Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
68 巻 , 6 号
選択された号の論文の31件中1~31を表示しています
  • Akira Nakamura
    1995 年 68 巻 6 号 p. 1515-1521
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Chemistry of transition metal complexes of organic conjugated systems, e.g. 1,3-diene, cyclobutadiene, and hexapentaene, is reviewed mainly based upon the author’s investigation. Some recent examples of dπ–pπ conjugated systems with multiple metal–metal and metal–carbon bonds are also described.
  • Takuo Sone, Satoshi Ozaki, Noriko C. Kasuga, Atsushi Fukuoka, Sanshiro ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1523-1533
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    cis-Dimethyl(η1-allyl)(triphenylphosphine)gold(III), cis-[AuMe2(η1-allyl)(PPh3)] (η1-allyl = allyl (1), crotyl (2), methallyl (3)) has been synthesized by reaction of cis-[AuMe2X(PPh3)] (X = I, NO3) with corresponding Grignard reagents. X-Ray structure analysis of 2 shows that 2 has a typical square planar cis configuration and the crotyl ligand binds to Au by η1-mode: orthorhombic, space group P212121, a = 9.816(2), b = 23.208(4), c = 9.5290(9) Å, Z = 4, R(Rw) = 0.037(0.041) with use of 2551 reflections. Reactions of 2 with HCl and Br2 selectively give 1-butene and 3-bromo-1-butene, respectively, indicating γ-regioselectivity of the reactions. Compounds 13 react with aldehydes and ketones to give the corresponding homoallyl alcohols. C–C bond formation also takes place at the γ-position of η1-allyl moiety selectively. The rate of the allylation reaction of carbonyl compounds decreases in the order of methallyl (3) > allyl (1) > crotyl (2) gold(III) complexes. The homoallyl alcohol formed by the reaction of 2 with benzaldehyde is a diastereoisomeric mixture of 2-methyl-1-phenyl-3-buten-1-ol, with high anti selectivity. Both the reaction rate and anti selectivity in the allylation reaction were reduced by addition of tertiary phosphines such as PPh3 and PCy3, and a 6-membered transition state has been proposed, which indicates coordination of the carbonyl group to a T-shape Au intermediate produced by dissociation of the PPh3 ligand.
  • Hitomi Suzuki, Shuji Yonezawa, Tadashi Mori
    1995 年 68 巻 6 号 p. 1535-1544
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Cyclic acetals derived from aromatic carbonyl compounds can be nitrated smoothly with nitrogen dioxide in ice-cooled dichloromethane or acetonitrile in the presence of ozone and magnesium oxide to give ortho- and para-nitro derivatives as the major product in good combined yields, the acetal ring as a protective group remaining almost intact. An acylal derived from benzaldehyde similarly undergoes nitration on the aromatic ring to give an isomeric mixture of three nitro compounds, in which the ortho and meta isomers predominate, while aromatic orthoesters are rapidly decomposed to give simply the parent esters. Ring nitration under neutral conditions has been interpreted in terms of a nonclassical mechanism, in which nitrogen trioxide is involved as the initial electrophile.
  • Tatsuo Erabi, Kiyoharu Matsumoto, Tsutomu Okamoto, Megumi Moriuchi, Ts ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1545-1550
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    An anodic photocurrent was generated when an SnO2 electrode, which was immersed in a culture medium of a photosynthetic bacterium, Rhodospirillum rubrum, or in a buffer suspending the cell body, was illuminated under potentiostatic conditions. The anodic photocurrent was enhanced about four times with addition of methyl viologen (MV) to the cell suspension, but was suppressed with addition of 1,1′-ethylene-2,2′-bipyridinium dibromide (EBP). On the other hand, it was observed spectrophotometrically that EBP was reduced by Rs. rubrum cells about ten times faster than MV. The disagreement in both data of photocurrent and of reduction rate suggests this to be due to the difference of penetrability of the salts through the cell wall and membrane. This suggestion was confirmed from cyclic voltammetric results of the reagents dissolved in the cell suspension.
