Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 62 , Issue 12
Showing 1-50 articles out of 65 articles from the selected issue
  • Shinsaku Fujita
    1989 Volume 62 Issue 12 Pages 3771-3778
    Published: 1989
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    Cage-shaped hydrocarbons are enumerated, starting from the tetrahedron skeleton (Td symmetry). This enumeration stems from an edge strategy in which six edges of the skeleton are substituted by m methylene and n ethylene units. This is accomplished by a new method based on unit subduced cycle indices. This is a versatile methodology for counting cage-shaped hydrocarbons that have a given subsymmetry and an index term, xmyn, the latter of which corresponds to the molecular formula C4+m+2nH4+2m+4n.
  • Hideyuki Kuno, Kyoko Takahashi, Makoto Shibagaki, Hajime Matsushita
    1989 Volume 62 Issue 12 Pages 3779-3782
    Published: 1989
    Released: June 27, 2006
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    Platinum–alumina catalysts modified with carboxylic acid were prepared for the selective hydrogenation of unsaturated alcohols. These catalysts were stable in non-polar solvents. It has been demonstrated that the carbon–carbon double bond which is close to the hydroxyl group is preferentially hydrogenated in the case of several hexenols. This selectivity was applied to the regioselective hydrogenation of geraniol and citronellol was obtained in an 84.5% yield over one of the modified catalyst systems.
  • Kisaburo Umemoto
    1989 Volume 62 Issue 12 Pages 3783-3789
    Published: 1989
    Released: June 27, 2006
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    The electrochemical study clarified that ditetrazolium salts are reduced not only to the half-reduced “monoformazans” but also to the fully-reduced “diformazans” at the potential where the first electron is transferred to generate the “tetrazolinyl radical”. The key reaction leading to the simultaneous generation of mono- and diformazans was the disproportionation reaction of the tetrazolinyl radicals. The identification of absorption spectra of reaction intermediates was performed at several reaction stages.
  • Kim P. Simonsen, Nahomi Suzuki, Masatoshi Hamada, Masaaki Kojima, Shig ...
    1989 Volume 62 Issue 12 Pages 3790-3800
    Published: 1989
    Released: June 27, 2006
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    The fac-[Rh(edmp)3]3+ (edmp=(2-aminoethyl)dimethylphosphine), trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]+, and trans-[RhCl2(dmpe)2]+ (dmpe=1,2-bis(dimethylphosphino)ethane) complexes were prepared and the molecular structures were determined by the single crystal X-ray diffraction method. Crystal data and final R values are: fac-[Rh(edmp)3]Br3·3H2O, orthorhombic, Pna21, a=26.750(4), b=10.125(1), c=9.592(1) Å, V=2598.2(5) Å3, Z=4, R=0.039 for 1590 observed unique reflections. trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]PF6, monoclinic, P21/a, a=18.197(4), b=12.574(2), c=8.615(1) Å, β=96.59(2)°, V=1958.2(6) Å3, Z=4, R=0.032 for 3379 reflections. trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]ClO4, triclinic, P\bar1, a=13.122(2), b=17.952(2), c=12.343(2) Å, α=91.65(2), β=102.46(2), γ=80.74(1)°, V=2802.0(7) Å3, Z=6, R=0.070 for 7513 reflections, trans-[RhCl2(dmpe)2]CF3SO3, monoclinic, P21/a, a=13.166(2), b=24.337(4), c=8.002(2) Å, β=95.95(2)°, V=2550.1(8) Å3, Z=4, R=0.040 for 3201 reflections. It was found that the shorter the Rh–P bond length, the larger the trans Rh–N bond elongation. The mean Rh–P bond distance in trans-[RhCl2(dmpe)2]CF3SO3 (2.337(2) Å) is longer than those in fac-[Rh(edmp)3]Br3·3H2O (2.283(4) Å) and trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]PF6 (2.252(2) Å). A series of complexes of trans(X,X),cis(P,P)-[RhX2(edmp)2]+ (X=Cl, Br, I) and trans-[RhX2(dmpe)2]+ (X=Cl, Br) were also prepared and their absorption spectra were compared with one another and with those of the corresponding cobalt(III) complexes.
  • Mitsuo Abe, Masao Hirata, Masamichi Tsuji
    1989 Volume 62 Issue 12 Pages 3801-3807
    Published: 1989
    Released: June 27, 2006
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    The determination of selectivity coefficients for tervalent metal ions/hydrogen ions on cubic crystalline antimonic acid (C-SbA) was carried out for Ga3+, Fe3+, Ce3+, Sm3+, Y3+, Sc3+, and In3+ by batch equilibration at 30, 45, and 60 °C in nitric acid media. The selectivity in microamounts showed: Al3+<Tm3+<Ga3+<Yb3+=Y3+<Er3+<Dy3+<Fe3+<Eu3+<Sm3+<Ce3+<La3+<Sc3+=In3+. The ion-exchange isotherms of the systems of tervalent metal ions/hydrogen ions have also been studied on C-SbA. The selectivity coefficients in logarithm scale vs. equivalent fraction of metal ions in exchanger showed almost straight line, indicating monofunctional site with steric effect. In order to interpret the selectivity in microamounts of metal ions, hypothetical equilibrium constant was determined by extrapolating to zero loading of metal ions in C-SbA. From these values, the hypothetical thermodynamic data were calculated and evaluated.
  • Atsushi Takenaka, Hironobu Kobayashi, Katsumi Tsuchie, Itaru Motooka, ...
    1989 Volume 62 Issue 12 Pages 3808-3811
    Published: 1989
    Released: June 27, 2006
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    Ammonium copper(II) and ammonium calcium cyclo-hexaphosphates, Cu2(NH4)2P6O18·8.5H2O and Ca2(NH4)2P6O18·7H2O, were prepared by a wet method. TG-DTA, HPLC-FIA, and X-ray diffraction method were used to investigate the thermal decomposition of the cyclo-hexaphosphates. The effect of humidity on the pyrolysis was also examined by the use of dry N2 gas and humid air. Cu2(NH4)2P6O18·8.5H2O was mainly decomposed to oligophosphates by hydrolysis. Parts of the oligophosphates were changed to poly- (n=1–13) and highpolyphosphates through a condensation. The poly- and the highpolyphosphates were more abundant under the dried conditions. Above 280 °C ammonia was liberated. As the crystalline products, CU2P2O7 was identified at 380 °C, and CU2P4O12 above 430 °C. Ca2(NH4)2P6O18·7H2O lost almost all its water of crystallization by 177 °C. As ammonia was evolved from 270 to 420 °C, accelerated by humidity, amorphous highpolyphosphates were formed. The formation of the highpolyphosphates was considered to proceed through a radical polymerization, since oligophosphates were scarcely detected in the course of the thermal reaction.
