Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 50 , Issue 9
Showing 1-50 articles out of 71 articles from the selected issue
  • Hiroshi Fujimoto, Nobuhiro Kosugi
    1977 Volume 50 Issue 9 Pages 2209-2214
    Published: 1977
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    A method of analyzing chemical interactions between two systems is presented and applied to the bimolecular nucleophilic substitution of methylfluoride by fluoride ion. In order to get a clear insight into the mechanisms of chemical interactions, the interacting system has been represented by a combination of various electron configurations of the reactants involved. The matrix elements necessary for the configuration interaction have been obtained by transforming the MO’s of the isolated reactants into a set of orthogonalized functions. The change in the energy and the redistribution of the electrons due to the interaction in the reaction have been calculated by the use of the ab initio (STO-3G) MO’s and have been divided into the Coulomb, exchange, delocalization, and polarization interactions. A comparison of the results with the results of the SCF CI calculations of the composite system has shown the utility of the method in studying weak and moderately strong interactions between two systems.
  • Hisao Negita, Tsuneo Kubo, Michio Maekawa
    1977 Volume 50 Issue 9 Pages 2215-2216
    Published: 1977
    Released: April 19, 2006
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    The 14N nuclear quadrupole resonance (NQR) was studied on three kinds of molecular complexes of urea, such as the urea–hydrogen peroxide complex (H2O2 complex), the urea–sodium chloride–water complex (NaCl complex), and the urea–sodium bromide–water complex (NaBr complex). The 14N quadrupole coupling constants and asymmetry parameters are as follows: |e2Qqh|=3493.8 kHz and η=0.3456 for the H2O2 complex; |e2·Qqh|=3597 kHz and η=0.293 for the NaCl complex, and |e2Qqh|=3636.7 kHz and η=0.2778 for the NaBr complex. From the temperature dependence of the resonance frequencies, it is considered that the hydrogen bonds in the H2O2 complex are stronger than those in the NaCl complex. The electron densities at nitrogen atoms in these complexes were derived from the corresponding NQR parameters, and were compared with those in urea.
  • Kazuo Tokiwano, Kiyoshi Arakawa
    1977 Volume 50 Issue 9 Pages 2217-2222
    Published: 1977
    Released: April 19, 2006
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    A statistical thermodynamic theory of binary liquid mixtures has been worked out on the basis of the equivalent free volume defined without use of lattice model. A liquid mixture is regarded as a mixture of hard spheres immersed in a uniform background potential. The total free energy is expressed as the sum of terms given by the analytical solution of the generalized Percus-Yevick equation for the hard sphere mixture and the term resulting from the uniform background potential. Thermodynamic functions are in a simple form convenient for practical applications. The nature of the equivalent free volume for the mixture which consists of molecules differing in size is elucidated. The energy interaction parameters and excess thermodynamic functions for eight binary mixtures composed of nonpolar molecules are calculated, and the results are discussed.
  • Yoshihiko Sadaoka, Yoshiro Sakai
    1977 Volume 50 Issue 9 Pages 2223-2225
    Published: 1977
    Released: April 19, 2006
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    Bistable switching between two impedance states was observed in copper-phthalocyanine films. The turn-on can be interpreted in terms of the steady thermal breakdown model. The stable high conductivity in the on-state is attributed to the partly carbonized copper-phthalocyanine which was formed by Joule heating along the filamentary paths. The J-V characteristic in the off-state and the threshold-field strength were found to be expressed as JV6|d3.8 and Eth∝1|d0.46 respectively.
  • Shoji Noda, Yasumi Fujii, Hiroshi Yoshida
    1977 Volume 50 Issue 9 Pages 2226-2228
    Published: 1977
    Released: April 19, 2006
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    The proton transfer from ethanol to styrene molecular anion was studied by examining the yield of the anion and α-methylbenzyl radical generated in γ-irradiated 2-methyltetrahydrofuran–ethanol mixed matrix at 77 K by means of optical absorption measurements. The radical yield was found to increase in proportion to the ethanol fraction at the expense of the anion yield. The maximum radical yield, 2.2, was identical with the yield of scavengeable electron in ethanol matrix where no anion was observed. Upon photobleaching the anion was transformed into the radical in the matrix. The transformation efficiency was constant, ca. 0.6, for the ethanol fraction 0.3–0.9. It is concluded that the radical arises from the anion through the proton transfer from ethanol to the β-carbon of vinyl group of the styrene anion. The proton transfer occurs readily only when a specific solvent site around the anion is populated by ethanol molecules. Otherwise, the proton transfer does not occur at all because of the restricted translational motion in the rigid matrix.
  • Fumio Kawaizumi, Makoto Ohno, Yutaka Miyahara
    1977 Volume 50 Issue 9 Pages 2229-2233
    Published: 1977
    Released: April 19, 2006
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    The ultrasonic velocity and density of aqueous solutions of N-methylformamide, N,N-dimethylformamide, and N,N-dimethyIacetamide have been measured at 25 and 35 °C over the entire concentration range. The compressibility, excess compressibility, partial molar compressibility, partial molar volume, and pressure dependence of the partial molar volume have been calculated. The concentration dependences of the velocity and density are highly nonlinear, and the velocity maxima are observed in all the amide solutions at ca. 20 mol%. Minima in the partial molar volume exist in solutions of DMF and DMAA, but not in that of MFA. On taking account of the results for viscosity, the velocity maxima are ascribed to the complex formation, and the minima in the partial molar volume, to the competition between the volume increase due to the complex formation and the volume decrease due to the breaking-down of the water structure. The pressure dependence of the partial molar volume shows that amides and water have strong interactions, even in the low-mole-fraction regions for each component.
  • Yoshio Matsunaga, Nobuhiko Miyajima, Atushi Togashi
    1977 Volume 50 Issue 9 Pages 2234-2238
    Published: 1977
    Released: April 19, 2006
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    Dimorphic forms were isolated for over ten derivatives of 2-anilino-1,4-naphthoquinone, 2-anilino-3-chloro-1,4-naphthoquinone, and 2-anilino-3-bromo-1,4-naphthoquinone carrying substituents on the phenyl ring. One of the two forms exhibits a relatively sharp vibrational band near 3300 cm−1, the other, a relatively broad band at a lower wave number. The spectra in the region from 700 to 1700 cm−1 are often markedly different from each other. In several instances, the two forms are differently colored. This difference is attributed to the appearance of, or a change in the intensity of, an intermolecular charge-transfer absorption band. Not only the dimorphic forms, but also most of the derivatives examined, could be classified into two groups on the basis of the location and the sharpness of the vibrational band appearing in the region from 3150 to 3350 cm−1.
