2025/02/27 更新

写真a

セキネ　アキコ
関根　あき子
SEKINE AKIKO
所属
理学院 助教
職名
助教
外部リンク

学位

  • 博士(理学) （ 東京工業大学 ）

研究キーワード

  • X線結晶化学、結晶相光反応、フォトクロミズム

研究分野

  • ナノテク・材料 / 基礎物理化学

所属学協会

委員歴

  • 日本化学会   トピックス委員  

    1997年 - 2001年   

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    団体区分：学協会

    日本化学会

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MISC

  • Control of photochemical, photophysical, electrochemical, and photocatalytic properties of rhenium(I) complexes using intramolecular weak interactions between ligands

    H Tsubaki, A Sekine, Y Ohashi, K Koike, H Takeda, O Ishitani

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   127 ( 44 )   15544 - 15555   2005年11月

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    記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

    Intramolecular interactions between ligands have been successfully applied as a novel tool for controlling various properties of a series of cis, trans- [Re(dmb) (CO)(2) (PR3) (PR'(3))](+)-type complexes (dmb = 4,4'-dimethyl-2,2'-bipyridine), in the ground state and in the excited state and in the one-electron reduced form. For rhenium complexes with two triarylphosphine ligands, P(p-XPh)3, the dmb ligand was sandwiched by four aryl rings having CH(aryl)-pi(pyridine)-pi(aryl) interactions. On the other hand, complexes with one triarylphosphine ligand and one trialkylphosphite ligand, P(OR)(3), had pi-pi and CH-pi interactions between each pyridine ring in the dmb ligand and the aryl group in the P(p-XPh)(3), Various properties of these two series of rhenium complexes were compared with those of complexes having two trialkylphosphite ligands, which do not interact through space with the dmb ligand. Properties of the complexes associated mainly with the dmb ligand are strongly affected by the intramolecular interactions: (1) UV/vis absorptions to the pi-pi* and (MLCT)-M-1 excited states were both red-shifted, but (2) emission from the (MLCT)-M-3 excited state was blue-shifted; (3) the lifetime of the 3MLCT excited state was prolonged up to 3-fold; (4) the reduction potential in the ground state was positively shifted by 110 mV with pi-pi and CH -pi interactions and by 180-200 mV with the CH-pi-pi interactions. (5) In the excited states, the oxidation power of the complex was also enhanced by the intramolecular interactions. (6) In the corresponding one-electron-reduced species cis, trans-[Re(dmb(-.))(CO)(2)(PR3)(PR'(3))], the intramolecular interactions are maintained and strongly affected their UV/vis spectra. (7) Photocatalysis for CO2 reduction was significantly enhanced only by the CH-pi-pi interaction.

    DOI： 10.1021/ja053814u

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  • X-ray analysis of bond elongation in VO(acac) 2 at the excited state

    Manabu Hoshino, Akiko Sekine, Hidehiro Uekusa, Yuji Ohashi

    Chemistry Letters   34 ( 9 )   1228 - 1229   2005年9月

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    記述言語：英語  

    X-ray crystal structural analysis of bis(acetylacetonato) oxovanadium(IV), VO(acac) 2, complex with photoirradiation at low temperatures clearly indicated the structural distortion caused by the production of the excited molecules with the elongated V=O and V-O bonds in the crystalline lattice. Copyright © 2005 The Chemical Society of Japan.

    DOI： 10.1246/cl.2005.1228

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  • Modified photoreactivity due to mixed crystal formation. III. Decelerated photoisomerization upon topochemically unfavorable conformational change

    C Vithana, H Uekusa, A Sekine, Y Ohashi

    CRYSTAL GROWTH & DESIGN   5 ( 5 )   1755 - 1760   2005年9月

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    記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

    The cobaloxime complexes of (2-cyanoethyl)(aniline)dimethylglyoximatocobalt(III) and (2-cyanopropyl)(aniline)dimethylglyoximatocobalt(III) formed mixed crystals with (4-cyanobutyl)(aniline)dimethylglyoximatocobalt(III), Mix-I and Mix-II, respectively, although the component molecules have considerably different structures. The conformations of Co-C-C-CN of the 2-cyanoethyl and 2-cyanopropyl groups in the respective pure crystals are gauche, but they changed to trans in the mixed crystals. Because the conformations of Co-C-C-C and C-C-C-CN of the 4-cyanobutyl group are trans in both the pure crystal and the mixed crystals, structural mimicry or conformational adoption occurred at the Co-C-C-CN group of each minor component in the mixed crystal formation. The 2-cyanoethyl and 2-cyanopropyl groups of the cobaloxime complexes were isomerized to 1-cyanoethyl and 1-cyanopropyl groups on exposure to a xenon lamp. The isomerization rates were estimated from the changes of the FT/IR spectra. The rate constants of the two groups in both pure crystals and mixed crystals were calculated assuming first-order kinetics. Since the conformations of the reactive 2-cyanoethyl and 2-cyanopropyl groups were changed to topochemically unfavorable trans conformations on mixed crystal formation, the rate constants of isomerization of the 2-cyanoethyl and 2-cyanopropyl groups in the Mix-I and Mix-II crystals, were reduced to about one-third and one-fourth of the original values, respectively, compared to the corresponding rates in the pure crystals.

