bluuebunny/crossref_metadata_2025 huggingface dataset:
Conformation and Circular Dichroism of Several N-Acyl-l-prolines
Authors: Nishihara Hisao , Nishihara Koji , Uefuji Tamio , Sakota Naokazu
Published: July 2006

NMR and CD studies were carried out for acetyl-l-proline, isovaleroyl-l-proline, isobutyroyl-l-proline, pivaloyl-l-proline and benzoyl-l-proline. It was found that N-acetyl-l-proline has two rotational isomers about the amide bond, S-trans and S-cis conformers even at room temperature, and that the population of the former is greater than that of the latter except for pivaloyl-l-proline, which consists only of the S-trans conformer. The two isomeric N-acyl-l-prolines showed different CD peaks of opposite sign associated with the n→π* transition of the amide group.
Studies of Enamines. VI. The Formation of New Michael Type Adducts and Pyrrolizine Compounds in the Reaction of Enamines with Pyrrole
Authors: Tashiro Masashi , Kiryu Yoko , Tsuge Otohiko
Published: July 2006

While the reaction of 1-(1-pyrrolidinyl)propene (1a) and -1-butene (1b) with pyrrole (2) under mild conditions afforded the Michael type N,N–1:1 adducts 3, under forcing conditions enamines 1 reacted with 2 to give the Michael type C,N–1:1 adducts 4, accompanied with pyrrolizine compounds 5. It has been shown that the pyrrolizine 5 was formed via the cycloaddition reaction of 1 with an azafulvene intermediate arising from 4 by the elimination of pyrrolidine.
The Molecular Vibrations and Rotational Isomerism of Chloro(cWoromethyl)silane
Authors: Sera Keiichi
Published: July 2006

The infrared spectra of chloro(chloromethyl)silane, ClCH2SiH2Cl, and its deuterated species, ClCH2SiD2Cl, have been measured in the gaseous, liquid, and crystalline states. The Raman spectra have also been measured in the liquid state. The vibrational spectra have shown that two rotational isomers coexist in the gaseous and liquid states, while only one isomer persists in the crystalline state. The fundamental vibrations have been assigned for each isomer. The product rule, the calculation of the skeletal frequencies, and the band contours have indicated that the isomer persisting alone in the crystalline state is the trans form and that the other isomer is the gauche form. The solvent effects of the spectra have shown that the gauche form is more polar than the trans form. The normal vibrations have been calculated in a modified Urey-Bradley force field, and the force constants have been adjusted to predict well the observed frequencies for the isomers of both the parent and its deuterated species.
Photolysis of Ethylene at 1470 Å
Authors: Hara Hiroshi , Kodama Kenji , Tanaka Ikuzo
Published: July 2006

Relative quantum yields of the primary processes in the photolysis of ethylene at 1470 Å were determined. No energized vinyl radical was found. Photolysis in the presence of nitric oxide suggests that about 20% of 1-butene is produced through the direct addition reaction of excited ethylene to ground state ethylene, C2H4*+C2H4→1-C4H8.
The Separation and Determination of Chromium(VI) by Reducing Elution Using Anion Exchange Resin and Sodium Sulfite
Authors: Yamashige Takashi , Izawa Hirofumi , Shigetomi Yasumasa
Published: July 2006

The reducing elution of chromium(VI) by anion exchange using sodium sulfite has been investigated. Chromium(VI) is reduced to chromium(III), which is eluted quickly and easily separated from interfering substances by colorimetry using diphenylcarbazide.
The Solubility Parameter of Tetrasulfur Tetranitride
Authors: Hamada Shuichi , Kudo Yoshiyuki , Kawano Masako
Published: July 2006

The solubilities of tetrasulfur tetranitride in thirteen organic solvents were measured. The solubility parameter of tetrasulfur tetranitride was estimated from the solubilities and its deduced activity to be 13·7 at 25 °C; we assumed it to be regular.
Composition of Single Crystal of Iron Sulfide Grown by Normal Freezing
Authors: Ametani Kohei , Takahashi Tatsuo
Published: July 2006

The composition of a single crystal of iron sulfide was determined as a function of position along the growth axis using atomic absorption spectrophotometry. The observed composition was consistent with the phase diagram for the iron-iron sulfide pseudo binary system and the results of physical measurements.
The Syntheses of Several Pyrimido[4,5-e][1,2,4]triazines
Authors: Sugimoto Takashi , Matsuura Sadao
Published: July 2006

A new synthetic method for some derivatives of pyrimido[4,5-e][1,2,4]triazine, using 5-nitrosopyrimidines as the starting materials, was studied. That is, the condensation of 5-nitrosopyrimidin-2,4,6-trione and its methyl derivative with amino- or alkylamino-guanidine gave several 3-aminopyrimidotriazin-6,8-diones.
Cationic Arylation. VIII. Reactions of Benzenediazonium Tetrafluoroborate with Some Sulfur Compounds
Authors: Kobayashi Michio , Minato Hiroshi , Fukui Junko , Kamigata Nobumasa
Published: July 2006

Reactions of benzenediazonium tetrafluoroborate (I) with thioanisole in acetonitrile yielded dimethylphenylsulfonium tetrafluoroborate, diphenyl sulfide, methylthiobiphenyls and acetanilide. Reaction of I with cyclohexene yielded 1-cyclohexylcyclohexene and cyclo-hexyl phenyl ether. Reactions of I with dimethyl sulfide yielded trimethylsulfonium tetrafluoroborate and thioanisole. Mechanisms of these reactions were discussed in terms of the attack of phenyl cation toward the lone electron pair of sulfur atoms and the benzene electrons.
Reaction of Benzylic Chlorides with Hexamethylphosphoric Triamide
Authors: Arimatsu Seiji , Yamagughi Ryohei , Kawanisi Mituyosi
Published: July 2006

Benzyl chloride was converted into benzyldimethylamine (1), dibenzylmethylamine (2), and benzylpentamethylphosphoric triamide (3), when it was heated in hexamethylphosphoric triamide (HMPT). Diphenylmethane (4), benzhydrylmethylamine (5), and benzophenone methylamine (6) were obtained when benzhydryl chloride was used in place of benzyl chloride. Triphenylmethyl chloride afforded triphenylmethane (7) as the sole isolable product.
Reactions of 1-Azaazulan-2-one and Its 3-Substituted Derivatives
Authors: Toda Takashi , Ryu Shoji , Hagiwara Yohichi , Nozoe Tetsuo
Published: July 2006

