bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactions of Methylcalcium Iodide. II. Carboxylation, Metalation, and Metal-Halogen Exchange Reactions
Authors: Kawabata Nariyoshi , Yoshimura Hirotsugu , Yamashita Shinzo 
Published: July 2006

Abstract
Utility of methylcalcium iodide in several organic reactions in tetrahydrofuran was shown. Carboxylation of methylcalcium iodide at −70 °C gave acetic acid in 57–63% yield. Metallation of indene and fluorene by methylcalcium iodide at −30 °C gave 3-indenyl- and 9-fluorenylcalcium iodides in 99 and 93% yields, respectively. Metal-halogen exchange reactions of methylcalcium iodide with halobenzenes were rather slow.
Kinetic Studies on the Selenization of Silver
Authors: Mizusaki Jun-ichiro , Fueki Kazuo , Mukaibo Takashi 
Published: July 2006

Abstract
In order to elucidate the kinetics of selenization of silver by liquid selenium, the Ag/Ag2Se interface reaction rate, the ionic conductivity of Ag+ in Ag2Se layer, the Ag2Se/Se(1) interface reaction rate, and the over-all reaction rate were determined. The Ag/Ag2Se interface reaction rate was found to be given by
υ=1.6×10^9{exp(-32300/RT)}(a_Se) eqv cm^-2·s^-1
The following mechanism was proposed for the interface reaction.
2Ag(Ag)+Se(Ag_2Se)→2Ag^+(Ag_2Se)+Se^2-(Ag_2Se)
It was found that the driving force of the Ag2Se/Se(1) interface reaction is very small and Ag2Se is in equilibrium with Se(1). On an assumption that the over-all reaction is controlled by both the Ag/Ag2Se interface reaction and the diffusion of Ag+ in Ag2Se, the over-all reaction rates were calculated. The results agree with the observed ones.
MCNDO/2 Calculation of the Radiative Lifetimes of the Triplet States of the Nucleic Acid Bases
Authors: Kamiya Mamoru , Akahori Yukio 
Published: July 2006

Abstract
The radiative lifetimes of the lowest excited triplet states of the nucleic acid bases were calculated using a first-order perturbation treatment of the spin-orbit coupling. The calculated lifetimes were in the sequence of pyrimidines&gt;purines; that of thymine was found to be largest. The relation between the radiative lifetimes and biological photo-deactivation was discussed.
The ESR of Alkyl Phenyl Nitroxide Radicals Studied as Hindered Rotation
Authors: Nishikawa Toshio , Someno Kazuo 
Published: July 2006

Abstract
The ESR spectra were obtained in the series of N-methyl, N-ethyl, N-n-propyl, N-isopropyl, N-n-butyl, and N-tert-butyl phenyl nitroxide radicals. Two tendencies were found in the hyperfine splitting constants and were explained as hindered rotation.
The Spectrophotometric Determination of Boron in Condensed Water from Fumaroles
Authors: Isozaki Akinori , Utsumi Satori 
Published: July 2006

Abstract
A simple and accurate spectrophotometric method for determining boron in condensed water from fumaroles has been developed. The proposed method is based on the methylene blue-tetrafluoroborate ion pair. It was possible to determine micro amounts of boron with satisfactory results without any interference of foreign ions.
The Alkylation of m-Cresol with Propylene by Supported Metal Sulfates
Authors: Nitta Masahiro , Yamaguchi Katsumi , Aomura Kazuo 
Published: July 2006

Abstract
The alkylation of m-cresol with propylene over supported metal sulfate catalysts was studied at 250 °C under atmospheric pressure. The activity of the catalyst varied with the kind of sulfate and the calcination temperature, whereas the selectivity to thymol was independent of those factors and depended on the type of carrier instead.
Pyrolysis of Dialkyl 2-Acyloxyalkylphosphonates
Authors: Okamoto Yoshiki , Kawai Toshikazu , Sakurai Hiroshi 
Published: July 2006

