巻号一覧
58 巻, 6 号
選択された号の論文の8件中1～8を表示しています
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大熊 健太郎2000 年 58 巻 6 号 p. 548-555
発行日: 2000/06/01
公開日: 2010/01/22
ジャーナル フリーTriphenylvinylphosphonium salts were prepared by the reaction of triphenylphosphine with epoxide and acid, followed by the addition of acetyl chloride in one pot operation. These salts were also synthesized by the reaction of 2-hydroxyalkyltriphenylphosphonium salts with acetyl chloride or oxalyl chloride. Other synthetic methods of these salts were also described. Optically active 3-hydroxyalkyl triphenyl phosphonium salts were synthesized by the reaction of phospho-rus ylides with epoxides. The reaction of these salts with 2 eq of BuLi gave the corresponding γ-oxidephosphonium ylides, which further reacted with aldehydes to give the corresponding E-rich homoallylic alcohols. 2, 2, 2-Tripheny1-1, 2λ5-oxaphospholanes were easily prepared by the reaction of 3-hydroxylalkylphosphonium salts with sodium hydride. The reaction with aldehydes afforded Z-rich homoallylic alcohols almost quantitatively. Thus, high selectivity for Z- or E-homoallylic alcohols was available depending on the particular circumstances. The syntheses of optically active methylenecyclopropylacetic acid and recifeiolide were succeeded by this method.抄録全体を表示PDF形式でダウンロード (926K) -
棚谷 綾, 東屋 功, 影近 弘之2000 年 58 巻 6 号 p. 556-567
発行日: 2000/06/01
公開日: 2010/01/22
ジャーナル フリーAromatic secondary amides such as benzanilide (1) exist in trans-amide form both in the crystal and in solution, whereas N-methylbenzanilide (2) exists in cis form in the crystal, and predominantly in cis form in various solutions. Similar cis conformational preferences were observed in the aromatic N, N'-dimethylated urea (4) and guanidine (7), in which two aromatic rings are located face-to-face. The cis conformations of N-methylated amides, ureas and guanidines could be utilized to construct interesting aromatic architecture. First, N, N', N″-trimethyl-N, N', N″-triphenyl-1, 3, 5-benzenetricarboxamide (12) and a cyclic triamide 14 have crystal structures in which three N-phenyl groups exist with the same orientation (syn conformation). Second, several aromatic amides which have no fixed asymmetric center afforded chiral crystals by simple recrystallization. In the case of 1, 2-bis (N-benzoyl-N-methylamino) benzene (18), two enantiomeric crystals could be distinguished morphologically or on the basis of symmetrical CD spectra in KBr, and by 1H-NMR in the presence of chiral 1, 1'-bi-2-naphthol. Third, aromatic multi-layered structures could be constructed by using N, N'-dimethylated urea or guanidino bonds. These unique layered structures could be applied to obtain aromatic molecules with potent DNA-binding ability.抄録全体を表示PDF形式でダウンロード (1847K) -
不斉修飾ニッケル (MNi) の立体化学をもとにした研究の展開田井 晰2000 年 58 巻 6 号 p. 568-577
発行日: 2000/06/01
公開日: 2010/01/22
ジャーナル フリーAlmost perfect enantio-differentiating hydrogenation was achieved by heterogeneous catalyst. Tartaric acid-NaBr modified supersonicated Raney nickel (TA-NaBr-MRNiU) showed 98.6% of e.d.a. in the hydrogenation of methyl 3-cyclopropyl-3-oxopropanoate. Three emprical modeles; “catalyst region model”, “reaction process model”, and “stereochemical model”, proposed for the explanation of the functions of MNi enable us to design the present reaction system. The development of the models and their contribution for the improvement of the catalyst and its reaction system are described.抄録全体を表示PDF形式でダウンロード (1597K) -
三浦 雅博, 野村 正勝2000 年 58 巻 6 号 p. 578-586
発行日: 2000/06/01
公開日: 2009/11/13
