Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
54 巻 , 1 号
選択された号の論文の76件中1~50を表示しています
  • Akira Katagiri, Kiyoshi Watanabe, Shiro Yoshizawa
    1981 年 54 巻 1 号 p. 1-4
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The reduction of sulfuric acid has been studied for the purpose of the regeneration of activated carbon, which is used as an acceptor of sulfur dioxide from exhaust gas. When activated carbon impregnated with sulfuric acid was heated in a hydrogen atmosphere, sulfuric acid was reduced to sulfur dioxide by carbon in the temperature range from 200 °C to 350 °C. When copper sulfate was added, the sulfuric acid was reduced to sulfur dioxide, mainly by hydrogen, in the temperature range from 190 °C to 270 °C. At 227 °C, for example, the rate of reduction by hydrogen was nine times greater than the rate of reduction by carbon. Copper sulfate was sufficiently effective in an amount of one-fifth of the sulfuric acid in moles, indicating that copper in some form participates in the catalytic reaction.
  • Akira Katagiri, Kiyoshi Watanabe, Shiro Yoshizawa
    1981 年 54 巻 1 号 p. 5-7
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The reduction of sulfuric acid, which is formed on the activated carbon catalyst in the course of removing sulfur dioxide from exhaust gas, was investigated. The platinum, palladium, silver, and copper on activated carbon were found to be catalytically active in the reduction of sulfuric acid by hydrogen, while manganese, iron, cobalt, nickel, and zinc were found to be inactive. The copper–carbon catalyst is favorable, because sulfuric acid was reduced selectively to sulfur dioxide on it at temperatures from 190 °C to 270 °C. On the platinum–carbon catalyst, the reduction occurred at a relatively low temperature (140 °C to 200 °C), but hydrogen sulfide and elemental sulfur were formed in addition to sulfur dioxide. It is concluded from thermodynamic calculations that catalytically active metals were in the metallic state on activated carbon under the present reaction conditions. An electrochemical mechanism is proposed for the reaction.
  • Izumi Maki, Kichisuke Nishimoto, Masa-aki Sugiyama, Hiroshi Hiratsuka, ...
    1981 年 54 巻 1 号 p. 8-12
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The polarization spectra of indole, 3-indolebutyric acid, and benzimidazole have been measured and analyzed by means of MO theory taking Σ-II interaction into consideration. Induced transition moment due to Σ-II interaction can be assigned to each σ-bond (both direction and magnitude) pictorially. The effect of hetero atom on the electronic absorption spectra can be interpreted reasonably. Agreement between experimental and calculated results is satisfactory.
  • Bu Yong Lee, Yasunobu Inoue, Iwao Yasumori
    1981 年 54 巻 1 号 p. 13-19
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The hydrogenation of cyclohexene vapor on dispersed palladium was studied in the pressure range of 10–40 Torr at temperatures between 283 and 323 K. Palladium was impregnated on ZrO2 and α-Al2O3 over the wide range of 0.03 to 2.1 wt%, and the percentage exposed was varied from 13 to 96% for Pd/ZrO2 and from 2 to 15% for Pd/α-Al2O3. The hydrogenation activity, Vg, per unit of weight of the Pd dispersed on ZrO2, exhibited a sharp maximum at 0.05 wt%, but the turn-over frequency, Vs, per exposed atom around this maximum remained almost constant, which shows the reaction to be structure-insensitive. The value of Vs for Pd/ZrO2 at 301 K was larger than those for Pd/α-Al2O3 and Pd bulk metal by one order of magnitude. The ZrO2 carrier affected the catalytic behavior of palladium; the reaction orders with respect to the hydrogen and cyclohexene pressures changed to 0.73±0.04 and 0.64±0.04 respectively from the corresponding values, 0.97±0.03 and 0.07±0.04 for Pd/α-Al2O3 and Pd metal. The deuterium distributions in the reactant and product molecules in the reaction with D2 suggested that the hydrogenation on Pd/ZrO2 and Pd/α-Al2O3 proceeds via the associative mechanism ; the slow step is assumed to be the reaction of the surface cyclohexyl radical with the adsorbed hydrogen atom. The poisoning due to preadsorbed CO decreased the catalytic activities of Pd/ZrO2 and Pd/α-Al2O3 almost linearly with the amounts of surface CO and caused a complete deactivation at about a half coverage of the surface Pd atoms, irrespective of the percentage exposed. On the basis of these results, the structure-insensitivity of the cyclohexene hydrogenation on Pd and the carrier effect of ZrO2 are discussed.
  • Masakatsu Yonese, Hideya Tsuge, Hiroshi Kishimoto
    1981 年 54 巻 1 号 p. 20-24
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The osmotic coefficients of a solvent, φ, in aqueous solutions of sodium chondroitin-4-sulfate (NaChS-A) with a relatively low molecular weight and -6-sulfate (NaChS-C) with various molecular weight were measured by means of vapor-pressure osmometry. The molar Gibbs energes of dilution, ΔdilG were determined from the thermodynamic analysis of the φ values. The molar entropies of dilution, ΔdilS were calculated through the substitution of the molar dilution enthalpies, ΔdilH which had been measured previously, into ΔdilG. These thermodynamic quantities of dilution were discussed by taking Manning’s limiting law into consideration. The concentration and temperature dependencies of the observed ΔdilH agreed well quantitatively with those of the electrostatic ΔdilH calculated by Manning’s limiting law, when the distance between the neighboring charges of the polyion, b, was assumed to be 4.8 Å, whereas the observed ΔdilG and ΔdilS values did not agree quantitatively with the theoretical ones based on electrostatic interactions. From a comparison of the experimental ΔdilS values with the theoretical ones, the non-electrostatic dilution entropy was evaluated and discussed.
  • Isao Kamiya, Takashi Sugimoto
    1981 年 54 巻 1 号 p. 25-30
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Direct chemiluminescence emissions have been found from the air oxidation of 3-acyl-9-methyl- (1), 3,6-diacyl-9-methyl- (2), and 9-acylcarbazoles (3) due to the generation of an excited singlet state of monocarboxylate ions (from 1 and 2) and the carbazole anion (from 3). The relative intensities vs. the reaction time for the luminescent reaction of 3-isobutyryl-9-methylcarbazole could be interpreted by a reaction scheme involving consecutive reactions. Using this reaction scheme, the values of the decomposition rate of intermediates at 30, 40, and 50 °C were determined to be 0.19, 0.42, and 0.98 min−1 respectively, which were comparable to the values reported for the decomposition rates of isolated dioxetanes giving excited singlet products.