  • Kaori Ueno, Umpei Nagashima, Keiko Takano, Haruo Hosoya
    1995 年 68 巻 6 号 p. 1551-1557
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Spherical charge analysis based on the difference of spherically averaged electron density (Δρ0(R)) was extended to various open shell states of CH2 using wave functions obtained from RHF, UHF, and full CI calculations. The Δρ0(R) values around C and H atoms were calculated with natural orbitals to interpret the oxidation state of component atoms for the lowest and second lowest 3B1 and 1A1 states. Modified oxidation numbers are assigned systematically to the component atoms in CH2 based on the extended Δρ0(R) analysis.
    The effect of electron correlation on the Δρ0(R) values around the nucleus in this system was found to be so small that the modified oxidation numbers are not changed by fair introduction of electron correlation effect into the calculation. The difference of spin multiplicity and state symmetry on the Δρ0(R) curves is also discussed.
  • Tsuneo Fujii, Yuichiro Hisakawa, Edmund J. Winder, Arthur B. Ellis
    1995 年 68 巻 6 号 p. 1559-1564
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The effects of heat (130, 200, and 600 °C) and added gases (NH3 and SO2) on the photoluminescence of CdS particles prepared by the sol–gel method were examined in order to elucidate the influence of the chemical environment on photoluminescence. Green and red photoluminescence (PL) were observed in non-heated samples. Exposure of the added gasses to the samples caused characteristic decreases of the green and red PLs. The intensity ratio of the green PL to that of the red PL for a 600-R sample (heated at 600 °C in H2S) showed a reversible behavior against exposure to SO2. These results indicate that there is adduct formation between CdS and SO2. The PL changes were fitted to the Langmuir adsorption isotherm model, and yielded the adduct formation constants. There are three emitting and three final states in the specimen.
  • Akira Shimoyama, Naoko Kisu, Kaoru Harada, Shigeo Wakita, Akira Tsunek ...
    1995 年 68 巻 6 号 p. 1565-1568
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Fatty acids extracted from archaeological pottery vessels (B.C. 900—720 y) excavated at Tell Mastuma, Syria, are characteristic of individual vessels. The molecular-distribution patterns of n-fatty acids of these vessels are different from those of the underfloor soil and a human hand, indicating that the fatty acids recovered are proper to the samples. The lamps show a predominance of hexadecanoic and octadecanoic acids with a near absence of other acids in the patterns, suggesting that olive oil was used in the lamps. On the other hand, large pottery jars show a clear presence of nonanoic acid in their patterns. The acid presence is also strikingly noted in carbonized olive, suggesting that olive and/or a chemically olive-related material was stored in the jars. The relative concentration of cis-9-octadecenoic acid to octadecanoic acid decreases drastically from modern olive pulp to carbonized olive, and further in the jars and lamps. Apparently, a degradation of the acid had occurred intensely during burial in the soil. A comparison of the molecular-distribution patterns of the jars and lamps to the carbonized olive and olive pulp allows one to conclude that olive and its oil were commonly utilized at the tell.
  • Hiroshi Miyasaka, Manabu Kiri, Kazuhiro Morita, Noboru Mataga, Yoshifu ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1569-1582
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Photoinduced hydrogen abstraction (HA) processes of 1-(4-anilinophenyl)-2-(4-benzophenoxy)ethane, 1-(4-anilinophenyl)-3-4-benzophenoxy)propane, and 1-(4-anilinophenyl)-8-(4-benzophenoxy)octane (BP–O–(CH2)n–O–DPA: n = 2, 3, and 8) in benzene, acetonitrile, and N,N-dimethylformamide solutions were investigated by means of picosecond transient absorption spectroscopy. In benzene solution, apparent mechanism of the hydrogen abstraction reaction was “direct” process and no absorption spectrum of the charge separated state was observed. The decay of triplet benzophenone moiety (3BP*) was regulated by the dynamic rearrangement process of the mutual geometry between 3BP* and DPA to a more compact one.
