Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 64 , Issue 10
Showing 1-50 articles out of 69 articles from the selected issue
  • Toshio Ogawa, Kiyoshi Mizutani, Yukimi Ando, Motoo Yasuda
    1991 Volume 64 Issue 10 Pages 2869-2871
    Published: 1991
    Released: June 07, 2006
    JOURNALS FREE ACCESS
    The apparent molal volumes (φv) at 25°C have been measured for the following urea derivatives in aqueous alkali chloride solutions (from density measurements) using a digital densimeter: urea, methylurea, ethylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1-diethylurea, and 1,3-diethylurea. The limiting values (φv°) were obtained by a linear extrapolation using the least-squares method. A notable feature of the transfer volumes found in this study was that hydrophobic urea derivatives, such as dimethylureas and diethylureas, had negative values for transfer from water to lithium chloride solutions. For the remainder, however, all transfer volumes were positive.
  • Shunzo Yamamoto, Satomi Inoue, Yoshimi Sueishi, Norio Nishimura
    1991 Volume 64 Issue 10 Pages 2872-2876
    Published: 1991
    Released: June 07, 2006
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    The mercury(63P1)-photosensitized decomposition of tetramethyltin (TMT) has been studied at 120 and 250°C and at pressures from 10 to 20000 Pa. The gaseous products detected were ethane, methane, and hydrogen. The yields of these products increased linearly with increasing reaction time and light intensity. From the effects of O2, NO, and H2 on the yield of ethane, the major primary reactions of the mercury-photosensitized decomposition of TMT were concluded to be processes with an Sn–C bond cleavage. The quantum yields of these products were independent of the TMT pressure at higher pressures than 200 Pa at 120°C. The quantum yield of ethane was also independent of the TMT pressure, while that of methane increased upon increasing the pressure at 250°C. The cadmium (53P1)-photosensitized decomposition of TMT has been studied at 280°C. The detected products were the same as those from the mercury-photosensitized decomposition, although the yield of hydrogen was very small. The pressure dependence of the yields of ethane and methane in the cadmium-photosensitized decomposition was very similar to those in the mercury-photosensitized decomposition of TMT at 250°C.
  • Tadashi Hata, Youji Furukawa, Toshiyuki Konosu, Sadao Oida
    1991 Volume 64 Issue 10 Pages 2877-2881
    Published: 1991
    Released: June 07, 2006
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    The title compounds were designed and synthesized as potential inhibitors of cytochrome P-450 14α-demethylase. The antifungal activity of (4R*,5R*)-isomer is markedly higher than that of (4S*,5R*)-isomer. The crystal structures of the two diastereoisomers were determined by X-ray diffraction technique. The final R indices of (4R*,5R*)- and (4S*,5R*)-isomers were 0.063 and 0.070 for 2840 and 2365 reflections, respectively. The different configuration at the 4-position in the oxazolidine ring causes the differences in the ring conformation and in some torsion angles. The three-dimensional structures of the two diastereoisomers are consequently different. Among the diastereoisomers and enantiomers, the (4R,5R)-enantiomer is superimposable on lanosterol, which is a substrate of cytochrome P-450 14α-demethylase, suggesting that the 4β-methyl group plays an important role in the antifungal activity.
  • Koji Abe, Hidetsugu Matsukiyo, Norihiro Ikeda, Makoto Aratono, Kinsi M ...
    1991 Volume 64 Issue 10 Pages 2882-2886
    Published: 1991
    Released: June 07, 2006
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    The surface tension of the aqueous solution of 2-(octylsulfinyl)ethanol (OSE) and decylammonium chloride (DeAC) mixture was measured as a function of total molality and composition of surfactants at 298.15 K under atmospheric pressure. The total surface density and compositions in the adsorbed film and micelle of the mixture were evaluated by applying thermodynamic relations to experimental results. It was found that the phase diagrams obtained for the adsorption and micelle formation of the mixture are different in shape from those of 2-(decylsulfinyl)ethanol (DeSE)–OSE and dodecylammonium chloride (DAC)–DeAC mixtures which are assumed to mix ideally in the adsorbed film and micelle. Such a nonideal behavior was attributed to the attractive interaction between OSE and DeAC molecules. Further, the interaction is concluded to be more attractive in the micelle than in the adsorbed film.
  • Masaya Mizunuma, Takeo Ohsaka, Hirohisa Miyamoto, Noboru Oyama
    1991 Volume 64 Issue 10 Pages 2887-2893
    Published: 1991
    Released: June 07, 2006
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    The in situ electrochemical quartz crystal microbalance (in situ EQCM) technique has been applied to study ion and solvent transport accompanying the redox reaction of polyvmylferrocene (PVF) film coated on quartz crystal electrodes in aqueous and acetonitrile media. The dependence of apparent formal potentials (Epolyf)app of the Fc°/Fc+ redox couple (Fc° and Fc+ represent the reduced and oxidized sites, respectively, in the PVF film) upon the concentration of supporting electrolyte has been also examined in comparison with those of solution-phase ferrocene derivatives. The PVF film is ideally permselective to ClO4 anion in both aqueous and acetonitrile media. The PVF oxidation (or reduction of polyvinylferricenium ion) in aqueous media is accompanied by the ingress (or egress) of one ClO4 ion per redox site and some solvent (ca. one H2O per redox site). In LiClO4 acetonitrile media, during the oxidation process ClO4 ion with some solvent inserts into the film and the reverse phenomenon occurs during the reduction process. The results demonstrate that a combination of the in situ EQCM measurement and the measurement of the dependence of (Epolyf)app on the concentration of supporting electrolyte makes possible to elucidate quantitatively the ion and/or solvent transport process across the polymer film/ solution interface during the redox reaction.
  • Toshihide Nishimura, Gerry G. Meisels, Yoshio Niwa
    1991 Volume 64 Issue 10 Pages 2894-2900
    Published: 1991
    Released: June 07, 2006
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    Dissociation of the fluorobenzene ion has been studied using threshold photoelectron–photoion coincidence (TPEPICO) mass spectrometry. The detailed breakdown curves were measured over internal energies from 0 to 9 eV. Asymmetric flight time distributions due to metastable dissociation were observed for the formations of C6H5+ and C4H3F+, and their absolute decay rate constants were derived from their flight time distributions. The information-theoretical approach has been employed for the analysis of kinetic energy release distribution (KERD). The results of surprisal analysis demonstrated that experimental KERDs are in good agreement with the predictions based on the statistical theory of mass spectra (QET). The heat of formation of C4H3F·+ has been estimated to be 222±2 kcal mol−1.