  • Kiwamu Yamaoka, Sumihare Noji, Mamoru Yoshida
    1981 年 54 巻 1 号 p. 31-34
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The optical absorption spectra of several derivatives of Proflavine (PF) and Coriphosphine O (CP) were measured in aqueous solutions at 25 °C. The effect of the perturbation of one or both of the exonuclear amino groups on the spectral behavior was studied in order to explore the relationship between the spectra and the chemical structures of the symmetric 3,6-disubstituted acridine dyes which can bind to various polyelectrolytes, often showing metachromasy. The metachromatic spectra of the complexes between 3,6-diaminoacridine dyes and polyanions were reproduced reasonably well when one of the two amino groups of PF was converted to an acylamino group. A similar result was observed when the amino group of CP was acetylated. In these cases, the spectra show two absorption bands of nearly equal intensity on both sides of the single peak of PF and CP in the visible region. These results are indicative of the close similarity in chemical structures between the monacylamino PF and the PF bound to the electron-rich sites of polyanions.
  • Shinzaburo Ito, Masahide Yamamoto, Yasunori Nishijima
    1981 年 54 巻 1 号 p. 35-40
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Various dinaphthylalkanes in which two naphthyl groups are separated by three carbon atoms were prepared, and intramolecular excimer formation was investigated. All rate constants in Förster’s kinetics were determined by the steady state and time-resolved fluorescence measurements. A large difference in the association rate constant was observed with variation of molecular structure. The results suggest that intramolecular excimer formation is directly controlled by the rotational relaxation processes of the molecules from their neighboring conformations to the excimer conformation. A large formation rate (7.9×108 s−1 at 25 °C) was observed for meso-2,4-dinaphthylpentane, the rate for the racemo isomer being found to be one tenth of that for the meso isomer. This indicates that the isotactic sequence in vinyl aromatic polymers plays an important role in the intramolecular excimer formation.
  • Hiroshi Ayato, Isao Tanaka, Takashi Yamane, Tamaichi Ashida, Tadashi S ...
    1981 年 54 巻 1 号 p. 41-44
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The molecular structures of 3-methylthio-2-rnethyl-5,6-diphenyl-2,5-dihydro-1,2,4-triazine (1) and its reaction product with dimethyl acetylenedicarboxylate, 5,6-bis(methoxycarbonyl)-2-methyl-1-methylthio-4,8-diphenyl-2,3,7-triazabicyclo[3.3.0]octa-3,6-diene (2), were determined by the X-ray method. The former belongs to the triclinic system P\bar1, with Z=2, a=10.776(2), b=10.203(2), c=8.556(1) Å, α=105.44(2), β=104.94(2), and γ=60.31(2)°; the latter belongs to the orthorhombic system Pca21 with Z=4, a=18.166(2), b=7.444(2), and c=16.080(2) Å. Both structures were solved by the direct method. The final R-factors are 0.075 for 1 and 0.048 for 2. In Compound 1 the dihydrotriazine ring is in the boat form, while in Compound 2 both of the cis-fused five-membered rings are in the envelope form.
  • Tetsuo Takaishi, Yujiro Kamei, Atsushi Yusa, Tatsuo Ohgushi
    1981 年 54 巻 1 号 p. 45-48
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The isobaric gas sorption with (Na,Ca)–A and (K,Ca)–A zeolites was measured gravimetrically in temperature ranges of −160–−40 °C for O2 and N2, and of room temperature—200 °C for n-C4H10. The sorption hysteresis, i.e., the gas encapsulation was observed. The maximum point, in the temperature rising branch of the isobar, was located at about −90 °C for N2 and in the range 120–170 °C for n-C4H10, and shifted to the lower temperature side with the increasing content of calcium for n-C4H10. The observed results are explained in terms of an incomplete blocking action of cations on window sites. This incompleteness was amplified by bivalent cations introduced onto other sites than the window sites, and the sieving character of the ion-exchanged zeolite was delicately modified.
  • Akio Furusaki, Shinsei Gasa, Ry\={u}z\={o} Ikeda, Takeshi Matsumoto
    1981 年 54 巻 1 号 p. 49-54
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The molecular structure of grayanotoxin XVI, C22H34O6, has been confirmed by means of an X-ray crystal analysis of its hemihydrate. The crystals are orthorhombic, with eight formula units in a unit cell with dimensions of a=17.503, b=37.933, and c=6.371 Å; the space group is P212121. 4180 unique intensity data were collected on a four-circle diffractometer with LiF-monochromated Cu Kα radiation. The structure was solved by the Monte Carlo direct method, using the 30 strongest reflections as the starting set, and was refined by the block-diagonal least-squares method. The final R value was 5.5%. The present analysis has revealed that the crystal used comprises about four parts of grayanotoxin XVI (6-O-acetylgrayanotoxin II) and one part of 10,20-dihydrograyanotoxin XVI. The molecules of the major component exist in two different conformations: One has the chair B-ring, and the other the twist-chair B-ring. About two-fifths of the molecules of the latter type are replaced at random by the molecules of the minor component.
  • Takashi Kitamura, Shigeru Tsunashima, Shin Sato
    1981 年 54 巻 1 号 p. 55-59
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The photolysis of hydrogen azide was studied in liquid ethylene, propene, and the mixture with ethane at the temperature of Dry Ice–methanol. The products observed were aziridine (0.18), ammonia (0.16), and nitrogen (1.0) from the ethylene solution and 2-methylaziridine (0.33), allylamine (0.12), ammonia (0.17), and nitrogen (1.0) from the propene solution. The values in parentheses show the yields relative to that of nitrogen. The relative yields were independent of the concentration of hydrogen azide in the range of 0.8–8×10−2 mol dm−3. The reaction of NH(a1Δ) radicals with olefin consists of three processes: the addition to double bond, the insertion into the C–H bond, and the deactivation to the 3Σ state. The branching ratios and the relative rate constants of the reactions of NH(a1Δ) radicals with ethylene, propene, and ethane were estimated.
