bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Crystal Structure of Bis(2,2′-bipyridine)nitratocopper(II) Nitrate Monohydrate [Cu(NO3)(bpy)2]NO3·H2O
Authors: Nakai Hisayoshi 
Published: July 2006

Abstract
The crystal structure of the title compound has been redetermined from diffractometer data and refined by the least-squares method to R=0.053 for 2448 non-zero reflections. The crystal is triclinic, with a=7.464(3), b=10.002(5), c=15.503(6) Å, α=111.50(5), β=91.43(5), γ=90.47(4)°, space group P\bar1, and Z=2. The copper atom has a square-pyramidal coordination very distorted by the 4 N atoms of the bipyridine ligands and one of the O atoms of the nitrato ligand at the apical position. The disposition of the 4 N atoms at the basal plane is flattened tetrahedral. The Cu atom is displaced by 0.31 Å from the mean plane of the 4 N atoms towards the apical O atom. The Cu–O and the average Cu–N distances are 2.30 and 2.01 Å respectively. In both bipyridine molecules, the two pyridine planes are twisted slightly from each other; the interplanar angle is 2.6° in one bipyridine ligand and 6.0° in the other. The mean planes of the two bipyridine molecules make an angle of 44.6°.
Absolute Rate Constants for the Reactions of O(3P) with Several Molecules
Authors: Sugawara Ko-ichi , Ishikawa Yo-ichi , Sato Shin 
Published: July 2006

Abstract
Absolute rate constants were measured for several reactions of ground-state oxygen atoms at 296±2 K. The pulse-radiolysis of O2, CO, or CO2 in the He diluent was used to produce oxygen atoms, and the atomic concentration was monitored by the resonance absorption. The measurements were made in the pressure range from 50 to 950 Torr (1 Torr \simeq133.3 Pa). The rate constants thus obtained were (2.5±0.3)×10−34 for O+O2+He and (1.0±0.2)×10−35 for O+CO+He in units of cm6 molecule−2 s−1 (1 cm6 molecule−2 s−1\simeq3.626×1035 m6 mol−2 s−1). For simple olefins, the following bimolecular rate constants (k⁄10−12 cm3 molecule−1 s−1) were obtained: Ethylene (1.0±0.2), propene (4.7±0.3), 1-butene (4.7±0.5), trans-2-butene (23±3), cis-2-butene (20±3), 2-methylpropene (17±2), 2-methyl-2-butene (55±5), 1,3-butadiene (20±2), (1 cm3 molecule−1 s−1\simeq6.022×1017 m3 mol−1 s−1). These rate constants were in fair agreement with the literature values.
Kinetic Studies on the N,N-Type Smiles Rearrangement
Authors: Sunamoto Junzo , Kondo Hiroki , Yanase Fumihiro , Okamoto Hiroshi 
Published: July 2006

Abstract
The Smiles rearrangement reaction of Dl-2-aminododecanoic acid N-methyl-p-nitroanilide to Dl-2-(p-nitrophenyl)aminododecanoic acid N-methylamide has been investigated in aqueous alkaline media containing 0–50% (v/v) acetonitrile or ethanol at 25 °C. It was found from the pH-rate profile that the reactive species is the free base form of the substrate. Acetonitrile content in the medium appreciably affected the rate with a maximum at ca. 20% in the acetonitrile content. The cationic CTAB micelles accelerated the rate 4.4-fold at pH 10, while the anionic SDS micelles suppressed the reaction almost completely. These effects of solvent and micelles were qualitatively correlated with the transition state of the reaction. A plausible mechanism for this reaction is the Smiles type rearrangement in which a spiro σ-complex is involved. The activation parameters obtained and suppression of the reaction rate by Cu(II) ion are in line with the proposed reaction mechanism.
Photolysis of Dibenzoyl Peroxide under Direct and Singlet Sensitized Irradiations. Mechanism for the Formation of the Geminate Product
Authors: Kitamura Akihide , Sakuragi Hirochika , Yoshida Masayuki , Tokumaru Katsumi 
Published: July 2006

