bluuebunny/crossref_metadata_2025 huggingface dataset:
Syntheses and Structure of Bis(O,O′-diethyl dithiophosphato)bis(hexamethylenetetramine)cadmium(II) and Related Adducts
Authors: Shimoi Mamoru , Ouchi Akira , Aikawa Masahiko , Sato Shoichi , Saito Yoshihiko
Published: July 2006

The title complex was synthesized, and the crystal structure was determined by means of the X-ray diffraction technique. The crystal is monoclinic; space group P21/n, a=16.310(3), b=6.777(1), c=14.576(3) Å, β=96.13(1)°, Z=2, Dx=1.58, Dm=1.55(3) g cm−3, μ(Mo Kα)=1.12 mm−1. The molecule has a center of symmetry, and a distorted octahedron is formed around the central cadmium atom; two O,O′-diethyl dithiophosphato ions (dtp) act as bidentate ligands, and each ligand forms a four-membered chelate ring with its two sulfur atoms on the equatorial plane, while two hexamethylenetetramine molecules are coordinated to the metal atom by their nitrogen atoms from the axial direction. Related adducts, Cd(II)(dtp)2·Xn, where X is a donor and n=1 or 2, were also synthesized, and their structures were compared with those of the corresponding Co(II)(dtp)2·Xn−type complexes.
A New Type of P–C and C–C Bond Cleavage Reactions in α-Trimethylsilyloxy-β-oxo Phosphonates and α-Ethoxy-β-oxo Phosphonates. The Synthesis of Unsymmetrical α-Hydroxy Ketones Utilizing 1:1 Carbonyl Adducts of Diethyl Trimethylsilyl Phosphite with Benzaldehyde
Authors: Sekine Mitsuo , Nakajima Masashi , Hata Tsujiaki
Published: July 2006

α-Lithiated diethyl α-(trimethylsilyloxy)benzylphosphonate underwent facile acylation with various acylating agents to afford the corresponding α-acylated products in good yields. On treatment of the α-acylated products with 1 M NaOH–EtOH (1:1, v/v) the P–C bond was cleaved with elimination of diethyl phosphate to give α-hydroxy ketones predominantly. On the other hand, when diethyl α-acyl-α-ethoxybenzylphosphonates were treated under the same conditions, they were rather stable and recovered. However, the prolonged alkaline treatment or the use of 4 M NaOH–EtOH (1:1, v/v) resulted in the C–C bond cleavage giving carboxylic acids and diethyl α-ethoxybenzylphosphonate in quantitative yields, respectively. The mechanisms of the above two reactions were proposed and discussed in connection with the Perkow reaction and related reactions.
The Photocycloaddition of 6-Substituted Phenanthridines to Electron-rich Olefins
Authors: Futamura Shigeru , Ohta Hiroyuki , Kamiya Yoshio
Published: July 2006

The photocycloaddition reaction of 6-substituted phenanthridines and electron-rich olefins, such as trans-anethole and phenyl vinyl ether, is described. This reaction proceeds from the 1(π,π*) states of 6-substituted phenanthridines via the exciplex to give azocine and/or azetidine derivatives in ethanol.
Silyl Phosphites. XVIII. Versatile Utility of α-(Trimethylsilyloxy)alkylphosphonates as Key Intermediates for Transformation of Aldehydes into Several Carbonyl Derivatives
Authors: Sekine Mitsuo , Nakajima Masashi , Kume Akiko , Hashizume Akio , Hata Tsujiaki
Published: July 2006

Carbonyl addition compounds of diethyl trimethylsilyl phosphite (DTMSP) with aldehydes were converted, by treatment with lithium diisopropylamide (LDA) followed by the successive alkylation and alkaline hydrolysis, to carbonyl derivatives involving aldehydes, unsymmetrical ketones, β,γ-unsaturated ketones, and carboxylic acids. β-Substituted carboxylic esters and γ-substituted lactones were prepared by use of the carbonyl addition compounds of DTMSP with α,β-unsaturated aldehydes.
Synthesis of Naturally Occurring Prenylated Benzophenones. Vismiaphenone A, Vismiaphenone B, and Isovismiaphenone B
Authors: Pathak Ved Prakash , Khanna Rajinder Nath
Published: July 2006

2,4,6-Trihydroxybenzophenone on prenylation with 2-methyl-3-buten-2-ol in the presence of (C2H5)2O·BF3 yielded 2,4,6-trihydroxy-3,5-diprenylbenzophenone (3), 2,6-dihydroxy-4-prenyloxybenzophenone, 2,6-dihydroxy-3-prenyl-4-prenyloxybenzophenone, a benzodipyran and 6-benzoyl-5,7-dihydroxy-2,2-dimethyl-3-prenylchroman. 3 on reaction with 2 moles of p-toluenesulfonyl chloride followed by methylation and detosylation gave a naturally occurring benzophenone, vismiaphenone A (12). Cyclodehydrogenation of 6-hydroxy-3,5-diprenyl-2,4-ditosyloxybenzophenone gave 8-benzoyl-2,2-dimethyl-6-prenyl-5,7-ditosyloxy-2H-1-benzopyran, which on detosylation gave another naturally occurring benzophenone, isovismiaphenone B, while cyclodehydrogenation of 3 gave vismiaphenone B, another naturally occurring benzophenone. 2,4-Dihydroxy-6-methoxy-benzophenone on similar treatment with 2-methyl-3-buten-2-ol afforded 12 directly.
The Condensation of Isatin with o-Phenylenediamine
Authors: Niume Kazuma , Kurosawa Shigeru , Toda Fujio , Hasegawa Masaki , Iwakura Yoshio
Published: July 2006

