Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 51 , Issue 7
Showing 1-50 articles out of 66 articles from the selected issue
  • Hiroyuki Shinohara, Akira Imamura, Takahiro Masuda, Masaharu Kondo
    1978 Volume 51 Issue 7 Pages 1917-1922
    Published: 1978
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    The electrophilicity of the hydroxyl radical in hydrogen abstraction from methane was studied by the CNDO/2 method. The stabilization energy due to the delocalization of the electrons (SEDE) between methane and the radical at a close distance was calculated. The electrophilicity defined by the SEDE from methane to the hydroxyl radical was larger than the nucleophilicity defined by that from the hydroxyl radical to methane. This result is consistent with the electrophilicity observed in hydrogen abstraction by the hydroxyl radical from a series of substituted methanes. For sulfhydryl radical, the electrophilicity was also suggested by the calculation for hydrogen abstraction from methane. The calculations were also carried out for various radicals which have low electron affinity (hydrogen atom and methyl radical), and the SEDE from methane to the radical was found to be large compared with that from the converse case.
  • Kenji Honma, Inosuke Koyano, Ikuzo Tanaka
    1978 Volume 51 Issue 7 Pages 1923-1926
    Published: 1978
    Released: April 19, 2006
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    The effect of the internal and translational energies of ionic reactant on the rates of the reactions C3H4++NH3→C3H3+NH4+ has been examined by producing the reactant ions from propyne, allene, and cyclopropene by photoionization at various wavelengths. The translational energy was varied by changing the repeller voltage in the ionization chamber. The cross sections for all the reactions decreased with an increase in the internal energy at all the translational energies studied. The results have been explained in terms of the complex mechanism.
  • Yasumichi Matsumoto, Hiroshi Yoneyama, Hideo Tamura
    1978 Volume 51 Issue 7 Pages 1927-1930
    Published: 1978
    Released: April 19, 2006
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    The reaction mechanism of the O2 reduction at LaNiO3 was studied by using a rotating ring-disc electrode, which consists of a LaNiO3 disc and Pt ring electrodes. It was found that the O2 was completely reduced to OH on the Hoare path. Oxygen vacancies seem to be required in the oxide surface for reduction of adsorbed O2H to OH.
  • Tsutomu Takagi, Masayoshi Oiwa
    1978 Volume 51 Issue 7 Pages 1931-1936
    Published: 1978
    Released: April 19, 2006
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    The hydrogen-migration mechanism of the fragmentation of the methyl formate under electron impact has been discussed from the standpoint of the all-valence electron semi-empirical SCF-MO theory (CNDO/2-Unrestricted Hartree Fock), assuming the following models:
    (Remark: Graphics omitted.)
    The model for the hydrogen migration and the possible driving force are presented based on the partition method. The localized MO calculation has been carried out, by the “energy localization” method of the MINDO MO’s, for the origin and the terminus of the migration as an aid to the understanding of the migration. Although the possibility of the hydrogen migration in other models can not always be neglected, the hydrogen migration via Model 1 may be estimated to be energetically favorable, judging from the variation in the total energy and the conformation influence.
  • Goro Wada, Emiko Nagao, Nagako Kawamura, Kyoko Kinumoto
    1978 Volume 51 Issue 7 Pages 1937-1941
    Published: 1978
    Released: April 19, 2006
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    The temperature of the maximum density (TMD) of aqueous solutions was measured for twenty complex ions of transition metals. From the degrees of depression of TMD, Despretz’s constant kionD and the constant of excess depression of mixing Δkion were determined. These constants along with Bion coefficient of viscosity give us information on the structure of water in the vicinity of ions. [Co(H2O)6]2+, [Ni(H2O)6]2+, [Cu(H2O)6]2+, and [Zn(H2O)6]2+ are electrostrictive structure-breakers in the natural order of Irving-Williams, Co(II)<Ni(II)<Cu(II)>Zn(II). Of the complexes [Co(NH3)6]3+, [Co(en)3]3+, and [Co(pn)3]3+, the pn-complex is the strongest hydrophobic structure-maker due to the hydrophobic nature of its aliphatic constituent. Both [Fe(CN)6]3− and [Co(CN)6]3− are fairly strong electrostrictive structure-breakers, while [Fe(phen)3]2+, [Co(phen)3]2+, and [Co (phen)3]3+ are clathrate-like structure-makers. The EDTA and CyDTA complex ions of Co(II), Ni(II), Cu(II), and Zn(II) show no significant difference in kionD, the situation being complicated by the hydrophobicity of the ligands and the radius effect of the complex ion. The actions of ions as structure-makers should be classified into three categories; electrostrictive, hydrophobic (iceberg formation), and hydrophobic (clathrate-like structure formation). The characteristic influence of the structure-making nature on kionD, Δkion, and Bion is discussed.
  • Kensho Sagisawa, Hideko Kiriyama, Ryôiti Kiriyama
    1978 Volume 51 Issue 7 Pages 1942-1945
    Published: 1978
    Released: April 19, 2006
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    The 1H and 35Cl relaxation times in NaAuCl4·2H2O have been measured at temperatures between 79 and 350 K. The 1H T1 data revealed that the water molecule of crystallization reorients about its C2 axis with an activation energy of 26 kj mol−1. The 35Cl T1 values of the four NQR absorptions indicated that the reorientation of the water molecule makes no important contribution to the chlorine T1 in spite of the hydrogen bonds between them. A brief analysis of the 35Cl T1 led to a frequency of 58 cm−1 for the torsional vibration of the AuCl4 ion.
  • Kunimasa Fukuda, Akio Urushiyama
    1978 Volume 51 Issue 7 Pages 1946-1950
    Published: 1978
    Released: April 19, 2006
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    The crystal absorption spectra of some halogenoammine complexes of Co(III) were measured at liquid helium temperature. The vibrational fine structures observed for the spin-allowed ligand field bands were interpreted in terms of a vibronic intensity mechanism in comparision with the vibrational frequencies of the skeletons. It was found that all the vibrational fine structures consist of the uniquantal progression of totally symmetric Co–N stretching vibration. This suggests that the equilibrium Co–N distances of these complexes are elongated in the ligand field electronic excited state as compared with those in the ground state.
