Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 56 , Issue 7
Showing 1-50 articles out of 71 articles from the selected issue
  • Kinya Iijima, Shuzo Shibata
    1983 Volume 56 Issue 7 Pages 1891-1895
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The molecular structure of trimethylamine–boron triiodide (CH3)3N·BI3 has been determined from gas electron-diffraction data. The molecular parameter values and their uncertainties are rg(B–I)=2.245±0.004 Å, rg(N–B)=1.663±0.013 Å, rg(C–N)=1.497±0.005 Å, rg(C–H)=1.103±0.010 Å, ∠IBI=108.6±0.4°, and ∠CNC=106.0±0.8°. The potential barrier around the N–B bond has also been estimated to be about 3.5 kcal mol−1 (1 cal=4.184J).
  • Katsuko Takaizumi, Toshiki Wakabayashi
    1983 Volume 56 Issue 7 Pages 1896-1902
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Density measurements were carried out at six temperatures between 1 and 55 °C for three series of aqueous mixed electrolyte solutions, each of which contained (n-Bu)4PCl and Ph4PCl with the mole ratios, 3:1, 1:1, and 1:3, respectively. The mixed solutions are assumed to be the model solutions of the phosphonium chlorides, (n-Bu)4−n PhnPCl(n=1,2, and 3), with respect to the pair-wise interactions between the cations, for which a model has been proposed in a previous paper. The volume B-coefficients(Bv) determined for the model salts are in good agreement with those for the corresponding pure salts and those reproduced by the equation derived from the model. The results indicate that the phenyl groups affect weakly the butyl cospheres in both the intermolecular processes and intramolecular processes and that among the ion-ion interactions the cation-cation interactions are the main factor for determining the Bv′s. These can be decomposed into three parts, arising from the butyl-butyl, phenyl-phenyl, and butyl-phenyl interactions.
  • Tomoyoshi Seto, Motomichi Inoue, Michiko B. Inoue, Daiyu Nakamura
    1983 Volume 56 Issue 7 Pages 1903-1906
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Electron spin resonance spectra were recorded on highly conducting CuL(TCNQ)2 (L: 2,2′-bipyridine or ethylenediamine) at different temperatures. The observed g values increased with decreasing temperature. On the basis of the g shift and the static susceptibility observed, a local magnetic susceptibility contributed from Cu and that from TCNQ, were evaluated individually. The local Cu susceptibility is of the Curie type. The Curie constant indicates that each Cu atom carries 0.05 umpaired electron on the average in Cu(bpy)(TCNQ)2 and 0.07 in Cu(en)(TCNQ)2: the average oxidation number of copper is equal to 1.05 in the former and 1.07 in the latter. The local susceptibility of TCNQ can be interpreted by a narrow band model in which the susceptibility is given by the sum of the Curie term and a temperature-independent paramagnetic term.This suggests that the TCNQ arrays have inherently metallic nature.
  • Yuji Yamaguchi, Takashi Nogami, Hiroshi Mikawa, Itsumaro Kumadaki, Yos ...
    1983 Volume 56 Issue 7 Pages 1907-1911
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Charge-transfer interaction of a series of trifluoromethylated benzenes with several donor molecules was investigated by measuring electronic absorption and fluorescence spectra. Half-wave reduction potentials of acceptors were determined by cyclic voltammetry. Charge-transfer absorption bands were observed for several systems. Thermal one-electron transfer reactions were observed for solutions of hexakis(trifluoromethyl)benzene and several aromatic amines even in nonpolar solvents. Charge-transfer fluorescence was observed for solutions of hexakis(trifluoromethyl)benzene or tetrakis(trifluoromethyl)benzene and weak donor molecules such as benzene, toluene, or p-xylene.
  • Kazuo Tsutsumi, Yoshio Mitani, Hiroshi Takahashi
    1983 Volume 56 Issue 7 Pages 1912-1916
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Heats of adsorption of ammonia and pyridine on H–Y zeolites and other solids were measured using a microcalorimeter in the temperature range of 313 to 673 K. Infrared spectra of adsorbed ammonia and pyridine were obtained in order to interpret the calorimetric data. There appeared two kinds of the temperature dependence of heats of adsorption. One is that heats of adsorption on H–Y5.0 and silica-alumina do change with coverage to a greater extent at high temperature range (above 473 K) than low temperature range. The difference in the shape of the heat curves was found to be attributable to the difference in the selectivity of adsorption at different temperatures, that is, adsorption occurred on stronger acidic sites is preference to weaker or non-acidic sites in the high temperature range, while random adsorption occurred simultaneously on acidic and non-acidic sites in the low temperature range. The other kind of temperature dependence was recognized to appear as a slight decrease in heats of adsorption with a temperature rise, which were observed in cases of ammonia adsorption on H–Y zeolites above 473 K and on Na–Y and silica above 313 K while the shapes of heat curves were similar to one another irrespective of the adsorption temperature. Such decrease may be attributed to the fact that the temperature dependence of the heat of adsorption was thermodynamically defined by the difference in molar heat capacity between adsorbed state and gaseous state.
  • Yoshio Mitani, Kazuo Tsutsumi, Hiroshi Takahashi
    1983 Volume 56 Issue 7 Pages 1917-1920
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Differential heats of adsorption of bases on H–Y zeolite were measured at 473 K and separated into those evolved at 3640 and 3550 cm−1-OH sites respectively by a combined use of calorimetric and IR measurements, and then the acid strength of two OH sites was compared each other. In case of pyridine, heats of adsorption were larger on OH sites at 3640 cm−1 than 3550 cm−1, which was in agreement with the results obtained by many authors by IR measurements. However, heats of adsorption on 3640 cm−1-OH sites were only slightly higher than those on 3550 cm−1-OH sites in case of ammonia, and almost the same in case of piperidine. The difference in heats of adsorption between the OH sites was explained by positional difference between the two OH sites, molecular size of the titrated bases and proton mobility induced by a strong base. The order of the strength of bases was determined by replacing a base molecule with another one on H–Y zeolite as follows; piperidine>pyridine>ammonia. This differs from the order expected from their pKa values in solution.