The condensation of isatin with o-phenylenediamine has been studied in various kinds of solvents. The reaction gave pure indolo[2,3-b]quinoxaline (1) in acidic solvents, while it gave a mixture containing at least two out three compounds, 1, an anil and a spiro compound, in neutral or basic organic solvents. The anil and spiro compounds were converted to 1 in the presence of acid or by heating them above their melting points. The mechanism of the formation of these compounds and the conversion could be explained by the presence of the intermediate of the adduct formed between the amino groups of o-phenylenediamine and the β-carbonyl of isatin.
The Disproportionation of cis-Bicyclo[4.3.0]nona-3,7-diene Catalyzed by Fe(CO)5 and Cp2Fe2(CO)4
Authors: Kagayama Takashi , Okabayashi Shinji , Amaike Yoichi , Matsukawa Yasuo , Ishii Yasutaka , Ogawa Masaya
Published: July 2006

cis-Bicyclo[4.3.0]nona-3,7-diene (1) was catalytically disproportionated by the use of Fe(CO)5 and Cp2Fe2(CO)4 to bicyclo[4.3.0]non-1(6)-ene (3) and indan (4). However, the same reaction catalyzed by the use of other metal carbonyls gave merely small amounts of 3 and 4, while those using Pd– and Rh–carbons yielded only 4 and the starting material, 1, respectively.
Optical Resolution of 2-(Anilinomethyl)pyrrolidine
Authors: Saigo Kazuhiko , Tanaka Jun , Nohira Hiroyuki
Published: July 2006

(±)-2-(Anilinomethyl)pyrrolidine, prepared from (±)-5-oxopyrrolidine-2-carboxylic acid, was effectively resolved into a pair of the enantiomers by fractional crystallization of its mandelic acid salt. Moreover, the preferential crystallization of its p-hydroxybenzoic acid salt was found to give both enantiomers in high optical purities by alternate seeding.
A Cyclization of Humulene by Means of a Mercuric Salt in Aceto- and Benzonitrile
Authors: Hayano Kiyoharu , Shirahama Haruhisa , Matsumoto Takeshi
Published: July 2006

Humulene was converted to 3,6-secoprotoilludane derivatives by treatment with mercury(II) trifluoroacetate in aceto- and benzonitrile.
In-vitro Clot Forming Properties of Polyelectrolyte Complexes of [2-(Diethylamino)ethyl]dextran Hydrochloride with Poly(sodium-l-glutamate) and of Sodium Carboxymethyldextran with Chitosan
Authors: Kikuchi Yasuo , Takebayashi Tsutomu
Published: July 2006

Polyelectrolyte complexes prepared at higher hydrogen ion concentrations may form clots in higher quantities than those prepared at lower hydrogen ion concentrations, irrespective of the content of anticoagulant reagents. This difference is attributable to the difference in molecular structure of polyelectrolyte complexes, especially to the presence of carboxyl groups.
Conformation en Solution des Benzile-monoximes et des Dichloro-4,4′ benzile-monoximes E et Z
Authors: Bernadou Jean , Fayet Jean Pierre , Bonnafous Monique , Mauret Pierre
Published: July 2006

Les auteurs ont synthétisé deux benzile-monoximes et deux dichloro-4,4′ benzile-monoximes. L’ introduction de deux atomes de chlore en para sur les cycles permet, par comparaison des moments dipolaires expérimentaux et calculés, de confirmer les configurations et de préciser les conformations de chaque isomère.
Hydrogenolysis and Hydrogenation of Ethylene on LaCoO3
Authors: Ulla Maria Alicia , Lombardo Eduardo Agustin
Published: July 2006

The hydrogenation and hydrogenolitic activity of LaCoO3 reported by Ichimura et al. can be rationalized in terms of the current literature by a model in which Co°, produced under reaction conditions, is the locus of catalytic activity. This interpretation disagrees with the model supported by the authors.
The Extractability of Potassium as Picrates (KPic and K(L)Pic, L: 18-Crown-6) and Its Relationship to the Properties of the Solvents
Authors: Iwachido Tadashi , Minami Masayoshi , Naito Hirohiko , Tôei Kyoji
Published: July 2006

The distribution ratios, D,of potassium between an aqueous KCl solution and 57 organic solvents (8 alcohols, 12 ketones, 6 esters, 3 ethers, and 28 hydrocarbons(24 halo- and 2 nitro-substituted and 2 unsubstituted)) were determined in the presence or in the absence of L. The presence of L markedly enhances the extractability of potassium when the halogenated hydrocarbon solvents are used, but only a slight enhancement can be observed for the oxygen-containing solvents. Among the properties showing good correlations with D, Hansen’s three-dimensional solubility parameters and Dimroth’s ET values are most satisfactory for their applicability to a wide variety of solvents.
Protection of Phosphonate Function by Means of Ethoxycarbonyl Group. A New Method for Generation of Reactive Silyl Phosphite Intermediates
Authors: Sekine Mitsuo , Mori Hiroyuki , Hata Tsujiaki
Published: July 2006

Nucleoside ethoxycarbonylphosphonates were prepared by condensation of appropriately protected nucleosides with ethoxycarbonylphosphonic acid. They were easily converted by treatment with 1 M NaOH followed by trimethylsilylation to highly reactive bis(trimethylsilyl) nucleoside phosphite intermediates which were allowed in situ to react with water, diphenyl disulfide, 2,2′-dipyridyl disulfide, and aldehydes to afford the corresponding nucleoside phosphonates, nucleoside S-phenyl phosphorothioates, nucleoside phosphates, and nucleoside α-hydroxy phosphonates in good yields, respectively. The nucleoside phosphonates were further converted to nucleosides under mild acidic conditions. Thus, the ethoxycarbonyl group proved to serve as a versatile protecting group for not only H–P(O) but also HO–P(O) and hydroxyl groups of sugars.
Structure of Rishitinone, a Valencane Stress Metabolite in Diseased Potato
Authors: Katsui Nobukatsu , Yagihashi Fujio , Murai Akio , Masamune Tadashi
Published: July 2006

The isolation and structure elucidation of the title valencane sesquiterpene, a stress metabolite produced in diseased potato tubers, are described.
Substituent Effects on the Mesophase Stability for Cholesteryl Benzoylbenzoates
Authors: Koden Mitsuhiro , Takenaka Shunsuke , Kusabayashi Shigekazu
Published: July 2006