Abstract
Attempts have been made to elucidate the mechanism for the efficient production of phenyl benzoate, the geminate product, from direct and singlet sensitized irradiations of dibenzoyl peroxide in solution. It is concluded that these irradiations produce a reactive state of the peroxide which can undergo two-bond cleavage of the O–O and C(α)–C(carbonyl) bonds to give a phenyl–benzoyloxy radical pair in a solvent cage, followed by the recombination of the component radicals to give the geminate product or by their diffusion out of the solvent cage to give diffusion products.
The γ-Ray Induced Oxidation of Aromatic Hydrocarbons in Liquid Dinitrogen Oxide
Authors: Karasawa Hidetoshi , Yugeta Rei , Sato Shin 
Published: July 2006

Abstract
The γ-ray induced oxidation of aromatic hydrocarbons has been studied in liquid dinitrogen oxide, mainly at −18°C. Various mixing ratios of dinitrogen oxide and four aromatic hydrocarbons have been examined. The main oxygen-containing products observed were the corresponding phenols and benzyl alcohols. The kinetic analysis showed that ionic species, probably N2O− ions, are the main precursors at low mole fractions of dinitrogen oxide and that oxygen atoms become important with an increase in the mole fraction. 1-Butene was used as a scavenger of oxygen atoms. The following rate constant ratios were obtained for the reactions of oxygen atoms and N2O− ions: k(O+toluene)/k(O+1-butene)=0.02, k(O+toluene)/k(O+benzene)=2.0, and k(N2O−+1-butene)/k(N2O−+toluene)=2.5. The relative rates for the formation of the corresponding phenols and benzyl alcohols through ionic reactions from aromatic hydrocarbons were obtained as follows: benzene, 1.0; toluene, 2.5; p-xylene, 2.2; 1,3,5-trimethylbenzene, 3.1. These values are quite different from the relative rate constants of the reactions of oxygen atoms with these aromatic hydrocarbons.
Calorimetric Study of the Glassy State. XV. Thermodynamic Study of Pinacol Hexahydrate and Pinacol-d2 Hexadeuterate
Authors: Oguni Masaharu , Matsuo Takasuke , Suga Hiroshi , Seki Syûzô 
Published: July 2006

Abstract
The heat capacities of pinacol hexahydrate and its deuterate analogue were measured in the temperature region between 13 and 260 K. A phase transition was found and the temperature of transition was determined to be 192.14 K for the hydrate and 191.17 K for the deuterate, respectively. The enthalpy and entropy of the transition were estimated to be 924 J mol−1 and 5.10 J K−1 mol−1 for the hydrate and 944 J mol−1 and 5.28 J K−1 mol−1 for the deuterate. The transition was interpreted as the order-disorder change of the orientations of the pinacol molecule. Besides the phase transitions, an additional anomaly was found around 150 K for the hydrate and two around 130 K and around 160 K for the deuterate, respectively. All of them are relaxational in their characteristics and interpreted as glass transitions due to freezing of reorientational motions of the water molecule and the pinacol molecule. The transition temperature and the activation enthalpy for the higher glass transition of the deuterate were estimated to be 167.2 K and (34±4) kJ mol−1, respectively.
A Spectrophotometric Study of Tributyl Phosphate Adducts of Three Bis(β-diketonato)copper(II) Complexes in Carbon Tetrachloride
Authors: Sekine Tatsuya , Tosaka Teruyuki 
Published: July 2006

Abstract
Adduct formation equilibria between bis(2-thenoyltrifluoroacetonato)-, bis(trifluoroacetylacetonato)-, and bis(hexafluoroacetylacetonato)copper(II) chelates and tributyl phosphate (TBP) in water-saturated carbon tetrachloride were studied spectrophotometrically at 25 °C. The chelates added one TBP molecule and decreased the absorption, but not very much. The formation constants obtained from the changes in the absorption, given as a function of the TBP concentration, agreed very well with those obtained previously by a solvent-extraction method.
Neutron Diffraction Study of Aqueous Ionic Solutions. II. Aqueous Solutions of Sodium Chloride and Potassium Chloride
Authors: Ohtomo Norio , Arakawa Kiyoshi 
Published: July 2006

