Faculty Profiles - OSHIKI Toshiyuki

Papers - OSHIKI Toshiyuki

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Dramatic rate acceleration by a diphenyl-2-pyridylphosphine ligand in the hydration of nitriles catalyzed by Ru(acac)(2) complexes

T Oshiki, H Yamashita, K Sawada, M Utsunomiya, K Takahashi, K Takai

ORGANOMETALLICS 24 ( 26 ) 6287 - 6290 2005.12

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

New ruthenium(II) complexes having acac (=acetylacetonato) and diphenyl-2-pyridylphosphine as ligands proved to be excellent catalysts for hydration of nitriles to amides under neutral conditions. Among the ruthenium complexes examined, cis-Ru(acac)(2)(PPh(2)py)(2) exhibited the highest activity, with a turnover frequency of up to 20900 (mol of amide)/((mol of catalyst) h).

DOI： 10.1021/om050792b

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A novel heteroligated phenoxy-based titanium complex: Structure, stability, and ethylene polymerization behavior

Y Suzuki, T Oshiki, H Tanaka, K Takai, T Fujita

CHEMISTRY LETTERS 34 ( 10 ) 1458 - 1459 2005.10

Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN

A new phenoxy-imine and phenoxy-ketone heteroligated titanium complex was obtained by hydrolysis of one of the two imine moieties of a bis(phenoxy-imine)Ti complex. X-ray diffraction analysis revealed that the complex assumes an octahedral coordination geometry with a cis-phenoxy-O's and cis-Cl's disposition. NMR studies demonstrated that the complex does not undergo disproportionation. In association with methylaluminoxane, the complex behaved as a non-living-type single-site catalyst for ethylene polymerization.

DOI： 10.1246/cl.2005.1458

Synthesis of bis(phenoxyimine) Ti alkyl complexes and observation of living species by H-1 NMR spectroscopy

H Makio, T Oshiki, K Takai, T Fujita

CHEMISTRY LETTERS 34 ( 10 ) 1382 - 1383 2005.10

Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN

Synthesis of [C6F5N=CH(2-O-C6H3-3-R)](2)TiMex (R: Bu-t; X: Br (2), R: Bu-t; X: Me (3), R: H; X: Me (4)) was achieved by the reaction of methylated titanium halides with sodium salts of the phenoxyimine ligands. These complexes can be activated with equimolar amounts of B(C6F5)(3) or Ph3CB(C6F5)(4) to form methyl cationic species, which, upon addition of a small amount of ethylene monomer allows room temperature observation of cationic polymeryl species.

DOI： 10.1246/cl.2005.1382

Synthesis of bis(phenoxyimine) Ti alkyl complexes and observation of living species by H-1 NMR spectroscopy

H Makio, T Oshiki, K Takai, T Fujita

CHEMISTRY LETTERS 34 ( 10 ) 1382 - 1383 2005.10

Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN

DOI： 10.1246/cl.2005.1382

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A novel heteroligated phenoxy-based titanium complex: Structure, stability, and ethylene polymerization behavior

Y Suzuki, T Oshiki, H Tanaka, K Takai, T Fujita

CHEMISTRY LETTERS 34 ( 10 ) 1458 - 1459 2005.10

Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN

DOI： 10.1246/cl.2005.1458

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Low-temperature catalytic hydrothermal treatment of wood biomass: analysis of liquid products

S Karagoz, T Bhaskar, A Muto, Y Sakata, T Oshiki, T Kishimoto

CHEMICAL ENGINEERING JOURNAL 108 ( 1-2 ) 127 - 137 2005.4

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE SA

Catalytic hydrothermal treatment of wood biomass was performed at 280&DEG; C for 15 min in the presence of alkaline solutions (NaOH, Na2CO3, KOH and K2CO3). Oil products were extracted from both liquid and solid portion by different solvents and analyzed individually. The effect of base solutions on the yield of oil products and composition of oils obtained at different stages were discussed in detail. Based on the conversion and yield of liquid products, the catalytic activity can be ranked as follows: K2CO3 &GT; KOH &GT; Na2CO3 &GT; NaOH. In thermal run, the yield of solid residue was about 42% whereas it was 4.0% in the presence of K2CO3. Catalytic hydrothermal treatment of biomass produced mainly phenolic compounds. In thermal run, furan derivatives were observed whereas these compounds could not be observed in catalytic runs. The volatility distribution of hydrocarbons (ether extract) was characterized by using C-NP gram and it showed that the majority of hydrocarbons for all runs including thermal were distributed boiling point range of n-C-11. The products from hydrothermal treatment of wood biomass were analyzed using GC-MS, H-1 NMR, C-13 NMR, TOC and ion chromatograph. &COPY; 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cej.2005.01.007

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Low-temperature catalytic hydrothermal treatment of wood biomass: analysis of liquid products

S Karagoz, T Bhaskar, A Muto, Y Sakata, T Oshiki, T Kishimoto

CHEMICAL ENGINEERING JOURNAL 108 ( 1-2 ) 127 - 137 2005.4

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE SA

DOI： 10.1016/j.cej.2005.01.007

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Preparation, structural characterization, and reactions of tantalum-alkyne complexes TaCl3((RC)-C-1 CR2)L-2 (L-2 = DME, bipy, and TMEDA; L = Py)