  • Naohide Matsumoto, Hisashi Okawa, Sigeo Kida, Takanori Ogawa, Akira Oh ...
    1989 Volume 62 Issue 12 Pages 3812-3816
    Published: 1989
    Released: June 27, 2006
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    The synthesis, crystal structure, and magnetic property of an imidazolate-bridged manganese(III)–copper(II) dinuclear complex [Mn(salen)Cu(A)]BPh4 are described, where [H2salen]=N,N′-disalicylideneethylenediamine, [H2A]=4-(6-methyl-8-oxo-2,5-diazanonane-1,5,7-trienyl)imidazole, and BPh4=tetraphenylborate. The X-ray analysis confirmed an imidazolate-bridged manganese(III)–copper(II) dinuclear structure, in which the coordination geometries of the manganese(III) and copper(II) ions are square pyramid and square planar, respectively. The apical position of the manganese(III) ion is occupied by an imidazolate nitrogen N(3) of the [Cu(A)] moiety with the bond distance of Mn–N(3) 2.165(5) Å. As the temperature is lowered, the effective magnetic moment per molecule decreases gradually from 5.17 B.M. at 300.2 K, reaches the minimum value 4.44 B.M. at 24.9 K, and then increases to 4.73 B.M. at 4.2 K, indicating that antiferro- and ferro-magnetic interactions are co-operative in the complex.
  • Eiko Toyota, Yoshihisa Yamamoto
    1989 Volume 62 Issue 12 Pages 3817-3822
    Published: 1989
    Released: June 27, 2006
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    In a recent study, t- and p-salicylaldehydato[tris(2-aminoethyl)amine]cobalt(III) complexes, t- and p-[Co(salad)tren]Cl2·H2O, and cis1- and β2-RR,SS-salicylaldehydato(quadridentate amine)cobalt(III) complexes, cis1- and β2-RR,SS-[Co(salad)L]Cl2·nH2O (L: 2,3,2-tet; 3,2,3-tet), have been obtained from a reaction mixture of [CoCl2L]Cl·nH2O (L: tren; 2,3,2-tet; 3,2,3-tet), Ag2O, and salicylaldehyde. Two isomers were separated for each complex by SP-Sephadex C-25 column chromatography. The formation ratio of t- to p-isomers was ca. 1:3. The t- and p-configurations have been established by their absorption and 1H NMR spectra. On the other hand, the formation ratio of cis1 to β2-RR,SS-isomers was ca. 1:1 for both L=2,3,2-tet and 3,2,3-tet ligands. Their configurations have been established by their IR, absorption, and NMR spectra. The corresponding cis-α-isomer could not be obtained. Isomerization between t- and p-isomers or cis-β1- and β2-isomers was not observed in water at room temperature. The formation ratio and the absorption spectra of the complexes are different from those of the corresponding salicylato(quadridentate amine)cobalt(III) chloride hydrate, [Co(sal)L]Cl·nH2O (L: tren; 2,3,2-tet; 3,2,3-tet), previously reported. These differences have been attributed to a carbonyl bond between the carbonyl oxygen of the formyl group and a cobalt atom in the complexes.
  • Tasuku Akagi, Keiichiro Fuwa, Hiroki Haraguchi
    1989 Volume 62 Issue 12 Pages 3823-3827
    Published: 1989
    Released: June 27, 2006
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    The coprecipitation of trace metals with gallium has been investigated in detail especially with respects to the role of magnesium ion in saline or seawater. Gallium does not precipitate even at pH 9 when magnesium ion does not exist. The concentration of gallium in the precipitate increased with increasing that of magnesium in solution. The recoveries of trace metals also showed strong dependence on the concentrations of both gallium and magnesium in the aqueous solution.
  • Masaru Sato, Hirofumi Asano, Kaoru Suzuki, Motomi Katada, Sadatoshi Ak ...
    1989 Volume 62 Issue 12 Pages 3828-3834
    Published: 1989
    Released: June 27, 2006
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    1,7-Dithia-4-selena[7]- and 1,9-dithia-5-selena[9](1,1′)ferrocenophanes were prepared. These compounds, as well as 1,4,7-trithia[7]- and 1,5,9-trithia[9](1,1′)ferrocenophanes, were treated with (CH3CN)4Pd(BF4)2 or (CH3CN)4Pt(BF4)2 to give the corresponding 1/1 complexes in good yield. The spectral data of these complexes confirmed that there exsisted a dative Fe–Pd or Fe–Pt bond in these bimetallic complexes.
  • Takatoshi Hayashi, Yutaka Okada, Takeshi Inaba
    1989 Volume 62 Issue 12 Pages 3835-3837
    Published: 1989
    Released: June 27, 2006
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    The Claisen rearrangement of allyl o- or p-hydroxyphenyl ether is catalyzed by alkali metal salts. The mechanism of the catalytic effect is different from that by Lewis acids such as zinc chloride. It is considered that the hydroxyl group is dissociated into phenoxide ion –O with loss of its proton through attack by the anion residue of an alkali metal salt. Thus, the catalytic effect is attributable to a strong electron-releasing effect of phenoxide ion –O. Furthermore, for the o-isomer, an intramolecular repulsion between the phenoxide ion –O and the ethereal oxygen operates.
  • Minoru Tamura, Shozo Shiono, Kaoru Harada
    1989 Volume 62 Issue 12 Pages 3838-3844
    Published: 1989
    Released: June 27, 2006
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    Hydrogenolytic asymmetric transaminations between (R)-2-amino-2-phenylethanol and 2-keto acids were carried out over Pd catalyst in the absence or presence of various amount of sodium hydroxide in water or alcohols. The stereoselectivity of the reaction was significantly influenced by the amount of sodium hydroxide in the reaction mixture. When pyruvic acid was used in water the optical purity of alanine was 22% ee (R) and in 1 M (1 M=1 mol dm−3) sodium hydroxide solution it was 62% ee (S). When 2-oxobutyric acid was used in ethanol in the absence and presence of sodium hydroxide (1M), the optical yields of 2-aminobutyric acid were 2% ee (R) and 81% ee (S), respectively. In contrast, the addition of sodium hydroxide had little or no effect on the stereochemistry of the reaction using (S)-α-methylbenzylamine as a chiral source in aqueous or ethanolic solution. The substituent, additive, temperature, and solvent effects on the asymmetric reactions were examined in aqueous or ethanolic alkaline solution. Based on these experimental results, a possible explanation for the change in stereoselectivity by using sodium hydroxide is discussed.
