Improved Synthesis of 1,2,3‐Triazolium Salts via Oxidative [3+2] Cycloaddition of Triazenes with Alkynes and Their Deprotonative Functionalization

1,2,3‐Triazolium units are present in various functionalized molecules, including mesoionic carbenes, organocatalysts, and anion recognition receptors. While the oxidative [3+2] cycloaddition of triazenes with alkynes is one of the most efficient methods to construct the 1,2,3‐triazolium skeleton, the effect of reaction parameters and substrate scope in the reaction has not been fully studied. Herein, we developed a practical protocol for the synthesis of 1,2,3‐triazolium salts and significantly expanded the substrate scope of triazenes and alkynes. Also, an efficient method for the deprotonative functionalization of 1,2,3‐triazolium salts was achieved. A structurally diverse 1,2,3‐triazolium salts were successfully synthesized through oxidative [3+2] cycloaddition of triazenes and alkynes. Moreover, a practical method for the deprotonative functionalization of 1,2,3‐triazolium salts under air was also developed.