bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of Ruthenium Complexes. IV. The Solvent Effect on the Isotopic Ligand-exchange Reaction of the cis- Dibromotetraammineruthenium(III) Complex
Authors: Ohyoshi Akira , Shinohara Tetsuo , Hosoyamada Yoshihiro , Yamada Takato , Hiroshima Yutaka 
Published: July 2006

Abstract
The isotopic ligand-exchange reactions of cis-dibromotetraammineruthenium(III) were studied in aqueous and methanol-water solutions in order to distinguish them from those in the case of the monobromocomplex and in order to ascertain the role of the water molecule with respect to the reaction mechanism. In an aqueous solution, the reaction proceeds through the rate-determining aquation step with the SN2 mechanism: Ru(NH3)4Br2++H2O→Ru(NH3)4(H2O)Br2++Br−, Ru(NH3)4(H2O)Br2++*Br−→Ru(NH3)4Br*Br++H2O. This result is similar to that for the monobromocomplex. In the methanol solution (H2O∼1.5%), the exchange reaction proceeds through the SN1 mechanism: Ru(NH3)4Br2+→Ru(NH3)4Br2++Br−, Ru(NH3)4Br2++*Br−→Ru(NH3)4Br*Br+. When the concentration of water becomes very low, the number of solvated water molecules decreases; therefore, the coordinated bromide ion may easily be liberated. When the concentration of water is higher than 10%, the rate constant increases with the increase in the water concentration. Since the electronic spectra did not change during the exchange reaction, it would seem that the water molecule attacks a cis-position as a nucleophile. These results can be interpreted by postulating a hydrogen-bond between the proton of the water molecule and the coordinated bromide ion.
The Synthesis of Some N,N-Dialkylselenocarbamate Complexes of Tin(IV), and Their Infrared and PMR Spectra
Authors: Tanaka Koji , Araki Shigeo , Tanaka Toshio 
Published: July 2006

Abstract
Several N,N-dialkylselenocarbamate complexes of tin(IV), (CH3)2Sn[OSeCNR2]2 (1), (CH3)2ClSn[OSeCNR2] (2) (R=CH3 and C2H5) and (CH3)3Sn[OSeCN(CH3)2] (3), have been prepared, and their infrared and proton magnetic resonance spectra have been examined. The results indicate that in 1 and 2 the selenocarbamate ligands are coordinated to the tin atom in a bidentate manner, although the coordination of the oxygen atom is weak. On the other hand, 3 has a tetra-coordinate tin with a free carbonyl bond. The configurations of these complexes are discussed and compared with those of the corresponding thio-, dithio-, diseleno-, and thioselenocarbamate complexes of tin(IV).
Add nets of Neodymium(III) and Lanthanum(III) Acetylacetonate with some Bidentate Organic Bases
Authors: Yoshida Isao , Kobayashi Hiroshi , Ueno Keihei 
Published: July 2006

Abstract
Several bidentate uncharged organic base adducts of neodymium(III) and lanthanum(III) acetylacetonate were prepared by the reaction of the free bases with tris(acetylacetonato)neodymium(III) monohydrate and tris-(acetylacetonato) lanthanum(III) dihydrate in ethyl acetate, respectively. Elemental analyses, molecular weight determinations, NMR, IR, and visible absorption spectra indicate that the adducts are of the general formula Ln(AA)3(BB), where AA, BB, and Ln denote acetylacetonate ion, bidentate uncharged base and lanthanide ion, respectively. Thermal stability of the base adducts as well as the hydrates was studied by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). Coordination of the additional ligand having reactive hydrogen atoms resulted in poor thermal stability of the addition complexes. This might be explained by assuming that the coordinated acetylacetonate ion reacts readily with the reactive hydrogen atom of the neighboring ligand to liberate acetylacetone molecule, though the nature of the resulting pyrolyzed products is unknown.
Hexaammine, Tris(ethylenediamine), Glycinato, and l-Alaninato Complexes of a Triperiodatotetracobaltate(III) Condensed Anion
Authors: Ama Tomoharu , Hidaka Jinsai , Shimura Yoichi 
Published: July 2006

