Harnessing the Reactivity of Alkyne by Cu‐Catalyst: Assembly of Highly Functionalized Five‐Membered N‐Heterocycles

Copper‐catalyzed activation of alkynes has gained considerable attention as a robust and versatile strategy for the synthesis of nitrogen‐containing medium‐ring heterocycles. These important structures, which include compounds such as pyrroles, pyrrolidinones, and pyrrolidines, serve as essential building blocks in a wide range of pharmaceuticals, agrochemicals, and biologically active products. They can be synthesized through various cyclization or annulation methods. The ability of copper catalysts to effectively activate alkynes allows for the formation of CN and CC bonds under relatively mild and operationally simple conditions, ensuring high selectivity and tolerance to different functional groups. This review provides a comprehensive overview of Cu‐catalyzed methods for producing five‐membered N‐heterocycles, presenting a flexible and sustainable pathway to complex structures. The article is divided into sections covering pyrroles, pyrrolidinones, and pyrrolidines, highlighting future applications, advancements, and mechanistic insights. It aims to enhance readers’ understanding of the reaction mechanisms and how important the appropriate starting materials are for each catalytic process.