Palladium-Catalyzed Nucleophilic Substitution/C–H Activation/Aromatization Cascade Reaction: One Approach To Construct 6‑Unsubstituted Phenanthridines

A facile and practical palladium-catalyzed nucleophilic substitution/C–H activation/aromatization cascade reaction has been developed. A range of 6-unsubstituted phenanthridines could be obtained in moderate to good yields (31–85%) with readily prepared N-Ms arylamines and commercially available 2-bromobenzyl bromide derivatives as starting materials. The potential application of the protocol was also demonstrated by the expeditious synthesis of the natural alkaloid trisphaeridine.