Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
49 巻 , 1 号
選択された号の論文の82件中1~50を表示しています
  • Hiroyasu Sato, Shin-ichi Arase
    1976 年 49 巻 1 号 p. 1-7
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Infrared study was made on aniline adsorbed on aluminum chloride, bromide and iodide. Aniline-d0 (C6H5NH2), aniline-N,N-d2, aniline-d5 (C6D5NH2) and aniline-d7 were used. Aniline-d0–gallium chloride system was studied for comparison. Only the bands associated with amino group showed large frequency shifts on complex formation. The structures of adsorbed molecules were discussed in terms of the frequency shift of bands, especially of those assigned to C–N stretching and ND2 bending modes. The interaction of adsorbed aniline with aluminum chloride is rather weak and predominantly ionic. A strong chemisorption with the formation of an essentially covalent N···Al bond can be deduced for aniline adsorbed on aluminum bromide, iodide and gallium chloride. Such an ionic adsorption on aluminum chloride can be understood by considering the ionic structure of solid aluminum chloride. Some of the observed bands for aniline-d5 are (cm−1); 3424, 3350, 3312 (NH str.), 1620 (NH2 bend.) and 1300 (CN str.).
  • Tadashi Watanabe, Akira Fujishima, Osamu Tatsuoki, Ken-ichi Honda
    1976 年 49 巻 1 号 p. 8-11
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    For an interpretation of the pH-dependence of the sensitized photocurrent at semiconductor electrodes, measurements have been carried out on n-type TiO2 and CdS single crystal electrodes. As sensitizing dyes, rhodamine B and 3,3′-diethylthiacarbocyanine iodide which remain stable in a sufficiently wide pH range were used. It has been found that the logarithm of the sensitized photocurrent at TiO2 electrode depends linearly on the pH of the electrolyte solution, whereas the sensitized photocurrent shows practically no pH-dependence at CdS electrode. These observations have been accounted for on the basis of the different pH-dependence of flatband potentials of these semiconductor electrodes.
  • Keizi Hashimoto, Shozi Watanabe, Kimio Tarama
    1976 年 49 巻 1 号 p. 12-15
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    In order to determine the active center of ethylene polymerization over MoO3–Al2O3, the g-tensor and the amount of molybdenum(V) in each chemical state were determined by means of ESR measurement. The anisotropy of the g-tensor revealed the strength of the crystal field in the state; the decreasing order of the strengths was as follows: state(S)>state(M)>state(W)>MoO3–SiO2\fallingdotseqfree MoO3. In the state(S) molybdenum oxide is insoluble in aq.10M–NH3, in the state(M) it is soluble in aq. NH3 but insoluble in water, and in the state(W) it is soluble in water. The amount of molybdenum(V) in the state(W) was studied in connection with the activity, because only the state(W) was suitable for polymerization. The behavior of the activity was in fair agreement with that of the molybdenum(V) content in the state(W) and this content depedned on the amount of supported MoO3 and on the extent of reduction. The amount of molybdenum(V) in the state(W) corresponded to the amount of chemisorbed hydrogen, which was a polymerization initiator. The chemisorption of oxygen on the catalyst caused a complete disappearance of both the activity and the molybdenum(V) content in the state(W). Therefore, it was concluded that the active center of the polymerization was molybdenum(V) in the state(W).
  • Yoshitsugu Oono
    1976 年 49 巻 1 号 p. 16-19
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    A simple method for the estimation of thermal expansivity of the molecular liquid is proposed. Thermal expansivity a can be calculated by
    α=T−1φ(y)⁄yφ′(y),
    where φ(y)=ph⁄ρkT,y=πρa3⁄6,ph is the pressure of a hard sphere fluid, a the effective hard core diameter of the molecule, ρ the number density, and k, T have their usual meanings. For the molecular liquids consisting of compact molecules, the equation gives a fairly accurate estimation of α, which is practically applicable to the estimation of the density of the liquids at 1 atm at desired temperature.
  • Kohichi Yamamoto, Shigeo Hayano
    1976 年 49 巻 1 号 p. 20-25
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The specific adsorption of bromide ions on a mercury electrode from lithium bromide solutions of dimethyl sulfoxide (DMSO) has been studied through the measurement of the differential capacity and the interfacial tension. The capacity data showed the evidence that anions are more weakly, but cations are more strongly, solvated by DMSO molecules than by H2O. The amounts of specifically adsorbed bromide ions are greater than those values in water at the same electrode charge. The specific adsorption of cations (Li+) was not found in this study. The inner layer capacity due to the amounts of specific adsorbed anions was calculated, and the ratio of the distances from the metal to the inner Helmholtz plane and to the outer Helmholtz plane were deduced. These values are comparable to those for LiCl in DMSO, but are greater than for water.
  • Katsuyuki Aoyagi
    1976 年 49 巻 1 号 p. 26-28
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The rf electric field in circular concave electrodes for longitudinal ion cyclotron resonance is investigated. The potential equation of this rf electric field is theoretically derived from Laplace’s equation. The equation of the motion of an ion which moves under the simultaneous application of the magnetic field and this rf electric field was solved. The solution of this equation is used to obtain the instantaneous and total power absorptions of the ion from the rf electric field. The power absorption expression is used to derive the line-shape expresssions of the longitudinal ion cyclotron resonance.
  • Keiichi Sera, Keigo Suehiro, Michiro Hayashi, Hiromu Murata
    1976 年 49 巻 1 号 p. 29-33
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The infrared spectra of chloro(chloromethyl)methylsilanes ClCH2SiCl3−n(CH3)n (n=0–2) in the liquid and crystalline states and a part of the Raman spectra in the liquid state have been measured. It has become apparent that, for ClCH2SiCl2CH3 and ClCH2SiCl(CH3)2, two rotational isomers coexist in the liquid state, while only one isomer persists in the crystalline state. The fundamental vibrations for these molecules have been assigned, and the normal vibrations have been calculated on the basis of a modified Urey-Bradley force field. The solvent effects and the calculation of the normal vibrations have indicated that the gauche form for ClCH2SiCl2CH3 and the trans form for ClCH2SiCl(CH3)2 persist in the crystalline state. For ClCH2SiCl3, the barrier height, V3(SiCl3), has been estimated to be 4.6 kcal/mol from the torsional force constant.
