bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoreaction of 1-(1-Cycloalkenyl)-4-phenyl-1-butanone under Neutral and Acidic Conditions
Authors: Tada Masaru , Maeda Tetsuro , Saiki Hiroshi
Published: July 2006

UV irradiation of 1-(1-cycloalkenyl)-4-phenyl-1-butanones gives differing products depending on the reaction conditions, neutral or acidic. In benzene 1-(1-cyclopentenyl)-4-phenyl-1-butanone gives 4-phenylspiro[4,4]-nonan-1-one, formed by the intramolecular abstraction of hydrogen, and 4-cyclopentylidene-4-phenylbutanal, formed by Norrish type I fission of the spiro ketone. 1-(1-Cyclohexenyl)-4-phenyl-1-butanone does not exibit this behavior. Both ketones give the reduction products, 1-cyclopentyl-4-phenyl-1 -butanone and 1-cyclohexyl-4-phenyl-1-butanone, under the action of trifluoroacetic acid, and cyclized products, 7-phenylperhydro-4-indenone and 4-phenylperhydro-1-naphthelenone, under the action of boron trifluoride etherate. The reaction processes under acidic conditions have both an ionic and a free radical nature. The results have lead to the proposition of the mechanism involving electron transfer, proton transfer, and hydrogen abstraction.
A Localized Molecular Orbital Calculation of Chemically Interacting Systems. Interaction between Amines and Carbonyls
Authors: Minato Tsutomu , Fujimoto Hiroshi , Fukui Kenichi
Published: July 2006

The bond interchange in the course of the addition of amine to carbonyl has been studied by means of a localized molecular orbital method with a clear chemical-bond concept, and the mechanism of the addition has been elucidated theoretically. It is ascertained by the present calculation that the charge transfer interaction from the highest occupied molecular orbital of amine to the lowest unoccupied molecular orbital of carbonyl is of importance to form a new nitrogen-carbon bond. Furthermore, the stereospecificity of the nucleophilic addition to a double or triple bond has been studied. When an intermediate is created by the addition of a nucleophile to the unsaturated bond, it is suggested that the intermediate is reactive for the electrophilic attack on the side trans to the new bond formed by the first attack. This is reasoned in terms of the mode of orbital interaction.
Synthesis of Ylide Complexes of Cobalt and the Crystal Structure of [Benzoyl(1-pyridinio)methanide]chlorobis(dimethylglyoximato)cobalt(III) Toluene Solvate
Authors: Saito Taro
Published: July 2006

Bis(dimethylglyoximato)halogenocobalt(III) complexes of benzoyl(1-pyridinio)methanide were synthesized by a new kind of oxidative addition reaction of N-phenacylpyridinium halides to diaquabis(dimethylglyoximato)cobalt(II) in air. The crystal structure of the [benzoyl(1-pyridinio)methanide]chlorobis (dimethylglyoximato) cobalt(III) toluene solvate was solved by single-crystal X-ray diffraction techniques. The crystals are monoclinic (space group P21/c), with cell dimensions of a=11.41(1), b=10.28(1), c=27.50(3) Å, β=116.3(1)°, and Z=4. The final R was 0.068. The ylide ligand coordinates to cobalt through the ylide carbon, with a Co–C distance of 2.07(1) Å, and the chlorine atom is bonded to cobalt with a Co–Cl distance of 2.285(4) Å and with a C(ylide)–Co–Cl bond angle of 175.5(3)°. The dimethylglyoxime ligands and cobalt atom are co-planar to within 0.04 Å.
Acidic Property and Catalytic Activity of Tungsten Oxide
Authors: Hattori Hideshi , Asada Noriyoshi , Tanabe Kozo
Published: July 2006

A maximum activity of tungsten oxide for the isomerization of 1-butene was observed when the catalyst was evacuated at 600 °C, the ratio of cis-2-butene to trans-2-butene being 1.4. The activity was lost by the addition of NH3, but not affected by the addition of CO2 or H2O. The oxidation states of tungsten oxide treated with hydrogen at 550 and 650 °C were WO2.89 and WO2, respectively. The activity of WO2.89 for the double bond isomerization of 1-butene was almost the same as that of WO3 but the activity of WO2 for the double bond and skeletal isomerization of 1-butene and the dehydration of isopropanol was higher than that of WO3 or WO2.89· The coisomerization of cis-2-butene-d0/d8 revealed that the double bond isomerization of butenes proceeds by an intermolecular hydrogen transfer mechanism. When cis-2-butene-d8 was introduced to the catalyst on which cis-2-butene-d0 had been preadsorbed, the reactant and the product containing much of H were obtained, no d0-species being observed. It was concluded that the active sites for the isomerization of butenes are protons of polymerized butene formed by the adsorption on Lewis acid sites of tungsten oxide surface and the isomerization takes place via carbenium ion intermediates.
The Crystal and Molecular Structure of Oxydi(carboxymethyl)bis-(triphenylphosphine)palladium(II), [Pd(C4H4O3)(PPh3)2]
Authors: Zenitani Yukio , Tokunan Haruo , Kai Yasushi , Yasuoka Noritake , Kasai Nobutami
Published: July 2006

The molecular structure of oxydi(carboxymethyl)bis(triphenylphosphine)palladium(II), [Pd(C4H4O3)(PPh3)2] has been determined by means of X-ray diffraction. The crystal belongs to the orthorhombic system, space group P212121, with four formula units in a cell with dimensions of a=16.320(2), b=20.104(2), and c=10.271(2) Å. R=0.058 for 4732 non-zero relfections. The feature of the structure is that the palladium atom is chelated by an acetic anhydride to form a six-membered ring [Pd–C=2.141(13) and 2.124(11) Å], and the palladium atom has a square-planar geometry.
Photochemical Reactions of Aromatic Compunds. XXXI. Exciplex Quenching by Pyridine, Methylated Pyridines, and Methylated Imidazoles and Termolecular Interaction in the Excited Singlet State
Authors: Majima Tetsuro , Pac Chyongjin , Sakurai Hiroshi
Published: July 2006

