Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
Volume 61 , Issue 3
Showing 1-50 articles out of 73 articles from the selected issue
  • Minoru Sakiyama, Nobuhiro Kuriyama, Akira Imamura, Shigeo Murata
    1988 Volume 61 Issue 3 Pages 615-620
    Published: 1988
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Hückel MO calculations were made for the title compounds using Hess–Schaad heteroatom parameters. The bond-contribution values were determined for the total π-bonding energies of the acyclic compounds. No resonance stabilization is present for molecules with six-, eight-, and ten-membered rings composed of CO–N linkages. Graph-theoretical calculations gave a similar result. Atomization enthalpies were calculated from the available thermochemical data and analyzed within the framework of the Hess–Schaad theory. The destabilization energies of normal alkanamides and N,N-dimethylformamide are close to zero. Diacetamide is not destabilized, while N-butyldiacetamide and triacetamide showed small destabilization energies. Trimethyl isocyanurate is not significantly strained. The total strengths of the CO–N bonds are in this order: amide>(urea and diacetamide)>internal bond of acetylurea.
  • Taihei Nitadori, Tatsumi Ichiki, Makoto Misono
    1988 Volume 61 Issue 3 Pages 621-626
    Published: 1988
    Released: June 27, 2006
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    The catalytic activities of perovskite-type mixed oxides (LnBO3 and Ln0.8Sr0.2CoO3, Ln=rare-earth (lanthanoid) elements, B=3d transition metals) for the oxidation of propane and methanol have been studied comparatively. It has been found that the catalytic activities of LnBO3 were principally determined by the B-site elements and were similar to those of the corresponding oxides of the B-site elements. The roles of the rare-earth ions of the A-site were secondary as long as they were trivalent. Upon the partial replacement of Ln3+ by Sr2+, the catalytic activities of LnCoO3 increased several times, the magnitude of the increase being similar among all the rare-earth ions. These results demonstrate that the kind and the valence of a B-site metal are of primary importance for the control of the catalytic activity for oxidation, almost regardless of the kind of trivalent rare-earth elements at the A-site.
  • Yasuyuki Takeda, Koji Katsuta, Yoshihisa Inoue, Tadao Hakushi
    1988 Volume 61 Issue 3 Pages 627-632
    Published: 1988
    Released: June 27, 2006
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    Conductivities of alkali metal salts in the presence of 15-crown-5 (15C5), 16-crown-5 (16C5), and benzo-15-crown-5 (B15C5) were measured at 25 °C in acetonitrile, propylene carbonate, and methanol. Formation constants (KML+) of 1:1 complexes of 15C5 and 16C5 with alkali metal ions and conductance parameters (λ0 and å) of the Na+ complexes of 15C5, 16C5, and B15C5 were determined, λ0 and å being limiting ionic molar conductivity and distance of closest approach of ions, respectively. In general, selectivities of 15C5 and 16C5 for alkali metal ions show the size-fit correlation. In contrast to 15C5, 16C5 forms much the most stable complex with Na+ in every solvent. Generally, KML+-value sequences of a given crown ether complex for the solvents are the reverse of donor-number sequences of the solvents. Value of å increases with an increase in the cationic size (Na+→Na(15C5)+→Na(16C5)+→Na(B15C5)+). Mobility of the Na+–crown ether complex decreases with an increase in the size of the crown ether. From λ0 values and Walden products of these Na(crown ether)+ complexes and a tetrapropylammonium ion, it seems likely that Na(15C5)+ and Na(16C5)+ act as structure breakers in hydrogen-bonding solvents, whereas Na(B15C5)+ as a structure maker.
  • Keitaro Kiyosawa
    1988 Volume 61 Issue 3 Pages 633-642
    Published: 1988
    Released: June 27, 2006
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    The osmotic pressures of aqueous saccharide solutions were calculated from the data obtained by means of the freezing-point-depression method. Thus, the water activity and the osmotic pressure of D-glucose, sucrose, and raffinose solutions were measured by the freezing-point-depression method. For dilute aqueous saccharide solutions, the freezing-point depression was proportional to their molal concentrations. However, the higher the molal concentration, the larger the freezing-point depression observed became than those to be expected from the molal concentration dependent on the size of the saccharide molecules. The osmotic pressures calculated from the data of the freezing-point-depression method were compared with those measured with semi-permeable membranes by Morse and his colleagues. To obtain the apparent volumes of hydrated D-glucose, sucrose, and raffinose molecules, their partial molal volumes were measured, together with the partial molal volumes of the water of their solutions. The partial molal volumes of the water were verified to be equal to the molar volumes of pure water up to the highest concentrations examined. The apparent volumes of the hydrated D-glucose, sucrose, and raffinose molecules were calculated to be 0.1865, 0.3525, and 0.5105 nm3 respectively.
  • Naohisa Kure, Takayuki Sano, Shoji Harada, Tatsuya Yasunaga
    1988 Volume 61 Issue 3 Pages 643-653
    Published: 1988
    Released: June 27, 2006
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    Both static and kinetic investigations have been performed on the interaction of calf thymus DNA with Acridine Orange (AO). The binding isotherm obtained spectrophotometrically was analyzed by a site exclusion theory and revealed the presence of two binding modes of dye molecule corresponding to intercalation and dimerization on DNA. In the kinetic experiments focusing on the intercalation mode by the temperature-jump technique, three relaxations were observed. From the analyses of both the relaxation time and amplitude, the two fast relaxations were ascribed to parallel binding reactions including a bimolecular pathway for direct transfer of dye molecule on the polymer and the slow relaxation was attributable to a conformational change of DNA molecules. The binding parameters kinetically obtained suggest that 80% of bound AO is in intercalated form and the remainder is in partially intercalated one as an external bound form.
