巻号一覧
63 巻, 2 号
選択された号の論文の8件中1～8を表示しています
- |<
- <
- 1
- >
- >|
-
アセチレン, オレフィン, およびヘテロ不飽和化合物の環化反応占部 弘和2005 年 63 巻 2 号 p. 102-111
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーPreparation of heterocyclic compounds by the assembly of carbon-carbon and carbon-heteroatom unsaturated bonds via group 4 metallacycles was described. The preparative methods are classified into four categories : 1) reaction of metallacycles formed by the coupling of acetylenes and/or olefins with hetero-electrophiles, 2) coupling of two carbon-carbon unsaturated bonds and one carbon-heteroatom unsaturated bond, 3) coupling of one carbon-carbon unsaturated bond and two carbon-heteroatom unsaturated bonds, and 4) intramolecular hetero-metallation of functionalized acetylenes and allenes.抄録全体を表示PDF形式でダウンロード (1274K) -
山本 芳彦2005 年 63 巻 2 号 p. 112-121
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーThe catalytic intramolecular cyclotrimerization of alkynes with various unsaturated molecules were achieved using ruthenium (II) complexes bearing a cyclopentadienyl-type planar ligand as catalyst precursors.
In the presence of a catalytic amount of the Ru (II) complex, a 1, 6-diyne reacted with norbornene to afford a novel tandem cyclopropanation product together with the expected [2+2+2] cycloadduct. On the other hand, the cycloaddition of the diynes with heterocycloalkenes or monoalkynes were catalyzed by pentamethylcyclopentadienylruthenium complexes at ambient temperature to give the desired [2+2+2] cycloadducts selectively. The synthesis of bicyclic pyridines was achieved by means of the Ru (II) -catalyzed cycloaddition of the 1, 6-diynes with electron-deficient nitriles or dicyanaides. Similarly, the cycloaddition with heterocumulenes such as isocyanates and isothiocyanates furnished bicyclic pyridones or thiopyran imines, respectively. The electron-deficient carbonyl group of some tricarbonyl compounds also participated in the cycloaddition with the 1, 6-diynes, but the expected 2H-pyran underwent electrocyclic ring opening to give rise to unsaturated carbonyl products.抄録全体を表示PDF形式でダウンロード (1383K) -
松原 公紀, 永島 英夫2005 年 63 巻 2 号 p. 122-133
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーHighly efficient catalytic reactions have been achieved via activation of Si-H bonds of organohydrosilanes by triruthenium carbonyl clusters bearing bridging acenaphthylene or azulene ligands. A ruthenium complex, (μ2, η2:η3:η5-acenaphthylene) Ru3 (CO)7 (1) catalyzes hydrosilylation of ketones and aldehydes in solution at room temperature to form the corresponding silyl ether in high yields. Prior activation of the catalyst by excess amounts of the hydrosilane results in dramatic increase of the catalytic activity. Application of the hydrosilylation catalyzed by preactivated 1 to the reduction of carboxylic acids and their derivatives has provided efficient preparative methods for silyl and alkyl ethers from esters, silyl ethers from carboxylic acids, and amines from amides, which are hardly achieved with other transition metal catalysts. The cluster 1 also behaves as an active catalyst for ring-opening polymerization of cyclic ethers and cyclic siloxanes and addition polymerization of vinyl ethers, which are induced by hydrosilanes. Spectroscopic analysis of the polymers obtained reveals existence of an organosilyl moiety at the end group, which is useful for further chemical transformation of the formed polymer. Isolation, characterization, and reactions of possible catalytically active species help discussion on the reaction mechanisms, in which a triruthenium hydridosilyl cluster is involved in the catalytic cycle.抄録全体を表示PDF形式でダウンロード (1901K) -
藤本 哲也, 山本 巖2005 年 63 巻 2 号 p. 134-143
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーCyclic phosphorus or sulfur ylides have a carbon atom adjacent to the phosphorus or sulfur atom other than the ylide carbon atom. The neutral carbon atom could be activated as a carbanion or another ylide after the initial reaction of the ylide. Novel synthetic methods using the two reactive positions in the cyclic ylides were developed. (Z)-Alkenylphosphine oxides generated by the Wittig reaction of a five-membered cyclic phosphonium ylide were converted to (Z)-γ, δ-unsaturated ketones via the Horner-Wittig reaction of the phosphinoyl carbanions. The reaction of the cyclic ylide with α, β-unsaturated ketones, esters, and thioesters provided cycloheptene derivatives via tandem Michael-Wittig reactions in which the ylide was regenerated on the other carbon atom. The similar tandem reactions of a five-membered cyclic oxosulfonium ylide gave cycloheptene oxide derivatives. Their novel tandem reactions of the cyclic ylides proceeded via rigid bicyclo [3.2.1] octane to result in a highly diastereoselective synthesis of the products.抄録全体を表示PDF形式でダウンロード (1482K) -
錦戸 條二, 吉田 彰宏2005 年 63 巻 2 号 p. 144-153
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーMethods used in organic synthesis and within the chemical industry as a whole in the 21st century aim to conform to the principles of green sustainable chemistry (GSC) and, from now on, the realization of GSC in the chemical industry will be an important task. Synthetic organic chemistry aims to establish waste-free and environmental-benign industrial processes using highly versatile Lewis acids. Although aluminum chloride, boron trifluoride, titanium tetrachloride, etc. are known as Lewis acids, they need to be used stoichiometrically or in excess to achieve high yield and high selectivity. Furthermore, they are rarely recovered and recycled. Thus, even though they are widely used industrially, these Lewis acids cause many unresolved problems, including the production of large amounts of wastes and the high consumption of energy. We attempted to develop highly active Lewis acid catalysts and to use these catalysts in GSC-type reaction processes. Our procedure was, first, to develop highly active Lewis acid catalysts, and then to meet the challenge of creating revolutionary organic reaction processes using fluorous solvents and water as reaction media. The key technological aim of the development was to achieve a “catalyst recycling system that utilizes the high activity and structural features of fluorous Lewis acid catalysts”.
We developed the novel fluorous Lewis acid catalysts, ytterbium (III), tin (IV), hafnium (IV) bis (perfluoroalkanesulfonyl) amide or tris (perfluoroalkanesulfonyl) methide catalyst. Our catalysts were effective and recyclable for Baeyer-Villiger reaction, direct esterification, and transesterification in fluorous biphasic system (FBS). The cyclodextrin copolymer-inclusion complex of our catalyst and the fluorous silica gel-supported catalyst were also effective and recyclable for Diels Alder reaction, Mukaiyama-aldol reaction and Baeyer-Villiger reaction in water.抄録全体を表示PDF形式でダウンロード (3307K) -
松原 誠二郎, 大嶌 幸一郎2005 年 63 巻 2 号 p. 154-161
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーAlkenes, alkanes, and polystyrene were converted into fully deuterium labelled ones by treatment with transition metal catalyst and deuterium oxide under hydrothermal condition. The simple method to get fully deuterium labelled compounds is easy to apply to various types of organic compounds.抄録全体を表示PDF形式でダウンロード (1444K) -
山本 芳彦, 山口 富男, 錦戸 條二, 松原 誠二郎2005 年 63 巻 2 号 p. 162
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (186K) -
第6回 有機合成化学協会関西支部2005 年 63 巻 2 号 p. 163-168
発行日: 2005/02/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (2375K)
- |<
- <
- 1
- >
- >|