研究者詳細 - 西原　康師

論文 - 西原　康師

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A NOVEL THREE-COMPONENT COUPLING REACTION OF ARYNES, ISOCYANIDES, AND CYANOFORMATES: A STRAIGHTFORWARD ACCESS TO CYANO-SUBSTITUTED IMINOISOBENZOFURANS 査読

Jing Li, Shintaro Noyori, Masayuki Iwasaki, Kiyohiko Nakajima, Yasushi Nishihara

HETEROCYCLES 86 ( 2 ) 933 - 940 2012年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

Iminoisobenzofuran derivatives have been prepared in moderate yields by the palladium-catalyzed three-component coupling reaction of arynes, isocyanides, and cyanoformates. This paper is dedicated to Professor Ei-ichi Negishi on the occasion of his 77th birthday.

DOI： 10.3987/COM-12-S(N)77

Synthesis of Unsymmetrical Diarylethynes by Pd(0)/Cu(I)-cocatalyzed Sila-Sonogashira-Hagihara Coupling Reactions of Alkynylsilanes with Aryl Tosylates or Mesylates 査読

Yasushi Nishihara, Daisuke Ogawa, Shintaro Noyori, Masayuki Iwasaki

CHEMISTRY LETTERS 41 ( 11 ) 1503 - 1505 2012年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：CHEMICAL SOC JAPAN

Palladium/copper-cocatalyzed cross-coupling reactions of alkynylsilanes with aryl tosylates or mesylates afforded the corresponding unsymmetrical diarylethynes in moderate to good yields. The optimized reaction conditions to afford higher yields of cross-coupled products were found to be 5 mol % of [PdCl2(bpy)], 15 mol % of BrettPhos, and 10 mol % of (CuCl)-Cl-I in DMF as a solvent.

DOI： 10.1246/cl.2012.1503

Synthesis of unsymmetrically disubstituted ethynes by the palladium/copper(I)-cocatalyzed sila-Sonogashira-Hagihara coupling reactions of alkynylsilanes with aryl iodides, bromides, and chlorides through a direct activation of a carbon-silicon bond 査読

Yasushi Nishihara, Eiji Inoue, Shintaro Noyori, Daisuke Ogawa, Yoshiaki Okada, Masayuki Iwasaki, Kentaro Takagi

TETRAHEDRON 68 ( 24 ) 4869 - 4881 2012年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

In this paper, we explore the copper/palladium-cocatalyzed cross-coupling reactions of 1-aryl-2-trimethylsilylethynes with aryl iodides, bromides, and chlorides as coupling partners, to furnish unsymmetrically disubstituted ethynes in moderate to excellent yields. Various aryl iodides were subjected to reaction under the optimized conditions with 5 mol % of Pd(PPh3)(2) and 50 mol % of CuCl. The steric properties of the aryl iodide proved more influential to the outcome of the cross-coupling reaction than electronic factors. In addition, we succeeded in synthesizing unsymmetrical diarylethynes using two different aryl iodides in one-pot. Furthermore, under the same reaction conditions with 10 mol % of PdCl2, 40 mol % of P(4-FC6H4)(3), and 50 mol % of CuCl as catalyst, we succeeded in synthesizing unsymmetrical diarylethynes from various aryl bromides. Finally, we explored reactions with aryl chlorides and duly discovered that unsymmetrical diarylethynes were obtainable in moderate to good yields when 10 mol % of Pd(OAc)(2), 10 mol % of (-)-DIOP, and 10 mol % of CuCl were used. These reactions proceed through a direct activation of a carbon silicon bond in alkynylsilanes by CuCl to generate the corresponding alkynylcopper species via transmetalation from silicon to copper. Mechanistic investigations on the reaction of alkynylsilanes with aryl bromides confirmed that the trimethylsilyl bromide generated in situ retarded both transmetalation steps between CuCl and alkynylsilane, and between palladium(II) species formed by oxidative addition and alkynylcopper species. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2012.03.093

Iron-Catalyzed Oxidation of Tertiary Amines: Synthesis of beta-1,3-Dicarbonyl Aldehydes by Three-Component C-C Couplings 査読

