Synthesis of N²-Substituted 1,2,3-Triazoles

We present a novel synthetic approach for the synthesis of the 1,2,3-triazole core, with a particular focus on the direct and regioselective synthesis of the synthetically more challenging triazoles having additional substituents at the N² nitrogen atom. Through treatment of readily accessible geminal diazides with organic hydrazines under mild thermolysis conditions, a broad spectrum of N²-alkyl- and N²-aryl-1,2,3-triazoles are easily generated. For example, geminal diazides derived from ketoesters, ketoamides, and ketones were converted under the reaction conditions. The product structures were confirmed via NMR as well as single-crystal structure analysis.