Faculty Profiles - OSHIKI Toshiyuki

Papers - OSHIKI Toshiyuki

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Control of the electronic and optical properties of aminoxyl radicals via boron complexation. Reviewed International journal

Takuma Kuroda, Peiyuan Yang, Marika Nakamura, Risa Hyakutake, Hiroki Fukumoto, Toshiyuki Oshiki, Yuta Nishina, Koichiro Masada, Takahiro Sasamori, Yosihiyuki Mizuhata, Kazuya Kubo, Ryo Inoue, Tomohiro Agou

Dalton transactions (Cambridge, England : 2003) 2024.11

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

Stable radicals have attracted increasing attention in recent years because of their unique electronic and optical characteristics. Aminoxyl radicals are one of the most widely studied stable radicals to date, but their applications in opto-functional materials have yet to be explored in detail. Our group previously reported the boron complexes of aminoxyl radicals exhibit near-infrared (NIR) absorption. In this work, an aminoxyl radical without boron-complexation was synthesized to elucidate the effects of boron coordination on the properties of the aminoxyl radicals. The results of electron spin resonance spectroscopy, ultraviolet-visible-NIR absorption measurements, and density functional theory calculations indicated that boron complexation facilitated spin delocalization over the radical π-frameworks. Furthermore, a π-extended aminoxyl radical-boron complex exhibited a significant wavelength-shift to longer wavelengths in the NIR-II absorption region, thereby reflecting its larger π-conjugated radical skeleton.

DOI： 10.1039/d4dt02973a

Origin of the Two Major Types of Repeating Units in Poly(β-pinene) Obtained by Cationic Polymerization Reviewed

Oluwaseyi Aderemi Ajala, Shogo Nakaichi, Toshiyuki Oshiki, Yuushou Nakayama, Takeshi Shiono, Ryo Tanaka

Macromolecules 57 ( 19 ) 9257 - 9264 2024.9

Synthesis and Optical Properties of Dithieno-1,4-Thiaborins Bearing Electron-Donating Amino Groups Reviewed

Tomohiro Agou, Shota Hayama, Naoya Takano, Shigeyuki Yamada, Tsutomu Konno, Toshiyuki Oshiki, Hidehito Komatsuzaki, Hiroki Fukumoto

Bulletin of the Chemical Society of Japan 2024.2

Publishing type：Research paper (scientific journal) Publisher：Oxford University Press (OUP)

Abstract

Dibenzo-1,4-heteraborins and their π-extended derivatives have been paid increased attention to because of their potential as optical and electronic functional materials such as organic electroluminescence emitters. Meanwhile, 1,4-heteraborin compounds with heteroaromatic ring systems have remained scarce, even though Liu et al. recently reported the synthesis, properties and functionalization of dithieno-1,4-thiaborins (DTTBs). In this work, DTTBs with 10H-phenothiazine-10-yl (Pz), 9H-carbazol-9-yl (Cz), and p-(Ph2N)C6H4 groups as electron-donating amino groups at the α-positions of the thiophene moieties were synthesized using palladium-catalyzed coupling reactions. X-Ray crystallographic analysis revealed the molecular structure of a DTTB substituted with Pz groups. This analysis showed that the two Pz moieties adopted extra- (quasi-axial) conformations. The Cz and p-(Ph2N)C6H4 substituted DTTBs showed red-shifted absorption and emission when compared to the original DTTBs. This shift is due to donor–acceptor interactions between the amino groups and the DTTB cores. The Pz-substituted DTTB exhibited dual fluorescence emissions, originating from the locally-excited (LE) and twisted intramolecular charge transfer (TICT) states. The intensity and nature of these emissions varied based on solvent polarity, temperature, and viscosity, suggesting the potential of the Pz-substituted DTTB to act as a fluorescent environment sensor.