Abstract
Malaprade’s triperiodatotetracobaltate(III) heteropoly condensed acid, H3[Co4I3O18(OH2)6]·nH2O, was characterized by examination of its coordination derivatives with ammonia, ethylenediamine, glycinato, or l-alaninato ligands. It was concluded that the ion of parent acid and its derivatives, [Co4I3O18X6]n− (X6=(OH2)6, (NH3)6, en3, (OH2)4(gly), or (OH2)4(l-ala)), commonly have a hexol-like arrangement of four cobalt(III) octahedra so that the whole skeletons are based on the Anderson structure. The hexol-like configuration is chiral, this being demonstrated by the separation of two diastereomers of [Co4I3O18(OH2)4(l-ala)]4− ion.
Selective Formations of Several Carboxylic Acids by Carbonylation in the SbCl5–Liquid Sulfur Dioxide System
Authors: Yoshimura Masakatsu , Nojima Masatomo , Tokura Niichiro 
Published: July 2006

Abstract
The carbonylations of cis- and trans-4-t-butyl-1-methylcyclohexanols, exo- and endo-2-methyl-2-norbornanols and exo- and endo-2-norbornanols were carried out in SbCl5–liq.SO2 at −70°. From both the cis- and trans-4-t-butyl-1-methyl-cyclohexanols, cis-4-t-butyl-1-methylcyclohexanecarboxylic acid was formed exclusively in an excellent yield (over 90%). Both exo- and endo-2-methyl-2-norbornanols gave only endo-2-methyl-exo-2-norbornylcarboxylic acid in a high yield. The reason for the stereoselectivity of the reactions was discussed.
Peptides. IV. Racemization Suppression by the Use of Ethyl 2-Hydroximino-2-cyanoacetate and Its Amide
Authors: Itoh Masumi 
Published: July 2006

Abstract
Racemization suppression by the addition of ethyl 2-hydroximino-2-cyanoacetate (IIIa) or 2-hydroximino-2-cyanoacetamide (IIIb), during coupling stages in peptide synthesis, was studied. The effectiveness of IIIa was compared with these of known additives by the help of Bodanszky’s test, which is a simple and accurate method for racemization detection.
Microwave Spectrum of Arsenic Trifluoride in the Excited Vibrational State
Authors: Chikaraishi Toshio , Hirota Eizi 
Published: July 2006

Abstract
The microwave spectrum of arsenic trifluoride was observed in the excited states of all the normal vibrations. The rotational constant at the equilibrium state was determined, and the equilibrium As–F distance was calculated to be 1.7044 Å assuming the FAsF angle to be 95°58′. The l-type doubling constant, q4, and the asymmetry parameter, η, of the As nuclear quadrupole coupling constant were determined in the v4=1 to be 10.24±0.02 MHz and −0.005±0.01, respectively.
The pH-dependent Variation of the Absorption and Circular Dichroism Spectra in Some Ternary Mixed Complexes of Copper(II) Containing Diethylenetriamine and Optically Active Amino Acids
Authors: Murakami Tasuku , Nozawa Tsunenori , Hatano Masahiro 
Published: July 2006

Abstract
The absorption and circular dichroism(CD) spectra of some ternary mixed complexes of copper(II) with diethylenetriamine(dien) and various optically active α-amino acids have been measured in an aqueous solution at various pH values. The amino acid may coordinate to one of the planar positions, with its carboxylate or amino group as a unidentate ligand, in a neutral or a very high pH region. On the other hand, from the red shift of the d–d absorption band and the augmentation of the visible CD magnitude, it seems reasonable to expect that a large portion of the amino acid will form a chelate ring with an axial ligation in the pertinent pH region.
Palladium-Catalyzed Coupling Reaction of Aromatic Compounds
Authors: Yoshimoto Hataaki , Itatani Hiroshi 
Published: July 2006

