Divergent Access to Polycyclic N-Heterocyclic Compounds through Büchner-Type Dearomatization Enabled Cycloisomerization of Diynamides under Gold Catalysis

Catalytic dearomatization has been considered as a valuable approach to convert readily accessible flat molecules to products with three-dimensional frameworks. Herein, an unprecedented gold-catalyzed oxidative Büchner-type cyclopropanation is described that enables the cycloisomerization of diynamides. By variation of the position of substituents on the phenyl ring, a variety of fused N-heterocyclic products with challenging structural skeletons were obtained divergently.