Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 59 , Issue 1
Showing 1-50 articles out of 70 articles from the selected issue
  • Akira Kuboyama, Sanae Y. Matsuzaki
    1986 Volume 59 Issue 1 Pages 1-5
    Published: 1986
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    A complex formation between cyclodextrins (CD’s) and the two o-quinones (9,10-phenanthrenequinone (PHQ) and acenaphthenequinone (ANQ)) in a water–ethylene glycol 1 : 1 mixture glassy solution at 77 K was investigated using the nπ* phosphorescence spectra of these quinones. It was considered on the basis of the observed results that PHQ forms a 1 : 1 complex with γ-CD and ANQ a 2 : 1 complex with β-CD. The structures of these complexes are discussed. It was found that complexes between γ-CD and the PHQ– and ANQ– naphthalene charge-transfer complexes are also formed.
  • Shoichi Shimizu, Choichiro Hirai
    1986 Volume 59 Issue 1 Pages 7-11
    Published: 1986
    Released: June 27, 2006
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    The rates of the esterification of octanoic acid with 1-butanol catalyzed by macroreticular sulfonated ion-exchange resin were measured by the use of a batch reactor. The effects on the rate were investigated for variations in the amount of the catalyst, the temperature, and the reactant alcohol concentrations as well as those of water and butyl octanoate. From these data, it is considered that alcohol and water solvate the matrix-bound sulfo groups, and so this esterification system consists of a heterogeneous reaction catalyzed by un-ionized sulfo groups and a pseudo-homogeneous reaction catalyzed by solvated protons; in other words, catalysis by sulfonic acid resin is both heterogeneous and pseudo-homogeneous in liquid-phase esterification.
  • Kazunori Maruyama, Michio Také, Nobuyuki Fujii, Yoshié T ...
    1986 Volume 59 Issue 1 Pages 13-17
    Published: 1986
    Released: June 27, 2006
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    Characteristics of absorption spectra of heated PVA film could be simulated as combinations of absorption spectra of free polyenes corresponding to the type –(CH=CH)n– (n=1–13). The change in concentrations of polyenes produced in PVA films was calculated by means of simulation. Each polyene –(CH=CH)n– was assumed to be produced by a first order reaction with rate constant kn with respect to the concentration of –(CH=CH)n−1–. kn values (n=1–13) at several temperatures were obtained. Arrhenius plots of kn from straight lines, giving activation energies 57–63 kJ mol−1 for the reaction catalyzed by H3PO4 and 94–100 kJ mol−1 for that by H2SO4. The activation entropies are negative in both cases.
  • Masayuki Nakagaki, Shoko Yokoyama
    1986 Volume 59 Issue 1 Pages 19-23
    Published: 1986
    Released: June 27, 2006
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    The base-catalyzed hydrolysis of acetylcholine chloride (Ach) in the presence of cationic and nonionic surfactants was investigated. The rate of hydrolysis of Ach was determined by following the disappearance of Ach spectrometrically. At a constant pH of 9.0, addition of dodecyltrimethylammonium chloride (DTAC) at concentrations below the critical micelle concentration results in a large decrease in the apparent rate constant for the hydrolysis of Ach, kapp. The plot of kapp against the concentration ratio of DTAC to Ach (CDTAC/[D]0) gives a break point at CDTAC/[D]0=1. This is considered to be due to the formation of 1 : 1 complex between Ach and DTAC. In the presence of heptaoxyethylene dodecyl ether (HED)–DTAC mixed micelles, kapp decreases with the mole fraction of DTAC, in contradistinction to the usually presupposed electrostatic effect. This is because Ach molecule penetrates into the micellar phase and is shielded from the attack by OH for hydrolysis. The decrease of kapp has been successfully interpreted on the basis of the data on the distribution of Ach between the micellar and aqueous phases.
  • Yoshiyuki Hirashima, Koji Kanetsuki, Ikuo Yonezu, Noriyuki Isobe, Jiro ...
    1986 Volume 59 Issue 1 Pages 25-29
    Published: 1986
    Released: June 27, 2006
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    The lanthanoid nitrate complexes of tri-, tetra-, and pentaethylene glycols (EO3, EO4, and EO5) exhibited anomalous stability trends attributed to structures similar to those of crown complexes. The stability constants of the EO4 and the EO5 complexes decreased with an increase in the atomic number of the lanthanoid in contrast to the lanthanoid complexes with most other ligands. A maximum stability was found at europium for EO3 complexes. The decomposition temperatures of EO3 complexes were higher than those of the corresponding EO4 and EO5 complexes. The yields of the solid complexes in reactions of the lanthanoids with EO5 decreased with an increase in the atomic number of the lanthanoid (with some exceptions). The separation factors observed for fractional precipitation using EO5 as the separating reagents were comparable to those reported regarding reagents practically used for lanthanoid separation.
  • Hiroshi Kawaguchi, Mizuki Matsuki, Tomoharu Ama, Takaji Yasui
    1986 Volume 59 Issue 1 Pages 31-38
    Published: 1986
    Released: June 27, 2006
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    All four possible optical isomers (Δ(S), Δ(R), Λ(S), and Λ(R)) of the bis(biguanide)sarcosinatocobalt(III) ion, [Co(sar)(Hbg)2]2+, were isolated and characterized by their absorption, CD, and 1H NMR spectra. The optically active [Co(sar)(Hbg)2]2+ ion in a basic aqueous solution showed a loss of CD intensity due to racemizations at both the chiral cobalt center (Δ\ ightleftarrowsΛ) and the asymmetric nitrogen center (R\ ightleftarrowsS). The rate of an R\ ightleftarrowsS change was ca. 50 times slower than that of a Δ\ ightleftarrowsΛ change. The rate of deuteration (H→D) at the asymmetric nitrogen atom was slower than those of other sarcosinato complexes. The ratio kH–D/kinv was about 102–103. The rates of racemization (Δ\ ightleftarrowsΛ) for the [Co(amino acidato)(Hbg)2]2+ ion series increased in the order L-valine<L-alanine<glycine<sarcosine.