  • Yoshihumi Kusumoto, Hiroyasu Sato, Kazuto Maeno, Shuichi Yahiro, Nobua ...
    1981 年 54 巻 1 号 p. 60-64
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Lasing wavelengths and fluorescence spectra were measured for a mixed dye system containing various concentrations of Rhodamine 6G (Rh-6G) and 3,3′-dietriylthiacarbocyanine iodide (DTC), which have very closely located S1 levels, in acetone at room temperature. A new way of confirming the occurrence of energy transfer is presented on the basis of the reabsorption effect. It was found that most of the pump power absorbed by Rh-6G is transferred to DTC. A study of the fluorescence decay by a picosecond laser revealed that the energy transfer is essentially governed by the Förster mechanism. The observed fluorescence decay data agree fairly well with the R0 value of 73.2 Å calculated from the spectral overlap.
  • Yukio Sasaki, Masao Takizawa, Kisaburo Umemoto, Niro Matsuura
    1981 年 54 巻 1 号 p. 65-68
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The differences in the order of stability among halide ions for metal halogeno-complexes in nonaqueous solvents and water are examined by means of the thermodynamic constants for the formation of thallium halides of transfer from water to N,N-dimethylformamide (DMF) and propylene carbonate (PC). The thermodynamic constants for the formation of thallium halides were calculated from the solubility products of thallium halides. The differences in the order of stability for thallium halides were found to be dependent mainly on the enthalpy changes for the formation of thallium halides of transfer from water to DMF and PC, while the enthalpy changes of transfer for thallium halides are themselves largely influenced by the enthalpy changes for halide ions of transfer from water to DMF and PC.
  • Yasuyuki Yamada, Isao Tanaka, Tamaichi Ashida
    1981 年 54 巻 1 号 p. 69-72
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The crystal structure of the title compound was determined by the X-ray method. The space group is P21,with a=18.741(3), b=12.602(1), c=9.553(1) Å, β=118.46(2)°, and Z=4. The structure was determined successfully by the vector-space-search method, using a dimer structure of Boc–Pro–Val–Gly–OH as a rigid group. The final R value was 0.075 for 2025 non-zero reflections. Two independent molecules related by a pseudo twofold axis are linked by β-sheet-type hydrogen bonds. This kind of dimerization commonly occurs in all the Boc–Pro–X–Gly–OH peptides except Boc–Pro–Leu–Gly–OH. The packing similarity of these peptides is discussed.
  • Taro Tachibana, Tomoko Mori, Kayako Hori
    1981 年 54 巻 1 号 p. 73-80
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    A new type of chiral solid mesophase was obtained by evaporating the solvents from solutions or jellies of chiral 12-hydroxyoctadecanoic acid (12HOA). The mesomorphic solids exhibited some optical properties characteristic of a helicoidal mesophase: (1) spherulitic or Schlieren texture under a polarizing microscope, (2) reflective circular dichroic band, and (3) induced circular dichroic spectra with a single sign due to achiral molecules added to the solid. From the circular dichroic and X-ray studies, it was concluded that the helicoidal mesophase structure exists locally as small domains with a chiral smectic structure within the mesomorphic solids. Microscopic observation revealed that, upon heating, the transition of the mesomorphic solid to the crystalline solid occurred. This process was studied by differential scanning calorimetry. Formation of a variety of helicoidal systems from chiral molecules such as 12HOA and polypeptides was regarded as a phenomenon characteristic of chiral assemblies of amphiphilic molecules.
  • Takashi Takahashi, Yoshiya Harada
    1981 年 54 巻 1 号 p. 81-84
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The so lid phase ultraviolet photoelectron spectra of water, carbon disulfide, benzene, N-methylaniline, and pentane condensed on a gold substrate at 77 K were measured. The features of the spectra are similar to those of the corresponding gas phase spectra. The difference between the gas and solid phase IP’s, the relaxation shift, is nearly constant for each compound studied except for the case of water, where the 3a1 molecular orbital state in solid is affected by the hydrogen bonding. The values of the relaxation shift for water, benzene and carbon disulfide are 1.1–1.3eV, while those for N-methylaniline and pentane are 0.6 and 0.7 eV, respectively. The small values for the latter compounds are due to the fact that the molecules are loosely packed in the solids. The mechanisms of the band broadening for the molecular crystal are discussed in relation to the spectrum of solid carbon disulfide. For N-methylaniline the spectra of the gas, liquid and solid phases were compared. To our knowledge, this is the first case in which the electronic structures of all the three phases are studied by ultraviolet photoelectron spectroscopy.
  • Taketoshi Hideshima, Misao Morinaga, Hideo Kimizuka
    1981 年 54 巻 1 号 p. 85-89
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The static and kinetic feature of the reaction of sodium cyanide with 1-bromoalkanes in the presence of various phase transfer catalysts was investigated in the oil/water system by using a layered scintillation method and the mechanism of catalytic action was discussed. From the measurement of equilibrium constants for both reactions of hexadecyltrimethylammonium cyanide with 1-bromooctane and of sodium cyanide with hexadecyltrimethylammonium bromide in organic phase, it was pointed out that the latter reaction was responsible for the advance of overall reaction. It was also found that majority of the phase transfer catalysts exist in the oil phase. It was suggested that an uptake reaction of cyanide ion from the aqueous phase at the interface is essential and that the reaction process does not follow a simple model proposed by Starks et al.
  • Taizo Ono, Yoshio Sasada
    1981 年 54 巻 1 号 p. 90-93
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Copper(II) complex containing L-alanine and L-histidine crystallizes from aqueous solution at pH 7.0. Crystals of (L-alaninato)aqua(L-histidinato)copper(II) trihydrate are monoclinic, space group P21 a=10.980(4), b=7.362(3), c=9.700(2) Å, β=101.45(3)°, and Z=2. There is some disorder for the location of three water molecules of crystallization. Four coordinating atoms in an approximately planar arrangement around copper are the α-amino nitrogen and imidazole δ-nitrogen of L-histidine, and α-amino nitrogen and α-carboxyl oxygen of L-alanine. They take a cis conformation with respect to the amino groups. The axial site is occupied with oxygen atom of water, so that the coordination geometry is square-pyramidal. Similarity and difference are discussed in comparison with the coordination mode in copper complexes containing L-histidine and L-asparagine.