  • Yoshihiko Sadaoka, Yoshiro Sakai, Kohhei Kishi
    1977 Volume 50 Issue 9 Pages 2239-2241
    Published: 1977
    Released: April 19, 2006
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    Threshold switching was observed in anthracene thin films (<3 μm) using a circuit with a high protective resistance. On the other hand, when the protective resistance was small, the switching was erratic and irreproducible. In the latter case, the switching was occasionally accompanied by filamentary damages caused by the excess current focused at the electrically weak spots, and the threshold voltage was poorly dependent on the protective resistance. The threshold-switching characteristics for thin films are interpretable in terms of the transition from the trap-limited SCLC to the trap-filled SCLC. The thermal breakdown model is not adaptable.
  • Hiroo Ogura
    1977 Volume 50 Issue 9 Pages 2242-2246
    Published: 1977
    Released: April 19, 2006
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    H–D exchange reaction between acetylene and deuterium has been investigated in a single-pulse shock tube in the temperature range 1200–1500 K. Empirically, in the C2HD appearance the order with respect to acetylene was 0.25±0.09, and that with respect to deuterium 1.14±0.15. The rate constant of 1.39 th order for the C2HD increase was obtained as; k(cm1.17 mol−0.39 s−1)=(24.4±7.5)×1011exp((−51200±2400)⁄RT). The isotopic distributions of acetylene and hydrogen as determined by mass spectrometry suggest that C2D2 and H2 are formed by the subsequent reactions of C2HD and HD, respectively. A free-radical chain mechanism initiated by the same bimolecular reaction of acetylene, viz. 2C2H2→C4H3+H, as in the pyrolysis and hydrogenation of acetylene was proposed. A steady-state treatment of the proposed mechanism shows that the empirical rate and concentration dependence of the C2HD increase are in line with those of the steady-state rate.
  • Tadaaki Inomata, Momotaro Suzuki
    1977 Volume 50 Issue 9 Pages 2247-2249
    Published: 1977
    Released: April 19, 2006
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    The flames of ethylene and oxygen mixtures (initial pressure, 50–500 mmHg, and ethylene content, 20–40%) were studied, especially for the transition to detonation from deflagration. The flames may roughly be divided into four groups: A, a flame without any shock wave generation; B, a flame with a shock wave generation; C, a flame with many shock waves and much turbulence of the flame, and finally D, the detonation produced by the collision of a flame and a reflected shock wave at the bottom of the tube. The flame transit to detonation from deflagration is a linear relation between the velocities of the flames at the point of detonation and DID, or the distance from the point of ignition to the detonation for all the sorts of flames given above, in spite of several apparent differences.
  • Hiroshi Ueda, Yasushi Kai, Noritake Yasuoka, Nobutami Kasai
    1977 Volume 50 Issue 9 Pages 2250-2254
    Published: 1977
    Released: April 19, 2006
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    The molecular structure of [(π-C5H5)2Rh2{C(C6H5)2}2(CO)] has been determined from three-dimensional X-ray diffraction data (R=0.040 for 2394 reflections). The crystal belongs to the monoclinic system, space group A2/a, with four formula units in a cell of dimensions: a=19.967(5), b=10.343(1), c=16.526(4) Å, and β=123.05(2)°. The molecule has C2 symmetry: the two-fold axis passes through the bridge carbonyl group, being perpendicular to the Rh–Rh bond (Rh–Rh=2.548(1) Å). The diphenylcarbene moieties bridge between rhodium atoms. The planar cyclopentadienyl rings lie 1.94 Å from the nearest rhodium atom and exihibit the usual π-bonded geometry.
  • Hiroshi Nakanishi, Hiroshi Morita, Saburo Nagakura
    1977 Volume 50 Issue 9 Pages 2255-2261
    Published: 1977
    Released: April 19, 2006
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    Near and vacuum UV absorption spectra of acetylacetone were measured in the vapor phase and in several organic solvents at various temperatures. From the temperature dependence of the spectra, the equilibrium constant and enthalpy change between the keto and enol forms of acetylacetone were determined to be 25 at 20 °C and −4.3 kcal/mol, respectively, in the vapor phase. Rydberg excitation bands were observed at 47170 and 53300 cm−1 for the enol form, and ≈52000 cm−1 for the keto form. The estimated values of the quantum defect indicate that the Rydberg orbitals are 3s and 3p. A modified CNDO-CI method was applied to the valence-shell transitions. A weak band observed at ≈34000 cm−1 for the keto form was assigned to the first n-π* transition, and relatively strong bands observed at 38020 and 56800 cm−1 for the enol form, to the first and second π-π* transitions, respectively. Special attention was paid to the charge-transfer (CT) character pertinent to the intramolecular hydrogen bond in the excited states of the enol form. Configuration analysis of the wave functions revealed us that the first π-π* band observed at 38020 cm−1 has the CT character.
  • Masamichi Yamada, Isao Ikemoto, Haruo Kuroda
    1977 Volume 50 Issue 9 Pages 2262-2265
    Published: 1977
    Released: April 19, 2006
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    The oxidation of the surfaces of thin films of perylene, pentacene, violanthrene, and mesonaphthodianthrene on exposure to oxygen or to the air was studied by means of X-ray photoelectron spectroscopy. A perylene film was found to be the least reactive toward oxygen among the above four hydrocarbons. In the cases of pentacene and violanthrene films, a single, broad O 1s peak grew up with time over the period of a few months as the exposure to the air was prolonged. On exposure to oxygen, a mesonaphthodianthrene film exhibited the O 1s spectrum which apparently consisted of two peaks located at the binding energies, 531.0 and 532.9 eV respectively, and the peak at 532.9 eV reduced its intensity irreversibly on heating the film in a high vacuum, suggesting that it was the one associated with a loosely bound oxygen.