Abstract
The pyrolysis of dialkyl 2-acyloxyalkylphosphonates at 220–240 °C gave the corresponding alkyl carboxylates and olefins by the elimination of metaphosphoric acid (HPO3)n.
Metal Phosphinylides and Phosphinothioylides. III. Reactions of Lithium Diphenylphosphinylide and Diphenylphosphinothioylide with Acetone and Bromoacetone
Authors: Yoshifuji Masaaki , Gomi Hideyuki , Inamoto Naoki 
Published: July 2006

Abstract
Reaction of acetone with [Ph2PO]Li gave 1-hydroxy-1-methylethyl- (2a), 1,1-dimethyl-3-oxobutyldiphenylphosphine oxides (3a) and 2,6-bis(diphenylphosphinyl)-2,6-dimethylheptan-4-one (4a). The corresponding sulfide 2b was obtained in the case of Ph2P(S)H, and 3b and 4b in the case of [Ph2PS]Li (5b). Bromoacetone reacted with 5b through substitution reaction.
The Reaction of Several o-Methoxy Aromatic Aldehydes with Ethylthioxide. Novel Substitution and Condensation
Authors: Iwata Masaaki , Emoto Sakae 
Published: July 2006

Abstract
The reaction of o- and p-anisaldehyde with potassium ethylthioxide in diglyme at 90–120 °C gave the corresponding demethylated products, while 2,6-dimethoxy-benzaldehyde and 9-(2-p-cymenyl)-2-methoxy-1-anthralde-hyde afforded two novel condensation and substitution products, VII and VI respectively.
The Application of an MC-SCF Theory to Organic Chemical Reactions
Authors: Kikuchi Osamu , Aoki Katsutoshi 
Published: July 2006

Abstract
MC-SCF equations have been derived with the help of Segal’s partition-basis-set technique; these equations can be used for the calculation of the potential curves of many organic reactions. They were applied to two typical organic reactions, and the results were compared with those obtained by CI methods. The corrections of the SCF-CI energies by the MC-SCF procedure were small for the present system.
Charge-Transfer Transitions Associated with Tricyanovinyl Aromatics
Authors: Sasaki Akira , Aihara Jun-ichi , Matsunaga Yoshio 
Published: July 2006

Abstract
Four tricyanovinyl aromatic compounds were spectroscopically investigated in various phases. The solidstate spectra distinctly display both intra- and inter-molecular charge-transfer bands in the visible region. The formation of the charge-transfer self-complex is, however, markedly hindered in the fluid phases. The dual charge-transfer properties were also examined for these compounds.
The Infrared Intensities of Stretching Fundamentals in Gaseous and Crystalline Cyanoacetylene
Authors: Uyemura Masakatsu , Maeda Shiro 
Published: July 2006

Abstract
The absolute intensities of the stretching fundamentals of cyanoacetylene and cyanoacetylene-d were measured in gaseous and crystalline (77 K) states. As had been expected from the previous result for hydrogen cyanide, a striking intensity increase upon crystallization was observed not only for νCh(Cd) also for the other fundamentals. The observed intensities were reduced to dipole-moment derivative with respect to the internal coordinates, ∂μ⁄∂r. Then, by taking advantage of the strictly linear geometry of hydrogen-bonded chains in the crystals, it was demonstrated that the derivative with respect to the hydrogen-bonded distance, [∂μ⁄∂rN···H], was primarily responsible for the remarkable change in ∂μ⁄∂r; this was in accordance with the previous conclusion for hydrogen cyanide. A discrepancy from this view which appeared for ∂μ⁄∂r3 was interpreted as being mainly caused by the vibronic behavior of π-electrons.
Deuterium Isotope Effects on the Redex Decomposition of Hydroxymercurated Propene and 2-Butenes in an Aqueous Solution
Authors: Shinoda Sumio , Saito Yasukazu 
Published: July 2006