  • Shigeyoshi Miyagishi
    1976 年 49 巻 1 号 p. 34-37
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The CMC values of dodecylammonium chloride and iodide and of hexadecylammonium chloride were measured in water upon the addition of acetone, 1-propanol, and urea at several temperatures. The effects of the additives were most remarkable on the CMC of hexadecylammonium chloride at 45.0 °C. Urea was less effective on the disruption of micelles than acetone, while the addition of 1-propanol was most effective. The enthalpy of micellization became more negative, while the entropy of micellization became less positive, as the additive concentration increased. We divided the standard free energy of micellization into the hydrophobic term, ΔG°n, and the hydrophilic term, ΔG°p. The value of ΔG°p became more negative with the additive concentration and contributed to the stabilization of the micelle, while ΔG°n became less negative. Therefore, it was concluded that the disruption of the micelle in the presence of these organic additives results from an increase in the free energy in the hydrophobic group of the surfactant molecule.
  • Ryoka Matsushima, Kenichi Mori, Morio Suzuki
    1976 年 49 巻 1 号 p. 38-41
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Irradiation of benzaldehyde in a deoxygenated aqueous acetone solution in the presence of the uranyl ion with light of λ≥365 nm gives the U(IV) species and benzil (1) as the main photoredox products, and small amounts of 4-hydroxy-4-phenylbutan-2-one (2), trans-4-phenyl-3-buten-2-one (3), and an unidentified product (4). None of them are formed in the absence of the uranyl ion. The products 2 and 3 are assumed to be formed by the uranyl ion-photocatalyzed condensation of benzaldehyde with acetone. Irradiation of acetophenone in the presence of the uranyl ion gives no photoproducts, though the uranyl emission is effectively quenched. p-Methoxybenzaldehyde and p-chlorobenzaldehyde give the corresponding 4,4′-disubstituted benzils respectively by irradiation under similar conditions. The quantum yield for the formation of the U(IV) species decreases whereas the quenching constant increases with the increase in the electron donating power of the substituent. The physical quenching process appears to compete significantly with the chemical (redox) process. The relative importance of the physical quenching to the chemical quenching process has been estimated. As to the photocatalyzed aldol condensation, the excess vibrational energy, which the quencher and/or the quenchee would possess during or immediately after the quenching interactions, may possibly be converted into the energy of the chemical reaction.
  • Michiya Itoh, Yoshiro Kumano, Toshihiko Okamoto
    1976 年 49 巻 1 号 p. 42-45
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The exciplex (above ∼150 K) and EDA complex (below ∼120 K) fluorescence were observed in the 9,10-dicyanoanthracene and several alkylbenzene systems and also in the intramolecular system of (9,10-dicyanoanthracene)-(CH2)3-(pentamethylbenzene) in the nonpolar solvents. The exciplex fluorescence lifetimes and maxima both in the inter- and intramolecular systems exhibit the continuous change to those of the corresponding EDA complex, which implies the identical fluorescent state of the exciplex and EDA complex. The fluorescence lifetimes and the fluorescence polarization suggest that the fluorescent state of both exciplex and EDA complex may be mostly locally excited state of electron acceptor.
  • Masaaki Sakakibara, Fuyuhiko Inagaki, Issei Harada, Takehiko Shimanouc ...
    1976 年 49 巻 1 号 p. 46-52
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The rotational isomerism of methyl vinyl ether, ethyl vinyl ether, and n-butyl vinyl ether has been studied by means of the vibrational spectra and normal frequency calculations. The enthalpy difference between the skew and cis isomers in the liquid state of methyl vinyl ether has been determined to be 1440±160 cal/mol. Series of C–O torsional transitions in the cis well have been observed for methyl vinyl ether and methy-d3 vinyl ether in the region near 230 cm−1 and analyzed. It has been concluded for ethyl vinyl ether that the cis-trans form (CT) is stable in the solid state and that three forms, CT, SG′, and ST, coexist in the liquid and gaseous states. The spectra in the solid state of n-butyl vinyl ether are consistent with the calculated frequencies of the CTTT form.
  • Masaharu Tsuji, Teiichiro Ogawa, Totaro Imasaka, Yukio Nishimura, Nobu ...
    1976 年 49 巻 1 号 p. 53-57
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    By the impact of an electron beam (100–450 eV) on aliphatic hydrocarbons (C2H2, C2H4, C4H6), cyclo-octadienes, and aromatic molecules (C6H6, C10H8, C12H10, etc.) at about 10−3Torr, the Schüler’s T spectrum of diacetylene ion (A2Πu–X2Πg) was observed in the 505–570 nm region, in addition to the well-known systems of H(Balmer), CH(A–X), and C2(Swan). Three different kinds of mechanisms for the formation of C4H2+ (A) were derived from the dependence of the emission intensity on the electron-beam current and the gas pressure: (a) the primary excitation process (C4H6), (b) the secondary excitation process (aromatic molecules, cyclooctadienes), and (c) the dimerization excitation process (C2H2, C2H4). The intensity ratio (C4D2+/C4H2+) of the T spectrum from C6H6 and C6D6 was 0.83±0.04 for the (0,0) sequence at 300 eV excitation.
  • Yoshifumi Nakacho, Takeshi Misawa, Takaji Fujiwara, Akio Wakahara, Ken ...
    1976 年 49 巻 1 号 p. 58-61
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The crystal of bis(2-chlorobenzoato)zinc(II) is monoclinic, space group P21/c, a=7.284, b=10.480, c=19.091 Å, β=95.59°, and Z=4. The structure was solved by usual heavy atom method and refined to the final R-value of 0.052. In the crystalline state, the complex forms a chain. Each zinc atom is bonded to four oxygen atoms from four different ligands.
  • Kuniaki Matsui, Keiichi Fukuyama, Kumiko Tsukihara, Tomitake Tsukihara ...