  • Masayuki Fujii, Tetsuo Aida, Masakuni Yoshihara, Atsuyoshi Ohno
    1989 Volume 62 Issue 12 Pages 3845-3847
    Published: 1989
    Released: June 27, 2006
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    Imines are reduced into the corresponding amines in high yields by Hantzsch ester in the presence of silica gel. The reduction shows high chemoselectivity and stereoselectivity. Reduction of α,β-unsaturated imines proceeds with high regioselectivity to yield allylic amines (1,2-reduction products).
  • Shoji Wakabayashi, Takakazu Tanaka, Yukihiro Kubo, Junichi Uenishi, Sh ...
    1989 Volume 62 Issue 12 Pages 3848-3850
    Published: 1989
    Released: June 27, 2006
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    Cross-coupling product 2-(2-pyridyl)quinolines were obtained in the reaction of 2-(methylsulfinyl)quinolines and 2-(methylsulfinyl)pyridines with methylmagnesium bromide. Attempts of cross coupling in the reaction of other substrates were unsuccessful.
  • Toshiyuki Itoh, Tsuneyasu Fukuda, Tamotsu Fujisawa
    1989 Volume 62 Issue 12 Pages 3851-3855
    Published: 1989
    Released: June 27, 2006
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    The bakers’ yeast reduction of 2-alkyl-3-oxobutyronitrile gave optically pure 2-alkyl-3-hydroxybutyronitriles. Especially 2-phenyl-3-oxobutyronitrile gave only syn diastereomer of 2-phenyl-3-hydroxybutyronitrile in high optical yield.
  • Seiji Shinkai, Koji Araki, Tsutomu Matsuda, Osamu Manabe
    1989 Volume 62 Issue 12 Pages 3856-3862
    Published: 1989
    Released: June 27, 2006
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    The association constants (K) for aqueous complexes with water-soluble p-sulfonatocalix[n]arene (1n: n=4, 6, and 8) were determined by the NMR method. It was found that 14 and 16 form 1 : 1 complexes with guest molecules (trimethylanilinium chloride and 1-adamantyltrimethylammonium chloride), whereas 18 forms 1 : 2 18/guest complexes. The finding supports the view that calixarenes 1n’s are capable of molecular recognition on the basis of the ring size. Examination of the thermodynamic parameters for the association process established that the complexation with 14 is mainly due to the electrostatic force, whereas that with 16 and 18 is mainly due to the hydrophobic force. The coalescence temperatures (Tc’s) for calixarene ring inversion were subject to the template effect by these molecules. The activation parameters for the rate of ring inversion were estimated by a computer-assisted spectrum simulation: it was found that the Tc increase, observed in the presence of these guest molecules acting as templates, is caused by the increase in ΔH\ eweq. These findings provide new insights into the association characteristics of water-soluble calixarenes.
  • Masanobu Kojima, Hirochika Sakuragi, Katsumi Tokumaru
    1989 Volume 62 Issue 12 Pages 3863-3868
    Published: 1989
    Released: June 27, 2006
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    Irradiation of contact charge transfer (CCT) bands (320–370 nm) of 4-methoxystyrene (1a) and 4-methylstyrene (1b) with molecular oxygen in acetonitrile and benzene resulted in the formation of the corresponding cis- and trans-1,2-diarylcyclobutanes (2 and 3) as well as benzaldehydes (4), oxidative cleavage products. In the case of 1b, 7-methyl-1-(4-tolyl)-1,2,3,4-tetrahydronaphthalene (5) and 6-methyl-4-(4-tolyl)-1,2,3,4-tetrahydronaphthalen-1-one (6) were also afforded. The formation of these products is reasonably explained by electron transfer in the excited CCT pair followed by addition of the resulting 1 cation radical to ground-state 1 to form a dimer cation radical; its cyclization leads to the dimeric products and trapping of a cyclic dimer cation radical by oxygen affords ketone 6.
  • Hiroaki Ozaki, Shuhei Yamoto, Seiichirou Maikuma, Kenichi Honda, Takeo ...
    1989 Volume 62 Issue 12 Pages 3869-3876
    Published: 1989
    Released: June 27, 2006
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    Sequence-defined bis(deoxyribonucleoside) phosphoromorpholidate derivatives as stable intermediates to prepare oligodeoxyribonucleotides have been synthesized using morpholinodi(1-tetrazolyl)phosphine as a phosphitylating reagent. The general procedure is composed of following steps (in situ); a) a reaction of 5′-O-protected deoxyribonucleoside with morpholinodi(1-tetrazolyl)phosphine (phosphitylation), b) a reaction of the resulting 5′-O-protected deoxyribonucleoside phosphorobisamidite with the second deoxyribonucleoside (coupling), and c) a nonaqueous oxidation with t-BuOOH (oxidation). In the coupling step, the 5′-O-protected deoxyribonucleoside phosphorobisamidite was selectively reacted with 5′-OH group of the second deoxyribonucleoside, and therefore, a protection of hydroxyl groups of the second deoxyribonucleoside is not necessary. As the resulting P–N bond in the phosphoramidate linkage after oxidation is stable both in acidic and basic conditions, the morpholino function as a phosphoryl protecting group may have many potential use in the synthetic chemistry of oligonucleotide. A thymidine trimer can be obtained in a high yield by extending the present synthetic method.
  • Kazuhiro Maruyama, Yoshihiro Matano
    1989 Volume 62 Issue 12 Pages 3877-3885
    Published: 1989
    Released: June 27, 2006
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    Thermal reactions of acylquinones with allylstannanes in benzene afforded several kinds of product after column chromatography on silica gel; acyl allyl quinones, acyl allyl epoxy quinones, cyclopentanoid compounds including stannyl moiety, allyl hydroxy quinones, acyl hydroquinones, and acyl allyl hydroquinones. The main product comprises cyclopentanoid compounds, which are novel [2+3] cyclo adducts with 1,2-migration of trialkylstannyl moiety. Spectroscopic examinations (1H NMR and Vis-UV) enabled us to confirm the reaction pathways that four types of precursors were initially generated via polarized tight pair and inverted to isolated products during purification by column chromatography. Similar reactions in acetonitrile showed a remarkable difference in the reactivity, that is, acyl allyl quinones and the corresponding hydroquinones are obtained, but the [2+3] cyclo adducts are not produced at all. From 1H NMR examination, it was confirmed that three types of precursor are generated via solvent separated ion pairs at the initial stage. The rather strong reactivity of acylquinones towards allylstannanes will be due to electron withdrawing ability of acyl group.
