bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Oligomerization of Butadiene with Nickel Complexes Produced by Means of the Electrolysis of Nickel(II) Chloride
Authors: Ohta Takayuki , Ebina Keisuke , Yamazaki Noboru 
Published: July 2006

Abstract
The oligomerization of butadiene has been found during the electrolysis of solutions containing nickel(II) chloride and electron donors. The oligomerization was affected by the nature of the electron donors used. When the ethanolic solutions of tetrakis(pyridine)nickel(II) chloride or nickel(II) chloride and pyridine with tetra-n-butyl ammonium perchlorate or methanolic solutions without the perchlorate were electrolyzed in the presence of butadiene, a number of linear and dihydrogenated oligomers, with small amounts of branched oligomers, were obtained. The main oligomers were identified as n-octadiene, n-dodecatriene, and n-hexadecatetraene. By adding triphenylphosphine to the reaction system in place of pyridine, n-octatriene and alkoxyoctadiene were catalytically produced instead of hydrooligomers, accompanied by tetrakis(triphenylphosphine)nickel(0). A mechanism involving π-allyl intermediates was proposed for the oligomerization.
The Polymerizations of 2-Vinyl-4-acryloxy-1,3-dioxolane and 2-Vinyl-4-methacryloxy-1,3-dioxolane
Authors: Ouchi Tatsuro , Yokoi Kaneyuki , Yoshimura Kenzi , Oiwa Masayoshi 
Published: July 2006

Abstract
The polymerizations of 2-vinyl-4-acryloxy-1,3-dioxolane(VADO) and 2-vinyl-4-methacryloxy-1,3-dioxolane(VMDO), and the copolymerizations of those divinyl cyclic acetals with styrene (St) and acrylonitrile(AN), have been carried out at 60°C, using 2,2′-azobisisobutyronitrile as the initiator. They were discussed kinetically. The following results were obtained: 1) The polymerizations of the above cyclic acetals containing allylidene and vinyl groups proceeded primarily on the acryl or methacryl group, and the allylidene group was extinguished a little by means of cyclization; the ratios of the rate constant of the unimolecular cyclization reaction to that of the bimolecular propagation reaction of the uncyclized radical were 0.065 mol/l (VADO) and 0.114 mol/l(VMDO). 2) The following monomer reactivity ratios were obtained at 60°C: VADO(M1)-St(M2) r1=0.22, r2=0.81; VADO(M1-AN(M2) r1=0.89, r2=0.95; VMDO(M1)-St(M2) r1=0.51, r2=0.49. The Q and e values of the two monomers were calculated from these values: VADO, Q=0.41, and e=0.65; VMDO, Q=0.81 and e=0.38.
The Elimination Orientation in the Fluoride-promoted Olefin Formation. A Comparison with the Alkoxide-promoted Eliminations
Authors: Ono Noboru 
Published: July 2006

Abstract
When the 2-butyl and 2-pentyl derivatives were treated with tetraethylammonium fluoride in acetonitrile, an olefin-forming elimination took place and an overwhelming Saytzeff orientation was observed. The relative yield of 1-olefin was little affected by changes in the leaving group and β-alkyl group. These results were compared with the results of the eliminations with the conventional base-solvent systems (EtO− in EtOH, t-BuO− in t-BuOH, and t-BuO− in DMSO).
The Synthesis of Methylacetylene by the Pyrolysis of Propylene. VI. The Pyrolysis of Allyl Iodide
Authors: Kunichika Sango , Sakakibara Yasumasa , Taniuchi Mamoru 
Published: July 2006