    1976 年 49 巻 1 号 p. 62-65
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The structure of a bromoacetate of hydroxypiperenone, C24H31O7Br, has been determined by the X-ray diffraction method. The compound crystallized in the space group P21 with a=8.296, b=13.247, c=11.400 Å, and β=102.8°. The structure was solved by the heavy-atom method and refined to R=0.075 for 1614 reflections. The present analysis has established that the five- and six-membered rings are fused in the cis fashion. The absolute configuration of the molecule has been determined by using the anomalous dispersion effect of the bromine atom for Cu Kα radiation.
  • Shigeru Ikuta, Kenji Yoshihara, Takanobu Shiokawa
    1976 年 49 巻 1 号 p. 66-69
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The breakdown curves for C2H5X, n-C3H7X, and n-C4H9X (X=Cl, Br, and I) were obtained by the use of a double mass spectrometer of the perpendicular type. The charge exchange mass spectra for alkyl bromide and alkyl iodide are found to be similar, although those for alkyl chloride are somewhat different from these for bromide and iodide. According to the molecular orbital calculation, the difference of the electronic configuration between chloride and bromide or iodide is found to correspond to the difference of the breakdown curves. The results obtained in this study using larger molecules support our previous analysis on the breakdown processes in smaller molecules: (1) direct scission of the bond which has lost one electron by the charge exchange reaction, (2) electron redistribution, and (3) secondary decomposition (and those of higher order) from the primary fragments. In the case of alkyl chloride, formation of the ion CnH2n+ is ascribed to the elimination of HX from the molecular ion in its electronically ground but vibrationally excited state.
  • Tadaaki Mizoguchi, Yoshiaki Takei, Taijiro Okabe
    1976 年 49 巻 1 号 p. 70-75
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The disproportionation of thiosulfate, trithionate, tetrathionate and sulfite in acidic solutions has been studied at relatively high temperatures. Thiosulfate hardly decomposes in the absence of sulfuric acid, even at 150 °C, but decomposes very easily in the presence of sulfuric acid at 70 °C, forming elemental sulfur, tetrathionate and sulfite. Trithionate decomposes to thiosulfate and sulfate at 70 °C, while tetrathionate decomposes only at temperatures above 130 °C after an induction period forming thiosulfate as an intermediate. Sulfite undergoes disproportionation, giving thiosulfate and sulfate at 150 °C, and then elemental sulfur and sulfate accompanied by intermediate formation of tetrathionate. A disproportionation pathway of low valence sulfur oxyacids including thiosulfate, trithionate, tetrathionate and sulfite has been proposed.
  • Shigeyoshi Sakaki, Hisamichi Kikkawa, Hiroshi Kato, Satohiro Yoshida
    1976 年 49 巻 1 号 p. 76-81
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    CNDO- and INDO-type UHF-MO calculations are carried out on MF6n (M=V(II), Cr(III), Mn(II), Fe(III), Ni(II)), NiCl64−, MnCl64−, MnCl42−, MnBr64−, and CuCl42−. The calculated spin fractions on the ligand orbitals agree well with the experimental values, with a few exceptions. Spin transfers to ligands are mainly attributed to the spin delocalization (SD) mechanism, except those to the 2s and 2pσ, orbitals of the F ligand in CrF63− and VF64−, in which spin transfer to those orbitals results from the spin polarization (SP) mechanism. Unpaired electrons are also transferred into the 4s and 4p orbitals of the central metal ion by the SP mechanism. The spin transfers to the ligand due to both the SD and SP mechanisms increase in the order of F<Cl<Br in MnX64− and NiX64−. The following characterisities of metal-halogen bonds are established; (1) the covalent interaction between the metal d-orbital and the fluorine atom increases in the order Ni(II)<Mn(II)∼ Fe(III)<Cr(III)∼V(II) in MF6n, and (2) in metal-halogen covalent interactions, the s-character of halogen decreases in the order F>Cl>Br, while the p-character increases in the same order.
  • Kazuhiko Sugasaka, Ayako Fujii
    1976 年 49 巻 1 号 p. 82-86
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The complex formation of copper(I) ions in aqueous 5 M Na(Cl, ClO4) solutions was studied by spectrophotometry covering a pH range from acidic to alkaline. Over the range of the chloride concentration of 0.05–5 M in acidic solutions, the complexes CuCl2 and CuCl32− were found. The molar extinction coefficients of the complexes were determined at various wavelengths from 220 to 320 nm. The equilibrium constant for the reaction CuCl2+Cl=CuCl32− was determined to be 1.95. Chloro-hydroxo mixed complexes of copper(I), such as CuClOH, CuCl2OH2−, and CuCl(OH)22− were formed in alkaline solutions and the molar extinction coefficients of these species were estimated. The formation constants βpq=[CuCl2+p(OH)q]/[CuCl2][Cl]p[OH]q of the complexes were evaluated to be as follows: β−11=(1.1±0.1)×10401=(4.1±0.3)×103, and β−12=(3.8±0.7)×106. No polynuclear complex was formed in the solutions.
  • Akitoshi Komura, Mutsuo Hayashi, Hiroto Imanaga
    1976 年 49 巻 1 号 p. 87-91
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The reactions of tungstophosphate with cobalt ion and the properties of heteropolytungstates containing cobalt have been investigated. Unsaturated heteropolyanion PW11O397− produced by the partial degradation of the parent 12-tungstophosphoric acid reacts with cobalt ion to give 11-tungstocobaltophosphate PCoW11O40H25−. Discussion is given on the presence of cobalt in the heteropolyanion and on the above reaction. Both 12-tungstocobaltate-(II) and -(III) are very resistant to acid, but 11-tungstocobaltophosphates lose cobalt ion in strongly acidic solutions to give the parent 12-acid. Some aspects of the spectra of the heteropolytungstates, in which cobalt(II) and cobalt(III), respectively, are present in the specific site, are discussed.