Chemical properties of l-azaazulan-2-one (I) and its 3-substituted derivatives such as 3-acetyl, 3-cycloheptatrienyl and 3-ethoxycarbonyl were investigated. It was shown that the electrophilic substitution reactions take place at the 3-position, replacement of the substituents occuring in some cases by the reactions with cationoid reagents. The Beckmann rearrangement, Curtius rearrangement, Hofmann degradation reaction, Stevens-McFadyen reaction, etc. of these compounds are described.
Analysis of Metals by Solid-Liquid Separation after Liquid-Liquid Extraction. Spectrophotometric Determination of Some Metals by Extraction of Metal Complexes with Molten Naphthalene
Authors: Fujinaga Taitiro , Satake Masatada , Yonekubo Tatsuo
Published: July 2006

A procedure is described for the spectrophotometric determination of metals after extraction with molten naphthalene. Some metal ions react in aqueous solution with complex-forming reagents such as oxine, 2-methyl-oxine, dimethylglyoxime or α-benzil dioxime to form water-insoluble complexes in certain pH ranges, the complexes being easily extracted into molten naphthalene. The extracted mixture of metal complex and naphthalene is dissolved in dimethylformamide and the amount of each metal is determined spectrophotometrically. The working range of metal ion concentration and effect of various factors such as pH, amount of reagent and naphthalene were studied, and the molar absorptivity, sensitivity and relative standard deviation evaluated.
Chlorination of Methylcyclohexane in Molten Salt Media
Authors: Kikkawa Sh\={o}ichi , Hayashi Takatoshi , Nomura Masakatsu , Otsu Noboru
Published: July 2006

The chlorination of methylcyclohexane in several molten metal chloride mixtures (ZnCl2/KCl/NaCl, CuCl/ KCl/NaCl, AlCl3/KCl/NaCl, and CuCl2/KCl/NaCl) has been carried out, using nitrogen gas as a diluent, at three levels of temperature (250, 350, and 450°C. The reactions in both ZnCl2 and CuCl melts were studied extensively, the former representing the molecular-type melt and the latter standing for the partially-ionic-type one. These reactions gave 1-, 2-, 3-, and 4-chloro-methylcyclohexanes and 1-, 3-, and 4-methylcyclohexenes as primary products, along with smaller amounts of toluene and methylcyclohexadiene. The formation of these olefins were interpreted by the subsequent elimination (by a carbonium-ion mechanism) of HCl catalytically enhanced by these melts from the methyl-chlorocyclohexane derivatives. The difference observed in the product distributions between ZnCl2 and CuCl melts was also explained by the studies of the effect of hydrogen chloride produced in these reactions over molten salts.
Pressure Effect on the Isomerization Velocities of β-[Co(edda)(tn)]+ and β-[Co(edda)(en)]+ in Solution
Authors: Kitamura Yoichi
Published: July 2006

The rates of the isomerization of β-[Co(edda)(tn)]+ and β-[Co(edda)(en)]+ to the α-isomers in a 0.2 M Na2CO3–0.2 M NaHCO3 buffer solution have been measured under pressures of 1, 1000, 2000, and 3000 kg cm−2. The activation volumes have been found to be 14.7 and 20.0 ml mol−1 respectively. It may be concluded that these reactions proceed through the SNl CB mechanism.
Circular Dichroism of trans-Dichlorocobalt(III) Complexes with Chiral 1,2-Diamines
Authors: Yano Shigenobu , Saburi Masahiko , Yoshikawa Sadao , Fujita Junnosuke
Published: July 2006

The circular dichroism (CD) spectra of trans-dichlorobis(diamine)cobalt(III) complexes were measured in methanol solution in the 700–200 nm region, where the diamines have the general formula of NH2CH(R)CH2NH2(R=isopropyl, isobutyl, sec-butyl, benzyl and phenyl) and belong to the S configuration except the phenyl-substituted one. The spectra are essentially the same as thq spectrum of the (S)-propylenediamine ((S)-pn; R= methyl) complex, except for the (R)-C-phenylethylenediamine ((R)-phenen) complex. The variation of the C-substituted alkyl groups has hardly any influence on the CD of the trans-[CoCl2(diamine)2]+ type complexes, demonstrating that the vicinal contribution from the C-substituents can be disregarded in these compounds. The trans-[CoCl2((R)-phenen)2]+ ion shows a CD pattern differing significantly from that of the trans-[CoCl2((R)-pn)2]+ ion in the first absorption band region, suggesting the significance of the vicinal effect due to the C-substituted phenyl group. The CD curve of trans-[CoCl2((−)D-stien)2]+ ion (stien=stilbenediamine) was found to be antimeric to that of the (R)-phenen complex. Taking into account the anomalous vicinal effect of the phenyl groups, the absolute configuration of the (−)D-stien was assigned to the (S,S) configuration.
Preparation of Phorone
Authors: Nakada Yasuo , Yura Yasuo , Murayama Keisuke
Published: July 2006

A new method for preparation of 2,6-dimethylhepta-2,5-dien-4-one (4; phorone) from isobutene and carbon tetrachloride is described. A redox addition of carbon tetrachloride to isobutene in the presence of ferric chloride, benzoin, and diethylamine hydrochloride yielded 3-methyl-1,1,1,3-tetrachlorobutane (1). 2,6-Dimethyl-2,4,4,6-tetrachloroheptane (2) was obtained by the addition of 1 to isobutene or the twofold addition of carbon tetrachloride to isobutene. Treating 2 with ethanolic potassium hydroxide gave 2,6-dimethylhepta-1,5-dien-3-yne (3). Hydration of 3 by treating with methanolic boron trifluoride in the presence of mercuric oxide and with aqueous sulfuric acid gave 4.
The Effects of Phosphorus Ligands on the Stereoselectivity of the Nickel-catalyzed Dimerization of Norbornadiene
Authors: Yoshikawa Susumu , Kiji Jitsuo , Furukawa Junji
Published: July 2006