DOI： 10.1093/bulcsj/uoae014

A Practical Method for the Measurement of 183W NMR Signals in Solution: Challenge to Multinuclear Solution NMR Invited

Toshiyuki Oshiki

58 ( 1 ) 2023.7

A Practical Method for the Measurement of 183W NMR Signals in Solution: Challenge to Multinuclear Solution NMR Invited

55 ( 1 ) 16 - 23 2023.6

Synthesis and characterization of a polystyrene-type polymer bearing a cyclic perfluoroalkylene group Reviewed

Tatsuro Hisa, Yasunori Kanno, Tomohiro Shirai, Toshiyuki Oshiki, Yoshiyuki Mizuhata, Norihiro Tokitoh, Hiroki Fukumoto, Tomohiro Agou

Polymer 265 125588 - 125588 2022.12

Synthesis of perfluoroalkylene-vinylene-arylene copolymers via the Mizoroki-Heck co-polymerization of 1,4-divinylperfluorobutane and 1,6-divinylperfluorohexane with dihalogenated arylene monomers Reviewed

Hiroto Tsukada, Tatsuro Hisa, Tomohiro Shirai, Toshiyuki Oshiki, Yoshiyuki Mizuhata, Norihiro Tokitoh, Hiroki Fukumoto, Tomohiro Agou

Journal of Fluorine Chemistry 261-262 110033 - 110033 2022.9

Presence of Microplastics in Four Types of Shellfish Purchased at Fish Markets in Okayama City, Japan. Reviewed

Kenichi Yamamoto, Toshiyuki Oshiki, Hiroko Kagawa, Masayoshi Namba, Masakiyo Sakaguchi

Acta medica Okayama 75 ( 3 ) 381 - 384 2021.6

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

The worldwide microplastic pollution in our environment is a matter of great concern. Harmful effects of plastics have been reported in various types of organisms including murine animals. We examined the presence of microplastics in four types of shellfish purchased from fish markets in Okayama, Japan and served to the public: short-neck clam (Ruditapes philippinarum, asari in Japanese), hard-shell clam (Meretrix lusoria, hamaguri), brackishwater clam (Cyrenidae, shijimi), and oyster (Crassostrea gigas, kaki). Our analyses demonstrated that approx. 3 pieces of microplastics were present per single shellfish, based on the division of the total number of pieces of microplastic obtained from all 4 types of shellfish by the total number of shellfish examined. Since health problems in humans due to microplastics have not yet been confirmed, further examinations of the effects of ingested microplastics are needed.

DOI： 10.18926/AMO/62234

Alcohol Extracts from Plastic Wrap induces Cytotoxic Effect on Culture cells

山本健一, TAN Xian Wen, 有元佐賀恵, 押木俊之, 難波正義, 阪口政清

組織培養研究(Web) 39 ( 1 ) 2021

Cytotoxic Effects of Alcohol Extracts from a Plastic Wrap (Polyvinylidene Chloride) on Human Cultured Liver Cells and Mouse Primary Cultured Liver Cells. Reviewed

Ken-Ichi Yamamoto, Hiroko Kagawa, Sakae Arimoto, Xian Wen Tan, Kento Yasui, Toshiyuki Oshiki, Masakiyo Sakaguchi

Acta medica Okayama 74 ( 4 ) 327 - 334 2020.8

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

An increasing accumulation of microplastics and further degraded nanoplastics in our environment is suspected to have harmful effects on humans and animals. To clarify this problem, we tested the cytotoxicity of two types of plastic wrap on human cultured liver cells and mouse primary cultured liver cells. Alcohol extracts from plastic wrap, i.e., polyvinylidene chloride (PVDC), showed cytotoxic effects on the cells. Alcohol extracts of polyethylene (PE) wrap were not toxic. The commercially available PVDC wrap consists of vinylidene chloride, epoxidized soybean oil, epoxidized linseed oil as a stiffener and stabilizer; we sought to identify which component(s) are toxic. The epoxidized soybean oil and epoxidized linseed oil exerted strong cytotoxicity, but the plastic raw material itself, vinylidene chloride, did not. Our findings indicate that plastic wraps should be used with caution in order to prevent health risks.