  • Tetsuya Kameyama, Shigeharu Naka
    1976 年 49 巻 1 号 p. 92-96
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The effect of water on crystallization process of coesite was studied at 450 to 700 °C under 30 kbars by using different starting materials. The presence of water under compression and heating was found to have remarkable effects not only on the kinetics of crystallization of coesite also on the morphology of metastable quartz, consequently of coesite crystals. Under anhydrous condition, from amorphous silica and silica glass, the spherulitic aggregates of metastable quartz appeared. The coesite crystals were developed in the spherulites of quartz as elongated crystals with different sizes and appeared to be defective. When synthetic quartz was used as a starting material, however, no formation of spherulitic aggregates of quartz was observed and granular coesite crystals were obtained. Under hydrous condition, granular coesite crystals with homogeneous size were developed rapidly at 450 °C from both amorphous silica and silica glass through the discrete particles of metastable quartz.
  • Mitsutaka Kitamura, Kazuo Yamashita, Hideo Imai
    1976 年 49 巻 1 号 p. 97-100
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The electrolytic reduction of vanadyl acetylacetonate in acetonitrile solution was investigated by means of conventional and AC polarography, cyclic voltammetry and controlled-potential electrolysis. A well-defined polarographic cathodic wave was obtained in a solution containing excess acetylacetone. The wave-form was outwardly a single step with two-electron transfer. However, logarithmic analysis revealed that it consists of two steps. The first step is slightly irreversible, being accompanied by V–O bond breaking, and the second one is controlled by the rate of coupled chemical reactions. The reaction mechanism is discussed in detail. The reversible half-wave potentials of the species [VO(acac)2] and [V(acac)3] were determined to be −1.93 and −1.78 V vs. Ag/0.1 M AgClO4, respectively, from the logarithmic analysis.
  • Shigenobu Yano, Masahiko Saburi, Sadao Yoshikawa, Junnosuke Fujita
    1976 年 49 巻 1 号 p. 101-105
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The circular dichroism (CD) spectra of trans-dichlorobis(diamine)cobalt(III) complexes were measured in methanol solution in the 700–200 nm region, where the diamines have the general formula of NH2CH(R)CH2NH2(R=isopropyl, isobutyl, sec-butyl, benzyl and phenyl) and belong to the S configuration except the phenyl-substituted one. The spectra are essentially the same as thq spectrum of the (S)-propylenediamine ((S)-pn; R= methyl) complex, except for the (R)-C-phenylethylenediamine ((R)-phenen) complex. The variation of the C-substituted alkyl groups has hardly any influence on the CD of the trans-[CoCl2(diamine)2]+ type complexes, demonstrating that the vicinal contribution from the C-substituents can be disregarded in these compounds. The trans-[CoCl2((R)-phenen)2]+ ion shows a CD pattern differing significantly from that of the trans-[CoCl2((R)-pn)2]+ ion in the first absorption band region, suggesting the significance of the vicinal effect due to the C-substituted phenyl group. The CD curve of trans-[CoCl2((−)D-stien)2]+ ion (stien=stilbenediamine) was found to be antimeric to that of the (R)-phenen complex. Taking into account the anomalous vicinal effect of the phenyl groups, the absolute configuration of the (−)D-stien was assigned to the (S,S) configuration.
  • Kazuko Y. Matsumoto, Masao Kato, Yukiyoshi Sasaki
    1976 年 49 巻 1 号 p. 106-110
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The crystal of (NH4)4S2Mo5O21·3H2O contains a discrete polyanion, S2Mo5O214−, formed by reactions in an aqueous solution:
    5Mo7O246−+14SO2+2H+\ ightleftarrows7S2Mo5O214−+H2O
    or 5MoO42−+2SO2+6H+\ ightleftarrowsS2Mo5O214−+3H2O
    It is orthorhombic, with the space group Pbcn and with a=15.096(9), b=13.375(8), c=23.734(7) Å, Dm=2.79, and Dx=2.79g cm−3 for Z=8. The crystal consists of S2Mo5O214− anions connected with each other by hydrogen bonds, with intervening water molecules and ammonium cations. In the polyanion, five MoO6 octahedra are connected by edge sharing, and the two octahedra at the two ends are connected by corner sharing to complete the Mo5O21 ring; the two SO3 trigonal pyramids are attached to the ring from above and below the ring.
  • Yasushi Inoue, Masamichi Tsuji
    1976 年 49 巻 1 号 p. 111-116
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    In order to elucidate the fundamental properties of hydrous titanium oxide as a cation exchanger, the authors examined the stoichiometry of cation exchange and the acid-base property of the exchanger by means of titration curves. The results may be summarized as follows: 1. The equivalent exchange between the hydrogen ion and either the sodium or strontium ion holds over a wide range of conditions, such as the pH, the ionic strength, and the particle size of the exchanger. 2. The method of conditioning for obtaining the exchanger in the pure hydrogen form has been established. 3. The water content in the exchanger depends on the ionic composition. 4. This hydrous titanium oxide is a four-functional, weakly acidic cation exchanger and has the following apparent pK values: pK1 6.7±0.1, pK2 10.3±0.2, pK3 12.3±0.2, and pK4 13.2±0.2. The corresponding apparent ion exchange capacities are 2.2±0.1, 1.2±0.2, 0.7±0.3, and 0.2±0.3 meq. Na+/g respectively.
  • Naohide Matsumoto, Yuzo Nishida, Sigeo Kida, Ikuhiko Ueda
    1976 年 49 巻 1 号 p. 117-121
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The structure of the trinuclear complex, formed from N,N-diethyl-N′-(3-hydroxypropyl)ethylenediamine and copper(II) perchlorate, has been determined from three dimensional X-ray diffraction data. The crystals are monoclinic with the space group P21/c. The cell dimensions are a=7.759(6), b=13.21(1), c=15.00(1) Å and β=103.95(6)°. The unit cell contains two molecules and the molecule has a centre of symmetry. The structure has been determined by the heavy atom method and refined by the block diagonal least squares method to give R=6.83% for 1368 observed reflections. Three copper atoms are arrayed on a straight line, the separations being 2.902 Å. The geometry around the two end copper atoms is best described as a slightly distorted tetragonal pyramid. The central copper atom has a square planar environment.
