Intrinsic Spin Effect beyond Aqueous Systems: Selectivity Control in Organic Electrochemistry via Spin-Polarized Radical Intermediates

Spin manipulation has emerged as a transformative strategy in boosting electrochemical reactions. Yet, its application in organic electrosynthesis involving diffusive radical intermediates remains less explored compared to aqueous systems. Herein, we report a systematic study of spin-controlled organic electrosynthesis via precise regulation of radical coupling and hydrogenation pathways in solution during the electroreduction of benzyl chloride. By leveraging ferromagnetic electrodes with external magnetic fields, spin-polarized electron transfer fundamentally alters the spin states of radical intermediate, selectively suppressing radical coupling by 70% while achieving 85% selectivity for hydrogenated product─performance unattainable through conventional potential control. Notably, the contribution of the MHD effect was further excluded with the absence of a magnetic field effect using nonmagnetic electrodes, highlighting the spin manipulation as the intrinsic mechanism underlying the observed magnetic field effects. Our findings establish spin polarization as an orthogonal methodology for reaction pathway engineering and selectivity enhancement in sustainable organic chemistry.