Abstract
The oxidative coupling reaction of aromatic compounds proceeds catalytically with palladium salt under oxygen pressure. Yields and isomer distributions are attributed to the reaction variables such as temperature, additives, and the nature of the substituent on a benzene ring. Naphthalene was converted mainly into 1-substituted products and o-xylene into 4-substituted products. The coupling of diphenyl ether afforded diphenylene oxide with coupling dimers. An intramolecular two stage dehydrogenation process is proposed.
Studies on Carbamoylation Reactions of Polyethylenimine and Its Low Molecular Weight Analogues with Cyanate Ions
Authors: Okubo Tsuneo , Ise Norio 
Published: July 2006

Abstract
Garbamoylation reaction of ions of polyethylenimine and its low molecular weight analogues, i.e., ethyl-enediamine, triethylenetetramine, and tetraethylenepentamine, with cyanate ions are investigated in the presence of simple-, micelle-, and poly-electrolytes and in their absence. The rate constants are practically independent of the valency of the cations and are much larger than that previously found for the ammonium cyanate reaction. Both of the activation enthalpy and entropy decrease with increasing valency of the cations. Added electrolytes are found to decelerate the reactions. The reactions of poly cations are retarded more strongly by simple cations than by catalyst polycations, whereas those of simple cations are decelerated more effectively by polycations than by simple cations. The kinetic data are discussed thermodynamically in terms of the Bronsted theory and the activity coefficients of the reactant ions. The interaction parameters between reactant electrolyte and added electrolyte are also derived thermodynamically and discussed.
A Theoretical Consideration of the Electron-scavenging Process in Liquid Hydrocarbons. IV. Integral Transforms in the Prescribed Diffusion Approximation
Authors: Yamazaki Hideo , Shinsaka Kyoji 
Published: July 2006

Abstract
The relations of the integral transforms and the integral form between various distribution functions have been discussed in the prescribed diffusion approximation for the Smoluchowski equation. The initial electron distribution from the central-ion cluster in a spur or a track, ω(r, 0); the time dependence of the central value of the electron distribution, ω(0, t); the time dependence of the space-averaged electron concentration, N(t), after pulse irradiation, and the scavenger-concentration dependence of the relative G-value of electron scavenging, Gs(ksCs), as a function of the scavenger concentration, Cs, and the rate constant, ks, are shown to be connected by this diagram of the Laplace transforms and the integral form:
(Remark: Graphics omitted.)
By the use of this relation, the various distribution functions are evaluated from the generalized Gaussian initial distribution. The square-root relationship of the Gs(ksCs) to the scavenger concentration is discussed.
The Magnetic Properties of Manganese(II) Phthalocyanine
Authors: Miyoshi Hirokazu , Ohya-Nishiguchi Hiroaki , Deguchi Yasuo 
Published: July 2006

Abstract
The magnetic transition from the ferro- to the para-magnetic state of manganese(II) phthalocyanine (C32H16N8Mn) has been observed by measurements of the magnetic susceptibility, the magnetization and the proton magnetic resonance in the low-temperature range. The positive Weiss constants were obtained from the static susceptibility measurements and the proton magnetic measurements. Moreover, the magnetic-field dependences of the experimental results were found in the low-temperature range. All of those findings confirm the ferromagnetic behavior of this substance in the lower-temperature region. From the measurements of the frequency shift in the resonant circuit of the proton magnetic resonance apparatus, the transition temperature was determined to be 8.6 K. A possible mechanism of long-range ordering was also discussed on the basis of the crystal structure of this substance.
Ion-selective Electrodes Sensitive to Some Organic Compounds Used as Drugs
Authors: Kina Kenyu , Maekawa Nobuko , Ishibashi Nobuhiko 
Published: July 2006

Abstract
Drug ion-selective electrodes with a liquid membrane have been developed which are sensitive to methacholine, neostigmine, N-1-methyl nicotinamide, diphenhydramine, vitamin B1, vitamin B6, p-aminosalicylic acid (PAS), and salicylic acid. Crystal violet or ferroin-compound cations and dipicrylamine or tetraphenylborate anions were used as the ion-exchange sites in the liquid membrane. Each liquid membrane was prepared by using the solvent-extraction method and exhibited an appropriate Nernstian response to the respective ion down to 10−4 or to 10−5 M. The electrode performances, including the selectivity coefficients, are summarized in Table 1.
Catalytic Function of Metal Chelates in the Hydration of 2-Pyridinecarbonitrile
Authors: Watanabe Ken-ichi , Komiya Shigeo , Suzuki Shinnichiro 
Published: July 2006

