bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Reaction Dynamics–The Study of Molecular Reactivity and Disequilibrium
Authors: Levine Rephael David 
Published: July 2006

Abstract
Recent progress in molecular reaction dynamics is discussed with special reference to the selectivity in the reactivity and the specificity in product formation. Topics considered in some detail include dynamical aspects of stereochemistry, rotational state distributions in reactive collisions and intramolecular dynamics of larger molecules. The conceptual foundations of the thermodynamic-like approach to molecular disequilibrium are considered.
Synthesis of Homoiceane (Tetracyclo[6.3.1.12,7.04,10]tridecane) and 3,13-Dehydrohomoiceane (Pentacyclo[7.3.1.02,4.03,8.05,11]tridecane) through Homo-Diels–Alder Reaction
Authors: Yamaguchi Ryohei , Ban Masakazu , Kawanisi Mituyosi 
Published: July 2006

Abstract
Homo-Diels–Alder reaction of tricyclo[5.3.1.04,9]undeca-2,5-diene with maleic anhydride proceeds very nicely in refluxed o-dichlorobenzene to give a single cycloadduct in 81% yield. The stereochemistry of the adduct is determined to be exo by leading to the exo-dimethyl ester and comparing it with the endo-dimethyl ester which is prepared by homo-Diels–Alder reaction of the above diene with dimethyl acetylenedicarboxylate followed by catalytic hydrogenation. Basic hydrolysis of the cycloadduct followed by oxidative decarboxylation with Pb(OAc)4 in pyridine affords 3,13-dehydrohomoice-5-ene, catalytic hydrogenation of which gives 3,13-dehydrohomoiceane. Photoinduced intramolecular [π2+σ2] cycloaddition of 3,13-dehydrohomoice-5-ene produces the compound which contains two cyclopropane rings in its rigid structure. When this strained cage compound is treated with Pd-black under H2, hydrogenolysis of the two cyclopropane rings takes place simultaneously to afford homoiceane.
The Effect of the Wettability of the Injection Nozzle on the Size of Oil Droplets in Water
Authors: Ogino Keizo , Ohki Hiroshi , Abe Masahiko , Hirano Jiro , Funada Tadashi 
Published: July 2006

Abstract
The effect of the wettability of an injection nozzle on the size of oil droplets in water has been studied. Dodecane as an oil was dispersed into a continuous water phase through various polymers attached to the top of each single nozzle. The polymer filters used were polyethylene (PE), poly(vinyl chloride) (PVC), poly(vinyl alcohol) (PVA), cellophane (CP), and cotton (CT). The hydrophilic cotton filter is found to be more effective as the injection nozzle than any other hydrophobic polymer filter tested to disperse smaller oil droplets of dodecane into the continuous water phase. The droplet size is reduced with an increase in the hydrogen-bonding force of the polymer-filter surfaces. This may be attributed to the strong adhesion tension between the water molecules and hydrophilic groups of the polymer surface.
Proton NMR Spectra of Methyl Alkanoates in Aromatic Solvents
Authors: Hoshino Takashi , Imamura Yoshio 
Published: July 2006

Abstract
The splitting of methylene peaks in 1H NMR spectra was studied for long-chain methyl alkanoates in 1-chloronaphthalene as a function of the carbon number, nc, of alkyls. With increase in nc, the singlet peak of methylene is first split into a doublet and then into a triplet.
Potentiometric Study of Cadmium(II) Halide and Thiocyanate Complexes in Methanol. Determination of Thermodynamic Stability Constants of Third and Fourth Complexation Step
Authors: Soe Khin Nwe , Doe Hidekazu , Kitagawa Toyokichi 
Published: July 2006

Abstract
The stability constants, K3 and K4 of [CdIIXn]2−n (X−=Cl−, Br−, I−, NCS−) complexs in methanol have been determined by X− ion measurements with Ag–AgX and NCS− ion selective electrodes at 25 °C.
Selective Reduction of Carbon–Carbon Double Bonds with an NAD(P)H Model–Acetic Acid System
Authors: Inoue Yoshio , Imaizumi Shin , Itoh Hiromitsu , Shinya Takao , Hashimoto Harukichi , Miyano Sotaro 
Published: July 2006