    DOI： 10.1021/cg0495633

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  • Transition metal complexes coordinated by an NAD(P)H model compound and their enhanced hydride-donating abilities in the presence of a base

    A Kobayashi, H Konno, K Sakamoto, A Sekine, Y Ohashi, M Iida, O Ishitani

    CHEMISTRY-A EUROPEAN JOURNAL   11 ( 14 )   4219 - 4226   2005年7月

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    記述言語：英語   出版者・発行元：WILEY-V C H VERLAG GMBH  

    The ruthenium(II) and thenium(I) complexes containing an NAD(P)H model compound, 1-benzyl-1,4-dihydronicotinamide (BNAH), as ligand, [Ru(tpy)(bpy)(BNAH)](2+) (1a) and [Re(bpy)(CO)(3)(BNAH)](+) (1b), were quantitatively produced by the reaction of the corresponding metal hydrido complexes with BNA(+) (1-benzylnicotinamidium cation). In the presence of base with pK(a) = 8.9, 1a and 1b have much greater reducing power than "free" BNAH. The oxidation potentials of la in the absence and the presence of triethylamine were 0.55V and -0.04V, respectively, versus Ag/ AgNO3, whereas that of "free" BNAH was 0.30V Spectroscopic results clearly showed that the base extracts a proton from the carbamoyl group on 1a and 1b to give the deprotonated BNAH coordinating to the transition-metal ;complexes [Ru(tpy)(bpy)(BNAH-H+)](+) (3 a) and [Re(bpy)(CO)(3)(BNAH-H+)] (3b); this deprotonation underlies the enhancement in reducing ability. The deprotonated forms 3a and 3b can efficiently reduce other NAD(P) models to give the corresponding 1,4-dihydro form, resulting in the deprotonated BNA(+) being coordinated to the metal complexes [Ru(tpy)(bpy)(BNA(+)-H+)](2+) (2a) and [Re(bpy)(CO)(3)(BNA(+)-H+)](+) (2b); "free" BNAH and the protonated adducts la and 1b cannot act in this way. X-ray crystallography was performed on the PF6- salt of 2a, and showed that the deprotonated nitrogen atom on the carbamoyl group coordinates to the ruthenium(II) metal center with a bond length of 2.086(3) angstrom. Infrared spectral data suggested that the deprotonated carbamoyl group on the reduced forms 3a and 3b is converted to the imido group, and that the oxygen atom coordinates to the metal center.

    DOI： 10.1002/chem.200401211

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  • X-ray Analysis of Bond Elongation in Vo(acac)2 at the Excited State

    Manabu Hoshino Akiko Sekine, Hidehiro Uekusa, Yuji Ohashi

    Chem. Lett.   34 ( 9 )   1228 - 1229   2005年

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  • Physicochemical and Crystal Structure Analyses of the Antidiabestic Agent Troglitazone

    Katsuhiro Kobayashi, Hiroshi Fukuda Akiko Sekine Hidehiro Uekusa Yuji Ohashi

    Chem. Pharm. Bull.   51 ( 7 )   807 - 814   2003年

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  • Physicochemical and Crystal Structure Analyses of the Antidiabestic Agent Troglitazone

    Katsuhiro Kobayashi, Hiroshi Fukuda Akiko Sekine Hidehiro Uekusa Yuji Ohashi

    Chem. Pharm. Bull.   51 ( 7 )   807 - 814   2003年

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  • Structure of the photocolored 2-(2 ',4 '-dinitrobenzyl)pyridine crystal: Two-photon induced solid-state proton transfer with minor structural perturbation

    P Naumov, A Sekine, H Uekusa, Y Ohashi

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   124 ( 29 )   8540 - 8541   2002年7月

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    記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

    DOI： 10.1021/ja0170908

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  • Modified photoreactivity due to mixed crystal formation. I. Three mixed crystals between isostructural cobaloxime complexes

    C Vithana, H Uekusa, A Sekine, Y Ohashi

    ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE   58   227 - 232   2002年4月

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    記述言語：英語   出版者・発行元：BLACKWELL MUNKSGAARD  