Abstract
The structure factors Sm(Q) for aqueous solutions of NaCl and KCl at room temperature have been determined by means of the LINAC-TOF-neutron diffraction method. A revised subtraction method was applied to diffraction data of the solutions. Results obtained for the structure of the nearest hydration shell around ions are as follows, (a) The coordination numbers are 8 for Na+ and 6 for Cl− in the NaCl solution and 8 for K+ and 6 for Cl− in the KCl solution; (b) the average ion-oxygen distances are 2.50±0.10 Å for Na+, 2.70±0.10 Å for K+, and 3.10±0.05 Å for Cl−; (c) around chloride ions water molecules take the configuration to orient the vector which bisects the D–O–D angle on a straight line joining an oxygen atom and the anion. Analysis was performed on the data of LiCl and CsCl solutions.
ESR Study of the Phosphorescent State of Benzo[f]quinoline
Authors: Sekiya Hiroshi , Gondo Yasuhiko , Kanda Yoshiya 
Published: July 2006

Abstract
Electron spin resonance absorption has been observed in a single-crystal solid solution of benzo[f]quinoline in biphenyl under irradiation at 120 K with light from a high-pressure mercury lamp. The fine structure of the resonance spectrum observed at 9.25 GHz can be described by the spin Hamiltonian
H=βH·g·S+D[S_z^2-\frac13S(S+1)]+E(S_x^2-S_y^2)
in which S=1, D=±0.09926(18) cm−1, E=\mp0.04781(6) cm−1, gxx=2.0024(6), gyy=2.0018(4), and gzz=2.0018(4); the z axis is normal to the molecular plane, the x and y axes being the in-plane fine-structure principal axes. The principal x axis deviates by ±4° from the biphenyl long axis and the principal z axis by 7° from the biphenyl out-of-plane axis. The phosphorescence spectra and lifetimes have been measured both at 77 K and at 4.2 K. Marked doublet splittings were observed in the phosphorescence bands at 4.2 K, suggesting a large guest-host interaction.
An ENDOR Study of the Hindered Internal Rotation of the Cyclopropyl Group in the 2,6-Di-t-butyl-4-cyclopropylphenoxyl Radical
Authors: Shimoda Fumio 
Published: July 2006

Abstract
The ESR and ENDOR spectra were observed for the 2,6-di-t-butyl-4-cyclopropylphenoxyl radical. The assignments of the proton hyperfine coupling constants were confirmed with reference to those of the 2,6-di-t-butyl-4-methyl- and 4-(1-deuteriocyclopropyl)phenoxyl radicals. The β-proton hyperfine coupling constant for the cyclopropyl group and its temperature dependence were precisely determined. Of particular interest is the fact that the observed cyclopropyl β-proton splitting is smaller than the γ-proton splittings (A4β:0.72, A4γ1:0.83, A4γ2: 1.44 G at −70 °C). Based on the modified cos2θ rule, A4β=(1.85〈cos2θ〉−0.10)×A4Me, where the conjugative interaction between the π-system and the cyclopropyl pseudo π-orbital was incorporated, as proposed by Hudson and Bauld, the β-proton splitting was evaluated. The magnitude of the β-proton splitting and its temperature dependence were interpreted in terms of the restricted rotation of the cyclopropyl group in a two-fold potential; the stable conformation was the bisected one. The rotational barrier height, which corresponds to the difference in energy between the bisected and perpendicular conformations, was estimated to be 2.6 kcal/mol. The rotational barrier was attributed to the stabilization of the bisected conformation arising from the conjugative interaction of the aromatic and cyclopropyl moieties.
Solvent-induced Conformational Changes of Arylazo-substituted Polyaspartates
Authors: Ueno Akihiko , Takahashi Keiko , Anzai Jun-ichi , Osa Tetsuo 
Published: July 2006

Abstract
Copolymers of β-benzyl l-aspartate and β-[p-(phenylazo)phenethyl] l-aspartate were prepared and their conformations studied by circular dichroism (CD) spectroscopy. The copolymers with less than 40% azo amino acid residues were found to be left-handed (LH) helical, those with more azo amino acid residues right-handed (RH) helical in 1,2-dichloroethane (DCE) solution. The former undergo LH helix→random coil transition on addition of hexafluoro-2-propanol (HFIP) to their DCE solutions, the latter RH helix→LH helix→random coil transition on addition of HFIP. All polymers in DCE exhibit a negative CD band in the side-chain n-π* transition region. The side-chain π-π* CD band was observed only for the copolymers with the highest azo amino acid residues (67%). Its absolute ellipticity decreases with increasing HFIP content, finally disappearing at 10% HFIP. The sign of the n-π* CD band of the copolymer remains negative irrespective of the helix reversion, its absolute ellipticity being unchanged below 10% HFIP and decreasing on further increase in HFIP content. The results suggest solvent-induced changes in orientation or mobility of the side-chain phenylazo moieties.
The Preparation of 3-Phenyl[1,2,4]triazolo[4,3-a]pyridines and Their Benzologs from N-(Phenylsulfonyl)benzohydrazonoyl Chloride and Pyridines
Authors: Ito Suketaka , Kakehi Akikazu , Matsuno Toshiyuki , Yoshida Jun-ichi 
Published: July 2006