Pyridine, methylated pyridines, and methylated imidazoles quenched the exciplexes of aromatic nitrile–2,5-dimethylfuran or 2,5-dimethyl-2,4-hexadiene, and the rate constants for the exciplex quenching were obtained. The exciplex quenching by 2-methyl- and 2,6-dimethylpyridines was much less efficient than that by the other quenchers. The exciplex quenching was discussed in terms of the interaction of the n-orbital of the quenchers with the positive charge developed on the electron-donor side of the exciplexes. Curved Stern-Volmer plots were obtained in the quenching of aromatic nitrile fluorescence by 1-methylimidazole and/or 1,2-dimethylimidazole. On the basis of the kinetic results, the mechanism was discussed in terms of a termolecular interaction between excited singlet aromatic nitrile, the methylated imidazole as the π-donor, and the second one as the n-donor.
1,3-Dipolar Cycloadditions to Bicyclic Olefins. V. The Stereo- and Regiochemistry of 1,3-Dipolar Cycloadditions to Several Unsymmetrical Bicyclic Olefins
Authors: Taniguchi Hisaji , Ikeda Toshikazu , Imoto Eiji
Published: July 2006

Each of the 1,3-dipolar cycloadditions of phenylglyoxylonitrile oxide (1), methylglyoxylonitrile oxide (2), benzonitrile oxide (3), and phenyl azide to 2-phenylsulfonyl-2-azabicyclo[3.2.1]octa-3,6-diene (6) occurs only to the C6–C7 double bond, affording two exo regioisomers. Each of the cycloadditions of 1, 2, and 3 to 2-phenylsulfonyl-2-azabicyclo[3.2.1]oct-3-ene (7) gives only one exo adduct. The cycloaddition of C,N-diphenylnitrone to 2-methylenenorbornane (8) gives a mixture of two exo adducts. These results show that the “exo rule” can be extended to the 1,3-dipolar cycloadditions to the bicyclic olefins, 6, 7, and 8. Tentative explanations are offered to account for the exo stereoselectivity and the regio-selectivity in these cycloadditions.
Synthetic Bilayer Membranes with Anionic Head Groups
Authors: Kunitake Toyoki , Okahata Yoshio
Published: July 2006

Anionic amphiphiles which possess two normal alkyl groups as the hydrophobic residue and sulfonate, phosphate or carboxylate groups as the hydrophilic residue were prepared. Most of these compounds aggregate extensively in water to form vesicles and lamellae which are probably formed by the molecular bilayer. These aggregates are quite similar to the lecithin liposome with respect to the restricted molecular motion and cholesterol binding.
Location of the ν1, ν2, ν3, and ν5 Fundamental Vibrations of Ethylene-d4
Authors: Ohashi Nobukimi , Kyogoku Tetsuo , Matsuoka Shin-ichi
Published: July 2006

The QQ branch peaks of the ν1, ν2, and ν3 Raman active bands of ethylene-d4 were located at ν1=2260.8±0.1 cm−1, ν2=1518.3±0.1 cm−1, and ν3=984.4±0.1 cm−1, respectively. The band center of the ν5 band which does not have a QQ branch was determined to be ν5=2315.6±0.3 cm−1 from the analys is in the symmetric top approximation.
Medium Effects on Stereochemistry of Acid-Catalyzed Ethanolysis of trans-2,3-Diphenyloxirane
Authors: Inoue Masashi , Taguchi Yoshio , Sugita Toshio , Ichikawa Katsuhiko
Published: July 2006

The acid catalyzed ethanolysis of trans-2,3-diphenyloxirane was examined in a wide variety of binary ethanolic solvent systems. The reaction proceeded with 26% retention and 74% inversion of configuration in pure ethanol at 50 °C. The dilution of ethanol by hexane or benzene produced almost no change in stereochemistry of the ethanolysis. The addition of acetonitrile, nitromethane, or sulfolane to the ethanolic solution resulted in increased degrees of retention. In binary ethanolic mixtures containing DMSO, DMF, or HMPA, increased ratios of inverted product were obtained. The steric course of the ethanolysis could be controlled from 85% retention–15% inversion (CH3NO2:ethanol=20:2 by volume) to 10% retention–90% inversion (HMPA: ethanol=10:12) by the choice of co-solvent. The results are discussed in terms of the solvation-shell concept.
Asymmetric Synthesis of Alanine by Alkylation of Optically Active N-Alkyl-N-formylaminoacetonitriles
Authors: Harada Kaoru , Tamura Minoru , Suzuki Shinnichiro
Published: July 2006

Optically active N-alkyl-N-formylaminoacetonitriles were prepared and the nitriles were alkylated with methyl iodide. The products were hydrolyzed and hydrogenolyzed to form optically active alanine. The optical yields of alanine ranged from 2 to 18%. The effects of the reaction temperature and of the asymmetric moieties on the optical yields were examined. The optical yields were also determined by the NMR spectra of the resulting diastereomeres.
The Reaction of Ethylbenzene with Methylbenzene–AlCl3–HCl Complex
Authors: Nambu Nobuyoshi , Hamanaka Sawako , Ogawa Masaya
Published: July 2006

Toluene, m-xylene, and mesitylene complexes prepared with AlCl3 and HCl, were separated from the upper hydrocarbon layer and allowed to react with ethylbenzene at 2 and 30 °C. The proton exchange between methylbenzenium ions and ethylbenzene, and the transalkylation of ethylbenzene were investigated by 13C NMR spectroscopy.
Catalysis by Supported Metal Crystallites from Carbonyl Clusters. I. Catalytic Methanol Synthesis under Mild Conditions over Supported Rhodium, Platinum, and Iridium Crystallites Prepared from Rh, Pt, and Ir Carbonyl Cluster Compounds Deposited on ZnO and MgO
Authors: Ichikawa Masaru
Published: July 2006

Methanol synthesis by the catalytic hydrogenation of carbon monoxide proceeded under atmospheric pressure and at 150–250 °C over rhodium, platinum and iridium crystallite catalysts, prepared from well-defined Rh, Pt, and Ir carbonyl cluster compounds highly dispersed on ZnO and MgO. The activity and selectivity of methanol formation depended considerably on the kind of metal carbonyl clusters and metal oxides employed as inorganic carriers. The catalysts prepared by the pyrolysis of smaller Rh, Pt, and Ir carbonyl clusters on ZnO, MgO, CaO, and BeO exhibited a higher selectivity of methanol synthesis. A small amount of ethanol was also produced besides methanol in CO–H2 reaction over the pyrolysed catalysts of Rh carbonyl clusters on MgO, CaO, and BeO. Other metal oxides such as SiO2 gel, γ-Al2O3, SnO2, and WO2 were employed for preparation of the dispersed Rh catalysts from carbonyl clusters, which catalysed mainly formation of methane and higher hydrocarbons with negligible selectivity of the oxygenated products under the reaction conditions.
Kinetic Studies of the Aluminium Acetate Complex Formation Reaction in Aqueous Solutions by the Pressure-Jump Method
Authors: Hiraishi Michinori , Harada Shoji , Yasunaga Tatsuya
Published: July 2006

The pressure-jump method was applied to aqueous solutions of aluminium acetate. Relaxation effects were observed in ms and s regions. Both relaxation times depend a great deal on the pH of solution. They were ascribed to the following complex formation reactions.

