Synthesis of C—N Axial Chirality <scp><i>N</i>‐Arylindoles</scp> via Pd(<scp>II</scp>)‐Catalyzed Free <scp>Amine‐Directed</scp> Atroposelective C—H Olefination<sup>†</sup>
Lei Wang, Wen‐Kui Yuan, Zhen‐Kai Wang, Jun Luo, Tao Zhou, Bing‐Feng Shi
Abstract
Comprehensive Summary Axially chiral N ‐arylindoles bearing a stereogenic C—N axis are unique important scaffolds in natural products, advance materials, pharmaceuticals and privileged chiral ligands or catalysts. Herein, we report the direct synthesis of C—N axially chiral N ‐arylindoles through a Pd‐catalyzed free amine‐directed atroposelective C—H olefination enabled by a spiro phosphoric acid (SPA) ligand. A wide range of enantioenriched N ‐aromatic amine indoles were obtained in high yields with good enantioselectivities (35 examples, up to 91% yield and up to 96% ee). The chiral products with free amine group offer an effective functional handle for down‐stream diversity‐oriented synthesis.