutoshi
Published: July 2006

The photochemical reactions of 2-quinolinecarbonitriles with alcohols, diethyl ether, or aliphatic carboxylic acids in an atmosphere of oxygen or nitrogen were found to result in the replacement of the cyano group by 1-hydroxyalkyl, 1-ethoxyethyl, or alkyl group. However, the irradiation of 2-quinolinecarbonitrile in an alcoholic solvent except for the case of tert-butyl alcohol under a nitrogen atmosphere gave an unidentified substance (probably, a certain triazapentaphene) in addition to the photosubstitution product. The photoinduced substitution reaction found in the present experiment was revealed to proceed through the excited singlet state of 2-quinolinecarbonitrile, whereas the lowest triplet state was responsible for the formation of an unidentified substance in a deaerated alcohol.