  • Takashi Ogura, Satoshi Takahashi, Kyoko Shinzawa-Itoh, Shinya Yoshikaw ...
    1991 Volume 64 Issue 10 Pages 2901-2907
    Published: 1991
    Released: June 07, 2006
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    The reduction of dioxygen by cytochrome oxidase has been investigated, in the time interval between 0.1 and 5.4 ms after initiation of the reaction, by using time-resolved resonance Raman spectroscopy combined with the Artificial Cardiovascular System [Ogura et al., Biochemistry, 28, 8022 (1989)]. At 0.5 ms we observed a new oxygen-isotope sensitive Raman band at 356 cm−1 for 16O2, which shifted down to 341 cm−1 for 18O2. The temporal behavior of this band was found to be very close to that of another oxygen-isotope sensitive band at 788 cm−1 which had been assigned previously to the Fe(IV)=O stretching mode of the ferryloxo intermediate [Ogura et al., J. Biol. Chem., 265, 14721(1990)]. However, the fact that the 788 cm−1 band shifts to a higher frequency (802 cm−1) in 2H2O, taken together with the present detection of two oxygen-isotope sensitive bands, prompts us to suggest an alternative assignment; namely, that these bands arise from the O–O (788 cm−1) and Fe(III)–O (356 cm−1) stretching modes of the Fe(III)–O–O–H intermediate. This conclusion forces a reconsideration of the currently accepted view of cytochrome oxidase catalysis.
  • Kazuhisa Moriyasu, Yasuharu Nishikawa
    1991 Volume 64 Issue 10 Pages 2908-2911
    Published: 1991
    Released: June 07, 2006
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    The geochemically interesting rare mineral, thortveitite, from Oro, Kyoto Prefecture was studied. Major constituents, scandium, yttrium, and lanthanoids, niobium, tantalum, aluminum, titanium, iron, calcium, and manganese were determined. The chemical analysis of the mineral assemblage gave Sc2O3 18.20, Y2O3 0.72, Σ Ln2O3 1.70, FeO 0.97, MnO 0.54, Nb2O5 trace, Ta2O5 9.96, Al2O3 3.02, CaO 1.72, TiO2 0.83, SiO2 58.31, and H2O 4.20; total 100.17%. This sample contained tantalite 11.47, anorthite 8.37, rutile 0.83, and quartz 37.91% in addition to thortveitite 37.40%. Scandium-tantalum substitution is suggested to occur similarly to yttrium-niobium substitution in earth acid minerals.
  • Hiroyuki Nariai, Itaru Motooka, Yukio Kanaji, Mitsutomo Tsuhako
    1991 Volume 64 Issue 10 Pages 2912-2917
    Published: 1991
    Released: June 07, 2006
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    The effect of water vapor on the thermal behavior of alkaline-earth metal cyclo-tetraphosphates, M2P4O12·nH2O (n=7.0, 3.5, 5.5, and 4.0 for M=Mg, Ca, Sr, and Ba, respectively) (P4m) was examined using DTA-TG, X-ray diffraction analysis, isothermal heating in an electric furnace, and HPLC-FIA. The calcination reaction of each P4m proceeded via ring opening of P4m with elimination of water of crystallization, followed by condensation of soluble oligophosphates (Poligo) to insoluble polyphosphates (Phigh poly). The rates of these reactions were faster for Mg2P4m than for other metal cyclo-phosphates. The decomposition of P4m was appreciably faster in humid air than in dry air, because of the availability of water for hydrolysis and for breaking the P–O–P linkage. However, the effect of water vapor from the atmosphere was not conspicuous, since the atmosphere contains enough water (theor. 20 mg L−1) for the hydrolysis of P4m. The products of calcination of Ba2P4m·4H2O were hardly influenced by water vapor from the atmosphere, because the water of crystallization was not easily released in the Ba system compared with the other metal salts.
  • Makoto Watanabe, Tomohiko Honda, Shinsaku Furuta
    1991 Volume 64 Issue 10 Pages 2918-2922
    Published: 1991
    Released: June 07, 2006
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    Lithium heptasodium cyclo-octaphosphate hexahydrate, LiNa7P8O24·6H2O, has been prepared by heating lead cyclo-tetraphosphate tetrahydrate at 340°C for 20 min, dissolving the thermal product in a 3% aqueous solution of tetrasodium ethylenediammetetraacetate, and then crystallizing by the addition of lithium chloride and methanol to the solution. When the cyclo-octaphosphate was heated above 180°C, it decomposed to produce phosphates with chain lenghts shorter and longer than that of the cyclo-octaphosphate. The thermally produced phosphates were reorganized to sodium cyclo-triphosphate and a small amount of insoluble polyphosphates by heating at about 300 to 350°C. The phosphates melted at about 620°C.
  • Masanobu Saeki, Mitsuko Onoda
    1991 Volume 64 Issue 10 Pages 2923-2925
    Published: 1991
    Released: June 07, 2006
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    A new barium niobium sulfide, Ba9Nb4S21, was prepared by the reaction of CS2 with a mixture of BaCO3 and Nb2O5. Powder X-ray diffraction peaks and electron diffraction spots for the compound were indexable on the basis of a hexagonal cell with lattice parameters of a=6.9743(6) and c=21.599(2) Å. Refinement based on powder X-ray diffraction data suggested that the crystal structure belongs to the same series with those of Ba16.5Nb9S42 and Ba2NbS5 reported by Swinnea et al.
  • Kazuo Eda, Noriyuki Sotani
    1991 Volume 64 Issue 10 Pages 2926-2930
    Published: 1991
    Released: June 07, 2006
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    Based on XRD and chemical analysis results, the hydrogen insertion compound of molybdenum oxide hydrate (H-hydrate) was suggested to be a genotypic compound of yellow molybdenum trioxide monohydrate, MoO3·H2O. H-hydrate was obtained in a hot HCl solution and in hot water from hydrogen molybdenum bronze, HxMoO3. The hydrogen bronze with x≤0.24 and the molybdenum species formed in the solution played a role in the formation of H-hydrate. In this process, a temporary dissolution of Mo5+ was observed at the beginning of the formation.