  • Yasuyuki Takeda, Toshihiro Kumazawa
    1988 Volume 61 Issue 3 Pages 655-658
    Published: 1988
    Released: June 27, 2006
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    Stability constants in acetonitrile and methanol of 1:1 benzo-15-crown-5 (B15C5)–alkali metal ion complexes and the solubility of B15C5 in acetonitrile, propylene carbonate, methanol, and water were determined at 25 °C by conductometry and spectrophotometry, respectively. In general, selectivity tendency of B15C5 for the alkali metal ions except for Li+ can be interpreted in terms of size-relationship. Stability sequences of the B15C5–alkali metal ion complex among the solvents, except for Rb+ and Cs+ complexes, are the reverse of solvation-ability sequences of the solvents to the corresponding alkali metal ion. By using the stability constants of the B15C5–alkali metal ion complexes, transfer activity coefficients (γ) of the B15C5 complexes were then calculated from γ values of B15C5 (obtained from solubilities of B15C5) and those of alkali metal ions. The γ value of the B15C5 complex from methanol to acetonitrile and propylene carbonate generally varies with a variety of alkali metal ions. From γ values of the B15C5 complexes, it is concluded that there exists a possible specific interaction between the alkali metal ion held in the B15C5 cavity and solvent molecules when the alkali metal ion is much smaller or larger than the B15C5 cavity.
  • Hiroshi Ichikawa, Yukiko Ebisawa, Keiichiro Sameshima
    1988 Volume 61 Issue 3 Pages 659-666
    Published: 1988
    Released: June 27, 2006
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    The analysis of the potential and kinetic energy changes between conjugative and nonconjugative structure in vinylamine and nitroethene led to the conclusion that there were two different types of conjugations: the conjugative stability caused by a decrease in the kinetic energy and that given by a decrease in the potential energy. Those two types could be termed conjugations of kinetic energy origin and potential energy origin respectively. The cojugative stability in vinylamine is produced by an excess decrease in the kinetic energy over the increase in the potential energy (kinetic energy origin), which was attributed to a release of the kinetic energy pressure of the lone pair of electrons on nitrogen. On the other hand, the conjugation of nitroethene causes an overwhelming decrease in the potential energy, especially in that belonging to the nitro group (potential energy origin).
  • Ken-ichi Maruya, Tatsuichi Maehashi, Takashi Haraoka, Shinichiro Narui ...
    1988 Volume 61 Issue 3 Pages 667-671
    Published: 1988
    Released: June 27, 2006
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    The CO–H2 reaction over ZrO2 was studied in detail. Methanol and isobutene were selectively formed at 473–523 and 623–673 K, respectively. The activation energies for C2, C3, and linear C4 hydrocarbon formation are 79, 84, and 96 kJ mol−1 (523–723 K), while that for branched-chain C4 hydrocarbons is about 210 kJ mol−1 (523–623 K). At 673 K the rate of C4 hydrocarbon formation is as follows: r=kPH2·Pco2, while those of C1, C2, and C3 are written by the functions having the maximum values regarding CO pressure. C4 hydrocarbons consist mostly of isobutene at the temperature. From these results it was concluded that isobutene is formed via different path from those of C1, C2, C3, and linear C4 hydrocarbons. The addition of high electronegative oxides such as SiO2 and Nb2O5 resulted in the decrease of isobutene and the increase of methane. The selective formation of isobutene proceeds over pure ZrO2 and ZrO2 modified with 3a Group and basic metal oxides. The nature of active site for isobutene formation was discussed.
  • To-oru Nakayama, Iwao Watanabe, Shigero Ikeda
    1988 Volume 61 Issue 3 Pages 673-677
    Published: 1988
    Released: June 27, 2006
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    The external ionization potentials for alkylbenzenes in acetonitrile and nitrobenzene have been measured by photoelectron emission spectroscopy to determine electronic polarization energies and reorganization energies. The polarization energy is used to discuss the solvation structure of alkylbenzene. The solvation behavior of alkylbenzene is found to be different from that of butylamine, previously reported. We have obtained the evidence of the approach of solvent molecules to the plane of benzene ring.
  • Kazuya Saito, Tooru Atake, Hideaki Chihara
    1988 Volume 61 Issue 3 Pages 679-688
    Published: 1988
    Released: June 27, 2006
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    Heat capacities of crystalline biphenyl were measured between 3 and 300 K by adiabatic calorimetry and some thermodynamic functions including the calorimetric standard entropy were tabulated. Thermodynamic properties of the successive phase transitions were determined; for the twist transition at (40.4±0.2) K, ΔtrsH=(5.02±0.08) J·mol−1 and ΔtrsS=(0.129±0.003) J·K−1·mol−1, and for the lock-in transition at (16.8±0.1) K, ΔtrsH=(0.15±0.02) J·mol−1 and ΔtrsS=(0.009±0.001) J·K−1·mol−1. Anomalously large heat capacities at low temperatures were analyzed based on lattice dynamics calculation, and the crossover of the low temperature heat capacities of biphenyl and p-terphenyl was attributed to the greater activity of the twisting mode in biphenyl. The relation of the bond flexibility to the incommensurability is discussed through the comparison of the low temperature heat capacities of biphenyl, p-terphenyl, and 4,4′-difluorobiphenyl.
  • Emiko Ohyoshi
    1988 Volume 61 Issue 3 Pages 689-692
    Published: 1988
    Released: June 27, 2006
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    Complex formation (1:1) between lanthanoids(III) and 2-(5-bromo-2-pyridylazo)-5-(N-propyl-3-sulfopropylamino)phenol (5-Br-PAPS, HL) has been studied by spectrophotometry at 25 °C and at I=0.1 (NaNO3). The protonated complex MHL is found to exist in equilibrium with the normal complex ML at pH 5–6. The formation constants KML and KMHL are obtained by a graphical analysis. The KML values uniformly increase with increasing atomic number except for those in the Gd–Ho region where a distinct decrease is observed. However, there is little variation in the KMHL values with atomic number. A linear relation holds well between log KML values of 5-Br-PAPS and 4-(2-pyridylazo)resorcinol (PAR) complexes for the elements up to Eu(III), the intercept of which reflects the difference in the basicity of the oxygen atom ortho to the azo group between the two ligands. This is not the case for log KMHL of the two systems.
  • Yoichi Shimura
    1988 Volume 61 Issue 3 Pages 693-698
    Published: 1988
    Released: June 27, 2006
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    Quantitative scale of a new parameter d has been proposed for the spectrochemical series of ligands in the mixed ligand complexes of d6 metals, which enables us to predict the positions of low energy d–d absorption bands of a d6 complex. Introduction of a new reduction parameter α has improved the prediction of the d–d bands of mixed cyano complexes of cobalt(III), mixed halogeno complexes of rhodium(III), iridium(III), and platinum(IV), and also several mixed carbonyl complexes of low-valent d6 metals.