  • Hironobu Umemoto, Shigeru Tsunashima, Shin Sato
    1978 Volume 51 Issue 7 Pages 1951-1955
    Published: 1978
    Released: April 19, 2006
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    A phase-shift method was used to study the cadmium-photosensitized luminescence of ammonia and some aliphatic amines. The phase angles between the resonance fluorescence at 326.1 nm and the luminescence from the excited complexes have been measured at various modulation frequencies (10–99 kHz). The results could not be explained by means of the reaction mechanism proposed by analogy with the mercury-photosensitized luminescence of ammonia. In order to obtain a consistency, the equilibrium between the unstabilized and stabilized complexes: CdNH3+NH3\ ightleftarrowsCdNH3*+NH3, had to be taken into account. The reverse reaction was not necessary to explain the results of the mercury-photosensitized luminescence of ammonia. This discrepancy may be ascribed to the difference in the energy gap between the 3P1 and 3P0 states of mercury and cadmium.
  • Tatsuo Matsushima
    1978 Volume 51 Issue 7 Pages 1956-1960
    Published: 1978
    Released: April 19, 2006
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    The kinetics of the CO oxidation has been studied on polycrystalline platinum at various partial pressures, total pressures, and temperatures; 0.1<PcoPo2<5, 10−6<P<10−3 Pa, and 300<T<900K. The reaction was first-order in CO and zero-order in O2 for low pressures of CO, while it was inhibited by CO above a certain critical CO pressure, which increased with an increase in the O2 pressure and temperature. Above that CO pressure, the reaction was first-order in O2 and negative-order in CO. The amount of CO adsorbed was determined during the reaction with a flash-desorption technique. Above the critical CO pressure it was almost equal to that determined in the CO/Pt equilibrium system. It decreased sharply around the CO pressure and was very small at lower pressures. The kinetic behavior can be explained in terms of a Langmuir-Hinshelwood process and a change in the rate-limiting step.
  • Jerzy Kroh, Shoji Noda, Kiyomi Yoshida, Hiroshi Yoshida
    1978 Volume 51 Issue 7 Pages 1961-1964
    Published: 1978
    Released: April 19, 2006
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    Studies on electron trapping in 8 and 18 mol·dm−3 NaOH glassy ices were performed by means of 4 K γ-irradiation technique. The optical absorption spectra of et were found to be considerably red-shifted and broader compared with the spectra in the ices irradiated and examined at 77 K. This trend was more pronounced for the concentrated sample. The red part of the broad spectra was removed either by photobleaching with light of λ>800nm at 4 K or by thermally annealing at 77 K. These results, combined with electron spin resonance data, lead to the conclusion that the shallow electron traps responsible for the red part of the spectra are formed with the participation of Na+ cations in the alkaline ices.
  • Tatsuo Masuda, Hitofumi Taniguchi, Kazuo Tsutsumi, Hiroshi Takahashi
    1978 Volume 51 Issue 7 Pages 1965-1969
    Published: 1978
    Released: April 19, 2006
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    The differential heats of adsorption of ammonia on several solid acids were measured by means of a twin conduction type microcalorimeter, and surface acid strength distribution and acidity were evaluated. Silica–alumina showed very high initial heats which were not observed in decationated zeolite and silica–magnesia. The acidity of zeolite was about 6 times as high as that of silica–alumina, showing very charactristic acid site distribution at 100 kJ/mol of adsorption energy, and suggesting the existence of homogeneous acid sites. The surface water modified surface acidic nature transforming strong acid sites into weaker ones. The poisoning of acid sites of silica-alumina with alkali occurred preferentially at sites on which adsorption energy of ammonia was 96–105kJ/mol.
  • Hitofumi Taniguchi, Tatsuo Masuda, Kazuo Tsutsumi, Hiroshi Takahashi
    1978 Volume 51 Issue 7 Pages 1970-1972
    Published: 1978
    Released: April 19, 2006
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    The acid strength distribution of silica–alumina catalyst (alumina content 13 wt%) evacuated at 400 °C for 5 h was determined by the measurement of heat of adsorption of ammonia, and compared with that determined by amine titration by use of a series of Hammett indicators. The heats of adsorption of ammonia on silica–alumina poisoned with Hammett indicators were also measured in order to obtain the relation between the dissociation constant of the acid (pKa) and the heat of adsorption. When the dissociation constants of acid were equal to −5.6 and +3.3, the differential heats of adsorption of ammonia were observed to be 76.1 and 55.1 kJ/mol, respectively. The number of acid sites calculated from the heat vs. adsorbed amount curve was found to be about twice as large as that determined by amine titration. The discrepancy is discussed.
  • Tsunetaka Sasaki, Hiroshi Amano, Hitoshi Suzuki
    1978 Volume 51 Issue 7 Pages 1973-1976
    Published: 1978
    Released: April 19, 2006
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    Using gel columns of Sephadex G 50 Fine and CPG gel, gel filtration studies were made of the sodium dodecyl sulfate (SDS)–urea system. The results demonstrated that both the CMC and the elution volume of SDS were increased by the addition of urea. The increase of the elution volume indicates the decrease in micellar size, and this coupled with the increase of CMC indicates the increased difficulty of micelle formation by the addition of urea. The direct interaction between SDS and urea was also examined by the gel filtration method and such interaction was confirmed to be absent both below and above the CMC of SDS. Furthermore, the micellar weight of SDS was estimated by the gel filtration method and values of 23000 and 11000 were obtained for SDS solutions containing 0 and 3 mol dm−1 urea, respectively.