The thermal properties of cholesteryl esters of substituted benzoylbenzoic acids were examined. The substituent effects on the thermal stability of the chloesteric phase of these esters are quite striking. For cholesteryl 4-(4′-substituted benzoyl)benzoates, the Ch-I transition temperatures are slightly influenced by an electronic effect of the substituents, because the bond direction of the substituents is tilted with respect to the long molecular axis. For cholesteryl 4-(3′-substituted benzoyl)benzoates and cholesteryl 3-(4′-substituted benzoyl)benzoates, the Ch-I transition temperatures are influenced by the polarizability anisotropy of the terminal phenyl ring, which probably gives rise to a change in the ratio of the number of more-linear isomers to the number of less-linear isomers. For cholesteryl 4-(2′-substituted benzoyl)benzoates, the substituents increase the angle between the two phenyl rings, i.e., the thickness of the benzophenone moiety, due to the repulsive interaction between the substituent(s) and ortho-hydrogens of the other phenyl ring, and therefore decrease the Ch-I transition temperature largely.
The Synthesis of Racemic Fomannoxin, Anodendroic Acid, and 5-Acetyl-2-[1-(hydroxymethyl)vinyl]-2,3-dihydrobenzofuran
Authors: Yamaguchi Seiji , Kondo Seizo , Shimokawa Keiko , Inoue Osamu , Sannomiya Michiko , Kawase Yoshiyuki
Published: July 2006

2-Isopropenyl-2,3-dihydrobenzofuran was effectively prepared by two new methods. Fomannoxin and 5-acetyl-2-[1-(hydroxymethyl)vinyl]-2,3-dihydrobenzofuran were synthesized from 2-isopropenyl-2,3-dihydrobenzofuran, while anodendroic acid was synthesized from 2-(1-hydroxy-1-methylethyl)-2,3-dihydrobenzofuran.
Multidentate Ligand Kinetics. IV. Computer Simulation of the Steady State of the Free Ligands in a Coordination Chain Reaction
Authors: Katsuyama Tetsuo , Kumai Toshihiko
Published: July 2006

The ligand-substitution reactions between two multidentate ligand complexes in the presence of free ligands proceed by means of a coordination chain-reaction mechanism. The reaction was simulated on a computer under various conditions. The character of the steady state of the free ligands in the coordination chain reaction was discussed. The conditions under which the coordination chain reaction proceeds with the steady state of the free ligands were determined. The diagrams of the time development of the free ligands were found to be useful for studies using the coordination chain reaction.
A Kinetic Study of the Interaction of Sodium Dodecyl Sulfate with Bovine Serum Albumin by Means of a Pressure-jump Method
Authors: Takeda Kunio
Published: July 2006

A single relaxation was found in the system of sodium dodecyl sulfate and bovine serum albumin using a pressure-jump method with conductivity detection. The relaxation was observed in the concentration range of the surfactant below the critical micelle concentration. The relaxation time becomes fast with the stepwise formation of a complex between them and finally attains values compatible with those in the system of the pure surfactant micelle. This suggests a correlation of the relaxation phenomena with the partial breakdown and reformation of the complex. The similarity of the complex to the surfactant micelle was discussed on the basis of the kinetic aspects of the interaction of the surfactant with the protein.
Organofluorosilicates in Organic Synthesis. XVI. Synthesis of Organopentafluorosilicates via the Diels-Alder, Ene, and Friedel-Crafts Reaction. Their Transformations to Organic Halides and Alcohols
Authors: Tamao Kohei , Yoshida Jun-ichi , Akita Munetaka , Sugihara Yoshihiro , Iwahara Takahisa , Kumada Makoto
Published: July 2006

Described herein are several representative examples of cleavage reactions of otherwise hardly accessible organopentafluorosilicates which are obtainable via the Diels-Alder reaction, ene reaction, and the Friedel-Crafts reaction of vinyl-, ethynyl-, or allyl-trichlorosilanes. The Diels-Alder reaction between vinyltrichlorosilane and o-xylylene generated in situ by debromination of α,α′-dibromo-o-xylene afforded (1,2,3,4-tetrahydro-2-naphthyl)trichlorosilane which was converted to the corresponding silicate. The silicate reacted with NBS and MCPBA to give the respective bromide and alcohol. The Diels-Alder reaction between ethynyltrichlorosilane and methyl coumalate gave a mixture of meta and para isomers of methyl (trichlorosilyl)benzoate in the ratio of 55/45, the silicate of which reacted with NBS to give two positional isomers of methyl bromobenzoate. The electronic effect of the methoxycarbonyl group on the Si–C bond cleavage was small. The silicate derived from 4-octenyltrichlorosilane which was obtained by the ene reaction between vinyltrichlorosilane and 1-hexene afforded, upon treatment with NBS, 4-octenyl bromide in the ratio of E⁄Z=83⁄17. The sterically crowded neophylsilicate obtainable via the Friedel-Crafts reaction of 2-methyl-1-propenyltrichlorosilane with benzene underwent the cleavage reaction with NBS in methanol. Neophyl bromide was formed with CuBr2 in a low yield, no product being formed arising from rearrangement of the neophyl radical.
Tris(2,2′-bipyridine)ruthenium(II)-photosensitized Reductions of Methyl Viologen and Molecular Oxygen in a Network of Water-swollen Cation-exchange Resin
Authors: Kurimura Yoshimi , Katsumata Kimiyo
Published: July 2006

The visible-light-induced reduction of methyl viologen was found to occur in water-swollen cation-exchange resin, which adsorbed both Ru(bpy)32+ and methyl viologen (RMCA resin) with the aid of triethanolamine (TEA) as a donor. With illumination, the generation of hydrogen peroxide proceeds in an oxygenated TEA solution containing RMCA resin. Hydrogen peroxide is produced via the superoxide ion, which is itself formed by the reaction of the methyl viologen radical in the resin with the oxygen molecule in the bulk of the solution. The Ru(bpy)32+-photosensitized reaction processes leading to the generation of methyl viologen radical and hydrogen peroxide in the heterogeneous systems are discussed on the basis of the results obtained.
Direct Measurement of the Interaction Energy between Solids and Gases. VIII. A High-temperature Calorimeter for the Determination of Heats of Adsorption from Room Temperature to 700 K
Authors: Tsutsumi Kazuo , Hagiwara Seiichi , Mitani Yoshio , Takahashi Horoshi
Published: July 2006

A high-temperature calorimeter of the twin conduction type was designed with the capability of measuring heats of adsorption of gases on solids in the temperature range RT to 700 K. A chromel-alumel thermopile was used as the detector and a volumetric adsorption apparatus was equipped. Its calibration and preliminary experiments on heats of adsorption of ammonia on zeolites are described.
Reactions of Chloroiron(III) Schiff Base Complexes with Superoxide Ion in Dimethyl Sulfoxide
Authors: Matsushita Takayuki , Kono Hiroshi , Nishino Mitsuru , Shono Toshiyuki
Published: July 2006