Abstract
Allyl iodide has been pyrolyzed in a flow system over a wide range of conditions (temperature, 800–1100°C; contact time, 1.44×10−4–14.0×10−4 sec; concentration, 1.8–6.5 mol%; pressure, atmospheric pressure) in order to find suitable conditions for producing methylacetylene and allene and in order to elucidate the reactions of the allyl radical with iodine or the iodine atom at high temperatures. In addition, a study of the mechanism of the pyrolysis of allyl iodide at high temperatures (800–1100°C) has been made. A total yield of allene and methylacetylene of 10 mol per 100 mol of allyl iodide pyrolyzed was obtained under suitable conditions. In the pyrolysis, little cleavage of the C–C bonds of allyl iodide occurred, and propylene, allene, methylacetylene,diallyl, benzene, and an unidentified product were found to be the main products. By means of the zero-conversion method, diallyl alone has been found to be the major product in the early stage of the pyrolysis, while propylene, allene, methylacetylene, and benzene have been found to be the chief products at higher conversions. On the basis of the observed results, a free-radical mechanism has been proposed for the main reactions. It has further been concluded that the pyrolysis is a radical decomposition initiated by the C3H5I → C3H5·+I reaction and that the overall mechanism in the early stage of the pyrolysis may be represented essentially by the 2C3H5I → C6H10+I2 reaction.
Studies of the Thiocarbonyl Compounds. III. The Mechanism of the Thermal Rearrangement of Aryl Thionocarboxylates
Authors: Kaji Aritsune , Araki Yoshiaki , Miyazaki Koshin 
Published: July 2006

Abstract
The thermal rearrangement of aryl thionocarboxylates was kinetically investigated in diphenyl ether. The rate constants of the rearrangement of aryl N,N-dimethylthionocarbamates were well correlated with the σ− values, but the plots of the electron-releasing para-substituents deviated slightly on the lower side of the meta correlation line. A good linear free-energy relationship existed between the rearrangement of aryl N,N-dimethylthionocarbamates and the bimolecular nucleophilic reaction of 4- or 5-substituted 1-chloro-2-nitrobenzenes with piperidine. By the use of the substituent constants obtained from the latter reaction for the electron-releasing para-substituent constants, a fairly good ρ–σ− relationship was obtained. Linear free-energy relationships also existed between the rearrangements of aryl N,N-dimethylthionocarbamates and aryl thionobenzoates, and between the rearrangements of aryl N,N-dimethylthionocarbamates and O-aryl S-phenyl dithiocarbonates. The order of the reaction constants was in accord with that of the inductive effects of the α-substituents of the thiocarbonyl group, so the electron-releasing conjugative effects of the α-substituents of the thiocarbonyl group did not play important roles in the rate-determining step. The present results indicate that the thermal rearrangement of aryl thionocarboxylates is an intramolecular SN–Ar which involves a four-membered cyclic transition state formed by a nucleophilic attack of the lone-pair electrons of the thiocarbonyl sulfur atom on the migrating aromatic ring.
Studies of the Alkaline Earth Complexes in Various Solutions. VI. The Extraction and Complex Formation of Beryllium(II) in Sodium Perchlorate Media Containing Some Univalent Inorganic Anions
Authors: Serine Tatsuya , Komatsu Y\={u} , Sakairi Mitsuo 
Published: July 2006

Abstract
The distribution of beryllium(II) between methylisobutylketone containing TTA (thenoyltrifluoroacetone) and aqueous 4.0 m sodium perchlorate constant ionic media has been measured by using a carrier-free beryllium-7 tracer. The distribution behavior, determined as a function of the TTA and the hydrogen ion concentration, was explained in terms of the extraction of the Be(TTA)2, the Be(ClO4)2 and the mixed species Be(TTA)-(ClO4), and their extraction constants were determined. Then, the stability constants for the chloride, bromide, and nitrate complexes were determined from the decrease in the TTA extraction when some of the perchlorate ions in the aqueous phase were replaced by the ligand anions. Those of the thiocyanate complexes, on the other hand, were determined from the extraction of Be(SCN)2 species with TBP (tributylphosphate) in hexane. It was concluded that the stabilities of these complexes are very low; the values β1 and β2 range between 1 and 0.1, but still these complexes should be taken into account in any discussion of the chemical behavior under some experimental conditions.
Elimination Reactions Promoted by Fluoride Ion in Acetonitrile. Elimination Reaction from 2-Arylethyl Derivatives
Authors: Hayami Jun-ichi , Ono Noboru , Kaji Aritsune 
Published: July 2006

