Nucleophilic Attack of Azide at Electrophilic Azides: Formation of N6 Units in Hexazene and Aminopentazole Derivatives

摘要: With the help of selective 15 N labeling experiments, it has been confirmed that nucleophilic attack azide at iminium-activated organic azides leads to short-lived hexazene intermediates. Such species do not only tend a cleavage reaction with formation N-azido compounds, but also undergo ring closure generate unprecedented amidino-functionalized pentazoles. Thus, treatment parent Vilsmeier reagent two equivalents sodium creates an aminopentazole derivative as main product, which is easily characterized by NMR spectroscopy.