  • Kazumitsu Kojima, Kiyoshi Arakawa
    1978 Volume 51 Issue 7 Pages 1977-1981
    Published: 1978
    Released: April 19, 2006
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    Pair correlation functions and structure factors of molecular fluids were computed, based on the reference interaction site model (RISM) integral equation coupled with the Percus-Yevick (PY) and the hyper-netted chain (HNG) approximations. The system considered is a fluid of diatomic molecules consisting of two identical spheres of diameter a with each center located at a distance L(L<σ). The total potential energy for the molecular fluid is assumed to be the sum of pair potentials of the Lennard-Jones type. It is shown that the pair correlation functions calculated are in agreement with results of molecular dynamics studies. The structure factors calculated by using two kinds of approximations (PY and HNG) are found to deviate from each other for small values of k(wave vector). Discussions are given on the behavior of the structure factors, S(k). The rise of S(k) at small k is ascribed to the effect of attractive forces between molecules.
  • Yoji Hara, Malcolm F. Nicol
    1978 Volume 51 Issue 7 Pages 1982-1984
    Published: 1978
    Released: April 19, 2006
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    Mid-infrared (900–1600 cm−1), visible absorption spectra and electrical resistance of bis(benzil dioximato)platinum(II) [abbreviated as Pt(bz)2], bis(dimethylglyoximato)platinum(II) [Pt(dmg)2], bis(1,2-cyclohexanedione dioximato)platinum(II) [Pt(cd)2], and bis(pyruvaldehyde dioximato)platinum(II) [Pt(pa)2] have been measured at high pressures. A decrease of the C=N frequency by −40.0 cm−1, with reduction of the dπ→π* optical transition intensity by \simeq14%, show that [Pt(bz)2] enhances thermally its dπ→π* electron transfer at high pressures up to 35 kbar. No such changes are observed for [Pt(dmg)2], [Pt(cd)2], and [Pt(pa)2]. This backbonding causes [Pt(bz)2] to release the instability, due to increasing overlapping of the electron clouds around Pt(II) at high pressures, that is the cause of the resistance minimum.
  • Yoji Hara, Malcolm F. Nicol
    1978 Volume 51 Issue 7 Pages 1985-1987
    Published: 1978
    Released: April 19, 2006
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    Relative to the related compounds 2,2′-binaphthyl (I) and 2,2′-dimethoxy-1,1′-binaphthyl (II), the pressure dependence of the fluorescence of crystals of 1,1′-binaphthyl (III) is complex. Compression to 30 kbar at room temperature shifts the 1La fluorescence spectra of all three compounds to longer wavelength but, for I and II does not change the intensity profile, except for some 0-0 reabsorption. For III, this red shift characteristic of 1La fluorescence spectra is dominated by growth of new bands about 3.5 to 5.0×103 cm−1 to lower energy. Similar new bands are observed when 1,1′-binaphthyl crystals are compressed at 90 K or resolved crystals are compressed at room temperature, but are not found to 30 kbar for dilute solutions of 1,1′-binaphthyl in polyacrylonitrile. The planes of adjacent naphthyl residues along \overrightarrowb in the crystal are parallel but offset, the normal distance between planes being 3.55 Å; Raman spectra provide no evidence for a structural phase transformation upon compression. These new bands are assigned as the binaphthyl excimer.
  • Tetsuo Takahashi, Mamoru Nakanishi, Masamichi Tsuboi
    1978 Volume 51 Issue 7 Pages 1988-1990
    Published: 1978
    Released: April 19, 2006
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    When an 1H2O solution of N-methylacetamide was rapidly mixed with 2H2O, a time-dependent decrease of the ultraviolet absorbance at 227 nm was observed. This was not the case with N,N-dimethylacetamide. Hence, the time-dependent decrease in absorbance was attributed to be caused by the deuteration (NH→ND) reaction of N-methylacetamide. This provides an appropriate method for determining deuteration rate of the peptide group in a polypeptide or in a protein. By this method the deuteration rate of poly-D,L-alanine has been examined in the pH=5—8 and temperature=10—40 °C range. In this range, the deuteration was found to proceed always as a single first-order reaction, and the rate constant ke is expressed within an experimental error as ke=6.4×10(6+pH−3850⁄T) This is to be used as a standard rate-constant value in estimating the attenuation factor γj=kjke of a given peptide group (j) in a protein molecule whose rate constant value is kj.
  • Masao Sekizaki
    1978 Volume 51 Issue 7 Pages 1991-1995
    Published: 1978
    Released: April 19, 2006
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    The crystal structure of L-asparaginato-D-aspartatocobalt(III) monohydrate, [Co(H2NCOCH2CHNH2COO)(OCOCH2CHNH2COO)]·H2O, has been determined by an X-ray diffraction method and refined by a block-diagonal least-squares method to give R=0.033 for 1517 non-zero reflections. The crystals are orthorhombic with the space group P212121, a=11.790(2), b=17.059(2), c=5.830(2) Å, and Z=4. The complex molecule has a slightly distorted octahedral coordination with fac(N) geometry. The amide group of L-asparaginate ion is coordinated through the nitrogen atom, and an enolic system of Co←NH=C(OH)–CH2– is formed. The complex molecules are held together through hydrogen bonds which form two-dimensional networks parallel to the (010) plane. The networks are piled up through hydrogen bonds by water molecules to complete three-dimensional networks.
  • Shunichi Nishikida, Shigero Ikeda
    1978 Volume 51 Issue 7 Pages 1996-2001
    Published: 1978
    Released: April 19, 2006
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    The sulfur 1s and 2p photoelectron spectra and KL23L23 Auger electron spectra in various sulfur compounds involving solid sulfur were measured by means of irradiation by Al Kα and Cr Kα X-rays. The chemical shifts of the S1s and S2p photoelectron spectra for compounds referred to the data for solid sulfur differ from each other in magnitude, but all are larger than that for the Auger electron spectra in the corresponding compound. The shift of the Auger electron spectra is different in fashion from those of the photoelectron spectra; the difference is largely attributable to the differences in relaxation energies. The extra-atomic relaxation energies due to core-electron emission were estimated by combining the atomic spectral data and the XPS and AES data of compounds; they were found not necessarily to depend upon the atomic charges. From the calculated sulfur Kα X-ray spectra corresponding to the difference in the binding energy between 1s and 2p, the number of electrons on each sulfur atom was obtained by using the method derived from Coulson et al., while the isolation was attempted on the basis of the contribution of polarization energies due to surrounding atoms to the extra-atomic relaxation energies.