Abstract
The catalytic effects of various transition metal complexes on the hydration of 2-pyridinecarbonitrile have been investigated. In these homogeneous catalytic reactions, free 2-pyridinecarboxamide was obtained as the sole reaction product. The transition metal species of the complexes used were Cu(II), Ni(II), Co(II), Co(III), and Pt(IV), while the ligands were ethylenediamine, bipyridine, glycine ion, and 2-pyridinecarboxamide. The complexes of Cu(II), Ni(II), and Co(II) were all catalytically active for the hydration, but those of Co(III) and Pt(IV) were inactive. No reaction occurred with 3- and 4-pyridinecarbonitriles under the same reaction conditions. The effect of the pH was remarkable. The active complex catalysts were classified into three types.
The Reaction of Nitriles under High Pressure. III. The Cyclotrimerization of Aliphatic Nitriles in the Presence of Alcohols and the Rearrangement of the Resulting Trialkyl-1,3,5-triazines to 4-Aminopyrimidines
Authors: Yanagiya Koshin , Yasumoto Masahiko , Kurabayashi Masahiro 
Published: July 2006

Abstract
The examination of the simultaneous formation of symmetrically tri-substituted 1,3,5-triazines, 4-amino-2,5,6-substituted pyrimidines and N-pyrimidylamidines in mixtures of lower alcohol and nitrile with more than two hydrogen atoms on the α-position under pressures of a few thousand atm afforded the following information: (1) the triazine is formed by the cyclo-trimerization of the iminoether which is derived from the nitrile and the alcohol; (2) the pyrimidine is formed by the rearrangement of the previously-formed triazine. This rearrangement is caused by an attack of the nucleophilic iminoether on a carbon atom of the triazine ring; and (3) the amidine is assumed to be formed, together with the pyrimidine, by the same attacking mechanism.
Kinetic and NMR Spectroscopic Studies of the Fusion Reactions of Chloropurines with 1,2,3,5-Tetra-O-acetyl-d-ribofuranoses
Authors: Hosono Akira , Fujii Kiyohisa , Tada Toshizo , Tanaka Hisayuki , Ohgo Yohko , Ishido Yoshiharu , Sato Tetsuo 
Published: July 2006

Abstract
A kinetic study of the fusion reaction and the reaction in dimethyl sulfoxide of 2,6-dichloropurine with 1,2,3,5-tetra-O-acetyl-β-d-ribofuranose was undertaken, and both of them were proved to be of the second order. The activation energy and the activation entropy of the reaction in dimethyl sulfoxide were obtained: Ea=38.0 kcal/ mol and ΔS\eweq=+15.3 cal · mol. The reaction was thus concluded to be bimolecular involving a considerable unimolecular character. Subsequently, the fusion reactions of 2,6-dichloro- and 2,6,8-trichloropurine with 1,2,3,5-tetra-O-acetyl-α- and -β -d-ribofuranose were examined by NMR spectroscopy with respect to the relative content ratios of all the materials and products in each reaction mixture; the results were found to be in good agreement with those obtained by the above kinetic study. On the basis of these results, the mechanism of the fusion reaction was discussed.
Oxidative Additions of Alkyl Halides to Palladium(0) Carbonyl Complex
Authors: Kudo Koji , Sato Michito , Hidai Masanobu , Uchida Yasuzo 
Published: July 2006

