bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Preparations of Metal Complexes. V. The Preparations of Cholatoamminecomplexes of Cobalt(III) and Chromium(III)
Authors: Nakahara Masayoshi , Urushiyama Akio , Satoh Yasuo , Kondo Yukio 
Published: July 2006

Abstract
The mono-, di- and tricholatocobalt(III) and chromium(III) complexes and cobalt complex cholates, including the following new compounds, have been prepared: [Co chol (NH3)5] X2 (X=chol, Cl), [M chol2 en2]Cl (M=Co, Cr), [Co chol3 (NH3)3] and [Co en3]chol3. The absorption spectra of these complexes in the visible, ultraviolet, and infrared regions have been measured and compared with those of the corresponding acetato- or acido-complexes.
Photoinduced Reactions. XLII. Homolytic Expulsion of 4-Substituent in the Photochemical Reaction of 2,5-Cyclohexadienones
Authors: Ogura Katsuyuki , Matsuura Teruo 
Published: July 2006

Abstract
Irradiation of 2,4,6-tri-t-butyl-4-bromo-2,5-cyclohexadienone (X) in various solvents yielded 2,4,6-tri-t-butylphenol (XIII) in high yields. It was shown that 2,4,6-tri-t-butylphenoxy radical (XII) was formed as an intermediate and that the light of shorter wavelengths than 450 mμ accelerated the hydrogen abstraction of XII. The rate of the photochemical decomposition of X decreased in the order: n-hexane, N,N-dimethylformamide and acetic acid. This and the sensitized reaction suggest that the formation of XII from X may result from the n-π* triplet state of X. On the other hand, irradiation of 2,4,6-tri-t-butyl-4-nitro-2,5-cyclohexadienone (XI) afforded 2,6-di-t-butyl-p-quinone (XV) and 2,4,6-tri-t-butylphenol (XIII), indicating a homolytic cleavage of the C–NO2 bond.
Studies of the Reissert-Kaufmann-type Reaction of 4-Nitropyridine N-Oxide and Its Homologues
Authors: Matsumura Eizo , Ariga Masahiro , Ohfuji Takahiko 
Published: July 2006

Abstract
The Reissert-Kaufmann-type reaction of substituted N-methoxy-4-nitropyridinium methylsulfates gave the corresponding 2-cyano-4-nitropyridines in satisfactory yields. When 3-methyl-4-nitropyridine N-oxide was used as the starting material, a cyano group was introduced not into the 6-position, but into the 2-position. This preference may be explained by proposing a hyperconjugation effect of the 3-methyl group. The resulting nitriles were quantitatively hydrolyzed to the corresponding 4-nitropicolinic acids. These reactions provided a new route for the preparation of nitropyridinecarboxylic acids from pyridine homologues. Further, some nucleophilic substitution reactions of the products were carried out.
Radiative Lifetime Measurements of N2(C3IIu), NH(A3II) and NH(C1II)
Authors: Sawada Tsuguo , Kamada Hitoshi 
Published: July 2006

Abstract
The radiative lifetimes of N2(C3IIu), NH(A3II), and NH(C1II) states were measured by the use of the time-sampling technique. The excited molecules were produced by the electron bombardment of N2 and NH3 gas. The lifetimes obtained in this experiment for N2(C3πII), NH(A3II), and NH(C1II) were (4.8±0.3)×10−8 sec, (4.1±0.2)×10−7 sec, and (4.3±0.2)×10−7 sec respectively. The oscillator strengths of the respective transitions were also calculated.
Measurement of Negative Ions Formed by Electron Impact. VII. Negative Ion Mass Spectra from Alkyl Cyanides
Authors: Tsuda Satoru , Yokohata Akira , Umaba Toshikatsu 
Published: July 2006