Abstract
3-Phenyl[1,2,4]triazolo[4,3-a]pyridines were obtained in good yields from N′-[α-(1-pyridinio)benzylidene]benzenesulfonohydrazidates, generated from 2-unsubstituted pyridines and N-(phenylsulfonyl)benzohydrazonoyl chloride (2), by oxidation with chloranil. The reaction of quinoline and isoquinoline with 2 gave 1-phenyl-3-phenylsulfonyl-3,3a-dihydro[1,2,4] triazolo [4,3-a]quinoline and 3-phenyl-1-phenylsulfonyl-1,10b-dihydro [1,2,4]triazolo[3,4-a]isoquinoline respectively, both in good yields; they aromatized to the corresponding triazoles by the 1,2-elimination of benzenesulfinic acid on heating.
Syntheses of 2H-1-Benzothiopyran-2-ones (Thiocoumarins) and Related Compounds from Benzenethiols and Diketene
Authors: Nakazumi Hiroyuki , Asada Akira , Kitao Teijiro 
Published: July 2006

Abstract
The products formed by the reaction of benzenethiols with diketene in the presence of H2SO4 are (E)-β-(arylthio)crotonic acids (2) and/or isomeric (Z)-β-(arylthio)crotonic acids and not, as has been reported, S-phenyl 3-oxobutanethioates (1). Compounds 1a–k, as the precursor of thiocoumarins, were prepared from benzenethiols and diketene in the presence of triethylamine. The reaction of 1 with various condensing agents has been examined to prepare 2H-1-benzothiopyran-2-ones (thiocoumarins). It is found that 4-methyl(thiocoumarins) were conveniently prepared by the reaction of 1 with anhydrous aluminium chloride in yields of 16–48%. When 1 was treated with PPA, isomeric 2-methyl(thiochromones) were preferentially obtained in yields of 5–66%, and compound 2 was isolated as an intermediate. The spectral characteristics of 4-methyl(thiocoumarins) have also been described.
Studies of Zone Melting. V. The Solid-Liquid Equilibrium and Zone Melting of the Bibenzyl–Diphenylacetylene System
Authors: Nojima Hidemoto , Akehi Seigou 
Published: July 2006

Abstract
The phase diagram of the bibenzyl–diphenylacetylene system was determined in detail from DSC by using the following equation:
T=α\sqrtF’+β,
where T is the temperature; F′, the corrected fraction melted, calculated by the use of the area for the vertex of the peak instead of the total peak area and α and β, the constants. Then, the melting and freezing temperatures were obtained from a plot of T vs. \sqrtF′ by the use of the values of β and α+β respectively. The results show the formation of solid solutions with a minimum melting point, at which difficulty in determining the composition often arises from the fact that the slopes of both the solidus and liquidus curves are zero. This could be overcome by multipass zone melting for two samples containing 20 and 30 wt % of diphenylacetylene; after 45 zone passes, the composition of the minimum melting point was found to be 26.4% at the end. Also, by Herington’s theory, it has been revealed that zone-melting experiments were attained almost at equilibrium.
The Transformation of Jervine into 18-Functional C-Nor-D-homosteroids
Authors: Suginome Hiroshi , Yonekura Norihisa , Masamune Tadashi 
Published: July 2006