(Remark: Graphics omitted.)

Detailed studies on the fast relaxation effect revealed that the hydrolyzed ionic species accelerate the overall reaction. The mechanism of the fast reaction was discussed, the kinetic parameters being obtained.
A Convenient Procedure for Esterification of Carboxylic Acids
Authors: Ono Noboru , Yamada Takashi , Saito Tadashi , Tanaka Kazuhiko , Kaji Aritsune
Published: July 2006

A variety of carboxylic acids including simple acids, sterically hindered acids, thermally unstable acids and N-protected amino acids react with alkyl halides in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in benzene to give esters in good yields. The reaction is simple, affording a general method for esterification of carboxylic acids.
The Intrinsic Viscosity of Poly(4-vinylpyridine) of a Low Molecular Weight
Authors: Hirai Yoshiyuki , Yanagida Taira
Published: July 2006

The intrinsic viscosities of poly(4-vinylpyridine) (\barMn:1.37×103–9.67×104) were measured by use of various solvents. For every solvent, log[η]-log\barMn plots gave lines with a slope of 1/2 in the region of low molecular weights (\barMn≤104). These lines were parallel to one another. This viscosity behavior was interpreted in terms of the influence of solvents on short-range interactions in the polymer chains.
Preparation and Properties of Cu(II) Complexes of N-Picolinoyl-S,S-tetramethylenesulfilimine, N-(Trimethylammonio)picolinamidate, and Related Ylides
Authors: Kise Hideo , Sen\={o} Manabu
Published: July 2006

The reactions of N-picolinoyl-S,S-tetramethylenesulfilimine (PS) and N-(trimethylammonio)picolinamidate (PA) with copper(II) chloride dihydrate in ethanol afforded complexes of the formula CuCl2(Y) and CuCl2(Y)2(Y=PA or PS). The structures of these complexes were examined by spectroscopic and magnetic methods, and it was found that all of them have mononuclear chelate structures. It was concluded that in CuCl2(PS), the ligand is coordinated through two nitrogen atoms, whereas in CuCl2(PS)2, the ligands are coordinated through carbonyl oxygens and nitrogens in pyridine rings. The structures of CuCl2(PA), CuCl2(PA)2, and CuCl(PA) are closely similar to each other and the possibility of coordination through ylidic nitrogens with large ionic contributions to the structures was strongly suggested. Several Cu(II) complexes with monodentate sulfilimines and aminimides were also prepared, and the structural analyses revealed that the nature of the coordination depends largely on the structure of the ylides.
Ultrasonic Absorption Studies of the Nickel(II) Amino Acid Complexes in Aqueous Solutions
Authors: Harada Shoji , Higashi Kazumi , Tamura Kiyoshi , Hiraishi Michinori , Yasunaga Tatsuya
Published: July 2006

The ultrasonic absorption has been measured in aqueous solutions of Ni(II) complexes of glycine, β-alanine, 4-aminobutyric acid, and 6-aminohexanoic acid. The relaxation absorption could not be ascribed to one of the steps of the ordinary step-by-step complex formation mechanism. Kinetic data were obtained as functions of the initial concentrations of Ni(II) and amino acids, the pH, and the temperature. The relaxation absorption was attributed to the formation-breaking equilibrium of an intramolecular hydrogen bond due to the carboxylato group of amino acid coordinated to the Ni(II) ion. The rate constant of the hydrogen bond-breaking process has been obtained. The relationship between the relaxation parameters and the acid dissociation constant of the carboxyl group of the amino acid ligands is discussed with reference to the analogous result for the carboxylato ligands reported previously. Supplementary work is also carried out for Ni(II)-aspartato and glutamato complexes.
Thermolysis of Bis(diarylmethylenecarbamoyl) Peroxides
Authors: Suehiro Tadashi , Matsui Yukio , Inoguchi Yoshio
Published: July 2006

Diacyl peroxides of structure (XC6H4)2C=N–C(=O)OOC(=O)–R (R=(XC6H4)2C=N, X=H (1), X=2-CH3 (3), X=4-CH3; R=4-ClC6H4, X=H (2) have been prepared by the reaction between the corresponding carbamoyl chloride and hydrogen peroxide-urea complex in the presence of pyridine or between the carbamoyl chloride and 4-chloroperbenzoate in anhydrous ether at low temperature. Thermolysis of 1–3 follows first order kinetics. The large rates of thermolysis of 1 and 3 relative to those of bis(diphenylmethyleneacetyl) peroxide have been ascribed to steric compressions of 1 and 3 in the ground state and to the concerted cleavage of three bonds. Stable diphenylmethyleneamino radicals do not substitute in toluene by themselves but they do with the aid of aroyloxy radicals. The iminyl radicals abstract hydrogen from the methyl group of toluene, and the rate constant has been estimated to be 5×102–2×103M−1s−1 at 50 °C.
A Molecular Orbital Treatment of the Electronic Spectra of Linear and Cross Conjugated Systems. Thienyl Phenyl Ketones and N-Thenylideneanilines
Authors: Abu-Eittah R , Hilal R
Published: July 2006

The electronic absorption spectral measurements as well as MO calculations have been conducted on representatives of a cross conjugated system, thienyl phenyl ketones, and a linear conjugated system, N-thenylideneanilines. Results have proved that, although the two systems may be “π”-isoelectronic yet, their electronic spectra differ substantially. The nodal properties of the molecular orbitals of the two systems explain nicely their differences in conjugation. Steric factors play no roll concerning the differences in the spectra of the two systems.
Temperature Effects on CD Spectra of α-Cyclodextrin Complexes with m- and p-Nitrophenol
Authors: Harata Kazuaki
Published: July 2006