  • Sotaro Miyano, Shin-ichi Okada, Hiroki Hotta, Masayuki Takeda, Takatsu ...
    1989 Volume 62 Issue 12 Pages 3886-3891
    Published: 1989
    Released: June 27, 2006
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    Axially chiral 2′-methoxy-1,1′-binaphthyl-2-carboxylic acid (1) was effectively utilized as chiral derivatizing agent for discrimination of enantiomeric alcohols and amines by 1H NMR with the aid of Eu(fod)3. Among a pair of the diastereomeric esters or amides prepared from (aS)-1 and an α-chiral alcohol or amine, the methoxyl protons of the (aS,R)-diastereomer showed the larger lanthanoid-induced downfield shift than those of the (aS,S)-counterpart. Thus, addition of up to 0.5–1.0 equiv amount of Eu(fod)3 caused base-line separation of those protons, allowing determination of the enantiomeric purities and assignment of the absolute configurations of the enantiomeric alcohols and amines. An X-ray crystallographic analysis of the amide ((aS,S)-2) obtained from (aS)-1 and (S)-1-phenylethylamine showed structural resemblance between the amides and esters of 1. Steric models which explain the NMR behavior of the diastereomeric esters and amides are presented based on X-ray analyses. Also reported are two methods to regenerate free acid 1 from amide 2 to afford axially homochiral 1.
  • Teiji Yanagi, Takayuki Oh-e, Norio Miyaura, Akira Suzuki
    1989 Volume 62 Issue 12 Pages 3892-3895
    Published: 1989
    Released: June 27, 2006
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    (2E,4E)-, (2Z,4E)-, and (2E,4Z)-2,4-Alkadienoates can be synthesized in high yields by the cross-coupling of ethyl (E)-3-bromoacrylate, methyl (E)-3-bromo-2-methylpropenoate, ethyl (Z)-3-bromocrotonate,1-bromo-2-(ethoxycarbonyl)cyclohexene, and 4-bromocoumarin with 2-[(E)-1-alkenyl]-1,3,2-benzodioxaboroles or diisopropyl (Z)-1-hexenylboronate in the presence of 3 mol% of Pd(OAc)2, 6 mol% of PPh3, and 2 equivalents of Na2CO3 or K2CO3 in alcoholic solvents while retaining the original configuration of the double bonds in β-bromo esters and 1-alkenylboronates. Although the coupling reaction with 1-hexenylboronate with (Z)-3-bromoacrylate gave a mixture of ethyl (2Z,4E)- and (2E,4E)-nonadienoates in a ratio of 63 : 37, it was found that the use of bis(diphenylphosphino)ferrocene as a ligand of palladium brought about the stereoselective coupling under mild conditions.
  • Hiroshi Matsubara, Koji Seto, Tadasu Tahara, Shigetoshi Takahashi
    1989 Volume 62 Issue 12 Pages 3896-3901
    Published: 1989
    Released: June 27, 2006
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    2,5-Diaryl-1,3,2-dioxaborinane derivatives having various terminal groups were synthesized and found to form mesomorphic phases in a wide temperature range. They provide a new series of liquid-crystalline compounds containing a boron atom in the principal structure.
  • Takashi Hoshino, Yoshio Imamura
    1989 Volume 62 Issue 12 Pages 3902-3905
    Published: 1989
    Released: June 27, 2006
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    The splitting of the methylene peaks in 1H NMR spectra was studied for alkyl compounds with various substituents in 1-chloronaphthalene solutions. The solvent shifts for the higher field split methylene peak and the α-methylene peak varied with a dependence on the magnitude of the electric group moment of the terminal substituent; those for the lower- and middle-field split methylene peaks and the terminal methyl peak remained constant. It was found that the different behaviors of the solvent shifts of the methylene signals could be ascribed to the origin of the peak splitting observed for long alkyl compounds.
  • Nobuyuki Matsushita, Norimichi Kojima, Toshiro Ban, Ikuji Tsujikawa
    1989 Volume 62 Issue 12 Pages 3906-3910
    Published: 1989
    Released: June 27, 2006
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    The low-energy absorption edge due to the intervalence charge-transfer (IVCT) transition from PtII to PtIV has been investigated at 4.2 K and room temperature in single crystals of [Pt(en)2][PtBr2(en)2]Y4 {Y=ClO4(PBC), HSO4(PBHS)}, [Pt(en)2][PtI2(en)2](HSO4)4·4H2O (PIHS) and [Pt(en)2][PtX2(en)2](SO4)2·6H2O {X=Cl(PCSW), Br(PBSW), I(PISW)}. The IVCT absorption edges in PCSW, PBSW, and PISW shifted to the lower-energy side (i.e. red shift), while those in PBC, PBHS, and PIHS shifted to the higher-energy side (i.e. blue shift) with an increase in temperature. We consider that the thermal effect of the valence fluctuation of the Pt mixed-valence state causes a red shift of the IVCT absorption edge and that the thermal effect of the hydrogen bond between the PtII complex ion and the PtIV complex ion causes a blue shift of the IVCT absorption edge. These two effects coexist and compete with each other in one complex. The dominant effect of the two effects determines the direction of the shift of the IVCT absorption edge, namely, the temperature dependence of the Pt mixed-valence state.
