Acid-Mediated Intramolecular\nCyclizations of (<i>N</i>‑Aryl)-acetylenic Sulfonamides:\nSynthesis of Fused\nand Spirocyclic Sultams

Herein, we report acid-mediated divergent annulations\nof (<i>N</i>-aryl)-alkynyl sulfonamides. The substituent\nat the <i>para</i> position of the <i>N</i>-aryl\ngroup determines\ntwo diverse reaction paths, leading to the selective assembly of benzo-fused\nsultams and spirocyclic sultams. This strategy provides a series of\nbenzo/spiro-sultams with wide functional group compatibility and good\nto excellent yields under mild reaction conditions. Additionally,\nscale-up reaction and further transformations of the products were\nalso carried out to demonstrate the utility of the protocol.