AbstractOne of the most challenging tasks in organic synthesis is to develop novel methodologies for rapid construction of complex molecules starting from easily available yet inert raw materials. In this context, multi‐catalysis strategies have attracted great attention in the discovery of new reactivity profiles that may allow access to many difficult or unattainable transformations. So far the deoxygenative functionalization of ubiquitous amides is usually achieved by nucleophilic attack on the imine or iminium ion intermediate formed via activation of the C=O bond, and these functionalization reagents were often confined to C‐based nucleophiles, which largely limited the diversity of the resultant amines. Herein, we disclose a combined strategy of relay and cooperative catalysis with a triple iridium‐photoredox‐organocatalysis system to achieve an unprecedented reductive boration of amides, affording valuable α‐amino boron products which are viable building blocks. In this transformation, the Ir‐catalyzed semi‐reduction of amides is successfully incorporated with photo‐organic catalyzed nucleophilic boryl radical addition, thus delivering the corresponding α‐boryl amines in high efficiency.
摘要 有机合成领域最具挑战性的任务之一是开发新型方法,以便从易于获得的惰性原料出发,快速构建复杂分子。在这种情况下,多催化策略在发现新的反应性概况方面引起了极大的关注,这些反应性概况可能允许进行许多困难或无法实现的转化。迄今为止,无处不在的酰胺的脱氧官能化通常是通过亲核攻击 C=O 键活化形成的亚胺或亚铵离子中间体来实现的,而这些官能化试剂通常仅限于 C 型亲核物,这在很大程度上限制了所生成胺的多样性。在此,我们揭示了一种接力催化和协同催化的组合策略,利用三重铱-光氧化-有机催化系统实现了前所未有的酰胺还原丁化,得到了有价值的α-氨基硼产物,这些产物是可行的构筑基块。在这一转化过程中,铱催化的酰胺半还原与光催化的亲核硼酸基加成成功地结合在一起,从而高效地得到了相应的α-硼酸胺。