  • Shinji Toyota, Michinori Oki
    1988 Volume 61 Issue 3 Pages 699-705
    Published: 1988
    Released: June 27, 2006
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    The rates of dissociation of the olefin in the title compounds were determined by the dynamic NMR technique by taking advantage of the line shape change due to the isopropyl-methyl protons. The rates of dissociation were independent of concentration in bromoform-d solutions. The free energy of activation was between 17.0 and 19.1 kcal mol−1 at 353 K for the compounds, of which line shapes were fully analyzed, depending upon the substituent in the pyridine ring and electron-withdrawing substituents giving low activation energy. The solvent effect was noticed on the dissociation rates: Aromatic hydrocarbons give higher rates of dissociation than halogenated hydrocarbons. Although solvents of strong affinity toward platinum(II) tend to decompose the complex, tetrahydrofuran-d8 was found to give definitely higher rates of dissociation of the olefin in trans-dichloro(4-methoxycarbonylpyridine 1-oxide)(3-methyl-1-butene)platinum(II) than bromoform-d, when it was used as a solvent. The mechanism of dissociation was discussed from the available data.
  • Michinori Oki, Yasuhisa Yamada, Shigeru Murata
    1988 Volume 61 Issue 3 Pages 707-714
    Published: 1988
    Released: June 27, 2006
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    Kinetics of sulfur inversion in the title compound was studied by the classical method to afford the following kinetic parameters for the process (1r,3R,4S)→(1s,3R,4S): ΔH\ eweq 25.7±0.3 kcal mol−1, ΔS\ eweq −2.2±0.8 cal mol−1 K−1. X-Ray crystallography of one isomer (1r,3R,4S) in which the methyl groups are cis to the phenyl group shows some abnormal bond lengths and conformations due to the steric congestion in the 3,4-region of the thiolane ring. The anomalies in the structure are pointed out by comparing the structure with those closely related and the correlation of them with the barrier height to inversion is discussed.
  • Kazuhiko Ozutsumi, Shin-ichi Ishiguro, Hitoshi Ohtaki
    1988 Volume 61 Issue 3 Pages 715-722
    Published: 1988
    Released: June 27, 2006
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    The structure of the monochlorocopper(II), trichloro- and tetrachlorocuprate(II) complexes in N,N-dimethylformamide (DMF) has been studied by the X-ray diffraction method at 25 °C. The radial distribution curve obtained for a solution containing the monochlorocopper(II) complex as the predominant species reveals the presence of an axially elongated octahedral [CuCl(dmf)5]+ complex, three Cu–O(eq) and two Cu–O(ax) bond lengths being 199(1) and 239(4) pm, respectively. The chloride ion binds to the copper(II) ion at the equatorial site and the Cu–Cl distance is 220(2) pm. The Cu–O(eq) bond length within the [CuCl(dmf)5]+ complex is practically the same as that within the [Cu(dmf)6]2+ (203 pm). The X-ray scattering data of solutions containing the tri- and tetrachlorocuprate(II) complexes as the main species are well explained in terms of the existence of the distorted tetrahedral [CuCl3(dmf)] and [CuCl4]2− complexes, respectively, in the solutions. The Cu–Cl and Cu–O bond lengths within the [CuCl3(dmf)] complex are 219(1) and 230(13) pm, respectively. The Cu–O distance within the complex is longer than that of the equatorial Cu–O bond within the [Cu(dmf)6]2+ and [CuCl(dmf)5]+ ions. The Cu–Cl bond length within the [CuCl4]2− complex is 226(1) pm and is longer than that within the [CuCl3(dmf)]2− complex. The nonbonding Cl···Cl distances within the [CuCl4]2− complex are 346(3) and 412(6) pm.
  • Takashi Matsumoto, Sachihiko Imai, Yasuhiro Sunaoka, Takashi Yoshinari
    1988 Volume 61 Issue 3 Pages 723-727
    Published: 1988
    Released: June 27, 2006
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    A resin acid, (+)-dehydroabietic acid, was converted into 3,4,4a,9,10,10a-hexahydro-7-methoxy-10aβ-methyl-4aαH-phenanthren-1(2H)-one (2) by the introduction of oxygen functions at the C-4 and C-13 positions, and a rearrangement of the angular methyl group to the C-5 position. The hydrophenanthrene derivative 2 was further transformed into 2,3,3a,4,5,9b-hexahydro-7-methoxy-3aβ-methyl-9bαH-1H-benz[e]inden-3β-ol (3). Since the conversion of 3 into steroidal hormones has already been reported, the present synthesis can be regarded as the synthesis of steroidal hormones from (+)-dehydroabietic acid.
  • Masahiro Minabe, Masaaki Yoshida, Yutaka Takabayashi, Masatoshi Masuda
    1988 Volume 61 Issue 3 Pages 729-733
    Published: 1988
    Released: June 27, 2006
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    Acetylations of 2- and 3-methoxy-4H-cyclopenta[def]phenanthrene gave predominantly the 1- and 8-acetyl derivatives, respectively. The acetylation of the 1-methoxy compound afforded the 2-, 3-, 5-, 7-, and 8-yl ketones and the reaction of the 8-methoxy derivative yielded the 1- and 3-acetyl derivatives. Similar reactions of 1-, 2-, 3-, and 8-methoxy-4H-cyclopenta[def]phenanthren-4-one occurred mainly at the 2-, 1-, 8-, and 9-positions, respectively.
  • Norihiro Tokitoh, Renji Okazaki
    1988 Volume 61 Issue 3 Pages 735-740
    Published: 1988
    Released: June 27, 2006
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    α-Siloxy amines, which were easily prepared by “silicon Polonovski reaction” of tertiary amine N-oxides with trialkylsilyl trifluoromethanesulfonate, were treated with various nucleophiles to give the corresponding α-functionalized tertiary amines in moderate to good yields. This new method has the advantage that it enables the α-substitution of amines not only by alkyl groups but also by alkenyl and aryl groups with sp2 carbon as a reaction center, since the introduction of such groups is difficult in electrophilic substitution of dipole-stabilized α-lithio amines. Besides the organometallics such as Grignard and organoaluminum reagents, trimethylsilyl cyanide and silyl enol ether could also be employed as nucleophiles in the presence of an appropriate Lewis acid.