Abstract
Kinetic deuterium isotope effects on the redox decomposition of hydroxymercurated propene, cis-, and trans-2-butenes in an aqueous solution (CH3CH(OH)CHRHg+→CH3COCH2R+Hg(0)+H+; R=H, CH3) were determined by following the reaction in situ by means of PMR spectroscopy. Taking advantage of the PMR characteristics, the identity of the reaction conditions was confirmed by comparing the rates for the reactant mixtures (e.g., CH3CH(OH)CH2Hg++CH3CD(OH)CH2Hg+). The mercurials, deuterated on either β-carbon (CH3CD(OH)CH2Hg+, CH3CD(OH)CHCH3Hg+) or α-carbon (CH3CH(OH)CDHHg+, CH3CH(OH)CDCH3Hg+), gave primary and secondary deuterium isotope effects of 1.35–1.40 and 1.17–1.19 respectively. A possible structure of the activated complex was proposed in accord with the observed nature of the intramolecular hydrogen shift.
Ligand-Ligand Interaction in [Zn(1,10-phenanthroline)2(H2O)2](NO3)2 and [Zn(2,2′-bipyridyl)3](NO3)2
Authors: Ohno Takeshi , Kato Shunji 
Published: July 2006

Abstract
The interaction between ligands in the excited state and in the ground state was examined by exploring the photophysical behaviors of ligands in the bis- and the tris-bidentate complexes. Although no exciton splitting was observed in the absorption spectra of [Zn(bipy)3](NO3)2 and [Zn(phen)2(H2O)2](NO3)2 at 77 K, the fluoresccence yields of both complexes increased in comparison with those of the corresponding mono-bidentate complexes. It is probable that this change is caused by a delocalization of the excited singlet state, because a variation in Franck-Condon factors and a depolarization of the fluorescence accompanied it. In addition to the ligand-ligand interaction 1,10-phenanthroline and 2,2′-bipyridyl suffered from coordination effects. They have larger fluorescence yields and smaller phosphorescence yields than the free molecules. The decrease on the transition rate of the intersystem crossing is probably due to the changes in the energy levels of 1(n-π*) and 3(n-π*), caused by the metal-ligand bond using a “non-bonding” orbital in the free ligands.
Vibrational Assignments and Rotational Isomerism of Dichloroethylmethylsilane and 2,2-Dichlorobutane
Authors: Ohno Keiichi , Shiro Yuji , Murata Hiromu 
Published: July 2006

Abstract
The vibrational spectra of dichloroethylmethylsilane and 2,2-dichlorobutane have been measured. The vibrational assignments of these molecules have been made in relation to the rotational isomerism. The normal vibration calculations based on the modified Urey-Bradley force field have been carried out and have confirmed for both molecules that, in the liquid state, the trans and gauche isomers coexist, while the trans isomer alone persists in the crystalline state.
The Crystal Structure of Dichlorobis(acetoxime)palladium
Authors: Kitano Yukishige , Kobori Kiyotomi , Tanimura Masamitsu , Kinoshita Yukio 
Published: July 2006

Abstract
The crystal structure of dichlorobis(acetoxime)palladium, PdCl2(C3H6NOH)2, has been determined from three-dimensional single-crystal X-ray photographic data. The crystals belong to the monoclinic system (space group P21/a), with two formula units in a cell with dimensions: a=8.709±0.007, b=13.996±0.005, c=4.756±0.006 Å, and β=95.60±0.05°. The structure was established by the heavy-atom method and was refined by the block-diagonal least-squares procedure. The Pd atoms are spaced at intervals of 4.76 Å along the c-axis and have a trans planar coordination, with two Cl atoms at 2.30 Å and two N atoms of the oxime groups at 2.03 Å. The oxime plane is twisted about the Pd–N bond by 72.7° from the coordination plane defined by the Pd, Cl, and N atoms. The complex molecules are hydrogen-bonded with each other in strings of an indefinite length along the c-axis, and the hydrogen-bond distance between the O atom of the oxime and the Cl atom is 3.07 Å.
The Effect of Organic Additives on the Micelle Formation of Dodecylammonium Halides in Aqueous Solutions
Authors: Miyagishi Shigeyoshi 
Published: July 2006

Abstract
The critical micelle concentration (CMC) of dodecyl ammonium halides and the degree of dissociation of the micelle (α) of dodecylammonium chloride were determined as functions of the concentrations of the organic additives by measuring the conductivity and the emf of the following cell: calomel/1 M-KCl/sample solution/AgCl, Ag. The CMC was raised more in the presence of acetone and dioxane than in that of acetamide, formamide, urea, and methanol, and was diminished by adding alcohols (C2–C4). The effect of the alcohols on CMC decreased in the order of the diminished hydration of the counterion, acetone and dioxane were considered to affect the dodecylammonium iodide solution specifically. The dissociation of the micelle was enhanced in the presence of organic additives. Further, we estimated the solubilized amount of the additives from the degree of dissociation of the micelle and attempted to make quantitative estimation of the increment of CMC produced by organic additives.
The Thermal Reaction of Hydrogen and Nitric Oxide
Authors: Tadasa Kohji , Imai Naomi , Inaba Tetsuo 
Published: July 2006

