bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Synthesis of Aziridines from β-Amino Alcohols with Triphenylphosphine Dibromide
Authors: Okada Itaru , Ichimura Kunihiro , Sudo Rokuro 
Published: July 2006

Abstract
The reaction of β-amino alcohols with triphenylphosphine dibromide was found to give the corresponding aziridines in good yields. The reaction opened a new route to the synthesis of aziridine compounds which seems to be more convenient than the Gabriel and Wenker methods. In the ring closure of ephedrine, a Walden inversion was observed. A possible mechanism is suggested.
Charge-Transfer Interaction in Linear Chain Molecular Crystals
Authors: Sakata Tadayoshi , Nagakura Saburo 
Published: July 2006

Abstract
The charge-transfer interaction is investigated theoretically for linear chain systems in molecular crystals. The charge-transfer excitation energy is shown to diverge in crystals by the usual configuration interaction method considering only one-molecule excitation. In order to overcome this difficulty, the second quantized Hamiltonian is solved with the Bose approximation for the charge-transfer exciton. Consequently, reasonable results are obtained for the stabilization of the ground state due to the contribution of many virtual excitons, for the electric dipole moment of the ground state, and for the transition moment of a charge-transfer excitation. The results correspond well to those by Mulliken’s theory for an electron donor-acceptor pair. The second quantization model is also applied in the extended form to crystals of charge-transfer complexes and ionic radicals of complex stoichiometry. The lower excited states in these crystals are understood as the coupled ones of the one-site and two-site charge-transfer configurations.
Studies on the Separation of Rare Earths. Determination of the Optimum Concentration of Ligand Ion Used in Electromigration
Authors: Ohyoshi Emiko 
Published: July 2006

Abstract
An attempt to determine the optimum concentration of ligand ion for the separation of adjacent pairs of rare earth elements by electromigration was made using the method employed for the determination of the stability constant of complex. To examine the theory, separation of lanthanum and cerium, and cerium and praseodymium was carried out using α-hydroxyisobutyric acid as a complexing agent. From the results, factors necessary for the separation of all kinds of rare earth elements were discussed.
Studies of Phenylxanthyl and Its Analogues by Electron Spin Resonance
Authors: Maruyama Kazuhiro , Yoshida Masaharu , Murakami Katsuya 
Published: July 2006

Abstract
Phenylxanthyl, phenylthioxanthyl, phenylselenoxanthyl, 9-phenylfluorenyl, dioxadehydrocoranthryl, and their derivatives were studied by the electron spin resonance (ESR) technique, and the odd-electron distribution in the radicals was examined. From the results, the angle between the plane of the phenyl group and the plane of the rest of the molecule was estimated at about 63°. Since these radicals are in equilibria with their dimers, heat of reaction in the system was also determined on two of them. Some discussion of the correlation between the heat of reaction and the molecular shape was undertaken.
Deamination of Methylenecyclopropylcarbinylamine. The Formation of a Vinyl Cation by Carbon-Carbon Bond Cleavage
Authors: Nishimura Akio , Ohta Masaki , Kato Hiroshi 
Published: July 2006

Abstract
The deamination of methylenecyclopropylcarbinylamine, prepared from ethyl methylenecyclopropanecarboxylate via the corresponding amide, gave acetylcyclopropane, methylenecyclopropylcarbinol, and 3-methylenecyclobutanol. On the basis of these results and the deuterium distribution of the deamination products of methylenecyclopropylcarbinylamine-α,α-d2, the homoallylic (III) and cyclopropylvinyl (VIII) cations are proposed as intermediates.
Charge Transfer Interaction between 2,3-Dichloro-5,6-dicyano-p-benzoquinone and Substituted Benzenes
Authors: Srivastava R D , Prasad G 
Published: July 2006