Abstract
Oxidative addition reactions of alkyl halides to Pd(CO)(PPh3)3 were studied. Vinyl chloride, allyl chloride, allyl bromide, methallyl chloride, benzyl bromide, methyl iodide, and iodobenzene react with Pd(CO)(PPh3)3 to afford the corresponding acyl complexes of the type to the type trans-PdX(COR)(PPh3)2. The reactions proceed rapidly when the dissociation energy of carbon-halogen bond in the saturated alkyl halides is smaller than about 60 kcal/mol. In the case of the unsaturated alkyl halides the more inert carbon-halogen bond can be activated by initial formation of π complexes.
Crystal and Molecular Structure of ω-Amino Acids, ω-Aminosulfonic Acids and Their Derivatives. VI. The Crystal and Molecular Structure of Dl-γ-Amino-β-hydroxybiityric Acid (GABOB), A Nervous Inhibitory Chemical Transmitter
Authors: Tomita Ken-ichi , Harada Masahiro , Fujiwara Takaji 
Published: July 2006

Abstract
Dl-γ-Amino-β-hydroxybutyric acid (GABOB), C4H9O3N, forms monoclinic plate crystals of space group P21/c, with a=7.43, b=8.29, c=9.34 Å, β=110.9°, and four molecules in the unit cell. Intensity data were collected by a film method. The structure was solved by the direct method with the symbolic addition procedure, and refined by least-squares methods to R=0.096. GABOB molecule having the zwitterionic structure, NH3+–CH2–CH(OH)–CH2–COO^-, forms trans-zigzag skeletal conformation with an intramolecular OH···O hydrogen bond of 2.773 Å, and contacts with each other by three dimensional network of NH···O and OH···O hydrogen bonds.
Polarographic Studies of the Associated Ion-pairs of Polyphosphate with the Hexaamminecobalt(III) Ion
Authors: Matsuura Niro , Umemoto Kisaburo , Takizawa Masao , Sasaki Yukio 
Published: July 2006

Abstract
The polarographic behavior of the hexaamminecobalt(III) ion was studied in solutions of polyphosphate with different numbers of chains. The decrease in the diffusion current, id with an increase in the phosphate (Cp)-to-hexaamminecobalt(III) (CCo) mole ratio was found to be proportional to 1/4 the power of the molecular weight, M, of the Co(NH3)63+-polyphosphate. This fact shows the associated ions between Co(NH3)63+ ions and polyphosphate anions are transported to the electrode by diffusion at a rate depending on the square root of the molecular weight of the diffusion depolarizer. From the shift of the half-wave potential in the presence of excess polyphosphate, the chemical compositions of the associated ion-pairs were determined as a function of log Cp/CCo.
Classification of Polarographic Current-Potential Curves of Inorganic Anions as a Function of Reduction Potentials
Authors: Umezawa Yoshio , Hirota Michio , Fujiwara Shizuo 
Published: July 2006

Abstract
DC polarographic behaviors of a variety of inorganic anions are examined systematically. Irrespective of chemical species, the shapes of current-potential curves are classified into three groups as a function of reduction potentials: i) E1⁄2&gt;0 V(SCE); The so-called minima cannot be observed beyond the ecm potentials, ii) 0 V&gt;E1⁄2&gt;ecm; The minima can be observed, iii) E1⁄2&lt;ecm; The distortion at the rising portion of the DC polarograms can always be observed. These results suggest that whether the minima can be observed or not is due to the difference in the relative position of half-wave potentials with respect to the ecm potential. Furthermore, it is likely that the distortion at the rising portion of the DC polarogram of Group iii) is similar in origin to that of the minima of Group ii). The present results are discussed in terms of the electron density and electronic energy level of electrons in the metal electrode. The discussion based on the phenomenological equation of Butler was also given for the sake of comparison to explain the observed phenomena.
Superacids and Their Derivatives. III. Kinetics of the Oxonium Ion Formation from Superacid Esters and Tetrahydropyran. Oxonium-Ester Equilibria
Authors: Kobayashi Shiro , Ashida Tadashi , Saegusa Takeo 
Published: July 2006

