Cobaloxime-Catalyzed Markovnikov Wacker-Type Oxidation of Styrenes

The traditional Wacker–Tsuji oxidation is fundamentally constrained by reliance on expensive noble metals and corrosive additives. Herein, we report a cobaloxime-catalyzed Wacker-type oxidation of styrenes using ambient air as the sole reoxidant and Et3SiH as a cheap and mild hydride donor. Operating under thermally driven conditions, this robust and cost-effective biomimetic system achieves exclusive Markovnikov selectivity, accommodates a broad scope of functionalized styrenes, and shows excellent performance in the late-stage modification of complex pharmaceuticals and natural products. Its practical utility is further validated through a gram-scale synthesis.