Weiping Liu, Jinhua Liu, Daisuke Ogawa, Yasushi Nishihara, Xingwei Guo, Zhiping Li

ORGANIC LETTERS 13 ( 23 ) 6272 - 6275 2011年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

beta-1,3-Dicarbonyl aldehydes were synthesized by iron-catalyzed oxidative reactions between 1,3-dicarbonyl compounds and two molecules of tertiary amines in the presence of tert-butyl hydroperoxide (TBHP). alpha,beta-Unsaturated aldehydes generated by tertiary amine oxidation In situ act as key intermediates under mild reaction conditions.

DOI： 10.1021/ol202749x

Copper-catalyzed Sila-Sonogashira-Hagihara Cross-coupling Reactions of Alkynylsilanes with Aryl Iodides under Palladium-free Conditions

Yasushi Nishihara, Shintaro Noyori, Takeru Okamoto, Masato Suetsugu, Masayuki Iwasaki

CHEMISTRY LETTERS 40 ( 9 ) 972 - 974 2011年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：CHEMICAL SOC JAPAN

An efficient and inexpensive catalytic system using a readily available CuCl/PPh3 combination for the catalytic cross-coupling reactions of alkynylsilanes with a variety of aryl iodides affords unsymmetrical diarylethynes in good to excellent yields.

DOI： 10.1246/cl.2011.972

Rh-Catalyzed Carbonylation of Arylzinc Compounds Yielding Symmetrical Diaryl Ketones by the Assistance of Oxidizing Agents

Kana Kobayashi, Yugo Nishimura, Fuxing Gao, Kazuma Gotoh, Yasushi Nishihara, Kentaro Takagi

JOURNAL OF ORGANIC CHEMISTRY 76 ( 6 ) 1949 - 1952 2011年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Carbonylative homocoupling of arylzinc compounds 1 using 1 atm of CO and 1,2-dibromoethane as an oxidant was achieved in the presence of Rh-dppf catalyst, affording symmetrical diaryl ketones in good yields. Under similar conditions, Pd or Ni catalysts induced oxidative homo coupling of 1 to yield biaryls instead. The beneficial catalysis by Rh in the carbonylation was presumed to stem from the facility by which the migration of the aryl ligand to CO at the Rh3+ intermediate occurred.

DOI： 10.1021/jo1025173

Improvement in sulfur desorption of NOX storage and reduction catalysts using a Ba-Ti composite oxide

Toshiyuki Tanaka, Ichirou Tajima, Yuichi Kato, Yasushi Nishihara, Hirofumi Shinjoh

APPLIED CATALYSIS B-ENVIRONMENTAL 102 ( 3-4 ) 620 - 626 2011年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

A Ba-Ti composite oxide was formed on a NOx storage and reduction catalyst via impregnation of a Ba-Ti precursor solution composed of H2O2 added to a complex prepared using the citric acid method. The structure of the Ba-Ti composite in solution was analyzed by chemical composition analysis and FT-Raman and UV-vis spectroscopy. MM2 calculations were performed to propose its chemical structure. Both Ba and Ti together were found to form a composite molecule in the solution. Furthermore, TEM-EDX and XRD analyses of the Ba-Ti composite oxide on the catalyst prepared by impregnation with the Ba-Ti composite aqueous solution revealed that Ba and Ti in the catalyst were highly dispersed at the nm scale. The formation of the Ba-Ti composite oxide on the NSR catalyst enhanced sulfur desorption efficiency and led to high-performance NOX conversion as a NOX storage and reduction activity catalyst after desulfation treatment. It was assumed that the existence of nano-scaled Ba compounds combined with Ti was efficient for the inhibition of the sintering of barium sulfate and its facile decomposition. It was found that dispersion of Ba compounds for NOX storage materials using a Ba-Ti complex solution is an efficient way to improve the durability of NSR catalysts. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcatb.2011.01.002

Highly Regio- and Stereoselective Synthesis of Multialkylated Olefins through Carbozirconation of Alkynylboronates and Sequential Negishi and Suzuki-Miyaura Coupling Reactions