Abstract
The negative ion mass spectra from alkyl (methyl, ethyl, n- and iso-propyl) cyanides with electron energies of 80 eV, 40 eV and 9.5 eV were measured by a Hitachi RMU-6D mass spectrometer with emphasis on the relative abundance of negative ions to positive ions with electron energies of 80 eV, 40 eV and 15 eV. In every sample, the electron impacts with 80 eV and 40 eV gave almost the same distribution of m⁄e for negative ion mass spectra. Then, the peak of m⁄e 26(CN ) ions was the most intense and also the relatively strong peak of 25(C2H−) ions was found through all samples. On the other hand, the formations of 38(C2N−), 39(CHCN−) and 41(CH3CN−) ions from methyl cyanide, of 50 (C3N−) ions from ethyl cyanide, n- and iso-propyl cyanides, of 40(CH2CN−) ion from n-propyl cyanide were characteristic of each sample. The ratio of the yield of negative ions to positive ions was respectively of the order of ∼104 for CH3CN+/CN− (CH3CN), C2H4+/CN− (C2H5CN), C3H5+/CN− (n-C3H7CN) and C3H6+/CN− (iso-C3H7CN) at 80 eV and 40 eV electron energies. At 9.5 eV, m⁄e 26 (CN−) ions predominated over other negative ions for all the samples and a much larger peak of 40 (CH2CN−) ions in n-C3H7CN than in iso-C3H7CN was also observed. Then, we got the values of 19∼65 for CH3CN+/CN−, C2H4+/CN−, C3H5+/CN− and C3H6+/CN− (15 eV for positive ions). This work also gave linear relationship of the yield of each negative ion to the pressure in the range used for an usual chemical analysis.
The Stability of Fused Rings in Metal Chelates. VII. Copper(II) Complexes of Schiff Bases Derived from 2-Acetylpyridine or Pyridine-2-aldehyde and Dipeptides Containing Glycine, β-Alanine and/or α-Aminoisobutyric Acid
Authors: Nakao Yasuo , Ishibashi Hiroyuki , Nakahara Akitsugu 
Published: July 2006

Abstract
Eight new copper(II) complexes of SchifF bases derived from 2-acetylpyridine or pyridine-2-aldehyde and dipeptides containing glycine, β-alanine and/or α-aminoisobutyric acid have been prepared, and their relative stability was discussed on the basis of numerical data obtained by spectrophotometric, polarographic and other measurements. As a result, it was found that the stability of fused-ring systems decreases in the order 5-5-6-\simeq5-6-5-&gt;5-5-5-&gt;5-6-6-system (the first number represents the number of ring members containing pyridine derivatives and the second and third numbers represent those of ring members containing dipeptide moieties). The conclusion proposed previously that SchifF base chelates of aldehydes are generally less stable than those of corresponding ketones, has been proved to be valid also for the copper(II) chelates. It was found that transamination reactions take place in the copper(II) chelates of Schiff bases with pyridine-2-aldehyde and glycylglycine or glycyl-β-alanine.
Aromatic Metalation Reactions by Palladium(II) and Platinum(II) on Aromatic Aldoximes and Ketoximes
Authors: Onoue Hiroshi , Minami Kyoji , Nakagawa Kunio 
Published: July 2006

Abstract
Ortho metalation by palladium(II) was observed in the reaction of lithium tetrachloropalladate(II) with various aromatic aldoximes and ketoximes in methanol in the presence of sodium acetate. The obtained chloro-bridged complexes(7) possessed both ortho-attached palladiumcarbon σ-bonding and palladium-nitrogen coordinate bonding to oximes. Reactions of O-acyl and O-methyl oximes with lithium tetrachloropalladate(II) were also carried out. An ortho metalation was observed in the former case, but dichlorobis(O-methyl oxime)palladium(II) type complexes containing no palladium-carbon σ-bonds were predominantly formed in the latter case. The bridge-splitting reaction of chloro-bridged complexes with triphenylphosphine and the metathetic reaction with sodium bromide in acetone were carried out. In the case of potassium tetrachloroplatinate(II), an ortho metalation reaction was observed giving the complexes(10) but chloro-bridged complexes could not be isolated.
A Study of the Partial Catalytic Oxidation of Hydrocarbons. V. The Effect of Phosphorus Addition to the Vanadium Catalyst on the Oxidation of Butene, Butadiene, and Furan
Authors: Ai Mamoru 
Published: July 2006

