AbstractWe herein describe a palladium‐catalyzed hydrocyanation of propiolamides for the stereodivergent synthesis of trisubstituted acrylonitriles. This synthetic method tolerated various primary, secondary and tertiary propiolamides. The cautious selection of a suitable ligand is essential to the success of this stereodivergent process. Control experiments indicate the intermediacy of E‐acrylonitriles, which lead to Z‐acrylonitriles via isomerization. The density functional theory calculations suggests that the bidentate ligand L2 enables a feasible cyclometallation/isomerization pathway for the E to Z isomerization, while the monodentate ligand L1 inhibits the isomerization, leading to divergent stereoselectivity. The usefulness of this method can be demonstrated by the readily derivatization of products to give various E‐ and Z‐trisubstituted alkenes. In addition, the E‐ and Z‐acrylonitrile products have also been successfully employed in cycloaddition reactions.
摘要我们在此介绍一种钯催化的丙炔酰胺氢氰化立体异构合成三取代丙烯腈的方法。这种合成方法可容忍各种伯、仲和叔丙炔酰胺。谨慎选择合适的配体对于这种立体发散工艺的成功至关重要。对照实验表明,中间产物为 E-丙烯腈,通过异构化生成 Z-丙烯腈。密度泛函理论计算表明,双齿配体 L2 可以为 E 到 Z 的异构化提供可行的环金属化/异构化途径,而单齿配体 L1 则会抑制异构化,从而导致立体选择性发散。这种方法的实用性体现在很容易对产物进行衍生,从而得到各种 E- 和 Z-三取代的烯烃。此外,E-和 Z-丙烯腈产物还被成功用于环化反应。