Transition Metal‐Catalyzed Amination of Ynamides with Azides through α ‐Imino Metal Carbenes

Comprehensive Summary Transition metal‐catalyzed amination of ynamides is an important protocol for the generation of α ‐imino metal carbenes, and various carbene‐type transformations have been achieved using alkynes as starting materials. This review summarizes the recent advances in the transition metal‐catalyzed amination of ynamides with azides via α ‐imino metal carbene intermediates, including gold and copper carbenes. Therefore, diverse functionalization reactions have been developed to realize the preparation of N‐containing products, such as formal annulation, X–H functionalization, carbene metathesis and other asymmetric reactions. These transformations are highlighted by presenting the reaction mechanism, selectivity, product diversity, and application. Key Scientists For the transition metal‐catalyzed amination of ynamides with azides, in 2005, Toste et al. firstly developed a gold‐catalyzed amination of alkynes using azides as nitrogen transfer reagents through α ‐imino gold carbene intermediates. In 2014, Ohno et al. disclosed a gold‐catalyzed intramolecular amination/cyclopropanation of ynamides with azides. In 2015, Ye et al. successfully realized the related intermolecular transformation and developed a gold‐catalyzed amination/formal [3 + 2] annulation reaction. In 2015 and 2016, Ye et al. reported the gold‐catalyzed amination/X–H insertion of ynamides with azides. In 2017, Ye et al. further utilized the α ‐imino gold carbenes generated from amination of ynamides with azides into the carbene metathesis reaction. In 2020, Ye et al. realized a copper‐catalyzed enantioselective amination/cyclopropanation of azide‐ynamides via α ‐imino copper carbenes. In 2023, Qian et al. reported a copper‐catalyzed intramolecular amination/C(sp 2 )–H functionalization of azide‐ynamides. In 2023, Ye et al. extended the reaction to heteroatom nucleophiles and developed a copper‐catalyzed enantioselective amination/Doyle‐Kirmse reaction.