The CD spectra of α-cyclodextrin complexes with m- and p-nitrophenol were measured at 10, 30, 50, and 70 °C in aqueous solutions of various α-cyclodextrin concentrations. The CD intensity of both complexes was decreased to 14–61% of the intensity measured at 10 °C with the increase of temperature to 70 °C, but no significant change was observed in the spectral shape. The thermodynamic parameters for the complex formation were determined.
Hydrogen Bond of 4-Amino-5H-[1]benzopyrano[3,4-c]pyridin-5-one Derivatives with Alcohols. II. Theoretical Considerations
Authors: Inuzuka Kozo , Fujimoto Akira
Published: July 2006

In a previous paper the experimental considerations on the hydrogen bonding between benzopyranopyridine derivatives including related compounds (pyridine, coumarin, and aniline) and alcohols were made, and the thermodynamic constants for the formation of the hydrogen-bonded complexes were obtained from UV spectroscopic studies. In this paper the molecular orbital calculation by the CNDO/2 method was conducted to further clarify the experimental results. Several conclusions were drawn from the present calculation: (1) Benzopyranopyridine has an intramolecular hydrogen bond between its amino and carbonyl groups. (2) The hydrogen bond energy of 2-alkyl benzopyranopyridines with alcohol is larger than that of the 1-alkyl compounds. (3) Benzopyranopyridine has four positions for hydrogen bond formation with alcohol, that is, the ring nitrogen atom, the carbonyl group, the ring oxygen atom, and the amino group. The ring nitrogen atom gave rise to the largest hydrogen bond energy among the four positions. Therefore, the corresponding hydrogen-bonded complex plays an important role in the benzopyranopyridine–alcohol system. (4) The hydrogen bond energy depended on the charge density of the atom which gave rise to the hydrogen bond with alcohol. Especially, substitution of the electron donating group such as amino and methyl groups at the position which increases the charge density of the atom giving rise to a hydrogen bond with alcohol increases the hydrogen bond energy.
Studies on Aqueous Solutions of Guanidinium Salts. VIII. Free Energy of Mixing of Guanidinium Bromide and Tetrabutylammonium Bromide in Aqueous Solution at 25 °C
Authors: Miyajima Koichiro , Yoshida Hiromitsu , Nakagaki Masayuki
Published: July 2006

Osmotic and activity coefficients have been determined by the isopiestic comparison method on the water–guanidinium bromide–tetrabutylammonium bromide system at 25 °C. The values of the excess free energy change of mixing and the interaction parameter g0 on Friedman’s formalism were large and negative in magnitude. These results have been discussed in terms of the mixed ion pairing and structural change of water.
Trimethylenediamine Complexes. VI. Kinetic and Equilibrium Studies of Ligand Substitution Reactions of the trans-Aquabis(diamine)sulfito- and trans-Bis(diamine)-hydroxosulfitocobalt(III) Complexes
Authors: Ito Yoshiaki , Terada Akira , Kawaguchi Shinichi
Published: July 2006

Substitution reactions of the trans-CoSO3 (H2O or OH) (en or tn)2 complex with Cl−, Br−, CH3COO−, N3−, NO2−, NCS−, CN−, and SO32− have been studied by the spectrophotometric method. The equilibrium constant of anation KH2OX spans many orders of magnitude, e.g. from 1.24 for bromide to 1.23×107 M−1 for cyanide in the case of the en complex, and is correlated to the electron donor constant En which was defined by Edwards. The kinetics of the substitution reactions is adequately interpreted by virtue of the reversible D mechanism via a five-coordinate intermediate CoSO3(AA)2+. Release of the ligand Xn− from trans-CoSO3(X)(tn)2(1−n)+ proceeds 10–25 times faster than from the corresponding bis(ethylenediamine) complex, and the kinetic ring-size effect is attributed to the larger stability of the en complex as compared with the tn complex at the ground state.
Aminocyclitols. 36. Chlorination and Dechlorination of Aminocyclitol and Inositol Derivatives. Preparation of Dideoxy-and Trideoxystreptamines
Authors: Ogawa Seiichiro , Hongo Yuji , Fujimori Hitoshi , Iwata Keiji , Kasuga Akira , Suami Tetsuo
Published: July 2006

Chlorination of four aminocyclitol and six inositol derivatives with sulfuryl chloride gave the chloro substitution products, which were then dechlorinated by hydrogenolysis with Raney nickel or by treatment with tributyltin(IV) hydride giving the corresponding deoxy compounds. Several useful aminocyclitols, including 2,4-dideoxy- and 2,4,5-trideoxystreptamines, were prepared from 2-deoxystreptamine derivatives by these procedures.
Studies of Peptide Antibiotics. XXXVII. Synthesis of [1,1′,3,3′-l-Alanine]-Gramicidin S
Authors: Takiguchi Hideo , Nishikawa Hiroshi , Ando Setsuko , Izumiya Nobuo
Published: July 2006

An analog containing alanyl residues in place of valyl and leucyl residues in gramicidin S, namely [1,1′,3,3′-l-alanine]-gramicidin S, was synthesized to investigate the influence of the bulky side chains of the amino acid residues for antibacterial activity and conformation. The analog has the small aliphatic side chains of alanyl residues on one side of the ring frame in the gramicidin S-structure. In the experiments of optical rotatory dispersion and circular dichroism, this analog gave curves similar in shape to these of gramicidin S, and thus should have a similar conformation to that of gramicidin S. The analog showed, however, no antibacterial activity. Thus the four methyl side chains of alanyl residues in the analog are not sufficient for the substance to exhibit biological activity.
TiN0.07O1.93 Semiconductor Electrodes for Photoassisted Oxidation of Water
Authors: Hirai Taketsugu , Tari Isao , Yamaura Junichi
Published: July 2006

As a new anode for the photoassisted oxidation of water, the TiN0.07O1.93 semiconductor electrode is proposed. Its photoanodic behavior in 0.1 M Na3PO4 was similar to those of n-type TiO2 electrodes, but the photocur-rent response was a little extended toward the long wavelength region. The electrode stability under the irradiation with ultraviolet light was good.
Kinetic Evidence for the Participation of a Diatomic Oxygen Species in Vapor-Phase Oxidation of Butadiene over Silver Catalyst
Authors: Akimoto Masamichi , Echigoya Etsuro
Published: July 2006