    In polar solutions, the electron transfer (ET) from DPA to 3BP* moiety took place in addition to the direct HA from DPA by 3BP*. The rate of the ET reaction was regulated mainly by the distance between the reactant moieties. Moreover, the intra-ion pair (IP) proton transfer (PT) resulting in the HA product formation was observed, although such PT process in the IP state between the unlinked 3BP* and the secondary amine was not observed. By integrating the present results on the linked systems with those of the unlinked systems, the role of the ET or CT interaction in the HA process of 3BP* from the secondary amine was discussed.
  • Kazuyasu Ibuki, Masakatsu Ueno
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1583-1588
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The translational friction and the viscosity B coefficients for a spherical molecule in solution are calculated from the Navier–Stokes equation for a continuum with space-dependent viscosity. We test three functions for the space dependence of the viscosity as models for the “local viscosity”. Each function is a smooth function of distance from the solute center and approaches the viscosity in the bulk at an infinite distance. For all the three functions studied, the translational friction and the viscosity B coefficients decrease with decreasing viscosity in the vicinity of the solute, and the effect of the space-dependent viscosity is larger for the B coefficient than for the translational friction coefficient. These results can explain the observed shortcomings of the ordinary continuum model with space-independent viscosity. This confirms the validity of the use of the viscosity B coefficient as a measure of the structure-breaking effect which is closely related to the idea of the “local viscosity”.
  • Neti Sumita Rao, Deen D. Mishra, Ram C. Maurya, Neti Nageswara Rao
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1589-1592
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The synthesis and characterisation of some 8-coordinate cis-dioxomolybdenum(VI) complexes of Schiff bases derived from 4-aminoantipyrine and 4-acetyl-3-methyl-1-phenyl-2-pyrazolin-5-one, 3-methyl-1-phenyl-4-propionyl-2-pyrazolin-5-one, and 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one are reported. Spectroscopic and other analytical data reveal that these Schiff bases behave as monobasic tridentate ligands and react with [MoO2(acac)2] in 2 : 1 ratio to give diamagnetic molybdenum(VI) mononuclear complexes having the general formula cis-MoO2(L)2 (L = Schiff base). These complexes were characterised by elemental analysis, molar conductance, IR, UV-vis, 1H NMR, and cyclic voltammetry.
  • Takashi Komorita, Akira Fuyuhiro, Kazumi Tanimoto, Koji Yamauchi, Kazu ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1593-1599
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Several square-planar complexes of the [PtCl(aaa-N,N′)(dmso-S)] type were prepared (aaa = amino acid amidate, dmso = dimethyl sulfoxide). The crystal and molecular structures for cis(NH2,S)-[PtCl(DL-alaa)(dmso)]·H2O (4) and trans(NH2,S)-[PtCl(DL-vala)(dmso)] (3b) were determined by X-ray diffraction (alaa = alaninamidate, vala = valinamidate). The crystal of 4 was triclinic, space group with a = 9.144(2), b = 9.172(3), c = 7.371(2) Å, α = 109.41(2)°, β = 99.69(2)°, γ = 76.13(3)°, Z = 2, and final R = 0.029 and RW = 0.034. The crystal of 3b was monoclinic, space group P21 with a = 7.158(2), b = 9.948(2), c = 8.741(2) Å, β = 102.76(2)°, Z = 2, and final R = 0.041 and Rw = 0.050. Both complexes were found to contain a carboxamidato group coordinating to platinum(II) through the nitrogen atom. A larger trans influence was observed for the coordinating carboxamidato nitrogen atom than for the amino one. The prepared complexes were characterized by NMR, visible and UV, and CD spectra in comparison with the complexes of [PtCl(aa-N,O)(dmso-S)] type (aa = amino acidate).