Abstract
Charge transfer complexes between 2,3-dichloro-5,6-dicyano-p-benzoquinone and various methyl and phenyl substituted benzenes have been studied. The spectral characteristics and equilibrium constants of o-, m-, and p-xylenes and those of o-, m-, and p- terphenyls are reported. The results have been interpreted in terms of Mulliken’s charge transfer theory. From the spectral data, the electron affinity of 2,3-dichloro-5,6-dicyano-p-benzoquinone has been estimated to be 1.974 eV. The energy of the first CT band has been found to be related to the ionization potential of the donors by the expression hϑCT=0.7ID−3.86.
2-Substituted Imino-1,3-dithiolanes. Their Thermal Ring-isomerizations and Reactions with Epoxides
Authors: Ueno Yoshio , Nakai Takeshi , Okawara Makoto 
Published: July 2006

Abstract
Thermal ring-isomerization and reactions with epoxides of 2-substituted imino-1,3-dithiolanes (I) were studied. The methylimino (Ia) and ethylimino derivatives (Ib) were found to be ringisomerized to the corresponding 3-alkyl-1,3-thiazolidine-2-thione (V) at about 200°C, while the phenylimino compound (Ic) was not isomerized even under more drastic conditions. The influence of various additives including Lewis acids was also examined. In contrast to the oxygen analog of I, these imino compounds were not polymerized with Lewis acids, and catalysis of any additives on isomerization was not observed. The possibility that I thermally dissociated into methyl isothiocyanate and ethylene sulfide followed by their recombination to V would be excluded by the observation that the reaction of alkyl isothiocyanate with ethylene sulfide at 150°C afforded I in good yield. Reactions of I with epoxides were carried out regarding the isomerization mechanism. All these imino compounds reacted with epoxides to give the 2-oxazolidone derivatives (III) in good yield. Mechanisms of the ring-isomerization and formation of III have been suggested, and the difference in reactivity between I and its oxygen analog has been discussed.
Determination of the Molecular Structures of AsF3 and AsCl3 by Gas Electron Diffraction
Authors: Konaka Shigehiro , Kimura Masao 
Published: July 2006

Abstract
The thermal-average distances and mean amplitudes of AsCl3 and AsF3 have been determined by gas electron diffraction. The sources of experimental errors have been discussed in detail. The observed molecular parameters are rg(As–Cl)=2.1621±0.0033 Å, θg(ClAsCl)=98°34′±34′, l(As–Cl)=0.0470±0.0024 Å, l(Cl–Cl)=0.0945±0.0063 Å, rg(As–F)=1.7089±0.0016 Å, θg(FAsF)=95°53′±22′, l(As–F)=0.0433±0.0022 Å, and l(F–F)=0.0689±0.0044 Å. The results have been compared with the structures of other trihalides of the Vb-group elements.
Polarography of Halides in Dimethylformamide. II. The Iodide Ion, the Triiodomercurate Ion, and Mercuric Iodide
Authors: Matsui Yoshihisa , Kurosaki Yukio , Date Yoshio 
Published: July 2006

Abstract
The polarographic behavior of the iodide ion, the triiodomercurate ion, and mercuric iodide at the dropping mercury electrode was investigated in dimethylformamide, using d.c. polarography, controlled potential electrolysis, and oscillographic polarography with a multi-triangular voltage sweep. The iodide ion gives two well-defined anodic waves: the first wave corresponds to the reversible oxidation of mercury to the triiodomercurate ion, and the second, to the reversible oxidation of mercury to mercuric iodide. A maximum arises on the reduction wave of the triiodomercurate ion, but it is suppressed by the addition of a small amount of polyvinyl chloride. The oscillographic polarograms and electrocapillary curves suggested that the iodide ion, like the triiodomercurate ion and mercuric iodide, is strongly adsorbed on the dropping mercury electrode. The maximum on the wave due to the reduction of the triiodomercurate ion to mercury and the iodide ion was ascribed to the convection of the mercury drop, which was itself probably caused by the abrupt desorption of the iodide ion formed successively with an increase in the negative potentials. The adsorption phenomena of the corresponding bromides and chlorides are also discussed.
An NMR Study of Metal Complexes Containing Acetylacetone and Related Compounds. I. The Preparation, Halogenation and NMR Spectra of Cobalt(III) Complexes Containing Acetylacetone and Bis(acetylacetone)ethylenediimine
Authors: Fujii Yuki 
Published: July 2006