A series of monomeric chloroiron(III) complexes with the quadridentate or quinquedentate Schiff bases such as N,N′-disalicylideneethylenediamine or bis[3-(salicylideneamino)propyl]amine react with superoxide ions, O2−, in dimethyl sulfoxide to give the corresponding μ-oxo dimers. The polymeric chloroiron(III) complexes with the polymeric (oligomeric) Schiff bases derived from 5,5′-methylenedisalicylaldehyde and triamines react with O2− in dimethyl sulfoxide to give the oxygenated complexes, probably dioxygen adducts, FeIII–O2−. This is suggested by the absorption spectra and the polarographic measurements.
The Temperature Dependence of the Peak Height of the Lead Ion in Square-wave Polarography
Authors: Hatanaka Nobuko
Published: July 2006

The peak height of the square-wave (s.w.) polarogram of lead increased markedly upon the addition of anions forming insoluble compounds with lead, and the temperature coefficient of the peak height showed a negative value, different from the theoretical value in a diffusion-controlled or an electrode-reaction-rate-controlled process at the following concentrations of anions; [Cl−]=1 M, [Br−]=10−2 M, [SCN−]=10−1 M for 10−4 M lead. In the case of the addition of iodide, the s.w. peak height of lead increased at concentrations of iodide above 10−4 M for 10−4 M lead but the temperature coefficient of the peak height was always positive. Moreover, another peak due to lead appeared superimposed on the oxidation peak of iodide at a more positive potential, and this peak had a negative temperature coefficient. It was found that these phenomena were attributable to a specific adsorption of lead on mercury electrodes, induced by the foremost adsorbed anions. However in the case of the addition of iodide or in that of a high concentration of bromide or thiocyanate, the reversibility of the electrode process decreased and the temperature coefficient varied to a positive value in spite of the increase in adsorbed depolarizers.
Configuration of Alanine Part in Natural Octopine
Authors: Goto Kazuo , Waki Michinori , Mitsuyasu Nobuo , Kitajima Yasuo , Izumiya Nobuo
Published: July 2006

Octopine has a structure of N2-(1-carboxyethyl)arginine or N-(1-carboxy-4-guanidinobutyl)alanine. Configuration of the arginine part in natural octopine is determined as (S), whereas that of the alanine part has been assumed as (R). The configuration of the alanine part was concluded to be (R) by the present synthesis of (+)-octopine, which was identical with the natural one, by a sequence of reactions starting from (R)-alanine and (R)-2-bromo-5-acetamidopentanoic acid. The reaction of (R)-alanine and (R)-2-bromo-5-acetamidopentanoic acid in alkaline conditions gave N2-((R)-1-carboxyethyl)-N5-acetyl-(S)-ornithine which was converted to N2-((R)-1-carboxyethyl)-(S)-ornithine ((R),(S)-octopinic acid) by hydrolysis with hydrochloric acid. (R),(S)-Octopinic acid gave (+)-octopine ((R),(S)-octopine) by guanidination. The reaction of (S)-alanine and (R)-2-bromo-5-acetamidopentanoic acid led to give (S),(S)-octopinic acid and subsequently (+)-isooctopine ((S),(S)-octopine).
Sorption Behavior of Aromatic Compounds in Water on β-Cyclodextrin Polyurethane Resins
Authors: Kawaguchi Yoshihiro , Mizobuchi Yoshikazu , Tanaka Minoru , Shono Toshiyuki
Published: July 2006

The sorption behavior of aromatic compounds in water on β-cyclodextrin polyurethane resins was evaluated by batch and column procedures. The values of their sorption capacities obtained in the batch experiments were comparable to those of Amberlite XAD-2 and/or -7. In the column experiments, β-H6XDI-P-6.0-M showed a quantitative collection of the aromatic compounds at low concentrations, while Amberlite XAD-7 did not.
The Conversion of Methanol into Hydrocarbons over Metal Salts of Heteropolyacids
Authors: Baba Toshihide , Sakai Junya , Ono Yoshio
Published: July 2006

Metal salts of heteropolyacids are active catalysts for the conversion of methanol into hydrocarbons. Though the activity depends on the kind of metal salt, the reaction mechanism for the conversion is common to most of the metal salts, and the active centers are probably Brönsted acid centers.
Efficient Photoreduction of Methylviologen Sensitized by Chlorophyll Derivatives and Hydrogen Evolution by Visible Light
Authors: Koiso Takashi , Okuyama Masataka , Sakata Tadayoshi , Kawai Tomoji
Published: July 2006

The photoreduction of methylviologen sensitized by chlorophyll derivatives and porphines was investigated using EDTA as a reducing agent. The quantum yield of the photoreduction depends greatly on the kind of central metal ion of chlorophyll derivatives and porphines. Zn–chlorophyll-a and Zn–tetraphyenylporphine show a high quantum efficiency amounting 0.4, which is higher than that of chlorophyll-a.
A Theoretical Study of the Resonance Raman Scattering from a Molecular System. Effects of Vibronic and Nonadiabatic Couplings
Authors: Seo Katsumi , Kono Hirohiko , Fujimura Yuichi
Published: July 2006

A theory of the resonance Raman scattering (RRS) from a molecular system in which the vibronic levels of the resonance state are perturbed by both the Herzberg-Teller vibronic and the nonadiabatic coupling is developed. By using the time-independent Green-function formalism, an expression for the RRS is derived in the three-electronic-state model. The RRS cross-sections obtained are classified into four types: the pure RRS cross-section, independent of the coupling mode: the vibronically induced one, the nonadiabatically induced one, and the interference term. Assuming that the molecular system consists of a totally symmetric mode characterized by a displaced harmonic oscillator, with a nontotally symmetric mode as the inducing mode, analytical expressions for the relevant RRS cross-sections of the ns-th order vibrational transition for the totally symmetric mode are derived. Model calculations of the cross-sections indicate that, for an increasing potential displacement parameter, Δ, between the coupled states, the nonadiabatic correction to the higher-order vibrational transitions, as well as the zero-order vibrational transition, makes a significant contribution.
Reactions of Polymeric Chloromanganese(III) Schiff Base Complexes with Superoxide Ion in Dimethyl Sulfoxide
Authors: Matsushita Takayuki , Nishino Mitsuru , Shono Toshiyuki
Published: July 2006