The effects of phosphorus ligands on the stereoselectivity of the nickel-catalyzed 2+2 cyclodimerization of norbornadiene have been studied. The electronic factor, νCO(A1), of Ni(CO)3L (where L is the ligand) is correlated with the ratio of the exo-trans-exo (X-t-X) to the exo-trans-endo (X-t-N) isomers of the product, but no simple correlation is apparent between the steric parameter and the selectivity. A three-coordinated Ni(0) species is proposed as the intermediate. The values of ΔHX-t-X\eweq−ΔHX-t-N\eweq and ΔSX-t-X\eweq−ΔSX-t-N\eweq are large and negative.
Compounds Related to Acridine. XIII. Reactions of 9-Vinyl- and 9-Ethynylacridine with C,N-Diarylnitrones
Authors: Tsuge Otohiko , Torii Akiyoshi
Published: July 2006

The reaction of 9-vinylacridine (1) with C,N-diarylnitrones (3) in xylene under reflux afforded 5-(9-acridinyl)-2,3-diarylisoxazolidines (4) and/or 9-acridinyl styryl ketones (5). On heating isoxazolidines 4 were readily converted into the styryl ketones 5 with the elimination of anilines: this is a new type of thermal decomposition of isoxazolidine ring. However, thermal decomposition of 3-(9-acridinyl)-2,5-diarylisoxazolidines (9) which were prepared from N-(9-acridinylmethylene)aniline N-oxide (7) and styrene (8), did not observed. On the other hand, the reaction of 9-ethynylacridine (2) with nitrones 3 in ethanol under the influence of hydrochloric acid proceeded smoothly to give the reversed 4-(9-acridinyl)-4-isoxazolines (11), which on heating were converted into the corresponding 4-oxazolines 12.
The Crystal Structure of the Trinuclear Complex, [Cu3{(C2H5)2N(CH2)2NH(CH2)3O}2(OH)2](ClO4)2
Authors: Matsumoto Naohide , Nishida Yuzo , Kida Sigeo , Ueda Ikuhiko
Published: July 2006

The structure of the trinuclear complex, formed from N,N-diethyl-N′-(3-hydroxypropyl)ethylenediamine and copper(II) perchlorate, has been determined from three dimensional X-ray diffraction data. The crystals are monoclinic with the space group P21/c. The cell dimensions are a=7.759(6), b=13.21(1), c=15.00(1) Å and β=103.95(6)°. The unit cell contains two molecules and the molecule has a centre of symmetry. The structure has been determined by the heavy atom method and refined by the block diagonal least squares method to give R=6.83% for 1368 observed reflections. Three copper atoms are arrayed on a straight line, the separations being 2.902 Å. The geometry around the two end copper atoms is best described as a slightly distorted tetragonal pyramid. The central copper atom has a square planar environment.
Study of Cholesteryl Formate and Cholesteryl Octanoate by Means of Thermal Analytic Microscopy with a Thermoelement
Authors: Sasaki Kunihisa Kazuko , Hagiwara Seiichi
Published: July 2006

A simple apparatus using a thermoelement was constructed for thermal analytic microscopy and the phase transitions of cholesteryl formate and cholesteryl octanoate were studied. The isotropic-cholesteric transition of cholesteryl formate and the cholesteric-smectic transition of cholesteryl octanoate were observed microscopically but not thermally. Upon slow cooling cholesteryl octanoate gives large spherulites with a cholesteric focal conic texture. The spherulites are optically negative. They give rise to the vortices which turn to smectic reeled yarns in specimens with appropriate thickness. The solar spectrum which appears at the cholesteric-smectic transition of cholesteryl octanoate was observed repeatedly, namely, blue, yellow, red, blue, etc. A melt recrystallized sample of cholesteryl formate forms a block similar to a sphere in the thermal cell. Both solid phases of cholesteryl formate and octanoate grow radially in the microscopic cell plates.
Physico-Chemical Properties of Aqueous Solutions of Cn−1H2n−1OCH2COONa
Authors: Hato Masakatsu , Shinoda K\={o}z\={o} , Miyagawa T\={o}ru
Published: July 2006

Properties of aqueous solutions of surfactants, Cn−1H2n−1OCH2COONa (n−1=12–18), which may be nontoxic, non-allergic and bio-degradable, have been studied. The Krafft points in aqueous solutions of these surfactants are close (+8.5–−1.5 °C) to those of the corresponding fatty acid soaps RnCOONa. The critical micelle concentrations are also close to those of corresponding fatty acid soaps in spite of the introduction of an oxygen atom in the hydrocarbon chain. A study of the effect of water hardness on the solubility revealed that this type of surfactant is, unlike soap, soluble in town water (hardness 4°) in the presence of equal weight of tripolyphosphate.
The Microwave Spectra of Sulfur Tetrafluoride in the Excited Vibrational States. The Vibrational Assignment for ν4 and ν9
Authors: Inoue Hiroshi , Naruse Akio , Hirota Eizi
Published: July 2006

The vibrational satellites of SF4 have been observed for the two lowest bending modes, ν4 and ν9. The relative intensities which were observed are consistent with the vibrational assignment of Frey et al. but are incompatible with Levin’s assignment. Consideration of the Coriolis interaction between the two modes lead to the same conclusion. The centrifugal distortion constants are evaluated and are compared with the observed.
Trifluoroacetylation at the 3 Position of 1-(2-Aminophenyl)-2,5-dimethylpyrrole in Trifluoroacetic Acid. Possible Remote Control of an Amino Group in Electrophilic Substitution
Authors: Imuro Kimie , Hanafusa Terukiyo
Published: July 2006

Spontaneous trifluoroacetylation at the β position of the pyrrole ring in 1-(2-aminophenyl)-2,5-dimethylpyrrole (1) was observed in trifluoroacetic acid. The half-life of the reaction was about 3.5 h at 25 °C. This unexpected result might be explained in terms of the 1,5-participation of the amino group in the electrophilic substitution reaction.
An Observation of Compensation Effects between Enthalpy and Entropy Changes in the Interaction of Nickel-2,2′-bipyridine Complexes with Olefins
Authors: Yamamoto Akio , Yamamoto Takakazu
Published: July 2006

Compensation effects in the thermodynamic parameters ΔH° and ΔS° in the coordination of olefins with Ni(bpy) and NiR2(bpy) (bpy=2,2′-bipyridine) and in the kinetic parameters ΔH\eweq and ΔS\eweq in reactions of NiR2(bpy) with olefins have been observed; factors governing these compensation effects are discussed.
Effect of Hydroxylation on the Thermal Reactivities of Fluorapatite and Chlorapatite
Authors: Monma Hideki , Kanazawa Takafumi
Published: July 2006