  • Tamaki Maeda, Makoto Ikeda, Mitsuhiro Shibahara, Takahide Haruta, Iwao ...
    1981 年 54 巻 1 号 p. 94-98
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Study was made of the potentiometric selectivities of poly(vinyl chloride) membrane with and without dibenzo-18-crown-6. It was found that these membrane electrodes were highly selective for cationic surfactant ions and showed a Nernstian response to surfactant ion such as 1-dodecylpyridinium ion even in the concentration range as low as 10−6 mol/dm3. The selectivity coefficients of inorganic cations, taken with respect to 1-dodecylpyridinium ion, were of the order of 10−5 or less, while that of surfactant ion was found to depend not only on hydrophobic alkyl chain length but also on the type of hydrophilic head group. For cationic surfactants with the same hydrocarbon chain length, the membrane without crown ether exhibited the order of selectivity: 1-alkylpyridinium ion>alkyltrimethylammonium ion>alkylammonium ion. In the case of the membrane with crown ether, the selectivity sequence became alkylammonium ion>1-alkylpy ridinium ion>alkyl trimethylammonium ion. For a homologous series of cationic surfactants, the selectivity coefficient increased regularly with increasing alkyl chain length.
  • Masaru Nakahara, Yosuke Yoshimura, Jiro Osugi
    1981 年 54 巻 1 号 p. 99-102
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The volumetric behaviors of cholesteryl oleyl carbonate (COC) and cholesteryl oleate(CO) were investigated around the smectic(Sm)-cholesteric(Ch) and cholesteric-isotropic(I) transitions by using chromatographically purified materials. Both transitions showed marked pretransition phenomena in COC and CO. The transition volumes(ΔV) are; for COC ΔVSm-Ch=0.34 cm3 mol−1 at 22.8 °C and ΔVCh-I=0.66 cm3 mol−1 at 37.5 °C and for CO ΔVSm-Ch=0.88 cm3 mol−1 at 45.4 °C and ΔVCh-I=0.88 cm3 mol−1 at 50.7 °C. The Sm-Ch and Ch-I transitions are first order as predicted by mean-field theories. The pretransition volume around the Ch-I transition can be treated by the Landau-de Gennes theory for the first-order phase transition.
  • Yoshihiro Furukawa, Hideko Kiriyama, Ryuichi Ikeda
    1981 年 54 巻 1 号 p. 103-108
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Molecular motion in solid (CH3NH3)2TeX6 (X=Cl, Br, and I) was studied by measuring the spin-lattice relaxation time, T1, of 1H and 35Cl nuclei in several crystalline phases appearing below room temperature. A deep minimum of the proton T1 was observed in the low-temperature phase of all the compounds, indicating that the methylammonium ion performs a rapid reorientation as a whole about its three-fold axis. The activation energies, Ea, for the motion of cations are determined to be 7.0, 3.7, and 2.7 kJ/mol for X=Cl, Br, and I respectively. In (CH3NH3)2TeI6, which has the lowest Ea value, the relaxation process associated with the tunneling of the cation is apparent at low temperatures. For all the complexes studied, a shallow T1 minimum ascribable to the independent rotation of the CH3 and NH3 groups in the cation was observed on the high-temperature side of each deep T1 minimum. The 35Cl T1 of (CH3NH3)2TeCl6 exhibited a distinct minimum at the lower phase-transition point at 139 K and a discontinuity at the higher one near 230 K. The hindered rotation of the [TeCl6]2− octahedron occurs in the room-temperature phase, with an Ea value of 48 kJ/mol.
  • Kazuo Tajima, Takao Tsutsui
    1981 年 54 巻 1 号 p. 109-113
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The adsorption of N-dodecyl-β-alanine (NDA) was studied at the air–solution interface with the spread film of L-α,β-dimyristoyllecithin (DML) or α,α′-dilaurin (DIL). The adsorbed amounts were measured by radiometry using tritium-labelled NDA, combined with surface pressure measurements. Measurements of IR, DSC, and NMR were made in order to determine the bulk properties of amphoteric moieties in the mixture of DML and NDA. For the mixed monolayer of NDA and DML or DIL, the surface composition vs. area curves were obtained at various surface pressures. The molecular interaction in monolayer was discussed on the basis of the excess free energy of mixing, which was calculated at various surface pressures and compositions. As a result, the mixing of DIL and NDA in monolayer was ideal at surface pressures less than 5 mN m−1, whereas the mixed monolayer of DML and NDA showed a remarkable condensation in surface molecular area. Such a large condensation at low surface pressure was concluded to be due to the formation of ion pairs between the choline and alanine moieties on the water surface, by referring to the findings obtained by studying the lipid properties in the bulk phase. It was also found that the DML–NDA monolayer near close packing exhibited various types of complicated behavior, depending on the surface compositions. The appreciable differences in the nature of the amphoteric moieties in DML and NDA molecules can explain these findings.
  • Takao Tsutsui, Kazuo Tajima
    1981 年 54 巻 1 号 p. 114-117
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The applicability of the Gibbs adsorption isotherm was examined for the adsorption of N-dodecyl-β-alanine (NDA) at the air-solution interface with the spread monolayer of lecithin (DML) or dilaurin (DIL). In order to derive adsorption isotherms, the spread monolayer was treated energetically as a part of the adsorbed monolayer. The isotherms were derived for the following cases: (a) a nonideal mixing of the spread and adsorbed molecules and (b) a nonideal adsorption associated with a conformational change due to the complex formation between monolayer molecules. The isotherm derived for case (a) coincided with the observed isotherm of NDA adsorbed into the DIL monolayer, but deviated from the observed isotherm of NDA adsorbed into the DML monolayer. The DML–NDA isotherm was regarded as to be explained by the isotherm derived for case (b). Further, the applicability of the Pethica’s isotherm to the adsorption of NDA in both systems was examined.
  • Kazunori Yanagi, Yuji Ohashi, Yoshio Sasada, Youkoh Kaizu, Hiroshi Kob ...