  • Kenji Murao, Naoki Tanaka, Kazuhiro Suzuki
    1989 Volume 62 Issue 12 Pages 3911-3918
    Published: 1989
    Released: June 27, 2006
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    Oxidation waves in cyclic voltammograms (CVs) observed during repeated potential cyclings of polypyrrole-as-deposited Pt/poly-1 electrodes (poly-1: poly[tris(4-vinyl-4′-methyl-2,2′-bipyridine)ruthenium(II) perchlorate]) in 0.1 M TBAP/acetonitrile, that lead to the bilayer (BL) electrochemistry, have been quantitatively analyzed. As the potential cycling is repeated, the CV change occurs, i.e., decrease of the peak current and positive shift of the peak potential. This is shown to be the result of logarithmic decrease in the complementary charge transfer coefficient β in the totally irreversible thin-layer (TITL) electrochemistry. kTL° (standard rate constant for polypyrrole oxidation) and CTL° (initial concentration of the reduced sites in polypyrrole) have been determined to be 5.50×10−9 cm mol−1 s−1 and 3.15×10−3 mol cm−3, respectively, by fitting CV data to the theory of the TITL model. The subsequent onset and growth of the CV waves in the higher potential region are explained as being due to progressive partitioning of polypyrrole sites from the TITL mode to the BL mode in which polypyrrole sites are oxidized. The partition coefficient θ, defined as the ratio of polypyrrole sites oxidized in the BL mode to all the polypyrrole sites, has been found to approximately depend on the logarithm of β. In the BL mode, a linear relationship is found between peak current and peak potential. Simulation of the CV waves has been performed based on the theoretical models of TITL and BL electrochemistry, and has revealed that a model assuming separation of polypyrrole sites into the TITL and BL modes prior to each cyclic sweep explains the occurrence of the significantly separated current peaks in both modes. These results are discussed in terms of Electrochemically driven Phase Separation (ECPS), in which the decrease in β is directly related to the separation of the mixed poly-1 and polypyrrole phase.
  • Masato Ito, Yoshio Matsunaga, Hiroyuki Matsuzaki, Saeko Shimojima
    1989 Volume 62 Issue 12 Pages 3919-3922
    Published: 1989
    Released: June 27, 2006
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    Alkylammonium benzene-, pyridine-3-, p-toluene-, and p-ethylbenzenesulfonates were found to be smectogenic when the cation carries an octyl or longer alkyl group. The thermal stability of the mesophase usually reaches its maximum at the octadecylammonium salt. The temperature range of stable existence is in the following order: pyridine-3-sulfonate>p-toluenesulfonate>benzenesulfonate>p-ethylbenzenesulfonate, suggesting the presence of a specific interaction between the ammonium ion and the nitrogen atom in the pyridine ring.
  • Yoshifumi Tanimoto, Masanobu Takashima, Michiya Itoh
    1989 Volume 62 Issue 12 Pages 3923-3931
    Published: 1989
    Released: June 27, 2006
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    The external magnetic field effects (MFE) on the biradicals generated from the intramolecular photoreactions of bifunctional chain molecules, α-(xanthone-2-carbonyloxy)-ω-(xanthene-2-carbonyloxy)alkanes (XO-n-XH, n=2–12) and Ar-12-XH (Ar=anthraquinone-4-carbonyloxy (AQ), 4-benzoylphenoxy (BP), and 4-acetylphenoxy (AP)) were studied by laser flash photolysis. All biradicals exhibit significant MFE. The simultaneous observation of the effects on the two radicals at the ends of the chain, generated from XO-12-XH, AQ-12-XH, and BP-12-XH, presents unequivocal evidence that the respective two radical centers correlate magnetically each other. The n dependence of the effects on biradicals generated from XO-n-XH indicates that the singlet–triplet degeneracy of the biradical occurs at the chain length of around n=6, i.e., the interradical distance of about 15 Å.
  • Mitsunobu Sato, Shigenobu Yano
    1989 Volume 62 Issue 12 Pages 3932-3938
    Published: 1989
    Released: June 27, 2006
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    The 2-hydroxy-1,3-propanediamine-N,N,N′,N′-tetraacetatocobaltate(III) complex has been optically resolved using strychnine nitrate. The crystal structure of the optically active complex with the resolving agent, (+)589-(STC)[Co(dhpta)]·1.5H2O has been determined from three dimensional X-ray diffraction data. The absolute configuration around the cobalt atom, to which two nitrogen and four oxygen atoms in the ligand are bonded nearly octahedrally, is Δ. The six-membered chelate ring adopts the λ-skew boat conformation. The intermolecular hydrogen bonding between the coordinated oxygen atom of the acetate ring and the protonated nitrogen atom of strychnine, which is one of the asymmetric centers, plays an important role in the diastereomeric discrimination. In contrast, the non-coordinated hydroxyl group in the complex ion does not interact directly with the strychnine molecule. The relationship between the absolute configuration around the cobalt center and the circular dichroism has been examined for the optically active complex ion.
  • Ch\={o}ki Fukuhara, Kazuhiko Tsuneyoshi, Kosho Katsura, Naohide Matsum ...
    1989 Volume 62 Issue 12 Pages 3939-3943
    Published: 1989
    Released: June 27, 2006
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    The title complexes have been synthesized in quantitative yield from [Cu(salpd)] and copper(II) acetate or copper(II) formate , where H2salpd represents N,N′-disalicylidene-1,3-propanediamine. [Cu(salpd-μ-O,O′)(μ-L)Cu(μ-CH3O)2Cu(μ-L)(salpd-μ-O,O′)Cu] crystallizes in the monoclinic space group P21/n with formula=Cu4C40H44N4O10, F.W.=995.0, a=11.826(2) Å, b=17.192(4) Å, c=9.836(2) Å, β=94.08(2)°, V=1994.8(7) Å3 and Z=2 (R=3.83%), where L=CH3COO. The complex forms a centrosymmetric molecule made up of two units of [Cu(salpd-μ-O,O′)(μ-CH3COO)Cu] bound by a pair of methoxo bridges; each terminal copper(II) ion forms four short bonds with N and O atoms of salpd and a slightly longer (2.235(4) Å) axial bond with one of the oxygens of the acetato group, whereas each inner copper(II) ion is also pyramidally coordinated by two methoxo oxygens, one of the acetato oxygens, and one of the bridging salpd oxygens, the distant axial position being occupied (Cu–O=2.323(3) Å) by the remaining bridging salpd oxygen. The magnetic susceptibilities of the complexes in the 86.8–299.0 K range have been analyzed on the basis of a four-spin model for the linear copper(II) complexes, and the values of g and Jij, based on the Heisenberg-type Hamiltonian H=−2ΣJijSi·Sj, have been estimated as g (average)=2.13, J12=−390 cm−1, J13=67 cm−1 and J14=34 cm−1 in the complex with acetate bridges, and as g (average)=2.20, J12=−263 cm−1, and J13=39 cm−1 and J14=J34=0 cm−1 in the complex with formate bridges, where the numbering refers to the 3–1–2–4 arrangement of the Cu2+ ions.