Abstract
Kinetic studies on the oxonium formation reaction between superacid esters (ROSO2X) and tetrahydropyran (THP) were carried out by means of NMR spectroscopy. The reaction was found to be an equilibrium process.
(Remark: Graphics omitted.)
The rate constant (k) of Sn2 reaction and the equilibrium constant (1⁄K=k⁄k′) were determined. The solvent effect was examined and k was found to be in the order: nitrobenzene&gt;chlorobenzene≈CH2Cl2&gt;liquid SO2. The effects of R and X in ROSO2X were studied. Relative reactivities of primary alkyl series in the reaction of ROSO2C1 with THP were: Me: Et: n-Pr=4.63: 1.0: 0.294 in CH2Cl2 and Me: Et: n-Pr=3.19: 1.0: 0.452 in nitrobenzene. The effect of X on k was in the order Cl≈CF3&gt;F, the 1⁄K value being also extremely low when X=F. The result was discussed in relation to the kinetics of the polymerization of tetrahydrofuran (THF) by ROSO2X.
Photochemistry of Heterocyclic Compounds. VI. The Photochemical Behavior of Phenazine in Hydroxylic Solvents
Authors: Wake Shigeo , Otsuji Yoshio , Imoto Eiji 
Published: July 2006

Abstract
The photochemical behavior of phenazine in acidified hydroxylic solvents varied with the concentration of acids present in the solutions. Irradiation of phenazine in an aqueous phosphoric acid afforded a 1 : 1 mixture of phenazinium and 1-hydroxyphenazinium cation radicals which were converted to a mixture of phenazine and 1-hydroxyphenazine. Irradiation in moderately strongly acidified alcohols (0.1–1.0 M HCl in alcohols) or in acetic acid containing 0.1 M p-toluenesulfonic acid yielded a 1 : 1 mixture of phenazine and the corresponding 1-alkoxyphenazines or 1-acetoxyphenazine after work-up of the reaction mixture. On the other hand, irradiation in a very strongly acidified methanol (5.6–9.6 M HCl in methanol) gave only the phenazinium cation radical. Mechanistic studies revealed that in the moderately strongly acidified media the reaction proceeds through a solvent-addition to the excited singlet phenazinium monocation, and in the very strongly acidified methanol the reaction proceeds through an electron transfer from the solvent to the excited singlet phenazinium dication.
The Structure and Reactivity of Organic Ions in Gas-phase Radiolysis. VIII. The C7H7+ Ion from Toluene and Ethylbenzene
Authors: Sagi Nobuo , Yamamoto Yukio , Nagaoka Kenji , Takamuku Setsuo , Sakurai Hiroshi 
Published: July 2006

Abstract
The gas-phase radiolysis of a mixture of toluene or ethylbenzene and dimethylamine has been studied at room temperature as a function of the dimethylamine pressure in order to investigate the structure and reactivity of the C7H7+ ion. The structure of the C7H7+ ion which takes part in the subsequent ion-molecule reaction was suggested to be the benzyl type on the basis of the reaction products. The radiolyses of toluene-α-d3 and ethylbenzene-α-d2 in the presence and in the absence of dimethylamine have been investigated, and the following information has been obtained: (i) the C7H7+ ion formed from toluene and ethylbenzene mainly consists of the benzyl ion, retaining its original structure; (ii) two types of scrambling processes may be involved in the C7H7+ ion formation, one of which, especially important in the case of toluene, includes the ring expansion of the original molecular ion, while the other consists of repeated rapid isomerization between the benzyl ion and the tropylium ion. These results were compared with those of mass spectrometric studies, which indicate that an almost complete isotope scrambling occurs, hence supporting the symmetrical tropylium structure for the C7H7+ ion.
UV-Spectra of Fluorenyl Salts in the Binary Mixtures of DME and Benzene
Authors: Takaya Katsuhiko , Ise Norio 
Published: July 2006

Abstract
The temperature dependence of UV spectra of fluorenyl lithium and sodium was investigated in 30, 40, and 50 vol% dimethoxyethane (DME)–benzene mixtures. The lithium salt had two absorption peaks at 352 and 373 nm, and the sodium salt at 358 and 373 nm. The fraction of solvent-separated ion pairs for the sodium salt was much lower than that of the lithium salt, and the heat of conversion (−ΔHi) of contact-ion pairs to solventseparated ion pairs was larger (9–11 kcal/mol) for the sodium salt than that (1–4 kcal/mol) for the lithium salt.