  • Kazunaka Endo, Masahiko Saikawa, Manabu Sugimoto, Masahiko Hada, Hiros ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1601-1605
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Electron absorption spectra of [RhCl6]3− and [RhCl5(H2O)]2− complexes are studied theoretically by the ab initio symmetry adapted cluster (SAC)/SAC-CI method. Two maximum peaks of the visible absorption spectra in the range of 300—600 nm observed in aqueous solution are assigned to (1T1g; 1T2g) and mixing-(1B1, 1A2, 1B2; 2B1, 2A2, 2B2) states for [RhCl6]3− and [RhCl5(H2O)]2− complexes, respectively, in good agreement. These states are due to the forbidden d–d transitions from the Rh(dπ) + Ligand(pπ) bonding MOs to the Rh(dσ)-Ligand(pσ) antibonding MOs, leading to an weakening of the metal–ligand bonds.
  • Mayumi Danjo, Yoshinobu Baba, Mitsutomo Tsuhako, Shunro Yamaguchi, Mas ...
    1995 年 68 巻 6 号 p. 1607-1612
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The intercalation of alkyltrimethylammonium ions into γ-titanium phosphate, Ti(HPO4)2·2H2O (γ-TiP), was investigated to clarify the mechanism of intercalation of quaternary ammonium ions into the layered phosphate. Alkyltrimethylammonium ions with short alkyl chains (the number of carbon atoms, n = 6 to 10) were scarcely intercalated into γ-TiP, while those with long alkyl chains (n = 12 to 18) were easily intercalated and formed a monolayer in the interlayer region, in which the alkyl chains inclined at 57.4° to the γ-TiP layers. The increase of the number of carbon atoms in alkyl chains and the volume of the solvent in the reaction solution led to the increase of the uptakes of quaternary ammonium ions. Based on these results, some bactericides with quaternary ammonium ion structure were then intercalated into γ-TiP, and the products obtained were stable to heat.
  • Saidul Zafar Qureshi, Mubeen Ahmad Khan, Nafisur Rahman
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1613-1617
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Zirconium(IV) arsenate vanadate was prepared by adding a mixture comprising 0.05 M sodium hydrogen arsenate and 0.05 M sodium metavanadate to an aqueous solution of zirconium(IV) dichloride oxide (0.05 M) in different volume ratios at pH 1. The material possessed a good ion-exchange capacity of 1.20 and 1.30 meq g−1 of exchanger for the Na+ and K+ ion, respectively, and was fairly stable in dilute mineral acids, but insoluble in water, acetic acid, formic acid, ethanol, and 1,4-dioxane. The distribution coefficients of a large number of metal ions were determined in different solvent systems.
  • Takayoshi Suzuki, Kazuo Kashiwabara, Junnosuke Fujita
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1619-1626
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    A new phosphine ligand, 8-(dimethylphosphino)quinoline (Me2Pqn), and its palladium(I or II) complexes, [PdX2(Me2Pqn)] (X = Cl (1a), Br (1b), and I (1c)), [Pd(Me2Pqn)2](BF4)2 (2b), and [Pd2Cl2(Me2Pqn)2] (3), have been prepared and characterized. The structures of 2b and 3 have been determined by X-ray analysis. The crystal data and final R values are: for 2b, FW = 658.42, monoclinic, P21/n, a = 17.453(2), b = 10.453(2), c = 14.928(2) Å, β = 105.63(1)°, V = 2622.8(5) Å3, Dx = 1.667 Mg m−3, and Z = 4, R = 0.071 for 3908 reflections (|Fo| ≥ 3σ(|Fo|)); for 3, MW = 662.64, monoclinic, P21/n, a = 16.429(1), b = 12.191(1), c = 12.821(1) Å, β = 92.673(8)°, V = 2565.1(4) Å3, Dx = 1.714 Mg m−3, and Z = 4, R = 0.056 for 5136 reflections (|Fo| ≥ 3σ(|Fo|)). In 2b the square coordination plane formed by two long Pd–N (2.138(9) and 2.135(8) Å) and two Pd–P bonds (2.243(3) and 2.237(3) Å) is slightly distorted towards tetrahedral geometry, the dihedral angle between the two chelate planes formed by the Pd, P, and N atoms being 10.3(2)°. 3 is a dinuclear complex with a Pd–Pd bond (2.542(1) Å), Me2Pqn chelates to one Pd(I) center, and the N donor atom occupies the trans position to the Pd–Pd bond. The dihedral angle between the two coordination planes linked by the Pd–Pd bond is nearly a right angle, 82.13(6)°.
