Mechanochemical Nickel-Catalyzed Dechlorination-Deuteration of Aryl Chlorides via Piezoelectric-Promoted Ar–Zn–X Intermediates

Direct dechlorination-deuteration of aryl chlorides continues to pose a significant challenge in traditional solution-phase chemistry due to the high bond dissociation energy of the C–Cl bond. Herein, we report a mechanochemically driven nickel-catalyzed dechlorination-deuteration of aryl chlorides under minimal-solvent conditions. Mechanistic studies, including Hammett analysis, kinetic isotope effect (KIE) measurements, and intermediate quenching experiments, support a catalytic cycle involving a reversible oxidative addition to generate aryl-nickel intermediates, which then undergo transmetalation to form aryl-zinc species, subsequently undergoing electrophilic deuteration with D₂O. The piezoelectric material BaTiO₃ plays a key role by accelerating turnover within the nickel catalytic cycle and enhancing the formation of reactive arylzinc intermediates. The protocol is broadly applicable to chlorinated arenes and drug-like molecules, providing deuterated compounds with high efficiency and isotopic purity.