Abstract
Rates of bimolecular elimination have been determined for the reaction of 2-arylethyl bromides, chlorides, and tosylates with anhydrous tetraethylammonium fluoride in acetonitrile. The rates of elimination reactions in this new base system were much faster than those in conventional base systems (alkoxide-alcohol). The Hammett ρ values were found to be ρ=2.033 (X=Cl) at 25.0°C and ρ=1.879 (X=Br) at 5.0°C for p-Y-C6H4CH2CH2X. Kinetic deuterium isotope effects were determined using 2-phenylethyl-2,2-d2 bromide and chloride to be kH/kD=3.99 (X=Cl) and 5.03 (X=Br). These data and the low kOTs/kBr ratio suggest that fluoride-ionpromoted elimination reaction proceeds through a very tight transition state where β-proton is less than half transferred to the base.
The Hofmann Rearrangement. III. Kinetic Substituent Effects of 4- and 5-Substituted 2-Chloro-N-chlorobenzamides
Authors: Imamoto Tsuneo , Tsuno Yuho , Yukawa Yasuhide 
Published: July 2006

Abstract
The kinetic measurements of the Hofmann rearrangement of 2,4-, 2,5- 2,6-, and 3,5-disubstituted N-chlorobenzamides were carried out. The rate constants of 4- and 5-substituted 2-chloro-N-chlorobenzamides were applicable to the LArSR relationship:
logk⁄k0=−2.21(σ0+0.69Δ\barσR+)+0.003
indicating that the reactivity of the 2-chloro series was subjected to a larger additional conjugation effect than that of the 2-unsubstituted series. The detailed discussion of the reaction mechanism on the basis of these results supported strongly the concerted mechanism.
The Cyclization Products from Acetone with Cyanoacetic Esters
Authors: Igarashi Minoru , Midorikawa Hiroshi 
Published: July 2006

Abstract
The structure of the cyclization product from acetone with the cyanoacetic ester has been established as 3-alkoxycarbonyl(cyano)methylene-6-cyano-5,5-dimethyl-1-cyclohexene-1-ol by means of infrared and NMR spectroscopic determinations and by successive degradations.
Further Studies of the Chemical Cleavage of the Tryptophyl Bond by Ozonization-hydrazine Treatment
Authors: Sakiyama Fumio , Sakai Shin-ichiro 
Published: July 2006

Abstract
The second step (hydrazine treatment) in the chemical cleavage of the tryptophyl bond according to the scheme proposed previously was further studied under mild conditions using a model N′-formylkynurenyl peptide, carbobenzoxy-l-alanyl-N′-formyl-l-kynurenyl-l-leucine. The reaction of the model compound with an excess of hydrazine acetate at 25–30°C for 24–48 hr gave rise to the selective cleavage of the kynurenyl bond together with a concomitant tetrahydropyridazone formation. The maximum cleavage was 80–90%. It was then suggested that the incomplete cleavage of the tryptophyl bond in synthetic oligopeptides by means of ozonizationhydrazine treatment was mainly due to insufficient conversion of the indole nucleus into N′-formylanthranyl grouping in the first step (ozonization).
The Preparation of Deoxyguanosine Oligomers on an Insoluble Polymer Support
Authors: Shimidzu Takeo , Letsinger Robert L 
Published: July 2006

Abstract
The syntheses of deoxyguanosine-containing oligonucleotides, deoxyguanylyldeoxyguanylyldeoxyguanosine (d-GpGpG), deoxyguanylyldeoxyguanylyldeoxyguanylyldeoxyguanosine (d-GpGpGpG) and deoxyguanylyldeoxyguanylyldeoxyguanylylthymidine (d-GpGpGpT) have been described. Those nucleotidic materials were synthetized on an insoluble polymer support; the polymer was a copolymer of styrene, p-vinylbenzoic acid, and divinylbenzene. The blocking group used at the N-position of deoxyguanosine was di-p-methoxytrityl.
Nucleoside Analogs. II. A Synthesis of 9-Adenyl-deoxyinositols
Authors: Suami Tetsuo , Fukai Yasushi , Sakota Yukio , Karimoto Makoto , Takoi Nobuo , Tsukamoto Yoko 
Published: July 2006