  • Junko Motonaka, Hiroshi Nishioka, Sanae Ikeda, Nobuyuki Tanaka
    1986 Volume 59 Issue 1 Pages 39-42
    Published: 1986
    Released: June 27, 2006
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    For the measurement of manganese(II)-ion activity, manganese(II) ion-selective electrodes were prepared and tested. As electrodes, heterogeneous membranes were prepared by dispersing sensitive materials, such as manganese sulfide, manganese borate, or manganese dibenzyldithiocarbamate, in silicone rubber, poly(vinyl chloride), or poly(vinyl acetate). A manganese chloride solution (0.1 mol dm−3) was used as the internal reference solution, along with an Ag/AgCl internal reference electrode. The manganese(II) ion-selective electrodes thus made were then examined in terms of their response curves, response times, the effect of the pH, the variation in the response slopes with the temperature, and selectivity coefficients. The response time of the manganese dibenzyldithiocarbamate electrode was within 15 s in the concentration range of 10−8–10−1 mol dm−3. The response slope was 33.14 mV/pMn2+ in the linear part, and the coefficient of correlation was 0.999. The selectivity coefficients were examined by the separate-solution method.
  • Shuhei Fujinami, Hiroshi Miyamae, Takahiro Miura, Koichi Fushimi
    1986 Volume 59 Issue 1 Pages 43-47
    Published: 1986
    Released: June 27, 2006
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    An X-Ray analysis of all-cis(NO2,N,O)-(−)450CDK[Co(NO2)2(gly)2]·1/2H2O has been carried out. The crystal form is trigonal, P3121, with a=10.747(1), c=18.589(4) Å and Z=6. The structure was refined by a block-diagonal least-squares method to a final R value of 0.047 for 3207 independent reflections with |Fo|>3σ(|Fo|). The absolute configuration of the (−)450CD[Co(NO2)2(gly)2] ion has been determined to be Δ(R). By comparing the CD spectrum of Δ(R)-[Co(NO2)2(gly)2] with that of a related Λ(R)-[Co(NO2)2(en)(ox)] complex, the optical activities of these complexes have been concluded to be derived largely from helical distributions of chelate rings.
  • Y\={u} Komatsu, Yoshinori Fujiki, Takayoshi Sasaki
    1986 Volume 59 Issue 1 Pages 49-52
    Published: 1986
    Released: June 27, 2006
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    The distribution of cobalt(II) ions between crystalline hydrous titanium dioxide fibers and aqueous solutions has been investigated. The adsorption behavior of cobalt(II) ions is explained in terms of their ion exchange with hydrogen-ions in the fibers. The distribution coefficients of cobalt(II) ions, Kd, increased with increasing temperature at 298–373 K. Slopes of the plots of logKd vs. pH for 398–423 K were ca. +1.6, which was somewhat lower than those for 298–373 K: +2.0. X-Ray powder diffraction patterns indicate that the fibers hold a layer structure up to 373 K but change to anatase or its precursor above this temperature.
  • Takashi Hayashita, Makoto Takagi
    1986 Volume 59 Issue 1 Pages 53-57
    Published: 1986
    Released: June 27, 2006
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    The sorption and extraction of heavy metal thiocyanate complexes from an aqueous solution were studied for a cellulose acetate polymer and conventional organic solvents. The ease of metal sorption to solid cellulose acetate correlated well with the ease of metal extraction to liquid glycerol triacetate. The distribution behavior of ammonium thiocyanatozincate complexes was studied in detail and compared among cellulose acetate, isobutyl methyl ketone, and glycerol triacetate. The chemical processes involved in the metal distribution to the organic phase were found to be essentially the same for these three media. Thus, cellulose acetate was conveniently considered a polymer solvent. The results were discussed in relation to metalselective hyperfiltration through cellulose acetate membranes.
  • Hideyuki Tanaka, Takao Saito, Shinichi Motoki
    1986 Volume 59 Issue 1 Pages 59-66
    Published: 1986
    Released: June 27, 2006
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    5-t-Butyl-1,2-thiaphosphole 2-sulfides reacted with alcohols, thiols, and amines to give the 1,4-adducts, 2-alkoxy-, 2-(p-tolylthio)-, and 2-alkyl(aryl)amino-1,2-thiaphosphol-3-ene 2-sulfides, respectively. However, the reactions of 5-phenyl-1,2-thiaphosphole 2-sulfides with cyclohexyl- and arylamines afforded 1,2,3-dithiaphosphorins.
  • Toshiki Otake, Junko Tsukahara
    1986 Volume 59 Issue 1 Pages 67-71
    Published: 1986
    Released: June 27, 2006
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    A reaction of raffinose with an excess amount of 2,2-dimethoxypropane and p-toluenesulfonic acid as a catalyst in N,N′-dimethylformamide, followed by acetylation, gave seven kinds of mono-, di, or tri-O-isopropylideneraffinose peracetates with at least five kinds of minor products. A reaction of raffinose with a limited amount of 2,2-dimethoxypropane gave a new isopropylidene derivative with some of the derivatives described above. The isopropylidenation occurred at 1′,2-, 2,3-, 2″,3″-, 3,4-, 3″,4″-, and 4″,6″-positions. The structures of these compounds were established by 1H and 13C NMR analyses.
  • Fumihide Ishibashi, Takeo Nashima, Junko Nishino, Ikuko Kobayashi, Yos ...
    1986 Volume 59 Issue 1 Pages 73-76
    Published: 1986
    Released: June 27, 2006
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    Each geometrical isomer of various substituted phenylhydrazones of ethyl pyruvate and 2,4-dinitrophenylhydrazones of some α-keto esters was isolated in a pure state. Partial isomerizations of the E-isomers of the former hydrazones to the Z-isomers took place by keeping solutions of the hydrazones in organic solvents containing C, H, and Cl in the dark. An E- or Z-structure was assigned to each molecule on the basis of IR and 1H NMR spectra. In all cases, isomers with higher Rf-values on a silica gel TLC (using benzene as a developing solvent) involved an intramolecular hydrogen bonding between the imino hydrogen and the ester carbonyl oxygen. Thus, the Z-structure was assigned. An E-structure was assigned to other isomers with lower Rf-values. The present assignment is, thus, entirely the same as that proposed in a previous investigation.
  • Toshio Yoshioka, Masaharu Shimamura
    1986 Volume 59 Issue 1 Pages 77-81
    Published: 1986
    Released: June 27, 2006
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    Immobilization of microorganism cells by adsorption on a new polystyrene-based ion-exchange fiber has been studied. Microorganism cells, such as yeasts, bacteria, and actinomycetes, were well adsorbed on the anion-exchange fibers through an electrostatic force. The adsorption capacity for the cells became much greater as the water-holding capacity of the fibers increased. The adsorption and desorption behavior of the cells was different between actinomycetes and yeasts, and also between strong and weak anionexchange fibers. The enzyme activities of the immobilized actinomycetes containing glucose isomerase and yeasts containing L-aminolactam hydrolase were ca. 70 and 60% of those of the native cells respectively. The stability of the immobilized yeasts in the hydrolysis of DL-cyclic lysine anhydride was also investigated.