  • Yoshinori Araki, Akio Iwase, Setsuko Kudo, Toshishige M. Suzuki, Toshi ...
    1991 Volume 64 Issue 10 Pages 2931-2935
    Published: 1991
    Released: June 07, 2006
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    The structure and the homogeneous chemical equilibria of lithium β-diketonates (LiL), viz., Li(dbm), Li(bzac), and Li(acac), in dimethyl sulfoxide (DMSO) were studied by means of 13C NMR, IR spectral measurements, and rotating disk voltammetry, where dbm, bzac, and acac indicate the enolate anions of dibenzoylmethane, benzoylacetone, and acetylacetone, respectively. It was found by the 13C NMR and IR spectral measurements that LiL existed mainly as Li(uni-L) in DMSO, where uni- means that the ligand coordinates to the metal as unidentate. Since it is known that LiL dissociates slightly into ions in DMSO, LiL is involved in the following homogeneous chemical equilibrium:
    Li(uni-L)\ ightleftharpoonsL++L
    Furthermore, the apparent dissociation constant (logKapp) of LiL was obtained by rotating disk voltammetry in DMSO containing 0.1 mol dm−3 tetrabutylammonium perchlorate (TBAP), i.e., Li(dbm): −3.0±0.1, Li(bzac): −2.7±0.1, and Li(acac): −2.0±0.1, respectively. It was noted that the homogeneous chemical equilibria shifted more to the right in 0.1 mol dm−3 TBAP–DMSO than in DMSO alone. The behavior can be explained mainly in terms of the interaction between the π-electron system of Li(uni-L) and the cations of TBAP.
  • Hideaki Kanno, Junko Yamamoto, Satoshi Murahashi, Shunji Utsuno, Junno ...
    1991 Volume 64 Issue 10 Pages 2936-2941
    Published: 1991
    Released: June 07, 2006
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    A new chromium(III) complex, [Cr(4,4′-Me2bpdo)3]3+ (4,4′-Me2bpdo=4,4′-dimethyl-2,2′-bipyridine N,N′-dioxide) was prepared and resolved into a pair of enantiomers by an SP-Sephadex column chromatographic method using an achiral eluting agent Na2SO4. Both perchlorate and nitrate of the complex were found to crystallize in the lel2·ob(Δ(λλδ), Λ(δδλ)), form. Upon dissolution in water, the complexes isomerized to the lel3(Δ(λλλ), Λ(δδδ)), form with a rapid change in absorption spectra, and then racemized (Δ\ ightleftarrowsΛ) slowly. The rate constants at 35.0°C were 4.39×10−3 s−1 for the isomerization and 3.46×10−5 s−1 for the racemization. These inversion reactions including conformational change (δ\ ightleftarrowsλ) and configurational change (Δ\ ightleftarrowsΛ) are supposed to proceed by intramolecular mechanisms. The rates of isomerization and racemizatioin of the 4,4′-Me2bpdo complex are ca. two and ten times slower than those of [Cr(bpdo)3]3+ (bpdo=2,2′-bipyridine N,N′-dioxide), respectively.
  • Tetsuji Kitagawa, Masakazu Kita, Kazuo Kashiwabara, Junnosuke Fujita
    1991 Volume 64 Issue 10 Pages 2942-2947
    Published: 1991
    Released: June 07, 2006
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    Δ-RR,Λ-SS-[Co(acac)2(rac(P)-L]+ and [Co(acac)2(meso(P)-L)]+ were obtained by reaction of [Co(acac)3] (acac=2,4-pentanedionate ion) with 5,8-diphenyl-5,8-diphospha-2,11-dithiadodecane (L) in 1 : 1 molar ratio in dichloromethane in the presence of active charcoal, no Δ-SS,Λ-RR isomer of the rac(P)-L complex being formed. Five-coordinate [Ni(rac(P)-L)2]2+ and [Ni(meso(P)-L)2]2+ were yielded by reaction of Ni(II) and L in 1 : 2 molar ratio in methanol, and the molecular structure of less soluble [Ni(rac(P)-L)2](BF4)2 was determined by X-ray analysis. Crystal data: monoclinic, space group P21n, a=17.136(3), b=20.134(5), c=14.106(3) Å, β=93.30(2)°, V=4859(2) Å3, Z=4, R=0.089 for 8001 reflections. The Ni atom is surrounded square pyramidally by four P atoms in the basal plane and one S atom at the apical position with distances of the Ni–P: 2.214(2)–2.234(2) Å and the Ni–S: 2.603(2) Å. Both [Ni(rac(P)-L)2]2+ and [Ni(meso(P)-L)2]2+ in CH2Cl2 solutions exchange four –SCH3 groups at the apical positin on the NMR time scale. White [Cu(rac(P)-L)]BF4 was precipitated selectively by reaction of Cu(BF4)2·6H2O and L in 1 : 1 molar ratio in ethanol.
  • Koji Kato, Teruaki Mukaiyama
    1991 Volume 64 Issue 10 Pages 2948-2953
    Published: 1991
    Released: June 07, 2006
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    Various α,β-unsaturated carbonyl compounds, such as α,β-unsaturated esters, α,β-unsaturated ketones, α,β-unsaturated nitriles, and α,β-unsaturated amides, were directly converted to the corresponding a-hydroxyimino carbonyl compounds in high yields on treatment with butyl nitrite and phenylsilane in the presence of a catalytic amount of N,N′-bis(2-ethoxycarbonyl-3-oxobutylidene)ethylenediaminatocobalt(II) complex under mild conditions.
  • Yoshiaki Kusuyama, Takako Kubo, Masami Iyo, Tamami Kagosaku, Kenjiro T ...
    1991 Volume 64 Issue 10 Pages 2954-2960
    Published: 1991
    Released: June 07, 2006
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    The solvolysis rates of p-(cis- or trans-2-substituted cyclopropyl)-α-methylbenzyl chlorides including electron-donating and electron-attracting substituents relative to a hydrogen substituent were measured in 80% aqueous acetone. The trans isomers were more reactive than the corresponding cis derivatives where cyclopropyl and phenyl groups could not get a most favorable “bisected” conformation for the cyclopropyl group to release electrons to the benzene ring. The relative rates of the trans isomers at 45°C were best correlated by means of σm values with a ρ value of −3.14 and a correlation coefficient of 0.97, indicating that the cyclopropane ring was a poor transmitter of a resonance effect. The substituent effects were analyzed by means of the LSFE equation.
