Electrochemical C-H Sulfonylation of Hydrazones.

We have developed an electrochemical method for the direct C-H sulfonylation of aldehyde hydrazones using sodium sufinates as the sulfonylating agent under supporting electrolyte-free conditions. This straightforward sulfonylation strategy afforded a library of ( E )-sufonylated hydrazones with high tolerance of various functional groups. The radical pathway of this reaction has been revealed by the mechanistic studies.