  • Eiki Itabashi, Ikuko Yusa
    1976 年 49 巻 1 号 p. 122-126
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Simple and sensitive methods have been developed for the determination of nickel(II), based on the catalytic polarographic current in acidic thiocyanate solution in the presence and absence of cobalt(II). The basis of the methods and the effect of variables have been investigated and elucidated. In the absence of cobalt(II), thiocyanate solution containing large amounts of hydrogen ions serves a supporting electrolyte, while an acidic thiocyanate solution containing tetra-n-butylammonium salts is suitable for the determination of nickel(II) in the presence of cobalt(II). These methods are applicable to the determination 2×10−6 M nickel(II) in the presence and absence of 1×103 M cobalt(II).
  • Masayasu Kurahashi, Akira Kawase
    1976 年 49 巻 1 号 p. 127-130
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The crystal structure of 1-(2-thiazolylazo)-2-naphtholatodiaquacopper(II) perchlorate, [CuII(TAN)(H2O)2]-ClO4, has been determined from three-dimensional X-ray data collected by counter methods. The crystals are monoclinic, with the space group P21/c; a=13.481(4), b=8.060(4), c=15.307(7) Å, β=95.58(4)°, and Z=4. The structure was refined to an R value of 0.086 for 952 non-zero reflections. The copper atom is five-coordinated and has a distorted square-pyramidal environment. The 1-(2-thiazolylazo)-2-naphtholato group (TAN) acts as a terdentate ligand, the phenolic oxygen, the azo nitrogen and the thiazole nitrogen atoms being coordinated to the copper atom to give two five-membered chelate rings. The remaining two positions are occupied by water molecules.
  • Akitoshi Komura, Yasuzi Ikeda, Hiroto Imanaga
    1976 年 49 巻 1 号 p. 131-137
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Reactions of the complex ion [Mo2O4(C2O4)2(H2O)2]2− (I) have been investigated. On acidification with perchloric acid and hydrochloric acid, complex (I) gave molybdenum(V) aqua-dimer ion [Mo2O4(H2O)6]2+, which was converted into the monomeric species [MoOCl5]2− in concentrated hydrochloric acid. The initial reaction of complex (I) with mercaptoacetic acid, giving a complex of stoichiometry 1 ligand: 1 Mo, was followed by a slower reaction which probably gave higher complexes. In the reactions with o-aminophenol and 2,2′-bipyridyl, complexes of stoichiometry 1 ligand: 1 Mo and 1 ligand: 2 Mo, respectively, were formed in solutions. The following complexes have been isolated: Mo2O4(dtc)2, Mo2O3(dtc)4 (dtc=diethyldithiocarbamate), MoOCl3. phen (phen=1,10-phenanthroline), and Mo2O3Cl4(bpy)2 (bpy=2,2′-bipyridyl). The infrared and electronic spectra of the complexes and their probable structures are given. The relative ease of replacement of ligands from complex (I) has been discussed.
  • Takeshi Miyamoto, Kazuo Fukushima, Taro Saito, Yukiyoshi Sasaki
    1976 年 49 巻 1 号 p. 138-142
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    New complexes of N-allylpyrazole(L) with Pd(II) and Pt(II) have been prepared and characterized; they have the general formulae of MX2L2 and MX2L (X=Cl or Br). IR and 1H NMR studies indicate that the latter complexes are cis-planar-chelate and involve both the pyrazolyl nitrogen and the olefinic group in bonding to the metal, while the former are syn- and anti-trans-planar and contain only uni-dentate pyrazole donor ligands. The treatment of the chelate complex PtCl2L(L=1-(2-methylallyl)-3,4,5-trimethylpyrazole) with donor ligands (L′) such as phosphines, AsPh3, and py displaces the coordinated olefin,forming cis-PtCl2LL′ with a retention of the cis-configuration.
  • Kazuo Fukushima, Akiko Kobayashi, Takeshi Miyamoto, Yukiyoshi Sasaki
    1976 年 49 巻 1 号 p. 143-146
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The crystal structure of (1-allyl-3,5-dimethylpyrazole) copper (I) chloride, CuCl(C8H12N2), has been determined by the three-dimensional X-ray analysis. The crystal is triclinic, space group P\bar1; a=8.442(4), b=8.873(6), c=8.112(3) Å, α=103.44(3), β=116.42(3), γ=63.37(3)° and Z=2. The structure was refined to an R value of 0.056 for 1196 collected reflections. The complex has a dimeric structure in which the copper(I) ion is surrounded quasi-tetrahedrally by two bridging chlorines, a pyrazole-nitrogen and the olefinic part of the allyl group. The C=C bond distance (1.34 Å) scarcely shows any increase upon coordination to the metal. The olefin plane is almost perpendicular to the Cu-olefin bond axis and shows no significant bendings of the olefinic atoms out of the plane.
  • Ichiro Hirako, Tasuku Murakami, Masahiro Hatano
    1976 年 49 巻 1 号 p. 147-150
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Some nickel(II) complexes with optically active ethylenediamine-N,N′-diacetic acid(edda)-type polyamino carboxylic acids were prepared. Their electronic and infrared spectra and thermogravimetric curves were measured in the solid state. The stretching frequencies of the coordinated carboxylate group and the thermal stability of these complexes in the solid state were quite different from those of bis(amino acidato) complexes.
  • Yasuji Nakayama, Shun’ichiro Ooi, Hisao Kuroya
    1976 年 49 巻 1 号 p. 151-155
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    (+)589-Bis(L-ornithinato)cobalt(III) nitrate monohydrate was isolated by ion-exchange chromatography from a reaction mixture of trinitratotriamminecobalt(III) with L-ornithine at pH 9, and was assigned to the cis-(O)trans(Nα)cis(Nδ) isomer on the basis of the absorption and circular dichroism spectra. Then, the geometry of the complex was confirmed by X-ray structure analysis. The red crystal is orthorhombic, with these cell dimensions: a=14.380, b=16.493, and c=6.787 Å. The space group is P212121, and Z=4. The crystal structure was solved by the Patterson and Fourier techniques and was refined by the least-squares method to R 0.099. The Co atom is surrounded by 2 O and 4 N atoms, the former being in cis positions. Each of the L-ornithinato ligands assumes the facial coordination, and the complex cation has an approximate two-fold axis by which the ligand are correlated.