  • Masaki Matsui, Kenjiro Tsubota, Katsuyoshi Shibata, Hiroshige Muramats ...
    1991 Volume 64 Issue 10 Pages 2961-2964
    Published: 1991
    Released: June 07, 2006
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    The reactivities of dyes with ozone were in the following order, Acid Blue 74>disodium 1-(2-hydroxyphenylazo)-2-naphthol-3,6-disulfonate>Direct Yellow 12>Acid Orange 7>disodium 1-phenylazonaphthalene-3,6-disulfonate-2,2′-diolatocopper(II)>Mordant Red 3>Basic Green 4. The reaction of disodium 1-phenyl-azonaphthalene-3,6-disulfonate-2,2′-diolatocopper(II) with ozone was retarded by the introduction of electron-withdrawing groups and 8-sulfonato group. The potassium sulfonate dye was less reactive than the sodium one. Ozonization of l-phenylazonaphthalene-2,2′-diolatocopper(II) gave phenol, 2-naphthol, and phthalic anhydride.
  • Keiji Itoh, Saburo Nakanishi, Yoshio Otsuji
    1991 Volume 64 Issue 10 Pages 2965-2977
    Published: 1991
    Released: June 07, 2006
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    3-1- and 2-Trimethylsiloxyallyl)Fe(CO)2NO complexes were prepared by the reaction of the corresponding siloxyallylic halides with Bu4N[Fe(CO)3NO]. These complexes reacted with both of carbon nucleophiles and carbon electrophiles preferentially at the less hindered sites of the allylic ligands. In these reactions, (η3-1-trimethylsiloxyallyl)Fe(CO)2NO complexes served as synthetically equivalent synthons for both of β-acyl carbocations and j8-acyl carbanions and (η3-2-trimethylsiloxyallyl)Fe(CO)2NO complexes as both of α-acyl carbocations and α-acyl carbanions. The stereochemical courses of the reactions are described.
  • Naoki Sugimoto, Akiko Matsumura, Keiko Hasegawa, Muneo Sasaki
    1991 Volume 64 Issue 10 Pages 2978-2982
    Published: 1991
    Released: June 07, 2006
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    The effect of double-helix formations and unpaired terminal nucleotides of RNA oligomer substrates on a RNA ligation with T4 RNA ligase has been investigated by using high-performance liquid chromatography (HPLC), UV absorbance, and circular dichroism (CD) measurements, and the energy calculation for the double-helix stability of RNAs. In the 1-hour reaction of single-stranded RNA acceptors, the yield of the product increased in the order of pyrimidine donors pCp>pUp and purine donors pAp>pGp. In the reaction of a double-stranded RNA acceptor, UGCGCA, the yield also increased in the same order of the donors. On the other hand, in the reaction of double-stranded RNA acceptors containing unpaired terminal nucleotides (dangling ends), pUp and pGp donors gave the largest yields of the products in the reactions of AUGCGCA and CAUGCAU acceptors, respectively. Furthermore, the yield of the product is the largest for CAUGCAU acceptor within the acceptors having A, C, G, and U dangling ends in the reaction of pGp donor. These results sugggest that the formation of the terminal base pairs of the donors and the dangling ends may affect the RNA ligation with T4 RNA ligase.
  • Fuyuhiko Matsuda, Teruyo Matsumoto, Masako Ohsaki, Shiro Terashima
    1991 Volume 64 Issue 10 Pages 2983-2989
    Published: 1991
    Released: June 07, 2006
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    The title compound, (+)-14,14-difluoro-4-demethoxydaunorubicin hydrochloride (9), was prepared starting from the readily available (−)-hydroxy ester (10). This synthesis featured the efficient synthetic route to (−)-14,14-difluoro-4-demethoxy-7-deoxydaunomycinone (20) employing the Reformatsky reaction of ethyl bromodifluoroacetate with the (−)-siloxy aldehyde (14) and previously developed glycosylation method in which trimethylsilyl trifluoromethanesulfonate was used as an activator. In P388 in vitro test, 9 was found to be fifty times more active than adriamycin (1). Prominent antitumor activity was also observed for 9 in P388 in vivo test.
  • Shuji Kanemasa, Masahiro Kumegawa, Eiji Wada, Masafumi Nomura
    1991 Volume 64 Issue 10 Pages 2990-3004
    Published: 1991
    Released: June 07, 2006
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    The Michael addition of lithium 1,3-dien-2-olates with α,β-unsaturated carbonyl compounds is described. With α,β-unsaturated esters the reaction was reversible even at −78°C, while kinetically controlled with α,β-unsaturated ketones or alkylidenemalonates. At room temperature, the initially formed Michael adducts undergo subsequent intramolecular Michael addition to give substituted cyclohexanone derivatives in a highly stereoselective manner. Mostly anti-selectivity has been observed for the initial Michael addition, and the intramolecular cyclization was cis-selective.
  • Toshi Nagata
    1991 Volume 64 Issue 10 Pages 3005-3016
    Published: 1991
    Released: June 07, 2006
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    Synthesis of selectively metallated diporphyrins with electron-accepting moieties is described. Steady-state fluorescence spectra of these compounds snowed substantial quenching of the fluorescence of the free-base porphyrin. A possible “superexchange” mechanism of long-range electron transfer is discussed.
  • Sadayuki Mori, Shunji Tatsumi, Masaki Yasuda, Kiyoshi Kudo, Nobuyuki S ...
    1991 Volume 64 Issue 10 Pages 3017-3022
    Published: 1991
    Released: June 07, 2006
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    Cobalt-catalyzed hydroformylation of olefins was found to proceed even at ambient temperature under UV irradiation in the presence of phosphine. Extremely high selectivity toward straight-chain aldehyde (99% in case of 1-hexene) was obtained by lowering the partial pressure of carbon monoxide at ambient temperature. A catalytic species different from the well-known species under high pressure of carbon monoxide and high temperature contributed to the highly selective formation of straight-chain aldehydes. Two photochemical processes were suggested to be involved in the photochemical hydroformylation reaction, that is, the formation of HCo(CO)3PBu3 from the cationic cobalt species, [Co(CO)3(PBu3)2]+, and then the formation of the coordinatively unsaturated hydride, HCo(CO)2PBu3.