Abstract
In the present investigation, the vapor-phase partial oxidation of cis-2-butene, butadiene, and furan was carried out over V2O5 and V2O5-P2O5, (1 : 1.6 atomic ratio), with various contact times, at 350°C, and at the concentration of 0.6–1.6% in air, in order to elucidate the effect of phosphorus addition to V2O5, on the selectivity and mechanism of butene oxidation. Oxidation activity decreased remarkably with an increase in the phosphorus content. In the presence of phosphorus (P/V=1.6), selectivity for the C4H8→C4H6 step and C4H6→C4H4O step were considerably increased, from 46 to 88 and from 72 to 93 mol% respectively, while selectivity for the C4H4O→maleic anhydride (MA) step fell from 60 to 50 mol%, due to the increase in polymer formation. From the results, it was concluded that V2O5 and V2O5-P2O5 catalysts show similar oxidation activity with regard to butene, butadiene, and furan, and that the quantities of the intermediate products are fairly much affected by the activity of the catalyst as well as by the difference in reactivity between the starting material and the intermediate over the catalyst.
Synthesis of Poly-malonylpolymethylenes
Authors: Matsui Kiyotada , Murotani Sadaichi , Nojiri Tetsuro , Motoi Masatoshi 
Published: July 2006

Abstract
Treatment of acetic anhydride with aliphatic dibasic acid chloride in the presence of 3 equivalents of aluminum chloride in nitrobenzene at 50°C afforded a polymer with the structure assigned to poly-malonylpolymethylene, R–[(CH2)m–COCH2CO]n–(CH2)m–R, (R=–COOH and/or –COCH3, n=8–16). Polymalonyl-heptamethylene, -hexamethylene and -pentamethylene were prepared and their properties were recorded. The product obtained by the reaction of acetic anhydride with adipoyl chloride seems to have a few cross-linkings in its structure.
Structure and Reactivity of α,β-Unsaturated Ethers. XII. Cationic Copolymerization of Ring-Substituted Styryl Ethyl Ethers
Authors: Okuyama Tadashi , Asami Nobuhiro , Fueno Takayuki 
Published: July 2006

Abstract
Several ring-substituted derivatives of cis- and trans-styryl ethyl ethers were copolymerized with the unsubstituted trans ether in methylene chloride at −70°C with the use of boron trifluoride etherate as a catalyst. The ring substituents investigated include p-CH3O, p-CH3, m-CH3, p-Cl, and m-Cl. It was found that the effects of substituents on the polymerizability obey the Hammett ρσ relationship with reaction constants ρ=−2.4 and −2.0 for cis and trans isomers, respectively. The structure of the transition state of the cationic polymeization was discussed.
Crystal and Molecular Structure of Di-μ-chloro-bis(π-1-ethoxycarbonyl-2-hydroxyallyl)dipalladium(II)
Authors: Oda Kunio , Yasuoka Noritake , Ueki Tatzuo , Kasai Nobutami , Kakudo Masao 
Published: July 2006

Abstract
The crystal and molecular structures of di-μ-chloro-bis-(π- 1-ethoxycarbonyl-2-hydroxyallyl)-dipalladium, (C6H9O3PdCl)2 have been determined from the three-dimensional data. The crystals are triclinic; space group Pl; with one dimeric molecule per unit-cell; a=4.80, b=10.31, c=10.64 Å, α=117.4, β=102.3, and γ=84.1°. The final discrepancy index is 14.0% for 1208 reflections. The two palladium atoms are joined by two chlorine bridges to form a square planar arrangement. The molecule possesses a center of symmetry which coincides with a crystallographic center of symmetry in the crystal; the overall coordination scheme of the palladium atom is similar to that established for the π-allyl palladium chloride dimer. The dihedral angle between the plane of four atoms [Pd, Pd′, Cl, and Cl′] and the π-allyl plane is 108. There are intermolecular hydrogen-bonds between the enolic hydroxyl group of one molecule and the carbonyl-group of the other molecule related by the center of symmetry.
Mechanism of Hydrogenolysis. I. Effect of Methyl Substituent on the Demethylation Rate of Polymethylbenzenes
Authors: Amano Akira , Uchiyama Masao , Sato Yoshiki , Tominaga Hiroo , Arai Hiromichi , Kunugi Taiseki 
Published: July 2006