  • Mizuka Sano, Takatoshi Narisawa, Mitsunobu Matsuka, Yasumasa J. I&rsqu ...
    1977 Volume 50 Issue 9 Pages 2266-2268
    Published: 1977
    Released: April 19, 2006
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    The electronic configuration of the lowest triplet state for tetrachlorophthalic anhydride (TCPA) was determined to be B2(ππ*) by means of Zeeman spectroscopy. The electronic origin for the singlet-triplet absorption of a TCPA single crystal was found in the region of 421.3 nm at 1.7 K. The first peak in the absorption spectrum was found to possess two components; the one observed at 23726.1 cm−1 corresponds to the transition to the Bu, and the other observed at 23728.5 cm−1 to that to the Au triplet factor group state. The splitting between the two states is 2.4 cm−1.
  • Kazuhiko Ishizu, Kazuo Mukai, Atsuko Shibayama, Kyoko Kondo
    1977 Volume 50 Issue 9 Pages 2269-2271
    Published: 1977
    Released: April 19, 2006
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    ENDOR observations were carried out for several triphenylmethyl derivatives with ortho- or para-methoxy substituents. The alteration of the spin-density distribution caused by steric hindrance, in particular, due to the low symmetrical substitution, was investigated. Using a revised MO parameter proposed by Kulkarni, McLachlan MO calculations were carried out and the twisting angles of the hindered phenyl groups are estimated.
  • Hiroatsu Matsuura, Motomichi Kono, Hiroshi Iizuka, Yoshiki Ogawa, Isse ...
    1977 Volume 50 Issue 9 Pages 2272-2282
    Published: 1977
    Released: April 19, 2006
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    The Raman and infrared spectra of 2-chloro-, 2-bromo, and 2-iodoethyl methyl ethers, CH3OCH2CH2X (X=Cl, Br, and I), were measured for the liquid, glassy, and crystalline states. The gaseous-state spectra of the chloride were also measured. The vibrational frequencies of these molecules were calculated by the use of the force constants transferred directly from unbranched ethers and alkyl halides. The rotational isomerism was studied and the following conclusions were obtained. (1) In the crystalline state, the molecule takes the form having the trans conformation about the CO–CC axis and the gauche conformation about the OC–CX axis. (2) In addition to this form (TG), three other forms (GG, TT, and GT) exist in the gaseous, liquid, and glassy states. (3) In the liquid state, the TG form is the most stable and the GT form is the least stable. (4) The less polar TT and GT forms are more favored and the more polar TG and GG forms are less favored in the gaseous state than in the liquid state.
  • Shigeru Tsunashima, Kuniko Morita, Shin Sato
    1977 Volume 50 Issue 9 Pages 2283-2287
    Published: 1977
    Released: April 19, 2006
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    The isotope effect on the Cd-photosensitized emission of methanol has been investigated using CH3OH, CH3OD, CD3OH, and CD3OD. The relative quenching efficiencies for the 326.1 nm resonance line were 1 : 0.3 : 0 .9 : 0.3 in the order of CH3OH, CH3OD, CD3OH, and CD3OD. The emission intensities from the intermediate complex between an excited cadmium and methanol were also measured. The band-shape was not affected by the substitution of D atoms. The intensity ratio was 1 : 3.1 : 1.1 : 3.1 in the order of CH3OH, CH3OD, CD3OH, and CD3OD, when the incomplete quenching was corrected. These results were explained by the following quenching processes:
    Cd^*+CH_3OH & →Cd···H···OCH_3
    &→Cd···O<_CH_3^H
    where Cd* represents Cd(3P1) and/or Cd(3P0). The D/H kinetic isotope effect on the former process was estimated to be 0.3
  • Hisaya Oki, Yasuko Takahashi
    1977 Volume 50 Issue 9 Pages 2288-2291
    Published: 1977
    Released: April 19, 2006
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    Syntheses by both the isothermal matrix in a solid state and by the usual solution method have been tried for chromium (III) complexes with L- and DL-asparagine, L- and DL-aspartic acid, L- and DL-glutamine, L- and DL-glutamic acid, L- and DL-lysine, and L-ornithine. [Cr(L-aspNH2)3]·2H2O, [Cr(DL-aspNH2)3]·3H2O, (NH4)2[Cr(L-asp)2][Cr(D-asp)2]·4H2O, and (+)[Cr(L-lys)2(NH3)(H2O)]Cl·4H2O were obtained by the matrix method in the solid state, while [Cr(L-aspNH2)3]·2H2O, [Cr(DL-aspNH2)3]·2H2O, and (+)[Cr(L-lys)2(NH3)(H2O)]Cl·4H2O were prepared by the usual solution method. The preparation of chromium(III) complexes with other amino acids was not successful. A new type of complex of chromium(III) containing terdentate DL-aspartic acid and a new mixed chromium(III) complex containing three different ligands (L-lysine, ammine, and aqua) were prepared.
  • Katsuya Tsuji, Kaoru Fujinaga, Tadashi Hara
    1977 Volume 50 Issue 9 Pages 2292-2298
    Published: 1977
    Released: April 19, 2006
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    From a sample subjected to pyrolytic sulfurization in a sealed quartz tube, the evolved gases, carbon disulfide, carbon monoxide, carbon dioxide, carbonyl sulfide, hydrogen sulfide, and a nitrogen molecule were simultaneously estimated. Determination of the atomic ratio between C, H, O, and N was carried out by means of three calibration curves obtained by use of glycine, L-glutamic acid, L-citrulline, and fumaric acid. They are applicable to carboxylic acids and the other compounds, but not to compounds including nitro and/or sulfo groups.
  • Kazuaki Yamanari, Jinsai Hidaka, Yoichi Shimura
    1977 Volume 50 Issue 9 Pages 2299-2303
    Published: 1977
    Released: April 19, 2006
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    Five (bidentate-N,S or -O,S)bis(ethylenediamine)cobalt(III) complexes have been optically resolved and their absolute configurations deduced from their circular dichroism (CD) spectra, where bidentate-N,S or -O,S are NH2(CH2)2S, NH2(CH2)2SR (R=CH3 and C2H5), and CH3S(CH2)nCO2 (n=1 and 2). The chromatographic, CD, and NMR behaviors suggest that the thioether donor atoms are coordinated stereoselectively producing the Δ-(S) or Λ-(R) complexes. Three (terdentate-N,S,O)[1,1,1-tris(aminomethyl) ethane] cobalt(III) complexes of NH2(CH2)2SCH2CO2, NH2(CH2)2S(CH2)2CO2, and L-CH3SCH2CH(NH2)CO2 have been prepared and the complexes of the former two ligands optically resolved; the absolute configurations have been discussed on the basis of the CD spectra.