  • Koichi Kikuchi, Hiroyuki Kamio, Kazuya Saito, Stelios Y. Yiannopoulos, ...
    1988 Volume 61 Issue 3 Pages 741-743
    Published: 1988
    Released: June 27, 2006
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    The I3, ClO4, and PF6 salts of unsymmetrical donors containing fused pyrazino groups (DMPDSDTF and DM(DMP)DSDTF) were prepared electrochemically and their electrical conductivities were measured. The I3 salt of DM(DMP)DSDTF exhibited a metallic behavior down to about 120 K. The radical salts of unsymmetrical donors showed much larger conductivities than those of the corresponding symmetrical donors containing pyrazino groups.
  • Yusuke Yasuda, Satoshi Shinbo
    1988 Volume 61 Issue 3 Pages 745-751
    Published: 1988
    Released: June 27, 2006
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    Striking interference effects of He molecules on the motion of Xe in micropores of 5A zeolites have been found by the frequency response method. Results of the systems reveal that the absorbed Xe molecules may be divided into two abspecies, c1′ and c2′, in the presence of He molecules which were inert in a single component system: (i) at 273 K, c1′ diffuses faster and c2′ slower than pure Xe; (ii) at 255 K, c1′ diffuses faster than pure Xe, while the motion of c2′ is regarded as not diffusion but adsorption. The interference effects at 273 K have been explained quantitatively by decoupling a more general form of Fick’s law containing cross terms.
  • Tetsuo Moriya
    1988 Volume 61 Issue 3 Pages 753-759
    Published: 1988
    Released: June 27, 2006
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    The fluorescence behavior of 7-hydroxycoumarin and 7-hydroxy-4-methylcoumarin has been studied in acidic aqueous solutions by changing the concentration of chloride ions as a fluorescence quencher. The intensity decrease and lifetime change in fluorescence from neutral and tautomeric forms of photo-excited states are explained by an interaction between protonated molecules generated in excited state and chloride ions. The magnitude of quenching-rate constant is estimated under steady-state conditions and the result is compared with the analysis using time-dependent response.
  • Yoshiya Kera, Takashi Inoue, Yoshihiro Matsukaze
    1988 Volume 61 Issue 3 Pages 761-768
    Published: 1988
    Released: June 27, 2006
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    Monolayer or less monolayer vanadium oxide catalysts supported on TiO2(rutile and anatase), V2O5/R-and A-TiO2, were prepared by a “column-exchange adsorption” method such as passing an oxovanadium ion solution, the pH of which was adjusted at 2, 4, and 7, through a column packed with titania (TiO2) for impregnation. V2O5/R-TiO2 pretreated at 450 °C showed an ESR spectrum with an unresoluved hfs for V(IV) ions at 77 K without depending upon the pH upon impregnation. V2O5/A-TiO2 petreated at room temperature showed quite small ESR signals due to Ti(III) and V(IV) ions. These signals tended to be intensive with increasing pH upon impregnation. After a heat treatment at 400 °C a huge and quite broad spectrum, which was ascribed to some reduced vanadia species(V2O5−δ), appeared in addition to the spectra for the Ti(III) and V(IV) ions, while such a change was never found in V2O5/R-TiO2. Based on a theoretical treatment for the g-values, V(IV) ions on V2O5/R-TiO2 have been confirmed to be replaced just into Ti ion sites on rutile(almost D2h symmetry). With V2O5/A-TiO2, V(IV) ions were shown to be placed so as to be partially subject to an anatase surface field(almost D2d symmetry); that is, to be placed only near the vacant Ti ion site on anatase. From a comparison of the hf-coupling constant the vanadia species on rutile was clearly shown to interact more strongly with the surface than that on anatase. The 2-propanol decomposition rates over the catalysts were measured in the temperature range 270–350 °C as a test reaction. The activity of V2O5/R-TiO2 was generally higher than that of V2O5/A-TiO2. The lowest activation energy was obtained upon the impregnation at pH=2 for V2O5/R-TiO2 and at pH=7 for V2O5/A-TiO2. The best catalyst was not necessarily prepared through conditions with pH=4, which had been suggested as giving an effective monolayer-vanadia species.
  • Shunzo Yamamoto
    1988 Volume 61 Issue 3 Pages 769-774
    Published: 1988
    Released: June 27, 2006
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    The intensities of the 307.6 nm resonance line of zinc were measured as a function of the alkane pressure at various temperatures between 556 and 696 K, and the quenching rate was determined on the basis of the Stern–Volmer plots. Assuming that the quenching rate constant, kQ, of a certain alkane is equal to the sum of the quenching-rate constant, ki, for each C–H bond, the ratios of ks/kp and kt/kp (kp, ks, and kt are the quenching-rate constants for primary, secondary, and tertiary C–H bonds) were estimated from the ratios of the quenching rates of butane, isobutane, and neopentane. The differences in the activation energies for the quenching for primary, secondary, and tertiary C–H bonds were obtained from the temperature dependence of the ratios of ks/kp and kt/kp and were interpreted in terms of the modified bond-energy-bond-order (BEBO) method.
  • Makoto Nagase, Yasuhiko Yukawa, Yoshie Inomata, Toshio Takeuchi
    1988 Volume 61 Issue 3 Pages 775-781
    Published: 1988
    Released: June 27, 2006
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    Complexes of five bivalent metals with (S)-4-thiazolidinecarboxylic acid((Remark: Graphics omitted.)) have been prepared by three methods and characterized by means of infrared absorption, reflection spectra, magnetic susceptibility, thermal analysis, powder X-ray patterns, and single crystal X-ray diffraction. Two types of complexes were found. The first type[A] included ML2·nH2O (M=Co(II), Ni(II), Cu(II), Zn(II), Cd(II); L=(S)-4-thiazolidinecarboxylate anion) and ZnClL(HL) was the second type[B]. In A-type complexes, the ligand coordinates to the metal with a nitrogen atom and an oxygen atom. From the results of single-crystal X-ray diffraction studies, the second type-B ZnClL(HL) was found to be orthorhombic, with the space group P212121; a=9.719(2), b=22.194(4), c=5.8537(5) Å, U=1262.6(4) Å3, Z=4, Dm=1.91 Mg m−3, Dx=1.93 Mg m−3, and μ(Mo K α)=25.3 cm−1. Block-diagonal least-squares refinements have led to a final R value of 0.045. The zinc atom is penta-coordinated, being ligated with one carboxylate oxygen atom of (S)thiazolidinium-4-carboxylate, which has a zwitter ion structure, two carboxylato oxygen atoms and one nitrogen atom of (S)-4-thiazolidinecarboxylate anion, and a chloride atom. The structure comprises onedimensional polymers by the carboxylate oxygen atom of this anion-type ligand. The plane extends in the direction of c-axis. In neither the A- nor the B-type complexes does the ligand coordinate to a metal with a sulfur atom.
