Ruthenium-Catalyzed Cycloaddition of Alkynes and Organic Azides

Cp*RuCl(PPh3)2 is an effective catalyst for the regioselective “fusion” of organic azides and terminal alkynes, producing 1,5-disubstituted 1,2,3-triazoles. Internal alkynes also participate in this catalysis, resulting in fully substituted 1,2,3-triazoles.