DOI： 10.18926/AMO/60371

微生物が生み出す安全で鮮やかな赤色顔料と固体触媒

中西真, 押木俊之, 田村勝徳, 高田潤

塗装工学 54 ( 2 ) 2019

Structural Characterization and Unique Catalytic Performance of Silyl-Group-Substituted Geminal Dichromiomethane Complexes Stabilized with a Diamine Ligand Reviewed

Masahito Murai, Ryuji Taniguchi, Naoki Hosokawa, Yusuke Nishida, Hiroko Mimachi, Toshiyuki Oshiki, Kazuhiko Takai

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 139 ( 37 ) 13184 - 13192 2017.9

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

Stabilization by a silyl group on the methylene carbon and a diamine ligand led to the isolation of gem-dichromiomethane species. X-ray crystallography confirmed the identity of the structure of this rare example of reactive gem-dimetalloalkane species. The isolated gem-dichromiomethane complex acted as a storable silylmethylidene carbene equivalent, with reactivity that could be changed dramatically upon addition of a Lewis acid (ZnCl2) and a base (TMEDA) to promote both silylalkylidenation of polar aldehydes and silylcyclopropanation of nonpolar alkenes. Identification of a key reactive species also identified the catalytic version of these transformations and provided insights into the reaction mechanism. In contrast to Simmons-Smith cyclopropanation, the real reactive species for the current cyclopropanation was a chromiocarbene species, not a chromium carbenoid species.

DOI： 10.1021/jacs.7b07487

Industrial Application and Olefin Metathesis Catalyst Technologies for Reaction Injection Molding of Dicyclopentadiene Reviewed

Michiru Kamada, Toshiyuki Oshiki

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN 75 ( 2 ) 19 - 28 2017.2

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SOC SYNTHETIC ORGANIC CHEM JPN

Current technologies of DCP-RIM (reaction injection molding of dicyclopentadiene) are reviewed from an industrial point of view. The DCP-RIM provides high-impact, heat resistant, and insulating poly (dicyclopentadiene) thermoset resin via catalytic olefin metathesis. Control of chemical reactivities of the catalysts is one of the most important technologies for the DCP-RIM. The key properties of the catalysts are their good solubility in dicyclopentadiene and latency.
Suitable tungsten or molybdenum-based catalyst systems have been developed and used for over 30 years. These catalyst systems are comprised of inorganic tungsten (or molybdenum) salt and an air-sensitive organoaluminum as an activator. In contrast, robust Grubbs type ruthenium-alkylidene catalysts are attracted great interest in the field of the DCP-RIM. Detailed structure and reactivities of the ruthenium catalysts for the DCP-RIM are summarized.

DOI： 10.5059/yukigoseikyokaishi.75.111

New Catalyst Technology for Industrial Production of Polydicyclopentadiene Molding

押木俊之, 鎌田満, 鎌田満, 西岡直樹

山陽技術雑誌 61 10 - 14 2014.4

革新的プロセス開発の新展開産業界と連携した革新性ある錯体触媒プロセスの開発

押木俊之

ケミカルエンジニヤリング 59 ( 2 ) 93 - 100 2014.2

PH effect on properties of surfactant-free oil-in-water emulsion prepared with oleic acid Reviewed

Yuta Akizuki, Mikio Yoshida, Naoyuki Ishida, Toshiyuki Oshiki, Jun Oshitani

Chemistry Letters 43 ( 5 ) 604 - 606 2014

Language：English Publishing type：Research paper (scientific journal) Publisher：Chemical Society of Japan

Size distribution, potential, and yield of surfactant-free oil-in-water (O/W) emulsion prepared with oleic acid were measured at various pHs after seven days from the emulsification. We found that the size distribution is almost the same regardless of pH from 9 to 3. The magnitude of potential and yield remains constant at pH from 9 to 6, and decreases at pH from 6 to 3. There is a correlation between the potential and the yield, but no correlation between the potential and the size, suggesting that the potential relates to stability of oleic acid droplets in water rather than their size. © 2014 The Chemical Society of Japan.