Abstract
Rates of demethylation of six different polymethylbenzenes have been measured, at 702°C and residence times ranging from 0.5 to 6.0 sec in the presence of five-fold in excess hydrogen, by using toluene as an internal reference. The rates per one equivalent methyl group were: 1.08 for p-xylene, 1.73 for o-xylene, 1.26 for 4-position of 1,2,4-trimethylbenzene, 1.87 for 2-position of 1,2,4-trimethylbenzene, 1.85 for 1-position of 1,2,4-trimethylbenzene, 1.20 for 1,3,5-trimethylbenzene, 2.22 for 1-positionof 1,2,3-trimethylbenzene, 3.25 for 2-position of 1,2,3-trimethylbenzene, 1.5 for 5-position of 1,2,3,5-tetramethylbenzene, 2.1 for 1-position of 1,2,3,5-tetramethylbenzene, and 2.8 for 2-position of 1,2,3,5-tetramethylabenzene. all the figures being expressed against the standard value of 1.00 for toluene. The observed accelerating effect of neighboring methyl groups on the demethylation rates of crowded reactant molecules has been correlated with modified superdelocalizability in z direction for radical aromatic substitution. The latter values calculated by the extended Hückel molecular orbital method were: 0.4070, 0.4116, 0.4908, 0.4169, 0.4124, 0.4116, 0.4131, 0.4133, 0.4148, 0.4204, 0.4120, and 0.4029 (toluene) in the order given above. The general parallelism between the observed and the theoretical values may be taken as a support not only of the extention of the concept of superdelocalizability to radical aromatic substitution, but also of our mechanistic interpretation on the key reaction of hydrogenolyses.
Microwave Spectrum of Ethylene Episulfone
Authors: Nakano Yuji , Saito Shuji , Morino Yonezo 
Published: July 2006

Abstract
Microwave spectra of normal, 13C-, and 34S-isotopic species of ethylene episulfone have been investigated. Analysis of the spectra shows that the molecule has the C2V symmetry. The structural parameters obtained from the spectral data for the normal and 13C-ethylene episulfone are: r(C–C)=1.590±0.011 Å, r(C–S)=1.731±0.006 Å, r(S–O)=1.439±0.006 Å, ∠CSC=54°40′±15′, and ∠OSO=121°26′±30′, on the assumption that the C–H distances and the ∠HCH and ∠H2CC angles are the same as those of ethylene sulfide. Stark-effect measurements have yielded a value of 4.41±0.05 D for the dipole moment along the a axis. The structure obtained has been compared with those of other related molecules.
Frequency Distribution, Specific Heat, and Young’s Moduli of Orthorhombic Polyethylene with Skeletal Approximation
Authors: Kitagawa Teizo , Miyazawa Tatsuo 
Published: July 2006

Abstract
In preliminary studies on the frequency distribution, specific heat and Young’s moduli of the orthorhombic polyethylene crystal, methylene groups were treated as single dynamic units. Intermethylene force constants were estimated from the intermolecular potential function of methane and from deBoer’s potential function. Dynamical matrices of acoustic vibrations were constructed. A practical method was worked out for deriving the frequency distribution of acoustic vibrations from the volume enclosed in constant-frequency surfaces in a three-dimensional phase-difference space. With reference to specific heat in the lowest temperature region, inter-methylene force constants were adjusted. An efficient method was used for calculating the frequency distribution of crystal vibrations of chain-polymers. The frequency distribution of orthorhombic polyethylene crystal and specific heats in low temperature region were calculated in agreement with experimental results. A simple approximate method was used for treating Young’s moduli of orthorhombic chain-polymer crystals. Applicability of the skeletal approximation is discussed.
The Relation between the Amounts of Chemisorbed and Physisorbed Water on Zinc Oxide
Authors: Morimoto Tetsuo , Nagao Mahiko 
Published: July 2006