  • Tyo Sone, Ryoji Yokoyama, Yohko Okuyama, Kazuaki Sato
    1986 Volume 59 Issue 1 Pages 83-87
    Published: 1986
    Released: June 27, 2006
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    2-Chlorothiophene (1) was found to easily react with certain active aromatic compounds (2) in the presence of AlCl3 under mild conditions, yielding the corresponding 2-arylthiophenes (3) and 5-chloro-2,2′-bithienyl (5) as the main products. With compounds more reactive than 1, the formation of 3 predominated. Reactions of 1 with aryl alkyl ethers, for example, afforded the corresponding 3 in 44–83% yields in one step.
  • Hideyoshi Miyake, Kimiaki Yamamura
    1986 Volume 59 Issue 1 Pages 89-91
    Published: 1986
    Released: June 27, 2006
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    The nitro group, activated by a carbonyl group, alkoxycarbonyl group or a phenyl group, can be replaced by a phenylthio group in the reaction with benzenethiol or its potassium salt. This reaction proceeds in the electron transfer mechanism, and is applicable to the general syntheses of α-phenylthio ketones, α-phenylthio carboxylic esters and α-phenylthio alkylbenzenes from primary nitro compounds.
  • Shin-ichiro Takahashi, Ei-ichiro Suzuki, Yusuke Amino, Nobuya Nagashim ...
    1986 Volume 59 Issue 1 Pages 93-96
    Published: 1986
    Released: June 27, 2006
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    A crystal of inclusion compound of Aspartame (α-L-aspartyl-L-phenylalanine methyl ester, APM) with β-cyclodextrin (β-CD) was obtained from their aqueous solution. The Raman spectrum of this crystal indicates some differences from the spectral sum of APM and β-CD. An analysis of these spectral differences suggests that the phenyl moiety of APM is included in the cavity of β-CD in the inclusion compound. In addition, a Raman spectroscopic study of APM with 15N-substitution and N-deuteration indicates that the peptide backbone of APM undergoes some conformational change on APM going into the inclusion compound. Solid state 13C CP MAS- and gated-decoupling MAS–NMR spectra for the inclusion compound indicate that the phenyl ring rotates at a higher frequency than 270 MHz, that the Phe Cβ and phenyl ring Cl move at the frequency of about 270 MHz, and that the molecular motion of the other parts of APM occurs at lower frequency than 270 MHz.
  • Shoji Kajigaeshi, Toshiya Kadowaki, Akiko Nishida, Shizuo Fujisaki
    1986 Volume 59 Issue 1 Pages 97-103
    Published: 1986
    Released: June 27, 2006
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    Several 4-substituted 2,7-di-t-butylfluorene derivatives (3) were prepared by electrophilic substitutions of 2,7-di-t-butylfluorene (1). 4-Substituted fluorene (4), such as 4-bromo- (4a), 4-methyl (4e), and 4-acetylaminofluorene (4j), were obtained by the trans-t-butylations of 3. Although we attempted to synthesize 1,8-disubstituted fluorene from 3,6-di-t-butylfluorene (2) which was derived from 2,2′-diiodo-4,4′-di-t-butyldiphenylmethane (5), by the same methods, we obtained only 2,7-disubstituted fluorene derivatives (8); it turned out electrophilic substitutions of 2 gave 2,7-disubstituted 3,6-di-t-butylfluorene derivatives.
  • Shigekazu Kanemoto, Hiroki Tomioka, Koichiro Oshima, Hitosi Nozaki
    1986 Volume 59 Issue 1 Pages 105-108
    Published: 1986
    Released: June 27, 2006
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    Sodium bromate has been found to be effective oxidant for oxidation of alcohols in the presence of cerium or ruthenium compounds in biphase reaction. Selective oxidation of secondary alcohols was performed in the presence of primary ones using cerium(IV) ammonium nitrate (CAN) or cerium(IV) sulfate (CS) as catalyst. For instance, treatment of 1,10-undecanediol with CS/NaBrO3 provided 11-hydroxy-2-undecanone in 82% yield. Ruthenium catalyzed biphase oxidation of alcohols with sodium bromate provided the corresponding aldehydes or ketones in good to excellent yields.
  • Hidefumi Hirai, Susumu Hara, Makoto Komiyama
    1986 Volume 59 Issue 1 Pages 109-116
    Published: 1986
    Released: June 27, 2006
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    Carbon monoxide absorbents composed of linear polystyrene (PSt), aluminium halide, copper(I) halide, and toluene are prepared. The toluene solutions of polystyrene–protected aluminium copper(I) chloride (PSt–AlCuCl4) rapidly absorb CO at 20 °C under 1 atm (initial partial pressure of CO: 0.90 atm) and the equilibrium molar ratio of absorbed CO to the charged CuCl is 0.78. On the elevation of the temperature from 20 °C to 82 °C under 1 atm, the absorbed CO is released completely. The absorption-release cycles are repeated many times without measurable decrease in the absorbing capacity. The CO absorbing capacities of toluene solutions composed of aluminium halides, copper(I) halides, and polystyrene decrease as follows: AlCl3–CuCl system>AlBr3–CuBr system>>All3–CuI system=0. The CO absorbing activity of the toluene solution of PSt–AlCuCl4 remains virtually unchanged on the contact of the solution with nitrogen gas containing 10 mol% water to the charged CuCl (water content: 9000 ppm), when the molar ratio of phenyl residue of polystyrene (number-averaged degree of polymerization: 420, 50, or 4.0) to AlCuCl4 is unity or larger. This result is markedly in contrast with the fact that the activity of the toluene solution of AlCuCl4 without polystyrene significantly (25%) decreases on the contact.
  • Keiko Nishikawa, Takao Iijima
    1986 Volume 59 Issue 1 Pages 117-120
    Published: 1986
    Released: June 27, 2006
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    The concept of “reciprocal space expansion” has been applied in the analysis of the X-ray scattering intensity from liquid carbon tetrachloride. The results obtained by using the bcc local lattice structure model show very good agreement with the experimental intensity in the small-s region, where ghost peaks are inevitably introduced by the “real space expansion” usually adopted.
