bluuebunny/crossref_metadata_2025 huggingface dataset:
The Reaction of Nitriles with Phosgene. VII. Synthesis of α,β-Unsaturated Isocyanates
Authors: Ohoka Masataka , Yanagida Shozo , Sugahara Kenji , Fujita Tetsuo , Okahara Mitsuo , Komori Saburo
Published: July 2006

The reaction of nitriles with phosgene in the presence of hydrogen chloride was carried out for synthesizing α,β-unsaturated isocyanates. 3-Chloropropionitrile, 2,3-dichloropropionitrile, isobutyronirtile, and 2-chloromethylpropionitrile gave the corresponding α-chloro-α,β-unsaturated isocyanates in moderate yields (27–50%). Propionitrile, n-butyronitrile, and 3-phenylpropionitrile gave the corresponding pyrimidines as the major product. 3-Phenylpropionitrile, however, gave the isocyanate as the major product when the amount of benzene as a solvent increased. Reaction pathways to isocyanates and pyrimidines were discussed.
Semiconducting Properties of Ln2CuO4 (Ln=Rare earths)
Authors: Kenjo Tadao , Yajima Seishi
Published: July 2006

The temperature dependence of the resistivity and the thermoelectric power of Ln2CuO4 (Ln=rare earths) have been measured. The compounds of Gd, Sm, Nd, and Pr are semiconductive, while La2CuO4 shows metallic conductivity. The tetragonal lattice of La2CuO4 shrinks in the a axis and expands in the c axis compared to Pr2CuO4, in spite of the steady expansion of these lattice parameters for the compounds between Gd and Pr. The thermoelectric power of Ln2CuO4, but not La2CuO4, is negative, suggesting an electron-conducting or n-type semiconductor. The resistivity of the Ln2CuO4 at room temperature increases essentially with an increase in the atomic number of Ln. The plots of the thermoelectric power vs. the reciprocal temperature showed a steeper slope for the compounds of the heavier rare earths. The semiconductor-metal transition observed between La2CuO4 and Pr2CuO4 was explained in relation to the structural change (the shrinkage of the a axis and the expansion of the c axis) as being due to the change in the electron configurations of Cu2+.
Interpretation of Photoelectron Spectra of Halomethanes
Authors: Katsumata Shunji , Kimura Katsumi
Published: July 2006

Theoretical studies of the electronic structure of chloromethanes (CH4−nCln, where n=1∼4) were carried out by the CNDO/2 method. The resulting Koopmans’ theorem ionization energies were generally in good agreement with the experimental data available, and somewhat different assignments from those previously reported were obtained for the nonbonding orbitals. A “sum rule” was employed for interpreting the photoelectron bands of three series of di- and poly-halomethanes (chloro-, bromo-, and iodo-methanes) in terms of some localized molecular orbitals. Reasonable assignments were derived for the photoelectron spectra of all these halomethanes and the resulting assignments for the chloromethanes were in good accord with those obtained from the CNDO/2 calculation.
Dielectric Studies on Isobutyl Halides in the Liquid State
Authors: Das Arati , Ghatak Alpana , Hasan Abul
Published: July 2006

The activation energies of dielectric relaxation ΔHτ in three isobutyl halides in the liquid state are found to be almost equal to the mean value of the electrostatic self energies of the trans and gauche isomers in the corresponding compounds. The energy difference between the two isomers in the liquid state obtained from the dipole moment measurements agree well with those obtained by the spectroscopic method.
On the MO Perturbation Theory of Molecular Rearrangements
Authors: Fujimoto Hiroshi , Miyagi Morio , Yamabe Shinichi , Fukui Kenichi
Published: July 2006

The relationship between two simple Hückel MO perturbation treatments of electrocyclic reactions formerly proposed has been examined. The reason why the two different approaches give the same prediction with regard to the favorable paths of the reactions has been established numerically. A calculation of the thermal ring-closing of butadiene has been carried out, including both sigma and pi electrons.
An X-Ray Redetermination of the Crystal Structure of Tin(II) Chloride Dihydrate
Authors: Kiriyama Hideko , Kitahama Katsuki , Nakamura Osamu , Kiriyama Ryôiti
Published: July 2006

The crystal structure of tin(II) chloride dihydrate, SnCl2·2H2O has been redetermined by a single crystal X-ray diffractometer technique. The crystal is monoclinic, space group P21⁄c with a=9.313, b=7.250, c=8.970 Å, β=114°55′ and Z=4. The structure was solved by three-dimensional Patterson and electron density syntheses. An anisotropic least-squares refinement, based on 1695 independent reflections gave an R value of 0.04. The tin(II) atom forms a pyramidal complex with two chlorine atoms and one oxygen atom; the bond lengths in the pyramid are Sn–O, 2.33 and Sn–Cl, 2.50 and 2.56 Å and the bond angles are 86.9, 85.0, and 87.9°. These results support a view that the bonding in dichloroaquotin(II) complex is considerably ionic in character. This crystal consists of double layers of the aquocomplex, SnCl2·(OH2), parallel to (100) with intervening layers of the second water molecules. Both kinds of the water molecules are linked together by hydrogen bonds of 2.74, 2.79, and 2.80 Å into two-dimensional networks. The structure reported previously was found to be in error, although its essential feature was quite similar to the present one.
Ion-Solvent Interaction of Tetraalkylammonium Ions in Solvents of High Dielectric Constant. III. Conductance and Walden Product of Some Partially Substituted Alkylammonium Ions in N-Methylacetamide and N-Methylpropionamide at Different Temperatures
Authors: Singh Raj Deo
Published: July 2006

Ion-solvent interaction of some partially substituted alkylammonium ions in N-methylacetamide (NMA) and N-methylpropionamide (NMP) has been investigated from the point of view of electrical conductance and the derived Walden product. From the results, it seems that like tetraalkylammonium (R4N+) ions, Me3NH+ and CeMe3N+ ions are structure breakers in these solvents while Me3PhN+ ion is neither structure breaker nor structure maker.
Transmission of Substituent Effects through Oxygen and Sulfur Atoms. I. 1H Chemical Shifts of Ring-substituted Phenyl Vinyl Ethers and Sulfides
Authors: Fueno Takayuki , Kajimoto Okitsugu , Izawa Kunisuke , Masago Mitsuru
Published: July 2006