DOI： 10.1246/cl.131209

Preparation of Magnetic Ionic Liquids Composed of Hybrid-Type Anions Reviewed

Yumiko Takagi, Yoriko Kusunoki, Yukihiro Yoshida, Hirofusa Tanaka, Gunzi Saito, Kosuke Katagiri, Toshiyuki Oshiki

AUSTRALIAN JOURNAL OF CHEMISTRY 65 ( 11 ) 1557 - 1560 2012

Language：English Publishing type：Research paper (scientific journal) Publisher：CSIRO PUBLISHING

1-Ethyl-3-methylimidazolium ethylsulfate ([C(2)mim][EtSO4]) was mixed with iron(III) chloride center dot 6H(2)O to give a magnetic ionic liquid composed of the hybrid-type anion, [C(2)mim][FeCl3 center dot EtSO4], which showed a slightly different magnetic property than [C(2)mim][FeCl4]. On the other hand, reaction of [C(2)mim][EtSO4] with cobalt(II) chloride hydrate formed [C(2)mim](2)[(CoCl4)-Cl-II], the structure of which was characterised by X-ray crystallographic analysis.

DOI： 10.1071/CH12331

Iridium complexes for the catalytic hydration of acrylonitrile

Oshiki Toshiyuki, Kawakami Yukiko, Muranaka Makoto

Proceeding of Annual/Fall Meetings of the Japan Petroleum Institute 42nd 133 - 133 2012

2-Diphenylphosphanyl-4-pyridyl(dimethyl) amine as an effective ligand for the ruthenium(II) complex catalyzed homogeneous hydration of nitriles under neutral conditions Reviewed

Makoto Muranaka, Isao Hyodo, Wataru Okumura, Toshiyuki Oshiki

CATALYSIS TODAY 164 ( 1 ) 552 - 555 2011.4

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

New homogeneous catalyst comprised of [Ru(methallyl)(2)(cod)] (cod = 1,5-cyclooctadiene) (1) and 2-diphenylphosphanyl-4-pyridyl(dimethyl) amine (2) is shown to efficiently catalyze the hydration of various nitriles under neutral conditions. The hydration proceeds in the presence of 0.5 mol% of the ruthenium catalyst at 80 degrees C in 1,2-dimethoxyethane solution and the corresponding amide is obtained within few hours without the formation of by products. Comparison of some phosphine ligands for the hydration reveals that the dimethylamino moiety of 2 improves the catalytic performance dramatically. (C) 2010 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.cattod.2010.11.050

問われる日本の研究開発力問われる産と学の決断と勇気

押木俊之

化学経済 58 ( 2 ) 50-55 - 55 2011.2

Highly Reactive Bifunctional Chemical Catalysts for the Hydration of Nitriles

Toshiyuki Oshiki, Isao Hyodo, Akinori Ishizuka

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN 68 ( 1 ) 41 - 51 2010.1

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SOC SYNTHETIC ORGANIC CHEM JPN

New bifunctional chemical catalysts for the hydration of nitriles are described. cis-Ru(acac)(2)(PPh(2)py)(2) exhibited high activity, with a turnover frequency of up to 20,900 (mol of amide)/((mol of catalyst)h). Newly synthesized iridium complexes bearing a PPh(2)py ligand have a 16 e(-) square planar structure. The catalytic hydration of nitriles proceeded at 80 degrees C within few hours to give corresponding amides in almost quantitative yield. Moreover, the iridium complexes acted as a catalyst for the hydration under solvent-free conditions. In addition, new catalysts based on palladium nanoparticles for the hydration are described. Copper compounds containing oxygen atom acted as effective co-catalysts; in the catalytic system.