  • Michio Kimura
    1986 Volume 59 Issue 1 Pages 121-125
    Published: 1986
    Released: June 27, 2006
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    The crystal and molecular structure of 5-amino-2-phenyl-4-(9H-thioxanthen-9-yl)-1,2-dihydro-3H-pyrazol-3-one has been determined by the X-ray diffraction method to establish the predominant tautomeric form of the 3-pyrazolone ring in the solid state. The title compound, C22H17N3OS, crystallizes in the space group P21c with lattice parameters: a=18.179(4), b=8.333(1), c=11.961(7) Å, β=95.88(3)°, and Z=4. The 5-amino group is intramolecularly hydrogen-bonded to the sulfur atom of the thioxanthene ring (N–H···S=3.284 Å). In the packing structure, molecules are linked to each other through hydrogen bonds between the NH of amino and C=O groups [2.849 Å] and the NH moiety and C=O group [2.939 Å] of the 3-pyrazolone ring.
  • Peiji Wu, Takehiko Mori, Toshiaki Enoki, Kenichi Imaeda, Gunzi Saito, ...
    1986 Volume 59 Issue 1 Pages 127-132
    Published: 1986
    Released: June 27, 2006
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    The X-ray crystal structure analysis of a novel organic conductor (TTM-TTF)I2.47 (TTM-TTF: tetrakis(methylthio)tetrathiafulvalene) shows that the donors with an almost flat structure are stacked face-to-face to form columns. The iodine lattice composed of I3 columns is incommensurate with the donor lattice. The measurements of resistivity, thermoelectric power, and ESR show a metal-insulator transition around 100 K. This transition is attributed to the Peierls type phase transition. The quasi-one-dimensional electronic structure is supported by the arrangement of the donor molecules in the crystal and the calculated anisotropy of transfer integrals.
  • Ichiro Koiwa, Masao Nishikawa, Keizo Yamada, Tetsuya Osaka
    1986 Volume 59 Issue 1 Pages 133-137
    Published: 1986
    Released: June 27, 2006
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    The structure and the electric resistivity of electroless Ni–Mo–P alloy films, which were plated from a caustic alkali citrate-glycolic acid bath, have been investigated. The phosphorus content in deposits and the deposition rate decreased with increasing Mo-complex concentration which was formed with sodium gluconate before constructing the bath. The crystallized structure and the formation of solid solutions between the Ni matrix and the codeposited Mo were indicated by X-ray diffraction measurments for high Mo-complex concentration range. On the other hand, amorphous states appeared for the Mo-complex concentration range lower than 0.002 mol dm−3. In the range less than 0.002 mol dm−3 Mo-complex concentration, the resistivity of as-plated Ni–Mo–P films was higher than the binary Ni–P alloy film plated from the bath without the Mo-complex. In the higher Mo-complex concentration range, the resistivity immediately reached a constant value independently of the Mo-complex concentration. After 500 and 800 °C heat treatment under vacuum, the resistivity increased with increasing Mo-complex concentration. Moreover for the higher Mo-complex concentration range, the resistivity after heat treatment became higher than that of as-plated conditions, and the increased resistivity after the heat treatment depended on the Mo content in the deposits. Therefore, the codeposited Mo tended to increase the thermal stability of the films.
  • Kiyotaka Kojima, Tohru Inoue, Michiko Izaki, Ryosuke Shimozawa
    1986 Volume 59 Issue 1 Pages 139-144
    Published: 1986
    Released: June 27, 2006
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    Kinetic and equilibrium measurements were carried out for the complexation reaction of nickel(II) malonate and nickel(II) tartronate in an aqueous solution at 20 °C and at pressures up to 100 MPa. The reaction volume, ΔV0, and the activation volume, ΔVf*, for the complex formation were estimated from the pressure dependence of the stability constant and the rate constant. The results are as follows: ΔV0=13.5±1.0 cm3 mol−1 and ΔVf*=14.7±0.5 cm3 mol−1 for nickel(II) malonate, and ΔV0=13.3±0.7 cm3 mol−1 and ΔVf*=15.2±0.5 cm3 mol−1 for nickel(II) tartronate. The larger ΔV0 value compared with those obtained for dicarboxylate ligands which form a monodentate complex coincides with that malonate and tartronate form a chelate complex with nickel(II) in an aqueous solution. By appropriately estimating the volume changes associated with the outer-sphere complex formation and first-bond formation, the overall volume profile for the complexation reaction was obtained. A Similar feature regarding the volume profile for the complexation of nickel(II) malonate and nickel(II) tartronate suggests that tartronate forms a bidentate chelate complex by two carboxyl groups rather than by carboxyl and hydroxyl groups.
  • Chiaki Iwakura, Toshiyuki Edamoto, Hideo Tamura
    1986 Volume 59 Issue 1 Pages 145-148
    Published: 1986
    Released: June 27, 2006
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    The catalytic activity of a film-type bismuth ruthenate electrode for oxygen evolution was greatly enhanced by the electrochemical pretreatment, including potential holding and cycling. On the other hand, any appreciable enhancement in catalytic activity was not observed for a pellet-type bismuth ruthenate electrode. Such an pretreatment effect was explained on the basis of the participation of higher valence Ru species in the oxygen evolution reaction, rather than the increase of surface area.
  • Fumihiro Arifuku, Kikujiro Ujimoto, Hirondo Kurihara
    1986 Volume 59 Issue 1 Pages 149-154
    Published: 1986
    Released: June 27, 2006
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    The axial-ligand replacement of the [Tetrakis(1-methyl-4-pyridinio)porphine]iron(III) ion by the cyanide ion was investigated in a highly alkaline aqueous solution by means of the spectrophotometric method at 25 °C. In the course of the replacement, a protolytic equilibrium between monocyanomonoaqua- and monocyanomonohydroxo complex ions was observed; the p(Ka/mol dm−3 value of the monocyanomonoaqua complex ion was found to be 12.2±1.1. In the formation of the dicyano complex ion, the rate-determining step was the second replacement of axial ligands, i.e., from the monocyano complex ion to the dicyanocomplex ion; according as the pH is 11 or 13, the equilibrium constant was found to be 38.0 mol−1 dm3 or 11.0, while the rate constant was 1.07×10−3 or 4.23×10−3 mol−3 dm3 s−1.
  • Shoichi Ohta, Chikako Yoshimura, Naohide Matsumoto, Hisashi Okawa, Aki ...