Yasushi Nishihara, Yoshiaki Okada, Jiao Jiao, Masato Suetsugu, Ming-Tzu Lan, Megumi Kinoshita, Masayuki Iwasaki, Kentaro Takagi

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 50 ( 37 ) 8660 - 8664 2011年

Negishi Alkyl-Aryl Cross-Coupling Catalyzed by Rh: Efficiency of Novel Tripodal 3-Diphenylphosphino-2-(diphenylphosphino)methyl-2-methylpropyl Acetate Ligand

Syogo Ejiri, Shunsuke Odo, Hideki Takahashi, Yugo Nishimura, Kazuma Gotoh, Yasushi Nishihara, Kentaro Takagi

ORGANIC LETTERS 12 ( 8 ) 1692 - 1695 2010年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

3-Diphenylphosphino-2-(diphenylphoshino)methyl-2-methylpropyl acetate acted as an efficient ligand for a Rh catalyst, achieving cross-coupling between arylzinc compounds bearing electron-withdrawing groups and alkyl electrophiles. The beneficial effect of the tripodal ligand and such aryl nucleophiles was discussed with regard to the specificity of the Rh catalysis.

DOI： 10.1021/ol100210u

Enantioseparation of Doubly Functionalized Polar Norbornenes by HPLC and Their Ruthenium-Catalyzed Ring-Opening Metathesis Polymerization

Yasushi Nishihara, Yukiko Doi, Seisuke Izawa, Horng-Yi Li, Yoshiaki Inoue, Masaaki Kojima, Jwu-Ting Chen, Kentaro Takagi

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 48 ( 2 ) 485 - 491 2010年1月

Palladium- and base-free synthesis of conjugated ynones by cross-coupling reactions of alkynylboronates with acid chlorides mediated by CuCl

Yasushi Nishihara, Daisuke Saito, Eiji Inoue, Yoshiaki Okada, Mikihiro Miyazaki, Yoshiaki Inoue, Kentaro Takagi

TETRAHEDRON LETTERS 51 ( 2 ) 306 - 308 2010年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

Alkynylboronates can be employed as a practical and versatile precursor for a variety of pi-conjugated organic compounds. In the presence of Cu(I) salt, cross-coupling reactions of acid chlorides with alkynylboronates giving rise to the corresponding conjugated ynones takes place readily in aprotic polar solvents such as DMI under neutral conditions. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2009.11.001

Development of New Methodology for Bond Activation by Transition Metal Complexes and Their Application toward Functional Molecule Synthesis

Yasushi Nishihara

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN 67 ( 9 ) 889 - 897 2009年9月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：SOC SYNTHETIC ORGANIC CHEM JPN

In this review, the results of studies on new methodology for bond activation by using transition metal complexes are described, in order to realize the expeditious and selective synthesis of organic compounds. Carbon-carbon bond formation reactions, accompanying with cleavage of unactivated bonds such as carbon-carbon, carbon-boron, and carbon-silicon bonds, are reported. This review involves, for examples, the new synthetic methodology to introduce both cyano and ester groups (cyanoesterification) via the C-C bond activation, regio- and stereoselective synthesis multi-substituted olefins mediated a zirconocene complex via the C-B bond activation, and cross-coupling reaction of alkynylsilanes activated by a copper salt via the C-Si bond cleavage. Each reaction can be applicable to synthesis of functional molecules such as opto-electronic materials, an anti-cancer agent, and liquid crystalline compounds.

DOI： 10.5059/yukigoseikyokaishi.67.889

Regio- and Stereoselective Synthesis of Multisubstituted Vinylsilanes via Zirconacycles

Yasushi Nishihara, Daisuke Saito, Kenki Tanemura, Shintaro Noyori, Kentaro Takagi

ORGANIC LETTERS 11 ( 16 ) 3546 - 3549 2009年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

A series of novel multisubstituted vinylsilanes are prepared regio- and stereoselectively by carbozirconation of various alkynylsilanes through zirconacycles such as zirconacyclopropenes and zirconacyclopentenes and the subsequent transformation of the formed alkenylzirconocene complexes.