  • Yasuki Yoshimura, Nobuo Suzuki
    1978 Volume 51 Issue 7 Pages 2002-2007
    Published: 1978
    Released: April 19, 2006
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    The temperature dependence of the solubilities of 1-phenyl-1,3-butanedione (benzoylacetone) and 4,4,4-tri-fluoro-1-phenyl-1,3-butanedione (benzoyltrifluoroacetone) in water and in 1.0 mol l−1 aqueous solutions of HClO4, HCl, NaClO4, KCl, NaBr, NaCl, BaCl2, and Na2SO4 was determined over the temperature ranges of 20 to 45°C for benzoylacetone and of 15 to 30°C for benzoyltrifluoroacetone. From these data, the thermodynamic quantities associated with the dissolution in water and with the transfer from water to the aqueous electrolyt solutions were estimated. Both the enthalpy and the entropy of solution of benzoyltrifluoroacetone in water were much smaller than those for benzoylacetone. This was interpreted by assuming a higher hydrophobic hydration for the less polar benzoyltrifluoroacetone. The thermodynamic quantities of the transfer of benzoyltrifluoroacetone from water to the aqueous perchloric acid solution showed characteristic features compared with those of the other electrolyte solutions. The overall salt effect on the dissolution of benzoylacetone and benzoyltrifluoroacetone is discussed in terms of the change in the thermodynamic quantities.
  • Yoshio Kosugi, Tsugio Takeuchi
    1978 Volume 51 Issue 7 Pages 2008-2011
    Published: 1978
    Released: April 19, 2006
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    Carbon-13 NMR spectra of benzoic, and phthalic acids were compared both in D2O with an excess of sodium hydroxide and in a mixture of DMSO-d6 and H2O (4:1). Tight ion pair forms of benzoate anion were considered. A simple additive rule for isomeric phthalic acids was employed to assign the spectral peaks. These carboxylic acids gave characteristic peaks and so can be distinguished from others in mixtures. Quantitative analyses of these carboxylic acids with calibration curves are also possible by a simple preparation of basic D2O solutions. An example of the use of these data is the Henkel process (cf. Fig. 1) for the synthesis of terephthalic acid.
  • Katsuma Hiraki, Yoshio Fuchita, Yasushi Morita
    1978 Volume 51 Issue 7 Pages 2012-2014
    Published: 1978
    Released: April 19, 2006
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    Phenylethynyl[1,1,1-tris(diphenylphosphinomethyl)ethane]copper(I), [Cu(C≡CPh)(tdpme)]tdpme=1,1,1-tris(diphenylphosphinomethyl)ethane, has been prepared in good yield by a reaction between phenylethynyl-copper(I), [{Cu(C≡CPh)}n], and tdpme. From physicochemical and spectroscopic studies the complex is considered to have a monomeric tetrahedral structure. It reacts with p-cresol to give [Cu(O–C6H4–CH3-P)(tdpme)] and also with highly active hydrogen compounds, methyl cyanoacetate and methyl nitroacetate, to give [Cu{CH(CN)CO2CH3}(tdpme)] and [Cu{CH(NO2)CO2CH3}(tdpme)], respectively. However, moderately active hydrogen compounds, such as acetonitrile, dimethyl malonate, and nitromethane, do not react with [Cu(C≡CPh)(tdpme)]. The reactivities of the complex with active hydrogen compounds are discussed in correlation with the pKa values of the latter compounds.
  • Akira Nagasawa, Kazuo Saito
    1978 Volume 51 Issue 7 Pages 2015-2019
    Published: 1978
    Released: April 19, 2006
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    The ligand isotopic exchange between tris(acetylacetonato)germanium(IV) perchlorate and acetylacetone[14C] has been studied in 1,1,2,2-tetrachloroethane (TCE), nitromethane (NM), and acetonitrile (AN), at 100–120°C. In these solvents, the rate formula was R=k[H2O][complex]; the concentrations of the complex, free ligand, and water in solution were in the ranges from 0.01 to 0.1 mol dm−3. The activation enthalpies and entropies for the k’s are 105, 98, and 90 kJ mol−1; and −25, −53, and −69 J K−1 mol−1, in TCE, NM, and AN, respectively. Influence of acid and base concentrations, and deuterium isotope effect on the rate in AN suggest that the rate controlling step of the exchange is governed by the ease of the proton transfer between the leaving and the incoming acac in an intermediate.
  • Taketoshi Nakahara, Toshiaki Tanaka, Sôichirô Musha
    1978 Volume 51 Issue 7 Pages 2020-2024
    Published: 1978
    Released: April 19, 2006
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    An atomic fluorescence spectrometer with dispersive and nondispersive systems has been designed and constructed. A flameless atomic fluorescence spectrometric method with the newly constructed spectrometer is described for the determination of mercury at the nanogram level. Mercury is reduced by tin(II) chloride and released from solution by a stream of argon into a quartz fluorescence cell. The fluorescence signal is measured by dispersive and nondispersive systems. Linear analytical working curves covering the mass range of mercury from the detection limits to approximately 10 and 1 μg have been established with dispersive and nondispersive systems, respectively. With the nondispersive system a detection limit of 0.003 ppb or 0.05 ng of mercury could readily be obtained. The present method was satisfactorily applied to the determination of mercury in wastewater samples.
  • Hiroshi Taguchi, Kiyoshi Isobe, Yukio Nakamura, Shinichi Kawaguchi
    1978 Volume 51 Issue 7 Pages 2025-2029
    Published: 1978
    Released: April 19, 2006
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    Bis(acetylacetonato)oxovanadium(IV) reacts with phenol or its para-substituted derivatives in methanol, affording stable adducts with the composition of VO(acac)2(p-XC6H4OH), where X=H, NO2, CHO, COOH, Cl, or CH3. The magnetic and spectral data reveal that these are vanadium(IV) complexes containing the phenol as a neutral ligand. They show an unusually low ν(V=O) frequency of ≈900 cm−1 as compared with the value of 1000 cm−1 for the parent complex, and are presumed to have a polymeric structure with an infinite chain of V=O…V=O…. The phenol is connected by a hydrogen bond to one oxygen atom of an acetylacetonate ligand. The behavior of the complex in solution is also discussed. The addition of 1,10-phenanthroline or 2,2′-bipyridine to a reaction mixture of VO(acac)2 and nitrophenols results in phenolato complexes VO(OC6H5−nXn)(acac)(phen or bpy), where X=NO2 and n=1, 2, or 3. Two isomers of VO(OC6H2(NO2)3)(acac)(bpy) are isolated and characterized.