The polymeric Mn(III) Schiff base complexes react with superoxide ions (O2−) in dimethyl sulfoxide (DMSO) to give the oxygenated complexes, while the corresponding monomeric Mn(III) complexes are reduced with O2− to the Mn(II) complexes.
Syntheses and Configurations of Copper(II) and Nickel(II) Complexes of trans-1,2-Dicyano-1,2-cyclohexanediamine
Authors: Okawa Hisashi , Kakimoto Miyuki , Izumitani Tatsuo , Kida Sigeo
Published: July 2006

Complexation of the solid and oily isomers of 1,2-dicyano-1,2-cyclohexanediamine (abbreviated as s-cychd and o-cychd respectively) with nickel(II) and copper(II) ions have been investigated. Only s-cychd formed the complexes Ni(s-cychd)2Cl2 and Cu(s-cychd)2X2 (X=Cl, Br, NO3, ClO4). Based on the configuration of the nickel complex, s-cychd was shown to be the (E)-isomer and thence o-cychd the (Z)-isomer. Configurations of the copper complexes have been dicussed on the basis of electronic spectra of DMF solution and of powder sample.
Photoredox Chemistry of Copper(II) Perchlorate in Methanolic Medium
Authors: Silva Paulo Augustro Correa da , David Pazhayirayyathu Geeverghese
Published: July 2006

Ultraviolet irradiation of copper(II) perchlorate in methanol yields copper(I) and formaldehyde as the products. The primary photoprocess is believed to be the homolytic cleavage of copper(II)-methanol bond. Secondary reactions of oxidized solvent species with copper(II), copper(I), and solvent molecules affect the product quantum yields. Variation of the quantum yield for copper(I) as a function of irradiating wavelength indicates the existence of methanol-to-copper(II) charge transfer band in the 200–250 nm region.
The Thermal Decomposition of N,O-Diacyl-N-t-butylhydroxylamines. IV. A Novel Acyloxyl Migration in N,O-Diacyl-N-t-butylhydroxylamines
Authors: Uchida Yuzuru , Kozuka Seizi
Published: July 2006

Several N,O-diacyl-N-t-butylhydroxylamines were prepared, and their thermal decompositions were studied. N-Propionyl-O-benzoyl-N-t-butylhydroxylamine gave N-t-butyl-2-benzoyloxypropanamide, together with the decomposition products, N-t-butylpropanamide and benzoic acid, upon thermal decomposition in tetralin. Similar benzyloxyl migrations were found in the thermal decomposition of N-butyryl, N-valeryl, and N-(3-phenylpropionyl) derivatives.
Steric Effect on Carbon-13 Nuclear Magnetic Resonance Shifts in Poly(vinylnaphthalene)s
Authors: Seki Kazuhiko , Mori Shinji , Imamura Yoshio
Published: July 2006

From the point of view of the rotational isomeric state for the side groups (π- and o-conformation), the steric compression effect on the 13C chemical shift of the aliphatic carbons in poly(1-vinylnaphthalene)(P1VN) and poly(2-vinylnaphthalene)(P2VN) were evaluated according to H.J. Schneider’s method. In addition to the steric compression effect, the ring current effect by the naphthyl groups in P1VN and P2VN was taken into account. The numerical results suggested that the marked higher field shifts of the methine carbon of P1VN in comparison with that of P2VN, was attributed to the strong steric compression with the 1-naphthyl group (occupied the stable π-conformation) in the same monomer units. While in the P2VN chain, the resonances of the aliphatic carbons were calculated to be in the vicinity of those of polystyrene. Naphthyl ring current contribution to 13C-NMR chemical shifts was found to be small in comparison to the dominant steric compression effect.
Thermochemical Studies on 2,4,6-Triisopropylbenzophenone and Its Photo-isomer, 3′,5′-Diisopropyl-4,4-dimethyl-3-phenyl-1,2-benzocyclobuten-3-ol. Evaluation of Magnitude of Light Energy Stored in the Latter Molecule
Authors: Inagaki Sadayasu , Murata Shigeo , Sakiyama Minoru , Ito Yoshikatsu , Umehara Yasutoshi , Hijiya Toyoto , Matsuura Teruo
Published: July 2006

Standard energy of combustion and standard enthalpy of sublimation were determined for the title compounds with static bomb combustion calorimetry and with sublimation calorimetry, respectively. Derived standard enthalpies of combustion and of formation at 298.15 K were as follows: ΔH°c(c)=−(12354.3±1.8), ΔH°f(c)=−(304.6±3.4), and ΔH°f(g)=−(189±8) kJ mol−1, respectively, for 2,4,6-triisopropylbenzophenone(1), and ΔH°c(c)=−(12440.6±1.6), ΔH°f(c)=−(218.3±3.3), and ΔH°f(g)=−(101±10) kJ mol−1, respectively, for 3′,5′-diisopropyl-4,4-dimethyl-3-phenyl-1,2-benzocyclobuten-3-ol(2). The enthalpy change for the reaction: 1(g)→2(g), of 88 kJ mol−1, which may be supposed to be the magnitude of light energy stored in the latter molecule, has been discussed.
Specific Anion Effects on Water Structure at Polypeptide Monolayer–Water Interface
Authors: Shibata Akira , Yamashita Shinsuke , Yamashita Takuya
Published: July 2006

The specific anion effects on water structure at the polypeptide monolayer–water interface were investigated. It was found that the effects of anions on increasing the film transition pressure were in the order of SCN−>Br−>Cl−>F− in line with that of those anions as breakers of water structure. The SCN− ion disrupts the hydrophobic hydration surrounding the hydrocarbon moieties of polypeptides and lipids at the interface. On the other hand, the presence of F− ion as a structure maker tends to stabilize the hydrophobic bonding. The increase of the film transition pressure on KSCN subsolution was associated with a difference in the conformation between poly(γ-benzyl l-glutamate) and poly(γ-benzyl Dl-glutamate). The infrared spectra of polymers obtained from single and mixed films were practically identical with the collapsed films in the presence and the absence of SCN− and F− ions.
Spectroscopic Properties for High-pressure Polymorphs of Calcium and Strontium Metasilicates
Authors: Machida Ken-ichi , Adachi Gin-ya , Shiokawa Jiro
Published: July 2006