  • Mutsuo Kodama, Tohru Koike, Eiichi Kimura
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1627-1633
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    We have studied the complexation reaction of a newly synthesized 26-membered octaaza macrocycle, 3,6,9,17,20,23,29,30-octaazatricyclo[23.3.1.1.11,15]triaconta-1(29),11,13,15(30),25,27-hexaene-2,10,16,24-tetraone (TOBP, L), with a Cu(II) ion by pH-metric titration. It accomodates two copper(II) ions in its macrocyclic cavity with a simultaneous dissociation of the four amide protons to yield a binuclear complex designated as [Cu2H−4L]°. The formation constant of [Cu2H−4L]°, KCu2H−4L ( = [Cu2H−4L°][H+]4/[Cu2+]2[L]), was found to be (3.5 ± 0.2) × 10−12 mol2 dm−6. At the dropping mercury electrode the Cu(II) binuclear complex gave two reduction steps of equal height in a borate buffer solution, corresponding to the following reduction scheme:
  • Hideyuki Sawatari, Eiji Fujimori, Akihide Itoh, Masahide Aikawa, Hirok ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1635-1640
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    A hyphenated system of inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) combined with aid of optical fiber was developed for versatile simultaneous multielement measurement of the elements from the major to ultratrace levels. In the present system, the emission signals from the argon ICP equipped for ICP-MS were led through optical fiber to a sequential-type monochromator for ICP-AES measurement. In consequence, the dynamic range of 9 orders of magnitude from a few pg ml−1 up to ca. 1000 μg ml−1 was obtained, which allowed the simultaneous determination of a variety of elements in the wide concentration range by ICP-MS and/or ICP-AES. The present system was applied to simultaneous multielement analysis of rock and seawater samples.
  • Nobushige Yamamoto, Tetsuya Yamane, Tetsu Tatsuma, Noboru Oyama
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1641-1645
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Electrochemical deposition of silver from a 1 mM AgNO3 aqueous acidic solution at 20 μA cm−2 was monitored by means of in-situ quartz crystal impedance (QCI) technique, in-situ quartz crystal microbalance (QCM) technique, ex-situ QCI technique and atomic absorption spectroscopy. However, the mass evaluated from the data obtained in the in-situ QCI and QCM measurements on the basis of Sauerbrey equation deviated from intrinsic mass of the deposited silver because of a low deposition efficiency, liquid viscously or rigidly coupled with the resonator and/or stress generated in the deposited layer. Thus one must pay attention to these factors when one calibrates a quartz crystal microbalance on the basis of electrochemical deposition of a metal. In-situ QCI method utilizing a network analyzer is shown to be a powerful technique for simultaneous and qualitative monitoring of mass and surface structure changes. For the quantitative mass measurements, the mass sensitivity must be calibrated using another direct method such as atomic absorption spectroscopy.
  • Makoto Handa, Yasuyoshi Sayama, Masahiro Mikuriya, Ryoji Nukada, Ichir ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1647-1653
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    A nitroxide complex, [Ru2(O2CCMe3)4(tempo)2][Ru2(O2CCMe3)4(H2O)2](BF4)2 (tempo = 2,2,6,6-tetramethylpiperidine-1-oxyl) has been prepared and characterized by elemental analysis, X-ray crystal structure analysis, and variable temperature magnetic susceptibility and ESR spectrum measurements. A fairly large antiferromagnetic interaction (J = −130 cm−1) between the diruthenium core and the nitroxide radical has been observed.