Abstract
Four 9-adenyl-deoxyinositols were prepared by a reaction between 4-amino-6-chloro-5-nitropyrimidine (1) and inosamines (2a, 2b, 2c, and 2d), followed by a reduction and a cyclization. In the present article, 1-(6′-amino-9′-purinyl)-1-deoxy-scyllo-inositol (5a), 1-(6′-amino-9′-purinyl)-1-deoxy-muco-inositol (5b), 2-(6′-amino-9′-purinyl)-2-deoxy-epi-inositol (5c), and 2-(6′-amino-9′-purinyl)-2-deoxy-myo-inositol (5d) were described. These compunds exhibited an inhibitory effect against piricularia oryzae.
The Differential Thermal Analysis of Potassium Oxalate
Authors: Higashiyama Tatsuo , Hasegawa Shigeo 
Published: July 2006

Abstract
From the differential thermal and thermogravimetric analyses of potassium oxalate together with the X-ray diffraction studies, three crystallographic modifications of the anhydrous salt were found. When potassium oxalate monohydrate crystals were dehydrated at, e.g., 140°C, phase II, which is stable below 381°C, appears. The crystal in phase II has an orthorhombic unit cell (a=10.9, b=6.11, and c=3.44 Å at 17°C) and transforms at 381°C into phase I, which is stable above 381°C up to the temperature where the decomposition begins. The crystals in phase I belong to the tetragonal system (a=7.01 and c=7.53 Å at 404°C). The transition between phases II and I is not reversible in an exact sense, and when cooled phase I endures down to 215°C, where it transforms(reversibly) into phase III. Phase III can exist at room temperature. When heated, phase III transforms into phase I at 215°C (often accompanied by a partial transformation to phase II). The resulting phase then transforms into phase II. At all temperatures below 381°C phases I and III are metastable with respect to phase II, and they transform into phase II. The decomposition of potassium oxalate in an oxygen-free atmosphere seems to proceed in two stages.
Dehydration and Dehydrogenation of Alcohols over Acid-Base Bifunctional Catalysts
Authors: Niiyama Hiroo , Echigoya Etsuro 
Published: July 2006

Abstract
Alkaline earth silicates having both acidic and basic sites can be considered as acid-base bifunctional catalysts. Dehydration and dehydrogenation of alcohols over these catalysts were carried out. Correlation between the selectivity and acid-base properties of alcohols and the catalysts was studied. It was found that acid-base properties of both the catalysts and the alcohols were cooperative in determining the selectivity of reaction.
The Electron-acceptor Strengths of Some Substituted Naphthoquinones
Authors: Saito Gunzi , Matsunaga Yoshio 
Published: July 2006

Abstract
The electron-acceptor strengths of the substituted naphthoquinones were compared with that of p-chloranil in terms of their complexing properties. The following electron affinities were estimated: 2.05 eV for 2,3-dichloro-1,4-naphthoquinone, 2.24 eV for 2,3-dichloro-5-nitro-1,4-naphthoquinone, 2.74 eV for 2,3-dicyano-1,4-naphthoquinone, and 2.78 eV for 2,3-dicyano-5-nitro-1,4-naphthoquinone.
Solvolysis of Organic Phosphates. IV. 3-Pyridyl and 8-Quinoly Phosphates as Effected by the Presence of Metal Ions
Authors: Murakami Yukito , Sunamoto Junzo 
Published: July 2006