  • Yasuji Nakayama, Keiji Matsumoto, Shun’ichiro Ooi, Hisao Kuroya
    1977 Volume 50 Issue 9 Pages 2304-2309
    Published: 1977
    Released: April 19, 2006
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    The optical resolution of [Pt(NH3)2(N1-Me-(S)-pn)]Cl2 is effected by using silver di-μ-(+)-tartrato(4−)-bis(antimonate(III)) (Ag2[Sb2(+)-tart2]) as the resolving agent. X-Ray structure analysis of the less soluble diastereoisomeric salt, (+)350-[Pt(NH3)2(N1-Me-(S)-pn)][Sb2(+)-tart2]·H2O, revealed that the asymmetric secondary nitrogen is of the R configuration. The crystal is orthorhombic, with a P212121 space group, a=19.302(7) Å, b=14.791(4) Å, c=7.925(2) Å, and Z=4. The structure was determined from counter intensity data and refined to R 0.049 using the least-squares method for 1955 independent non-zero reflections. The Pt atom has a square-planar coordination with 4 N atoms and both the N–CH3 and C–CH3 groups are equatorial with respect to the chelate ring. The circular dichroism spectrum of R-[Pt(NH3)2(N1-Me-(S)-pn)](ClO4)2, which was obtained from the less soluble di-μ-(+)-tartrato(4−)-bis(antimonate(III)) salt, is presented and discussed on the basis of the distribution of the possible conformers, the relative abundances of which were infered from 13C NMR data.
  • Gi-ichiro Tanaka, Akeo Tomikawa, Hisao Kawamura
    1977 Volume 50 Issue 9 Pages 2310-2316
    Published: 1977
    Released: April 19, 2006
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    In order to establish a reliable and rapid method for the determination of rubidium in biological materials using atomic absorption spectroscopy, chemical interference as well as ionization interference due to co-existing elements and some organic substances was studied. In the presence of potassium of sufficient concentration, most of the interference was found to be negligible. The temperature of the sample solutions proved to be a possible source of error. The process of sample preparation was examined, including a determination of the loss of rubidium in dry ashing. The accuracy and precision of the method was tested by analyzing NBS SRM 1577 Bovine Liver. The rubidium contents of typical biological materials—foodstuffs, human tissues and urine— were determined by the present method and a possible relationship between the rubidium and potassium concentrations is indicated.
  • Kiyoshi Tamura, Shoji Harada, Tatsuya Yasunaga
    1977 Volume 50 Issue 9 Pages 2317-2320
    Published: 1977
    Released: April 19, 2006
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    A temperature-jump study reveals two relaxation phenomena in aqueous nickel (II)–pyridine solutions. One is observed in a metal-rich and low-concentration system, while the other is found only in a ligand-rich and high-concentration system. The relaxation processes are ascribed to the complex formation reactions:
    Ni^2++py\oversetk_1\undersetk_-1\ ightleftharpoonsNi(py)^2+ and Ni(py)_2^2++py\oversetk_3\undersetk_-3\ ightleftharpoonsNi(py)_3^2+
    The rate constants reported are: 3.6×103 M−1 s−1 for k1 and k3, 37 s−1 for k−1 and 760 s−1 for k−3, at 25 °C. The effect of the coordinated pyridine molecules on the reactivity of the metal is discussed.
  • Yoshihisa Matsuda, Yukito Murakami
    1977 Volume 50 Issue 9 Pages 2321-2324
    Published: 1977
    Released: April 19, 2006
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    Bis(3,3′,5,5′-tetramethyldipyrromethenato)manganese(II) in single crystalline and powdered sample states was investigated by means of K-band ESR spectroscopy. The spectral shape for the single crystal depends highly on the angle between the external magnetic field and the crystal axes. Anisotropic parameters D and E evaluated by the simulation method are 0.12±0.01 and 0.032±0.004 cm−1, respectively. These values are considerably larger than those expected for the distorted tetrahedral manganese(II) complexes formed with four equivalent donor atoms. An origin of these large anisotropic parameters has been discussed.
  • Masaaki Kojima, Hiroyuki Yamada, Hiroshi Ogino, Junnosuke Fujita
    1977 Volume 50 Issue 9 Pages 2325-2330
    Published: 1977
    Released: April 19, 2006
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    A complete series often complexes, [Co(en)x(tn)y(tmd)z]3+ (en=ethylenediamine; tn=trimethylenediamine; tmd=tetramethylenediamine) was obtained by preparing four new complexes, [Co(en)(tmd)2]3+, [Co(tn)2(tmd)]3+, [Co(tn) (tmd)2]3+, and [Go(en) (tn) (tmd)]3+. The new complexes were resolved into optical isomers by SP-Sephadex column chromatography. The absorption and circular dichroism spectra of all the complexes were recorded and discussed.
  • Sumio Arakawa, Kazuo Kashiwabara, Junnosuke Fujita, Kazuo Saito
    1977 Volume 50 Issue 9 Pages 2331-2336
    Published: 1977
    Released: April 19, 2006
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    A series of optically active cobalt(III) ammine complexes containing (S,S)-1,3-diphenyl-1,3-propanediamine (dppn) or (S,S)-1,2-diphenyl-1,2-ethanediamine (stien) were prepared. The sign of circular dichroism (CD) of [Co(NH3)4(S,S-dppn)]Br3 depends on solvents in the first absorption band region. The CD magnitude of trans-[Co(NH3)2(S,S-dppn)2]3+ varies significantly with solvent variations in the same energy region. The CD curve of the vicinal effect of (S,S)-dppn derived from the two diastereomers of cis-[Co(NH3)2(S,S-dppn)2]3+ is different from the CD spectra of both [Co(NH3)4(S,S-dppn)]3+ and trans-[Co(NH3)2(S,S-dppn)2]3+. The CD spectra of the (S,S) -stien complexes are insensitive to solvent variations and the vicinal contributions of the (S,S)-stien calculated from a variety of the (S,S)-stien complexes are similar to one another.