Abstract
The carbon–carbon double bond in conjugated nitro and certain carbonyl compounds was reduced smoothly and selectively by Hantzsch ester (HEH), an NAD(P)H model, in the presence of a small amount of acetic acid.
The 19F Solid-State High-Resolution Nuclear Magnetic Resonance Study of K2SiF6, K2GeF6, and K2SnF6
Authors: Yoshioka Yoshichika , Nakamura Nobuo , Chihara Hideaki 
Published: July 2006

Abstract
High-resolution 19F NMR experiments were carried out on K2SiF6, K2GeF6 and K2SnF6, and the chemical shift shielding tensors were determined. In all three substances, the shielding tensors are axially symmetric, and the most shielded direction is parallel to the MF (M=Si, Ge, and Sn) bond. The values of the shielding tensor elements (σ⁄⁄ and σ⊥) change systematically from K2SiF6 to K2SnF6, except for the σ⊥ component of K2SiF6, which is very large compared with those in the Ge and Sn-complexes. The analysis of σ’s by a simple MO treatment indicates that π-backbonding is the strongest in the Si-F bond, probably because of the extraordinarily low electronegativity of Si. At room temperature, the reorientation of MF62− anions is rapid enough to average out the shielding tensor components in the Si and Sn-complexes.
Hopping Phenomena of [1-14C]Octadecanoic Acid Molecules at the Surface of the Langmuir–Blodgett Film Regarded as an Extremely Thin Crystal
Authors: Iwahashi Makio , Itoh Kiyoharu , Ohshima Katsumi , Seimiya Tsutomu , Yoshida Akira , Kobayashi Koichi , Takaoka Kei 
Published: July 2006

Abstract
The desorption of [1-14C]octadecanoic acid molecules in vacuo from a Langmuir-Blodgett film, which is regarded as an extremely thin crystal, was studied by using three kinds of radioactive samples containing ten molecular layers: The first sample was labeled at the tenth (the outermost) layer; the second one, at the ninth layer and the third one, at both the ninth and tenth layers. From the initial slopes in the desorption curves for these samples it is suggested that most of the acid molecules desorb from the tenth layer and some acid molecules desorb as a dimer consisting of a pair of molecules from the ninth and tenth layers. The scanning electron micrographic observations were carried out for nonradioactive samples stored for a week at 298.2 or 278.2 K under atmospheric pressure; it was concluded that the fatty acid molecules jump back and forth between a boundary (stagnant) layer and the surface of the LB multilayer and coagulate into micron-size crystals.
The Brillouin Scattering of Highly Viscous Liquids-Triacetin and Propylene Glycol Diacetate
Authors: Hashitani Ryuki , Matsui Hirohito , Koda Shinobu , Nomura Hiroyasu 
Published: July 2006

Abstract
The sound velocities of triacetin and propylene glycol diacetate were measured by means of Brillouin scattering in the temperature range from 200 to 350 K. The velocity dispersions due to the structural relaxation were observed in the gigahertz region. The relaxation behaviors could not be interpreted by the empirical equation proposed by Barlow et al., which holds in megahertz region and also the relaxation curves were located in higher frequency region than those predicted by the Maxwell model. The relaxation curves were well reproduced by single relaxation equation. In the temperature ranges of relaxation region, the temperature dependences of viscosity were expressed by Arrhenius’ viscosity equation. The relaxation behaviors can be interpreted in terms of the weak cooperative motions of molecules.
Spectroscopic Studies on the Intramolecular Hydrogen Abstraction Reactions of n-Alkyl Anthraquinone-2-carboxylates
Authors: Tanimoto Yoshifumi , Uehara Megumu , Takashima Masanobu , Itoh Michiya 
Published: July 2006