The proton chemical shifts of the vinyl group in ring-substituted phenyl vinyl ethers (PVE) and sulfides (PVS) were measured and related to the Hammett σ constants. It was found that the ρ value for the β-trans proton of PVS, −0.448 τ⁄σ, is greater in magnitude than that of PVE, −0.378 τ⁄σ, in contrast to the tendency reported for the methyl hydrogens in anisole and thioanisole. The results can best be explained in terms of the concept of the through-conjugative (pπ-dπ-pπ) behavior of the sulfur atom interposed between two unsaturated groups.
Transmission of Substituent Effects through Oxygen and Sulfur Atoms. II. 13C Chemical Shifts of Ring-Substituted Phenyl Vinyl Ethers and Sulfides
Authors: Kajimoto Okitsugu , Kobayashi Masaru , Fueno Takayuki
Published: July 2006

The 13C chemical shifts of ring-substituted phenyl vinyl ethers and sulfides were measured and discussed in relation to the change in electron distribution caused by the ring-substitution. The Hammett plots of the shifts for the terminal carbon confirm the greater transmission efficiency of sulfur atom. An “inverse” substituent effect was found for the α-carbon of both compounds. This suggests that the bond-polarization plays an important role in the transmission of electronic effect.
Bond Orbital Calculations on the Methane and Silane Molecules
Authors: Kohda Susumu , Katagiri Shigeyoshi
Published: July 2006

The non-empirical calculations of CH4 and SiH4 are carried out by the bond orbital (BO) and McWeeny and Ohno (MBO) methods. The lowest total energies obtained in these calculations are −40.1621 and −290.1809 a.u. for CH4 and SiH4 respectively. The ordinary SC–LCAO–MO calculations are also made for the sake of comparison using the same parameters. The results are compared with the similar calculations of H2O and NH3, we can thus see that the BO and MBO calculations show almost the same features as in H2O and NH3.
Peptide Synthesis via N-Acylated Aziridinone. II. The Reaction of N-Acylated Aziridinone and Its Use in Peptide Synthesis
Authors: Miyoshi Muneji
Published: July 2006

Optically active N-acylated aziridinone, which was synthesized by the dehydration of the corresponding l-acylamino acid, was treated with various nucleophiles, such as alcohol, amine, and water. The ring fission of the aziridinone took place exclusively at the carbonyl-nitrogen bond to give l-acylamino acid derivatives. The reaction was used successfully in the peptide synthesis, using an amino acid ester as a nucleophile. A retention of the optical activity was observed throughout the reaction.
The Reactions of 2-Hydroxybenzophenones with Lead Tetraacetate and Manganic Acetate
Authors: Kurosawa Kazu , Sasaki Yasuko , Ikeda Mikio
Published: July 2006

2-Hydroxy-4-methoxy- and 2-hydroxy-4,4′-dimethoxybenzophenones were oxidized to dimeric compounds with lead tetraacetate and with manganic acetate. 2-Hydroxy-2′,4,4′-trimethoxy- and 2-hydroxy-3′,4,4′trimethoxybenzophenones were oxidized to substituted xanthones. The structures of the products were determined by NMR and mass spectra, and were confirmed by syntheses.
Aminosugars. XXI. Conformation of Cyclic Imido Groups Attached to the Glucopyranose-ring
Authors: Iwakawa Masaharu , Yoshimura Juji
Published: July 2006

Conformation of cyclic imido groups at different positions on O-acetylated-d-glucopyranose-ring was examined from the anisotropic effect of the carbonyls on vicinal ring-protons. The imide-plane at β-C1, C3 were deduced to be slightly inclined counter-clockwise, from the right angle to the mean plane of the pyranose ring, and that at α-C2 and C4 clockwise. 3-Deoxy-1,2 ; 5,6-di-O-isopropylidene-3-phthalimido-α-d-gluco- and -allofuranose were also examined.
Mössbauer Study of the Thermal Decomposition Products of SrFeO4
Authors: Ichida Toshio
Published: July 2006

The thermal decomposition products of SrFeO4 were studied by 57Fe-Mössbauer-effect and X-ray-diffraction measurements. Below 300°C in air, an amorphous Fe3+ product was formed. The Fe4+ or Fe5+ state was not observed in the process. A single-phase product with a perovskite structure was obtained in air at temperatures above 400°C. The products obtained between 400 and 650°C showed cubic symmetry, but above 700°C they showed tetragonal distortion. Two kinds of Fe3+-ion sites were detected in the tetragonal SrFeOx. compounds. All the products obtained under the oxygen pressures from 50 to 500 atm and at temperatures from 300 to 900°C showed cubic symmetry. The Fe3+/Fe4+ ratio in those products was determined from the relative intensities of the Mössbauer absorptions.
Infrared Study of Carbon Dioxide Adsorbed on Magnesium and Calcium Oxides
Authors: Fukuda Yasuo , Tanabe Kozo
Published: July 2006

The infrared absorption spectra of CO2 adsorbed on MgO and GaO were measured in the wide region 700–4000 cm−1 at various amounts of adsorbed CO2 and temperatures of adsorption and desorption. It has been found that both uni- and bidentate carbonates are formed on MgO when a small amount of CO2 is adsorbed and that unidentate carbonates predominate as the amount of adsorbed CO2 is increased. On the other hand, only unidentate species were formed on CaO at room temperature independently of the amount of adsorbed CO2, but bidentate species were also formed on CaO when the temperature of adsorption was high. The unidentate carbonates formed on both MgO and CaO at room temperature partially changed to bidentate carbonates upon evacuation at higher temperatures. The correlation between Δv=|v1–v5| and the partial charge on oxygen atoms of various oxides, which corresponds to basic strength on the surface, was examined.
Studies on Actinoid Elements. V. The Determination of the Np(V)/Np(IV) Ratio in an Aqueous Solution by Means of the Partition Method
Authors: Ohyoshi Akira , Kawamura Tsuneo
Published: July 2006

