• Title/Summary/Keyword: Endo/Exo selectivity

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Origin of Exo/Endo Selectivity in the Intramolecular Diels-Alder Reaction

  • Yan, Shihai;Ryu, Do-Hyun;Lee, Jin-Yong
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2527-2530
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    • 2010
  • The stereoselectivity of the intramolecular Diels-Alder reactions of 1 and its derivatives were investigated by ab initio calculations. The stereoselectivity mainly originates from the steric repulsion and the orbital interactions. The additional s-cis and s-trans conformations by introducing the carbonyl group at the neighbor of diene or dienophile may change the stereoselectivity, hence this kind of substitution can be utilized for stereoselectivive asymmetric synthesis.

Theoretical Studies on the Diels-Alder Reactions between Cyclopentadiene and Conformationally Flexible Dienophiles (시클로 펜타디엔과 구조적으로 회전이 쉬운 Dienophile간의 Diels-Alder 반응에 대한 이론적 연구)

  • Kim, Chan Kyung;Lee, In Young;Lee, Bon Su;Lee, Ik Choon;Kim, Kwan Soo;Joo, Young Hyup
    • Journal of the Korean Chemical Society
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    • v.40 no.7
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    • pp.483-491
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    • 1996
  • Dieis-Alder reaction between cyclopentadiene and 5-membered ring compounds which have exo-cyclic double bond has been studied using the PM3 method. Transition states do not show large geometrical change with the variation of dienophiles. Two isomers are possible due to the rotation of the exo-cyclic double bond of a dienophile. The reactivity for the formation of different products are explained using the FMO energy gap. The exo and endo selectivity of the reaction has been also studied from the correlation between the deformation energy and the activation barrier. Minimum energy reaction path is discussed using the Curtin-Hammett principle.

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