Zeo-Click Chemistry: Copper(I)-Zeolite-Catalyzed Cascade Reaction; One-Pot Epoxide Ring-Opening and Cycloaddition

Copper(I)‐modified zeolites, especially CuI–USY, proved to be very efficient catalysts in multi‐component reactions of epoxides with sodium azide and terminal alkynes. Such catalysts allow highly regio‐ and stereoselective syntheses ofhydroxymethylated triazoles. These heterogeneous, modified zeolites can easily be recovered and reused. Moreover, the cascade reaction was best performed in water at room temperature, rendering all the processes truly green. Detailed investigations revealed the role the CuI‐modified zeolites play both during the epoxide ring‐opening and cycloaddition steps. Copper(I)‐modified zeolites, especially CuI–USY, are efficient and reusable heterogeneous catalysts for the one‐pot condensation of epoxides with sodium azide and terminal alkynes in water at room temperature. Hydroxymethylated triazoles are thus regio‐ and stereoselectively obtained in good to high yields.