Abstract
Chain length dependence of the intramolecular hydrogen abstraction reaction of n-alkyl anthraquinone-2-carboxylates (AQ-n, n=2–20) has been studied by steady-state photolysis, phosphorescence, laser flash photolysis, and two-step laser induced fluorescence spectroscopies. All the results indicate that the excited triplet of the anthraquinone chromophore abstracts a hydrogen atom from its methylene side chain, whose rate increases with increasing chain length. The rate constant of AQ-8 is 1×104 s−1 and the increase in the rate is about 1.5×104 s−1 per one additional methylene unit for n≥10.
Seasonal Movements of Phosphorus and Iron Compounds, Dissolved Hydrogen Sulfide, and Others in Anoxic Seawater at Lake Hamana
Authors: Ichinose Norio , Adachi Kyoko , Mitsui Mina , Shimizu Chiaki , Okamoto Ken , Kurokura Hisashi , Inui Takuo , Tamura Hisae 
Published: July 2006

Abstract
The sea bottom in the vicinity of the center of Lake Hamana in Japan forms a sea basin, and anoxic seawater appears in this bottom layer in summer. We examined the seasonal movements of phosphorus and iron compounds, dissolved hydrogen sulfide, and others in this anoxic seawater with a view to investigating their elution processes from the sediments of the sea basin into the anoxic seawater. Some parts of the elution phenomena of these components from the sediments of the sea basin in Lake Hamana into the anoxic seawater in summer will be described in the present work.
Molecular Structures of cis-[Co(CN)2(acac)(dppe)] and trans(C,N)-[Co(CN)2(acac)(edpp)]·H2O and Trans Influence of Phosphine and Cyanide Ligands
Authors: Kita Masakazu , Kashiwabara Kazuo , Fujita Junnosuke 
Published: July 2006

Abstract
Molecular structures of cis-[Co(CN)2(acac)(dppe)] (a) and trans(C,N)-[Co(CN)2(acac)(edpp)]·H2O (b) have been determined by X-ray analysis, where acac, dppe, and edpp denote an acetylacetonate ion, 1,2-bis(diphenylphosphino)ethane and (2-aminoethyl)diphenylphosphine, respectively. Crystal data for a: monoclinic, P21⁄a, a=13.975(2), b=19.709(2), c=11.575(2) Å, β=109.71(1)°, V=3001.5(6) Å3, Z=4, and R=0.049. Crystal data for b: monoclinic, P21⁄c, a=17.870(3), b=7.354(2), c=16.709(3) Å, β=105.45(2)°, V=2116.5(5) Å3, Z=4, and R=0.056. The Co–O bonds trans to the phosphine and the cyanide ligands are longer, respectively, by ca. 0.06–0.08 Å and ca. 0.03–0.05 Å than those usually found in Co(III)–acac complexes such as [Co(acac)3], indicating stronger trans influence of the former than the latter.
Skimmiarepin A and B, Two New Insect Growth Inhibitory Triterpenoids from Skimmia japonica Thunb. var. intermedia Komatsu f. repens (Nakai) Hara
Authors: Ochi Masamitsu , Tatsukawa Akira , Seki Naoki , Kotsuki Hiyoshizo , Shibata Kozo 
Published: July 2006

Abstract
Two new triterpenoids, skimmiarepin A and B, which both exhibit an insect growth inhibitory activity against the silkworm, Bombyx mori L., have been isolated from the leaves and the fruit of Skimmia japonica Thunb. var. intermedia Komatsu f. repens (Nakai) Hara. Their structures have been determined by extensive 2D NMR studies and chemical methods.
Retentive Solvolysis. 16. Reinvestigation of the Retentive Phenolysis of 1-Phenylethyl Chloride. The Mechanism and the Structure of Ion Pair Intermediate
Authors: Kinoshita Tomomi , Ueno Takuya , Ikai Keizo , Fujiwara Masataka , Okamoto Kunio 
Published: July 2006

