Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
J Am Chem Soc. 2022 May 11;144(18):8389-8398. doi: 10.1021/jacs.2c03411. Epub 2022 Apr 28.
Enantioselective transformations of olefins are among the most important strategies for the asymmetric synthesis of organic compounds. Chemo-, diastereo-, and stereoselective control of reactions with internal acyclic alkenes for the construction of functionalized acyclic alkanes still remain a persistent challenge. Here, we report a palladium-catalyzed asymmetric regiodivergent Heck-type diarylation of internal acyclic alkenes. The 1,2-diarylation of two accessible acyclic alkenes, cinnamyl carbamates and enamides with diazonium salts and aromatic boronic acids, furnishes products containing vicinal stereogenic centers via the stereospecific formation of carbonyl coordination-assisted transient palladacycles. Moreover, the asymmetric migratory diarylation of enamides enables the formation of incontiguous stereocenters by an interrupted diastereoselective 1,3-chain-walking process. This protocol streamlines access to highly functionalized multisubstituted enantioenriched carbamates and amine derivatives which are embedded in the key biologically active motifs.
烯烃的对映选择性转化是有机化合物不对称合成最重要的策略之一。对于构建功能化无环烷烃的内部无环烯烃反应的化学选择性、非对映选择性和立体选择性控制仍然是一个持续的挑战。在这里，我们报告了钯催化的内部无环烯烃的不对称区域发散型 Heck 型二芳基化反应。两个易得的无环烯烃肉桂基氨基甲酸酯和烯胺与重氮盐和芳基硼酸的 1,2-二芳基化，通过羰基配位辅助的瞬态钯配合物的立体特异性形成，提供了含有毗邻立体中心的产物。此外，烯胺的不对称迁移二芳基化通过中断的非对映选择性 1,3-链行走过程，能够形成不连续的立体中心。该方案简化了高度功能化的多取代手性富集氨基甲酸酯和胺衍生物的获取，这些化合物嵌入在关键的生物活性基序中。