    1981 年 54 巻 1 号 p. 118-126
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The crystal structure and absolute configuration of the title compound, (−)589-[Co(bpy)3][Fe(CN)6]·8H2O, has been determined from single-crystal X-ray data. The yellow crystals are triclinic; unit-cell dimensions a=12.174(3), b=16.742(7), c=10.651(3) Å, α=103.25(3), β=104.09(2), γ=94.71(3)°, space group Pl, Z=2. The structure was solved by the heavy-atom method and refined to R=0.076. The (−)589-isomer of [Co(bpy)3]3+ has Δ configuration. The [Co(bpy)3]3+ and [Fe(CN)6]3− ions have an approximate D3 symmetry and nearly the same structure as those in other related complexes. All the N atoms in [Fe(CN)6]3− and the water molecules participate in a three-dimensional hydrogen-bond network.
  • Nobuatsu Watanabe, Kazuo Ueno
    1981 年 54 巻 1 号 p. 127-129
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Properties of fluorine-adsorbed active carbon (FAAC), expected to be a new fluorinating agent, were investigated by means of TG, X-ray diffraction, and ESCA. The fluorine in FAAC was desorbed by heat treatment in a vacuum at temperatures higher than 200 °C. The X-ray diffraction and ESCA measurements suggest that fluorine is inserted between the carbon layer planes of the active carbon, and combines with carbon atoms weakly in comparison with the C–F covalent bond. The reactivity of FAAC against several organic compounds was studied. 1-Butanol, 1-butanethiol, and cyclohexylamine were oxidized. Butyryl chloride was fluorinated to give butyryl fluoride.
  • Mitsuo Abe, Masamichi Tsuji, Masato Kimura
    1981 年 54 巻 1 号 p. 130-134
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The increasing order of ion-exchange selectivity for tervalent metal ions: Al3+<<Ga3+≤Yb3+<Fe3+<La3+<In3+, was established in 1 mol dm−3 nitric acid solution on a crystalline antimonic(V) acid (C-SbA) cation exchanger. Strong correlation was found between the selectivity and the effective ionic radii of these ions. Large separation factors for neighboring ions were obtained, as compared with the commercial ion exchange resin. An effective separation of aluminium(III)-iron(III) ion pairs and a group separation of garium(III) and ytterbium(III) ions from lanthanum(III) ion were performed by using a relatively small C-SbA column (4 cm× 0.4 cm i.d.).
  • Tadao Kanzaki, Jun-ichiro Nakajima, Yutaka Tamaura, Takashi Katsura
    1981 年 54 巻 1 号 p. 135-137
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Zn-bearing spinel ferrites were obtained by air oxidation of the iron(II) hydroxide suspension of the mole fraction Zn(II) to [Zn(II)+Fetotal], rZn, ranging from 0.029 to 0.33 (except for 0.057) at pH 10.0 and 65 °C, but at rzn=0.057 only α-FeOOH was formed. The Zn-bearing spinel ferrite obtained at rZn=0.33 has the normal spinel structure. At pH 8.0, the Zn-bearing spinel ferrite is obtained at rZn=0.057, but the spinel ferrite is slightly oxidized to γ-Fe2O3.
  • Hiroaki Tagawa, Takeo Fujino, Kenju Watanabe, Yumiko Nakagawa, K\={o}j ...
    1981 年 54 巻 1 号 p. 138-142
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The formation and the oxidation-reduction properties of mixed oxides in the Ce–U–O ternary system were examined by means of thermogravimetry and the X-ray diffraction technique. The mixed oxides were prepared by the reactions of CeO2 with U3O8 in air and in hydrogen. The composition of the products heated in air, followed by slow cooling to room temperature, was approximately expressed by this equation: yCeO2+(1–y)UO2.67. By X-ray diffraction, it was shown that the oxides formed at 1100 °C in air were mixtures of Ce0.6U0.4O2.3 and α-U3O8 in the y<0.6 range, while they were in single phases of solid solutions for y≥0.6. When the mixed oxides, MO2+X, where M indicates yCe+(1–y)U, were re-heated in air, weight loss due to oxygen liberation was observed above 500 °C, and it was enhanced with a rise in the temperature. The hydrogen reduction of the oxides proceeded in two steps; the first step was the reduction of MO2+X to MO2 below 600 °C, and the second one was the reduction of MO2 to MO2−X above 600 °C. The composition of the oxides obtained can be given by this equation: yCeO1.81+(1–y)UO2.00. Two separate linear relationships for the lattice parameter of the fluorite-type structure as a function of the cerium content were obtained; one is applicable to the solid solutions with y≤0.6, where the lattice parameter is nearly that of UO2, and the other to the solid solutions with y≥0.4. The latter obeys Vegard’s law between UO2 and CeO2. The oxides with y=0.4–0.6 were in the two-phase region of the solid solutions.
  • Yoshio Shijo, Tokuo Shimizu, Kaoru Sakai
    1981 年 54 巻 1 号 p. 143-145
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The extraction equilibria and the fundamental conditions were studied for extracting the tungsten(VI)–Pyrocatechol Violet complex anion in a form of an ionic associate with tridodecylethylammonium salt in carbon tetrachloride. The ternary complex has an absorption maxima at 575 nm in the organic phase. The optimum pH range for the extraction is 4.8–5.6. The distribution ratio and the molar absorptivity are 3.3×102 and 4.7×104 dm3 mol−1 cm−1 respectively. The composition of the ternary complex is estimated to be WO2(PV)2(R3R′N)2.The extraction constant would be:
    Kex=\frac[WO2(PV)2(R3R′N)2]o[WO2(PV)22−][R3R′N+]2.
    It is given by logKex=13.56. Many foreign cations can be masked with CyDTA.
  • Masao Sekizaki
    1981 年 54 巻 1 号 p. 146-149
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Bis(perchlorato)bis(pyrazine-2,3-dicarboxamide)copper(II) has been prepared, and its crystal and molecular structure has been determined by the X-ray diffraction and the infrared spectroscopic methods. The crystals are triclinic with a space group P\bar1; a=10.959(4), b=6.970(3), c=7.666(3) Å, α=116.63(3), β=78.14(5), and γ=97.27(5)°, and Z=1. The refinement of the crystal structure has been carried out by a block-diagonal least-squares method to give R=0.054 for 1727 non-zero reflections. The complex is centrosymmetric, with the two bidentate ligand molecules chelating to the copper atom in trans positions through the amide oxygen and pyrazine nitrogen atoms to form a square-plane. The two perchlorate ions coordinate weakly to the copper atom through the oxygen atoms from the top and bottom of this plane; thus, an elongated octahedron is formed. The complex molecules are connected to one another by N–O type hydrogen bonds to form a three-dimensional network. The infrared spectrum has been compared with that of the chloride complex. The KBr region clearly show the symmetry depression of the perchlorate ion from Td to C3v on coordination.
