bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Hydrolysis of Some Sterically Protected 1-Aza-3-phosphaallenes
Authors: Niitsu Takashi , Inamoto Naoki , Toyota Kozo , Yoshifuji Masaaki 
Published: July 2006

Abstract
Some sterically protected 1-aza-3-phosphaallenes carrying 2,4,6-tri-t-butylphenyl group were prepared and the hydrolysis reactions of these azaphosphaallenes were studied.
A New, Highly Efficient, and Simple Procedure for the Construction of Medium-Sized Nitrogen Heterocyclic Ring System
Authors: Babu B Ramesh , Goto Mutsuo , Higaki Masato , Sugiyama Takashi , Nakamura Kaoru , Ohno Atsuyoshi 
Published: July 2006

Abstract
Two types of sulfur- and nitrogen-containing heterocycles have been synthesized from a tetrahydro-4-oxothiophene derivative.
Preparation and Characterization of Activated Carbon Tablets for Electric Double Layer Capacitors
Authors: Tanahashi Ichiro , Yoshida Akihiko , Nishino Atsushi 
Published: July 2006

Abstract
Two types of activated carbon tablets (AC tablets) were prepared and characterized by adsorption methods for electric double-layer capacitors. The tablets were prepared from either the activation or carbonization of molded mixtures comprising phenolic resin-based activated carbon powders and phenolic resins. The specific surface area of the tablets (a) prepared from activation was 2010 m2g−1 and the bulk density was 0.45 gcm−3. The area of tablets (b) from carbonization was 1400 m2g−1 with a yield of 83% (weight of obtained tablets/weight of molded mixtures). The capacitance of the capacitors with tablets (a) showed 7.3–12.5 F/(cm3 of AC tablets). The reliability of the capacitors with AC tablets (a) and (b) was improved in comparison with that of capacitors with polarizable electrodes comprising activated carbon powders and binders.
Unit Subduced Cycle Indices and the Superposition Theorem. Derivation of a New Theorem and Its Application to Enumeration of Compounds Based on a D2d-Skeleton
Authors: Fujita Shinsaku 
Published: July 2006

Abstract
A combination of the concept of unit subduced cycle indices (USCIs) and the Redfield–Read superposition theorem affords a new methodology of enumerating geometrical objects such as molecules and polyhedra. This method allows us to enumerate such objects with respect not only to their constitutions but also to their symmetries, in which subduced cycle indices (SCIs) derived from USCIs play an important role. Further derivation of a cycle index from the SCIs and its incorpotation with the superposition theorem are also discussed. The inverse of the mark table and the table of USCIs for D2d point group are presented for further applications of the USCI approach.
Conductometric Study of Calcium(II), Strontium(II), and Barium(II) Perchlorates in Methanol–Ethylene Glycol Mixtures
Authors: Doe Hidekazu , Ohe Hiroshi , Matoba Hiroyuki , Ichimura Akio , Kitagawa Toyokichi 
Published: July 2006

Abstract
The ion-association constants, K1A, of an ion pair, M2+ClO4− (M=Ca, Sr, Ba), have been determined by conductometric measurements in methanol–ethylene glycol mixtures of 0, 20, 40, 60, 80, and 100 wt% of ethylene glycol at 5, 15, 25, 35, and 45 °C. The conductometric data were treated by an improved Fuoss and Edelson method. The thermodynamic functions of ΔH1A\ominus and ΔS1A\ominus have also been determined at 25 °C from the temperature dependence of K1A. In 60–80 wt% of ethylene glycol the K1A values of these metal perchlorates are similar to each other, since the characteristics of individual metal ions are probably depressed by the strong solvations of those cations. The results are discussed while considering the cation solvation and structure of a bulk solvent.
Coincidence Mössbauer Spectroscopic Study of 57Co-Labelled CoSeO4 and CoSeO4·H2O
Authors: Watababe Yasuo , Nakada Masami , Endo Kazutoyo , Nakahara Hiromichi , Sano Hirotoshi 
Published: July 2006

