Asymmetric catalytic reductive transformation of S(VI) to S(IV) for modular access to S(IV)-stereogenic sulfilimine derivatives.

Sulfur plays a pivotal role across diverse fields owing to its distinctive chemical and biological properties, thereby propelling the development of stereoselective synthesis of enantioenriched S(IV)-stereogenic scaffolds. While oxidative strategies for generating S-chiral frameworks have witnessed emerging development, the catalytic reduction of S(VI) species to furnish enantioenriched S(IV) scaffolds remains largely overlooked. Herein, we present an enantioselective catalytic method to access S(IV)-stereogenic sulfinimidate ester scaffolds through a distinct catalytic asymmetric formal reductive transformation of S(VI)-sulfonimidoyl chlorides. Using a naturally occurring, cost-effective quinine organocatalyst, we achieved high enantioselectivity in chiral sulfinimidate ester formation via asymmetric S─O bond formation. The catalyst plays dual critical roles, facilitating both the reduction of S(VI) substrates and the catalytic stereoselective formation of S─O bonds. This approach offers a rapid and efficient pathway to sulfinimidate esters, which serves as versatile intermediates for subsequent modular access to diverse S-chiral sulfilimine and sulfinamidine scaffolds, with promising applications in agrochemical and pharmaceutical discovery.