Controllable Pd-Catalyzed Allylation of Indoles with Skipped Enynes: Divergent Synthesis of Indolenines and N-Allylindoles

An unprecedented acid- and ligand-controlled divergent allylation of indoles with unactivated skipped enynes via Pd hydride catalysis has been disclosed. This redox-neutral transformation went through multiple hydropalladation insertion, β-hydrogen elimination, π–σ–π isomerization, and allylic substitution steps. This method not only provides a platform for synthesizing indolenines and N-allylindoles but also allows facile access to functional 1,3-dienes with high atom and step economy.