Vinyl Sulfonium Salts as the Radical Acceptor for Metal-Free Decarboxylative Alkenylation.

Abstract

Vinyl sulfonium salts typically act as an electrophilic Michael acceptor, thus initiating many tandem cyclization reactions. Herein, we disclosed the novel reactivity of vinyl sulfonium salts as a radical acceptor. Using redox-active ester as an alkyl radical precursor, metal-free decarboxylative alkenylation with vinyl sulfonium salts was realized using eosin Y as a photocatalyst. This process features a broad substrate scope and tolerates with a broad range of primary, secondary, tertiary carboxylic acids.