  • Yoshio Mitani, Kazuo Tsutsumi, Hiroshi Takahashi
    1983 Volume 56 Issue 7 Pages 1921-1923
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Heats of adsorption of pyridine and ammonia were respectively measured on aluminum deficient H–Y zeolites using a microcalorimeter at 473 K. The calorimetrically determined acidity was discussed in relation to the positional difference between 3640 and 3550 cm−1-OH acidic sites and compared with the catalytic activity. Dealumination generally brings about a decrease in the acid site concentration. However, the extent of the decrease varied with the kind of titrated base and a significant change was observed in the ratio of acid site concentration when titrated with pyridine. This may be explained by the fact that the pore size of the zeolite becomes widely distributed as dealumination proceeds; 3550 cm−1-OH sites in supercages must become accessible to such a large molecule as pyridine. Also observed with dealumination was a slight increase in the heat of adsorption from initial to the middle stage of adsorption, which reflected the enhancement in acid strength of each OH site. The catalytic activity for cumene cracking increased with dealumination, which agreed with the acidity determined by the adsorption of pyridine rather than ammonia.
  • Hiroyuki Shinoda, Tomoo Miyazaki
    1983 Volume 56 Issue 7 Pages 1924-1929
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The bond moment theory was reinvestigated by use of localized molecular orbitals derived from INDO canonical orbitals. Bond moments were defined in terms of localized molecular orbital and, together with their derivatives with respect to a C–H stretching motion, were evaluated for some simple molecules; the bond moments of acetylene and hydrogen cyanide in the C–H bending geometry were also calculated. It is concluded that the first-order approximation for the bond moment theory is inadequate to interpret infrared absorption intensity. In the C–H stretching vibration the change in trans-sited bond moment is considerably large.
  • Kunio Tamaki, Y\={o}ko Ohara, Masahiro Inabe, Tetsushi Mori, Fumio Num ...
    1983 Volume 56 Issue 7 Pages 1930-1934
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The apparent molar volumes, viscosity B coefficients, heats of solution, and surface activity of sodium alkanesulfonates (RSO3Na, methyl to hexyl) in water were measured. The limiting apparent molar volumes at 25 °C increase with the number of carbon atoms in the alkyl chain; the increment per methylene group is about 16 cm3mol−1. The viscosity B coefficients of MeSO3Na and EtSO3Na increase with the temperature, while those of n-BuSO3Na decrease with an increase in the temperature. The changes in heat capacity for dissolution in water, ΔCpo, as calculated from the heats of solution at 15, 25, and 35 °C, were negative for MeSO3Na and EtSO3Na, while the ΔCpo values for n-PrSO3Na and higher homologs were positive. MeSO3Na raises the surface tension of water, while EtSO3Na and higher homologs reduce it. The structural changes in the solvent water upon the dissolution of sodium alkanesulfonates are discussed in comparison with those of sodium alkyl sulfates previously reported.
  • Jun-ichi Aihara
    1983 Volume 56 Issue 7 Pages 1935-1943
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Aromatic hydrocarbons have thermodynamically stable cyclic conjugated systems. There is a tacitly accepted view that not only aromatic stabilization but also kinetic stability arise from the same cyclic conjugation of π electrons. In order for this view to be examined criticaly, two reactivity indices, i.e., localization energy and superdelocalizability, were adopted for a variety of cyclic conjugated hydrocarbons, and were compared with those defined for their olefinic reference structures. Interestingly, it was found that chemical reactivity of some constituent carbons might often overcome aromatic stabilization of an entire conjugated system. Not a few nonbenzenoid aromatic hydrocarbons were predicted to have reactive carbons which are olefinic in reactivity. These hydrocarbons constitute unstable aromatic compounds. Thus, it has been clarified that thermodynamic and kinetic stabilities do not always concur in the case of nonbenzenoid hydrocarbons.
  • Michiya Itoh, Yukio Hanashima, Naoko Wada, Ichiro Hanazaki
    1983 Volume 56 Issue 7 Pages 1944-1949
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The excitation energy dependence of the intramolecular exciplex formation and the electronic relaxation has been studied in the collision-free vapor of 1-(9,10-dicyano-2-anthryl)-3-(pentamethylphenyl)propane. The fluorescence quantum yields and lifetimes of the 9,10-dicyanoanthryl moiety and the intramolecular exciplex in the collision-free vapor were observed to depend on the excitation energy within the S1 absorption band. From the quantum yields and the decay rate constants, the excitation energy dependence of the association and dissociation rate constants of the intramolecular exciplex formation were determined. The association rate constant of the exciplex formation increases more remarkably with increasing excitation energy than the nonradiative rate constants of 9,10-dicyanoanthryl moiety and the exciplex. The excitation energy dependence of the association rate constant was discussed in terms of the nonradiative transition from the initial optical state to the final exciplex and the level density of the final state, which were calculated in the simple model system by means of the semi-classical mechanics.
  • Yoshiteru Hayami, Makoto Aratono, Shozo Uryu, Kinsi Motomura, Ryohei M ...
    1983 Volume 56 Issue 7 Pages 1950-1953
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    In order to show that our thermodynamic treatment [J. Colloid Interface Sci., 87, 333 (1982)] is useful in the study on the monolayer penetration, the surface tension has been measured with the system consisting of pentadecanoic acid monolayer and dodecylammonium chloride solution. Applying the thermodynamic equations to the experimental data, the surface density of dodecylammonium chloride, and entropy and energy of penetration have been estimated numerically. It has been found that the surface density, entropy, and energy all decrease with increasing the concentration of film-forming substance. Therefore, it has been concluded that the penetration of monolayer of this system is caused by the decrease of the energy of penetration which compensates the decrease of the entropy of penetration.