  • Haruo Nakayama, Masashi Yamanobe, Kei Baba
    1991 Volume 64 Issue 10 Pages 3023-3028
    Published: 1991
    Released: June 07, 2006
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    The solid-liquid phase diagrams of binary mixtures of water with tetraisopentylammonium alkanesulfonates, [(i-C5H11)4N][n-CnH2n+1SO3] (n=1–8), bis(tetrabutylammonium) alkanedisulfonates, [(n-C4H9)4N]2[O3S(CH2)nSO3](n=2–5), and with bis(tetraisopentylammonium) alkanedisulfonates, [(i-C5H11)4N]2[O3S(CH2)nSO3] (n=2–5), were examined in order to confirm the formation of hydrates. For all of the sulfonates examined the formation of hydrates has been newly confirmed. The hydrates of the tetraisopentylammonium alkanesulfonates have hydration numbers of around 37–40 and fairly high melting points (lie between 13 and 19°C). The typical hydrates formed by the bis(tetrabutylammonium) alkanedisulfonates have hydration numbers of around 52 and those by the bis(tetraisopentylammonium) alkanedisulfonates around 76. The former disulfonate hydrates have low melting points (between 1.0 and 10°C). However, the latter disulfonate hydrates have fairly high melting points (between 13 and 18°C). A salt with n=4 forms the most stable hydrate for both series of alkanedisulfonates. Judging from the hydration numbers and melting points, these hydrates seem to be clathrate-like.
  • Hiromu Satake, Takahiro Miyata, Shoji Kaneshina
    1991 Volume 64 Issue 10 Pages 3029-3034
    Published: 1991
    Released: June 07, 2006
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    Coated wire electrodes sensitive to procaine(PC), tetracaine(TC), lidocaine(LC), dibucaine(DC), mepivacaine(MC), and bupivacaine(BC), based on ion-pair formation between tetraphenylborate ions and the corresponding local anesthetic cations in a plasticized poly(vinyl chloride) membrane were prepared. The electrodes showed linear responses with Nernstian slopes (55–58 mV/decade) over concentration ranges of 4×10−5–10−2, 4×10−5–10−2, 10−4–10−−2, 4×10−5–10−2, 5×10−5–10−2, and 2×10−4–10−2 mol dm−3 for PC, TC, LC, DC, MC, and BC, respectively. The change in pH did not affect the electrode performance within ranges of 3.2–7.4, 3.2–7.4, 2.1–7.7, 2.5–7.4, 3.5–7.0, and 2.4–5.6 for PC, TC, LC, DC, MC, and BC, respectively. The reproducibility, stability, response time, and selectivity were also investigated. The electrodes were applied satisfactorily to the determination of local anesthetics by potentiometry.
  • Takehiro Abe
    1991 Volume 64 Issue 10 Pages 3035-3038
    Published: 1991
    Released: June 07, 2006
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    By considering the distance-dependent relative permittivity of a solvent, the Born equation has been modified for a diatomic ion in which the charge is located on an atom deviating from the center of a spherical cavity. The new equation has been successfully applied to the diatomic ions of OH, SH, and CN.
  • Masayoshi Onishi
    1991 Volume 64 Issue 10 Pages 3039-3045
    Published: 1991
    Released: June 07, 2006
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    Trichloro(nitrosyl)ruthenium(III) was treated with alkali-metal or thallium poly(1-pyrazolyl)borates M(BRPz3) (Pz=1-pyrazolyl) to give new nitrosyl[poly(1-pyrazolyl)borato]ruthenium(III) complexes [RuCl2(BRPz3)(NO)] (1, R=Pz; 2, R=H). A similar reaction with thallium tris(3,5-dimethyl-1-pyrazolyl)hydroborate TlBH(3,5-Me2Pz)3 (3,5-Me2Pz=3,5-dimethyl-1-pyrazolyl) afforded the complex [RuCl2{BH(3,5-Me2Pz)3}(NO)] (3) as the minor product and the 3,5-dimethylpyrazole complex [RuCl3(NO)(3,5-Me2PzH)2] as the major one. The observation of ν(NO) bands over the range 1870 to 1900 cm−1 determined the NO+ linear coordination mode in these complexes, rather than NO bent one. The ν(NO) values of 1–3 were larger than those of the corresponding known π-cyclopentadienyl analogues by ca. 90 cm−1, indicating a smaller degree of π-back donation of metal–NO bonds in the former complexes. 1H, 13C, and 1B NMR data of the new complexes are described. In 1H NOE measurements of 1, irradiation at a chemical shift of 5-H protons in the coordinated pyrazolyl groups induced a positive NOE on the 5-H proton in the uncoordinated group, and individual assignments of the pyrazolyl protons were carried out with the help of 1H–1H and 13C–H COSY.
  • Omar W. Steward, Michinobu Kato, Shih-Chi Chang, Martin Sax, Chong-Hwa ...
    1991 Volume 64 Issue 10 Pages 3046-3058
    Published: 1991
    Released: June 07, 2006
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    The synthesis and characterization of three copper(II) triphenylacetate-pyridine complexes are reported along with their magnetic and spectral properties: [Cu2(O2CCPh3)4(py)2]·C6H6 (1), [Cu2(O2CCPh3)4(py)2] (2), and Cu(O2CCPh3)2·2py (3). Crystal structure analyses of 1 and 3 have revealed unusual geometries around copper: 1, triclinic, space group P\bar1 with a=19.558(7) b=16.605(6), c=14.997(5) Å, α=14.55(2)°, β=97.11(2)°, γ=111.65(2)°, and Z=2; 3, monoclinic, space group P21c with a=8.931(1), b=12.602(1), c=19.578(1) Å, β=118.17(0.4)°, and Z=2. The coordination sphere around each copper in the dimeric complex 1 is a highly distorted trigonal bipyramid with bridging triphenylacetato ligands spanning the apical and equatorial positions, resulting in a long Cu–Cu distance of 3.086(1) Å. Temperature-dependent magntic susceptibility measurements on 1 indicate that the two coppers are antiferromagnetically coupled with −2J=187 cm−1. The structure of the monomeric complex 3 is unusual in that the out-of-plane carboxylate oxygen is twisted 12° from the normal. Two solid modifications are observed for 2. The magnetic and spectral properties of 2a (−2J=173 cm−1) resemble those of 1, and 2b (−2J=321 cm−1) those of copper(II) acetate monohydrate. Magneto-structural correlations are presented. The novel structural features of these complexes are suggested to arise from steric effects resulting from the spatial relationships both between and within the molecules in the crystal environment.