Thermal self-decomposition of hydroxyapatite was notably suppressed by partial fluorination or chlorination. The volatility of halogen from fluorapatite and chlorapatite was reduced by the incorporation of hydroxide ions in the apatites. The reactivities of fluor-hydroxyapatite and chlor-hydroxyapatite with silica increased with increasing hydroxide content, which resulted in an increase in the halogen volatility.
The Reaction of the Butenyl Grignard Reagent with Trimethylchlorosilane
Authors: Sakurai Hideki , Kudo Yoshihiko , Miyoshi Heiichi
Published: July 2006

The reaction of trimethylchlorosilane with the butenyl Grignard reagent prepared from either 3-chloro-1-butene or 1-chloro-2-butene yielded trans-2-butenyltrimethylsilane, cis-2-butenyltrimethylsilane and 1-methyl-2-propenyltrimethylsilane, approximately in the ratio of 30/20/50. Structures of these isomeric butenylsilanes were elucidated by NMR and IR spectra.
The Preparation, Infrared Spectra, and Thermal Stability in the Solid State of Nickel(II) Complexes with edda-type Polyamino Carboxylic Acids
Authors: Hirako Ichiro , Murakami Tasuku , Hatano Masahiro
Published: July 2006

Some nickel(II) complexes with optically active ethylenediamine-N,N′-diacetic acid(edda)-type polyamino carboxylic acids were prepared. Their electronic and infrared spectra and thermogravimetric curves were measured in the solid state. The stretching frequencies of the coordinated carboxylate group and the thermal stability of these complexes in the solid state were quite different from those of bis(amino acidato) complexes.
The X-Ray Structure of the (+)589-cis(O)trans(Nα)cis(Nδ)-Bis(l-ornithinato)cobalt(III) Complex
Authors: Nakayama Yasuji , Ooi Shun’ichiro , Kuroya Hisao
Published: July 2006

(+)589-Bis(l-ornithinato)cobalt(III) nitrate monohydrate was isolated by ion-exchange chromatography from a reaction mixture of trinitratotriamminecobalt(III) with l-ornithine at pH 9, and was assigned to the cis-(O)trans(Nα)cis(Nδ) isomer on the basis of the absorption and circular dichroism spectra. Then, the geometry of the complex was confirmed by X-ray structure analysis. The red crystal is orthorhombic, with these cell dimensions: a=14.380, b=16.493, and c=6.787 Å. The space group is P212121, and Z=4. The crystal structure was solved by the Patterson and Fourier techniques and was refined by the least-squares method to R 0.099. The Co atom is surrounded by 2 O and 4 N atoms, the former being in cis positions. Each of the l-ornithinato ligands assumes the facial coordination, and the complex cation has an approximate two-fold axis by which the ligand are correlated.
The Crystal Structure of α-K8SiW11O39·13H2O
Authors: Matsumoto Kazuko Y , Sasaki Yukiyoshi
Published: July 2006

α-K8SiW11O39·13H2O is cubic with the space group P\bar43m and a=10.654(1) Å; Dm=4.40 g cm−3, Dx=4.42 g cm−3 for Z=1. The crystal contains a discrete SiW11O398− ion, which is almost identical to α-SiW12O404− anion in shape and in size but one tungsten atom and the exterior terminal oxygen atom are absent. The position of the vacant hole could not be located because of the seemingly high symmetry of Td of the polyanion caused by the orientational randomness of the anions. The silicon atom at the center of the polyanion lies on the origin of the cubic lattice and the potassium cations linking α-SiW11O398− ions are at the middle points of adjacent polyanions.
Color and Structural Changes of Bis(hexamethylenetetramine)cobalt(II) and nickel(II) Complexes in the Course of Thermal Dehydration in Solid State
Authors: Nagase Kenzo , Yokobayashi Hiroko , Sone Kozo
Published: July 2006

The stoichiometry of thermal dehydration of MX2(hmta)2·nH2O (hmta=hexamethylenetetramine; X= Cl−, Br−, I−, NO3−, NCS−; n=4–10) was established by the TG-DTA methods. The nature of the structural changes caused by complete or partial dehydration was studied on the basis of the accompanying changes in the electronic and vibrational spectra. Anions and hmta in general get into the coordination sphere with a decrease in the number of the coordinated water, but the bulky and weakly basic amine often gets coordinated in the last stage.
Study of the Synthesis of Histidine Peptides. II. Use of Nim-Tosylhistidine Derivatives in Conventional Solution Synthesis of Peptides
Authors: Fujii Toshiyuki , Kimura Terutoshi , Sakakibara Shumpei
Published: July 2006

His–Gly and Ala–His–Gly were synthesized by the conventional solution methods using various Nα-protected-Nim-tosyl-l-histidines as the key intermediates, and handling conditions of these His(Tos)-derivatives were examined. During treatment of an Nps-peptide with HF, the formation of a strongly photosensitive by-product was observed when anisole alone was used as the scavenger, however the side reaction was completely suppressed when skatole was added to the reaction mixture. In order to evaluate the usefulness of these His(Tos)-derivatives in general peptide synthesis, TRH and LH–RH were synthesized, and both products were obtained in pure form without any difficulty. Thus, it can be emphasized that the use of these His(Tos)-derivatives is efficient and convenient for introducing His-residues into peptides even in solution procedures.
Stereochemistry of the C and D Rings of C-Nor-D-homosteroids. IV. The Relative Stabilities and NMR Spectra of 17-Substituted C/D trans- and cis-Fused Etiojervanes
Authors: Masamune Tadashi , Murai Akio , Nishizakura Kouichi , Orito Takako , Numata Satoshi , Sasamori Hiroshi
Published: July 2006

