Au-Pd@ZnO alloy nanoparticles: a promising heterogeneous photocatalyst toward decarboxylative trifluoromethylation under visible-light irradiation

Considering the high synergistic effect of Pd and Au supported on semiconductors, herein, we synthesized and characterized Au-Pd@ZnO with high potential toward the decarboxylative trifluoromethylation of aromatic carboxylic acids. Moreover, the combination of pyridine N-oxide and trifluoroacetic anhydride as a cost-effective and easy-to-handle source of CF3 could successfully generate the trifluoromethyl radical in the presence of the photocatalyst. To shed light on the synergistic effect of Pd and Au various control experiments were conducted, indicating the crucial role of both of them. This protocol was applicable to different aromatic and heteroaromatic compounds to deliver desired adducts in moderate to good yields and high functional group tolerance. Au-Pd@ZnO not only exhibited high catalytic performance but can also be recovered three times.