The distribution study of neptunium ions in an aqueous solution containing Np(IV) and Np(V) was made using the metal chelate extraction system, TTA-benzene, or HDEHP-benzene at room temperature. The results obtained by this method were then compared with those obtained by spectrophotometry. In each system, a linear relationship was obtained between the fraction of the Np(V) ion and 1/(D+1), where D is the distribution ratio of neptunium. This analysis was performed with an accuracy of ±5% and was established within one minute in the case of the HDEHP-benzene system. The results obtained by this method were in good agreement with those obtained by spectrophotometry.
Studies of the Surface of Rutile Single Crystals by Means of Electrical Conductivity
Authors: Iwaki Toru
Published: July 2006

The surface properties of rutile single crystals were studied by the measurement of the d.c. electrical conductivity. Upon successive thermal treatments in vacuo from 25 to 550°C, the electrical conductivity on the (110) plane increased remarkable, while the activation energy decreased. The addition of oxygen decreased the conductivity according to the oxidation temperature, whereas the reduction by hydrogen above 300°C increased the conductivity greatly. The number of carriers was also determined from the measurement of the Hall effect. These results, by reference to those of the photoconductivity, were interpreted in terms of the change in the energy band structure near the surface associated with the defect centers on the surface.
Dielectric Behavior of the Packing Bed of Alumina Granules with Adsorbed Water
Authors: Umeya Kaoru , Kanno Takashi
Published: July 2006

Dielectric behavior of the packing bed of alumina granules with various amounts of adsorbed water were determined in the frequency range 30 Hz–3 MHz. The dielectric relaxations characterized by a distribution in relaxation time were attributed to interfacial polarizations due to the adsorbed ions accumulated around the non-conductive points (i.e., discontinuous points on conducting paths consisting of water films adsorbed on alumina granules). Some of the adsorbed ions were carried away to the electrodes through the points of contact between the water films adsorbed on granules adjacent to each other (i.e., continuous conducting paths), giving rise to d.c. conductance and electrode polarization. When insulating sheets were inserted between the electrodes and surfaces of the packing bed, both the d.c. conductance and electrode polarization disappeared and another dielectric relaxation was observed. This was attributed to the interfacial polarization due to the ions accumulated at the interfaces between insulating sheets and water adsorbed on alumina granules.
Potentiometric Studies of Cadmium- and Zinc-Halide Complexes in Acetonitrile
Authors: Aihara Makoto , Misumi Seizo
Published: July 2006

The overall formation constants of cadmium- and zinc-halide complexes in acetonitrile were determined by potentiometric titration using a saturated metal amalgam indicator electrode. The effect of ion-pair formation was taken into consideration to elucidate the free halide ion concentration in the experiments. The values of logβ3 and logβ4 for cadmium-halide complex were found to be: I−, 22.4 and 26.5; Br−, 25.3 and 29.8; Cl−, 29.2 and 34.0. The values for zinc-chloride complex were 20.1 and 23.4.
Derivatographic Studies on Transition Metal Complexes. IX. Thermal CN-Bridging Reaction of Double Complex Salts in Solid Phase
Authors: Tsuchiya Ryokichi , Nakagawa Shigeo , Uehara Akira , Kyuno Eishin
Published: July 2006

It was found by derivatography and spectral measurements that the double complex salts, [Co(H2O)2N4] [Co(CN)6]·nH2O, where N4 is 4NH3, two moles of ethylenediamine (en) or one mole of triethylenetetramine (trien), [Co(NH3)2trien][Co(CN)6]·2H2O, [Co(NH3)tepa][Co(CN)6].2H2O, where tepa is tetraethylenepent-amine, and [Co(H2O)2trien][Cr(CN)6]·2H2O underwent deaquation-or deammonation-CN-bridging formation reaction upon heating. The general tendency was observed to be as follows: the more stable the structural configuration of the coordination sphere, the higher the activation energy. In the case of the complex containing hexacyanochromate(III) as an anion, the activation energy for the bridging formation reaction is especially high as a result of possible flipping in CN bridging groups.
Determination of Arsenic(III) by Anodic Stripping Method Using Co-deposition with Copper
Authors: Kuwabara Takeshi , Suzuki Shigetaka , Araki Shun
Published: July 2006

The determination of arsenic(III) by anodic stripping using co-deposition with copper was worked out. A 0.24 M hydrochloric acid containing arsenic(III) and copper(II) was electrolyzed with a rotating platinum electrode (rpm=800) at a constant current. The deposit on the electrode was stripped by linear potential sweep method in 4 M hydrochloric acid. The stripping voltammogram was recorded in the span voltage −0.2–+1.2 volt vs. SCE. The stripping voltammogram showed two peaks, at zero volt and 0.5 volt vs. SCE. The area of the second peak was proportional to the concentration of arsenic. Linear dynamic range was 1–20 microgram per milliliter. The method was rapid and simple, the time required for analysis being about 35 minutes (electrolysis temperature, 25°C). X-ray and electron diffractions indicate that the second peak in the stripping voltammogram results from the dissolution of Cu3As.
Methylene Analogs of Cyclobutenedione. VII. Photolysis of 2,3-Bis-(diphenylmethylene)cyclobutanone and Its Derivatives
Authors: Toda Fumio , Nakaoka Hisao , Yuwane Kentaro , Todo Eishiro
Published: July 2006

Photolysis of 2,2-dimethoxy-3,4-bis(diphenylmethylene)cyclobutanone (I), 2,3-bis(diphenylmethylene)cyclobutanone (XIV), and 3,4-bis(diphenylmethylene)cyclobutanedione (XXV) in methanol was investigated. Photolysis of I afforded tricyclic compound(II) and dimethyl cyclobutanedicarboxylate (III) in 48 and 35% yields, respectively. Photolysis of XIV and XXV afforded the dihydronaphthalene derivatives (XIX) (88% yield) and XXIV (72% yield), respectively. The mechanisms of these reactions were also studied.
Mechanism of Oxygen Exchange Reaction of Diaryl and Alkyl Aryl Sulfoxides in Sulfuric Acid
Authors: Kunieda Norio , Oae Shigeru
Published: July 2006