(1) The relative stabilities between 17-substituted C/D trans- and cis-fused 11-oxoetiojervanes were investigated by treatment of both or either one of these 12-epimeric compounds under equilibrating conditions. The equilibrium ratios thus obtained were estimated qualitatively in terms of the configuration and bulkiness of substituent(s) at C17. (2) The chemical shifts of 19- and 18-methyl protons in a number of etiojervanes were examined collectively. The “principle of additivity” holds satisfactorily for the 19-methyl protons of all etiojervanes, with two exceptional cases, irrespective of the configuration at C12 and also for the 18-methyl protons of 12β-etiojervanes. However, the principle is not applicable for the latter protons of 12α-etiojervanes, suggesting that the D ring would take different conformations depending on the 17-substituents.
Foamy Complex Formation for Removing and Recovering of Heavy Metal Ions in Dilute Solutions with N-Monodecanoyl Diethylenetriamine
Authors: Izumi Gaku , Sato Makoto , Shoji Sakae , Oikawa Kanenao
Published: July 2006

In order to highly selectively remove and recover heavy metals, usually harmful, from wastewater, a modified foam-separating method using a fatty compound, i.e.  N-monodecanoyl diethylenetriamine, was investigated on real and model wastewater, containing several kinds of metals. This agent forms soluble and foamy complexes with the metals.
3C-NMR Study of Aerosol OT in Chloroform
Authors: Ueno Masaharu , Kishimoto Hiroshi , Kyogoku Yoshimasa
Published: July 2006

The dynamic structure of Aerosol OT molecules in micellar state was studied by measurements of 13C-NMR spin-lattice relaxation time (T1) and the effect of a lantanide shift reagent Yb(fod)3 in chloroform at 25 MHz and 40°C. The results were analyzed on the basis of the conformation and segmental motions of Aerosol OT molecules in micellar state, with the following conclusions: Aerosol OT molecules in the micellar state associate with each other by the polar head groups; their hydrocarbon chains are flexible; the mobility of side chain is restricted to a greater extent than that of the main chain; carbonyl carbon-(2′) is located nearer to the polar group than carbon-(2) in steric conformation.
Nature of Catalytically Active Sites over Solid Acids. I. Selective Poisoning of Lewis Acid Sites on Silica–Alumina with Pyridine and Its Application to Olefin Polymerization
Authors: Mizuno Koichi , Ikeda Masanori , Imokawa Toshiaki , Take Jun-ichiro , Yoneda Yukio
Published: July 2006

When pyridine chemisorbed on silica–alumina was evacuated at 350°C, the 1460 cm−1 band due to Lewis-bound pyridine (LPY) remained while the 1540 cm−1 band due to Brønsted-bound pyridine (BPY) completely disappeared. This disappearance of the BPY band was revealed to accompany a loss of the Brønsted acid sites themselves besides their liberation. However, the lost Brønsted acid sites were regenerated by allowing the sample to stand overnight at 110°C. Thus, strong Lewis acid sites of silica–alumina were able to be selectively poisoned by pyridine without any damage to the Brønsted acid sites. By poisoning catalysts in situ by controlled amounts in this way, the nature of the active site was investigated for polymerization of propylene or cis-2-butene at a low temperature of 30 °C. The initial activity declined sharply as the extent of pyridine poisoning of the Lewis acid sites increased. Therefore, it was concluded that strong Lewis acid sites (25–30% of the total Lewis acid content) were active in polymerization over silica–alumina.
Dielectric Study of the Intermolecular Association of Alcohols in Solutions of Benzene
Authors: Singh Buta , Vij J K
Published: July 2006

The relative permittivity at 1 MHz, the refractive index at the wavelength of sodium D-line and density of the nine alcohols, 1-propanol (A), 2-propanol (B), 1-butanol (C), 2-methyl-1-propanol (D), 1-pentanol (E), 1-hexanol (F), 1-heptanol (G), 3-methyl-2-hexanol (H), 3-methyl-3-hexanol (I), have been measured at 25 °C in benzene in the entire concentration range. The measurements for 1-dodecanol (J) have been made in dilute solutions only. The dipole moments of these molecules in dilute solutions, using Higasi’s equation, and the apparent dipole moment for various solute concentrations, using Kirkwood-Fröhlich equation, have been calculated. The results suggest that at low concentrations the alcohols associate to form weakly polar multimers. At high concentrations and in pure liquids, the isomers in which the hydroxyl group is relatively free, favour the formation of highly polar multimers, whereas the isomers in which the hydroxyl group is sterically blocked by the methyl group, favour the formation of closed or ring dimers having low dipole moment.
Isomerization of the (d-Aspartato)(l-2,4-diaminobutyrato)cobalt(III) Complex
Authors: Watabe Masatoshi , Kawaai Shigeji , Yoshikawa Sadao
Published: July 2006

The isomerization of two of the three possible geometrical isomers for the (d-aspartato)(l-2,4-diaminobutyrato)cobalt(III) complex afforded the residual third isomer which has not here to fore been obtained. The equilibrium mole fractions of these isomers in water in the presence of activated carbon were found for d-cisO5cisN5, d-transO5transN5, d-fac to 0.68, 0.11, 0.21, respectively. As the two ligands coordinated are considered to involve no intermolecular hydrogen bonding or steric hindrance, the relative positions of the six coordinated atoms around a cobalt atom may cause these unequal isomer ratios. These isomerisms are dealt with by means of a network of firstorder reversible reactions and the relative values of the rate constants are determined.
Conditions for the Formation of Compounds Consisting of BaO and Fe2O3 from Aqueous Suspensions
Authors: Kiyama Masao
Published: July 2006

Suspensions containing either iron(III) hydroxide or hydroxide oxide and barium ions were subjected to autoclaving at various temperatures from 100 to 300 °C, and the properties of the resulting products were studied. A ferromagnetic precipitate, BaO·6Fe2O3, consisting of hexagonal plate-like particles, was obtained by suitable combination of temperature, kind and particle size of iron(III) hydroxide oxide, and concentration of Ba(OH)2. Nonferromagnetic precipitates, BaO·4.5Fe2O3 and BaO·2Fe2O3, were also formed depending on the conditions. The mechanism of their formation is discussed. The magnetic properties of the BaO·6Fe2O3 precipitates are investigated.
The Crystal Structure of (+)350-Diammine-N,N,N′-trimethylethylenediamineplatinum(II) Di-μ-(+)-tartrato(4-)bis(antimonate(III)) Monohydrate
Authors: Yokoho Keiji , Matsumoto Keiji , Ooi Shun’ichiro , Kuroya Hisao
Published: July 2006