    Three crystals of 2-cyanoethyl cobaloxime complexes with 3-chloropyridine, 3-bromopyridine and 3-methylpyridine as axial base ligands are isostructural to one another. Three mixed crystals were formed between the pairs: (3-bromopyridine)(2-cyanoethyl)cobaloxime-(2-cyanoethyl)(3-methyl- pyridine)cobaloxime (0.45/0.55); (3-chloropyridine)(2-cyanoethyl) cobaloxime-( 2-cyanoethyl) (3-bromopyridine)cobaloxime (0.61/0.39); (3-chloropyridine)(2-cyanoethyl)cobaloxime- (2-cyanoethyl)(3-methylpyridine)cobaloxime (0.44/0.56). The X-ray crystal structure analysis revealed that the mixed compounds are also isostructural to the component crystals. It was found from the change in IR spectra that the 2-cyanoethyl groups in the three mixed crystals isomerized to 1-cyanoethyl groups on exposure to a xenon lamp, as observed for the 2-cyanoethyl groups in the component crystals. Rate constants for the three mixed and three component crystals, measured under the same conditions, are approximately the same, as the reaction cavities for the 2-cyanoethyl groups in the six crystals have almost the same size. For the mixed crystal between 3-chloropyridine and 3-methylpyridine complexes, the isomerization proceeded with retention of the single-crystal form. The conformation and configuration of the 1-cyanoethyl group that was produced were well explained by the shape of the reaction cavity before irradiation.

    DOI： 10.1107/S0108768101019346

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  • Modified Photoreactivity due to Mixed Crystal Formation. II. Enhanced reactivity upon Conformational Mimicry and Cavity Enlargement

    Champika Vithana Hidehiro Uekusa Akiko Sekine, Yuji Ohashi

    Acta Cryst. B.   58   227 - 232   2002年

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  • Modified Photoreactivity due to Mixed Crystal Formation. II. Enhanced reactivity upon Conformational Mimicry and Cavity Enlargement

    Champika Vithana Hidehiro Uekusa Akiko Sekine, Yuji Ohashi

    Acta Cryst. B.   58   227 - 232   2002年

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  • Energy-transfer rate in crystals of double-complex salts composed of [RU(N-N)(3)](2+) (N-N=2,2 '-bipyridine or 1,10-phenanthroline) and [Cr(CN)(6)](3-): Effect of relative orientation between donor and acceptor

    T Otsuka, A Sekine, N Fujigasaki, Y Ohashi, Y Kaizu

    INORGANIC CHEMISTRY   40 ( 14 )   3406 - 3412   2001年7月

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    記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

    A block single-crystal was obtained using a diffusion method with a concentrated acetone-water(vol. 1/1) solution of [Ru(phen)(3)]Cl-2. 6H(2)O (phen = 1,10-phenanthroline) and a concentrated aqueous solution of K-3[Cr(CN)(6)], without evaporating solvents. The crystal was identified as a double-complex salt including two acetone and fourteen solvent water molecules, [Ru(phen)(3)](2)[Cr(CN)(6)]Cl .2(CH3)(2)CO . 14H(2)O (1). Measurement of the X-ray diffraction pattern of the double-complex salt was performed using an X-ray diffractometer with an Imaging-Flare (IP) Weissenberg camera. 1 crystallizes in the triclinic space group P (1) over bar, with a = 13.930(5) Angstrom, b = 14.783(5) Angstrom, c = 11.137(6) Angstrom, alpha = 89.87(4)degrees, beta = 107.47(3)degrees gamma = 96.68(3)degrees, and Z = 2. The crystal structure is very different from that of [Ru(bpy)(3)](2)[Cr(CN)(6)]Cl . 8H(2)O (2) (bpy = 2,2 ' -bipyridine), which could be obtained using the same procedure and crystallizes in the monoclinic space group C2, with a = 22.414(2) Angstrom, b = 13.7686(15) Angstrom, c = 22.207(2) Angstrom, beta = 90.713(8)degrees, and Z = 4. The distance between the central-metal ions of ruthenium(II) and chromium(III) complexes in [Ru(phen)(3)](2)[Cr(CN)(6)]Cl .2(CH3)(2)CO . 14H(2)O (7.170 Angstrom) is shorter than that in [Ru(bPY)(3)](2)[Cr(CN)(6)]Cl . 8H(2)O (9.173 Angstrom) by about 2 Angstrom, while the rate of energy transfer from the (MLCT)-M-3 state of [Ru(N-N)(3)](2+) to the E-2(g) state of [Cr(CN)(6)](3-) in the former salt (9.5 x 10(5) s(-1)) is far slower than that in the latter one (6.0 x 10(6) s(-1)) at 77 K. These results indicate that the energy-transfer rate strongly depends, not upon the distance between central metal ions, rather, upon the mutual relative orientation between the donor and the acceptor complexes in double-complex salts.

    DOI： 10.1021/ic0013936

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  • Platinum-Catalyzed Bis-Germylation of Alkynes with Organodigermanes and Cyclic Oligogermanes

    AKIKO SEKINE

    Bull. Chem. Soc. Jpn.   74 ( 1 )   123 - 137   2001年

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  • Platinum-Catalyzed Bis-Germylation of Alkynes with Organodigermanes and Cyclic Oligogermanes

    AKIKO SEKINE

    Bull. Chem. Soc. Jpn.   74 ( 1 )   123 - 137   2001年

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  • Pressure-induced Structural Change of the tetrafluoro-p-benzoquinone(p-fluoranil) from ab initio Total Calculations