The participation of an adsorbed diatomic oxygen species in the oxidation of butadiene with O2 or N2O to maleic anhydride over silver catalyst was confirmed by the following finding: reaction order with respect to O2 or N2O is 0.83 or 1.95, respectively, whereas that to butadiene is negative.
The Preparation of 6-Nitro-3-acetamidotoluene
Authors: Ono Aoi
Published: July 2006

m-Acetamidotoluene was nitrated with fuming nitric acid in acetic acid or in a mixture of acetic and sulfuric acids at 20 °C, affording 6-nitro-3-acetamidotoluene in 38.6 and 53.7% yields respectively. The melting point of the product was found to be different from that reported in the literature.
Catalytic Activities of La2O3, Y2O3, and CeO2 for Decomposition of 4-Hydroxy-4-methyl-2-pentanone and Isomerization of Butenes
Authors: Fukuda Yasuo , Hattori Hideshi , Tanabe Kozo
Published: July 2006

The decomposition of 4-hydroxy-4-methyl-2-pentanone and the isomerization of 1-butene were carried out over La2O3, Y2O3, and CeO2. The activities for both types of reactions were in the following order; La2O3>Y2O3>CeO2. With La2O3, the change in the activity for the decomposition with the pretreatment temperature of the catalyst correlated well with the change in basicity, the activity and basicity maxima being observed when the catalyst was pretreated at 500 °C. Yttrium sesquioxide showed a maximum activity for the decomposition when pretreated at 700 °C. For the isomerizations of 1-butene and cis-2-butene, La2O3 exhibited activity maxima when pretreated at 700 °C. The cis/trans selectivities from 1-butene were considerably greater than unity, and the trans/1 selectivities from 2-butene were less than unity. The coisomerization of cis-2-butene-d0/d8 revealed that the reaction involved an intramolecular H(or D) transfer. The isotope effects for the formation of 1-butene from cis-2-butene were 4–10, while those for the formation of trans-2-butene were about 1.
The Formation of Ethers from Unsaturated Aliphatic Alcohols in the Presence of Boron Trifluoride Etherate
Authors: Nagai Kimiko , Nakayama Mitsuru , Hayashi Shûichi
Published: July 2006

Unsaturated acyclic alcohols of carbon numbers four and five reacted with boron trifluoride etherate to give eight ethers. Of these ethers, novel acyclic di- and tri-ethers were found in the reaction products of 2-methyl-2-propen-1-ol. Boron trifluoride etherate catalyzes double-bond migration, allylic rearrangement, intermolecular dehydration, and Markownikov addition reactions in unsaturated aliphatic alcohols.
Activation of Carbon Dioxide by Tetraphenylporphinatoaluminium Methoxide. Reaction with Epoxide
Authors: Takeda Norikazu , Inoue Shohei
Published: July 2006

α,β,γ,δ-Tetraphenylporphinatoaluminium methoxide reacts reversibly with carbon dioxide in the presence of 1-methylimidazole, and this carbon dioxide is activated to react with propylene oxide to produce propylene carbonate under atmospheric pressure and at room temperature.
ESR Studies on 2,3,5-Triphenyltetrazolyl and 2,3-(2,2′-Biphenylylene)-5-phenyltetrazolyl Radicals
Authors: Deguchi Yasuo , Kawamura Yoshiko , Takagi Yutaka , Kako Saburo
Published: July 2006

2,3-(2,2′-Biphenylylene)-5-phenyltetrazolium chloride has been prepared. The ESR spectra of 2,3,5-triphenyltetrazolyl and 2,3-(2,2′-biphenylylene)-5-phenyltetrazolyl have been measured and their ESR coupling constants determined.
Syntheses of Rare Earth Orthophosphates
Authors: Hikichi Yasuo , Hukuo Ken-iti , Shiokawa Jiro
Published: July 2006

Rare Earth orthophosphates have been synthesized and examined by X-ray diffraction, DTA and TGA. Six types have been found: a) the monazite type RPO4, b) the xenotime type RPO4, c) the hexagonal form RPO4·0.5H2O, d) the weinschenkite type RPO4·2H2O, e) the orthorhombic form DyPO4·1.5H2O and f) the amorphous phosphate.
Synthesis of cyclo(–l-Leucyl–l-lysyl–glycyl–)2 and Its Hydrolysis by Trypsin
Authors: Kosui Nobuo , Kato Tetsuo , Izumiya Nobuo
Published: July 2006

A protected cyclic hexapeptide, cyclo-(–l-Leu–l-Lys(ε-benzyloxycarbonyl)–Gly–)2 (6) was synthesized by doubling cyclization of the corresponding tripeptide azide. Compound 6 was converted by hydrogenolysis into a cyclic hexapeptide, cyclo(–l-Leu–l-Lys–Gly–)2, which was hydrolyzed by trypsin to a tripeptide, H–Gly–l-Leu–l-Lys–OH.
Charge-transfer Absorption of Complex TCNQ Anion Radical Salts: (Cs+)2(TCNQ)3\ewdot\ewdot and (Morpholinium+)2(TCNQ)3\ewdot\ewdot
Authors: Iida Yôichi
Published: July 2006

The charge-transfer transition between ion radical molecules is known to take place in solid ion radical salts. The present paper describes some spectroscopic features of the charge-transfer absorptions observed in complex anion radical salts of (Cs+)2(TCNQ)3\ewdot\ewdot and (Morpholinium+)2(TCNQ)3\ewdot\ewdot. A one-dimensional Hubbard model consisting of equivalent sites with less than half-occupied orbitals was applied to those systems in order to explain the transition energy and the line shape of the charge-transfer absorptions.
Structure and Absolute Configuration of α-Pompene. II. An X-Ray Analysis of the Mono p-Bromobenzoate of the Diol Derived from α-Pompene
Authors: Nozaki Hiroshi , Matsuo Akihiko , Nakayama Mitsuru , Kushi Yoshihiko , Kamijo Nagao , Hayashi Shûichi
Published: July 2006

