Electrochemical Three-Component Synthesis of Vinyl Sulfonamides via Decarboxylative Sulfonylation of Cinnamic Acids

An efficient, electrochemical three-component reaction for the synthesis of vinyl sulfonamides from cinnamic acids, SO₂, and amines is reported. This metal-free protocol utilizes inexpensive graphite electrodes and easy-to-use SO₂ stock solutions to facilitate a decarboxylative transformation under mild conditions. The reaction proceeds with high regio- and stereoselectivity, affording (E)-β-styryl sulfonamides without double-bond translocation. The use of cinnamic acid derivatives as biobased feedstocks, combined with the demonstrated scalability and anolyte reusability, highlights the potential of this approach for a sustainable synthesis of the important vinyl sulfonamide scaffold.