    Fabio Pichierri Akiko Sekine, Toshikazu Ebisuzaki

    Chem. Phys.   264 ( 1 )   9 - 19   2001年

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  • Pressure-induced Structural Change of the tetrafluoro-p-benzoquinone(p-fluoranil) from ab initio Total Calculations

    Fabio Pichierri Akiko Sekine, Toshikazu Ebisuzaki

    Chem. Phys.   264 ( 1 )   9 - 19   2001年

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  • Synthesis of 2-Fluoro Analogues of Frontalin

    Pierfrancesco Bravo, Massimo Frigerio, Taizo Ono Walter, Panzeri Cristina, Pesenti Akiko Sekine, Fiorenza Viani

    Eur. J. Org. Chem.   ( 8 )   1387 - 1389   2000年

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  • Synthesis of 2-Fluoro Analogues of Frontalin

    Pierfrancesco Bravo, Massimo Frigerio, Taizo Ono Walter, Panzeri Cristina, Pesenti Akiko Sekine, Fiorenza Viani

    Eur. J. Org. Chem.   ( 8 )   1387 - 1389   2000年

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  • Structure of NG-061, a novel potentiator of nerve growth factor (NGF) isolated from Penicillium minioluteum F-4627

    R Bhandari, T Eguchi, A Sekine, Y Ohashi, K Kakinuma, M Ito, K Mizoue

    JOURNAL OF ANTIBIOTICS   52 ( 3 )   231 - 234   1999年3月

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    記述言語：英語   出版者・発行元：JAPAN ANTIBIOT RES ASSN  

    The structure of NG-061. a new potentiator of nerve growth factor (NGF) isolated from Penicillium minioluteum F-4627, was determined by spectroscopic analysis and X-ray diffraction method to be phenylacetic acid 2-(2-methoxy-4-oxocyclohexa-2,4-dienylidene)-hydrazide.

    DOI： 10.7164/antibiotics.52.231

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  • Stereoselective synthesis of enantiomerically pure beta-fluoroalkyl gamma-butyrolactones by sulfoxide-directed lactonization

    P Bravo, A Arnone, P Bandiera, L Bruche, Y Ohashi, T Ono, A Sekine, M Zanda

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY   ( 1 )   111 - 115   1999年1月

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    記述言語：英語   出版者・発行元：WILEY-V C H VERLAG GMBH  

    Enantiomerically pure alpha,alpha-dichloro beta-fluoroalkyl gamma-p-tolylthio gamma-butyrolactones trans-6a-c have been obtained with excellent stereocontrol (> 98:2) and enantiomeric purity (> 98:2) by sulfoxide-directed lactonization (Marino's annulation reaction) of beta-fluoroalkyl vinyl sulfoxides (R)-(E)-5a-c with dichloroketene. Highly chemoselective dechlorination and desulfurization reactions performed on trans-6c efficiently provided the beta-chlorodifluoromethyl gamma-butyrolactone (S)-8c, the absolute stereochemistry of which was determined by X-ray diffraction analysis of its gamma-p-tolylthio precursor (2R,3S)-7c.

    DOI： 10.1002/(SICI)1099-0690(199901)1999:1<111::AID-EJOC111>3.3.CO;2-X

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  • Crystal Structure and Energy Transfer in Double-Complex Salts Composed of Tris(2,2'-bipyridine)ruthenium(II) or Tris(2,2'-bipyridine)osmium(II) and Hexacyanochromate(III)

    AKIKO SEKINE

    Inorg. Chem.   38 ( 6 )   1340 - 1347   1999年

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  • Crystal Structure and Energy Transfer in Double-Complex Salts Composed of Tris(2,2'-bipyridine)ruthenium(II) or Tris(2,2'-bipyridine)osmium(II) and Hexacyanochromate(III)

    AKIKO SEKINE

    Inorg. Chem.   38 ( 6 )   1340 - 1347   1999年

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  • Synthesis and photochemistry of 1,2-digermacyclohexa-3,5-dienes and related compounds

    K Mochida, M Akazawa, M Goto, A Sekine, Y Ohashi, Y Nakadaira

    ORGANOMETALLICS   17 ( 9 )   1782 - 1789   1998年4月

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    記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

    Some new germanium analogues of 1,3-cyclohexadiene,3,4,5,6-tetraphenyl-, 3,6-diphenyl-, and 3,4,5,6-tetramethyl-1,2-digermacyclohexa-3,5-diene and 3,4,5,6-tetraphenyl-1-germa-2-silacyclohexa-3,5-diene, were prepared and fully characterized by spectroscopic methods. On photolysis, the 1,2-digermacyclohexa-3,5-diene underwent extrusion of dialkylgermylene (R2Ge:) to give the corresponding germacyclopentadiene. On irradiation the 1-germa-2-silacyclohexa-3,5-diene yielded preferentially the silacyclopentadiene via extrusion of R2Ge:. The mechanism of these photolyses is discussed.