DOI： 10.5059/yukigoseikyokaishi.68.41

Tebbe錯体円偏光二色性検出２元機能型触媒非局在型一重項ビラジカル

高井和彦, 荒井孝義, 押木俊之, 久保孝史

有機合成化学協会誌 68 ( 1 ) 77 - 77 2010

化学プロセスを見直す加水分解反応の新研究 2元機能型錯体触媒による水和反応

押木俊之

月刊ファインケミカル 38 ( 10 ) 6-14 2009.9

The Hydration of Nitriles Catalyzed by the Combination of Palladium Nanoparticles and Copper Compounds

Akinori Ishizuka, Yoshiaki Nakazaki, Toshiyuki Oshiki

CHEMISTRY LETTERS 38 ( 4 ) 360 - 361 2009.4

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

New catalysts based on Pd nanoparticles for the hydration of nitrites to amides were investigated. Copper compounds containing oxygen acted as effective promoters in the catalytic system. The catalysts could be used to prepare aromatic and aliphatic amides from the corresponding nitrites. Chloride ions significantly inhibited the catalytic performance.

DOI： 10.1246/cl.2009.360

The Hydration of Nitriles Catalyzed by the Combination of Palladium Nanoparticles and Copper Compounds

Ishizuka, A., Nakazaki, Y., Oshiki, T.

Chemistry Letters 38 ( 4 ) 360-361 (J-STAGE) - 361 2009

２元機能型錯体触媒による水和反応

押木俊之

月刊ファインケミカル 38 ( 10 ) 6 - 11 2009

環境対応型の加水分解触媒技術(革新的化学触媒を用いるニトリル類の水和(加水分解)技術)

押木俊之

クリーンテクノロジー 19 51 - 55 2009

Bio-inspired Highly Active Homogeneous Catalysts for Hydration of Nitriles: Activation of Water under Neutral Conditions

T. Oshiki, I. Hyodo, M. Muranaka

J. Biolog. Inorg. Chem. 14(Suppl 1) S230 2009

水の資源・エネルギー問題に着目した新規ニトリル水和プロセス

押木俊之

グリーンケミストリー研究会資料集 45 - 50 2009

Tantalum Complexes Incorporating Tris(pyrazolyl)Borate Ligands: Syntheses, Structures, and Ethylene Polymerization Behavior

Michiue, K., Oshiki, T., Takai, K., Mitani, M., Fujita, T.

Organometallics 28 ( 22 ) 6450 - 6457 2009

Efficient Synthesis of Metal Contained Ionic-liquids

TAKAGI Yumiko, KUSUNOKI Yoriko, OSHIKI Toshiyuki

香川大学教育学部研究報告第2部 58 ( 2 ) 47-52 - 52 2008.10

INOR 832-Synthesis, structures and olefin polymerization behavior of tris(pyrazolyl)borate tantalum complexes Reviewed

Kenji Michiue, Toshiyuki Oshiki, Kazuhiko Takai, Makoto Mitani, Terunori Fujita

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 236 2008.8

高活性錯体触媒法によるアミド製造法の開発

押木俊之, 石塚章斤, 兵頭功

ケミカルエンジニアリング 53 ( 6 ) 440 - 444 2008

Analgesic agents without gastric damage: Design and synthesis of structurally simple benzenesulfonanilide-type cyclooxygenase-1-selective inhibitors (vol 15, pg 1014, 2007) Reviewed

Zheng Xiaoxia, Oda Hiroyuki, Takamatsu Kayo, Sugimoto Yukio, Tai Akihiro, Akaho Eiichi, Ali Hamed Ismail, Oshiki Toshiyuki, Kakuta Hiroki, Sasaki Kenji

BIOORGANIC & MEDICINAL CHEMISTRY 15 ( 9 ) 3299 - 3300 2007.5

Analgesic agents without gastric damage: Design and synthesis of structurally simple benzenesulfonanilide-type cyclooxygenase-1-selective inhibitors Reviewed

Xiaoxia Zheng, Hiroyuki Oda, Kayo Takamatsu, Yukio Sugimoto, Akihiro Tai, Eiichi Akaho, Hamed Ismail Ali, Toshiyuki Oshiki, Hiroki Kakuta, Kenji Sasaki