  • Yoshiaki Ito, Shinichi Kawaguchi
    1981 年 54 巻 1 号 p. 150-158
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The MnCl(β-dik)2 complexes, where β-dik stands for an anion of acetylacetone, benzoylacetone, and dibenzoylmethane, were confirmed to have the five-coordinate structure in dichloromethane and their adduct formation constants with various donor solvents were measured. Equilibria and kinetics of substitution reactions of MnCl(β-dik)2 with other β-diketones were determined by the spectrophotometric method and the mechanism for these reaction is proposed.
  • Kenji Ishikawa, Gin-ya Adachi, Midori Tanida, Jiro Shiokawa
    1981 年 54 巻 1 号 p. 159-162
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Mixed oxides containing bivalent europium, EuxNbO3−y (0.5<x<1.0), were synthesized by the solid state reaction of Eu2O3, Nb2O5, and Nb powder. The structural change of EuxNbO3−y from a tetragonal to cubic form takes place at x=0.65. The mechanism of oxidation for the bronzes was studied. Each bronze shows different behavior in oxidation, the cubic bronze giving an amorphous phase and the tetragonal bronze complex crystalline products. EuNbO4 was crystallized from both the amorphous and crystalline phases at 950 K and 1070 K, respectively. TG-DTA and magnetic studies indicated that the oxidized phases play an important role in the rate-determining step of oxidation for the bronzes.
  • Yukito Murakami, Yoshihisa Matsuda, Kazunori Sakata, Sunao Yamada, Yas ...
    1981 年 54 巻 1 号 p. 163-169
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Nickel(II), copper(II), and cobalt(III) complexes were prepared with corroles; 2,3,7,8,12,13,17,18-octaethylcorrole (OEC), 2,3,17,18-tetramethyl-7,8,12,13-tetraethylcorrole (MEC), and 8,12-bis[2-(ethoxycarbonyl)ethyl]2,3,7,13,17,18-hexamethylcorrole (PMC). For the coordination with nickel and copper ions, the corroles acted as dianionic ligands to yield electrically neutral complexes. These complexes exhibited metalloporphyrin-like electronic spectra, while they showed spectra which bear a much closer resemblance to those for metalloporphyrins as the anionic complexes were formed upon addition of alkali. The corroles coordinate to tervalent cobalt as trianionic ligands to form neutral complexes, which were reduced to the corresponding cobalt(II) complexes with sodium hydroborate. These reduced species gave a unique set of g-values (g1>>g2>g3) for the complexes of macrocyclic ligands with conjugated double bond system. The plausible coordination geometry as well as the structural properties of the corrole ligands has been discussed.
  • Taira Imamura, Takayuki Numatatsu, Masashi Terui, Masatoshi Fujimoto
    1981 年 54 巻 1 号 p. 170-174
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    New tetraphenylporphyrin complexes, MoO(tpp)X (X=F, Br, BF4, NCO, N3, and NCS), are easily prepared from the complex, MoO(tpp)OC2H5, where TPP denotes meso-tetraphenylporphyrin. The complexes are confirmed to contain a central oxomolybdenum(V) group based on the IR and the ESR measurements. The visible absorption spectra of the complexes in dichloromethane have three main peaks, the Soret band, the α and the β bands. The degree of red shifts of the corresponding absorption maxima is found to increase in the order: X=OC2H5<BF4\simeqF<NCO<N3<NCS<Cl<Br, accompanied with the same order of the change in the ratio εαβ. The correlation is also observed between the red shifts of the absorption peak around 330 nm and those of the Soret band. The complexes, MoO(tpp)X, are classified to d-type hyperporphyrin.
  • Yoshikiyo Kato, Akifumi Yamada, Norimasa Yoshida, Kei Unoura, Nobuyuki ...
    1981 年 54 巻 1 号 p. 175-180
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Window sweep chronopotentiometry, a new galvanostatic method, has been worked out, the electronic circuit of a window sweep chronopotentiograph and digital simulation of the window sweep chronopotentiogram being presented. Analytical application demonstrating the increase in sensitivity of the galvanostatic method for quantitative analysis is presented.
  • Toshihiko Uchiyama, Yoshio Toshiyasu, Yukio Nakamura, Toshio Miwa, Shi ...
    1981 年 54 巻 1 号 p. 181-185
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The reaction of platinum(II) chloride with neat benzonitrile gave bis(benzonitrile)dichloroplatinum(II) as a mixture of cis and trans isomers in variable proportions, depending on the temperature. The geometry of the chromatographically separated isomers was identified on the basis of the dipole-moment and IR data. The 13C NMR spectra in CDCl3 also enabled us to discriminate between isomers in both chemical shift and coupling to the 195Pt of the cyanide carbon, the resonance peak of which was utilized to follow the isomerization. The rate constant (kc) for the cis-to-trans isomerization was found to be (3.8±0.3)×10−6 s−1 in CDCl3 at 25 °C, ten times larger than that [kt=(2.9±0.2)×10−7 s−1] of the reverse reaction. The equilibrium between cis and trans strongly favored trans in CDCl3 at 25 °C, whereas in benzonitrile the cis form was the dominant species at room temperature, while the trans form was dominant at higher temperatures.
  • Takao Komatsu, Matsuo Nonoyama, Junnosuke Fujita
    1981 年 54 巻 1 号 p. 186-189
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Cyclo-palladated (dimethylaminomethyl)ferrocene has been resolved into optically pure enantiomers via the (S)-proline derivatives. The absolute configuration is assumed by comparing the circular dichroism spectrum with that of similarly cyclo-palladated (S)-[1-(dimethylamino)ethyl]ferrocene of the known configuration. Several optically active derivatives of the cyclo-palladated (dimethylaminomethyl)ferrocene have been prepared and characterized.