Abstract
KX-Ray-gated emission Mössbauer spectra and time-resolved emission Mössbauer spectra of 57Co-labelled CoSeO4 and CoSeO4·H2O were measured at room temperature using a coincidence technique. No difference in the area intensity ratio of 57Fe(II) to the sum area intensity of 57Fe(II) and 57Fe(III) was observed for anhydrous CoSeO4 between the KX-ray-gated and non-gated emission spectra; a larger area intensity of 57Fe(II), however, was observed for the KX-ray-gated sectrum of CoSeO4·H2O than for the non-gated one. This difference is attributed to different local radiolytic effect of the deexcitation processes between KX-ray and Auger electron emission. The time-dependence in the area intensity ratio of 57Fe(II) to the sum area intensity of 57Fe(II) and 57Fe(III) was observed for CoSeO4·H2O. The relaxation process observed for CoSeO4·H2O by its time-resolved spectrum indicates that the radicals formed in the EC-decay oxidize 57Fe(II) on the time scale of the nuclear lifetime of the first excited state of 57Fe, and that a radical reaction plays an important role in determining the relaxation time.
Interfacial Phenomena in Ion-Association Extraction Kinetics of Iron(II) with 1,10-Phenanthrolines
Authors: Watarai Hitoshi , Sasaki Koh , Sasaki Naoko 
Published: July 2006

Abstract
The role of the interface in ion-association extraction kinetics of iron(II) with 1,10-phenanthroline(phen), 4,7-dimethyl-1,10-phenanthroline(DMP) or 4,7-diphenyl-1,10-phenanthroline(DPP) from sodium salt solutions was investigated by means of a high-speed stirring technique and a stopped-flow method. The initial extraction rates of the ion pairs were proportional to the first order of both iron(II) and the ligand concentrations in all cases studied; it was therefore suggested that the rate-controlling step is the formation of mono-complexes. From analyses using the adsorption constants and the distribution constants of the ligands and the formation-rate constants of the mono-complexes in the aqueous phase it was concluded that the location where the rate-controlling reaction takes place depends on the ligands: a bulk aqueous phase in phen, an interface in DPP, and both of a bulk aqueous phase and an interface in the case of DMP. The extraction rates were apparently reduced by an interfacial adsorption of the ion pairs, which was governed by the hydrophobicity of the ligands and the hydrophilicity of the counter anions.
New Column Packing Materials for Separation of Water-Soluble Vitamins by High-Performance Liquid Chromatography
Authors: Akiyama Shuzo , Nakashima Kenichiro , Shirakawa Nanako , Yamada Kyoko 
Published: July 2006

Abstract
Three types of high-performance liquid chromatographic column packing materials ((3-morpholinopropyl)-, [3-(1-piperazinyl)propyl]-, and (3-piperidinopropyl)silyl silica gels) were newly prepared and examined for their ability to separate water-soluble vitamins. Six vitamins (ascorbic acid, nicotinic acid, thiamine hydrochloride, pyridoxine hydrochloride, hydroxocobalamin acetate, and flavin adenine dinucleotide) in sample solutions could be completely separated within less than 12 min by UV detection on a column packed with morpholinopropylsilyl silica gel by using a phosphate buffer [0.1 M (1 M=1 moldm−3) H3PO4−0.1 M Na2HPO4 (pH 6.0) containing 10 mM tetrabutylammonium bromide] as an eluent. This efficient gel was successfully applied to vitamin analyses of commercially available healthful beverages. The other column packing materials also showed characteristic for specific water-soluble vitamin analysis. Typical separations are presented.
Nucleophilic Reaction upon Electron-Deficient Pyridone Derivatives. X.One-Pot Synthesis of 3-Nitropyridines by Ring Transformation of 1-Methyl-3,5-dinitro-2-pyridone with Ketones or Aldehydes in the Presence of Ammonia
Authors: Tohda Yasuo , Eiraku Miyuki , Nakagawa Takao , Usami Yumi , Ariga Masahiro , Kawashima Toshihide , Tani Keita , Watanabe Hiroko , Mori Yutaka 
Published: July 2006

