Rhodium-Catalyzed Azide-Alkyne Cycloaddition of Internal Ynamides: Regioselective Assembly of 5-Amino-Triazoles under Mild Conditions

A rhodium-catalyzed azide alkyne-cycloaddition of internal ynamides is described. The reaction could be performed in a wide range of solvents, including aqueous media, under mild conditions without careful exclusion of air and moisture, giving a variety of 5-amino-triazoles as a single regioisomer. The mechanism of regioselective cycloaddition was rationalized by means of density functional theory calculations.