Silver()-catalyzed stereoselective Meyer-Schuster-type rearrangement: synthesis of densely substituted α-iodo α,β-unsaturated thioesters

• Published in: New journal of chemistry 2024-01, Vol.48 (3), p.1164-1171
• Main Authors: Lopes, José L, Baldassari, Lucas L, Lüdtke, Diogo S
• Format: Article
• Language: English
• Subjects: Alkenes; Catalysts; Chemical synthesis; Iodine; Silver; Stereoselectivity; Thioesters
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d3nj05144g

Herein, we report our approach for a Meyer-Schuster type rearrangement to access α-iodo α,β-unsaturated thioesters from propargyl thioalkynes using a silver( i ) catalyst and N -iodosuccinimide as an electrophilic iodine source. The reaction proceeds smoothly for a range of propargyl thioalkynes, thus delivering tri- and tetrasubstituted olefins in good yields and, for a number of examples, ( Z )-selectivity. The silver catalyst presumably plays a dual role involving both the activation of the π-system by the alkynophilic Ag( i ) and the activation of the NIS, ultimately leading to a sulfur-stabilized vinyl cation/ketenethionium intermediate. This reactive intermediate is trapped intramolecularly to yield an oxetane, which then readily undergoes decomposition to deliver the final product. Herein, we report our approach for a Meyer-Schuster type rearrangement to access α-iodo α,β-unsaturated thioesters from propargyl thioalkynes using a silver( i ) catalyst and N -iodosuccinimide as an electrophilic iodine source.