  • Hiroshi Taguchi, Kiyoshi Isobe, Yukio Nakamura, Shinichi Kawaguchi
    1978 Volume 51 Issue 7 Pages 2030-2035
    Published: 1978
    Released: April 19, 2006
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    Diamagnetic dioxovanadium(V) complexes, VO2(β-dik)(phen or bpy), were prepared by the direct reactions of VO(β-dik)2 with 1,10-phenanthroline and 2,2′-bipyridine in dichloromethane under aerobic conditions as well as by two other methods. These compounds were concluded to have a cis configuration on the basis of the IR and Raman data. These complexes are solvolyzed to afford the di-μ-methoxo-or di-μ-hydroxo-divanadium(V) species, and are reduced by hydrogen bromide to the oxovanadium(IV) species in dichloromethane. In methanol instead of dichloromethane, VO(acac)2 reacted with 2,2′-bipyridine to produce a novel mixed-valence divanadium(IV, V) complex, V2O3(acac)3(bpy), which was revealed by the magnetic, spectral, and polarographic data to be a trans adduct of VO(acac)2 with VO2(acac)(bpy) via an oxide ligand.
  • Koichi Kubokura, Hisashi Okawa, Sigeo Kida
    1978 Volume 51 Issue 7 Pages 2036-2040
    Published: 1978
    Released: April 19, 2006
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    Cobalt(II) complexes with Jäger-type open-chain ligands, H2(J-R) (R=en, pn, ph, and tn), were prepared. It was found that Co(J-en), Co(J-pn), and Co(J-ph) are in low-spin state, and Co(J-tn) in high-spin state with a pseudo-tetrahedral configuration. The formation constant of pyridine adduct of Co(J-en)was spectrophotometrically determined to be 2.70, 2.18, and 1.90 M−1 at 0, 20, and 30 °C, respectively. Co(J-en)py forms oxygen adducts, Co(J-en)pyO2 and [Co(J-en)py]2O2, in a 1,2-dichloroethane solution at room temperature, exhibiting a characteristic band at 525 nm. The ease of oxygenation and the characteristic absorption in the visible region were interpreted in terms of the electron-withdrawing ability of acetyl group in the ligand.
  • Hiroshi Hayakawa, Hiroaki Nakayama, Akiko Kobayashi, Yukiyoshi Sasaki
    1978 Volume 51 Issue 7 Pages 2041-2045
    Published: 1978
    Released: April 19, 2006
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    The crystal structure of the title compound has been determined by single crystal X-ray diffraction techniques. The compound crystallizes in the space group C2/c with unit-cell dimensions a=23.54(1), b=9.672(3), c=15.941(7) Å, β=114.90(4)°, and Z=4. The manganese atom is octahedrally coordinated by two triphenylphosphines in the trans positions, three equatorial carbonyl ligands, and a hydrido hydrogen. The Mn–H bond has a normal covalent length, 1.46(8) Å. The molecule has C2 symmetry, and Mn, O(1), C(1), and Hh are on special positions of (0, y, 1/4).
  • Taketoshi Nakahara, Toshiaki Tanaka, Sôichirô Musha
    1978 Volume 51 Issue 7 Pages 2046-2051
    Published: 1978
    Released: April 19, 2006
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    Atomic fluorescence spectrometry with nondispersive and dispersive systems by utilizing the arsine-generation technique is described for the determination of arsenic at the nanogram level, where the premixed argon(entrained air)- and nitrogen (entrained air)-hydrogen flames and a microwave-excited electrodeless discharge lamp were used. For the low-temperature flames, a newly designed burner has been constructed. The best detection limits obtained for arsenic are 2.3 ng in mass and 0.12 ppb in concentration with a nondispersive system in argon(entrained air)-hydrogen flame. Linear analytical working curves covering the mass range of arsenic from 30 ng to around 1000 ng have been obtained with nondispersive and dispersive systems at 193.7 and 197.2 nm in both the hydrogen flames. Several elements including other hydride-forming elements, such as antimony, bismuth, selenium, and tellurium, have caused a decrease in fluorescence signals. The present method, with the most sensitive nondispersive system and argon (entrained air)-hydrogen flame, can be applied to the determination of trace amounts of arsenic in wastewaters.
  • Kazuhiro Maruyama, Tatsuaki Iwai, Yoshinori Naruta, Tetsuo Otsuki, Yo ...
    1978 Volume 51 Issue 7 Pages 2052-2058
    Published: 1978
    Released: April 19, 2006
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    The phtoaddition reaction of 9,10-phenanthrenequinone (1) with several alicyclic olefins (6) has been investigated. In addition to the expected products, dihydrodioxin(2) and keto oxetane (3), the hydroxydihydrofuran derivative (4, 5) were found. Product distribution was shown to be deeply dependent on the structure of the olefins. Product 4 has been shown to be produced via the photorearrangement of 3.
  • Hiroshi Ishikawa, Teruaki Mukaiyama
    1978 Volume 51 Issue 7 Pages 2059-2063
    Published: 1978
    Released: April 19, 2006
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    The reduction of dialkyl acetals derived from aromatic aldehydes and ketones with TiCl4–LiAlH4 in THF or diethyl ether at room temperature afforded the coupling products, pinacol ethers or olefins, in high yields. On the other hand, when acetals derived from aliphatic aldehydes and ketones were treated with TiCl4–LiAlH4 in diethyl ether, the reductive dealkoxylation took place and the corresponding ethers were isolated in good yields. As to the reaction mechanism we propose that Ti(II) is the reactive species in reductive coupling reaction of acetals derived from aromatic aldehydes and ketones, and that Ti(0)–H2AlCl complex may be the reactive species in reductive dealkoxylation of acetals derived frcm aliphatic aldehydes and ketones.