The IR spectra for the high-pressure polymorphs of alkaline-earth metasilicates, viz. α-CaSiO3, δ-CaSiO3, α-SrSiO3, δ-SrSiO3, and δ′-SrSiO3, which consist of cyclic anions, (Si3O9)6− or (Si4O12)8− rings, were studied over a range of 1200–400 cm−1. These silicates gave absorption bands in wavenumbers of about 1050–820 cm−1, 750–620 cm−1, and below about 580 cm−1, based on symmetrical and anti-symmetrical stretches of Si–O bonds and Si–O bending modes for tetrahedral SiO4 units, and Ca–O or Sr–O stretches. Among them, the bands characteristic of the silicate anions with ring structure in the SrSiO3 polymorphs were found to shift to lower wavenumber with transformation into the δ′ form. This suggests that the (Si4O12)8− ring in δ′-SrSiO3 is less flexible than the (Si3O9)6− ring in the α or δ form. The experimental result that the quenching temperature of δ′-SrSiO3:Eu2+ phosphor is higher than that of the δ form supports this consideration.
Electroreduction of 4-(2-Thienyl)quinazoline in Acetonitrile
Authors: Devi T Priyamvada , Kalidas Chatty , Venkatachalam Chitoor Sivaramakrishnan
Published: July 2006

The electroreduction of 4-(2-thienyl)quinazoline (4-TQ) in acetonitrile solutions gave a single two-electron well-defined polarographic wave. The well-defined wave was found to be diffusion-controlled and irreversible on the basis of the usual criteria. Based on the controlled-potential electrolysis and cyclic voltammetric experiments, a disproportionation reaction mechanism is suggested for 4-TQ reduction in acetonitrile.
Synthesis of 4,7-Indolequinones by Photoinduced Reaction of Azidoquinones
Authors: Kozuka Tadashi
Published: July 2006

Various azidoquinones were prepared from methyl 3-substituted 2,3-dihydro-5-hydroxy-6-methylbenzofuran-2-carboxylate. Irradiation of these azidoquinones gave methyl 3-substituted 6-methyl-4,7-dioxoindole-2-carboxylates, a model of mitomycin analogs, in a moderate yield.
Syntheses and Properties of Copolymers of Isopropenyl-1,3,5-triazines and Methacrylic Esters
Authors: Seo Toshihiro , Kakurai Toshio
Published: July 2006

Copolymerizations of 2-amino-4-(substituted amino)-6-isopropenyl-1,3,5-triazines (methacryloguanamine) with alkyl methacrylates using redox initiator gave polymers with high molecular weights in satisfactory yields. The monomer reactivity ratios and Q-e values were also determined. Softening and glass transition temperatures rose and specific gravity increased with the increase in the content of triazine units. The copolymers were slightly soluble in nonpolar solvents and readily soluble in polar solvents with a solubility parameter (δ)=11–13. This polymer with aminotriazine groups showed high viscosity in acid solution and can be utillized as polyelectrolyte.
Studies on the Interaction between Mercury(II) Chloride and Copper(I) Halides in Solid State
Authors: Beg Mirza Aijaz , Ahmad Afaq
Published: July 2006

Kinetics and mechanism of HgCl2–CuI and HgCl2–CuBr reactions were studied in solid state. It has been demonstrated that HgCl2 reaches CuI by surface migration and the reaction proceeds through counter diffusion of Cu+ and Hg2+. Both the reactions follow the parabolic rate law and the activation energies are 77.11±3.84 and 51.08±1.29 kJ/mol. While the former is a complex multi-stage reaction, the latter is a simple exchange process.
Direct Preparation of θ-Zirconium Phosphate
Authors: Kijima Tsuyoshi
Published: July 2006

The effects of temperature and Zr concentration in solution on the composition and degree of crystallinity of zirconium phosphate have been examined. Pure θ-zirconium phosphate with an interlayer spacing of 10.4 Å has been prepared by direct precipitation.
14N Nuclear Quadrupole Relaxation in N-Methylpiperidine
Authors: Negita Hisao , Kubo Tsuneo , Maekawa Michio
Published: July 2006

Two crystal modifications of N-methylpiperidine were found by means of the nuclear quadrupole resonance (NQR) of Nitrogen-14. From the temperature dependence of the 14N spin-lattice relaxation times (T1), it is deduced that the α-form has a lower activation energy for the reorientation of the methyl group than the β-form.
Ceroalbolinic Acid, a Common Body Pigment of Three Ceroplastes Scale Insects in Japan. Confirmation of Structure
Authors: Komura Hajime , Mizukawa Kohsei , Minakata Hiroyuki
Published: July 2006

The structure of ceroalbolinic acid, a widely occurring insect pigment, a common body pigment of three Japanese Ceroplastes scale insects, has been confirmed as 2 by 13C-NMR long-range selective proton decoupling (LSPD) experiments on its permethylated derivative 3. Full assignments of skeletal carbons for 3 were also obtained.
A Simple Synthesis of 7-t-Butyl-4-methyl-2,3-dihydrothiepin
Authors: Yamamoto Kagetoshi , Yamazaki Shoko , Murata Ichiro
Published: July 2006

The novel ring expansion reaction developed for the synthesis of 2,6-di-t-butylthiopyrans has been applied to the short path preparation of a dihydrothiepin derivative. Thus, 4-methyl-6-pivaloyl-3,6-dihydro-2H-thiopyran was converted into 7-t-butyl-4-methyl-2,3-dihydrothiepin in excellent yield by using chlorotrimethylsilane-zinc reagent in tetrahydrofuran.
On the Ratio of Zwitterion Form to Uncharged Form of Glycine at Equilibrium in Various Aqueous Media
Authors: Wada Goro , Tamura Eiko , Okina Mitsuko , Nakamura Mariko
Published: July 2006