  • Yaou-Huei Huang, Chuh-Yung Chen, Jen-Feng Kuo
    1991 Volume 64 Issue 10 Pages 3059-3062
    Published: 1991
    Released: June 07, 2006
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    Liquid–liquid extraction of chromium(VI) from chromic acid solutions with triisooctylamine (tris(6-methylheptyl)amine, abbrev. to TIOA) dissolving in various organic solutions has been studied. The reaction between chromium(VI) and TIOA in o-xylene has been discussed in detail. It has been found that dichromate ion and hydrogen chromate ion coexist in the system, based on the extraction data and the IR and UV-visible spectra of the TIOA-chromium salt. The chromium extraction equilibria can be expressed as:
    ‾TIOA+H++HCrO4\ ightleftarrows‾(TIOAH)HCrO4
    2‾TIOA+2H++CR2O72\ ightleftarrows‾(TIOAH)2CR2O7
    The extraction constants are obtained.
  • Shayessteh Dadfarnia, Mojtaba Shamsipur
    1991 Volume 64 Issue 10 Pages 3063-3066
    Published: 1991
    Released: June 07, 2006
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    An extraction-spectrophotometric method for the determination of trace amounts of osmium(VIII) is described. Osmium is quantitatively extracted from aqueous solutions at pH 3.0–3.5 into a 10 : 1 chloroform–methyl isobutyl ketone mixture with tetrabutylammonium bromide, followed by spectrophotometric determination, using 4-(2-pyridylazo)resorcinol as a metallochromic indicator. The orange-red mixed complex of osmium absorbs light at λmax=530 nm with a molar absorptivity of 2.5×104 dm3 mol−1 cm−1. Beer’s law is obeyed over the range 0.5–18 μg cm−3. The method has a wide range and is sensitive and free from interferences from many anions and cations, including some platinum metals.
  • Hooshang Parham, Mojtaba Shamsipur
    1991 Volume 64 Issue 10 Pages 3067-3069
    Published: 1991
    Released: June 07, 2006
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    A simple, rapid, and sensitive kinetic method for the determination of trace selenium (0.03–1.5 μg cm−3) based on its catalytic effect on the reduction reaction of toluidine blue and sodium sulfide is reported. The reaction is monitored spectrophotometrically by measuring the decreasing absorbance of toluidine blue at 605 nm by the variable time method. The detection limit is 8 ng cm−3 and the relative standard deviation for 1 μg cm−3 selenium is 1.4%. The procedure was successfully applied to the determination of selenium in real samples.
  • Ratan L. Blokhra, Anil K. Sharma
    1991 Volume 64 Issue 10 Pages 3070-3074
    Published: 1991
    Released: June 07, 2006
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    Electromotive force measurements of the cell Cu–Hg/CuSO4(m)/Hg2SO4(s)/Hg have been made at 288, 298, 308, and 318 K for mannitol composition X=5, 15, and 25% (w/w) in water. The standard emf values of the cell at different temperatures and at different composition of mannitol + water mixtures have been determined by an extrapolation method. These have been utilized to evaluate the mean activity coefficient of copper(II) sulfate. The standard free energy for the cell reaction, and the primary medium effects upon CuSO4 have been evaluated. The standard thermodynamic quantities for the process of transfer of CuSO4 from water to the mannitol solution have been calculated from the values of the standard potential. The transfer parameters have been split into the electrostatic and chemical contributions and the results have been explained in the light of ion–solvent interactions and structural contributions to solvents.
  • Anoop Kumar Chhakkar, Lajpat Rai Kakkar
    1991 Volume 64 Issue 10 Pages 3075-3078
    Published: 1991
    Released: June 07, 2006
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    A highly sensitive and selective method for the determination of palladium in trace amounts is developed by complexation of Pd(II) with 2-(2-hydroxyimino-1-oxoethyl)thiophene (INAT) at pH 2.8–6.5, adjusted with diluted acetic acid. The colored species is quantitatively extracted into chloroform, whose absorbance is measured at 425 nm. The method is free from the interference of a large number of elements of great analytical importance. The usefulness of the method is further tested by analyzing different samples and the results obtained are quite satisfactory.
  • Yukihiko Inoue, Koji Araki, Shinsaku Shiraishi
    1991 Volume 64 Issue 10 Pages 3079-3083
    Published: 1991
    Released: June 07, 2006
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    The second-order rate constants of 1,3-dipolar cycloaddition reactions of 2,6-dichlorobenzonitrile N-oxide (1) with 2,5-dimethyl-p-benzoquinone (2a) or 2,6-diisopropyl-p-benzoquinone in various solvents at 20°C were determined by spectrophotometric method. The rate of 1 and 2a in ethanol : water=60 : 40 solution was 5.55×102 dm3 mol−1 s−1, which was fourteen folds of that in chloroform (3.9×10−3 dm3 mol−1 s−1). This solvent effect and the low solubility of the cycloadduct in aqueous ethanol were successfully applied to the cycloadduct synthesis.
  • Munehiro Nakatani, Tsunao Hase
    1991 Volume 64 Issue 10 Pages 3084-3088
    Published: 1991
    Released: June 07, 2006
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    A cyclopropene-ring-containing fatty acid ester, methyl (R)-2-hydroxysterculate, was isolated from Hibiscus rosa-sinensis along with methyl sterculate and malvalate. The stereochemistry of the asymmetric carbon at C-2 was determined as R by applying a dibenzoate chirality method, and a mild air oxidation afforded two conjugated enone isomers accompanying a ring opening.
  • Yasushi Kuroda, Atsutaka Kunai, Michiyuki Hamada, Tomoyuki Kitano, Sot ...
    1991 Volume 64 Issue 10 Pages 3089-3093
    Published: 1991
    Released: June 07, 2006
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    Catalytic oxidation of naphthalene in moist acetic acid solutions has been studied. The catalyst used was a silica-supported palladium which works in cooperation with the Cu+/Cu2+ redox couple. Products were 1-naphthol, 1,4-naphthoquinone and (E)-2-formylcinnamaldehyde with a total yield of more than 78% in which naphthoquinone shared 40%. Reaction mechanism has been discussed in comparison with that of benzene.