The mechanistic investigations of the concurrent oxygen exchange and racemization reactions of 18O-labeled and optically active methyl p-tolyl sulfoxide (I) and phenyl p-tolyl sulfoxide (II) in sulfuric acid of various concentrations have been carried out by the determination of detailed kinetics. The kinetic data were analyzed in the lights of kex⁄krac values, activation parameters, correlations between the rates and acidity functions, solvent isotope effects, polar effects of substituents, etc.. A gradual change of mechanism of the reaction from an SN2 type process to a predominant A-1 like one (in above 95% sulfuric acid) with the increase of the concentration of sulfuric acid was observed. All these observations suggest that the A-1 like reaction takes place through a cation radical (–\overset+·S–) or a dication (–\overset++S–) intermediate at higher concentrations of sulfuric acid, while the SN2 type reaction that involves a water molecule as nucleophile in the rate-limiting step is the predominant path in less concentrated sulfuric acid.
Polarographic Studies of Some Lanthanoids(III) in N,N-Dimethylacetamide
Authors: Aihara Makoto , Misumi Seizo
Published: July 2006

Polarographic behaviour of some lanthanoids(III) has been studied in N,N-dimethylacetamide. La(III), Pr(III), and Nd(III) showed irreversible, three-electron reduction wave and the other lanthanoids(III), Gd(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), and Lu(III) except Sm(III), Eu(III), and Yb(III), gave irreversible, three-electron reduction wave with a pre-wave. The kinetic parameters for La(III), Pr(III), and Nd(III) were determined by means of Koutecky’s method. Sm(III), Eu(III), and Yb(III) showed two-step reduction waves, the first wave being a reversible, one-electron reduction wave. These solvated lanthanoids(III) were investigated also by cyclic voltammetry.
Phenanthro[4,5-bcd]furan Derivatives. I. A Synthesis of 5-Hydroxy-1-methoxyphenanthro[4,5-bcd]furan
Authors: Shimizu Takahachi , Horaguchi Takaaki , Watanabe Akio
Published: July 2006

5-Hydroxy-1-methoxyphenanthro[4,5-bcd]furan(I;R=MeO) was synthesized by dehydrogenation with 20% palladium on charcoal from 5,6,7,7a,8,9-hexahydro-1-methoxy-5-oxophenanthro[4,5-bcd]furan(XVII), which had itself been prepared via a naphthofuran derivative (XVI) starting from 5,8-dimethoxy-1-tetralone (VII).
Racemization Reactions of Cobalt(III) Complexes of Ethylenediaminetetraacetate and Trimethylenediaminetetraacetate
Authors: Ogino Hiroshi , Takahashi Masatake , Tanaka Nobuyuki
Published: July 2006

The kinetics of racemization reactions of ethylenediaminetetraacetatocobaltate(III), CoIIIedta−, and trimethylenediaminetetraacetatocobaltate(III), CoIIItrdta−, were investigated in acid solutions. The rate law for the racemization of (+)546CoIIIedta− is:

\fracd[(+)546CoIIIedta−]dt=−2\frackr1Ka+kr2[H+]Ka+[H+][(+)546CoIIIedta−]

where Ka is the equilibrium constant of the reaction:

(+)546CoIII(H2O)Hedta\ightleftarrows(+)546CoIIIedta−+H+

The values of kr1 and kr2 at 120°C and at an ionic strength of 0.53 are 2.0×10−5 sec−1 and 5.6×10−4 sec−1 respectively. The rate law for the racemization of (+)589CoIIItrdta− is:

\fracd[(+)589CoIIItrdta−]dt=−2k′r2[H+][(+)589CoIIItrdta−]

The value of k′r2 at 120°C and at an ionic strength of 0.53 is 1.9×10−5 l mol−1 sec−1. It is known that the rate of the racemization reaction of optically-active CoIIedta2− is accelerated by the presence of CoIIedta2− because of the electron-exchange reaction between these two species. In this paper, the electron-exchange reaction between CoIIItrdta− and CoIItrdta2− is also investigated by the utilization of the optical activity. This reaction proceeds faster than the reaction between CoIIIedta− and CoIIedta2−.
One-Electron Reduction of Carbonium Ions. IV. A Kinetic Study on the Reduction of the Substituted Tropylium Ions with Cr(II)
Authors: Okamoto Kunio , Komatsu Koichi , Murai Osamu , Sakaguchi Osamu , Matsui Yoshihisa
Published: July 2006

The one-electron reduction of the unsubstituted, methyl-, ethyl-, isopropyl-, t-butyl-, triphenylmethyl-, and phenyltropylium ions with Cr(II) in a 10% HCl solution gives, quantitatively, the dimer of the corresponding substituted tropyl radical. The measurements of the reaction rate at 25°C exhibit this order of reactivity: t-butyltropylium (k2=7.98 l/g·ion·sec), isopropyltropylium (8.22), ethyltropylium (10.3), methyltropylium (11.1), tropylium (74.0), phenyltropylium (144), and triphenylmethyltropylium (567) ions. The values of log k2 have a linear correlation with the transition energies of the charge-transfer bands observed for these carbonium ions with pyrene, and also with the polarographic half-wave potentials of the respective cations. These correlations indicate that the reactivity of the carbonium ion in the reduction with Cr(II) is determined mainly by the electron affinity inherent in the respective cations. The values of log k2 also have a good linear correlation with the pKR+ values, implying a parallelism between the electron affinity and the electrophilicity of these stable carbonium ions.
The Tautomeric Equilibria of 4-(Dialkylamino)azobenzene Derivatives
Authors: Yamamoto Shunzo , Nishimura Norio , Hasegawa Shigeo
Published: July 2006

The tautomeric equilibrium constants, Kt=[ammonium ion]/[azonium ion], of the first conjugate acids of 4-dialkylaminoazobenzene derivatives were estimated by the spectrophotometric method. The Kt values increase in this order: pyrrolidino- <dimethylamino- <diethylaminoazobenzenes. The effects of N-alkyl groups on the base strength of the amino and azo nitrogens were examined in order to explain the effects on the tautomeric equilibrium. The base strength of azo nitrogens is governed by the degree of the resonance interaction between the amino group and the rest of the molecule. For dimethylamino- and pyrrolidinoazobenzenes, the base strength of the amino nitrogen can also be explained in terms of the resonance effects, but the amino nitrogen of diethylaminoazobenzenes exhibits an anomalously high base strength, arising from the steric inhibition of the hydrogen bonding in the free base. The above order of Kt can be explained in terms of these cumulative resonance and steric effects.
Polyether-amides from the Condensation of ω-(p-Carboxyphenoxy)alkanoic Acids with Aliphatic Diamines
Authors: Kito Taketoshi , Fujimoto Tsutomu , Mikami Ryuzo , Hirao Ichiro
Published: July 2006