  • Kazuko Y. Matsumoto, Yukiyoshi Sasaki
    1976 年 49 巻 1 号 p. 156-158
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    α-K8SiW11O39·13H2O is cubic with the space group P\bar43m and a=10.654(1) Å; Dm=4.40 g cm−3, Dx=4.42 g cm−3 for Z=1. The crystal contains a discrete SiW11O398− ion, which is almost identical to α-SiW12O404− anion in shape and in size but one tungsten atom and the exterior terminal oxygen atom are absent. The position of the vacant hole could not be located because of the seemingly high symmetry of Td of the polyanion caused by the orientational randomness of the anions. The silicon atom at the center of the polyanion lies on the origin of the cubic lattice and the potassium cations linking α-SiW11O398− ions are at the middle points of adjacent polyanions.
  • Yuzo Yoshikawa
    1976 年 49 巻 1 号 p. 159-162
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The conformational analysis of the [Co(dien)2]3+ and [Co(linpen)]3+ (dien=H2N(CH2CH2NH)2H, linpen= H2N(CH2CH2NH)5H) complexes has been carried out. The former, which can exist in three geometric isomers, was selected as a standard for the determination of several parameters in the strain-energy calculation; they were determined so that the calculated geometries of these isomers were almost the same as those obtained from the crystal structure analysis studies. These results were applied to the strain-energy calculation for the latter, [Co(linpen)]3+, which can exist in four geometric isomers. Further, in three of these isomers, some conformational isomers are possible. From the results of the energy-minimized conformational-analysis calculations of these isomers, it has turned out that the assignment of the structures of the configurational and conformational isomers is possible.
  • Kuniko Yamanouchi, Shoichiro Yamada
    1976 年 49 巻 1 号 p. 163-168
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Cobalt(II), nickel(II) and copper(II) complexes with N-diphenylmethyl-ring-substituted salicylideneiminates (abbreviated as X–Sal–Dpm) have been synthesized, in order to examine the steric and electronic effect of a substituent diphenylmethyl group on the structure of the metal complexes. Compounds of the type M(X–Sal–Dpm)2 and their adducts of the type M(X–Sal–Dpm)2·nL have been isolated in crystals, n being 2 or 4 and L being benzene, acetone or pyridine. Both in the solid state and in non-donor solvents, the complexes Co(X–Sal–Dpm)2 have a tetrahedral configuration, and Ni(X–Sal–Dpm)2 and Cu(X–Sal–Dpm)2 have a square-planar configuration, irrespectively of substituents X. The results so far available seem to indicate that the steric hindrance caused by the substituent diphenylmethyl group against the square-planar configuration of the metal complexes may be smaller than that by isopropyl group.
  • Takeshi Sakurai, Osamu Yamauchi, Akitsugu Nakahara
    1976 年 49 巻 1 号 p. 169-173
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Synthetic and spectroscopic studies have been made on the ternary copper(II) complexes containing two optically active α-amino acids with charged groups in their side chains. Thus, for all combinations of ligands A and B, where A refers to aspartic or glutamic acid and B to arginine, lysine, or ornithine, the mixed ligand complexes, [Cu(L-A)(L-B)] and [Cu(D-A)(L-B)] except [Cu(L-aspartate)(L-ornithine)], were isolated as crystals. Infrared spectra of the isolated complexes suggested the presence of the geometrical isomers. By comparing the observed circular dichroism spectra of the ternary systems with the spectra estimated from those of the corresponding binary systems, the magnitude enhancements were detected for all the Gu(L-A)(L-B) systems, whereas no such enhancement was observed when one of the ligands was L-alanine or L-valine. The spectral behaviors as well as the solid complexes isolated have been interpreted as indicative of the existence of the intramolecular electrostatic bonding between the oppositely charged groups in the side chains of the ligands and their significance as an effective driving force leading to the ternary complex formation.
  • Kiyoshi Okazaki, Shin Sato, Shin-ichi Ohno
    1976 年 49 巻 1 号 p. 174-181
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The binary-encounter collision theory is applied to calculate the G-values for the ionization and excitation of methane, ammonia, and water irradiated by 100 keV electrons. Double collision of the incident electron in a molecule is also taken into account. On the assumption of the occurrence of certain reactions in the systems, the G-values for electrons, various radicals, and several final products were estimated. Some of the results are as follows: the G-values for electrons were 3.60 for methane, 3.56 for ammonia, and 3.00 for water. These values are in fair agreement with the experimental values: 3.6 for methane, 3.8 for ammonia, and 3.3 for water. The calculated G-value for hot hydrogen atoms was about 1.0 for all three compounds. The ratios of the G-value for excitation to that for electrons are 1.1 for methane, 1.5 for ammonia, and 1.7 for water. An estimation was also made of the G-value for the emission of highly-excited hydrogen atoms using reported cross sections. The G-values are 0.1 for methane and ammonia, and 0.2 for water.
  • Noriaki Takahashi, Kyuya Yakushi, Kikujiro Ishii, Haruo Kuroda
    1976 年 49 巻 1 号 p. 182-187
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The solvent-containing modification of benzidine (BD)-tetracyanoquinodimethane (TCNQ) complex is a new type of inclusion compound where solvent molecules are included in the channels of the host lattice formed by hydrogen bonding and charge-transfer interaction between BD and TCNQ. The electrical conductivity at 18 °C is 7×10−10 ohm−1·cm−1 and the activation energy of semiconduction is 0.54 eV in the solvent-free state, but they change to 10−4–10−6 ohm−1·cm−1 and 0.1–0.2 eV, respectively, when an aliphatic solvent is included, and to 10−6–10−9 ohm−1·cm−1 and 0.3–0.5 eV, when benzene or its derivatives is included. By examining the changes of the electrical conductivity and the spin density of BD·TCNQ·[CH2Cl2] system with the pressure change of the ambient dichloromethane vapor, it is concluded that the conductivity of BD·TCNQ·[CH2Cl2] is strongly controlled by the amount of solvent vacancies in the crystal lattice. The correlations between the electrical properties and crystal structures of solvent-containing modifications are discussed.