  • Kazumasa Hata, Myung-Ki Doh, Kazuo Kashiwabara, Junnosuke Fujita
    1981 年 54 巻 1 号 p. 190-195
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Cobalt(III) complexes of new sexidentate ligands,N,N,N′,N′-tetrakis(2-aminoethyl)-1,3-propanediamine (ttn), -1,4-butanediamine (ttmd), and -(R,R)- and -(R,S)-2,4-pentanediamine (tptn) were prepared and resolved except the RR-tptn complex which formed the Δ-isomer stereoselectively. The monocyano complexes of N,N,N′,N′-tetrakis(2-aminoethyl)-1,2-ethanediamine (ten) and ttn, in which the ligands act as a quinquidentate, were also prepared. Absorption and CD spectra of these complexes and the known [Co(ten)]3+ complex were compared with one another. The first d-d absorption bands of the sexidentate complexes, [Co(A)]3+ are shifted to smaller wave numbers in the order, ttn>ten>ttmd for A, but those of [Co(CN)(HA)]3+ are in the reverse order, ten>ttn. The d-d absorption bands of [Co(RS-tptn)]3+ which contains one axial methyl group show the remarkable red shift and the hyperchromic effect as compared with those of [Co(RR-tptn)]3+ with two equatorial methyl groups.
  • Yoko Saito, Toshio Takeuchi, Yutaka Fukuda, Kozo Sone
    1981 年 54 巻 1 号 p. 196-199
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    It was found that the mixed chelates of nickel (II) with the general formula [Ni(diam)(β-dik)2], where diam means an N,N- or N,N′-alkylated ethylenediamine and β-dik a β-diketonate anion, are highly volatile, fusible, and often amazingly soluble in nonpolar solvents like CCl4, benzene, or heptane. Representative data on these properties are presented and their correlations with the structures of the ligands are discussed.
  • Akio Yuchi, Yumi Yagishita, Shinkichi Yamada, Motoharu Tanaka
    1981 年 54 巻 1 号 p. 200-206
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Kinetic and equilibrium studies were made on the esterification of the μ-oxo dimeric vanadium (V) complexes with monoanionic bidentate ligands(HL) such as 8-quinolinol, 5-chloro-8-quinolinol, 5,7-dibromo-8-quinolinol, and 4-isopropyltropolone by butyl alcohols (ROH) in chlorobenzene. The stoichiometry and the rate equation are expressed as follows:
    V2O3L4+2ROH\ ightleftharpoons2VO(OR)L2+H2O:KDE;
    −\fracd[V2O3L4]dt=\frac12×\fracd[VO(OR)L2]dt=(k1+k2[H2O])[V2O3L4][ROH].
    The more basic the bound ligand L, the lower the water-independent rate constant k1 is. For less sterically crowded alcohols, k1 is higher, giving the reactivity order: n->i->s->t-. Water, presumably hydrogen bonded to the terminal oxo group of the complexes, accelerates the esterification(k2 path). The equilibrium constant KDE is linearly correlated with the rate constant k1. The esterification kinetics of the monomeric complex with 2-methyl-8-quinolinol(HL′), which corresponds to the proposed reactive intermediate in the esterification of the μ-oxo dimeric complexes, is also investigated and found the rate equation to be expressed as
    −\fracd[VO(OH)L′2]dt=\fracd[VO(OR)L′2]dt=kM,1[VO(OH)L′2[ROH].
    kM,1 is 5 times higher than the estimated for the corresponding dimeric complex. Large negative values of ΔS1\ eweq and ΔSM,1\ eweq point to an associative nucleophilic attack of alcohol to the vanadium center of both dimeric and monomeric complexes. The difference of the reactivity of complexes and alcohols and the detailed mechanism will be discussed.
  • Setsuko Kudo, Akio Iwase, Nobuyuki Tanaka
    1981 年 54 巻 1 号 p. 207-211
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The d.c. polarographic reduction of Ni(acac)2 and Ni(hfac)2 was studied in detail in dimethyl sulfoxide. Two kinds of tetraalkylammonium perchlorates and sodium perchlorate were used as supporting electrolytes. Ni(acac)2 gave three waves in all the supporting electrolytes, while Ni(hfac)2 gave two waves in the presence of tetraalkylammonium perchlorate. These waves were explained on the basis of the polarographic properties, molecular weights, and conductivities. The electrode reaction mechanism of Ni(acac)2 can be expressed by:
    (Remark: Graphics omitted.)
    where the second wave includes a kinetic current. The first wave of Ni(hfac)2 is due to the reduction of Ni(hfac)+ and Ni(hfac)2 themselves; the second wave corresponds to that of free hexafluoroacetylacetonate.
  • Shuichi Tono-oka, Yasuhiko Sasahara, Akio Sasaki, Haruhisa Shirahama, ...
    1981 年 54 巻 1 号 p. 212-216
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Two β-NAD-analogs were prepared utilizing a base-exchange reaction catalyzed by pig-brain NADase. These analogs were proved to contain a methyl 1,4-dihydro-4-iminonicotinate and a 1,4-dihydro-4-iminonicotinamide moiety. By successive hydrolytic degradations of these analogs, 1,4-dihydro-4-iminopyridine β-ribosides with 3-carboxyl and 3-carbamoyl groups were prepared in good yields. The former compound was identical with clitidine, a toxic pyridine nucleoside recently isolated from a toadstool. The present synthesis confirmed the 1,4-dihydro-4-imino β-riboside structure of clitidine. Preliminary biological tests showed that the 3-carbamoyl compound was more toxic than clitidine, suggesting that the amide derivative of clitidine is an essential toxic substance in the toadstool.
  • Tomio Shimizu, Yoshiyuki Hayashi, Kazunari Yamada, Toshiyuki Nishio, K ...
    1981 年 54 巻 1 号 p. 217-222
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The reaction of 2H-1-benzopyran with several 1,3-dipoles gives cycloadducts in good yields. The orientation of the cycloaddition is qualitatively interpreted in terms of FMO theory. These heteropolycyclic compounds were also obtained from hydrazones of 3-aroyl-2H-1-benzopyrans, prepared from 3-cyano-2H-1-benzopyran.
