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68 巻, 6 号
選択された号の論文の12件中1～12を表示しています
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巻頭言
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吉田 潤一2010 年 68 巻 6 号 p. 591
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル オープンアクセスPDF形式でダウンロード (141K)
総説および総合論文
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塚野 千尋, Dionicio R. Siegel, Samuel J. Danishefsky2010 年 68 巻 6 号 p. 592-600
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありThis review focuses on total syntheses of garsubellin A, nemorosone and clusianone, which are polycyclic polyprenylated acylphloroglucinols (PPAPs). The PPAPs feature a highly oxygenated and densely substituted bicyclo[3.3.1]nonane core with prenyl, geranyl, and acyl side chains, and exhibit a wide range of biological activity, including cytotoxicity, antibacterial activity, HIV inhibitory activity, and antioxidant activity etc. These compounds have attracted the considerable attention of organic chemists due to fascinating chemical structures and intriguing biological activities. For total synthesis of this class compounds, several strategies were established and employed to construct a bicyclo[3.3.1]nonane core. Shibasaki-Kanai utilized stereoselective intermolecular aldol reaction, Claisen rearrangement and ring-closing metathesis. Danishefsky employed dearomative allylation, iodocarbocyclization, and bridgehead functionalization reactions. Simpkins and Marazano-Delpech used a Claisen-Deieckmann reaction with malonyl chloride. Porco group employed a double Michael reaction approach.抄録全体を表示PDF形式でダウンロード (1060K) -
本田 光典, 千木 昌人2010 年 68 巻 6 号 p. 601-613
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありThe silyl group acts as a directing group and a good leaving group in organic synthesis. We have been focusing on developing stereoselective synthesis utilizing these feature of silyl groups. In this context, stereoselective construction of multiple stereogenic centers using simple acylsilanes and transformation of cyclopropyl silyl ketones are described. The aldol-Tishchenko reaction of acylsilanes gives the corresponding 1,3-diol derivatives having three contiguous stereogenic centers with perfect levels of stereochemical control in one-pot. On the other hand, Mukaiyama aldol reaction of acylsilane silyl enol ethers derived from acylsilanes with dimethyl acetals affords the corresponding β-methoxyacylsilanes in high d.e.. The following 1,3-asymmetric induction in the nucleophilic addition furnished three diastereoisomers of 1,3-diol derivatives having the three contiguous stereogenic centers among four possible diastereomeric products with high stereoselectivity. Meanwhile, treatment of cyclopropylsilylmethanols derived from cyclopropyl silyl ketones with acid-catalyst gives the corresponding silyl-substituted homoallyl derivatives in high yields with good stereoselectivity. The protodesilylation of the resulting products proceeds with complete retention of the configuration.抄録全体を表示PDF形式でダウンロード (1002K) -
林 実2010 年 68 巻 6 号 p. 614-624
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありOrganophosphines play an important role in the field of organic synthesis, especially as ligands in transition metal catalysis. However, the synthesis of organophosphines with various functional groups still has many difficulties due to limitations in phosphorus-carbon bond formation. In this review, recent advances in the syntheses of organophosphines having various functional groups by using silylphosphines under mild conditions are described. Sterically protected silylphosphines are effectively applied to selective formations of several types of carbon-phosphorus bond, via three types of adequate activations; activation of a phosphorus-silicon bond of a silylphosphine by means of a fluoride, nucleophilic attack to the electrophile activated by a Lewis acid, and a transition-metal catalyzed activation of phosphorus-silicon bond. One successful application of a stepwise functional phosphine synthesis is also described.抄録全体を表示PDF形式でダウンロード (475K) -
梶川 敬之, 古市 紀之, 勝村 成雄2010 年 68 巻 6 号 p. 625-637
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありPeridinin is known as a representative auxiliary light harvesting pigment for photosynthesis in the sea. In the peridinin-chlorophyll (Chl) a-protein (PCP) complex, exceptionally high (>95%) energy transfer efficiencies from peridinin to Chl a has been reported. This energy transfer efficiency is thought to be related to the unique structure of peridinin, which possesses allene and ylidenbutenolide functions and the unusual C37 carbon skeleton referred to as a ‘nor-carotenoid’. There are, however, no studies on the subjects of why peridinin possesses a unique allene group and an irregular C37 skeleton, and how these functions play a role in the exceptionally high energy transfer. We have established the highly efficient synthesis of natural peridinin and successfully synthesized its allene and conjugated polyene modified derivatives. Measurements of their ultrafast time resolved spectra and Stark spectra have strongly suggested that these structural feature of peridinin has essentially contributed to its super ability of energy transfer.抄録全体を表示PDF形式でダウンロード (1209K) -