Abstract
In the system ZnO-H2O, in which a jump appears in the adsorption isotherm, the relation between the amounts of chemisorbed and physisorbed water has been investigated, on the basis of the measurements of the water adsorption isotherms and the water content. The first adsorption isotherm of water was measured at 18°C on a sample degassed at 450°C. After degassing the sample again at 30°C, the second adsorption isotherm was obtained at the same temperature as before. The water content (Vh) on the surface of the sample was determined by the successive ignition-loss method. In the present system, the amount of water physisorbed in the first layer is composed of two parts: one (Vp1) is the amount adsorbed at lower vapor pressures, up to the beginning of the jump in the isotherm, and the other (Vp2), the amount adsorbed during the jump. The amount of water chemisorbed (Vc) during the adsorption process could be estimated as the difference between the monolayer capacities of the first and second isotherms, the total amount of chemisorbed water being the sum of Vh and Vc. The ratio of the total amount of physisorbed water (Vp1+Vp2=Vp), expressed in the number of water molecules per unit of area, to that of chemisorbed water (Vc+Vh), expressed in the number of hydroxyl groups per unit of area, was found to be about 1 : 1 in the first physisorption layer for all the samples tested, irrespective of their origin, while the ratio of Vp1 to Vp2 varied extensively with the origin of the samples.
Electronic Structure of Lone Pairs. V. Thiothiophthene and 2,5-Dimethyl-dithiofurophthene
Authors: Yamabe Hiroko , Kato Hiroshi , Yonezawa Teijiro 
Published: July 2006

Abstract
The electronic structure and the electronic transition of thiothiophthene(I) and 2,5-dimethyl-dithiofurophthene(II) are calculated by the semi-empirical ASMO SCF method. The EAB value, used instead of the bond order of the S···S bond of Compound I, and those of the S···S bond and the S···O interaction of Compound II are found to be −6.125 eV, −12.957 eV, and −0.740 eV respectively. These EAB values are compared with that of the previously-obtained transannular interaction and the hydrogen bond of water dimers calculated by the same method. The properties of the electronic transition of these compounds are discussed. No separability of the π–π*(B2)-type and σ-σ*(B2)-type transitions of the Compound I is indicated. The orbital energy of the highest occupied MO of the Compound I is remarkably high, which corresponds well with the very small Ip value.
Nuclear Magnetic Resonance in paramagnetic Solution. Proton Magnetic resonance Studies of Some Substituted Aniline Derivatives in the Presence of Paramagnetic Ni(II) and Co(II) Acetylacetonates
Authors: Yonezawa Teijiro , Morishima Isao , Akana Yoshinori , Fukuta Kazuhiko 
Published: July 2006

Abstract
To study the geometrical and electronic structures of molecules, the paramagnetic shifts of substiuted aniline proton resoances due to complexing with nickel of cobalt acetylacetonates, M(AA)2 (M=Ni or Co), were observed. The NMR spectra of sloutions containing an excess of niline derviatives and M(AA)2 show contact (for Ni(AA)2) and pseudocontact (for Co(AA)2)shift rations for various ligand protons. The contact shift ratios for N–H and N–CH3 protons reveal that the NH2 or NHR group of aniline dervatives is not coplanar with the aromatic ring for the coordinate molecules. This was confirmed by pseudo-contact shift studies.
An Application of the Oxidation Reaction between Ammonia and Bromate, Permanganate or Dichromate for the Determination of Ammonia Nitrogen in the Kjeldahl Digests without Distillation
Authors: Siddiqui M A , Bhatty M K , Ashraf Muhammad 
Published: July 2006

Abstract
Nitrogen in organic compounds, agricultural and animal products is converted into ammonium sulphate by Kjeldahl digestion. The ammonium sulphate is reacted quantitatively with hypobromite produced in situ by the addition of an excess of potassium bromate and bromide. The unutilized potassium bromate is determined iodometrically and the amount of ammonia nitrogen can be calculated from the consumed potassium bromate. Accurate results are also obtained when potassium bromate is replaced with potassium permanganate or dichromate for the determination of ammonia nitrogen in Kjeldahl digests. However, the present method is not applicable to the determination of ammonia nitrogen in undigested sample.
Kinetics of the Chromic Acid Oxidation of Glycollic and Benzilic Acids
Authors: Sengupta Kalyan K , Chatterjee A K , Moulik S P 
Published: July 2006