The ratios of the zwitterion form to the uncharged form of glycine, KD=[NH3+CH2COO−]/[NH2CH2COOH], were determined in mixtures of water with methanol, ethanol, t-butyl alcohol, dimethyl sulfoxide, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and tetrahydrofuran. The value of In KD decreases and, therefore, ΔG298° increases, with the increase in the mole fractions of the organic solvents. The plots of ΔG°  vs. reciprocal of the dielectric constants of the alcoholic mixtures are simply linear indifferent to the kind of alcohols, indicating that this relation obeys the Scatchard equation and that the free energy change of the process of the intramolecular protonation in glycine is controlled mainly by electrostatic interaction, especially by the entropy change associated with the preferential solvation around the charged amino and carboxyl groups.
Nuclear Quadrupole Resonance of Chlorine-35 in Molybdenum(V) and Rhenium(III) Chlorides. Evidence for the Crystal Modifications of MOCl5
Authors: Kume Yoshio , Nakamura Daiyu
Published: July 2006

The 35Cl NQR frequencies were determined for molybdenum(V) and rhenium(III) chlorides at various temperatures. Two crystal modifications, showing two and three 35Cl NQR frequencies, were found for the former compound. The three resonance frequencies observed for the latter compound are attributable to three chemically different chlorine atoms in the crystal.
Two-photon Excitation Spectra of 1-Azabicyclo[2.2.2]octane and Trimethylamine
Authors: Kuno Hitoshi , Kasatani Kazuo , Kawasaki Masahiro , Sato Hiroyasu
Published: July 2006

The two-photon fluorescence excitation spectra of 1-azabicyclo[2.2.2]octane (ABCO) and trimethylamine were measured in the excitation wavelength range of 410–520 nm. The effect of the polarization (linear or circular) indicates that the symmetries of the upper states are \ ildeA1A1, \ ildeB1A1, and \ ildeC1E for ABCO while \ ildeA1A1 and \ ildeB1E for trimethylamine in C3v point group approximation. Rotational envelopes for the sequence structures are calculated forcircularly and linearly polarized light excitation and are in good agreement with experiment.
Vibration-rotation Spectrum of the Coriolis-interacting Band System ν6 and ν3 of Acetonitrile-d3
Authors: Matsuura Hiroatsu , Murata Hiromu
Published: July 2006

The vibration-rotation infrared spectrum of the Coriolis-interacting band system ν6 and ν3 was measured with a resolution of 0.08 cm−1. The analysis of the spectrum gave values, more precise than before, of the parameters for these bands along with the interaction parameters. A close examination of the observed spectrum revealed a weak Fermi resonance between ν6 and ν4+ν8. The parameters determined, in cm−1, include: (ν0)6 1046.659, α6A 0.01550, α6B−0.000443, (ν0)3 1110.46, α3A−0.0078, and α3B 0.00092, where α6B of and α3B af do not involve the contribution of the Coriolis interaction between ν6 and ν3.
The Phase Relation of the Titanium–Sulfur System
Authors: Saeki Masanobu , Onoda Mitsuko
Published: July 2006

The phase relation of the titanium–sulfur system was studied in the range from TiS1.38 through TiS1.96 at 900 °C by the use of the thermobalance method under controlled sulfur pressure. It was found that four phases, (a) Ti2S3 (4H) with a short-range ordering of titanium vacancies, (b) the superstructure of Ti2S3 (4H) due to the ordering of titanium vacancies, (c) Ti2S3 (4H), and (d) TiS2 (2H), exist in this composition range. The Ti5S8 phase of the 12R type reported previously was not detected for any composition.
The Extraction-spectrophotometric Determination of Lead with Bismuthiol II
Authors: Watanabe Kunihiro , Imaeda Yoshitaka , Kawagaki Ky\={o}z\={o}
Published: July 2006

The solvent extraction-spectrophotometric determination of lead(II) with bismuthiol II was conducted in the presence of 1,10-phenanthroline(phen). Lead(II) was quantitatively extracted as ternary complexes into the chloroform phase over the pH range of 3.0–7.0. The composition of the extracted ternary complexes were confirmed to be Pb: bismuthiol II: phen= 1 : 2 : 2 or 1 : 2 : 1, depending on the concentration of bismuthiol II added to the aqueous solution. The absorption maximum of the ternary complex (1 : 2 : 2) in chloroform was found to be at 342 nm, with a molar extinction coefficient of 3.5×104 dm3 mol−1 cm−1. Under optimum conditions, the absorbance follows Beer’s law up to 300 μg of lead in 10 ml of chloroform. The coefficient of the variation was 1.3% for 30 μg of lead. Many elements interfered with the determination of lead(II). However, the interfering ions, with the exception of the indium and bismuth ions, were masked with a potassium cyanide solution. The proposed method was then applied to the determination of lead in standard zinc metals. A good agreement was observed between the results obtained by the proposed method and the standard values of the samples.
The Electron-donor Property of Zirconia
Authors: Esumi Kunio , Meguro Kenjiro
Published: July 2006

The electron-donor property of zirconia was investigated by means of the adsorption of TCNQ. The TCNQ anion radicals were formed as a result of electron transfer to adsorbed TCNQ from the zirconia surface. The radical concentration decreased with an increase in the calcining temperatures, reached a minimum value at 700 °C, and then increased. This behavior can be explained by a change in the electron-donor site number and the strength of the electron-donor site.
The Crystal Structure of p-Iodobenzoic Acid Investigated by X-Ray Powder Diffraction
Authors: Takaki Yoshito , Kurisu Arifumi , Nakata Kazuaki
Published: July 2006

The crystal of the title compound is monoclinic with space group P21/a, a=30.36(3), b=6.04(1), c=4.16(1) Å, β=97.4(1)° and Z=4. The crystal structure was solved from X-ray powder diffractometer data by the packing analysis based on an ellipsoid-model and by the pattern-fitting structure refinement. The final R (profile) value was 0.168. This structure is isostructural with that of p-bromobenzoic acid.
Vinyl Polymerization. 411. Experimental Supports for the Concept of Hard and Soft Hydrophobic Areas and Monomers in the So-called Uncatalyzed Polymerization
Authors: Ouchi Tatsuro , Inaba Masaya , Imoto Minoru
Published: July 2006

