Iron-catalyzed 1,2-diketone synthesis via benzoin condensation/oxidation in water

In this study, we have developed a methodology for the synthesis of 1,2-diketones via aerobic oxidation of benzaldehyde derivatives in water using N-heterocyclic carbene (NHC) catalysis. This approach involves a two-step one-pot process: benzoin condensation catalyzed by NHC, followed by FeS-catalyzed aerobic oxidation. By employing water as the reaction medium with Triton X as a surfactant, we have established an environmentally benign reaction system that eliminates the need for organic solvents. Through a series of control experiments, we have elucidated the roles of the NHC catalyst and FeS in the reaction mechanism.