  • Toshio Matsumoto, Kunio Mori, Tsutomu Mizoroki, Atsumu Ozaki
    1977 Volume 50 Issue 9 Pages 2337-2340
    Published: 1977
    Released: April 19, 2006
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    In the synthesis of acetic acid by the carbonylation of methanol catalyzed by RhCl3·3H2O or Rh2Cl2(CO)4in the presence of methyl iodide, it was found that ketone solvents, such as acetophenone and benzophenone, keep both the catalytic activity and selectivity high, even at an elevated temperature. The kinetic results in acetophenone are in agreement with the mechanism proposed by Paulik and Roth. The effect of the ketone solvent was discussed by taking account of the competitive oxidative addition of hydrogen iodide with methyl iodide.
  • Okitoshi Abe, Yoko Utsumi, Nobuo Izumiya
    1977 Volume 50 Issue 9 Pages 2341-2345
    Published: 1977
    Released: April 19, 2006
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    An analog of gramicidin S, in which 5,5′-proline residues were replaced by leucine, was prepared in order to investigate the effect of the introduction of hydrophobic side groups on the antibacterial activity and on the conformation. Also the solubility problems encountered during the synthesis of this analog are described. No significant effect was observed on the cyclization reaction by the replacement of 5,5′-proline to leucine residues. This analog exhibited comparable biological activity and the similar conformation to the natural gramicidin S. These studies suggested that the imino groups of 5,5′-proline residues have no significant roles on both antibacterial activity and conformation of this antibiotic.
  • Kiyoshi Hasegawa, Syuzi Hirooka, Hiroshi Kawahara, Atsushi Tanaka, Mas ...
    1977 Volume 50 Issue 9 Pages 2346-2350
    Published: 1977
    Released: April 19, 2006
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    The photobromination of trans-β-styrenesulfonamides in acetic acid at 16–18 °C gave about 75 : 25 mixtures of threo (cis adducts)- and erythro-1,2-dibromo-2-arylethane-1-sulfonamides (trans adducts). A similar photobromination of cis-β-styrenesulfonamide afforded a 33 : 67 mixture of the threo (trans adduct)- and the erthro-dibromides (cis adduct). The diastereomers could be separated by fractional recrystallization. The cis adducts were shown to be formed neither by secondary isomerization nor by (presumably) ionic addition. The trans dehydrobromination of the threo- and the erythro-dibromides with Et3N gave (Z)- and (E)-β-bromo-β-styrenesulfonamides respectively, which underwent further facile dehydrobromination with aqueous 1 M NaOH at 45–50 °C to afford 2-arylacetylene-1-sulfonamides. They were also prepared from (Z)-α-chloro-β-styrenesulfonamide by an analogous procedure.
  • Masato Tanaka, Teruyuki Hayashi, Ikuei Ogata
    1977 Volume 50 Issue 9 Pages 2351-2357
    Published: 1977
    Released: April 19, 2006
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    The product distribution in the hydroformylation of α,β-unsaturated esters (ethyl acrylate, methyl methacrylate, methyl crotonate, and methyl tiglate) catalyzed by Rh2Cl2(CO)4 was studied at 150 °C under 100 atm of synthesis gas (CO/H2=1/1) in the absence or presence of various additional phosphorus ligands. In order to attain a high selectivity of α-formylation (>80%), the addition of shorter methylene-chained diphosphines (R2P(CH2)nPR2, R=phenyl or cyclohexyl, n=2–4) to the reaction system was essential, while the use of Rh2Cl2(CO)4 alone or in combination with triphenylphosphine or a longer diphosphine, Ph2P(CH2)5PPh2, resulted in a very low α-selectivity. The effects of the reaction variables on the product distribution were also examined for acrylate and methacrylate using Ph2P(CH2)4PPh2 and Ph2P(CH2)2PPh2, respectively, as additional ligands.
  • Tadashi Okuyama, Akira Kitada, Takayuki Fueno
    1977 Volume 50 Issue 9 Pages 2358-2361
    Published: 1977
    Released: April 19, 2006
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    The acid- and base-catalyzed isomerizations of Δ5- to Δ4-testosterone have been kinetically studied in aqueous solution. Solvent isotope effects of kH3O+kD3O+=0.69 and kOHkOD=3.1 were obtained. It was thus concluded that the acid-catalyzed isomerization proceeds through rate-determining enolization but the base-catalyzed reaction through rate-determining protonation of an enolate ion. It was found that primary amines efficiently catalyze the isomerization via an iminium ion intermediate. Possible bifunctional catalysis was suggested for the high catalytic activity of polyfunctional primary amines.
  • Toshiaki Miyake, Tsutomu Tsuchiya, Sumio Umezawa, Hamao Umezawa
    1977 Volume 50 Issue 9 Pages 2362-2368
    Published: 1977
    Released: April 19, 2006
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    4′-Deoxykanamycin (9) was prepared from kanamycin via N-benzyloxycarbonylation, 4″,6″-O-cyclohexylidenation, selective benzoylation at 2′,3′, and 2″-hydroxyl groups, 4′-O-mesylation, 4′-iodination, 4′-hydrogenation, and removal of the protective groups. 4′-Deoxykanamycin B (19) was analogously prepared from kanamycin B. 4′-O-Tosyl derivative of kanamycin B was also led to 19. Selective formylation of the 3′-hydroxyl group of a protected kanamycin B derivative with N,N-dimethylformamide-tosyl chloride followed by mesylation of the unstable 3′-O-formyl derivative also led to 4′-deoxykanamycin B. Throughout the syntheses, the 4′-hydroxyl group of the protected kanamycins was found to be least reactive for benzoylation among the 2′,3′,4′, and 2″-hydroxyl groups. The 13C NMR spectrum of 9 was also measured. It was concluded that 4′-deoxygenation of antibiotics structurally related to kanamycin caused the resonances of 13C-6′ downfield shift.