  • Marko Zupan, Jernej Iskra, Stojan Stavber
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1655-1660
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Hydroxy-substituted organic molecules were used as target molecules in investigations of the role of the reagent structure on the reactivity of three types of N–F class fluorinating reagents: 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) F-TEDA (1a), N-fluorobis(phenylsulfonyl)amine NSF (1b), and N-fluoropyridinium heptafluorodiborate–pyridine (1/1) NFP (1c). Methanol is stable, but hydroquinone is very quickly transformed in acetonitrile to quinone with F-TEDA at room temperature; on the other hand, NSF is less reactive, while oxidation with NFP is achieved only at an elevated temperature; a structure variation of the hydroquinone derivatives did not influence oxidation. Fluorination was achieved with monohydroxy-substituted aromatic compounds; a similar trend concerning the reactivity of N–F reagent (1) was also observed in reactions with 1- and 2-naphthol, while 9-phenanthrol gave 10,10-difluoro-9-(10H)-phenanthrenone with F-TEDA in acetonitrile and 9,10-phenanthrenequinone with NSF. Dealkylation was observed in a reaction with 4-methoxyphenol; although the thio analogue gave bis(4-methoxyphenyl) disulfide, the reactivity was changed and NSF was more reactive than F-TEDA and NFP.
  • Toshiyuki Urano, Hideki Nagasaka, Masaaki Tsuchiyama, Shigeki Shimizu, ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1661-1668
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The sensitization mechanisms of two systems of ketocoumarin dyes with a radical-generating reagent (10,10′-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]benzopyrano [6,7,8-ij]quinolizin-11-one] (KCD-J), 3,3′-carbonylbis]7-(diethylamino)coumarin] (KCD-DA) with 3,3′,4,4′-tetrakis(t-butyldioxycarbonyl)benzophenone (I) in poly(methylmethacrylate) film) and of two systems of coumarin dyes (10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one (CD-J), 3-(2-benzothiazolyl)-7-(diethylamino)coumarin (CD-DA) with I in the film) have been investigated by laser flash photolysis using a total-reflection cell. The fluorescence of the dyes was efficiently quenched by I with static quenching distances of 8.1, 8.6, 15.0, and 10.9 Å for KCD-J, KCD-DA, CD-J, and CD-DA. The decay time of the triplet was moderately quenched by I with a quenching rate (kq) of 5.8 × 105 mol−1 dm3 s−1 for KCD-DA, and slightly with a kq of less than 1 × 105 mol−1 dm3 s−1 for KCD-J; none of the triplet was detected on CD-J and CD-DA. These results suggested that a static sensitization from the fluorescent-excited dyes to I is predominant in photoinitiation systems.
  • Noritaka Ohtani, Yukihiko Inoue, Yuichi Inagaki, Kenji Fukuda, Taisuke ...
    1995 年 68 巻 6 号 p. 1669-1675
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The reactions of alanine decyl ester (AlaODc) with nucleophiles were catalyzed by a crosslinked polystyrene-supported ethylenediamine–copper(II) ion complex (Cu en-PS) under toluene/resin two-phase conditions or toluene/aqueous buffer/resin three-phase conditions. In the two-phase reactions with octylamine, the rate was increased with a decreasing metal content of the resin. The catalytic efficiency was also dependent on other factors, that is, metal ion, ligand structure, and substrate structure. In the three-phase reactions with water, the hydrolysis was very fast when acetate ions were present in the aqueous phase. It has been suggested that the reactions proceed via a substrate-coordinated intermediate complex under both conditions.