DOI： 10.1021/ol901236s

Palladium/copper-catalyzed sila-Sonogashira reactions of aryl iodides with alkynylsilanes via a direct C-Si bond activation

Yasushi Nishihara, Eiji Inoue, Daisuke Ogawa, Yoshiaki Okada, Shintaro Noyori, Kentaro Takagi

TETRAHEDRON LETTERS 50 ( 32 ) 4643 - 4646 2009年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

The palladium-catalyzed cross-coupling reactions of aryl iodides with alkynylsilanes in the presence of a substoichiometric amount (50 mol %) of copper(I) chloride as an activator in DMF under strictly non-basic reaction conditions afford the corresponding unsymmetrical diarylethynes in moderate to excellent yields. A wide range of substrates bearing an electron-donating or an electron-withdrawing substituent on the aromatic ring are compatible. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2009.05.112

Comparative reactivity of triorganosilanes, HSi(OEt)(3) and HSiEt3, with IrCl(CO)(PPh3)(2). Formation of IrCl(H)(2)(CO)(PPh3)(2) or Ir(H)(2)(SiEt3)(CO)(PPh3)(2) depending on the substituents at Si

Yasushi Nishihara, Miwa Takemura, Kohtaro Osakada

INORGANICA CHIMICA ACTA 362 ( 8 ) 2951 - 2956 2009年6月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE SA

Reaction of HSi(OEt)(3) with IrCl(CO)(PPh3)(2) (5:1 molar ratio) at room temperature for 1 h gives IrCl(H){Si(OEt)(3)}(CO)(PPh3)(2) (1), which is observed by the H-1 and P-31{H-1} NMR spectra of the reaction mixture. The same reaction, but in 20:1 molar ratio at 50 degrees C for 24 h produces IrCl(H)(2)(CO)(PPh3)(2) (2) rather than the expected product Ir(H)(2){Si(OEt)(3)}(CO)(PPh3)(2) (3) that was previously reported to be formed by this reaction. Accompanying formation of Si(OEt)(4), (EtO)(3)SiOSi(OEt)(3), and (EtO)(2)HSiOSi(OEt)(3) is observed. On the other hand, trialkylhydrosilane HSiEt3 reacts with IrCl(CO)(PPh3)(2) (10:1 molar ratio) at 80 degrees C for 84 h to give Ir(H)(2)(SiEt3)(CO)(PPh3)(2) (4) in a high yield, accompanying with a release of ClSiEt3. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ica.2008.12.033

Rh-Catalyzed Negishi Alkyl-Aryl Cross-Coupling Leading to alpha- or beta-Phosphoryl-Substituted Alkylarenes

Hideki Takahashi, Shinya Inagaki, Naoko Yoshii, Fuxing Gao, Yasushi Nishihara, Kentaro Takagi

JOURNAL OF ORGANIC CHEMISTRY 74 ( 7 ) 2794 - 2797 2009年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

The catalytic cross-coupling between ArZnX and ICH(2)(CH(2))(n)P(O)(OEt)(2) (n = 0-3) has been investigated to determine the utility of the Rh catalyst during the alkyl-aryl cross-coupling and to develop a new synthetic method for phosphoryl-substituted alkylarenes. Rh-dppf exhibits an excellent catalytic activity for the reaction with the alkylphosphonate of n = 1, whereas for the reaction with those of n = 2 or 3, P-hydride elimination mainly takes place. As for the reaction with an alkylphosphonate of n = 0, a polarity inversion of the coupling components is necessary in order to provide the coupling products; the phosphoryl analogue of the Reformatsky reagent and ArI give the cross-coupling products in good yields through the catalysis by Rh-dppf.