  • Koichiro Miyajima, Masahiro Sawada, Masayuki Nakagaki
    1983 Volume 56 Issue 7 Pages 1954-1957
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Viscosities, apparent molar volumes, and activity coefficients of aqueous solutions for D-glucose, maltose, and maltotriose were measured at various concentrations. The signs of Bst, the increment of viscosity B-coefficient arising from structural change of water, were positive for these three saccharides, and the signs of dBdT, the temperature dependence of B, were negative. The magnetudes of Bst and |dBdT| increased with the number of glucose residue. Activity coefficients were larger than unity and increased with concentration, and their magnitudes also increased with the number of glucose residue. These results indicate that D-glucose, maltose, and maltotriose are structure forming solutes, and that their abilities lie in the order of D-glucose<maltose<maltotriose.
  • Kunio Furusawa, Kazuaki Yamamoto
    1983 Volume 56 Issue 7 Pages 1958-1962
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Critical experimental data on competitive adsorption and exchangeability of adsorbed polymer are produced under the various conditions using the gel permeation chromatography technique. It is apparent that the competitive effects and the exchangeability were found to depend not only on the molecular weight of the polymer, but also on the concentration of each component at which the corresponding adsorption is carried out. This can be explained as follows; the conformation of the adsorbed polymer would be influenced extensively by the polymer concentration in bulk. The polymer molecules adsorbed from a dilute solution would take on a flat conformation being rich in train segments, but the polymer layer formed under a concentrated solution would occupy a small of sites and adopt an extended loop configuration which would be desorbed more easily than the flat one. Also, in the mixed sample the effects of adsorption Kinetics play an important role on the structure of the adsorption layer, because at first the surface is convered by an adsorption layer of small components due to its rapid adsorption rate.
  • Masashi Hojo, Yoshihiko Imai
    1983 Volume 56 Issue 7 Pages 1963-1967
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    An acetate ion (A) formed a homoconjugated species, A (HA)2, with 2 molecules of acetic acid (HA) in the presence of a large excess of HA in an acetonitrile solution. In the presence of both acetic acid and LiClO4, one molecule of HA was derived from A (HA)2 by means of a lithium ion to from an ion-paired species, HA2Li, as follows: A(HA)2+Li+\oversetKex\ ightleftharpoonsHA2Li++HA. The equilibrium constant, Kex, was evaluated as 1.1×104 from the shift in the anodic half-wave potential of the acetate ion. As for the benzoate ion (A′) and HA′, similar reactions occured, and the constant of the exchange reaction was evaluated as 6×103. The effect of the sodium ion and HA (or HA′) on the A (or A′) ion was complicated. On the other hand, the presence of [M(A′)2] (M=Li, Na, K) was proved by the shift of the cathodic wave of the alkali metal.The addition of water caused the apparent stability constant of [Li(A′)2] to decrease extremely.
  • Joichi Ueda, Kyoko Kadowaki
    1983 Volume 56 Issue 7 Pages 1968-1971
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Procedures are described for the spectrophotometric determination of palladium and bismuth(III) with Semimethylxylenol Blue (SMXB). SMXB reacts with palladium and bismuth(III) to form reddish-violet 1:1 complexes. The optimum pH ranges for the color development are pH 1.0–1.7 for palladium and pH 1.0–1.4 for bismuth(III). The absorption maxima of the colored solutions lie at 565–568 nm and at 568–570 nm, respectively. Beer’s law is obeyed over the range of 0.4–3.2 μg cm−3 of palladium and 0.4–4.0 μg cm−3 of bismuth(III), and the sensitivities of the determinations are 4.0×10−3 μg Pd cm−2 and 6.1×103 μg Bi cm−2 for 0.001 of absorbance. For the palladium determination, gallium, tin(IV), bismuth(III), scandium, zirconium, and iron(III) interfere, but tin(IV), scandium, zirconium, and iron(III) can be masked by the addition of fluoride. For the bismuth(III) determination, gallium, tin(IV), scandium, zirconium, and iron(III) interfere, but the effect of iron(III) is eliminated by the addition of L-ascorbic acid, and tin(IV) and scandium can be masked by fluoride. A consecutive determination of palladium and bismuth(III) by the difference of the rates of color developments for their complexes was also studied.
  • Masataka Moriyasu, Yohei Hashimoto, Masaru Endo
    1983 Volume 56 Issue 7 Pages 1972-1977
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The restricted rotation about carbon-nitrogen bonds of unsymmetrical palladium(II) dithiocarbamate chelates has been investigated by high-performance liquid chromatography. At higher temperatures, the rotation is so rapid that two rotamers have not been distinguished, and a single sharp peak has appeared on chromatograms, whereas at lower temperatures, they have been separated. The activation energy of the rotation of palladium(II) dithiocarbamate (ΔH\ eweq=83±5 kJ mol−1 for Pd(C6H5CH2CH2NHCSS)2) is smaller than usual values of the energy barrier to rotate double bonds, but larger than those to rotate single bonds.
  • Kouzou Yoshitani, Manabu Yamamoto, Yuroku Yamamoto
    1983 Volume 56 Issue 7 Pages 1978-1981
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The partial molal volumes, \barV°, of [M(phen)3]Cl2 (M=Fe(II), Co(II), Ni(II), Cu(II), and Zn(II)) and 1,10-phenanthroline were determined from density measurements at 25 °C. From the values for \barV° of [M(phen)3]2+, M2+ and phen the volume changes for complex formation of [M(phen)3]2+, Δ\barV°, were caluculated. Values for \barV° of [M(phen)3]Cl2 varied from 445.1 cm3 mol−1 for [Fe(phen)3]Cl2 to 458.1 cm3 mol−1 for [Zn(phen)3]Cl2 and were in the order, [Fe(phen)3]2+<[Co(phen)3]2+>[Ni(phen)3]2+<[Cu(phen)3]2+<[Zn(phen)3]2+. The Δ\barV° of [Fe(phen)3]2+ was significantly small, 4.7 cm3 mol−1. While those of other metal chelate ions were similar values, ca. 20 cm3 mol−1. The smaller Δ\barV° of [Fe(phen)3]2+ is considered to be due to the spin change from the high-spin aqua ion, [Fe(OH2)6]2+, to the low-spin complex ion, [Fe(phen)3]2+.
