Diels-Alder反应中的次级轨道效应

Secondary orbital interaction in Diels-Alder reaction

利用概念密度泛函理论下的局域软度和广义局域软度,结合局域硬软酸碱(HSAB)原理,研究环戊二烯与CH2=CHCOCnH2n+1之间的Diels-Alder反应的立体选择性,其中活性因子均是由ABEEMσπ模型获得.与以往不同的是,除了将主要参与反应的4个原子作为反应中心之外,还将产生次级轨道效应(SOI)的2个原子也作为参与反应的一部分.得到的结果表明,所有反应的立体选择性均与实验结果取得了很好的一致性,由此提出了一种定量快速处理包含次级轨道效应的Diels-Alder反应的立体选择性的方法.

The stereoselectivity of Diels-Alder reactions between cyclopentadiene and substituted ethene CH2=CHCOCnH2n＋1 was investigated by the local softness and the generalized one combined with the local HSAB principle in the concept density functional theory, where the reactivity descriptors were obtained from ABEEMσπ model. We took not only the four reactive atoms as the reaction centers, but also the two atoms produced secondary orbital interaction （SOI） as the part of the reaction. The calculated results indicate that the stereoselectivities of all reactions are in agreement with the experimental results. Hence, we can conclude that a useful method was produced, which can quickly and quantitatively deal with the stereoselectivity of Diels-Alder reaction including the SOl.