  • Soichi Uchida, Shintaro Yamada, Yasushi Yokoyama, Yukio Kurita
    1995 年 68 巻 6 号 p. 1677-1682
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Photochromic fulgides with a bulky 1-alkyl-1-indolylmethylidene and/or a bulky alkylidene substituent were synthesized and their photochromic as well as absorption spectroscopic properties were compared with those of the known prototype indolylfulgide, 3-[1-(1,2-dimethyl-3-indolyl)ethylidene]-4-isopropylidenedihydro-2,5-furandione. An increase in steric bulkiness of the alkyl group (R1) on the indolylmethylidene group increased the coloring quantum yield (ΦEC = 0.046 (R1 = methyl) to 0.31 (R1 = isopropyl)), whereas an increase in the steric bulkiness of the other alkylidene group (R2) increased the bleaching quantum yield (ΦCE = 0.051 (R2 = isopropylidene) to 0.42 (R2 = 2-adamantylidene)). When both R1 and R2 were bulky, however, the coloring quantum yield was not large, although the bleaching quantum yield was still large. When the methyl group on the 2-position of the indole ring was substituted with an ethyl group, the absorption maximum of the colored form showed a 32-nm bathochromic shift.
  • Michiharu Mitani, Takahiro Sudoh, Kikuhiko Koyama
    1995 年 68 巻 6 号 p. 1683-1687
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    When dimethyl acetylenedicarboxylate is reacted with ketene alkyl trimethylsilyl acetals in the presence of a catalytic amount of zirconium tetrachloride, dimethyl 2-alkoxycarbonyl-3-alkylidenebutanedioates are afforded. Although the silyl enol ether from acetophenone undergoes the same type of reaction, other trisubstituted silyl enol ethers such as those from butyrophenone and 3-pentanone fail to react with dimethyl acetylenedicarboxylate under these conditions.
  • Masanari Kimura, Shuji Tanaka, Yoshinao Tamaru
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1689-1705
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Silver(I) salts in combination with an appropriate base (mostly triethylamine) catalyzed the aminocyclization of N-substituted 2,3-butadienyl carbamates 1 (benzene, 50 °C) to provide 4-vinyl-2-oxazolidinones 2 in good yields. The stereoselectivity (trans-2/cis-2) ranged from 1.4 for C5-Me to >30 for C5-phenyl, isopropenyl, and t-butyl derivatives. 3,4-Pentadienyl tosylcarbamates 3, the one-carbon higher homologues of 1, underwent a similar cyclization to give 4-vinyltetrahydro-2H-1,3-oxazin-2-one 4 in synthetically useful yields and in higher trans selectivities than 1.
  • Noriyoshi Arai, Koichi Narasaka
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1707-1714
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The one-electron oxidation of α-(arylazo)triphenylmethanes by cerium(IV) ammonium nitrate (CAN) generated aryl radicals along with the triphenylmethyl cation. When the reaction was carried out in the presence of appropriate radical-trapping agents, such as arenes and olefins, the corresponding addition products were obtained in moderate yield. The oxidation of the arylazo compounds with CAN was accelerated by the addition of acids.
  • Koji Matsuoka, Shin-Ichiro Nishimura, Yuan C. Lee
    1995 年 68 巻 6 号 p. 1715-1720
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    A combination of mercury(II) bromide (HgBr2) and 2,4,6-collidine was found to promote the formation of activated cyclic sugar derivatives such as 1,2-orthoesters and an oxazoline derivative in quantitative yields at room temperature. A slightly hindered skew like conformation of the lactose orthoester derivative was revealed by 1H NMR analysis. It was also suggested that the reaction of a lactose 1,2-orthoester with trimethylsilyl azide proceeded smoothly to give β-lactosyl azide stereoselectively which is a useful intermediate for constructing glycopeptides and neoglycoconjugates.
  • Kazuaki Ishihara, Naoyuki Hanaki, Miyuki Funahashi, Mayumi Miyata, His ...