    1986 Volume 59 Issue 1 Pages 155-159
    Published: 1986
    Released: June 27, 2006
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    Five binuclear iron(III) complexes bridged by pyrazine, 1,1′-tetramethylenebis(imidazol), or bis(pyridine) compounds with the formula of [LFe(Bge)FeL](BPh4)2 have been prepared, and their spin-equilibrium behavior between high-spin(S=5/2) and low-spin(S=1/2) states has been investigated by means of the temperature dependences of the magnetic susceptibilities and the electronic spectra, where Bge denotes pyrazine, 1,1′-tetramethylenebis(imidazol), 4,4′-bipyridine, 4,4′-ethylenebis(pyridine), or 4,4′-vinylenebis(pyridine), L=bis(3-salicylideneaminopropyl)amine, and BPh4=tetraphenylborate. The pyrazine complex is low-spin, while the bis(imidazole) and the bis(pyridine) complexes snowed a spin-equilibrium between high-spin and low-spin states, accompanied by a striking thermochromism in both the solids and solutions.
  • Shigenobu Funahashi, Naotaka Uchiyama, Motoharu Tanaka
    1986 Volume 59 Issue 1 Pages 161-167
    Published: 1986
    Released: June 27, 2006
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    The reaction of the iron(II) complex of 2,3,9,10-tetraphenyl-1,4,8,11-tetraaza-1,3,8,10-cyclotetradecatetraene ([FeL(CH3CN)2]2+, 1) with imidazole and thiocyanate ion in acetonitrile has been investigated spectrophotometrically at various temperatures and pressures. The axial substitution of 1 with imidazole is first order with respect to the concentration of the iron(II) complex and imidazole and the rate constant and the activation parameters are obtained as k (25.0 °C)=0.69 mol−1 kg s−1, ΔH\ eweq=76±4 kJ mol−1, ΔS\ eweq=7±13 J mol−1 K−1, ΔV\ eweq=13.7±0.9 cm3 mol−1. It has been demonstrated that at higher concentration of imidazole there exists self-associated imidazole which does not react directly with the complex. The axial substitution of 1 with thiocyanate ion proceeds through the ion-association between 1 and SCN prior to the rate-determining step from the outer-sphere complex to the inner-sphere complex. The activation parameters for the rate-determining step were determined as follows: k0 (25.0 °C and 0.1 MPa)=2.35 s−1, ΔH\ eweq=86±2 kJ mol−1, ΔS\ eweq=51±6 J mol−1 K−1, ΔV\ eweq=10.1±0.2 cm3 mol−1. The positive activation volumes strongly indicate a dissociative character of the activation process.
  • Yasushi Inoue, Hiromichi Yamazaki, Akira Osawa
    1986 Volume 59 Issue 1 Pages 169-174
    Published: 1986
    Released: June 27, 2006
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    The sodium isotopic exchange rate between the hydrous tin(IV) oxide ion exchanger in the Na+ form and aqueous solutions was determined radiochemically. When the dried exchanger was used, the rate of the first step was controlled by the rate of the equilibration of water in the exchanger with the solutions, while the second step was found to be controlled by the diffusion of sodium ions in the particles (particle diffusion). When the exchanger had been sufficiently immersed in solutions in advance, the particle diffusion controlled the rate from the beginning. From the dependency of the rate of particle diffusion on the apparent particle size and the specific surface area of the exchanger, and on the sodium-ion concentrations in the solutions, the process controlling the rate is considered to be the diffusion in the primary particles, which are formed at the initial stage of precipitation and which aggregate to form the hydrous tin(IV) oxide gel. The diffusion constants and their activation energy (35±2 KJ mol−1) were also evaluated.
  • Mitsuji Yamashita, Mineaki Kobayashi, Motoyuki Sugiura, Kenji Tsunekaw ...
    1986 Volume 59 Issue 1 Pages 175-178
    Published: 1986
    Released: June 27, 2006
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    Diphenylphosphinite derivatives of sugars were conveniently synthesized by the reaction of diphenylphosphinous chloride–triethylamine with sugar derivatives. Homogeneous asymmetric hydrogenations of several prochiral olefins, i.e., (Z)-α-acetylaminocinnamic acid, (Z)-α-benzoylaminocinnamic acid, itaconic acid, tiglic acid, and their esters, were carried out using rhodium(I) catalysts with the tervalent chiral phosphorus derivative of sugars. The highest optical yields for all the prochiral substrates investigated were obtained when di-μ-chloro-bis(cyclooctadiene)dirhodium(I) and methyl 2,3-O-isopropylidene-4-O-(diphenylphosphino)-α-L-rhamnopyranoside were used.
  • Kunikazu Sakai, Nobuko Hida, Kiyosi Kondo
    1986 Volume 59 Issue 1 Pages 179-183
    Published: 1986
    Released: June 27, 2006
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    Trichloroacetaldehyde tosylhydrazone acts as an excellent precursor of diazodithioacetate which is generated by treatment of the hydrazone with sulfide ion. This spontaneously cyclizes it to 5-mercapto-1,2,3-thiadiazole. The precursor also gives a 5-amino-1,2,3-triazole on reaction with an amine. α,α-Dichloro ketone tosylhydrazones similarly cyclize to give 1,2,3-thiadiazoles and 1,2,3-triazoles.
  • Shosuke Sofuku, Yasutaro Sugiyama, Ichiro Muramatsu
    1986 Volume 59 Issue 1 Pages 185-190
    Published: 1986
    Released: June 27, 2006
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    Gramicidin S (GS) analogs, [δAva3–4]–GS and [δAva3–4,3′–4′]–GS, were synthesized. Both of these peptides are analogs in which one or two L-leucyl-D-phenylalanyl residues of GS are replaced by one or two 5-aminovaleric acid residues. The CD spectrum of the mono-substituted analog has two troughs as that of GS. However, this analog showed almost no antimicrobial activity. Moreover, the di-substituted analog showed a CD spectrum that is ascribed to a random structure and had no antimicrobial activity.
  • Yasuo Kubo, Rie Toda, Kengo Yamane, Takeo Araki
    1986 Volume 59 Issue 1 Pages 191-199
    Published: 1986
    Released: June 27, 2006
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    Irradiation of benzene solutions of N-methyl-1,2-naphthalenedicarboximide (1) in the presence of alkenes (2a,b,di) gave two regio-isomers of naphthazepinediones (3a,b,di and 4a,b,di). Stereospecificity of the naphthazepinedione formation was observed in the reaction with cis- and trans-2-butene (2a and 2b). Naphthazepinediones (3j and 4j) produced by the irradiation of 1 with ethyl vinyl ether (2j) underwent secondary photoreactions to give 7 and 8, respectively. On the other hand, irradiation of 1 with 2,3-dimethyl-2-butene (2k) resulted in the formation of oxetanes (13a,b) and 1 : 1-adducts of 1 and 2k at the carbonyl groups of 1 (14 and 15a,b). Irradiation of 1 with cis-stilbene (2l) afforded oxetanes (22a,b) and fragmentation products of oxetanes (23a,b, and 24). Stern-Volmer slopes (kqτ) obtained from quenching of fluorescence of 1 by alkenes (2ae,k) correlated to some extent with relative rates for disappearance of 1 in the reaction. Preferential formation of the naphthazepinedione was rationalized by the nature of the excited singlet state of 1 compared with those of other N-methylarenedicarboximides.