  • Kohei Shiraishi, Kazuo Sugiyama, Akihiko Sakamoto, Takayuki Otsu
    1988 Volume 61 Issue 3 Pages 783-786
    Published: 1988
    Released: June 27, 2006
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    Senven enantiotropically nematic fumaric ester derivatives, 1-[[(E)-3-alkoxycarbonyl)acryloyl]oxy]-4-(4-methoxyphenylazo)benzene (1), were prepared. The 1 compounds which have unbranched ester alkyl groups showed decreased phase-transition temperatures and narrowed nematic states with the increase in the length of the alkyl chain, while the 1 compounds with terminal branched alkyl groups decrease drastically in nematic thermal stability. From the electro-optical effect originating in the dynamical scattering at the nematic state of the 1 compounds with unbranched ester groups, it was found that both the threshold voltage (Ethres) of deformation and the electro-optial response time (τr) decrease with the decrease in the chain lengh of alkyl groups. In addition, τr is scarcely influenced over the wide temperature range above 12 eV·cm−1 of the electric field.
  • Gorou Arai, Takayuki Ishii, Sumi Yamamoto, Iwao Yasumori
    1988 Volume 61 Issue 3 Pages 787-791
    Published: 1988
    Released: June 27, 2006
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    Heavy metal ions, Ag+, Hg2+, Cd2+, Cu2+, Pb2+, Pd2+, Fe3+, and Pt4+, were each fixed on a conductive redox film of poly(mercapto-p-benzoquinone) or poly(mercaptohydroquinone) by mercaptide formation. Of these mercaptide-modified electrodes, the Pt(IV)-, Pd(II)-, and Ag(I)-modified electrodes possess some catalytic properties for electrochemical hydrogen evolution. These mercaptide-modified electrodes display a nearly Nernstian response to their respective heavy metal ions in aqueous solution and exhibit good durability when stored under appropriate conditions. Especially, the Hg(II)-modified electrode displays an excellent function as an Hg2+ ion sensor. The effect of miniaturization of substrates upon response ability was investigated by using two different-sized Pt wires (0.5 mm and 0.03 mm in diameter).
  • Akira Yamauchi, Masashi Date, Yukiko Yamamoto, Yutaka Hirata, Hideo Ki ...
    1988 Volume 61 Issue 3 Pages 793-797
    Published: 1988
    Released: June 27, 2006
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    In an amphoteric ion exchange membrane-electrolyte system, three independent experiments were carried out, that is, the membrane potential, membrane conductance and concentration of ions within membrane were measured, respectively. The electrolytes adopted in the systems were NaCl, CaCl2, LaCl3. From the analysis of the results, the specific conductance attributed to Donnan salt within membrane was separated. As a result, it was pointed out that the dynamic state of Donnan salt is obviously different from that of salt in aqueous solution. Furthermore, the comparison between the ions constituting Donnan salt and the counterions which interact with the ion-exchange sites suggested us the existance of two different dynamic states on the ions within membrane.
  • Thoru Nakatsuka, Michihiro Nakamura, Takayuki Sano
    1988 Volume 61 Issue 3 Pages 799-802
    Published: 1988
    Released: June 27, 2006
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    The ion sensitive field effect transistor(ISFET) developed for pH measurement was incorporated with the stopped flow apparatus for direct detection of the fast change in the hydrogen ion concentration. By the experiments on the dehydration reaction of carbonic acid, it was proved that the pH sensor has a fast response time (<2 ms) beyond the resolution time of stopped flow apparatus, and the constructed apparatus can be satisfactorily applied to the fast reaction kinetics with the sensitivity for the pH change more than 0.01 pH unit.
  • Katsutoshi Inoue, Yoshinari Baba, Kazuharu Yoshizuka, Tetsuji Oka
    1988 Volume 61 Issue 3 Pages 803-807
    Published: 1988
    Released: June 27, 2006
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    The extraction behavior of palladium(II) from the aqueous ammonium chloride solutions with the title extractant in toluene was investigated in terms of the equilibrium and the kinetics, while the aqueous solubility and the interfacial adsorption equilibrium of the extractant were estimated. The extraction rate of the 1:2 palladium(II)–extractant complex was explained by the interfacial reaction model, in which the ratedetermining steps were assumed to be the elementary reactions between the aquatrichloro- and tetrachloropalladate(II) in the aqueous phase and the extractant molecule adsorbed at the interface.
  • Masumi Ushio, Yoshihiro Sumiyoshi
    1988 Volume 61 Issue 3 Pages 809-814
    Published: 1988
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The wetting of an Al2O3 substrate by liquid gold was investigated by means of the sessile-drop method in an atmosphere of argon. An empirical relation was estabilished between the contact angle and the temperature or surface tension of the liquid drop by the use of the diameter and the height of the sessile drop. The contact angle was constant with time, but decreased linearly with an increase in temperature. The variation in the contact angle with temperature is correlated with the surface tension of the sessile drop. The surface tension of liquid gold was obtained as 933 dyn cm−1 at 1080 °C and 917 dyn cm−1 at 1100 °C and the temperature coefficient of the surface tension of liquid could be estimated to be −0.80 dyn cm−1 °C−1. The critical surface tension (γc) and the surface tension of liquid gold at 0 K of Al2O3LV°) were 20 and 2015 dyn cm−1, respectively.