  • Juji Yoshimura, Masafumi Matsuzawa, Masuo Funabashi
    1978 Volume 51 Issue 7 Pages 2064-2067
    Published: 1978
    Released: April 19, 2006
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    2,3,6-Trideoxy-3-C, 4-O-dimethyl-3-nitro-D-arabino-hexopyranose was synthesized by the oxidation of methyl α-glycoside of the corresponding 3-amino derivative with m-chloroperbenzoic acid followed by hydrolysis. The 3-amino derivative was synthesized from methyl 4,6-O-benzylidene-2-deoxy-α-D-erythro-hexopyranosid-3-ulose by introduction of the amino-branching function according to the method of Bourgeois, followed by 6-deoxygenation and 4-O-methylation.
  • Takaaki Horaguchi, Teishiro Abe
    1978 Volume 51 Issue 7 Pages 2068-2071
    Published: 1978
    Released: April 19, 2006
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    4,5-Dihydro-3H-naphtho[1,8-bc]furans (1a–d) reacted with a variety of electrophilic reagents to give the corresponding 2-substituted 4,5-dihydro-3H-naphtho[1,8-bc]furans. Hydrogenation of 1a–d gave the corresponding 2a,3,4,5-tetrahydro-2H-naphtho[1,8-bc]furans. 2H-Naphtho[1,8-bc]furans (7a–c) which were prepared from 1a–c were gradually converted to the 8-hydroxynaphthalene-1-carbaldehydes in air. The facile cleavage of the ether bond of 7a–c is thought due to ring strain in the 2H-naphtho[1,8-bc]furan ring system.
  • Masahiro Kondo, Isao Ando
    1978 Volume 51 Issue 7 Pages 2072-2076
    Published: 1978
    Released: April 19, 2006
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    Using the wavefunction obtained from the improved virtual orbital (IVO) method proposed by Huzinaga, the 13C NMR chemical shifts in some organic compounds (acetylene, ethylene, ethane, pentane, benzene, pyridine and acetone) have been calculated and compared with those obtained from the ordinary SCF-MO method. If the molecule considered is small, highly symmetric and non-polar, it can be expected that there is little difference in the calculated values between these two methods. If the molecule considered is rather large or polar, modification of the calculated values are apt to be induced by the IVO method. As far as qualitative tendencies of the chemical shifts of carbon in a molecule are concerned, both methods give similar results.
  • Akihiko Ishida, Teruaki Mukaiyama
    1978 Volume 51 Issue 7 Pages 2077-2081
    Published: 1978
    Released: April 19, 2006
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    1-Sorboyl-2-pyrrolidone was prepared from sorbic acid and 2-ethoxy-1-pyrroline using 1-methyl-2-chloropyridinium iodide as a coupling reagent. Variotin and its analogs were similarly synthesized from lactim ethers and (2E,4E,6E)-8-hydroxy-2,4,6-dodecatrienoic acids without protecting the hydroxyl group at C-8. (2E,4E,6E)-8-Hydroxy-6-methyl-2,4,6-dodecatrienal, a precursor of trienoic acid, was synthesized by the elimination of methanol from (2E,6E)-8-acetoxy-5-methoxy-6-methyl-2,6-dodecadienal prepared from the reaction of 1-trimethylsiloxy-1,3-butadiene with (2E)-4-acetoxy-2-methyl-2-octenal dimethyl acetal.
  • Akiko Takematsu, Kyoko Sugita, Ryohei Nakane
    1978 Volume 51 Issue 7 Pages 2082-2085
    Published: 1978
    Released: April 19, 2006
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    The competitive benzylation of benzene and toluene catalyzed by boron trifluoride hydrate was carried out with benzyl, chlorobenzyl, alkylbenzyl, and alkoxybenzyl chlorides in boron trifluoride hydrate and hexane solutions. The relative rates of toluene to benzene were smaller than 1 in the benzylation with benzyl and chlorobenzyl chlorides, while they were larger than 1 with alkylbenzyl and alkoxybenzyl chlorides. Competitive benzylation catalyzed by boron trifluoride was also carried out in a nitromethane solution. The relative rates were reduced by from several to ten times in the former solutions as compared to the latter solution; the kT/kB value became smaller than 1 when the electrophile was such a very strongly electron-deficient reagent as the benzyl or chlorobenzyl cation. On the other hand, the kT/kB value was still larger than 1 when the electrophilicity was lower, as in the alkylbenzyl or alkoxybenzyl cation. The isomer distribution was insensitive to the nature of the solvents. The formation of the meta isomer was always only a small percentage. These results substantiate our previous conclusions obtained in the ethylation and isopropylation catalyzed by boron trifluoride hydrate.
  • Hajime Irikawa, Yasuaki Okumura
    1978 Volume 51 Issue 7 Pages 2086-2090
    Published: 1978
    Released: April 19, 2006
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    The 13C NMR spectra are reported for hexahydro- and octahydro-1,4-naphthoquinones and their derivatives. The shielding trends of the methyl group are utilized for conformational analysis. A comparison of octahydro- 1,4-naphthoquinones with the corresponding decalins reveals that the effects of the carbonyl group are the large downfield shift of the α-carbons and the upfield shifts of the β- and γ-carbons.