Abstract
N,O-Diacetyldeoxojervine, obtained by the Wolff-Kishner reduction of jervine followed by acetylation, has been catalytically hydrogenated to (22S,25S)-N,3-O-diacetyl-5α-veratranine-3β,3β-diol. Irradiation in benzene containing mercury(II) oxide and iodine afforded 20-formyl-17β-ethyl-12α-etiojervan-3β-ol 3-acetate which was converted into 17β-ethyl-3β-hydroxy-12α-etiojervan-20-one 3-acetate by dye-sensitized photo-oxygenation of the corresponding morpholine enamine. Reduction to 17β-ethyl-12α-etiojervane-3β,20β-diol 3-acetate with sodium borohydride followed by irradiation in benzene in the presence of mercury(II) oxide and iodine afforded an 18-functional C-nor-D-homosteroid, (20R)-18,20-epoxy-17β-ethyl-12α-etiojervane-3β,20β-diol. The configuration of the methyl group on the tetrahydrofuran ring has been shown to be α on the basis of the NMR spectrum, confirming a previous assignment.
Study on V2O5–Al2O3 Catalyst by Means of XPS for the Reduction of Nitric Oxide with Ammonia
Authors: Nishijima Akio , Kiyozumi Yoshimichi , Ueno Akifumi , Kurita Minoru , Hagiwara Hiroyuki , Sato Toshio , Todo Naoyuki 
Published: July 2006

Abstract
The V2O5–Al2O3 catalyst used for the NO reduction in flue gas from a sintering furnace was studied by means of X-ray photoeloctron spectroscopy and X-ray microanalysis. Effects of dust components accumulated on the catalyst and of electronic states of vanadium ions on catalytic activities were discussed.
Analysis of the Short-range Force Including the r−s-type Functional Force
Authors: Miura Mitiko , Shiro Yuji , Murata Hiromu 
Published: July 2006

Abstract
In treating the lattice dynamics strictly, it is important to separate the short-range forces into various kinds according to their characters: covalent-bond, characteristic repulsive, and van der Waals. The purpose of this paper is to describe a method of separation and an appropriate treatment which is applicable to any crystal with any properties. For the repulsive and the van der Waals interactions, we apply the Jones-type potential function, varying as an inverse power of the distance. The results indicate that the repulsive force serves to emphasize the ionicity in the crystal-force field and that the covalent-bond force cannot be represented reasonably by the use of the valence force to such a crystal as the wurtzite structure, forming a coordination lattice.
Equilibria of Complex Formation between Bivalent Metal Ions and 3,3′-Bis[N,N′-bis(carboxymethyl)aminomethyl]-o-cresolsulfonphthalein
Authors: Murakami Sadaaki , Ogura Kotaro , Yoshino Takashi 
Published: July 2006

Abstract
The complex formation equilibria between several bivalent metal ions and 3,3′-bis[N,N′-bis(carboxymethyl)aminomethyl]-o-cresolsulfonphthalein (XO) have been investigated potentiometrically and spectrophotometrically. The metal ions studied here were Co(II), Ni(II), Cu(II), Zn(II), Pb(II), and Cd(II). The formation constants and visible-absorption-spectrum parameters of these metal complexes have been determined. It has been found that all these metal ions form 1:1 and 2:1 (metal: XO) complexes with XO. Moreover, the complex of each composition changes into one of several protonated ones depending on the pH of the solution. The probale structures of the complexes in solution are discussed.
Preparation and Spectral Properties of Oxovanadium(IV), Nickel(II), Copper(II), and Palladium(II) Complexes of Tetraaza[14]annulenes
Authors: Sakata Kazunori , Hashimoto Mamoru , Tagami Noriyoshi , Murakami Yukito 
Published: July 2006