  • Kunio Ohtsuka, Mitsuru Suda, Mikiya Ono
    1988 Volume 61 Issue 3 Pages 815-820
    Published: 1988
    Released: June 27, 2006
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    Iron(II) hydroxide–(sodium fluoride tetrasilicic mica) intercalation complexes, which have a chloritelike structure, were prepared by titrating iron(II) sulfate solutions in the presence of mica with sodium hydroxide under oxygen-free conditions. The formation of iron(II) hydroxide sheets between the silicate layers was evaluated by chemical analysis, XRD, DTA-TGA, and surface-area measurement. The presence of water is essential for the oxidizing of these complexes to occur at room temperature by air, because the O2 attack on the surface of these iron(II) hydroxide sheets is hindered by the silicate layers. Fine highly dispersed iron metal particles (α-Fe) were formed on the external surface of the silicate by the H2 reduction of the complexes.
  • Yasuhiro Iimura, Tosio Sakurai, Kiyoko Yamamoto
    1988 Volume 61 Issue 3 Pages 821-826
    Published: 1988
    Released: June 27, 2006
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    The crystal and molecular structure of the title compounds, [CoIIICl(tpp)(H2O)], has been determined by means of X-ray diffraction techniques. The compound crystallizes in the monoclinic system; space group P21c. The unit cell has a=13.542(2), b=25.760(2), c=10.423(1) Å, β=99.33(2)°, and Z=4. The cobalt atom is coordinated by four porphyrinato nitrogen atoms, one chlorine atom, and one oxygen atom of water, and is displaced by 0.039(2) Å from the mean plane defined by the four porphyrinato nitrogen atoms towards the axial chlorine atom. The average Co–N(tpp) distance is 1.955(2) Å. The Co–Cl distance is 2.216(1), and the Co–O(water) distance, 1.979(3) Å. The porphyrinato core is significantly ruffled and has an approximate \bar4 symmetry. The [CoIIICl(tpp)(H2O)] molecules are stacked along the c axis by O–H···Cl hydrogen bonds.
  • Masanobu Watanabe, Yuichi Masuda, Izumi Motoyama, Hirotoshi Sano
    1988 Volume 61 Issue 3 Pages 827-833
    Published: 1988
    Released: June 27, 2006
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    Adducts of ruthenocene with Lewis acids, such as HgCl2, SnCl4, and I2, are studied mainly by means of high resolution solid state 13C NMR spectroscopy and 57Fe-Moessbauer spectroscopy. The large low-field shifts found in the 13C-CP-MAS NMR spectroscopy suggest the presence of a direct chemical bond between the ruthenium and the Lewis acids. Ferrocenylruthenocene and biruthenocene give stable adducts with HgCl2 and I2. 57Fe-Moessbauer and 13C-CP-MAS NMR spectroscopic studies suggest the presence of a chemical bond, such as Ru–Hg, Ru–I, in the adducts.
  • Hiromichi Yamada, Shiho Horikawa, Yukio Fujii, Masateru Mizuta
    1988 Volume 61 Issue 3 Pages 835-839
    Published: 1988
    Released: June 27, 2006
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    The extraction of copper(II) with o-, m-, and p-methylbenzoic acids in 1-octanol was carried out at 25 °C and aqueous ionic strength of 0.1 mol dm−3 (NaClO4). In contrast to the extraction with benzoic acid, in which only the monomeric copper(II) benzoate is extracted, the dimeric copper(II) species is also responsible for the extraction of copper(II) with o- and m-methylbenzoic acids in 1-octanol together with the monomeric one. On the other hand, p-methylbenzoic acid has a poorer extracting capability than o- and m-methylbenzoic acids and only the monomeric copper(II) species is responsible for the extraction.
  • Tatsuya Kawamoto, Takaji Yasui, Hisahiko Einaga, Jinsai Hidaka
    1988 Volume 61 Issue 3 Pages 841-848
    Published: 1988
    Released: June 27, 2006
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    The Raman spectra were measured for the bis and mixed type cobalt(III) complexes with ethylenediamine-N-acetate (edma) in an aqueous solution in the skeletal vibration region. The Raman bands could be classified into five vibration modes; a totally symmetric stretching vibration mode in the 510–650 cm−1 region, a stretching vibration mode excluding the totally symmetric one in the 410–540 cm−1 region, a skeletal breathing vibration mode in the 370–490 cm−1 region, a skeletal bending deformation mode in the 270–420 cm−1 region, and a chelate ring deformation mode in the 220–270 cm−1 region. Differences in the skeletal vibrations were observed between the fac and mer isomers for the chelate ring arrangement. Further, differences for the chelate ring arrangement between the Raman spectra of sym-fac and unsym-fac isomers were observed in the skeletal bending deformation mode. The cobalt(III) complexes with the terdentate ligands containing N-methyl group exhibited Raman bands shifted to a lower frequency than those of the corresponding cobalt(III) complexes containing no N-methyl group in the totally symmetric stretching vibration mode region.
  • Terufumi Fujiwara, John C. Bailar, Jr.
    1988 Volume 61 Issue 3 Pages 849-856
    Published: 1988
    Released: June 27, 2006
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    The three isomers of the ion [Co(trien)Cl2]+, where trien=triethylenetetramine, have been synthesized and their interconversion upon heating in the solid state has been studied. The trans isomer changes to the β-cis isomer, which in turn is converted to the α-cis isomer. The changes have been followed by proton NMR spectroscopy. The first change cannot be explained by a twist mechanism. Experiments with the trans monohydrate or hydrochloride in sealed tubes or in an atmosphere of HCl show that the presence of H2O accelerates the conversion of the trans isomer to the cis-β isomer, and the presence of HCl accelerates the conversion of cis-β to cis-α, suggesting that the former conversion takes place through an aquation, followed by anation and for the latter conversion nucleophilic attack of a chloride ion on the cis-β isomer is important.
  • Terufumi Fujiwara, John C. Bailar, Jr.
    1988 Volume 61 Issue 3 Pages 857-860
    Published: 1988
    Released: June 27, 2006
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    The rearrangement of the isomers of dichloro(triethylenetetramine)cobalt(III) bromide and iodide upon heating in the solid state has been studied in relation to the corresponding isomers of the chloride. The behavior of the bromide and iodide has been found to be different from that of the chloride, supporting the existence of anion effects in the solid-state reactions. With respect to the nature of the anions, several factors which are responsible for the differences are discussed in relation to mechanism.