Polyether-amides were prepared by the polycondensation of ω-(p-carboxyphenoxy)alkanoic acids (CPAA) and such aliphatic diamines as ethylenediamine, hexamethylenediamine, and piperazine. The polymers with higher intrinsic viscosities and moderate melting temperatures (200–240°C) were obtained from CPAA and hexamethylenediamine. The polymers from both CPAA and ethylenediamine or piperazine generally have low intrinsic viscosities; the former melted at higher temperatures than did the polyether-amides with hexamethylenediamine, while the latter melted at lower ones.
Syntheses of Isoprenoids by Telomerizations. VIII. Anionic Telomerizations of Isoprene with Secondary Amines
Authors: Takabe Kunihiko , Katagiri Takao , Tanaka Juntaro
Published: July 2006

The anionic telomerizations of isoprene with secondary amines in the presence of alkali-metal catalysts were investigated under several conditions. The n=2 telomers were found to contain N,N-dialkyl(3,7-dimethyl-2,6-octadienyl)amine (2A) and N,N-dialkyl(2-isopropenyl-5-methyl-4-hexenyl)amine (2B) as the main components, n=1 and n=3 telomers were also identified. On the basis of these results, the mechanism of this anionic telomerization and the reactivity of the carbanions connected with this reaction were discussed.
Bond Distortions and Related Phenomena in Peri-Condensed Tetracyclic Nonbenzenoid Aromatic Hydrocarbons
Authors: Toyota Azumao , Nakajima Takeshi
Published: July 2006

On the basis of the second-order Jahn-Teller effect and SCF MO method, we have examined the geometrical structures with respect to bond length and the ground-state multiplicity and stability of peri-condensed tetracyclic nonbenzenoid aromatic hydrocarbons. It was found that of the molecules examined, dibenzo[cd, gh]pentalene (III) and its seven-membered analogue (IV) should have a triplet ground-state, exhibiting no appreciable double-bond fixation in the peripheral carbon skeleton. The other molecules were predicted to suffer the first-order or second-order bond distortions, showing a more or less marked double-bond fixation. The electronic spectra were calculated using the bond distances obtained on the basis of SCF MO method.
Photochemical Reactions of Aromatic Compounds. XI The Photochemical Cycloaddition of Vinyl Ethers to α-Naphthonitrile
Authors: Pac Chyongjin , Sugioka Taizo , Mizuno Kazuhiko , Sakurai Hiroshi
Published: July 2006

The photochemical reactions of α-naphthonitrile with vinyl ethers gave two stereo-isomeric (2+2) cycloadducts, trans-1-cyano-8-alkoxy-2,3-benzobicyclo[4.2.0]octa-2,4-diene 1 and the cis isomer, 2, in 80–90% yields. From the results of fluorescence measurements and kinetic analysis, the photocycloaddition was established to occur from the lowest excited singlet state of α-naphthonitrile.
The Liquid Membranes of the Thiocyanate Ion-Sensitive Electrode
Authors: Ishibashi Nobuhiko , Kina Kenyu
Published: July 2006

Ion-selective electrode membranes responsive to the thiocyanate ion were prepared by using ion-association extraction systems. A crystal violet or tetraphenylarsonium cation was used as an ion exchange-site in the liquid nitrobenzene membrane. The liquid membrane electrode exhibits an ideal Nernstian response to the thiocyanate ion down to 10−5  M. The selectivity of the liquid membrane largely depends on the extractability of the diverse anion into nitrobenzene. The order of the selectivity coefficients, Kj, is as follows:

ClO_4^->IO_4^->SCN^->I^->ClO_3^->NO_3^->Br^->BrO_3^->Cl^-

High selectivities for thiocyanate over SO42−, H2PO4−, Cl−, BrO3−, and Br were observed. The membrane potential is independent of the pH variation in the region from pH 2 to 12.
The Polymerization of Vinyl Monomers in the Presence of Surface Active Agents. III. The Rate of the Polymerization of Styrene
Authors: Asahara Teruzo , Sen\={o} Manabu , Shiraishi Shinsaku , Arita Yoshikazu
Published: July 2006

Styrene polymerized in the presence of sodium tetrapropylenebenzenesulfonate in an aqueous system without any ordinary initiators. The rate of the polymerization was dependent on the concentration of the surfactant and on the initial monomer concentration. The apparent activation energy of the polymerization was about 13.9 kcal/mol. The polymerization was inhibited by adding hydroquinone to the reaction system.
Studies on the Synthesis of Furan Compounds. XXX. Syntheses and Steric Configurations of 3-(5-Nitro-2-furyl)-2-(5-bromo-2-furyl)acrylic Acid and Its Related Compounds
Authors: Hirao Ichiro , Kato Yasuhiko , Kozakura Shiro
Published: July 2006

cis- and trans- 3-(5-Nitro-2-furyl)-2-(5-bromo-2-furyl)acrylic acids (II and III) and their functional derivatives have been synthesized in connection with the syntheses and steric configurations of 3-(5-nitro-2-furyl)-2-(5-bromo-2-furyl)acrylonitrile and its related compounds. The treatment of cis-3-(5-nitro-2-furyl)-2-(2-furyl)-acrylic acid (I) with bromine in refluxing carbon tetrachloride afforded a 1 : 1 mixture of II and III in quantitative yield. II and III afforded methyl (IV and VI) and ethyl (V and VII) esters, via each acid chloride (VIII or IX) by treatment with methanol and ethanol, respectively. Similarly, cis- and trans-3-(5-nitro-2-furyl)-2-(5-bromo-2-furyl)acrylamides (X and XI) were obtained by treatment of VIII and IX with dry ammonia in benzene. Isomerization was observed in the conversion of X into trans-3-(5-nitro-2-furyl)-2-(5-bromo-2-furyl)acrylonitrile (XII) upon treatment with phosphoryl chloride, while XI maintained its configuration under similar conditions to afford XII. On the other hand, cis-acid and esters (II, IV, and V) were converted into the corresponding trans isomers (III, VI, and VII) respectively, by treatment with hydrazine hydrate in refluxing methanol. II was confirmed to be isomerized to III by heating with hydrochloric acid or by irradiation with ultraviolet light (406 mμ). The structures and configurations of these compounds were discussed on the basis of their IR and NMR spectra.
Studies of the Molybdenum Catalysts. Part I. Changes in the State of the Hydrated Molybdenum Oxide Catalyst during a Reaction between Thiophene and Hydrogen
Authors: Sotani Noriyuki , Hasegawa Masatomo
Published: July 2006

