Electrochemical C-H Sulfonylation of N,N-Dialkylanilines: Sequential Dehydrogenative Cross-Coupling and Sulfonylation

An electrochemical method enables direct sulfonylation of N,N-dialkylaniline derivatives through sequential dehydrogenative cross-coupling and C-H-activated sulfonylation. This method utilizes sulfonyl hydrazides, facilitating the one-pot synthesis of N,N,N',N'-tetramethyl-3-arylsulfonyl-[1,1'-biphenyl]-4,4'-diamine derivatives from N,N-dimethylaniline. Furthermore, it efficiently introduces arylsulfonyl groups at the ortho position of various N,N-dialkylanilines. Optimized conditions include a CH₃CN solvent system, a carbon anode, a nickel cathode, and an n-Bu₄NBF₄ electrolyte. The method demonstrates a broad substrate scope, achieving high yields across various arylsulfonyl hydrazides and N,N-dialkylanilines without requiring transition metal catalysts or external oxidants, thereby providing an efficient route to sulfonylated aniline derivatives.