• 제목/요약/키워드: Propargylation

검색결과 4건 처리시간 0.017초

Pd-Catalyzed Substitution Reactions with Organoindium Reagents in situ Generated from Indium and Allyl or Propargyl Halides

  • Lee, Phil-Ho;Shim, Eun-Kyong;Lee, Koo-Yeon;SeoMoon, Dong;Kim, Sun-Dae
    • Bulletin of the Korean Chemical Society
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    • 제26권1호
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    • pp.157-160
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    • 2005
  • Allylindium and propargylindium reagents in situ generated from the reactions of indium with allyl halides and propargyl halides could participate as nucleophiles in Pd-catalyzed substitution reactions of allyl carbonates to produce 1,5-dienes and 1,5-enynes in good yields. $\beta$-Hydride elimination products were produced in case of carbonates having $\beta$-hydrogens. Because organoindium reagents obtained from allyl or propargyl halides and indium have previously not been used to Pd-catalyzed allylic and propargylic substitution reactions, these results should provide more opportunities for the development of new C-C bond forming reactions.

Regulation of Stereoselectivity and Reactivity in the Inter- and Intramolecular Allylic Transfer Reactions

  • Yu, Chan-Mo;Youn, Jin-soup;Jung, Hee-Keum
    • Bulletin of the Korean Chemical Society
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    • 제27권4호
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    • pp.463-472
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    • 2006
  • The preparation of enatiomerically enriched homoallylic alcohols through asymmetric addition of chiral allylic transfer reagents and allylating reagents with chiral catalysts to the carbonyl functionalities represents an important chemical transformation. Excellent progress has been made over past decade in the development and application of catalytic asymmetric allylic transfer reactions. In this account, our efforts for the various intermolecular allylic transfer reactions such as allylation, propargylation, allenylation, and dienylation utilizing accelerating strategy and sequential allylic transfer reactions to achieve multiple stereoselection mainly using transition metal catalysts are described.

Indium and Gallium-Mediated Addition Reactions

  • Lee, Phil-Ho
    • Bulletin of the Korean Chemical Society
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    • 제28권1호
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    • pp.17-28
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    • 2007
  • Indium and gallium have emerged as useful metals in organic synthesis as a result of its intriguing chemical properties of reactivity, selectivity, and low toxicity. Although indium belongs to a main metal in group 13, its first ionization potential energy is very low and stable in H2O and O2. Therefore, indium-mediated organic reactions are of our current interest. On the basis of these properties of indium, many efficient indium-mediated organic reactions have been recently developed, such as the addition reactions of allylindium to carbonyl and iminium groups, the indium-mediated synthesis of 2-(2-hydroxyethyl)homoallenylsilanes, the indiummediated allylation of keto esters with allyl halides, sonochemical Reformatsky reaction using indium, the indium-mediated selective introduction of allenyl and propargyl groups at C-4 position of 2-azetidinones, the indium-mediated Michael addition and Hosomi-Sakurai reactions, the indium-mediated β-allylation, β- propargylation and β-allenylation onto α,β-unsaturated ketones, the highly efficient 1,4-addition of 1,3-diesters to conjugated enones by indium and TMSCl, and the intramolecular carboindation reactions. Also, we found gallium-mediated organic reactions such as addition reactions of propargylgallium to carbonyl group and regioselective allylgallation of terminal alkynes.