  • Hiroyuki Ohbo, Hiroshi Okazaki, Katsuhiko Miyoshi, Hayami Yoneda
    1983 Volume 56 Issue 7 Pages 1982-1988
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The crystal structure of the title compound d-quinidinium (−)546-[Cr(ox)2(phen)]·H2O has been determined by a single-crystal X-ray analysis and refined to R=0.078 for 2172 reflections. The crystals are orthorhombic, space group P212121 with unit cell dimensions of a=9.943(2), b=11.265(2), c=30.716(6) Å, and Z=4. The known configurations of d-quinidinium ion revealed that (−)546-[Cr(ox)2(phen)] has a Δ configuration in accord with the earlier assignment based on its CD spectrum. Following characteristics were noted with regard to intermolecular interactions in the crystal; i) complex anions are linked with one another through the hydrogen bonds to intervening water molecules, to form chains along two-fold screw axes parallel to the a-axis, ii) intermolecular hydrogen bonds connect the complex anion closely with d-quinidinium cation which is further hydrogen-bonded to each other forming infinite chains along two-fold axes parallel to the b-axis, and iii) partial stacking is observed between aromatic phen and quinoline rings. These interaction modes were discussed in relation to the Pfeiffer Effect of the corresponding system in water.
  • Hideo Doine, Yasuhisa Ikeda, Hiroshi Tomiyasu, Hiroshi Fukutomi
    1983 Volume 56 Issue 7 Pages 1989-1994
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The exchange reaction of N,N-dimethylformamide (dmf) in [UO2 (dmf)5]2+ ion and the anation reactions by SCN and N3 have been studied by the NMR method in CD2Cl2 and the stopped-flow method in DMF, respectively. For the dmf exchange reaction, rate=(kd+kIKos[DMF])[UO2(dmf)52+]/(1+Kos[DMF]), where kd, kI, and Kos are (1.30±0.21)×102 s−1, (2.94±0.07)×103 s−1, and 1.59±0.11 mol−1 kg at −50 °C, respectively. For the anation reactions by SCN and N3, the pseudo-first-order rate constant (kobsd) is expressed by kobsd={k−1+(k1+k−1)Kos[X]}⁄(1+Kos[X]) (X=SCN and [UO2(dmf)5]2+ for the anation reactions by SCN and N3, respectively). The values of k1, k−1, and Kos at 25 °C are 1.95×102 s−1, 4.27×102 s−1, 1.48×102 M−1 (1 M=1 mol dm−3), and 1.64×103 s−1, 3.72×102 s−1, 1.80×102 M−1 for SCN and N3, anation reactions, respectively. These results suggest that the substitution reaction in [UO2(dmf)5]2+ ion proceeds through the associative interchange mechanism. The difference of reactivities for SCN and N3 toward [UO2(dmf)5]2+ ion seems to be related to the pKa values for acids, HSCN and HN3.
  • Katsuhiko Wakayama, Ken-ichi Okamoto, Hisahiko Einaga, Jinsai Hidaka
    1983 Volume 56 Issue 7 Pages 1995-1999
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The (diethylenetriamine)(L-penicillaminato)cobalt(III) complex, [Co(L-pen)(dien)]+, was chromatographically separated into three isomers, trans(NiN), trans(NiO) and trans(NiS). Each of these gave a corresponding isomer of the (diethylenetriamine)(S-methyl-L-penicillaminato)cobalt(III) complex, [Co(L-smp)(dien)]2+, by the reaction with dimethyl sulfate. The (triammine)(S-methyl-L-penicillaminato)cobalt(III) complex was also derived from the corresponding L-pen complex, [Co(L-pen)(NH3)3]+. The absorption and CD spectra of the L-pen complexes were compared with those of the L-smp ones to specify the geometrical configurations. The L-pen complexes exhibited characteristic absorption behavior and CD spectra in the region of (14–30)×103 cm−1.
  • Lih-Fen Chang, Masatada Satake, B. K. Puri, Saswati P. Bag
    1983 Volume 56 Issue 7 Pages 2000-2003
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A new procedure for the spectrophotometric determination of iron(II) after collection of its ternary complex with 1,10-phenanthroline and tetraphenylborate on microcrystalline naphthalene is described. In the presence of tetraphenylborate, the tris(1,10-phenanthroline)iron(II) ion is quantitatively collected on microcrystalline naphthalene as the ion-association complex. The system conforms to Beer’s law over the range 3–50 μg of iron in 10 ml of the solvent. The molar absorptivity was 1.2×104 l mol cm−1 at 514 nm. The effect of various factors, such as wavelength, pH, amounts of reagent and naphthalene, shaking time, and diverse ions, were also studied. The procedure method was satisfactorily applied to the determination of iron in standard aluminium alloy, aluminium, and magnesium metals.
  • Keiichi Sato, Shuichiro Yamaguchi, Hiroaki Matsuda, Takeo Ohsaka, Nobo ...
    1983 Volume 56 Issue 7 Pages 2004-2008
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    An electron transfer process of [Mo(CN)8]4−⁄3− redox couple at the graphite electrode/protonated poly(4-vinylpyridine) (PVP) interfaces was examined by the normal pulse voltammetry. It became apparent that electrode reaction of the electroactive species confined in the polymer film on electrode surface obeys the conventional Butler-Volmer equation which characterizes the ordinary electrode reaction at electrode/solution interface. From the analysis of the dependences of the current-potential curves upon the sampling time the relevant kinetic parameters (i.e., the standard rate constant, k° and the transfer coefficient, α) of the electrode reaction were evaluated. The value of k° decreased from 9.7×10−4 to 1.7×10−4 cm s−1 and the value of α was almost constant (0.50), when the molar ratio of the incorporated [Mo(CN)8]4− to pyridine group of the PVP film, ΓMΓPVP, was increased from 0.0025 to 0.22. The apparent diffusion coefficient, Dapp, for the process of charge transport within the film was also determined from the dependence of the limiting current upon the sampling time. The value of Dapp decreased from 4.4×10−8 to 2.5×10−9 cm2 s−1, when the ratio ΓM/ΓPVP was increased from 0.0025 to 0.22.
