Mechanistic insight into the regioselective palladation of indole derivatives: Tetranuclear indolyl palladacycles with high C2-Pd or C3-Pd bond selectivity

This research provides a straightforward understanding of the regioselective palladation of indole derivatives by capturing both C2-Pd and C3-Pd intermediates of N-phenylindole and N-methylindole. Those tetranuclear indolyl palladacycles suggest that the regioselectivity of palladation depends on the N-substituted protective groups of indoles as well as the acidity of the reaction medium.