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Herein, an I2‐catalyzed unprecedented cycloisomerization of ynamides is developed, furnishing various functionalized bis(indole) derivatives in generally good to excellent yields with wide substrate scope and excellent atom‐economy. This protocol not only represents the first molecular‐iodine‐catalyzed tandem complex alkyne cycloisomerizations, but also constitutes the first chemoselective cycloisomerization of tryptamine‐ynamides involving distinctively different C(sp3)−C(sp3) bond cleavage and rearrangement. Moreover, chiral tetrahydropyridine frameworks containing two stereocenters are obtained with moderate to excellent diastereoselectivities and excellent enantioselectivities. Meanwhile, cycloisomerization and aromatization of ynamides produce pyrrolyl indoles with high efficiency enabled by I2. Additionally, control experiments and theoretical calculations reveal that this reaction probably undergoes a tandem 5‐exo‐dig cyclization/rearrangement process. [ABSTRACT FROM AUTHOR]

Ynamides are electron‐rich heteroatom‐substituted alkynes with C−C triple bond directly tethered to the amide group. Over the past decades, ynamides have proven to be versatile reagents for organic synthesis and have received extensive attention. Compared with the well‐established ionic reactions of ynamides, radical‐based ynamide reactions have been exploited relatively seldom. Herein, radical reactions of ynamides, classified by radical attack at the α‐position and β‐position of ynamides, are reviewed by highlighting the reaction selectivity, scope, mechanism, and applicability. The aim of this review is to provide a comprehensive summarization of these advances, casting light on the further development of ynamide chemistry. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: An efficient copper‐catalyzed carbocyclization of silyl enol ether tethered ynamides has been developed, allowing rapid and practical construction of diverse 2‐azabicyclo[3.2.0] compounds in generally good to excellent yields with broad substrate scope under mild reaction conditions. Importantly, this protocol not only constitutes a rare example of non‐noble metal‐catalyzed alkyne carbocyclization, but also represents a rare cyclization on the β‐position of π‐tethered ynamides. The possibility of asymmetric carbocyclization via kinetic resolution also emerges. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: An efficient copper‐catalyzed carbocyclization of silyl enol ether tethered ynamides has been developed, allowing rapid and practical construction of diverse 2‐azabicyclo[3.2.0] compounds in generally good to excellent yields with broad substrate scope under mild reaction conditions. Importantly, this protocol not only constitutes a rare example of non‐noble metal‐catalyzed alkyne carbocyclization, but also represents a rare cyclization on the β‐position of π‐tethered ynamides. The possibility of asymmetric carbocyclization via kinetic resolution also emerges. [ABSTRACT FROM AUTHOR]