    1995 年 68 巻 6 号 p. 1721-1730
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Tris(pentafluorophenyl)boron is an efficient, air stable, and water tolerant Lewis acid catalyst for the aldol-type and Michael reactions of silyl enol ethers with carbonyl compounds or other electrophiles (trimethyl orthoformate, dimethyl acetal, and chloromethyl methyl ether), the allylation reaction of allylsilanes with aldehydes, and the Diels–Alder reaction of dienes with α,β-unsaturated aldehydes. A solution of formaldehyde in water is applicable as an electrophile. Also, the aldol-type reaction of ketene silyl acetals with aromatic or aliphatic imines is successfully carried out using the same catalyst.
  • Hiroshi Miyauchi, Toshio Nakamura, Naohito Ohashi
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1731-1737
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Threo-2-aryl-2-[1-(methylthio)ethyl]oxiranes (1ad) were reacted with acetic acid to give two types of unexpected ring-opening products, threo-1-acetoxy-2-aryl-3-methylthio-2-butanols (4ad) and mono-O-acetyl derivatives of threo-2-aryl-2-methylthio-1,3-butanediol (5ad and 6ad). On the other hand, erythro-2-aryl-2-[1-(methylthio)ethyl]oxiranes (2ad) gave erythro-1-acetoxy-2-aryl-3-methylthio-2-butanols (7ad) and mono-O-acetyl derivatives of erythro-2-aryl-2-methylthio-1,3-butanediol (8ad and 9ad). It is suggested that these products are generated from thiiranium ionic intermediates, because they all completely retain the relative configuration of the starting oxiranes.
  • Koichi Eguchi, Mitsunori Watabe, Shigeki Ogata, Hiromichi Arai
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1739-1745
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    The removal of NO by absorption in manganese zirconium oxide (Mn–Zr oxide) was investigated in both the presence and absence of gaseous O2. The Mn–Zr oxide at Mn/Zr = 1 exhibited a high NO absorption rate and capacity at 200 °C. The absorption was promoted in the presence of O2. The absorption capacity was not strongly affected by the NO concentration (75—900 ppm) and W/F (0.125—1 g s cm−3). An infrared analysis of the absorbed species indicated that the absorption proceeds as the formation of nitrate in the bulk solid. The absorption and desorption were reversible, and the oxide solid was recovered upon heating a preabsorbed sample at 400 °C. Although the amorphous phase of the Mn–Zr oxide which is formed after heating at 450 °C is effective for NO absorption, due to good mixing of manganese oxide and zirconium oxide, heating at higher temperatures (≥550 °C), leading to a decrease in the surface area and crystallization of single oxides, resulted in a decrease in the absorption capacity. NO removal appears to proceed by the oxidation of NO on the Mn sites, and a subsequent absorption at the Zr sites as (NO3) species.
  • Miki Mori, Toshihiro Nakai, Hidenori Yahiro, Masahiro Nitta, Kazuo Sas ...
    原稿種別: Accounts
    専門分野: AI
    1995 年 68 巻 6 号 p. 1747-1751
    発行日: 1995年
    公開日: 2006/07/07
    ジャーナル 認証あり
    Phenol is readily produced by some stoichiometric reactions of benzene with certain copper(II) salts. The main part of the reaction using copper(II) sulfate is estimated to be expressed by the following equation:

    This reaction was carried out in a flow system at 300 °C, where a vapor mixture of benzene and water flowed through a packed bed of copper(II) sulfate supported on silica gel. The products were mainly phenol and CO2 with a trace amount of biphenyl. The phenol yield became appreciable at temperatures higher than 250 °C, and reached a maximum at ca. 300 °C. At higher temperatures, the CO2 yield increased along with the consumption of phenol. The percentage yield of phenol based on copper(II) salt was 86% at the highest. Although copper(II) phosphate was similarly useful, it required a higher reaction temperature (ca. 500 °C).
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