DOI： 10.1021/jo900142b

Photocatalytic Activities of Graphitic Carbon Nitride Powder for Water Reduction and Oxidation under Visible Light

Kazuhiko Maeda, Xinchen Wang, Yasushi Nishihara, Daling Lu, Markus Antonietti, Kazunari Domen

JOURNAL OF PHYSICAL CHEMISTRY C 113 ( 12 ) 4940 - 4947 2009年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Graphitic carbon nitride (g-C(3)N(4)) with a band gap of 2.7 eV is studied as a nonmetallic photocatalyst for H(2) or O(2) evolution from water under ultraviolet (UV) and visible light. The g-C(3)N(4) catalyst exhibits activities for water reduction into H(2) or water oxidation into O(2) in the presence of a proper sacrificial electron donor or acceptor, respectively, even without the need for precious metal cocatalysts. When bis(1,5-cyclooctadiene)platinum complex [Pt(cod)(2)] (a nonionic complex) is used as a precursor of Pt cocatalyst instead of H(2)PtCl(6) (an ionic complex), enhanced H(2)) evolution activity is acquired. This difference in activity is primarily due to the better dispersion of Pt nanoparticles on g-C(3)N(4), which is considered to originate from the better access of Pt(cod)(2) to the g-C(3)N(4) surface, as compared to that of H(2)PtCl(6) in the preparation process. Unmodified g-C(3)N(4) produces O(2) from an aqueous silver nitrate solution upon UV irradiation (lambda > 300 nm), although N(2), release due to self-decomposition of g-C(3)N(4) by photogenerated holes takes place. Modification of g-C(3)N(4) with RuO(2), improves not only O(2) evolution activity but also stability against the self-decomposition, resulting in stable visible-light-driven O(2) evolution (lambda > 420 nm).

DOI： 10.1021/jp809119m

Sila-Sonogashira Cross-Coupling Reactions of Activated Aryl Chlorides with Alkynylsilanes

Yasushi Nishihara, Eiji Inoue, Yoshiaki Okada, Kentaro Takagi

SYNLETT ( 19 ) 3041 - 3045 2008年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：GEORG THIEME VERLAG KG

The palladium/copper-cocatalyzed sila-Sonogashira cross-coupling reactions of activated aryl chlorides with alkynylsilanes under strictly nonbasic conditions yield the unsymmetrical diarylethynes in moderate to good yields.

DOI： 10.1055/s-0028-1087345

Synthesis and Ion Conductive Characteristics of Inorganic-Organic Hybrid Polymers Bearing a Tetraarylpentaborate Unit

Yasushi Nishihara, Mikihiro Miyazaki, Yasumasa Tomita, Yuuki Kadono, Kentaro Takagi

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 46 ( 23 ) 7913 - 7918 2008年12月

Synthesis, characterization, and thermal properties of ring-opening metathesis polynorbornenes and their hydrogenated derivatives bearing various ester and cyano groups

Yasushi Nishihara, Seisuke Izawa, Yoshiaki Inoue, Yuushou Nakayama, Takeshi Shiono, Kentaro Takagi

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY 46 ( 10 ) 3314 - 3325 2008年5月

記述言語：英語出版者・発行元：JOHN WILEY & SONS INC

Doubly functionalized polar norbornenes 3a-3g substituted by both a variety of ester and cyano groups were polymerized by ring-opening metathesis polymerization (ROMP) with a Ru carbene complex 2 bearing 3-bromopyridine as a ligand (third generation Grubbs' catalyst) in a living manner. The successive hydrogenation of the main-chain double bond in the synthesized living ROMP polymers 4a-4g with a hydridoruthenium complex was exploited. The comparison of thermal properties of a series of ring-opening metathesis polymers 4a-4g with those of their hydrogenated derivatives 5a-5g revealed the decrease of glass transition temperatures (T-g) but little change of the 5% decomposition temperature (T-d(5)). In all cases examined in this study, a decrease of T-g by hydrogenation was around 20-40 degrees C, regardless of the ester substitutents. In the presence of the additional PCy3, triethylamine, and methanol after complete consumption of monomer 3a under the living ROMP condition, the tandem ROMP-hydrogenation of the resulting polymer 4a generated in situ was attained under a H-2 (9.8 MPa) atmosphere at 80 degrees C to afford the hydrogenated polymer 5a, retaining the narrow polydispersity of 1.03. (C) 2008 Wiley Periodicals, Inc.

DOI： 10.1002/pola.22671

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