T Oshiki, K Tanaka, J Yamada, T Ishiyama, Y Kataoka, K Mashima, K Tani, K Takai

ORGANOMETALLICS 22 ( 3 ) 464 - 472 2003.2

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

Tantalum-alkyne complexes with the general formula TaCl3(R(1)CdropCR(2))(dme) (1a, R-1 = R-2 = Et; 1b, R-1 = R-2 = n-C5H11; 1c, R-1 = Ph, R-2 = Me; 1d, R-1 = R-2 = Ph; DME = 1,2-dimethoxyethane) were synthesized by treatment of the corresponding alkynes with a low-valent tantalum derived by reduction of tantalum pentachloride with zinc powder in a mixed solvent of toluene and DME. The DME ligand can be replaced by 2 equiv of pyridine to afford the corresponding dipyridine complexes TaCl3(R(1)CdropCR(2))(py)(2) (2a, R-1 = R-2 = Et; 2b, R-1 = R-2 = n-C5H11; 2c, R-1 = Ph, R-2 = Me; 2d, R-1 = R-2 = Ph). Additionally, the reaction of 1a with the bidentate nitrogen ligands bipyridine and N,N,N',N'-tetramethyethylenediamine (= TMEDA) gave TaCl3(EtCdropCEt)(bipy) (3) and TaCl3(EtCdropCEt)(tmeda) (4), respectively. The eta(2)- and 4e-coordination mode of an alkyne with a large contribution of a metalacyclopropene canonical structure was revealed by spectroscopic methods (NMR and IR) and crystallographic analyses of 1a, 1c, 2a, and 4. The reactivies of the tantalum-3-hexyne complexes la, 2a, 3, and 4 toward 3-phenylpropanal were investigated. Only the pyridine complex 2a reacted with a stoichiometric amount of the aldehyde to afford the corresponding allylic alcohol in 77% yield upon hydrolysis. The reaction proceeded via an oxatantalacyclopentene species.

DOI： 10.1021/om020510x

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錯体触媒によるC－H結合活性化を利用した置換ベンゼン類の新合成法

Organometallics News ( 3 ) 103 2001

新しい均一系クロム錯体触媒によるオレフィン重合

触媒 43 ( 3 ) 235 2001

Determination of the absolute configuration of partly fluorinated allylic alcohols; the first synthesis of optically pure 1,2-difluoroallylic alcohols

Yumiko Takagi, Takiko Nakatani, Toshiyuki Itoh, Toshiyuki Oshiki

Tetrahedron Letters 41 ( 41 ) 7889 - 7892 2000.10

Language：English Publishing type：Research paper (scientific journal)

Optically active 1,1,2-trifluoro- or 1,2-difluoroallylic alcohols were prepared via a lipase-catalyzed reaction and their absolute configuration was determined by an X-ray crystallographic analysis of the corresponding ferrocene ester along with the refined Mosher method (the Kusumi-Ohtani method). © 2000 Elsevier Science Ltd.

DOI： 10.1016/S0040-4039(00)01349-6

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SYNTHESIS AND REACTIONS OF OPTICALLY-ACTIVE PHOSPHINE-BORANES

T IMAMOTO, T OSHIKI, T ONOZAWA, M MATSUO, T HIKOSAKA, M YANAGAWA

HETEROATOM CHEMISTRY 3 ( 5-6 ) 563 - 575 1992.10

Language：English Publishing type：Research paper (scientific journal) Publisher：JOHN WILEY & SONS INC

Synthesis and reactions of optically active phosphine-boranes have been investigated. Optically active secondary phosphine-boranes, (S(p))-and (R(p))-menthyloxyphenylphosphine-boranes, and (S)-methylphenylphosphine-borane underwent palladium(0)-catalyzed electrophilic arylation with o-, m-, or p-iodoanisole. The stereochemistry of this arylation was largely dependent on the solvent and the base used. The reaction in acetonitrile proceeded with almost complete retention of configuration at the chiral phosphorus, whereas inversion of configuration was observed in ethereal solvents or toluene. The phosphorus-oxygen bond of (R(p))-menthyloxy (methyl)phenylphosphine-borane and (S(p))-menthy-loxy(o-methoxyphenyl)phenylphosphine-borane was reductively cleaved at -78-degrees-C by lithium naphthalenide or Li/NH3 with virtually net retention of configuration at phosphorus, providing secondary or tertiary phosphine-boranes in excellent yields. New synthetic routes to optically pure C2-symmetric bisphosphine-boranes possessing chirality at phosphorus have been developed on the basis of these stereochemical studies.

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SYNTHESIS AND REACTIONS OF PHOSPHINE BORANES - SYNTHESIS OF NEW BIDENTATE LIGANDS WITH HOMOCHIRAL PHOSPHINE CENTERS VIA OPTICALLY PURE PHOSPHINE BORANES

T IMAMOTO, T OSHIKI, T ONOZAWA, T KUSUMOTO, K SATO

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 112 ( 13 ) 5244 - 5252 1990.6

The Reactions of Optically Pure Menthyloxymethylphenylphosphine-Borane with Organolithium Reagents(共著)

Toshiyuki Oshiki, Tsuneo Imamoto

Bulletin of the Chemical Society of Japan 63 ( 12 ) 3719 - 3721 1990

Synthesis of Organic Phosphorus Compounds Containing a Linear P-B Bond Chain(共著)

Tetrahedron Letters 30 ( 3 ) 383 - 384 1989

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