The reaction between thiophene and hydrogen on hydrated molybdenum oxide was studied. Structural and compositional changes in the catalyst were found during the hydrodesulfurization of thiophene. The main products of the reaction were n-butane, butenes, and hydrogen sulfide. The conversion of thiophene increased with the progress of the reaction and reached a steady value after passing through a maximum. This reaction process was distinguished into two stages. One is the “aging stage,” and the other is the “stationary stage.” At the aging stage, three reactions, that is: i) dehydration, ii) reduction, and iii) sulfurization occur. The catalyst reacts with the reactants and changes in structure and composition. Hydrated molybdenum oxide was converted to MoO3 by liberating the structural water, and MoO3 was reduced to MoO2. A part of the MoO3 was also sulfurized directly with thiophene to MoS2 during the aging stage, but MoO2 could not easily be sulfurized. At the stationary stage, no further change in the catalyst was found, and only the catalytic hydrodesulfurization of thiophene occurred. The conversion at the stationary stage, when the aging temperature was low, was larger than the conversion at a high temperature. The difference between the conversions at different reaction temperatures was assumed to result from the structural and compositional changes in the catalyst caused by the different temperatures of the aging processes. In this reaction, the dehydration at the aging stage controls the activity of the catalyst.
Photochemical Reactions of Enamino Ketones
Authors: Yamada Kazutoshi , Konakahara Takeo , Iida Hirotada
Published: July 2006

Photochemical reactions of N-aryl enamino ketones including one enone system and one divinylamine system in the molecule were examined. Photochemical behaviours of N-aryl enamino ketones differed for the tertiary and secondary amines involved. While 5,5-dimethyl-3-(N-methylanilino)cyclohex-2-en-1-one gave an oxidative cyclization product, 3-anilino-5,5-dimethyl-cyclohex-2-en-1-one gave two major products and a minor one. One of the major products was characterized as 3,3-dimethyl-5-hydroxy-3,4-dihydro-1-benzazocines by their elemental analyses and spectroscopic properties. The compounds showed 6π system pseudo aromaticity in their NMR spectra. The temperature-dependent NMR signals for gem-dimethyl protons were due to the flapping of the 8-membered ring. The reduction product with diborane was identified as 1,2,3,4,5,6-hexahydro-1-benzazocine by comparison with an authentic sample. The other major product was a ketene adduct and the minor product, a lactone.
The Prins Reaction of Cyclooctene and Cyclododecene
Authors: Uchida Akira , Maeda Toyohiro , Matsuda Sumio
Published: July 2006

The reaction products of the sulfuric acid-catalyzed condensation of cyclooctene or cyclododecene with formaldehyde in acetic acid at 40 °C were investigated. The reaction of cyclooctene gave a mixture of 4,5-hexa-methylene-1,3-dioxane, 2-cyclooctenylmethyl acetate, and 1-acetoxy-2-acetoxymethylcyclooctane, while reaction of cyclododecene gave a mixture of cyclic ethers; one was identified as 3-oxabicyclo[10,3,0]-6-pentadecene, and the others were estimated to be 15-acetoxy-3-oxabicyclo[9,3,1]pentadecane and 12,17-dioxatricyclo[13,3, 0,010,14]-2-octadecene.
Effects of N-Acyl- and N-s-Triazinyl Groups on the Rearrangement of S-(s-Triazinyl)-2-aminothiophenols and O-(s-Triazinyl)-2-aminophenols
Authors: Shiojima Takeo , Kuroda Toshio , Ohkawa Sohei , Hasegawa Yasushi , Matsui Kohji
Published: July 2006

S-s-Triazinyl-2-aminothiophenols (I) containing methoxyl and/or dimethylamino groups in the S-triazine nucleus gave disulfides of N-s-triazinyl-2-aminothiophenols upon the S→N migration of the s-triazinyl group in the presence of acid; the rate of S→N migration was slow compared to that of the O→N migration of the corresponding O-s-triazinyl-2-aminophenol. On acylation or s-triazinylation, S-dimethoxy-s-triazinyl-2-aminothiophenol (I–1) and O-dimethoxy-s-triazinyl-2-aminophenol (II-1) gave N-acyl-N-s-triazinyl- or N,N-bis (s-triazinyl) derivatives upon the S→N or O→N migration of the s-triazinyl group. However, S-dimethylaminomethoxy-s-triazinyl-2-aminothiophenol (I–2), S-bis[(dimethylamino)-s-triazinyl]-2-aminothiophenol (I–3) and the corresponding derivatives of o-aminophenol gave N-acyl- or N-s-triazinyl derivatives, wihtout any migration of the s-triazinyl group, by acylation or s-triazinylation. The facility of the rearrangement of these N,S-bis-(s-triazinyl)-2-aminothiophenols and N,O-bis(s-triazinyl)-2-aminophenols depended not only upon the substituents in S- or O-s-triazine nucleus, but also upon the substituents in the N-s-triazine nucleus; the substituents in the N-s-triazine nucleus of strong electron-attracting and of strong electron-donating substances were not appropriate for the rearrangement in the presence of alkali to give disulfides of N-s-triazinyl-2-aminothiophenols (III–I) or N-s-triazinyl-2-aminophenols (III–II).
Chemical Evidence for the Existence of pπ-dπ Interaction between the Unsaturated Bond and the Sulfur Atom in Allyl and Vinyl Sulfide Systems
Authors: Ojima Iwao , Kondo Kiyosi
Published: July 2006