Abstract
Influence of nickel(II), copper(II), and thorium(IV) ions on the hydrolysis of 3-pyridyl and 8-quinolyl phosphates was investigated at μ=0.10 in a lower pH region. The reaction in the presence of the bivalent metal ions followed apparent first-order kinetics with respect to the phosphates in homogeneous phase. The copper ion showed a positive catalytic effect only on the hydrolysis of 8-quinolyl phosphate, and such effect increased markedly as pH was raised. The nickel ion, however, did not show any significant effect on the hydrolysis of both phosphates. The requisites for effective catalysis of bivalent metals have been postulated previously: (1) preliminary chelate formation, and (2) transitional chelate formation. Accordingly, complex formation of the present phosphates with copper(II) and nickel(II) was studied by means of potentiometric measurements. The results strongly suggest the importance of (1) for yielding catalytic efficiency. The presence of the thorium ion resulted in a profound acceleration of hydrolysis of both phosphates in a relatively lower temperature range. The reaction rate did not follow the simple kinetic law although the reaction system was kept homogeneous under the present experimental conditions. The complex formation with the phosphate moiety, which would provide effective charge neutralization for the substrate, is most likely the necessary cause for the thorium-catalysis. Plausible reaction mechanisms and the corresponding potential energy correlations were postulated for the present catalysis.
The Carbon-catalyzed Oxidation of Co(II)-Ethylenediaminetetraacetate by Molecular Oxygen
Authors: Tomita Akira 
Published: July 2006

Abstract
The kinetics of the oxidation of a cobaltous complex of ethylenediaminetetraacetic acid (EDTA) is determined volumetrically at 50.0°C in the presence of several kinds of carbon as catalysts. One mole of oxygen was used to oxidize four Co(II) ions, and all the Co(II) ions were oxidized to Co(EDTA)− ions quantitatively. The rate of oxygen uptake was found to change from zeroth order to first order with respect to the complex ion during the course of oxidation; it was also found to be first order with the oxygen pressure and the amount of the carbon catalyst. The catalytic activity of the carbon was correlated to the quantity of surface basic oxides of the carbon. A possible mechanism which can account for the above results is proposed.
Restricted Rotation Involving the Tetrahedral Carbon. I. Some Diels-Alder Adducts Derived from 9-Substituted Anthracenes
Authors: Oki Michinori , Suda Minoru 
Published: July 2006

Abstract
9-t-Butylanthracene was treated with dimethyl acetylenedicarboxylate and benzoquinone to give Diels-Alder adducts. The NMR spectra of these adducts suggest that the internal rotation about the C1–CBu bond is not taking place on the NMR time scale. On the other hand, a Diels-Alder adduct prepared from 9-isopropylanthracene and dimethyl acetylenedicarboxylate shows the coalescence phenomenon of the NMR signals when the temperature is raised. The possibility of optical resolution due to hindered rotation about the sp3–sp3 carbon bond is pointed out.
Reactions of Sulfonium and Pyridinium Salts with Alkyl Nitrite
Authors: Mukaiyama Teruaki , Saigo Kazuhiko , Takei Hisashi 
Published: July 2006

Abstract
It was found that α-bromo-α-hydroxyimino compounds were obtained in good yields by the reactions of sulfonium bromides, such as dimethylphenacylsulfonium bromide, acetonyldimethylsulfonium bromide and ethoxycarbonylmethyldimethylsulfonium bromide, with isopropyl nitrite. On the other hand, (α-hydroxyiminophenacyl and -acetonyl)pyridinium bromides were obtained in quantitative yields by the reactions of pyridinium bromides, such as phenacylpyridinium bromide and acetonylpyridinium bromide, with isopropyl nitrite. Further, the reactions of α-bromo-α-hydroxyimino compound or (α-hydroxyiminophenacyl)pyridinium bromide, which were obtained by the above mentioned reactions, with several nucleophiles were studied.
Kinetics and Equilibrium Positions of cis-trans Isomerization of 1,2-Bis(phenylthio)ethylene and Its Exchange with Benzenethiyl Radicals
Authors: Ohno Atsuyoshi , Saito Tomo’o , Kudo Akio , Tsuchihashi Gen-ichi 
Published: July 2006

Abstract
Kinetics of the cis-trans isomerization of 1,2-bis(phenylthio)ethylene induced by benzenethiyl radicals and the exchange of phenylthio group have been studied by using thiophenol-phenyl-14C Pseudo-first order rate constants for the isomerization and the exchange are 2.08±0.22×10−5 sec−1 and 2.03±0.26×10−5 sec−1 at 50°C, respectively. The cis/trans ratio of this olefin is 55–58/45–42 at the completion of the reaction, which differs from the value obtained from the reaction induced by iodine (48–49/51–52). The difference has been interpreted with the idea that the isomer composition in the cis-trans isomerization is determined by kinetic factors when the reaction is initiated by thiyl radicals.
The ESR Spectra of 2- and 6-Methoxyazulene Anion Radicals
Authors: Ikegami Yusaku , Seto Shuichi 
Published: July 2006