BIOORGANIC & MEDICINAL CHEMISTRY 15 ( 2 ) 1014 - 1021 2007.1

Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD

In order to create novel analgesic agents without gastric disturbance, structurally simple cyclooxygenase-1 (COX-1) inhibitors with a benzenesulfonanilide skeleton were designed and synthesized. As a result, compounds 11f and 15a, which possess a p-amino group on the benzenesulfonyl moiety and p-chloro group on the anilino moiety, showed COX-1-selective inhibition. Moreover compound 11f, which is the most potent compound in this study showed more potent analgesic activity than that of aspirin at 30 mg/kg by po. The anti-inflammatory activity and gastric damage, however, were very weak or not detectably different from aspirin. Since the structure of our COX-1 inhibitors are very simple, they may be useful as lead compounds for superior COX-1 inhibitors as analgesic agents without gastric disturbance. (c) 2006 Published by Elsevier Ltd.

DOI： 10.1016/j.bmc.2006.10.029

Alkyne exchange reactions of silylalkyne complexes of tantalum: Mechanistic investigation and its application in the preparation of new tantalum complexes having functional alkynes (PhC CR (R = COOMe, CONMe2)) Reviewed

Toshiyuki Oshiki, Atsushi Yamada, Kimio Kawai, Hirotaka Arimitsu, Kazuhiko Takai

ORGANOMETALLICS 26 ( 1 ) 173 - 182 2007.1

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

Silylalkyne complexes of tantalum with the general formula TaCl3((RCCR2)-C-1)L-2 (1, R-1 = R-2 = SiMe3, L-2 = DME; 2, R-1 = SiMe3, R-2 = Me, L-2 = DME; 6, R-1 = R-2 = SiMe3, L = py; 7, R-1 = SiMe3, R-2 = Me, L = py) reacted with an internal alkyne to give corresponding alkyne complexes via an alkyne exchange reaction. These silylalkyne complexes were newly prepared and structurally characterized. Kinetic measurements revealed that the rates of the exchange reactions of the DME complexes 1 and 2 were first-order dependent on the concentration of the complex and the reaction proceeded via dissociative pathway. The exchange reaction rates of the bis(pyridine) complexes 6 and 7 were slower. In contrast to the DME complexes, the exchange reaction of 6 proceeded via an associative interchange pathway, and the exchange mechanism for 7 was an associative pathway. During the exchange, two pyridine ligands coordinated strongly to the tantalum center and the intermediate is proposed to be a bis(alkyne) complex. New tantalum complexes having functional alkynes (PhCCR (R = COOMe, CONMe2)) were prepared from the silylalkyne complexes via the alkyne exchange reaction.

DOI： 10.1021/om060659z

ニトリル類の水和反応を無溶媒で触媒する新規高活性イリジウム錯体の開発

触媒 49 ( 6 ) 412 - 414 2007

Solvent-free hydration of nitriles catalyzed by homogeneous catalysts

Oshiki Toshiyuki, Ishizuka Akinori, Okumura Wataru, Hyodo Isao, Arimitsu Hirotaka, Yokoyama Yutaka, Takai Kazuhiko

Proceeding of Annual/Fall Meetings of the Japan Petroleum Institute 2007 183 - 183 2007

Language：Japanese Publisher：The Japan Petroleum Institute

We will present that newly discovered pyridylphosphine-ruthenium and -iridium complexes are effective for the catalytic hydration of nitriles. Bifunctional ligand-metal catalysis which was observed in the hydration catalyzed with cis-Ru(acac)2(PPh2py)2 could also play an important role in this reaction. A newly synthesized iridium complex, Ir(acac)(PPh2py)2, proved to be an excellent catalyst for the solvent-free hydration of nitriles. The detailed reaction conditions and molecular structures of the catalysts will also be presented.

DOI： 10.11523/sekiyu.2007f.0.183.0

Titanium and zirconium complexes with non-salicylaldimine-type imine-phenoxy chelate ligands: Syntheses, structures, and ethylene-polymerization behavior Reviewed

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

Chemistry-an Asian Journal 1 ( 6 ) 878-887 - 887 2006.12

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

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

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

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

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

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

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

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

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

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.

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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