  • Shuji Kanemasa, Naoki Tomoshige, Eiji Wada, Otohiko Tsuge
    1989 Volume 62 Issue 12 Pages 3944-3949
    Published: 1989
    Released: June 27, 2006
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    A synthetic equivalent of parent azomethine imine is accessible by simple heating of ethyl 3-benzylcarbazate with paraformaldehyde under reflux in toluene in the presence of triethylamine, which effectively suppresses the undesired formation of imine dimers. The resulting imines can be trapped with a variety of dipolarophiles.
  • Masao Shiozaki, Noboru Ishida, Sadao Sato
    1989 Volume 62 Issue 12 Pages 3950-3958
    Published: 1989
    Released: June 27, 2006
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    A bicyclic β-lactam (4), obtained from 2,3-O-isopropylidene-D-glyceraldehyde in 3 steps, was converted to methyl 2-benzamido-2-deoxy-5,6-O-isopropylidene-3-O-(3-chlorobenzoyl)-α-D-altrofuranoside (24) through an additional 8 steps by utilizing the β-lactam nitrogen via the oxidative decarboxylation of diacyl peroxide (23). Additionally, it was shown that the bicyclic β-lactam intermediate is a suitable precursor for 2-amino-3-(branched-chain)-2-deoxy-D-furanoside derivatives.
  • Yoshiharu Yoneyama, Yu Akaki, Tsutomu Kato
    1989 Volume 62 Issue 12 Pages 3959-3962
    Published: 1989
    Released: June 27, 2006
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    A number of model compounds having representative coal structures were treated with zinc–butyl iodide under mild conditions. Gas chromatography and gas chromatography/mass spectrometry were used to identify the reaction products. Polynuclear aromatic compounds gave the butyl-substituted and butyl-addition products. In a reaction of anthracene, its aromatic backbone was cleaved. Alkoxynaphthalene and dibenzyl ether were butylated along with cleavage of ether linkage, while diphenyl ether gave only the butyl-substituted products without cleavage. Butylation and cleavage also took place in the reactions of diphenylmethane and bibenzyl. In the cases of substitution reaction, some butyl groups were rearranged to s-butyl. Because the formation of the most reaction products is interpreted by a similar mechanism to that of Friedel–Crafts alkylation and the formation of some butyl-addition products of polynuclear aromatic compounds is explained by assuming a radical reaction mechanism, it is suggested that both alkyl cation reaction and alkyl radical reaction occur competitively.
  • Sadao Sato, Yoichi Habata, Masaru Sato, Sadatoshi Akabori
    1989 Volume 62 Issue 12 Pages 3963-3967
    Published: 1989
    Released: June 27, 2006
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    The reaction of 1,1′-bis(6-chloro-1,4-dioxahexyl)ruthenocene with disodium 1,2-ethanedithiolate gave 1,4,13,16-tetraoxa-7,9-dithia[16](1,1′)ruthenocenophane (5) in 63% yield. The reaction of 5 with HgCl2 in acetonitrile gave a 1: 2 complex (6) in 47% yield. The crystal structure of complex 6 and its metal free ligand 5 were determined by an X-ray method. Crystal data: 5, triclinic, a=11.128(2), b=12.720(2), c=10.196(2)Å, α=113.55(1), β=64.13(1), γ=122.01(1)°, U=1074.1 Å3. P\bar1, Z=2, Dc=1.54 Mg m−3, μ(Mo Kα)=9 mm−1. R=0.028. 6, triclinic, a=16.595(4), b=12.645(3), c=7.401(1)Å, α=104.92(1), β=92.37(1), γ=69.38(2)°, U=1402.4Å3, P\bar1, Z=2, Dc=2.46 Mg m−3, μ(Mo Kα)=12.2 mm−1, R=0.081. The X-ray analysis of 6 revealed that one Hg atom was bonded to the Ru atom of the ruthenocene nucleus with a distorted trigonal-planar configuration and another Hg atom was bonded to the two sulfur atoms of the macrocycle. This result is completely different from that obtained regarding complex 4,7,10,13-tetraoxa-1,16-dithia[16](1,1′)ruthenocenophane with HgCl2.
  • Hisao Suzuki, Akihiko Tomoda, Mitsuo Ishizuka, Akira Kaneko, Masami Fu ...
    1989 Volume 62 Issue 12 Pages 3968-3971
    Published: 1989
    Released: June 27, 2006
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    The thermal and photochemical stabilities of 2-[1-(2-phenyl-5-methyl-4-oxazolyl)]alkylidenesuccinic anhydrides (1) and (2) were studied. These compounds showed good thermal stabilities in PMMA film and low photochemical fatigue (PF≤0.03% /cycle) in a dilute toluene solution in the presence of air, compared with 3-furyl fulgide (3). Although in PMMA film the photochemical fatigue resistance property of the fulgides was poor, in comparison with that in solution, the addition of an organo-nickel stabilizer improved the property.
  • Yasuo Kubo, Mikako Nanba, Etsuko Hayashi, Takeo Araki
    1989 Volume 62 Issue 12 Pages 3972-3977
    Published: 1989
    Released: June 27, 2006
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    Irradiation of acetonitrile–methanol (2:1 v/v) solutions of N-methyl-9,10-phenanthrenedicarboximide (3) with alkenes 5ag gave methanol-incorporated adducts (9cf) at a carbonyl carbon atom in 3, those (10c,f) at a phenanthrene-ring carbon atom, and a methanol-adduct 11g to alkene 5g, together with products 4, 6b,eg, 7b,eg, and 8e,f obtained by the photoreactions in benzene. The concentration effect of alkenes 5e,f on yields of products 6e,f, 7e,f, 8e,f, 9e,f, and 10f showed that both 9e,f and 10f arose from a relatively short-lived singlet excited state of 3. The values of the free-energy change associated with an electron transfer (ΔGet) from alkenes 5ad,g to the singlet excited state of 3 and fluorescence quenching rate constants support a photochemical electron transfer mechanism for the methanol-incorporated addition. Both LiClO4 and BU4NClO4 caused only slight decreases in the relative ratios 10c/9c indicating that both the methanol-incorporated addition at the phenanthrene-ring carbon atom and that at the carbonyl carbon atom might arise from a contact ion pair state. The fact that the methanol-incorporated addition at the arene-ring carbon atom was observed only in the reaction of 3 in a series of N-methylarenedicarboximides, possessing a five-membered imide ring, is interpreted on the basis of the spin density of the radical anions of the imides derived from the photochemical electron transfer.