Chemical evidence for the activation of double bonds by the use of 3d orbitals of the sulfur atom was observed in the reaction of allyl benzyl sulfide and phenyl vinyl sulfide with diazomethane. Similar supporting evidence was also obtained in the reaction of acetophenone tosylhydrazone with allyl benzyl sulfide in the presence of sodium methoxide at 150 °C. It was found that there should not be any important role of the oxygen atom of allyl benzyl ether in directing the orientation of the 1,3-dipolarophile.
Intramolecular Interaction between the Hydroxyl Group and the Oxirane Ring
Authors: \={O}ki Michinori , Murayama Tetsuo
Published: July 2006

The intramolecular interaction between the hydroxyl group and the oxirane ring has been detected by means of studying the infrared spectra in the 3μ region of various hydroxyalkyloxiranes. The O–H stretching absorptions of several compounds which have limiting structures in the sence of the conformational preference have been closely examined. The results indicate that the intramolecular interaction takes place between the hydroxyl group and the electron orbitals involved in the formation of the C–O bond, while that involving the electrons of the C–C bond can be neglected.
Macro Rings. V. Syntheses of Tetraoxaparacyclophanes Containing Two Biphenyl Nuclei
Authors: Nishikido Joji , Inazu Takahiko , Yoshino Tamotsu
Published: July 2006

Three new tetraoxaparacyclophanes containing two biphenyl nuclei connected with oxypolymethyleneoxy bridges in the respective 4,4′-positions, such as 1,5,18,22-tetraoxa[5.0.5.0]paracyclophane I3, 1,6,19,24-tetraoxa-[6.0.6.0]paracyclophane I4, and 1,7,20,26-tetraoxa[7.0.7.0]paracyclophane I5, were synthesized. The UV, IR, and NMR spectra of these paracyclophanes were compared with those of the corresponding open-chain compound, IV3.
Syntheses of l-Threose and Methyl Di-O-acetyl-l-threuronate from dextro-Tartaric Acid
Authors: Nakaminami Gen , Edo Haruo , Nakagawa Masazumi
Published: July 2006

Reduction of methyl hydrogen di-O-acetyl-dextro-tartrate (I) with sodium borohydride in water afforded l-threono-γ-lactone (II). l-Threose (IV) was obtained on treatment of the γ-lactone (II) with an excess of disiamylborane. Reduction of ester chloride of di-O-acetyl-dextro-tartaric acid (VI) with tri-n-butyltin hydride yielded methyl di-O-acetyl-l-threuronate (VII). Attempts to reduce 2-deoxy-pentarate ester (X) derived from ester chloride (VI) via diazoketone (VIII) with sodium borohydride to give 2-deoxy-threo-pentono-γ-lactone (XI) gave unsatisfactory results. Formation of methyl l-threo-2,3-di-O-acetyl-5-chloro-5-deoxy-4-C-hydroxymethyl-4,4′-anhydropentonate (IX) in addition to diazoketone (VIII) was observed when ester chloride (VI) was treated with an excess of diazomethane. On the basis of the observed (−)-Cotton effect in the 290 nm region of ORD and CD spectra of l-threose (IV) and d-erythrose, possibility of the presence of an open chain non-hydrated alde-hyde-form of aldotetrose in water was discussed.
The Peracid-oxidation of Tetraphenylallene: The Formation of Hydroxyindanone and Its Oxidative Transformation
Authors: Oku Akira , Shimada Kojiro , Mashio Fujio
Published: July 2006

The oxidation of tetraphenylallene (1) with m-chloroperbenzoic acid has been reported. Under acidic conditions, 1-hydroxy-1,3,3-triphenyl-2-indanone (2) was isolated in 45% yield, along with benzophenone (3) and the m-chlorobenzoate of 2 as minor products. In the presence of sodium carbonate, the oxidation products were 2,2,4,4-tetraphenyloxetanone (6), 3, and 1,3,3-triphenyl-2,3-dihydro-5H-indene-2,5-dione (5). The prolonged oxidation of 2 with per ace tic acid yielded α,α-diphenylphthalide (9a). The alkaline hydrolysis of 2 induced ring cleavage to give o-benzhydrylbenzilic acid (15b), whereas acid hydrolysis in ethanol or methanol gave the corresponding ethers, 16a and 16b respectively.
Selective Homogeneous Hydrogenation of 3-Oxo-1,4-diene Steroids. II. Effects of Basic Additives and of para Substituents on the Hydrogenation with Dichlorotris(triphenylphosphine)ruthenium
Authors: Nishimura Shigeo , Ichino Tomio , Akimoto Akira , Tsuneda Kiyoshi
Published: July 2006

The catalytic homogeneous hydrogenation of 1,4-androstadiene-3,17-dione (I) with dichlorotris(triphenylphosphine) ruthenium has been investigated in the presence of basic additives. The rate of hydrogenation increased with respect to added amines in the order pyridine<none<butylamine<aniline<diethylamine≅triethylamine. The hydrogenation was also promoted by the addition of calcium carbonate, but slightly retarded by that of sodium carbonate. The amount of triethylamine required for obtaining the maximum rate of hydrogenation has been determined. Addition of triethylamine also reduced the formation of 5α-androstane-3,17-dione produced by a different pathway from that for the formation of 4-androstene-3,17-dione (II), resulting in an increased selectivity for the formation of II. I was also hydrogenated with the ruthenium complexes having p-methoxy-, p-methyl-, and p-fluoro-substituted triphenylphosphines as ligands. The catalytic activity of the ruthenium complex was greatly enhanced by p-methoxyl and p-methyl groups and reduced by p-fluoro group when the catalyst was used in the presence of triethylamine.
Studies of Enamines. II. The Reaction of 4-(1-Piperidyl)- and 4-(1-Pyrrolidinyl)-3-penten-2-ones with Aryl Isocyanates
Authors: Tsuge Otohiko , Inaba Akitaka
Published: July 2006