Abstract
The kinetics of the H2–NO pyrolysis was studied at 400°C; the reaction was found to be first-order in H2 and to be independent of NO. It is suggested that the reaction proceeds by means of a free-radical chain mechanism: H2+NO(surface)→HNO+H(1), H+NO\ightleftharpoonsHNO (2), 2HNO→2OH+N2 (3) OH+H2→H2O+H(4) and 2HNO→H2O+N2O(5). This reaction scheme resembles that proposed for the CH2O–NO pyrolysis at 500°C except for the initiating step (1), which takes place on the wall of the vessel in the H2–NO pyrolysis.
Interaction between Water and Hydroxylated Surface of Silica-Alumina
Authors: Morimoto Tetsuo , Nagao Mahiko , Imai Junichiro 
Published: July 2006

Abstract
The interaction between water and the fully-hydroxylated surfaces of silica,alumina and silica-alumina has been investigated by measuring the physisorption isotherms of water at three temperatures and by computing the isosteric heat of adsorption and the site energy distribution therefrom. The number of adsorption site evaluated on the surfaces of each of the two component oxides decreases exponentially with the increase in the site energy, whereas that of the silica-alumina samples gives a peak at a relatively high energy region, suggesting the presence of strong water-physisorption sites characteristic to silica-alumina. These results can be elucidated on the basis exponentially of the postulation that new sites having protonic acid character appear when the two component oxides contact with each other, as described previously. Furthermore, it is found that the strength of such new sites for physisorption of water increases with decreasing content of alumina in silica-alumina.
Phase Transition of Solid Hexabromoethane
Authors: Koide Tsutomu , Tsujino Masami , Sawada Kazuhiro , Oda Tsutomu 
Published: July 2006

Abstract
The phase transition point of solid hexabromoethane was found at 177°C, above which the crystal is a body centered cubic lattice with two molecules in a unit cell, having a cell length of 7.80 Å at 185°C. From an analysis of entropy change, it seems that random orientations of the molecular axis would occur at the transition point. The influence of halogen substitution is discussed. It was concluded that the phase transition will be dominated mainly by the geometrical properties of the molecules.
Apparent Dipole Moments and Dielectric Relaxation Times of 1,4-Benzoquinone and Its Derivatives in Solutions
Authors: Nagai Tohru , Takahashi Hiroaki , Higasi Keniti , Sutton Leslie E , Waddington David 
Published: July 2006

Abstract
Atom polarisations, apparent dipole moments and dielectric relaxation times of 1,4-benzoquinone in various solvents were determined together with those of some of its derivatives in benzene solution. Solvent effects on the apparent dipole moments of 1,4-benzoquinone and its derivatives were examined in comparison with the absorption spectra in the submillimetre region.
Transition-metal Complexes of Pyrrole Pigments. XI. Zinc(II) Chelates of Some Dipyrromethenes
Authors: Murakami Yukito , Sakata Kazunori 
Published: July 2006

Abstract
The zinc (II) chelates of five dipyrromethenes which have methyl substituents to a various extent, as well as that of 5,5′-diphenyldipyrromethene, have been prepared. The behaviors of methyl resonances upon metalcoordination were classified into three cases: (1) a down-field shift, but not greater than that of the corresponding ligand hydrochloride (3,3′-CH3); (2) nearly no change in chemical shift (4,4′-CH3); and (3) a profound up-field shift, the methyl resonance of the corresponding ligand hydrochloride showing a down-field shift on the contrary (5,5′-CH3). A marked change in chemical shift for the methine proton upon zinc(II)-coordination is related to conjugation in the chelate ring–the presence of aromaticity. As a whole, methyl resonances for the zinc chelates are consistent with the tetrahedral coordination geometry. Electronic absorption peaks for the zinc chelates, which were located in the lowest energy region with the highest intensity, were assigned to the intra-ligand π→π* transition and the metal→ligand charge-transfer as well. Vibrational absorption bands appearing in the 1600 cm−1 range and in the 400–350 cm−1 region have been assigned to the skeletal stretching mode of the dipyrromethene moiety and the metal-ligand stretching mode, respectively, for the zinc chelates.
Studies of the Substituent Effect on the Stability Constants of Bis(2-hydroxy-4 or 5-substituted acetophenonato)copper(II)
Authors: Haruta Masami , Yoshida Zen-ichi , Ogoshi Hisanobu 
Published: July 2006