  • Kin-ichi Tadano, Kei-ichi Shimada, Akiko Miyake, Jun Ishihara, Seiichi ...
    1989 Volume 62 Issue 12 Pages 3978-3986
    Published: 1989
    Released: June 27, 2006
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    The (E)- and (Z)-isomers (2E and 2Z) of 3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-α -D-xylo-hept-5-eno-1,4-furanose were subjected to Claisen rearrangement with triethyl orthoacetate. Possible two diastereomers were obtained as a 1 to 1 mixture from both of 2Z and 2E, and also from their 3-hydroxy or 3-siloxy derivatives. On the other hand, the rearrangement of the corresponding D-ribo derivative (13Z) and its 3-O-(t-butyldiphenylsilyl) derivative proceeded with a high level of diastereoselectivity. By contrast, the (E)-isomer of 13Z showed no significant stereoselectivity, resulting in the formation of a diastereomeric mixture. The configurations of the introduced stereogenic centers by the rearrangements were unambiguously established by chemical transformations.
  • Katsuyuki Ogura, Michio Ishida, Makoto Fujita
    1989 Volume 62 Issue 12 Pages 3987-3993
    Published: 1989
    Released: June 27, 2006
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    Reduction of a 2-(p-tolylsulfinyl)cycloalkanone with sodium borohydride in methanol–triethylamine is accompanied by rapid epimerization at C2. Under the conditions employed here, the π-facial selectivity of the reduction is directed by the side chain chirality and, among four possible isomers of the corresponding cycloalkanol, one isomer is given with high selectivities up to 85%.
  • Kinya Sakanishi, Masato Ohira, Isao Mochida, Hiroshi Okazaki, Mahito S ...
    1989 Volume 62 Issue 12 Pages 3994-4001
    Published: 1989
    Released: June 27, 2006
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    The reactivities of several polyaromatic hydrocarbons (pyrene: P, fluoranthene: FL, anthracene: An, fluorene: F, acridine: Ac, and carbazole: C) in the catalytic hydrogenation were studied and compared over supported noble metals (Pt, Pd, Rh, and Ru on a carbon or alumina support). The specific reactivity and selectivity were found to be strongly dependent upon the combination of the catalyst species and the substrate. The catalysts exhibited the activity order of Rh > Pd >> Pt > Ru for tricyclic aromatics of An, F, Ac, and C, although the catalysts provided very variable selectivities of the partially hydrogenated products which were produced via both consecutive and competitive routes, apparently according to the type of ring-skeleton and the presence of a nitrogen atom. The reactivity of the starting substrates and intermediates are compared to the quantum chemical reactivity indices, calculated based on MNDO (modified neglect of diatomic overlap). The values of the LUMO electron density, the π-bond order, and the stability of the product appear to govern the reactivity and selectivity of the hydrogenation, depending upon the combination of the catalyst species and the substrate. No hydrogenation of a substrate proceeds when its reactivity indices are less than the threshold value, which is subject to the activity of the catalyst and the reaction conditions defining product selectivity via both competitive and consecutive schemes.
  • Walid Ahmad Badawi
    1989 Volume 62 Issue 12 Pages 4002-4005
    Published: 1989
    Released: June 27, 2006
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    Analysis of the experimental results which have been obtained from our studies on the ternary systems Pb–Sb–Sn, Bi–Pb–Sn, and Bi–Cd–Sn revealed a new effect: deduction of a straight line obtained by interpolation between the pairs Sb–Pb and Sb–Sn at xPb=xSn=0.5 from the partial enthalpy of mixing of antimony, hSbm, yields a remainder quantity, rhSbm. The minimum of this remainder lies at the section drawing xPb/xSn=1. Further studies on the systems Bi–Pb–Sn and Bi–Cd–Sn indicated that the present “r-effect” is probably a general property of ternary solutions. The sign of the remainder rhim is opposite to that of hm of the pair of components existing vis-a-vis a third apex-component in the same ternary system. Systems of strong heteropolar character which indicate Wagner effect overlapped by III–V one could also exhibit r-effectt. Rules for the mixing behavior in binary systems are in some cases not applicable on the corresponding pairs in the ternary solutions.
  • José Muñoz Embid, José M\b{a} Fornies-Marquina, S ...
    1989 Volume 62 Issue 12 Pages 4006-4008
    Published: 1989
    Released: June 27, 2006
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    A study of the dielectric relaxation process of 1-iodoalkanes (from 1-iodopropane to 1-iodohexadecane) was carried out by measuring their static dielectric constants at 2 MHz and complex dielectric permittivities at 9.23 and 15.05 GHz, in the range of temperature 293.15–343.15 K. The 1-iodoalkanes are classified as belonging to an unsymmetrical distribution of relaxation times of Cole–Davidson type. Activation enthalpies for the relaxation process are obtained by fitting the data of relaxation time as a function of temperature 1to the Eyring equation. The influence of the aliphatic chain length in the 1-iodoalkane on the characteristic parameters of the relaxation process is discussed.
  • Kamla Sharma, Aditya Prakash, Raj N. Mehrotra
    1989 Volume 62 Issue 12 Pages 4009-4015
    Published: 1989
    Released: June 27, 2006
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    A kinetic study on the oxidation of phosphinic(hypophosphorous) and phenylphosphinic acids by trispolypyridyliron(III) complexes using excess of either phosphinic or phenylphosphinic acid has been made in perchloric acid. The pseudo first-order rate constant kobs, with respect to iron(III) complex, is independent of [H+]. The results indicated that phenylphosphinic acid is more reactive than phosphinic acid towards any given iron(III) complex. The formation of an intermediate complex is indicated by the kinetics and supported by the spectrophotometry of the reaction mixture. The differences in the observed thermodynamic parameters of this intermediate complex, probably an outer-sphere complex, and those predicted by the Fuoss equation are discussed. It is suggested that the ‘inactive’ form of either of the acid is reactive towards the iron(III) complexes. It is also shown that the rate of disproportionation of the intermediate complex is not affected by the form of phosphinic or phenylphosphinic acid entering into the complex formation. The values of β2 and k1, the equilibrium constant for the formation of the oxidant-substrate complex and the rate limiting constant for its disproportionation respectively, are reported together with respective thermodynamic and activation parameters.