  • Yoshikiyo Moroi, Ryohei Matuura, Tadashi Yonemitsu
    1991 Volume 64 Issue 10 Pages 3094-3097
    Published: 1991
    Released: June 07, 2006
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    The proton NMR spectra of 1-tetradecanesulfonates whose cationic counterion, the 1,1′-polymethylenedipyridinium ion (with even-numbered methylene groups up to 14), is divalent with separate electric charge, were measured. From the chemical shifts the pyridine rings were found to move about in quite hydrophilic environment of micellar surface region, leading to a downfield shift of methylene groups next to head group of surfactant ion. The chemical shifts of methylene groups of micellized counterions with more than eight methylene groups are different from those of corresponding counterions in aqueous environment and are similar to those of methylene group in hydrophobic micellar interior. These results strongly support the previous conclusion that the polymethylene group with more than eight methylene groups folds and penetrates micellar interior in their micellized state.
  • Seishiro Fukutani, Nílson Kunioshi, Keizo Sakaguchi, Hiroshi Ji ...
    1991 Volume 64 Issue 10 Pages 3098-3104
    Published: 1991
    Released: June 07, 2006
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    Premixed stoichiometric flames of acetylene, ethylene, and ethane with air were investigated using a chemical scheme composed of eighty-two pairs of elementary reactions to illustrate the dependence of the propagation mechanisms of C2 hydrocarbon flames on the heat release distribution. The general role of heat release distribution through flames was depicted by means of an analytical treatment of the governing equations with the thermal properties of the gases being constant and the temperature profile given by an appropriate function of the position in the flame. It was found that the amount of heat released by chemical reactions at low-temperature regions of a flame is of fundamental importance for its propagation and that the main trigger of exothermic reactions at those zones is hydrogen atoms, which diffuses from the flame front; in the acetylene flame reactions consuming hydrogen atoms at the low-temperature region were found to yield all the heat released at that zone. Heat release distribution extended down to low-temperature regions was found to be able to lead to large burning velocities even though the amount of heat released at each position was small.
  • Yoshihiro Furukawa, Hirokazu Nagase, Ryuichi Ikeda, Daiyu Nakamura
    1991 Volume 64 Issue 10 Pages 3105-3108
    Published: 1991
    Released: June 07, 2006
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    Cationic self-diffusion in the ionic plastic phases of TlNO2 and TlNO3 was investigated by measuring temperature dependences of the 203,205Tl NMR spin-lattice relaxation time and the electrical conductivity. The NMR results snowed that the Tl+ ions in these phases undergo rapid translational diffusion with the activation energy (Ea) of 48 and 77 kJ mol−1 for nitrite and nitrate, respectively. The Ea values agreed well with those obtained from the electrical conductivity, indicating that the cation is the electric carrier. The diffusion constants (D) estimated from the relaxation time and conductivity data were ca. 10−12 m2 s−1 at the respective melting point (Tm) of plastic phase. The tendency that D at Tm has the characteristic value given above is recognized for other ionic plastic phases so far reported. The Tl+ ionic conductivity in TlSCN, which makes no plastic phase, was reported in comparison.
  • Biswanath Ghosh, Debranjan Ghosh, Archana Das Gupta, Nanda K. Das Gupt ...
    1991 Volume 64 Issue 10 Pages 3109-3114
    Published: 1991
    Released: June 07, 2006
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    Phenalenium systems have been studied using PPP method modified by Dewar et al. Ground state properties and other properties such as π*←π spectra, ionization potential, electron affinity, half-wave reduction potential, pi-dipole moment have been predicted and correlated with experimental ones where available. Stability and resonance energy have also been discussed.
  • Mohammad Ahmad, Hasan Arif, Haroon Rashid Khan, Mohammad Shoaib, Mohad ...
    1991 Volume 64 Issue 10 Pages 3115-3120
    Published: 1991
    Released: June 07, 2006
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    The fixed charge density, the permselectivity, and the transport number in several electrolytic solutions of varying concentration were determined across the pericardial membrane of freshly slaughtered buffalo (Bof. Bubalis). The irreversible thermodynamic equations originally meant for understanding the behavior of artificial membranes have been found to be equally applicable to those of the biological membranes.
  • Arun Kumar Srivastava, Kamla Kant Tewari, Isao Kojima
    1991 Volume 64 Issue 10 Pages 3121-3125
    Published: 1991
    Released: June 07, 2006
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    In the framework of CNDO (Complete Neglect of Differential Overlap method) VOIP (Valance Orbital Ionization Potential) has been evaluated using the method of Anno and Sakai and for exchange integrals Wolfsberg–Helmholtz approximation has been used. The method has been used for studying the disproportiontion of carbon monoxide on titanium and vanadium clusters having two atoms respectively. A large number of theoretical models were designed, based upon various mechanistic possibilities. The bond energies between different atoms have been plotted against the distance, for the purpose of studying the formation and desorption of CO2. The present studies suggest that the disproportionation of CO on titanium cluster may follow a dissociative path while in case of vanadium cluster this reaction may follow a disproportionation, where disproportionation involves a reaction between a ‘bridge site’ adsorbed CO molecule with a gas phase CO molecule.
  • Boon Hian Loo, Yue Guey Lee, Tamihiko Kato
    1991 Volume 64 Issue 10 Pages 3126-3128
    Published: 1991
    Released: June 07, 2006
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    Surface-enhanced Raman (SER) spectra have been obtained from N,N-dimethylthioacetamide (DMTA) adsorbed on Ag and Cu electrode surfaces. Vibrational analysis of the SER spectra of DMTA is made in comparison to the bulk-phase Raman spectrum of DMTA, and the infrared data on Co, Cu, and Hg complexes of DMTA. It is concluded that the DMTA molecule is bonded through its S atom to Ag and Cu surfaces.