Abstract
A mixed cobalt(III) complex containing both bis(acetylacetone) ethylenediimine and acetylacetone anions, [Co(bean)(acac)] (bean=dianion of bis (acetylacetone) ethylenediimine, acac=anion of acetylacetone), was newly prepared and its electrophilic substitution reaction at the chelate ring protone was studied by means of NCS, NBS, and NIS (NCS, NBS and NIS are the abbreviated forms of N-chloro-, N-bromo- and N-iodosuccinimide). The structures of this complex, [Co(baen)-(acac)], and of the halogenated complex were both determined to be of the β-form (cis with respect to the coordinated two oxygen atoms of baen) on the basis of their NMR spectra. The ring protons of the imine chelates were found to be more reactive than that of the acetylacetone chelate in the chlorination reaction. Then, a bi-substituted complex, [Co(baen-Cl2)(acac)], in which two chlorine atonies were attached to the two imine chelate rings, was prepared. Tri-substituted complexes, [Co(baen-X2)(acac-X)] (X=Cl, Br and I), were also prepared. The quasiaromaticity of both the acetylacetone and imine rings was considered on the basis of their NMR spectra. A new complex, [Co(baen)(OH)(H2O)], was also prepared in order to assign the NMR spectrum of the complex, [Co(baen)(acac)]. The IR, UV, and visible absorption spectra were also considered.
The Transformation of the Triphenylmethyl Radical into the Triphenylmethyl Cation in the Sulfur Dioxide - Oxygen System
Authors: Takeuchi Hiroshi , Nagai Toshikazu , Tokura Niichiro 
Published: July 2006

Abstract
The decomposition of phenylazotriphenylmethane (I) in the presence of SO2 and O2 in benzene at 60°C gives p-hydroxytetraphenylmethane (II) by the reaction of the trityl cation and the phenol formed in the reaction system. However, in the absence of O2 or SO2, the above-mentioned reaction produces trityl phenyl sulfone (III) or bistrityl peroxide (IV), without forming any II. Also, 1-diphenylmethylene-4-trityl-2,5-cyclohexadiene (Gomberg’s trityl) (V) has been chosen as the trityl radical source, and reacted with phenol in the presence of SO2 and O2 to give II as the product. However, in the absence of SO2, IV and a trace of II are formed. Moreover, in the absence of O2 in the above system, p-benzhydryltetraphenylmethane (VI) and a small amount of II are formed. The benzene solution of VI is stable on exposure to air at 60°C. Further, the UV spectrum of V in the liquid SO2-O2 system shows λmax at 405 mμ (logε 4.1) and 434 mμ (logε 4.1) (trityl chloride in 98% H2SO4: λmax 430 mμ (logε 4.58)). However, the UV spectrum of VI in the liquid SO2-O2 system has no absorption in this range. The NMR spectrum in the liquid SO2-O2 system of V exhibits only aromatic protons (2.6–3.1 τ). These facts indicate that the trityl radical generated from V is transformed into the trityl cation in the SO2-O2 system at room temperature, whereas VI does not dissociate into the trityl radical even at 60°C in benzene.
Relations between Intramolecular Energy Transfer Efficiencies and Triplet State Energies in Rare Earth β-diketone Chelates
Authors: Sato Susumu , Wada Masanobu 
Published: July 2006

