In this work, we describe a new goldcatalyzed oxidative cascade cyclization of conjugated enynamides. The reaction could be carried out under relatively mild condition. In presence of a cationic gold catalyst bearing an N-heterocyclic carbene ligand, enynamides derived from tryptamine react with pyridine N-oxide, leading to the formation of a variety of tetracyclic spiroindolines in a stereoselective manner.

Tricyclic ring systems possessing a dibenzo structure joined to a seven‐membered heterocyclic ring frequently show important biological activities. However, a modular approach to these molecules based on efficient intermolecular reaction of readily available chemicals is lacking. Herein, an unprecedented palladium‐catalyzed formal [4+3] annulation for modular construction of these tricyclic systems is described. This reaction features easily accessible reactants (o‐haloarylaldehydes and N‐tosylhydrazones), broad substrate scope, and excellent functional group compatibility. The synthetic potential is demonstrated by the easy scale‐up reactions, late‐stage modification of complex molecules, and collective synthesis of bioactive molecules and approved drugs.