Base-Mediated Convenient Synthesis of 4-Sulfonyl-1,2,3-NH-Triazoles and (Z)-beta-Amidovinyl Sulfones using (E)-beta-Iodovinyl Sulfones

Multifunctional β-iodovinyl sulfones have emerged as versatile synthetic precursors, serving as key building blocks for diverse synthetic transformations. In this study, we report a K2CO3-mediated formal [3+2]-cycloaddition of (E)-β-iodovinyl sulfones with sodium azide under mild, metal-free conditions, affording 1,2,3-NH-triazole-derived sulfones in moderate to good yields. Furthermore, an efficient Cs₂CO₃-promoted N-vinylation of β-iodovinyl sulfones with sulfonamides and acyclic/cyclic amides has been developed, affording (Z)-β-amidovinyl sulfones in good to high yields with excellent stereoselectivity. The scope and generality of these protocols were successfully demonstrated using a wide range of β-iodovinyl sulfones bearing diverse functional groups. Notably, the present protocols are reliable at the gram scale, and potential synthetic applications of sulfonyl-1,2,3-NH-triazoles as well as -amidovinyl sulfones have been successfully explored