  • Akihiko Ishii, Renji Okazaki, Naoki Inamoto
    1988 Volume 61 Issue 3 Pages 861-867
    Published: 1988
    Released: June 27, 2006
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    A new, convenient method for the synthesis of selenoketones has been reported. The reaction of dimagnesium salts of ketone hydrazones with diselenium dichloride affords an intermediate tentatively assigned as tetraselenides, which are converted into selenoketones by heating in the presence of tributylamine. A comparative study on the reactions of 1,1,3,3-tetramethyl-2-indanselone and the corresponding thioketone with Grignard and organolithium reagents have been carried out. Analysis of the reaction products has revealed that the heterophilic attack of the organometallic reagents is much more significant in the reaction with the selone than with the thione.
  • Hiroki Hamada
    1988 Volume 61 Issue 3 Pages 869-878
    Published: 1988
    Released: June 27, 2006
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    The biotransformation of the enantiomeric pairs of p-menthane and bicyclo[2.2.1] and [3.1.1]heptane derivatives with the cultured cells of Nicotiana tabacum was investigated. It was found that (i) the cultured cells discriminate the enantiomers of p-menthan-2-ol and bicyclo[2.2.1]heptan-2-ol and bicyclo[3.1.1]heptan-3-ol derivatives, and enantioselectively convert these alcohols to the corresponding ketones, (ii) the cells reduce the carbonyl group of p-menthan-2-one derivatives to a high extent, but not that of p-menthan-3-ones, and (iii) the cells discriminate the enantiomers of bicyclo[3.1.1]hept-2-en-4-one (verbenone) and enantioselectively reduce the C–C double bond of the (1S,5S)-enantiomer.
  • Masahiro Minabe, Masaaki Yoshida, Tsukasa Amimoto, Toshihiro Nagata, M ...
    1988 Volume 61 Issue 3 Pages 879-883
    Published: 1988
    Released: June 27, 2006
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    A Fries rearrangement of 4H-cyclopenta[def]phenanthren-1-yl acetate gave 2- and 7-acetyl derivatives. The reaction of isomeric 2-acetoxy compound afforded 1- and 7-acetyl derivatives. The acetyl group of the 3- and 8-acetoxy compounds rearranged into the 2- and 9-positions, respectively. In addition, 1-, 2-, 3-, 4-isopropyl compounds were derived from the corresponding acetyl derivatives.
  • Chung-gi Shin, Yasuchika Yonezawa, Takumi Obara, Hiroaki Nishio
    1988 Volume 61 Issue 3 Pages 885-891
    Published: 1988
    Released: June 27, 2006
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    Various N-benzyloxycarbonyl (Cbz) O-protected dehydrotyrosine (ΔTyr) esters have been successfully synthesized mainly via two routes, in which reactions of (diethoxyphosphinyl)glycine ester with p-substituted benzaldehyde were included. Subsequent hydrolyses of the esters under various alkaline conditions were carried out in order to produce corresponding Cbz-ΔTyr-OH derivatives, which were further converted with thionyl chloride to give N-carboxy dehydrotyrosine anhydrides [ΔTyr·NCA]. In addition to these topics, the transformation of ΔTyr·NCA to various kinds of ΔTyr derivatives and a discussion on the configurational determination of all the new compounds are presented.
  • Hiroyasu Inoue, Tadamitsu Sakurai, Koichi Tomiyama, Ryo Sano, Masahiro ...
    1988 Volume 61 Issue 3 Pages 893-898
    Published: 1988
    Released: June 27, 2006
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    Phthalazine undergoes dual photoreactions to simultaneously give two photoproducts, 1,2-dihydrophthalazine (1) and 1,1′,2,2′-tetrahydro-1,1′-biphthalazine (2), upon ultraviolet light irradiation in 2-propanol under nitrogen. There occurs neither photochemical nor thermal interconversion between 1 and 2; these compounds are formed independently from a common intermediate through different reaction pathways. The results of quenching and sensitization experiments for both the reactions and the phosphorescence emission show that the lowest excited singlet and triplet states of phthalazine participate in the formation of 1 and 2, respectively. The observed photochemical behaviors under various conditions lead us to propose a reaction mechanism: Phthalazine is photoreduced in the S1 state to form 1,2-dihydro-1-phthalazinyl radical. The resulting radical in a solvent cage undergoes a subsequent hydrogen abstraction to form 1. On the other hand, the same radical produced in the T1 state escapes from the solvent cage to cause a dimerization which affords 2.
  • Tadashi Shiraiwa, Yujin Sado, Mitsuo Inoue, Keiji Sakamoto, Hideya Miy ...
    1988 Volume 61 Issue 3 Pages 899-903
    Published: 1988
    Released: June 27, 2006
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    Gibbs energies of formation of racemate, binary melting point diagrams, and ternary solubility diagrams indicate that (±)-propylammonium ((±)-PA salt) and (±)-1,1,3,3-tetramethylbutylammonium ((±)-TMB salt) hydrogen malates are conglomerates at room temperature, whereas (±)-TMB salt forms a racemic compound at its melting point. Free energies of critical nucleation in supersaturated solutions were examined to resolve (±)-PA and -TMB salts efficiently by preferential crystallization. Successive preferential crystallization of (±)-PA salt in methanol at 10 °C and that of (±)-TMB salt in water give (+)- and (−)-PA and -TMB salts with about 90% optical purity. Optically pure (+)- and (−)-malic acids are obtained from purified (−)- and (+)-salts.
  • Yoji Hashida, Kazuhiro Kubota, Shizen Sekiguchi
    1988 Volume 61 Issue 3 Pages 905-909
    Published: 1988
    Released: June 27, 2006
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    The azo coupling reaction of p-methoxybenzenediazonium tetrafluoroborate with N,N-dimethylaniline has been investigated in a water-1,2-dichloroethane system. It has been found that, among the several additives examined, the phenolate ion, generated from picric acid or 2,4-dinitro-1-naphthol, acted as an effective phase-transfer catalyst. Further, the reaction of p-diethylaminobenzenediazonium tetrafluoroborate with dimedone, an active methylene compound, has also been investigated in the same two-phase system; a remarkable acceleration in the rate was observed in the presence of tetraalkyl onium salts, and even in their absence.