  • Masayoshi Onishi, Katsuma Hiraki, Hatsumi Konda, Yasuhiro Ishida, Yush ...
    1986 Volume 59 Issue 1 Pages 201-206
    Published: 1986
    Released: June 27, 2006
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    Oxidative addition of (chloroformyl)ferrocene to [Pd(PPh3)4] yielded a stable acylpalladium(II) compound of [Pd(COFc)Cl(PPh3)2] (1), (Fc=ferrocenyl). Complex 1 was treated with alkali metal salts of poly(1-pyrazolyl)borates (HnBPz4−n), (Pz=1-pyrazolyl) to give complexes [Pd(COFc)(HnBPz4−n)(PPh3)], (2, n=0; 3, n=1; and 4, n=2), which retained the palladium-attached ferrocenylcarbonyl structure. Reaction of 1 with 1,10-phenanthroline (phen) afforded [Pd(COFc)Cl(phen)], whereas reaction with 2,2′-bipyridine gave [{Pd(COFc)Cl(PPh3)}2] as an isolable material. Transformation of the ferrocenylcarbonyl moiety took place to the ferrocenyl group on palladium, in chlorine-abstraction from 1 with AgClO4·H2O in CH3CN. In the temperature-dependent 1H-NMR spectra, fluxional behavior was observed for the poly(1-pyrazolyl)borate groups in 2 and 3. Electrochemical experiments were carried out for 14 in CH3CN using platinum working electrodes, and reversible one-electron redox-couples were detected, which were attributed to the process Fe(II)\ ightleftarrowsFe(III) in the ferrocenyl moiety. Furthermore, electron-withdrawing effects of the [poly(1-pyrazolyl)borato]palladiocarbonyl moieties from the Fe centers were compared among these complexes, in relation to their redox potentials.
  • Kazuhiro Nakasuji, Masakatsu Nakatsuka, Hideki Yamochi, Ichiro Murata, ...
    1986 Volume 59 Issue 1 Pages 207-214
    Published: 1986
    Released: June 27, 2006
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    Eight different 1:1 charge-transfer(CT) complexes were prepared using tetrahydrobarreleno-tetracyanoquinodimethane(THBTCNQ), dihydrobarreleno-tetracyanoquinodimethane(DHBTCNQ), monobenzobarreleno-tetracyanoquinodimethane(MBBTCNQ), and dibenzobarreleno-tetracyanoquinodimethane(DBBTCNQ) as tetracyanoquinodimethane(TCNQ)-type acceptors, and tetrathiafulvalene(TTF), bis(tetramethyene)-tetrathiafulvalene(OMTTF), and tetramethyl-tetrathiafulvalene(TMTTF) as TTF-type donors. The complexes can be classified into three distinct groups, I–III, on the basis of the magnitude of both the degree of CT and the electrical resistivity of compacted powders. Group-I complexes are characterized by a small band gap semiconductivity and moderate CT, group-II complexes by low conductivity and small CT, and group III complexes by low conductivity and complete CT. The stacking mode of the three groups of complexes are discussed, by comparing the electronic absorption spectra of the three groups of CT complexes with those of the complexes for which the crystal structures are known. A crystal structure analysis of OMTTF–DBBTCNQ revealed that it is the first example of a highly ionic CT complex of a TTF–TCNQ type with a regular mixed stacking mode. These three groups of complexes containing bulky acceptor groups will be of theoretical interest in studying the crystal properties of organic CT complexes.
  • Hideo Sawada, Masato Yoshida, Hidehiko Hagii, Kazuyoshi Aoshima, Michi ...
    1986 Volume 59 Issue 1 Pages 215-219
    Published: 1986
    Released: June 27, 2006
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    Bis(heptafluorobutyryl) peroxide (1) smoothly reacted with furans and thiophenes under mild conditions to regioselectively give 2-perfluoropropylfurans and thiophenes in high yields. Mechanistically, reactions with furans or thiophenes are considered to be initiated by one-electron transfers from substrates to 1. On the other hand, the perfluoropropylation of pyridine was proceeded by the usual free-radical substitution to a pyridinium salt by a heptafluoropropyl radical produced by the homolytic decomposition of 1.
  • Kiyohide Matsui, Akira Negishi, Yuriko Takahatake, Kikuo Sugimoto, Tam ...
    1986 Volume 59 Issue 1 Pages 221-227
    Published: 1986
    Released: June 27, 2006
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    A synthesis of the title compounds 5 involves the reaction between 3-methyl-2-buten-1-ol and triethyl orthoacetate to produce ethyl 3,3-dimethyl-4-pentenoate, which is followed by the addition of various carbon tetrahalides to the double bond. The reaction of resulting adducts with a base affords 5 in high yields. Stereoselective preparation of the cis-isomer was achieved by the following two methods: First one involves selective transformation of ethyl 4-bromo-6,6,6-trichloro-3,3-dimethylhexanoate to ethyl 6,6,6-trichloro-3,3-dimethyl-4-hexenoate (8a) with piperidine followed by the selective conversion of 8a to cis-2,2-dichloroethenyl compound (cis-5a). Second one is based on the stereoselective cyclization of ethyl 4,6,6,6-tetrachloro-3,3-dimethylhexanoate (t-BuONa/solvent/HMPA) to ethyl cis-2,2-dimethyl-3-(2,2,2-trichloroethyl)cyclopropanecarboxylate which is transformed into cis-5a without cis-trans isomerization.
  • Koji Araki, Shinsaku Shiraishi
    1986 Volume 59 Issue 1 Pages 229-234
    Published: 1986
    Released: June 27, 2006
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    D-Fructose is susceptible to photochemically-induced oxidation by atmospheric oxygen in the presence of a catalytic amount of iron or manganese cations in a neutral to weakly basic pH range. Metal hydroxide does not precipitate from a solution in this pH range because of the high sequestering ability of D-fructose. Upon irradiation of Pyrex-filtered light, D-fructose degraded into D-erythrose and other fragments. This reaction is shown to proceed by coupling with an oxidation-reduction cycle involving a metal cation, i.e., the photooxidation of D-fructose by M(III) and the subsequent reoxidation of the resultant M(II) by atmospheric oxygen.
