有機合成化学協会誌
Online ISSN : 1883-6526
Print ISSN : 0037-9980
ISSN-L : 0037-9980
68 巻 , 1 号
選択された号の論文の10件中1~10を表示しています
巻頭言
総説および総合論文
  • 高井 和彦
    2010 年 68 巻 1 号 p. 3-18
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    Development of nucleophilic organometallic species plays an important role in organic synthesis, especially for construction of carbon skeletons. This account describes the following synthetic reactions with novel organometallic species: (1) Preparation of alkenylchromium reagents for chemoselective addition to aldehydes, (2) Generation of geminal dimetallic species of zinc and chromium for the Wittig-type olefination, (3) Preparation of tantalum-alkyne complexes and their synthetic use, (4) Activation and deactivation of zinc with a catalytic amount of lead, (5) Control of one-electron transfer and its application to sequential radical and anionic reactions, (6) Rhenium and manganese catalyzed-Barbier-type addition of aromatic compounds to aldehydes based on C-H bond activation. The account focuses on the background to the research and how the reactions were discovered.
  • 荒井 孝義
    2010 年 68 巻 1 号 p. 19-32
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    The catalytic synthesis of chiral molecules is of crucial importance in fine chemistry in order to ensure the supply of useful and valuable organic compounds. The importance of this research topic has stimulated chemists worldwide to develop numerous methods of asymmetric catalysis, although the process of developing new catalysts involves tedious effort even when modern methods are used. One way to overcome the time-consuming aspect of the process would be to use the technology of combinatorial chemistry for the discovery and optimization of catalysts. For efficient exploration of novel asymmetric catalysts using the combinatorial approach, a convenient technology of high-throughput screening (HTS) is required for analyzing both catalytic activity (chemical yield) and enantiomeric excess.
       With the aim of investigating novel asymmetric catalysts using a library of chiral ligands, we have developed a new high-throughput screening (HTS) by coupling a circular dichroism (CD) detection with a reaction on solid-phase catalysts. Using the “solid-phase catalysis/CD-HTS”, several kinds of new asymmetric catalysts were discovered including an imidazoline-aminophenol-Cu catalyst. A novel catalytic asymmetric Friedel-Crafts/Henry reaction was successfully developed by the imidazoline-aminophenol-Cu catalyst to construct three contiguous acyclic stereocenters.
  • -[6-2+2]反応の開発-
    倉橋 拓也, 松原 誠二郎
    2010 年 68 巻 1 号 p. 33-40
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    A new synthetic strategy for heterocyclic compounds with transition metal-catalyzed reaction was developed. It was demonstrated that carbonyl moiety in a cyclic compound is susceptible to nucleophilic attack of nickel(0) complex, which allows an intermolecular formal [4+2] cycloaddition to alkynes via decarbonylation, decaroxylation or elimination of ketone. A nickel-catalyzed decarbonylative cycloadditon of N-arylphthalimides with alkynes affords substituted isoquinolones. A decarbonylative cycloaddition of phthalic anhydrides to alkynes is also successfully demonstrated using a nickel catalyst in association with a Lewis acid as a co-catalyst. A carboamination of alkynes with isatoic anhydrides to form quinolones is also achieved by a nickel-catalyzed decarboxylative cycloaddition. It is also demonstrated that a cycloaddition of salicylic acid ketal to alkyne using a nickel catalyst forms chromones through an elimination of a ketone.
  • 押木 俊之, 兵頭 功, 石塚 章斤
    2010 年 68 巻 1 号 p. 41-51
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    New bifunctional chemical catalysts for the hydration of nitriles are described. cis-Ru(acac)2(PPh2py)2 exhibited high activity, with a turnover frequency of up to 20,900 (mol of amide)/((mol of catalyst)h). Newly synthesized iridium complexes bearing a PPh2py ligand have a 16e- square planar structure. The catalytic hydration of nitriles proceeded at 80 °C within few hours to give corresponding amides in almost quantitative yield. Moreover, the iridium complexes acted as a catalyst for the hydration under solvent-free conditions. In addition, new catalysts based on palladium nanoparticles for the hydration are described. Copper compounds containing oxygen atom acted as effective co-catalysts in the catalytic system.
  • 横山 泰
    2010 年 68 巻 1 号 p. 52-63
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    The development of highly diastereoselective photochromic compounds that our group has carried out in the past 15 years is described here. Observations by 1H NMR of the enantiomeric isomerization of helically chiral hexatriene moiety of a fulgide which undergoes photochemical 6π-electrocyclization are first described, followed by discussions on the optical resolution of a fulgide and diastereoselective photochromism of an (R)-binaphthol-modified fulgide. A new concept of diastereoselective photochromism has also been realized by using diarylethenes as the template. The concept consists of: (i) Allylic 1,3-strain and (ii) electronic and steric repulsions between the oxygen atoms on a substituent on the stereogenic carbon atom attached to the ring-closing carbon atom located at one terminal of the hexatriene moiety and the heteroatom on the second heteroaromatic ring. Finally, a general strategy to achieve extraordinarily high diastereoselectivity of up to 100:0 has been demonstrated by the introduction of dual chiral stereocontrolling substituents to diarylethenes.
  • 久保 孝史, 清水 章弘, 中野 雅由, 中筋 一弘
    2010 年 68 巻 1 号 p. 64-74
    発行日: 2010年
    公開日: 2010/03/02
    ジャーナル 認証あり
    Main issue described in this article is clarification of spin-spin interactions in delocalized singlet biradical species, especially co-existence of intra- and inter-molecular interactions. For the end, we designed and prepared some singlet biradical molecules thermodynamically stabilized by utilizing spin-delocalizing character of phenalenyl radical. These species were found to be stable in air and could be isolated in a crystalline form. X-ray crystallographic analysis revealed the abnormally short π-π contact between molecules, suggesting a strong intermolecular spin-spin interaction, even though the species had a strong intramolecular spin-spin interaction. Co-existence of both the interactions led to lower energy shift of HOMO-LUMO absorption bands in a solid state with respect to solution bands. These findings indicate that covalent bonding character is operative within and between molecules in molecular aggregates of delocalized singlet biradicals. This new aspect was supported by variable-temperature X-ray crystallography and reflectivity measurement on single crystals which had one-dimensional π-π chains of the delocalized singlet biradicals, and we concluded that the electronic structure of the 1-D chain could be represented by the Resonating Valence Bond model proposed by Pauling.
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