  • Makoto Nitta, Akihiko Omata, Hazime Nakatani
    1983 Volume 56 Issue 7 Pages 2009-2012
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The oxidations of 1,5-dimethyl- and 1,3,5-trimethyl-6-methylenetricyclo[3.2.1.02,7]oct-3-en-8-ones with 3-chloroperbenzoic acid or thallium(III) acetate resulted in the formation of 1′,5′-dimethyl and 1′,3′,5′-trimethylspiro[oxirane-2,6′-tricyclo[3.2.1.02,7]oct[3]en]-8′-ones (2a and 2b). The oxidation occured stereoselectively on the exocyclic double bond from the exo-side. The photochemical reactions of 2a and 2b resulted in the formation of 4,8-dimethyl- and 4,6,8-trimethyl-3,4-dihydro-1H-2-benzopyran-3-ones, both of which would be derived from an ene-type reaction of the ketene intermediate with the exoxide ring involved in the [4π+2σ] electronic system. The intermediacy of the ketene was assessed by low-temperature infrared spectroscopy as well as by a trapping experiment, the mechanistic pathways were confirmed by conducting the photoreaction in deuterated methanol.
  • Takashi Matsumoto, Sachihiko Imai, Shoji Takeda, Masanori Mitsuki
    1983 Volume 56 Issue 7 Pages 2013-2017
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The structures of nellionol and dehydronellionol were revised respectively to 6α,11,12,16-tetrahydroxyabieta-8,11,13-trien-7-one (12) and 6,11,12,16-tetrahydroxyabieta-5,8,11,13-tetraen-7-one (13) by the following syntheses. A mixture of (15R)- and (15S)-12-methoxyabieta-8,11,13-trien-16-ol, prepared from 13-acetyl-12-methoxypodocarpa-8,11,13-triene, was converted into 11,12,16-triacetoxyabieta-8,11,13-trien-7-one (22) via 16-acetoxy-12-benzoyloxyabieta-8,11,13-trien-11-ol. Treatment of 22 with isopropenyl acetate, followed by oxidation with m-chloroperbenzoic acid and subsequent acetylation, afforded 6α, 11,12,16-tetraacetoxyabieta-8,11,13-trien-7-one, which was hydrolyzed with dilute hydrochloric acid to 12. The ketone 22 was also converted into 13 via 11,12,16-triacetoxyabieta-8,11,13-trien-6-one. The spectral data of 12 and 13 were in good agreement with those of natural nellionol and dehydronellionol.
  • Takashi Matsumoto, Yoshinori Endo, Masaru Okimoto
    1983 Volume 56 Issue 7 Pages 2018-2022
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Reduction of abieta-8,11,13,-trien-6-one with lithium aluminium hydride, followed by treatment with lead tetraacetate and iodine, affored 6β,20-epoxyabieta-8,11,13-triene. This was converted into a separable mixture of abieta-8,11,13-trien-20-ol (13) and 5βH-abieta-8,11,13-trien-20-ol (14) by a series of reactions; ether cleavage with acetic p-toluenesulfonic anhydride, catalytic hydrogenation, and reduction with lithium aluminium hydride. Acetylation of 13 and 14 gave the corresponding acetates, 20-acetoxyabieta-8,11,13-triene (11) and 20-acetoxy-5βH-abieta-8,11,13-triene (12). Friedel-Crafts acylation of 11 with acetyl chloride in the presence of anhydrous aluminium chloride afforded 20-acetoxy-12-acetylabieta-8,11,13-triene, which was converted into pisiferol by oxidation with m-chloroperbenzoic acid and subsequent treatment with lithium aluminium hydride. The synthetic pisiferol was oxidized with Jones reagent to give pisiferal. Similarly, 5βH-abieta-8,11,13-triene-12,20-diol was synthesized from 12. Conversion of the cis A/B ring junctions in 12 into the trans ones is also described.
  • Iwao Shimizu, Hiroshi Umezawa, Toshihiro Kanno, Taeko Izumi, Akira Kas ...
    1983 Volume 56 Issue 7 Pages 2023-2028
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    syn- and anti-[0]Orthocyclo[2]orthocyclo[0](1,1′)ferrocenophan-7-enes were synthesized via an intramolecular reductive coupling of 1,1′-bis(o-formylphenyl)ferrocene with low valent titanium reagents, syn- and anti-[0]Orthocyclo[2]orthocyclo[0](1,1′)ferrocenophanes and [0]paracyclo[2]paracyclo[0](1,1′)ferrocenophane were prepared by the reaction of 1,1′-bis[o-(bromomethyl)phenyl]ferrocene and 1,1′-bis[p-(bromomethyl)phenyl]ferrocene with butyllithium. The transannular π-electronic interactions between two aromatic rings in these compounds were examined on the basis of the NMR and electronic spectra.
  • Seijiro Matsubara, Kazuhiko Takai, Hitosi Nozaki
    1983 Volume 56 Issue 7 Pages 2029-2032
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Treatment of ketones with bis(trimethylsilyl) peroxide and Lewis acid such as SnCl4 or BF3·OEt2 in dichloromcthane at room temperature affords esters in fair to excellent yields. Jasmine lactone is synthesized from 2-[(Z)-2-pentenyl]cyclopentanone by means of Me3SiOOSiMe3–BF3·OEt2 system without any protection of the carbon-carbon double bond. The oxidation of enol acetates of ketones to α-hydroxy (or α-acetoxy) ketones with Me3SiOOSiMe3–FeCl3 system is also disclosed.
  • Mitsuaki Ohmori, Yuji Tsujimoto, Masanosuke Takagi
    1983 Volume 56 Issue 7 Pages 2033-2036
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Three polarographic reduction waves, which appear when dehydro-L-ascorbic acid (DAA) is treated with o-phenylenediamine (OPD) in acetate buffer, pH 3.6, were renivestigated by comparing with those of the synthesized products from DAA and OPD. A reaction scheme of DAA with OPD is presented and the characteristics of the reactions are discussed.