  • Sotaro Miyano, Shigeru Handa, Masayuki Tobita, Harukichi Hashimoto
    1986 Volume 59 Issue 1 Pages 235-238
    Published: 1986
    Released: June 27, 2006
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    The copper-promoted Ullmann reaction of the title diester proceeded with high stereoselectivity to give 24-membered optically pure cyclic dimer of (S,S,S,S)-configuration as well as 12-membered monomeric cycle of (S,S)-configuration. The reaction also gave reduced, open-chain dimer enriched in (S,R,S)-diastereomer over (S,S,S)-counterpart (17% d.e.). Stereochemical course to the cyclic dimer was discussed considering the result that the intermolecular Ullmann coupling of chiral alcohol esters of 1-bromo-2-naphthoic acid poorly induced axial chirality in the joining of the two naphthyl units.
  • Yosuke Koizumi, Toshihiro Toyoda, Kunio Miki, Nobutami Kasai, Soichi M ...
    1986 Volume 59 Issue 1 Pages 239-242
    Published: 1986
    Released: June 27, 2006
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    The molecular structure of 12-bromo[2.2][2.2]paracyclophane has been determined by means of X-ray diffraction. The crystal is orthorhombic, space group Pbcn, a=12.768(1), b=11.515(1), c=13.074(1) Å, Z=4. The structure was solved by the heavy-atom method, and refined anisotropically by the block-diagonal leastsquares procedure; R=0.062. The Br–C···C–H axis of the central benzene ring lies on a crystallographic two-fold axis. The outer benzene rings take a boat form, and the central benzene ring is twisted.
  • Syoichi Makimoto, Keizo Suzuki, Yoshihiro Taniguchi
    1986 Volume 59 Issue 1 Pages 243-247
    Published: 1986
    Released: June 27, 2006
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    The pre-steady-state of the hydrolysis of p-nitrophenyl pivalate (pNPT) catalyzed by α-chymotrypsin (α-CHT) in Tris buffer solutions was measured up to 2.4 k bar at 25 °C. The reaction was initiated by substrate binding, and followed by acylation and deacylation processes. From the pressure dependence on the dissociation constants (Ks), the volume change ΔVKs was −14±1 cm3 mol−1. From the pressure dependence on the rate constants (kacyl and kdeacyl) of the acylation and deacylation processes, the activation volumes ΔVacyl\ eweq and ΔVdeacyl\ eweq were −24±1 and −2±1 cm3 mol−1, respectively. The reaction mechanisms of α-CHT are discussed in terms of the reaction and activation volumes.
  • Kazufumi Kato, Kunio Esumi, Kenjiro Meguro
    1986 Volume 59 Issue 1 Pages 249-253
    Published: 1986
    Released: June 27, 2006
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    The emulsion polymerization of styrene using a mixture of sodium dodecyl sulfate (SDS) and lithium fluorooctane sulfonate (LiFOS) has been studied. The polymerization rate decreased upon increasing the mole fraction of LiFOS, and was dependent on the solubilized amount of styrene in mixed surfactant solutions of SDS and LiFOS. The particle size increased upon increasing the mole fraction of LiFOS on the whole, and the molecular weight of the polymer formed in latices decreased upon increasing the mole fraction of LiFOS. Furthermore, the molecular-weight distribution of the latex polymer formed in mixed emulsifier solutions was considerably wider than that of the latex polymer formed in a single-emulsifier solution. It was confirmed from the above results that LiFOS had a repressive effect on the polymerization rate, and that it affected the number of particles and the molecular weight in the emulsion-polymerization process.
  • Keiichi Fukuyama, Hideo Fujita, Shigeru Tokushima, Tomitake Tsukihara, ...
    1986 Volume 59 Issue 1 Pages 255-258
    Published: 1986
    Released: June 27, 2006
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    The molecular structures of the adduct of fluoreno[9,1-bc]pyrylium-3-olate with methyl cinnamate (1), C25H18O4, and the dimerized product of fluoreno[9,1-bc]pyrylium-3-olate (2), C30H16O4, have been determined by the X-ray diffraction method. In the adduct (1), the phenyl ring is situated above the fluorene ring with a dihedral angle of 64°. The product 2 has a dimeric structure with a head-to-head type anti-configuration, and a local two-fold symmetry. Both crystals belong to a triclinic system with a space group P\bar1. The cell constants for 1 are a=13.287(4), b=8.794(3), c=8.797(3) Å, α=109.78(3), β=82.17(3), γ=88.58(3)°, and those for 2 are a=10.401(2), b=12.425(3), c=8.564(2) Å, α=103.77(4), β=108.76(4), γ=95.06(4)°. The structure of 1 was refined to R=0.067 for 2141 reflections, and that of 2 to R=0.058 for 2301 reflections.
  • Masakazu Anpo, Masaaki Yabuta, Sukeya Kodama, Yutaka Kubokawa
    1986 Volume 59 Issue 1 Pages 259-264
    Published: 1986
    Released: June 27, 2006
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    It has been found that UV irradiation of powdered TiO2 catalysts in the presence of butene molecules leads to both cis-trans and double bond shift isomerization reactions with high efficiency. In the photocatalytic isomerization the reactivity of 2-butene is much higher than that of 1-butene, being in contrast to the feature in the thermal isomerization. The addition of O2 or NO molecules leads to the complete inhibition of photocatalytic isomerization of butenes. The effect of adsorbed water on the photocatalytic isomerization has been investigated. From these results together with the ESR measurements under UV irradiation of TiO2 at 77 K in the presence of butene as well as O2 or NO, the following conclusion emerges: The interaction of the photo-formed O species or [Ti3+–O] pairs results in opening of the C=C bond of butene, i.e. formation of a radical species, which acts as the intermediate in the photocatalytic isomerization. The O as well as surface OH species participates in the hydrogen shift, i.e. the double bond shift isomerization. Thus, the reaction mechanism which has been proposed for the photocatalytic isomerization of butene over ZnO has been confirmed over TiO2.
  • Tomonori Konse, Kenji Kano, Tanekazu Kubota
    1986 Volume 59 Issue 1 Pages 265-270
    Published: 1986
    Released: June 27, 2006
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    Electrochemical equilibrium and kinetic parameters for a redox reaction caused by the hydroquinone moiety of adriamycin adsorbed on a pyrolytic graphite electrode have been determined by means of a numerical simulation of the quasi-reversible d.c. voltammograms using a theory regarding a two-step one-electron surfaceredox reaction, since the electron-transfer rate constant is so small that the reversible d.c. wave can not be obtained and an analysis by a.c. voltammetry is difficult. The voltammogram was also analyzed from the viewpoint of a one-step two-electron surface-redox reaction mechanism taking into account the interaction parameters between adsorbed molecules. The analyses in terms of both mechanisms mentioned above reveal that the redox system considered here occurs through a two-step process.
