Electrochemical oxidation induced intermolecular aromatic C-H imidation.

Area of Science:

• Organic Chemistry
• Electrochemistry
• Synthetic Methodology

Background:

• Dehydrogenative aryl C-H/N-H cross-coupling is key for introducing nitrogen into aromatic structures.
• Existing methods often require external oxidants or catalysts, limiting efficiency and scope.

Purpose of the Study:

• To develop a novel, catalyst-free, and oxidant-free electrochemical method for aryl C-H/N-H cross-coupling.
• To achieve high regioselectivity in the formation of nitrogen-functionalized aromatics.

Main Methods:

• Electrochemical oxidation to induce intermolecular cross-coupling between arenes and sulfonimides.
• Utilizing a proton-coupled electron transfer (PCET) mechanism mediated by tetrabutylammonium acetate and anode oxidation.
• Cyclic voltammetry for mechanistic investigation.

Main Results:

• Successful intermolecular cross-coupling of diverse arenes and heteroarenes with various sulfonimides.
• High regioselectivity achieved via an N-radical addition pathway.
• Demonstrated applicability to alkenes and subsequent deprotection to yield aryl sulfonamides or anilines.

Conclusions:

• The developed electrochemical method provides an efficient and sustainable approach for synthesizing nitrogen-containing aromatic compounds.
• The catalyst-free and oxidant-free conditions offer significant advantages over traditional cross-coupling reactions.
• This methodology expands the synthetic toolbox for accessing valuable aryl sulfonamides and aniline derivatives.