Silver(I)-Catalyzed Conia-Ene Reaction: Synthesis of 3-Pyrrolines via a 5-endo-dig Cyclization

A novel method has been developed for the synthesis of 3-pyrrolines from -ketopropargylamines via a 5-endo-dig carbocyclization. This transformation involves a silver-catalyzed Conia-ene type reaction tolerating broad substrate scope with good to excellent yields. Furthermore, this methodology has been extended for the construction of 2-substituted pyrroles under base-mediated conditions.