  • Takashi Matsumoto, Sachihiko Imai, Naoya Yamamoto
    1988 Volume 61 Issue 3 Pages 911-919
    Published: 1988
    Released: June 27, 2006
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    The reactions of four naphthols (1-naphthol (1), 2-naphthol (2), 4-isopropyl-1-naphthol (18), and 3-isopropyl-2-naphthol (19)) with benzoyl peroxide were examined under two reaction conditions (A and B). Each of the naphthols 1, 2, 18, and 19 was oxidized with 0.95 equivalent moles of benzoyl peroxide at room temperature for 24 h (condition A) to give mainly the corresponding ortho-benzoyloxylated product which was isolated in moderate yield as an equilibrium mixture, resulting from its trans -benzoylation. The naphthols 18 and 19 were also oxidized with 2.25 equivalent moles of benzoyl peroxide at room temperature for 48 h (condition B) to give mainly 2,2-bis(benzoyloxy)-4-isopropyl-1(2H)-naphthalenone and 2,2-bis(benzoyloxy)-3-isopropyl-1(2H)-naphthalenone in good yields. The oxidations of 1 and 2 under condition B produced the same product, 2,2-bis(benzoyloxy)-1(2H)-naphthalenone, in low yields.
  • Yoichi Taguchi, Koshin Yanagiya, Isao Shibuya, Yasuo Suhara
    1988 Volume 61 Issue 3 Pages 921-925
    Published: 1988
    Released: June 27, 2006
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    The reaction of 2,2-dimetyloxirane with carbon disulfide in the presence of triethylamine was accelerated under high pressure to give 5,5-dimethyl-1,3-oxathiolane-2-thione in a high yield, while 2-hexyloxirane under the same reaction condition formeds 4-hexyl-1,3-dithiolane-2-thione (2b) as the main product and 5-hexyl-1,3-oxathiolane-2-thione (1b) as a minor product. A feasible mechanism for this formation is that 1b and 2-hexylthiirane (4b) are produced in the first stage of reaction, and that 2b is then formed by the reaction of 1b or 4b with carbon disulfide. In reactions of a variety of oxiranes with carbon disulfide, 1,3-dithiolane-2-thiones were obtained in high yields under 800 MPa at 100 °C within 20 h. Concerning the effect of substituents in oxiranes, the selectivity for product 2b is in the decreasing order; 2-phenyl->2-methyl->2-ethyl->2-hexyl->2,3-tetramethylene->2,2-dimethyl->2-(chloromethyl)-. Tertiary amines, such as N,N-dimethylethylamine, pyridine, and N-methylmorpholine, serve as good catalysts for the reaction.
  • Keisuke Kurita, Satoyuki Chikaoka, Mami Kamiya, Yoshiyuki Koyama
    1988 Volume 61 Issue 3 Pages 927-930
    Published: 1988
    Released: June 27, 2006
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    N-Acetylation on chitosan has been studied in a highly swelled state with acetyl chloride in comparison with that with acetic anhydride under various conditions to establish the general possibility and scope of the acylation reactions on chitosan and other polysaccharides. A highly swelled chitosan precipitate prepared by pouring a chitosan solution in aqueous acetic acid/methanol into pyridine is quite suitable for efficient modifications, and the reaction with either acylating reagent proceeded smoothly and reproducibly under mild conditions. Although acetic anhydride is generally more appropriate in protic solvens, acetyl chloride is effective and advantageous especially in pyridine containing only small amounts of protic solvents.
  • Toshihiko Migita, Kazuya Hongoh, Hiroyuki Naka, Setsuko Nakaido, Masan ...
    1988 Volume 61 Issue 3 Pages 931-938
    Published: 1988
    Released: June 27, 2006
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    Azidoformate reacted with allylic ethers to give 1-alkoxy-1-(alkoxycarbonylimino)alkane under catalysis by PdCl2(PhCN)2. The same imines were formed almost quantitatively by noncatalyzed reaction of the azide with the corresponding vinylic ethers. The rate of the catalyzed reaction was found to be first order each in the allylic ether and in the azide. Easiness of the imine formation from the allylic ethers depended on the nature of azide, decreasing in the order of N3SO2Me>N3CO2Me>N3Ph. Based on these results the most probable mechanism for the catalyzed reaction is proposed.
  • Keiichiro Ogawa, Hiroshi Suzuki, Motoko Futakami, Shin Yoshimura, Tosi ...
    1988 Volume 61 Issue 3 Pages 939-943
    Published: 1988
    Released: June 27, 2006
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    The crystal structure of the title compound was determined by X-ray diffraction. The crystals have monoclinic symmetry with a=13.481(5), b=8.285(5), c=l3.092(3) Å. β=96.24(3)°, and space group P21n with Z=4. The final R-factor was 0.065 for 2191 independent reflections. The torsion angles of the C–Ph bonds are 47.4(4) and 44.4(4)°. The cyclohexene rings have approximate twist-boat conformations. The molecular structure in the crystal is compared with that in the solution phase, that of (E)-stilbenes, and the results of the molecular mechanics calculations. It is also discussed in relation to the molecular packing.
  • Kazuhiko Ozutsumi, Shin-ichi Ishiguro, Hitoshi Ohtaki
    1988 Volume 61 Issue 3 Pages 945-951
    Published: 1988
    Released: June 27, 2006
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    The solvation structure of copper(II) ion in N,N-dimethylformamide (DMF) and N,N-dimethylformamide–acetonitrile (AN) mixtures has been investigated by means of X-ray diffraction at 25 °C. The X-ray scattering data for the copper(II) perchlorate DMF solution were well-interpreted in terms of the presence of the axially elongated octahedral [Cu(dmf)6]2+ ion in DMF. Among the six DMF molecules, four of them are at the distance of 203(3) pm at the equatorial position and the other two are at 243(5) pm at the axial one. On the other hand, in copper(II) perchlorate DMF–AN solutions with the CdmfCCu mole ratios of 5.308 and 7.435, where Ci denotes the total concentrations of species i, the copper(II) ion is coordinated with four DMF molecules within the square-plane and with no solvent molecule along the axis of the plane. The equatorial Cu–O bond length is 200(1) pm and practically the same as that within the [Cu(dmf)6]2+ ion in DMF. In copper(II) nitrate DMF solutions (1.086 and 1.500 mol dm−3), a nitrate ion binds to copper(II) ion at the equatoral position and the distorted octahedral [CuNO3(dmf)5]+ complex is formed.
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