  • Hisashi Matsumura, Toshio Tsuchiya, Tsuneko Takeda, Kimiaki Imafuku
    1983 Volume 56 Issue 7 Pages 2037-2043
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    3-Acetylbiphenyl-4-ol and -2-ol were condensed with substituted benzaldehydes to give respectively 5′-and 3′-phenyl-substituted chalcones (1ak), which were cyclized to afford 6- and 8-phenylflavanones. The chalcones (1ak) also gave the corresponding 6- and 8-phenylflavones via dibromides. The effects of the phenyl group on the spectral data are also discussed.
  • Tateaki Wakamiya, Kuniaki Shimbo, Akihiko Sano, Koichi Fukase, Tetsuo ...
    1983 Volume 56 Issue 7 Pages 2044-2049
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Synthesis of the ring A, a cyclic sulfide peptide part containing dehydroalanine residue, in peptide antibiotic nisin was successfully achieved by applications of two novel procedures. First, a sulfide ring was derived from a cyclic disulfide peptide by desulfurization with P(Et2N)3. Secondly, for the preparation of dehydroalanyl residue, a simple and convenient method through Hofmann degradation of 2,3-diaminopropionyl residue was newly exploited in the presence of sulfide linkage.
  • Hajime Takahashi, Masaaki Ito
    1983 Volume 56 Issue 7 Pages 2050-2054
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Oximation of dihydromayurone and 6,10,10-trimethyltricyclo[4.4.0.01,3]decan-4-one gives new isomeric oximes, respectively. The Beckman rearrangement of (Z)- or (E)-dihydromayurone oxime and (Z)- or (E)-6,10,10-trimethyltricyclo[4.4.0.01,3]decan-4-one oxime with polyphosphoric acid takes place prior to the Z-E equilibration of these isomers, respectively. Photolysis of the oximes gives two pairs of the isomeric lactams, 4-aza-8,12,12-trimethyltricyclo[6.4.0.01,3]dodecan-5-one, 5-aza-8,12,12-trimethyltricyclo[6.4.0.01,3]dodecan-4-one, 4-aza-7,11,11-trimethyltricyclo[5.4.0.01,3]undecan-5-one, and 5-aza-7,11,11-trimethyltricyclo[5.4.0.01,3]undecan-4-one. The reaction of either dihydromayurone or 6,10,10-trimethyltricyclo[4.4.0.01,3]decan-4-one with hydroxylamine-O-sulfonic acid in acetic acid affords only the lactam arising from the migration of the less substituted carbon.
  • Masahiro Nukui, Shohei Inoue, Yasukazu Ohkatsu
    1983 Volume 56 Issue 7 Pages 2055-2058
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Ethyl(N-methyltetraphenylporphinato)zinc (NMTPPZnEt 2) reacts with thiol (RSH: R=Prn, But, Ph) and hydrogen sulfide (H2S) to form N-methyltetraphenylporphinatozinc sulfide (NMTPPZnSR: R=Prn, But, Ph, H). Irradiation with visible light enhances the reactivity of 2 in the reaction with ButSH and brings about the homolytic cleavage of the zinc-sulfur bond of NMTPPZnSPrn in dichloromethane.
  • Shinji Kurokawa, Arthur G. Anderson, Jr.
    1983 Volume 56 Issue 7 Pages 2059-2064
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Azulene analogs of biological active amines were synthesized. Reaction of azulene or guaiazulene with 1-butanoylaziridine or with 1-butanoyl-2-methylaziridine in the presence of Lewis acid catalyst formed the corresponding N-butanoyl-1-(1-azulenyl)-, N-butanoyl-2-(1-azulenyl)-, and N-butanoyl-2-(1-guaiazulenyl) derivatives of ethanamine, or 1-propanamine, or of 2-propanamine, respectively (59). Reaction of guaiazulene with 2-methyl-, or 1,1-dimethylaziridinium, or with 1,1,2,2-tetramethylaziridinium ions gave the corresponding 1-(1-guaiazulenyl)- and 2-(1-guaiazulenyl) derivatives of ethanamine, or 1-propanamine, or of 2-propanamine. 2-(1-Azulenyl)- and 2-(4,6,8-trimethyl-1-azulenyl) derivatives of ethanamine were also obtained by the action of 1,1-diethylaziridinium ion on azulene or on 4,6,8-trimethylazulene. Compounds 5, 6, and 9 were active in vitro in the inhibition of prostaglandin 15-hydroxydehydrogenase and of cyclic AMP-phosphodiesterase.
  • Akira Hanaki, Hiroko Kamide
    1983 Volume 56 Issue 7 Pages 2065-2068
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Hydrogen peroxide is shown to be produced as an intermediate from oxygen in the copper-catalyzed autoxidation of cysteine. The amounts of cysteine oxidized and of hydrogen peroxide formed varied depending on the reaction conditions employed. The perpxide upon forming was spontaneously utilized for the oxidation of cysteine. As a result, the ratio of the concentration of hydrogen peroxide formed to cysteine oxidized is variable depending on the conditions. But, in dilute solutions, where the oxidation by the peroxide was slow, a stiochiometric relation of 2:1 was obtained between cysteine consumed and hydrogen peroxide produced. The rate of autoxidation is dependent on the concentration of oxygen dissolved. The double reciprocal plot of the rate against the concentration of oxygen gives a straight line, which indicates a possibility of the Michaelis-Menten type mechanism concerning the reoxidation or oxygenation of Cu(I) species.
  • Haruhisa Shirahama, Kiyoharu Hayano, Gurdial Singh Arora, Eiji Osawa, ...
    1983 Volume 56 Issue 7 Pages 2069-2072
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Humulene was oxidized by lead tetraacetate in benzene to give 2,5,9-humulatrien-7-ol acetate and 1,5,9-humulatriene-3,7-diol diacetates. Conformational analysis of 1,5,9-humulatriene-3,7-diols was performed by NMR spectroscopy and molecular mechanics calculations.
