Rotating magnetic field-enhanced PPh3-mediated deoxygenative C–N coupling of nitroarenes with boronic acids

Abstract

Diarylamines are privileged motifs in pharmaceuticals, agrochemicals, and functional materials, yet their synthesis typically relies on transition-metal-catalyzed C–N couplings that require prefunctionalized anilines. We report a solvent-free electromagnetic mechanochemical protocol that enables PPh₃-promoted deoxygenative C–N coupling of nitroarenes with boronic acids under a rotating magnetic field. The synergistic action of electromagnetic induction and mechanical collision activates simple triphenylphosphine to promote C–N bond formation without silanes, light, electrochemistry, or designer phosphines. Notably, bromo- and iodo-substituted substrates—often incompatible with conventional metal-catalyzed systems—remained completely intact, highlighting the exceptional halogen tolerance of this protocol. The reaction proceeds smoothly in air and without solvent, demonstrating a robust, sustainable, and magnetically driven strategy for C–N bond construction from simple and abundant feedstocks.