    DOI： 10.1021/om970799w

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  • Thermal Ring Contraction of 1,2-Digermacyclohexadienes Coordinated with Iron Tricarbonyl Fragment(共著)

    Kunio Mochida, Wakako, Hatanaka Tohru, Wada Akiko Sekine, Yuji Ohashi Akio Yamamoto

    Chemistry Letters   ( 10 )   991 - 992   1998年

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  • Crystallire-State Racemization of Cobaloxime Complex.XX.Cooperrative Motion of Solvent Molecule.

    AKIKO SEKINE

    Enantiomer   ( 3 )   159 - 168   1998年

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  • Thermal Ring Contraction of 1,2-Digermacyclohexadienes Coordinated with Iron Tricarbonyl Fragment(共著)

    Kunio Mochida, Wakako, Hatanaka Tohru, Wada Akiko Sekine, Yuji Ohashi Akio Yamamoto

    Chemistry Letters   ( 10 )   991 - 992   1998年

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  • Crystalline-state racemization of cobaloxime complex. XX. Cooperative motion of solvent molecule

    A Sekine, M Saitoh, D Hashizume, H Uekusa, Y Ohashi, Y Arai, Y Ohgo

    ENANTIOMER   3 ( 2 )   159 - 168   1998年

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    記述言語：英語   出版者・発行元：GORDON BREACH SCI PUBL LTD  

    The chiral 1-methoxycarbonylethyl group bonded to the cobalt atom in the crystal of [(R)-1-methoxycarbonylethyl] (cyclohexylamine)bis(dimethyl-glyoximato)- cobalt(III) benzene solvate is racemized on exposure to a xenon lamp with retention of the single crystal form at room temperature. The crystal structures before irradiation, after 230 h exposure and after 600 h exposure were determined by X-rays. The two crystallographically independent molecules, A and B, in the P2(1) cell before irradiation are related by a pseudo inversion. On exposure to visible light, the unit-cell dimensions gradually changed and the pseudo inversion center becomes a crystallographic one. The chiral methoxycarbonylethyl (mce) group of the B molecule is inverted to the opposite configuration whereas the mce group of A remains unaltered. The solvent benzene molecule occupies between the two mce groups of A and B and lies on a pseudo inversion center and cooperatively moves in the process of the racemization. Finally it occupies the crystallographic inversion center between the two mce groups. The crystal after 600 h exposure has a different structure from that produced from a benzene methanol solution with the racemic compounds.

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  • Synthesis and Photochemistry of 1,2-Digermacyclohexa-3,5-dienes and Related Compounds(共著)

    AKIKO SEKINE

    Organometallics   17 ( 9 )   1782 - 1789   1998年

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  • X-Ray Analyses of Complexes Formed between Surfactants and Aromatic Coumpounds, I. A Common Structural Pattern of the Complexes(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   71 ( 9 )   2109 - 2118   1998年

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  • X-ray Analysis of Successive Reaction in Crystalline State Photoisomerization of Cobaloxime Complexes

    Akiko Sekine, Mizuho Yoshiike, Yuji Ohashi, Kanako Ishida, Yoshifusa Arai, Yoshiaki Ohgo

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS   313   321 - 326   1998年

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    記述言語：英語   出版者・発行元：GORDON BREACH PUBLISHING, TAYLOR & FRANCIS GROUP  

    The -cyanopropyl group bonded to the cobalt atom in some cobaloxime complexes was isomerized to the -cyanopropyl group through -cyanopropyl group on exposure to visible light in the solid state. For the complex with 1-phenylethylamine as an axial base ligand almost chiral -cyanopropyl group was produced with retention of the single crystal form. The mechanism is discussed on the basis of the structural change.

    DOI： 10.1080/10587259808044294

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  • Synthesis and Photochemistry of 1,2-Digermacyclohexa-3,5-dienes and Related Compounds(共著)

    AKIKO SEKINE

    Organometallics   17 ( 9 )   1782 - 1789   1998年

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  • Crystalline-State Racemization of Cobaloxime Complex, XX. Cooperarive Motion of Solvent Molecule

    AKIKO SEKINE

    Enantiomer   3   159 - 168   1998年

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  • Crystallire-State Racemization of Cobaloxime Complex.XX.Cooperrative Motion of Solvent Molecule.

    AKIKO SEKINE

    Enantiomer   ( 3 )   159 - 168   1998年

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  • X-Ray Analyses of Complexes Formed between Surfactants and Aromatic Coumpounds, I. A Common Structural Pattern of the Complexes(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   71 ( 9 )   2109 - 2118   1998年

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  • Crystalline-state β-α photoisomerization of cobaloxime complexes, part 1 generation of asymmetry in chiral crystal environment

    Akiko Sekine, Hiroaki Tatsuki, Yuji Ohashi

    Journal of Organometallic Chemistry   536-537 ( 1/2 )   389 - 398   1997年5月

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    記述言語：英語   出版者・発行元：Elsevier  