Abstract
The effect of added aniline on the polarimetric (kp) and titrimetric rate constants (kt) has been reexamined for the phenolysis of 1-phenylethyl chloride (RCl) in phenol–benzene (1:1 w/w). The kp–kt plot against the aniline concentrations exhibited the pattern C, instead of A which was the previous results in our laboratory. It has been revealed that the previous rate constants at the lower aniline concentrations, including the case of absence of aniline, were underestimated due to overlooking the reverse reaction caused by the liberated hydrogen chloride. The pattern C indicates that the first ion pair intermediate, not the second one, is nucleophilically attacked by solvent phenol molecule. The major products were the partially retained o-RC6H4OH, the partially inverted p-RC6H4OH, together with the partially retained ROPh. The same kp–kt pattern C has been observed for the competitive solvolysis of RCl in phenol–methanol (85:15 w/w), which produced the partially retained ROMe and ROPh, the partially inverted o- and p-RC6H4OH, and styrene. Such stereochemical outcomes for both solvolyses demonstrate that the major first ion pair intermediate should be a rear-side-shielded ion pair intermediate.
Reaction of 2-Hydroxyacetophenones with Thionyl Chloride in the Presence of a Catalytic Amount of Pyridine
Authors: Ali Syed Mashhood , Ilyas Mohd , Tanimoto Shigeo 
Published: July 2006

Abstract
Reaction of 2-hydroxyacetophenone (5) with excess thionyl chloride in the presence of a catalytic amount of pyridine at room temperature afforded a thiirane 6, while 2-hydroxy-4-methoxyacetophenone (7) furnished 8 when subjected to almost identical conditions. The products were characterized by microanalyses data and spectroscopic techniques including the mass spectroscopy. Plausible mechanisms for the conversions have been proposed in the light of available literature.
The Retardation of Methanol Oxidation at a Platinum Electrode in an Acid Solution
Authors: Matsui Hiroshi 
Published: July 2006

Abstract
The rate retardation of the oxidation of methanol at the potential range of about 0.65–0.8 V vs. a reversible hydrogen electrode on a platinum electrode in 0.5 mol dm−3 H2SO4 was studied. The rate retardation of the overall oxidation was caused by that of the oxidation, Reaction D, not via COad. From the relationship among the rate of Reaction D, the COad coverage, and the potentials, three types of rate retardation were found out: Type 1– Reaction D is not accelerated by the potential, and the rate of the reaction is determined by the COad coverage and the methanol concentration. Type 2– the rate of Reaction D decreases at stationary COad coverages as the oxidation is prolonged. Type 3– the rate decreases at COad coverages close to the limiting value. It is proposed that Types 1 and 2 of the rate retardations take place when the adsorption of methanol molecules is rate-determining, and when the formaldehyde and formic acid formed from methanol are accumulated in the vicinity of the electrode, respectively. Type 3 of the rate retardation has been explained in a preceding paper in terms of the aggregate damaging effect of COad.
The Addition Effect of CH3Br and CH3Cl on Ignition of CH4 by Shock Wave
Authors: Takahashi Kazuo , Inomata Tadaaki , Moriwaki Takao , Okazaki Satiko 
Published: July 2006

Abstract
Ignition delay times were measured in the CH4–CH3X (X: Cl or Br)–O2 system diluted in Ar using a shock tube. The times were shorter than those without CH3X, indicating that CH3X accelerates the ignition of CH4. A theoretical model including 8 elementary reactions concerning CH3X, with a CH4 oxidation mechanism consisting of 93 reactions, was used to examine the role of halogen for the ignition. The compounds containing Br formed a chain reaction with CH4 and accelerated the decomposition of CH4, while CH3Cl acted only as a fuel which was easily decomposed.
The Magnetic Properties of the Copper(II) Alkanoate Adducts with Benzimidazole and Related Nitrogen Donors
Authors: Emori Shuji , Kurihara Hikari , Muto Yoneichiro 
Published: July 2006

Abstract
Various copper(II) alkanoate adducts with benzimidazole, N-acetylbenzimidazole, and benzoxazole have been prepared. The influence of the hydrogen bonded structure in the benzimidazole adducts on their magnetic properties are discussed.
The Cathodic Desulfonylation of 1-Ethoxycarbonyl- and 1-Cyano-1-(p-tolylsulfonyl)-2-phenylethenes at the Mercury Electrode in Nonaqueous Solvents
Authors: Kunugi Akira , Abe Kyo 
Published: July 2006