  • Akira Tai, Kazuhisa Ito, Tadao Harada
    1981 年 54 巻 1 号 p. 223-227
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The hydrogenation of acetylacetone (I) over asymmetrically modified Raney nickel (MRNi) proceeded, step by step, as follows: acetylacetone (I)\oversetStep 1→ 4-hydroxy-2-pentanone (II) \oversetStep 2→ 2,4-pentanediol (III). It was demonstrated that the optical yield of Step 1 and the diastereomer excess of Step 2 are governed by the ratio of the stereo-differentiating reaction site to the non-stereo-differentiating reaction site on the catalyst. The stereochemistry of each step was also discussed based on the mode of the intermolecular hydrogen bondings between the substrate and tartaric acid adsorbed on the catalyst. RNi modified with a mixture of tartaric acid and NaBr (TA–NaBr–MRNi) gave the best result with respect to both Step 1 and Step 2.
  • Nobuo Ikuta, Joichi Koga, Nobuhiko Kuroki
    1981 年 54 巻 1 号 p. 228-233
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The proton equilibria of an optical probe, the 5-dimethylamino-1-naphthalenesulfonyl group, conjugated to bovine serum albumin with various molar ratios to the protein in an acidic solution, were investigated by means of the change in the fluorescence intensity as well as that in the absorbance. Below the molar ratio of 1.7 the apparent pK values for the dimethylamino moiety of the optical probe decreased remarkably with a decrease in the pH of the solution, accompanying conformational changes of the protein caused by the proton binding to the protein. For molar ratios of more than 2.0, the alternation of the higher structure of the protein induced by the conjugation of the probe was detected by ORD measurements, while the pK values of those conjugated probes were lowered at pH’s higher than 3.0. For comparison, the probe conjugated with glycine as its free state gave the pK value of 3.99 in an aqueous solution. The shifts of the apparent pK values of the conjugated probe in the protonated protein compared with those for the free probe were, particularly, too large to arise from the Debye-Hückel electrostatic shielding effect. These results are, therefore, interpreted in terms of a change in the shortrange interaction in the neighboring residues surrounding the probe.
  • Yasushi Yokoyama, Yoshihiko Moriyama, Takahiko Tsuyuki, Takeyoshi Taka ...
    1981 年 54 巻 1 号 p. 234-239
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Backbone rearrangements of 3α,4α- and 3β,4βepoxy-D:A-friedo-18β,19αH-lupanes catalyzed by boron trifluoride etherate gave 18β,19αH-lup-12-en-3-ols, lup-18-en-3-ols, and lup-19-en-3-ols, besides known D:B-friedo-18β,19αH-lup-5-en-3-ols and -5(10)-en-3-ols. D:B-Friedo-18β,19αH-lup-l(10)-en-3α-ol and 3β,10β-epoxy-D:B-friedo-18β,19αH-lupane were also obtained from α- and β-epoxides, respectively. Solvent effects on these reactions were examined.
  • Toshikazu Ibata, Kimiko Jitsuhiro, Yoshie Tsubokura
    1981 年 54 巻 1 号 p. 240-244
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    1,3-Dipolar cycloadducts were obtained in the reactions of 1-methoxy-2-benzopyrylium-4-olate (3a) with ethylenic dipolarophiles, such as dimethyl fumarate, dimethyl maleate, maleic anhydride, trans-1,2-dibenzoylethylene, N-substituted maleimides, and acenaphthylene. The configuration of the adducts was determined on the basis of the NMR coupling pattern of the methine protons of the adducts in connection with a deuterium experiment. The previously reported structure of the adduct of 3a with dimethyl fumarate was corrected according to the experimental results obtained using 3-deuterated 3a. The stereospecificity of the cycloaddition was confirmed in the reactions of dimethyl fumarate, dimethyl maleate, and trans-1,2-dibenzoylethylene; this stereospecificity was explained by the concerted (π2S+π4S) mechanism. The exo/endo ratios of the adducts of N-substituted maleimides may be explained by the combination of the steric repulsion and π-π interaction of the phenyl ring of 3 and the substituent on the N-atom of maleimides. The cycloadditions of 1-methoxy-3-methyl-2-benzopyrylium-4-olate with N-substituted maleimides were also explained in a similar manner.
  • Kazuhisa Murata, Akio Matsuda
    1981 年 54 巻 1 号 p. 245-248
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    Polar ether solutions prepared in situ from Co2(CO)8 and 1,2-bis(diphenylphosphino)ethane (diphos) are active catalysts for the hydroformylation of propene with CO and H2O. Under the hydroformylation conditions employed, butyl (C4) or isobutyl alcohols, butyric (C4) acids, and dipropyl ketones were found to be formed as by-products. A pronounced formation of C4 alcohols was observed as the reaction temperature was increased; in fact, the catalyst solutions described above actively reduce butyraldehyde to butyl alcohol. The effects of the CO pressure and of the propene concentration on the formation of C4 aldehydes are also examined. It turns out that the water molecule as well as Co2(CO)8 and diphos are essential for the formation of catalytic intermediates, which are themselves responsible for the hydroformylation activity.
  • Kazuhisa Murata, Akio Matsuda
    1981 年 54 巻 1 号 p. 249-252
    発行日: 1981年
    公開日: 2006/06/02
    ジャーナル フリー
    The hydrocarbonylation of propene with CO and H2O to give dipropyl ketones occurs predominantly over forming C4-aldehydes; the catalyst solutions employed are prepared in situ from Co2(CO)8, various phosphines as ligands, and H2O, a high molar ratio of propene to Co2(CO)8 of 300/2 being required. Of the several phosphorus ligands examined, 1,2-bis(diphenylphosphino) ethane (diphos) and bis(diphenylphosphino) acetylene are relatively effective for the formation of the ketones (abbreviated as [ketones]). The effects of the reaction variables (CO pressure, temperature, and H2O concentration) on [ketones] are also examined using the Co2(CO)8–diphos system; [ketones] increases with the initial increase in CO pressure, but reaches a maximum at ca. 100 kg/ cm2 and decreases thereafter. Pronounced decreases of [ketones] are observed when pyridine as well as hydrogen is added to the catalyst solutions.
feedback
Top