    The β-cyanoethyl groups bonded to the cobalt atoms in [β-cyanoethyl](3-methylpyridine)bis(dimethylglyoximato)cobalt(III) and [β-cyanoethyl](4-methylpyridine)bis(dimethylglyoximato)cobalt(III) are isomerized to the α-cyanoethyl groups, at room temperature and at 346 K respectively, on exposure to visible light with retention of the single crystal form. The produced α-cyanoethyl group has a chiral carbon atom bonded to the cobalt atom. The crystal structures of the 3-methylpyridine complex before and after the irradiation, which were determined by X-rays, revealed that the ratio of the R and S configurations of the produced α-cyanoethyl group in one site was not 1:1 but about 4:7. On the other hand, the α-cyanoethyl group only had the R configuration in one site of the 4-methylpyridine complex crystal. The difference in shape of the reaction cavities for the produced α-cyanoethyl groups of the two complex crystals well explains the reason why such different degrees of asymmetry were generated in the produced α-cyanoethyl groups. © 1997 Published by Elsevier Science S.A.

    DOI： 10.1016/S0022-328X(96)06742-3

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  • Crystalline-state β-α photoisomerization of cobaloxime complexes, part 1 Generation of asymmetry in chiral crystal environment

    AKIKO SEKINE

    Journal of Organometallic Chemistry   536 ( 1-2 )   389 - 398   1997年5月

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  • Quantitative comparison of Photoisomerization of three cobaloxime complexes in the solid and crystalline states

    AKIKO SEKINE

    Journal of Molecular Structure   374 ( 1-3 )   269   1996年

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  • Generation of Chirality in Crystalline-state Isomerization of Cobaloxime Complexes(共著)

    AKIKO SEKINE

    Molecular Crystal and Liquid Crystal   277   1 - 10   1996年

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  • Quantitative comparison of photoisomerization of three cobaloxime complexes in the solid state and crystalline state

    AKIKO SEKINE

    Journal of Molecular Structure   374 ( 1-3 )   269   1996年

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  • β-α Photoisomerization of Cobaloxime Complexes in the Solid State. 5. Reaction Rate Reduced by a Hydrogen Bond

    Hiroki Amano, Akiko Sekine, Yuji Ohashi, Mieko Hagiwara, Junko Sato, Yoshifusa Arai, Yoshiaki Ohgo

    Bulletin of the Chemical Society of Japan   69 ( 11 )   3107 - 3114   1996年

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    記述言語：英語   出版者・発行元：Chemical Society of Japan  

    The crystal structures of three cobaloxime complexes with different axial base ligands have been analyzed by X-ray analysis at room temperature. I: (2-Cyanoethyl)bis(dimethylglyoximato)((S)-phenylalaninol)cobalt(III)
    the crystal is orthorhombic, the space group being P212121, Z = 4 with a = 9.416(3), b = 27.184(3), c = 9.184(3) Å. II: (2-Cyanoethyl)-bis(dimethylglyoximato)((S)-phenyl-alanine methyl ester)cobalt(III)
    the crystal is monoclinic, the space group being P21, Z = 4 with a = 14.376(2), b = 11.988(2), c = 14.874(1) Å, and β = 101.05(1)°. III: (2-Cyanoethyl)bis(dimethylglyoximato)-(methyldiphenylphosphine)cobalt(III)
    the crystal is monoclinic, the space group being P21/n, Z = 4 with a = 11.558(4), b = 15.542(3), c = 14.393(5) Å, and β = 91.02(4)°. The structures were refined by the full-matrix least-squares method to final R values of 0.041, 0.052, and 0.044 for 2340, 3287, and 4400 observed reflections, respectively. The photoisomerization rates of I, II, and III in the solid state were obtained from the changes in the IR spectra. The rate of I was insignificantly small, but the rates of II and III were calculated to be 0.1 x 10-4 and 1.9 x 10-4 s-1, respectively, assuming first-order kinetics. The 2-cyanoethyl groups in the three complex crystals take perpendicular conformations to their cobaloxime planes. The 2-cyanoethyl group of I makes a hydrogen bond with the N-H group of the neighboring molecule. The non-reactivity of I may be brought about by the hydrogen bond.

    DOI： 10.1246/bcsj.69.3107

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  • Four Polymorphs of a cobaloxime complex with different solid-state photoisomerization rates(共著)

    AKIKO SEKINE

    Acta Crystallographica Section B   52 ( 2 )   303 - 313   1996年

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  • β-α Photoisomerization of Cobaloxime Complexes in the Solid State. 5. Reaction Rate Reduced by a Hydrogen Bond(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   69 ( 11 )   3107 - 3114   1996年

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  • Quantitative comparison of photoisomerization of three cobaloxime complexes in the solid state and crystalline state

    AKIKO SEKINE

    Journal of Molecular Structure   374 ( 1-3 )   269   1996年

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  • Quantitative comparison of Photoisomerization of three cobaloxime complexes in the solid and crystalline states

    AKIKO SEKINE

    Journal of Molecular Structure   374 ( 1-3 )   269   1996年

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  • Generation of Chirality in Crystalline-state Isomerization of Cobaloxime Complexes(共著)

    AKIKO SEKINE

    Molecular Crystal and Liquid Crystal   277   1 - 10   1996年

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  • Four Polymorphs of a cobaloxime complex with different solid-state photoisomerization rates(共著)