Abstract
The cathodic reduction of 1-ethoxycarbonyl-1-(p-tolylsulfonyl)-2-phenylethene in MeCN and DMF is characterized by the selective elimination of the p-tolylsulfonyl group, resulting in the formation of ethyl (E)-cinnamate in good yields, in the presence of such efficient proton donors as benzoic acid and acetic acid. On the other hand, the cathodic desulfonylation of 1-cyano-1-(p-tolylsulfonyl)-2-phenylethene proceeds with low efficiencies, even in the presence of acetic acid and benzoic acid.
Photochemical Generation of μ-Amido-μ-peroxo-bis[bis(ethylenediamine)cobalt(III)] Complex from the Corresponding μ-Hyperoxo Complex in Neutral Aqueous Solution
Authors: Shinohara Nobuyoshi , Kose Emiko , Ohkubo Wataru 
Published: July 2006

Abstract
A μ-amido-μ-hyperoxo complex, [(en)2Co(NH2,O2−)Co(en)2]4+, was found to generate the corresponding μ-peroxo complex, together with mononuclear cobalt(III) complexes upon irradiation with near-ultraviolet light in a neutral aqueous solution. The result is different from that obtained in an acidic aqueous solution, in which the products are [Co(NH3)(en)2(H2O)]3+ and Coaq2+. The photochemical reaction mechanisms are discussed.
The Structure and Absolute Stereochemistry of a Halogenated Chamigrene Derivative from the Red Alga Laurencia Species
Authors: Suzuki Minoru , Kurosawa Etsuro , Furusaki Akio 
Published: July 2006

Abstract
The structure of a halochamigrene derivative, 2,10-dibromo-3-chlorochamigran-7-en-9-ol, isolated from the red alga Laurencia species has been determined by spectral and chemical methods as well as X-ray crystallographic analysis of the ketone derivative. Furthermore, the conformations of this compound and its derivatives are briefly discussed.
XRD Characteristics of Na–ZSM-5 Synthesized from an Organic-Free System
Authors: Dai Feng-Yuen , Suzuki Minoru , Takahashi Hiroshi , Saito Yasukazu 
Published: July 2006

Abstract
XRD profiles of as-synthesized Na– and TPA–ZSM-5 were not identical. They became similar to each other, however, when both zeolites were converted into organic-free or organic-contained forms. In terms of the framework topology, Na–ZSM-5 resembled TPA–ZSM-5 but differed from so-called ZSM-8. SEM images revealed the Na–ZSM-5 crystal to exhibit a hexagonal-lath-shaped morphology. Due to the preferred orientations, the intensities of (0k0) and (h0l) reflections were intensified and diminished, respectively. The hexagonal flat plane of the Na–ZSM-5 crystal was (010). Therefore, the 10-membered-ring straight channels were strongly indicated to penetrate perpendicularly to the hexagonal flat plane of the as-synthesized Na–ZSM-5 crystal.
1H NMR Study of the Regioisomers of Primary O-Di- and Trisubstituted α-Cyclodextrins
Authors: Matsui Yoshihisa , Fujie Masahiko , Sakate Hiroshi 
Published: July 2006

Abstract
The regioisomers of bis- and tris[C(6)-O-sulfonylated] α-cyclodextrins were converted in satisfactory yields to the corresponding C(6)-pyridinio derivatives, which afforded the characteristic splitting patterns of 1H NMR signals available for a regioisomer determination. Electrostatic repulsive interactions between the positively charged pyridinio groups play an important role in the remarkable splitting of the 1H NMR signals observed for some regioisomers.
The Preparation of Organo Colloidal Precious Metal Particles
Authors: Meguro Kenjiro , Torizuka Makoto , Esumi Kunio 
Published: July 2006

Abstract
Platinum particles were prepared by reducing the hydrogen hexachloroplatinate extracted in organic solvents from an aqueous solution by these extractants:dioctadecyldimethylammonium chloride(DDAC), trioctylmethylammonium chloride(TMAC), and trioctylphosphine oxide(TOPO). The extraction ratio of platinum(IV) increased in chloroform, isobutyl methyl ketone, and cyclohexane with an increase in the concentrations of the extractants, and then approached a constant state. The extracts were reduced by formaldehyde or benzaldehyde in the presence of water and a base (sodium hydroxide or triethylamine) for several hours at 65 °C. The platinum particles obtained in chloroform and isobutyl methyl ketone were very stable; their diameters were 15–25 Å.
The Zinc-Photosensitized Reaction of Propane
Authors: Yamamoto Shunzo , Kozasa Mitsuru , Sueishi Yoshimi , Nishimura Norio 
Published: July 2006

