Metal‐Free Direct Synthesis of <i>N</i>‐Sulfonyl Amidines from Thioamides and Electron Deficient <i>N</i>‐Sulfonylamides

Abstract A metal‐free, efficient synthesis of N ‐sulfonyl amidines has been demonstrated from easily accessible thioamides and electron‐deficient sulfonyl amides. The amidation reaction is facile at room temperature with low sulfonyl amide loading. The reaction with thioamides is illustrated with various thioamides and electron‐deficient sulfonyl amides with broad substrate scope. The utility of N ‐sulfonyl amidine synthesis is validated with late‐stage drug functionalization.