  • O. V. Mikhailov, G. K. Budnikov
    1989 Volume 62 Issue 12 Pages 4016-4020
    Published: 1989
    Released: June 27, 2006
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    Complexing processes occurring between reactive matrices obtained from Fe(III), Co(III), Ni(II), Cu(II) hexacyanoferrates(II), and alkaline solutions of various nitrogen-sulfur-containing chelating ligands in thin gelatin layers have been studied. With Fe(III) and Cu(II) hexacyanoferrates, complexing process is found out to proceed according to SN1 mechanism, while in Co(III) and Ni(II) hexacyanoferrates matrices, SN2 mechanism is realized. The schemes of the processes proceeding in each of the above matrices are given. The examples of the kinetic curves for particular systems “hexacyanoferrate(II)-ligand” as well as spectral characteristics of thin gelatin layers containing chelate complexes formed as a result of the chelating process are presented. The possibility of practical utilization of complexing processes studied for obtaining non-silver photographic images from light-resistant metallorganic dyes is reported.
  • Graeme H. Searle
    1989 Volume 62 Issue 12 Pages 4021-4032
    Published: 1989
    Released: June 27, 2006
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    The substitution reaction [Co(NH3)5(H2O)]3++hexacyclen·3H2SO4+6base+charcoal gives mer-[Co(hexacyclen)]3+ as the major product, and the equilibrium proportion of the fac isomer is <1%. The commercial hexacyclen contains linpen (the open chain analogue of hexacyclen, generated by an elimination reaction in the Richman-Atkins cyclization synthesis procedure), so that the synthesis of complex yields [Co(linpen)]3+ isomers as co-products which complicate the isolation of the pure [Co(hexacyclen)]3+ isomers. Procedures are now given for obtaining the mer and fac isomers pure. In particular, the unstable fac isomer is obtained by isomerization of the mer in base in the presence of the strongly associating anion PO43−. This yields the new equilibrium mixture mer: fac: hydrolysis products=71:18:11, wherein the fac proportion is enhanced twenty times, enabling the pure fac isomer to be obtained in quantity. For the base-catalyzed isomerization reaction facmer in NaOH solutions at 50 °C, procedures are given for following the reaction by analyses of samples using ion-exchange HPLC (Na2SO4 elution) and by spectrophotometry. The mechanism must involve intramolecular bond rupture, but the kinetic results are not consistent with a simple SN1CB mechanism, and a two-step process involving an intermediate is indicated.
  • Kunio Miki, Nobutami Kasai, Isao Endo, Sanshiro Komiya
    1989 Volume 62 Issue 12 Pages 4033-4035
    Published: 1989
    Released: June 27, 2006
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    The structure of the novel heterodinuclear organometallic complex, [(cod)(Ph)Pt–W(CO)35-C5H5)] has been determined by X-ray crystallography; the Pt–W bond distance is 2.844(1)Å.
  • Shinsaku Yamazaki, Tomoharu Ama, Masashi Hojo, Tamio Ueno
    1989 Volume 62 Issue 12 Pages 4036-4038
    Published: 1989
    Released: June 27, 2006
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    3-Thio-2,4-pentanedionate (tac) complex of platinum(II), [Pt(tac)(PMe2Ph)2], has been prepared by treating [PtCl(PMe2Ph)3][PF6] with 2,3-dithio-1,1,4,4-tetraacetylbutane in a KOH/methanol–acetone mixed solution. This complex has been characterized by IR, 1H, 13C, and 31P NMR, secondary ion mass and ESR spectroscopy and cyclic voltammetry.
  • Kazuo Eda, Noriyuki Sotani
    1989 Volume 62 Issue 12 Pages 4039-4040
    Published: 1989
    Released: June 27, 2006
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    It was found that hydrogen molybdenum bronze, H0.3MoO3, turns into a hydrogen insertion compound of hydrated molybdenum oxide in a 1M HCl aqueous solution at 353 K. It was predictable that the compound has a composition of H0.15MoO3·0.88H2O and is identical with Mo8O15(OH)16 or a similar compound.
  • Naohide Matsumoto, Takashi Kondo, Masahito Kodera, Hisashi Okawa, Sige ...
    1989 Volume 62 Issue 12 Pages 4041-4043
    Published: 1989
    Released: June 27, 2006
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    The magnetic susceptibility measurement down to the liquid helium temperature and the single-crystal X-ray analysis of alkoxo-oxygen bridged tetranuclear copper(II) complex [CuL]4 have been performed, where H2L is a tridentate ligand derived from condensation of 3-ethoxymethylene-2,4-pentanedione and 2-aminoethanol. The magnetic data demonstrated that the four unpaired electrons of the four copper(II) ions are ferromagnetically coupled, the ground spin state of the cubane molecule being S=2. The structural analysis has confirmed several structural features, i.e., the distorted Cu4O4 cubane structure, the square pyramidal coordination geometry, nearly perpendicular arrengement between adjacent basal coordination planes, and inequivalent Cu–O bond distances.
  • Mutsuo Kodama, Hideki Anan, Tohru Koike, Eiichi Kimura
    1989 Volume 62 Issue 12 Pages 4044-4046
    Published: 1989
    Released: June 27, 2006
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    The equilibria of complexation reactions of dioxo[16]aneN5, dioxo[18]aneN6, and their related compounds with copper(II) ions were determined potentiometrically. Making a sharp contrast to the 13–15-membered monocyclic dioxotetramine system, they interact with copper(II) ions in their neutral and doubly deprotonated forms, L and H−2L2−, yielding stable CuL2+ and CuH−2L0 complexes.
  • Shuji Emori, Satoru Matsunaga, Miyako Goto
    1989 Volume 62 Issue 12 Pages 4047-4049
    Published: 1989
    Released: June 27, 2006
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    Various copper(II) 3- and 4-substituted and 3,5-disubstituted benzoate adducts with quinoline and 4-methylquinoline have been prepared, and characterized by means of magnetic susceptibility and IR spectroscopy measurements. The variation of their magnetic moments is discussed in terms of the acidities of their parent acids and the resonance effects of 4-substituents.
  • Hiroshi Yamamoto, Takehiko Nishio, Masatoshi Hirayama, Masamoto Akutag ...
    1989 Volume 62 Issue 12 Pages 4050-4052
    Published: 1989
    Released: June 27, 2006
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    5-Arylamino-3-isopropyl-6-methyl-6-phenyl-1,2,4-trioxanes were synthesized by autoxidation of imines in the presence of isobutyraldehyde. Their four isomers have been identified and the anomerization of 5-arylamino-1,2,4-trioxanes has been detected by the 13C NMR spectra in chloroform-d.
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