Abstract
The dissociation constants of eleven 2-hydroxy-4 or 5-substituted acetophenones were determined in a 22.5% water–dioxane-mixed solvent system at 25 and 40°C by potentiometric titration. They were then discussed in terms of the electronic effect of the substituents and the linear-free-energy relationship. The stability constants bis(2-hydroxy-4 or 5-substituted acetophenonato)copper(II) were also determined under the same experimental conditions; a linear relationship between the dissociation constants and the stability constants was obtained for bis(2-hydroxy-4 or 5-substituted acetophenonato)copper(II). No significant difference has been found in the effects of 4- and 5-substituted groups on the stability constants.
ESR and Optical Absorption Studies of Various Bis(N-salicylidenealkylaminato)copper(II) Complexes with Tetrahedrallydistorted Coordination Geometry
Authors: Yokoi Hiroshi 
Published: July 2006

Abstract
The ESR and visible absorption spectra of a number of bis(N-salicylidenealkylaminato)copper(II) complexes with different kinds of alkyl groups were measured in toluene. The coordinations of these complexes in toluene are distorted towards a tetrahedral geometry to varying extents; the relationship between the degree of the distortion and the ESR and visible absorption parameters was systematically investigated. Especially, the experimental fact that the absolute values of the hyperfine coupling constant with the copper nucleus decrease with an increase in the degree of distortion was discussed. A configurational equilibrium between two species with different degrees of the distortion was found to exist for the complexes with R=isopropyl and cyclohexyl in toluene.
The Gas-chromatographic Behavior of Perhaloalkanes
Authors: Iwata Ren , Makide Yoshihiro , Tominaga Takeshi 
Published: July 2006

Abstract
The retention indices of perhaloalkanes (perbromochlorofluoroalkanes, etc.) were measured by using a gas chromatograph with a squalane, Silicone DC 550, or Methoxy polyethylene glycol 350 column, and the correlation of the retention index with various physicochemical parameters was investigated. The retention index was found to correlate linearly with the composition of the halogen atoms in the perhaloalkane molecules; the correlation diagram appears to be of special analytical importance. The relationship between the retention index and the boiling point was also studied. The retention index was correlated linearly with the molar refractivity of the perhaloalkanes, irrespective of the polarity of the columns. The molar refractivity appears to be the inherent parameter which is most adequate for considering the regularity of the retention index. The effect of the polarity of the stationary phase on the retention index was also investigated.
Synthesis of Dimeric and Trimeric 2-(p-Tolyloxy)ethyl Acetate-Formaldehyde Polymer Model Compounds
Authors: Ninagawa Akira , Matsuda Haruo , Matsuda Sumio 
Published: July 2006

Abstract
The dimeric and trimeric 2-(p-tolyloxy)ethyl acetateformaldehyde polymer model compounds and the halogenated compound of the dimer were synthesized. 2,2′-Methylenebis(5-methyl-1,2-phenyleneoxy)diethyl acetate was synthesized by the reaction of 2-(p-tolyloxy)ethyl acetate with formaldehyde in acidic media. 2-[2-(2-Acetoxyethoxy-3-chloro-5-methylbenzyl)-4-methylphenoxy]ethyl acetate was prepared by the reaction of 6-chloro-4,4′-dimethyl-2,2′-methylenediphenol with 2-chloroethanol, followed by treatment with acetic anhydride, and 2-[2,6-bis(2-acetoxyethoxy-5-methylbenzyl)-4-methylphenoxy]ethyl acetate from 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol.
Dopaquinone and Related Compounds. The Reaction with Cyclopentadiene
Authors: Omote Yoshimori , Komatsu Toshihiko 
Published: July 2006