X-Ray structure analysis of the title compound has revealed that the asymmetric secondary nitrogen center in the complex cation has the S absolute configuration. The crystals are orthorhombic, with the space group P212121and with Z=4 in a unit cell with dimensions of: a=18.783(6), b=14.138(4), and c=8.473(2)Å. The crystal structure has been determined from three-dimensional diffractometer data and refined by the least-squares method to R of 0.030 for 1971 independent reflections with I>3σ(I). The Pt atom has a square-planar coordination by four N atoms, and the methyl group bonded to the secondary nitrogen is equatorial with respect to the chelate ring. Each complex cation is surrounded octahedrally by six di-μ-(+)-tartrato(4-)-bis(antimonate(III)) anions.
Isomers of trans-Dichlorocobalt(III) Complex with (2S,10S)-2,10-Diamine-4,8-diazaundecane
Authors: Goto Masafumi , Makino Tadashi , Saburi Masahiko , Yoshikawa Sadao
Published: July 2006

A novel complex, trans (R,S)-[CoCl2((2S,10S)-Me2-2,3,2-tet)]ClO4((2S,10S)-Me2-2,3,2-tet=(2S,10S)-4,8-diazaundecane-2,10-diamine) was prepared from the trans(R,R) isomer in basic methanol. The configuration of the trans(R,S) isomer was determined from the PMR and CD evidences. The equilibrium ratio of the R,S and R,R isomers in basic methanol was estimated to be 7.6±0.3: 1 (ΔG298=1.20±0.03 kcal/mol), the former being in preference to the latter.
Precise Measurement of Ionic Diffusion Coefficients with a Hanging Mercury Drop Electrode
Authors: Ikeuchi Haruko , Fujita Yoshimi , Iwai Kyoichi , Satô Gen P
Published: July 2006

The diffusion coefficient and the product of the charge number of electrode reaction n and the concentration of depolarizer c can be determined simultaneously from the time dependence of the diffusion limiting current observed at a spherical electrode of known size. Nearly ideal spherical diffusion was realized by means of a mercury drop electrode hanging from the tip of a fine glass capillary (0.2 mm, outer diameter) which was kept at constant size by adjusting the mercury head. The diffusion coefficients of thallium(I), cadmium(II), bismuth(III), and hexamminecobalt(III) ions in 0.1 mol dm−3 potassium nitrate aqueous solutions were determined at 25 °C. The experimental nc values agreed with the corresponding known values within 3%.
A Facile Synthesis of 2,5-Disubstituted Tetrazoles by the Reaction of Phenylsulfonylhydrazones with Arenediazonium Salts
Authors: Ito Suketaka , Tanaka Yumo , Kakehi Akikazu , Kondo Ken-ichi
Published: July 2006

2,5-Disubstituted tetrazoles are obtained in good yields by the reaction of phenylsulfonylhydrazones of aromatic aldehydes (and cinnamaldehyde) with arenediazonium salts. From the synthetic viewpoint for tetrazoles, this method may be of high synthetic utility on account of the availability of starting materials, the simplicity of procedure, and higher yields.
Homolytic Aromatic Substitution by Iminyl Radicals. Photolysis of Aromatic Ketone O-Acyloximes in Aromatic Solvents
Authors: Sakuragi Hirochika , Ishikawa Shun-ichi , Nishimura Toshihiro , Yoshida Masayuki , Inamoto Naoki , Tokumaru Katsumi
Published: July 2006

Irradiation of benzophenone O-acetyloxime, O-phenylacetyloxime, O-benzoyloxime, and O-(p-chlorobenzoyl)oxime in benzene, toluene, chlorobenzene, or o-xylene effected aromatic substitution on the solvent molecules by diphenylmethaniminyl radicals to give N-diphenylmethylenearylamines only when benzoxyl or p-chlorobenzoxyl radicals were generated concurrently. A mechanism involving a participation of the sufficiently long-lived acyloxyl radicals is proposed for the iminylation reaction on the basis of the reactivity patterns in this substitution reaction. o-Phenylbenzophenone O-benzoyloxime was also photolyzed in benzene to give 9-phenylphenanthridine, the intramolecular cyclization product of 2-biphenylylphenylmethaniminyl radicals.
Conversion of Alkyl Chlorides to Bromides, Selective Reactions of Mixed Bromochloroalkanes, and Halogen Exchange
Authors: Willy W Edward , McKean Dennis R , Garcia Barbara A
Published: July 2006

Primary alkyl chlorides are quantitatively converted to their corresponding bromides in the presence of ethyl bromide, N-methyl-2-pyrrolidinone, and a catalytic amount of metal bromide. A variety of chlorides can be converted. Selective functionalization at bromine of several primary bromochloroalkanes was studied in conjunction with the chloride-bromide conversion for multistep syntheses. Methods for halogen exchange between chloride, bromide, and iodide in the octyl halide series are presented.
Ionic Adsorption of Lithium Bromide at the Mercury-Dimethyl Sulfoxide Interface
Authors: Yamamoto Kohichi , Hayano Shigeo
Published: July 2006

The specific adsorption of bromide ions on a mercury electrode from lithium bromide solutions of dimethyl sulfoxide (DMSO) has been studied through the measurement of the differential capacity and the interfacial tension. The capacity data showed the evidence that anions are more weakly, but cations are more strongly, solvated by DMSO molecules than by H2O. The amounts of specifically adsorbed bromide ions are greater than those values in water at the same electrode charge. The specific adsorption of cations (Li+) was not found in this study. The inner layer capacity due to the amounts of specific adsorbed anions was calculated, and the ratio of the distances from the metal to the inner Helmholtz plane and to the outer Helmholtz plane were deduced. These values are comparable to those for LiCl in DMSO, but are greater than for water.
On the Chemical Structure and Some Labile Hydrogens of 7-Methylguanosine
Authors: Nakanishi Mamoru , Tsuboi Masamichi , Nakagawa Iwao
Published: July 2006

Proton magnetic resonance and infrared absorption studies indicate that 7-methylguanosine has 1-NH, 2-NH2, and 8-CH groups in dimethylsulfoxide solution, while in an aqueous system of pH 6.0 these groups are subjected to rather rapid hydrogen exchange reactions with the solvent molecules, so that their life-times are respectively <<10−2  s, =0.025 s and =180 s at 25 °C.
Triplet Excitation Energy Transfer in the Vinyl Polymers with Pendant Carbazolyl Groups
Authors: Itaya Akira , Okamoto Ken-ichi , Kusabayashi Shigekazu
Published: July 2006