Abstract
The fluorescence yield of europium chelates in several solutions varies, through its maximum value, with the increase in the energy difference between the triplet state of a ligand and the emitting level of an europium ion. The time-resolved spectroscopic measurements show that the excitation energy is transferred from the triplet state to the lower and nearest resonance level of the europium ion. The intramolecular energy transfer mechanisms for europium chelates and terbium chelates are proposed, taking the resonance exchange interaction and the thermal deactivation processes from the emitting levels of rare earth ions into consideration. Steady-state rate equations are made, and the equation of the fluorescence yield is obtained. Thus, the relations between the fluorescence yield and the triplet state energy are estimated and the fluorescence properties of rare earth β-diketone chelates may be qualitatively described.
Effects of Iodine Addition on the Electrical and Optical Properties of the Semiquinoid Phenothiazine Bromide
Authors: Matsunaga Yoshio , Shono Kosuke 
Published: July 2006

Abstract
The electrical resistivity and the electronic and vibrational spectra of the semiquinoid phenothiazine bromide have been found to be drastically modified by the addition of iodine. The resistivity minimum lies around the mole ratios of 0.25 to 0.30, while the value in this composition range is from 4 to 5 ohm cm. The combined spectroscopic data indicate three different stages in the intermolecular interactions in this system; the first around a mole ratio of 0.25, the second near 0.5, and the third above 1.00. The higher the iodine content, the less conductive the adducts appear to be. Iodine addition was attempted also to the p-phenylenediamine bromide; however, no pronounced effect on the physical properties could be found in this system.
Polarography of Halides in Dimethylformamide. III. The Chloride Ion, the Trichloromercurate Ion, and Mercuric Chloride
Authors: Matsui Yoshihisa , Kurosaki Yukio , Date Yoshio 
Published: July 2006

Abstract
The polarographic behavior of the chloride ion at the dropping mercury electrode was investigated in dimethylformamide. The chloride ion gives two diffusion-controlled anodic waves. On the basis of the analysis of the waves, the first anodic wave can be ascribed to the reversible oxidation of mercury to form either the tri- or the tetrachloromercurate ion. At the more negative part of the potential in the wave, where the concentration of the chloride ion on the mercury drop is much higher than that of the mercuric ion dissolved, the higher complex species, i.e., the tetrachloromercurate ion, is the main product of the electrode reaction. As the potential of the dropping electrode shifts toward less negative potentials, the concentration of the chloride ion at the electrode surface decreases more and more and the formation of the trichloromercurate ion becomes predominant. When a constant diffusion current is attained, only the trichloromercurate ion is formed and the formation of the tetrachloromercurate ion can be neglected. On the other hand, the second anodic wave can be ascribed to the reversible oxidation of mercury to mercuric chloride.
Mössbauer Effect of 119Sn in Some Organotin Compounds
Authors: Wynter Clive , Chandler Louis 
Published: July 2006

Abstract
Mossbauer, NMR, and infrared spectroscopy have been applied to the study of a number of organometallic tin compounds containing one or more tin manganese pentacarbonyl bonds. For the (CH3)4−nSn[Mn(CO)5]n series (n=0 to 3) a linear relation between the Mössbauer isomer shift and the number of manganese pentacarbonyl ligand was consistent with the partial isomer shift theory of 119Sn. A linear relation between the Mössbauer isomer shift and the methyl proton NMR chemical shift was also observed for this series. A plot of the isomer shift (δ0) versus the number of p holes (hp) for organotin manganese pentacarbonyl compounds established a relation δ0=1.23+0.53hp for sp3 hybridized tin. From isomer shift systematics a value of (ΔR⁄R) for 119Sn was calculated to be 1.2×10−4.
The Synthesis and Polymerization of Vinyl- and Isopropenyl-s-triazines
Authors: Yuki Yasuo , Kakurai Toshio , Noguchi Tatsuya 
Published: July 2006