  • Takakazu Yamamoto, Yasuhiro Hayashi, Akio Yamamoto
    1978 Volume 51 Issue 7 Pages 2091-2097
    Published: 1978
    Released: April 19, 2006
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    Transition metal compounds including NiCl2(bpy) (bpy=2,2′-bipyridine), NiBr2(PPh3)2 (PPh3=triphenylphosphine), PdCl2(bpy), NiCl2, CoCl2, FeCl2, and FeCl3 catalyze polycondensation of di- and polyhalogenated organic aromatic compounds by dehalogenation with magnesium under mild conditions. Poly(p-phenylene), poly(m-phenylene), poly(oxybiphenylene), and poly(phenylenemethylene) were prepared from p-dihalobenzene, m-dichlorobenzene, bis(p-bromophenyl) ether, and α,p-dichlorotoluene. They have a high degree of polymerization and high thermal stability. Poly(p-phenylene), poly(oxybiphenylene), and poly(phenylenemethylene) have regularly repeated structures as proved by IR spectroscopy and X-ray powder diffraction. Polymerization of polyhalogenated aromatic compounds (1,3,5-trichlorobenzene and hexachlorobiphenyl) in tetrahydrofuran (THF) gave copolymers having aromatic nuclei and THF units. Polymerization of the haloaromatic compounds is considered to proceed through a mechanism in which consecutive cycles of oxidative addition of haloaromatic compounds (R–X) to the transition metal catalyst take place so as to cause alkylation (arylation) by the Grignard reagent formed in the system (R′MgX) and elimination of R–R′ from an active transition metal compound having R and R′ groups.
  • Masashi Inoue, Yoshio Taguchi, Toshio Sugita, Katsuhiko Ichikawa
    1978 Volume 51 Issue 7 Pages 2098-2107
    Published: 1978
    Released: April 19, 2006
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    The acid catalyzed ethanolysis of trans-2,3-diphenyloxirane was examined in a wide variety of binary ethanolic solvent systems. The reaction proceeded with 26% retention and 74% inversion of configuration in pure ethanol at 50 °C. The dilution of ethanol by hexane or benzene produced almost no change in stereochemistry of the ethanolysis. The addition of acetonitrile, nitromethane, or sulfolane to the ethanolic solution resulted in increased degrees of retention. In binary ethanolic mixtures containing DMSO, DMF, or HMPA, increased ratios of inverted product were obtained. The steric course of the ethanolysis could be controlled from 85% retention–15% inversion (CH3NO2:ethanol=20:2 by volume) to 10% retention–90% inversion (HMPA: ethanol=10:12) by the choice of co-solvent. The results are discussed in terms of the solvation-shell concept.
  • Kenji Uneyama, Manabu Kuyama, Sigeru Torii
    1978 Volume 51 Issue 7 Pages 2108-2111
    Published: 1978
    Released: April 19, 2006
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    The acid-catalyzed cyclization of 2-phenylsulfonyl-4,8-dimethyi-3,7-nonadienoic acid (5) was performed by treatment with sulfuric acid-acetic acid and/or boron trifluoride in various aprotic solvents to afford 2,2,6-trimethyl-9-phenylsulfonyl-7-oxabicyclo[4.3.0]nonan-8-one (4) in 70–75% yield. Similarly, 2-phenylsulfonyl-2-(2,6,6-trimethyl-1,3-cyclohexadienyl)acetic acid provided 2,2,6-trimethyl-9-phenylsulfonyl-7-oxabicyclo[4.3.0]non-4-en-8-one (7) in 62% yield. The lactones 4a, 4b, and 7 were converted into dihydroactinidiolide, tetrahydroactinidiolide, and 4,5-dihydroactinidiolide. The reaction conditions and mechanism of the cyclization of 5 are discussed.
  • J\={u}ro Ojima, Y\={u}ji Shiroishi, Masamitsu Fujiyoshi
    1978 Volume 51 Issue 7 Pages 2112-2115
    Published: 1978
    Released: April 19, 2006
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    The conjugate aldehydes, containing terminal acetylenes, were converted to the corresponding conjugated azines 6ac and 8ac, respectively. Oxidative couplings of these azines were attempted. The azines 6b, 6c, and 8b afforded the corresponding cyclic dimers 9, 10, and 11, respectively. Examination of 1H NMR spectra indicates that the tetraazaannulenes are atropic.
  • Ken-ichi Sato, Juji Yoshimura
    1978 Volume 51 Issue 7 Pages 2116-2121
    Published: 1978
    Released: April 19, 2006
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    The stereoselectivities in the diazomethane reaction of methyl 4,6-O-benzylidene-2-O-methyl-α-D-ribo-hexopyranosid-3-ulose (2), its 2-epimer (3), β-anomer of 2 and the corresponding 2-O-Benzoyl derivative were examined, in comparison with those in the Grignard reaction and sodium borohydride reduction. The complemental stereoselectivity of diazomethane reaction in the case of 2 and 3 indicated that the electrostatic attractive effect in the transition state between diazomethyl cation and the axial methoxyl oxygen at the α-position to carbonyl function in 3 is much stronger than that at β-position which is predominat in the case of 2. In cases of β-anomers having no axial oxygen, stereoselectivies were preferentially controlled by the usual steric factors.
  • Shoichi Kusumoto, Satoshi Okada, Koji Yamamoto, Tetsuo Shiba
    1978 Volume 51 Issue 7 Pages 2122-2126
    Published: 1978
    Released: April 19, 2006
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    Seven acyl derivatives of N-acetylmuramyl-L-alanyl-D-isoglutamine, which had previously been shown to be a minimum structure required for the immunoadjuvant activity, were synthesized in order to evaluate the significance of lipophilicity on the adjuvant activity and on the possible antitumor effect. Among them, are included 6-O-docosanoyl, stearoyl, lauroyl, octanoyl, butyryl, acetyl, and 4,6-di-O-acetyl derivatives. Some of these compounds were found to serve an improvement in the administration method to living body.
  • Kazuhiko Nonaka, Kazuki Sato, Shigeyuki Terada, Tetsuo Kato, Nobuo Izu ...
    1978 Volume 51 Issue 7 Pages 2127-2130
    Published: 1978
    Released: April 19, 2006
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    Two analogs of gramicidin S, [2-L-histidine]-gramicidin S (14) and [2,2′-di-L-histidine]-gramicidin S (19), were synthesized to compare the biological role of δ-amino groups in L-ornithine residues in the antibiotic with that of weakly basic imidazolyl groups in L-histidine residues. Compound 14 exhibited identical activity to that of gramicidin S, but 19 was only 1/8 as active. The optical rotatory dispersions of these analogs and gramicidin S were nearly the same: molecular conformation of these peptides must be very similar. Compounds 14 and 19 showed esterolytic activity against p-nitrophenyl acetate. The activity of 14 was higher than that of imidazole, 14 being more active than 19.
