Palladium Oxidase Catalysis: Selective Oxidation of Organic Chemicals by Direct Dioxygen-Coupled Turnover

Selective aerobic oxidation of organic molecules is a fundamental and practical challenge in modern chemistry. Effective solutions to this problem must overcome the intrinsic reactivity and selectivity challenges posed by the chemistry of molecular oxygen, and they must find application in diverse classes of oxidation reactions. Palladium oxidase catalysis combines the versatility of PdII‐mediated oxidation of organic substrates with dioxygen‐coupled oxidation of the reduced palladium catalyst to enable a broad range of selective aerobic oxidation reactions. Recent developments revealed that cocatalysts (e.g. CuII, polyoxometalates, and benzoquinone) are not essential for efficient oxidation of Pd0 by molecular oxygen. Oxidatively stable ligands play an important role in these reactions by minimizing catalyst decomposition, promoting the direct reaction between palladium and dioxygen, modulating organic substrate reactivity and permitting asymmetric catalysis. A long‐term goal of synthetic and catalytic chemistry for several decades has been the selective oxidation of organic chemicals with molecular oxygen. This goal is rapidly becoming a reality with the development of new “palladium oxidase” reactions. New catalysts exhibit improved stability and activity and they utilize oxidatively stable ligands that modulate reaction selectivity.