Abstract
Some new vinyl monomers with an amino-s-triazinyl group were synthesized. 2,4-Amino- and substituted amino-6-vinyl-s-triazines were synthesized by the reaction of the substituted biguanides with acrylyl chloride, while 2-amino-4-substituted amino-6-isopropenyl-s-triazines were prepared from the substituted biguanides with methyl methacrylate. It has been found that vinyl-s-triazines thermally polymerized immediately after melting and gave insoluble polymers. Polymers with amino-s-triazinyl groups in the side chain were obtained by the radical polymerization of some vinyl- and isopropenyl-s-triazines. The copolymerization of these monomers with styrene has been investigated in dimethyl sulfoxide using α,α′-azobisisobutyronitrile as an initiator. The monomer reactivity ratios were determined, and the Q and e values for these vinyl-s-triazines were calculated. Some discussions are presented.
Stereochemistry and Mechanism of Catalytic Hydrogenation and Hydrogenolysis. III. Catalytic Hydrogenolysis of Benzyl-type Alcohols and Their Derivatives
Authors: Mitsui Sekio , Imaizumi Shin , Esashi Yasuyoshi 
Published: July 2006

Abstract
In order to obtain evidence for the mechanism we proposed of the catalytic hydrogenolysis of benzyl-type alcohols and their methyl ethers, optically active 2-phenyl-2-butanol (Ia), 2-phenyl-2-methoxybutane (IIa), ethyl atrolactate (Ib), and ethyl 2-phenyl-2-methoxypropionate (IIb) were hydrogenolyzed over Raney nickel and Pd(H) catalysts under hydrogen or helium atmosphere in an ethanol solution. In all cases, the hydrogenolysis proceeded stereoselectively with retention of configuration over Raney nickel catalyst but with inversion of configuration over palladium catalyst. A reverse stereoselectivity was observed when the benzyl alcohols (Ia and 2-phenyl-1,2-dihydroxypropane (Ic)) and methyl ethers (IIa) and (IIb) were hydrogenolyzed in the presence or absence of various additives over nickel catalysts. It was also found that the hydrogenolysis of benzyl alcohols always proceeds with retention of configuration over nickel catalyst containing sodium hydroxide. Various binary mixtures of Ia, IIa, Ib and IIb were hydrogenolyzed competitively over Raney nickel and Pd(H) catalysts. The order of relative rates was found to be Ia\gtrsimIb\gtrsimIIa\gtrsimIIb over Raney nickel, and IIa\gtrsimIa&gt;&gt;IIb\gtrsimIb over Pd(H) catalyst. The results support our mechanism. The catalytic hydrogenolysis is a competitive reaction of two courses (SNi type and SN2 type reactions), and the stereoselectivity reflects the difference of the free energy levels of the transition states to form π-benzylic complexes. The free energy levels of the corresponding transition states depend on stereoelectronic factor, affinity of substituents for catalyst metal, catalyst hindrance and electronic effects of substituents. The acetates (IVa) and (IVb) of Ia and IIa were hydrogenolyzed with inversion of configuration over nickel and palladium catalysts, whereas the stereoselectivity of the hydrogenolysis of the benzoate (V) of IIa depended on the kind of catalyst. The results are also explained on the basis of our mechanism.
Cationic Arylation. I. Phenylation of Substituted Benzenes with Benzenediazonium Tetrafluoroborate in Homogeneous Solution
Authors: Kobayashi Michio , Minato Hiroshi , Yamada Eiichi , Kobori Nobumasa 
Published: July 2006

Abstract
Substituted benzenes were phenylated with benzenediazonium tetrafluoroborate in homogeneous solutions with DMSO or acetonitrile. The distribution of substituted biphenyls and the partial rate factors indicated that this phenylation was an electrophilic substitution, but the selectivity was much smaller than those of nitration or sulfonylation. Experiments with chlorobenzene-4d, anisole-4d and chlorobenzene-d5 showed that both the orientation and partial rate factors did not change with deuterated compounds. Therefore, it was established that the rate-determining step was the addition of phenyl cation to an aromatic nucleus, and not the abstraction of proton from the phenylated intermediate.
Chemical Constituents of Alnus firma (BETULACEAE). I. Phenyl Propane Derivatives Isolated from Alnus firma
Authors: Asakawa Yoshinori 
Published: July 2006