Abstract
The oxovanadium(IV), nickel(II), copper(II), and palladium(II) complexes of 5,14-dihydrodibenzo[b,i][1,4,8,1l]tetraazacyclotetradecine and 7,8,15,16,17,18-hexahydrodibenzo[b,j][1,4,8,1l]tetraazacyclotetradecine have been synthesized, and studied by electronic, vibrational, NMR, ESR, and ESCA spectroscopy. The absorption bands appearing in the energy region greater than 16800 cm−1 were attributed to π→π* transitions within a ligand molecule and metal to ligand charge-transfer transitions. The ligand-field bands were not assigned for the present complexes, because all the ligand-field bands were obscured by the π→π* and charge-transfer bands of high intensity. The metal complexes assume the square-planar configurations since no significant absorption band was detected in the region below 17000 cm−1. A strong band appearing at ca. 1620 cm−1 was assigned to the C=N stretching mode, and this band was shifted to lower frequency upon metal coordination. A V=O streching band was observed at ca. 950 cm−1 for the oxovanadium complexes. The oxovanadium, nickel, copper, and palladium complexes showed a single nitrogen Is peak by ESCA spectroscopy, whereas the metal-free ligand, 5,14-dihydrodibenzo[b,i][1,4,8,1l]tetraazacyclotetradecine, revealed double nitrogen Is peaks. ESR spectra were measured in xylene–benzene (2: 1 v/v) as well as in the corresponding ligand matrices at room temperature. Judging from g tensors, the copper complexes were confirmed to have D2h coordination symmetry with an unpaired electron in the dxy orbital. On the other hand, vanadium(IV) is in C4v coordination symmetry with an unpaired electron in the dx2−y2.
Photoreaction of D-Nor-5α-androstan-16-one Oxime, a Steroidal Cyclobutanone Oxime
Authors: Suginome Hiroshi , Uchida Tsutomu 
Published: July 2006

Abstract
Irradiation of D-nor-5α-androstan-16-one oxime in methanol leads to a mixture of seco-nitriles; D-nor-13,16-seco-5α-androst-13(18)-ene-16-nitrile (3), D-nor-13,16-seco-5α-androst-12-ene-16-nitrile (7), 13ξ-methoxy-D-nor-13,16-seco-5α-androstane-16-nitrile (8), and 15-hydroxy-D)-nor-15,16-seco-5α-androstane-16-nitrile (9). These result from ionic α-fissions at either of the α-bonds. Low yields of three lactams, 17-aza-5α-androstan-16-one (6), 17-aza-5α,13α-androstan-16-one (11), and 16-aza-5α-androstan-17-one (5), resulting from photo-Beckmann rearrangement, are also formed. The formation of 11 is the second proven example of a photo-Beckmann rearrangement in which a chirality of the migrating carbon center is not retained in the product lactam and an intervention of a ring-opened intermediate must be involved. It was found that direction of the α-cleavage of this excited four-membered cyclic ketone oxime was not governed only by the stability of cleaved ions, since seco-nitrile 9 resulting from α-fission to a less stable primary carbonium ion was formed together with seco-nitriles 3, 7, and 8 from a more stable tertiary carbonium ion. The Beckmann rearrangement of the mixture of syn and anti oximes with thionyl chloride afforded the two expected lactams 5 and 6 together with the products of Beckmann fission 3 and D-nor-13,16-seco-5α-androst-13(14)-ene-16-nitrile resulting from a cleavage to tertiary carbonium ion.
The Confirmation of the Configuration of Ethyl 2-Bromo-3-nitro-2-alkenoate by l3C NMR Spectroscopy
Authors: Shin Chung-gi , Yonezawa Yasuchika , Ajisaka Katsumi , Yoshimura Juji 
Published: July 2006

Abstract
The configuration of the ethyl 2-bromo-3-nitro-2-alkenoate formed by the elimination of hydrogen bromide from ethyl 2,3-dibromo-3-nitroalkanoate was determined to be (Z) by the examination of the 13C NMR spectra.
Retardation of the Cleavages of Nitrophenyl 1-Adamantanecarboxylates by Cyclodextrins
Authors: Komiyama Makoto , Inoue Shohei 
Published: July 2006

Abstract
Cleavages of p- and m-nitrophenyl 1-adamantanecarboxylates (1 and 2) were carried out in the presence of α-, β-, and γ-cyclodextrins at 16 °C. The complex formation of 1 with α-, β-, and γ-cyclodextrins decelerated its cleavage by 3.2, 28, and 13 fold, respectively, in the 99 : 1 (v/v) mixture of 0.1 mol dm−3 NaOH aqueous solution and acetonitrile. All α-, β-, and γ-cyclodextrins showed decelerations of the cleavages of 1 and 2 also in the 66 : 34 mixture of 0.1 mol dm−3 NaOH aqueous solution and acetonitrile, although the magnitudes of the rate effects were smaller. The decelerations of the cleavages of 1 and 2 by cyclodextrins were markedly in contrast with the accelerations of the cleavages of other phenyl esters by cyclodextrins previously reported, and were ascribed to the formation of the complexes, in which 1 and 2 were protected sterically and/or electrostatically by cyclodextrins.