    AKIKO SEKINE

    Acta Crystallographica Section B   52 ( 2 )   303 - 313   1996年

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  • Stereochemistry of Asymmetric β-Lactam Formation Involving Achiral Glyoxylamide Derivatives(共著)

    AKIKO SEKINE

    Acta Crystallographica Section C   51 ( 5 )   929 - 933   1995年

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  • Stereochemistry of Asymmetric β-Lactam Formation Involving Achiral Glyoxylamide Derivatives(共著)

    AKIKO SEKINE

    Acta Crystallographica Section C   51 ( 5 )   929 - 933   1995年

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  • Crystalline-State Reaction of Cobaloxime Complexes. 18. Metastable Intermediate Structure Observed by a New X-Ray Diffractometer for rapid Data Collection(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   68 ( 9 )   2517 - 2525   1995年

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  • Crystalline-State Reaction of Cobaloxime Complexes. 18. Metastable Intermediate Structure Observed by a New X-Ray Diffractometer for rapid Data Collection(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   68 ( 9 )   2517 - 2525   1995年

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  • [(R)-1,2-Diethoxycarbonylethyl]bid(dimethylglyoximato)(methyl-diphenylphosphine)cobalt(III)(共著)

    AKIKO SEKINE

    Acta Crystallographica Section C   51 ( 5 )   828 - 831   1995年

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  • [(R)-1,2-Diethoxycarbonylethyl]bid(dimethylglyoximato)(methyl-diphenylphosphine)cobalt(III)(共著)

    AKIKO SEKINE

    Acta Crystallographica Section C   51 ( 5 )   828 - 831   1995年

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  • 2-NITROBIPHENYL AND 2,2'-DINITROBIPHENYL

    A SEKINE, Y OHASHI, K YOSHIMURA, M YAGI, J HIGUCHI

    ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS   50 ( 7 )   1101 - 1104   1994年7月

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    記述言語：英語   出版者・発行元：MUNKSGAARD INT PUBL LTD  

    2-Nitrobiphenyl, C12H9NO2, and 2,2'-dinitrobiphenyl. C12H8N2O4, are not planar. The molecule of 2,2'-dinitrobiphenyl is located on a crystallographic twofold rotation axis and has C2 symmetry. The dihedral angle between the two phenyl rings [(C1-C6) AND (C7-C12)] and that between the phenyl ring and the nitro group [(C1-C6) AND (N1,O2,O3)] are 63.1 (3) and 44.7 (4)-degrees, respectively, for 2-nitrobiphenyl, and 62.6 (3) and 39.0 (4)-degrees, respectively, for 2,2'-dinitrobiphenyl.

    DOI： 10.1107/S0108270194001009

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  • Lithium Tris(oxalate-O, O')chromate(III)Hexahydrate

    AKIKO SEKINE

    Acta Crystallographica Section C   50 ( 9 )   1399 - 1401   1994年

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  • Chiral Lattice-Controlled Asymmetric Photoisomerization of(2-Cyanoethyl)cobaloximes in the Solid State(共著)

    AKIKO SEKINE

    Chemstry Letters   ( 4 )   715 - 718   1994年

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  • CRYSTALLINE-STATE PHOTOISOMERIZATION AND PHOTOINDUCED PHASE-TRANSITION OF A COBALOXIME COMPLEX

    A SEKINE, H TATSUKI, Y OHASHI

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS   242   109 - 117   1994年

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    記述言語：英語   出版者・発行元：GORDON BREACH SCI PUBL LTD  

    The crystal of (beta-cyanoethyl)bis(dimethylglyoximato)(4-methylpyridine)cobalt(III) exhibits a reversible single crystal-to-single crystal thermal phase transition at 343 K. The beta-cyanoethyl group of the crystal was isomerized to alpha-cyanoethyl group retaining the single crystal form when the crystal was irradiated with a strong Xe lamp above 343 K, although the crystal was decomposed below the temperature. On the other hand, when the crystal was exposed to a weak Xe lamp at 340 K, the crystal showed the phase transition after 20 hours exposure keeping the single crystal form. The crystal after the phase transition also exhibited the beta-alpha photoisomerization on exposure to the strong Xe lamp. The mechanism has clearly been elucidated on the basis of the analyzed structures before and after the photoisomerization or phase transition.