The mono p-bromobenzoate of the diol derived from α-pompene has been studied by X-ray crystal structure analysis and determined to be 9-p-bromobenzoxy-8-hydroxy-1,2,6,8-tetramethyltricyclo[5.3.1.02,6]undecane. The crystals are of the orthorhombic space group P212121, a=46.53(2), b=12.20(2), c=7.39(2) Å, Z=8, and hence there are two independent molecules per asymmetric unit. The structure was solved by the heavy-atom methods, and refined by block-diagonal least-squares calculations to a final R value of 0.103 for 2493 observed reflections. The structures of the two independent molecules in the asymmetric unit are quite similar. Both molecules contain a tricyclo[5.3.1.02,6]undecane ring in which three fused rings (cyclohexane, cyclopentane, and cyclopentane) are present. The overall configuration of these three fused rings can be described as a “cis” type. The conformation of the cyclohexane ring is of a chair form, and the two cyclopentane rings exhibit envelope forms. Based on the anomalous X-ray dispersion effect of the bromine atoms, the absolute configuration of the title compound was also determined.
The Substituent Effect. XIII. Solvolysis of 1-(7-Substituted 2-Fluorenyl)ethyl Chlorides and Alkaline Hydrolysis of Ethyl 7-Substituted 2-Fluorenecarboxylates
Authors: Tsuno Yuho , Tairaka Yoshihiko , Sawada Masami , Fujii Takahiro , Yukawa Yasuhide
Published: July 2006

Two sets of rate constants for (i) solvolysis of 1-(7-substituted 2-fluorenyl)ethyl chlorides in both 90 and 80% aqueous acetone and (ii) alkaline hydrolysis of ethyl 7-substituted 2-fluorenecarboxylates in 85% aq EtOH have been determined. Both substituent effects could be correlated excellently with the LArSR relationship; the resulting r+ values (0.82 and 0.47, respectively) were comparable with the r+’s in the corresponding biphenylyl system under the same conditions. The comparison of ρπ+ values clearly indicates a more efficient transmission of the pi-electronic effect in the fluorenyl than in the biphenylyl ststem (1:0.75). This can be attributed to a factor of twisting in the latter pi-system. The attenuation of the transmission of the Pi effect was found to be characteristic of the intervening pi-systems independent of reactions: 1.00(4-X-1-phenyl), 0.55(6-X-2-naphthyl), 0.35(7-X-2-fluorenyl), and 0.25(4′-X-4-biphenylyl).
Kinetic Studies on the Lime Sulfurated Solution (Calcium Polysulfide) Process for Removal of Heavy Metals from Wastewater
Authors: Yahikozawa Kiyochika , Aratani Toshiro , Ito Ryuzo , Sudo Takataro , Yano Takeo
Published: July 2006

A new process has been developed for wastewater purification, utilizing “Lime Sulfurated Solution” as a coagulant. Calcium polysulfide, the main component of this solution, decomposes in water on contact with a gas (atmospheric air or CO2 gas) and reacts with heavy metals. The heavy metals are removed as practically insoluble precipitates. The kinetics of this process were studied in a batch stirred tank vessel to obtain the fundamental data needed for development of a commercial continuous process. The findings are as follows: (1) Processing of bivalent metals Hg2+, Cd2+, Zn2+, Pb2+, and Cu2+ are completed in a few minutes to achieve the water quality standards in Japan. (2) Cr3+ is flocculated as Cr(OH)3 by the strong alkaline base of CaSx solution. It takes about 60 minutes for the precipitation with CO2 blowing, and 30 min with aeration. Cr(VI) is quickly reduced to Cr3+ and removed as Cr(OH)3. (3) A simulated wastewater simultaneously contaminated with 6 kinds of heavy metals can be brought well within the standards within 20 min of processing time.
The Solvent Extraction of Thallium(I) as a Dibenzo-18-crown-6 Complex with the Picrate Ion
Authors: Sekine Tatsuya , Wakabayashi Hiroji , Hasegawa Yuko
Published: July 2006

The solvent extraction of thallium(I) with dibenzo-18-crown-6 (DBC) as the picrate into chloroform and benzene was measured at 25 °C. The extraction was nearly the same as that of potassium(I) and much better than rubidium(I); this tendency was mainly attributed to the difference in the stability of the DBC complexes in the aqueous phase. Thallium(III) was extracted only poorly.
The Derivation of a Brominated Algal Component from Myrcene
Authors: Yoshihara Kazuo , Hirose Yoshio
Published: July 2006

The supposed structure, 5-bromo-4,4-dimethyl-2-vinyl-1-cyclohexene, for a brominated monoterpene from Desmia (Chondrococuus) hornemanni was derived from myrcene through a one-step reaction, and the structure was confirmed.
Solvent Extraction Equilibria of Acids. VI. The Extraction of Several Mono- and Dicarboxylic Acids with Trioctylphosphine Oxide in Hexane
Authors: Niitsu Masaru , Sekine Tatsuya
Published: July 2006

The solvent extraction equilibria of acetic, propionic, and butyric acid and mono-, di-, and trichloroacetic acid (HA), as well as those of oxalic, malonic, succinic, glutaric, and adipic acid (H2A), have been determined in liquid–liquid systems of hexane containing none or a certain amount of trioctylphosphine oxide (E) and an aqueous 1 mol dm3 chloride solution at 25°C. The constants, Kd=[HA]org/[HA], Kdim=[(HA)2]org/[HA]org2, Kex1′=[HAE]org/[HA][E]org, Kex2′=[H2AE2]org/[H2A][E]org2, and β1(org)=[HAE]org/[HA]org[E]org2, have then been determined from the data. It was found that, among the three fatty acids, the value of Kex1′ was higher as the chain length increased, but the values of β1(org) were nearly all the same, while among the chloroacetic acids they were higher as the number of chloride atom increased. The extraction of the dicarboxylic acids with E was not very different, although the number of the –CH2– between the two carboxyl groups changed from zero to four.
Photochemical Oxidation of Benzene, Toluene, and Ethylbenzene Initiated by OH Radicals in the Gas Phase
Authors: Hoshino Mikio , Akimoto Hajime , Okuda Michio
Published: July 2006

Photochemical oxidation of benzene, toluene, and ethylbenzene initiated by OH radicals in the presence of NO and NO2 was studied in the air by using a 67 dm3 reaction chamber made of Pyrex glass. OH radicals were produced by photochemical decomposition of nitrous acid, the products being phenol and nitrobenzene for benzene; cresols, benzaldehyde, m- and p-nitrotoluenes, and benzyl nitrate for toluene; ethylphenols, benzaldehyde, acetophenone, and m- and p-nitroethylbenzene for ethylbenzene. The reaction mechanisms are proposed based on the addition of OH radicals to aromatic rings and the hydrogen abstraction of OH radicals from alkyl groups.
Syntheses of Unsymmetrical Sulfides and Bis(alkylthio)methanes from Diphenylphosphinodithioate Esters
Authors: Goda Koshiro , Hanafusa Fumito , Inamoto Naoki
Published: July 2006