  • Isamu Watanabe, Tsutomu Tsuchiya, Tsuneyuki Takase, Sumio Umezawa, Ham ...
    1977 Volume 50 Issue 9 Pages 2369-2374
    Published: 1977
    Released: April 19, 2006
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    5-O-[3-O-(2-Amino-2-deoxy-α-D-glucopyranosyl)-β-D-ribofuranosyl]-3′-deoxyparomamine was prepared by two different routes. The first route involves glycosylation of a protected N : 6-O-carbonyl-3′-deoxyparomamine with a protected 3-O-(2-amino-2-deoxy-α-D-glucopyranosyl)ribofuranosyl bromide and subsequent removal of the protecting groups. In the second route, 1-N : 6-O-carbnyl-3′-deoxyparomamine was glycosylated with a protected ribosyl bromide having 3-O-benzylthiocarbonyl group to give a pseudotrisaccharide and, after de-3-O-benzylthiocarbonylation, the product was further condensed with a protected 1-bromide of 2-amino-2-deoxy-D-glucose. This synthesized lividomycin B analogue showed only very weak antibacterial activity and the role of the 6'″-amino group of lividomycin in the action was suggested.
  • Mitsuhiro Kinoshita, Yoshiharu Suzuki
    1977 Volume 50 Issue 9 Pages 2375-2378
    Published: 1977
    Released: April 19, 2006
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    Streptolidine lactam (3) present in streptothricin antibiotics was stereospecifically synthesized. 3,4-Anhydro-1,2 : 5,6-di-O-isopropylidene-D-iditol (4) was converted into the 3,4-bis(benzyloxycarbonylamino)-3,4-dideoxy-D-mannitol derivative 7 via the 3,4-diazido-3,4-dideoxy-D-mannitol derivative 6. De-O-protection of 7 followed by two-stage oxidation with periodate-bromine afforded 2,3-bis(benzyloxycarbonylamino)-2,3-dideoxy-D-arabono-1,4-lactone (8), which was transformed into the azide lactone 9. Selective hydrogenolysis of 9 with Raney Ni gave the N-protected amino sugar lactam 10. O-Tetrahydropyranylation of 10 followed by hydrogenolysis afforded the O-protected amino sugar lactam 12. Treatment of 12 with cyanogen bromide in water gave the O-tetrahydropyranylated streptolidine lactam 13, which on mild acid hydrolysis afforded 3 (hydrochloride). The amino sugar lactam 14 obtained by hydrogenolysis of 9 with palladium black was also treated with cyanogen bromide to yield 3 (hydrobromide). Acid hydrolysis of 3 gave streptolidine (2) (dihydrochloride) identical with that derived from the antibiotics.
  • Masao Okubo
    1977 Volume 50 Issue 9 Pages 2379-2384
    Published: 1977
    Released: April 19, 2006
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    The reaction in which 4′-methoxy and 4′-cyano substituents on 2,3,5,6-tetramethylbenzophenone are effectively replaced by benzyl- and t-butylmagnesium chloride was examined by means of ESR measurements. Both the original and the “replaced” ketyl radicals were identified, and an electron-transfer mechanism similar to that of SRN-type reactions was proposed. Some sterically hindered αβ-enones were also found to form detectable amounts of ketyl radicals. The factors governing the production ratio of the normal and the conjugate adduct were discussed.
  • Atsuyosi Ohno, Hiroyuki Yamamoto, Tadashi Okamoto, Shinzaburo Oka, Yut ...
    1977 Volume 50 Issue 9 Pages 2385-2386
    Published: 1977
    Released: April 19, 2006
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    Kinetics for the reduction of methyl benzoylformate (1) with N-α-methylbenzyl-1-propyl-1,4-dihydronicotinamide (2) in the presence of magnesium perchlorate in acetonitrile at 25 °C has been studied. The reaction follows first-order in 1, first-order in 2, and zero-order in magnesium ion when [2]<<[1], [Mg(ClO4)2]. When [2]= [Mg(ClO4)2]<<[1], the kinetics is best explained by Eqs. 6 and 7. The results indicate that 2 and magnesium ion form a complex, which reacts with 1 at the rate-determining step. It is concluded that magnesium ion activates 2 to promote the release of an electron.
  • Haruhiko Aoyagi, Nobuo Izumiya
    1977 Volume 50 Issue 9 Pages 2387-2390
    Published: 1977
    Released: April 19, 2006
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    Two hexapeptides, H–Arg–Gly–Pro–Phe–Pro–Ile–OH (1a) and H–Arg–Pro–Gly–Phe–Pro–Ile–OH (1b), have been proposed for a factor inducing sexual agglutination in the yeast and were synthesized by a conventional method. Compound 1a was completely identical with the natural peptide in thin-layer chromatography, mass spectrometric measurements, and biological assay on agglutination. Compound 1a showed the same biological activity as 1a though distinct differences in the chemical data were observed. Strong bitterness of the 1a and 1b was discovered.
  • Kiyoshi Nakagawa, Shoji Iwase, Yasutaka Ishii, Sawako Hamanaka, Masaya ...
    1977 Volume 50 Issue 9 Pages 2391-2395
    Published: 1977
    Released: April 19, 2006
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    Die zwei Isomere des Dicyclopentadiens und vier Isomere des Tricyclopentadiens werden isoliert und ihre 13C-NMR-Spektren werden vorgelegt, wobei die Trimerisationsstufe des Cyclopentadiens systematisch in allen Einzelheiten behandelt wird. Die 13C-NMR-Spektren von Oligomeren des Cyclopentadiens werden durch Vergleich mit Spektren von Vergleichssubstanzen zugeordnet. Es ist beachtenswert, dass zwei neue Stereoisomere des Tricyclopentadiens isoliert und nachgewiesen werden.
  • Masao Nakamura, Yoshiro Ogata
    1977 Volume 50 Issue 9 Pages 2396-2399
    Published: 1977
    Released: April 19, 2006
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    Photolyses of alkylbenzenesulfonic acids, such as benzene-, p-toluene-, and p-ethylbenzenesulfonic acids, in aqueous solution by sodium hypochlorite have been studied. In the presence of a large excess of hypochlorite, benzenesulfonic acid is completely photolyzed to give carbon dioxide and sulfuric acid. Irradiation of an equimolar mixture of substrate and hypochlorite in an aqueous solution yields the corresponding alkylbenzene, alkylphenol, arylalkyl alcohol and arylalkylaldehyde, some of which may be produced by an attack of the oxidant on alkyl chain. In some cases, small amounts of diaryl sulfones and chlorinated compounds are also detected.