The triplet energy transfer in poly(N-vinylcarbazole)(PVCz) prepared by radical and cationic polymerization (PVCz(r) and PVCz(c) respectively), poly[2-(N-carbazolyl)ethyl vinyl ether](PCzEVE), and brominated PVCz (BPVCz) has been investigated by measuring the delayed emission spectra in solid films and rigid solutions at 77 K. The prompt and delayed fluorescence spectra both in the solid film and in the rigid solution at 77 K were different for PVCz(r) and PVCz(c). This seems to be due to the difference in tacticity between them. PCzEVE, in which the Cz groups are connected from afar to the skeletal chains by means of –O–CH2–CH2–bonds, showed the delayed fluorescence and the phosphorescence both in the rigid solutions and in the solid films at 77 K. The BPVCz film showed only the excimer phosphorescence. In the solid films of PVCz(r), PVCz(c), and PCzEVE, the Cz chromophore-delayed fluorescence increased with an increase in the concentration of triplet quenchers, such as naphthalene and fluorene. This phenomenon suggests the presence of a heterogeneous triplet-triplet annihilation in these aromatic vinyl polymer films. The quenching of the Cz chromophore phosphorescence both by the doping of the naphthalene in the solid films and by the doping of the 1,3-pentadiene in the rigid solutions obeyed the Stern-Volmer equation, and the migration coefficient, λ, and the mean exciton migration length, L, were obtained. The values of λ and L were in the following order; PVCz(r)>PVCz(c)>PCzEVE (>BPVCz) in the solid film and PVCz(r)>PVCz(c) in the rigid solutions. The order was explained by both the concentration of the intrinsic trap sites for triplet excitons and the distance between neighboring Cz chromophores in one polymer chain.
Heat Capacities and Some Vibrational Properties of Rubidium Chloride
Authors: Higashigaki Yoshiyuki , Chihara Hideaki
Published: July 2006

Molar heat capacities of RbCl were measured between 3 and 300 K with an adiabatic calorimeter and complete thermodynamic properties of the solids have been obtained. The nature of the lattice vibration spectrum of RbCl is examined in terms of the moments of spectrum. Values derived are θ0=184.9±1.3 K, θ∞=190.0±1.0 K, Ez(zero-point energy)=3.43±0.01 kJ mol−1. Those properties depend on the kind of cation rather than on the anion in alkali halides. Anharmonicity in the vibration is also discussed.
The Crystal Structure of (+)350-(R)-Propylenediamine-N,N′-dimethylethylenediamineplatinum(II) Di-μ-(+)-tartrato(4–)bis(antimonate(III)) Dihydrate
Authors: Matsumoto Keiji , Ooi Shun’ichiro , Sakuma Masao , Kuroya Hisao
Published: July 2006

The crystal of the title compound is monoclinic, with a=9.415(3), b=15.767(7), c=8.786(3) Å, β=94.25(4)°, the space group of P21 and Z=2. The structure was determined from the counter intensity data by heavy-atom techniques and was refined by the block-diagonal least-squares calculations to R 0.050 for 2604 non-zero reflections. The Pt atom has a square-planar coordination by 4N atoms, the secondary N atoms of which are of the S absolute configuration.
Equilibria and Substrate Specificity Studies with Alcohol Dehydrogenases
Authors: Price Charles C , Iwasa Mitsuhiro
Published: July 2006

While secondary alcohols and NAD+, and ketones and NADH react much slowly than the ethanol–acetaldehyde system in the presence of yeast and liver alcohol dehydrogenases, by starting near equilibrium concentrations, it has been shown that expected thermodynamic equilibria are obtained. With liver ADH, cycloalkanols are remarkably reactive, while with yeast ADH those with six or more carbon atoms in the ring are unreactive. Horse liver ADH shows stereospecificity for 2-octanol, but no stereospecificity for 2-butanol. On the other hand, yeast ADH shows the same stereoselectivity for both alcohols. In the presence of yeast ADH, R(−)-isomers of 2-butanol, 2-octanol and 1-methoxy-2-propanol are not reactive, comparing to the big reactivity of S(+)-isomers of these alcohols, but R(−)-isomer of propylene glycol is also slightly reactive as S(+)-isomer. Further, the reactivity of secondary alcohols with NAD+ in the presence of liver ADH is following, 2-octanol>2-butanol>2-propanol. These results suggest that horse liver ADH is much less sterically hindered at its active site than yeast ADH and that not only the steric factor but also hydrophobic bonding between the end alkyl group of alcohol and the hydrophobic region of enzyme might be another important factor to determine stereospecificity and reactivity of enzyme.
A Study of Metal–Ligand Vibrations in Nickelocene and Ferrocene
Authors: Yokoyama Kenji , Kobinata Shunsuke , Maeda Shiro
Published: July 2006

Raman and infrared spectra of nickelocene and ferrocene were studied as regards metal–ligand vibrations. It was found that the C5H5-ring tilt vibration, ν16(e1g), of nickelocene has considerably low frequency. This was discussed in view of metal–ligand binding between both metallocenes.
Studies of the Isomerization of Unsaturated Carboxylic Acids. II. The Thermal Rearrangement of Citraconic Acid to Itaconic Acid in Aqueous Solutions
Authors: Sakai Mutsuji
Published: July 2006

The thermal reaction of citraconic acid (2) in water gives a mixture of products similar to that obtained from itaconic acid (1) in water. After 22 h at 170 °C, the equilibrium composition about 74%, 18%, and 8% 1, 2, and mesaconic acid respectively. At the optimum conditions (170 °C for 3 h), the yield of 1 is 65%. The mechanism of the reaction is discussed.
Far Infrared Spectra of Solid 1,2-Dihalogenoethane
Authors: Hiraishi Jiro
Published: July 2006

Far infrared spectra are measured for solid 1,2-dichloro-, dibromo-, and diiodoethane at several temperatures. The translational lattice vibrations of the crystals are observed for both high and low temperature phases. The observed frequencies of the low temperature phase of 1,2-dichloroethane agreed with the frequencies calculated by Mizushima et al. (Ref. 5). The nature of the phase transition is discussed on the basis of the temperature dependence of the spectra. The low frequency Raman spectrum of 1,2-diiodoethane is also reported.
Reaction of 1-Alkylpyridinium Salts Carrying a Methyl or an Amino Group at the 2- or 4-Position with Activated Ethoxymethylene Compounds in the Presence of Alkali
Authors: Kakehi Akikazu , Ito Suketaka , Funahashi Takahisa , Ogasawara Norio
Published: July 2006