ジャーナル フリーArylation and aroylation reactions of unsaturated compounds, including alkenes and alkynes, catalyzed by transition metal complexes are powerful methods for preparing aromatic fine compounds. While the reactions with palladium catalysts are well documented and widely employed, those using rhodium species are less common. A number of unique and efficient rhodium-catalyzed reactions of several aromatic substrates, such as aroyl chlorides, aromatic acid anhydrides, arylboronic acids, arylstannanes, functionalized aromatic compounds, and aromatic aldehydes, with unsaturated compounds have, however, been developed in recent years. In this review are summarized the novel methods.抄録全体を表示PDF形式でダウンロード (1286K) -
徳永 信, 若槻 康雄2000 年 58 巻 6 号 p. 587-596
発行日: 2000/06/01
公開日: 2009/11/13
ジャーナル フリーAdditions to C-C multiple bonds are simple and the most efficient methods in organic synthesis in terms of atom utilization due to avoidance of stoichiometric amounts of by-products. The following catalytic C-C, C-O and C-N bond-constructions by direct additions of nucleophiles to alkynes catalyzed by ruthenium complexes have been developed. 1) Dimerization of terminal alkynes to 1, 4-disubstituted butatriens which is an unusual tail-to-tail coupled product. 2) The first example of anti-Markovnikov hydration of terminal alkynes to aldehydes. 3) Intermolecular hydroamination of terminal alkynes with anilines to imines. Some of the reactions proceed in high yields under solvent-free, open-air conditions. Theoretical studies were also performed about transformation of η2-coordinated 1-alkynes to vinylidene complexes which plays important role in regioselectivity of the addition reactions.抄録全体を表示PDF形式でダウンロード (1468K) -
柳田 玲子, 井深 俊郎2000 年 58 巻 6 号 p. 597-605
発行日: 2000/06/01
公開日: 2009/11/13
ジャーナル フリーThe chemistry of metallic samarium (Sm) is of current interest in organic synthesis. Though samarium iodide (SmI2) is a good synthetic tool (a mild, neutral and ether-soluble one-electron reductant), its sensitivity to air makes it rather difficult to handle. We have been studying the reactivity of Sm to overcome this drawback of SmI2. Dehalogenation of vic-dihalides with Sm gave alkenes and alkynes. These reductions were accelerated with a catalytic amount of acid. Olefinic double bonds of various α, β-unsaturated carboxylic acid derivatives (ester, amide, nitrile, carboxylic acid) were also reduced to give the corresponding 1, 4-reduction products. Aromatic carbonyl compounds were reduced to the corresponding pinacol coupling products with Sm-I2 or Sm-I2-Ti (OiPr) 4 in methanol. Meso isomers were mainly produced in the presence of Ti (OiPr)4 Acyl- or alkoxycarbonyl-protected alcohols or amides are deprotected easily and selectively under mild and neutral conditions. Stereoselective allylation and dimerization of optically active imines with Sm and a catalytic amount of I2 have been successfully accomplished. Both Barbier-type allylation and intermolecular pinacol-like coupling reaction of imines were carried out smoothly to give allylation products and C2-2, 2'-ethylenediiminodiethanol derivatives in a highly diastereoselective manner. This novel C2-dimeric amino alcohols bearing primary alcohols catalyzed enantioselective addition of diethylzinc to aldehydes.抄録全体を表示PDF形式でダウンロード (1351K) -
創製研究者の回想利部 伸三2000 年 58 巻 6 号 p. 606-610
発行日: 2000/06/01
公開日: 2009/11/13
ジャーナル フリーイミダクロプリドは1991年に上市されて以来現在76国に登録され, 1998年には6億USドルと世界最大の売り上げを記録した殺虫剤である。一方カルプロパミドは1998年に上市された稲いもち病防除剤である。筆者は企業の研究所において7年間農薬創製研究に携わる機会を得て, 表題の2薬剤を最初に合成する幸運に恵まれた。本稿は大学で合成有機化学を学んだ一人が企業で未経験の分野に足を踏み入れ, 商品化合物の発見に至った道のりを回想したものである。両薬剤に関する詳細な構造活性相関, 作用機構や応用に関しては総説を参照していただきたい。なお筆者がすべての賞に含まれているわけではないが, イミダクロプリドの発明・研究に対しては, 日本農薬学会賞 (技術), 同 (研究), 全国発明特別賞, 大河内賞, アメリカ化学会賞等, カルプロパミドに対しては日本農薬学会賞 (技術) 等が与えられている。抄録全体を表示PDF形式でダウンロード (844K) -
田井 晰, 三浦 雅博, 徳永 信, 利部 伸三2000 年 58 巻 6 号 p. 611
発行日: 2000/06/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (197K)
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