  • Toyonobu Asao, Morio Yagihara, Yoshio Kitahara
    1978 Volume 51 Issue 7 Pages 2131-2135
    Published: 1978
    Released: April 19, 2006
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    The sensitized photooxidation of cycloheptatriene (tropilidene) in methanol afforded (4π+2π) cycloadduct; 8,9-dioxabicyclo[3.2.2]-2,6-nonadiene (1), 6-hydroxy-2,4-cycloheptadienone and 6-oxoheptadienal presumably derived from (6π+2π) cycloadduct, and small amounts of tropone and benzaldehyde. Mechanism of their formation are discussed. It was found that the treatment of the photooxidation mixture with trie thy lamine afforded tropone in about 50% yield. Thermal isomerization of 1 in refluxing xylene afforded cis-3,9-dioxatricyclo-[6.1.0.02.4]-5-nonene, 8-oxabicyclo[5.1.0]-4-octen-3-one and 4-hydroxy-2,6-cycloheptadienone.
  • Shin Suzuki, Rebati C. Das, Kieko Harada
    1978 Volume 51 Issue 7 Pages 2136-2141
    Published: 1978
    Released: April 19, 2006
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    1-(p-Dimethylaminophenylazo)-2-naphthol-3,6-disulfonic acid is formed in many important commercial “dry process” diazo-printing. Some physico-chemical properties of this dye in solutions have been investigated. Its absorption spectra in various solvents and in water at various acidities have been discussed on the basis of azoquinone hydrazone tautomeric and acid-base equilibria respectively. The dissociation constants of the acid-base equilibria in the pH range of 1–14 in aqueous solutions have been determined at 25 °C and 1.0 M ionic strength. Conductivities of aqueous solutions at various concentrations and temperatures have been interpreted on the basis of the colloidal nature of the dye. The polarograms of the compound have been drawn at various pH’s and discussed. Polarographic method indicates complex formation between Zn(II) salt and the dye in the mole ratio of 1:2.
  • J. R. Merchant, S. Y. Dike
    1978 Volume 51 Issue 7 Pages 2142-2144
    Published: 1978
    Released: April 19, 2006
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    A general and convenient synthesis is described of a number of 2,3-dihydro-4H,5H-pyrano[3,2-c][1]benzopyran-4,5-diones and 2,3-dihydro-4H,5H-pyrano[2,3-b][1]benzothiopyran-4,5-diones. It involves the condensation of 4-hydroxycoumarin derivatives and their thioanalogs with different α,β-unsaturated acids in the presence of PPA. Assignments of the structures in both the cases are based on analytical and spectroscopic evidence.
  • S. Y. Dike, J. R. Merchant
    1978 Volume 51 Issue 7 Pages 2145-2147
    Published: 1978
    Released: April 19, 2006
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    The reaction of 4-hydroxycoumarin and 4-hydroxythiocoumarin with citral in basic as well as acidic conditions led to the formation of tetrahydrocannabiol derivatives. With citronellal, the above hydroxycoumarins afforded the corresponding hexahydrocannabiol derivatives in moderate yields. The structures and the stereochemistry of the compounds obtained are established on the basis of spectral-analytical evidence.
  • A. F. M. Fahmy, N. F. Aly, M. O. Orabi
    1978 Volume 51 Issue 7 Pages 2148-2152
    Published: 1978
    Released: April 19, 2006
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    N-Hydroxyphthalimide undergoes ammonolysis to give phthalimide. N-(Aroyloxy)phthalimides undergo alcoholysis followed by ammonolysis to give mixtures of phthalimide and ester. N-(Arylsulfonyloxy)phthalimides undergo ammonolysis, followed by Lossen rearrangement to give mixtures of 2,4-quinazolinedione and ammonium salts of arenesulfonic acids. N-Hydroxyphthalimide undergoes aminolysis to give the corresponding N-arylphthalimides. N-Hydroxyphthalimide reacts with hydrazine hydrate and/or phenylhydrazine in acetic acid or ethanol to give the corresponding 1,4-phthalazinedione, or by fusion to give phthalimide and N-phenylphthalimide, respectively. Pyrolysis of N-hydroxyphthalimide gives phthalimide, and N-(aroyloxy)phthalimides give mixtures of phthalimide and carboxylic acids. N-(Arylsulfonyloxy)phthalimides give mixture of phthalimide and arenesulfonic acids. However, pyrolysis of N-(arylcarbamoyloxy)phthalimides gave N-arylphthalimides. N-Hydroxyphthalimide reacts with phenylmagnesium bromide to give 1,1-diphenyl-3-(phenylimino)-1,3-dihydroisobenzofuran via ring opening followed Beckmann rearrangement, while N-(arylsulfonyloxy)phthalimides react with arylmagnesium bromide to give mixtures of [O-(arylamino)phenyl]diarylmethanols, and arenesulfonic acids via ring opening followed by Lossen rearrangement.
  • Kalyan K. Banerji, Sudheer K. Banerjee, Rama Shanker
    1978 Volume 51 Issue 7 Pages 2153-2155
    Published: 1978
    Released: April 19, 2006
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    The oxidation of eight esters of mandelic acid by lead tetraacetate in benzene solution has been studied. The product of the oxidation is the corresponding phenylglyoxylic ester. The oxidation is of first order with respect to the oxidant and second order to the ester. The reaction is catalysed by pyridine, the catalysed reaction being first order in pyridine. In the presence of pyridine, the reaction is first order with respect to each the oxidant and the ester. The oxidation of ethyl α-deuteriomandelate indicated a kinetic isotope effect. The activation parameters have been determined. The results have been interpreted in terms of a slow decomposition of lead tetraalkoxide derivative involving heterolysis of Pb–O bond.
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