Abstract
The electron spin resonance spectra of 2- and 6-methoxyazulene anion radicals have been examined. The radicals were generated from neutral species either by electrolytic reduction in N,N-dimethylformamide or by the reduction with alkali metals in ethereal solvents. The experimental splitting constants are explained satisfactorily in terms of the calculated spin densities by McLachlan’s procedure.
A Theoretical Study of the Electronic Structures of Several Methyl Compounds of Group I, II, and III Elements
Authors: Ohkubo Katsutoshi , Shimada Hidetoshi , Okada Masahide 
Published: July 2006

Abstract
The electronic states of the group I, II, and III methyl compounds were investigated using the extended Hückel method, with particular reference to the nature of the bond of metal-carbon. First, the monomers of the group I methyl compounds indicated remarkable electron-localizations on the carbon atom in CH3. (CH3Li)4 was found to be a possible tetramer, its total energy being lower by 0.34 eV per CH3Li unit than that of the CH3Li-monomer in spite of the unstability of (CH3Li)2. Second, (CH3)4Be2 was more stable than (CH3)2Be by ca. 4.04 eV per (CH3)2Be unit. Third, the stability of (CH3)3B in the form of a monomer was understood well by the fact that its π-bond nature is so much in comparison with that of (CH3)3Al. Finally, the reactivities in a series of the groups were discussed briefly in connection with the electronic states.
Interaction between TCNQ and Surfactant. III. The Effect of Light on the Spectra of TCNQ Solubilized in Surfactant Solutions
Authors: Muto Shinya , Degughi Katsuhiko , Shimazaki Yoshikazu , Aono Yoshiaki , Meguro Kenjiro 
Published: July 2006

Abstract
The absorption spectra of 7,7,8,8-tetracyanoquinodimethane (TCNQ) solubilized in surfactant solutions were found to be influenced by day light (hereafter referred to as light). The formation of the monomer band of TCNQ, anion radical in the aqueous solution of DPCl (dodecylpyridinium chloride), DPBr (dodecylpyridinium bromide) and C12E8 (homogeneous octaethylene glycol dodecylether) were enhanced by light. On the other hand, the spectra of TCNQ solubilized in surfactant micelle in the dark suggested that TCNQ exists as dimer anion radical form (TCNQ)2\ewdot. Thus, in solubilized state of TCNQ in micelle there is an equilibrium between monomer TCNQ\ewdot and dimer (TCNQ)2\ewdot, which seems to be easily influenced by light and surfactant. Appearance of a monomer radical band was remarkable in DPCl, DPBr, and C12E8 but only the dimer band was found in SDS even in the light.
The Coadsorption of Nitric Oxide, Nitrogen, and Oxygen on Rhenium
Authors: Tamura Teijiro 
Published: July 2006

Abstract
The coadsorption of nitric oxide, nitrogen, and oxygen on a polycrystalline rhenium filament was studied using flash desorption mass-spectroscopy. Substitutional desorption was not observed during the adsorption of nitric oxide, nitrogen, or oxygen on preadsorbed leayers. No oxygen or nitrogen adsorbs on rhenium saturated with nitric oxide. However, nitric oxide adsorbs on rhenium saturated with nitrogen or oxygen. The strength of the chemisorption bond between rhenium and adsorbed species becomes weaker in the order of: nitric oxide, oxygen, and nitrogen. When the same amount of nitric oxide molecules exist in various coadsorbed layers, the Tp of the nitrogen desorption spectrum from these layers is shifted to a lower temperature with an increase in the number of oxygen atoms in them, because the strength of the chemisorption bond of Re–N is weakened by the strongly-bonded Re–O. No desorption of the nitric oxide molecule from a coadsorbed layer of the “N2+O2” on rhenium was observed.