  • Otohiko Tsuge, Shuji Kanemasa, Shigeori Takenaka
    1983 Volume 56 Issue 7 Pages 2073-2076
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Such imidazolium methylides as imidazolium dicyanomethylide and bis(ethoxycarbonyl)methlide react with the methylenecyclopropenes with unsaturated substituents at the 4-position in the fashion of double cycloaddition reaction, leading to the novel cage compounds, which involves an intermorecular 1,3-dipolar cycloaddition reaction and an intramolecular Diels-Alder reaction.
  • Seiichiro Ogawa, Takao Hattori, Tatsushi Toyokuni, Tetsuo Suami
    1983 Volume 56 Issue 7 Pages 2077-2081
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Some racemic (hydroxymethyl)cyclohexenepolyols and their derivatives of biological interest have been synthesized from DL-1,2,3-tri-O-acetyl-(1/2,3)-4-methylene-5-cyclohexene-1,2,3-triol derived from the corresponding dibromide by treatment with sodium acetate in hexamethylphosphoric triamide.
  • Gaku Yamamoto, Michinori Oki
    1983 Volume 56 Issue 7 Pages 2082-2085
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    9-Isopropyltriptycene derivatives carrying a fluoro, chloro, bromo, or t-butyl substituent in a peri-position were synthesized and their dynamic NMR behavior was studied to see the dependence of the barrier to rotation of the bridgehead substituent upon the bulkiness of the peri-substituent. The data obtained in this work together with those reported earlier disclose that, among the derivatives in which the peri-substituent is not buttressed by the 2-substituent, the peri-methoxy compound has the highest barrier and the barrier decreases as the bulkiness of the peri-substituent increases. 1,2,3,4-Tetrachloro and tetrabromo derivatives show the slightly positive buttressing effect.
  • Masatoshi Chikazawa, Masatoshi Amada, Takafumi Kanazawa
    1983 Volume 56 Issue 7 Pages 2086-2089
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The adsorbed amounts of chloro-substituted methanes, such as CH2Cl2, CHCl3, and CCl4, for KCl particles were measured by a volumetric method at various temperatures, and the isosteric heats of adsorption and differential entropies of the adsorbed molecules were estimated from the adsorption isotherms. The order of magnitude of the heats of adsorption at a coverage of θ=0.5 was found to be CH2Cl2>CHCl3>CCl4. Moreover, a plot of the dipole moments of the three adsorbates vs. the adsorption heat values gave a straight line. Therefore, the differences among the adsorption heats of the three adsorbates is mainly caused by an orientation of their dissimilar dipoles to the surface. It may be concluded that the chloro-substituted methanes are adsorbed on surface anions of KCl powder.
  • Susumu Matsuzaki, Naoto Koga, Ichiro Moriyama, Koichi Toyoda
    1983 Volume 56 Issue 7 Pages 2090-2092
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    IR spectra of the mixture of tetrathiafulvalene (TTF) and iodine showed that the two components react with each other in the solid state. Spectral changes with an increase in iodine content were analyzed on the basis of the spectra of TTF and the cations, and it was found that TTF is oxidized by iodine up to the dication in the solid state in contrast to the reaction in solution.
  • Kazuhiko Ichikawa, Toshiyuki Matsumoto
    1983 Volume 56 Issue 7 Pages 2093-2100
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The heat capacities, Cp, of the alkali metal nitrates, MNO3 (M= Li, Na, K, Rb, and Cs), in the solid and liquid states have been measured between 50 and 450 °C by means of adiabatic calorimetry. We have measured with a fair degree of accuracy the Cp values for the MNO3 systems, because the existing data on NaNO3 and KNO3 above 250 °C are quite scanty. Some empirical rules, some of which may extend to other salts, have been obtained from the results on Cp for the five alkali nitrates in the solid and liquid states. For the molten MNO3, the heat capacities at a constant volume, CV, were obtained from the thermodynamical relationship between CV and Cp, using the experimental values of Cp; the CV values have been interpreted in terms of the interionic and intraionic portions.
  • Sadamu Takeda, Gen Soda, Hideaki Chihara
    1983 Volume 56 Issue 7 Pages 2101-2105
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Proton spin-lattice relaxation time T1 in the plastic phase of 2,2-dimethylpropane (neopentane) was measured at 10 MHz up to 170 MPa between 192.7 and 308.2 K. T1 near the melting point is determined by self-diffusion. The enthalpy and volume of activation of this motion suggest that self-diffusion occurs through a single vacancy mechanism. The correlation time of self-diffusion at the melting point (Tf) is (3.2±0.5)×10−7 s irrespective of external pressure. The diffusion rate is a function only of TfT, i.e. the law of corresponding states holds. The feature of activation properties of self-diffusion is strongly correlated with the melting phenomenon. The melting curve of the phase diagram was also determined and a possibility of existence of another plastic phase was found above 40 MPa.
  • Tetsuya Osaka, Yoshio Iwase, Hiroshi Kitayama, Toshihiro Ichino
    1983 Volume 56 Issue 7 Pages 2106-2111
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The Oxygen evolution reaction on cobalt borides and composite cobalt borides was investigated in a 6M KOH solution (1 M=1 mol dm−3) using the factor of the magnetic properties. In the system of cobalt borides (Co:B=3:1) prepared at various sintering temperatures, the boride having a higher saturation magnetization revealed a higher activity of the oxygen evolution reaction. In the system of composite cobalt borides which have various magnetic moments, μB, a clear correlation between the activity of the oxygen evolution reaction and the saturation magnetization (or magnetic moment, μB) was observed for several composite cobalt boride species (i.e., Co–Fe–B, Co–Ni–B, Co–Mn–B, and Co–B). Among the composite cobalt boride species, the cobalt iron boride (Co:Fe:B=1:2:1) sintered at 450 °C showed the highest activity of oxygen evolution reaction in a 6 M KOH solution. The conditions of oxide formation on Co–Fe–B(1:2:1) and on Co–B(3:1) in a 6 M KOH solution were compared with those on cobalt by means of voltammetry and chronopotentiometry. It was concluded that the ease and stability of oxide films in higher oxidation states are strongly correlated to the activity of the oxygen evolution reaction which occurs on more highly oxidized oxide films.