  • Seiji Shinkai, Toyoki Kunitake
    1977 Volume 50 Issue 9 Pages 2400-2405
    Published: 1977
    Released: April 19, 2006
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    The influence of micelles on the reaction of isoalloxazines and 1,4-butanedithiol(BDT) was studied. The pKa of BDT was lowered by 0.3 pK unit in the presence of the hexadecyltrimethylammonium bromide(CTAB) micelle, indicating the formation of “hydrophobic ion pairs.” The apparent second-order rate constant for the reaction of 3-methyl-10-ethylisoalloxazine and BDT increased by 18-fold on addition of CTAB(3 mM). The UV-visible spectrum of 3-hexadecyl-10-butylisoalloxazine in the presence of the CTAB micelle was similar to that in organic solvents, the rate being enhanced by more than 400-fold as compared with that in a nonmicellar system. Anionic(SDS) and nonionic(Brij-35) micelles suppressed the reaction. The results show that the flavin oxidation of dithiol is facilitated by the environments of the CTAB micelle.
  • Shoichiro Ozaki, Yoshimasa Ike, Haruo Mizuno, Katsutoshi Ishikawa, Har ...
    1977 Volume 50 Issue 9 Pages 2406-2412
    Published: 1977
    Released: April 19, 2006
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    The toxicity and tumor affinity of 5-fluorouracil (1) have been modified by the introduction of a carbamoyl group. Carbamoylation by three general methods were studied extensively: (i) The reaction of 1 with isocyanate, (ii) the reaction of 1-chloroformyl-5-fluorouracil with amine, and (iii) the reaction of 1 with carbamoyl chloride. These three methods usually give 1 -carbamoyl-5-fluorouracils (2). 3-Carbamoyl-5-fluorouracils were not obtained by any method. The 2 substances take a hydrogen-bonded structure in chloroform, a non hydrogen-bonded structure in DMSO at 80 °C, and mixed structures in DMSO at 25 °C. Thirty-six homologues shown by 2 were prepared all of these compounds showed antitumor activity. Of them, 1-hexylcarbamoyl-5-fluorouracil (HCFU) appeared to be the most promising antitumor agent when administered orally in that HCFU retains well balanced lipo- and hydro-philicity, is stable in acid in the stomach, and moreover, decomposed moderately in a tumor. Isocyanate was obtained from the reaction of amine with trichloromethyl chloroformate (TCF) by simply heating these two reagents in toluene; this offers a convenient new method for synthesizing isocyanate from amine. Several new isocyanate were obtained from amino acids.
  • Akira Yasutake, Haruhiko Aoyagi, Nobuo Izumiya
    1977 Volume 50 Issue 9 Pages 2413-2416
    Published: 1977
    Released: April 19, 2006
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    Authentic peptides, α- and ω-isomers of L-aspartyl (or L-glutamyl)-L-phenylalanine (or L-tyrosine) methyl ester, were synthesized by conventional methods. Among these eight peptides, α-L-glutamyl-L-phenylalanine methyl ester showed the tendency to convert to the corresponding dipeptide anhydride even under mild conditions. The experiments on a small column of Dowex 50 cation exchange resin were carried out with a model mixture composed of the α- and ω-isomers, and the optimum conditions for the complete separation of both isomers were determined. A synthetic mixture composed of the α- and ω-isomers was prepared readily through the coupling of benzyloxycarbonyl-L-aspartic acid (or glutamic acid) anhydride with L-phenylalanine (or L-tyrosine) methyl ester and subsequent hydrogenation. The synthetic mixture was separated by the use of a large ion exchange column and each isomer was obtained in a good yield.
  • Noboru Matsumura, Hiroshi Kawai, Yoshio Otsuji, Eiji Imoto
    1977 Volume 50 Issue 9 Pages 2417-2419
    Published: 1977
    Released: April 19, 2006
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    The reactions of 1-methoxycarbonyl-2-imidazolidinone, 3-acetyl-1-methoxycarbonyl-2-imidazolidinone and 1-methoxycarbonyl-cis-perhydrocyclopenta[d]imidazol-2-one with butylamine were studied in the absence and presence of various metal ions. Certain bivalent ions such as Mg2+, Ca2+, and Mn2+ enhanced an electrophilic reactivity of the methoxycarbonyl group and facilitated the transfer reaction of this group to butylamine, especially when the imidazolidinone moiety of substrates bears the methoxycarbonyl group at one N-position and a hydrogen atom at the other N-position. Whereas monovalent ions such as Na+ and Ag+, and bivalent ions such as Zn2+ and Cu2+, had no appreciable effect on the reactivity, and exhibited almost the same reactivity patterns as those observed in the reactions in the absence of metal ions. A possible explanation is given in terms of the stability of coordination complexes which are formed by the interaction between the imidazolidinone moiety of substrates and added ions.
  • Yukito Murakami, Junzo Sunamoto, Hiroki Kondo, Hiroshi Okamoto
    1977 Volume 50 Issue 9 Pages 2420-2427
    Published: 1977
    Released: April 19, 2006
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    The catalytic efficiency of 10-amino[20]paracyclophane in the deacylation of p-nitrophenyl carboxylates was investigated in 10.9 or 20.8% (v/v) aqueous ethanol at μ=0.10 (KCl). The present catalyst exhibited marked catalytic effects not only in the free amine but in the ammonium form. The observed saturation-type kinetics is consistent with a reaction mechanism which involves pre-equilibrium complexation between the aminoparacyclophane and the substrate at a 1 : 1 molar ratio, followed by pseudo-intramolecular catalysis effected by the amino group of the macrocycle. Studies on the inhibition effect by 1-dodecanol and the modification of the catalyst by 2,4-dinitrofluorobenzene confirmed the effective binding ability of the present paracyclophane toward hydrophobic substrates. The free amine form of the catalyst acted as an effective nucleophile to give the acylated aminoparacyclophane as confirmed by the product analysis. On the other hand, the protonated amine form also enhanced the ester degradation, retaining a turnover behavior. On the basis of the kinetic solvent isotope effect and the exceedingly minor kinetic effect of [10-oxo[20]paracyclophan-22(23)-ylmethyl]trimethylammonium chloride in the ester degradation in the neutral pH region, a plausible reaction mechanism has been discussed.