  • Shigeru Yamashita
    1976 年 49 巻 1 号 p. 188-190
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The primary processes of the photolyses of acetone, methyl ethyl ketone, and methyl vinyl ketone have been studied using a high intensity UV light beam and collision-free photochemical reactor incorporated in the ionsource of a mass spectrometer. Photofragment radicals are directly detected from the mass spectrum of the photolyte flow and the primary processes are determined. Mass spectrum of acetyl radical has been obtained in addition to the mass spectra of hydrocarbon free radicals reported in previous papers. As for the ketones investigated, C–C bond rupture between acetyl and the remainder of the molecule is found predominant in the primary process of the photolysis in the region 290–320 nm.
  • Takakazu Yamamoto, Yoshiyuki Nakamura, Akio Yamamoto
    1976 年 49 巻 1 号 p. 191-197
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The 1H-NMR spectra of NiR2(bpy)(bpy=2,2′-bipyridine; R=CH3, C2H5, and C3H7) and Ni(C2H5)2(bpy)–olefin systems (olefin=acrylonitrile and acrylaldehyde) have been studied in a temperature range from −70 °C to 80 °C. The temperature dependence of the chemical shifts of ethyl and 2,2′-bipyridine protons of Ni(C2H5)2-(bpy) in non-aromatic solvents (acetonitrile, N,N-dimethylformamide, acetone and tetrahydrofuran) is analyzed on the basis of the formation of 1: 1 solvent-solute complex. The formation constant of the 1: 1 comples, K1, and the thermodynamic parameters ΔF1°, ΔH1°, and ΔS1° are given. The NMR spectra of NiR2(bpy) in aromatic solvents show the aromatic induced solvent shifts, and the chemical shifts of CH2 and CH3 of Ni(C2H5)2(bpy) coincide at 76 °C in benzene to give a sharp singlet peak. The 13C-NMR spectrum of Ni(C2H5)2(bpy) in benzene shows a triplet at 10.63 ppm (CH2, J(13C–H)=132 Hz) and a quartet at 15.97 ppm (CH3, J(13C–H)=128 Hz). The formation constant of Ni(C2H5)2(bpy)(olefin), K2, and the thermodynamic parameters, ΔF2°, ΔH2°, and ΔS2° have been obtained from the temperature dependence of the NMR spectra of the Ni(C2H5)(bpy)–olefin systems. The values of the chemical shift differences between CH2 and CH3 (ΔCH2–δCH3) for Ni(C2H5)2(bpy), Ni(C2H5)2-(bpy) (acrylaldehyde), and Ni(C2H5)2(bpy)(acrylonitrile) are −0.30, 0.94 and 0.83, respectively. The increase of the values of Δ by the coordination of the electronegative olefins with nickel is regarded as indicating the increase of the electronegativity of nickel due to the back-donation from nickel to the olefin.
  • Krishnagopal Mandal, T. N. Misra
    1976 年 49 巻 1 号 p. 198-202
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The electronic absorption spectra of a number of α,ω-Di-1-anthrylpolyenes have been studied in solution and in crystals. Three intense and two weak band systems have been observed. The plots of λ2n and ε–n result in a good straight line in lower members. These results suggest that long anthrylpolyenes are not in all-trans form. Highest energy emission and lowest energy absorption bands show good overlap and identical solvent behavior. It has been concluded that in anthrylpolyenes the lowest excited state is an allowed 1Bu type. The terminal anthrylgroup interaction effect is such that 1Ag is not lowered relative to 1Bu in these polyenes. The absorption bands of anthrylpolyenes in the crystalline state could be explained in terms of factor group split components.
  • V. Srinivas Rao, C. Kalidas
    1976 年 49 巻 1 号 p. 203-205
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The effect of addition of small amounts of water on the conductance of hydrogen chloride and hydrogen bromide in diethylene glycol at 25 °C was investigated. The Λ0 of both acids sharply decreases with the addition of water, passes through a minimum at about 1.23 wt% of water and then increases. This was explained on the basis of the changes in the proton jump mechanism due to shift of the proton transfer equilibrium, ROH2++H2O\ ightleftarrowsROH+H3O+. The role of water in this equilibrium was shown to be similar to the protonation of a Hammett indicator base in acid solutions.
  • Miss Dipti, Pushti Prakash Rastogi
    1976 年 49 巻 1 号 p. 206-208
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Electric dipole moments of 4-chloro-2,3-tetra-, penta-, and hexamethylene quinolines have been determined in benzene solution at a frequency of 1 MHz by Guggenheim method. The reported results indicate that these compounds are non-planar and the dipole moment increases with the increase in the size of substituted methylene ring.
  • Sigeru Torii, Masasi Ukida, Hiromichi Kano, Takuya Furuta, Hideo Tanak ...
    1976 年 49 巻 1 号 p. 209-213
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The conversion of α-hydroxyaminoaconates 1a and 1b to α-aminoaconates 2a and 2c was described, involving a novel reduction of the α-hydroxyamines on treatment with p-toluenesulfonyl chloridep–yridine in 62.1–89.5% yields. In the case of the reduction of 1b N-tosyloxy derivative 11b was isolated. α-Amino-γ-butyrolactones 3 and 4 could be obtained by hydrogenation of N-acetates of 2a and 2c. Ammonolysis of 2-hydroxy-2-butenolides 5a and 7a prepared from acid-hydrolysis of 1b also gave α-aminobutyrolactones 6, 8a, 8b, 9, and 10.
