Three-Component, One-Pot Sequential Synthesis of Functionalized Cyclazines: 3<i>H</i>‑1,2a¹,3-Triazaacenaphthylenes

An efficient tandem route to the synthesis of 3H-1,2a1,3-triazaacenaphthylene derivatives of the cyclazine family has been developed. Target compounds were obtained in moderate to good yields by a Yb­(OTf)3/Ag2CO3-catalyzed, three-component domino reaction. This in turn will set the stage for a wide application of this useful reaction for the synthesis of structurally diverse polyheterocyclic skeletons containing the imidazo­[1,2-a]­pyridine privileged structure.