Abstract
The reaction of 1-methyl-3,5-dinitro-2-pyridone (1a) with ketones or aldehydes in the presence of ammonia gave alkyl- and/or aryl-substituted 3-nitropyridines (6) in moderate to high yields. Enamines derived from the ketones gave better results than did the ketones themselves; on the other hand, those derived from the aldehydes gave no 6 at all. On the basis of deuterium-labeled experiments, a mechanism comprising competitive ring transformations of 1a is proposed.
Orbital Tilting and Hybridization Change. An Illustrational Molecular Orbital Approach to an Addition (CH2=CH2+HBr→CH3CH2Br) and an Elimination Reaction (CH3CH2Br/Base→CH2=CH2)
Authors: Ito Suketaka , Kakehi Akikazu 
Published: July 2006

Abstract
Configuration alteration and hybridization change in the addition of hydrogen bromide to ethylene and those in its reverse, E2-type reaction were illustrated in terms of orbital tilting on the basis of the concept of stabilizing and destabilizing second order orbital interactions. The predominancy of trans fashion in these reactions are also visualized qualitatively.
Asymmetric Cycloaddition of N-Metalated Azomethine Ylides with the Optically Active α,β-Unsaturated Esters Derived from α-Amino Acids
Authors: Kanemasa Shuji , Yamamoto Hidetoshi , Wada Eiji , Sakurai Tosio , Urushido Kunio 
Published: July 2006

Abstract
α,β-Unsaturated esters bearing a chiral oxazolidine or perhydropyrrolo[1,2-c]imidazole auxiliary at the β-position have been prepared and applied to the cycloadditions with N-metalated azomethine ylides derived from α-(benzylideneamino) esters. These reactions are found to proceed with an exclusively high diastereofacial selectivity to give 2,4-pyrrolidinedicarboxylates with four consecutive chiral centers after the removal of chiral auxiliary. Detailed stereochemistry in the transition state is discussed.
Fundamental Study on the Production of Ultrapure Water VIII. Removal of Leachables from Mixed-Bed Ion Exchange Resins
Authors: Agui Wataru , Takeuchi Masahito , Abe Masahiko , Ogino Keizo 
Published: July 2006

Abstract
A study was made concerning the removal of leachables released from mixed-bed ion exchange resins. The key concerns were to determine the optimum mixed ratio of strong acid cation exchange resins (SACERs) and strong base anion exchange resins (SBAERs), which give the minimum value of total organic carbon (TOC) released from the resin mixtures and to investigate the effect of synthetic carbonaceous adsorbents on the adsorption of the leachables. The leaching rates of the leachables from the resin mixtures were dependent on the mixed ratios of SACERs and SBAERs. The TOC value for the leachables showed a minimum for a SACER-to-SBAER volume ratio of 9:1, far different from the mixed ratio in ordinary water treatment. The release of leachables from resin mixtures was mainly due to SBAER. The carbonaceous adsorbent having a higher hydrophobic surface adsorbed the leachables well from the resin mixtures.
Preparation and Characterization of cis- and trans- [RhCl2(dmap)2]+ (dmap=1,3-bis(dimethylarsino)propane), and X-Ray Structure Analyses of These Complexes and trans-[CoCl2(dmap)2]+
Authors: Simonsen Kim , Hamada Masatoshi , Suzuki Nahomi , Kojima Masaaki , Ohba Shigeru , Galsbøl Frode , Saito Yoshihiko , Fujita Junnosuke 
Published: July 2006