  • Hitoshi Ohtaki, Sumiko Itoh, Bernd M. Rode
    1986 Volume 59 Issue 1 Pages 271-276
    Published: 1986
    Released: June 27, 2006
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    The liquid structure of N-methylformamide (NMF) has been investigated by the X-ray diffraction method and the ab initio MO-SCF method. The structure parameters within a molecule were obtained as follows: C=O : 122(1) pm, C(methyl)–N : 145(2) pm, C(carbonyl)–N : 134(2) pm, N···O : 222(4) pm, C(methyl)···O : 278(6) pm. The intermolecular hydrogen–bonded N···O distance was estimated to be 298(11) pm. A linear and flexible chain structure was proposed for the liquid structure of NMF on the basis of scattered intensity data by the X-ray diffraction method and of interaction energies and geometries of hydrogen-bonded NMF molecules calculated by the ab initio MO calculations.
  • Masaaki Kojima, Kyoko Nakabayashi, Shigeru Ohba, Satoshi Okumoto, Yosh ...
    1986 Volume 59 Issue 1 Pages 277-283
    Published: 1986
    Released: June 27, 2006
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    The [Co(S-apS)(cyclen)]2+ (S-apS=(S)-1-amino-2-propanethiolate ion, cyclen=1,4,7,10-tetraazacyclododecane) complex was prepared and separated into two isomers (green and brown) by column chromatography. The crystal structure of the green isomer, [Co(S-apS)(cyclen)]ZnCl4·H2O was determined by X-ray analysis. Crystal data are as follows: monoclinic, space group P21, a=9.382(2), b=13.124(3), c=8.934(2) Å, β=91.08(3)°, and Z=2. The complex ion has a cis-octahedral geometry with the cyclen ligand coordinated in a folded, butterfly-like configuration and the bidentate S-apS ligand in a δ-gauche form. One of the two “planar” NH hydrogens of the macrocycle with respect to the S-apS ligand is directed opposite the S-apS chelate ring (exo), while the other “planar” and the remaining two “apical” NH hydrogens are directed to the S-apS ring (endo). The green isomer can be represented by endo(S,NH), where NH denotes the planar NH hydrogen cis to the sulfur atom. The other brown isomer was assigned as the exo(S,NH) configuration, where the S and NH2 coordination sites of S-apS in the green isomer are interchanged with each other, remaining the configuration of the macrocycle unchanged. Reversible isomerization between the two isomers occurred in aqueous solution and the kinetics was studied at 25.4 °C in the pH range of 5.98–6.97. The isomerization obeyed a rate law of the form, R=k[OH]·[complex], and was suggested to take place with synchronous inversion at the two nitrogen atoms of the macrocycle. The relative abundance of the two isomers at equilibrium is 1.0, and the forward and reverse second-order rate constants at 25.4 °C are 6.5×103 mol−1 dm3 s−1.
  • Masako Kato, Tasuku Ito
    1986 Volume 59 Issue 1 Pages 285-294
    Published: 1986
    Released: June 27, 2006
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    A new series of monomethyl carbonato complexes of nickel(II), cobalt(II), and copper(II) containing tetraazacycloalkanes (L) have been synthesized and characterized: Ni(L)(O2COCH3)(ClO4) (L=[14]aneN4 (1); L=[15]aneN4 (2); L=iso-[14]aneN4 (3); L=RSRS-Me4[14]aneN4 (4)), [Ni(RRSS-Me4[14]aneN4)(O2COCH3)2]·HNEt3ClO4 (5), Cu([14]aneN4)(O2COCH3)(ClO4) (6), [Cu(Me4[14]aneN4)(O2COCH3)](ClO4)·CH3OH (7), and Co(L)(O2COCH3)(ClO4) (L=[15]aneN4 (8); L=Me4[14]aneN4 (9)), where [14]aneN4=1,4,8,11-tetraazacyclotetradecane, [15]aneN4=1,4,8,12-tetraazacyclopentadecane, iso-[14]aneN4=1,4,7,11-tetraazacyclotetradecane, Me4[14]aneN4=1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane, RSRS-=1RS,4SR,8RS,11SR-, and RRSS-=1RS,4RS,8SR,11SR-. These compounds have been obtained through CO2 uptake reaction in basic methanol from the corresponding four-coordinate complex, [M(L)](ClO4)2. X-Ray structures of three compounds, 4, 5, and 6, have been determined. Compound 4 is a five-coordinate complex with the trigonal bipyramidal geometry (Type II), in which CH3OCO2 is coordinated in a unidentate fashion. Compound 5 is a tetragonally distorted sixcoordinate complex with two unidentate CH3OCO2 at axial sites (Type III). Compound 6 is also a tetragonally distorted six-coordinate complex but the CH3OCO2 ligand bridges two neighboring [Cu([14]aneN4)]2+ to form a linear chain structure (Type I). All the monomethyl carbonato complexes synthesized are classified into these three types on the basis of IR and/or electronic spectral data, supplemented with the X-ray results. Efficiency of the CO2 uptake depends strongly on the coordination structure which is controlled by a combination of metal ion and tetraazacycloalkane. Differences in reactivity among the complexes of various metal ions and factors influencing the efficiency have been discussed in connection with the zinc(II) system which undergoes the most effective CO2 uptake of this type.
  • Toshio Deguchi, Atsuya Higashi, Isao Sanemasa
    1986 Volume 59 Issue 1 Pages 295-300
    Published: 1986
    Released: June 27, 2006
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    Catalytic oxidations of ten organic dyes with an aromatic-hydroxyl or -amino functional group have been studied in the presence of metal ions such as cobalt(II), copper(II), and vanadium(V). Of these dyes, six were found to be effectively oxidized and decolorized specifically by one of these metals. 4,4′-Bis(3,4-dihydroxyphenylazo)stilbene-2,2′-disulfonic acid diammonium salt (Stilbazo) and 3,3′,4′-trihydroxyfuchsone-2″-sulfonic acid (Pyrocatechol Violet) were found to be promising for determining trace amounts of cobalt(II). The optimum analytical conditions have been studied for these two compounds with the aid of a flow injection analysis technique. The both reagents can be used to determine cobalt(II) down to 1 ppb.
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