Cycloaddition of <i>N</i>-sulfonyl and <i>N</i>-sulfamoyl azides with alkynes in aqueous media for the selective synthesis of 1,2,3-triazoles

Abstract

The cycloaddition of <i>N</i>-sulfonyl and <i>N</i>-sulfamoyl azides with terminal alkynes generally produces amide derivatives via ketenimine intermediates. We herein delineate a Cu(I) catalyzed method using a prolinamide ligand that selectively generate <i>N-</i>sulfonyl and sulfamoyltriazoles in aqueous media by inhibiting the cleavage of the N¹-N² bond of 5-cuprated triazole intermediates. The present method is mild and tolerant to air, moisture and a wide range of functional groups thereby providing an easy access to a variety of triazole products.