Ring expansion of α-azidoazines: formation of the first examples of fully unsaturated monocyclic 1,3,5-triazepines
Abstract
Photolysis of the 2-azidopyridines (3), 2-azidopyrazines (6), and 4-azidopyrimidines (8), having a strong electron-donating substituent, in the presence of methoxide ion or diethylamine results in ring expansion to give the corresponding fully unsaturated 1,3-diazepines (5) and 1,3,5-triazepines (7) and (9).