Electricity-Induced Alkylative Truce–Smiles Rearrangement of <i>N</i> -Arylsulfonylpropiolamides: A Cascade to Functionalized Isothiazolidinones

Electrochemistry offers new opportunities for radical Truce-Smiles rearrangement (TSR). Herein, we disclose an electrochemical decarboxylation of redox-active esters that triggers a nondesulfonylative TSR of <i>N</i>-arylsulfonylpropiolamides, delivering 4-aryl-5-alkyl isothiazolidinone dioxides. We uncovered a subtle interplay between anodically generated metallic salts and the selected electrolyte anion, favoring either kinetic or thermodynamic isomers with moderate and high diastereoselectivities, respectively. Further transformation smoothly provides the formal desulfonylative TSR adduct, expanding the synthetic utility of the method.