Abstract
The cis- and trans- [RhCl2(dmap)2]+ (dmap=1,3-bis(dimethylarsino)propane) complexes were prepared by reaction of RhCl3·3H2O with dmap, and the molecular structures of these complexes were determined by the single crystal X-ray diffraction method. Crystal data and final R values are: trans-[RhCl2(dmap)2]ClO4 (1), monoclinic, Cc, a=20.018(4), b=10.229(1), c=12.972(2) Å, β=99.98(2)°, V=2616(1) Å3, Z=4, R=0.034 for 1298 observed unique reflections. cis-[RhCl2(dmap)2]PF6 (2a), orthorhombic, Pca21, a=14.699(2), b=9.381(2), c=19.640(9) Å, V=2704(1) Å3, Z=4, R=0.086 for 1284 reflections. cis-[RhCl2(dmap)2]CF3SO3 (2b), orthorhombic, Pca21, a=14.700(3), b=9.381(4), c=19.644(8) Å, V=2709(2) Å3, Z=4, R=0.088 for 1094 reflections. The Rh–As distances in the linear As–Rh–As groups are 2.442(4)–2.454(4) Å (av 2.446(4) Å) for (1), 2.345(4) and 2.484(6) (av 2.415(6) Å) for (2a), and 2.389(10) and 2.441(10) Å (av 2.415(10) Å) for (2b), while those in the linear As–Rh–Cl groups are 2.385(3) and 2.370(4) Å (av 2.378(4) Å) for (2a), and 2.387(4) and 2.367(5) Å (av 2.377(5) Å) for (2b). The molecular structure of trans-[CoCl2(dmap)2]Clo4 (3) was also determined by the X-ray method. Crystal data and the final R value are: orthorhombic, Pccm, a=8.018(2), b=8.428(1), c=18.716(3) Å, V=1265 Å3, Z=2, R=0.095 for 1072 reflections. A series of trans-[RhX2(dmap)2]+ (X=Cl, Br, I) were prepared and their absorption spectra were compared with one another and with those of related complexes.
Mercury-Photosensitized Decomposition of 2-Azetidinone and 4,4-Dimethyl-2-azetidinone
Authors: Yamamoto Shunzo , Kanetsuki Akihide , Sueishi Yoshimi , Nishimura Norio 
Published: July 2006

Abstract
The mercury-photosensitized decompositions of 2-azetidinone(AZ) and 4,4-dimethyl-2-azetidinone(DMAZ) have been studied at 453 and 423 K and at pressures from 750 to 18000 Pa and from 640 to 5000 Pa, respectively. The major products from AZ were carbon monoxide and ethylene, while ammonia was a minor product. The yields of carbon monoxide and ethylene increased linearly with increasing reaction time and light intensity; they were independent of the AZ pressure. These results suggest that carbon monoxide and ethylene are the primary products. The major products from DMAZ were carbon monoxide, isobutene, and 2,2-dimethylaziridine; ethane, isobutane, and propylene were the minor products. The yields of carbon monoxide, isobutene, and dimethylaziridine increased linearly with increasing reaction time and light intensity at 3800 Pa, showing that these products are the primary ones. The formation of minor products was not linear with time. The quantum yields of carbon monoxide and isobutene were independent of the DMAZ pressure, while the relative yield of dimethylaziridine to that of carbon monoxide increased and those of the minor products decreased with an increase in pressure. Plausible mechanisms were proposed.
Gamma Radiolysis of Cu(II) Complex of Metronidazole
Authors: Mandal P C , Bardhan D K , Bhattacharyya S N 
Published: July 2006

Abstract
Aqueous solutions of Cu(II) Metronidazole (CuIIM) at neutral pH were irradiated with 60Co γ-rays under different conditions of radiolysis. The radiolytic formation of HNO2 and CuI was followed. The radiolytic yields of chromophore loss of CuIIM were also determined under different conditions. The OH radicals attack the metal complex to give the OH adducts of the ligand at C2, C4, and C5 either directly or through the formation of Cu(III) species. The C5–OH adduct, however, undergoes oxidative denitration and as a result the metal complex is decomposed. The OH adducts also undergo electron transfer to CuII ion to give reduced complex. No denitration was observed due to the reaction of eeq− with the metal complex. On the other hand, the nitro group of the ligand in the complex undergoes successive 4-electron reduction to give hydroxylamino derivative. From the competition kinetics using t-butyl alcohol as the scavenger of OH in N2O saturated solution of the metal complex, the rate constant for the reaction of OH with complex was evaluated to be ca. 2.1×109 dm3mol−1s−1 which is of the same order as that observed in the case of free metronidazole.
Determination of the Configuration of Diastereoisomers of 2-Alkyl-3-hydroxybutanoates with Gas Chromatography
Authors: Nakamura Kaoru , Miyai Takehiko , Nagar Ashish , Babu B Ramesh , Ando Takashi , Ohno Atsuyoshi 
Published: July 2006

Abstract
Diastereoiscomers of 2-alkyl-3-hydroxybutanoates are separated by gas chromatography. The threo (anti)-isomers have shorter retention times than those of the corresponding erythro (syn)-isomers.
On Tautomerism and Self-Association of 2-Pyridinol/2-Pyridone System
Authors: Millefiori Salvatore , Millefiori Arcangelo 
Published: July 2006

