Design of Stable Chiral Aminosulfonium Ylides and Their Catalytic Asymmetric Synthesis

• Published in: Angewandte Chemie International Edition 2024-12, Vol.63 (50), p.e202412508-n/a
• Main Authors: Bao, Wen, Wang, Xu‐Jie, Wang, Shao‐Hua, Chen, Shi‐Wu, Liu, Huan‐Huan, Xiang, Shao‐Hua, Tan, Bin
• Format: Article
• Language: English
• Subjects: 2-diazo-1,3-diketone; Asymmetric synthesis; Asymmetry; Chemical synthesis; chiral aminosulfonium ylide; copper-catalysis; Diketones; Enantiomers; Intermediates; intermolecular carbene transfer; Lability; stable S-chirality; Sulfur
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202412508

The isolation and catalytic enantioselective synthesis of configurationally stable S‐stereogenic sulfonium ylides have been significant challenges in the field of asymmetric synthesis. These reactive intermediates are crucial for a variety of synthetic transformations, yet their inherent tendency towards rapid inversion at the sulfur stereocenter has hindered their practical utilization. Conventional approaches have focused on strategies that incorporate a C=S bond‐containing cyclic framework to help mitigate this stereochemical lability. In this work, we present an alternative tactic that leverages the stabilizing influence of an adjacent N‐atom and cyclic sulfide moiety. Exploiting a copper catalyzed enantioselective intermolecular carbene transfer reaction, structurally diverse S‐stereogenic aminosulfonium ylides have been achieved in excellent yields and enantioselectivities. Experimental results indicate that the careful selection of 2‐diazo‐1,3‐diketone precursors is crucial for achieving optimal stereoinduction in this transformation. The resulting highly enantioenriched aminosulfonium ylides allow for further stereospecific elaborations to furnish aminosulfonium ylide oxides and sulfinamide. This work expands the boundaries of chiral sulfonium ylide chemistry, providing access to a broad range of previously elusive S‐stereogenic aminosulfonium ylide scaffolds. Leveraging the stabilization effect of an adjacent N‐atom and a cyclic sulfide moiety, conformationally stable acyclic S‐stereogenic aminosulfonium ylides were accessed for the first time with excellent efficiency and enantiocontrol via a copper catalyzed enantioselective intermolecular carbene transfer reaction. The resulting products allow for further stereospecific elaborations to afford aminosulfonium ylide oxides and sulfinamide.