  • Ashis Bhattacharjee, Biswanath Mallik
    1991 Volume 64 Issue 10 Pages 3129-3136
    Published: 1991
    Released: June 07, 2006
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    The effects of adsorption of different organic vapors on the electrical conductivity of some ferrocene derivatives have been studied using the sandwich cell technique. A conductivity peak is observed in the plot of measured current versus temperature for a sandwich cell of powdery material with some adsorbed vapors. The dependence of the intensity of the peak and the temperature at which it appears have been studied as a function of grain size of powdery materials, heating rate, amount of adsorbed vapor, and also the nature of the adsorbed vapors. At the vapor-adsorbed state these materials show very high value of activation energy and the pre exponential factor σo (in the usual semiconduction equation). Results indicate that the adsorption is a physical adsorption. The usual mechanisms for the adsorption-induced change in conductivity and activation energy are not suitable for explaining the observed results. Adsorption induced reversible structural phase transition seems responsible for the anomalous behavior of the adsorption-induced changes in the electrical properties of these materials. The results obtained with different ferrocene derivatives have been compared with that of ferrocene and possible reason for the adsorption induced phase transition is discussed.
  • Debabrata Goswami, Ranjit S. Sarpal, Sneh K. Dogra
    1991 Volume 64 Issue 10 Pages 3137-3141
    Published: 1991
    Released: June 07, 2006
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    Fluorescence quenching of few aromatic amines; aniline (AB), 1-naphthylamine (1-AN), 2-naphthylamine (2-AN), 2,3-naphthalenediamine (2,3-DAN), 9-phenanthrenamine (9-AP), 1-pyrenamine (1-APy), 2-chrysenamine (2-AC), 6-chrysenamine (6-AC), and 3-fluoranthenamine (3-AF) by dichloromethane, chloroform, and carbon tetrachloride has been studied in cyclohexane and acetonitrile. The quenching rate constants (kq) have been determined in both the solvents and these values are nearly independent of the solvent polarity. The values of kq are nearly equal to diffusion-controlled limits (kdiff) for CHCl3 and CCl4 in both the solvents, whereas for CH2Cl2 it is three to four order of magnitude less than kdiff. For a given amine, kq increases with the increase in electron affinity of the quencher, whereas for a given quencher (dichloromethane) kq increases with the increase in singlet state energy of fluorophore. The results obtained are explained in terms of a quenching mechanism involving an intermediate donor–acceptor (DA)* complex formed between the excited aromatic amine and quencher.
  • Joy Krishna Dey, Sneh K. Dogra
    1991 Volume 64 Issue 10 Pages 3142-3152
    Published: 1991
    Released: June 07, 2006
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    The absorption and fluorescence spectra of 2-(2-aminophenyl)-, 2-(3-aminophenyl)-, and 2-(4-aminophenyl)benzothiazoles (o-APBT, m-APBT, and p-APBT, respectively) have been studied in different solvents and at various acid/base concentrations. The ultraviolet and fluorescence spectra and the low pKa value for the monocation–neutral equilibrium have indicated the presence of an intramolecular hydrogen bond (IHB) in o-APBT in the S0 state. Excited state intra-molecular proton transfer (ESIPT) in o-APBT, gives rise to a non-fluorescent phototautomer. Large solvatochromic shifts in polar solvents have indicated the increase in the dipolemoment of m-APBT in S1 state. It has been observed that in protic solvents, m-APBT forms a complex with solvent molecule in the S1 state. The equilibrium constants for different prototropic equilibria of the molecules have been determined in both S0 and S1 states. The absorption and fluorescence spectra of the prototropic species have been explained and compared with those of 2-phenylbenzothiazole (2-PBT). The monocation (2) of p-APBT, formed by protonation at the –NH2 group is found to undergo structural reorganization leading to a quinonoid structure (2′). The absorption and fluorescence excitation spectra (recorded at 390 nm and 460 nm fluorescence bands) indicate the simultaneous presence of species (2) and (2′), the former being more favorable in protic and the latter in nonpolar solvents. The molecular orbital calculation (PPP) has been used to calculate the absorption spectra and the charge densities at the basic centers of the neutral molecules.
  • John Reji, P. Ravindran, N. R. Neelakantan, N. Subramanian
    1991 Volume 64 Issue 10 Pages 3153-3155
    Published: 1991
    Released: June 07, 2006
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    The viscosity values of Indian Space Research Organization’s (ISRO) hydroxyl terminated polybutadiene (HTPB) at various temperatures, the isothermal viscosity changes during the curing reaction of ISRO–HTPB with dlisocyanatotoluene (TDI) with and without catalyst and with a filler, calcium carbonate have been studied. The effect of temperature on this curing reaction is determined. The viscosity–time profile has shown an anomalous behavior and an explanation is put forward on the basis of polyurethane–HTPB, TDI mixture interaction. The viscosity–time profiles are drawn using normalized coordinates, which is helpful to compare the relative viscosity build up over relative periods.
  • Prabhat K. Das Gupta, S. P. Moulik, A. R. Das
    1991 Volume 64 Issue 10 Pages 3156-3159
    Published: 1991
    Released: June 07, 2006
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    Urea(U) can abstract H+ ion from p-nitrophenol (PNP) forming a hydrogen bonded ion pair (proton-transfer complex PNP ···H+U) of 1 : 1 stoichiometry with a formation constant 0.42 at 303 K. Infrared spectral measurements of the uronium phenolate and uronium nitrate have supported that the proton transferred from PNP is attached to the oxygen center of the amide. The needle shaped light yellow urea–PNP adduct is fairly stable under ordinary conditions decomposing at 398 K. The standard free energy, enthalpy, and entropy of formation determined from spectrophotometric and calorimetric methods have been found to be 3.62 kJ mol−1, −13.30 kJ mol−1, and −57.5 J mol−1 K−1, respectively at 303 K.
  • Atsushi Kawamoto, Masashi Tanaka, Jiro Tanaka
    1991 Volume 64 Issue 10 Pages 3160-3162
    Published: 1991
    Released: June 07, 2006
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    The crystal of (BEDT-TTF)4[Ni(CN)4] (BEDT-TTF: bis(ethylenedithio)tetrathiafulvalene) belongs to the triclinic P\bar1 with the lattice constants of a=10.994(2), b=16.443(2), c=9.703(1) Å, α=97.85(1), β=115.15(1), γ=95.94(1)°. In the crystal, there exists the face to face overlap of the BEDT-TTF molecules along the [201] direction. The intermolecular interaction by the short S···S contact is also observed along the [\bar201] direction.
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