Intramolecular .pi.-Stacking and Asymmetric Induction: A Semiempirical Theoretical Study
Intramolecular .pi.-Stacking and Asymmetric Induction: A Semiempirical Theoretical Study
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分子内π-堆积和不对称诱导：半经验理论研究
DOI：
10.1021/jo00083a020
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发表时间：
1994
影响因子：
3.6
通讯作者：
C. Giessner
中科院分区：
文献类型：
--
作者：
J. Maddaluno;N. Gresh;C. Giessner
几种取代环己酯的构象参与了高度非对映选择性的有机反应，并通过分子内π堆积网络，借助于半经验的SIBFA程序进行了研究。研究了具有大量手性助剂的实验结果的不同情况。对于基于环己基的不对称巴豆酸酯和乙醛酸酯，空间要求很高的面对面“堆积”构象的稳定性如预期的那样随着分散能量贡献的绝对值的增加而增加。我们报告了与其他可能的构象相比，堆积构象的实验值和稳定性之间的良好相关性。
The conformations of several substituted cyclohexyl esters involved in highly diastereoselective organic reactions that have been rationalized by intramolecular π-stacking nvere investigated by resorting to the semiempirical SIBFA procedure. Different cases, for which experimental results featuring a large set of chiral auxiliaries are available, were studied. For the cyclohexyl-based asymmetric crotonates and glyoxylates, the stabilization of the sterically demanding face-to-face «stacked» conformers increases, as expected, with the absolute value of the dispersion energy contribution. We report a good correlation between the experimental de and the stability of the stacked conformer over the other possible ones