  • Noriaki Hirayama, Masaji Kasai, Kunikatsu Shirahata, Yuji Ohashi, Yosh ...
    1983 Volume 56 Issue 7 Pages 2112-2115
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The structure of the novel sugar, methyl D-tetronitroside [methyl 2,3,4,6-tetradeoxy-4-(methoxycarbonylamino)-3-C-methyl-3-nitro-D-xylo-hexopyranoside], was determined by X-ray analysis. This compound is a structural component of the antitumor antibiotics, tetrocarcins. The space group is P21 with a=11.782(3), b=10.271(2), c=11.636(3) Å, β=105.12(4)°, and Z=4. The structure was solved by direct methods, and least-squares refinement using 2503 reflexions gave the final R value of 0.079. Both the two independent molecules take a 4C1 chair conformation and they are connected together through two hydrogen bonds. Although the average C–C distance in the rings is 1.527 Å, the C(2)–C(3) distance is significantly long (average 1.546 Å) due to the steric hindrance by the nitro groups.
  • Hitoshi Ohtaki, Atsushi Funaki, Bernd M. Rode, Gilbert J. Reibnegger
    1983 Volume 56 Issue 7 Pages 2116-2121
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The molecular and liquid structures of formamide have been studied by means of X-ray diffraction. Relative stabilities of aggregates of formamide molecules have been calculated by using the ab initio LCGO-MO-SCF procedure and minimal basis sets. The atomic distances within a formamide molecule and the intermolecular N···O distance between the hydrogen–bonded molecules are determined by the X-ray diffraction experiment as follows: C=O: 1.24(1) Å, C–N: 1.33(1) Å, N···O (intramolecular): 2.25(2) Å, and N···O (intermolecular): 3.05(5) Å. The intermolecular (Remark: Graphics omitted.) bond angle (Θ) is about 120°. It is concluded from the X-ray diffraction experiment that liquid formamide mainly consists of the chain-like hydrogen–bonded structure of formamide molecules by combining through –NH2···O=CH– interactions. The conclusion is supported by the ab initio calculations. Formation of ring-dimers in the liquid formamide has not been confirmed by the X-ray diffraction study, although a possibility of the formation of the ring-dimer structure as another constituent of liquid formamide is suggested from the ab initio calculations.
  • Akifumi Yamada, Tadatsugu Yoshikuni
    1983 Volume 56 Issue 7 Pages 2122-2124
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The kinetic parameters of electrode reactions of several geometric isomers of singly charged cobalt(III) complexes have been determined by means of Tast polarography. The complexes studied are trans-[Co(NCS)(NO2)(en)2]Cl·H2O, cis-[Co(NCS)(NO2)(en)2]Cl·2H2O, trans-[Co(NO2)2(en)2]NO3, cis-[Co(NO2)2(en)2]NO3, trans-[Co(NO2)2(NH3)4]NO3·0.5H2O, cis-[Co(NO2)2(NH3)4]NO3, trans-[CoCl(NO2)(en)2]NO3, and cis-[CoCl(NO2)(en)2]NO3. These complexes showed two irreversible reduction waves; the first corresponds to CoIII→CoII, and the second, to CoII→Co0. The electrochemical kinetic parameters for the one-electron reduction wave were obtained in 0.1 and 1.0 M acetate buffer solutions. The half-wave potentials for the first wave of the complexes were more positive for the cis isomers than for the corresponding trans isomers. The cathodic rate constants at E=0 for the cis isomers were also larger than those for the corresponding trans isomers. A slight increase in the rate constant with the decrease in ionic strength was observed.
  • Yasuhiko Yukawa, Yoshie Inomata, Toshio Takeuchi
    1983 Volume 56 Issue 7 Pages 2125-2128
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    An X-ray diffraction study of the title complex has been carried out. The crystal is orthorhombic, with the space group P212121; Z=4, a=10.021(3), b=13.562(4), c=7.298(3) Å. Block-diagonal least-squares refinements have led to the final R value of 0.035. The structure is very similar to that of dichloro(4-hydroxy-L-proline)cadmium(II), which has a one-dimensional polymer bridged by chlorine atoms and a carboxyl group like an infinite folding screen. The thermal behavior is, however, different from that of dichloro(4-hydroxy-L-proline)cadmium(II). The difference is likely to be due to a difference of the crystal structure, whether it contains intermolecular hydrogen bonds or not.
  • Takanori Kato, Teisuke Murayama
    1983 Volume 56 Issue 7 Pages 2129-2132
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The complex formation between molybdate and Alizarin Red S (ARS) has been studied by spectrophotometry and pH titration. Results by the former method confirm that the composition of the complexes formed corresponds to a ratio of 1:1 for molybdate to ARS and that the complexes are stable between pH 2 to 6. Those by the latter are summarized by the following stability constants at 25 °C and an ionic strength of 0.1: MoO42−+ars3−+2H+=MoO3ars3−+ H2O, log(β1⁄mol−3L3)=20.18±0.01; MoO42−+ars3−+3H+=MoO3(Hars)2−+H2O, log(β2⁄mol−4L4)=24.93±0.04 (the completely deprotonated species of ARS is denoted by ars3−, and the concentration of H2O is not included in the definition of stability constants). Protonation constants of MoO42− and ars3− were also determined under the same conditions.
  • Sang Yun Park, Koichi Aoki, Koichi Tokuda, Hiroaki Matsuda
    1983 Volume 56 Issue 7 Pages 2133-2137
    Published: 1983
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Double potential step chronoamperometry at the hanging mercury drop electrode is proposed for determination of diffusion coefficients of metals dissolved in mercury. The expression for chronoamperometric curves is obtained, from which the algorithm is derived for evaluating diffusion coefficients of metals. The diffusion coefficients of lead, zinc, and cadmium in mercury at 25 °C were determined by the present technique.
feedback
Top