Abstract
The semiempirical “Effective Pair Correlation Energy” method of Sinanoglu et al. has been employed to investigate the role of the electron correlation energy in the cis-trans, protomeric and dimerization equilibria in the 2-pyridinol (HP2)/2-pyridone (P2) system. CNDO/2 wave functions were used throughly. Preliminary calculations on test cases formic acid, water dimer, and ammonia-water dimer gave acceptable figures in comparison with more accurate literature data. The results show that in HP2 the N–C–O–H cis isomer is more stable than the trans isomer by 2.7 kJ mol−1. Correlation energy favors the trans isomer by 2.9 kJ mol−1 and the keto P2 form over the HP2 form by 11.3 kJ mol−1, in qualitative agreement with results of ab initio calculations. The correlation energy term is stabilizing for the associative process of both tautomers. The numerical data are greatly dependent on the intermolecular equilibrium distance, the best results being obtained at experimental equilibrium distances. (P2)2 dimer is correctly predict to be more stable than (HP2)2 dimer. The correlation energy contribution amounts to 22 and 12.4 kJ mol−1 per hydrogen bond in (HP2)2 and (P2)2, respectively.
Effect of Fe(III) Ions on the γ-Radiolysis of Thymine
Authors: Bhattacharyya S N , Mandal P C , Chakrabarti S 
Published: July 2006

Abstract
Aqueous solutions of thymine (T) in the presence of Fe(III) were irradiated under deaerated conditions at pH ≈2. The products of radiolysis were separated by two dimensional thin-layer chromatography. In the absence of any metal ion, the G(-T) is 2.6 but when Fe(III) is present during radiolysis, the G(-T) increases significantly and reaches a limiting value of 3.2. The yields of the hydroxylated products of thymine also increase in the presence of Fe(III). The results were explained by a mechanism which involves the interactions of Fe(III) with the transient adducts of thymine.
Conformation of 1-Methyl-3,4-benzo-7-thia-2-azabicyclo[3.3.1]non-3-ene 7-Oxide
Authors: Hatano Keiichiro , Takeuchi Isao , Hamada Yoshiki , Yashiro Tamotsu , Kurono Yukihisa 
Published: July 2006

Abstract
The crystal and molecular structures of 1-methyl-3,4-benzo-7-thia-2-azabicyclo[3.3.1]non-3-ene 7-oxide have been determined on the basis of three-dimensional X-ray data. The six-membered thiane ring in this novel tricyclic system has been elucidated to adopt a chair-type conformation with an axial-axial aza-phenyl substituent and an equatorial sulfinyl group. The conformation in the solid state was consistent with that previously proposed by molecular mechanics calculations.
Hydrogen Isotope Equilibration of HD on MgO below Room Temperature
Authors: Ito Tomoyasu , Tominaga Nobuyuki , Tashiro Toshihiko , Toi Keio , Ikemoto Isao , Kobayashi Hisayoshi 
Published: July 2006

Abstract
MgO pretreated at ca. 823 K in vacuo showed the highest catalytic activity for an isotope equilibration reaction, 2HD=H2+D2, at 195 K. This reaction proceeds through an interaction of dissociatively adsorbed hydrogen on a pair site consisting of lowly coordinated ions, MgLC2+–OLC’2− residual OH− at the nearest lattice position.
A New Syntheic Route to Hexachloromolybdate(III). An X-Ray Structure of (NH4)3[MoCl6]
Authors: Shibahara Takashi , Yamasaki Mikio 
Published: July 2006

Abstract
Ammonium hexachloromolydbate(III) (NH4)3[MoCl6] was obtained by tin metal reduction of ammonium molybdate in high yield (80%). The X-ray structure was determined. Crystal data: tetragonal system, space group P42/m, a=8.822(3) Å, c=7.271(2) Å, V=565.9(3) Å3, Z=2, R(Rw)=3.35(5.47). Two independent Mo–Cl distances (2.439(2) and 2.451(1) Å) exist.
Effect of Trace Water in Chloroform on Coordination Mode of the Tetraazamacrocyclic Complex Comprised of Nickel(II) Bromide and 7R(S),14S(R)-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane
Authors: Mochizuki Katsura , Suwabe Masaaki , Ito Tasuku 
Published: July 2006

