Transition‐Metal‐Catalyzed Denitrogenative Transannulation: Converting Triazoles into Other Heterocyclic Systems

Transition metal catalyzed denitrogenative transannulation of a triazole ring has recently received considerable attention as a new concept for the construction of diverse nitrogen‐containing heterocyclic cores. This method allows a single‐step synthesis of complex nitrogen heterocycles from easily available and cheap triazole precursors. In this Minireview, recent progress of the transition metal catalyzed denitrogenative transannulation of a triazole ring, which was discovered in 2007, is discussed.