AbstractHerein, we present an unprecedented azine‐limited C5−H polyfluoroarylation of 2‐aminopyridines enabled by a transient and electron‐deficient perfluoroaryl‐Pd species via C−H/C−H coupling. The protocol further allows C3(5)−H polyfluoroarylation of 2‐alkoxypyridines guided by sterics and electronics for the first time. The late‐stage C−H functionalization of drugs, drug derivatives, and natural product derivatives and synthesis of C5‐aryl drug derivatives further demonstrated the method's utility. The preliminary mechanistic studies reveal that the synergistic combination of the bulky yet electrophilic perfluoroaryl‐Pd species and the partial nucleophilicity of the C5‐position of 2‐amino/alkoxy‐pyridines is the origin of reactivity and selectivity. Importantly, the first experimental evidence for the role of diisopropyl sulfide is provided.
摘要在本文中,我们介绍了一种前所未有的偶氮限制的 2- 氨基吡啶的 C5-H 多氟芳基化反应,该反应通过 C-H/C-H 偶联由瞬时缺电子的全氟化芳基钯物种实现。该方案还首次实现了立体学和电子学指导下的 2-烷氧基吡啶的 C3(5)-H 多氟芳基化。药物、药物衍生物和天然产物衍生物的后期 C-H 功能化以及 C5 芳基药物衍生物的合成进一步证明了该方法的实用性。初步机理研究表明,笨重但亲电的全氟芳基钯物种与 2-氨基/烷氧基吡啶的 C5 位部分亲核性的协同组合是反应性和选择性的源泉。重要的是,实验首次证明了二异丙基硫醚的作用。