Copper(I)‐Catalyzed CuAIAC/Allylation Cascade: Modular Synthesis of Fully Substituted Allyl N,N′ ‐Bicyclic Pyrazolidinones

ABSTRACT A copper(I)‐catalyzed CuAIAC/allylation cascade reaction exploiting alkynes, azomethine imines, and allyl bromides has been developed for providing rapid access to fully substituted allyl N,N ′‐bicyclic pyrazolidinones, involving the formation of C(sp 2 )–C(sp 3 ) bond. The interception of the in situ generated cuprate‐pyrazolidinonate intermediate with allyl bromide plays a crucial role in the success of the reaction. In addition, scale‐up synthesis and late‐stage modification of bioactive complex molecules could be achieved. This method also features in complete regioselectivity, broad functional group compatibility, and mild reaction conditions.