Unsymmetrical sulfides were prepared by the reactions of diphenylphosphinodithioate esters with organolithiums in tetrahydrofuran (THF) at −78 °C or at room temperature in fairly good or excellent yields. Similarly, methylene bis(diphenylphosphinodithioate) gave bis(alkylthio)methanes by reactions with organolithiums in good yields. The use of bad-smelling thiols is avoided and the phosphorus part can be recycled after sulfurization and esterification. Allyl diphenylphosphinodithioate gave allylbenzene via  SN2(C) reaction upon treatment with phenylmagnesium bromide in refluxing THF.
Chemical Studies on Tuberactinomycin. XIV. Novel Synthesis of Dl-Capreomycidine
Authors: Wakamiya Tateaki , Mizuno Katsutoshi , Ukita Tatsuzo , Teshima Tadashi , Shiba Tetsuo
Published: July 2006

Cyclic guanidino amino acid, capreomycidine, is a component of antituberculous peptides, capreomycin and tuberactinomycin N and O. Its epimer was also found in protease inhibitors, chymostatin and elastatinal. A new synthetic approach to Dl-capreomycidine via β-hydroxyornithine was studied for the purpose of total synthesis of capreomycidine and epicapreomycidine of natural forms or its hydroxy derivative, tuberactidine.
Biosynthesis of Aloenin in Aloe arborescens var. natalensis
Authors: Suga Takayuki , Hirata Toshifumi
Published: July 2006

The 14C- and 3H-labeling patterns in aloenin biosynthesized by uptake of acetate-1-14C, malonate-2-14C, phenylalanine-1-14C and -3-14C, methionine-methyl-14C, and glucose-3-3H to Aloe arborescens var. natalensis demonstrated that the carbon skeleton of aloenin is arisen via a biological polyketide by the acetate-malonate pathway and the O-methyl group originates from methionine. Further, feeding experiments of 3H/14C-doubly labeled 4-methoxy-6-(2,4-dihydroxy-6-methylphenyl)-2-pyrone and 5-(2-β-d-glucopyranosyloxy-4-hydroxy-6-methylphenyl)-3,5-dioxopentanoic acid in the Aloe plant revealed that an immediate intermediate is the pyrone derivative and not the dioxopentanoic acid derivative. Aloenin was demonstrated to be biosynthesized in such a way that the first formation of the pyrone by cyclization of the biological polyketide and then O-methylation of the cyclized intermediate is followed by introduction of a glucose molecule into the pyrone derivative.
New Methods for the Preparation of 3-Substituted Furans
Authors: Inomata Katsuhiko , Aoyama Shin-ichi , Kotake Hiroshi
Published: July 2006

It was found that ethyl 4,4-dimethoxy-2-(phenylthio)butyrate and 3-tosylpropanal ethylene acetal are useful starting materials for the preparation of 3-substituted furans. Several 3-substituted furans, including dendrolasin [3-(4,8-dimethyl-3,7-nonadienyl)-furan], were prepared by the reaction of these compounds with alkyl halides in good yields.
Critical Micelle Concentration Reduction of Aqueous Sodium Dodecyl Sulfate Solutions upon the Addition of Alcohols
Authors: Hayase Kohji , Hayano Shigeo
Published: July 2006

Linear relations were found between the critical micelle concentration (CMC) reduction and the carbon number of the alcohols added both at 313.15 K and 328.15 K. The slopes of the CMC reduction against the carbon number of the alcohols are almost the same at 298.15, 313.15, and 328.15 K.
A-Substituted 5β-Steroids. IX. Preparation of 5β-Cholest-1-ene and 2-ene from 2β-Bromo-5β-cholestan-3-one
Authors: Abe Kanji , Satoh J Yasuo
Published: July 2006

5β-Cholest-1-ene has been prepared from 2β-bromo-5β-chloestan-3-one. An alternative route to 5β-cholest-2-ene has also been developed by use of bromoketone. These olefins are less stable, being oxidized gradually by air to 5β-cholest-1-en-3-one at room temperature.
A Quinone and a Phenol from a Myrsinaceae Plant
Authors: Kusumi Takenori , Kakisawa Hiroshi , Chen Yuh-Pan , Lyn Jing-Ing , Hsu Hong-Yen
Published: July 2006

Ardisianone and ardisianol isolated from Ardisia quinquegona Blume were determined to be 2-(2-acetoxypentadecyl)-6-methoxy-1,4-benzoquinone and 4-acetoxy-2-(2-acetoxypentadecyl)-6-methoxyphenol, respectively.
Intramolecular Hydrogen Bond between Hydroxyl Group and π-Base in 2-Hydroxybiphenyl
Authors: Ioki Yoshikazu , Kawana Hiroko , Nishimoto Kichisuke
Published: July 2006

In order to clarify the nature of the intramolecular hydrogen bond between the hydroxyl group and the π-electron system in 2-hydroxybiphenyl, MO calculation based on the CNDO/2 MO method has been carried out. The total electronic energy of the molecule has been divided into one- and two-atomic terms. It was found that the resonance term mainly contributes to the intramolecular hydrogen bond formation. Contribution of other terms is discussed.
A Rate Study on the Oxidative Addition Reactions of Iodine toward Tetrakis(2,4,6-trimethylphenyl and t-butyl isocyanide)rhodium(I) Perchlorates
Authors: Kuwae Ryosho , Tanaka Toshio
Published: July 2006

The reaction of [RhL4]ClO4 (L=2,4,6-Me3C6H2NC and t-BuNC) with an equimolar amount of iodine yields a trans adduct, [RhI2L4]ClO4. The rate of this reaction in acetonitrile was measured employing a stopped-flow technique under pseudo-first-order conditions with excess iodine. The result indicates that the reaction proceeds via an intermediate which is presumably assigned to cis-[RhI2L4]ClO4, followed by intramolecular isomerization to the trans adduct.
A Semi-empirical MO Study of Radical-induced Decomposition of Dibenzoyl Peroxide. The Charge-transfer Character and Reaction Mechanism
Authors: Kikuchi Osamu , Suzuki Keizo , Tokumaru Katsumi
Published: July 2006