Abstract
The kinetics of chromic acid oxidation of glycollic and benzilic acids have been studied. Catalysis by H+ ions has been noticed in both cases of oxidation. The results show that the logarithm of the rate constants increases with increase in the proportion of acetic acid in the mixture. Ionic strength decreases the rate of oxidation. Pyridine catalyzes the oxidation of glycollic acid whereas the catalysis in the case of benzilic acid is negligible. The energy of activation and entropy of activation have been calculated. Both kinetics and spectrophotometric results indicate the formation of intermediate chromium (VI)-hydroxycarboxylate complex in each case. The complex finally decomposes to give reaction products. Glycollic acid initially produces glyoxylic acid which subsequently gives formic acid whereas benzilic acid is oxidized to benzophenone.
The Polarographic Behavior of Several α-Keto Acids in Buffered Solutions Containing o-Phenylenediamine, and Its Analytical Application
Authors: Wasa Tamotsu , Orita Morihiko , Yoshida Shingo , Musha Sôichirô 
Published: July 2006

Abstract
Such a-keto acids as glyoxylic (I), pyruvic (II), α-ketobutyric (III), mesoxalic (IV), oxalacetic (V), and α-ketoglutaric acid (VI) condense with o-phenylenediamine (OPD) to form two kinds of products, depending on the pH values of the reaction mixtures. The condensation product formed at pH values lower than 4 gives a well-defined reduction wave (E1⁄2 vs. SCE at pH 2.0: −0.490 V for I, −0.587 V for II, −0.592 V for III, −0.181 V for IV, −0.590 V for V, and −0.576 V for VI) at a potential more positive than that of free α-keto acid, while the other product, formed at pH values between 4 and 8, gives an oxidation wave (E1⁄2:−0.1–−0.2 V vs. SCE for all α-keto acids at pH 6.0). From the present polarographic investigations, it was deduced that the condensation product giving the reduction wave is probably 2-hydroxyquinoxaline derivatives and that the product giving the oxidation wave is benzimidazoline derivatives. A linear relation was obtained between the wave height for the reduction of the condensation product and the concentration ((0.5–20)×10−4 m) for each α-keto acid under appropriate conditions. The reduction wave of the condensation product was used for the determination of II in a commercial product containing II as an impurity.
The Reaction of β-Nitroalcohols and Reactive Aldehydes
Authors: Yoshimura Juji , Iida Takao , Funabashi Masuo 
Published: July 2006

Abstract
Condensation of acyclic or cyclic β-nitroalcohols with aldehydes was examined. In the case of non-protected 1-deoxy-1-C-nitro-d-glycitols and benzaldehyde, products caused by aldehyde-exchange reaction were obtained. However, the reaction of 2-methoxy-1-nitropentane or non-protected 2-nitrocyclohexanol and reactive aldehydes (formaldehyde, acetaldehyde and n-butyl glyoxylate) in the presence of sodium hydrogencarbonate gave the corresponding condensation products.
Oxidation by Transition Metal Complexes. II. Oxidation of Styrenes Catalyzed by Rhodium Compounds
Authors: Takao Kiyotomi , Wayaku Masami , Fujiwara Yuzo , Imanaka Toshinobu , Teranishi Shiichiro 
Published: July 2006

Abstract
Catalytic activities of chlorotris(triphenylphosphine)rhodium(I) and rhodium(III) chloride for the oxidation of olefins have been studied. It has been found that the complex and RhCl3 can cause catalytically the oxidation of aliphatic olefins such as styrene, α-methylstyrene or β-methylstyrene to produce carbonyl compounds under oxygen atmosphere. A remarkable solvent effect was observed in the reaction.
Study on Oxazolopyrimidines. V. Preparation of 9-Substituted Hypoxanthines via 7-Aminooxazolo[5,4-d]pyrimidines
Authors: Ohtsuka Yozo 
Published: July 2006

Abstract
Reaction of 4-cyano-5-ethoxymethylenaminooxazoles with aliphatic amines gave 7-alkylaminooxazolo[5,4-d]pyrimidines. The structure of these compounds was discussed on the basis of spectroscopic properties. These oxazolopyrimidines were converted to 9-alkylhypoxanthines by treatment with aqueous alkali (Method A) or by heating in formamide (Method B). Reaction of the ethoxymethylenamino compounds with aromatic amines gave 9-arylhypoxanthines directly (Method C).