Synthesis of vinyl azides
Low loadings of a gold catalyst derived from a functionalized biaryl-2-ylphosphine ligand (WangPhos) enable a direct addition of in situ generated hydrazoic acid to terminal as well as internal alkynes.
X. Li, S. Liao, Z. Wang, L. Zhang, Org. Lett., 2017, 19, 3687-3690.
A AgN3-catalyzed hydroazidation of terminal alkynes provides vinyl azides in good yields. AgN3 proved to be a highly robust catalyst, as the loading of AgN3 could be as low as 5 mol %.
S. Cao, Q. Ji, H. Li, M. Pang, H. Yuan, J. Zhang, X. Bi, J. Am. Chem. Soc., 2020, 142, 7083-7091.
A general silver-catalyzed hydroazidation of unactivated terminal alkynes with trimethylsilyl azide in the presence of water afforded the corresponding vinyl azides in good to excellent yields. This reaction has a broad substrate scope, good functional group tolerance, simple operation, and high reaction efficiency, thus providing an easy access to various functionalized vinyl azides.
Z. Liu, P. Liao, X. Bi, Org. Lett., 2014, 16, 3668-3671.
The nucleophilic addition of sodium azide to 1,2-allenyl esters regio- and stereoselectively generates vinyl azides in excellent yields. A sequential reaction for the synthesis of pyrroles using 1-allyllic 1,2-allenyl esters as substrates is developed on the basis of a domino process involving nucleophilic addition, cycloaddition, denitrogenation, and aromatization.
X. Huang, R. Shen, T. Zhang, J. Org. Chem., 2007, 72, 1534-1537.