The reaction of aryl isocyanates with enamino ketones, derived from acetylacetone and secondary amines such as piperidine and pyrrolidine, has been investigated. At room temperature, enamino ketones react with phenyl, p-chlorophenyl and p-tolyl isocyanate to give 1:2 adducts, 3,5-diarylcarbamoyl derivative. In solution, these adducts exist in general as a mixture of two tautomers, 3-penten-2-one and 4-penten-2-one, the ratio depending on the solvent. Under reflux in benzene, the reaction of enamino ketones with phenyl isocyanate gives 4-amino-6-methyl-1-phenyl-5-phenylcarbamoylpyrid-2-one and its 3-phenylcarbamoyl derivative; the former is also obtained by heating the 1:2 adduct. On the other hand, 4-(1-pyrrolidinyl)-3-penten-2-one reacts with 1-naphthyl isocyanate to afford the 1:1 adduct, 5-(1-naphthylcarbamoyl)-4-penten-2-one.
Preparation of p-Nitrophenyl 2-O-Acetyl-β-d-glucopyranoside and N-Acetyl-β-d-glucosaminidase Activity toward It. (Essential Requirement of 2-Acetamide Group of Substrate for N-Acetyl-β-d-glucosaminidase Hydrolysis)
Authors: Yamamoto Kazuhiko
Published: July 2006

Paranitrophenyl 2-O-acetyl, and 2,3-di-O-acetyl-β-d-glucopyranoside (VI, VII) were synthesized in order to investigate the effect of the substitution of the amide-nitrogen of the substrate by oxygen on the N-acetyl-β-d-glucosaminidase hydrolysis. Paramethoxybenzylidene was used as an O-blocking group for the preparation, and it was found that this blocking group could be easilly removed without the destruction of p-nitrophenyl glycoside. The evidence that VI could not be hydrolysed with this enzyme indicated the essential requirement of the amide-nitrogen of the substrate for the enzyme action.
The ESR Study of the Interaction of O2 with Ag Dispersed on Silica Gel
Authors: Shimizu Natsuko , Shimokoshi Kazuo , Yasumori Iwao
Published: July 2006

The state of adsorbed oxygen on metallic silver dispersed on silica gel has been studied by ESR. The spectra observed by the interaction of oxygen and the surface were found to be composed of spectra due to two different species. One of the species, which was formed separately by the contact with oxygen at −110 °C, was identified with O2− chemisorbed on metallic silver by a comparison of the observed g values and the other features with those previously reported. The other species has a doublet at g=2.036. This spectrum was reproduced by the interaction of N2O with the silver surface. Further, the γ-irradiation of the silver samples in the presence of O2 and N2O markedly enhanced the intensity of this spectrum, showing a low-field hump. On the basis of the g values and the splitting of the high-field doublet, assuming that the doublet is due to the hyperfine interaction of an unpaired electron with the silver nucleus, the species was assigned to Ag2+ in the present system. It is postulated that this species is possibly formed by the dissociative and/or charge-transfer chemisorption of O2 and N2O, suggesting the presence of non-paramagnetic oxygen species, such as O2−, as a counter ion of Ag2+.
The Microwave Spectrum of Methyl Iodide in Excited Vibrational States. Fermi and Coriolis Interactions among v3+v6, v5, and v2 Vibrations
Authors: Kawashima Yoshiyuki , Hirose Chiaki
Published: July 2006

The J=2←1 transitions of methyl iodide in the v3, v6, 2v3, v2, v3+v6, and v5 vibrationally-excited states are observed. In v3+V6, the central component, ν360, of the J=2←1, K=1←1 transition is observed at 14.6 MHz, higher than the ν36+ of the l-type doubling. This is interpreted by the fact that the E state with K=−l=±1 is affected more strongly by the Fermi resonance through k356 than is the A state with K=l=±1. The Fermi resonance through k356 causes the Coriolis coupling between v2 and v5 through ζ25(y) to be transferred to v3+v6. As a result, the l-type doubling constant, q6, is determined to be −5.8 MHz. The Stark effect in the presence of the l-type doubling and nuclear quadrupole splitting is formulated and used in the analysis.
The Electronic Structure of Nickelocene by Means of the Configurational Interaction Method
Authors: Kobinata Shunsuke
Published: July 2006

The electronic structures of nickelocene have been investigated by means of the configurational interaction method. The locally-excited configurations of the central metal ion and the charge-transfer configurations corresponding to an electron transfer from the ligand system to the central metal ion have been taken into account. A correspondence with the crystal-field treatment has been obtained using the partitioning technique of solving the secular equation. The energies of the charge-transfer configurations, the resonance integrals, and the Racah parameters were determined so as to obtain the best fit with the observed d-d transition energies.
Oxygen Exchange between Arsenate Ions and Water of Crystallization in the Course of Hydration and Dehydration of Disodium Hydrogen Arsenate and Sodium Dihydrogen Arsenate
Authors: Okumura Akiko , Okazaki Nobukazu
Published: July 2006

Oxygen exchange between arsenate ions and crystal water in the course of hydration of anhydrous salt with water vapor and subsequent dehydration of the resulting hydrate has been studied with disodium hydrogen arsenate and with sodium dihydrogen arsenate. There is a remarkable difference in the exchange behavior between the anhydrous salt prepared by dehydration in vacuo at room temperature and that prepared at higher temperatures. In the former, the degree of exchange increases with increasing molar ratio of the reactants(arsenate to water), while in the latter, it is independent of the molar ratio. In the exchange reactions of the anhydrous salt prepared at higher temperatures, the number of exchangeable oxygen atoms of an arsenate ion is found to be 0.5 (that is, one atom for two arsenate ions) for disodium hydrogen arsenate, and 4 for sodium dihydrogen arsenate.
Studies on Nitrile Salts. II. A Facile One-step Synthesis of the Pyrimidine Nucleus
Authors: Yanagida Shozo , Fujita Tetsuo , Ohoka Masataka , Kumagai Reiji , Komori Saburo
Published: July 2006

The reaction of N-(α-chloroalkenyl)alkylamidine hydrochlorides (1) with phosgene was studied. The amidine hydrochlorides (1a—h) which were prepared from nitriles with more than two α-hydrogens reacted with phosgene at 100—105°C to give good yields of 4,6-dichloro-2,5-disubstituted-pyrimidines (3a—h). The amidine hydrochlorides (1j—t), which were obtained from nitriles with only one α-hydrogen, afforded 2-alkylidene-4,6-dichloro-5,5-disubstituted-2,5-dihydropyrimidines (5j—t) in good yields. The amidine hydrochloride 1i, however, gave 2-dichloromethylidene-2,5-dihydro-5,5,6-trichloro-4(3H)-pyrimidinone (4i) under comparable conditions.