Radical-induced decomposition reactions of diacyl peroxides were investigated on the basis of the electronic structure of the peroxide-radical systems which were calculated using an approximate restricted open-shell SCF MO method in the MINDO/3 approximation, and on the basis of configuration analysis of the transition state of the reaction. For the transition state, (1) the change in peroxy O–O bond length is expected to be small, (2) the odd-electron density on the leaving group of the SH2 displacement is expected to be very small, although appreciable odd-electron delocalization from the radical to the peroxide was observed, (3) the charge-transfer (CT) interactions which correspond to electron transfer from the radical to the peroxide was found to be important in the transition state. The trends observed in the orbital energies of the LUMO of substituted dibenzoyl peroxides and in the CT character of the transition state, which involves the singly-occupied MO of the radical and the 2pσ* MO of the peroxide, agree well with the experimental facts, and strongly support a previous postulate that an important role is played by the 2pσ* MO of the peroxy O–O group in the reaction.
Substituent Effects on 6-Substituted 3-Hydroxy-1-methyl-4-pyridones
Authors: Imafuku Kimiaki , Takahashi Kumio , Matsumura Hisashi
Published: July 2006

Acid dissociation constants and UV and NMR spectra of a series of 6-substituted 3-hydroxy-1-methyl-4-pyridones have been measured. The acid dissociation constants have been analyzed in terms of the Hammett equation to give linear relationships, with ρ=1.16 for the conjugate acids and ρ=1.06 for the neutral compounds. Halochromism in the UV spectra gave the equation: Δ\ ildeν=689 pKa−9399, and the Hammett plots of the chemical shifts of the 2-H, 5-H, and CH3 protons gave linear relationships, with ρ=1.78, 2.56, and 1.39, respectively.
Pseudo-sugars. 4. A Facile Synthesis of Dl-Validamine and Its Derivative
Authors: Ogawa Seiichiro , Nakamoto Koji , Takahara Masaaki , Tanno Yoshio , Chida Noritaka , Suami Tetsuo
Published: July 2006

Penta-N,O-acetyl-Dl-validamine was prepared from readily available endo-2, exo-3-diacetoxy-endo-6-acetoxymethyl-7-oxabicyclo[2.2.1]heptane in three steps in an overall yield of 36%.
Carbon-Carbon Bond Formation by Use of Chloroiodomethane as a C1 Unit. I. Formation of Chloromethyltriphenylphosphonium Iodide, and Its Application for the Wittig Chloromethylenation of Aldehydes and Ketones
Authors: Miyano Sotaro , Izumi Yu , Fujii Katsuo , Ohno Yutaka , Hashimoto Harukichi
Published: July 2006

Chloromethyltriphenylphosphonium iodide has been prepared by the reaction of chloroiodomethane with triphenylphosphine. Upon treatment with potassium t-butoxide in t-butyl alcohol, the phosphonium iodide was converted into chloromethylenetriphenylphosphorane; this in turn was used for the Wittig reaction of aldehydes and ketones into the corresponding chloroolefins of the type RCH=CHCl and RR′C=CHCl in good to moderate yields. The configurations of these chloroolefins were assigned on the basis of NMR spectral studies. Direct conversion of benzaldehyde into phenylacetylene was also achieved using the phosphonium salt and excess potassium t-butoxide.
The Vibrational Spectra and Rotational Isomerism of 3-Butenylsilane
Authors: Taga Keijiro , Ohno Keiichi , Murata Hiromu
Published: July 2006

The infrared and Raman spectra of 3-butenylsilane, CH2=CHCH2CH2SiH3 (and –SiD3), were measured for the gaseous, liquid, and solid states. The fundamental vibrations were assigned, and the normal vibrations were calculated in relation to the rotational isomerism. The calculations indicated that the cis-trans (CT), skew-trans (ST), and skew-gauche (SG and SG′) forms coexist in the gaseous and liquid states, while the CT form only persists in the solid state. From the temperature variation in the Raman intensities, the stability of the molecular conformations was found to be in this order: CT\gtrsimST>SG′>SG in the liquid state, indicating that an appreciable interaction between the silicon atom and the C=C bond, such as in the case of allylsilane, is not present for 3-butenylsilane.
Transannular Interaction in the Excited Triplet States of [2.2]Paracyclophane and Related Compounds
Authors: Ishikawa Shun-ichi , Nakamura Junko , Iwata Suehiro , Sumitani Minoru , Nagakura Saburo , Sakata Yoshiteru , Misumi Soichi
Published: July 2006

The triplet-triplet absorption spectra of [2.2]paracyclophane and related cyclophanes (naphthalenophane, pyrenophane, and anthracenophane) were measured. Cyclophanes in which two component subunits fully overlap, show new bands together with monomer-like bands. The electronic structures of triplet states of these cyclophanes were studied theoretically by the “molecules in molecule” method, special attention being paid to the correlations of the electronic structures of cyclophanes with those of corresponding monomers and also to the dependences of the charge transfer interaction upon the overlapping between the component subunits and upon the molecular size.
On the Phase Transitions in Hydrazinium(2+) Sulfate
Authors: Okamoto Takeo , Nakamura Nobuo , Chihara Hideaki
Published: July 2006

The existence of a “diffuse” phase transition below room temperature has been confirmed in N2H6SO4 crystal by powder X-ray and DTA experiments. The transition temperature is very sensitive to the grain size. This size effect was discussed on the basis of the thermodynamic nucleation theory taking into account the interfacial energy between the high and the low temperature phases. The diffuse nature of the transition was interpreted by a theory proposed by Tobolsky et al. The spin-lattice relaxation times of 1H were redetermined and the nature of the cationic motion in each phase was discussed.
The Correlation of Basicity and Equilibrium Constants Evaluated from Lanthanoid-induced Shifts in the Eu(fod)3-p-Substituted Aniline Systems
Authors: Hirayama Masatoshi , Owada Masashiro
Published: July 2006

An approximate linear correlation has been found between the basicity of substrate (pKa) and the logarithm of the equilibrium constant K1 for 1:1 adducts evaluated from the least squares analysis of lanthanoid-induced shifts (LIS) for the systems containing Eu(fod)3 and a series of p-substituted anilines in CDCl3. In contrast, both the observed S-values and intrinsic shifts have shown no simple correlation to pKa’s of substrates.