It was found that various 1-alkyl-2-(1a–d) and 4-picolinium salts(5a,b) react smoothly with ethoxymethylene compounds(2a–c) activated by electron-withdrawing substituents in the presence of alkali to give the corresponding 1-alkyl-2-(4a–i) and 4-allylidenedihydropyridine derivatives(6a–d) in fairly good yields. 1-Methyl-2-(vinylimino)dihydropyridine(8a) and pyrimidine(8b) were obtained by the reactions of 1-methyl-2-aminopyridinium(7a) and pyrimidinium iodide (7b) with ethyl ethoxymethylenecyanoacetate(2a) under similar reaction conditions.
The Reaction of 3,5-Dimethylisoxazole with Carbonyl Compounds
Authors: Kashima Choji , Uemori Masakazu , Tsuda Yoshihiko , Omote Yoshimori
Published: July 2006

The reaction product of 3,5-dimethylisoxazole (1) with methyl benzoate was found to be 3-methyl-5-(benzoylmethyl)isoxazole in the presence of sodium amide in liquid ammonia. On the other hand, the reaction of 1 with ethyl acetate did not give 3-methyl-5-acetonylisoxazole under similar conditions. The latter reaction product was, however, obtained in a good yield in the presence of lithium amide in liquid ammonia. The reaction of 1 with ketones and aldehydes was proved to give 3-methyl-5-(2-hydroxyalkyl)isoxazoles regiospecifically in the presence of alkali amide. In the above reactions, further alkylation gave 3-methyl-5-(2-alkoxyalkyl)isoxazoles in moderate yields. Compound 1 reacted with acrylaldehyde, crotonaldehyde, and cinnamaldehyde to give 1,2-addition products, 3-methyl-5-(2-hydroxyalkenyl)isoxazoles, exclusively, but methyl cinnamate and cinnamic acid gave only Michael addition products, 4-(3-methyl-5-isoxazolyl)butanoic acid derivatives.
The Polarized Crystal Spectra of trans(O)-[Co(OCOCH3)2(en)2]+ and trans(O)-[Co(OCOCH3)2(py)2en]+
Authors: Nagasaki Shunji , Shibata Muraji
Published: July 2006

The polarized crystal spectra of trans-(O)-[Co(OCOCH3)2(en)2]Cl have exhibited a dichroism which can be understood by means of a vibronic D4h model. On the other hand, the spectra of a new complex, trans(O)-[Co(OCOCH3)2(py)2en]ClO4, have shown a different dichroism from that in the bis(ethylenediamine) complex.
Electronic Configuration Analysis of Molecular Deformations
Authors: Okada Takashi , Nagase Shigeru , Yamaguchi Kizashi , Fueno Takayuki
Published: July 2006

A procedure is described which enables to trace the variations of electronic configuration of molecular systems undergoing structural deformation. The mapping operator proposed by Trindle is used to derive a reference set of molecular orbitals which is suitable to the analysis of the wave functions for deformed molecules. The method has been applied to the twisting of ethylene as well as the electrocyclic reactions of butadiene. The results corroborate Bader’s symmetry requirement for the electronic excitations accompanying nuclear displacements.
Studies on Pulse Polarography. IV. Normal Pulse Polarographic Behavior of Fe(II) in an Unbuffered Medium and Catalytic Wave for Fe(H)–Chlorate System
Authors: Himeno Sadayuki
Published: July 2006

The normal pulse polarogram of Fe(II) showed a double-wave behavior in an unbuffered solution containing iodate. The results of pulse polarographic and cyclic voltammetric studies indicate that colloidal Fe(OH)2 formed by the reaction between aqua-Fe(II) and OH− arising from the iodate reduction is responsible for the second wave. A catalytic wave was observed in the presence of chlorate in Tast polarography. The catalytic wave which appears to be a polarographic maximum, has an abnormal form, in which the current increases at every second or third drop because of the depletion of colloidal Fe(OH)2 around the electrode. The catalytic current is due to the reaction of chlorate with colloidal Fe(OH)2 formed in the vicinity of the electrode.
Reaction of a Stable Free Nitrogen-centered Radical, 3,4-Dihydro-2,4,6-triphenyl-2H-1,2,4,5-tetrazin-1-yl, with Grignard Reagents
Authors: Miura Yozo , Morimoto Yuzo , Kinoshita Masayoshi
Published: July 2006

The reactions of 3,4-dihydro-2,4,6-triphenyl-2H-1,2,4,5-tetrazin-1-yl (1) with Grignard reagents such as ethyl-, isopropyl-, butyl-, isobutyl-, s-butyl-, t-butyl-, cyclohexyl-, phenethyl-, phenyl-, and 2-naphthylmagnesium bromides and benzylmagnesium chloride were examined. In the reactions with the alkylmagnesium halides, coupling compounds (2) of 1 with alkyl radicals derived from the alkylmagnesium halides were isolated in 41–50% yields. On the other hand, in the reactions with arylmagnesium bromides the corresponding coupling compounds were not isolated, but biphenyl and 2,2′-binaphthyl were isolated in 87 and 86% yields, respectively. From these results, the reactions of 1 with Grignard reagents are concluded to proceed through a homolytic process.
β-Disulfoxides. II. The Preparation of Some Optically Active β-Disulfoxides
Authors: Kunieda Norio , Nokami Junzo , Kinoshita Masayoshi
Published: July 2006

α-Sulfinylcarbanions (1) derived from methyl-substituted sulfoxides readily react with arenesulfinic esters (2) to give the corresponding β-disulfoxides (3) in good yields. The reaction was conducted using (−)-menthyl (−)-(S)-benzenesulfinate ((−)-(S)-2b), (−)-menthyl (−)-(S)-p-toluenesulfinate ((−)-(S)-2c), and α-p-tolylsulfinylcarbanion derived from (+)-(R)- or (−)-(S)-methyl p-tolyl sulfoxide to produce (R,S)- and/or (S,S)-diastereoisomers of five β-disulfoxides (3a–e). The configurational assignment for the diastereoisomers obtained was accomplished by a combination of NMR and polarimetric analyses.