Abstract
The zinc-photosensitized reaction of propane has been studied at a wavelength of 307.6 nm, a temperature of 633 K and pressures from about 67 to 40000 Pa. The major products were hydrogen, methane, ethylene, and dimethylbutane, while minor products detected were propylene, isobutane, ethane, butane, and hexane. The yield of hydrogen fell off with time. The quantum yield calculated from the initial rates is about unity and almost independent of the propane pressure, while the quantum yield obtained at 20 min increased with increasing propane pressure and approached about unity at higher pressures. The methane/hydrogen ratio was always smaller than unity and was independent of the propane pressure. The yield of ethylene increased linearly with an increase in that of methane. It has been concluded that the decomposition of propane is initiated through a hydrogen atom abstraction by an excited zinc atom from both the primary and secondary hydrogen of propane. Possible mechanisms are discussed.
Molar Volumes and Electrostriction Behavior of Dicarboxylate, Disulfonate, Tartrate, and Bis(ethylenediamine)glycinatocobalt(III) Ions in Water
Authors: Yokoyama Haruhiko , Mochida Midori , Koyama Yuko 
Published: July 2006

Abstract
The ionic partial molar volumes at infinite dilution, V∞(ion), were determined for several dicarboxylate ions, disulfonate ions, tartrate ions, and [Co(gly)(en)2]2+ (gly=glycinate ion and en=ethylenediamine) from density measurements at 25°C. The values of V∞(ion) obtained for the divalent anions generally increased with their van der Waals volumes. Significant differences in V∞(ion) were observed between geometrical isomers with dicarboxylate and disulfonate ions and were attributed to those in both of electrostriction volume and the void space volume around the anions. The former volume was decreased and the latter was increased with increasing distance between two negatively charged groups in the anions. A relatively strong electrostriction behavior of the tartrate ions, compared to the dicarboxylate ions, suggested the presence of an extra electrostriction caused by hydroxyl groups. The electrostriction strength of [Co(gly)(en)2]2+ was significantly large compared to that of [Ni(en)3]2+, rather close to those of [Cr(en)3]3+ and [Co(en)3]3+, and was attributed to the dissymmetrically localized charge distribution in the [Co(gly)(en)2]2+ ion. The effective ionic radii and apparent van der Waals volumes were estimated by using Glueckauf’s equation from the ionic partial molar volume and were discussed in comparison with those calculated from the van der Waals increments of atoms.
The X-Ray Structure of Sodium trans-1,2-Cyclohexanediamine-N,N,N′,N′-tetraacetatochromate(III) 4.5-Hydrate, Na[Cr(cydta)]·4.5H2O
Authors: Kaizaki Sumio , Hayashi Mariko , Umakoshi Keisuke , Ooi Shun-ichiro 
Published: July 2006

Abstract
The crystal structure of the title compound has been determined from the X-ray diffraction data. This complex crystallizes in the monoclinic space group with unit-cell parameters of a=17.724(2), b=8.084(1), c=14.025(2) Å, β=95.06(1)°, and Z=4, and with a space group of P2⁄c. The structure converged to R=0.043 for 2898 reflections. In the complex anion, the chromium is coordinated by the sexadentate cydta ligand, producing a distorted octahedral CrN2O4 geometry. The glycinate chelates of the in-plane G(girdling) rings in the CrN2O2 plane are more distorted with respect to the Cr–O bond lengths and internal bond angles than are those of the out-of-plane R(relaxed) rings in the CrNO3 plane. This may be responsible for the lability to dissociation of the G-ring acetate chelates. A close proximity of non-bonded hydrogen atoms (ca. 1.90 Å) is found between the methylene groups in the R ring and the cyclohexane ring. There are two nonequivalent sodium ions in the unit cell, which link the cydta complex anions to form an anion layer along the c axis.