The reaction of sodium azide with β-monosubstituted-α-chloroenamines (generated from tertiary amides) yields either 5-dialkylamino-1,2,3-triazoles or 2-amino-1-azirines according to the basicity of the amine substituent.
Henriet, M., Houtekie, M., Techy, B., Touillaux, R., & Ghosez, L. (1980). Synthesis of 5-dialkylamino-1,2,3-triazoles and 2-amino-1-azirines From Tertiary Amides. Tetrahedron Letters, 21(2), 223-226. https://doi.org/10.1016/S0040-4039(00)71421-3 (Original work published 1980)