Abstract
Viscous substances extracted from young shoots of Alnus firma were investigated, and two new hydroxyketones, named yashabushiketol (I) and dihydroyashabushiketol (II), trans-stiihene (III), β-phenylethyl cinnamate (IV), pinostrobin (V), alpinetin (VI), cinnamic acid (VII), paraffin hydrocarbons (n-, anteiso and iso) and triglycerides were identified on the basis of the chemical and spectral data. The biosynthetic pathways of the above aromatic compounds were discussed.
Reaction of Salicylamine with α-Dicarbonyl Compounds. II. Formation of 2,2′-Bibenz-1,3-oxazines
Authors: Kanatomi Hajime , Murase Ichiro 
Published: July 2006

Abstract
The compounds of a new type, 2,2′-bibenz-1,3-oxazine and its derivatives have been synthesized by the reactions of salicylamines with glyoxal or α-diketones in methanol at a temperature lower than 20°C. The oxazine structures were confirmed by infrared spectroscopy in solid state and by NMR spectroscopy in CCl4, CDCl3 and chlorobenzene. An oxazine-Schiff base equilibrium was observed in pyridine and in hot chlorobenzene by NMR spectra. It was found that hydrolytic decomposition of 2,2′-dimethyl-2,2′-bibenzoxazine leads to the formation of salicylidenesalicylamine through transamination. The mechanisms were investigated spectrophotometrically.
Chemical Species Produced from Some Diazaazulene Derivatives in Aqueous Solutions of Various Acidities
Authors: Tanizaki Yoshie , Hiratsuka Hiroshi , Hoshi Toshihiko 
Published: July 2006

Abstract
Making use of the isosbestic points which appear in equilibrium between two chemical species, the chemical structures of various species produced from the diazaazulene derivatives have been investigated in aqueous solutions over a wide pH range. For 1-hydro-1,3-diazaazulene-2-one (abbreviation, HDA-1), for instance, four different species exist as stable species in the respective regions; (a) the pH region higher than 12, (b) around the neutral state, (c) the pH value of ca. 1.5, and (d) the strong acid state. In the (a) region, H+ is taken off from the amino nitrogen of HDA-1 and the species becomes HDA-1−; in (b) the species takes the HDA-1 structure, as its name indicates; in (c) it takes the H+-HDA-1 structure protonated at the aza nitrogen, and in (d) it takes the H+-HDA-1-H+ structure, in which the position of the second protonation could not be clarified. In the case of 2-ethoxy-1,3-diazaazulene (EDA-2), the species corresponding to the second protonation (H+-EDA-2-H+) is hydrolyzed by acid catalysis and becomes H+-HDA-1-H+. In order to interpret the spectra of azaazulene compounds and the spectral change due to protonation, calculations by the LCAO–ASMO–SCF–CI method have been made for 1,3-diazaazulene and EDA-2. The characters of the first and the second transitions of the compounds have been satisfactorily explained by the diagrams of the AO coefficients of the LCAO-MO’s representative of the transitions.
Dielectric Relaxation and Molecular Structure. I. Dielectric Relaxation in Substituted Anilines
Authors: Srivastava K K , Vij J K 
Published: July 2006

Abstract
Measurements of static dielectric constant at 1 Mc, refractive index (for sodium D-line) and complex dielectric constant at 9.44 GHz (X-band) have been made to determine the relaxation times and dipole moments of N,N′-dimethylaniline (A), N,N′-diethylaniline (B), o-chloroaniline (C), m-chloroaniline (D) and p-chloroaniline (E) in dilute solutions of non-polar solvents. Substances A, B, C and D have been studied in n-heptane, benzene decalin and Nujol. The measurements for A and B have also been extended to cyclohexane, whereas E has only been studied in benzene. The values of relaxation time, calculated by Higasi’s equations in terms of a0, a′, a″ and a∞, and those of α, calculated from Cole-Cole’s equation in terms of the same parameters, showed an evidence for the existence of more than one relaxation mechanism. This has been interpreted in terms of the intramolecular rotations of the amino (or the substituted amino) group occurring simultaneously with the overall molecular orientation.