Remote Construction of Diverse Heteropolycycles via 1,4‐Pd or 1,4/1,5‐Pd Migration‐Mediated Intermolecular Double C–H Annulation

Comprehensive Summary Although 1,4‐Pd migration has been widely used for the functionalization of remote C−H bonds, intermolecular double C−H annulation via this strategy remains elusive. Furthermore, catalytic reactions involving 1,5‐Pd migration are scarce due to competitive reductive elimination pathway. Herein, we report an intermolecular double C–H annulation of N ‐(2‐bromophenyl)‐2‐phenylacrylamides with 1, n ‐diynes mediated by 1,4‐Pd or sequential 1,4/1,5‐Pd migrations. The reaction proceeds through sequential Heck cyclization, alkyl‐to‐aryl 1,4‐Pd migration (or alkyl‐to‐aryl 1,4‐Pd migration followed by aryl‐to‐aryl 1,5‐Pd migration), dual alkyne insertion, and C–H activation, providing efficient access to both indolinone‐substituted tricyclic frameworks and tetracyclic indolinones. The method exhibits excellent regioselectivity, and preliminary mechanistic studies support the proposed pathway.