Abstract
The trapping of o-quinones produced during the oxidation of 4-substituted catechols(I, R=CH3, CH2CH2CO2H, CH2CH2NH3Br, CH2CH(NH3Cl)CO2CH3) in the presence of cyclopentadiene affords adducts, which are changed into 8-substituted 5,6-diacetoxy-1,4-dihydro-1,4-methanonaphthak nes(IV, R=CH3, CH2CH2CO2H, CH2CH2NHCOCH3, CH2CH(NHCOCH3)COCH3) by treatment with acetic anhydr de-pyridine Dopaquinone (IIe) is trapped with cyclopentadiene, followed by acetylation and methylation with acetic anhydride–pyridine–methanol (13 : 2 : 2) to give the N-acetyl-2-(5,6-diacetoxy-1,4-dihydro-1,4-methanonaph-thyl-8)-l-alanine methyl ester (IVd).
Reactions of Group IV Organometallic Compounds. XXX. Stepwise Addition of Isocyanates and Isothiocyanates with N-Trimethylstannyl(diphenylmethylene)amine
Authors: Suzuki Hiroharu , Itoh Kenji , Matsuda Isamu , Ishii Yoshio 
Published: July 2006

Abstract
Stepwise addition of two isocyanates to N-trimethylstannyl(diphenylmethylene)amine, Ph2C=NSnMe3, gives 3,4-dihydro-1,3-dialkyl-4,4-diphenyl-6-trimethylstannoxy-1,3,5-triazin-2(1H)-one (II) by a polar [4+2] cycloaddition of the 1/1 adduct and the second isocyanate. The isothiocyanate adducts of Ph2C=NSnMe3 react with either isocyanates or isothiocyanates to yield the corresponding consecutive insertion products (IV).
Synthesis of Butirosin B and Its 3′,4′-Dideoxy Derivative
Authors: Ikeda Daishiro , Tsuchiya Tsutomu , Umezawa Sumio , Umezawa Hamao 
Published: July 2006

Abstract
The total synthesis of butirosin B (5) is described. Its 3′,4′-dideoxy derivative (11) has been synthesized, a cyclic carbamate derivative (2) being used as the key compound. The dideoxy derivative (11) was prepared by hydrogenation of a 3′,4′-unsaturated derivative (10) obtained by the reaction of a di-O-mesyl derivative (9) with sodium iodide and zinc dust. The dideoxy derivative (11) was found to have significant activity against resistant bacteria producing phosphotransferase I.
Reactions of Ethylene with Chloroform Initiated by Amine–Ferrous Chloride System
Authors: Asahara Teruzo , Sen\={o} Manabu , Ohtani Noritaka 
Published: July 2006

Abstract
The reactions of ethylene with chloroform initiated by alkylamine-ferrous chloride systems were examined in detail. Two main products, α,α,α-trichloroalkanes (I) and α,α,ω-trichloroalkanes (II), were obtained. Their composition was independent of the kind of amine but dependent upon the total carbon number of alkylamine. When amines having higher alkyl groups were used, the main product was α,α,ω-trichloropropane (II-1). When lower alkylamines were used, the main products were α,α,α-trichloroalkanes which contained considerable amounts of higher telomers. The results support the view that the reactions proceed according to the “caged free radical” process.
Thiocarbonyl Ylides. Attempted Preparation and Related Reactions
Authors: Mitamura Shuichi , Takaku Masaaki , Nozaki Hitosi 
Published: July 2006

Abstract
The attempted preparation of thiocarbonyl ylides (I) by the proton abstraction of thiouronium salts (III) has disclosed a fast isomerization of I to enethiols (V) (Y=H) and an alternative desulfurization to enediamines (VII) (Y=Ph), the by-products being olefins (VIII) and sulfides (IX). The second route to I examined consists of the reaction of tetramethylthiourea (II) with diazomalonate, which gives rise to enediamine (VIIg). Rotation about the C=C bond of enediamines is discussed on the basis of IR and NMR spectra.