We have proposed a concept of hard and soft hydrophobic areas (HA) and monomers. In order to verify such a concept, two series of experiments were carried out. Poly(styrene-alt-disodium maleate) (1) and poly(styrene-altsodium methyl maleate) (2) were used as initiating macromolecules for the copolymerizations of styrene/methyl methacrylate (MMA) and acrylonitrile/MMA. When 1 was used, MMA was more easily polymerized than styrene. Inversely, when 2 was used, styrene was more easily polymerized than MMA. Poly(styrene-co-sodium acrylate) (3) substances with various compositions were used as intiators for the copolymerizations. The produced copolymers of MMA and styrene were found to have a larger content of MMA as the mole ratio of acrylate in 3 became higher. Inversely, the produced copolymers of MMA and acrylonitrile had a larger content of acrylonitrile as the mole ratio of acrylate became higher. Those results could be reasonably explained by the concept of hard and soft hydrophobic areas and monomers.
Studies on 2-Aziridinecarboxylic Acid. VII. Formation of Dehydroamino Acid Peptides via Isomerization of Peptides Containing 2-Aziridinecarboxylic Acid by Tertiary Amines
Authors: Nakajima Kiichiro , Oda Hitomi , Okawa Kenji
Published: July 2006

Peptides containing 1-(α-aminoacyl)-2-aziridinecarboxylic acid were isomerized into the corresponding dehydroamino acid peptides by treatment with the tertiary amines, triethylamine or 1,4-diazabicyclo[2.2.2]octane (Dabco). Dehydrohydantoin derivatives were also prepared by treatment of benzyloxycarbonyl-2-aziridinecarboxylic acid derivatives with tertiary amines.
Noriceane (Tetracyclo[5.3.1.02,6.04,9]undecane) and 3,5-Dehydronoriceane (Pentacyclo[5.3.1.02,6.03,5.04,9]undecane)
Authors: Katsushima Takeo , Yamaguchi Ryohei , Kawanisi Mituyosi
Published: July 2006

Heating a mixture endo, exo- and endo, endo-2,4-dibromohomoadamantanes at 180 °C in hexamethylphosphoric triamide (HMPT) brings about a novel skeletal rearrangement with concomitant dehydrobromination to give tricyclo[5.3.1.04,9]undeca-2,5-diene (5) in 88% yield. Direct photoexcitation of 5 in diethyl ether induces an intramolecular [2+2] cycloaddition to produce 3,5-dehydronoriceane (2). The bicyclo[2.1.0]pentane moiety constrained in the cage structure of 2 shows almost the same 13C–H coupling constants as those of bicyclo[2.1.0]pentane itself. Finally hydrogenation of 2 over PtO2 easily proceeds to afford noriceane, which is named after the structure of iceane.
The Evaluation of the Association Degree of Sodium Counterinos by Complexes between Sodium Dodecyl Sulfate and Bovine Serum Albumin, Mainly on the Basis of a Conductivity Measurement
Authors: Takeda Kunio
Published: July 2006

Bovine serum albumin was titrated conductometrically with sodium dodecyl sulfate (SDS). Plots of the specific conductance versus the SDS concentration revealed four inflections. The association degrees of sodium counterions by the complexes were evaluated from the changes in the increment of the specific conductance of SDS with the complex growth.
Application of Coagulated Ion-exchanger Colorimetry to the Determination of Trace Amounts of Phosphate in Water
Authors: Matsuhisa Kiichi , Ohzeki Kunio , Kambara Tomihito
Published: July 2006

The combined use of finely divided anion and cation exchange resins reported previously was partly modified and applied to the determination of trace amounts of phosphate in some environmental water samples, such as rain, snow, lake water and seawater. Both orthophosphate and total phosphate were determined and satisfactory results were obtained.
Hydrogen Peroxide-catalyzed Ozonation of Refractory Organics. I. Hydroxyl Radical Formation
Authors: Namba Keisuke , Nakayama Shigeki
Published: July 2006

The kinetics of hydrogen peroxidecatalyzed ozonation was studied in aqueous solutions of various lower alcohols containing ethanol as a reference. The relative rates of degradation of alcohols obtained support the initiation of the reaction by hydroxyl radicals formed in the reaction between ozone and hydrogen peroxide.
The structure of the Cyclodextrin Complex. XIV. Crystal Structure of Hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin–Benzaldehyde (1 : 1) Complex
Authors: Harata Kazuaki , Uekama Kaneto , Otagiri Masaki , Hirayama Fumitoshi , Sugiyama Yukio
Published: July 2006

The crystal structure of the hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin (abbreviated to methyl-α-CDx)–benzaldehyde (1:1) complex, C54H96O30·C7H6O, was investigated by the X-ray method. The crystal is monoclinic with the space group P21 and Z=2; the cell dimensions are a=11.604(1), b=23.832(3), c=13.539(1) Å, and β=106.11(1)°. The structure was determined by inspection of a Patterson map and a trial-and-error method combined with the rigid-body least-squares technique, and refined by the block-diagonal least-squares method to the final R-value of 0.10 for 3597 reflections (sinθ⁄λ≤0.49). The methyl-α-CDx molecule is in the shape of a distorted and truncated hexagonal cone. The guest benzaldehyde molecule is fully included within the host cavity. The carbonyl group is located at the center of the cavity, while the phenyl group is located at the baseside of the host cone. Methyl-α-CDx molecules, of which pseudo hexagonal axis is inclined by an angle of 17.0° against the crystallographic a axis, are stacked along the a axis to form a head-to-tail channel-type structure.
A Kinetic Study of Poly(acrylic acid)–Copper(II) Interactions in Aqueous Solutions
Authors: Yamada Ryuichi , Tamura Kiyoshi , Harada Shoji , Yasunaga Tatsuya
Published: July 2006

Concentration-jump kinetic studies of the aqueous poly(acrylic acid)–copper(II) system reveal the presence of a relaxation phenomenon in the time range of 102 ms. Kinetic data under various pH’s and compositions, together with the potentiometric results, indicate that this relaxation effect is due to the following complex-formation reaction:

CuL2+L22−\oversetk2\undersetk−2\ightleftharpoonsCu(L2)22−,

where L22− is a coordination unit consisting of two adjacent carboxylato side groups on the polymer chain. The specific features of the pH dependence of the τ−1 value are discussed in relation to the degree of dissociation of the carboxyl groups. The rate and stability constants of the reaction are determined to be: k2=5.6×103 M−1 s−1 (1 M=1 mol dm−3), k−2=0.7 s−1, and K2 (=k2⁄k−2)=7.9×103, at pH 7.0, I≈0, and 25 °C. The overall complex-formation mechanism, involving the very rapid formation of CuL2, is discussed.