平谷 和久2010 年 68 巻 6 号 p. 638-648
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありCrownophanes which were used as rotor molecules in this review were prepared via tandem Claisen rearrangement (TCR). Primary amines having a bulky end group were also prepared to use as a part of axle molecules. Using crownophanes, a new method to prepare rotaxane systems has been developed. That is, we call it “a method via covalent bond formation”. This method contains two processes, esterification and aminolysis. The first step is the reaction of hydroxy group of macrocyclic compounds (crownophanes) with acid chloride, and the second step is the reaction of the ester produced with amine having a bulky end group. This method successfully gave [1]-, [2]-, and [3]rotaxanes in moderate yields. In the fluorescence spectrum, the efficient energy transfer from rotor molecules to end anthryl group of axle molecules was observed in the [n]rotaxanes. In the presence of lithium ion, the energy transfer occurred very efficiently, but not in the presence of other ions. Chiral recognition for phenylalaninol was also observed using achiral rotaxane having asymmetrical rotor and axle. We also reported that our rotaxanes could attach on the gold surface. We successfully observed the single rotaxanes by atomic force microscope. Thus, we report here that the rotaxane synthesis via covalent bond formation is successfully performed to give many kinds of rotaxanes starting from crownophanes which were prepared via TCR.抄録全体を表示PDF形式でダウンロード (1418K) -
福山 高英, 大村 倉平, 柳 日馨2010 年 68 巻 6 号 p. 649-658
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありIn this account, we focused on the high potentials of ruthenium hydride complexes, such as RuHCl(CO)(PPh3)3, as a multi-task catalyst for atom-economical C-C bond-forming reactions. In our initial work, we discovered that the dimerization of primary unsaturated alcohols to give α-hydroxymethyl ketones was promoted by RuHCl(CO)(PPh3)3. Some insights into the reaction mechanisms suggest that double bond-isomerization leading to aldehydes, transfer hydrogenation to give enals, formation of ruthenium enolates, aldol reactions of the enolates with aldehydes, and the subsequent β-hydride elimination are involved in the unusual dimerization. Taking advantages of the ability of transfer hydrogenation by RuHCl(CO)(PPh3)3, we developed reductive dimerization reaction of enals in the presence of secondary alcohols and cross-coupling reaction of enals with primary alcohols, both of which led to α-hydroxymethyl ketones. The regioselective addition of aldehydes to enones was also successful, which provides a useful entry to 2-alkyl-substituted 1,3-diketones. The ruthenium hydride-catalyzed cross-coupling reaction of dienes with aldehydes gave β,γ-unsaturated ketones in high yield with high regioselectivity. RuHCl(CO)(PPh3)3 is also an efficient catalyst for lactonization of both dialdehydes and keto aldehydes. The consecutive C-C and C-O bond forming reactions were achieved using enones and dialdehydes, which gave keto lactones in good yields.抄録全体を表示PDF形式でダウンロード (860K)
Review de Debut
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松岡 真一2010 年 68 巻 6 号 p. 659-660
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル オープンアクセスN-Heterocyclic carbene (NHC) has been widely used as a ligand for transition metal complexes and as an organocatalyst. Herein, the recent progress of synthetic polymer chemistry made by NHC is briefly reviewed. NHC serves as an efficient catalyst for ring-opening polymerization of cyclic esters and group transfer polymerization of (meth)acrylates. Living polymerization of ethylene oxide proceeds by NHC initiator. New polymeric materials such as dynamic covalent polymers and main chain organometallic polymers can be prepared from difunctional NHC.抄録全体を表示PDF形式でダウンロード (220K)
ケミカルズ覚え書き
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宮澤 賢一郎2010 年 68 巻 6 号 p. 661-664
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありPDF形式でダウンロード (525K)
ラウンジ
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中井 武2010 年 68 巻 6 号 p. 665-667
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありPDF形式でダウンロード (274K)
十字路
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塚野 千尋, 勝村 成雄, 福山 高英2010 年 68 巻 6 号 p. 668
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル オープンアクセスPDF形式でダウンロード (144K)
反応機構演習
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横島 聡2010 年 68 巻 6 号 p. 669-670
発行日: 2010/06/01
公開日: 2010/11/01
ジャーナル 認証ありPDF形式でダウンロード (148K)
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