Abstract
Trans-[NiBr2L](L= the titled macrocyclic ligand) dissolves in freshly purified chloroform containing a very small amount of water to give an equilibrium mixture between the low-spin four coordinate and the high-spin six coordinate complexes. High temperature favors the high-spin form. This is opposite to the well-known behavior of equilibria in H2O between low-spin four coordinate and high-spin six coordinate nickel(II) complexes with similar tetraaza macrocyclic ligands. Trace water in chloroform facilitates the formation of the low-spin species.
Halogenation Using Quaternary Ammonium Polyhalides XXVII. Chloroiodination of Alkenes with Benzyltrimethyl ammonium Dichloroiodate
Authors: Kajigaeshi Shoji , Moriwaki Masayuki , Fujisaki Shizuo , Kakinami Takaaki , Okamoto Tsuyoshi 
Published: July 2006

Abstract
The reaction of alkenes with benzyltrimethylammonium dichloroiodate in dichloromethane gave the chloro iodo adducts in anti-stereospecific and regioselective manner; in methanol these adducts were obtained along with methanol-incorporated products.
Convenient Alkylation of 6,7-Dihydro-7-5H-pyrrolo[3,4-b]pyridin-5-ones in a Phase Transfer System. Synthesis of Novel Cyclic Nicotinamide Analogs
Authors: Goto Takehiko , Endo Mikihiro , Saito Minoru , Sato Ryu 
Published: July 2006

Abstract
The title reaction is readily achieved with alkyl halides in the presence of sodium hydroxide and a phase transfer catalyst to afford 7-alkylated derivatives in good yields. The present reaction involving intramolecular double-alkylation at C-7 and N-6 with dihalides leads to novel fused heterocyclic systems.
Photosolvolysis of 2-Alkoxy-2-phenyl-1,3-dithiolane
Authors: Okuyama Tadashi , Haga Naoki , Fueno Takayuki 
Published: July 2006

Abstract
2-Methoxy- and 2-ethoxy-2-phenyl-1,3-dithiolane are hydrolyzed to the thioester in neutral aqueous solution by irradiation with a low-pressure Hg lamp. Irradiation of a solution of the alkoxy dithiolanes in alcohol induces easily the alcohol exchange.
Statistical Thermodynamic Study of Liquid Organic Compounds
Authors: Kawai Satoshi , Arakawa Kiyoshi 
Published: July 2006

Abstract
A statistical thermodynamic study of liquid organic compounds has been worked out on the basis of a liquid model: a liquid is regarded as an assembly of particles immersed in a uniform background potential resulting from the attractive forces between molecules. In the model the equation of state is expressed as a sum of the term derived from the analytical solution of the Percus–Yevick equation and that from the background potential. Calculations of thermodynamic functions for five liquids (benzene, carbon tetrachloride, toluene, chloroform, cyclohexane) have been performed. The results show the effectiveness and reasonableness of the theory with the evidence of coincidence of calculated values and observed ones.
Detection of Odorous Substances by Using a Lipid-Coated Quartz-Crystal Microbalance in the Gas Phase
Authors: Okahata Yoshio , Shimizu Osamu , Ebato Hiroshi 
Published: July 2006

Abstract
The adsorption behaviors and partition coefficients of various odorants and perfumes in a lipid matrix were measured in the gas phase using a dimethyldioctadecylammonium poly(styrene-4-sulfonate) multibilayer film-coated quartz-crystal microbalance (QCM), the resonance frequency of which changes linearly with increasing the absorption amount on the lipid matrix on the QCM. A good correlation was observed between the partition coefficients of various odorous substances or perfumes in the lipid matrix and the odor intensity in humans obtained by smelling tests for the same compounds. A similar relation was observed regarding the absorption behavior to an olfactory epithelium-coated QCM in the gas phase. Odorant having a strong intensity showed higher adsorption in the lipid matrix on the QCM. The partition coefficients increased in the solid state of the lipid matrix, compared with the fluid-liquid crystalline state. As compared with absorption experiments in the aqueous phase, the high partition coefficients of odorants in the lipid matrix and the good correlation between the partition coeffcients and the odor intensity in humans were observed in the gas phase.