Multicomponent hydrosulfonylation of alkynes for the synthesis of vinyl sulfones

Abstract

Vinyl sulfones are important structural motifs with a wide range of applications in the biomedical field. Although the hydrosulfonylations of alkynes have provided straightforward strategies for the synthesis of vinyl sulfones, these methods still exhibit several drawbacks, such as the use of large amounts of transition metal catalysts or/and additional additives. Herein, we report an efficient and mild multicomponent reaction (MCR) for the preparation of vinyl sulfones achieved by carrying out hydrosulfonylation of alkynes with the corresponding aryl diazonium salts, K₂S₂O₅ and thiophenols at room temperature without any metal catalysts or additives. This transformation was the first example of a thiophenol as a hydrogen source reacting with vinyl radical with the advantages of high chemoselectivity and step-economy. Notably, the method was found to also be applicable to aliphatic alkynes, circumventing the limitations of existing methods, and a gram-scale experiment proceeded smoothly, proving the practicality of the methodology.