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  • Chiral Lattice-Controlled Asymmetric Photoisomerization of(2-Cyanoethyl)cobaloximes in the Solid State(共著)

    AKIKO SEKINE

    Chemstry Letters   ( 4 )   715 - 718   1994年

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  • Lithium Tris(oxalate-O, O')chromate(III)Hexahydrate

    AKIKO SEKINE

    Acta Crystallographica Section C   50 ( 9 )   1399 - 1401   1994年

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  • The Crystal Water Affecting the ┣D12┫D1Eg-┣D14┫D1A┣D22g┫D2 Relaxation in Tris(oxalato)chromate(III) Complexes(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   65 ( 12 )   3378 - 3385   1992年

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  • The Crystal Water Affecting the ┣D12┫D1Eg-┣D14┫D1A┣D22g┫D2 Relaxation in Tris(oxalato)chromate(III) Complexes(共著)

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   65 ( 12 )   3378 - 3385   1992年

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  • STRUCTURES OF (2-CYANOETHYL)(3-CYANOPYRIDINE)BIS(DIMETHYLGLYOXIMATO(1-)COBALT(III) MONOHYDRATE (I) AND (4-AMINOPYRIDINE)(2-CYANOETHYL)-BIS(DIMETHYLGLYOXIMATO(1-))COBALT(III) (II)

    A SEKINE, Y OHASHI, K HORI

    ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS   47 ( 3 )   525 - 528   1991年3月

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    記述言語：英語   出版者・発行元：MUNKSGAARD INT PUBL LTD  

    (I): [Co(C3H4N)(C4H7N2O2)2(C6H4N2)].H2O, M(r) = 465.35, monoclinic, P2(1)/n, a = 18.425 (4), b = 12.073 (3), c = 10.038 (2) angstrom, beta = 101.95 (2)degrees, V = 2184.1 (4) angstrom3, Z = 4, D(x) = 1.415 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 7.72 cm-1, F(000) = 968, R = 0.061 for 3244 independent reflections. (II): [Co(C3H4N)(C4H7N2O2)2(C5H6N2)], M(r) = 437.34, triclinic, P1BAR, a = 15.347 (5), b = 15.673 (7), c = 8.890 (3) angstrom, alpha = 104.46 (3), beta = 105.74 (3), gamma = 82.38 (5)degrees, V = 1988 (1) angstrom3, Z = 4, D(x) = 1.462 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 8.42 cm-1, F(000) = 912, R = 0.080 for 6448 independent reflections. In each crystal, the 2-cyanoethyl group takes a conformation perpendicular to the cobaloxime plane. The size of the cavity for the 2-cyanoethyl group in crystal (II) is significantly greater than that in crystal (I). This explains the greater isomerization rate of (II) compared with (I) on exposure to visible light.

    DOI： 10.1107/S0108270190009283

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  • Structures of(β-Cyanoethyl)(3-ethylpyridine)bis(dimethyl-glyoximato)cobalt(III)(1)and(β-Cyanoethyl)(4-ethylpyridine)-bis(dimethylglryoximato)cobalt(III)(2)

    AKIKO SEKINE

    Acta Crystallographica Section C   47 ( 1 )   53 - 56   1991年

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  • β-α Photoisomerization of Cobaloxime Complexes in the Solid State III. Accelated Reaction Rate by Hydrogen Bond

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   64 ( 7 )   2183 - 2187   1991年

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  • Structures of(2-Cyanoethyl)(3-cyanopyridine)bis[dimethyl-glyoximato(1-)]cobalt(III)Monohydrate(I)and(4-Amino-pyridine)(2-cyanoethyl)bis[dimethylglyoximato]cobalt(III)(II)

    AKIKO SEKINE

    Acta Crystallographica Section C   47 ( 3 )   525 - 528   1991年

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  • Structures of(β-Cyanoethyl)(3-ethylpyridine)bis(dimethyl-glyoximato)cobalt(III)(1)and(β-Cyanoethyl)(4-ethylpyridine)-bis(dimethylglryoximato)cobalt(III)(2)

    AKIKO SEKINE

    Acta Crystallographica Section C   47 ( 1 )   53 - 56   1991年

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  • β-α Photoisomerization of Cobaloxime Complexes in the Solid State III. Accelated Reaction Rate by Hydrogen Bond

    AKIKO SEKINE

    Bulletin of the Chemical Society of Japan   64 ( 7 )   2183 - 2187   1991年

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  • Three Factors Controlling the Reaction Rate in Solid State Photoisomerization(共著)

    AKIKO SEKINE

    Molecular Crystal and Liquid Crystal   186   37 - 44   1990年

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  • Three Factors Controlling the Reaction Rate in Solid State Photoisomerization(共著)

    AKIKO SEKINE

    Molecular Crystal and Liquid Crystal   186   37 - 44   1990年

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  • X-ray Structual Studies of Chiral β-Lactam Formation from an Achiral Oxo Amide Using the Chiral-Crystal Environment

    AKIKO SEKINE

    the Journal of the American Chemical Society   111   1989年

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  • X-ray Structual Studies of Chiral β-Lactam Formation from an Achiral Oxo Amide Using the Chiral-Crystal Environment

    AKIKO SEKINE

    the Journal of the American Chemical Society   111   1989年

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▼全件表示

受賞

  • 平成7年度 日本結晶学会進歩賞

    1995年  

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    受賞国：日本国

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共同研究・競争的資金等の研究課題

  • Crystalline-State Photoisomerization of Cobaloxime Complexes

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    資金種別：競争的資金

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  • コバロキシム錯体の結晶相光異性化反応

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    資金種別：競争的資金

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