Copper-Catalyzed Asymmetric Cyclizative Sulfinamidation: Forging Indole-Based Stereogenic Sulfur(IV) Centers and Atropisomeric Chirality

The structural prominence of indole-based sulfur-containing compounds in pharmacologically relevant substances stems from their versatile biofunctional capabilities. Despite their significance, the stereogenic elements embedded in these structures have frequently been overlooked in drug discovery endeavors primarily due to the absence of efficient synthetic methodologies. Here, we introduce a groundbreaking strategy for the enantioselective synthesis of indole-based sulfinamides via a copper-catalyzed asymmetric nucleophilic cyclization and sulfinamidation reaction. Utilizing ortho-alkynylanilines and sulfinylamines, this method achieves a broad spectrum of sulfinamides with complete atom economy, establishing a new paradigm in synthetic efficiency. Our approach not only facilitates the formation of S-chirogenic sulfinamides but also concurrently constructs products featuring both stereogenic sulfur and atropisomeric chirality. Comprehensive mechanistic investigations, complemented by density functional theory (DFT) calculations, provide deep insights into the reaction mechanism, particularly in elucidating the S-stereogenic and atropisomeric control during the cyclization and sulfinamidation processes.