  • Jun-ichiro Take, Haruyuki Kawai, Yukio Yoneda
    1977 Volume 50 Issue 9 Pages 2428-2431
    Published: 1977
    Released: April 19, 2006
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    A new method has been proposed for measuring the surface acidity of solid acids. The method involves the titration of a solid acid with the indicator itself in a nonpolar solvent; it determines the number of acid sites from the amount of the indicator chemisorbed at saturation. The titration of silica-aluminas with 4-anilinoazobenzene (pKa=1.5) itself yielded an acid content smaller than the butylamine titration method with the same indicator. This difference in acid content was ascribed to the difference in the base strength of the titrants. Similarly, titration with trans-azobenzene (pKa=−2.9) itself produced an acid content smaller than that with 4-anilinoazobenzene itself.
  • Masaharu Tsuji, Teiichiro Ogawa, Yukio Nishimura, Nobuhiko Ishibashi
    1977 Volume 50 Issue 9 Pages 2432-2437
    Published: 1977
    Released: April 19, 2006
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    Upon the impact of an electron beam (100–450 eV) on PhOH, PhOCH3, PhOC2H5, PhCOCH3, and (Ph)2CO at low pressures, the S1 emission of the parent molecule (not from PhCOCH3 and (Ph)2CO) and the photo-emissions from such fragments as H, CH, CO, CO+, and OH were observed in the 200–520 nm region. It was concluded that the S1 emission of the parent molecule originates through both the S0→S1 and S0→S2 (cascade)→S1 excitation processes and that the direct excitation into the lower vibronic levels of S1 is responsible for the appearance of the vibrational structures. Most excited species including CO+(A) from PhOH were confirmed to be primarily produced; however, CO+(A) from PhOCH3, PhOC2H5, and PhCOCH3, and CO(b) from PhCOCH3 were found to be produced competitively through one-electron and two-electron excitation processes in relation to the intensity measurements. The relative contribution of the two-electron excitation process in producing CO+(A) increased with a larger substituent, and it was larger than that for CO(b) in PhCOCH3.
  • Yoshiya Kera, Keiji Kuwata
    1977 Volume 50 Issue 9 Pages 2438-2441
    Published: 1977
    Released: April 19, 2006
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    To obtain information on the arrangements of the VOSO4 phase in the surface layer of the V2O5 single crystal, the angular dependencies of an asymmetric ESR spectrum which has been found in the crystal under the conditions of SO2 oxidation and assigned to the VOSO4 phase were examined in detail. Two types of the angular dependency of the spectrum on the static magnetic field were clearly differentiated from each other. In the main spectrum, the direction of g⁄⁄ was completely consistent with the b-axis of the V2O5 crystal, while, on the other hand, in the minor spectrum, it took rather random orientations. From comparisons of the crystal structures between V2O5 and VOSO4, it was deduced, preliminarily, that the α-VOSO4 phase with a layer structure, was regularly aligned along the layer of the V2O5 lattice and that the β-VOSO4 phase without a layer structure took a relatively random orientation to the lattice.
  • Isao Kamiya, Takashi Sugimoto
    1977 Volume 50 Issue 9 Pages 2442-2446
    Published: 1977
    Released: April 19, 2006
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    A number of ketones and carboxylic acids have been examined for direct and indirect chemiluminescence with 9,10-diphenylanthracene and 9,10-dibromoanthracene by air oxidation. From the finding that the efficiency of the chemiluminescence was dramatically influenced by the class of the C–H bond adjacent to the carbonyl group, it was concluded that the molecules with a –COCH– group surely give an excited product during air oxidation in alkaline aprotic solvents. The reaction scheme was consistent with the evidence that most simple carboxylic acids exhibited no chemiluminescence, probably because the C–H bond adjacent to the carboxyl group is no more acidic, but keto acids exhibited emission. In several compounds, however, the chemiluminescent reaction was retarded by other functional groups.
  • Isao Kamiya
    1977 Volume 50 Issue 9 Pages 2447-2450
    Published: 1977
    Released: April 19, 2006
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    An attempt has been made to evolve the kinetic scheme in order to evaluate the yields (φreact*) of excited triplet products generated from the air oxidation of 3-methyl-2-butanone (1) and isopropyl phenyl ketone (2). Expressions for the total light emission and quantum yield of the indirect chemiluminescence (CL) can be derived, from which the rates of energy transfer from excited triplet products to singlet 9,10-dibromoanthracene (DBA), kTS, and φreact* were determined on the basis of the CL intensity measured for various DBA concentrations. The values of kTS from 1 and 2 (4×108 and 1×109 1 mol−1 s−1) are in fair agreement with the values proposed by several investigators who measured the indirect CL from the thermal cleavage of 1,2-dioxetanes. The markedly small φreact* values (1×10−5 and 1×10−3) result from the fact that the CL arises from a minor reaction.
  • Kazuaki Yamanari, Jinsai Hidaka, Yoichi Shimura
    1977 Volume 50 Issue 9 Pages 2451-2458
    Published: 1977
    Released: April 19, 2006
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    Two kinds of mixed type cobalt(III) complexes, [(2-aminoethylthio)acetato](L-methioninato)cobalt(III) chloride and [3-(2-aminoethylthio)propionato](L-methioninato)cobalt(III) chloride, have been prepared and chromatographically separated into seven and eight isomers, respectively. The characterization of isomers based on their electronic absorption and 1H NMR spectra leads to the conclusion that there have been obtained four pairs of diastereomers due to the sulfur chirality of the coordinated L-methioninate. The circular dichroism spectra of isomers have been measured and discussed in relation to the absolute configurations. The vicinal CD contribution due to the chiral sulfur atom of L-methioninate has been estimated by applying an additivity rule for the three diastereomeric pairs.
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