  • Charles C. Price, Mitsuhiro Iwasa
    1976 年 49 巻 1 号 p. 214-218
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    While secondary alcohols and NAD+, and ketones and NADH react much slowly than the ethanol–acetaldehyde system in the presence of yeast and liver alcohol dehydrogenases, by starting near equilibrium concentrations, it has been shown that expected thermodynamic equilibria are obtained. With liver ADH, cycloalkanols are remarkably reactive, while with yeast ADH those with six or more carbon atoms in the ring are unreactive. Horse liver ADH shows stereospecificity for 2-octanol, but no stereospecificity for 2-butanol. On the other hand, yeast ADH shows the same stereoselectivity for both alcohols. In the presence of yeast ADH, R(−)-isomers of 2-butanol, 2-octanol and 1-methoxy-2-propanol are not reactive, comparing to the big reactivity of S(+)-isomers of these alcohols, but R(−)-isomer of propylene glycol is also slightly reactive as S(+)-isomer. Further, the reactivity of secondary alcohols with NAD+ in the presence of liver ADH is following, 2-octanol>2-butanol>2-propanol. These results suggest that horse liver ADH is much less sterically hindered at its active site than yeast ADH and that not only the steric factor but also hydrophobic bonding between the end alkyl group of alcohol and the hydrophobic region of enzyme might be another important factor to determine stereospecificity and reactivity of enzyme.
  • Mutsuji Sakai
    1976 年 49 巻 1 号 p. 219-223
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The thermal reaction of citraconic acid (2) in water gives a mixture of products similar to that obtained from itaconic acid (1) in water. After 22 h at 170 °C, the equilibrium composition about 74%, 18%, and 8% 1, 2, and mesaconic acid respectively. At the optimum conditions (170 °C for 3 h), the yield of 1 is 65%. The mechanism of the reaction is discussed.
  • Shuichiro Asao, Naoki Toshima, Hidefumi Hirai
    1976 年 49 巻 1 号 p. 224-230
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The photochemical conversion of N-acetyldiphenylmethyleneamine (I) in toluene to produce an addition product N-(1,1,2-triphenylethyl)acetamide and a hydrogenation product N-(diphenylmethyl)acetamide has been found to increase remarkably by displacement of para-hydrogen of toluene with a halogen (chlorine or bromine). A number of halogenated solvents, especially brominated solvents such as dibromomethane and bromobenzene, also promoted the photoreaction of the imine I with toluene. The extent of the promotion depends on the kind of a halogen atom of the solvent molecule. The reaction rate was accelerated with the number of halogen atoms of the solvent molecule. The conversion rate increased very remarkably when the concentration of bromobenzene increased from 0 to 1 mol/l. The reaction via chemical sensitization by benzophenone, a contaminant in imine I, was shown to be insensitive to the heavy atom solvent. The heavy atom effect can be attributed to an increase in the rate of intersystem crossing from the excited singlet state to the triplet state of the imine I. Imine I in the excited state was confirmed to have a hydrogen abstracting character.
  • Tokuji Miyashita, Takao Aoki, Minoru Matsuda
    1976 年 49 巻 1 号 p. 231-234
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    The optical spectra of the alkali metal salts of arylthiolate anions have been studied in the two aprotic solvents, tetrahydrofuran (THF) and dimethylformamide (DMF). In the former solvent the position of the absorption maxima depends on the size of the counter cations, even at low temperatures (−72 to −76 °C); nearly linear relationships were observed between the inverse of the alkali metal radius (rc) and the wave number of the transition (\ ildeνmax) for both room and low temperatures. The intercepts for the extrapolation of both lines for 1/rc→0 agree with the \ ildeνmax of the ion pairs observed in DMF at room temperature, and the absorption maxima for this solvent are independent of the size of the counter cations. Thus, the existence of contact ion pairs in THF over the temperature range investigated and that of the solvent-separated ion pairs in DMF at room temperature were revealed. In the latter solvent, however, a hypsochromic shift was observed on lowering the temperature. The substituent effect of arylthiolate anions and the solvent effect of dimethoxyethane and dioxane on the absorption maxima are also discussed. From an inspection of optical spectral data it has been suggested that negative charge of arylthiolate anions is localized mainly on the sulfur atom.
  • Katsuo Ohkata
    1976 年 49 巻 1 号 p. 235-244
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    Preparations of anti-4′-substituted 3,4-benzotricyclo[4. 3. 1. 01,6]dec-3-en-2-yl p-nitrobenzoates (1ad) are described. The solvolysis of these esters was examined in 80% aqueous acetone. The rates were relatively high but the sensitivity to substituents on the benzene ring was low in comparison with other secondary systems. It is considered that σ-participation rather than π-conjugation might contribute to the rate accelerative effect. In the presence of a base, 1ad gave anti-alcohol (12ad) (13 to 17%), syn-alcohol (13ad) (31 to 78%), and tert-alcohol (14ad) (5 to 54%). The product distributions are explained in terms of a nonclassical homonaphthalenium cation (24).
  • Hiroshi Yamaoka, Katsuo Ohkata, Terukiyo Hanafusa
    1976 年 49 巻 1 号 p. 245-252
    発行日: 1976年
    公開日: 2006/04/19
    ジャーナル フリー
    A novel secondary cyclopropylphenylmethyl acetate was prepared from a chromone skeleton via homochromone derivatives in order to study solvolytic behavior. Reduction of the cyclopropyl ketone (homochromone) with lithium aluminum hydride in ether to the corresponding secondary alcohol, was found to be highly stereospecific giving only one of the geometrical isomers. The alcohol was converted into its acetate and subjected to solvolysis in 80% acetone–water. The acetate was hydrolyzed at the rate of 3×10−5 s−1 (25 °C) undergoing alkyloxygen fission. This rate constant was as high as the most reactive secondary esters in solvolyses ever reported, and about 20 times as high as the corresponding carbocyclic ester by estimation of the same leaving group. Product studies were undertaken in the presence of sodium hydrogencarbonate, and seven-membered hemiacetal was obtained in good yield. The structural characteristics of the homochromenol ester in the solvolysis are discussed and benzohomopyrylium ion, an extremely delocalized homoaromatic species, is proposed as an intermediate carbocation.
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