著者

張 功幸 塩入 孝之 青山 豊彦

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.67, no.4, pp.357-368, 2009 (Released:2011-04-11)

被引用文献数

1 8

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This review describes the recent application of trimethylsilyldiazomethane (Me3SiCHN2, TMSCHN2), its lithium and magnesium bromide salts [TMSC(Li)N2 and TMSC(MgBr)N2] to the synthesis of heterocycles. Reaction of TMSCHN2 with acyl isocyanates followed by Diels-Alder reaction with propiolates or N-phenylmaleimide affords furans or bicyclic pyridones in a one-pot process, respectively. In addition, TMSCHN2 is useful for the preparation of 2-azaazulenes, aziridines and indolizines. Meanwhile, TMSC(Li)N2 reacts with benzynes generated from halobenzenes to yield 3-trimethylsilylindazoles, which are easily converted to 1-arylindazoles or indazoles bearing 3-hydroxymethyl units. TMSC(Li)N2 is also applicable to the synthesis of indoles, benzofurans, pyrroles, thiophenes and 2,3-benzodiazepines. By using TMSC(MgBr)N2, α-substituted β-trimethylsilyl-α,β-epoxyesters can be synthesized from α-ketoesters in a one-pot process. Reaction of TMSC(MgBr)N2 with carbonyl compounds efficiently furnishes trimethylsilylated diazoalcohols, which react with propiolates to give di- or tri-substituted pyrazoles.

著者

Takashi Ikawa Hiroaki Tokiwa Shuji Akai

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.70, no.11, pp.1123-1133, 2012-11-01 (Released:2012-12-05)

参考文献数

86

被引用文献数

7 17

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The silyl- and boryl-directed regiocontrol of benzyne reactions and their theoretical analyses using density functional theory (DFT) are described herein. The Diels-Alder reactions of both 3-silyl- and 3-borylbenzynes with substituted furans and the [3+2] cycloadditions of 3-silylbenzynes with 1,3-dipoles predominantly produced distal cycloadducts, whereas the [3+2] cycloadditions of the borylbenzynes exclusively produced proximal cycloadducts. Moreover, primary amines selectively underwent nucleophilic addition reactions at the more hindered ortho-position of the silyl group of the benzynes. The origin of these anomalous regiochemistries was theoretically evaluated using the natural bond orbital and reaction pathway analyses including the transition states of these reactions. On the basis of DFT calculations, it is proposed that the reactions of the borylbenzynes were controlled by the electrostatic effect of the boryl group, whereas those of the silylbenzynes were primarily governed by the steric effect of the silyl group.

著者

金井 求 松永 茂樹 生長 幸之助 清水 洋平

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.71, no.5, pp.433-442, 2013-05-01 (Released:2013-06-12)

参考文献数

63

被引用文献数

2

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In general, biologically active drug lead molecules are structurally complex, bearing multiple functional groups and chiral sp3 carbons. Our aim in developing new catalysis is to promote a concise, robust, and clean drug lead synthesis. To do so requires catalysis allowing for the design of concepually new retrosynthesis independent of functional groups. Here we summarize our first step toward such a goal. First, we describe a Cu(I)-catalyzed enantioselective condensation of ketones and hemiaminals that can produce versatile chiral building blocks for alkaloid synthesis. The hard anion-conjugated soft metal (HASM) catalysis concept is the basis for the reactivity. Second, two Cu-catalyzed cross-dehydrogenative coupling (CDC) reactions are discussed. The radical-conjugated redox catalysis (RCRC) concept leads to the development of a very early example of catalytic asymmetric aerobic CDC. Third, the Rh-catalyzed aldehyde cross aldol reaction and the Co-catalyzed C-4 selective alkylation of pyridines, both of which are mediated by means of hydride transfer, are described. Unique reactivity in the latter two topics is partly due to the redox activity of the transition metal catalysts.

著者

飛鋪 靖

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.32, no.12, pp.971-988, 1974-12-01 (Released:2009-11-13)

参考文献数

118

被引用文献数

1 3

著者

福山 愛保 江角 朋之

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.65, no.6, pp.585-597, 2007-06-01 (Released:2010-10-20)

参考文献数

37

被引用文献数

9 17

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Plants producing natural products remain one of the few sources of drug discovery, yielding unorthodox and often unexpected chemical structures. Since some classes of plant-derived natural products are frequently concentrated on the same genus, the extensive chemosystematic studies of the specific plants serve as a chemical library to discover candidates for drugs or biological probes for physiological studies. Vibsane-type diterpenes belong to rarely occurring natural products since they have been elaborated solely in Viburnum species such as V. awabuki, V odoratissimum, and V. suspensum. These diterpenes are further classified into 11-membered ring, 7-membered ring and rearranged (neovibsanin) types, thus putting their chemical diversity into a unique chemical library. We describe a variety of vibsanes, chemical correlations between three subtypes, and synthetic studies of vibsanin F, the simplest 11-membered ring vibsane, as well as neurotrophic activities of neovibsanins A-B.

著者

今村 寿一 青葉 千春 小島 邦彦

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.45, no.9, pp.909-913, 1987-09-01 (Released:2009-11-13)

参考文献数

60

被引用文献数

1 4

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Tetramethylammonium hydroxide (TMAH) is a relatively strong base among organic compounds, and decomposes at 130-140°C into gaseous substances (Me3N, Me2O, MeOH, and H2O). TMAH has been prepared by alkali treatment of tetramethylammonium chloride (TMAC) obtainable from trimethylamine and methyl chloride, but use is made recently of developer electrolysis of TMAC in the presence of ion exchange membrane. The latter method gives rise to a highly pure TMAH aqueous solution free from chloride anions. TMAH currently finds some utilities in the production of highly functional materials such as developer for positive-working photoresist and the surface treatment of fibers, glasses, and plastics, and also as reagent for the methyl esterification of fatty acids and phospholipids, reagent for organic synthesis and preparation of catalysts, etc.

著者

太田 暢人

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.15, no.3, pp.121-128, 1957 (Released:2010-10-20)

参考文献数

25

著者

平間 正博

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.41, no.5, pp.418-431, 1983

被引用文献数

3

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Convergent and enantiospecific syntheses of compactin (1 a) and mevinolin (1 b), potent competitive inhibitor of HMG-CoA reductase, have been achieved via asymmetric intramolecular Diels-Alder reaction of acyclic (<I>E, E, E</I>) -trienone 4 leading to <I>trans</I>-octalone 3, a common intermediate for congeners. Chirality of C13 in 4 was designed to induce the four asymmetric centers with desired configuration by this reaction : the chirality controlled the approach of the dienophile from a single diastereotopic face. Trienone 4 was expeditiously constructed by the combination of two segments 5 and 6. Enantio- and stereo-specific synthesis of 6, a chiral 1, 3, 5- triol derivative, rested on the two novel methodologies, <I>i.e</I>, the convenient asymmetric reduction of β-keto carboxylate 19 d with baker's yeast and the regio- and stereo-selective iodofunctionalization (1, 3-asymmetric induction) of homoallylic carbamate. Preparation of 5 in its optically active form was accomplished by the elaboration of readily available γ-lactone 12.

著者

高橋 孝志

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.67, no.7, 2009-07-01

著者

有機合成化学協会

出版者

有機合成化学協会

巻号頁・発行日

1943